diff options
Diffstat (limited to 'doc/documentation')
81 files changed, 21714 insertions, 0 deletions
diff --git a/doc/documentation/Makefile.am b/doc/documentation/Makefile.am new file mode 100644 index 000000000..7b844b985 --- /dev/null +++ b/doc/documentation/Makefile.am | |||
@@ -0,0 +1,233 @@ | |||
1 | # This Makefile.am is in the public domain | ||
2 | docdir = $(datadir)/doc/gnunet/ | ||
3 | |||
4 | infoimagedir = $(infodir)/images | ||
5 | |||
6 | #DOT_FILES = images/$(wildcard *.dot) | ||
7 | |||
8 | #DOT_VECTOR_GRAPHICS = \ | ||
9 | # $(DOT_FILES:%.dot=%.eps) \ | ||
10 | # $(DOT_FILES:%.dot=%.pdf) | ||
11 | |||
12 | AM_MAKEINFOHTMLFLAGS = --no-split --css-ref=docstyle.css | ||
13 | |||
14 | dist_infoimage_DATA = \ | ||
15 | images/gnunet-gtk-0-10-gns-a-done.png \ | ||
16 | images/gnunet-gtk-0-10-gns-a.png \ | ||
17 | images/daemon_lego_block.png \ | ||
18 | images/gnunet-gtk-0-10-gns.png \ | ||
19 | images/gnunet-0-10-peerinfo.png \ | ||
20 | images/gnunet-gtk-0-10-identity.png \ | ||
21 | images/gnunet-fs-gtk-0-10-star-tab.png \ | ||
22 | images/gnunet-gtk-0-10.png \ | ||
23 | images/gnunet-gtk-0-10-download-area.png \ | ||
24 | images/gnunet-gtk-0-10-search-selected.png \ | ||
25 | images/gnunet-gtk-0-10-fs-menu.png \ | ||
26 | images/gnunet-gtk-0-10-traffic.png \ | ||
27 | images/gnunet-gtk-0-10-fs.png \ | ||
28 | images/gnunet-namestore-gtk-phone.png \ | ||
29 | images/gnunet-gtk-0-10-fs-publish-editing.png \ | ||
30 | images/gnunet-namestore-gtk-vpn.png \ | ||
31 | images/gnunet-gtk-0-10-fs-published.png \ | ||
32 | images/gnunet-setup-exit.png \ | ||
33 | images/gnunet-gtk-0-10-fs-publish.png \ | ||
34 | images/iceweasel-preferences.png \ | ||
35 | images/gnunet-gtk-0-10-fs-publish-select.png \ | ||
36 | images/iceweasel-proxy.png \ | ||
37 | images/gnunet-gtk-0-10-fs-publish-with-file_0.png \ | ||
38 | images/service_lego_block.png \ | ||
39 | images/gnunet-gtk-0-10-fs-publish-with-file.png \ | ||
40 | images/service_stack.png \ | ||
41 | images/gnunet-gtk-0-10-fs-search.png \ | ||
42 | images/gnunet-tutorial-service.png \ | ||
43 | images/gnunet-tutorial-system.png \ | ||
44 | images/daemon_lego_block.svg \ | ||
45 | images/lego_stack.svg \ | ||
46 | images/service_lego_block.svg \ | ||
47 | images/structure.dot | ||
48 | |||
49 | # images/$(wildcard *.png) \ | ||
50 | # images/$(wildcard *.svg) | ||
51 | # $(DOT_FILES:%.dot=%.png) | ||
52 | |||
53 | #DOT_OPTIONS = \ | ||
54 | # -Gratio=.9 -Gnodesep=.005 -Granksep=.00005 \ | ||
55 | # -Nfontsite=9 -Nheight=.1 -Nwidth=.1 | ||
56 | |||
57 | # .dot.png: | ||
58 | # $(AM_V_DOT)$(DOT) -Tpng $(DOT_OPTIONS) < "$<" > "$(srcdir)/$@.tmp"; \ | ||
59 | # mv "$(srcdir)/$@.tmp" "$(srcdir)/$@" | ||
60 | |||
61 | # .dot.pdf: | ||
62 | # $(AM_V_DOT)$(DOT) -Tpdf $(DOT_OPTIONS) < "$<" > "$(srcdir)/$@.tmp"; \ | ||
63 | # mv "$(srcdir)/$@.tmp" "$(srcdir)/$@" | ||
64 | |||
65 | # .dot.eps: | ||
66 | # $(AM_V_DOT)$(DOT) -Teps $(DOT_OPTIONS) < "$<" > "$(srcdir)/$@.tmp"; \ | ||
67 | # mv "$(srcdir)/$@.tmp" "$(srcdir)/$@" | ||
68 | |||
69 | # .png.eps: | ||
70 | # $(AM_V_GEN)convert "$<" "$@-tmp.eps"; \ | ||
71 | # mv "$@-tmp.eps" "$@" | ||
72 | |||
73 | # pdf-local: $(DOT_FILES=%.dot=$(top_srcdir)/%.pdf) | ||
74 | # info-local: $(DOT_FILES=%.dot=$(top_srcdir)/%.png) | ||
75 | # ps-local: $(DOT_FILES=%.dot=$(top_srcdir)/%.eps) \ | ||
76 | # $(top_srcdir)/%D%/images/coreutils-size-map.eps | ||
77 | # dvi-local: ps-local | ||
78 | |||
79 | gnunet_tutorial_examples = \ | ||
80 | 001.c \ | ||
81 | 002.c \ | ||
82 | 003.c \ | ||
83 | 004.c \ | ||
84 | 005.c \ | ||
85 | 006.c \ | ||
86 | 007.c \ | ||
87 | 008.c \ | ||
88 | 009.c \ | ||
89 | 010.c \ | ||
90 | 011.c \ | ||
91 | 012.c \ | ||
92 | 013.c \ | ||
93 | 013.1.c \ | ||
94 | 014.c \ | ||
95 | 015.c \ | ||
96 | 016.c \ | ||
97 | 017.c \ | ||
98 | 018.c \ | ||
99 | 019.c \ | ||
100 | 020.c \ | ||
101 | 021.c \ | ||
102 | 022.c \ | ||
103 | 023.c \ | ||
104 | 024.c \ | ||
105 | 025.c \ | ||
106 | 026.c | ||
107 | |||
108 | info_TEXINFOS = \ | ||
109 | gnunet.texi \ | ||
110 | gnunet-c-tutorial.texi | ||
111 | |||
112 | gnunet_TEXINFOS = \ | ||
113 | chapters/developer.texi \ | ||
114 | chapters/installation.texi \ | ||
115 | chapters/philosophy.texi \ | ||
116 | chapters/user.texi \ | ||
117 | chapters/vocabulary.texi \ | ||
118 | chapters/configuration.texi \ | ||
119 | chapters/contributing.texi \ | ||
120 | fdl-1.3.texi \ | ||
121 | gpl-3.0.texi | ||
122 | |||
123 | EXTRA_DIST = \ | ||
124 | $(gnunet_TEXINFOS) \ | ||
125 | $(gnunet_tutorial_examples) \ | ||
126 | htmlxref.cnf \ | ||
127 | run-gendocs.sh \ | ||
128 | docstyle.css | ||
129 | |||
130 | |||
131 | # $(DOT_FILES) \ | ||
132 | # $(DOT_VECTOR_GRAPHICS) | ||
133 | |||
134 | DISTCLEANFILES = \ | ||
135 | gnunet.cps \ | ||
136 | gnunet-c-tutorial.cps \ | ||
137 | chapters/developer.cps \ | ||
138 | chapters/installation.cps \ | ||
139 | chapter/philosophy.cps \ | ||
140 | chapters/user.cps \ | ||
141 | chapters/configuration.cps \ | ||
142 | chapters/vocabulary.cps \ | ||
143 | fdl-1.3.cps \ | ||
144 | gpl-3.0.cps | ||
145 | |||
146 | # if HAVE_EXTENDED_DOCUMENTATION_BUILDING | ||
147 | daemon_lego_block.png: images/daemon_lego_block.svg | ||
148 | convert images/daemon_lego_block.svg images/daemon_lego_block.png && | ||
149 | pngcrush images/daemon_lego_block.png images/daemon_lego_block.png | ||
150 | |||
151 | service_lego_block.png: images/service_lego_block.svg | ||
152 | convert images/service_lego_block.svg images/service_lego_block.png && | ||
153 | pngcrush images/service_lego_block.png images/serivce_lego_block.png | ||
154 | |||
155 | lego_stack.png: images/lego_stack.svg | ||
156 | convert images/lego_stack.svg images/lego_stack.png && | ||
157 | pngcrush images/lego_stack.png images/lego_stack.png | ||
158 | |||
159 | # FIXME: The usage of 'date' strings causes a warning. | ||
160 | # version.texi: | ||
161 | # echo "@set UPDATED $(date +'%d %B %Y')" > $@ | ||
162 | # echo "@set UPDATED-MONTH $(date +'%B %Y')" >> $@ | ||
163 | # echo "@set EDITION $(PACKAGE_VERSION)" >> $@ | ||
164 | # echo "@set VERSION $(PACKAGE_VERSION)" >> $@ | ||
165 | |||
166 | # Workaround for makeinfo error. Whcih in turn introduces more | ||
167 | # date-related 'warnings'. Well. | ||
168 | version2.texi: | ||
169 | echo "@set UPDATED $(date +'%d %B %Y')" > $@ | ||
170 | echo "@set UPDATED-MONTH $(date +'%B %Y')" >> $@ | ||
171 | echo "@set EDITION $(PACKAGE_VERSION)" >> $@ | ||
172 | echo "@set VERSION $(PACKAGE_VERSION)" >> $@ | ||
173 | |||
174 | # FIXME: rm *.html and *.pdf | ||
175 | #doc-clean: | ||
176 | # @rm *.aux *.log *.toc *.cp *.cps | ||
177 | |||
178 | doc-all-install: | ||
179 | @mkdir -p $(DESTDIR)/$(docdir) | ||
180 | @mkdir -p $(DESTDIR)/$(infoimagedir) | ||
181 | @mkdir -p $(DESTDIR)/$(infodir) | ||
182 | @install -m 0755 gnunet.pdf $(DESTDIR)/$(docdir) | ||
183 | @install -m 0755 gnunet-c-tutorial.pdf $(DESTDIR)/$(docdir) | ||
184 | @install -m 0755 gnunet-c-tutorial.info $(DESTDIR)/$(infodir) | ||
185 | @install -m 0755 gnunet.info $(DESTDIR)/$(infodir) | ||
186 | @install gnunet.html $(DESTDIR)/$(docdir) | ||
187 | @install gnunet-c-tutorial.html $(DESTDIR)/$(docdir) | ||
188 | |||
189 | doc-gendoc-install: | ||
190 | @mkdir -p $(DESTDIR)/$(docdir) | ||
191 | @cp -r manual $(DESTDIR)/$(docdir) | ||
192 | |||
193 | # @cp -r images $(DESTDIR)/$(infoimagedir) | ||
194 | |||
195 | dev-build: version.texi version2.texi | ||
196 | @makeinfo --pdf gnunet.texi | ||
197 | @makeinfo --pdf gnunet-c-tutorial.texi | ||
198 | @makeinfo --html gnunet.texi | ||
199 | @makeinfo --html gnunet-c-tutorial.texi | ||
200 | @makeinfo --no-split gnunet.texi | ||
201 | @makeinfo --no-split gnunet-c-tutorial.texi | ||
202 | |||
203 | # TODO: Add more to clean. | ||
204 | clean: | ||
205 | @rm -f gnunet.pdf | ||
206 | @rm -f gnunet.html | ||
207 | @rm -f gnunet.info | ||
208 | @rm -f gnunet.info-1 | ||
209 | @rm -f gnunet.info-2 | ||
210 | @rm -f gnunet.info-3 | ||
211 | @rm -f gnunet-c-tutorial.pdf | ||
212 | @rm -f gnunet-c-tutorial.info | ||
213 | @rm -f gnunet-c-tutorial.html | ||
214 | @rm -fr gnunet.t2p | ||
215 | @rm -fr gnunet-c-tutorial.t2p | ||
216 | @rm -fr manual | ||
217 | |||
218 | # CLEANFILES = \ | ||
219 | # gnunet.log \ | ||
220 | # gnunet-c-tutorial.log \ | ||
221 | # $(wildcard *.aux) \ | ||
222 | # $(wildcard *.toc) \ | ||
223 | # $(wildcard *.cp) \ | ||
224 | # $(wildcard *.cps) | ||
225 | |||
226 | #.PHONY: version.texi | ||
227 | # if HAVE_EXTENDED_DOCUMENTATION_BUILDING_PDF | ||
228 | |||
229 | # if HAVE_EXTENDED_DOCUMENTATION_BUILDING_HTML | ||
230 | |||
231 | # endif | ||
232 | # endif | ||
233 | # endif | ||
diff --git a/doc/documentation/README.txt b/doc/documentation/README.txt new file mode 100644 index 000000000..e3eb6c8ac --- /dev/null +++ b/doc/documentation/README.txt | |||
@@ -0,0 +1,104 @@ | |||
1 | To be moved to an appropriate section of "how to write documentation" or | ||
2 | "how to contribute to the documentation": | ||
3 | |||
4 | 1. When writing documentation, please use gender-neutral wording when | ||
5 | referring to people, such as singular “they”, “their”, “them”, and | ||
6 | so forth. -> https://en.wikipedia.org/wiki/Singular_they | ||
7 | |||
8 | 2. Keep line length below 74 characters. | ||
9 | - Expection by texi2pdf output so far: URLs will break | ||
10 | (inserted whitespace) when they contain linebreaks | ||
11 | within the @url{} / @uref{}. | ||
12 | |||
13 | 3. Do not use tab characters (see chapter 2.1 texinfo manual) | ||
14 | |||
15 | 4. Use neutral language and third person perspective in the text | ||
16 | |||
17 | 4.1 So, when you refer to a user in general or addressing the user, | ||
18 | refer to (1). | ||
19 | 4.1.1 Unsolved exceptions for canonical reasons: | ||
20 | When refering to Alice, use "she". | ||
21 | When refering to Bob, use "he". | ||
22 | These are long established examples and they | ||
23 | should either be replaced (avoid Alice and Bob | ||
24 | examples when you can) or followed. | ||
25 | |||
26 | 5. Use 2 spaces between sentences, so instead of: | ||
27 | |||
28 | We do this and the other thing. This is done by foo. | ||
29 | |||
30 | Write: | ||
31 | |||
32 | We do this and the other thing. This is done by foo. | ||
33 | |||
34 | 6. Use @footnote{} instead of putting an @*ref{} to the footnote on a | ||
35 | collected footnote-page. | ||
36 | In a 200+ pages handbook it's better to have footnotes accessible | ||
37 | without having to skip over to the end. | ||
38 | |||
39 | 6.1 Avoid unnecessary footnotes, keep the text self-explanatory and | ||
40 | in a simple language where possible/necessary. | ||
41 | |||
42 | * Completion Levels: | ||
43 | |||
44 | ** chapters/philosophy: around 100% fixed after initial export. | ||
45 | |||
46 | * What's left to do | ||
47 | |||
48 | - Which Texlive modules are needed? Decrease the size. | ||
49 | - distro specific, or can we set requirements? | ||
50 | - Update the content of gnunet documentation. | ||
51 | - XXX: images are only generated for the html documentation | ||
52 | with gendoc.sh … FIXME! | ||
53 | - XXX: png,dot, and svg images MUST be converted to eps by the | ||
54 | build system. Right now they aren't, as a result: No images. | ||
55 | |||
56 | * How to use (hack) on this | ||
57 | |||
58 | ** with guix | ||
59 | |||
60 | Adjust accordingly, ie read the Guix Documentation: | ||
61 | setenv GUIX_PACKAGE_PATH "gnunet/contrib/packages/guix/packages" | ||
62 | guix environment gnunet-doc | ||
63 | and | ||
64 | guix build -f contrib/packages/guix/gnunet-doc.scm | ||
65 | |||
66 | ** without guix | ||
67 | |||
68 | You need to have Texinfo and Texlive in your path. | ||
69 | sh bootstrap | ||
70 | ./configure --enable-documentation | ||
71 | cd doc | ||
72 | make (format you want) | ||
73 | |||
74 | for example: make html, make info, make pdf | ||
75 | |||
76 | * structure (relations) | ||
77 | |||
78 | ** gnunet.texi | ||
79 | -> chapters/developer.texi | ||
80 | -> chapters/installation.texi | ||
81 | -> chapters/philosophy.texi | ||
82 | -> chapters/user.texi | ||
83 | -> chapters/vocabulary.texi | ||
84 | -> images/* | ||
85 | -> gpl-3.0.texi | ||
86 | -> fdl-1.3.texi | ||
87 | |||
88 | ** gnunet-c-tutorial.texi | ||
89 | -> figs/Service.pdf | ||
90 | -> figs/System.pdf | ||
91 | -> tutorial-examples/*.c | ||
92 | -> gpl-3.0.texi | ||
93 | -> fdl-1.3.texi | ||
94 | |||
95 | - gnunet-c-tutorial-v1.pdf: original LaTeX "gnunet-c-tutorial.pdf". | ||
96 | - man folder: the man pages. | ||
97 | - doxygen folder | ||
98 | - outdated-and-old-installation-instructions.txt: self described within the file. | ||
99 | |||
100 | |||
101 | Use `gendocs', add to the manual/ directory of the web site. | ||
102 | |||
103 | $ cd doc | ||
104 | $ gendocs.sh gnunet "GNUnet 0.10.X Reference Manual" | ||
diff --git a/doc/documentation/chapters/configuration.texi b/doc/documentation/chapters/configuration.texi new file mode 100644 index 000000000..286c72e7a --- /dev/null +++ b/doc/documentation/chapters/configuration.texi | |||
@@ -0,0 +1,5 @@ | |||
1 | @node Configuration Handbook | ||
2 | @chapter Configuration Handbook | ||
3 | |||
4 | This chapter has yet to be written. It is intended to be about in-depth | ||
5 | configuration of GNUnet. | ||
diff --git a/doc/documentation/chapters/contributing.texi b/doc/documentation/chapters/contributing.texi new file mode 100644 index 000000000..5844fb497 --- /dev/null +++ b/doc/documentation/chapters/contributing.texi | |||
@@ -0,0 +1,102 @@ | |||
1 | @node GNUnet Contributors Handbook | ||
2 | @chapter GNUnet Contributors Handbook | ||
3 | |||
4 | @menu | ||
5 | * Contributing to GNUnet:: | ||
6 | * Licenses of contributions:: | ||
7 | * Copyright Assignment:: | ||
8 | * Contributing to the Reference Manual:: | ||
9 | @end menu | ||
10 | |||
11 | @node Contributing to GNUnet | ||
12 | @section Contributing to GNUnet | ||
13 | |||
14 | @node Licenses of contributions | ||
15 | @section Licenses of contributions | ||
16 | |||
17 | GNUnet is a @uref{https://www.gnu.org/, GNU} package. | ||
18 | All code contributions must thus be put under the | ||
19 | @uref{https://www.gnu.org/copyleft/gpl.html, GNU Public License (GPL)}. | ||
20 | All documentation should be put under FSF approved licenses | ||
21 | (see @uref{https://www.gnu.org/copyleft/fdl.html, fdl}). | ||
22 | |||
23 | By submitting documentation, translations, and other content to GNUnet | ||
24 | you automatically grant the right to publish code under the | ||
25 | GNU Public License and documentation under either or both the | ||
26 | GNU Public License or the GNU Free Documentation License. | ||
27 | When contributing to the GNUnet project, GNU standards and the | ||
28 | @uref{https://www.gnu.org/philosophy/philosophy.html, GNU philosophy} | ||
29 | should be adhered to. | ||
30 | |||
31 | @cindex copyright assignment | ||
32 | @node Copyright Assignment | ||
33 | @section Copyright Assignment | ||
34 | We require a formal copyright assignment for GNUnet contributors | ||
35 | to GNUnet e.V.; nevertheless, we do allow pseudonymous contributions. | ||
36 | By signing the copyright agreement and submitting your code (or | ||
37 | documentation) to us, you agree to share the rights to your code | ||
38 | with GNUnet e.V.; GNUnet e.V. receives non-exclusive ownership | ||
39 | rights, and in particular is allowed to dual-license the code. You | ||
40 | retain non-exclusive rights to your contributions, so you can also | ||
41 | share your contributions freely with other projects. | ||
42 | |||
43 | GNUnet e.V. will publish all accepted contributions under the GPLv3 | ||
44 | or any later version. The association may decide to publish | ||
45 | contributions under additional licenses (dual-licensing). | ||
46 | |||
47 | We do not intentionally remove your name from your contributions; | ||
48 | however, due to extensive editing it is not always trivial to | ||
49 | attribute contributors properly. If you find that you significantly | ||
50 | contributed to a file (or the project as a whole) and are not listed | ||
51 | in the respective authors file or section, please do let us know. | ||
52 | |||
53 | @node Contributing to the Reference Manual | ||
54 | @section Contributing to the Reference Manual | ||
55 | |||
56 | @itemize @bullet | ||
57 | |||
58 | @item When writing documentation, please use | ||
59 | @uref{https://en.wikipedia.org/wiki/Singular_they, gender-neutral wording} | ||
60 | when referring to people, such as singular “they”, “their”, “them”, and so | ||
61 | forth. | ||
62 | |||
63 | @item Keep line length below 74 characters, except for URLs. | ||
64 | URLs break in the PDF output when they contain linebreaks. | ||
65 | |||
66 | @item Do not use tab characters (see chapter 2.1 texinfo manual) | ||
67 | |||
68 | @item Use neutral language and third person perspective in the text | ||
69 | |||
70 | @item So, when you refer to a user in general or addressing the user, | ||
71 | refer to (1). | ||
72 | @itemize @bullet | ||
73 | @item Unsolved exceptions for canonical reasons: When refering to Alice, | ||
74 | use "she". When refering to Bob, use "he". These are long established | ||
75 | examples and they should either be replaced (avoid Alice and Bob | ||
76 | examples when you can) or followed. | ||
77 | @end itemize | ||
78 | |||
79 | @c FIXME: This is questionable, it feels like bike shed painging to do | ||
80 | @c this for several k lines. It only helps to jump between sentences in | ||
81 | @c editors afaik. | ||
82 | @c @item Use 2 spaces between sentences, so instead of: | ||
83 | |||
84 | @c @example | ||
85 | @c We do this and the other thing. This is done by foo. | ||
86 | @c @end example | ||
87 | |||
88 | @c Write: | ||
89 | |||
90 | @c @example | ||
91 | @c We do this and the other thing. This is done by foo. | ||
92 | @c @end example | ||
93 | |||
94 | @item Use @@footnote@{@} instead of putting an @@*ref@{@} to the | ||
95 | footnote on a collected footnote-page. | ||
96 | In a 200+ pages handbook it's better to have footnotes accessible | ||
97 | without having to skip over to the end. | ||
98 | |||
99 | @item Avoid unnecessary footnotes, keep the text self-explanatory and | ||
100 | in a simple language where possible/necessary. | ||
101 | |||
102 | @end itemize | ||
diff --git a/doc/documentation/chapters/developer.texi b/doc/documentation/chapters/developer.texi new file mode 100644 index 000000000..70fd7c7eb --- /dev/null +++ b/doc/documentation/chapters/developer.texi | |||
@@ -0,0 +1,8341 @@ | |||
1 | @c *********************************************************************** | ||
2 | @node GNUnet Developer Handbook | ||
3 | @chapter GNUnet Developer Handbook | ||
4 | |||
5 | This book is intended to be an introduction for programmers that want to | ||
6 | extend the GNUnet framework. GNUnet is more than a simple peer-to-peer | ||
7 | application. | ||
8 | |||
9 | For developers, GNUnet is: | ||
10 | |||
11 | @itemize @bullet | ||
12 | @item developed by a community that believes in the GNU philosophy | ||
13 | @item Free Software (Free as in Freedom), licensed under the | ||
14 | GNU General Public License | ||
15 | @item A set of standards, including coding conventions and | ||
16 | architectural rules | ||
17 | @item A set of layered protocols, both specifying the communication | ||
18 | between peers as well as the communication between components | ||
19 | of a single peer | ||
20 | @item A set of libraries with well-defined APIs suitable for | ||
21 | writing extensions | ||
22 | @end itemize | ||
23 | |||
24 | In particular, the architecture specifies that a peer consists of many | ||
25 | processes communicating via protocols. Processes can be written in almost | ||
26 | any language. | ||
27 | C and Java @footnote{As well as Guile} APIs exist for accessing existing | ||
28 | services and for writing extensions. | ||
29 | It is possible to write extensions in other languages by | ||
30 | implementing the necessary IPC protocols. | ||
31 | |||
32 | GNUnet can be extended and improved along many possible dimensions, and | ||
33 | anyone interested in Free Software and Freedom-enhancing Networking is | ||
34 | welcome to join the effort. This Developer Handbook attempts to provide | ||
35 | an initial introduction to some of the key design choices and central | ||
36 | components of the system. | ||
37 | This part of the GNUNet documentation is far from complete, | ||
38 | and we welcome informed contributions, be it in the form of | ||
39 | new chapters, sections or insightful comments. | ||
40 | |||
41 | @menu | ||
42 | * Developer Introduction:: | ||
43 | * Code overview:: | ||
44 | * System Architecture:: | ||
45 | * Subsystem stability:: | ||
46 | * Naming conventions and coding style guide:: | ||
47 | * Build-system:: | ||
48 | * Developing extensions for GNUnet using the gnunet-ext template:: | ||
49 | * Writing testcases:: | ||
50 | * TESTING library:: | ||
51 | * Performance regression analysis with Gauger:: | ||
52 | * TESTBED Subsystem:: | ||
53 | * libgnunetutil:: | ||
54 | * Automatic Restart Manager (ARM):: | ||
55 | * TRANSPORT Subsystem:: | ||
56 | * NAT library:: | ||
57 | * Distance-Vector plugin:: | ||
58 | * SMTP plugin:: | ||
59 | * Bluetooth plugin:: | ||
60 | * WLAN plugin:: | ||
61 | * ATS Subsystem:: | ||
62 | * CORE Subsystem:: | ||
63 | * CADET Subsystem:: | ||
64 | * NSE Subsystem:: | ||
65 | * HOSTLIST Subsystem:: | ||
66 | * IDENTITY Subsystem:: | ||
67 | * NAMESTORE Subsystem:: | ||
68 | * PEERINFO Subsystem:: | ||
69 | * PEERSTORE Subsystem:: | ||
70 | * SET Subsystem:: | ||
71 | * STATISTICS Subsystem:: | ||
72 | * Distributed Hash Table (DHT):: | ||
73 | * GNU Name System (GNS):: | ||
74 | * GNS Namecache:: | ||
75 | * REVOCATION Subsystem:: | ||
76 | * File-sharing (FS) Subsystem:: | ||
77 | * REGEX Subsystem:: | ||
78 | @end menu | ||
79 | |||
80 | @node Developer Introduction | ||
81 | @section Developer Introduction | ||
82 | |||
83 | This Developer Handbook is intended as first introduction to GNUnet for | ||
84 | new developers that want to extend the GNUnet framework. After the | ||
85 | introduction, each of the GNUnet subsystems (directories in the | ||
86 | @file{src/} tree) is (supposed to be) covered in its own chapter. In | ||
87 | addition to this documentation, GNUnet developers should be aware of the | ||
88 | services available on the GNUnet server to them. | ||
89 | |||
90 | New developers can have a look a the GNUnet tutorials for C and java | ||
91 | available in the @file{src/} directory of the repository or under the | ||
92 | following links: | ||
93 | |||
94 | @c ** FIXME: Link to files in source, not online. | ||
95 | @c ** FIXME: Where is the Java tutorial? | ||
96 | @itemize @bullet | ||
97 | @item @uref{https://gnunet.org/git/gnunet.git/plain/doc/gnunet-c-tutorial.pdf, GNUnet C tutorial} | ||
98 | @item GNUnet Java tutorial | ||
99 | @end itemize | ||
100 | |||
101 | In addition to the GNUnet Reference Documentation you are reading, | ||
102 | the GNUnet server at @uref{https://gnunet.org} contains | ||
103 | various resources for GNUnet developers and those | ||
104 | who aspire to become regular contributors. | ||
105 | They are all conveniently reachable via the "Developer" | ||
106 | entry in the navigation menu. Some additional tools (such as static | ||
107 | analysis reports) require a special developer access to perform certain | ||
108 | operations. If you want (or require) access, you should contact | ||
109 | @uref{http://grothoff.org/christian/, Christian Grothoff}, | ||
110 | GNUnet's maintainer. | ||
111 | |||
112 | The public subsystems on the GNUnet server that help developers are: | ||
113 | |||
114 | @itemize @bullet | ||
115 | |||
116 | @item The version control system (git) keeps our code and enables | ||
117 | distributed development. | ||
118 | It is pubclicly accessible at @uref{https://gnunet.org/git/}. | ||
119 | Only developers with write access can commit code, everyone else is | ||
120 | encouraged to submit patches to the | ||
121 | @uref{https://lists.gnu.org/mailman/listinfo/gnunet-developers, GNUnet-developers mailinglist}. | ||
122 | |||
123 | @item The bugtracking system (Mantis). | ||
124 | We use it to track feature requests, open bug reports and their | ||
125 | resolutions. | ||
126 | It can be accessed at @uref{https://gnunet.org/bugs/}. | ||
127 | Anyone can report bugs, but only developers can claim to have fixed them. | ||
128 | |||
129 | @item Our site installation of the | ||
130 | CI@footnote{Continuous Integration} system @code{Buildbot} is used | ||
131 | to check GNUnet builds automatically on a range of platforms. | ||
132 | The web interface of this CI is exposed at | ||
133 | @uref{https://gnunet.org/buildbot/}. | ||
134 | Builds are triggered automatically 30 minutes after the last commit to | ||
135 | our repository was made. | ||
136 | |||
137 | @item The current quality of our automated test suite is assessed using | ||
138 | Code coverage analysis. This analysis is run daily; however the webpage | ||
139 | is only updated if all automated tests pass at that time. Testcases that | ||
140 | improve our code coverage are always welcome. | ||
141 | |||
142 | @item We try to automatically find bugs using a static analysis scan. | ||
143 | This scan is run daily; however the webpage is only updated if all | ||
144 | automated tests pass at the time. Note that not everything that is | ||
145 | flagged by the analysis is a bug, sometimes even good code can be marked | ||
146 | as possibly problematic. Nevertheless, developers are encouraged to at | ||
147 | least be aware of all issues in their code that are listed. | ||
148 | |||
149 | @item We use Gauger for automatic performance regression visualization. | ||
150 | Details on how to use Gauger are here. | ||
151 | |||
152 | @item We use @uref{http://junit.org/, junit} to automatically test | ||
153 | @command{gnunet-java}. | ||
154 | Automatically generated, current reports on the test suite are here. | ||
155 | |||
156 | @item We use Cobertura to generate test coverage reports for gnunet-java. | ||
157 | Current reports on test coverage are here. | ||
158 | |||
159 | @end itemize | ||
160 | |||
161 | |||
162 | |||
163 | @c *********************************************************************** | ||
164 | @menu | ||
165 | * Project overview:: | ||
166 | @end menu | ||
167 | |||
168 | @node Project overview | ||
169 | @subsection Project overview | ||
170 | |||
171 | The GNUnet project consists at this point of several sub-projects. This | ||
172 | section is supposed to give an initial overview about the various | ||
173 | sub-projects. Note that this description also lists projects that are far | ||
174 | from complete, including even those that have literally not a single line | ||
175 | of code in them yet. | ||
176 | |||
177 | GNUnet sub-projects in order of likely relevance are currently: | ||
178 | |||
179 | @table @asis | ||
180 | |||
181 | @item @command{gnunet} | ||
182 | Core of the P2P framework, including file-sharing, VPN and | ||
183 | chat applications; this is what the Developer Handbook covers mostly | ||
184 | @item @command{gnunet-gtk} | ||
185 | Gtk+-based user interfaces, including: | ||
186 | |||
187 | @itemize @bullet | ||
188 | @item @command{gnunet-fs-gtk} (file-sharing), | ||
189 | @item @command{gnunet-statistics-gtk} (statistics over time), | ||
190 | @item @command{gnunet-peerinfo-gtk} | ||
191 | (information about current connections and known peers), | ||
192 | @item @command{gnunet-chat-gtk} (chat GUI) and | ||
193 | @item @command{gnunet-setup} (setup tool for "everything") | ||
194 | @end itemize | ||
195 | |||
196 | @item @command{gnunet-fuse} | ||
197 | Mounting directories shared via GNUnet's file-sharing | ||
198 | on GNU/Linux distributions | ||
199 | @item @command{gnunet-update} | ||
200 | Installation and update tool | ||
201 | @item @command{gnunet-ext} | ||
202 | Template for starting 'external' GNUnet projects | ||
203 | @item @command{gnunet-java} | ||
204 | Java APIs for writing GNUnet services and applications | ||
205 | @c ** FIXME: Point to new website repository once we have it: | ||
206 | @c ** @item svn/gnunet-www/ Code and media helping drive the GNUnet | ||
207 | @c website | ||
208 | @item @command{eclectic} | ||
209 | Code to run GNUnet nodes on testbeds for research, development, | ||
210 | testing and evaluation | ||
211 | @c ** FIXME: Solve the status and location of gnunet-qt | ||
212 | @item @command{gnunet-qt} | ||
213 | Qt-based GNUnet GUI (is it depreacated?) | ||
214 | @item @command{gnunet-cocoa} | ||
215 | cocoa-based GNUnet GUI (is it depreacated?) | ||
216 | @item @command{gnunet-guile} | ||
217 | |||
218 | @end table | ||
219 | |||
220 | We are also working on various supporting libraries and tools: | ||
221 | @c ** FIXME: What about gauger, and what about libmwmodem? | ||
222 | |||
223 | @table @asis | ||
224 | @item @command{libextractor} | ||
225 | GNU libextractor (meta data extraction) | ||
226 | @item @command{libmicrohttpd} | ||
227 | GNU libmicrohttpd (embedded HTTP(S) server library) | ||
228 | @item @command{gauger} | ||
229 | Tool for performance regression analysis | ||
230 | @item @command{monkey} | ||
231 | Tool for automated debugging of distributed systems | ||
232 | @item @command{libmwmodem} | ||
233 | Library for accessing satellite connection quality | ||
234 | reports | ||
235 | @item @command{libgnurl} | ||
236 | gnURL (feature-restricted variant of cURL/libcurl) | ||
237 | @end table | ||
238 | |||
239 | Finally, there are various external projects (see links for a list of | ||
240 | those that have a public website) which build on top of the GNUnet | ||
241 | framework. | ||
242 | |||
243 | @c *********************************************************************** | ||
244 | @node Code overview | ||
245 | @section Code overview | ||
246 | |||
247 | This section gives a brief overview of the GNUnet source code. | ||
248 | Specifically, we sketch the function of each of the subdirectories in | ||
249 | the @file{gnunet/src/} directory. The order given is roughly bottom-up | ||
250 | (in terms of the layers of the system). | ||
251 | |||
252 | @table @asis | ||
253 | @item @file{util/} --- libgnunetutil | ||
254 | Library with general utility functions, all | ||
255 | GNUnet binaries link against this library. Anything from memory | ||
256 | allocation and data structures to cryptography and inter-process | ||
257 | communication. The goal is to provide an OS-independent interface and | ||
258 | more 'secure' or convenient implementations of commonly used primitives. | ||
259 | The API is spread over more than a dozen headers, developers should study | ||
260 | those closely to avoid duplicating existing functions. | ||
261 | @pxref{libgnunetutil}. | ||
262 | @item @file{hello/} --- libgnunethello | ||
263 | HELLO messages are used to | ||
264 | describe under which addresses a peer can be reached (for example, | ||
265 | protocol, IP, port). This library manages parsing and generating of HELLO | ||
266 | messages. | ||
267 | @item @file{block/} --- libgnunetblock | ||
268 | The DHT and other components of GNUnet | ||
269 | store information in units called 'blocks'. Each block has a type and the | ||
270 | type defines a particular format and how that binary format is to be | ||
271 | linked to a hash code (the key for the DHT and for databases). The block | ||
272 | library is a wapper around block plugins which provide the necessary | ||
273 | functions for each block type. | ||
274 | @item @file{statistics/} --- statistics service | ||
275 | The statistics service enables associating | ||
276 | values (of type uint64_t) with a componenet name and a string. The main | ||
277 | uses is debugging (counting events), performance tracking and user | ||
278 | entertainment (what did my peer do today?). | ||
279 | @item @file{arm/} --- Automatic Restart Manager (ARM) | ||
280 | The automatic-restart-manager (ARM) service | ||
281 | is the GNUnet master service. Its role is to start gnunet-services, to | ||
282 | re-start them when they crashed and finally to shut down the system when | ||
283 | requested. | ||
284 | @item @file{peerinfo/} --- peerinfo service | ||
285 | The peerinfo service keeps track of which peers are known | ||
286 | to the local peer and also tracks the validated addresses for each peer | ||
287 | (in the form of a HELLO message) for each of those peers. The peer is not | ||
288 | necessarily connected to all peers known to the peerinfo service. | ||
289 | Peerinfo provides persistent storage for peer identities --- peers are | ||
290 | not forgotten just because of a system restart. | ||
291 | @item @file{datacache/} --- libgnunetdatacache | ||
292 | The datacache library provides (temporary) block storage for the DHT. | ||
293 | Existing plugins can store blocks in Sqlite, Postgres or MySQL databases. | ||
294 | All data stored in the cache is lost when the peer is stopped or | ||
295 | restarted (datacache uses temporary tables). | ||
296 | @item @file{datastore/} --- datastore service | ||
297 | The datastore service stores file-sharing blocks in | ||
298 | databases for extended periods of time. In contrast to the datacache, data | ||
299 | is not lost when peers restart. However, quota restrictions may still | ||
300 | cause old, expired or low-priority data to be eventually discarded. | ||
301 | Existing plugins can store blocks in Sqlite, Postgres or MySQL databases. | ||
302 | @item @file{template/} --- service template | ||
303 | Template for writing a new service. Does nothing. | ||
304 | @item @file{ats/} --- Automatic Transport Selection | ||
305 | The automatic transport selection (ATS) service | ||
306 | is responsible for deciding which address (i.e. | ||
307 | which transport plugin) should be used for communication with other peers, | ||
308 | and at what bandwidth. | ||
309 | @item @file{nat/} --- libgnunetnat | ||
310 | Library that provides basic functions for NAT traversal. | ||
311 | The library supports NAT traversal with | ||
312 | manual hole-punching by the user, UPnP and ICMP-based autonomous NAT | ||
313 | traversal. The library also includes an API for testing if the current | ||
314 | configuration works and the @code{gnunet-nat-server} which provides an | ||
315 | external service to test the local configuration. | ||
316 | @item @file{fragmentation/} --- libgnunetfragmentation | ||
317 | Some transports (UDP and WLAN, mostly) have restrictions on the maximum | ||
318 | transfer unit (MTU) for packets. The fragmentation library can be used to | ||
319 | break larger packets into chunks of at most 1k and transmit the resulting | ||
320 | fragments reliabily (with acknowledgement, retransmission, timeouts, | ||
321 | etc.). | ||
322 | @item @file{transport/} --- transport service | ||
323 | The transport service is responsible for managing the | ||
324 | basic P2P communication. It uses plugins to support P2P communication | ||
325 | over TCP, UDP, HTTP, HTTPS and other protocols.The transport service | ||
326 | validates peer addresses, enforces bandwidth restrictions, limits the | ||
327 | total number of connections and enforces connectivity restrictions (i.e. | ||
328 | friends-only). | ||
329 | @item @file{peerinfo-tool/} --- gnunet-peerinfo | ||
330 | This directory contains the gnunet-peerinfo binary which can be used to | ||
331 | inspect the peers and HELLOs known to the peerinfo service. | ||
332 | @item @file{core/} | ||
333 | The core service is responsible for establishing encrypted, authenticated | ||
334 | connections with other peers, encrypting and decrypting messages and | ||
335 | forwarding messages to higher-level services that are interested in them. | ||
336 | @item @file{testing/} --- libgnunettesting | ||
337 | The testing library allows starting (and stopping) peers | ||
338 | for writing testcases. | ||
339 | It also supports automatic generation of configurations for peers | ||
340 | ensuring that the ports and paths are disjoint. libgnunettesting is also | ||
341 | the foundation for the testbed service | ||
342 | @item @file{testbed/} --- testbed service | ||
343 | The testbed service is used for creating small or large scale deployments | ||
344 | of GNUnet peers for evaluation of protocols. | ||
345 | It facilitates peer depolyments on multiple | ||
346 | hosts (for example, in a cluster) and establishing varous network | ||
347 | topologies (both underlay and overlay). | ||
348 | @item @file{nse/} --- Network Size Estimation | ||
349 | The network size estimation (NSE) service | ||
350 | implements a protocol for (securely) estimating the current size of the | ||
351 | P2P network. | ||
352 | @item @file{dht/} --- distributed hash table | ||
353 | The distributed hash table (DHT) service provides a | ||
354 | distributed implementation of a hash table to store blocks under hash | ||
355 | keys in the P2P network. | ||
356 | @item @file{hostlist/} --- hostlist service | ||
357 | The hostlist service allows learning about | ||
358 | other peers in the network by downloading HELLO messages from an HTTP | ||
359 | server, can be configured to run such an HTTP server and also implements | ||
360 | a P2P protocol to advertise and automatically learn about other peers | ||
361 | that offer a public hostlist server. | ||
362 | @item @file{topology/} --- topology service | ||
363 | The topology service is responsible for | ||
364 | maintaining the mesh topology. It tries to maintain connections to friends | ||
365 | (depending on the configuration) and also tries to ensure that the peer | ||
366 | has a decent number of active connections at all times. If necessary, new | ||
367 | connections are added. All peers should run the topology service, | ||
368 | otherwise they may end up not being connected to any other peer (unless | ||
369 | some other service ensures that core establishes the required | ||
370 | connections). The topology service also tells the transport service which | ||
371 | connections are permitted (for friend-to-friend networking) | ||
372 | @item @file{fs/} --- file-sharing | ||
373 | The file-sharing (FS) service implements GNUnet's | ||
374 | file-sharing application. Both anonymous file-sharing (using gap) and | ||
375 | non-anonymous file-sharing (using dht) are supported. | ||
376 | @item @file{cadet/} --- cadet service | ||
377 | The CADET service provides a general-purpose routing abstraction to create | ||
378 | end-to-end encrypted tunnels in mesh networks. We wrote a paper | ||
379 | documenting key aspects of the design. | ||
380 | @item @file{tun/} --- libgnunettun | ||
381 | Library for building IPv4, IPv6 packets and creating | ||
382 | checksums for UDP, TCP and ICMP packets. The header | ||
383 | defines C structs for common Internet packet formats and in particular | ||
384 | structs for interacting with TUN (virtual network) interfaces. | ||
385 | @item @file{mysql/} --- libgnunetmysql | ||
386 | Library for creating and executing prepared MySQL | ||
387 | statements and to manage the connection to the MySQL database. | ||
388 | Essentially a lightweight wrapper for the interaction between GNUnet | ||
389 | components and libmysqlclient. | ||
390 | @item @file{dns/} | ||
391 | Service that allows intercepting and modifying DNS requests of | ||
392 | the local machine. Currently used for IPv4-IPv6 protocol translation | ||
393 | (DNS-ALG) as implemented by "pt/" and for the GNUnet naming system. The | ||
394 | service can also be configured to offer an exit service for DNS traffic. | ||
395 | @item @file{vpn/} --- VPN service | ||
396 | The virtual public network (VPN) service provides a virtual | ||
397 | tunnel interface (VTUN) for IP routing over GNUnet. | ||
398 | Needs some other peers to run an "exit" service to work. | ||
399 | Can be activated using the "gnunet-vpn" tool or integrated with DNS using | ||
400 | the "pt" daemon. | ||
401 | @item @file{exit/} | ||
402 | Daemon to allow traffic from the VPN to exit this | ||
403 | peer to the Internet or to specific IP-based services of the local peer. | ||
404 | Currently, an exit service can only be restricted to IPv4 or IPv6, not to | ||
405 | specific ports and or IP address ranges. If this is not acceptable, | ||
406 | additional firewall rules must be added manually. exit currently only | ||
407 | works for normal UDP, TCP and ICMP traffic; DNS queries need to leave the | ||
408 | system via a DNS service. | ||
409 | @item @file{pt/} | ||
410 | protocol translation daemon. This daemon enables 4-to-6, | ||
411 | 6-to-4, 4-over-6 or 6-over-4 transitions for the local system. It | ||
412 | essentially uses "DNS" to intercept DNS replies and then maps results to | ||
413 | those offered by the VPN, which then sends them using mesh to some daemon | ||
414 | offering an appropriate exit service. | ||
415 | @item @file{identity/} | ||
416 | Management of egos (alter egos) of a user; identities are | ||
417 | essentially named ECC private keys and used for zones in the GNU name | ||
418 | system and for namespaces in file-sharing, but might find other uses later | ||
419 | @item @file{revocation/} | ||
420 | Key revocation service, can be used to revoke the | ||
421 | private key of an identity if it has been compromised | ||
422 | @item @file{namecache/} | ||
423 | Cache for resolution results for the GNU name system; | ||
424 | data is encrypted and can be shared among users, | ||
425 | loss of the data should ideally only result in a | ||
426 | performance degradation (persistence not required) | ||
427 | @item @file{namestore/} | ||
428 | Database for the GNU name system with per-user private information, | ||
429 | persistence required | ||
430 | @item @file{gns/} | ||
431 | GNU name system, a GNU approach to DNS and PKI. | ||
432 | @item @file{dv/} | ||
433 | A plugin for distance-vector (DV)-based routing. | ||
434 | DV consists of a service and a transport plugin to provide peers | ||
435 | with the illusion of a direct P2P connection for connections | ||
436 | that use multiple (typically up to 3) hops in the actual underlay network. | ||
437 | @item @file{regex/} | ||
438 | Service for the (distributed) evaluation of regular expressions. | ||
439 | @item @file{scalarproduct/} | ||
440 | The scalar product service offers an API to perform a secure multiparty | ||
441 | computation which calculates a scalar product between two peers | ||
442 | without exposing the private input vectors of the peers to each other. | ||
443 | @item @file{consensus/} | ||
444 | The consensus service will allow a set of peers to agree | ||
445 | on a set of values via a distributed set union computation. | ||
446 | @item @file{rest/} | ||
447 | The rest API allows access to GNUnet services using RESTful interaction. | ||
448 | The services provide plugins that can exposed by the rest server. | ||
449 | @item @file{experimentation/} | ||
450 | The experimentation daemon coordinates distributed | ||
451 | experimentation to evaluate transport and ATS properties. | ||
452 | @end table | ||
453 | |||
454 | @c *********************************************************************** | ||
455 | @node System Architecture | ||
456 | @section System Architecture | ||
457 | |||
458 | GNUnet developers like LEGOs. The blocks are indestructible, can be | ||
459 | stacked together to construct complex buildings and it is generally easy | ||
460 | to swap one block for a different one that has the same shape. GNUnet's | ||
461 | architecture is based on LEGOs: | ||
462 | |||
463 | @c images here | ||
464 | |||
465 | This chapter documents the GNUnet LEGO system, also known as GNUnet's | ||
466 | system architecture. | ||
467 | |||
468 | The most common GNUnet component is a service. Services offer an API (or | ||
469 | several, depending on what you count as "an API") which is implemented as | ||
470 | a library. The library communicates with the main process of the service | ||
471 | using a service-specific network protocol. The main process of the service | ||
472 | typically doesn't fully provide everything that is needed --- it has holes | ||
473 | to be filled by APIs to other services. | ||
474 | |||
475 | A special kind of component in GNUnet are user interfaces and daemons. | ||
476 | Like services, they have holes to be filled by APIs of other services. | ||
477 | Unlike services, daemons do not implement their own network protocol and | ||
478 | they have no API: | ||
479 | |||
480 | The GNUnet system provides a range of services, daemons and user | ||
481 | interfaces, which are then combined into a layered GNUnet instance (also | ||
482 | known as a peer). | ||
483 | |||
484 | Note that while it is generally possible to swap one service for another | ||
485 | compatible service, there is often only one implementation. However, | ||
486 | during development we often have a "new" version of a service in parallel | ||
487 | with an "old" version. While the "new" version is not working, developers | ||
488 | working on other parts of the service can continue their development by | ||
489 | simply using the "old" service. Alternative design ideas can also be | ||
490 | easily investigated by swapping out individual components. This is | ||
491 | typically achieved by simply changing the name of the "BINARY" in the | ||
492 | respective configuration section. | ||
493 | |||
494 | Key properties of GNUnet services are that they must be separate | ||
495 | processes and that they must protect themselves by applying tight error | ||
496 | checking against the network protocol they implement (thereby achieving a | ||
497 | certain degree of robustness). | ||
498 | |||
499 | On the other hand, the APIs are implemented to tolerate failures of the | ||
500 | service, isolating their host process from errors by the service. If the | ||
501 | service process crashes, other services and daemons around it should not | ||
502 | also fail, but instead wait for the service process to be restarted by | ||
503 | ARM. | ||
504 | |||
505 | |||
506 | @c *********************************************************************** | ||
507 | @node Subsystem stability | ||
508 | @section Subsystem stability | ||
509 | |||
510 | This section documents the current stability of the various GNUnet | ||
511 | subsystems. Stability here describes the expected degree of compatibility | ||
512 | with future versions of GNUnet. For each subsystem we distinguish between | ||
513 | compatibility on the P2P network level (communication protocol between | ||
514 | peers), the IPC level (communication between the service and the service | ||
515 | library) and the API level (stability of the API). P2P compatibility is | ||
516 | relevant in terms of which applications are likely going to be able to | ||
517 | communicate with future versions of the network. IPC communication is | ||
518 | relevant for the implementation of language bindings that re-implement the | ||
519 | IPC messages. Finally, API compatibility is relevant to developers that | ||
520 | hope to be able to avoid changes to applications build on top of the APIs | ||
521 | of the framework. | ||
522 | |||
523 | The following table summarizes our current view of the stability of the | ||
524 | respective protocols or APIs: | ||
525 | |||
526 | @multitable @columnfractions .20 .20 .20 .20 | ||
527 | @headitem Subsystem @tab P2P @tab IPC @tab C API | ||
528 | @item util @tab n/a @tab n/a @tab stable | ||
529 | @item arm @tab n/a @tab stable @tab stable | ||
530 | @item ats @tab n/a @tab unstable @tab testing | ||
531 | @item block @tab n/a @tab n/a @tab stable | ||
532 | @item cadet @tab testing @tab testing @tab testing | ||
533 | @item consensus @tab experimental @tab experimental @tab experimental | ||
534 | @item core @tab stable @tab stable @tab stable | ||
535 | @item datacache @tab n/a @tab n/a @tab stable | ||
536 | @item datastore @tab n/a @tab stable @tab stable | ||
537 | @item dht @tab stable @tab stable @tab stable | ||
538 | @item dns @tab stable @tab stable @tab stable | ||
539 | @item dv @tab testing @tab testing @tab n/a | ||
540 | @item exit @tab testing @tab n/a @tab n/a | ||
541 | @item fragmentation @tab stable @tab n/a @tab stable | ||
542 | @item fs @tab stable @tab stable @tab stable | ||
543 | @item gns @tab stable @tab stable @tab stable | ||
544 | @item hello @tab n/a @tab n/a @tab testing | ||
545 | @item hostlist @tab stable @tab stable @tab n/a | ||
546 | @item identity @tab stable @tab stable @tab n/a | ||
547 | @item multicast @tab experimental @tab experimental @tab experimental | ||
548 | @item mysql @tab stable @tab n/a @tab stable | ||
549 | @item namestore @tab n/a @tab stable @tab stable | ||
550 | @item nat @tab n/a @tab n/a @tab stable | ||
551 | @item nse @tab stable @tab stable @tab stable | ||
552 | @item peerinfo @tab n/a @tab stable @tab stable | ||
553 | @item psyc @tab experimental @tab experimental @tab experimental | ||
554 | @item pt @tab n/a @tab n/a @tab n/a | ||
555 | @item regex @tab stable @tab stable @tab stable | ||
556 | @item revocation @tab stable @tab stable @tab stable | ||
557 | @item social @tab experimental @tab experimental @tab experimental | ||
558 | @item statistics @tab n/a @tab stable @tab stable | ||
559 | @item testbed @tab n/a @tab testing @tab testing | ||
560 | @item testing @tab n/a @tab n/a @tab testing | ||
561 | @item topology @tab n/a @tab n/a @tab n/a | ||
562 | @item transport @tab stable @tab stable @tab stable | ||
563 | @item tun @tab n/a @tab n/a @tab stable | ||
564 | @item vpn @tab testing @tab n/a @tab n/a | ||
565 | @end multitable | ||
566 | |||
567 | Here is a rough explanation of the values: | ||
568 | |||
569 | @table @samp | ||
570 | @item stable | ||
571 | No incompatible changes are planned at this time; for IPC/APIs, if | ||
572 | there are incompatible changes, they will be minor and might only require | ||
573 | minimal changes to existing code; for P2P, changes will be avoided if at | ||
574 | all possible for the 0.10.x-series | ||
575 | |||
576 | @item testing | ||
577 | No incompatible changes are | ||
578 | planned at this time, but the code is still known to be in flux; so while | ||
579 | we have no concrete plans, our expectation is that there will still be | ||
580 | minor modifications; for P2P, changes will likely be extensions that | ||
581 | should not break existing code | ||
582 | |||
583 | @item unstable | ||
584 | Changes are planned and will happen; however, they | ||
585 | will not be totally radical and the result should still resemble what is | ||
586 | there now; nevertheless, anticipated changes will break protocol/API | ||
587 | compatibility | ||
588 | |||
589 | @item experimental | ||
590 | Changes are planned and the result may look nothing like | ||
591 | what the API/protocol looks like today | ||
592 | |||
593 | @item unknown | ||
594 | Someone should think about where this subsystem headed | ||
595 | |||
596 | @item n/a | ||
597 | This subsystem does not have an API/IPC-protocol/P2P-protocol | ||
598 | @end table | ||
599 | |||
600 | @c *********************************************************************** | ||
601 | @node Naming conventions and coding style guide | ||
602 | @section Naming conventions and coding style guide | ||
603 | |||
604 | Here you can find some rules to help you write code for GNUnet. | ||
605 | |||
606 | @c *********************************************************************** | ||
607 | @menu | ||
608 | * Naming conventions:: | ||
609 | * Coding style:: | ||
610 | @end menu | ||
611 | |||
612 | @node Naming conventions | ||
613 | @subsection Naming conventions | ||
614 | |||
615 | |||
616 | @c *********************************************************************** | ||
617 | @menu | ||
618 | * include files:: | ||
619 | * binaries:: | ||
620 | * logging:: | ||
621 | * configuration:: | ||
622 | * exported symbols:: | ||
623 | * private (library-internal) symbols (including structs and macros):: | ||
624 | * testcases:: | ||
625 | * performance tests:: | ||
626 | * src/ directories:: | ||
627 | @end menu | ||
628 | |||
629 | @node include files | ||
630 | @subsubsection include files | ||
631 | |||
632 | @itemize @bullet | ||
633 | @item _lib: library without need for a process | ||
634 | @item _service: library that needs a service process | ||
635 | @item _plugin: plugin definition | ||
636 | @item _protocol: structs used in network protocol | ||
637 | @item exceptions: | ||
638 | @itemize @bullet | ||
639 | @item gnunet_config.h --- generated | ||
640 | @item platform.h --- first included | ||
641 | @item plibc.h --- external library | ||
642 | @item gnunet_common.h --- fundamental routines | ||
643 | @item gnunet_directories.h --- generated | ||
644 | @item gettext.h --- external library | ||
645 | @end itemize | ||
646 | @end itemize | ||
647 | |||
648 | @c *********************************************************************** | ||
649 | @node binaries | ||
650 | @subsubsection binaries | ||
651 | |||
652 | @itemize @bullet | ||
653 | @item gnunet-service-xxx: service process (has listen socket) | ||
654 | @item gnunet-daemon-xxx: daemon process (no listen socket) | ||
655 | @item gnunet-helper-xxx[-yyy]: SUID helper for module xxx | ||
656 | @item gnunet-yyy: command-line tool for end-users | ||
657 | @item libgnunet_plugin_xxx_yyy.so: plugin for API xxx | ||
658 | @item libgnunetxxx.so: library for API xxx | ||
659 | @end itemize | ||
660 | |||
661 | @c *********************************************************************** | ||
662 | @node logging | ||
663 | @subsubsection logging | ||
664 | |||
665 | @itemize @bullet | ||
666 | @item services and daemons use their directory name in | ||
667 | @code{GNUNET_log_setup} (i.e. 'core') and log using | ||
668 | plain 'GNUNET_log'. | ||
669 | @item command-line tools use their full name in | ||
670 | @code{GNUNET_log_setup} (i.e. 'gnunet-publish') and log using | ||
671 | plain 'GNUNET_log'. | ||
672 | @item service access libraries log using | ||
673 | '@code{GNUNET_log_from}' and use '@code{DIRNAME-api}' for the | ||
674 | component (i.e. 'core-api') | ||
675 | @item pure libraries (without associated service) use | ||
676 | '@code{GNUNET_log_from}' with the component set to their | ||
677 | library name (without lib or '@file{.so}'), | ||
678 | which should also be their directory name (i.e. '@file{nat}') | ||
679 | @item plugins should use '@code{GNUNET_log_from}' | ||
680 | with the directory name and the plugin name combined to produce | ||
681 | the component name (i.e. 'transport-tcp'). | ||
682 | @item logging should be unified per-file by defining a | ||
683 | @code{LOG} macro with the appropriate arguments, | ||
684 | along these lines: | ||
685 | |||
686 | @example | ||
687 | #define LOG(kind,...) | ||
688 | GNUNET_log_from (kind, "example-api",__VA_ARGS__) | ||
689 | @end example | ||
690 | |||
691 | @end itemize | ||
692 | |||
693 | @c *********************************************************************** | ||
694 | @node configuration | ||
695 | @subsubsection configuration | ||
696 | |||
697 | @itemize @bullet | ||
698 | @item paths (that are substituted in all filenames) are in PATHS | ||
699 | (have as few as possible) | ||
700 | @item all options for a particular module (@file{src/MODULE}) | ||
701 | are under @code{[MODULE]} | ||
702 | @item options for a plugin of a module | ||
703 | are under @code{[MODULE-PLUGINNAME]} | ||
704 | @end itemize | ||
705 | |||
706 | @c *********************************************************************** | ||
707 | @node exported symbols | ||
708 | @subsubsection exported symbols | ||
709 | |||
710 | @itemize @bullet | ||
711 | @item must start with @code{GNUNET_modulename_} and be defined in | ||
712 | @file{modulename.c} | ||
713 | @item exceptions: those defined in @file{gnunet_common.h} | ||
714 | @end itemize | ||
715 | |||
716 | @c *********************************************************************** | ||
717 | @node private (library-internal) symbols (including structs and macros) | ||
718 | @subsubsection private (library-internal) symbols (including structs and macros) | ||
719 | |||
720 | @itemize @bullet | ||
721 | @item must NOT start with any prefix | ||
722 | @item must not be exported in a way that linkers could use them or@ other | ||
723 | libraries might see them via headers; they must be either | ||
724 | declared/defined in C source files or in headers that are in the | ||
725 | respective directory under @file{src/modulename/} and NEVER be declared | ||
726 | in @file{src/include/}. | ||
727 | @end itemize | ||
728 | |||
729 | @node testcases | ||
730 | @subsubsection testcases | ||
731 | |||
732 | @itemize @bullet | ||
733 | @item must be called @file{test_module-under-test_case-description.c} | ||
734 | @item "case-description" maybe omitted if there is only one test | ||
735 | @end itemize | ||
736 | |||
737 | @c *********************************************************************** | ||
738 | @node performance tests | ||
739 | @subsubsection performance tests | ||
740 | |||
741 | @itemize @bullet | ||
742 | @item must be called @file{perf_module-under-test_case-description.c} | ||
743 | @item "case-description" maybe omitted if there is only one performance | ||
744 | test | ||
745 | @item Must only be run if @code{HAVE_BENCHMARKS} is satisfied | ||
746 | @end itemize | ||
747 | |||
748 | @c *********************************************************************** | ||
749 | @node src/ directories | ||
750 | @subsubsection src/ directories | ||
751 | |||
752 | @itemize @bullet | ||
753 | @item gnunet-NAME: end-user applications (i.e., gnunet-search, gnunet-arm) | ||
754 | @item gnunet-service-NAME: service processes with accessor library (i.e., | ||
755 | gnunet-service-arm) | ||
756 | @item libgnunetNAME: accessor library (_service.h-header) or standalone | ||
757 | library (_lib.h-header) | ||
758 | @item gnunet-daemon-NAME: daemon process without accessor library (i.e., | ||
759 | gnunet-daemon-hostlist) and no GNUnet management port | ||
760 | @item libgnunet_plugin_DIR_NAME: loadable plugins (i.e., | ||
761 | libgnunet_plugin_transport_tcp) | ||
762 | @end itemize | ||
763 | |||
764 | @cindex Coding style | ||
765 | @node Coding style | ||
766 | @subsection Coding style | ||
767 | |||
768 | @c XXX: Adjust examples to GNU Standards! | ||
769 | @itemize @bullet | ||
770 | @item We follow the GNU Coding Standards (@pxref{Top, The GNU Coding Standards,, standards, The GNU Coding Standards}); | ||
771 | @item Indentation is done with spaces, two per level, no tabs; | ||
772 | @item C99 struct initialization is fine; | ||
773 | @item declare only one variable per line, for example: | ||
774 | |||
775 | @noindent | ||
776 | instead of | ||
777 | |||
778 | @example | ||
779 | int i,j; | ||
780 | @end example | ||
781 | |||
782 | @noindent | ||
783 | write: | ||
784 | |||
785 | @example | ||
786 | int i; | ||
787 | int j; | ||
788 | @end example | ||
789 | |||
790 | @c TODO: include actual example from a file in source | ||
791 | |||
792 | @noindent | ||
793 | This helps keep diffs small and forces developers to think precisely about | ||
794 | the type of every variable. | ||
795 | Note that @code{char *} is different from @code{const char*} and | ||
796 | @code{int} is different from @code{unsigned int} or @code{uint32_t}. | ||
797 | Each variable type should be chosen with care. | ||
798 | |||
799 | @item While @code{goto} should generally be avoided, having a | ||
800 | @code{goto} to the end of a function to a block of clean up | ||
801 | statements (free, close, etc.) can be acceptable. | ||
802 | |||
803 | @item Conditions should be written with constants on the left (to avoid | ||
804 | accidental assignment) and with the 'true' target being either the | ||
805 | 'error' case or the significantly simpler continuation. For example: | ||
806 | |||
807 | @example | ||
808 | if (0 != stat ("filename," &sbuf)) @{ | ||
809 | error(); | ||
810 | @} | ||
811 | else @{ | ||
812 | /* handle normal case here */ | ||
813 | @} | ||
814 | @end example | ||
815 | |||
816 | @noindent | ||
817 | instead of | ||
818 | |||
819 | @example | ||
820 | if (stat ("filename," &sbuf) == 0) @{ | ||
821 | /* handle normal case here */ | ||
822 | @} else @{ | ||
823 | error(); | ||
824 | @} | ||
825 | @end example | ||
826 | |||
827 | @noindent | ||
828 | If possible, the error clause should be terminated with a 'return' (or | ||
829 | 'goto' to some cleanup routine) and in this case, the 'else' clause | ||
830 | should be omitted: | ||
831 | |||
832 | @example | ||
833 | if (0 != stat ("filename," &sbuf)) @{ | ||
834 | error(); | ||
835 | return; | ||
836 | @} | ||
837 | /* handle normal case here */ | ||
838 | @end example | ||
839 | |||
840 | This serves to avoid deep nesting. The 'constants on the left' rule | ||
841 | applies to all constants (including. @code{GNUNET_SCHEDULER_NO_TASK}), | ||
842 | NULL, and enums). With the two above rules (constants on left, errors in | ||
843 | 'true' branch), there is only one way to write most branches correctly. | ||
844 | |||
845 | @item Combined assignments and tests are allowed if they do not hinder | ||
846 | code clarity. For example, one can write: | ||
847 | |||
848 | @example | ||
849 | if (NULL == (value = lookup_function())) @{ | ||
850 | error(); | ||
851 | return; | ||
852 | @} | ||
853 | @end example | ||
854 | |||
855 | @item Use @code{break} and @code{continue} wherever possible to avoid | ||
856 | deep(er) nesting. Thus, we would write: | ||
857 | |||
858 | @example | ||
859 | next = head; | ||
860 | while (NULL != (pos = next)) @{ | ||
861 | next = pos->next; | ||
862 | if (! should_free (pos)) | ||
863 | continue; | ||
864 | GNUNET_CONTAINER_DLL_remove (head, tail, pos); | ||
865 | GNUNET_free (pos); | ||
866 | @} | ||
867 | @end example | ||
868 | |||
869 | instead of | ||
870 | |||
871 | @example | ||
872 | next = head; while (NULL != (pos = next)) @{ | ||
873 | next = pos->next; | ||
874 | if (should_free (pos)) @{ | ||
875 | /* unnecessary nesting! */ | ||
876 | GNUNET_CONTAINER_DLL_remove (head, tail, pos); | ||
877 | GNUNET_free (pos); | ||
878 | @} | ||
879 | @} | ||
880 | @end example | ||
881 | |||
882 | @item We primarily use @code{for} and @code{while} loops. | ||
883 | A @code{while} loop is used if the method for advancing in the loop is | ||
884 | not a straightforward increment operation. In particular, we use: | ||
885 | |||
886 | @example | ||
887 | next = head; | ||
888 | while (NULL != (pos = next)) | ||
889 | @{ | ||
890 | next = pos->next; | ||
891 | if (! should_free (pos)) | ||
892 | continue; | ||
893 | GNUNET_CONTAINER_DLL_remove (head, tail, pos); | ||
894 | GNUNET_free (pos); | ||
895 | @} | ||
896 | @end example | ||
897 | |||
898 | to free entries in a list (as the iteration changes the structure of the | ||
899 | list due to the free; the equivalent @code{for} loop does no longer | ||
900 | follow the simple @code{for} paradigm of @code{for(INIT;TEST;INC)}). | ||
901 | However, for loops that do follow the simple @code{for} paradigm we do | ||
902 | use @code{for}, even if it involves linked lists: | ||
903 | |||
904 | @example | ||
905 | /* simple iteration over a linked list */ | ||
906 | for (pos = head; | ||
907 | NULL != pos; | ||
908 | pos = pos->next) | ||
909 | @{ | ||
910 | use (pos); | ||
911 | @} | ||
912 | @end example | ||
913 | |||
914 | |||
915 | @item The first argument to all higher-order functions in GNUnet must be | ||
916 | declared to be of type @code{void *} and is reserved for a closure. We do | ||
917 | not use inner functions, as trampolines would conflict with setups that | ||
918 | use non-executable stacks. | ||
919 | The first statement in a higher-order function, which unusually should | ||
920 | be part of the variable declarations, should assign the | ||
921 | @code{cls} argument to the precise expected type. For example: | ||
922 | |||
923 | @example | ||
924 | int callback (void *cls, char *args) @{ | ||
925 | struct Foo *foo = cls; | ||
926 | int other_variables; | ||
927 | |||
928 | /* rest of function */ | ||
929 | @} | ||
930 | @end example | ||
931 | |||
932 | |||
933 | @item It is good practice to write complex @code{if} expressions instead | ||
934 | of using deeply nested @code{if} statements. However, except for addition | ||
935 | and multiplication, all operators should use parens. This is fine: | ||
936 | |||
937 | @example | ||
938 | if ( (1 == foo) || ((0 == bar) && (x != y)) ) | ||
939 | return x; | ||
940 | @end example | ||
941 | |||
942 | |||
943 | However, this is not: | ||
944 | |||
945 | @example | ||
946 | if (1 == foo) | ||
947 | return x; | ||
948 | if (0 == bar && x != y) | ||
949 | return x; | ||
950 | @end example | ||
951 | |||
952 | @noindent | ||
953 | Note that splitting the @code{if} statement above is debateable as the | ||
954 | @code{return x} is a very trivial statement. However, once the logic after | ||
955 | the branch becomes more complicated (and is still identical), the "or" | ||
956 | formulation should be used for sure. | ||
957 | |||
958 | @item There should be two empty lines between the end of the function and | ||
959 | the comments describing the following function. There should be a single | ||
960 | empty line after the initial variable declarations of a function. If a | ||
961 | function has no local variables, there should be no initial empty line. If | ||
962 | a long function consists of several complex steps, those steps might be | ||
963 | separated by an empty line (possibly followed by a comment describing the | ||
964 | following step). The code should not contain empty lines in arbitrary | ||
965 | places; if in doubt, it is likely better to NOT have an empty line (this | ||
966 | way, more code will fit on the screen). | ||
967 | @end itemize | ||
968 | |||
969 | @c *********************************************************************** | ||
970 | @node Build-system | ||
971 | @section Build-system | ||
972 | |||
973 | If you have code that is likely not to compile or build rules you might | ||
974 | want to not trigger for most developers, use @code{if HAVE_EXPERIMENTAL} | ||
975 | in your @file{Makefile.am}. | ||
976 | Then it is OK to (temporarily) add non-compiling (or known-to-not-port) | ||
977 | code. | ||
978 | |||
979 | If you want to compile all testcases but NOT run them, run configure with | ||
980 | the @code{--enable-test-suppression} option. | ||
981 | |||
982 | If you want to run all testcases, including those that take a while, run | ||
983 | configure with the @code{--enable-expensive-testcases} option. | ||
984 | |||
985 | If you want to compile and run benchmarks, run configure with the | ||
986 | @code{--enable-benchmarks} option. | ||
987 | |||
988 | If you want to obtain code coverage results, run configure with the | ||
989 | @code{--enable-coverage} option and run the @file{coverage.sh} script in | ||
990 | the @file{contrib/} directory. | ||
991 | |||
992 | @cindex gnunet-ext | ||
993 | @node Developing extensions for GNUnet using the gnunet-ext template | ||
994 | @section Developing extensions for GNUnet using the gnunet-ext template | ||
995 | |||
996 | For developers who want to write extensions for GNUnet we provide the | ||
997 | gnunet-ext template to provide an easy to use skeleton. | ||
998 | |||
999 | gnunet-ext contains the build environment and template files for the | ||
1000 | development of GNUnet services, command line tools, APIs and tests. | ||
1001 | |||
1002 | First of all you have to obtain gnunet-ext from git: | ||
1003 | |||
1004 | @example | ||
1005 | git clone https://gnunet.org/git/gnunet-ext.git | ||
1006 | @end example | ||
1007 | |||
1008 | The next step is to bootstrap and configure it. For configure you have to | ||
1009 | provide the path containing GNUnet with | ||
1010 | @code{--with-gnunet=/path/to/gnunet} and the prefix where you want the | ||
1011 | install the extension using @code{--prefix=/path/to/install}: | ||
1012 | |||
1013 | @example | ||
1014 | ./bootstrap | ||
1015 | ./configure --prefix=/path/to/install --with-gnunet=/path/to/gnunet | ||
1016 | @end example | ||
1017 | |||
1018 | When your GNUnet installation is not included in the default linker search | ||
1019 | path, you have to add @code{/path/to/gnunet} to the file | ||
1020 | @file{/etc/ld.so.conf} and run @code{ldconfig} or your add it to the | ||
1021 | environmental variable @code{LD_LIBRARY_PATH} by using | ||
1022 | |||
1023 | @example | ||
1024 | export LD_LIBRARY_PATH=/path/to/gnunet/lib | ||
1025 | @end example | ||
1026 | |||
1027 | @cindex writing testcases | ||
1028 | @node Writing testcases | ||
1029 | @section Writing testcases | ||
1030 | |||
1031 | Ideally, any non-trivial GNUnet code should be covered by automated | ||
1032 | testcases. Testcases should reside in the same place as the code that is | ||
1033 | being tested. The name of source files implementing tests should begin | ||
1034 | with @code{test_} followed by the name of the file that contains | ||
1035 | the code that is being tested. | ||
1036 | |||
1037 | Testcases in GNUnet should be integrated with the autotools build system. | ||
1038 | This way, developers and anyone building binary packages will be able to | ||
1039 | run all testcases simply by running @code{make check}. The final | ||
1040 | testcases shipped with the distribution should output at most some brief | ||
1041 | progress information and not display debug messages by default. The | ||
1042 | success or failure of a testcase must be indicated by returning zero | ||
1043 | (success) or non-zero (failure) from the main method of the testcase. | ||
1044 | The integration with the autotools is relatively straightforward and only | ||
1045 | requires modifications to the @file{Makefile.am} in the directory | ||
1046 | containing the testcase. For a testcase testing the code in @file{foo.c} | ||
1047 | the @file{Makefile.am} would contain the following lines: | ||
1048 | |||
1049 | @example | ||
1050 | check_PROGRAMS = test_foo | ||
1051 | TESTS = $(check_PROGRAMS) | ||
1052 | test_foo_SOURCES = test_foo.c | ||
1053 | test_foo_LDADD = $(top_builddir)/src/util/libgnunetutil.la | ||
1054 | @end example | ||
1055 | |||
1056 | Naturally, other libraries used by the testcase may be specified in the | ||
1057 | @code{LDADD} directive as necessary. | ||
1058 | |||
1059 | Often testcases depend on additional input files, such as a configuration | ||
1060 | file. These support files have to be listed using the @code{EXTRA_DIST} | ||
1061 | directive in order to ensure that they are included in the distribution. | ||
1062 | |||
1063 | Example: | ||
1064 | |||
1065 | @example | ||
1066 | EXTRA_DIST = test_foo_data.conf | ||
1067 | @end example | ||
1068 | |||
1069 | Executing @code{make check} will run all testcases in the current | ||
1070 | directory and all subdirectories. Testcases can be compiled individually | ||
1071 | by running @code{make test_foo} and then invoked directly using | ||
1072 | @code{./test_foo}. Note that due to the use of plugins in GNUnet, it is | ||
1073 | typically necessary to run @code{make install} before running any | ||
1074 | testcases. Thus the canonical command @code{make check install} has to be | ||
1075 | changed to @code{make install check} for GNUnet. | ||
1076 | |||
1077 | @cindex TESTING library | ||
1078 | @node TESTING library | ||
1079 | @section TESTING library | ||
1080 | |||
1081 | The TESTING library is used for writing testcases which involve starting a | ||
1082 | single or multiple peers. While peers can also be started by testcases | ||
1083 | using the ARM subsystem, using TESTING library provides an elegant way to | ||
1084 | do this. The configurations of the peers are auto-generated from a given | ||
1085 | template to have non-conflicting port numbers ensuring that peers' | ||
1086 | services do not run into bind errors. This is achieved by testing ports' | ||
1087 | availability by binding a listening socket to them before allocating them | ||
1088 | to services in the generated configurations. | ||
1089 | |||
1090 | An another advantage while using TESTING is that it shortens the testcase | ||
1091 | startup time as the hostkeys for peers are copied from a pre-computed set | ||
1092 | of hostkeys instead of generating them at peer startup which may take a | ||
1093 | considerable amount of time when starting multiple peers or on an embedded | ||
1094 | processor. | ||
1095 | |||
1096 | TESTING also allows for certain services to be shared among peers. This | ||
1097 | feature is invaluable when testing with multiple peers as it helps to | ||
1098 | reduce the number of services run per each peer and hence the total | ||
1099 | number of processes run per testcase. | ||
1100 | |||
1101 | TESTING library only handles creating, starting and stopping peers. | ||
1102 | Features useful for testcases such as connecting peers in a topology are | ||
1103 | not available in TESTING but are available in the TESTBED subsystem. | ||
1104 | Furthermore, TESTING only creates peers on the localhost, however by | ||
1105 | using TESTBED testcases can benefit from creating peers across multiple | ||
1106 | hosts. | ||
1107 | |||
1108 | @menu | ||
1109 | * API:: | ||
1110 | * Finer control over peer stop:: | ||
1111 | * Helper functions:: | ||
1112 | * Testing with multiple processes:: | ||
1113 | @end menu | ||
1114 | |||
1115 | @cindex TESTING API | ||
1116 | @node API | ||
1117 | @subsection API | ||
1118 | |||
1119 | TESTING abstracts a group of peers as a TESTING system. All peers in a | ||
1120 | system have common hostname and no two services of these peers have a | ||
1121 | same port or a UNIX domain socket path. | ||
1122 | |||
1123 | TESTING system can be created with the function | ||
1124 | @code{GNUNET_TESTING_system_create()} which returns a handle to the | ||
1125 | system. This function takes a directory path which is used for generating | ||
1126 | the configurations of peers, an IP address from which connections to the | ||
1127 | peers' services should be allowed, the hostname to be used in peers' | ||
1128 | configuration, and an array of shared service specifications of type | ||
1129 | @code{struct GNUNET_TESTING_SharedService}. | ||
1130 | |||
1131 | The shared service specification must specify the name of the service to | ||
1132 | share, the configuration pertaining to that shared service and the | ||
1133 | maximum number of peers that are allowed to share a single instance of | ||
1134 | the shared service. | ||
1135 | |||
1136 | TESTING system created with @code{GNUNET_TESTING_system_create()} chooses | ||
1137 | ports from the default range @code{12000} - @code{56000} while | ||
1138 | auto-generating configurations for peers. | ||
1139 | This range can be customised with the function | ||
1140 | @code{GNUNET_TESTING_system_create_with_portrange()}. This function is | ||
1141 | similar to @code{GNUNET_TESTING_system_create()} except that it take 2 | ||
1142 | additional parameters --- the start and end of the port range to use. | ||
1143 | |||
1144 | A TESTING system is destroyed with the funciton | ||
1145 | @code{GNUNET_TESTING_system_destory()}. This function takes the handle of | ||
1146 | the system and a flag to remove the files created in the directory used | ||
1147 | to generate configurations. | ||
1148 | |||
1149 | A peer is created with the function | ||
1150 | @code{GNUNET_TESTING_peer_configure()}. This functions takes the system | ||
1151 | handle, a configuration template from which the configuration for the peer | ||
1152 | is auto-generated and the index from where the hostkey for the peer has to | ||
1153 | be copied from. When successfull, this function returs a handle to the | ||
1154 | peer which can be used to start and stop it and to obtain the identity of | ||
1155 | the peer. If unsuccessful, a NULL pointer is returned with an error | ||
1156 | message. This function handles the generated configuration to have | ||
1157 | non-conflicting ports and paths. | ||
1158 | |||
1159 | Peers can be started and stopped by calling the functions | ||
1160 | @code{GNUNET_TESTING_peer_start()} and @code{GNUNET_TESTING_peer_stop()} | ||
1161 | respectively. A peer can be destroyed by calling the function | ||
1162 | @code{GNUNET_TESTING_peer_destroy}. When a peer is destroyed, the ports | ||
1163 | and paths in allocated in its configuration are reclaimed for usage in new | ||
1164 | peers. | ||
1165 | |||
1166 | @c *********************************************************************** | ||
1167 | @node Finer control over peer stop | ||
1168 | @subsection Finer control over peer stop | ||
1169 | |||
1170 | Using @code{GNUNET_TESTING_peer_stop()} is normally fine for testcases. | ||
1171 | However, calling this function for each peer is inefficient when trying to | ||
1172 | shutdown multiple peers as this function sends the termination signal to | ||
1173 | the given peer process and waits for it to terminate. It would be faster | ||
1174 | in this case to send the termination signals to the peers first and then | ||
1175 | wait on them. This is accomplished by the functions | ||
1176 | @code{GNUNET_TESTING_peer_kill()} which sends a termination signal to the | ||
1177 | peer, and the function @code{GNUNET_TESTING_peer_wait()} which waits on | ||
1178 | the peer. | ||
1179 | |||
1180 | Further finer control can be achieved by choosing to stop a peer | ||
1181 | asynchronously with the function @code{GNUNET_TESTING_peer_stop_async()}. | ||
1182 | This function takes a callback parameter and a closure for it in addition | ||
1183 | to the handle to the peer to stop. The callback function is called with | ||
1184 | the given closure when the peer is stopped. Using this function | ||
1185 | eliminates blocking while waiting for the peer to terminate. | ||
1186 | |||
1187 | An asynchronous peer stop can be cancelled by calling the function | ||
1188 | @code{GNUNET_TESTING_peer_stop_async_cancel()}. Note that calling this | ||
1189 | function does not prevent the peer from terminating if the termination | ||
1190 | signal has already been sent to it. It does, however, cancels the | ||
1191 | callback to be called when the peer is stopped. | ||
1192 | |||
1193 | @c *********************************************************************** | ||
1194 | @node Helper functions | ||
1195 | @subsection Helper functions | ||
1196 | |||
1197 | Most of the testcases can benefit from an abstraction which configures a | ||
1198 | peer and starts it. This is provided by the function | ||
1199 | @code{GNUNET_TESTING_peer_run()}. This function takes the testing | ||
1200 | directory pathname, a configuration template, a callback and its closure. | ||
1201 | This function creates a peer in the given testing directory by using the | ||
1202 | configuration template, starts the peer and calls the given callback with | ||
1203 | the given closure. | ||
1204 | |||
1205 | The function @code{GNUNET_TESTING_peer_run()} starts the ARM service of | ||
1206 | the peer which starts the rest of the configured services. A similar | ||
1207 | function @code{GNUNET_TESTING_service_run} can be used to just start a | ||
1208 | single service of a peer. In this case, the peer's ARM service is not | ||
1209 | started; instead, only the given service is run. | ||
1210 | |||
1211 | @c *********************************************************************** | ||
1212 | @node Testing with multiple processes | ||
1213 | @subsection Testing with multiple processes | ||
1214 | |||
1215 | When testing GNUnet, the splitting of the code into a services and clients | ||
1216 | often complicates testing. The solution to this is to have the testcase | ||
1217 | fork @code{gnunet-service-arm}, ask it to start the required server and | ||
1218 | daemon processes and then execute appropriate client actions (to test the | ||
1219 | client APIs or the core module or both). If necessary, multiple ARM | ||
1220 | services can be forked using different ports (!) to simulate a network. | ||
1221 | However, most of the time only one ARM process is needed. Note that on | ||
1222 | exit, the testcase should shutdown ARM with a @code{TERM} signal (to give | ||
1223 | it the chance to cleanly stop its child processes). | ||
1224 | |||
1225 | The following code illustrates spawning and killing an ARM process from a | ||
1226 | testcase: | ||
1227 | |||
1228 | @example | ||
1229 | static void run (void *cls, | ||
1230 | char *const *args, | ||
1231 | const char *cfgfile, | ||
1232 | const struct GNUNET_CONFIGURATION_Handle *cfg) @{ | ||
1233 | struct GNUNET_OS_Process *arm_pid; | ||
1234 | arm_pid = GNUNET_OS_start_process (NULL, | ||
1235 | NULL, | ||
1236 | "gnunet-service-arm", | ||
1237 | "gnunet-service-arm", | ||
1238 | "-c", | ||
1239 | cfgname, | ||
1240 | NULL); | ||
1241 | /* do real test work here */ | ||
1242 | if (0 != GNUNET_OS_process_kill (arm_pid, SIGTERM)) | ||
1243 | GNUNET_log_strerror | ||
1244 | (GNUNET_ERROR_TYPE_WARNING, "kill"); | ||
1245 | GNUNET_assert (GNUNET_OK == GNUNET_OS_process_wait (arm_pid)); | ||
1246 | GNUNET_OS_process_close (arm_pid); @} | ||
1247 | |||
1248 | GNUNET_PROGRAM_run (argc, argv, | ||
1249 | "NAME-OF-TEST", | ||
1250 | "nohelp", | ||
1251 | options, | ||
1252 | &run, | ||
1253 | cls); | ||
1254 | @end example | ||
1255 | |||
1256 | |||
1257 | An alternative way that works well to test plugins is to implement a | ||
1258 | mock-version of the environment that the plugin expects and then to | ||
1259 | simply load the plugin directly. | ||
1260 | |||
1261 | @c *********************************************************************** | ||
1262 | @node Performance regression analysis with Gauger | ||
1263 | @section Performance regression analysis with Gauger | ||
1264 | |||
1265 | To help avoid performance regressions, GNUnet uses Gauger. Gauger is a | ||
1266 | simple logging tool that allows remote hosts to send performance data to | ||
1267 | a central server, where this data can be analyzed and visualized. Gauger | ||
1268 | shows graphs of the repository revisions and the performace data recorded | ||
1269 | for each revision, so sudden performance peaks or drops can be identified | ||
1270 | and linked to a specific revision number. | ||
1271 | |||
1272 | In the case of GNUnet, the buildbots log the performance data obtained | ||
1273 | during the tests after each build. The data can be accesed on GNUnet's | ||
1274 | Gauger page. | ||
1275 | |||
1276 | The menu on the left allows to select either the results of just one | ||
1277 | build bot (under "Hosts") or review the data from all hosts for a given | ||
1278 | test result (under "Metrics"). In case of very different absolute value | ||
1279 | of the results, for instance arm vs. amd64 machines, the option | ||
1280 | "Normalize" on a metric view can help to get an idea about the | ||
1281 | performance evolution across all hosts. | ||
1282 | |||
1283 | Using Gauger in GNUnet and having the performance of a module tracked over | ||
1284 | time is very easy. First of course, the testcase must generate some | ||
1285 | consistent metric, which makes sense to have logged. Highly volatile or | ||
1286 | random dependant metrics probably are not ideal candidates for meaningful | ||
1287 | regression detection. | ||
1288 | |||
1289 | To start logging any value, just include @code{gauger.h} in your testcase | ||
1290 | code. Then, use the macro @code{GAUGER()} to make the Buildbots log | ||
1291 | whatever value is of interest for you to @code{gnunet.org}'s Gauger | ||
1292 | server. No setup is necessary as most Buildbots have already everything | ||
1293 | in place and new metrics are created on demand. To delete a metric, you | ||
1294 | need to contact a member of the GNUnet development team (a file will need | ||
1295 | to be removed manually from the respective directory). | ||
1296 | |||
1297 | The code in the test should look like this: | ||
1298 | |||
1299 | @example | ||
1300 | [other includes] | ||
1301 | #include <gauger.h> | ||
1302 | |||
1303 | int main (int argc, char *argv[]) @{ | ||
1304 | |||
1305 | [run test, generate data] | ||
1306 | GAUGER("YOUR_MODULE", | ||
1307 | "METRIC_NAME", | ||
1308 | (float)value, | ||
1309 | "UNIT"); @} | ||
1310 | @end example | ||
1311 | |||
1312 | Where: | ||
1313 | |||
1314 | @table @asis | ||
1315 | |||
1316 | @item @strong{YOUR_MODULE} is a category in the gauger page and should be | ||
1317 | the name of the module or subsystem like "Core" or "DHT" | ||
1318 | @item @strong{METRIC} is | ||
1319 | the name of the metric being collected and should be concise and | ||
1320 | descriptive, like "PUT operations in sqlite-datastore". | ||
1321 | @item @strong{value} is the value | ||
1322 | of the metric that is logged for this run. | ||
1323 | @item @strong{UNIT} is the unit in | ||
1324 | which the value is measured, for instance "kb/s" or "kb of RAM/node". | ||
1325 | @end table | ||
1326 | |||
1327 | If you wish to use Gauger for your own project, you can grab a copy of the | ||
1328 | latest stable release or check out Gauger's Subversion repository. | ||
1329 | |||
1330 | @cindex TESTBED Subsystem | ||
1331 | @node TESTBED Subsystem | ||
1332 | @section TESTBED Subsystem | ||
1333 | |||
1334 | The TESTBED subsystem facilitates testing and measuring of multi-peer | ||
1335 | deployments on a single host or over multiple hosts. | ||
1336 | |||
1337 | The architecture of the testbed module is divided into the following: | ||
1338 | @itemize @bullet | ||
1339 | |||
1340 | @item Testbed API: An API which is used by the testing driver programs. It | ||
1341 | provides with functions for creating, destroying, starting, stopping | ||
1342 | peers, etc. | ||
1343 | |||
1344 | @item Testbed service (controller): A service which is started through the | ||
1345 | Testbed API. This service handles operations to create, destroy, start, | ||
1346 | stop peers, connect them, modify their configurations. | ||
1347 | |||
1348 | @item Testbed helper: When a controller has to be started on a host, the | ||
1349 | testbed API starts the testbed helper on that host which in turn starts | ||
1350 | the controller. The testbed helper receives a configuration for the | ||
1351 | controller through its stdin and changes it to ensure the controller | ||
1352 | doesn't run into any port conflict on that host. | ||
1353 | @end itemize | ||
1354 | |||
1355 | |||
1356 | The testbed service (controller) is different from the other GNUnet | ||
1357 | services in that it is not started by ARM and is not supposed to be run | ||
1358 | as a daemon. It is started by the testbed API through a testbed helper. | ||
1359 | In a typical scenario involving multiple hosts, a controller is started | ||
1360 | on each host. Controllers take up the actual task of creating peers, | ||
1361 | starting and stopping them on the hosts they run. | ||
1362 | |||
1363 | While running deployments on a single localhost the testbed API starts the | ||
1364 | testbed helper directly as a child process. When running deployments on | ||
1365 | remote hosts the testbed API starts Testbed Helpers on each remote host | ||
1366 | through remote shell. By default testbed API uses SSH as a remote shell. | ||
1367 | This can be changed by setting the environmental variable | ||
1368 | GNUNET_TESTBED_RSH_CMD to the required remote shell program. This | ||
1369 | variable can also contain parameters which are to be passed to the remote | ||
1370 | shell program. For e.g: | ||
1371 | |||
1372 | @example | ||
1373 | export GNUNET_TESTBED_RSH_CMD="ssh -o BatchMode=yes \ | ||
1374 | -o NoHostAuthenticationForLocalhost=yes %h" | ||
1375 | @end example | ||
1376 | |||
1377 | Substitutions are allowed in the command string above, | ||
1378 | this allows for substitutions through placemarks which begin with a `%'. | ||
1379 | At present the following substitutions are supported | ||
1380 | |||
1381 | @itemize @bullet | ||
1382 | @item %h: hostname | ||
1383 | @item %u: username | ||
1384 | @item %p: port | ||
1385 | @end itemize | ||
1386 | |||
1387 | Note that the substitution placemark is replaced only when the | ||
1388 | corresponding field is available and only once. Specifying | ||
1389 | |||
1390 | @example | ||
1391 | %u@atchar{}%h | ||
1392 | @end example | ||
1393 | |||
1394 | doesn't work either. If you want to user username substitutions for | ||
1395 | @command{SSH}, use the argument @code{-l} before the | ||
1396 | username substitution. | ||
1397 | |||
1398 | For example: | ||
1399 | @example | ||
1400 | ssh -l %u -p %p %h | ||
1401 | @end example | ||
1402 | |||
1403 | The testbed API and the helper communicate through the helpers stdin and | ||
1404 | stdout. As the helper is started through a remote shell on remote hosts | ||
1405 | any output messages from the remote shell interfere with the communication | ||
1406 | and results in a failure while starting the helper. For this reason, it is | ||
1407 | suggested to use flags to make the remote shells produce no output | ||
1408 | messages and to have password-less logins. The default remote shell, SSH, | ||
1409 | the default options are: | ||
1410 | |||
1411 | @example | ||
1412 | -o BatchMode=yes -o NoHostBasedAuthenticationForLocalhost=yes" | ||
1413 | @end example | ||
1414 | |||
1415 | Password-less logins should be ensured by using SSH keys. | ||
1416 | |||
1417 | Since the testbed API executes the remote shell as a non-interactive | ||
1418 | shell, certain scripts like .bashrc, .profiler may not be executed. If | ||
1419 | this is the case testbed API can be forced to execute an interactive | ||
1420 | shell by setting up the environmental variable | ||
1421 | @code{GNUNET_TESTBED_RSH_CMD_SUFFIX} to a shell program. | ||
1422 | |||
1423 | An example could be: | ||
1424 | |||
1425 | @example | ||
1426 | export GNUNET_TESTBED_RSH_CMD_SUFFIX="sh -lc" | ||
1427 | @end example | ||
1428 | |||
1429 | The testbed API will then execute the remote shell program as: | ||
1430 | |||
1431 | @example | ||
1432 | $GNUNET_TESTBED_RSH_CMD -p $port $dest $GNUNET_TESTBED_RSH_CMD_SUFFIX \ | ||
1433 | gnunet-helper-testbed | ||
1434 | @end example | ||
1435 | |||
1436 | On some systems, problems may arise while starting testbed helpers if | ||
1437 | GNUnet is installed into a custom location since the helper may not be | ||
1438 | found in the standard path. This can be addressed by setting the variable | ||
1439 | `@code{HELPER_BINARY_PATH}' to the path of the testbed helper. | ||
1440 | Testbed API will then use this path to start helper binaries both | ||
1441 | locally and remotely. | ||
1442 | |||
1443 | Testbed API can accessed by including the | ||
1444 | @file{gnunet_testbed_service.h} file and linking with | ||
1445 | @code{-lgnunettestbed}. | ||
1446 | |||
1447 | @c *********************************************************************** | ||
1448 | @menu | ||
1449 | * Supported Topologies:: | ||
1450 | * Hosts file format:: | ||
1451 | * Topology file format:: | ||
1452 | * Testbed Barriers:: | ||
1453 | * Automatic large-scale deployment in the PlanetLab testbed:: | ||
1454 | * TESTBED Caveats:: | ||
1455 | @end menu | ||
1456 | |||
1457 | @node Supported Topologies | ||
1458 | @subsection Supported Topologies | ||
1459 | |||
1460 | While testing multi-peer deployments, it is often needed that the peers | ||
1461 | are connected in some topology. This requirement is addressed by the | ||
1462 | function @code{GNUNET_TESTBED_overlay_connect()} which connects any given | ||
1463 | two peers in the testbed. | ||
1464 | |||
1465 | The API also provides a helper function | ||
1466 | @code{GNUNET_TESTBED_overlay_configure_topology()} to connect a given set | ||
1467 | of peers in any of the following supported topologies: | ||
1468 | |||
1469 | @itemize @bullet | ||
1470 | |||
1471 | @item @code{GNUNET_TESTBED_TOPOLOGY_CLIQUE}: All peers are connected with | ||
1472 | each other | ||
1473 | |||
1474 | @item @code{GNUNET_TESTBED_TOPOLOGY_LINE}: Peers are connected to form a | ||
1475 | line | ||
1476 | |||
1477 | @item @code{GNUNET_TESTBED_TOPOLOGY_RING}: Peers are connected to form a | ||
1478 | ring topology | ||
1479 | |||
1480 | @item @code{GNUNET_TESTBED_TOPOLOGY_2D_TORUS}: Peers are connected to | ||
1481 | form a 2 dimensional torus topology. The number of peers may not be a | ||
1482 | perfect square, in that case the resulting torus may not have the uniform | ||
1483 | poloidal and toroidal lengths | ||
1484 | |||
1485 | @item @code{GNUNET_TESTBED_TOPOLOGY_ERDOS_RENYI}: Topology is generated | ||
1486 | to form a random graph. The number of links to be present should be given | ||
1487 | |||
1488 | @item @code{GNUNET_TESTBED_TOPOLOGY_SMALL_WORLD}: Peers are connected to | ||
1489 | form a 2D Torus with some random links among them. The number of random | ||
1490 | links are to be given | ||
1491 | |||
1492 | @item @code{GNUNET_TESTBED_TOPOLOGY_SMALL_WORLD_RING}: Peers are | ||
1493 | connected to form a ring with some random links among them. The number of | ||
1494 | random links are to be given | ||
1495 | |||
1496 | @item @code{GNUNET_TESTBED_TOPOLOGY_SCALE_FREE}: Connects peers in a | ||
1497 | topology where peer connectivity follows power law - new peers are | ||
1498 | connected with high probabililty to well connected peers. | ||
1499 | @footnote{See Emergence of Scaling in Random Networks. Science 286, | ||
1500 | 509-512, 1999 | ||
1501 | (@uref{https://gnunet.org/git/bibliography.git/plain/docs/emergence_of_scaling_in_random_networks__barabasi_albert_science_286__1999.pdf, pdf})} | ||
1502 | |||
1503 | @item @code{GNUNET_TESTBED_TOPOLOGY_FROM_FILE}: The topology information | ||
1504 | is loaded from a file. The path to the file has to be given. | ||
1505 | @xref{Topology file format}, for the format of this file. | ||
1506 | |||
1507 | @item @code{GNUNET_TESTBED_TOPOLOGY_NONE}: No topology | ||
1508 | @end itemize | ||
1509 | |||
1510 | |||
1511 | The above supported topologies can be specified respectively by setting | ||
1512 | the variable @code{OVERLAY_TOPOLOGY} to the following values in the | ||
1513 | configuration passed to Testbed API functions | ||
1514 | @code{GNUNET_TESTBED_test_run()} and | ||
1515 | @code{GNUNET_TESTBED_run()}: | ||
1516 | |||
1517 | @itemize @bullet | ||
1518 | @item @code{CLIQUE} | ||
1519 | @item @code{RING} | ||
1520 | @item @code{LINE} | ||
1521 | @item @code{2D_TORUS} | ||
1522 | @item @code{RANDOM} | ||
1523 | @item @code{SMALL_WORLD} | ||
1524 | @item @code{SMALL_WORLD_RING} | ||
1525 | @item @code{SCALE_FREE} | ||
1526 | @item @code{FROM_FILE} | ||
1527 | @item @code{NONE} | ||
1528 | @end itemize | ||
1529 | |||
1530 | |||
1531 | Topologies @code{RANDOM}, @code{SMALL_WORLD} and @code{SMALL_WORLD_RING} | ||
1532 | require the option @code{OVERLAY_RANDOM_LINKS} to be set to the number of | ||
1533 | random links to be generated in the configuration. The option will be | ||
1534 | ignored for the rest of the topologies. | ||
1535 | |||
1536 | Topology @code{SCALE_FREE} requires the options | ||
1537 | @code{SCALE_FREE_TOPOLOGY_CAP} to be set to the maximum number of peers | ||
1538 | which can connect to a peer and @code{SCALE_FREE_TOPOLOGY_M} to be set to | ||
1539 | how many peers a peer should be atleast connected to. | ||
1540 | |||
1541 | Similarly, the topology @code{FROM_FILE} requires the option | ||
1542 | @code{OVERLAY_TOPOLOGY_FILE} to contain the path of the file containing | ||
1543 | the topology information. This option is ignored for the rest of the | ||
1544 | topologies. @xref{Topology file format}, for the format of this file. | ||
1545 | |||
1546 | @c *********************************************************************** | ||
1547 | @node Hosts file format | ||
1548 | @subsection Hosts file format | ||
1549 | |||
1550 | The testbed API offers the function | ||
1551 | @code{GNUNET_TESTBED_hosts_load_from_file()} to load from a given file | ||
1552 | details about the hosts which testbed can use for deploying peers. | ||
1553 | This function is useful to keep the data about hosts | ||
1554 | separate instead of hard coding them in code. | ||
1555 | |||
1556 | Another helper function from testbed API, @code{GNUNET_TESTBED_run()} | ||
1557 | also takes a hosts file name as its parameter. It uses the above | ||
1558 | function to populate the hosts data structures and start controllers to | ||
1559 | deploy peers. | ||
1560 | |||
1561 | These functions require the hosts file to be of the following format: | ||
1562 | @itemize @bullet | ||
1563 | @item Each line is interpreted to have details about a host | ||
1564 | @item Host details should include the username to use for logging into the | ||
1565 | host, the hostname of the host and the port number to use for the remote | ||
1566 | shell program. All thee values should be given. | ||
1567 | @item These details should be given in the following format: | ||
1568 | @example | ||
1569 | <username>@@<hostname>:<port> | ||
1570 | @end example | ||
1571 | @end itemize | ||
1572 | |||
1573 | Note that having canonical hostnames may cause problems while resolving | ||
1574 | the IP addresses (See this bug). Hence it is advised to provide the hosts' | ||
1575 | IP numerical addresses as hostnames whenever possible. | ||
1576 | |||
1577 | @c *********************************************************************** | ||
1578 | @node Topology file format | ||
1579 | @subsection Topology file format | ||
1580 | |||
1581 | A topology file describes how peers are to be connected. It should adhere | ||
1582 | to the following format for testbed to parse it correctly. | ||
1583 | |||
1584 | Each line should begin with the target peer id. This should be followed by | ||
1585 | a colon(`:') and origin peer ids seperated by `|'. All spaces except for | ||
1586 | newline characters are ignored. The API will then try to connect each | ||
1587 | origin peer to the target peer. | ||
1588 | |||
1589 | For example, the following file will result in 5 overlay connections: | ||
1590 | [2->1], [3->1],[4->3], [0->3], [2->0]@ | ||
1591 | @code{@ 1:2|3@ 3:4| 0@ 0: 2@ } | ||
1592 | |||
1593 | @c *********************************************************************** | ||
1594 | @node Testbed Barriers | ||
1595 | @subsection Testbed Barriers | ||
1596 | |||
1597 | The testbed subsystem's barriers API facilitates coordination among the | ||
1598 | peers run by the testbed and the experiment driver. The concept is | ||
1599 | similar to the barrier synchronisation mechanism found in parallel | ||
1600 | programming or multi-threading paradigms - a peer waits at a barrier upon | ||
1601 | reaching it until the barrier is reached by a predefined number of peers. | ||
1602 | This predefined number of peers required to cross a barrier is also called | ||
1603 | quorum. We say a peer has reached a barrier if the peer is waiting for the | ||
1604 | barrier to be crossed. Similarly a barrier is said to be reached if the | ||
1605 | required quorum of peers reach the barrier. A barrier which is reached is | ||
1606 | deemed as crossed after all the peers waiting on it are notified. | ||
1607 | |||
1608 | The barriers API provides the following functions: | ||
1609 | @itemize @bullet | ||
1610 | @item @strong{@code{GNUNET_TESTBED_barrier_init()}:} function to | ||
1611 | initialse a barrier in the experiment | ||
1612 | @item @strong{@code{GNUNET_TESTBED_barrier_cancel()}:} function to cancel | ||
1613 | a barrier which has been initialised before | ||
1614 | @item @strong{@code{GNUNET_TESTBED_barrier_wait()}:} function to signal | ||
1615 | barrier service that the caller has reached a barrier and is waiting for | ||
1616 | it to be crossed | ||
1617 | @item @strong{@code{GNUNET_TESTBED_barrier_wait_cancel()}:} function to | ||
1618 | stop waiting for a barrier to be crossed | ||
1619 | @end itemize | ||
1620 | |||
1621 | |||
1622 | Among the above functions, the first two, namely | ||
1623 | @code{GNUNET_TESTBED_barrier_init()} and | ||
1624 | @code{GNUNET_TESTBED_barrier_cancel()} are used by experiment drivers. All | ||
1625 | barriers should be initialised by the experiment driver by calling | ||
1626 | @code{GNUNET_TESTBED_barrier_init()}. This function takes a name to | ||
1627 | identify the barrier, the quorum required for the barrier to be crossed | ||
1628 | and a notification callback for notifying the experiment driver when the | ||
1629 | barrier is crossed. @code{GNUNET_TESTBED_barrier_cancel()} cancels an | ||
1630 | initialised barrier and frees the resources allocated for it. This | ||
1631 | function can be called upon a initialised barrier before it is crossed. | ||
1632 | |||
1633 | The remaining two functions @code{GNUNET_TESTBED_barrier_wait()} and | ||
1634 | @code{GNUNET_TESTBED_barrier_wait_cancel()} are used in the peer's | ||
1635 | processes. @code{GNUNET_TESTBED_barrier_wait()} connects to the local | ||
1636 | barrier service running on the same host the peer is running on and | ||
1637 | registers that the caller has reached the barrier and is waiting for the | ||
1638 | barrier to be crossed. Note that this function can only be used by peers | ||
1639 | which are started by testbed as this function tries to access the local | ||
1640 | barrier service which is part of the testbed controller service. Calling | ||
1641 | @code{GNUNET_TESTBED_barrier_wait()} on an uninitialised barrier results | ||
1642 | in failure. @code{GNUNET_TESTBED_barrier_wait_cancel()} cancels the | ||
1643 | notification registered by @code{GNUNET_TESTBED_barrier_wait()}. | ||
1644 | |||
1645 | |||
1646 | @c *********************************************************************** | ||
1647 | @menu | ||
1648 | * Implementation:: | ||
1649 | @end menu | ||
1650 | |||
1651 | @node Implementation | ||
1652 | @subsubsection Implementation | ||
1653 | |||
1654 | Since barriers involve coordination between experiment driver and peers, | ||
1655 | the barrier service in the testbed controller is split into two | ||
1656 | components. The first component responds to the message generated by the | ||
1657 | barrier API used by the experiment driver (functions | ||
1658 | @code{GNUNET_TESTBED_barrier_init()} and | ||
1659 | @code{GNUNET_TESTBED_barrier_cancel()}) and the second component to the | ||
1660 | messages generated by barrier API used by peers (functions | ||
1661 | @code{GNUNET_TESTBED_barrier_wait()} and | ||
1662 | @code{GNUNET_TESTBED_barrier_wait_cancel()}). | ||
1663 | |||
1664 | Calling @code{GNUNET_TESTBED_barrier_init()} sends a | ||
1665 | @code{GNUNET_MESSAGE_TYPE_TESTBED_BARRIER_INIT} message to the master | ||
1666 | controller. The master controller then registers a barrier and calls | ||
1667 | @code{GNUNET_TESTBED_barrier_init()} for each its subcontrollers. In this | ||
1668 | way barrier initialisation is propagated to the controller hierarchy. | ||
1669 | While propagating initialisation, any errors at a subcontroller such as | ||
1670 | timeout during further propagation are reported up the hierarchy back to | ||
1671 | the experiment driver. | ||
1672 | |||
1673 | Similar to @code{GNUNET_TESTBED_barrier_init()}, | ||
1674 | @code{GNUNET_TESTBED_barrier_cancel()} propagates | ||
1675 | @code{GNUNET_MESSAGE_TYPE_TESTBED_BARRIER_CANCEL} message which causes | ||
1676 | controllers to remove an initialised barrier. | ||
1677 | |||
1678 | The second component is implemented as a separate service in the binary | ||
1679 | `gnunet-service-testbed' which already has the testbed controller service. | ||
1680 | Although this deviates from the gnunet process architecture of having one | ||
1681 | service per binary, it is needed in this case as this component needs | ||
1682 | access to barrier data created by the first component. This component | ||
1683 | responds to @code{GNUNET_MESSAGE_TYPE_TESTBED_BARRIER_WAIT} messages from | ||
1684 | local peers when they call @code{GNUNET_TESTBED_barrier_wait()}. Upon | ||
1685 | receiving @code{GNUNET_MESSAGE_TYPE_TESTBED_BARRIER_WAIT} message, the | ||
1686 | service checks if the requested barrier has been initialised before and | ||
1687 | if it was not initialised, an error status is sent through | ||
1688 | @code{GNUNET_MESSAGE_TYPE_TESTBED_BARRIER_STATUS} message to the local | ||
1689 | peer and the connection from the peer is terminated. If the barrier is | ||
1690 | initialised before, the barrier's counter for reached peers is incremented | ||
1691 | and a notification is registered to notify the peer when the barrier is | ||
1692 | reached. The connection from the peer is left open. | ||
1693 | |||
1694 | When enough peers required to attain the quorum send | ||
1695 | @code{GNUNET_MESSAGE_TYPE_TESTBED_BARRIER_WAIT} messages, the controller | ||
1696 | sends a @code{GNUNET_MESSAGE_TYPE_TESTBED_BARRIER_STATUS} message to its | ||
1697 | parent informing that the barrier is crossed. If the controller has | ||
1698 | started further subcontrollers, it delays this message until it receives | ||
1699 | a similar notification from each of those subcontrollers. Finally, the | ||
1700 | barriers API at the experiment driver receives the | ||
1701 | @code{GNUNET_MESSAGE_TYPE_TESTBED_BARRIER_STATUS} when the barrier is | ||
1702 | reached at all the controllers. | ||
1703 | |||
1704 | The barriers API at the experiment driver responds to the | ||
1705 | @code{GNUNET_MESSAGE_TYPE_TESTBED_BARRIER_STATUS} message by echoing it | ||
1706 | back to the master controller and notifying the experiment controller | ||
1707 | through the notification callback that a barrier has been crossed. The | ||
1708 | echoed @code{GNUNET_MESSAGE_TYPE_TESTBED_BARRIER_STATUS} message is | ||
1709 | propagated by the master controller to the controller hierarchy. This | ||
1710 | propagation triggers the notifications registered by peers at each of the | ||
1711 | controllers in the hierarchy. Note the difference between this downward | ||
1712 | propagation of the @code{GNUNET_MESSAGE_TYPE_TESTBED_BARRIER_STATUS} | ||
1713 | message from its upward propagation --- the upward propagation is needed | ||
1714 | for ensuring that the barrier is reached by all the controllers and the | ||
1715 | downward propagation is for triggering that the barrier is crossed. | ||
1716 | |||
1717 | @cindex PlanetLab testbed | ||
1718 | @node Automatic large-scale deployment in the PlanetLab testbed | ||
1719 | @subsection Automatic large-scale deployment in the PlanetLab testbed | ||
1720 | |||
1721 | PlanetLab is a testbed for computer networking and distributed systems | ||
1722 | research. It was established in 2002 and as of June 2010 was composed of | ||
1723 | 1090 nodes at 507 sites worldwide. | ||
1724 | |||
1725 | To automate the GNUnet we created a set of automation tools to simplify | ||
1726 | the large-scale deployment. We provide you a set of scripts you can use | ||
1727 | to deploy GNUnet on a set of nodes and manage your installation. | ||
1728 | |||
1729 | Please also check @uref{https://gnunet.org/installation-fedora8-svn} and | ||
1730 | @uref{https://gnunet.org/installation-fedora12-svn} to find detailled | ||
1731 | instructions how to install GNUnet on a PlanetLab node. | ||
1732 | |||
1733 | |||
1734 | @c *********************************************************************** | ||
1735 | @menu | ||
1736 | * PlanetLab Automation for Fedora8 nodes:: | ||
1737 | * Install buildslave on PlanetLab nodes running fedora core 8:: | ||
1738 | * Setup a new PlanetLab testbed using GPLMT:: | ||
1739 | * Why do i get an ssh error when using the regex profiler?:: | ||
1740 | @end menu | ||
1741 | |||
1742 | @node PlanetLab Automation for Fedora8 nodes | ||
1743 | @subsubsection PlanetLab Automation for Fedora8 nodes | ||
1744 | |||
1745 | @c *********************************************************************** | ||
1746 | @node Install buildslave on PlanetLab nodes running fedora core 8 | ||
1747 | @subsubsection Install buildslave on PlanetLab nodes running fedora core 8 | ||
1748 | @c ** Actually this is a subsubsubsection, but must be fixed differently | ||
1749 | @c ** as subsubsection is the lowest. | ||
1750 | |||
1751 | Since most of the PlanetLab nodes are running the very old Fedora core 8 | ||
1752 | image, installing the buildslave software is quite some pain. For our | ||
1753 | PlanetLab testbed we figured out how to install the buildslave software | ||
1754 | best. | ||
1755 | |||
1756 | @c This is a vvery terrible way to suggest installing software. | ||
1757 | @c FIXME: Is there an official, safer way instead of blind-piping a | ||
1758 | @c script? | ||
1759 | @c FIXME: Use newer pypi URLs below. | ||
1760 | Install Distribute for Python: | ||
1761 | |||
1762 | @example | ||
1763 | curl http://python-distribute.org/distribute_setup.py | sudo python | ||
1764 | @end example | ||
1765 | |||
1766 | Install Distribute for zope.interface <= 3.8.0 (4.0 and 4.0.1 will not | ||
1767 | work): | ||
1768 | |||
1769 | @example | ||
1770 | export PYPI=@value{PYPI-URL} | ||
1771 | wget $PYPI/z/zope.interface/zope.interface-3.8.0.tar.gz | ||
1772 | tar zvfz zope.interface-3.8.0.tar.gz | ||
1773 | cd zope.interface-3.8.0 | ||
1774 | sudo python setup.py install | ||
1775 | @end example | ||
1776 | |||
1777 | Install the buildslave software (0.8.6 was the latest version): | ||
1778 | |||
1779 | @example | ||
1780 | export GCODE="http://buildbot.googlecode.com/files" | ||
1781 | wget $GCODE/buildbot-slave-0.8.6p1.tar.gz | ||
1782 | tar xvfz buildbot-slave-0.8.6p1.tar.gz | ||
1783 | cd buildslave-0.8.6p1 | ||
1784 | sudo python setup.py install | ||
1785 | @end example | ||
1786 | |||
1787 | The setup will download the matching twisted package and install it. | ||
1788 | It will also try to install the latest version of zope.interface which | ||
1789 | will fail to install. Buildslave will work anyway since version 3.8.0 | ||
1790 | was installed before! | ||
1791 | |||
1792 | @c *********************************************************************** | ||
1793 | @node Setup a new PlanetLab testbed using GPLMT | ||
1794 | @subsubsection Setup a new PlanetLab testbed using GPLMT | ||
1795 | |||
1796 | @itemize @bullet | ||
1797 | @item Get a new slice and assign nodes | ||
1798 | Ask your PlanetLab PI to give you a new slice and assign the nodes you | ||
1799 | need | ||
1800 | @item Install a buildmaster | ||
1801 | You can stick to the buildbot documentation:@ | ||
1802 | @uref{http://buildbot.net/buildbot/docs/current/manual/installation.html} | ||
1803 | @item Install the buildslave software on all nodes | ||
1804 | To install the buildslave on all nodes assigned to your slice you can use | ||
1805 | the tasklist @code{install_buildslave_fc8.xml} provided with GPLMT: | ||
1806 | |||
1807 | @example | ||
1808 | ./gplmt.py -c contrib/tumple_gnunet.conf -t \ | ||
1809 | contrib/tasklists/install_buildslave_fc8.xml -a -p <planetlab password> | ||
1810 | @end example | ||
1811 | |||
1812 | @item Create the buildmaster configuration and the slave setup commands | ||
1813 | |||
1814 | The master and the and the slaves have need to have credentials and the | ||
1815 | master has to have all nodes configured. This can be done with the | ||
1816 | @file{create_buildbot_configuration.py} script in the @file{scripts} | ||
1817 | directory. | ||
1818 | |||
1819 | This scripts takes a list of nodes retrieved directly from PlanetLab or | ||
1820 | read from a file and a configuration template and creates: | ||
1821 | |||
1822 | @itemize @bullet | ||
1823 | @item a tasklist which can be executed with gplmt to setup the slaves | ||
1824 | @item a master.cfg file containing a PlanetLab nodes | ||
1825 | @end itemize | ||
1826 | |||
1827 | A configuration template is included in the <contrib>, most important is | ||
1828 | that the script replaces the following tags in the template: | ||
1829 | |||
1830 | %GPLMT_BUILDER_DEFINITION :@ GPLMT_BUILDER_SUMMARY@ GPLMT_SLAVES@ | ||
1831 | %GPLMT_SCHEDULER_BUILDERS | ||
1832 | |||
1833 | Create configuration for all nodes assigned to a slice: | ||
1834 | |||
1835 | @example | ||
1836 | ./create_buildbot_configuration.py -u <planetlab username> \ | ||
1837 | -p <planetlab password> -s <slice> -m <buildmaster+port> \ | ||
1838 | -t <template> | ||
1839 | @end example | ||
1840 | |||
1841 | Create configuration for some nodes in a file: | ||
1842 | |||
1843 | @example | ||
1844 | ./create_buildbot_configuration.p -f <node_file> \ | ||
1845 | -m <buildmaster+port> -t <template> | ||
1846 | @end example | ||
1847 | |||
1848 | @item Copy the @file{master.cfg} to the buildmaster and start it | ||
1849 | Use @code{buildbot start <basedir>} to start the server | ||
1850 | @item Setup the buildslaves | ||
1851 | @end itemize | ||
1852 | |||
1853 | @c *********************************************************************** | ||
1854 | @node Why do i get an ssh error when using the regex profiler? | ||
1855 | @subsubsection Why do i get an ssh error when using the regex profiler? | ||
1856 | |||
1857 | Why do i get an ssh error "Permission denied (publickey,password)." when | ||
1858 | using the regex profiler although passwordless ssh to localhost works | ||
1859 | using publickey and ssh-agent? | ||
1860 | |||
1861 | You have to generate a public/private-key pair with no password:@ | ||
1862 | @code{ssh-keygen -t rsa -b 4096 -f ~/.ssh/id_localhost}@ | ||
1863 | and then add the following to your ~/.ssh/config file: | ||
1864 | |||
1865 | @code{Host 127.0.0.1@ IdentityFile ~/.ssh/id_localhost} | ||
1866 | |||
1867 | now make sure your hostsfile looks like | ||
1868 | |||
1869 | @example | ||
1870 | [USERNAME]@@127.0.0.1:22@ | ||
1871 | [USERNAME]@@127.0.0.1:22 | ||
1872 | @end example | ||
1873 | |||
1874 | You can test your setup by running @code{ssh 127.0.0.1} in a | ||
1875 | terminal and then in the opened session run it again. | ||
1876 | If you were not asked for a password on either login, | ||
1877 | then you should be good to go. | ||
1878 | |||
1879 | @cindex TESTBED Caveats | ||
1880 | @node TESTBED Caveats | ||
1881 | @subsection TESTBED Caveats | ||
1882 | |||
1883 | This section documents a few caveats when using the GNUnet testbed | ||
1884 | subsystem. | ||
1885 | |||
1886 | @c *********************************************************************** | ||
1887 | @menu | ||
1888 | * CORE must be started:: | ||
1889 | * ATS must want the connections:: | ||
1890 | @end menu | ||
1891 | |||
1892 | @node CORE must be started | ||
1893 | @subsubsection CORE must be started | ||
1894 | |||
1895 | A simple issue is #3993: Your configuration MUST somehow ensure that for | ||
1896 | each peer the CORE service is started when the peer is setup, otherwise | ||
1897 | TESTBED may fail to connect peers when the topology is initialized, as | ||
1898 | TESTBED will start some CORE services but not necessarily all (but it | ||
1899 | relies on all of them running). The easiest way is to set | ||
1900 | 'FORCESTART = YES' in the '[core]' section of the configuration file. | ||
1901 | Alternatively, having any service that directly or indirectly depends on | ||
1902 | CORE being started with FORCESTART will also do. This issue largely arises | ||
1903 | if users try to over-optimize by not starting any services with | ||
1904 | FORCESTART. | ||
1905 | |||
1906 | @c *********************************************************************** | ||
1907 | @node ATS must want the connections | ||
1908 | @subsubsection ATS must want the connections | ||
1909 | |||
1910 | When TESTBED sets up connections, it only offers the respective HELLO | ||
1911 | information to the TRANSPORT service. It is then up to the ATS service to | ||
1912 | @strong{decide} to use the connection. The ATS service will typically | ||
1913 | eagerly establish any connection if the number of total connections is | ||
1914 | low (relative to bandwidth). Details may further depend on the | ||
1915 | specific ATS backend that was configured. If ATS decides to NOT establish | ||
1916 | a connection (even though TESTBED provided the required information), then | ||
1917 | that connection will count as failed for TESTBED. Note that you can | ||
1918 | configure TESTBED to tolerate a certain number of connection failures | ||
1919 | (see '-e' option of gnunet-testbed-profiler). This issue largely arises | ||
1920 | for dense overlay topologies, especially if you try to create cliques | ||
1921 | with more than 20 peers. | ||
1922 | |||
1923 | @cindex libgnunetutil | ||
1924 | @node libgnunetutil | ||
1925 | @section libgnunetutil | ||
1926 | |||
1927 | libgnunetutil is the fundamental library that all GNUnet code builds upon. | ||
1928 | Ideally, this library should contain most of the platform dependent code | ||
1929 | (except for user interfaces and really special needs that only few | ||
1930 | applications have). It is also supposed to offer basic services that most | ||
1931 | if not all GNUnet binaries require. The code of libgnunetutil is in the | ||
1932 | @file{src/util/} directory. The public interface to the library is in the | ||
1933 | gnunet_util.h header. The functions provided by libgnunetutil fall | ||
1934 | roughly into the following categories (in roughly the order of importance | ||
1935 | for new developers): | ||
1936 | |||
1937 | @itemize @bullet | ||
1938 | @item logging (common_logging.c) | ||
1939 | @item memory allocation (common_allocation.c) | ||
1940 | @item endianess conversion (common_endian.c) | ||
1941 | @item internationalization (common_gettext.c) | ||
1942 | @item String manipulation (string.c) | ||
1943 | @item file access (disk.c) | ||
1944 | @item buffered disk IO (bio.c) | ||
1945 | @item time manipulation (time.c) | ||
1946 | @item configuration parsing (configuration.c) | ||
1947 | @item command-line handling (getopt*.c) | ||
1948 | @item cryptography (crypto_*.c) | ||
1949 | @item data structures (container_*.c) | ||
1950 | @item CPS-style scheduling (scheduler.c) | ||
1951 | @item Program initialization (program.c) | ||
1952 | @item Networking (network.c, client.c, server*.c, service.c) | ||
1953 | @item message queueing (mq.c) | ||
1954 | @item bandwidth calculations (bandwidth.c) | ||
1955 | @item Other OS-related (os*.c, plugin.c, signal.c) | ||
1956 | @item Pseudonym management (pseudonym.c) | ||
1957 | @end itemize | ||
1958 | |||
1959 | It should be noted that only developers that fully understand this entire | ||
1960 | API will be able to write good GNUnet code. | ||
1961 | |||
1962 | Ideally, porting GNUnet should only require porting the gnunetutil | ||
1963 | library. More testcases for the gnunetutil APIs are therefore a great | ||
1964 | way to make porting of GNUnet easier. | ||
1965 | |||
1966 | @menu | ||
1967 | * Logging:: | ||
1968 | * Interprocess communication API (IPC):: | ||
1969 | * Cryptography API:: | ||
1970 | * Message Queue API:: | ||
1971 | * Service API:: | ||
1972 | * Optimizing Memory Consumption of GNUnet's (Multi-) Hash Maps:: | ||
1973 | * CONTAINER_MDLL API:: | ||
1974 | @end menu | ||
1975 | |||
1976 | @cindex Logging | ||
1977 | @cindex log levels | ||
1978 | @node Logging | ||
1979 | @subsection Logging | ||
1980 | |||
1981 | GNUnet is able to log its activity, mostly for the purposes of debugging | ||
1982 | the program at various levels. | ||
1983 | |||
1984 | @file{gnunet_common.h} defines several @strong{log levels}: | ||
1985 | @table @asis | ||
1986 | |||
1987 | @item ERROR for errors (really problematic situations, often leading to | ||
1988 | crashes) | ||
1989 | @item WARNING for warnings (troubling situations that might have | ||
1990 | negative consequences, although not fatal) | ||
1991 | @item INFO for various information. | ||
1992 | Used somewhat rarely, as GNUnet statistics is used to hold and display | ||
1993 | most of the information that users might find interesting. | ||
1994 | @item DEBUG for debugging. | ||
1995 | Does not produce much output on normal builds, but when extra logging is | ||
1996 | enabled at compile time, a staggering amount of data is outputted under | ||
1997 | this log level. | ||
1998 | @end table | ||
1999 | |||
2000 | |||
2001 | Normal builds of GNUnet (configured with @code{--enable-logging[=yes]}) | ||
2002 | are supposed to log nothing under DEBUG level. The | ||
2003 | @code{--enable-logging=verbose} configure option can be used to create a | ||
2004 | build with all logging enabled. However, such build will produce large | ||
2005 | amounts of log data, which is inconvenient when one tries to hunt down a | ||
2006 | specific problem. | ||
2007 | |||
2008 | To mitigate this problem, GNUnet provides facilities to apply a filter to | ||
2009 | reduce the logs: | ||
2010 | @table @asis | ||
2011 | |||
2012 | @item Logging by default When no log levels are configured in any other | ||
2013 | way (see below), GNUnet will default to the WARNING log level. This | ||
2014 | mostly applies to GNUnet command line utilities, services and daemons; | ||
2015 | tests will always set log level to WARNING or, if | ||
2016 | @code{--enable-logging=verbose} was passed to configure, to DEBUG. The | ||
2017 | default level is suggested for normal operation. | ||
2018 | @item The -L option Most GNUnet executables accept an "-L loglevel" or | ||
2019 | "--log=loglevel" option. If used, it makes the process set a global log | ||
2020 | level to "loglevel". Thus it is possible to run some processes | ||
2021 | with -L DEBUG, for example, and others with -L ERROR to enable specific | ||
2022 | settings to diagnose problems with a particular process. | ||
2023 | @item Configuration files. Because GNUnet | ||
2024 | service and deamon processes are usually launched by gnunet-arm, it is not | ||
2025 | possible to pass different custom command line options directly to every | ||
2026 | one of them. The options passed to @code{gnunet-arm} only affect | ||
2027 | gnunet-arm and not the rest of GNUnet. However, one can specify a | ||
2028 | configuration key "OPTIONS" in the section that corresponds to a service | ||
2029 | or a daemon, and put a value of "-L loglevel" there. This will make the | ||
2030 | respective service or daemon set its log level to "loglevel" (as the | ||
2031 | value of OPTIONS will be passed as a command-line argument). | ||
2032 | |||
2033 | To specify the same log level for all services without creating separate | ||
2034 | "OPTIONS" entries in the configuration for each one, the user can specify | ||
2035 | a config key "GLOBAL_POSTFIX" in the [arm] section of the configuration | ||
2036 | file. The value of GLOBAL_POSTFIX will be appended to all command lines | ||
2037 | used by the ARM service to run other services. It can contain any option | ||
2038 | valid for all GNUnet commands, thus in particular the "-L loglevel" | ||
2039 | option. The ARM service itself is, however, unaffected by GLOBAL_POSTFIX; | ||
2040 | to set log level for it, one has to specify "OPTIONS" key in the [arm] | ||
2041 | section. | ||
2042 | @item Environment variables. | ||
2043 | Setting global per-process log levels with "-L loglevel" does not offer | ||
2044 | sufficient log filtering granularity, as one service will call interface | ||
2045 | libraries and supporting libraries of other GNUnet services, potentially | ||
2046 | producing lots of debug log messages from these libraries. Also, changing | ||
2047 | the config file is not always convenient (especially when running the | ||
2048 | GNUnet test suite).@ To fix that, and to allow GNUnet to use different | ||
2049 | log filtering at runtime without re-compiling the whole source tree, the | ||
2050 | log calls were changed to be configurable at run time. To configure them | ||
2051 | one has to define environment variables "GNUNET_FORCE_LOGFILE", | ||
2052 | "GNUNET_LOG" and/or "GNUNET_FORCE_LOG": | ||
2053 | @itemize @bullet | ||
2054 | |||
2055 | @item "GNUNET_LOG" only affects the logging when no global log level is | ||
2056 | configured by any other means (that is, the process does not explicitly | ||
2057 | set its own log level, there are no "-L loglevel" options on command line | ||
2058 | or in configuration files), and can be used to override the default | ||
2059 | WARNING log level. | ||
2060 | |||
2061 | @item "GNUNET_FORCE_LOG" will completely override any other log | ||
2062 | configuration options given. | ||
2063 | |||
2064 | @item "GNUNET_FORCE_LOGFILE" will completely override the location of the | ||
2065 | file to log messages to. It should contain a relative or absolute file | ||
2066 | name. Setting GNUNET_FORCE_LOGFILE is equivalent to passing | ||
2067 | "--log-file=logfile" or "-l logfile" option (see below). It supports "[]" | ||
2068 | format in file names, but not "@{@}" (see below). | ||
2069 | @end itemize | ||
2070 | |||
2071 | |||
2072 | Because environment variables are inherited by child processes when they | ||
2073 | are launched, starting or re-starting the ARM service with these | ||
2074 | variables will propagate them to all other services. | ||
2075 | |||
2076 | "GNUNET_LOG" and "GNUNET_FORCE_LOG" variables must contain a specially | ||
2077 | formatted @strong{logging definition} string, which looks like this:@ | ||
2078 | |||
2079 | @c FIXME: Can we close this with [/component] instead? | ||
2080 | @example | ||
2081 | [component];[file];[function];[from_line[-to_line]];loglevel[/component...] | ||
2082 | @end example | ||
2083 | |||
2084 | That is, a logging definition consists of definition entries, separated by | ||
2085 | slashes ('/'). If only one entry is present, there is no need to add a | ||
2086 | slash to its end (although it is not forbidden either).@ All definition | ||
2087 | fields (component, file, function, lines and loglevel) are mandatory, but | ||
2088 | (except for the loglevel) they can be empty. An empty field means | ||
2089 | "match anything". Note that even if fields are empty, the semicolon (';') | ||
2090 | separators must be present.@ The loglevel field is mandatory, and must | ||
2091 | contain one of the log level names (ERROR, WARNING, INFO or DEBUG).@ | ||
2092 | The lines field might contain one non-negative number, in which case it | ||
2093 | matches only one line, or a range "from_line-to_line", in which case it | ||
2094 | matches any line in the interval [from_line;to_line] (that is, including | ||
2095 | both start and end line).@ GNUnet mostly defaults component name to the | ||
2096 | name of the service that is implemented in a process ('transport', | ||
2097 | 'core', 'peerinfo', etc), but logging calls can specify custom component | ||
2098 | names using @code{GNUNET_log_from}.@ File name and function name are | ||
2099 | provided by the compiler (__FILE__ and __FUNCTION__ built-ins). | ||
2100 | |||
2101 | Component, file and function fields are interpreted as non-extended | ||
2102 | regular expressions (GNU libc regex functions are used). Matching is | ||
2103 | case-sensitive, "^" and "$" will match the beginning and the end of the | ||
2104 | text. If a field is empty, its contents are automatically replaced with | ||
2105 | a ".*" regular expression, which matches anything. Matching is done in | ||
2106 | the default way, which means that the expression matches as long as it's | ||
2107 | contained anywhere in the string. Thus "GNUNET_" will match both | ||
2108 | "GNUNET_foo" and "BAR_GNUNET_BAZ". Use '^' and/or '$' to make sure that | ||
2109 | the expression matches at the start and/or at the end of the string. | ||
2110 | The semicolon (';') can't be escaped, and GNUnet will not use it in | ||
2111 | component names (it can't be used in function names and file names | ||
2112 | anyway). | ||
2113 | |||
2114 | @end table | ||
2115 | |||
2116 | |||
2117 | Every logging call in GNUnet code will be (at run time) matched against | ||
2118 | the log definitions passed to the process. If a log definition fields are | ||
2119 | matching the call arguments, then the call log level is compared the the | ||
2120 | log level of that definition. If the call log level is less or equal to | ||
2121 | the definition log level, the call is allowed to proceed. Otherwise the | ||
2122 | logging call is forbidden, and nothing is logged. If no definitions | ||
2123 | matched at all, GNUnet will use the global log level or (if a global log | ||
2124 | level is not specified) will default to WARNING (that is, it will allow | ||
2125 | the call to proceed, if its level is less or equal to the global log | ||
2126 | level or to WARNING). | ||
2127 | |||
2128 | That is, definitions are evaluated from left to right, and the first | ||
2129 | matching definition is used to allow or deny the logging call. Thus it is | ||
2130 | advised to place narrow definitions at the beginning of the logdef | ||
2131 | string, and generic definitions - at the end. | ||
2132 | |||
2133 | Whether a call is allowed or not is only decided the first time this | ||
2134 | particular call is made. The evaluation result is then cached, so that | ||
2135 | any attempts to make the same call later will be allowed or disallowed | ||
2136 | right away. Because of that runtime log level evaluation should not | ||
2137 | significantly affect the process performance. | ||
2138 | Log definition parsing is only done once, at the first call to | ||
2139 | GNUNET_log_setup () made by the process (which is usually done soon after | ||
2140 | it starts). | ||
2141 | |||
2142 | At the moment of writing there is no way to specify logging definitions | ||
2143 | from configuration files, only via environment variables. | ||
2144 | |||
2145 | At the moment GNUnet will stop processing a log definition when it | ||
2146 | encounters an error in definition formatting or an error in regular | ||
2147 | expression syntax, and will not report the failure in any way. | ||
2148 | |||
2149 | |||
2150 | @c *********************************************************************** | ||
2151 | @menu | ||
2152 | * Examples:: | ||
2153 | * Log files:: | ||
2154 | * Updated behavior of GNUNET_log:: | ||
2155 | @end menu | ||
2156 | |||
2157 | @node Examples | ||
2158 | @subsubsection Examples | ||
2159 | |||
2160 | @table @asis | ||
2161 | |||
2162 | @item @code{GNUNET_FORCE_LOG=";;;;DEBUG" gnunet-arm -s} Start GNUnet | ||
2163 | process tree, running all processes with DEBUG level (one should be | ||
2164 | careful with it, as log files will grow at alarming rate!) | ||
2165 | @item @code{GNUNET_FORCE_LOG="core;;;;DEBUG" gnunet-arm -s} Start GNUnet | ||
2166 | process tree, running the core service under DEBUG level (everything else | ||
2167 | will use configured or default level). | ||
2168 | |||
2169 | @item Start GNUnet process tree, allowing any logging calls from | ||
2170 | gnunet-service-transport_validation.c (everything else will use | ||
2171 | configured or default level). | ||
2172 | |||
2173 | @example | ||
2174 | GNUNET_FORCE_LOG=";gnunet-service-transport_validation.c;;; DEBUG" \ | ||
2175 | gnunet-arm -s | ||
2176 | @end example | ||
2177 | |||
2178 | @item Start GNUnet process tree, allowing any logging calls from | ||
2179 | gnunet-gnunet-service-fs_push.c (everything else will use configured or | ||
2180 | default level). | ||
2181 | |||
2182 | @example | ||
2183 | GNUNET_FORCE_LOG="fs;gnunet-service-fs_push.c;;;DEBUG" gnunet-arm -s | ||
2184 | @end example | ||
2185 | |||
2186 | @item Start GNUnet process tree, allowing any logging calls from the | ||
2187 | GNUNET_NETWORK_socket_select function (everything else will use | ||
2188 | configured or default level). | ||
2189 | |||
2190 | @example | ||
2191 | GNUNET_FORCE_LOG=";;GNUNET_NETWORK_socket_select;;DEBUG" gnunet-arm -s | ||
2192 | @end example | ||
2193 | |||
2194 | @item Start GNUnet process tree, allowing any logging calls from the | ||
2195 | components that have "transport" in their names, and are made from | ||
2196 | function that have "send" in their names. Everything else will be allowed | ||
2197 | to be logged only if it has WARNING level. | ||
2198 | |||
2199 | @example | ||
2200 | GNUNET_FORCE_LOG="transport.*;;.*send.*;;DEBUG/;;;;WARNING" gnunet-arm -s | ||
2201 | @end example | ||
2202 | |||
2203 | @end table | ||
2204 | |||
2205 | |||
2206 | On Windows, one can use batch files to run GNUnet processes with special | ||
2207 | environment variables, without affecting the whole system. Such batch | ||
2208 | file will look like this: | ||
2209 | |||
2210 | @example | ||
2211 | set GNUNET_FORCE_LOG=;;do_transmit;;DEBUG@ gnunet-arm -s | ||
2212 | @end example | ||
2213 | |||
2214 | (note the absence of double quotes in the environment variable definition, | ||
2215 | as opposed to earlier examples, which use the shell). | ||
2216 | Another limitation, on Windows, GNUNET_FORCE_LOGFILE @strong{MUST} be set | ||
2217 | in order to GNUNET_FORCE_LOG to work. | ||
2218 | |||
2219 | |||
2220 | @cindex Log files | ||
2221 | @node Log files | ||
2222 | @subsubsection Log files | ||
2223 | |||
2224 | GNUnet can be told to log everything into a file instead of stderr (which | ||
2225 | is the default) using the "--log-file=logfile" or "-l logfile" option. | ||
2226 | This option can also be passed via command line, or from the "OPTION" and | ||
2227 | "GLOBAL_POSTFIX" configuration keys (see above). The file name passed | ||
2228 | with this option is subject to GNUnet filename expansion. If specified in | ||
2229 | "GLOBAL_POSTFIX", it is also subject to ARM service filename expansion, | ||
2230 | in particular, it may contain "@{@}" (left and right curly brace) | ||
2231 | sequence, which will be replaced by ARM with the name of the service. | ||
2232 | This is used to keep logs from more than one service separate, while only | ||
2233 | specifying one template containing "@{@}" in GLOBAL_POSTFIX. | ||
2234 | |||
2235 | As part of a secondary file name expansion, the first occurrence of "[]" | ||
2236 | sequence ("left square brace" followed by "right square brace") in the | ||
2237 | file name will be replaced with a process identifier or the process when | ||
2238 | it initializes its logging subsystem. As a result, all processes will log | ||
2239 | into different files. This is convenient for isolating messages of a | ||
2240 | particular process, and prevents I/O races when multiple processes try to | ||
2241 | write into the file at the same time. This expansion is done | ||
2242 | independently of "@{@}" expansion that ARM service does (see above). | ||
2243 | |||
2244 | The log file name that is specified via "-l" can contain format characters | ||
2245 | from the 'strftime' function family. For example, "%Y" will be replaced | ||
2246 | with the current year. Using "basename-%Y-%m-%d.log" would include the | ||
2247 | current year, month and day in the log file. If a GNUnet process runs for | ||
2248 | long enough to need more than one log file, it will eventually clean up | ||
2249 | old log files. Currently, only the last three log files (plus the current | ||
2250 | log file) are preserved. So once the fifth log file goes into use (so | ||
2251 | after 4 days if you use "%Y-%m-%d" as above), the first log file will be | ||
2252 | automatically deleted. Note that if your log file name only contains "%Y", | ||
2253 | then log files would be kept for 4 years and the logs from the first year | ||
2254 | would be deleted once year 5 begins. If you do not use any date-related | ||
2255 | string format codes, logs would never be automatically deleted by GNUnet. | ||
2256 | |||
2257 | |||
2258 | @c *********************************************************************** | ||
2259 | |||
2260 | @node Updated behavior of GNUNET_log | ||
2261 | @subsubsection Updated behavior of GNUNET_log | ||
2262 | |||
2263 | It's currently quite common to see constructions like this all over the | ||
2264 | code: | ||
2265 | |||
2266 | @example | ||
2267 | #if MESH_DEBUG | ||
2268 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "MESH: client disconnected\n"); | ||
2269 | #endif | ||
2270 | @end example | ||
2271 | |||
2272 | The reason for the #if is not to avoid displaying the message when | ||
2273 | disabled (GNUNET_ERROR_TYPE takes care of that), but to avoid the | ||
2274 | compiler including it in the binary at all, when compiling GNUnet for | ||
2275 | platforms with restricted storage space / memory (MIPS routers, | ||
2276 | ARM plug computers / dev boards, etc). | ||
2277 | |||
2278 | This presents several problems: the code gets ugly, hard to write and it | ||
2279 | is very easy to forget to include the #if guards, creating non-consistent | ||
2280 | code. A new change in GNUNET_log aims to solve these problems. | ||
2281 | |||
2282 | @strong{This change requires to @file{./configure} with at least | ||
2283 | @code{--enable-logging=verbose} to see debug messages.} | ||
2284 | |||
2285 | Here is an example of code with dense debug statements: | ||
2286 | |||
2287 | @example | ||
2288 | switch (restrict_topology) @{ | ||
2289 | case GNUNET_TESTING_TOPOLOGY_CLIQUE:#if VERBOSE_TESTING | ||
2290 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, _("Blacklisting all but clique | ||
2291 | topology\n")); #endif unblacklisted_connections = create_clique (pg, | ||
2292 | &remove_connections, BLACKLIST, GNUNET_NO); break; case | ||
2293 | GNUNET_TESTING_TOPOLOGY_SMALL_WORLD_RING: #if VERBOSE_TESTING GNUNET_log | ||
2294 | (GNUNET_ERROR_TYPE_DEBUG, _("Blacklisting all but small world (ring) | ||
2295 | topology\n")); #endif unblacklisted_connections = create_small_world_ring | ||
2296 | (pg,&remove_connections, BLACKLIST); break; | ||
2297 | @end example | ||
2298 | |||
2299 | |||
2300 | Pretty hard to follow, huh? | ||
2301 | |||
2302 | From now on, it is not necessary to include the #if / #endif statements to | ||
2303 | achieve the same behavior. The GNUNET_log and GNUNET_log_from macros take | ||
2304 | care of it for you, depending on the configure option: | ||
2305 | |||
2306 | @itemize @bullet | ||
2307 | @item If @code{--enable-logging} is set to @code{no}, the binary will | ||
2308 | contain no log messages at all. | ||
2309 | @item If @code{--enable-logging} is set to @code{yes}, the binary will | ||
2310 | contain no DEBUG messages, and therefore running with -L DEBUG will have | ||
2311 | no effect. Other messages (ERROR, WARNING, INFO, etc) will be included. | ||
2312 | @item If @code{--enable-logging} is set to @code{verbose}, or | ||
2313 | @code{veryverbose} the binary will contain DEBUG messages (still, it will | ||
2314 | be neccessary to run with -L DEBUG or set the DEBUG config option to show | ||
2315 | them). | ||
2316 | @end itemize | ||
2317 | |||
2318 | |||
2319 | If you are a developer: | ||
2320 | @itemize @bullet | ||
2321 | @item please make sure that you @code{./configure | ||
2322 | --enable-logging=@{verbose,veryverbose@}}, so you can see DEBUG messages. | ||
2323 | @item please remove the @code{#if} statements around @code{GNUNET_log | ||
2324 | (GNUNET_ERROR_TYPE_DEBUG, ...)} lines, to improve the readibility of your | ||
2325 | code. | ||
2326 | @end itemize | ||
2327 | |||
2328 | Since now activating DEBUG automatically makes it VERBOSE and activates | ||
2329 | @strong{all} debug messages by default, you probably want to use the | ||
2330 | https://gnunet.org/logging functionality to filter only relevant messages. | ||
2331 | A suitable configuration could be: | ||
2332 | |||
2333 | @example | ||
2334 | $ export GNUNET_FORCE_LOG="^YOUR_SUBSYSTEM$;;;;DEBUG/;;;;WARNING" | ||
2335 | @end example | ||
2336 | |||
2337 | Which will behave almost like enabling DEBUG in that subsytem before the | ||
2338 | change. Of course you can adapt it to your particular needs, this is only | ||
2339 | a quick example. | ||
2340 | |||
2341 | @cindex Interprocess communication API | ||
2342 | @cindex ICP | ||
2343 | @node Interprocess communication API (IPC) | ||
2344 | @subsection Interprocess communication API (IPC) | ||
2345 | |||
2346 | In GNUnet a variety of new message types might be defined and used in | ||
2347 | interprocess communication, in this tutorial we use the | ||
2348 | @code{struct AddressLookupMessage} as a example to introduce how to | ||
2349 | construct our own message type in GNUnet and how to implement the message | ||
2350 | communication between service and client. | ||
2351 | (Here, a client uses the @code{struct AddressLookupMessage} as a request | ||
2352 | to ask the server to return the address of any other peer connecting to | ||
2353 | the service.) | ||
2354 | |||
2355 | |||
2356 | @c *********************************************************************** | ||
2357 | @menu | ||
2358 | * Define new message types:: | ||
2359 | * Define message struct:: | ||
2360 | * Client - Establish connection:: | ||
2361 | * Client - Initialize request message:: | ||
2362 | * Client - Send request and receive response:: | ||
2363 | * Server - Startup service:: | ||
2364 | * Server - Add new handles for specified messages:: | ||
2365 | * Server - Process request message:: | ||
2366 | * Server - Response to client:: | ||
2367 | * Server - Notification of clients:: | ||
2368 | * Conversion between Network Byte Order (Big Endian) and Host Byte Order:: | ||
2369 | @end menu | ||
2370 | |||
2371 | @node Define new message types | ||
2372 | @subsubsection Define new message types | ||
2373 | |||
2374 | First of all, you should define the new message type in | ||
2375 | @file{gnunet_protocols.h}: | ||
2376 | |||
2377 | @example | ||
2378 | // Request to look addresses of peers in server. | ||
2379 | #define GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_LOOKUP 29 | ||
2380 | // Response to the address lookup request. | ||
2381 | #define GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_REPLY 30 | ||
2382 | @end example | ||
2383 | |||
2384 | @c *********************************************************************** | ||
2385 | @node Define message struct | ||
2386 | @subsubsection Define message struct | ||
2387 | |||
2388 | After the type definition, the specified message structure should also be | ||
2389 | described in the header file, e.g. transport.h in our case. | ||
2390 | |||
2391 | @example | ||
2392 | struct AddressLookupMessage @{ | ||
2393 | struct GNUNET_MessageHeader header; | ||
2394 | int32_t numeric_only GNUNET_PACKED; | ||
2395 | struct GNUNET_TIME_AbsoluteNBO timeout; | ||
2396 | uint32_t addrlen GNUNET_PACKED; | ||
2397 | /* followed by 'addrlen' bytes of the actual address, then | ||
2398 | followed by the 0-terminated name of the transport */ @}; | ||
2399 | GNUNET_NETWORK_STRUCT_END | ||
2400 | @end example | ||
2401 | |||
2402 | |||
2403 | Please note @code{GNUNET_NETWORK_STRUCT_BEGIN} and @code{GNUNET_PACKED} | ||
2404 | which both ensure correct alignment when sending structs over the network. | ||
2405 | |||
2406 | @menu | ||
2407 | @end menu | ||
2408 | |||
2409 | @c *********************************************************************** | ||
2410 | @node Client - Establish connection | ||
2411 | @subsubsection Client - Establish connection | ||
2412 | @c %**end of header | ||
2413 | |||
2414 | |||
2415 | At first, on the client side, the underlying API is employed to create a | ||
2416 | new connection to a service, in our example the transport service would be | ||
2417 | connected. | ||
2418 | |||
2419 | @example | ||
2420 | struct GNUNET_CLIENT_Connection *client; | ||
2421 | client = GNUNET_CLIENT_connect ("transport", cfg); | ||
2422 | @end example | ||
2423 | |||
2424 | @c *********************************************************************** | ||
2425 | @node Client - Initialize request message | ||
2426 | @subsubsection Client - Initialize request message | ||
2427 | @c %**end of header | ||
2428 | |||
2429 | When the connection is ready, we initialize the message. In this step, | ||
2430 | all the fields of the message should be properly initialized, namely the | ||
2431 | size, type, and some extra user-defined data, such as timeout, name of | ||
2432 | transport, address and name of transport. | ||
2433 | |||
2434 | @example | ||
2435 | struct AddressLookupMessage *msg; | ||
2436 | size_t len = sizeof (struct AddressLookupMessage) | ||
2437 | + addressLen | ||
2438 | + strlen (nameTrans) | ||
2439 | + 1; | ||
2440 | msg->header->size = htons (len); | ||
2441 | msg->header->type = htons | ||
2442 | (GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_LOOKUP); | ||
2443 | msg->timeout = GNUNET_TIME_absolute_hton (abs_timeout); | ||
2444 | msg->addrlen = htonl (addressLen); | ||
2445 | char *addrbuf = (char *) &msg[1]; | ||
2446 | memcpy (addrbuf, address, addressLen); | ||
2447 | char *tbuf = &addrbuf[addressLen]; | ||
2448 | memcpy (tbuf, nameTrans, strlen (nameTrans) + 1); | ||
2449 | @end example | ||
2450 | |||
2451 | Note that, here the functions @code{htonl}, @code{htons} and | ||
2452 | @code{GNUNET_TIME_absolute_hton} are applied to convert little endian | ||
2453 | into big endian, about the usage of the big/small edian order and the | ||
2454 | corresponding conversion function please refer to Introduction of | ||
2455 | Big Endian and Little Endian. | ||
2456 | |||
2457 | @c *********************************************************************** | ||
2458 | @node Client - Send request and receive response | ||
2459 | @subsubsection Client - Send request and receive response | ||
2460 | @c %**end of header | ||
2461 | |||
2462 | @b{FIXME: This is very outdated, see the tutorial for the current API!} | ||
2463 | |||
2464 | Next, the client would send the constructed message as a request to the | ||
2465 | service and wait for the response from the service. To accomplish this | ||
2466 | goal, there are a number of API calls that can be used. In this example, | ||
2467 | @code{GNUNET_CLIENT_transmit_and_get_response} is chosen as the most | ||
2468 | appropriate function to use. | ||
2469 | |||
2470 | @example | ||
2471 | GNUNET_CLIENT_transmit_and_get_response | ||
2472 | (client, msg->header, timeout, GNUNET_YES, &address_response_processor, | ||
2473 | arp_ctx); | ||
2474 | @end example | ||
2475 | |||
2476 | the argument @code{address_response_processor} is a function with | ||
2477 | @code{GNUNET_CLIENT_MessageHandler} type, which is used to process the | ||
2478 | reply message from the service. | ||
2479 | |||
2480 | @node Server - Startup service | ||
2481 | @subsubsection Server - Startup service | ||
2482 | |||
2483 | After receiving the request message, we run a standard GNUnet service | ||
2484 | startup sequence using @code{GNUNET_SERVICE_run}, as follows, | ||
2485 | |||
2486 | @example | ||
2487 | int main(int argc, char**argv) @{ | ||
2488 | GNUNET_SERVICE_run(argc, argv, "transport" | ||
2489 | GNUNET_SERVICE_OPTION_NONE, &run, NULL)); @} | ||
2490 | @end example | ||
2491 | |||
2492 | @c *********************************************************************** | ||
2493 | @node Server - Add new handles for specified messages | ||
2494 | @subsubsection Server - Add new handles for specified messages | ||
2495 | @c %**end of header | ||
2496 | |||
2497 | in the function above the argument @code{run} is used to initiate | ||
2498 | transport service,and defined like this: | ||
2499 | |||
2500 | @example | ||
2501 | static void run (void *cls, | ||
2502 | struct GNUNET_SERVER_Handle *serv, | ||
2503 | const struct GNUNET_CONFIGURATION_Handle *cfg) @{ | ||
2504 | GNUNET_SERVER_add_handlers (serv, handlers); @} | ||
2505 | @end example | ||
2506 | |||
2507 | |||
2508 | Here, @code{GNUNET_SERVER_add_handlers} must be called in the run | ||
2509 | function to add new handlers in the service. The parameter | ||
2510 | @code{handlers} is a list of @code{struct GNUNET_SERVER_MessageHandler} | ||
2511 | to tell the service which function should be called when a particular | ||
2512 | type of message is received, and should be defined in this way: | ||
2513 | |||
2514 | @example | ||
2515 | static struct GNUNET_SERVER_MessageHandler handlers[] = @{ | ||
2516 | @{&handle_start, | ||
2517 | NULL, | ||
2518 | GNUNET_MESSAGE_TYPE_TRANSPORT_START, | ||
2519 | 0@}, | ||
2520 | @{&handle_send, | ||
2521 | NULL, | ||
2522 | GNUNET_MESSAGE_TYPE_TRANSPORT_SEND, | ||
2523 | 0@}, | ||
2524 | @{&handle_try_connect, | ||
2525 | NULL, | ||
2526 | GNUNET_MESSAGE_TYPE_TRANSPORT_TRY_CONNECT, | ||
2527 | sizeof (struct TryConnectMessage) | ||
2528 | @}, | ||
2529 | @{&handle_address_lookup, | ||
2530 | NULL, | ||
2531 | GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_LOOKUP, | ||
2532 | 0@}, | ||
2533 | @{NULL, | ||
2534 | NULL, | ||
2535 | 0, | ||
2536 | 0@} | ||
2537 | @}; | ||
2538 | @end example | ||
2539 | |||
2540 | |||
2541 | As shown, the first member of the struct in the first area is a callback | ||
2542 | function, which is called to process the specified message types, given | ||
2543 | as the third member. The second parameter is the closure for the callback | ||
2544 | function, which is set to @code{NULL} in most cases, and the last | ||
2545 | parameter is the expected size of the message of this type, usually we | ||
2546 | set it to 0 to accept variable size, for special cases the exact size of | ||
2547 | the specified message also can be set. In addition, the terminator sign | ||
2548 | depicted as @code{@{NULL, NULL, 0, 0@}} is set in the last aera. | ||
2549 | |||
2550 | @c *********************************************************************** | ||
2551 | @node Server - Process request message | ||
2552 | @subsubsection Server - Process request message | ||
2553 | @c %**end of header | ||
2554 | |||
2555 | After the initialization of transport service, the request message would | ||
2556 | be processed. Before handling the main message data, the validity of this | ||
2557 | message should be checked out, e.g., to check whether the size of message | ||
2558 | is correct. | ||
2559 | |||
2560 | @example | ||
2561 | size = ntohs (message->size); | ||
2562 | if (size < sizeof (struct AddressLookupMessage)) @{ | ||
2563 | GNUNET_break_op (0); | ||
2564 | GNUNET_SERVER_receive_done (client, GNUNET_SYSERR); | ||
2565 | return; @} | ||
2566 | @end example | ||
2567 | |||
2568 | |||
2569 | Note that, opposite to the construction method of the request message in | ||
2570 | the client, in the server the function @code{nothl} and @code{ntohs} | ||
2571 | should be employed during the extraction of the data from the message, so | ||
2572 | that the data in big endian order can be converted back into little | ||
2573 | endian order. See more in detail please refer to Introduction of | ||
2574 | Big Endian and Little Endian. | ||
2575 | |||
2576 | Moreover in this example, the name of the transport stored in the message | ||
2577 | is a 0-terminated string, so we should also check whether the name of the | ||
2578 | transport in the received message is 0-terminated: | ||
2579 | |||
2580 | @example | ||
2581 | nameTransport = (const char *) &address[addressLen]; | ||
2582 | if (nameTransport[size - sizeof | ||
2583 | (struct AddressLookupMessage) | ||
2584 | - addressLen - 1] != '\0') @{ | ||
2585 | GNUNET_break_op (0); | ||
2586 | GNUNET_SERVER_receive_done (client, | ||
2587 | GNUNET_SYSERR); | ||
2588 | return; @} | ||
2589 | @end example | ||
2590 | |||
2591 | Here, @code{GNUNET_SERVER_receive_done} should be called to tell the | ||
2592 | service that the request is done and can receive the next message. The | ||
2593 | argument @code{GNUNET_SYSERR} here indicates that the service didn't | ||
2594 | understand the request message, and the processing of this request would | ||
2595 | be terminated. | ||
2596 | |||
2597 | In comparison to the aforementioned situation, when the argument is equal | ||
2598 | to @code{GNUNET_OK}, the service would continue to process the requst | ||
2599 | message. | ||
2600 | |||
2601 | @c *********************************************************************** | ||
2602 | @node Server - Response to client | ||
2603 | @subsubsection Server - Response to client | ||
2604 | @c %**end of header | ||
2605 | |||
2606 | Once the processing of current request is done, the server should give the | ||
2607 | response to the client. A new @code{struct AddressLookupMessage} would be | ||
2608 | produced by the server in a similar way as the client did and sent to the | ||
2609 | client, but here the type should be | ||
2610 | @code{GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_REPLY} rather than | ||
2611 | @code{GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_LOOKUP} in client. | ||
2612 | @example | ||
2613 | struct AddressLookupMessage *msg; | ||
2614 | size_t len = sizeof (struct AddressLookupMessage) | ||
2615 | + addressLen | ||
2616 | + strlen (nameTrans) + 1; | ||
2617 | msg->header->size = htons (len); | ||
2618 | msg->header->type = htons | ||
2619 | (GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_REPLY); | ||
2620 | |||
2621 | // ... | ||
2622 | |||
2623 | struct GNUNET_SERVER_TransmitContext *tc; | ||
2624 | tc = GNUNET_SERVER_transmit_context_create (client); | ||
2625 | GNUNET_SERVER_transmit_context_append_data | ||
2626 | (tc, | ||
2627 | NULL, | ||
2628 | 0, | ||
2629 | GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_REPLY); | ||
2630 | GNUNET_SERVER_transmit_context_run (tc, rtimeout); | ||
2631 | @end example | ||
2632 | |||
2633 | |||
2634 | Note that, there are also a number of other APIs provided to the service | ||
2635 | to send the message. | ||
2636 | |||
2637 | @c *********************************************************************** | ||
2638 | @node Server - Notification of clients | ||
2639 | @subsubsection Server - Notification of clients | ||
2640 | @c %**end of header | ||
2641 | |||
2642 | Often a service needs to (repeatedly) transmit notifications to a client | ||
2643 | or a group of clients. In these cases, the client typically has once | ||
2644 | registered for a set of events and then needs to receive a message | ||
2645 | whenever such an event happens (until the client disconnects). The use of | ||
2646 | a notification context can help manage message queues to clients and | ||
2647 | handle disconnects. Notification contexts can be used to send | ||
2648 | individualized messages to a particular client or to broadcast messages | ||
2649 | to a group of clients. An individualized notification might look like | ||
2650 | this: | ||
2651 | |||
2652 | @example | ||
2653 | GNUNET_SERVER_notification_context_unicast(nc, | ||
2654 | client, | ||
2655 | msg, | ||
2656 | GNUNET_YES); | ||
2657 | @end example | ||
2658 | |||
2659 | |||
2660 | Note that after processing the original registration message for | ||
2661 | notifications, the server code still typically needs to call | ||
2662 | @code{GNUNET_SERVER_receive_done} so that the client can transmit further | ||
2663 | messages to the server. | ||
2664 | |||
2665 | @c *********************************************************************** | ||
2666 | @node Conversion between Network Byte Order (Big Endian) and Host Byte Order | ||
2667 | @subsubsection Conversion between Network Byte Order (Big Endian) and Host Byte Order | ||
2668 | @c %** subsub? it's a referenced page on the ipc document. | ||
2669 | @c %**end of header | ||
2670 | |||
2671 | Here we can simply comprehend big endian and little endian as Network Byte | ||
2672 | Order and Host Byte Order respectively. What is the difference between | ||
2673 | both two? | ||
2674 | |||
2675 | Usually in our host computer we store the data byte as Host Byte Order, | ||
2676 | for example, we store a integer in the RAM which might occupies 4 Byte, | ||
2677 | as Host Byte Order the higher Byte would be stored at the lower address | ||
2678 | of RAM, and the lower Byte would be stored at the higher address of RAM. | ||
2679 | However, contrast to this, Network Byte Order just take the totally | ||
2680 | opposite way to store the data, says, it will store the lower Byte at the | ||
2681 | lower address, and the higher Byte will stay at higher address. | ||
2682 | |||
2683 | For the current communication of network, we normally exchange the | ||
2684 | information by surveying the data package, every two host wants to | ||
2685 | communicate with each other must send and receive data package through | ||
2686 | network. In order to maintain the identity of data through the | ||
2687 | transmission in the network, the order of the Byte storage must changed | ||
2688 | before sending and after receiving the data. | ||
2689 | |||
2690 | There ten convenient functions to realize the conversion of Byte Order in | ||
2691 | GNUnet, as following: | ||
2692 | |||
2693 | @table @asis | ||
2694 | |||
2695 | @item uint16_t htons(uint16_t hostshort) Convert host byte order to net | ||
2696 | byte order with short int | ||
2697 | @item uint32_t htonl(uint32_t hostlong) Convert host byte | ||
2698 | order to net byte order with long int | ||
2699 | @item uint16_t ntohs(uint16_t netshort) | ||
2700 | Convert net byte order to host byte order with short int | ||
2701 | @item uint32_t | ||
2702 | ntohl(uint32_t netlong) Convert net byte order to host byte order with | ||
2703 | long int | ||
2704 | @item unsigned long long GNUNET_ntohll (unsigned long long netlonglong) | ||
2705 | Convert net byte order to host byte order with long long int | ||
2706 | @item unsigned long long GNUNET_htonll (unsigned long long hostlonglong) | ||
2707 | Convert host byte order to net byte order with long long int | ||
2708 | @item struct GNUNET_TIME_RelativeNBO GNUNET_TIME_relative_hton | ||
2709 | (struct GNUNET_TIME_Relative a) Convert relative time to network byte | ||
2710 | order. | ||
2711 | @item struct GNUNET_TIME_Relative GNUNET_TIME_relative_ntoh | ||
2712 | (struct GNUNET_TIME_RelativeNBO a) Convert relative time from network | ||
2713 | byte order. | ||
2714 | @item struct GNUNET_TIME_AbsoluteNBO GNUNET_TIME_absolute_hton | ||
2715 | (struct GNUNET_TIME_Absolute a) Convert relative time to network byte | ||
2716 | order. | ||
2717 | @item struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_ntoh | ||
2718 | (struct GNUNET_TIME_AbsoluteNBO a) Convert relative time from network | ||
2719 | byte order. | ||
2720 | @end table | ||
2721 | |||
2722 | @cindex Cryptography API | ||
2723 | @node Cryptography API | ||
2724 | @subsection Cryptography API | ||
2725 | @c %**end of header | ||
2726 | |||
2727 | The gnunetutil APIs provides the cryptographic primitives used in GNUnet. | ||
2728 | GNUnet uses 2048 bit RSA keys for the session key exchange and for signing | ||
2729 | messages by peers and most other public-key operations. Most researchers | ||
2730 | in cryptography consider 2048 bit RSA keys as secure and practically | ||
2731 | unbreakable for a long time. The API provides functions to create a fresh | ||
2732 | key pair, read a private key from a file (or create a new file if the | ||
2733 | file does not exist), encrypt, decrypt, sign, verify and extraction of | ||
2734 | the public key into a format suitable for network transmission. | ||
2735 | |||
2736 | For the encryption of files and the actual data exchanged between peers | ||
2737 | GNUnet uses 256-bit AES encryption. Fresh, session keys are negotiated | ||
2738 | for every new connection.@ Again, there is no published technique to | ||
2739 | break this cipher in any realistic amount of time. The API provides | ||
2740 | functions for generation of keys, validation of keys (important for | ||
2741 | checking that decryptions using RSA succeeded), encryption and decryption. | ||
2742 | |||
2743 | GNUnet uses SHA-512 for computing one-way hash codes. The API provides | ||
2744 | functions to compute a hash over a block in memory or over a file on disk. | ||
2745 | |||
2746 | The crypto API also provides functions for randomizing a block of memory, | ||
2747 | obtaining a single random number and for generating a permuation of the | ||
2748 | numbers 0 to n-1. Random number generation distinguishes between WEAK and | ||
2749 | STRONG random number quality; WEAK random numbers are pseudo-random | ||
2750 | whereas STRONG random numbers use entropy gathered from the operating | ||
2751 | system. | ||
2752 | |||
2753 | Finally, the crypto API provides a means to deterministically generate a | ||
2754 | 1024-bit RSA key from a hash code. These functions should most likely not | ||
2755 | be used by most applications; most importantly, | ||
2756 | GNUNET_CRYPTO_rsa_key_create_from_hash does not create an RSA-key that | ||
2757 | should be considered secure for traditional applications of RSA. | ||
2758 | |||
2759 | @cindex Message Queue API | ||
2760 | @node Message Queue API | ||
2761 | @subsection Message Queue API | ||
2762 | @c %**end of header | ||
2763 | |||
2764 | @strong{ Introduction }@ | ||
2765 | Often, applications need to queue messages that | ||
2766 | are to be sent to other GNUnet peers, clients or services. As all of | ||
2767 | GNUnet's message-based communication APIs, by design, do not allow | ||
2768 | messages to be queued, it is common to implement custom message queues | ||
2769 | manually when they are needed. However, writing very similar code in | ||
2770 | multiple places is tedious and leads to code duplication. | ||
2771 | |||
2772 | MQ (for Message Queue) is an API that provides the functionality to | ||
2773 | implement and use message queues. We intend to eventually replace all of | ||
2774 | the custom message queue implementations in GNUnet with MQ. | ||
2775 | |||
2776 | @strong{ Basic Concepts }@ | ||
2777 | The two most important entities in MQ are queues and envelopes. | ||
2778 | |||
2779 | Every queue is backed by a specific implementation (e.g. for mesh, stream, | ||
2780 | connection, server client, etc.) that will actually deliver the queued | ||
2781 | messages. For convenience,@ some queues also allow to specify a list of | ||
2782 | message handlers. The message queue will then also wait for incoming | ||
2783 | messages and dispatch them appropriately. | ||
2784 | |||
2785 | An envelope holds the the memory for a message, as well as metadata | ||
2786 | (Where is the envelope queued? What should happen after it has been | ||
2787 | sent?). Any envelope can only be queued in one message queue. | ||
2788 | |||
2789 | @strong{ Creating Queues }@ | ||
2790 | The following is a list of currently available message queues. Note that | ||
2791 | to avoid layering issues, message queues for higher level APIs are not | ||
2792 | part of @code{libgnunetutil}, but@ the respective API itself provides the | ||
2793 | queue implementation. | ||
2794 | |||
2795 | @table @asis | ||
2796 | |||
2797 | @item @code{GNUNET_MQ_queue_for_connection_client} | ||
2798 | Transmits queued messages over a @code{GNUNET_CLIENT_Connection} handle. | ||
2799 | Also supports receiving with message handlers. | ||
2800 | |||
2801 | @item @code{GNUNET_MQ_queue_for_server_client} | ||
2802 | Transmits queued messages over a @code{GNUNET_SERVER_Client} handle. Does | ||
2803 | not support incoming message handlers. | ||
2804 | |||
2805 | @item @code{GNUNET_MESH_mq_create} Transmits queued messages over a | ||
2806 | @code{GNUNET_MESH_Tunnel} handle. Does not support incoming message | ||
2807 | handlers. | ||
2808 | |||
2809 | @item @code{GNUNET_MQ_queue_for_callbacks} This is the most general | ||
2810 | implementation. Instead of delivering and receiving messages with one of | ||
2811 | GNUnet's communication APIs, implementation callbacks are called. Refer to | ||
2812 | "Implementing Queues" for a more detailed explanation. | ||
2813 | @end table | ||
2814 | |||
2815 | |||
2816 | @strong{ Allocating Envelopes }@ | ||
2817 | A GNUnet message (as defined by the GNUNET_MessageHeader) has three | ||
2818 | parts: The size, the type, and the body. | ||
2819 | |||
2820 | MQ provides macros to allocate an envelope containing a message | ||
2821 | conveniently, automatically setting the size and type fields of the | ||
2822 | message. | ||
2823 | |||
2824 | Consider the following simple message, with the body consisting of a | ||
2825 | single number value. | ||
2826 | @c why the empy code function? | ||
2827 | @code{} | ||
2828 | |||
2829 | @example | ||
2830 | struct NumberMessage @{ | ||
2831 | /** Type: GNUNET_MESSAGE_TYPE_EXAMPLE_1 */ | ||
2832 | struct GNUNET_MessageHeader header; | ||
2833 | uint32_t number GNUNET_PACKED; | ||
2834 | @}; | ||
2835 | @end example | ||
2836 | |||
2837 | An envelope containing an instance of the NumberMessage can be | ||
2838 | constructed like this: | ||
2839 | |||
2840 | @example | ||
2841 | struct GNUNET_MQ_Envelope *ev; | ||
2842 | struct NumberMessage *msg; | ||
2843 | ev = GNUNET_MQ_msg (msg, GNUNET_MESSAGE_TYPE_EXAMPLE_1); | ||
2844 | msg->number = htonl (42); | ||
2845 | @end example | ||
2846 | |||
2847 | In the above code, @code{GNUNET_MQ_msg} is a macro. The return value is | ||
2848 | the newly allocated envelope. The first argument must be a pointer to some | ||
2849 | @code{struct} containing a @code{struct GNUNET_MessageHeader header} | ||
2850 | field, while the second argument is the desired message type, in host | ||
2851 | byte order. | ||
2852 | |||
2853 | The @code{msg} pointer now points to an allocated message, where the | ||
2854 | message type and the message size are already set. The message's size is | ||
2855 | inferred from the type of the @code{msg} pointer: It will be set to | ||
2856 | 'sizeof(*msg)', properly converted to network byte order. | ||
2857 | |||
2858 | If the message body's size is dynamic, the the macro | ||
2859 | @code{GNUNET_MQ_msg_extra} can be used to allocate an envelope whose | ||
2860 | message has additional space allocated after the @code{msg} structure. | ||
2861 | |||
2862 | If no structure has been defined for the message, | ||
2863 | @code{GNUNET_MQ_msg_header_extra} can be used to allocate additional space | ||
2864 | after the message header. The first argument then must be a pointer to a | ||
2865 | @code{GNUNET_MessageHeader}. | ||
2866 | |||
2867 | @strong{Envelope Properties}@ | ||
2868 | A few functions in MQ allow to set additional properties on envelopes: | ||
2869 | |||
2870 | @table @asis | ||
2871 | |||
2872 | @item @code{GNUNET_MQ_notify_sent} Allows to specify a function that will | ||
2873 | be called once the envelope's message has been sent irrevocably. | ||
2874 | An envelope can be canceled precisely up to the@ point where the notify | ||
2875 | sent callback has been called. | ||
2876 | |||
2877 | @item @code{GNUNET_MQ_disable_corking} No corking will be used when | ||
2878 | sending the message. Not every@ queue supports this flag, per default, | ||
2879 | envelopes are sent with corking.@ | ||
2880 | |||
2881 | @end table | ||
2882 | |||
2883 | |||
2884 | @strong{Sending Envelopes}@ | ||
2885 | Once an envelope has been constructed, it can be queued for sending with | ||
2886 | @code{GNUNET_MQ_send}. | ||
2887 | |||
2888 | Note that in order to avoid memory leaks, an envelope must either be sent | ||
2889 | (the queue will free it) or destroyed explicitly with | ||
2890 | @code{GNUNET_MQ_discard}. | ||
2891 | |||
2892 | @strong{Canceling Envelopes}@ | ||
2893 | An envelope queued with @code{GNUNET_MQ_send} can be canceled with | ||
2894 | @code{GNUNET_MQ_cancel}. Note that after the notify sent callback has | ||
2895 | been called, canceling a message results in undefined behavior. | ||
2896 | Thus it is unsafe to cancel an envelope that does not have a notify sent | ||
2897 | callback. When canceling an envelope, it is not necessary@ to call | ||
2898 | @code{GNUNET_MQ_discard}, and the envelope can't be sent again. | ||
2899 | |||
2900 | @strong{ Implementing Queues }@ | ||
2901 | @code{TODO} | ||
2902 | |||
2903 | @cindex Service API | ||
2904 | @node Service API | ||
2905 | @subsection Service API | ||
2906 | @c %**end of header | ||
2907 | |||
2908 | Most GNUnet code lives in the form of services. Services are processes | ||
2909 | that offer an API for other components of the system to build on. Those | ||
2910 | other components can be command-line tools for users, graphical user | ||
2911 | interfaces or other services. Services provide their API using an IPC | ||
2912 | protocol. For this, each service must listen on either a TCP port or a | ||
2913 | UNIX domain socket; for this, the service implementation uses the server | ||
2914 | API. This use of server is exposed directly to the users of the service | ||
2915 | API. Thus, when using the service API, one is usually also often using | ||
2916 | large parts of the server API. The service API provides various | ||
2917 | convenience functions, such as parsing command-line arguments and the | ||
2918 | configuration file, which are not found in the server API. | ||
2919 | The dual to the service/server API is the client API, which can be used to | ||
2920 | access services. | ||
2921 | |||
2922 | The most common way to start a service is to use the | ||
2923 | @code{GNUNET_SERVICE_run} function from the program's main function. | ||
2924 | @code{GNUNET_SERVICE_run} will then parse the command line and | ||
2925 | configuration files and, based on the options found there, | ||
2926 | start the server. It will then give back control to the main | ||
2927 | program, passing the server and the configuration to the | ||
2928 | @code{GNUNET_SERVICE_Main} callback. @code{GNUNET_SERVICE_run} | ||
2929 | will also take care of starting the scheduler loop. | ||
2930 | If this is inappropriate (for example, because the scheduler loop | ||
2931 | is already running), @code{GNUNET_SERVICE_start} and | ||
2932 | related functions provide an alternative to @code{GNUNET_SERVICE_run}. | ||
2933 | |||
2934 | When starting a service, the service_name option is used to determine | ||
2935 | which sections in the configuration file should be used to configure the | ||
2936 | service. A typical value here is the name of the @file{src/} | ||
2937 | sub-directory, for example @file{statistics}. | ||
2938 | The same string would also be given to | ||
2939 | @code{GNUNET_CLIENT_connect} to access the service. | ||
2940 | |||
2941 | Once a service has been initialized, the program should use the | ||
2942 | @code{GNUNET_SERVICE_Main} callback to register message handlers | ||
2943 | using @code{GNUNET_SERVER_add_handlers}. | ||
2944 | The service will already have registered a handler for the | ||
2945 | "TEST" message. | ||
2946 | |||
2947 | @fnindex GNUNET_SERVICE_Options | ||
2948 | The option bitfield (@code{enum GNUNET_SERVICE_Options}) | ||
2949 | determines how a service should behave during shutdown. | ||
2950 | There are three key strategies: | ||
2951 | |||
2952 | @table @asis | ||
2953 | |||
2954 | @item instant (@code{GNUNET_SERVICE_OPTION_NONE}) | ||
2955 | Upon receiving the shutdown | ||
2956 | signal from the scheduler, the service immediately terminates the server, | ||
2957 | closing all existing connections with clients. | ||
2958 | @item manual (@code{GNUNET_SERVICE_OPTION_MANUAL_SHUTDOWN}) | ||
2959 | The service does nothing by itself | ||
2960 | during shutdown. The main program will need to take the appropriate | ||
2961 | action by calling GNUNET_SERVER_destroy or GNUNET_SERVICE_stop (depending | ||
2962 | on how the service was initialized) to terminate the service. This method | ||
2963 | is used by gnunet-service-arm and rather uncommon. | ||
2964 | @item soft (@code{GNUNET_SERVICE_OPTION_SOFT_SHUTDOWN}) | ||
2965 | Upon receiving the shutdown signal from the scheduler, | ||
2966 | the service immediately tells the server to stop | ||
2967 | listening for incoming clients. Requests from normal existing clients are | ||
2968 | still processed and the server/service terminates once all normal clients | ||
2969 | have disconnected. Clients that are not expected to ever disconnect (such | ||
2970 | as clients that monitor performance values) can be marked as 'monitor' | ||
2971 | clients using GNUNET_SERVER_client_mark_monitor. Those clients will | ||
2972 | continue to be processed until all 'normal' clients have disconnected. | ||
2973 | Then, the server will terminate, closing the monitor connections. | ||
2974 | This mode is for example used by 'statistics', allowing existing 'normal' | ||
2975 | clients to set (possibly persistent) statistic values before terminating. | ||
2976 | |||
2977 | @end table | ||
2978 | |||
2979 | @c *********************************************************************** | ||
2980 | @node Optimizing Memory Consumption of GNUnet's (Multi-) Hash Maps | ||
2981 | @subsection Optimizing Memory Consumption of GNUnet's (Multi-) Hash Maps | ||
2982 | @c %**end of header | ||
2983 | |||
2984 | A commonly used data structure in GNUnet is a (multi-)hash map. It is most | ||
2985 | often used to map a peer identity to some data structure, but also to map | ||
2986 | arbitrary keys to values (for example to track requests in the distributed | ||
2987 | hash table or in file-sharing). As it is commonly used, the DHT is | ||
2988 | actually sometimes responsible for a large share of GNUnet's overall | ||
2989 | memory consumption (for some processes, 30% is not uncommon). The | ||
2990 | following text documents some API quirks (and their implications for | ||
2991 | applications) that were recently introduced to minimize the footprint of | ||
2992 | the hash map. | ||
2993 | |||
2994 | |||
2995 | @c *********************************************************************** | ||
2996 | @menu | ||
2997 | * Analysis:: | ||
2998 | * Solution:: | ||
2999 | * Migration:: | ||
3000 | * Conclusion:: | ||
3001 | * Availability:: | ||
3002 | @end menu | ||
3003 | |||
3004 | @node Analysis | ||
3005 | @subsubsection Analysis | ||
3006 | @c %**end of header | ||
3007 | |||
3008 | The main reason for the "excessive" memory consumption by the hash map is | ||
3009 | that GNUnet uses 512-bit cryptographic hash codes --- and the | ||
3010 | (multi-)hash map also uses the same 512-bit 'struct GNUNET_HashCode'. As | ||
3011 | a result, storing just the keys requires 64 bytes of memory for each key. | ||
3012 | As some applications like to keep a large number of entries in the hash | ||
3013 | map (after all, that's what maps are good for), 64 bytes per hash is | ||
3014 | significant: keeping a pointer to the value and having a linked list for | ||
3015 | collisions consume between 8 and 16 bytes, and 'malloc' may add about the | ||
3016 | same overhead per allocation, putting us in the 16 to 32 byte per entry | ||
3017 | ballpark. Adding a 64-byte key then triples the overall memory | ||
3018 | requirement for the hash map. | ||
3019 | |||
3020 | To make things "worse", most of the time storing the key in the hash map | ||
3021 | is not required: it is typically already in memory elsewhere! In most | ||
3022 | cases, the values stored in the hash map are some application-specific | ||
3023 | struct that _also_ contains the hash. Here is a simplified example: | ||
3024 | |||
3025 | @example | ||
3026 | struct MyValue @{ | ||
3027 | struct GNUNET_HashCode key; | ||
3028 | unsigned int my_data; @}; | ||
3029 | |||
3030 | // ... | ||
3031 | val = GNUNET_malloc (sizeof (struct MyValue)); | ||
3032 | val->key = key; | ||
3033 | val->my_data = 42; | ||
3034 | GNUNET_CONTAINER_multihashmap_put (map, &key, val, ...); | ||
3035 | @end example | ||
3036 | |||
3037 | This is a common pattern as later the entries might need to be removed, | ||
3038 | and at that time it is convenient to have the key immediately at hand: | ||
3039 | |||
3040 | @example | ||
3041 | GNUNET_CONTAINER_multihashmap_remove (map, &val->key, val); | ||
3042 | @end example | ||
3043 | |||
3044 | |||
3045 | Note that here we end up with two times 64 bytes for the key, plus maybe | ||
3046 | 64 bytes total for the rest of the 'struct MyValue' and the map entry in | ||
3047 | the hash map. The resulting redundant storage of the key increases | ||
3048 | overall memory consumption per entry from the "optimal" 128 bytes to 192 | ||
3049 | bytes. This is not just an extreme example: overheads in practice are | ||
3050 | actually sometimes close to those highlighted in this example. This is | ||
3051 | especially true for maps with a significant number of entries, as there | ||
3052 | we tend to really try to keep the entries small. | ||
3053 | |||
3054 | @c *********************************************************************** | ||
3055 | @node Solution | ||
3056 | @subsubsection Solution | ||
3057 | @c %**end of header | ||
3058 | |||
3059 | The solution that has now been implemented is to @strong{optionally} | ||
3060 | allow the hash map to not make a (deep) copy of the hash but instead have | ||
3061 | a pointer to the hash/key in the entry. This reduces the memory | ||
3062 | consumption for the key from 64 bytes to 4 to 8 bytes. However, it can | ||
3063 | also only work if the key is actually stored in the entry (which is the | ||
3064 | case most of the time) and if the entry does not modify the key (which in | ||
3065 | all of the code I'm aware of has been always the case if there key is | ||
3066 | stored in the entry). Finally, when the client stores an entry in the | ||
3067 | hash map, it @strong{must} provide a pointer to the key within the entry, | ||
3068 | not just a pointer to a transient location of the key. If | ||
3069 | the client code does not meet these requirements, the result is a dangling | ||
3070 | pointer and undefined behavior of the (multi-)hash map API. | ||
3071 | |||
3072 | @c *********************************************************************** | ||
3073 | @node Migration | ||
3074 | @subsubsection Migration | ||
3075 | @c %**end of header | ||
3076 | |||
3077 | To use the new feature, first check that the values contain the respective | ||
3078 | key (and never modify it). Then, all calls to | ||
3079 | @code{GNUNET_CONTAINER_multihashmap_put} on the respective map must be | ||
3080 | audited and most likely changed to pass a pointer into the value's struct. | ||
3081 | For the initial example, the new code would look like this: | ||
3082 | |||
3083 | @example | ||
3084 | struct MyValue @{ | ||
3085 | struct GNUNET_HashCode key; | ||
3086 | unsigned int my_data; @}; | ||
3087 | |||
3088 | // ... | ||
3089 | val = GNUNET_malloc (sizeof (struct MyValue)); | ||
3090 | val->key = key; val->my_data = 42; | ||
3091 | GNUNET_CONTAINER_multihashmap_put (map, &val->key, val, ...); | ||
3092 | @end example | ||
3093 | |||
3094 | |||
3095 | Note that @code{&val} was changed to @code{&val->key} in the argument to | ||
3096 | the @code{put} call. This is critical as often @code{key} is on the stack | ||
3097 | or in some other transient data structure and thus having the hash map | ||
3098 | keep a pointer to @code{key} would not work. Only the key inside of | ||
3099 | @code{val} has the same lifetime as the entry in the map (this must of | ||
3100 | course be checked as well). Naturally, @code{val->key} must be | ||
3101 | intiialized before the @code{put} call. Once all @code{put} calls have | ||
3102 | been converted and double-checked, you can change the call to create the | ||
3103 | hash map from | ||
3104 | |||
3105 | @example | ||
3106 | map = | ||
3107 | GNUNET_CONTAINER_multihashmap_create (SIZE, GNUNET_NO); | ||
3108 | @end example | ||
3109 | |||
3110 | to | ||
3111 | |||
3112 | @example | ||
3113 | map = GNUNET_CONTAINER_multihashmap_create (SIZE, GNUNET_YES); | ||
3114 | @end example | ||
3115 | |||
3116 | If everything was done correctly, you now use about 60 bytes less memory | ||
3117 | per entry in @code{map}. However, if now (or in the future) any call to | ||
3118 | @code{put} does not ensure that the given key is valid until the entry is | ||
3119 | removed from the map, undefined behavior is likely to be observed. | ||
3120 | |||
3121 | @c *********************************************************************** | ||
3122 | @node Conclusion | ||
3123 | @subsubsection Conclusion | ||
3124 | @c %**end of header | ||
3125 | |||
3126 | The new optimization can is often applicable and can result in a | ||
3127 | reduction in memory consumption of up to 30% in practice. However, it | ||
3128 | makes the code less robust as additional invariants are imposed on the | ||
3129 | multi hash map client. Thus applications should refrain from enabling the | ||
3130 | new mode unless the resulting performance increase is deemed significant | ||
3131 | enough. In particular, it should generally not be used in new code (wait | ||
3132 | at least until benchmarks exist). | ||
3133 | |||
3134 | @c *********************************************************************** | ||
3135 | @node Availability | ||
3136 | @subsubsection Availability | ||
3137 | @c %**end of header | ||
3138 | |||
3139 | The new multi hash map code was committed in SVN 24319 (will be in GNUnet | ||
3140 | 0.9.4). Various subsystems (transport, core, dht, file-sharing) were | ||
3141 | previously audited and modified to take advantage of the new capability. | ||
3142 | In particular, memory consumption of the file-sharing service is expected | ||
3143 | to drop by 20-30% due to this change. | ||
3144 | |||
3145 | |||
3146 | @cindex CONTAINER_MDLL API | ||
3147 | @node CONTAINER_MDLL API | ||
3148 | @subsection CONTAINER_MDLL API | ||
3149 | @c %**end of header | ||
3150 | |||
3151 | This text documents the GNUNET_CONTAINER_MDLL API. The | ||
3152 | GNUNET_CONTAINER_MDLL API is similar to the GNUNET_CONTAINER_DLL API in | ||
3153 | that it provides operations for the construction and manipulation of | ||
3154 | doubly-linked lists. The key difference to the (simpler) DLL-API is that | ||
3155 | the MDLL-version allows a single element (instance of a "struct") to be | ||
3156 | in multiple linked lists at the same time. | ||
3157 | |||
3158 | Like the DLL API, the MDLL API stores (most of) the data structures for | ||
3159 | the doubly-linked list with the respective elements; only the 'head' and | ||
3160 | 'tail' pointers are stored "elsewhere" --- and the application needs to | ||
3161 | provide the locations of head and tail to each of the calls in the | ||
3162 | MDLL API. The key difference for the MDLL API is that the "next" and | ||
3163 | "previous" pointers in the struct can no longer be simply called "next" | ||
3164 | and "prev" --- after all, the element may be in multiple doubly-linked | ||
3165 | lists, so we cannot just have one "next" and one "prev" pointer! | ||
3166 | |||
3167 | The solution is to have multiple fields that must have a name of the | ||
3168 | format "next_XX" and "prev_XX" where "XX" is the name of one of the | ||
3169 | doubly-linked lists. Here is a simple example: | ||
3170 | |||
3171 | @example | ||
3172 | struct MyMultiListElement @{ | ||
3173 | struct MyMultiListElement *next_ALIST; | ||
3174 | struct MyMultiListElement *prev_ALIST; | ||
3175 | struct MyMultiListElement *next_BLIST; | ||
3176 | struct MyMultiListElement *prev_BLIST; | ||
3177 | void | ||
3178 | *data; | ||
3179 | @}; | ||
3180 | @end example | ||
3181 | |||
3182 | |||
3183 | Note that by convention, we use all-uppercase letters for the list names. | ||
3184 | In addition, the program needs to have a location for the head and tail | ||
3185 | pointers for both lists, for example: | ||
3186 | |||
3187 | @example | ||
3188 | static struct MyMultiListElement *head_ALIST; | ||
3189 | static struct MyMultiListElement *tail_ALIST; | ||
3190 | static struct MyMultiListElement *head_BLIST; | ||
3191 | static struct MyMultiListElement *tail_BLIST; | ||
3192 | @end example | ||
3193 | |||
3194 | |||
3195 | Using the MDLL-macros, we can now insert an element into the ALIST: | ||
3196 | |||
3197 | @example | ||
3198 | GNUNET_CONTAINER_MDLL_insert (ALIST, head_ALIST, tail_ALIST, element); | ||
3199 | @end example | ||
3200 | |||
3201 | |||
3202 | Passing "ALIST" as the first argument to MDLL specifies which of the | ||
3203 | next/prev fields in the 'struct MyMultiListElement' should be used. The | ||
3204 | extra "ALIST" argument and the "_ALIST" in the names of the | ||
3205 | next/prev-members are the only differences between the MDDL and DLL-API. | ||
3206 | Like the DLL-API, the MDLL-API offers functions for inserting (at head, | ||
3207 | at tail, after a given element) and removing elements from the list. | ||
3208 | Iterating over the list should be done by directly accessing the | ||
3209 | "next_XX" and/or "prev_XX" members. | ||
3210 | |||
3211 | @cindex Automatic Restart Manager | ||
3212 | @cindex ARM | ||
3213 | @node Automatic Restart Manager (ARM) | ||
3214 | @section Automatic Restart Manager (ARM) | ||
3215 | @c %**end of header | ||
3216 | |||
3217 | GNUnet's Automated Restart Manager (ARM) is the GNUnet service responsible | ||
3218 | for system initialization and service babysitting. ARM starts and halts | ||
3219 | services, detects configuration changes and restarts services impacted by | ||
3220 | the changes as needed. It's also responsible for restarting services in | ||
3221 | case of crashes and is planned to incorporate automatic debugging for | ||
3222 | diagnosing service crashes providing developers insights about crash | ||
3223 | reasons. The purpose of this document is to give GNUnet developer an idea | ||
3224 | about how ARM works and how to interact with it. | ||
3225 | |||
3226 | @menu | ||
3227 | * Basic functionality:: | ||
3228 | * Key configuration options:: | ||
3229 | * ARM - Availability:: | ||
3230 | * Reliability:: | ||
3231 | @end menu | ||
3232 | |||
3233 | @c *********************************************************************** | ||
3234 | @node Basic functionality | ||
3235 | @subsection Basic functionality | ||
3236 | @c %**end of header | ||
3237 | |||
3238 | @itemize @bullet | ||
3239 | @item ARM source code can be found under "src/arm".@ Service processes are | ||
3240 | managed by the functions in "gnunet-service-arm.c" which is controlled | ||
3241 | with "gnunet-arm.c" (main function in that file is ARM's entry point). | ||
3242 | |||
3243 | @item The functions responsible for communicating with ARM , starting and | ||
3244 | stopping services -including ARM service itself- are provided by the | ||
3245 | ARM API "arm_api.c".@ Function: GNUNET_ARM_connect() returns to the caller | ||
3246 | an ARM handle after setting it to the caller's context (configuration and | ||
3247 | scheduler in use). This handle can be used afterwards by the caller to | ||
3248 | communicate with ARM. Functions GNUNET_ARM_start_service() and | ||
3249 | GNUNET_ARM_stop_service() are used for starting and stopping services | ||
3250 | respectively. | ||
3251 | |||
3252 | @item A typical example of using these basic ARM services can be found in | ||
3253 | file test_arm_api.c. The test case connects to ARM, starts it, then uses | ||
3254 | it to start a service "resolver", stops the "resolver" then stops "ARM". | ||
3255 | @end itemize | ||
3256 | |||
3257 | @c *********************************************************************** | ||
3258 | @node Key configuration options | ||
3259 | @subsection Key configuration options | ||
3260 | @c %**end of header | ||
3261 | |||
3262 | Configurations for ARM and services should be available in a .conf file | ||
3263 | (As an example, see test_arm_api_data.conf). When running ARM, the | ||
3264 | configuration file to use should be passed to the command: | ||
3265 | |||
3266 | @example | ||
3267 | $ gnunet-arm -s -c configuration_to_use.conf | ||
3268 | @end example | ||
3269 | |||
3270 | If no configuration is passed, the default configuration file will be used | ||
3271 | (see GNUNET_PREFIX/share/gnunet/defaults.conf which is created from | ||
3272 | contrib/defaults.conf).@ Each of the services is having a section starting | ||
3273 | by the service name between square brackets, for example: "[arm]". | ||
3274 | The following options configure how ARM configures or interacts with the | ||
3275 | various services: | ||
3276 | |||
3277 | @table @asis | ||
3278 | |||
3279 | @item PORT Port number on which the service is listening for incoming TCP | ||
3280 | connections. ARM will start the services should it notice a request at | ||
3281 | this port. | ||
3282 | |||
3283 | @item HOSTNAME Specifies on which host the service is deployed. Note | ||
3284 | that ARM can only start services that are running on the local system | ||
3285 | (but will not check that the hostname matches the local machine name). | ||
3286 | This option is used by the @code{gnunet_client_lib.h} implementation to | ||
3287 | determine which system to connect to. The default is "localhost". | ||
3288 | |||
3289 | @item BINARY The name of the service binary file. | ||
3290 | |||
3291 | @item OPTIONS To be passed to the service. | ||
3292 | |||
3293 | @item PREFIX A command to pre-pend to the actual command, for example, | ||
3294 | running a service with "valgrind" or "gdb" | ||
3295 | |||
3296 | @item DEBUG Run in debug mode (much verbosity). | ||
3297 | |||
3298 | @item AUTOSTART ARM will listen to UNIX domain socket and/or TCP port of | ||
3299 | the service and start the service on-demand. | ||
3300 | |||
3301 | @item FORCESTART ARM will always start this service when the peer | ||
3302 | is started. | ||
3303 | |||
3304 | @item ACCEPT_FROM IPv4 addresses the service accepts connections from. | ||
3305 | |||
3306 | @item ACCEPT_FROM6 IPv6 addresses the service accepts connections from. | ||
3307 | |||
3308 | @end table | ||
3309 | |||
3310 | |||
3311 | Options that impact the operation of ARM overall are in the "[arm]" | ||
3312 | section. ARM is a normal service and has (except for AUTOSTART) all of the | ||
3313 | options that other services do. In addition, ARM has the | ||
3314 | following options: | ||
3315 | |||
3316 | @table @asis | ||
3317 | |||
3318 | @item GLOBAL_PREFIX Command to be pre-pended to all services that are | ||
3319 | going to run. | ||
3320 | |||
3321 | @item GLOBAL_POSTFIX Global option that will be supplied to all the | ||
3322 | services that are going to run. | ||
3323 | |||
3324 | @end table | ||
3325 | |||
3326 | @c *********************************************************************** | ||
3327 | @node ARM - Availability | ||
3328 | @subsection ARM - Availability | ||
3329 | @c %**end of header | ||
3330 | |||
3331 | As mentioned before, one of the features provided by ARM is starting | ||
3332 | services on demand. Consider the example of one service "client" that | ||
3333 | wants to connect to another service a "server". The "client" will ask ARM | ||
3334 | to run the "server". ARM starts the "server". The "server" starts | ||
3335 | listening to incoming connections. The "client" will establish a | ||
3336 | connection with the "server". And then, they will start to communicate | ||
3337 | together.@ One problem with that scheme is that it's slow!@ | ||
3338 | The "client" service wants to communicate with the "server" service at | ||
3339 | once and is not willing wait for it to be started and listening to | ||
3340 | incoming connections before serving its request.@ One solution for that | ||
3341 | problem will be that ARM starts all services as default services. That | ||
3342 | solution will solve the problem, yet, it's not quite practical, for some | ||
3343 | services that are going to be started can never be used or are going to | ||
3344 | be used after a relatively long time.@ | ||
3345 | The approach followed by ARM to solve this problem is as follows: | ||
3346 | |||
3347 | @itemize @bullet | ||
3348 | |||
3349 | @item For each service having a PORT field in the configuration file and | ||
3350 | that is not one of the default services ( a service that accepts incoming | ||
3351 | connections from clients), ARM creates listening sockets for all addresses | ||
3352 | associated with that service. | ||
3353 | |||
3354 | @item The "client" will immediately establish a connection with | ||
3355 | the "server". | ||
3356 | |||
3357 | @item ARM --- pretending to be the "server" --- will listen on the | ||
3358 | respective port and notice the incoming connection from the "client" | ||
3359 | (but not accept it), instead | ||
3360 | |||
3361 | @item Once there is an incoming connection, ARM will start the "server", | ||
3362 | passing on the listen sockets (now, the service is started and can do its | ||
3363 | work). | ||
3364 | |||
3365 | @item Other client services now can directly connect directly to the | ||
3366 | "server". | ||
3367 | |||
3368 | @end itemize | ||
3369 | |||
3370 | @c *********************************************************************** | ||
3371 | @node Reliability | ||
3372 | @subsection Reliability | ||
3373 | |||
3374 | One of the features provided by ARM, is the automatic restart of crashed | ||
3375 | services.@ ARM needs to know which of the running services died. Function | ||
3376 | "gnunet-service-arm.c/maint_child_death()" is responsible for that. The | ||
3377 | function is scheduled to run upon receiving a SIGCHLD signal. The | ||
3378 | function, then, iterates ARM's list of services running and monitors | ||
3379 | which service has died (crashed). For all crashing services, ARM restarts | ||
3380 | them.@ | ||
3381 | Now, considering the case of a service having a serious problem causing it | ||
3382 | to crash each time it's started by ARM. If ARM keeps blindly restarting | ||
3383 | such a service, we are going to have the pattern: | ||
3384 | start-crash-restart-crash-restart-crash and so forth!! Which is of course | ||
3385 | not practical.@ | ||
3386 | For that reason, ARM schedules the service to be restarted after waiting | ||
3387 | for some delay that grows exponentially with each crash/restart of that | ||
3388 | service.@ To clarify the idea, considering the following example: | ||
3389 | |||
3390 | @itemize @bullet | ||
3391 | |||
3392 | @item Service S crashed. | ||
3393 | |||
3394 | @item ARM receives the SIGCHLD and inspects its list of services to find | ||
3395 | the dead one(s). | ||
3396 | |||
3397 | @item ARM finds S dead and schedules it for restarting after "backoff" | ||
3398 | time which is initially set to 1ms. ARM will double the backoff time | ||
3399 | correspondent to S (now backoff(S) = 2ms) | ||
3400 | |||
3401 | @item Because there is a severe problem with S, it crashed again. | ||
3402 | |||
3403 | @item Again ARM receives the SIGCHLD and detects that it's S again that's | ||
3404 | crashed. ARM schedules it for restarting but after its new backoff time | ||
3405 | (which became 2ms), and doubles its backoff time (now backoff(S) = 4). | ||
3406 | |||
3407 | @item and so on, until backoff(S) reaches a certain threshold | ||
3408 | (@code{EXPONENTIAL_BACKOFF_THRESHOLD} is set to half an hour), | ||
3409 | after reaching it, backoff(S) will remain half an hour, | ||
3410 | hence ARM won't be busy for a lot of time trying to restart a | ||
3411 | problematic service. | ||
3412 | @end itemize | ||
3413 | |||
3414 | @cindex TRANSPORT Subsystem | ||
3415 | @node TRANSPORT Subsystem | ||
3416 | @section TRANSPORT Subsystem | ||
3417 | @c %**end of header | ||
3418 | |||
3419 | This chapter documents how the GNUnet transport subsystem works. The | ||
3420 | GNUnet transport subsystem consists of three main components: the | ||
3421 | transport API (the interface used by the rest of the system to access the | ||
3422 | transport service), the transport service itself (most of the interesting | ||
3423 | functions, such as choosing transports, happens here) and the transport | ||
3424 | plugins. A transport plugin is a concrete implementation for how two | ||
3425 | GNUnet peers communicate; many plugins exist, for example for | ||
3426 | communication via TCP, UDP, HTTP, HTTPS and others. Finally, the | ||
3427 | transport subsystem uses supporting code, especially the NAT/UPnP | ||
3428 | library to help with tasks such as NAT traversal. | ||
3429 | |||
3430 | Key tasks of the transport service include: | ||
3431 | |||
3432 | @itemize @bullet | ||
3433 | |||
3434 | @item Create our HELLO message, notify clients and neighbours if our HELLO | ||
3435 | changes (using NAT library as necessary) | ||
3436 | |||
3437 | @item Validate HELLOs from other peers (send PING), allow other peers to | ||
3438 | validate our HELLO's addresses (send PONG) | ||
3439 | |||
3440 | @item Upon request, establish connections to other peers (using address | ||
3441 | selection from ATS subsystem) and maintain them (again using PINGs and | ||
3442 | PONGs) as long as desired | ||
3443 | |||
3444 | @item Accept incoming connections, give ATS service the opportunity to | ||
3445 | switch communication channels | ||
3446 | |||
3447 | @item Notify clients about peers that have connected to us or that have | ||
3448 | been disconnected from us | ||
3449 | |||
3450 | @item If a (stateful) connection goes down unexpectedly (without explicit | ||
3451 | DISCONNECT), quickly attempt to recover (without notifying clients) but do | ||
3452 | notify clients quickly if reconnecting fails | ||
3453 | |||
3454 | @item Send (payload) messages arriving from clients to other peers via | ||
3455 | transport plugins and receive messages from other peers, forwarding | ||
3456 | those to clients | ||
3457 | |||
3458 | @item Enforce inbound traffic limits (using flow-control if it is | ||
3459 | applicable); outbound traffic limits are enforced by CORE, not by us (!) | ||
3460 | |||
3461 | @item Enforce restrictions on P2P connection as specified by the blacklist | ||
3462 | configuration and blacklisting clients | ||
3463 | @end itemize | ||
3464 | |||
3465 | Note that the term "clients" in the list above really refers to the | ||
3466 | GNUnet-CORE service, as CORE is typically the only client of the | ||
3467 | transport service. | ||
3468 | |||
3469 | @menu | ||
3470 | * Address validation protocol:: | ||
3471 | @end menu | ||
3472 | |||
3473 | @node Address validation protocol | ||
3474 | @subsection Address validation protocol | ||
3475 | @c %**end of header | ||
3476 | |||
3477 | This section documents how the GNUnet transport service validates | ||
3478 | connections with other peers. It is a high-level description of the | ||
3479 | protocol necessary to understand the details of the implementation. It | ||
3480 | should be noted that when we talk about PING and PONG messages in this | ||
3481 | section, we refer to transport-level PING and PONG messages, which are | ||
3482 | different from core-level PING and PONG messages (both in implementation | ||
3483 | and function). | ||
3484 | |||
3485 | The goal of transport-level address validation is to minimize the chances | ||
3486 | of a successful man-in-the-middle attack against GNUnet peers on the | ||
3487 | transport level. Such an attack would not allow the adversary to decrypt | ||
3488 | the P2P transmissions, but a successful attacker could at least measure | ||
3489 | traffic volumes and latencies (raising the adversaries capablities by | ||
3490 | those of a global passive adversary in the worst case). The scenarios we | ||
3491 | are concerned about is an attacker, Mallory, giving a @code{HELLO} to | ||
3492 | Alice that claims to be for Bob, but contains Mallory's IP address | ||
3493 | instead of Bobs (for some transport). | ||
3494 | Mallory would then forward the traffic to Bob (by initiating a | ||
3495 | connection to Bob and claiming to be Alice). As a further | ||
3496 | complication, the scheme has to work even if say Alice is behind a NAT | ||
3497 | without traversal support and hence has no address of her own (and thus | ||
3498 | Alice must always initiate the connection to Bob). | ||
3499 | |||
3500 | An additional constraint is that @code{HELLO} messages do not contain a | ||
3501 | cryptographic signature since other peers must be able to edit | ||
3502 | (i.e. remove) addresses from the @code{HELLO} at any time (this was | ||
3503 | not true in GNUnet 0.8.x). A basic @strong{assumption} is that each peer | ||
3504 | knows the set of possible network addresses that it @strong{might} | ||
3505 | be reachable under (so for example, the external IP address of the | ||
3506 | NAT plus the LAN address(es) with the respective ports). | ||
3507 | |||
3508 | The solution is the following. If Alice wants to validate that a given | ||
3509 | address for Bob is valid (i.e. is actually established @strong{directly} | ||
3510 | with the intended target), she sends a PING message over that connection | ||
3511 | to Bob. Note that in this case, Alice initiated the connection so only | ||
3512 | Alice knows which address was used for sure (Alice may be behind NAT, so | ||
3513 | whatever address Bob sees may not be an address Alice knows she has). | ||
3514 | Bob checks that the address given in the @code{PING} is actually one | ||
3515 | of Bob's addresses (ie: does not belong to Mallory), and if it is, | ||
3516 | sends back a @code{PONG} (with a signature that says that Bob | ||
3517 | owns/uses the address from the @code{PING}). | ||
3518 | Alice checks the signature and is happy if it is valid and the address | ||
3519 | in the @code{PONG} is the address Alice used. | ||
3520 | This is similar to the 0.8.x protocol where the @code{HELLO} contained a | ||
3521 | signature from Bob for each address used by Bob. | ||
3522 | Here, the purpose code for the signature is | ||
3523 | @code{GNUNET_SIGNATURE_PURPOSE_TRANSPORT_PONG_OWN}. After this, Alice will | ||
3524 | remember Bob's address and consider the address valid for a while (12h in | ||
3525 | the current implementation). Note that after this exchange, Alice only | ||
3526 | considers Bob's address to be valid, the connection itself is not | ||
3527 | considered 'established'. In particular, Alice may have many addresses | ||
3528 | for Bob that Alice considers valid. | ||
3529 | |||
3530 | @c TODO: reference Footnotes so that I don't have to duplicate the | ||
3531 | @c footnotes or add them to an index at the end. Is this possible at | ||
3532 | @c all in Texinfo? | ||
3533 | The @code{PONG} message is protected with a nonce/challenge against replay | ||
3534 | attacks@footnote{@uref{http://en.wikipedia.org/wiki/Replay_attack, replay}} | ||
3535 | and uses an expiration time for the signature (but those are almost | ||
3536 | implementation details). | ||
3537 | |||
3538 | @cindex NAT library | ||
3539 | @node NAT library | ||
3540 | @section NAT library | ||
3541 | @c %**end of header | ||
3542 | |||
3543 | The goal of the GNUnet NAT library is to provide a general-purpose API for | ||
3544 | NAT traversal @strong{without} third-party support. So protocols that | ||
3545 | involve contacting a third peer to help establish a connection between | ||
3546 | two peers are outside of the scope of this API. That does not mean that | ||
3547 | GNUnet doesn't support involving a third peer (we can do this with the | ||
3548 | distance-vector transport or using application-level protocols), it just | ||
3549 | means that the NAT API is not concerned with this possibility. The API is | ||
3550 | written so that it will work for IPv6-NAT in the future as well as | ||
3551 | current IPv4-NAT. Furthermore, the NAT API is always used, even for peers | ||
3552 | that are not behind NAT --- in that case, the mapping provided is simply | ||
3553 | the identity. | ||
3554 | |||
3555 | NAT traversal is initiated by calling @code{GNUNET_NAT_register}. Given a | ||
3556 | set of addresses that the peer has locally bound to (TCP or UDP), the NAT | ||
3557 | library will return (via callback) a (possibly longer) list of addresses | ||
3558 | the peer @strong{might} be reachable under. Internally, depending on the | ||
3559 | configuration, the NAT library will try to punch a hole (using UPnP) or | ||
3560 | just "know" that the NAT was manually punched and generate the respective | ||
3561 | external IP address (the one that should be globally visible) based on | ||
3562 | the given information. | ||
3563 | |||
3564 | The NAT library also supports ICMP-based NAT traversal. Here, the other | ||
3565 | peer can request connection-reversal by this peer (in this special case, | ||
3566 | the peer is even allowed to configure a port number of zero). If the NAT | ||
3567 | library detects a connection-reversal request, it returns the respective | ||
3568 | target address to the client as well. It should be noted that | ||
3569 | connection-reversal is currently only intended for TCP, so other plugins | ||
3570 | @strong{must} pass @code{NULL} for the reversal callback. Naturally, the | ||
3571 | NAT library also supports requesting connection reversal from a remote | ||
3572 | peer (@code{GNUNET_NAT_run_client}). | ||
3573 | |||
3574 | Once initialized, the NAT handle can be used to test if a given address is | ||
3575 | possibly a valid address for this peer (@code{GNUNET_NAT_test_address}). | ||
3576 | This is used for validating our addresses when generating PONGs. | ||
3577 | |||
3578 | Finally, the NAT library contains an API to test if our NAT configuration | ||
3579 | is correct. Using @code{GNUNET_NAT_test_start} @strong{before} binding to | ||
3580 | the respective port, the NAT library can be used to test if the | ||
3581 | configuration works. The test function act as a local client, initialize | ||
3582 | the NAT traversal and then contact a @code{gnunet-nat-server} (running by | ||
3583 | default on @code{gnunet.org}) and ask for a connection to be established. | ||
3584 | This way, it is easy to test if the current NAT configuration is valid. | ||
3585 | |||
3586 | @node Distance-Vector plugin | ||
3587 | @section Distance-Vector plugin | ||
3588 | @c %**end of header | ||
3589 | |||
3590 | The Distance Vector (DV) transport is a transport mechanism that allows | ||
3591 | peers to act as relays for each other, thereby connecting peers that would | ||
3592 | otherwise be unable to connect. This gives a larger connection set to | ||
3593 | applications that may work better with more peers to choose from (for | ||
3594 | example, File Sharing and/or DHT). | ||
3595 | |||
3596 | The Distance Vector transport essentially has two functions. The first is | ||
3597 | "gossiping" connection information about more distant peers to directly | ||
3598 | connected peers. The second is taking messages intended for non-directly | ||
3599 | connected peers and encapsulating them in a DV wrapper that contains the | ||
3600 | required information for routing the message through forwarding peers. Via | ||
3601 | gossiping, optimal routes through the known DV neighborhood are discovered | ||
3602 | and utilized and the message encapsulation provides some benefits in | ||
3603 | addition to simply getting the message from the correct source to the | ||
3604 | proper destination. | ||
3605 | |||
3606 | The gossiping function of DV provides an up to date routing table of | ||
3607 | peers that are available up to some number of hops. We call this a | ||
3608 | fisheye view of the network (like a fish, nearby objects are known while | ||
3609 | more distant ones unknown). Gossip messages are sent only to directly | ||
3610 | connected peers, but they are sent about other knowns peers within the | ||
3611 | "fisheye distance". Whenever two peers connect, they immediately gossip | ||
3612 | to each other about their appropriate other neighbors. They also gossip | ||
3613 | about the newly connected peer to previously | ||
3614 | connected neighbors. In order to keep the routing tables up to date, | ||
3615 | disconnect notifications are propogated as gossip as well (because | ||
3616 | disconnects may not be sent/received, timeouts are also used remove | ||
3617 | stagnant routing table entries). | ||
3618 | |||
3619 | Routing of messages via DV is straightforward. When the DV transport is | ||
3620 | notified of a message destined for a non-direct neighbor, the appropriate | ||
3621 | forwarding peer is selected, and the base message is encapsulated in a DV | ||
3622 | message which contains information about the initial peer and the intended | ||
3623 | recipient. At each forwarding hop, the initial peer is validated (the | ||
3624 | forwarding peer ensures that it has the initial peer in its neighborhood, | ||
3625 | otherwise the message is dropped). Next the base message is | ||
3626 | re-encapsulated in a new DV message for the next hop in the forwarding | ||
3627 | chain (or delivered to the current peer, if it has arrived at the | ||
3628 | destination). | ||
3629 | |||
3630 | Assume a three peer network with peers Alice, Bob and Carol. Assume that | ||
3631 | |||
3632 | @example | ||
3633 | Alice <-> Bob and Bob <-> Carol | ||
3634 | @end example | ||
3635 | |||
3636 | @noindent | ||
3637 | are direct (e.g. over TCP or UDP transports) connections, but that | ||
3638 | Alice cannot directly connect to Carol. | ||
3639 | This may be the case due to NAT or firewall restrictions, or perhaps | ||
3640 | based on one of the peers respective configurations. If the Distance | ||
3641 | Vector transport is enabled on all three peers, it will automatically | ||
3642 | discover (from the gossip protocol) that Alice and Carol can connect via | ||
3643 | Bob and provide a "virtual" Alice <-> Carol connection. Routing between | ||
3644 | Alice and Carol happens as follows; Alice creates a message destined for | ||
3645 | Carol and notifies the DV transport about it. The DV transport at Alice | ||
3646 | looks up Carol in the routing table and finds that the message must be | ||
3647 | sent through Bob for Carol. The message is encapsulated setting Alice as | ||
3648 | the initiator and Carol as the destination and sent to Bob. Bob receives | ||
3649 | the messages, verifies that both Alice and Carol are known to Bob, and | ||
3650 | re-wraps the message in a new DV message for Carol. | ||
3651 | The DV transport at Carol receives this message, unwraps the original | ||
3652 | message, and delivers it to Carol as though it came directly from Alice. | ||
3653 | |||
3654 | @cindex SMTP plugin | ||
3655 | @node SMTP plugin | ||
3656 | @section SMTP plugin | ||
3657 | @c %**end of header | ||
3658 | |||
3659 | This section describes the new SMTP transport plugin for GNUnet as it | ||
3660 | exists in the 0.7.x and 0.8.x branch. SMTP support is currently not | ||
3661 | available in GNUnet 0.9.x. This page also describes the transport layer | ||
3662 | abstraction (as it existed in 0.7.x and 0.8.x) in more detail and gives | ||
3663 | some benchmarking results. The performance results presented are quite | ||
3664 | old and maybe outdated at this point. | ||
3665 | |||
3666 | @itemize @bullet | ||
3667 | @item Why use SMTP for a peer-to-peer transport? | ||
3668 | @item SMTPHow does it work? | ||
3669 | @item How do I configure my peer? | ||
3670 | @item How do I test if it works? | ||
3671 | @item How fast is it? | ||
3672 | @item Is there any additional documentation? | ||
3673 | @end itemize | ||
3674 | |||
3675 | |||
3676 | @menu | ||
3677 | * Why use SMTP for a peer-to-peer transport?:: | ||
3678 | * How does it work?:: | ||
3679 | * How do I configure my peer?:: | ||
3680 | * How do I test if it works?:: | ||
3681 | * How fast is it?:: | ||
3682 | @end menu | ||
3683 | |||
3684 | @node Why use SMTP for a peer-to-peer transport? | ||
3685 | @subsection Why use SMTP for a peer-to-peer transport? | ||
3686 | @c %**end of header | ||
3687 | |||
3688 | There are many reasons why one would not want to use SMTP: | ||
3689 | |||
3690 | @itemize @bullet | ||
3691 | @item SMTP is using more bandwidth than TCP, UDP or HTTP | ||
3692 | @item SMTP has a much higher latency. | ||
3693 | @item SMTP requires significantly more computation (encoding and decoding | ||
3694 | time) for the peers. | ||
3695 | @item SMTP is significantly more complicated to configure. | ||
3696 | @item SMTP may be abused by tricking GNUnet into sending mail to@ | ||
3697 | non-participating third parties. | ||
3698 | @end itemize | ||
3699 | |||
3700 | So why would anybody want to use SMTP? | ||
3701 | @itemize @bullet | ||
3702 | @item SMTP can be used to contact peers behind NAT boxes (in virtual | ||
3703 | private networks). | ||
3704 | @item SMTP can be used to circumvent policies that limit or prohibit | ||
3705 | peer-to-peer traffic by masking as "legitimate" traffic. | ||
3706 | @item SMTP uses E-mail addresses which are independent of a specific IP, | ||
3707 | which can be useful to address peers that use dynamic IP addresses. | ||
3708 | @item SMTP can be used to initiate a connection (e.g. initial address | ||
3709 | exchange) and peers can then negotiate the use of a more efficient | ||
3710 | protocol (e.g. TCP) for the actual communication. | ||
3711 | @end itemize | ||
3712 | |||
3713 | In summary, SMTP can for example be used to send a message to a peer | ||
3714 | behind a NAT box that has a dynamic IP to tell the peer to establish a | ||
3715 | TCP connection to a peer outside of the private network. Even an | ||
3716 | extraordinary overhead for this first message would be irrelevant in this | ||
3717 | type of situation. | ||
3718 | |||
3719 | @node How does it work? | ||
3720 | @subsection How does it work? | ||
3721 | @c %**end of header | ||
3722 | |||
3723 | When a GNUnet peer needs to send a message to another GNUnet peer that has | ||
3724 | advertised (only) an SMTP transport address, GNUnet base64-encodes the | ||
3725 | message and sends it in an E-mail to the advertised address. The | ||
3726 | advertisement contains a filter which is placed in the E-mail header, | ||
3727 | such that the receiving host can filter the tagged E-mails and forward it | ||
3728 | to the GNUnet peer process. The filter can be specified individually by | ||
3729 | each peer and be changed over time. This makes it impossible to censor | ||
3730 | GNUnet E-mail messages by searching for a generic filter. | ||
3731 | |||
3732 | @node How do I configure my peer? | ||
3733 | @subsection How do I configure my peer? | ||
3734 | @c %**end of header | ||
3735 | |||
3736 | First, you need to configure @code{procmail} to filter your inbound E-mail | ||
3737 | for GNUnet traffic. The GNUnet messages must be delivered into a pipe, for | ||
3738 | example @code{/tmp/gnunet.smtp}. You also need to define a filter that is | ||
3739 | used by @command{procmail} to detect GNUnet messages. You are free to | ||
3740 | choose whichever filter you like, but you should make sure that it does | ||
3741 | not occur in your other E-mail. In our example, we will use | ||
3742 | @code{X-mailer: GNUnet}. The @code{~/.procmailrc} configuration file then | ||
3743 | looks like this: | ||
3744 | |||
3745 | @example | ||
3746 | :0: | ||
3747 | * ^X-mailer: GNUnet | ||
3748 | /tmp/gnunet.smtp | ||
3749 | # where do you want your other e-mail delivered to | ||
3750 | # (default: /var/spool/mail/) | ||
3751 | :0: /var/spool/mail/ | ||
3752 | @end example | ||
3753 | |||
3754 | After adding this file, first make sure that your regular E-mail still | ||
3755 | works (e.g. by sending an E-mail to yourself). Then edit the GNUnet | ||
3756 | configuration. In the section @code{SMTP} you need to specify your E-mail | ||
3757 | address under @code{EMAIL}, your mail server (for outgoing mail) under | ||
3758 | @code{SERVER}, the filter (X-mailer: GNUnet in the example) under | ||
3759 | @code{FILTER} and the name of the pipe under @code{PIPE}.@ The completed | ||
3760 | section could then look like this: | ||
3761 | |||
3762 | @example | ||
3763 | EMAIL = me@@mail.gnu.org MTU = 65000 SERVER = mail.gnu.org:25 FILTER = | ||
3764 | "X-mailer: GNUnet" PIPE = /tmp/gnunet.smtp | ||
3765 | @end example | ||
3766 | |||
3767 | Finally, you need to add @code{smtp} to the list of @code{TRANSPORTS} in | ||
3768 | the @code{GNUNETD} section. GNUnet peers will use the E-mail address that | ||
3769 | you specified to contact your peer until the advertisement times out. | ||
3770 | Thus, if you are not sure if everything works properly or if you are not | ||
3771 | planning to be online for a long time, you may want to configure this | ||
3772 | timeout to be short, e.g. just one hour. For this, set | ||
3773 | @code{HELLOEXPIRES} to @code{1} in the @code{GNUNETD} section. | ||
3774 | |||
3775 | This should be it, but you may probably want to test it first. | ||
3776 | |||
3777 | @node How do I test if it works? | ||
3778 | @subsection How do I test if it works? | ||
3779 | @c %**end of header | ||
3780 | |||
3781 | Any transport can be subjected to some rudimentary tests using the | ||
3782 | @code{gnunet-transport-check} tool. The tool sends a message to the local | ||
3783 | node via the transport and checks that a valid message is received. While | ||
3784 | this test does not involve other peers and can not check if firewalls or | ||
3785 | other network obstacles prohibit proper operation, this is a great | ||
3786 | testcase for the SMTP transport since it tests pretty much nearly all of | ||
3787 | the functionality. | ||
3788 | |||
3789 | @code{gnunet-transport-check} should only be used without running | ||
3790 | @code{gnunetd} at the same time. By default, @code{gnunet-transport-check} | ||
3791 | tests all transports that are specified in the configuration file. But | ||
3792 | you can specifically test SMTP by giving the option | ||
3793 | @code{--transport=smtp}. | ||
3794 | |||
3795 | Note that this test always checks if a transport can receive and send. | ||
3796 | While you can configure most transports to only receive or only send | ||
3797 | messages, this test will only work if you have configured the transport | ||
3798 | to send and receive messages. | ||
3799 | |||
3800 | @node How fast is it? | ||
3801 | @subsection How fast is it? | ||
3802 | @c %**end of header | ||
3803 | |||
3804 | We have measured the performance of the UDP, TCP and SMTP transport layer | ||
3805 | directly and when used from an application using the GNUnet core. | ||
3806 | Measureing just the transport layer gives the better view of the actual | ||
3807 | overhead of the protocol, whereas evaluating the transport from the | ||
3808 | application puts the overhead into perspective from a practical point of | ||
3809 | view. | ||
3810 | |||
3811 | The loopback measurements of the SMTP transport were performed on three | ||
3812 | different machines spanning a range of modern SMTP configurations. We | ||
3813 | used a PIII-800 running RedHat 7.3 with the Purdue Computer Science | ||
3814 | configuration which includes filters for spam. We also used a Xenon 2 GHZ | ||
3815 | with a vanilla RedHat 8.0 sendmail configuration. Furthermore, we used | ||
3816 | qmail on a PIII-1000 running Sorcerer GNU Linux (SGL). The numbers for | ||
3817 | UDP and TCP are provided using the SGL configuration. The qmail benchmark | ||
3818 | uses qmail's internal filtering whereas the sendmail benchmarks relies on | ||
3819 | procmail to filter and deliver the mail. We used the transport layer to | ||
3820 | send a message of b bytes (excluding transport protocol headers) directly | ||
3821 | to the local machine. This way, network latency and packet loss on the | ||
3822 | wire have no impact on the timings. n messages were sent sequentially over | ||
3823 | the transport layer, sending message i+1 after the i-th message was | ||
3824 | received. All messages were sent over the same connection and the time to | ||
3825 | establish the connection was not taken into account since this overhead is | ||
3826 | miniscule in practice --- as long as a connection is used for a | ||
3827 | significant number of messages. | ||
3828 | |||
3829 | @multitable @columnfractions .20 .15 .15 .15 .15 .15 | ||
3830 | @headitem Transport @tab UDP @tab TCP @tab SMTP (Purdue sendmail) | ||
3831 | @tab SMTP (RH 8.0) @tab SMTP (SGL qmail) | ||
3832 | @item 11 bytes @tab 31 ms @tab 55 ms @tab 781 s @tab 77 s @tab 24 s | ||
3833 | @item 407 bytes @tab 37 ms @tab 62 ms @tab 789 s @tab 78 s @tab 25 s | ||
3834 | @item 1,221 bytes @tab 46 ms @tab 73 ms @tab 804 s @tab 78 s @tab 25 s | ||
3835 | @end multitable | ||
3836 | |||
3837 | The benchmarks show that UDP and TCP are, as expected, both significantly | ||
3838 | faster compared with any of the SMTP services. Among the SMTP | ||
3839 | implementations, there can be significant differences depending on the | ||
3840 | SMTP configuration. Filtering with an external tool like procmail that | ||
3841 | needs to re-parse its configuration for each mail can be very expensive. | ||
3842 | Applying spam filters can also significantly impact the performance of | ||
3843 | the underlying SMTP implementation. The microbenchmark shows that SMTP | ||
3844 | can be a viable solution for initiating peer-to-peer sessions: a couple of | ||
3845 | seconds to connect to a peer are probably not even going to be noticed by | ||
3846 | users. The next benchmark measures the possible throughput for a | ||
3847 | transport. Throughput can be measured by sending multiple messages in | ||
3848 | parallel and measuring packet loss. Note that not only UDP but also the | ||
3849 | TCP transport can actually loose messages since the TCP implementation | ||
3850 | drops messages if the @code{write} to the socket would block. While the | ||
3851 | SMTP protocol never drops messages itself, it is often so | ||
3852 | slow that only a fraction of the messages can be sent and received in the | ||
3853 | given time-bounds. For this benchmark we report the message loss after | ||
3854 | allowing t time for sending m messages. If messages were not sent (or | ||
3855 | received) after an overall timeout of t, they were considered lost. The | ||
3856 | benchmark was performed using two Xeon 2 GHZ machines running RedHat 8.0 | ||
3857 | with sendmail. The machines were connected with a direct 100 MBit ethernet | ||
3858 | connection.@ Figures udp1200, tcp1200 and smtp-MTUs show that the | ||
3859 | throughput for messages of size 1,200 octects is 2,343 kbps, 3,310 kbps | ||
3860 | and 6 kbps for UDP, TCP and SMTP respectively. The high per-message | ||
3861 | overhead of SMTP can be improved by increasing the MTU, for example, an | ||
3862 | MTU of 12,000 octets improves the throughput to 13 kbps as figure | ||
3863 | smtp-MTUs shows. Our research paper) has some more details on the | ||
3864 | benchmarking results. | ||
3865 | |||
3866 | @cindex Bluetooth plugin | ||
3867 | @node Bluetooth plugin | ||
3868 | @section Bluetooth plugin | ||
3869 | @c %**end of header | ||
3870 | |||
3871 | This page describes the new Bluetooth transport plugin for GNUnet. The | ||
3872 | plugin is still in the testing stage so don't expect it to work | ||
3873 | perfectly. If you have any questions or problems just post them here or | ||
3874 | ask on the IRC channel. | ||
3875 | |||
3876 | @itemize @bullet | ||
3877 | @item What do I need to use the Bluetooth plugin transport? | ||
3878 | @item BluetoothHow does it work? | ||
3879 | @item What possible errors should I be aware of? | ||
3880 | @item How do I configure my peer? | ||
3881 | @item How can I test it? | ||
3882 | @end itemize | ||
3883 | |||
3884 | @menu | ||
3885 | * What do I need to use the Bluetooth plugin transport?:: | ||
3886 | * How does it work2?:: | ||
3887 | * What possible errors should I be aware of?:: | ||
3888 | * How do I configure my peer2?:: | ||
3889 | * How can I test it?:: | ||
3890 | * The implementation of the Bluetooth transport plugin:: | ||
3891 | @end menu | ||
3892 | |||
3893 | @node What do I need to use the Bluetooth plugin transport? | ||
3894 | @subsection What do I need to use the Bluetooth plugin transport? | ||
3895 | @c %**end of header | ||
3896 | |||
3897 | If you are a GNU/Linux user and you want to use the Bluetooth | ||
3898 | transport plugin you should install the | ||
3899 | @command{BlueZ development libraries} (if they aren't already | ||
3900 | installed). | ||
3901 | For instructions about how to install the libraries you should | ||
3902 | check out the BlueZ site | ||
3903 | (@uref{http://www.bluez.org/, http://www.bluez.org}). If you don't know if | ||
3904 | you have the necesarry libraries, don't worry, just run the GNUnet | ||
3905 | configure script and you will be able to see a notification at the end | ||
3906 | which will warn you if you don't have the necessary libraries. | ||
3907 | |||
3908 | If you are a Windows user you should have installed the | ||
3909 | @emph{MinGW}/@emph{MSys2} with the latest updates (especially the | ||
3910 | @emph{ws2bth} header). If this is your first build of GNUnet on Windows | ||
3911 | you should check out the SBuild repository. It will semi-automatically | ||
3912 | assembles a @emph{MinGW}/@emph{MSys2} installation with a lot of extra | ||
3913 | packages which are needed for the GNUnet build. So this will ease your | ||
3914 | work!@ Finally you just have to be sure that you have the correct drivers | ||
3915 | for your Bluetooth device installed and that your device is on and in a | ||
3916 | discoverable mode. The Windows Bluetooth Stack supports only the RFCOMM | ||
3917 | protocol so we cannot turn on your device programatically! | ||
3918 | |||
3919 | @c FIXME: Change to unique title | ||
3920 | @node How does it work2? | ||
3921 | @subsection How does it work2? | ||
3922 | @c %**end of header | ||
3923 | |||
3924 | The Bluetooth transport plugin uses virtually the same code as the WLAN | ||
3925 | plugin and only the helper binary is different. The helper takes a single | ||
3926 | argument, which represents the interface name and is specified in the | ||
3927 | configuration file. Here are the basic steps that are followed by the | ||
3928 | helper binary used on GNU/Linux: | ||
3929 | |||
3930 | @itemize @bullet | ||
3931 | @item it verifies if the name corresponds to a Bluetooth interface name | ||
3932 | @item it verifies if the iterface is up (if it is not, it tries to bring | ||
3933 | it up) | ||
3934 | @item it tries to enable the page and inquiry scan in order to make the | ||
3935 | device discoverable and to accept incoming connection requests | ||
3936 | @emph{The above operations require root access so you should start the | ||
3937 | transport plugin with root privileges.} | ||
3938 | @item it finds an available port number and registers a SDP service which | ||
3939 | will be used to find out on which port number is the server listening on | ||
3940 | and switch the socket in listening mode | ||
3941 | @item it sends a HELLO message with its address | ||
3942 | @item finally it forwards traffic from the reading sockets to the STDOUT | ||
3943 | and from the STDIN to the writing socket | ||
3944 | @end itemize | ||
3945 | |||
3946 | Once in a while the device will make an inquiry scan to discover the | ||
3947 | nearby devices and it will send them randomly HELLO messages for peer | ||
3948 | discovery. | ||
3949 | |||
3950 | @node What possible errors should I be aware of? | ||
3951 | @subsection What possible errors should I be aware of? | ||
3952 | @c %**end of header | ||
3953 | |||
3954 | @emph{This section is dedicated for GNU/Linux users} | ||
3955 | |||
3956 | Well there are many ways in which things could go wrong but I will try to | ||
3957 | present some tools that you could use to debug and some scenarios. | ||
3958 | |||
3959 | @itemize @bullet | ||
3960 | |||
3961 | @item @code{bluetoothd -n -d} : use this command to enable logging in the | ||
3962 | foreground and to print the logging messages | ||
3963 | |||
3964 | @item @code{hciconfig}: can be used to configure the Bluetooth devices. | ||
3965 | If you run it without any arguments it will print information about the | ||
3966 | state of the interfaces. So if you receive an error that the device | ||
3967 | couldn't be brought up you should try to bring it manually and to see if | ||
3968 | it works (use @code{hciconfig -a hciX up}). If you can't and the | ||
3969 | Bluetooth address has the form 00:00:00:00:00:00 it means that there is | ||
3970 | something wrong with the D-Bus daemon or with the Bluetooth daemon. Use | ||
3971 | @code{bluetoothd} tool to see the logs | ||
3972 | |||
3973 | @item @code{sdptool} can be used to control and interogate SDP servers. | ||
3974 | If you encounter problems regarding the SDP server (like the SDP server is | ||
3975 | down) you should check out if the D-Bus daemon is running correctly and to | ||
3976 | see if the Bluetooth daemon started correctly(use @code{bluetoothd} tool). | ||
3977 | Also, sometimes the SDP service could work but somehow the device couldn't | ||
3978 | register his service. Use @code{sdptool browse [dev-address]} to see if | ||
3979 | the service is registered. There should be a service with the name of the | ||
3980 | interface and GNUnet as provider. | ||
3981 | |||
3982 | @item @code{hcitool} : another useful tool which can be used to configure | ||
3983 | the device and to send some particular commands to it. | ||
3984 | |||
3985 | @item @code{hcidump} : could be used for low level debugging | ||
3986 | @end itemize | ||
3987 | |||
3988 | @c FIXME: A more unique name | ||
3989 | @node How do I configure my peer2? | ||
3990 | @subsection How do I configure my peer2? | ||
3991 | @c %**end of header | ||
3992 | |||
3993 | On GNU/Linux, you just have to be sure that the interface name | ||
3994 | corresponds to the one that you want to use. | ||
3995 | Use the @code{hciconfig} tool to check that. | ||
3996 | By default it is set to hci0 but you can change it. | ||
3997 | |||
3998 | A basic configuration looks like this: | ||
3999 | |||
4000 | @example | ||
4001 | [transport-bluetooth] | ||
4002 | # Name of the interface (typically hciX) | ||
4003 | INTERFACE = hci0 | ||
4004 | # Real hardware, no testing | ||
4005 | TESTMODE = 0 TESTING_IGNORE_KEYS = ACCEPT_FROM; | ||
4006 | @end example | ||
4007 | |||
4008 | In order to use the Bluetooth transport plugin when the transport service | ||
4009 | is started, you must add the plugin name to the default transport service | ||
4010 | plugins list. For example: | ||
4011 | |||
4012 | @example | ||
4013 | [transport] ... PLUGINS = dns bluetooth ... | ||
4014 | @end example | ||
4015 | |||
4016 | If you want to use only the Bluetooth plugin set | ||
4017 | @emph{PLUGINS = bluetooth} | ||
4018 | |||
4019 | On Windows, you cannot specify which device to use. The only thing that | ||
4020 | you should do is to add @emph{bluetooth} on the plugins list of the | ||
4021 | transport service. | ||
4022 | |||
4023 | @node How can I test it? | ||
4024 | @subsection How can I test it? | ||
4025 | @c %**end of header | ||
4026 | |||
4027 | If you have two Bluetooth devices on the same machine and you are using | ||
4028 | GNU/Linux you must: | ||
4029 | |||
4030 | @itemize @bullet | ||
4031 | |||
4032 | @item create two different file configuration (one which will use the | ||
4033 | first interface (@emph{hci0}) and the other which will use the second | ||
4034 | interface (@emph{hci1})). Let's name them @emph{peer1.conf} and | ||
4035 | @emph{peer2.conf}. | ||
4036 | |||
4037 | @item run @emph{gnunet-peerinfo -c peerX.conf -s} in order to generate the | ||
4038 | peers private keys. The @strong{X} must be replace with 1 or 2. | ||
4039 | |||
4040 | @item run @emph{gnunet-arm -c peerX.conf -s -i=transport} in order to | ||
4041 | start the transport service. (Make sure that you have "bluetooth" on the | ||
4042 | transport plugins list if the Bluetooth transport service doesn't start.) | ||
4043 | |||
4044 | @item run @emph{gnunet-peerinfo -c peer1.conf -s} to get the first peer's | ||
4045 | ID. If you already know your peer ID (you saved it from the first | ||
4046 | command), this can be skipped. | ||
4047 | |||
4048 | @item run @emph{gnunet-transport -c peer2.conf -p=PEER1_ID -s} to start | ||
4049 | sending data for benchmarking to the other peer. | ||
4050 | |||
4051 | @end itemize | ||
4052 | |||
4053 | |||
4054 | This scenario will try to connect the second peer to the first one and | ||
4055 | then start sending data for benchmarking. | ||
4056 | |||
4057 | On Windows you cannot test the plugin functionality using two Bluetooth | ||
4058 | devices from the same machine because after you install the drivers there | ||
4059 | will occur some conflicts between the Bluetooth stacks. (At least that is | ||
4060 | what happend on my machine : I wasn't able to use the Bluesoleil stack and | ||
4061 | the WINDCOMM one in the same time). | ||
4062 | |||
4063 | If you have two different machines and your configuration files are good | ||
4064 | you can use the same scenario presented on the begining of this section. | ||
4065 | |||
4066 | Another way to test the plugin functionality is to create your own | ||
4067 | application which will use the GNUnet framework with the Bluetooth | ||
4068 | transport service. | ||
4069 | |||
4070 | @node The implementation of the Bluetooth transport plugin | ||
4071 | @subsection The implementation of the Bluetooth transport plugin | ||
4072 | @c %**end of header | ||
4073 | |||
4074 | This page describes the implementation of the Bluetooth transport plugin. | ||
4075 | |||
4076 | First I want to remind you that the Bluetooth transport plugin uses | ||
4077 | virtually the same code as the WLAN plugin and only the helper binary is | ||
4078 | different. Also the scope of the helper binary from the Bluetooth | ||
4079 | transport plugin is the same as the one used for the wlan transport | ||
4080 | plugin: it acceses the interface and then it forwards traffic in both | ||
4081 | directions between the Bluetooth interface and stdin/stdout of the | ||
4082 | process involved. | ||
4083 | |||
4084 | The Bluetooth plugin transport could be used both on GNU/Linux and Windows | ||
4085 | platforms. | ||
4086 | |||
4087 | @itemize @bullet | ||
4088 | @item Linux functionality | ||
4089 | @item Windows functionality | ||
4090 | @item Pending Features | ||
4091 | @end itemize | ||
4092 | |||
4093 | |||
4094 | |||
4095 | @menu | ||
4096 | * Linux functionality:: | ||
4097 | * THE INITIALIZATION:: | ||
4098 | * THE LOOP:: | ||
4099 | * Details about the broadcast implementation:: | ||
4100 | * Windows functionality:: | ||
4101 | * Pending features:: | ||
4102 | @end menu | ||
4103 | |||
4104 | @node Linux functionality | ||
4105 | @subsubsection Linux functionality | ||
4106 | @c %**end of header | ||
4107 | |||
4108 | In order to implement the plugin functionality on GNU/Linux I | ||
4109 | used the BlueZ stack. | ||
4110 | For the communication with the other devices I used the RFCOMM | ||
4111 | protocol. Also I used the HCI protocol to gain some control over the | ||
4112 | device. The helper binary takes a single argument (the name of the | ||
4113 | Bluetooth interface) and is separated in two stages: | ||
4114 | |||
4115 | @c %** 'THE INITIALIZATION' should be in bigger letters or stand out, not | ||
4116 | @c %** starting a new section? | ||
4117 | @node THE INITIALIZATION | ||
4118 | @subsubsection THE INITIALIZATION | ||
4119 | |||
4120 | @itemize @bullet | ||
4121 | @item first, it checks if we have root privilegies | ||
4122 | (@emph{Remember that we need to have root privilegies in order to be able | ||
4123 | to bring the interface up if it is down or to change its state.}). | ||
4124 | |||
4125 | @item second, it verifies if the interface with the given name exists. | ||
4126 | |||
4127 | @strong{If the interface with that name exists and it is a Bluetooth | ||
4128 | interface:} | ||
4129 | |||
4130 | @item it creates a RFCOMM socket which will be used for listening and call | ||
4131 | the @emph{open_device} method | ||
4132 | |||
4133 | On the @emph{open_device} method: | ||
4134 | @itemize @bullet | ||
4135 | @item creates a HCI socket used to send control events to the the device | ||
4136 | @item searches for the device ID using the interface name | ||
4137 | @item saves the device MAC address | ||
4138 | @item checks if the interface is down and tries to bring it UP | ||
4139 | @item checks if the interface is in discoverable mode and tries to make it | ||
4140 | discoverable | ||
4141 | @item closes the HCI socket and binds the RFCOMM one | ||
4142 | @item switches the RFCOMM socket in listening mode | ||
4143 | @item registers the SDP service (the service will be used by the other | ||
4144 | devices to get the port on which this device is listening on) | ||
4145 | @end itemize | ||
4146 | |||
4147 | @item drops the root privilegies | ||
4148 | |||
4149 | @strong{If the interface is not a Bluetooth interface the helper exits | ||
4150 | with a suitable error} | ||
4151 | @end itemize | ||
4152 | |||
4153 | @c %** Same as for @node entry above | ||
4154 | @node THE LOOP | ||
4155 | @subsubsection THE LOOP | ||
4156 | |||
4157 | The helper binary uses a list where it saves all the connected neighbour | ||
4158 | devices (@emph{neighbours.devices}) and two buffers (@emph{write_pout} and | ||
4159 | @emph{write_std}). The first message which is send is a control message | ||
4160 | with the device's MAC address in order to announce the peer presence to | ||
4161 | the neighbours. Here are a short description of what happens in the main | ||
4162 | loop: | ||
4163 | |||
4164 | @itemize @bullet | ||
4165 | @item Every time when it receives something from the STDIN it processes | ||
4166 | the data and saves the message in the first buffer (@emph{write_pout}). | ||
4167 | When it has something in the buffer, it gets the destination address from | ||
4168 | the buffer, searches the destination address in the list (if there is no | ||
4169 | connection with that device, it creates a new one and saves it to the | ||
4170 | list) and sends the message. | ||
4171 | @item Every time when it receives something on the listening socket it | ||
4172 | accepts the connection and saves the socket on a list with the reading | ||
4173 | sockets. @item Every time when it receives something from a reading | ||
4174 | socket it parses the message, verifies the CRC and saves it in the | ||
4175 | @emph{write_std} buffer in order to be sent later to the STDOUT. | ||
4176 | @end itemize | ||
4177 | |||
4178 | So in the main loop we use the select function to wait until one of the | ||
4179 | file descriptor saved in one of the two file descriptors sets used is | ||
4180 | ready to use. The first set (@emph{rfds}) represents the reading set and | ||
4181 | it could contain the list with the reading sockets, the STDIN file | ||
4182 | descriptor or the listening socket. The second set (@emph{wfds}) is the | ||
4183 | writing set and it could contain the sending socket or the STDOUT file | ||
4184 | descriptor. After the select function returns, we check which file | ||
4185 | descriptor is ready to use and we do what is supposed to do on that kind | ||
4186 | of event. @emph{For example:} if it is the listening socket then we | ||
4187 | accept a new connection and save the socket in the reading list; if it is | ||
4188 | the STDOUT file descriptor, then we write to STDOUT the message from the | ||
4189 | @emph{write_std} buffer. | ||
4190 | |||
4191 | To find out on which port a device is listening on we connect to the local | ||
4192 | SDP server and searche the registered service for that device. | ||
4193 | |||
4194 | @emph{You should be aware of the fact that if the device fails to connect | ||
4195 | to another one when trying to send a message it will attempt one more | ||
4196 | time. If it fails again, then it skips the message.} | ||
4197 | @emph{Also you should know that the transport Bluetooth plugin has | ||
4198 | support for @strong{broadcast messages}.} | ||
4199 | |||
4200 | @node Details about the broadcast implementation | ||
4201 | @subsubsection Details about the broadcast implementation | ||
4202 | @c %**end of header | ||
4203 | |||
4204 | First I want to point out that the broadcast functionality for the CONTROL | ||
4205 | messages is not implemented in a conventional way. Since the inquiry scan | ||
4206 | time is too big and it will take some time to send a message to all the | ||
4207 | discoverable devices I decided to tackle the problem in a different way. | ||
4208 | Here is how I did it: | ||
4209 | |||
4210 | @itemize @bullet | ||
4211 | @item If it is the first time when I have to broadcast a message I make an | ||
4212 | inquiry scan and save all the devices' addresses to a vector. | ||
4213 | @item After the inquiry scan ends I take the first address from the list | ||
4214 | and I try to connect to it. If it fails, I try to connect to the next one. | ||
4215 | If it succeeds, I save the socket to a list and send the message to the | ||
4216 | device. | ||
4217 | @item When I have to broadcast another message, first I search on the list | ||
4218 | for a new device which I'm not connected to. If there is no new device on | ||
4219 | the list I go to the beginning of the list and send the message to the | ||
4220 | old devices. After 5 cycles I make a new inquiry scan to check out if | ||
4221 | there are new discoverable devices and save them to the list. If there | ||
4222 | are no new discoverable devices I reset the cycling counter and go again | ||
4223 | through the old list and send messages to the devices saved in it. | ||
4224 | @end itemize | ||
4225 | |||
4226 | @strong{Therefore}: | ||
4227 | |||
4228 | @itemize @bullet | ||
4229 | @item every time when I have a broadcast message I look up on the list | ||
4230 | for a new device and send the message to it | ||
4231 | @item if I reached the end of the list for 5 times and I'm connected to | ||
4232 | all the devices from the list I make a new inquiry scan. | ||
4233 | @emph{The number of the list's cycles after an inquiry scan could be | ||
4234 | increased by redefining the MAX_LOOPS variable} | ||
4235 | @item when there are no new devices I send messages to the old ones. | ||
4236 | @end itemize | ||
4237 | |||
4238 | Doing so, the broadcast control messages will reach the devices but with | ||
4239 | delay. | ||
4240 | |||
4241 | @emph{NOTICE:} When I have to send a message to a certain device first I | ||
4242 | check on the broadcast list to see if we are connected to that device. If | ||
4243 | not we try to connect to it and in case of success we save the address and | ||
4244 | the socket on the list. If we are already connected to that device we | ||
4245 | simply use the socket. | ||
4246 | |||
4247 | @node Windows functionality | ||
4248 | @subsubsection Windows functionality | ||
4249 | @c %**end of header | ||
4250 | |||
4251 | For Windows I decided to use the Microsoft Bluetooth stack which has the | ||
4252 | advantage of coming standard from Windows XP SP2. The main disadvantage is | ||
4253 | that it only supports the RFCOMM protocol so we will not be able to have | ||
4254 | a low level control over the Bluetooth device. Therefore it is the user | ||
4255 | responsability to check if the device is up and in the discoverable mode. | ||
4256 | Also there are no tools which could be used for debugging in order to read | ||
4257 | the data coming from and going to a Bluetooth device, which obviously | ||
4258 | hindered my work. Another thing that slowed down the implementation of the | ||
4259 | plugin (besides that I wasn't too accomodated with the win32 API) was that | ||
4260 | there were some bugs on MinGW regarding the Bluetooth. Now they are solved | ||
4261 | but you should keep in mind that you should have the latest updates | ||
4262 | (especially the @emph{ws2bth} header). | ||
4263 | |||
4264 | Besides the fact that it uses the Windows Sockets, the Windows | ||
4265 | implemenation follows the same principles as the GNU/Linux one: | ||
4266 | |||
4267 | @itemize @bullet | ||
4268 | @item It has a initalization part where it initializes the | ||
4269 | Windows Sockets, creates a RFCOMM socket which will be binded and switched | ||
4270 | to the listening mode and registers a SDP service. In the Microsoft | ||
4271 | Bluetooth API there are two ways to work with the SDP: | ||
4272 | @itemize @bullet | ||
4273 | @item an easy way which works with very simple service records | ||
4274 | @item a hard way which is useful when you need to update or to delete the | ||
4275 | record | ||
4276 | @end itemize | ||
4277 | @end itemize | ||
4278 | |||
4279 | Since I only needed the SDP service to find out on which port the device | ||
4280 | is listening on and that did not change, I decided to use the easy way. | ||
4281 | In order to register the service I used the @emph{WSASetService} function | ||
4282 | and I generated the @emph{Universally Unique Identifier} with the | ||
4283 | @emph{guidgen.exe} Windows's tool. | ||
4284 | |||
4285 | In the loop section the only difference from the GNU/Linux implementation | ||
4286 | is that I used the @code{GNUNET_NETWORK} library for | ||
4287 | functions like @emph{accept}, @emph{bind}, @emph{connect} or | ||
4288 | @emph{select}. I decided to use the | ||
4289 | @code{GNUNET_NETWORK} library because I also needed to interact | ||
4290 | with the STDIN and STDOUT handles and on Windows | ||
4291 | the select function is only defined for sockets, | ||
4292 | and it will not work for arbitrary file handles. | ||
4293 | |||
4294 | Another difference between GNU/Linux and Windows implementation is that in | ||
4295 | GNU/Linux, the Bluetooth address is represented in 48 bits | ||
4296 | while in Windows is represented in 64 bits. | ||
4297 | Therefore I had to do some changes on @emph{plugin_transport_wlan} header. | ||
4298 | |||
4299 | Also, currently on Windows the Bluetooth plugin doesn't have support for | ||
4300 | broadcast messages. When it receives a broadcast message it will skip it. | ||
4301 | |||
4302 | @node Pending features | ||
4303 | @subsubsection Pending features | ||
4304 | @c %**end of header | ||
4305 | |||
4306 | @itemize @bullet | ||
4307 | @item Implement the broadcast functionality on Windows @emph{(currently | ||
4308 | working on)} | ||
4309 | @item Implement a testcase for the helper :@ @emph{The testcase | ||
4310 | consists of a program which emaluates the plugin and uses the helper. It | ||
4311 | will simulate connections, disconnections and data transfers.} | ||
4312 | @end itemize | ||
4313 | |||
4314 | If you have a new idea about a feature of the plugin or suggestions about | ||
4315 | how I could improve the implementation you are welcome to comment or to | ||
4316 | contact me. | ||
4317 | |||
4318 | @node WLAN plugin | ||
4319 | @section WLAN plugin | ||
4320 | @c %**end of header | ||
4321 | |||
4322 | This section documents how the wlan transport plugin works. Parts which | ||
4323 | are not implemented yet or could be better implemented are described at | ||
4324 | the end. | ||
4325 | |||
4326 | @cindex ATS Subsystem | ||
4327 | @node ATS Subsystem | ||
4328 | @section ATS Subsystem | ||
4329 | @c %**end of header | ||
4330 | |||
4331 | ATS stands for "automatic transport selection", and the function of ATS in | ||
4332 | GNUnet is to decide on which address (and thus transport plugin) should | ||
4333 | be used for two peers to communicate, and what bandwidth limits should be | ||
4334 | imposed on such an individual connection. To help ATS make an informed | ||
4335 | decision, higher-level services inform the ATS service about their | ||
4336 | requirements and the quality of the service rendered. The ATS service | ||
4337 | also interacts with the transport service to be appraised of working | ||
4338 | addresses and to communicate its resource allocation decisions. Finally, | ||
4339 | the ATS service's operation can be observed using a monitoring API. | ||
4340 | |||
4341 | The main logic of the ATS service only collects the available addresses, | ||
4342 | their performance characteristics and the applications requirements, but | ||
4343 | does not make the actual allocation decision. This last critical step is | ||
4344 | left to an ATS plugin, as we have implemented (currently three) different | ||
4345 | allocation strategies which differ significantly in their performance and | ||
4346 | maturity, and it is still unclear if any particular plugin is generally | ||
4347 | superior. | ||
4348 | |||
4349 | @cindex CORE Subsystem | ||
4350 | @node CORE Subsystem | ||
4351 | @section CORE Subsystem | ||
4352 | @c %**end of header | ||
4353 | |||
4354 | The CORE subsystem in GNUnet is responsible for securing link-layer | ||
4355 | communications between nodes in the GNUnet overlay network. CORE builds | ||
4356 | on the TRANSPORT subsystem which provides for the actual, insecure, | ||
4357 | unreliable link-layer communication (for example, via UDP or WLAN), and | ||
4358 | then adds fundamental security to the connections: | ||
4359 | |||
4360 | @itemize @bullet | ||
4361 | @item confidentiality with so-called perfect forward secrecy; we use | ||
4362 | ECDHE@footnote{@uref{http://en.wikipedia.org/wiki/Elliptic_curve_Diffie%E2%80%93Hellman, Elliptic-curve Diffie---Hellman}} | ||
4363 | powered by Curve25519 | ||
4364 | @footnote{@uref{http://cr.yp.to/ecdh.html, Curve25519}} for the key | ||
4365 | exchange and then use symmetric encryption, encrypting with both AES-256 | ||
4366 | @footnote{@uref{http://en.wikipedia.org/wiki/Rijndael, AES-256}} and | ||
4367 | Twofish @footnote{@uref{http://en.wikipedia.org/wiki/Twofish, Twofish}} | ||
4368 | @item @uref{http://en.wikipedia.org/wiki/Authentication, authentication} | ||
4369 | is achieved by signing the ephemeral keys using Ed25519 | ||
4370 | @footnote{@uref{http://ed25519.cr.yp.to/, Ed25519}}, a deterministic | ||
4371 | variant of ECDSA | ||
4372 | @footnote{@uref{http://en.wikipedia.org/wiki/ECDSA, ECDSA}} | ||
4373 | @item integrity protection (using SHA-512 | ||
4374 | @footnote{@uref{http://en.wikipedia.org/wiki/SHA-2, SHA-512}} to do | ||
4375 | encrypt-then-MAC | ||
4376 | @footnote{@uref{http://en.wikipedia.org/wiki/Authenticated_encryption, encrypt-then-MAC}}) | ||
4377 | @item Replay | ||
4378 | @footnote{@uref{http://en.wikipedia.org/wiki/Replay_attack, replay}} | ||
4379 | protection (using nonces, timestamps, challenge-response, | ||
4380 | message counters and ephemeral keys) | ||
4381 | @item liveness (keep-alive messages, timeout) | ||
4382 | @end itemize | ||
4383 | |||
4384 | @menu | ||
4385 | * Limitations:: | ||
4386 | * When is a peer "connected"?:: | ||
4387 | * libgnunetcore:: | ||
4388 | * The CORE Client-Service Protocol:: | ||
4389 | * The CORE Peer-to-Peer Protocol:: | ||
4390 | @end menu | ||
4391 | |||
4392 | @cindex core subsystem limitations | ||
4393 | @node Limitations | ||
4394 | @subsection Limitations | ||
4395 | @c %**end of header | ||
4396 | |||
4397 | CORE does not perform | ||
4398 | @uref{http://en.wikipedia.org/wiki/Routing, routing}; using CORE it is | ||
4399 | only possible to communicate with peers that happen to already be | ||
4400 | "directly" connected with each other. CORE also does not have an | ||
4401 | API to allow applications to establish such "direct" connections --- for | ||
4402 | this, applications can ask TRANSPORT, but TRANSPORT might not be able to | ||
4403 | establish a "direct" connection. The TOPOLOGY subsystem is responsible for | ||
4404 | trying to keep a few "direct" connections open at all times. Applications | ||
4405 | that need to talk to particular peers should use the CADET subsystem, as | ||
4406 | it can establish arbitrary "indirect" connections. | ||
4407 | |||
4408 | Because CORE does not perform routing, CORE must only be used directly by | ||
4409 | applications that either perform their own routing logic (such as | ||
4410 | anonymous file-sharing) or that do not require routing, for example | ||
4411 | because they are based on flooding the network. CORE communication is | ||
4412 | unreliable and delivery is possibly out-of-order. Applications that | ||
4413 | require reliable communication should use the CADET service. Each | ||
4414 | application can only queue one message per target peer with the CORE | ||
4415 | service at any time; messages cannot be larger than approximately | ||
4416 | 63 kilobytes. If messages are small, CORE may group multiple messages | ||
4417 | (possibly from different applications) prior to encryption. If permitted | ||
4418 | by the application (using the @uref{http://baus.net/on-tcp_cork/, cork} | ||
4419 | option), CORE may delay transmissions to facilitate grouping of multiple | ||
4420 | small messages. If cork is not enabled, CORE will transmit the message as | ||
4421 | soon as TRANSPORT allows it (TRANSPORT is responsible for limiting | ||
4422 | bandwidth and congestion control). CORE does not allow flow control; | ||
4423 | applications are expected to process messages at line-speed. If flow | ||
4424 | control is needed, applications should use the CADET service. | ||
4425 | |||
4426 | @cindex when is a peer connected | ||
4427 | @node When is a peer "connected"? | ||
4428 | @subsection When is a peer "connected"? | ||
4429 | @c %**end of header | ||
4430 | |||
4431 | In addition to the security features mentioned above, CORE also provides | ||
4432 | one additional key feature to applications using it, and that is a | ||
4433 | limited form of protocol-compatibility checking. CORE distinguishes | ||
4434 | between TRANSPORT-level connections (which enable communication with other | ||
4435 | peers) and application-level connections. Applications using the CORE API | ||
4436 | will (typically) learn about application-level connections from CORE, and | ||
4437 | not about TRANSPORT-level connections. When a typical application uses | ||
4438 | CORE, it will specify a set of message types | ||
4439 | (from @code{gnunet_protocols.h}) that it understands. CORE will then | ||
4440 | notify the application about connections it has with other peers if and | ||
4441 | only if those applications registered an intersecting set of message | ||
4442 | types with their CORE service. Thus, it is quite possible that CORE only | ||
4443 | exposes a subset of the established direct connections to a particular | ||
4444 | application --- and different applications running above CORE might see | ||
4445 | different sets of connections at the same time. | ||
4446 | |||
4447 | A special case are applications that do not register a handler for any | ||
4448 | message type. | ||
4449 | CORE assumes that these applications merely want to monitor connections | ||
4450 | (or "all" messages via other callbacks) and will notify those applications | ||
4451 | about all connections. This is used, for example, by the | ||
4452 | @code{gnunet-core} command-line tool to display the active connections. | ||
4453 | Note that it is also possible that the TRANSPORT service has more active | ||
4454 | connections than the CORE service, as the CORE service first has to | ||
4455 | perform a key exchange with connecting peers before exchanging information | ||
4456 | about supported message types and notifying applications about the new | ||
4457 | connection. | ||
4458 | |||
4459 | @cindex libgnunetcore | ||
4460 | @node libgnunetcore | ||
4461 | @subsection libgnunetcore | ||
4462 | @c %**end of header | ||
4463 | |||
4464 | The CORE API (defined in @file{gnunet_core_service.h}) is the basic | ||
4465 | messaging API used by P2P applications built using GNUnet. It provides | ||
4466 | applications the ability to send and receive encrypted messages to the | ||
4467 | peer's "directly" connected neighbours. | ||
4468 | |||
4469 | As CORE connections are generally "direct" connections,@ applications must | ||
4470 | not assume that they can connect to arbitrary peers this way, as "direct" | ||
4471 | connections may not always be possible. Applications using CORE are | ||
4472 | notified about which peers are connected. Creating new "direct" | ||
4473 | connections must be done using the TRANSPORT API. | ||
4474 | |||
4475 | The CORE API provides unreliable, out-of-order delivery. While the | ||
4476 | implementation tries to ensure timely, in-order delivery, both message | ||
4477 | losses and reordering are not detected and must be tolerated by the | ||
4478 | application. Most important, the core will NOT perform retransmission if | ||
4479 | messages could not be delivered. | ||
4480 | |||
4481 | Note that CORE allows applications to queue one message per connected | ||
4482 | peer. The rate at which each connection operates is influenced by the | ||
4483 | preferences expressed by local application as well as restrictions | ||
4484 | imposed by the other peer. Local applications can express their | ||
4485 | preferences for particular connections using the "performance" API of the | ||
4486 | ATS service. | ||
4487 | |||
4488 | Applications that require more sophisticated transmission capabilities | ||
4489 | such as TCP-like behavior, or if you intend to send messages to arbitrary | ||
4490 | remote peers, should use the CADET API. | ||
4491 | |||
4492 | The typical use of the CORE API is to connect to the CORE service using | ||
4493 | @code{GNUNET_CORE_connect}, process events from the CORE service (such as | ||
4494 | peers connecting, peers disconnecting and incoming messages) and send | ||
4495 | messages to connected peers using | ||
4496 | @code{GNUNET_CORE_notify_transmit_ready}. Note that applications must | ||
4497 | cancel pending transmission requests if they receive a disconnect event | ||
4498 | for a peer that had a transmission pending; furthermore, queueing more | ||
4499 | than one transmission request per peer per application using the | ||
4500 | service is not permitted. | ||
4501 | |||
4502 | The CORE API also allows applications to monitor all communications of the | ||
4503 | peer prior to encryption (for outgoing messages) or after decryption (for | ||
4504 | incoming messages). This can be useful for debugging, diagnostics or to | ||
4505 | establish the presence of cover traffic (for anonymity). As monitoring | ||
4506 | applications are often not interested in the payload, the monitoring | ||
4507 | callbacks can be configured to only provide the message headers (including | ||
4508 | the message type and size) instead of copying the full data stream to the | ||
4509 | monitoring client. | ||
4510 | |||
4511 | The init callback of the @code{GNUNET_CORE_connect} function is called | ||
4512 | with the hash of the public key of the peer. This public key is used to | ||
4513 | identify the peer globally in the GNUnet network. Applications are | ||
4514 | encouraged to check that the provided hash matches the hash that they are | ||
4515 | using (as theoretically the application may be using a different | ||
4516 | configuration file with a different private key, which would result in | ||
4517 | hard to find bugs). | ||
4518 | |||
4519 | As with most service APIs, the CORE API isolates applications from crashes | ||
4520 | of the CORE service. If the CORE service crashes, the application will see | ||
4521 | disconnect events for all existing connections. Once the connections are | ||
4522 | re-established, the applications will be receive matching connect events. | ||
4523 | |||
4524 | @cindex core clinet-service protocol | ||
4525 | @node The CORE Client-Service Protocol | ||
4526 | @subsection The CORE Client-Service Protocol | ||
4527 | @c %**end of header | ||
4528 | |||
4529 | This section describes the protocol between an application using the CORE | ||
4530 | service (the client) and the CORE service process itself. | ||
4531 | |||
4532 | |||
4533 | @menu | ||
4534 | * Setup2:: | ||
4535 | * Notifications:: | ||
4536 | * Sending:: | ||
4537 | @end menu | ||
4538 | |||
4539 | @node Setup2 | ||
4540 | @subsubsection Setup2 | ||
4541 | @c %**end of header | ||
4542 | |||
4543 | When a client connects to the CORE service, it first sends a | ||
4544 | @code{InitMessage} which specifies options for the connection and a set of | ||
4545 | message type values which are supported by the application. The options | ||
4546 | bitmask specifies which events the client would like to be notified about. | ||
4547 | The options include: | ||
4548 | |||
4549 | @table @asis | ||
4550 | @item GNUNET_CORE_OPTION_NOTHING No notifications | ||
4551 | @item GNUNET_CORE_OPTION_STATUS_CHANGE Peers connecting and disconnecting | ||
4552 | @item GNUNET_CORE_OPTION_FULL_INBOUND All inbound messages (after | ||
4553 | decryption) with full payload | ||
4554 | @item GNUNET_CORE_OPTION_HDR_INBOUND Just the @code{MessageHeader} | ||
4555 | of all inbound messages | ||
4556 | @item GNUNET_CORE_OPTION_FULL_OUTBOUND All outbound | ||
4557 | messages (prior to encryption) with full payload | ||
4558 | @item GNUNET_CORE_OPTION_HDR_OUTBOUND Just the @code{MessageHeader} of all | ||
4559 | outbound messages | ||
4560 | @end table | ||
4561 | |||
4562 | Typical applications will only monitor for connection status changes. | ||
4563 | |||
4564 | The CORE service responds to the @code{InitMessage} with an | ||
4565 | @code{InitReplyMessage} which contains the peer's identity. Afterwards, | ||
4566 | both CORE and the client can send messages. | ||
4567 | |||
4568 | @node Notifications | ||
4569 | @subsubsection Notifications | ||
4570 | @c %**end of header | ||
4571 | |||
4572 | The CORE will send @code{ConnectNotifyMessage}s and | ||
4573 | @code{DisconnectNotifyMessage}s whenever peers connect or disconnect from | ||
4574 | the CORE (assuming their type maps overlap with the message types | ||
4575 | registered by the client). When the CORE receives a message that matches | ||
4576 | the set of message types specified during the @code{InitMessage} (or if | ||
4577 | monitoring is enabled in for inbound messages in the options), it sends a | ||
4578 | @code{NotifyTrafficMessage} with the peer identity of the sender and the | ||
4579 | decrypted payload. The same message format (except with | ||
4580 | @code{GNUNET_MESSAGE_TYPE_CORE_NOTIFY_OUTBOUND} for the message type) is | ||
4581 | used to notify clients monitoring outbound messages; here, the peer | ||
4582 | identity given is that of the receiver. | ||
4583 | |||
4584 | @node Sending | ||
4585 | @subsubsection Sending | ||
4586 | @c %**end of header | ||
4587 | |||
4588 | When a client wants to transmit a message, it first requests a | ||
4589 | transmission slot by sending a @code{SendMessageRequest} which specifies | ||
4590 | the priority, deadline and size of the message. Note that these values | ||
4591 | may be ignored by CORE. When CORE is ready for the message, it answers | ||
4592 | with a @code{SendMessageReady} response. The client can then transmit the | ||
4593 | payload with a @code{SendMessage} message. Note that the actual message | ||
4594 | size in the @code{SendMessage} is allowed to be smaller than the size in | ||
4595 | the original request. A client may at any time send a fresh | ||
4596 | @code{SendMessageRequest}, which then superceeds the previous | ||
4597 | @code{SendMessageRequest}, which is then no longer valid. The client can | ||
4598 | tell which @code{SendMessageRequest} the CORE service's | ||
4599 | @code{SendMessageReady} message is for as all of these messages contain a | ||
4600 | "unique" request ID (based on a counter incremented by the client | ||
4601 | for each request). | ||
4602 | |||
4603 | @cindex CORE Peer-to-Peer Protocol | ||
4604 | @node The CORE Peer-to-Peer Protocol | ||
4605 | @subsection The CORE Peer-to-Peer Protocol | ||
4606 | @c %**end of header | ||
4607 | |||
4608 | |||
4609 | @menu | ||
4610 | * Creating the EphemeralKeyMessage:: | ||
4611 | * Establishing a connection:: | ||
4612 | * Encryption and Decryption:: | ||
4613 | * Type maps:: | ||
4614 | @end menu | ||
4615 | |||
4616 | @cindex EphemeralKeyMessage creation | ||
4617 | @node Creating the EphemeralKeyMessage | ||
4618 | @subsubsection Creating the EphemeralKeyMessage | ||
4619 | @c %**end of header | ||
4620 | |||
4621 | When the CORE service starts, each peer creates a fresh ephemeral (ECC) | ||
4622 | public-private key pair and signs the corresponding | ||
4623 | @code{EphemeralKeyMessage} with its long-term key (which we usually call | ||
4624 | the peer's identity; the hash of the public long term key is what results | ||
4625 | in a @code{struct GNUNET_PeerIdentity} in all GNUnet APIs. The ephemeral | ||
4626 | key is ONLY used for an ECDHE@footnote{@uref{http://en.wikipedia.org/wiki/Elliptic_curve_Diffie%E2%80%93Hellman, Elliptic-curve Diffie---Hellman}} | ||
4627 | exchange by the CORE service to establish symmetric session keys. A peer | ||
4628 | will use the same @code{EphemeralKeyMessage} for all peers for | ||
4629 | @code{REKEY_FREQUENCY}, which is usually 12 hours. After that time, it | ||
4630 | will create a fresh ephemeral key (forgetting the old one) and broadcast | ||
4631 | the new @code{EphemeralKeyMessage} to all connected peers, resulting in | ||
4632 | fresh symmetric session keys. Note that peers independently decide on | ||
4633 | when to discard ephemeral keys; it is not a protocol violation to discard | ||
4634 | keys more often. Ephemeral keys are also never stored to disk; restarting | ||
4635 | a peer will thus always create a fresh ephemeral key. The use of ephemeral | ||
4636 | keys is what provides @uref{http://en.wikipedia.org/wiki/Forward_secrecy, forward secrecy}. | ||
4637 | |||
4638 | Just before transmission, the @code{EphemeralKeyMessage} is patched to | ||
4639 | reflect the current sender_status, which specifies the current state of | ||
4640 | the connection from the point of view of the sender. The possible values | ||
4641 | are: | ||
4642 | |||
4643 | @itemize @bullet | ||
4644 | @item @code{KX_STATE_DOWN} Initial value, never used on the network | ||
4645 | @item @code{KX_STATE_KEY_SENT} We sent our ephemeral key, do not know the | ||
4646 | key of the other peer | ||
4647 | @item @code{KX_STATE_KEY_RECEIVED} This peer has received a valid | ||
4648 | ephemeral key of the other peer, but we are waiting for the other peer to | ||
4649 | confirm it's authenticity (ability to decode) via challenge-response. | ||
4650 | @item @code{KX_STATE_UP} The connection is fully up from the point of | ||
4651 | view of the sender (now performing keep-alives) | ||
4652 | @item @code{KX_STATE_REKEY_SENT} The sender has initiated a rekeying | ||
4653 | operation; the other peer has so far failed to confirm a working | ||
4654 | connection using the new ephemeral key | ||
4655 | @end itemize | ||
4656 | |||
4657 | @node Establishing a connection | ||
4658 | @subsubsection Establishing a connection | ||
4659 | @c %**end of header | ||
4660 | |||
4661 | Peers begin their interaction by sending a @code{EphemeralKeyMessage} to | ||
4662 | the other peer once the TRANSPORT service notifies the CORE service about | ||
4663 | the connection. | ||
4664 | A peer receiving an @code{EphemeralKeyMessage} with a status | ||
4665 | indicating that the sender does not have the receiver's ephemeral key, the | ||
4666 | receiver's @code{EphemeralKeyMessage} is sent in response. | ||
4667 | Additionally, if the receiver has not yet confirmed the authenticity of | ||
4668 | the sender, it also sends an (encrypted)@code{PingMessage} with a | ||
4669 | challenge (and the identity of the target) to the other peer. Peers | ||
4670 | receiving a @code{PingMessage} respond with an (encrypted) | ||
4671 | @code{PongMessage} which includes the challenge. Peers receiving a | ||
4672 | @code{PongMessage} check the challenge, and if it matches set the | ||
4673 | connection to @code{KX_STATE_UP}. | ||
4674 | |||
4675 | @node Encryption and Decryption | ||
4676 | @subsubsection Encryption and Decryption | ||
4677 | @c %**end of header | ||
4678 | |||
4679 | All functions related to the key exchange and encryption/decryption of | ||
4680 | messages can be found in @file{gnunet-service-core_kx.c} (except for the | ||
4681 | cryptographic primitives, which are in @file{util/crypto*.c}). | ||
4682 | Given the key material from ECDHE, a Key derivation function | ||
4683 | @footnote{@uref{https://en.wikipedia.org/wiki/Key_derivation_function, Key derivation function}} | ||
4684 | is used to derive two pairs of encryption and decryption keys for AES-256 | ||
4685 | and TwoFish, as well as initialization vectors and authentication keys | ||
4686 | (for HMAC@footnote{@uref{https://en.wikipedia.org/wiki/HMAC, HMAC}}). | ||
4687 | The HMAC is computed over the encrypted payload. | ||
4688 | Encrypted messages include an iv_seed and the HMAC in the header. | ||
4689 | |||
4690 | Each encrypted message in the CORE service includes a sequence number and | ||
4691 | a timestamp in the encrypted payload. The CORE service remembers the | ||
4692 | largest observed sequence number and a bit-mask which represents which of | ||
4693 | the previous 32 sequence numbers were already used. | ||
4694 | Messages with sequence numbers lower than the largest observed sequence | ||
4695 | number minus 32 are discarded. Messages with a timestamp that is less | ||
4696 | than @code{REKEY_TOLERANCE} off (5 minutes) are also discarded. This of | ||
4697 | course means that system clocks need to be reasonably synchronized for | ||
4698 | peers to be able to communicate. Additionally, as the ephemeral key | ||
4699 | changes every 12 hours, a peer would not even be able to decrypt messages | ||
4700 | older than 12 hours. | ||
4701 | |||
4702 | @node Type maps | ||
4703 | @subsubsection Type maps | ||
4704 | @c %**end of header | ||
4705 | |||
4706 | Once an encrypted connection has been established, peers begin to exchange | ||
4707 | type maps. Type maps are used to allow the CORE service to determine which | ||
4708 | (encrypted) connections should be shown to which applications. A type map | ||
4709 | is an array of 65536 bits representing the different types of messages | ||
4710 | understood by applications using the CORE service. Each CORE service | ||
4711 | maintains this map, simply by setting the respective bit for each message | ||
4712 | type supported by any of the applications using the CORE service. Note | ||
4713 | that bits for message types embedded in higher-level protocols (such as | ||
4714 | MESH) will not be included in these type maps. | ||
4715 | |||
4716 | Typically, the type map of a peer will be sparse. Thus, the CORE service | ||
4717 | attempts to compress its type map using @code{gzip}-style compression | ||
4718 | ("deflate") prior to transmission. However, if the compression fails to | ||
4719 | compact the map, the map may also be transmitted without compression | ||
4720 | (resulting in @code{GNUNET_MESSAGE_TYPE_CORE_COMPRESSED_TYPE_MAP} or | ||
4721 | @code{GNUNET_MESSAGE_TYPE_CORE_BINARY_TYPE_MAP} messages respectively). | ||
4722 | Upon receiving a type map, the respective CORE service notifies | ||
4723 | applications about the connection to the other peer if they support any | ||
4724 | message type indicated in the type map (or no message type at all). | ||
4725 | If the CORE service experience a connect or disconnect event from an | ||
4726 | application, it updates its type map (setting or unsetting the respective | ||
4727 | bits) and notifies its neighbours about the change. | ||
4728 | The CORE services of the neighbours then in turn generate connect and | ||
4729 | disconnect events for the peer that sent the type map for their respective | ||
4730 | applications. As CORE messages may be lost, the CORE service confirms | ||
4731 | receiving a type map by sending back a | ||
4732 | @code{GNUNET_MESSAGE_TYPE_CORE_CONFIRM_TYPE_MAP}. If such a confirmation | ||
4733 | (with the correct hash of the type map) is not received, the sender will | ||
4734 | retransmit the type map (with exponential back-off). | ||
4735 | |||
4736 | @cindex CADET Subsystem | ||
4737 | @node CADET Subsystem | ||
4738 | @section CADET Subsystem | ||
4739 | |||
4740 | The CADET subsystem in GNUnet is responsible for secure end-to-end | ||
4741 | communications between nodes in the GNUnet overlay network. CADET builds | ||
4742 | on the CORE subsystem which provides for the link-layer communication and | ||
4743 | then adds routing, forwarding and additional security to the connections. | ||
4744 | CADET offers the same cryptographic services as CORE, but on an | ||
4745 | end-to-end level. This is done so peers retransmitting traffic on behalf | ||
4746 | of other peers cannot access the payload data. | ||
4747 | |||
4748 | @itemize @bullet | ||
4749 | @item CADET provides confidentiality with so-called perfect forward | ||
4750 | secrecy; we use ECDHE powered by Curve25519 for the key exchange and then | ||
4751 | use symmetric encryption, encrypting with both AES-256 and Twofish | ||
4752 | @item authentication is achieved by signing the ephemeral keys using | ||
4753 | Ed25519, a deterministic variant of ECDSA | ||
4754 | @item integrity protection (using SHA-512 to do encrypt-then-MAC, although | ||
4755 | only 256 bits are sent to reduce overhead) | ||
4756 | @item replay protection (using nonces, timestamps, challenge-response, | ||
4757 | message counters and ephemeral keys) | ||
4758 | @item liveness (keep-alive messages, timeout) | ||
4759 | @end itemize | ||
4760 | |||
4761 | Additional to the CORE-like security benefits, CADET offers other | ||
4762 | properties that make it a more universal service than CORE. | ||
4763 | |||
4764 | @itemize @bullet | ||
4765 | @item CADET can establish channels to arbitrary peers in GNUnet. If a | ||
4766 | peer is not immediately reachable, CADET will find a path through the | ||
4767 | network and ask other peers to retransmit the traffic on its behalf. | ||
4768 | @item CADET offers (optional) reliability mechanisms. In a reliable | ||
4769 | channel traffic is guaranteed to arrive complete, unchanged and in-order. | ||
4770 | @item CADET takes care of flow and congestion control mechanisms, not | ||
4771 | allowing the sender to send more traffic than the receiver or the network | ||
4772 | are able to process. | ||
4773 | @end itemize | ||
4774 | |||
4775 | @menu | ||
4776 | * libgnunetcadet:: | ||
4777 | @end menu | ||
4778 | |||
4779 | @cindex libgnunetcadet | ||
4780 | @node libgnunetcadet | ||
4781 | @subsection libgnunetcadet | ||
4782 | |||
4783 | |||
4784 | The CADET API (defined in @file{gnunet_cadet_service.h}) is the | ||
4785 | messaging API used by P2P applications built using GNUnet. | ||
4786 | It provides applications the ability to send and receive encrypted | ||
4787 | messages to any peer participating in GNUnet. | ||
4788 | The API is heavily base on the CORE API. | ||
4789 | |||
4790 | CADET delivers messages to other peers in "channels". | ||
4791 | A channel is a permanent connection defined by a destination peer | ||
4792 | (identified by its public key) and a port number. | ||
4793 | Internally, CADET tunnels all channels towards a destiantion peer | ||
4794 | using one session key and relays the data on multiple "connections", | ||
4795 | independent from the channels. | ||
4796 | |||
4797 | Each channel has optional paramenters, the most important being the | ||
4798 | reliability flag. | ||
4799 | Should a message get lost on TRANSPORT/CORE level, if a channel is | ||
4800 | created with as reliable, CADET will retransmit the lost message and | ||
4801 | deliver it in order to the destination application. | ||
4802 | |||
4803 | To communicate with other peers using CADET, it is necessary to first | ||
4804 | connect to the service using @code{GNUNET_CADET_connect}. | ||
4805 | This function takes several parameters in form of callbacks, to allow the | ||
4806 | client to react to various events, like incoming channels or channels that | ||
4807 | terminate, as well as specify a list of ports the client wishes to listen | ||
4808 | to (at the moment it is not possible to start listening on further ports | ||
4809 | once connected, but nothing prevents a client to connect several times to | ||
4810 | CADET, even do one connection per listening port). | ||
4811 | The function returns a handle which has to be used for any further | ||
4812 | interaction with the service. | ||
4813 | |||
4814 | To connect to a remote peer a client has to call the | ||
4815 | @code{GNUNET_CADET_channel_create} function. The most important parameters | ||
4816 | given are the remote peer's identity (it public key) and a port, which | ||
4817 | specifies which application on the remote peer to connect to, similar to | ||
4818 | TCP/UDP ports. CADET will then find the peer in the GNUnet network and | ||
4819 | establish the proper low-level connections and do the necessary key | ||
4820 | exchanges to assure and authenticated, secure and verified communication. | ||
4821 | Similar to @code{GNUNET_CADET_connect},@code{GNUNET_CADET_create_channel} | ||
4822 | returns a handle to interact with the created channel. | ||
4823 | |||
4824 | For every message the client wants to send to the remote application, | ||
4825 | @code{GNUNET_CADET_notify_transmit_ready} must be called, indicating the | ||
4826 | channel on which the message should be sent and the size of the message | ||
4827 | (but not the message itself!). Once CADET is ready to send the message, | ||
4828 | the provided callback will fire, and the message contents are provided to | ||
4829 | this callback. | ||
4830 | |||
4831 | Please note the CADET does not provide an explicit notification of when a | ||
4832 | channel is connected. In loosely connected networks, like big wireless | ||
4833 | mesh networks, this can take several seconds, even minutes in the worst | ||
4834 | case. To be alerted when a channel is online, a client can call | ||
4835 | @code{GNUNET_CADET_notify_transmit_ready} immediately after | ||
4836 | @code{GNUNET_CADET_create_channel}. When the callback is activated, it | ||
4837 | means that the channel is online. The callback can give 0 bytes to CADET | ||
4838 | if no message is to be sent, this is ok. | ||
4839 | |||
4840 | If a transmission was requested but before the callback fires it is no | ||
4841 | longer needed, it can be cancelled with | ||
4842 | @code{GNUNET_CADET_notify_transmit_ready_cancel}, which uses the handle | ||
4843 | given back by @code{GNUNET_CADET_notify_transmit_ready}. | ||
4844 | As in the case of CORE, only one message can be requested at a time: a | ||
4845 | client must not call @code{GNUNET_CADET_notify_transmit_ready} again until | ||
4846 | the callback is called or the request is cancelled. | ||
4847 | |||
4848 | When a channel is no longer needed, a client can call | ||
4849 | @code{GNUNET_CADET_channel_destroy} to get rid of it. | ||
4850 | Note that CADET will try to transmit all pending traffic before notifying | ||
4851 | the remote peer of the destruction of the channel, including | ||
4852 | retransmitting lost messages if the channel was reliable. | ||
4853 | |||
4854 | Incoming channels, channels being closed by the remote peer, and traffic | ||
4855 | on any incoming or outgoing channels are given to the client when CADET | ||
4856 | executes the callbacks given to it at the time of | ||
4857 | @code{GNUNET_CADET_connect}. | ||
4858 | |||
4859 | Finally, when an application no longer wants to use CADET, it should call | ||
4860 | @code{GNUNET_CADET_disconnect}, but first all channels and pending | ||
4861 | transmissions must be closed (otherwise CADET will complain). | ||
4862 | |||
4863 | @cindex NSE Subsystem | ||
4864 | @node NSE Subsystem | ||
4865 | @section NSE Subsystem | ||
4866 | |||
4867 | |||
4868 | NSE stands for @dfn{Network Size Estimation}. The NSE subsystem provides | ||
4869 | other subsystems and users with a rough estimate of the number of peers | ||
4870 | currently participating in the GNUnet overlay. | ||
4871 | The computed value is not a precise number as producing a precise number | ||
4872 | in a decentralized, efficient and secure way is impossible. | ||
4873 | While NSE's estimate is inherently imprecise, NSE also gives the expected | ||
4874 | range. For a peer that has been running in a stable network for a | ||
4875 | while, the real network size will typically (99.7% of the time) be in the | ||
4876 | range of [2/3 estimate, 3/2 estimate]. We will now give an overview of the | ||
4877 | algorithm used to calculate the estimate; | ||
4878 | all of the details can be found in this technical report. | ||
4879 | |||
4880 | @c FIXME: link to the report. | ||
4881 | |||
4882 | @menu | ||
4883 | * Motivation:: | ||
4884 | * Principle:: | ||
4885 | * libgnunetnse:: | ||
4886 | * The NSE Client-Service Protocol:: | ||
4887 | * The NSE Peer-to-Peer Protocol:: | ||
4888 | @end menu | ||
4889 | |||
4890 | @node Motivation | ||
4891 | @subsection Motivation | ||
4892 | |||
4893 | |||
4894 | Some subsytems, like DHT, need to know the size of the GNUnet network to | ||
4895 | optimize some parameters of their own protocol. The decentralized nature | ||
4896 | of GNUnet makes efficient and securely counting the exact number of peers | ||
4897 | infeasable. Although there are several decentralized algorithms to count | ||
4898 | the number of peers in a system, so far there is none to do so securely. | ||
4899 | Other protocols may allow any malicious peer to manipulate the final | ||
4900 | result or to take advantage of the system to perform | ||
4901 | @dfn{Denial of Service} (DoS) attacks against the network. | ||
4902 | GNUnet's NSE protocol avoids these drawbacks. | ||
4903 | |||
4904 | |||
4905 | |||
4906 | @menu | ||
4907 | * Security:: | ||
4908 | @end menu | ||
4909 | |||
4910 | @cindex NSE security | ||
4911 | @cindex nse security | ||
4912 | @node Security | ||
4913 | @subsubsection Security | ||
4914 | |||
4915 | |||
4916 | The NSE subsystem is designed to be resilient against these attacks. | ||
4917 | It uses @uref{http://en.wikipedia.org/wiki/Proof-of-work_system, proofs of work} | ||
4918 | to prevent one peer from impersonating a large number of participants, | ||
4919 | which would otherwise allow an adversary to artifically inflate the | ||
4920 | estimate. | ||
4921 | The DoS protection comes from the time-based nature of the protocol: | ||
4922 | the estimates are calculated periodically and out-of-time traffic is | ||
4923 | either ignored or stored for later retransmission by benign peers. | ||
4924 | In particular, peers cannot trigger global network communication at will. | ||
4925 | |||
4926 | @cindex NSE principle | ||
4927 | @cindex nse principle | ||
4928 | @node Principle | ||
4929 | @subsection Principle | ||
4930 | |||
4931 | |||
4932 | The algorithm calculates the estimate by finding the globally closest | ||
4933 | peer ID to a random, time-based value. | ||
4934 | |||
4935 | The idea is that the closer the ID is to the random value, the more | ||
4936 | "densely packed" the ID space is, and therefore, more peers are in the | ||
4937 | network. | ||
4938 | |||
4939 | |||
4940 | |||
4941 | @menu | ||
4942 | * Example:: | ||
4943 | * Algorithm:: | ||
4944 | * Target value:: | ||
4945 | * Timing:: | ||
4946 | * Controlled Flooding:: | ||
4947 | * Calculating the estimate:: | ||
4948 | @end menu | ||
4949 | |||
4950 | @node Example | ||
4951 | @subsubsection Example | ||
4952 | |||
4953 | |||
4954 | Suppose all peers have IDs between 0 and 100 (our ID space), and the | ||
4955 | random value is 42. | ||
4956 | If the closest peer has the ID 70 we can imagine that the average | ||
4957 | "distance" between peers is around 30 and therefore the are around 3 | ||
4958 | peers in the whole ID space. On the other hand, if the closest peer has | ||
4959 | the ID 44, we can imagine that the space is rather packed with peers, | ||
4960 | maybe as much as 50 of them. | ||
4961 | Naturally, we could have been rather unlucky, and there is only one peer | ||
4962 | and happens to have the ID 44. Thus, the current estimate is calculated | ||
4963 | as the average over multiple rounds, and not just a single sample. | ||
4964 | |||
4965 | @node Algorithm | ||
4966 | @subsubsection Algorithm | ||
4967 | |||
4968 | |||
4969 | Given that example, one can imagine that the job of the subsystem is to | ||
4970 | efficiently communicate the ID of the closest peer to the target value | ||
4971 | to all the other peers, who will calculate the estimate from it. | ||
4972 | |||
4973 | @node Target value | ||
4974 | @subsubsection Target value | ||
4975 | |||
4976 | @c %**end of header | ||
4977 | |||
4978 | The target value itself is generated by hashing the current time, rounded | ||
4979 | down to an agreed value. If the rounding amount is 1h (default) and the | ||
4980 | time is 12:34:56, the time to hash would be 12:00:00. The process is | ||
4981 | repeated each rouning amount (in this example would be every hour). | ||
4982 | Every repetition is called a round. | ||
4983 | |||
4984 | @node Timing | ||
4985 | @subsubsection Timing | ||
4986 | @c %**end of header | ||
4987 | |||
4988 | The NSE subsystem has some timing control to avoid everybody broadcasting | ||
4989 | its ID all at one. Once each peer has the target random value, it | ||
4990 | compares its own ID to the target and calculates the hypothetical size of | ||
4991 | the network if that peer were to be the closest. | ||
4992 | Then it compares the hypothetical size with the estimate from the previous | ||
4993 | rounds. For each value there is an assiciated point in the period, | ||
4994 | let's call it "broadcast time". If its own hypothetical estimate | ||
4995 | is the same as the previous global estimate, its "broadcast time" will be | ||
4996 | in the middle of the round. If its bigger it will be earlier and if its | ||
4997 | smaller (the most likely case) it will be later. This ensures that the | ||
4998 | peers closests to the target value start broadcasting their ID the first. | ||
4999 | |||
5000 | @node Controlled Flooding | ||
5001 | @subsubsection Controlled Flooding | ||
5002 | |||
5003 | @c %**end of header | ||
5004 | |||
5005 | When a peer receives a value, first it verifies that it is closer than the | ||
5006 | closest value it had so far, otherwise it answers the incoming message | ||
5007 | with a message containing the better value. Then it checks a proof of | ||
5008 | work that must be included in the incoming message, to ensure that the | ||
5009 | other peer's ID is not made up (otherwise a malicious peer could claim to | ||
5010 | have an ID of exactly the target value every round). Once validated, it | ||
5011 | compares the brodcast time of the received value with the current time | ||
5012 | and if it's not too early, sends the received value to its neighbors. | ||
5013 | Otherwise it stores the value until the correct broadcast time comes. | ||
5014 | This prevents unnecessary traffic of sub-optimal values, since a better | ||
5015 | value can come before the broadcast time, rendering the previous one | ||
5016 | obsolete and saving the traffic that would have been used to broadcast it | ||
5017 | to the neighbors. | ||
5018 | |||
5019 | @node Calculating the estimate | ||
5020 | @subsubsection Calculating the estimate | ||
5021 | |||
5022 | @c %**end of header | ||
5023 | |||
5024 | Once the closest ID has been spread across the network each peer gets the | ||
5025 | exact distance betweed this ID and the target value of the round and | ||
5026 | calculates the estimate with a mathematical formula described in the tech | ||
5027 | report. The estimate generated with this method for a single round is not | ||
5028 | very precise. Remember the case of the example, where the only peer is the | ||
5029 | ID 44 and we happen to generate the target value 42, thinking there are | ||
5030 | 50 peers in the network. Therefore, the NSE subsystem remembers the last | ||
5031 | 64 estimates and calculates an average over them, giving a result of which | ||
5032 | usually has one bit of uncertainty (the real size could be half of the | ||
5033 | estimate or twice as much). Note that the actual network size is | ||
5034 | calculated in powers of two of the raw input, thus one bit of uncertainty | ||
5035 | means a factor of two in the size estimate. | ||
5036 | |||
5037 | @cindex libgnunetnse | ||
5038 | @node libgnunetnse | ||
5039 | @subsection libgnunetnse | ||
5040 | |||
5041 | @c %**end of header | ||
5042 | |||
5043 | The NSE subsystem has the simplest API of all services, with only two | ||
5044 | calls: @code{GNUNET_NSE_connect} and @code{GNUNET_NSE_disconnect}. | ||
5045 | |||
5046 | The connect call gets a callback function as a parameter and this function | ||
5047 | is called each time the network agrees on an estimate. This usually is | ||
5048 | once per round, with some exceptions: if the closest peer has a late | ||
5049 | local clock and starts spreading his ID after everyone else agreed on a | ||
5050 | value, the callback might be activated twice in a round, the second value | ||
5051 | being always bigger than the first. The default round time is set to | ||
5052 | 1 hour. | ||
5053 | |||
5054 | The disconnect call disconnects from the NSE subsystem and the callback | ||
5055 | is no longer called with new estimates. | ||
5056 | |||
5057 | |||
5058 | |||
5059 | @menu | ||
5060 | * Results:: | ||
5061 | * libgnunetnse - Examples:: | ||
5062 | @end menu | ||
5063 | |||
5064 | @node Results | ||
5065 | @subsubsection Results | ||
5066 | |||
5067 | @c %**end of header | ||
5068 | |||
5069 | The callback provides two values: the average and the | ||
5070 | @uref{http://en.wikipedia.org/wiki/Standard_deviation, standard deviation} | ||
5071 | of the last 64 rounds. The values provided by the callback function are | ||
5072 | logarithmic, this means that the real estimate numbers can be obtained by | ||
5073 | calculating 2 to the power of the given value (2average). From a | ||
5074 | statistics point of view this means that: | ||
5075 | |||
5076 | @itemize @bullet | ||
5077 | @item 68% of the time the real size is included in the interval | ||
5078 | [(2average-stddev), 2] | ||
5079 | @item 95% of the time the real size is included in the interval | ||
5080 | [(2average-2*stddev, 2^average+2*stddev] | ||
5081 | @item 99.7% of the time the real size is included in the interval | ||
5082 | [(2average-3*stddev, 2average+3*stddev] | ||
5083 | @end itemize | ||
5084 | |||
5085 | The expected standard variation for 64 rounds in a network of stable size | ||
5086 | is 0.2. Thus, we can say that normally: | ||
5087 | |||
5088 | @itemize @bullet | ||
5089 | @item 68% of the time the real size is in the range [-13%, +15%] | ||
5090 | @item 95% of the time the real size is in the range [-24%, +32%] | ||
5091 | @item 99.7% of the time the real size is in the range [-34%, +52%] | ||
5092 | @end itemize | ||
5093 | |||
5094 | As said in the introduction, we can be quite sure that usually the real | ||
5095 | size is between one third and three times the estimate. This can of | ||
5096 | course vary with network conditions. | ||
5097 | Thus, applications may want to also consider the provided standard | ||
5098 | deviation value, not only the average (in particular, if the standard | ||
5099 | veriation is very high, the average maybe meaningless: the network size is | ||
5100 | changing rapidly). | ||
5101 | |||
5102 | @node libgnunetnse - Examples | ||
5103 | @subsubsection libgnunetnse -Examples | ||
5104 | |||
5105 | @c %**end of header | ||
5106 | |||
5107 | Let's close with a couple examples. | ||
5108 | |||
5109 | @table @asis | ||
5110 | |||
5111 | @item Average: 10, std dev: 1 Here the estimate would be | ||
5112 | 2^10 = 1024 peers. @footnote{The range in which we can be 95% sure is: | ||
5113 | [2^8, 2^12] = [256, 4096]. We can be very (>99.7%) sure that the network | ||
5114 | is not a hundred peers and absolutely sure that it is not a million peers, | ||
5115 | but somewhere around a thousand.} | ||
5116 | |||
5117 | @item Average 22, std dev: 0.2 Here the estimate would be | ||
5118 | 2^22 = 4 Million peers. @footnote{The range in which we can be 99.7% sure | ||
5119 | is: [2^21.4, 2^22.6] = [2.8M, 6.3M]. We can be sure that the network size | ||
5120 | is around four million, with absolutely way of it being 1 million.} | ||
5121 | |||
5122 | @end table | ||
5123 | |||
5124 | To put this in perspective, if someone remembers the LHC Higgs boson | ||
5125 | results, were announced with "5 sigma" and "6 sigma" certainties. In this | ||
5126 | case a 5 sigma minimum would be 2 million and a 6 sigma minimum, | ||
5127 | 1.8 million. | ||
5128 | |||
5129 | @node The NSE Client-Service Protocol | ||
5130 | @subsection The NSE Client-Service Protocol | ||
5131 | |||
5132 | @c %**end of header | ||
5133 | |||
5134 | As with the API, the client-service protocol is very simple, only has 2 | ||
5135 | different messages, defined in @code{src/nse/nse.h}: | ||
5136 | |||
5137 | @itemize @bullet | ||
5138 | @item @code{GNUNET_MESSAGE_TYPE_NSE_START}@ This message has no parameters | ||
5139 | and is sent from the client to the service upon connection. | ||
5140 | @item @code{GNUNET_MESSAGE_TYPE_NSE_ESTIMATE}@ This message is sent from | ||
5141 | the service to the client for every new estimate and upon connection. | ||
5142 | Contains a timestamp for the estimate, the average and the standard | ||
5143 | deviation for the respective round. | ||
5144 | @end itemize | ||
5145 | |||
5146 | When the @code{GNUNET_NSE_disconnect} API call is executed, the client | ||
5147 | simply disconnects from the service, with no message involved. | ||
5148 | |||
5149 | @cindex NSE Peer-to-Peer Protocol | ||
5150 | @node The NSE Peer-to-Peer Protocol | ||
5151 | @subsection The NSE Peer-to-Peer Protocol | ||
5152 | |||
5153 | @c %**end of header | ||
5154 | |||
5155 | The NSE subsystem only has one message in the P2P protocol, the | ||
5156 | @code{GNUNET_MESSAGE_TYPE_NSE_P2P_FLOOD} message. | ||
5157 | |||
5158 | This message key contents are the timestamp to identify the round | ||
5159 | (differences in system clocks may cause some peers to send messages way | ||
5160 | too early or way too late, so the timestamp allows other peers to | ||
5161 | identify such messages easily), the | ||
5162 | @uref{http://en.wikipedia.org/wiki/Proof-of-work_system, proof of work} | ||
5163 | used to make it difficult to mount a | ||
5164 | @uref{http://en.wikipedia.org/wiki/Sybil_attack, Sybil attack}, and the | ||
5165 | public key, which is used to verify the signature on the message. | ||
5166 | |||
5167 | Every peer stores a message for the previous, current and next round. The | ||
5168 | messages for the previous and current round are given to peers that | ||
5169 | connect to us. The message for the next round is simply stored until our | ||
5170 | system clock advances to the next round. The message for the current round | ||
5171 | is what we are flooding the network with right now. | ||
5172 | At the beginning of each round the peer does the following: | ||
5173 | |||
5174 | @itemize @bullet | ||
5175 | @item calculates his own distance to the target value | ||
5176 | @item creates, signs and stores the message for the current round (unless | ||
5177 | it has a better message in the "next round" slot which came early in the | ||
5178 | previous round) | ||
5179 | @item calculates, based on the stored round message (own or received) when | ||
5180 | to stard flooding it to its neighbors | ||
5181 | @end itemize | ||
5182 | |||
5183 | Upon receiving a message the peer checks the validity of the message | ||
5184 | (round, proof of work, signature). The next action depends on the | ||
5185 | contents of the incoming message: | ||
5186 | |||
5187 | @itemize @bullet | ||
5188 | @item if the message is worse than the current stored message, the peer | ||
5189 | sends the current message back immediately, to stop the other peer from | ||
5190 | spreading suboptimal results | ||
5191 | @item if the message is better than the current stored message, the peer | ||
5192 | stores the new message and calculates the new target time to start | ||
5193 | spreading it to its neighbors (excluding the one the message came from) | ||
5194 | @item if the message is for the previous round, it is compared to the | ||
5195 | message stored in the "previous round slot", which may then be updated | ||
5196 | @item if the message is for the next round, it is compared to the message | ||
5197 | stored in the "next round slot", which again may then be updated | ||
5198 | @end itemize | ||
5199 | |||
5200 | Finally, when it comes to send the stored message for the current round to | ||
5201 | the neighbors there is a random delay added for each neighbor, to avoid | ||
5202 | traffic spikes and minimize cross-messages. | ||
5203 | |||
5204 | @cindex HOSTLIST Subsystem | ||
5205 | @node HOSTLIST Subsystem | ||
5206 | @section HOSTLIST Subsystem | ||
5207 | |||
5208 | @c %**end of header | ||
5209 | |||
5210 | Peers in the GNUnet overlay network need address information so that they | ||
5211 | can connect with other peers. GNUnet uses so called HELLO messages to | ||
5212 | store and exchange peer addresses. | ||
5213 | GNUnet provides several methods for peers to obtain this information: | ||
5214 | |||
5215 | @itemize @bullet | ||
5216 | @item out-of-band exchange of HELLO messages (manually, using for example | ||
5217 | gnunet-peerinfo) | ||
5218 | @item HELLO messages shipped with GNUnet (automatic with distribution) | ||
5219 | @item UDP neighbor discovery in LAN (IPv4 broadcast, IPv6 multicast) | ||
5220 | @item topology gossiping (learning from other peers we already connected | ||
5221 | to), and | ||
5222 | @item the HOSTLIST daemon covered in this section, which is particularly | ||
5223 | relevant for bootstrapping new peers. | ||
5224 | @end itemize | ||
5225 | |||
5226 | New peers have no existing connections (and thus cannot learn from gossip | ||
5227 | among peers), may not have other peers in their LAN and might be started | ||
5228 | with an outdated set of HELLO messages from the distribution. | ||
5229 | In this case, getting new peers to connect to the network requires either | ||
5230 | manual effort or the use of a HOSTLIST to obtain HELLOs. | ||
5231 | |||
5232 | @menu | ||
5233 | * HELLOs:: | ||
5234 | * Overview for the HOSTLIST subsystem:: | ||
5235 | * Interacting with the HOSTLIST daemon:: | ||
5236 | * Hostlist security address validation:: | ||
5237 | * The HOSTLIST daemon:: | ||
5238 | * The HOSTLIST server:: | ||
5239 | * The HOSTLIST client:: | ||
5240 | * Usage:: | ||
5241 | @end menu | ||
5242 | |||
5243 | @node HELLOs | ||
5244 | @subsection HELLOs | ||
5245 | |||
5246 | @c %**end of header | ||
5247 | |||
5248 | The basic information peers require to connect to other peers are | ||
5249 | contained in so called HELLO messages you can think of as a business card. | ||
5250 | Besides the identity of the peer (based on the cryptographic public key) a | ||
5251 | HELLO message may contain address information that specifies ways to | ||
5252 | contact a peer. By obtaining HELLO messages, a peer can learn how to | ||
5253 | contact other peers. | ||
5254 | |||
5255 | @node Overview for the HOSTLIST subsystem | ||
5256 | @subsection Overview for the HOSTLIST subsystem | ||
5257 | |||
5258 | @c %**end of header | ||
5259 | |||
5260 | The HOSTLIST subsystem provides a way to distribute and obtain contact | ||
5261 | information to connect to other peers using a simple HTTP GET request. | ||
5262 | It's implementation is split in three parts, the main file for the daemon | ||
5263 | itself (@file{gnunet-daemon-hostlist.c}), the HTTP client used to download | ||
5264 | peer information (@file{hostlist-client.c}) and the server component used | ||
5265 | to provide this information to other peers (@file{hostlist-server.c}). | ||
5266 | The server is basically a small HTTP web server (based on GNU | ||
5267 | libmicrohttpd) which provides a list of HELLOs known to the local peer for | ||
5268 | download. The client component is basically a HTTP client | ||
5269 | (based on libcurl) which can download hostlists from one or more websites. | ||
5270 | The hostlist format is a binary blob containing a sequence of HELLO | ||
5271 | messages. Note that any HTTP server can theoretically serve a hostlist, | ||
5272 | the build-in hostlist server makes it simply convenient to offer this | ||
5273 | service. | ||
5274 | |||
5275 | |||
5276 | @menu | ||
5277 | * Features:: | ||
5278 | * HOSTLIST - Limitations:: | ||
5279 | @end menu | ||
5280 | |||
5281 | @node Features | ||
5282 | @subsubsection Features | ||
5283 | |||
5284 | @c %**end of header | ||
5285 | |||
5286 | The HOSTLIST daemon can: | ||
5287 | |||
5288 | @itemize @bullet | ||
5289 | @item provide HELLO messages with validated addresses obtained from | ||
5290 | PEERINFO to download for other peers | ||
5291 | @item download HELLO messages and forward these message to the TRANSPORT | ||
5292 | subsystem for validation | ||
5293 | @item advertises the URL of this peer's hostlist address to other peers | ||
5294 | via gossip | ||
5295 | @item automatically learn about hostlist servers from the gossip of other | ||
5296 | peers | ||
5297 | @end itemize | ||
5298 | |||
5299 | @node HOSTLIST - Limitations | ||
5300 | @subsubsection HOSTLIST - Limitations | ||
5301 | |||
5302 | @c %**end of header | ||
5303 | |||
5304 | The HOSTLIST daemon does not: | ||
5305 | |||
5306 | @itemize @bullet | ||
5307 | @item verify the cryptographic information in the HELLO messages | ||
5308 | @item verify the address information in the HELLO messages | ||
5309 | @end itemize | ||
5310 | |||
5311 | @node Interacting with the HOSTLIST daemon | ||
5312 | @subsection Interacting with the HOSTLIST daemon | ||
5313 | |||
5314 | @c %**end of header | ||
5315 | |||
5316 | The HOSTLIST subsystem is currently implemented as a daemon, so there is | ||
5317 | no need for the user to interact with it and therefore there is no | ||
5318 | command line tool and no API to communicate with the daemon. In the | ||
5319 | future, we can envision changing this to allow users to manually trigger | ||
5320 | the download of a hostlist. | ||
5321 | |||
5322 | Since there is no command line interface to interact with HOSTLIST, the | ||
5323 | only way to interact with the hostlist is to use STATISTICS to obtain or | ||
5324 | modify information about the status of HOSTLIST: | ||
5325 | |||
5326 | @example | ||
5327 | $ gnunet-statistics -s hostlist | ||
5328 | @end example | ||
5329 | |||
5330 | @noindent | ||
5331 | In particular, HOSTLIST includes a @strong{persistent} value in statistics | ||
5332 | that specifies when the hostlist server might be queried next. As this | ||
5333 | value is exponentially increasing during runtime, developers may want to | ||
5334 | reset or manually adjust it. Note that HOSTLIST (but not STATISTICS) needs | ||
5335 | to be shutdown if changes to this value are to have any effect on the | ||
5336 | daemon (as HOSTLIST does not monitor STATISTICS for changes to the | ||
5337 | download frequency). | ||
5338 | |||
5339 | @node Hostlist security address validation | ||
5340 | @subsection Hostlist security address validation | ||
5341 | |||
5342 | @c %**end of header | ||
5343 | |||
5344 | Since information obtained from other parties cannot be trusted without | ||
5345 | validation, we have to distinguish between @emph{validated} and | ||
5346 | @emph{not validated} addresses. Before using (and so trusting) | ||
5347 | information from other parties, this information has to be double-checked | ||
5348 | (validated). Address validation is not done by HOSTLIST but by the | ||
5349 | TRANSPORT service. | ||
5350 | |||
5351 | The HOSTLIST component is functionally located between the PEERINFO and | ||
5352 | the TRANSPORT subsystem. When acting as a server, the daemon obtains valid | ||
5353 | (@emph{validated}) peer information (HELLO messages) from the PEERINFO | ||
5354 | service and provides it to other peers. When acting as a client, it | ||
5355 | contacts the HOSTLIST servers specified in the configuration, downloads | ||
5356 | the (unvalidated) list of HELLO messages and forwards these information | ||
5357 | to the TRANSPORT server to validate the addresses. | ||
5358 | |||
5359 | @cindex HOSTLIST daemon | ||
5360 | @node The HOSTLIST daemon | ||
5361 | @subsection The HOSTLIST daemon | ||
5362 | |||
5363 | @c %**end of header | ||
5364 | |||
5365 | The hostlist daemon is the main component of the HOSTLIST subsystem. It is | ||
5366 | started by the ARM service and (if configured) starts the HOSTLIST client | ||
5367 | and server components. | ||
5368 | |||
5369 | If the daemon provides a hostlist itself it can advertise it's own | ||
5370 | hostlist to other peers. To do so it sends a | ||
5371 | @code{GNUNET_MESSAGE_TYPE_HOSTLIST_ADVERTISEMENT} message to other peers | ||
5372 | when they connect to this peer on the CORE level. This hostlist | ||
5373 | advertisement message contains the URL to access the HOSTLIST HTTP | ||
5374 | server of the sender. The daemon may also subscribe to this type of | ||
5375 | message from CORE service, and then forward these kind of message to the | ||
5376 | HOSTLIST client. The client then uses all available URLs to download peer | ||
5377 | information when necessary. | ||
5378 | |||
5379 | When starting, the HOSTLIST daemon first connects to the CORE subsystem | ||
5380 | and if hostlist learning is enabled, registers a CORE handler to receive | ||
5381 | this kind of messages. Next it starts (if configured) the client and | ||
5382 | server. It passes pointers to CORE connect and disconnect and receive | ||
5383 | handlers where the client and server store their functions, so the daemon | ||
5384 | can notify them about CORE events. | ||
5385 | |||
5386 | To clean up on shutdown, the daemon has a cleaning task, shutting down all | ||
5387 | subsystems and disconnecting from CORE. | ||
5388 | |||
5389 | @cindex HOSTLIST server | ||
5390 | @node The HOSTLIST server | ||
5391 | @subsection The HOSTLIST server | ||
5392 | |||
5393 | @c %**end of header | ||
5394 | |||
5395 | The server provides a way for other peers to obtain HELLOs. Basically it | ||
5396 | is a small web server other peers can connect to and download a list of | ||
5397 | HELLOs using standard HTTP; it may also advertise the URL of the hostlist | ||
5398 | to other peers connecting on CORE level. | ||
5399 | |||
5400 | |||
5401 | @menu | ||
5402 | * The HTTP Server:: | ||
5403 | * Advertising the URL:: | ||
5404 | @end menu | ||
5405 | |||
5406 | @node The HTTP Server | ||
5407 | @subsubsection The HTTP Server | ||
5408 | |||
5409 | @c %**end of header | ||
5410 | |||
5411 | During startup, the server starts a web server listening on the port | ||
5412 | specified with the HTTPPORT value (default 8080). In addition it connects | ||
5413 | to the PEERINFO service to obtain peer information. The HOSTLIST server | ||
5414 | uses the GNUNET_PEERINFO_iterate function to request HELLO information for | ||
5415 | all peers and adds their information to a new hostlist if they are | ||
5416 | suitable (expired addresses and HELLOs without addresses are both not | ||
5417 | suitable) and the maximum size for a hostlist is not exceeded | ||
5418 | (MAX_BYTES_PER_HOSTLISTS = 500000). | ||
5419 | When PEERINFO finishes (with a last NULL callback), the server destroys | ||
5420 | the previous hostlist response available for download on the web server | ||
5421 | and replaces it with the updated hostlist. The hostlist format is | ||
5422 | basically a sequence of HELLO messages (as obtained from PEERINFO) without | ||
5423 | any special tokenization. Since each HELLO message contains a size field, | ||
5424 | the response can easily be split into separate HELLO messages by the | ||
5425 | client. | ||
5426 | |||
5427 | A HOSTLIST client connecting to the HOSTLIST server will receive the | ||
5428 | hostlist as a HTTP response and the the server will terminate the | ||
5429 | connection with the result code @code{HTTP 200 OK}. | ||
5430 | The connection will be closed immediately if no hostlist is available. | ||
5431 | |||
5432 | @node Advertising the URL | ||
5433 | @subsubsection Advertising the URL | ||
5434 | |||
5435 | @c %**end of header | ||
5436 | |||
5437 | The server also advertises the URL to download the hostlist to other peers | ||
5438 | if hostlist advertisement is enabled. | ||
5439 | When a new peer connects and has hostlist learning enabled, the server | ||
5440 | sends a @code{GNUNET_MESSAGE_TYPE_HOSTLIST_ADVERTISEMENT} message to this | ||
5441 | peer using the CORE service. | ||
5442 | |||
5443 | @cindex HOSTLIST client | ||
5444 | @node The HOSTLIST client | ||
5445 | @subsection The HOSTLIST client | ||
5446 | |||
5447 | @c %**end of header | ||
5448 | |||
5449 | The client provides the functionality to download the list of HELLOs from | ||
5450 | a set of URLs. | ||
5451 | It performs a standard HTTP request to the URLs configured and learned | ||
5452 | from advertisement messages received from other peers. When a HELLO is | ||
5453 | downloaded, the HOSTLIST client forwards the HELLO to the TRANSPORT | ||
5454 | service for validation. | ||
5455 | |||
5456 | The client supports two modes of operation: | ||
5457 | |||
5458 | @itemize @bullet | ||
5459 | @item download of HELLOs (bootstrapping) | ||
5460 | @item learning of URLs | ||
5461 | @end itemize | ||
5462 | |||
5463 | @menu | ||
5464 | * Bootstrapping:: | ||
5465 | * Learning:: | ||
5466 | @end menu | ||
5467 | |||
5468 | @node Bootstrapping | ||
5469 | @subsubsection Bootstrapping | ||
5470 | |||
5471 | @c %**end of header | ||
5472 | |||
5473 | For bootstrapping, it schedules a task to download the hostlist from the | ||
5474 | set of known URLs. | ||
5475 | The downloads are only performed if the number of current | ||
5476 | connections is smaller than a minimum number of connections | ||
5477 | (at the moment 4). | ||
5478 | The interval between downloads increases exponentially; however, the | ||
5479 | exponential growth is limited if it becomes longer than an hour. | ||
5480 | At that point, the frequency growth is capped at | ||
5481 | (#number of connections * 1h). | ||
5482 | |||
5483 | Once the decision has been taken to download HELLOs, the daemon chooses a | ||
5484 | random URL from the list of known URLs. URLs can be configured in the | ||
5485 | configuration or be learned from advertisement messages. | ||
5486 | The client uses a HTTP client library (libcurl) to initiate the download | ||
5487 | using the libcurl multi interface. | ||
5488 | Libcurl passes the data to the callback_download function which | ||
5489 | stores the data in a buffer if space is available and the maximum size for | ||
5490 | a hostlist download is not exceeded (MAX_BYTES_PER_HOSTLISTS = 500000). | ||
5491 | When a full HELLO was downloaded, the HOSTLIST client offers this | ||
5492 | HELLO message to the TRANSPORT service for validation. | ||
5493 | When the download is finished or failed, statistical information about the | ||
5494 | quality of this URL is updated. | ||
5495 | |||
5496 | @cindex HOSTLIST learning | ||
5497 | @node Learning | ||
5498 | @subsubsection Learning | ||
5499 | |||
5500 | @c %**end of header | ||
5501 | |||
5502 | The client also manages hostlist advertisements from other peers. The | ||
5503 | HOSTLIST daemon forwards @code{GNUNET_MESSAGE_TYPE_HOSTLIST_ADVERTISEMENT} | ||
5504 | messages to the client subsystem, which extracts the URL from the message. | ||
5505 | Next, a test of the newly obtained URL is performed by triggering a | ||
5506 | download from the new URL. If the URL works correctly, it is added to the | ||
5507 | list of working URLs. | ||
5508 | |||
5509 | The size of the list of URLs is restricted, so if an additional server is | ||
5510 | added and the list is full, the URL with the worst quality ranking | ||
5511 | (determined through successful downloads and number of HELLOs e.g.) is | ||
5512 | discarded. During shutdown the list of URLs is saved to a file for | ||
5513 | persistance and loaded on startup. URLs from the configuration file are | ||
5514 | never discarded. | ||
5515 | |||
5516 | @node Usage | ||
5517 | @subsection Usage | ||
5518 | |||
5519 | @c %**end of header | ||
5520 | |||
5521 | To start HOSTLIST by default, it has to be added to the DEFAULTSERVICES | ||
5522 | section for the ARM services. This is done in the default configuration. | ||
5523 | |||
5524 | For more information on how to configure the HOSTLIST subsystem see the | ||
5525 | installation handbook:@ | ||
5526 | Configuring the hostlist to bootstrap@ | ||
5527 | Configuring your peer to provide a hostlist | ||
5528 | |||
5529 | @cindex IDENTITY Subsystem | ||
5530 | @node IDENTITY Subsystem | ||
5531 | @section IDENTITY Subsystem | ||
5532 | |||
5533 | @c %**end of header | ||
5534 | |||
5535 | Identities of "users" in GNUnet are called egos. | ||
5536 | Egos can be used as pseudonyms ("fake names") or be tied to an | ||
5537 | organization (for example, "GNU") or even the actual identity of a human. | ||
5538 | GNUnet users are expected to have many egos. They might have one tied to | ||
5539 | their real identity, some for organizations they manage, and more for | ||
5540 | different domains where they want to operate under a pseudonym. | ||
5541 | |||
5542 | The IDENTITY service allows users to manage their egos. The identity | ||
5543 | service manages the private keys egos of the local user; it does not | ||
5544 | manage identities of other users (public keys). Public keys for other | ||
5545 | users need names to become manageable. GNUnet uses the | ||
5546 | @dfn{GNU Name System} (GNS) to give names to other users and manage their | ||
5547 | public keys securely. This chapter is about the IDENTITY service, | ||
5548 | which is about the management of private keys. | ||
5549 | |||
5550 | On the network, an ego corresponds to an ECDSA key (over Curve25519, | ||
5551 | using RFC 6979, as required by GNS). Thus, users can perform actions | ||
5552 | under a particular ego by using (signing with) a particular private key. | ||
5553 | Other users can then confirm that the action was really performed by that | ||
5554 | ego by checking the signature against the respective public key. | ||
5555 | |||
5556 | The IDENTITY service allows users to associate a human-readable name with | ||
5557 | each ego. This way, users can use names that will remind them of the | ||
5558 | purpose of a particular ego. | ||
5559 | The IDENTITY service will store the respective private keys and | ||
5560 | allows applications to access key information by name. | ||
5561 | Users can change the name that is locally (!) associated with an ego. | ||
5562 | Egos can also be deleted, which means that the private key will be removed | ||
5563 | and it thus will not be possible to perform actions with that ego in the | ||
5564 | future. | ||
5565 | |||
5566 | Additionally, the IDENTITY subsystem can associate service functions with | ||
5567 | egos. | ||
5568 | For example, GNS requires the ego that should be used for the shorten | ||
5569 | zone. GNS will ask IDENTITY for an ego for the "gns-short" service. | ||
5570 | The IDENTITY service has a mapping of such service strings to the name of | ||
5571 | the ego that the user wants to use for this service, for example | ||
5572 | "my-short-zone-ego". | ||
5573 | |||
5574 | Finally, the IDENTITY API provides access to a special ego, the | ||
5575 | anonymous ego. The anonymous ego is special in that its private key is not | ||
5576 | really private, but fixed and known to everyone. | ||
5577 | Thus, anyone can perform actions as anonymous. This can be useful as with | ||
5578 | this trick, code does not have to contain a special case to distinguish | ||
5579 | between anonymous and pseudonymous egos. | ||
5580 | |||
5581 | @menu | ||
5582 | * libgnunetidentity:: | ||
5583 | * The IDENTITY Client-Service Protocol:: | ||
5584 | @end menu | ||
5585 | |||
5586 | @cindex libgnunetidentity | ||
5587 | @node libgnunetidentity | ||
5588 | @subsection libgnunetidentity | ||
5589 | @c %**end of header | ||
5590 | |||
5591 | |||
5592 | @menu | ||
5593 | * Connecting to the service:: | ||
5594 | * Operations on Egos:: | ||
5595 | * The anonymous Ego:: | ||
5596 | * Convenience API to lookup a single ego:: | ||
5597 | * Associating egos with service functions:: | ||
5598 | @end menu | ||
5599 | |||
5600 | @node Connecting to the service | ||
5601 | @subsubsection Connecting to the service | ||
5602 | |||
5603 | @c %**end of header | ||
5604 | |||
5605 | First, typical clients connect to the identity service using | ||
5606 | @code{GNUNET_IDENTITY_connect}. This function takes a callback as a | ||
5607 | parameter. | ||
5608 | If the given callback parameter is non-null, it will be invoked to notify | ||
5609 | the application about the current state of the identities in the system. | ||
5610 | |||
5611 | @itemize @bullet | ||
5612 | @item First, it will be invoked on all known egos at the time of the | ||
5613 | connection. For each ego, a handle to the ego and the user's name for the | ||
5614 | ego will be passed to the callback. Furthermore, a @code{void **} context | ||
5615 | argument will be provided which gives the client the opportunity to | ||
5616 | associate some state with the ego. | ||
5617 | @item Second, the callback will be invoked with NULL for the ego, the name | ||
5618 | and the context. This signals that the (initial) iteration over all egos | ||
5619 | has completed. | ||
5620 | @item Then, the callback will be invoked whenever something changes about | ||
5621 | an ego. | ||
5622 | If an ego is renamed, the callback is invoked with the ego handle of the | ||
5623 | ego that was renamed, and the new name. If an ego is deleted, the callback | ||
5624 | is invoked with the ego handle and a name of NULL. In the deletion case, | ||
5625 | the application should also release resources stored in the context. | ||
5626 | @item When the application destroys the connection to the identity service | ||
5627 | using @code{GNUNET_IDENTITY_disconnect}, the callback is again invoked | ||
5628 | with the ego and a name of NULL (equivalent to deletion of the egos). | ||
5629 | This should again be used to clean up the per-ego context. | ||
5630 | @end itemize | ||
5631 | |||
5632 | The ego handle passed to the callback remains valid until the callback is | ||
5633 | invoked with a name of NULL, so it is safe to store a reference to the | ||
5634 | ego's handle. | ||
5635 | |||
5636 | @node Operations on Egos | ||
5637 | @subsubsection Operations on Egos | ||
5638 | |||
5639 | @c %**end of header | ||
5640 | |||
5641 | Given an ego handle, the main operations are to get its associated private | ||
5642 | key using @code{GNUNET_IDENTITY_ego_get_private_key} or its associated | ||
5643 | public key using @code{GNUNET_IDENTITY_ego_get_public_key}. | ||
5644 | |||
5645 | The other operations on egos are pretty straightforward. | ||
5646 | Using @code{GNUNET_IDENTITY_create}, an application can request the | ||
5647 | creation of an ego by specifying the desired name. | ||
5648 | The operation will fail if that name is | ||
5649 | already in use. Using @code{GNUNET_IDENTITY_rename} the name of an | ||
5650 | existing ego can be changed. Finally, egos can be deleted using | ||
5651 | @code{GNUNET_IDENTITY_delete}. All of these operations will trigger | ||
5652 | updates to the callback given to the @code{GNUNET_IDENTITY_connect} | ||
5653 | function of all applications that are connected with the identity service | ||
5654 | at the time. @code{GNUNET_IDENTITY_cancel} can be used to cancel the | ||
5655 | operations before the respective continuations would be called. | ||
5656 | It is not guaranteed that the operation will not be completed anyway, | ||
5657 | only the continuation will no longer be called. | ||
5658 | |||
5659 | @node The anonymous Ego | ||
5660 | @subsubsection The anonymous Ego | ||
5661 | |||
5662 | @c %**end of header | ||
5663 | |||
5664 | A special way to obtain an ego handle is to call | ||
5665 | @code{GNUNET_IDENTITY_ego_get_anonymous}, which returns an ego for the | ||
5666 | "anonymous" user --- anyone knows and can get the private key for this | ||
5667 | user, so it is suitable for operations that are supposed to be anonymous | ||
5668 | but require signatures (for example, to avoid a special path in the code). | ||
5669 | The anonymous ego is always valid and accessing it does not require a | ||
5670 | connection to the identity service. | ||
5671 | |||
5672 | @node Convenience API to lookup a single ego | ||
5673 | @subsubsection Convenience API to lookup a single ego | ||
5674 | |||
5675 | |||
5676 | As applications commonly simply have to lookup a single ego, there is a | ||
5677 | convenience API to do just that. Use @code{GNUNET_IDENTITY_ego_lookup} to | ||
5678 | lookup a single ego by name. Note that this is the user's name for the | ||
5679 | ego, not the service function. The resulting ego will be returned via a | ||
5680 | callback and will only be valid during that callback. The operation can | ||
5681 | be cancelled via @code{GNUNET_IDENTITY_ego_lookup_cancel} | ||
5682 | (cancellation is only legal before the callback is invoked). | ||
5683 | |||
5684 | @node Associating egos with service functions | ||
5685 | @subsubsection Associating egos with service functions | ||
5686 | |||
5687 | |||
5688 | The @code{GNUNET_IDENTITY_set} function is used to associate a particular | ||
5689 | ego with a service function. The name used by the service and the ego are | ||
5690 | given as arguments. | ||
5691 | Afterwards, the service can use its name to lookup the associated ego | ||
5692 | using @code{GNUNET_IDENTITY_get}. | ||
5693 | |||
5694 | @node The IDENTITY Client-Service Protocol | ||
5695 | @subsection The IDENTITY Client-Service Protocol | ||
5696 | |||
5697 | @c %**end of header | ||
5698 | |||
5699 | A client connecting to the identity service first sends a message with | ||
5700 | type | ||
5701 | @code{GNUNET_MESSAGE_TYPE_IDENTITY_START} to the service. After that, the | ||
5702 | client will receive information about changes to the egos by receiving | ||
5703 | messages of type @code{GNUNET_MESSAGE_TYPE_IDENTITY_UPDATE}. | ||
5704 | Those messages contain the private key of the ego and the user's name of | ||
5705 | the ego (or zero bytes for the name to indicate that the ego was deleted). | ||
5706 | A special bit @code{end_of_list} is used to indicate the end of the | ||
5707 | initial iteration over the identity service's egos. | ||
5708 | |||
5709 | The client can trigger changes to the egos by sending @code{CREATE}, | ||
5710 | @code{RENAME} or @code{DELETE} messages. | ||
5711 | The CREATE message contains the private key and the desired name.@ | ||
5712 | The RENAME message contains the old name and the new name.@ | ||
5713 | The DELETE message only needs to include the name of the ego to delete.@ | ||
5714 | The service responds to each of these messages with a @code{RESULT_CODE} | ||
5715 | message which indicates success or error of the operation, and possibly | ||
5716 | a human-readable error message. | ||
5717 | |||
5718 | Finally, the client can bind the name of a service function to an ego by | ||
5719 | sending a @code{SET_DEFAULT} message with the name of the service function | ||
5720 | and the private key of the ego. | ||
5721 | Such bindings can then be resolved using a @code{GET_DEFAULT} message, | ||
5722 | which includes the name of the service function. The identity service | ||
5723 | will respond to a GET_DEFAULT request with a SET_DEFAULT message | ||
5724 | containing the respective information, or with a RESULT_CODE to | ||
5725 | indicate an error. | ||
5726 | |||
5727 | @cindex NAMESTORE Subsystem | ||
5728 | @node NAMESTORE Subsystem | ||
5729 | @section NAMESTORE Subsystem | ||
5730 | |||
5731 | The NAMESTORE subsystem provides persistent storage for local GNS zone | ||
5732 | information. All local GNS zone information are managed by NAMESTORE. It | ||
5733 | provides both the functionality to administer local GNS information (e.g. | ||
5734 | delete and add records) as well as to retrieve GNS information (e.g to | ||
5735 | list name information in a client). | ||
5736 | NAMESTORE does only manage the persistent storage of zone information | ||
5737 | belonging to the user running the service: GNS information from other | ||
5738 | users obtained from the DHT are stored by the NAMECACHE subsystem. | ||
5739 | |||
5740 | NAMESTORE uses a plugin-based database backend to store GNS information | ||
5741 | with good performance. Here sqlite, MySQL and PostgreSQL are supported | ||
5742 | database backends. | ||
5743 | NAMESTORE clients interact with the IDENTITY subsystem to obtain | ||
5744 | cryptographic information about zones based on egos as described with the | ||
5745 | IDENTITY subsystem, but internally NAMESTORE refers to zones using the | ||
5746 | ECDSA private key. | ||
5747 | In addition, it collaborates with the NAMECACHE subsystem and | ||
5748 | stores zone information when local information are modified in the | ||
5749 | GNS cache to increase look-up performance for local information. | ||
5750 | |||
5751 | NAMESTORE provides functionality to look-up and store records, to iterate | ||
5752 | over a specific or all zones and to monitor zones for changes. NAMESTORE | ||
5753 | functionality can be accessed using the NAMESTORE api or the NAMESTORE | ||
5754 | command line tool. | ||
5755 | |||
5756 | @menu | ||
5757 | * libgnunetnamestore:: | ||
5758 | @end menu | ||
5759 | |||
5760 | @cindex libgnunetnamestore | ||
5761 | @node libgnunetnamestore | ||
5762 | @subsection libgnunetnamestore | ||
5763 | |||
5764 | To interact with NAMESTORE clients first connect to the NAMESTORE service | ||
5765 | using the @code{GNUNET_NAMESTORE_connect} passing a configuration handle. | ||
5766 | As a result they obtain a NAMESTORE handle, they can use for operations, | ||
5767 | or NULL is returned if the connection failed. | ||
5768 | |||
5769 | To disconnect from NAMESTORE, clients use | ||
5770 | @code{GNUNET_NAMESTORE_disconnect} and specify the handle to disconnect. | ||
5771 | |||
5772 | NAMESTORE internally uses the ECDSA private key to refer to zones. These | ||
5773 | private keys can be obtained from the IDENTITY subsytem. | ||
5774 | Here @emph{egos} @emph{can be used to refer to zones or the default ego | ||
5775 | assigned to the GNS subsystem can be used to obtained the master zone's | ||
5776 | private key.} | ||
5777 | |||
5778 | |||
5779 | @menu | ||
5780 | * Editing Zone Information:: | ||
5781 | * Iterating Zone Information:: | ||
5782 | * Monitoring Zone Information:: | ||
5783 | @end menu | ||
5784 | |||
5785 | @node Editing Zone Information | ||
5786 | @subsubsection Editing Zone Information | ||
5787 | |||
5788 | @c %**end of header | ||
5789 | |||
5790 | NAMESTORE provides functions to lookup records stored under a label in a | ||
5791 | zone and to store records under a label in a zone. | ||
5792 | |||
5793 | To store (and delete) records, the client uses the | ||
5794 | @code{GNUNET_NAMESTORE_records_store} function and has to provide | ||
5795 | namestore handle to use, the private key of the zone, the label to store | ||
5796 | the records under, the records and number of records plus an callback | ||
5797 | function. | ||
5798 | After the operation is performed NAMESTORE will call the provided | ||
5799 | callback function with the result GNUNET_SYSERR on failure | ||
5800 | (including timeout/queue drop/failure to validate), GNUNET_NO if content | ||
5801 | was already there or not found GNUNET_YES (or other positive value) on | ||
5802 | success plus an additional error message. | ||
5803 | |||
5804 | Records are deleted by using the store command with 0 records to store. | ||
5805 | It is important to note, that records are not merged when records exist | ||
5806 | with the label. | ||
5807 | So a client has first to retrieve records, merge with existing records | ||
5808 | and then store the result. | ||
5809 | |||
5810 | To perform a lookup operation, the client uses the | ||
5811 | @code{GNUNET_NAMESTORE_records_store} function. Here he has to pass the | ||
5812 | namestore handle, the private key of the zone and the label. He also has | ||
5813 | to provide a callback function which will be called with the result of | ||
5814 | the lookup operation: | ||
5815 | the zone for the records, the label, and the records including the | ||
5816 | number of records included. | ||
5817 | |||
5818 | A special operation is used to set the preferred nickname for a zone. | ||
5819 | This nickname is stored with the zone and is automatically merged with | ||
5820 | all labels and records stored in a zone. Here the client uses the | ||
5821 | @code{GNUNET_NAMESTORE_set_nick} function and passes the private key of | ||
5822 | the zone, the nickname as string plus a the callback with the result of | ||
5823 | the operation. | ||
5824 | |||
5825 | @node Iterating Zone Information | ||
5826 | @subsubsection Iterating Zone Information | ||
5827 | |||
5828 | @c %**end of header | ||
5829 | |||
5830 | A client can iterate over all information in a zone or all zones managed | ||
5831 | by NAMESTORE. | ||
5832 | Here a client uses the @code{GNUNET_NAMESTORE_zone_iteration_start} | ||
5833 | function and passes the namestore handle, the zone to iterate over and a | ||
5834 | callback function to call with the result. | ||
5835 | If the client wants to iterate over all the, he passes NULL for the zone. | ||
5836 | A @code{GNUNET_NAMESTORE_ZoneIterator} handle is returned to be used to | ||
5837 | continue iteration. | ||
5838 | |||
5839 | NAMESTORE calls the callback for every result and expects the client to | ||
5840 | call @code{GNUNET_NAMESTORE_zone_iterator_next} to continue to iterate or | ||
5841 | @code{GNUNET_NAMESTORE_zone_iterator_stop} to interrupt the iteration. | ||
5842 | When NAMESTORE reached the last item it will call the callback with a | ||
5843 | NULL value to indicate. | ||
5844 | |||
5845 | @node Monitoring Zone Information | ||
5846 | @subsubsection Monitoring Zone Information | ||
5847 | |||
5848 | @c %**end of header | ||
5849 | |||
5850 | Clients can also monitor zones to be notified about changes. Here the | ||
5851 | clients uses the @code{GNUNET_NAMESTORE_zone_monitor_start} function and | ||
5852 | passes the private key of the zone and and a callback function to call | ||
5853 | with updates for a zone. | ||
5854 | The client can specify to obtain zone information first by iterating over | ||
5855 | the zone and specify a synchronization callback to be called when the | ||
5856 | client and the namestore are synced. | ||
5857 | |||
5858 | On an update, NAMESTORE will call the callback with the private key of the | ||
5859 | zone, the label and the records and their number. | ||
5860 | |||
5861 | To stop monitoring, the client calls | ||
5862 | @code{GNUNET_NAMESTORE_zone_monitor_stop} and passes the handle obtained | ||
5863 | from the function to start the monitoring. | ||
5864 | |||
5865 | @cindex PEERINFO Subsystem | ||
5866 | @node PEERINFO Subsystem | ||
5867 | @section PEERINFO Subsystem | ||
5868 | |||
5869 | @c %**end of header | ||
5870 | |||
5871 | The PEERINFO subsystem is used to store verified (validated) information | ||
5872 | about known peers in a persistent way. It obtains these addresses for | ||
5873 | example from TRANSPORT service which is in charge of address validation. | ||
5874 | Validation means that the information in the HELLO message are checked by | ||
5875 | connecting to the addresses and performing a cryptographic handshake to | ||
5876 | authenticate the peer instance stating to be reachable with these | ||
5877 | addresses. | ||
5878 | Peerinfo does not validate the HELLO messages itself but only stores them | ||
5879 | and gives them to interested clients. | ||
5880 | |||
5881 | As future work, we think about moving from storing just HELLO messages to | ||
5882 | providing a generic persistent per-peer information store. | ||
5883 | More and more subsystems tend to need to store per-peer information in | ||
5884 | persistent way. | ||
5885 | To not duplicate this functionality we plan to provide a PEERSTORE | ||
5886 | service providing this functionality. | ||
5887 | |||
5888 | @menu | ||
5889 | * PEERINFO - Features:: | ||
5890 | * PEERINFO - Limitations:: | ||
5891 | * DeveloperPeer Information:: | ||
5892 | * Startup:: | ||
5893 | * Managing Information:: | ||
5894 | * Obtaining Information:: | ||
5895 | * The PEERINFO Client-Service Protocol:: | ||
5896 | * libgnunetpeerinfo:: | ||
5897 | @end menu | ||
5898 | |||
5899 | @node PEERINFO - Features | ||
5900 | @subsection PEERINFO - Features | ||
5901 | |||
5902 | @c %**end of header | ||
5903 | |||
5904 | @itemize @bullet | ||
5905 | @item Persistent storage | ||
5906 | @item Client notification mechanism on update | ||
5907 | @item Periodic clean up for expired information | ||
5908 | @item Differentiation between public and friend-only HELLO | ||
5909 | @end itemize | ||
5910 | |||
5911 | @node PEERINFO - Limitations | ||
5912 | @subsection PEERINFO - Limitations | ||
5913 | |||
5914 | |||
5915 | @itemize @bullet | ||
5916 | @item Does not perform HELLO validation | ||
5917 | @end itemize | ||
5918 | |||
5919 | @node DeveloperPeer Information | ||
5920 | @subsection DeveloperPeer Information | ||
5921 | |||
5922 | @c %**end of header | ||
5923 | |||
5924 | The PEERINFO subsystem stores these information in the form of HELLO | ||
5925 | messages you can think of as business cards. | ||
5926 | These HELLO messages contain the public key of a peer and the addresses | ||
5927 | a peer can be reached under. | ||
5928 | The addresses include an expiration date describing how long they are | ||
5929 | valid. This information is updated regularly by the TRANSPORT service by | ||
5930 | revalidating the address. | ||
5931 | If an address is expired and not renewed, it can be removed from the | ||
5932 | HELLO message. | ||
5933 | |||
5934 | Some peer do not want to have their HELLO messages distributed to other | ||
5935 | peers, especially when GNUnet's friend-to-friend modus is enabled. | ||
5936 | To prevent this undesired distribution. PEERINFO distinguishes between | ||
5937 | @emph{public} and @emph{friend-only} HELLO messages. | ||
5938 | Public HELLO messages can be freely distributed to other (possibly | ||
5939 | unknown) peers (for example using the hostlist, gossiping, broadcasting), | ||
5940 | whereas friend-only HELLO messages may not be distributed to other peers. | ||
5941 | Friend-only HELLO messages have an additional flag @code{friend_only} set | ||
5942 | internally. For public HELLO message this flag is not set. | ||
5943 | PEERINFO does and cannot not check if a client is allowed to obtain a | ||
5944 | specific HELLO type. | ||
5945 | |||
5946 | The HELLO messages can be managed using the GNUnet HELLO library. | ||
5947 | Other GNUnet systems can obtain these information from PEERINFO and use | ||
5948 | it for their purposes. | ||
5949 | Clients are for example the HOSTLIST component providing these | ||
5950 | information to other peers in form of a hostlist or the TRANSPORT | ||
5951 | subsystem using these information to maintain connections to other peers. | ||
5952 | |||
5953 | @node Startup | ||
5954 | @subsection Startup | ||
5955 | |||
5956 | @c %**end of header | ||
5957 | |||
5958 | During startup the PEERINFO services loads persistent HELLOs from disk. | ||
5959 | First PEERINFO parses the directory configured in the HOSTS value of the | ||
5960 | @code{PEERINFO} configuration section to store PEERINFO information. | ||
5961 | For all files found in this directory valid HELLO messages are extracted. | ||
5962 | In addition it loads HELLO messages shipped with the GNUnet distribution. | ||
5963 | These HELLOs are used to simplify network bootstrapping by providing | ||
5964 | valid peer information with the distribution. | ||
5965 | The use of these HELLOs can be prevented by setting the | ||
5966 | @code{USE_INCLUDED_HELLOS} in the @code{PEERINFO} configuration section to | ||
5967 | @code{NO}. Files containing invalid information are removed. | ||
5968 | |||
5969 | @node Managing Information | ||
5970 | @subsection Managing Information | ||
5971 | |||
5972 | @c %**end of header | ||
5973 | |||
5974 | The PEERINFO services stores information about known PEERS and a single | ||
5975 | HELLO message for every peer. | ||
5976 | A peer does not need to have a HELLO if no information are available. | ||
5977 | HELLO information from different sources, for example a HELLO obtained | ||
5978 | from a remote HOSTLIST and a second HELLO stored on disk, are combined | ||
5979 | and merged into one single HELLO message per peer which will be given to | ||
5980 | clients. During this merge process the HELLO is immediately written to | ||
5981 | disk to ensure persistence. | ||
5982 | |||
5983 | PEERINFO in addition periodically scans the directory where information | ||
5984 | are stored for empty HELLO messages with expired TRANSPORT addresses. | ||
5985 | This periodic task scans all files in the directory and recreates the | ||
5986 | HELLO messages it finds. | ||
5987 | Expired TRANSPORT addresses are removed from the HELLO and if the | ||
5988 | HELLO does not contain any valid addresses, it is discarded and removed | ||
5989 | from the disk. | ||
5990 | |||
5991 | @node Obtaining Information | ||
5992 | @subsection Obtaining Information | ||
5993 | |||
5994 | @c %**end of header | ||
5995 | |||
5996 | When a client requests information from PEERINFO, PEERINFO performs a | ||
5997 | lookup for the respective peer or all peers if desired and transmits this | ||
5998 | information to the client. | ||
5999 | The client can specify if friend-only HELLOs have to be included or not | ||
6000 | and PEERINFO filters the respective HELLO messages before transmitting | ||
6001 | information. | ||
6002 | |||
6003 | To notify clients about changes to PEERINFO information, PEERINFO | ||
6004 | maintains a list of clients interested in this notifications. | ||
6005 | Such a notification occurs if a HELLO for a peer was updated (due to a | ||
6006 | merge for example) or a new peer was added. | ||
6007 | |||
6008 | @node The PEERINFO Client-Service Protocol | ||
6009 | @subsection The PEERINFO Client-Service Protocol | ||
6010 | |||
6011 | @c %**end of header | ||
6012 | |||
6013 | To connect and disconnect to and from the PEERINFO Service PEERINFO | ||
6014 | utilizes the util client/server infrastructure, so no special messages | ||
6015 | types are used here. | ||
6016 | |||
6017 | To add information for a peer, the plain HELLO message is transmitted to | ||
6018 | the service without any wrapping. All pieces of information required are | ||
6019 | stored within the HELLO message. | ||
6020 | The PEERINFO service provides a message handler accepting and processing | ||
6021 | these HELLO messages. | ||
6022 | |||
6023 | When obtaining PEERINFO information using the iterate functionality | ||
6024 | specific messages are used. To obtain information for all peers, a | ||
6025 | @code{struct ListAllPeersMessage} with message type | ||
6026 | @code{GNUNET_MESSAGE_TYPE_PEERINFO_GET_ALL} and a flag | ||
6027 | include_friend_only to indicate if friend-only HELLO messages should be | ||
6028 | included are transmitted. If information for a specific peer is required | ||
6029 | a @code{struct ListAllPeersMessage} with | ||
6030 | @code{GNUNET_MESSAGE_TYPE_PEERINFO_GET} containing the peer identity is | ||
6031 | used. | ||
6032 | |||
6033 | For both variants the PEERINFO service replies for each HELLO message it | ||
6034 | wants to transmit with a @code{struct ListAllPeersMessage} with type | ||
6035 | @code{GNUNET_MESSAGE_TYPE_PEERINFO_INFO} containing the plain HELLO. | ||
6036 | The final message is @code{struct GNUNET_MessageHeader} with type | ||
6037 | @code{GNUNET_MESSAGE_TYPE_PEERINFO_INFO}. If the client receives this | ||
6038 | message, it can proceed with the next request if any is pending. | ||
6039 | |||
6040 | @node libgnunetpeerinfo | ||
6041 | @subsection libgnunetpeerinfo | ||
6042 | |||
6043 | @c %**end of header | ||
6044 | |||
6045 | The PEERINFO API consists mainly of three different functionalities: | ||
6046 | |||
6047 | @itemize @bullet | ||
6048 | @item maintaining a connection to the service | ||
6049 | @item adding new information to the PEERINFO service | ||
6050 | @item retrieving information from the PEERINFO service | ||
6051 | @end itemize | ||
6052 | |||
6053 | @menu | ||
6054 | * Connecting to the PEERINFO Service:: | ||
6055 | * Adding Information to the PEERINFO Service:: | ||
6056 | * Obtaining Information from the PEERINFO Service:: | ||
6057 | @end menu | ||
6058 | |||
6059 | @node Connecting to the PEERINFO Service | ||
6060 | @subsubsection Connecting to the PEERINFO Service | ||
6061 | |||
6062 | @c %**end of header | ||
6063 | |||
6064 | To connect to the PEERINFO service the function | ||
6065 | @code{GNUNET_PEERINFO_connect} is used, taking a configuration handle as | ||
6066 | an argument, and to disconnect from PEERINFO the function | ||
6067 | @code{GNUNET_PEERINFO_disconnect}, taking the PEERINFO | ||
6068 | handle returned from the connect function has to be called. | ||
6069 | |||
6070 | @node Adding Information to the PEERINFO Service | ||
6071 | @subsubsection Adding Information to the PEERINFO Service | ||
6072 | |||
6073 | @c %**end of header | ||
6074 | |||
6075 | @code{GNUNET_PEERINFO_add_peer} adds a new peer to the PEERINFO subsystem | ||
6076 | storage. This function takes the PEERINFO handle as an argument, the HELLO | ||
6077 | message to store and a continuation with a closure to be called with the | ||
6078 | result of the operation. | ||
6079 | The @code{GNUNET_PEERINFO_add_peer} returns a handle to this operation | ||
6080 | allowing to cancel the operation with the respective cancel function | ||
6081 | @code{GNUNET_PEERINFO_add_peer_cancel}. To retrieve information from | ||
6082 | PEERINFO you can iterate over all information stored with PEERINFO or you | ||
6083 | can tell PEERINFO to notify if new peer information are available. | ||
6084 | |||
6085 | @node Obtaining Information from the PEERINFO Service | ||
6086 | @subsubsection Obtaining Information from the PEERINFO Service | ||
6087 | |||
6088 | @c %**end of header | ||
6089 | |||
6090 | To iterate over information in PEERINFO you use | ||
6091 | @code{GNUNET_PEERINFO_iterate}. | ||
6092 | This function expects the PEERINFO handle, a flag if HELLO messages | ||
6093 | intended for friend only mode should be included, a timeout how long the | ||
6094 | operation should take and a callback with a callback closure to be called | ||
6095 | for the results. | ||
6096 | If you want to obtain information for a specific peer, you can specify | ||
6097 | the peer identity, if this identity is NULL, information for all peers are | ||
6098 | returned. The function returns a handle to allow to cancel the operation | ||
6099 | using @code{GNUNET_PEERINFO_iterate_cancel}. | ||
6100 | |||
6101 | To get notified when peer information changes, you can use | ||
6102 | @code{GNUNET_PEERINFO_notify}. | ||
6103 | This function expects a configuration handle and a flag if friend-only | ||
6104 | HELLO messages should be included. The PEERINFO service will notify you | ||
6105 | about every change and the callback function will be called to notify you | ||
6106 | about changes. The function returns a handle to cancel notifications | ||
6107 | with @code{GNUNET_PEERINFO_notify_cancel}. | ||
6108 | |||
6109 | @cindex PEERSTORE Subsystem | ||
6110 | @node PEERSTORE Subsystem | ||
6111 | @section PEERSTORE Subsystem | ||
6112 | |||
6113 | @c %**end of header | ||
6114 | |||
6115 | GNUnet's PEERSTORE subsystem offers persistent per-peer storage for other | ||
6116 | GNUnet subsystems. GNUnet subsystems can use PEERSTORE to persistently | ||
6117 | store and retrieve arbitrary data. | ||
6118 | Each data record stored with PEERSTORE contains the following fields: | ||
6119 | |||
6120 | @itemize @bullet | ||
6121 | @item subsystem: Name of the subsystem responsible for the record. | ||
6122 | @item peerid: Identity of the peer this record is related to. | ||
6123 | @item key: a key string identifying the record. | ||
6124 | @item value: binary record value. | ||
6125 | @item expiry: record expiry date. | ||
6126 | @end itemize | ||
6127 | |||
6128 | @menu | ||
6129 | * Functionality:: | ||
6130 | * Architecture:: | ||
6131 | * libgnunetpeerstore:: | ||
6132 | @end menu | ||
6133 | |||
6134 | @node Functionality | ||
6135 | @subsection Functionality | ||
6136 | |||
6137 | @c %**end of header | ||
6138 | |||
6139 | Subsystems can store any type of value under a (subsystem, peerid, key) | ||
6140 | combination. A "replace" flag set during store operations forces the | ||
6141 | PEERSTORE to replace any old values stored under the same | ||
6142 | (subsystem, peerid, key) combination with the new value. | ||
6143 | Additionally, an expiry date is set after which the record is *possibly* | ||
6144 | deleted by PEERSTORE. | ||
6145 | |||
6146 | Subsystems can iterate over all values stored under any of the following | ||
6147 | combination of fields: | ||
6148 | |||
6149 | @itemize @bullet | ||
6150 | @item (subsystem) | ||
6151 | @item (subsystem, peerid) | ||
6152 | @item (subsystem, key) | ||
6153 | @item (subsystem, peerid, key) | ||
6154 | @end itemize | ||
6155 | |||
6156 | Subsystems can also request to be notified about any new values stored | ||
6157 | under a (subsystem, peerid, key) combination by sending a "watch" | ||
6158 | request to PEERSTORE. | ||
6159 | |||
6160 | @node Architecture | ||
6161 | @subsection Architecture | ||
6162 | |||
6163 | @c %**end of header | ||
6164 | |||
6165 | PEERSTORE implements the following components: | ||
6166 | |||
6167 | @itemize @bullet | ||
6168 | @item PEERSTORE service: Handles store, iterate and watch operations. | ||
6169 | @item PEERSTORE API: API to be used by other subsystems to communicate and | ||
6170 | issue commands to the PEERSTORE service. | ||
6171 | @item PEERSTORE plugins: Handles the persistent storage. At the moment, | ||
6172 | only an "sqlite" plugin is implemented. | ||
6173 | @end itemize | ||
6174 | |||
6175 | @cindex libgnunetpeerstore | ||
6176 | @node libgnunetpeerstore | ||
6177 | @subsection libgnunetpeerstore | ||
6178 | |||
6179 | @c %**end of header | ||
6180 | |||
6181 | libgnunetpeerstore is the library containing the PEERSTORE API. Subsystems | ||
6182 | wishing to communicate with the PEERSTORE service use this API to open a | ||
6183 | connection to PEERSTORE. This is done by calling | ||
6184 | @code{GNUNET_PEERSTORE_connect} which returns a handle to the newly | ||
6185 | created connection. | ||
6186 | This handle has to be used with any further calls to the API. | ||
6187 | |||
6188 | To store a new record, the function @code{GNUNET_PEERSTORE_store} is to | ||
6189 | be used which requires the record fields and a continuation function that | ||
6190 | will be called by the API after the STORE request is sent to the | ||
6191 | PEERSTORE service. | ||
6192 | Note that calling the continuation function does not mean that the record | ||
6193 | is successfully stored, only that the STORE request has been successfully | ||
6194 | sent to the PEERSTORE service. | ||
6195 | @code{GNUNET_PEERSTORE_store_cancel} can be called to cancel the STORE | ||
6196 | request only before the continuation function has been called. | ||
6197 | |||
6198 | To iterate over stored records, the function | ||
6199 | @code{GNUNET_PEERSTORE_iterate} is | ||
6200 | to be used. @emph{peerid} and @emph{key} can be set to NULL. An iterator | ||
6201 | callback function will be called with each matching record found and a | ||
6202 | NULL record at the end to signal the end of result set. | ||
6203 | @code{GNUNET_PEERSTORE_iterate_cancel} can be used to cancel the ITERATE | ||
6204 | request before the iterator callback is called with a NULL record. | ||
6205 | |||
6206 | To be notified with new values stored under a (subsystem, peerid, key) | ||
6207 | combination, the function @code{GNUNET_PEERSTORE_watch} is to be used. | ||
6208 | This will register the watcher with the PEERSTORE service, any new | ||
6209 | records matching the given combination will trigger the callback | ||
6210 | function passed to @code{GNUNET_PEERSTORE_watch}. This continues until | ||
6211 | @code{GNUNET_PEERSTORE_watch_cancel} is called or the connection to the | ||
6212 | service is destroyed. | ||
6213 | |||
6214 | After the connection is no longer needed, the function | ||
6215 | @code{GNUNET_PEERSTORE_disconnect} can be called to disconnect from the | ||
6216 | PEERSTORE service. | ||
6217 | Any pending ITERATE or WATCH requests will be destroyed. | ||
6218 | If the @code{sync_first} flag is set to @code{GNUNET_YES}, the API will | ||
6219 | delay the disconnection until all pending STORE requests are sent to | ||
6220 | the PEERSTORE service, otherwise, the pending STORE requests will be | ||
6221 | destroyed as well. | ||
6222 | |||
6223 | @cindex SET Subsystem | ||
6224 | @node SET Subsystem | ||
6225 | @section SET Subsystem | ||
6226 | |||
6227 | @c %**end of header | ||
6228 | |||
6229 | The SET service implements efficient set operations between two peers | ||
6230 | over a mesh tunnel. | ||
6231 | Currently, set union and set intersection are the only supported | ||
6232 | operations. Elements of a set consist of an @emph{element type} and | ||
6233 | arbitrary binary @emph{data}. | ||
6234 | The size of an element's data is limited to around 62 KB. | ||
6235 | |||
6236 | @menu | ||
6237 | * Local Sets:: | ||
6238 | * Set Modifications:: | ||
6239 | * Set Operations:: | ||
6240 | * Result Elements:: | ||
6241 | * libgnunetset:: | ||
6242 | * The SET Client-Service Protocol:: | ||
6243 | * The SET Intersection Peer-to-Peer Protocol:: | ||
6244 | * The SET Union Peer-to-Peer Protocol:: | ||
6245 | @end menu | ||
6246 | |||
6247 | @node Local Sets | ||
6248 | @subsection Local Sets | ||
6249 | |||
6250 | @c %**end of header | ||
6251 | |||
6252 | Sets created by a local client can be modified and reused for multiple | ||
6253 | operations. As each set operation requires potentially expensive special | ||
6254 | auxilliary data to be computed for each element of a set, a set can only | ||
6255 | participate in one type of set operation (i.e. union or intersection). | ||
6256 | The type of a set is determined upon its creation. | ||
6257 | If a the elements of a set are needed for an operation of a different | ||
6258 | type, all of the set's element must be copied to a new set of appropriate | ||
6259 | type. | ||
6260 | |||
6261 | @node Set Modifications | ||
6262 | @subsection Set Modifications | ||
6263 | |||
6264 | @c %**end of header | ||
6265 | |||
6266 | Even when set operations are active, one can add to and remove elements | ||
6267 | from a set. | ||
6268 | However, these changes will only be visible to operations that have been | ||
6269 | created after the changes have taken place. That is, every set operation | ||
6270 | only sees a snapshot of the set from the time the operation was started. | ||
6271 | This mechanism is @emph{not} implemented by copying the whole set, but by | ||
6272 | attaching @emph{generation information} to each element and operation. | ||
6273 | |||
6274 | @node Set Operations | ||
6275 | @subsection Set Operations | ||
6276 | |||
6277 | @c %**end of header | ||
6278 | |||
6279 | Set operations can be started in two ways: Either by accepting an | ||
6280 | operation request from a remote peer, or by requesting a set operation | ||
6281 | from a remote peer. | ||
6282 | Set operations are uniquely identified by the involved @emph{peers}, an | ||
6283 | @emph{application id} and the @emph{operation type}. | ||
6284 | |||
6285 | The client is notified of incoming set operations by @emph{set listeners}. | ||
6286 | A set listener listens for incoming operations of a specific operation | ||
6287 | type and application id. | ||
6288 | Once notified of an incoming set request, the client can accept the set | ||
6289 | request (providing a local set for the operation) or reject it. | ||
6290 | |||
6291 | @node Result Elements | ||
6292 | @subsection Result Elements | ||
6293 | |||
6294 | @c %**end of header | ||
6295 | |||
6296 | The SET service has three @emph{result modes} that determine how an | ||
6297 | operation's result set is delivered to the client: | ||
6298 | |||
6299 | @itemize @bullet | ||
6300 | @item @strong{Full Result Set.} All elements of set resulting from the set | ||
6301 | operation are returned to the client. | ||
6302 | @item @strong{Added Elements.} Only elements that result from the | ||
6303 | operation and are not already in the local peer's set are returned. | ||
6304 | Note that for some operations (like set intersection) this result mode | ||
6305 | will never return any elements. | ||
6306 | This can be useful if only the remove peer is actually interested in | ||
6307 | the result of the set operation. | ||
6308 | @item @strong{Removed Elements.} Only elements that are in the local | ||
6309 | peer's initial set but not in the operation's result set are returned. | ||
6310 | Note that for some operations (like set union) this result mode will | ||
6311 | never return any elements. This can be useful if only the remove peer is | ||
6312 | actually interested in the result of the set operation. | ||
6313 | @end itemize | ||
6314 | |||
6315 | @cindex libgnunetset | ||
6316 | @node libgnunetset | ||
6317 | @subsection libgnunetset | ||
6318 | |||
6319 | @c %**end of header | ||
6320 | |||
6321 | @menu | ||
6322 | * Sets:: | ||
6323 | * Listeners:: | ||
6324 | * Operations:: | ||
6325 | * Supplying a Set:: | ||
6326 | * The Result Callback:: | ||
6327 | @end menu | ||
6328 | |||
6329 | @node Sets | ||
6330 | @subsubsection Sets | ||
6331 | |||
6332 | @c %**end of header | ||
6333 | |||
6334 | New sets are created with @code{GNUNET_SET_create}. Both the local peer's | ||
6335 | configuration (as each set has its own client connection) and the | ||
6336 | operation type must be specified. | ||
6337 | The set exists until either the client calls @code{GNUNET_SET_destroy} or | ||
6338 | the client's connection to the service is disrupted. | ||
6339 | In the latter case, the client is notified by the return value of | ||
6340 | functions dealing with sets. This return value must always be checked. | ||
6341 | |||
6342 | Elements are added and removed with @code{GNUNET_SET_add_element} and | ||
6343 | @code{GNUNET_SET_remove_element}. | ||
6344 | |||
6345 | @node Listeners | ||
6346 | @subsubsection Listeners | ||
6347 | |||
6348 | @c %**end of header | ||
6349 | |||
6350 | Listeners are created with @code{GNUNET_SET_listen}. Each time time a | ||
6351 | remote peer suggests a set operation with an application id and operation | ||
6352 | type matching a listener, the listener's callback is invoked. | ||
6353 | The client then must synchronously call either @code{GNUNET_SET_accept} | ||
6354 | or @code{GNUNET_SET_reject}. Note that the operation will not be started | ||
6355 | until the client calls @code{GNUNET_SET_commit} | ||
6356 | (see Section "Supplying a Set"). | ||
6357 | |||
6358 | @node Operations | ||
6359 | @subsubsection Operations | ||
6360 | |||
6361 | @c %**end of header | ||
6362 | |||
6363 | Operations to be initiated by the local peer are created with | ||
6364 | @code{GNUNET_SET_prepare}. Note that the operation will not be started | ||
6365 | until the client calls @code{GNUNET_SET_commit} | ||
6366 | (see Section "Supplying a Set"). | ||
6367 | |||
6368 | @node Supplying a Set | ||
6369 | @subsubsection Supplying a Set | ||
6370 | |||
6371 | @c %**end of header | ||
6372 | |||
6373 | To create symmetry between the two ways of starting a set operation | ||
6374 | (accepting and nitiating it), the operation handles returned by | ||
6375 | @code{GNUNET_SET_accept} and @code{GNUNET_SET_prepare} do not yet have a | ||
6376 | set to operate on, thus they can not do any work yet. | ||
6377 | |||
6378 | The client must call @code{GNUNET_SET_commit} to specify a set to use for | ||
6379 | an operation. @code{GNUNET_SET_commit} may only be called once per set | ||
6380 | operation. | ||
6381 | |||
6382 | @node The Result Callback | ||
6383 | @subsubsection The Result Callback | ||
6384 | |||
6385 | @c %**end of header | ||
6386 | |||
6387 | Clients must specify both a result mode and a result callback with | ||
6388 | @code{GNUNET_SET_accept} and @code{GNUNET_SET_prepare}. The result | ||
6389 | callback with a status indicating either that an element was received, or | ||
6390 | the operation failed or succeeded. | ||
6391 | The interpretation of the received element depends on the result mode. | ||
6392 | The callback needs to know which result mode it is used in, as the | ||
6393 | arguments do not indicate if an element is part of the full result set, | ||
6394 | or if it is in the difference between the original set and the final set. | ||
6395 | |||
6396 | @node The SET Client-Service Protocol | ||
6397 | @subsection The SET Client-Service Protocol | ||
6398 | |||
6399 | @c %**end of header | ||
6400 | |||
6401 | @menu | ||
6402 | * Creating Sets:: | ||
6403 | * Listeners2:: | ||
6404 | * Initiating Operations:: | ||
6405 | * Modifying Sets:: | ||
6406 | * Results and Operation Status:: | ||
6407 | * Iterating Sets:: | ||
6408 | @end menu | ||
6409 | |||
6410 | @node Creating Sets | ||
6411 | @subsubsection Creating Sets | ||
6412 | |||
6413 | @c %**end of header | ||
6414 | |||
6415 | For each set of a client, there exists a client connection to the service. | ||
6416 | Sets are created by sending the @code{GNUNET_SERVICE_SET_CREATE} message | ||
6417 | over a new client connection. Multiple operations for one set are | ||
6418 | multiplexed over one client connection, using a request id supplied by | ||
6419 | the client. | ||
6420 | |||
6421 | @node Listeners2 | ||
6422 | @subsubsection Listeners2 | ||
6423 | |||
6424 | @c %**end of header | ||
6425 | |||
6426 | Each listener also requires a seperate client connection. By sending the | ||
6427 | @code{GNUNET_SERVICE_SET_LISTEN} message, the client notifies the service | ||
6428 | of the application id and operation type it is interested in. A client | ||
6429 | rejects an incoming request by sending @code{GNUNET_SERVICE_SET_REJECT} | ||
6430 | on the listener's client connection. | ||
6431 | In contrast, when accepting an incoming request, a | ||
6432 | @code{GNUNET_SERVICE_SET_ACCEPT} message must be sent over the@ set that | ||
6433 | is supplied for the set operation. | ||
6434 | |||
6435 | @node Initiating Operations | ||
6436 | @subsubsection Initiating Operations | ||
6437 | |||
6438 | @c %**end of header | ||
6439 | |||
6440 | Operations with remote peers are initiated by sending a | ||
6441 | @code{GNUNET_SERVICE_SET_EVALUATE} message to the service. The@ client | ||
6442 | connection that this message is sent by determines the set to use. | ||
6443 | |||
6444 | @node Modifying Sets | ||
6445 | @subsubsection Modifying Sets | ||
6446 | |||
6447 | @c %**end of header | ||
6448 | |||
6449 | Sets are modified with the @code{GNUNET_SERVICE_SET_ADD} and | ||
6450 | @code{GNUNET_SERVICE_SET_REMOVE} messages. | ||
6451 | |||
6452 | |||
6453 | @c %@menu | ||
6454 | @c %* Results and Operation Status:: | ||
6455 | @c %* Iterating Sets:: | ||
6456 | @c %@end menu | ||
6457 | |||
6458 | @node Results and Operation Status | ||
6459 | @subsubsection Results and Operation Status | ||
6460 | @c %**end of header | ||
6461 | |||
6462 | The service notifies the client of result elements and success/failure of | ||
6463 | a set operation with the @code{GNUNET_SERVICE_SET_RESULT} message. | ||
6464 | |||
6465 | @node Iterating Sets | ||
6466 | @subsubsection Iterating Sets | ||
6467 | |||
6468 | @c %**end of header | ||
6469 | |||
6470 | All elements of a set can be requested by sending | ||
6471 | @code{GNUNET_SERVICE_SET_ITER_REQUEST}. The server responds with | ||
6472 | @code{GNUNET_SERVICE_SET_ITER_ELEMENT} and eventually terminates the | ||
6473 | iteration with @code{GNUNET_SERVICE_SET_ITER_DONE}. | ||
6474 | After each received element, the client | ||
6475 | must send @code{GNUNET_SERVICE_SET_ITER_ACK}. Note that only one set | ||
6476 | iteration may be active for a set at any given time. | ||
6477 | |||
6478 | @node The SET Intersection Peer-to-Peer Protocol | ||
6479 | @subsection The SET Intersection Peer-to-Peer Protocol | ||
6480 | |||
6481 | @c %**end of header | ||
6482 | |||
6483 | The intersection protocol operates over CADET and starts with a | ||
6484 | GNUNET_MESSAGE_TYPE_SET_P2P_OPERATION_REQUEST being sent by the peer | ||
6485 | initiating the operation to the peer listening for inbound requests. | ||
6486 | It includes the number of elements of the initiating peer, which is used | ||
6487 | to decide which side will send a Bloom filter first. | ||
6488 | |||
6489 | The listening peer checks if the operation type and application | ||
6490 | identifier are acceptable for its current state. | ||
6491 | If not, it responds with a GNUNET_MESSAGE_TYPE_SET_RESULT and a status of | ||
6492 | GNUNET_SET_STATUS_FAILURE (and terminates the CADET channel). | ||
6493 | |||
6494 | If the application accepts the request, the listener sends back a | ||
6495 | @code{GNUNET_MESSAGE_TYPE_SET_INTERSECTION_P2P_ELEMENT_INFO} if it has | ||
6496 | more elements in the set than the client. | ||
6497 | Otherwise, it immediately starts with the Bloom filter exchange. | ||
6498 | If the initiator receives a | ||
6499 | @code{GNUNET_MESSAGE_TYPE_SET_INTERSECTION_P2P_ELEMENT_INFO} response, | ||
6500 | it beings the Bloom filter exchange, unless the set size is indicated to | ||
6501 | be zero, in which case the intersection is considered finished after | ||
6502 | just the initial handshake. | ||
6503 | |||
6504 | |||
6505 | @menu | ||
6506 | * The Bloom filter exchange:: | ||
6507 | * Salt:: | ||
6508 | @end menu | ||
6509 | |||
6510 | @node The Bloom filter exchange | ||
6511 | @subsubsection The Bloom filter exchange | ||
6512 | |||
6513 | @c %**end of header | ||
6514 | |||
6515 | In this phase, each peer transmits a Bloom filter over the remaining | ||
6516 | keys of the local set to the other peer using a | ||
6517 | @code{GNUNET_MESSAGE_TYPE_SET_INTERSECTION_P2P_BF} message. This | ||
6518 | message additionally includes the number of elements left in the sender's | ||
6519 | set, as well as the XOR over all of the keys in that set. | ||
6520 | |||
6521 | The number of bits 'k' set per element in the Bloom filter is calculated | ||
6522 | based on the relative size of the two sets. | ||
6523 | Furthermore, the size of the Bloom filter is calculated based on 'k' and | ||
6524 | the number of elements in the set to maximize the amount of data filtered | ||
6525 | per byte transmitted on the wire (while avoiding an excessively high | ||
6526 | number of iterations). | ||
6527 | |||
6528 | The receiver of the message removes all elements from its local set that | ||
6529 | do not pass the Bloom filter test. | ||
6530 | It then checks if the set size of the sender and the XOR over the keys | ||
6531 | match what is left of his own set. If they do, he sends a | ||
6532 | @code{GNUNET_MESSAGE_TYPE_SET_INTERSECTION_P2P_DONE} back to indicate | ||
6533 | that the latest set is the final result. | ||
6534 | Otherwise, the receiver starts another Bloom fitler exchange, except | ||
6535 | this time as the sender. | ||
6536 | |||
6537 | @node Salt | ||
6538 | @subsubsection Salt | ||
6539 | |||
6540 | @c %**end of header | ||
6541 | |||
6542 | Bloomfilter operations are probablistic: With some non-zero probability | ||
6543 | the test may incorrectly say an element is in the set, even though it is | ||
6544 | not. | ||
6545 | |||
6546 | To mitigate this problem, the intersection protocol iterates exchanging | ||
6547 | Bloom filters using a different random 32-bit salt in each iteration (the | ||
6548 | salt is also included in the message). | ||
6549 | With different salts, set operations may fail for different elements. | ||
6550 | Merging the results from the executions, the probability of failure drops | ||
6551 | to zero. | ||
6552 | |||
6553 | The iterations terminate once both peers have established that they have | ||
6554 | sets of the same size, and where the XOR over all keys computes the same | ||
6555 | 512-bit value (leaving a failure probability of 2-511). | ||
6556 | |||
6557 | @node The SET Union Peer-to-Peer Protocol | ||
6558 | @subsection The SET Union Peer-to-Peer Protocol | ||
6559 | |||
6560 | @c %**end of header | ||
6561 | |||
6562 | The SET union protocol is based on Eppstein's efficient set reconciliation | ||
6563 | without prior context. You should read this paper first if you want to | ||
6564 | understand the protocol. | ||
6565 | |||
6566 | The union protocol operates over CADET and starts with a | ||
6567 | GNUNET_MESSAGE_TYPE_SET_P2P_OPERATION_REQUEST being sent by the peer | ||
6568 | initiating the operation to the peer listening for inbound requests. | ||
6569 | It includes the number of elements of the initiating peer, which is | ||
6570 | currently not used. | ||
6571 | |||
6572 | The listening peer checks if the operation type and application | ||
6573 | identifier are acceptable for its current state. If not, it responds with | ||
6574 | a @code{GNUNET_MESSAGE_TYPE_SET_RESULT} and a status of | ||
6575 | @code{GNUNET_SET_STATUS_FAILURE} (and terminates the CADET channel). | ||
6576 | |||
6577 | If the application accepts the request, it sends back a strata estimator | ||
6578 | using a message of type GNUNET_MESSAGE_TYPE_SET_UNION_P2P_SE. The | ||
6579 | initiator evaluates the strata estimator and initiates the exchange of | ||
6580 | invertible Bloom filters, sending a GNUNET_MESSAGE_TYPE_SET_UNION_P2P_IBF. | ||
6581 | |||
6582 | During the IBF exchange, if the receiver cannot invert the Bloom filter or | ||
6583 | detects a cycle, it sends a larger IBF in response (up to a defined | ||
6584 | maximum limit; if that limit is reached, the operation fails). | ||
6585 | Elements decoded while processing the IBF are transmitted to the other | ||
6586 | peer using GNUNET_MESSAGE_TYPE_SET_P2P_ELEMENTS, or requested from the | ||
6587 | other peer using GNUNET_MESSAGE_TYPE_SET_P2P_ELEMENT_REQUESTS messages, | ||
6588 | depending on the sign observed during decoding of the IBF. | ||
6589 | Peers respond to a GNUNET_MESSAGE_TYPE_SET_P2P_ELEMENT_REQUESTS message | ||
6590 | with the respective element in a GNUNET_MESSAGE_TYPE_SET_P2P_ELEMENTS | ||
6591 | message. If the IBF fully decodes, the peer responds with a | ||
6592 | GNUNET_MESSAGE_TYPE_SET_UNION_P2P_DONE message instead of another | ||
6593 | GNUNET_MESSAGE_TYPE_SET_UNION_P2P_IBF. | ||
6594 | |||
6595 | All Bloom filter operations use a salt to mingle keys before hasing them | ||
6596 | into buckets, such that future iterations have a fresh chance of | ||
6597 | succeeding if they failed due to collisions before. | ||
6598 | |||
6599 | @cindex STATISTICS Subsystem | ||
6600 | @node STATISTICS Subsystem | ||
6601 | @section STATISTICS Subsystem | ||
6602 | |||
6603 | @c %**end of header | ||
6604 | |||
6605 | In GNUnet, the STATISTICS subsystem offers a central place for all | ||
6606 | subsystems to publish unsigned 64-bit integer run-time statistics. | ||
6607 | Keeping this information centrally means that there is a unified way for | ||
6608 | the user to obtain data on all subsystems, and individual subsystems do | ||
6609 | not have to always include a custom data export method for performance | ||
6610 | metrics and other statistics. For example, the TRANSPORT system uses | ||
6611 | STATISTICS to update information about the number of directly connected | ||
6612 | peers and the bandwidth that has been consumed by the various plugins. | ||
6613 | This information is valuable for diagnosing connectivity and performance | ||
6614 | issues. | ||
6615 | |||
6616 | Following the GNUnet service architecture, the STATISTICS subsystem is | ||
6617 | divided into an API which is exposed through the header | ||
6618 | @strong{gnunet_statistics_service.h} and the STATISTICS service | ||
6619 | @strong{gnunet-service-statistics}. The @strong{gnunet-statistics} | ||
6620 | command-line tool can be used to obtain (and change) information about | ||
6621 | the values stored by the STATISTICS service. The STATISTICS service does | ||
6622 | not communicate with other peers. | ||
6623 | |||
6624 | Data is stored in the STATISTICS service in the form of tuples | ||
6625 | @strong{(subsystem, name, value, persistence)}. The subsystem determines | ||
6626 | to which other GNUnet's subsystem the data belongs. name is the name | ||
6627 | through which value is associated. It uniquely identifies the record | ||
6628 | from among other records belonging to the same subsystem. | ||
6629 | In some parts of the code, the pair @strong{(subsystem, name)} is called | ||
6630 | a @strong{statistic} as it identifies the values stored in the STATISTCS | ||
6631 | service.The persistence flag determines if the record has to be preserved | ||
6632 | across service restarts. A record is said to be persistent if this flag | ||
6633 | is set for it; if not, the record is treated as a non-persistent record | ||
6634 | and it is lost after service restart. Persistent records are written to | ||
6635 | and read from the file @strong{statistics.data} before shutdown | ||
6636 | and upon startup. The file is located in the HOME directory of the peer. | ||
6637 | |||
6638 | An anomaly of the STATISTICS service is that it does not terminate | ||
6639 | immediately upon receiving a shutdown signal if it has any clients | ||
6640 | connected to it. It waits for all the clients that are not monitors to | ||
6641 | close their connections before terminating itself. | ||
6642 | This is to prevent the loss of data during peer shutdown --- delaying the | ||
6643 | STATISTICS service shutdown helps other services to store important data | ||
6644 | to STATISTICS during shutdown. | ||
6645 | |||
6646 | @menu | ||
6647 | * libgnunetstatistics:: | ||
6648 | * The STATISTICS Client-Service Protocol:: | ||
6649 | @end menu | ||
6650 | |||
6651 | @cindex libgnunetstatistics | ||
6652 | @node libgnunetstatistics | ||
6653 | @subsection libgnunetstatistics | ||
6654 | |||
6655 | @c %**end of header | ||
6656 | |||
6657 | @strong{libgnunetstatistics} is the library containing the API for the | ||
6658 | STATISTICS subsystem. Any process requiring to use STATISTICS should use | ||
6659 | this API by to open a connection to the STATISTICS service. | ||
6660 | This is done by calling the function @code{GNUNET_STATISTICS_create()}. | ||
6661 | This function takes the subsystem's name which is trying to use STATISTICS | ||
6662 | and a configuration. | ||
6663 | All values written to STATISTICS with this connection will be placed in | ||
6664 | the section corresponding to the given subsystem's name. | ||
6665 | The connection to STATISTICS can be destroyed with the function | ||
6666 | @code{GNUNET_STATISTICS_destroy()}. This function allows for the | ||
6667 | connection to be destroyed immediately or upon transferring all | ||
6668 | pending write requests to the service. | ||
6669 | |||
6670 | Note: STATISTICS subsystem can be disabled by setting @code{DISABLE = YES} | ||
6671 | under the @code{[STATISTICS]} section in the configuration. With such a | ||
6672 | configuration all calls to @code{GNUNET_STATISTICS_create()} return | ||
6673 | @code{NULL} as the STATISTICS subsystem is unavailable and no other | ||
6674 | functions from the API can be used. | ||
6675 | |||
6676 | |||
6677 | @menu | ||
6678 | * Statistics retrieval:: | ||
6679 | * Setting statistics and updating them:: | ||
6680 | * Watches:: | ||
6681 | @end menu | ||
6682 | |||
6683 | @node Statistics retrieval | ||
6684 | @subsubsection Statistics retrieval | ||
6685 | |||
6686 | @c %**end of header | ||
6687 | |||
6688 | Once a connection to the statistics service is obtained, information | ||
6689 | about any other system which uses statistics can be retrieved with the | ||
6690 | function GNUNET_STATISTICS_get(). | ||
6691 | This function takes the connection handle, the name of the subsystem | ||
6692 | whose information we are interested in (a @code{NULL} value will | ||
6693 | retrieve information of all available subsystems using STATISTICS), the | ||
6694 | name of the statistic we are interested in (a @code{NULL} value will | ||
6695 | retrieve all available statistics), a continuation callback which is | ||
6696 | called when all of requested information is retrieved, an iterator | ||
6697 | callback which is called for each parameter in the retrieved information | ||
6698 | and a closure for the aforementioned callbacks. The library then invokes | ||
6699 | the iterator callback for each value matching the request. | ||
6700 | |||
6701 | Call to @code{GNUNET_STATISTICS_get()} is asynchronous and can be | ||
6702 | canceled with the function @code{GNUNET_STATISTICS_get_cancel()}. | ||
6703 | This is helpful when retrieving statistics takes too long and especially | ||
6704 | when we want to shutdown and cleanup everything. | ||
6705 | |||
6706 | @node Setting statistics and updating them | ||
6707 | @subsubsection Setting statistics and updating them | ||
6708 | |||
6709 | @c %**end of header | ||
6710 | |||
6711 | So far we have seen how to retrieve statistics, here we will learn how we | ||
6712 | can set statistics and update them so that other subsystems can retrieve | ||
6713 | them. | ||
6714 | |||
6715 | A new statistic can be set using the function | ||
6716 | @code{GNUNET_STATISTICS_set()}. | ||
6717 | This function takes the name of the statistic and its value and a flag to | ||
6718 | make the statistic persistent. | ||
6719 | The value of the statistic should be of the type @code{uint64_t}. | ||
6720 | The function does not take the name of the subsystem; it is determined | ||
6721 | from the previous @code{GNUNET_STATISTICS_create()} invocation. If | ||
6722 | the given statistic is already present, its value is overwritten. | ||
6723 | |||
6724 | An existing statistics can be updated, i.e its value can be increased or | ||
6725 | decreased by an amount with the function | ||
6726 | @code{GNUNET_STATISTICS_update()}. | ||
6727 | The parameters to this function are similar to | ||
6728 | @code{GNUNET_STATISTICS_set()}, except that it takes the amount to be | ||
6729 | changed as a type @code{int64_t} instead of the value. | ||
6730 | |||
6731 | The library will combine multiple set or update operations into one | ||
6732 | message if the client performs requests at a rate that is faster than the | ||
6733 | available IPC with the STATISTICS service. Thus, the client does not have | ||
6734 | to worry about sending requests too quickly. | ||
6735 | |||
6736 | @node Watches | ||
6737 | @subsubsection Watches | ||
6738 | |||
6739 | @c %**end of header | ||
6740 | |||
6741 | As interesting feature of STATISTICS lies in serving notifications | ||
6742 | whenever a statistic of our interest is modified. | ||
6743 | This is achieved by registering a watch through the function | ||
6744 | @code{GNUNET_STATISTICS_watch()}. | ||
6745 | The parameters of this function are similar to those of | ||
6746 | @code{GNUNET_STATISTICS_get()}. | ||
6747 | Changes to the respective statistic's value will then cause the given | ||
6748 | iterator callback to be called. | ||
6749 | Note: A watch can only be registered for a specific statistic. Hence | ||
6750 | the subsystem name and the parameter name cannot be @code{NULL} in a | ||
6751 | call to @code{GNUNET_STATISTICS_watch()}. | ||
6752 | |||
6753 | A registered watch will keep notifying any value changes until | ||
6754 | @code{GNUNET_STATISTICS_watch_cancel()} is called with the same | ||
6755 | parameters that are used for registering the watch. | ||
6756 | |||
6757 | @node The STATISTICS Client-Service Protocol | ||
6758 | @subsection The STATISTICS Client-Service Protocol | ||
6759 | @c %**end of header | ||
6760 | |||
6761 | |||
6762 | @menu | ||
6763 | * Statistics retrieval2:: | ||
6764 | * Setting and updating statistics:: | ||
6765 | * Watching for updates:: | ||
6766 | @end menu | ||
6767 | |||
6768 | @node Statistics retrieval2 | ||
6769 | @subsubsection Statistics retrieval2 | ||
6770 | |||
6771 | @c %**end of header | ||
6772 | |||
6773 | To retrieve statistics, the client transmits a message of type | ||
6774 | @code{GNUNET_MESSAGE_TYPE_STATISTICS_GET} containing the given subsystem | ||
6775 | name and statistic parameter to the STATISTICS service. | ||
6776 | The service responds with a message of type | ||
6777 | @code{GNUNET_MESSAGE_TYPE_STATISTICS_VALUE} for each of the statistics | ||
6778 | parameters that match the client request for the client. The end of | ||
6779 | information retrieved is signaled by the service by sending a message of | ||
6780 | type @code{GNUNET_MESSAGE_TYPE_STATISTICS_END}. | ||
6781 | |||
6782 | @node Setting and updating statistics | ||
6783 | @subsubsection Setting and updating statistics | ||
6784 | |||
6785 | @c %**end of header | ||
6786 | |||
6787 | The subsystem name, parameter name, its value and the persistence flag are | ||
6788 | communicated to the service through the message | ||
6789 | @code{GNUNET_MESSAGE_TYPE_STATISTICS_SET}. | ||
6790 | |||
6791 | When the service receives a message of type | ||
6792 | @code{GNUNET_MESSAGE_TYPE_STATISTICS_SET}, it retrieves the subsystem | ||
6793 | name and checks for a statistic parameter with matching the name given in | ||
6794 | the message. | ||
6795 | If a statistic parameter is found, the value is overwritten by the new | ||
6796 | value from the message; if not found then a new statistic parameter is | ||
6797 | created with the given name and value. | ||
6798 | |||
6799 | In addition to just setting an absolute value, it is possible to perform a | ||
6800 | relative update by sending a message of type | ||
6801 | @code{GNUNET_MESSAGE_TYPE_STATISTICS_SET} with an update flag | ||
6802 | (@code{GNUNET_STATISTICS_SETFLAG_RELATIVE}) signifying that the value in | ||
6803 | the message should be treated as an update value. | ||
6804 | |||
6805 | @node Watching for updates | ||
6806 | @subsubsection Watching for updates | ||
6807 | |||
6808 | @c %**end of header | ||
6809 | |||
6810 | The function registers the watch at the service by sending a message of | ||
6811 | type @code{GNUNET_MESSAGE_TYPE_STATISTICS_WATCH}. The service then sends | ||
6812 | notifications through messages of type | ||
6813 | @code{GNUNET_MESSAGE_TYPE_STATISTICS_WATCH_VALUE} whenever the statistic | ||
6814 | parameter's value is changed. | ||
6815 | |||
6816 | @cindex DHT | ||
6817 | @cindex Distributed Hash Table | ||
6818 | @node Distributed Hash Table (DHT) | ||
6819 | @section Distributed Hash Table (DHT) | ||
6820 | |||
6821 | @c %**end of header | ||
6822 | |||
6823 | GNUnet includes a generic distributed hash table that can be used by | ||
6824 | developers building P2P applications in the framework. | ||
6825 | This section documents high-level features and how developers are | ||
6826 | expected to use the DHT. | ||
6827 | We have a research paper detailing how the DHT works. | ||
6828 | Also, Nate's thesis includes a detailed description and performance | ||
6829 | analysis (in chapter 6). | ||
6830 | |||
6831 | Key features of GNUnet's DHT include: | ||
6832 | |||
6833 | @itemize @bullet | ||
6834 | @item stores key-value pairs with values up to (approximately) 63k in size | ||
6835 | @item works with many underlay network topologies (small-world, random | ||
6836 | graph), underlay does not need to be a full mesh / clique | ||
6837 | @item support for extended queries (more than just a simple 'key'), | ||
6838 | filtering duplicate replies within the network (bloomfilter) and content | ||
6839 | validation (for details, please read the subsection on the block library) | ||
6840 | @item can (optionally) return paths taken by the PUT and GET operations | ||
6841 | to the application | ||
6842 | @item provides content replication to handle churn | ||
6843 | @end itemize | ||
6844 | |||
6845 | GNUnet's DHT is randomized and unreliable. Unreliable means that there is | ||
6846 | no strict guarantee that a value stored in the DHT is always | ||
6847 | found --- values are only found with high probability. | ||
6848 | While this is somewhat true in all P2P DHTs, GNUnet developers should be | ||
6849 | particularly wary of this fact (this will help you write secure, | ||
6850 | fault-tolerant code). Thus, when writing any application using the DHT, | ||
6851 | you should always consider the possibility that a value stored in the | ||
6852 | DHT by you or some other peer might simply not be returned, or returned | ||
6853 | with a significant delay. | ||
6854 | Your application logic must be written to tolerate this (naturally, some | ||
6855 | loss of performance or quality of service is expected in this case). | ||
6856 | |||
6857 | @menu | ||
6858 | * Block library and plugins:: | ||
6859 | * libgnunetdht:: | ||
6860 | * The DHT Client-Service Protocol:: | ||
6861 | * The DHT Peer-to-Peer Protocol:: | ||
6862 | @end menu | ||
6863 | |||
6864 | @node Block library and plugins | ||
6865 | @subsection Block library and plugins | ||
6866 | |||
6867 | @c %**end of header | ||
6868 | |||
6869 | @menu | ||
6870 | * What is a Block?:: | ||
6871 | * The API of libgnunetblock:: | ||
6872 | * Queries:: | ||
6873 | * Sample Code:: | ||
6874 | * Conclusion2:: | ||
6875 | @end menu | ||
6876 | |||
6877 | @node What is a Block? | ||
6878 | @subsubsection What is a Block? | ||
6879 | |||
6880 | @c %**end of header | ||
6881 | |||
6882 | Blocks are small (< 63k) pieces of data stored under a key (struct | ||
6883 | GNUNET_HashCode). Blocks have a type (enum GNUNET_BlockType) which defines | ||
6884 | their data format. Blocks are used in GNUnet as units of static data | ||
6885 | exchanged between peers and stored (or cached) locally. | ||
6886 | Uses of blocks include file-sharing (the files are broken up into blocks), | ||
6887 | the VPN (DNS information is stored in blocks) and the DHT (all | ||
6888 | information in the DHT and meta-information for the maintenance of the | ||
6889 | DHT are both stored using blocks). | ||
6890 | The block subsystem provides a few common functions that must be | ||
6891 | available for any type of block. | ||
6892 | |||
6893 | @cindex libgnunetblock API | ||
6894 | @node The API of libgnunetblock | ||
6895 | @subsubsection The API of libgnunetblock | ||
6896 | |||
6897 | @c %**end of header | ||
6898 | |||
6899 | The block library requires for each (family of) block type(s) a block | ||
6900 | plugin (implementing @file{gnunet_block_plugin.h}) that provides basic | ||
6901 | functions that are needed by the DHT (and possibly other subsystems) to | ||
6902 | manage the block. | ||
6903 | These block plugins are typically implemented within their respective | ||
6904 | subsystems. | ||
6905 | The main block library is then used to locate, load and query the | ||
6906 | appropriate block plugin. | ||
6907 | Which plugin is appropriate is determined by the block type (which is | ||
6908 | just a 32-bit integer). Block plugins contain code that specifies which | ||
6909 | block types are supported by a given plugin. The block library loads all | ||
6910 | block plugins that are installed at the local peer and forwards the | ||
6911 | application request to the respective plugin. | ||
6912 | |||
6913 | The central functions of the block APIs (plugin and main library) are to | ||
6914 | allow the mapping of blocks to their respective key (if possible) and the | ||
6915 | ability to check that a block is well-formed and matches a given | ||
6916 | request (again, if possible). | ||
6917 | This way, GNUnet can avoid storing invalid blocks, storing blocks under | ||
6918 | the wrong key and forwarding blocks in response to a query that they do | ||
6919 | not answer. | ||
6920 | |||
6921 | One key function of block plugins is that it allows GNUnet to detect | ||
6922 | duplicate replies (via the Bloom filter). All plugins MUST support | ||
6923 | detecting duplicate replies (by adding the current response to the | ||
6924 | Bloom filter and rejecting it if it is encountered again). | ||
6925 | If a plugin fails to do this, responses may loop in the network. | ||
6926 | |||
6927 | @node Queries | ||
6928 | @subsubsection Queries | ||
6929 | @c %**end of header | ||
6930 | |||
6931 | The query format for any block in GNUnet consists of four main components. | ||
6932 | First, the type of the desired block must be specified. Second, the query | ||
6933 | must contain a hash code. The hash code is used for lookups in hash | ||
6934 | tables and databases and must not be unique for the block (however, if | ||
6935 | possible a unique hash should be used as this would be best for | ||
6936 | performance). | ||
6937 | Third, an optional Bloom filter can be specified to exclude known results; | ||
6938 | replies that hash to the bits set in the Bloom filter are considered | ||
6939 | invalid. False-positives can be eliminated by sending the same query | ||
6940 | again with a different Bloom filter mutator value, which parameterizes | ||
6941 | the hash function that is used. | ||
6942 | Finally, an optional application-specific "eXtended query" (xquery) can | ||
6943 | be specified to further constrain the results. It is entirely up to | ||
6944 | the type-specific plugin to determine whether or not a given block | ||
6945 | matches a query (type, hash, Bloom filter, and xquery). | ||
6946 | Naturally, not all xquery's are valid and some types of blocks may not | ||
6947 | support Bloom filters either, so the plugin also needs to check if the | ||
6948 | query is valid in the first place. | ||
6949 | |||
6950 | Depending on the results from the plugin, the DHT will then discard the | ||
6951 | (invalid) query, forward the query, discard the (invalid) reply, cache the | ||
6952 | (valid) reply, and/or forward the (valid and non-duplicate) reply. | ||
6953 | |||
6954 | @node Sample Code | ||
6955 | @subsubsection Sample Code | ||
6956 | |||
6957 | @c %**end of header | ||
6958 | |||
6959 | The source code in @strong{plugin_block_test.c} is a good starting point | ||
6960 | for new block plugins --- it does the minimal work by implementing a | ||
6961 | plugin that performs no validation at all. | ||
6962 | The respective @strong{Makefile.am} shows how to build and install a | ||
6963 | block plugin. | ||
6964 | |||
6965 | @node Conclusion2 | ||
6966 | @subsubsection Conclusion2 | ||
6967 | |||
6968 | @c %**end of header | ||
6969 | |||
6970 | In conclusion, GNUnet subsystems that want to use the DHT need to define a | ||
6971 | block format and write a plugin to match queries and replies. For testing, | ||
6972 | the @code{GNUNET_BLOCK_TYPE_TEST} block type can be used; it accepts | ||
6973 | any query as valid and any reply as matching any query. | ||
6974 | This type is also used for the DHT command line tools. | ||
6975 | However, it should NOT be used for normal applications due to the lack | ||
6976 | of error checking that results from this primitive implementation. | ||
6977 | |||
6978 | @cindex libgnunetdht | ||
6979 | @node libgnunetdht | ||
6980 | @subsection libgnunetdht | ||
6981 | |||
6982 | @c %**end of header | ||
6983 | |||
6984 | The DHT API itself is pretty simple and offers the usual GET and PUT | ||
6985 | functions that work as expected. The specified block type refers to the | ||
6986 | block library which allows the DHT to run application-specific logic for | ||
6987 | data stored in the network. | ||
6988 | |||
6989 | |||
6990 | @menu | ||
6991 | * GET:: | ||
6992 | * PUT:: | ||
6993 | * MONITOR:: | ||
6994 | * DHT Routing Options:: | ||
6995 | @end menu | ||
6996 | |||
6997 | @node GET | ||
6998 | @subsubsection GET | ||
6999 | |||
7000 | @c %**end of header | ||
7001 | |||
7002 | When using GET, the main consideration for developers (other than the | ||
7003 | block library) should be that after issuing a GET, the DHT will | ||
7004 | continuously cause (small amounts of) network traffic until the operation | ||
7005 | is explicitly canceled. | ||
7006 | So GET does not simply send out a single network request once; instead, | ||
7007 | the DHT will continue to search for data. This is needed to achieve good | ||
7008 | success rates and also handles the case where the respective PUT | ||
7009 | operation happens after the GET operation was started. | ||
7010 | Developers should not cancel an existing GET operation and then | ||
7011 | explicitly re-start it to trigger a new round of network requests; | ||
7012 | this is simply inefficient, especially as the internal automated version | ||
7013 | can be more efficient, for example by filtering results in the network | ||
7014 | that have already been returned. | ||
7015 | |||
7016 | If an application that performs a GET request has a set of replies that it | ||
7017 | already knows and would like to filter, it can call@ | ||
7018 | @code{GNUNET_DHT_get_filter_known_results} with an array of hashes over | ||
7019 | the respective blocks to tell the DHT that these results are not | ||
7020 | desired (any more). | ||
7021 | This way, the DHT will filter the respective blocks using the block | ||
7022 | library in the network, which may result in a significant reduction in | ||
7023 | bandwidth consumption. | ||
7024 | |||
7025 | @node PUT | ||
7026 | @subsubsection PUT | ||
7027 | |||
7028 | @c %**end of header | ||
7029 | |||
7030 | In contrast to GET operations, developers @strong{must} manually re-run | ||
7031 | PUT operations periodically (if they intend the content to continue to be | ||
7032 | available). Content stored in the DHT expires or might be lost due to | ||
7033 | churn. | ||
7034 | Furthermore, GNUnet's DHT typically requires multiple rounds of PUT | ||
7035 | operations before a key-value pair is consistently available to all | ||
7036 | peers (the DHT randomizes paths and thus storage locations, and only | ||
7037 | after multiple rounds of PUTs there will be a sufficient number of | ||
7038 | replicas in large DHTs). An explicit PUT operation using the DHT API will | ||
7039 | only cause network traffic once, so in order to ensure basic availability | ||
7040 | and resistance to churn (and adversaries), PUTs must be repeated. | ||
7041 | While the exact frequency depends on the application, a rule of thumb is | ||
7042 | that there should be at least a dozen PUT operations within the content | ||
7043 | lifetime. Content in the DHT typically expires after one day, so | ||
7044 | DHT PUT operations should be repeated at least every 1-2 hours. | ||
7045 | |||
7046 | @node MONITOR | ||
7047 | @subsubsection MONITOR | ||
7048 | |||
7049 | @c %**end of header | ||
7050 | |||
7051 | The DHT API also allows applications to monitor messages crossing the | ||
7052 | local DHT service. | ||
7053 | The types of messages used by the DHT are GET, PUT and RESULT messages. | ||
7054 | Using the monitoring API, applications can choose to monitor these | ||
7055 | requests, possibly limiting themselves to requests for a particular block | ||
7056 | type. | ||
7057 | |||
7058 | The monitoring API is not only usefu only for diagnostics, it can also be | ||
7059 | used to trigger application operations based on PUT operations. | ||
7060 | For example, an application may use PUTs to distribute work requests to | ||
7061 | other peers. | ||
7062 | The workers would then monitor for PUTs that give them work, instead of | ||
7063 | looking for work using GET operations. | ||
7064 | This can be beneficial, especially if the workers have no good way to | ||
7065 | guess the keys under which work would be stored. | ||
7066 | Naturally, additional protocols might be needed to ensure that the desired | ||
7067 | number of workers will process the distributed workload. | ||
7068 | |||
7069 | @node DHT Routing Options | ||
7070 | @subsubsection DHT Routing Options | ||
7071 | |||
7072 | @c %**end of header | ||
7073 | |||
7074 | There are two important options for GET and PUT requests: | ||
7075 | |||
7076 | @table @asis | ||
7077 | @item GNUNET_DHT_RO_DEMULITPLEX_EVERYWHERE This option means that all | ||
7078 | peers should process the request, even if their peer ID is not closest to | ||
7079 | the key. For a PUT request, this means that all peers that a request | ||
7080 | traverses may make a copy of the data. | ||
7081 | Similarly for a GET request, all peers will check their local database | ||
7082 | for a result. Setting this option can thus significantly improve caching | ||
7083 | and reduce bandwidth consumption --- at the expense of a larger DHT | ||
7084 | database. If in doubt, we recommend that this option should be used. | ||
7085 | @item GNUNET_DHT_RO_RECORD_ROUTE This option instructs the DHT to record | ||
7086 | the path that a GET or a PUT request is taking through the overlay | ||
7087 | network. The resulting paths are then returned to the application with | ||
7088 | the respective result. This allows the receiver of a result to construct | ||
7089 | a path to the originator of the data, which might then be used for | ||
7090 | routing. Naturally, setting this option requires additional bandwidth | ||
7091 | and disk space, so applications should only set this if the paths are | ||
7092 | needed by the application logic. | ||
7093 | @item GNUNET_DHT_RO_FIND_PEER This option is an internal option used by | ||
7094 | the DHT's peer discovery mechanism and should not be used by applications. | ||
7095 | @item GNUNET_DHT_RO_BART This option is currently not implemented. It may | ||
7096 | in the future offer performance improvements for clique topologies. | ||
7097 | @end table | ||
7098 | |||
7099 | @node The DHT Client-Service Protocol | ||
7100 | @subsection The DHT Client-Service Protocol | ||
7101 | |||
7102 | @c %**end of header | ||
7103 | |||
7104 | @menu | ||
7105 | * PUTting data into the DHT:: | ||
7106 | * GETting data from the DHT:: | ||
7107 | * Monitoring the DHT:: | ||
7108 | @end menu | ||
7109 | |||
7110 | @node PUTting data into the DHT | ||
7111 | @subsubsection PUTting data into the DHT | ||
7112 | |||
7113 | @c %**end of header | ||
7114 | |||
7115 | To store (PUT) data into the DHT, the client sends a | ||
7116 | @code{struct GNUNET_DHT_ClientPutMessage} to the service. | ||
7117 | This message specifies the block type, routing options, the desired | ||
7118 | replication level, the expiration time, key, | ||
7119 | value and a 64-bit unique ID for the operation. The service responds with | ||
7120 | a @code{struct GNUNET_DHT_ClientPutConfirmationMessage} with the same | ||
7121 | 64-bit unique ID. Note that the service sends the confirmation as soon as | ||
7122 | it has locally processed the PUT request. The PUT may still be | ||
7123 | propagating through the network at this time. | ||
7124 | |||
7125 | In the future, we may want to change this to provide (limited) feedback | ||
7126 | to the client, for example if we detect that the PUT operation had no | ||
7127 | effect because the same key-value pair was already stored in the DHT. | ||
7128 | However, changing this would also require additional state and messages | ||
7129 | in the P2P interaction. | ||
7130 | |||
7131 | @node GETting data from the DHT | ||
7132 | @subsubsection GETting data from the DHT | ||
7133 | |||
7134 | @c %**end of header | ||
7135 | |||
7136 | To retrieve (GET) data from the DHT, the client sends a | ||
7137 | @code{struct GNUNET_DHT_ClientGetMessage} to the service. The message | ||
7138 | specifies routing options, a replication level (for replicating the GET, | ||
7139 | not the content), the desired block type, the key, the (optional) | ||
7140 | extended query and unique 64-bit request ID. | ||
7141 | |||
7142 | Additionally, the client may send any number of | ||
7143 | @code{struct GNUNET_DHT_ClientGetResultSeenMessage}s to notify the | ||
7144 | service about results that the client is already aware of. | ||
7145 | These messages consist of the key, the unique 64-bit ID of the request, | ||
7146 | and an arbitrary number of hash codes over the blocks that the client is | ||
7147 | already aware of. As messages are restricted to 64k, a client that | ||
7148 | already knows more than about a thousand blocks may need to send | ||
7149 | several of these messages. Naturally, the client should transmit these | ||
7150 | messages as quickly as possible after the original GET request such that | ||
7151 | the DHT can filter those results in the network early on. Naturally, as | ||
7152 | these messages are send after the original request, it is conceivalbe | ||
7153 | that the DHT service may return blocks that match those already known | ||
7154 | to the client anyway. | ||
7155 | |||
7156 | In response to a GET request, the service will send @code{struct | ||
7157 | GNUNET_DHT_ClientResultMessage}s to the client. These messages contain the | ||
7158 | block type, expiration, key, unique ID of the request and of course the | ||
7159 | value (a block). Depending on the options set for the respective | ||
7160 | operations, the replies may also contain the path the GET and/or the PUT | ||
7161 | took through the network. | ||
7162 | |||
7163 | A client can stop receiving replies either by disconnecting or by sending | ||
7164 | a @code{struct GNUNET_DHT_ClientGetStopMessage} which must contain the | ||
7165 | key and the 64-bit unique ID of the original request. Using an | ||
7166 | explicit "stop" message is more common as this allows a client to run | ||
7167 | many concurrent GET operations over the same connection with the DHT | ||
7168 | service --- and to stop them individually. | ||
7169 | |||
7170 | @node Monitoring the DHT | ||
7171 | @subsubsection Monitoring the DHT | ||
7172 | |||
7173 | @c %**end of header | ||
7174 | |||
7175 | To begin monitoring, the client sends a | ||
7176 | @code{struct GNUNET_DHT_MonitorStartStop} message to the DHT service. | ||
7177 | In this message, flags can be set to enable (or disable) monitoring of | ||
7178 | GET, PUT and RESULT messages that pass through a peer. The message can | ||
7179 | also restrict monitoring to a particular block type or a particular key. | ||
7180 | Once monitoring is enabled, the DHT service will notify the client about | ||
7181 | any matching event using @code{struct GNUNET_DHT_MonitorGetMessage}s for | ||
7182 | GET events, @code{struct GNUNET_DHT_MonitorPutMessage} for PUT events | ||
7183 | and @code{struct GNUNET_DHT_MonitorGetRespMessage} for RESULTs. Each of | ||
7184 | these messages contains all of the information about the event. | ||
7185 | |||
7186 | @node The DHT Peer-to-Peer Protocol | ||
7187 | @subsection The DHT Peer-to-Peer Protocol | ||
7188 | @c %**end of header | ||
7189 | |||
7190 | |||
7191 | @menu | ||
7192 | * Routing GETs or PUTs:: | ||
7193 | * PUTting data into the DHT2:: | ||
7194 | * GETting data from the DHT2:: | ||
7195 | @end menu | ||
7196 | |||
7197 | @node Routing GETs or PUTs | ||
7198 | @subsubsection Routing GETs or PUTs | ||
7199 | |||
7200 | @c %**end of header | ||
7201 | |||
7202 | When routing GETs or PUTs, the DHT service selects a suitable subset of | ||
7203 | neighbours for forwarding. The exact number of neighbours can be zero or | ||
7204 | more and depends on the hop counter of the query (initially zero) in | ||
7205 | relation to the (log of) the network size estimate, the desired | ||
7206 | replication level and the peer's connectivity. | ||
7207 | Depending on the hop counter and our network size estimate, the selection | ||
7208 | of the peers maybe randomized or by proximity to the key. | ||
7209 | Furthermore, requests include a set of peers that a request has already | ||
7210 | traversed; those peers are also excluded from the selection. | ||
7211 | |||
7212 | @node PUTting data into the DHT2 | ||
7213 | @subsubsection PUTting data into the DHT2 | ||
7214 | |||
7215 | @c %**end of header | ||
7216 | |||
7217 | To PUT data into the DHT, the service sends a @code{struct PeerPutMessage} | ||
7218 | of type @code{GNUNET_MESSAGE_TYPE_DHT_P2P_PUT} to the respective | ||
7219 | neighbour. | ||
7220 | In addition to the usual information about the content (type, routing | ||
7221 | options, desired replication level for the content, expiration time, key | ||
7222 | and value), the message contains a fixed-size Bloom filter with | ||
7223 | information about which peers (may) have already seen this request. | ||
7224 | This Bloom filter is used to ensure that DHT messages never loop back to | ||
7225 | a peer that has already processed the request. | ||
7226 | Additionally, the message includes the current hop counter and, depending | ||
7227 | on the routing options, the message may include the full path that the | ||
7228 | message has taken so far. | ||
7229 | The Bloom filter should already contain the identity of the previous hop; | ||
7230 | however, the path should not include the identity of the previous hop and | ||
7231 | the receiver should append the identity of the sender to the path, not | ||
7232 | its own identity (this is done to reduce bandwidth). | ||
7233 | |||
7234 | @node GETting data from the DHT2 | ||
7235 | @subsubsection GETting data from the DHT2 | ||
7236 | |||
7237 | @c %**end of header | ||
7238 | |||
7239 | A peer can search the DHT by sending @code{struct PeerGetMessage}s of type | ||
7240 | @code{GNUNET_MESSAGE_TYPE_DHT_P2P_GET} to other peers. In addition to the | ||
7241 | usual information about the request (type, routing options, desired | ||
7242 | replication level for the request, the key and the extended query), a GET | ||
7243 | request also again contains a hop counter, a Bloom filter over the peers | ||
7244 | that have processed the request already and depending on the routing | ||
7245 | options the full path traversed by the GET. | ||
7246 | Finally, a GET request includes a variable-size second Bloom filter and a | ||
7247 | so-called Bloom filter mutator value which together indicate which | ||
7248 | replies the sender has already seen. During the lookup, each block that | ||
7249 | matches they block type, key and extended query is additionally subjected | ||
7250 | to a test against this Bloom filter. | ||
7251 | The block plugin is expected to take the hash of the block and combine it | ||
7252 | with the mutator value and check if the result is not yet in the Bloom | ||
7253 | filter. The originator of the query will from time to time modify the | ||
7254 | mutator to (eventually) allow false-positives filtered by the Bloom filter | ||
7255 | to be returned. | ||
7256 | |||
7257 | Peers that receive a GET request perform a local lookup (depending on | ||
7258 | their proximity to the key and the query options) and forward the request | ||
7259 | to other peers. | ||
7260 | They then remember the request (including the Bloom filter for blocking | ||
7261 | duplicate results) and when they obtain a matching, non-filtered response | ||
7262 | a @code{struct PeerResultMessage} of type | ||
7263 | @code{GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT} is forwarded to the previous | ||
7264 | hop. | ||
7265 | Whenver a result is forwarded, the block plugin is used to update the | ||
7266 | Bloom filter accordingly, to ensure that the same result is never | ||
7267 | forwarded more than once. | ||
7268 | The DHT service may also cache forwarded results locally if the | ||
7269 | "CACHE_RESULTS" option is set to "YES" in the configuration. | ||
7270 | |||
7271 | @cindex GNS | ||
7272 | @cindex GNU Name System | ||
7273 | @node GNU Name System (GNS) | ||
7274 | @section GNU Name System (GNS) | ||
7275 | |||
7276 | @c %**end of header | ||
7277 | |||
7278 | The GNU Name System (GNS) is a decentralized database that enables users | ||
7279 | to securely resolve names to values. | ||
7280 | Names can be used to identify other users (for example, in social | ||
7281 | networking), or network services (for example, VPN services running at a | ||
7282 | peer in GNUnet, or purely IP-based services on the Internet). | ||
7283 | Users interact with GNS by typing in a hostname that ends in ".gnu" | ||
7284 | or ".zkey". | ||
7285 | |||
7286 | Videos giving an overview of most of the GNS and the motivations behind | ||
7287 | it is available here and here. | ||
7288 | The remainder of this chapter targets developers that are familiar with | ||
7289 | high level concepts of GNS as presented in these talks. | ||
7290 | @c TODO: Add links to here and here and to these. | ||
7291 | |||
7292 | GNS-aware applications should use the GNS resolver to obtain the | ||
7293 | respective records that are stored under that name in GNS. | ||
7294 | Each record consists of a type, value, expiration time and flags. | ||
7295 | |||
7296 | The type specifies the format of the value. Types below 65536 correspond | ||
7297 | to DNS record types, larger values are used for GNS-specific records. | ||
7298 | Applications can define new GNS record types by reserving a number and | ||
7299 | implementing a plugin (which mostly needs to convert the binary value | ||
7300 | representation to a human-readable text format and vice-versa). | ||
7301 | The expiration time specifies how long the record is to be valid. | ||
7302 | The GNS API ensures that applications are only given non-expired values. | ||
7303 | The flags are typically irrelevant for applications, as GNS uses them | ||
7304 | internally to control visibility and validity of records. | ||
7305 | |||
7306 | Records are stored along with a signature. | ||
7307 | The signature is generated using the private key of the authoritative | ||
7308 | zone. This allows any GNS resolver to verify the correctness of a | ||
7309 | name-value mapping. | ||
7310 | |||
7311 | Internally, GNS uses the NAMECACHE to cache information obtained from | ||
7312 | other users, the NAMESTORE to store information specific to the local | ||
7313 | users, and the DHT to exchange data between users. | ||
7314 | A plugin API is used to enable applications to define new GNS | ||
7315 | record types. | ||
7316 | |||
7317 | @menu | ||
7318 | * libgnunetgns:: | ||
7319 | * libgnunetgnsrecord:: | ||
7320 | * GNS plugins:: | ||
7321 | * The GNS Client-Service Protocol:: | ||
7322 | * Hijacking the DNS-Traffic using gnunet-service-dns:: | ||
7323 | * Serving DNS lookups via GNS on W32:: | ||
7324 | @end menu | ||
7325 | |||
7326 | @node libgnunetgns | ||
7327 | @subsection libgnunetgns | ||
7328 | |||
7329 | @c %**end of header | ||
7330 | |||
7331 | The GNS API itself is extremely simple. Clients first connec to the | ||
7332 | GNS service using @code{GNUNET_GNS_connect}. | ||
7333 | They can then perform lookups using @code{GNUNET_GNS_lookup} or cancel | ||
7334 | pending lookups using @code{GNUNET_GNS_lookup_cancel}. | ||
7335 | Once finished, clients disconnect using @code{GNUNET_GNS_disconnect}. | ||
7336 | |||
7337 | @menu | ||
7338 | * Looking up records:: | ||
7339 | * Accessing the records:: | ||
7340 | * Creating records:: | ||
7341 | * Future work:: | ||
7342 | @end menu | ||
7343 | |||
7344 | @node Looking up records | ||
7345 | @subsubsection Looking up records | ||
7346 | |||
7347 | @c %**end of header | ||
7348 | |||
7349 | @code{GNUNET_GNS_lookup} takes a number of arguments: | ||
7350 | |||
7351 | @table @asis | ||
7352 | @item handle This is simply the GNS connection handle from | ||
7353 | @code{GNUNET_GNS_connect}. | ||
7354 | @item name The client needs to specify the name to | ||
7355 | be resolved. This can be any valid DNS or GNS hostname. | ||
7356 | @item zone The client | ||
7357 | needs to specify the public key of the GNS zone against which the | ||
7358 | resolution should be done (the ".gnu" zone). | ||
7359 | Note that a key must be provided, even if the name ends in ".zkey". | ||
7360 | This should typically be the public key of the master-zone of the user. | ||
7361 | @item type This is the desired GNS or DNS record type | ||
7362 | to look for. While all records for the given name will be returned, this | ||
7363 | can be important if the client wants to resolve record types that | ||
7364 | themselves delegate resolution, such as CNAME, PKEY or GNS2DNS. | ||
7365 | Resolving a record of any of these types will only work if the respective | ||
7366 | record type is specified in the request, as the GNS resolver will | ||
7367 | otherwise follow the delegation and return the records from the | ||
7368 | respective destination, instead of the delegating record. | ||
7369 | @item only_cached This argument should typically be set to | ||
7370 | @code{GNUNET_NO}. Setting it to @code{GNUNET_YES} disables resolution via | ||
7371 | the overlay network. | ||
7372 | @item shorten_zone_key If GNS encounters new names during resolution, | ||
7373 | their respective zones can automatically be learned and added to the | ||
7374 | "shorten zone". If this is desired, clients must pass the private key of | ||
7375 | the shorten zone. If NULL is passed, shortening is disabled. | ||
7376 | @item proc This argument identifies | ||
7377 | the function to call with the result. It is given proc_cls, the number of | ||
7378 | records found (possilby zero) and the array of the records as arguments. | ||
7379 | proc will only be called once. After proc,> has been called, the lookup | ||
7380 | must no longer be cancelled. | ||
7381 | @item proc_cls The closure for proc. | ||
7382 | @end table | ||
7383 | |||
7384 | @node Accessing the records | ||
7385 | @subsubsection Accessing the records | ||
7386 | |||
7387 | @c %**end of header | ||
7388 | |||
7389 | The @code{libgnunetgnsrecord} library provides an API to manipulate the | ||
7390 | GNS record array that is given to proc. In particular, it offers | ||
7391 | functions such as converting record values to human-readable | ||
7392 | strings (and back). However, most @code{libgnunetgnsrecord} functions are | ||
7393 | not interesting to GNS client applications. | ||
7394 | |||
7395 | For DNS records, the @code{libgnunetdnsparser} library provides | ||
7396 | functions for parsing (and serializing) common types of DNS records. | ||
7397 | |||
7398 | @node Creating records | ||
7399 | @subsubsection Creating records | ||
7400 | |||
7401 | @c %**end of header | ||
7402 | |||
7403 | Creating GNS records is typically done by building the respective record | ||
7404 | information (possibly with the help of @code{libgnunetgnsrecord} and | ||
7405 | @code{libgnunetdnsparser}) and then using the @code{libgnunetnamestore} to | ||
7406 | publish the information. The GNS API is not involved in this | ||
7407 | operation. | ||
7408 | |||
7409 | @node Future work | ||
7410 | @subsubsection Future work | ||
7411 | |||
7412 | @c %**end of header | ||
7413 | |||
7414 | In the future, we want to expand @code{libgnunetgns} to allow | ||
7415 | applications to observe shortening operations performed during GNS | ||
7416 | resolution, for example so that users can receive visual feedback when | ||
7417 | this happens. | ||
7418 | |||
7419 | @node libgnunetgnsrecord | ||
7420 | @subsection libgnunetgnsrecord | ||
7421 | |||
7422 | @c %**end of header | ||
7423 | |||
7424 | The @code{libgnunetgnsrecord} library is used to manipulate GNS | ||
7425 | records (in plaintext or in their encrypted format). | ||
7426 | Applications mostly interact with @code{libgnunetgnsrecord} by using the | ||
7427 | functions to convert GNS record values to strings or vice-versa, or to | ||
7428 | lookup a GNS record type number by name (or vice-versa). | ||
7429 | The library also provides various other functions that are mostly | ||
7430 | used internally within GNS, such as converting keys to names, checking for | ||
7431 | expiration, encrypting GNS records to GNS blocks, verifying GNS block | ||
7432 | signatures and decrypting GNS records from GNS blocks. | ||
7433 | |||
7434 | We will now discuss the four commonly used functions of the API.@ | ||
7435 | @code{libgnunetgnsrecord} does not perform these operations itself, | ||
7436 | but instead uses plugins to perform the operation. | ||
7437 | GNUnet includes plugins to support common DNS record types as well as | ||
7438 | standard GNS record types. | ||
7439 | |||
7440 | @menu | ||
7441 | * Value handling:: | ||
7442 | * Type handling:: | ||
7443 | @end menu | ||
7444 | |||
7445 | @node Value handling | ||
7446 | @subsubsection Value handling | ||
7447 | |||
7448 | @c %**end of header | ||
7449 | |||
7450 | @code{GNUNET_GNSRECORD_value_to_string} can be used to convert | ||
7451 | the (binary) representation of a GNS record value to a human readable, | ||
7452 | 0-terminated UTF-8 string. | ||
7453 | NULL is returned if the specified record type is not supported by any | ||
7454 | available plugin. | ||
7455 | |||
7456 | @code{GNUNET_GNSRECORD_string_to_value} can be used to try to convert a | ||
7457 | human readable string to the respective (binary) representation of | ||
7458 | a GNS record value. | ||
7459 | |||
7460 | @node Type handling | ||
7461 | @subsubsection Type handling | ||
7462 | |||
7463 | @c %**end of header | ||
7464 | |||
7465 | @code{GNUNET_GNSRECORD_typename_to_number} can be used to obtain the | ||
7466 | numeric value associated with a given typename. For example, given the | ||
7467 | typename "A" (for DNS A reocrds), the function will return the number 1. | ||
7468 | A list of common DNS record types is | ||
7469 | @uref{http://en.wikipedia.org/wiki/List_of_DNS_record_types, here}. | ||
7470 | Note that not all DNS record types are supported by GNUnet GNSRECORD | ||
7471 | plugins at this time. | ||
7472 | |||
7473 | @code{GNUNET_GNSRECORD_number_to_typename} can be used to obtain the | ||
7474 | typename associated with a given numeric value. | ||
7475 | For example, given the type number 1, the function will return the | ||
7476 | typename "A". | ||
7477 | |||
7478 | @node GNS plugins | ||
7479 | @subsection GNS plugins | ||
7480 | |||
7481 | @c %**end of header | ||
7482 | |||
7483 | Adding a new GNS record type typically involves writing (or extending) a | ||
7484 | GNSRECORD plugin. The plugin needs to implement the | ||
7485 | @code{gnunet_gnsrecord_plugin.h} API which provides basic functions that | ||
7486 | are needed by GNSRECORD to convert typenames and values of the respective | ||
7487 | record type to strings (and back). | ||
7488 | These gnsrecord plugins are typically implemented within their respective | ||
7489 | subsystems. | ||
7490 | Examples for such plugins can be found in the GNSRECORD, GNS and | ||
7491 | CONVERSATION subsystems. | ||
7492 | |||
7493 | The @code{libgnunetgnsrecord} library is then used to locate, load and | ||
7494 | query the appropriate gnsrecord plugin. | ||
7495 | Which plugin is appropriate is determined by the record type (which is | ||
7496 | just a 32-bit integer). The @code{libgnunetgnsrecord} library loads all | ||
7497 | block plugins that are installed at the local peer and forwards the | ||
7498 | application request to the plugins. If the record type is not | ||
7499 | supported by the plugin, it should simply return an error code. | ||
7500 | |||
7501 | The central functions of the block APIs (plugin and main library) are the | ||
7502 | same four functions for converting between values and strings, and | ||
7503 | typenames and numbers documented in the previous subsection. | ||
7504 | |||
7505 | @node The GNS Client-Service Protocol | ||
7506 | @subsection The GNS Client-Service Protocol | ||
7507 | @c %**end of header | ||
7508 | |||
7509 | The GNS client-service protocol consists of two simple messages, the | ||
7510 | @code{LOOKUP} message and the @code{LOOKUP_RESULT}. Each @code{LOOKUP} | ||
7511 | message contains a unique 32-bit identifier, which will be included in the | ||
7512 | corresponding response. Thus, clients can send many lookup requests in | ||
7513 | parallel and receive responses out-of-order. | ||
7514 | A @code{LOOKUP} request also includes the public key of the GNS zone, | ||
7515 | the desired record type and fields specifying whether shortening is | ||
7516 | enabled or networking is disabled. Finally, the @code{LOOKUP} message | ||
7517 | includes the name to be resolved. | ||
7518 | |||
7519 | The response includes the number of records and the records themselves | ||
7520 | in the format created by @code{GNUNET_GNSRECORD_records_serialize}. | ||
7521 | They can thus be deserialized using | ||
7522 | @code{GNUNET_GNSRECORD_records_deserialize}. | ||
7523 | |||
7524 | @node Hijacking the DNS-Traffic using gnunet-service-dns | ||
7525 | @subsection Hijacking the DNS-Traffic using gnunet-service-dns | ||
7526 | |||
7527 | @c %**end of header | ||
7528 | |||
7529 | This section documents how the gnunet-service-dns (and the | ||
7530 | gnunet-helper-dns) intercepts DNS queries from the local system. | ||
7531 | This is merely one method for how we can obtain GNS queries. | ||
7532 | It is also possible to change @code{resolv.conf} to point to a machine | ||
7533 | running @code{gnunet-dns2gns} or to modify libc's name system switch | ||
7534 | (NSS) configuration to include a GNS resolution plugin. | ||
7535 | The method described in this chaper is more of a last-ditch catch-all | ||
7536 | approach. | ||
7537 | |||
7538 | @code{gnunet-service-dns} enables intercepting DNS traffic using policy | ||
7539 | based routing. | ||
7540 | We MARK every outgoing DNS-packet if it was not sent by our application. | ||
7541 | Using a second routing table in the Linux kernel these marked packets are | ||
7542 | then routed through our virtual network interface and can thus be | ||
7543 | captured unchanged. | ||
7544 | |||
7545 | Our application then reads the query and decides how to handle it: A | ||
7546 | query to an address ending in ".gnu" or ".zkey" is hijacked by | ||
7547 | @code{gnunet-service-gns} and resolved internally using GNS. | ||
7548 | In the future, a reverse query for an address of the configured virtual | ||
7549 | network could be answered with records kept about previous forward | ||
7550 | queries. | ||
7551 | Queries that are not hijacked by some application using the DNS service | ||
7552 | will be sent to the original recipient. | ||
7553 | The answer to the query will always be sent back through the virtual | ||
7554 | interface with the original nameserver as source address. | ||
7555 | |||
7556 | |||
7557 | @menu | ||
7558 | * Network Setup Details:: | ||
7559 | @end menu | ||
7560 | |||
7561 | @node Network Setup Details | ||
7562 | @subsubsection Network Setup Details | ||
7563 | |||
7564 | @c %**end of header | ||
7565 | |||
7566 | The DNS interceptor adds the following rules to the Linux kernel: | ||
7567 | @example | ||
7568 | iptables -t mangle -I OUTPUT 1 -p udp --sport $LOCALPORT --dport 53 \ | ||
7569 | -j ACCEPT iptables -t mangle -I OUTPUT 2 -p udp --dport 53 -j MARK \ | ||
7570 | --set-mark 3 ip rule add fwmark 3 table2 ip route add default via \ | ||
7571 | $VIRTUALDNS table2 | ||
7572 | @end example | ||
7573 | |||
7574 | @c FIXME: Rewrite to reflect display which is no longer content by line | ||
7575 | @c FIXME: due to the < 74 characters limit. | ||
7576 | Line 1 makes sure that all packets coming from a port our application | ||
7577 | opened beforehand (@code{$LOCALPORT}) will be routed normally. | ||
7578 | Line 2 marks every other packet to a DNS-Server with mark 3 (chosen | ||
7579 | arbitrarily). The third line adds a routing policy based on this mark | ||
7580 | 3 via the routing table. | ||
7581 | |||
7582 | @node Serving DNS lookups via GNS on W32 | ||
7583 | @subsection Serving DNS lookups via GNS on W32 | ||
7584 | |||
7585 | @c %**end of header | ||
7586 | |||
7587 | This section documents how the libw32nsp (and | ||
7588 | gnunet-gns-helper-service-w32) do DNS resolutions of DNS queries on the | ||
7589 | local system. This only applies to GNUnet running on W32. | ||
7590 | |||
7591 | W32 has a concept of "Namespaces" and "Namespace providers". | ||
7592 | These are used to present various name systems to applications in a | ||
7593 | generic way. | ||
7594 | Namespaces include DNS, mDNS, NLA and others. For each namespace any | ||
7595 | number of providers could be registered, and they are queried in an order | ||
7596 | of priority (which is adjustable). | ||
7597 | |||
7598 | Applications can resolve names by using WSALookupService*() family of | ||
7599 | functions. | ||
7600 | |||
7601 | However, these are WSA-only facilities. Common BSD socket functions for | ||
7602 | namespace resolutions are gethostbyname and getaddrinfo (among others). | ||
7603 | These functions are implemented internally (by default - by mswsock, | ||
7604 | which also implements the default DNS provider) as wrappers around | ||
7605 | WSALookupService*() functions (see "Sample Code for a Service Provider" | ||
7606 | on MSDN). | ||
7607 | |||
7608 | On W32 GNUnet builds a libw32nsp - a namespace provider, which can then be | ||
7609 | installed into the system by using w32nsp-install (and uninstalled by | ||
7610 | w32nsp-uninstall), as described in "Installation Handbook". | ||
7611 | |||
7612 | libw32nsp is very simple and has almost no dependencies. As a response to | ||
7613 | NSPLookupServiceBegin(), it only checks that the provider GUID passed to | ||
7614 | it by the caller matches GNUnet DNS Provider GUID, checks that name being | ||
7615 | resolved ends in ".gnu" or ".zkey", then connects to | ||
7616 | gnunet-gns-helper-service-w32 at 127.0.0.1:5353 (hardcoded) and sends the | ||
7617 | name resolution request there, returning the connected socket to the | ||
7618 | caller. | ||
7619 | |||
7620 | When the caller invokes NSPLookupServiceNext(), libw32nsp reads a | ||
7621 | completely formed reply from that socket, unmarshalls it, then gives | ||
7622 | it back to the caller. | ||
7623 | |||
7624 | At the moment gnunet-gns-helper-service-w32 is implemented to ever give | ||
7625 | only one reply, and subsequent calls to NSPLookupServiceNext() will fail | ||
7626 | with WSA_NODATA (first call to NSPLookupServiceNext() might also fail if | ||
7627 | GNS failed to find the name, or there was an error connecting to it). | ||
7628 | |||
7629 | gnunet-gns-helper-service-w32 does most of the processing: | ||
7630 | |||
7631 | @itemize @bullet | ||
7632 | @item Maintains a connection to GNS. | ||
7633 | @item Reads GNS config and loads appropriate keys. | ||
7634 | @item Checks service GUID and decides on the type of record to look up, | ||
7635 | refusing to make a lookup outright when unsupported service GUID is | ||
7636 | passed. | ||
7637 | @item Launches the lookup | ||
7638 | @end itemize | ||
7639 | |||
7640 | When lookup result arrives, gnunet-gns-helper-service-w32 forms a complete | ||
7641 | reply (including filling a WSAQUERYSETW structure and, possibly, a binary | ||
7642 | blob with a hostent structure for gethostbyname() client), marshalls it, | ||
7643 | and sends it back to libw32nsp. If no records were found, it sends an | ||
7644 | empty header. | ||
7645 | |||
7646 | This works for most normal applications that use gethostbyname() or | ||
7647 | getaddrinfo() to resolve names, but fails to do anything with | ||
7648 | applications that use alternative means of resolving names (such as | ||
7649 | sending queries to a DNS server directly by themselves). | ||
7650 | This includes some of well known utilities, like "ping" and "nslookup". | ||
7651 | |||
7652 | @cindex GNS Namecache | ||
7653 | @node GNS Namecache | ||
7654 | @section GNS Namecache | ||
7655 | |||
7656 | @c %**end of header | ||
7657 | |||
7658 | The NAMECACHE subsystem is responsible for caching (encrypted) resolution | ||
7659 | results of the GNU Name System (GNS). GNS makes zone information available | ||
7660 | to other users via the DHT. However, as accessing the DHT for every | ||
7661 | lookup is expensive (and as the DHT's local cache is lost whenever the | ||
7662 | peer is restarted), GNS uses the NAMECACHE as a more persistent cache for | ||
7663 | DHT lookups. | ||
7664 | Thus, instead of always looking up every name in the DHT, GNS first | ||
7665 | checks if the result is already available locally in the NAMECACHE. | ||
7666 | Only if there is no result in the NAMECACHE, GNS queries the DHT. | ||
7667 | The NAMECACHE stores data in the same (encrypted) format as the DHT. | ||
7668 | It thus makes no sense to iterate over all items in the | ||
7669 | NAMECACHE --- the NAMECACHE does not have a way to provide the keys | ||
7670 | required to decrypt the entries. | ||
7671 | |||
7672 | Blocks in the NAMECACHE share the same expiration mechanism as blocks in | ||
7673 | the DHT --- the block expires wheneever any of the records in | ||
7674 | the (encrypted) block expires. | ||
7675 | The expiration time of the block is the only information stored in | ||
7676 | plaintext. The NAMECACHE service internally performs all of the required | ||
7677 | work to expire blocks, clients do not have to worry about this. | ||
7678 | Also, given that NAMECACHE stores only GNS blocks that local users | ||
7679 | requested, there is no configuration option to limit the size of the | ||
7680 | NAMECACHE. It is assumed to be always small enough (a few MB) to fit on | ||
7681 | the drive. | ||
7682 | |||
7683 | The NAMECACHE supports the use of different database backends via a | ||
7684 | plugin API. | ||
7685 | |||
7686 | @menu | ||
7687 | * libgnunetnamecache:: | ||
7688 | * The NAMECACHE Client-Service Protocol:: | ||
7689 | * The NAMECACHE Plugin API:: | ||
7690 | @end menu | ||
7691 | |||
7692 | @node libgnunetnamecache | ||
7693 | @subsection libgnunetnamecache | ||
7694 | |||
7695 | @c %**end of header | ||
7696 | |||
7697 | The NAMECACHE API consists of five simple functions. First, there is | ||
7698 | @code{GNUNET_NAMECACHE_connect} to connect to the NAMECACHE service. | ||
7699 | This returns the handle required for all other operations on the | ||
7700 | NAMECACHE. Using @code{GNUNET_NAMECACHE_block_cache} clients can insert a | ||
7701 | block into the cache. | ||
7702 | @code{GNUNET_NAMECACHE_lookup_block} can be used to lookup blocks that | ||
7703 | were stored in the NAMECACHE. Both operations can be cancelled using | ||
7704 | @code{GNUNET_NAMECACHE_cancel}. Note that cancelling a | ||
7705 | @code{GNUNET_NAMECACHE_block_cache} operation can result in the block | ||
7706 | being stored in the NAMECACHE --- or not. Cancellation primarily ensures | ||
7707 | that the continuation function with the result of the operation will no | ||
7708 | longer be invoked. | ||
7709 | Finally, @code{GNUNET_NAMECACHE_disconnect} closes the connection to the | ||
7710 | NAMECACHE. | ||
7711 | |||
7712 | The maximum size of a block that can be stored in the NAMECACHE is | ||
7713 | @code{GNUNET_NAMECACHE_MAX_VALUE_SIZE}, which is defined to be 63 kB. | ||
7714 | |||
7715 | @node The NAMECACHE Client-Service Protocol | ||
7716 | @subsection The NAMECACHE Client-Service Protocol | ||
7717 | |||
7718 | @c %**end of header | ||
7719 | |||
7720 | All messages in the NAMECACHE IPC protocol start with the | ||
7721 | @code{struct GNUNET_NAMECACHE_Header} which adds a request | ||
7722 | ID (32-bit integer) to the standard message header. | ||
7723 | The request ID is used to match requests with the | ||
7724 | respective responses from the NAMECACHE, as they are allowed to happen | ||
7725 | out-of-order. | ||
7726 | |||
7727 | |||
7728 | @menu | ||
7729 | * Lookup:: | ||
7730 | * Store:: | ||
7731 | @end menu | ||
7732 | |||
7733 | @node Lookup | ||
7734 | @subsubsection Lookup | ||
7735 | |||
7736 | @c %**end of header | ||
7737 | |||
7738 | The @code{struct LookupBlockMessage} is used to lookup a block stored in | ||
7739 | the cache. | ||
7740 | It contains the query hash. The NAMECACHE always responds with a | ||
7741 | @code{struct LookupBlockResponseMessage}. If the NAMECACHE has no | ||
7742 | response, it sets the expiration time in the response to zero. | ||
7743 | Otherwise, the response is expected to contain the expiration time, the | ||
7744 | ECDSA signature, the derived key and the (variable-size) encrypted data | ||
7745 | of the block. | ||
7746 | |||
7747 | @node Store | ||
7748 | @subsubsection Store | ||
7749 | |||
7750 | @c %**end of header | ||
7751 | |||
7752 | The @code{struct BlockCacheMessage} is used to cache a block in the | ||
7753 | NAMECACHE. | ||
7754 | It has the same structure as the @code{struct LookupBlockResponseMessage}. | ||
7755 | The service responds with a @code{struct BlockCacheResponseMessage} which | ||
7756 | contains the result of the operation (success or failure). | ||
7757 | In the future, we might want to make it possible to provide an error | ||
7758 | message as well. | ||
7759 | |||
7760 | @node The NAMECACHE Plugin API | ||
7761 | @subsection The NAMECACHE Plugin API | ||
7762 | @c %**end of header | ||
7763 | |||
7764 | The NAMECACHE plugin API consists of two functions, @code{cache_block} to | ||
7765 | store a block in the database, and @code{lookup_block} to lookup a block | ||
7766 | in the database. | ||
7767 | |||
7768 | |||
7769 | @menu | ||
7770 | * Lookup2:: | ||
7771 | * Store2:: | ||
7772 | @end menu | ||
7773 | |||
7774 | @node Lookup2 | ||
7775 | @subsubsection Lookup2 | ||
7776 | |||
7777 | @c %**end of header | ||
7778 | |||
7779 | The @code{lookup_block} function is expected to return at most one block | ||
7780 | to the iterator, and return @code{GNUNET_NO} if there were no non-expired | ||
7781 | results. | ||
7782 | If there are multiple non-expired results in the cache, the lookup is | ||
7783 | supposed to return the result with the largest expiration time. | ||
7784 | |||
7785 | @node Store2 | ||
7786 | @subsubsection Store2 | ||
7787 | |||
7788 | @c %**end of header | ||
7789 | |||
7790 | The @code{cache_block} function is expected to try to store the block in | ||
7791 | the database, and return @code{GNUNET_SYSERR} if this was not possible | ||
7792 | for any reason. | ||
7793 | Furthermore, @code{cache_block} is expected to implicitly perform cache | ||
7794 | maintenance and purge blocks from the cache that have expired. Note that | ||
7795 | @code{cache_block} might encounter the case where the database already has | ||
7796 | another block stored under the same key. In this case, the plugin must | ||
7797 | ensure that the block with the larger expiration time is preserved. | ||
7798 | Obviously, this can done either by simply adding new blocks and selecting | ||
7799 | for the most recent expiration time during lookup, or by checking which | ||
7800 | block is more recent during the store operation. | ||
7801 | |||
7802 | @cindex REVOCATION Subsystem | ||
7803 | @node REVOCATION Subsystem | ||
7804 | @section REVOCATION Subsystem | ||
7805 | @c %**end of header | ||
7806 | |||
7807 | The REVOCATION subsystem is responsible for key revocation of Egos. | ||
7808 | If a user learns that theis private key has been compromised or has lost | ||
7809 | it, they can use the REVOCATION system to inform all of the other users | ||
7810 | that their private key is no longer valid. | ||
7811 | The subsystem thus includes ways to query for the validity of keys and to | ||
7812 | propagate revocation messages. | ||
7813 | |||
7814 | @menu | ||
7815 | * Dissemination:: | ||
7816 | * Revocation Message Design Requirements:: | ||
7817 | * libgnunetrevocation:: | ||
7818 | * The REVOCATION Client-Service Protocol:: | ||
7819 | * The REVOCATION Peer-to-Peer Protocol:: | ||
7820 | @end menu | ||
7821 | |||
7822 | @node Dissemination | ||
7823 | @subsection Dissemination | ||
7824 | |||
7825 | @c %**end of header | ||
7826 | |||
7827 | When a revocation is performed, the revocation is first of all | ||
7828 | disseminated by flooding the overlay network. | ||
7829 | The goal is to reach every peer, so that when a peer needs to check if a | ||
7830 | key has been revoked, this will be purely a local operation where the | ||
7831 | peer looks at his local revocation list. Flooding the network is also the | ||
7832 | most robust form of key revocation --- an adversary would have to control | ||
7833 | a separator of the overlay graph to restrict the propagation of the | ||
7834 | revocation message. Flooding is also very easy to implement --- peers that | ||
7835 | receive a revocation message for a key that they have never seen before | ||
7836 | simply pass the message to all of their neighbours. | ||
7837 | |||
7838 | Flooding can only distribute the revocation message to peers that are | ||
7839 | online. | ||
7840 | In order to notify peers that join the network later, the revocation | ||
7841 | service performs efficient set reconciliation over the sets of known | ||
7842 | revocation messages whenever two peers (that both support REVOCATION | ||
7843 | dissemination) connect. | ||
7844 | The SET service is used to perform this operation efficiently. | ||
7845 | |||
7846 | @node Revocation Message Design Requirements | ||
7847 | @subsection Revocation Message Design Requirements | ||
7848 | |||
7849 | @c %**end of header | ||
7850 | |||
7851 | However, flooding is also quite costly, creating O(|E|) messages on a | ||
7852 | network with |E| edges. | ||
7853 | Thus, revocation messages are required to contain a proof-of-work, the | ||
7854 | result of an expensive computation (which, however, is cheap to verify). | ||
7855 | Only peers that have expended the CPU time necessary to provide | ||
7856 | this proof will be able to flood the network with the revocation message. | ||
7857 | This ensures that an attacker cannot simply flood the network with | ||
7858 | millions of revocation messages. The proof-of-work required by GNUnet is | ||
7859 | set to take days on a typical PC to compute; if the ability to quickly | ||
7860 | revoke a key is needed, users have the option to pre-compute revocation | ||
7861 | messages to store off-line and use instantly after their key has expired. | ||
7862 | |||
7863 | Revocation messages must also be signed by the private key that is being | ||
7864 | revoked. Thus, they can only be created while the private key is in the | ||
7865 | possession of the respective user. This is another reason to create a | ||
7866 | revocation message ahead of time and store it in a secure location. | ||
7867 | |||
7868 | @node libgnunetrevocation | ||
7869 | @subsection libgnunetrevocation | ||
7870 | |||
7871 | @c %**end of header | ||
7872 | |||
7873 | The REVOCATION API consists of two parts, to query and to issue | ||
7874 | revocations. | ||
7875 | |||
7876 | |||
7877 | @menu | ||
7878 | * Querying for revoked keys:: | ||
7879 | * Preparing revocations:: | ||
7880 | * Issuing revocations:: | ||
7881 | @end menu | ||
7882 | |||
7883 | @node Querying for revoked keys | ||
7884 | @subsubsection Querying for revoked keys | ||
7885 | |||
7886 | @c %**end of header | ||
7887 | |||
7888 | @code{GNUNET_REVOCATION_query} is used to check if a given ECDSA public | ||
7889 | key has been revoked. | ||
7890 | The given callback will be invoked with the result of the check. | ||
7891 | The query can be cancelled using @code{GNUNET_REVOCATION_query_cancel} on | ||
7892 | the return value. | ||
7893 | |||
7894 | @node Preparing revocations | ||
7895 | @subsubsection Preparing revocations | ||
7896 | |||
7897 | @c %**end of header | ||
7898 | |||
7899 | It is often desirable to create a revocation record ahead-of-time and | ||
7900 | store it in an off-line location to be used later in an emergency. | ||
7901 | This is particularly true for GNUnet revocations, where performing the | ||
7902 | revocation operation itself is computationally expensive and thus is | ||
7903 | likely to take some time. | ||
7904 | Thus, if users want the ability to perform revocations quickly in an | ||
7905 | emergency, they must pre-compute the revocation message. | ||
7906 | The revocation API enables this with two functions that are used to | ||
7907 | compute the revocation message, but not trigger the actual revocation | ||
7908 | operation. | ||
7909 | |||
7910 | @code{GNUNET_REVOCATION_check_pow} should be used to calculate the | ||
7911 | proof-of-work required in the revocation message. This function takes the | ||
7912 | public key, the required number of bits for the proof of work (which in | ||
7913 | GNUnet is a network-wide constant) and finally a proof-of-work number as | ||
7914 | arguments. | ||
7915 | The function then checks if the given proof-of-work number is a valid | ||
7916 | proof of work for the given public key. Clients preparing a revocation | ||
7917 | are expected to call this function repeatedly (typically with a | ||
7918 | monotonically increasing sequence of numbers of the proof-of-work number) | ||
7919 | until a given number satisfies the check. | ||
7920 | That number should then be saved for later use in the revocation | ||
7921 | operation. | ||
7922 | |||
7923 | @code{GNUNET_REVOCATION_sign_revocation} is used to generate the | ||
7924 | signature that is required in a revocation message. | ||
7925 | It takes the private key that (possibly in the future) is to be revoked | ||
7926 | and returns the signature. | ||
7927 | The signature can again be saved to disk for later use, which will then | ||
7928 | allow performing a revocation even without access to the private key. | ||
7929 | |||
7930 | @node Issuing revocations | ||
7931 | @subsubsection Issuing revocations | ||
7932 | |||
7933 | |||
7934 | Given a ECDSA public key, the signature from @code{GNUNET_REVOCATION_sign} | ||
7935 | and the proof-of-work, | ||
7936 | @code{GNUNET_REVOCATION_revoke} can be used to perform the | ||
7937 | actual revocation. The given callback is called upon completion of the | ||
7938 | operation. @code{GNUNET_REVOCATION_revoke_cancel} can be used to stop the | ||
7939 | library from calling the continuation; however, in that case it is | ||
7940 | undefined whether or not the revocation operation will be executed. | ||
7941 | |||
7942 | @node The REVOCATION Client-Service Protocol | ||
7943 | @subsection The REVOCATION Client-Service Protocol | ||
7944 | |||
7945 | |||
7946 | The REVOCATION protocol consists of four simple messages. | ||
7947 | |||
7948 | A @code{QueryMessage} containing a public ECDSA key is used to check if a | ||
7949 | particular key has been revoked. The service responds with a | ||
7950 | @code{QueryResponseMessage} which simply contains a bit that says if the | ||
7951 | given public key is still valid, or if it has been revoked. | ||
7952 | |||
7953 | The second possible interaction is for a client to revoke a key by | ||
7954 | passing a @code{RevokeMessage} to the service. The @code{RevokeMessage} | ||
7955 | contains the ECDSA public key to be revoked, a signature by the | ||
7956 | corresponding private key and the proof-of-work, The service responds | ||
7957 | with a @code{RevocationResponseMessage} which can be used to indicate | ||
7958 | that the @code{RevokeMessage} was invalid (i.e. proof of work incorrect), | ||
7959 | or otherwise indicates that the revocation has been processed | ||
7960 | successfully. | ||
7961 | |||
7962 | @node The REVOCATION Peer-to-Peer Protocol | ||
7963 | @subsection The REVOCATION Peer-to-Peer Protocol | ||
7964 | |||
7965 | @c %**end of header | ||
7966 | |||
7967 | Revocation uses two disjoint ways to spread revocation information among | ||
7968 | peers. | ||
7969 | First of all, P2P gossip exchanged via CORE-level neighbours is used to | ||
7970 | quickly spread revocations to all connected peers. | ||
7971 | Second, whenever two peers (that both support revocations) connect, | ||
7972 | the SET service is used to compute the union of the respective revocation | ||
7973 | sets. | ||
7974 | |||
7975 | In both cases, the exchanged messages are @code{RevokeMessage}s which | ||
7976 | contain the public key that is being revoked, a matching ECDSA signature, | ||
7977 | and a proof-of-work. | ||
7978 | Whenever a peer learns about a new revocation this way, it first | ||
7979 | validates the signature and the proof-of-work, then stores it to disk | ||
7980 | (typically to a file $GNUNET_DATA_HOME/revocation.dat) and finally | ||
7981 | spreads the information to all directly connected neighbours. | ||
7982 | |||
7983 | For computing the union using the SET service, the peer with the smaller | ||
7984 | hashed peer identity will connect (as a "client" in the two-party set | ||
7985 | protocol) to the other peer after one second (to reduce traffic spikes | ||
7986 | on connect) and initiate the computation of the set union. | ||
7987 | All revocation services use a common hash to identify the SET operation | ||
7988 | over revocation sets. | ||
7989 | |||
7990 | The current implementation accepts revocation set union operations from | ||
7991 | all peers at any time; however, well-behaved peers should only initiate | ||
7992 | this operation once after establishing a connection to a peer with a | ||
7993 | larger hashed peer identity. | ||
7994 | |||
7995 | @cindex FS | ||
7996 | @cindex FS Subsystem | ||
7997 | @node File-sharing (FS) Subsystem | ||
7998 | @section File-sharing (FS) Subsystem | ||
7999 | |||
8000 | @c %**end of header | ||
8001 | |||
8002 | This chapter describes the details of how the file-sharing service works. | ||
8003 | As with all services, it is split into an API (libgnunetfs), the service | ||
8004 | process (gnunet-service-fs) and user interface(s). | ||
8005 | The file-sharing service uses the datastore service to store blocks and | ||
8006 | the DHT (and indirectly datacache) for lookups for non-anonymous | ||
8007 | file-sharing. | ||
8008 | Furthermore, the file-sharing service uses the block library (and the | ||
8009 | block fs plugin) for validation of DHT operations. | ||
8010 | |||
8011 | In contrast to many other services, libgnunetfs is rather complex since | ||
8012 | the client library includes a large number of high-level abstractions; | ||
8013 | this is necessary since the Fs service itself largely only operates on | ||
8014 | the block level. | ||
8015 | The FS library is responsible for providing a file-based abstraction to | ||
8016 | applications, including directories, meta data, keyword search, | ||
8017 | verification, and so on. | ||
8018 | |||
8019 | The method used by GNUnet to break large files into blocks and to use | ||
8020 | keyword search is called the | ||
8021 | "Encoding for Censorship Resistant Sharing" (ECRS). | ||
8022 | ECRS is largely implemented in the fs library; block validation is also | ||
8023 | reflected in the block FS plugin and the FS service. | ||
8024 | ECRS on-demand encoding is implemented in the FS service. | ||
8025 | |||
8026 | NOTE: The documentation in this chapter is quite incomplete. | ||
8027 | |||
8028 | @menu | ||
8029 | * Encoding for Censorship-Resistant Sharing (ECRS):: | ||
8030 | * File-sharing persistence directory structure:: | ||
8031 | @end menu | ||
8032 | |||
8033 | @cindex ECRS | ||
8034 | @cindex Encoding for Censorship-Resistant Sharing | ||
8035 | @node Encoding for Censorship-Resistant Sharing (ECRS) | ||
8036 | @subsection Encoding for Censorship-Resistant Sharing (ECRS) | ||
8037 | |||
8038 | @c %**end of header | ||
8039 | |||
8040 | When GNUnet shares files, it uses a content encoding that is called ECRS, | ||
8041 | the Encoding for Censorship-Resistant Sharing. | ||
8042 | Most of ECRS is described in the (so far unpublished) research paper | ||
8043 | attached to this page. ECRS obsoletes the previous ESED and ESED II | ||
8044 | encodings which were used in GNUnet before version 0.7.0. | ||
8045 | The rest of this page assumes that the reader is familiar with the | ||
8046 | attached paper. What follows is a description of some minor extensions | ||
8047 | that GNUnet makes over what is described in the paper. | ||
8048 | The reason why these extensions are not in the paper is that we felt | ||
8049 | that they were obvious or trivial extensions to the original scheme and | ||
8050 | thus did not warrant space in the research report. | ||
8051 | |||
8052 | @menu | ||
8053 | * Namespace Advertisements:: | ||
8054 | * KSBlocks:: | ||
8055 | @end menu | ||
8056 | |||
8057 | @node Namespace Advertisements | ||
8058 | @subsubsection Namespace Advertisements | ||
8059 | |||
8060 | @c %**end of header | ||
8061 | @c %**FIXME: all zeroses -> ? | ||
8062 | |||
8063 | An @code{SBlock} with identifier all zeros is a signed | ||
8064 | advertisement for a namespace. This special @code{SBlock} contains | ||
8065 | metadata describing the content of the namespace. | ||
8066 | Instead of the name of the identifier for a potential update, it contains | ||
8067 | the identifier for the root of the namespace. | ||
8068 | The URI should always be empty. The @code{SBlock} is signed with the | ||
8069 | content provder's RSA private key (just like any other SBlock). Peers | ||
8070 | can search for @code{SBlock}s in order to find out more about a namespace. | ||
8071 | |||
8072 | @node KSBlocks | ||
8073 | @subsubsection KSBlocks | ||
8074 | |||
8075 | @c %**end of header | ||
8076 | |||
8077 | GNUnet implements @code{KSBlocks} which are @code{KBlocks} that, instead | ||
8078 | of encrypting a CHK and metadata, encrypt an @code{SBlock} instead. | ||
8079 | In other words, @code{KSBlocks} enable GNUnet to find @code{SBlocks} | ||
8080 | using the global keyword search. | ||
8081 | Usually the encrypted @code{SBlock} is a namespace advertisement. | ||
8082 | The rationale behind @code{KSBlock}s and @code{SBlock}s is to enable | ||
8083 | peers to discover namespaces via keyword searches, and, to associate | ||
8084 | useful information with namespaces. When GNUnet finds @code{KSBlocks} | ||
8085 | during a normal keyword search, it adds the information to an internal | ||
8086 | list of discovered namespaces. Users looking for interesting namespaces | ||
8087 | can then inspect this list, reducing the need for out-of-band discovery | ||
8088 | of namespaces. | ||
8089 | Naturally, namespaces (or more specifically, namespace advertisements) can | ||
8090 | also be referenced from directories, but @code{KSBlock}s should make it | ||
8091 | easier to advertise namespaces for the owner of the pseudonym since they | ||
8092 | eliminate the need to first create a directory. | ||
8093 | |||
8094 | Collections are also advertised using @code{KSBlock}s. | ||
8095 | |||
8096 | @table @asis | ||
8097 | @item Attachment Size | ||
8098 | @item ecrs.pdf 270.68 KB | ||
8099 | @item https://gnunet.org/sites/default/files/ecrs.pdf | ||
8100 | @end table | ||
8101 | |||
8102 | @node File-sharing persistence directory structure | ||
8103 | @subsection File-sharing persistence directory structure | ||
8104 | |||
8105 | @c %**end of header | ||
8106 | |||
8107 | This section documents how the file-sharing library implements | ||
8108 | persistence of file-sharing operations and specifically the resulting | ||
8109 | directory structure. | ||
8110 | This code is only active if the @code{GNUNET_FS_FLAGS_PERSISTENCE} flag | ||
8111 | was set when calling @code{GNUNET_FS_start}. | ||
8112 | In this case, the file-sharing library will try hard to ensure that all | ||
8113 | major operations (searching, downloading, publishing, unindexing) are | ||
8114 | persistent, that is, can live longer than the process itself. | ||
8115 | More specifically, an operation is supposed to live until it is | ||
8116 | explicitly stopped. | ||
8117 | |||
8118 | If @code{GNUNET_FS_stop} is called before an operation has been stopped, a | ||
8119 | @code{SUSPEND} event is generated and then when the process calls | ||
8120 | @code{GNUNET_FS_start} next time, a @code{RESUME} event is generated. | ||
8121 | Additionally, even if an application crashes (segfault, SIGKILL, system | ||
8122 | crash) and hence @code{GNUNET_FS_stop} is never called and no | ||
8123 | @code{SUSPEND} events are generated, operations are still resumed (with | ||
8124 | @code{RESUME} events). | ||
8125 | This is implemented by constantly writing the current state of the | ||
8126 | file-sharing operations to disk. | ||
8127 | Specifically, the current state is always written to disk whenever | ||
8128 | anything significant changes (the exception are block-wise progress in | ||
8129 | publishing and unindexing, since those operations would be slowed down | ||
8130 | significantly and can be resumed cheaply even without detailed | ||
8131 | accounting). | ||
8132 | Note that if the process crashes (or is killed) during a serialization | ||
8133 | operation, FS does not guarantee that this specific operation is | ||
8134 | recoverable (no strict transactional semantics, again for performance | ||
8135 | reasons). However, all other unrelated operations should resume nicely. | ||
8136 | |||
8137 | Since we need to serialize the state continuously and want to recover as | ||
8138 | much as possible even after crashing during a serialization operation, | ||
8139 | we do not use one large file for serialization. | ||
8140 | Instead, several directories are used for the various operations. | ||
8141 | When @code{GNUNET_FS_start} executes, the master directories are scanned | ||
8142 | for files describing operations to resume. | ||
8143 | Sometimes, these operations can refer to related operations in child | ||
8144 | directories which may also be resumed at this point. | ||
8145 | Note that corrupted files are cleaned up automatically. | ||
8146 | However, dangling files in child directories (those that are not | ||
8147 | referenced by files from the master directories) are not automatically | ||
8148 | removed. | ||
8149 | |||
8150 | Persistence data is kept in a directory that begins with the "STATE_DIR" | ||
8151 | prefix from the configuration file | ||
8152 | (by default, "$SERVICEHOME/persistence/") followed by the name of the | ||
8153 | client as given to @code{GNUNET_FS_start} (for example, "gnunet-gtk") | ||
8154 | followed by the actual name of the master or child directory. | ||
8155 | |||
8156 | The names for the master directories follow the names of the operations: | ||
8157 | |||
8158 | @itemize @bullet | ||
8159 | @item "search" | ||
8160 | @item "download" | ||
8161 | @item "publish" | ||
8162 | @item "unindex" | ||
8163 | @end itemize | ||
8164 | |||
8165 | Each of the master directories contains names (chosen at random) for each | ||
8166 | active top-level (master) operation. | ||
8167 | Note that a download that is associated with a search result is not a | ||
8168 | top-level operation. | ||
8169 | |||
8170 | In contrast to the master directories, the child directories are only | ||
8171 | consulted when another operation refers to them. | ||
8172 | For each search, a subdirectory (named after the master search | ||
8173 | synchronization file) contains the search results. | ||
8174 | Search results can have an associated download, which is then stored in | ||
8175 | the general "download-child" directory. | ||
8176 | Downloads can be recursive, in which case children are stored in | ||
8177 | subdirectories mirroring the structure of the recursive download | ||
8178 | (either starting in the master "download" directory or in the | ||
8179 | "download-child" directory depending on how the download was initiated). | ||
8180 | For publishing operations, the "publish-file" directory contains | ||
8181 | information about the individual files and directories that are part of | ||
8182 | the publication. | ||
8183 | However, this directory structure is flat and does not mirror the | ||
8184 | structure of the publishing operation. | ||
8185 | Note that unindex operations cannot have associated child operations. | ||
8186 | |||
8187 | @cindex REGEX subsystem | ||
8188 | @node REGEX Subsystem | ||
8189 | @section REGEX Subsystem | ||
8190 | |||
8191 | @c %**end of header | ||
8192 | |||
8193 | Using the REGEX subsystem, you can discover peers that offer a particular | ||
8194 | service using regular expressions. | ||
8195 | The peers that offer a service specify it using a regular expressions. | ||
8196 | Peers that want to patronize a service search using a string. | ||
8197 | The REGEX subsystem will then use the DHT to return a set of matching | ||
8198 | offerers to the patrons. | ||
8199 | |||
8200 | For the technical details, we have Max's defense talk and Max's Master's | ||
8201 | thesis. | ||
8202 | |||
8203 | @c An additional publication is under preparation and available to | ||
8204 | @c team members (in Git). | ||
8205 | @c FIXME: Where is the file? Point to it. Assuming that it's szengel2012ms | ||
8206 | |||
8207 | @menu | ||
8208 | * How to run the regex profiler:: | ||
8209 | @end menu | ||
8210 | |||
8211 | @node How to run the regex profiler | ||
8212 | @subsection How to run the regex profiler | ||
8213 | |||
8214 | @c %**end of header | ||
8215 | |||
8216 | The gnunet-regex-profiler can be used to profile the usage of mesh/regex | ||
8217 | for a given set of regular expressions and strings. | ||
8218 | Mesh/regex allows you to announce your peer ID under a certain regex and | ||
8219 | search for peers matching a particular regex using a string. | ||
8220 | See @uref{https://gnunet.org/szengel2012ms, szengel2012ms} for a full | ||
8221 | introduction. | ||
8222 | |||
8223 | First of all, the regex profiler uses GNUnet testbed, thus all the | ||
8224 | implications for testbed also apply to the regex profiler | ||
8225 | (for example you need password-less ssh login to the machines listed in | ||
8226 | your hosts file). | ||
8227 | |||
8228 | @strong{Configuration} | ||
8229 | |||
8230 | Moreover, an appropriate configuration file is needed. | ||
8231 | Generally you can refer to the | ||
8232 | @file{contrib/regex_profiler_infiniband.conf} file in the sourcecode | ||
8233 | of GNUnet for an example configuration. | ||
8234 | In the following paragraph the important details are highlighted. | ||
8235 | |||
8236 | Announcing of the regular expressions is done by the | ||
8237 | gnunet-daemon-regexprofiler, therefore you have to make sure it is | ||
8238 | started, by adding it to the AUTOSTART set of ARM: | ||
8239 | |||
8240 | @example | ||
8241 | [regexprofiler] | ||
8242 | AUTOSTART = YES | ||
8243 | @end example | ||
8244 | |||
8245 | @noindent | ||
8246 | Furthermore you have to specify the location of the binary: | ||
8247 | |||
8248 | @example | ||
8249 | [regexprofiler] | ||
8250 | # Location of the gnunet-daemon-regexprofiler binary. | ||
8251 | BINARY = /home/szengel/gnunet/src/mesh/.libs/gnunet-daemon-regexprofiler | ||
8252 | # Regex prefix that will be applied to all regular expressions and | ||
8253 | # search string. | ||
8254 | REGEX_PREFIX = "GNVPN-0001-PAD" | ||
8255 | @end example | ||
8256 | |||
8257 | @noindent | ||
8258 | When running the profiler with a large scale deployment, you probably | ||
8259 | want to reduce the workload of each peer. | ||
8260 | Use the following options to do this. | ||
8261 | |||
8262 | @example | ||
8263 | [dht] | ||
8264 | # Force network size estimation | ||
8265 | FORCE_NSE = 1 | ||
8266 | |||
8267 | [dhtcache] | ||
8268 | DATABASE = heap | ||
8269 | # Disable RC-file for Bloom filter? (for benchmarking with limited IO | ||
8270 | # availability) | ||
8271 | DISABLE_BF_RC = YES | ||
8272 | # Disable Bloom filter entirely | ||
8273 | DISABLE_BF = YES | ||
8274 | |||
8275 | [nse] | ||
8276 | # Minimize proof-of-work CPU consumption by NSE | ||
8277 | WORKBITS = 1 | ||
8278 | @end example | ||
8279 | |||
8280 | @noindent | ||
8281 | @strong{Options} | ||
8282 | |||
8283 | To finally run the profiler some options and the input data need to be | ||
8284 | specified on the command line. | ||
8285 | |||
8286 | @example | ||
8287 | gnunet-regex-profiler -c config-file -d log-file -n num-links \ | ||
8288 | -p path-compression-length -s search-delay -t matching-timeout \ | ||
8289 | -a num-search-strings hosts-file policy-dir search-strings-file | ||
8290 | @end example | ||
8291 | |||
8292 | @noindent | ||
8293 | Where... | ||
8294 | |||
8295 | @itemize @bullet | ||
8296 | @item ... @code{config-file} means the configuration file created earlier. | ||
8297 | @item ... @code{log-file} is the file where to write statistics output. | ||
8298 | @item ... @code{num-links} indicates the number of random links between | ||
8299 | started peers. | ||
8300 | @item ... @code{path-compression-length} is the maximum path compression | ||
8301 | length in the DFA. | ||
8302 | @item ... @code{search-delay} time to wait between peers finished linking | ||
8303 | and starting to match strings. | ||
8304 | @item ... @code{matching-timeout} timeout after which to cancel the | ||
8305 | searching. | ||
8306 | @item ... @code{num-search-strings} number of strings in the | ||
8307 | search-strings-file. | ||
8308 | @item ... the @code{hosts-file} should contain a list of hosts for the | ||
8309 | testbed, one per line in the following format: | ||
8310 | |||
8311 | @itemize @bullet | ||
8312 | @item @code{user@@host_ip:port} | ||
8313 | @end itemize | ||
8314 | @item ... the @code{policy-dir} is a folder containing text files | ||
8315 | containing one or more regular expressions. A peer is started for each | ||
8316 | file in that folder and the regular expressions in the corresponding file | ||
8317 | are announced by this peer. | ||
8318 | @item ... the @code{search-strings-file} is a text file containing search | ||
8319 | strings, one in each line. | ||
8320 | @end itemize | ||
8321 | |||
8322 | @noindent | ||
8323 | You can create regular expressions and search strings for every AS in the | ||
8324 | Internet using the attached scripts. You need one of the | ||
8325 | @uref{http://data.caida.org/datasets/routing/routeviews-prefix2as/, CAIDA routeviews prefix2as} | ||
8326 | data files for this. Run | ||
8327 | |||
8328 | @example | ||
8329 | create_regex.py <filename> <output path> | ||
8330 | @end example | ||
8331 | |||
8332 | @noindent | ||
8333 | to create the regular expressions and | ||
8334 | |||
8335 | @example | ||
8336 | create_strings.py <input path> <outfile> | ||
8337 | @end example | ||
8338 | |||
8339 | @noindent | ||
8340 | to create a search strings file from the previously created | ||
8341 | regular expressions. | ||
diff --git a/doc/documentation/chapters/installation.texi b/doc/documentation/chapters/installation.texi new file mode 100644 index 000000000..eca77afcd --- /dev/null +++ b/doc/documentation/chapters/installation.texi | |||
@@ -0,0 +1,4123 @@ | |||
1 | @node GNUnet Installation Handbook | ||
2 | @chapter GNUnet Installation Handbook | ||
3 | |||
4 | This handbook describes how to install (build, setup, compile) and | ||
5 | setup (configure, start) GNUnet @value{VERSION}. After following these | ||
6 | instructions you should be able to install and then start user-interfaces | ||
7 | to interact with the network. | ||
8 | |||
9 | Note: This manual is far from complete, and we welcome informed | ||
10 | contributions, be it in the form of new chapters or insightful comments. | ||
11 | |||
12 | @menu | ||
13 | * Dependencies:: | ||
14 | * Pre-installation notes:: | ||
15 | * Generic installation instructions:: | ||
16 | * Build instructions for Ubuntu 12.04 using Git:: | ||
17 | * Build instructions for software builds from source:: | ||
18 | * Build Instructions for Microsoft Windows Platforms:: | ||
19 | * Build instructions for Debian 7.5:: | ||
20 | * Installing GNUnet from Git on Ubuntu 14.4:: | ||
21 | * Build instructions for Debian 8:: | ||
22 | * Outdated build instructions for previous revisions:: | ||
23 | @c * Portable GNUnet:: | ||
24 | * The graphical configuration interface:: | ||
25 | * How to start and stop a GNUnet peer:: | ||
26 | @end menu | ||
27 | |||
28 | @node Dependencies | ||
29 | @section Dependencies | ||
30 | @c %**end of header | ||
31 | |||
32 | This section lists the various known dependencies for | ||
33 | GNUnet @value{EDITION}. | ||
34 | Suggestions for missing dependencies or wrong version numbers are welcome. | ||
35 | |||
36 | @menu | ||
37 | * External dependencies:: | ||
38 | * Optional dependencies:: | ||
39 | * Internal dependencies:: | ||
40 | @end menu | ||
41 | |||
42 | @node External dependencies | ||
43 | @subsection External dependencies | ||
44 | @c %**end of header | ||
45 | |||
46 | These packages must be installed before a typical GNUnet installation | ||
47 | can be performed: | ||
48 | |||
49 | @itemize @bullet | ||
50 | @item autoconf | ||
51 | @item automake | ||
52 | @item pkg-config | ||
53 | @item libltdl | ||
54 | @item gstreamer | ||
55 | @item gst-plugins-base | ||
56 | @item perl | ||
57 | @item python (only 2.7 supported)@footnote{tests and gnunet-qr} | ||
58 | @item jansson | ||
59 | @item nss | ||
60 | @item glib | ||
61 | @item gmp | ||
62 | @item bluez | ||
63 | @item miniupnpc | ||
64 | @item gettext | ||
65 | @item which | ||
66 | @item texinfo @geq{} 5.2 | ||
67 | @item GNU libmicrohttpd @geq{} 0.9.30 @footnote{We recommend to build it | ||
68 | with a GnuTLS version that was configured with libunbound} | ||
69 | @item GNU libextractor @geq{} 1.0 | ||
70 | @item GNU libtool @geq{} 2.2 | ||
71 | @item GNU libunistring @geq{} 0.9.1.1 | ||
72 | @item GNU libidn @geq{} 1.0.0 | ||
73 | @item @uref{https://gnupg.org/software/libgcrypt/, GNU libgcrypt} @geq{} | ||
74 | @uref{https://gnupg.org/ftp/gcrypt/libgcrypt/, 1.6.0} | ||
75 | @item @uref{https://gnutls.org/, GnuTLS} @geq{} 3.2.7 | ||
76 | @footnote{We recommend to compile with libunbound for DANE support; | ||
77 | GnuTLS also requires GNU nettle 2.7 (update: GnuTLS 3.2.7 appears NOT | ||
78 | to work against GNU nettle > 2.7, due to some API updatings done by | ||
79 | nettle. Thus it should be compiled against nettle 2.7 | ||
80 | and, in case you get some error on the reference to `rpl_strerror' being | ||
81 | undefined, follow the instructions on | ||
82 | @uref{http://lists.gnupg.org/pipermail/gnutls-devel/2013-November/006588.html, this} | ||
83 | post (and the link inside it)).} | ||
84 | @item @uref{https://gnunet.org/gnurl, gnURL} libgnurl @geq{} 7.34.0 | ||
85 | @footnote{must be compiled after @code{GnuTLS}} | ||
86 | @item libglpk @geq{} 4.45 | ||
87 | @item @uref{http://www.openssl.org/, OpenSSL} @geq{} 1.0 | ||
88 | @item TeX Live @geq{} 2012, optional (for gnunet-bcd) | ||
89 | @item Texinfo @geq{} 5.2 (for documentation) | ||
90 | @item libsqlite @geq{} 3.8.0 @footnote{(note that the code will | ||
91 | compile and often work with lower version numbers, but you may get subtle | ||
92 | bugs with respect to quota management in certain rare cases); | ||
93 | alternatively, MySQL or Postgres can also be installed, but those | ||
94 | databases will require more complex configurations (not | ||
95 | recommended for first-time users)} | ||
96 | @item zlib | ||
97 | @end itemize | ||
98 | |||
99 | @node Optional dependencies | ||
100 | @subsection Optional dependencies | ||
101 | |||
102 | These applications must be installed for various experimental or otherwise | ||
103 | optional features such as @command{gnunet-conversation}, | ||
104 | and @command{gnunet-gtk} (most of these features are only build if you | ||
105 | configure GNUnet with @command{--enable-experimental}): | ||
106 | |||
107 | @itemize @bullet | ||
108 | @item libpulse @geq{} 2.0, | ||
109 | optional (for @command{gnunet-conversation}) | ||
110 | @item libopus @geq{} 1.0.1, | ||
111 | optional (for @command{gnunet-conversation}) | ||
112 | @item libogg @geq{} 1.3.0, | ||
113 | optional (for @command{gnunet-conversation}) | ||
114 | @item libnss contained @command{certool} binary, | ||
115 | optional for convenient installation of | ||
116 | the GNS proxy. | ||
117 | @item python-zbar @geq{} 0.10, | ||
118 | optional (for @command{gnunet-qr}) | ||
119 | @item Gtk+ @geq{} 3.0, | ||
120 | optional (for @command{gnunet-gtk}) | ||
121 | @item libgladeui (must match Gtk+ version), | ||
122 | optional (for @command{gnunet-gtk}) | ||
123 | @item libqrencode @geq{} 3.0, | ||
124 | optional (for @command{gnunet-namestore-gtk}) | ||
125 | @end itemize | ||
126 | |||
127 | @node Internal dependencies | ||
128 | @subsection Internal dependencies | ||
129 | |||
130 | This section tries to give an overview of what processes a typical GNUnet | ||
131 | peer running a particular application would consist of. All of the | ||
132 | processes listed here should be automatically started by | ||
133 | @command{gnunet-arm -s}. | ||
134 | The list is given as a rough first guide to users for failure diagnostics. | ||
135 | Ideally, end-users should never have to worry about these internal | ||
136 | dependencies. | ||
137 | |||
138 | In terms of internal dependencies, a minimum file-sharing system consists | ||
139 | of the following GNUnet processes (in order of dependency): | ||
140 | |||
141 | @itemize @bullet | ||
142 | @item gnunet-service-arm | ||
143 | @item gnunet-service-resolver (required by all) | ||
144 | @item gnunet-service-statistics (required by all) | ||
145 | @item gnunet-service-peerinfo | ||
146 | @item gnunet-service-transport (requires peerinfo) | ||
147 | @item gnunet-service-core (requires transport) | ||
148 | @item gnunet-daemon-hostlist (requires core) | ||
149 | @item gnunet-daemon-topology (requires hostlist, peerinfo) | ||
150 | @item gnunet-service-datastore | ||
151 | @item gnunet-service-dht (requires core) | ||
152 | @item gnunet-service-identity | ||
153 | @item gnunet-service-fs (requires identity, mesh, dht, datastore, core) | ||
154 | @end itemize | ||
155 | |||
156 | @noindent | ||
157 | A minimum VPN system consists of the following GNUnet processes (in | ||
158 | order of dependency): | ||
159 | |||
160 | @itemize @bullet | ||
161 | @item gnunet-service-arm | ||
162 | @item gnunet-service-resolver (required by all) | ||
163 | @item gnunet-service-statistics (required by all) | ||
164 | @item gnunet-service-peerinfo | ||
165 | @item gnunet-service-transport (requires peerinfo) | ||
166 | @item gnunet-service-core (requires transport) | ||
167 | @item gnunet-daemon-hostlist (requires core) | ||
168 | @item gnunet-service-dht (requires core) | ||
169 | @item gnunet-service-mesh (requires dht, core) | ||
170 | @item gnunet-service-dns (requires dht) | ||
171 | @item gnunet-service-regex (requires dht) | ||
172 | @item gnunet-service-vpn (requires regex, dns, mesh, dht) | ||
173 | @end itemize | ||
174 | |||
175 | @noindent | ||
176 | A minimum GNS system consists of the following GNUnet processes (in | ||
177 | order of dependency): | ||
178 | |||
179 | @itemize @bullet | ||
180 | @item gnunet-service-arm | ||
181 | @item gnunet-service-resolver (required by all) | ||
182 | @item gnunet-service-statistics (required by all) | ||
183 | @item gnunet-service-peerinfo | ||
184 | @item gnunet-service-transport (requires peerinfo) | ||
185 | @item gnunet-service-core (requires transport) | ||
186 | @item gnunet-daemon-hostlist (requires core) | ||
187 | @item gnunet-service-dht (requires core) | ||
188 | @item gnunet-service-mesh (requires dht, core) | ||
189 | @item gnunet-service-dns (requires dht) | ||
190 | @item gnunet-service-regex (requires dht) | ||
191 | @item gnunet-service-vpn (requires regex, dns, mesh, dht) | ||
192 | @item gnunet-service-identity | ||
193 | @item gnunet-service-namestore (requires identity) | ||
194 | @item gnunet-service-gns (requires vpn, dns, dht, namestore, identity) | ||
195 | @end itemize | ||
196 | |||
197 | @node Pre-installation notes | ||
198 | @section Pre-installation notes | ||
199 | |||
200 | Please note that in the code instructions for the installation, | ||
201 | @emph{#} indicates commands run as privileged root user and | ||
202 | @emph{$} shows commands run as unprivileged ("normal") system user. | ||
203 | |||
204 | |||
205 | @node Generic installation instructions | ||
206 | @section Generic installation instructions | ||
207 | |||
208 | First, in addition to the GNUnet sources you might require downloading the | ||
209 | latest version of various dependencies, depending on how recent the | ||
210 | software versions in your distribution of GNU/Linux are. | ||
211 | Most distributions do not include sufficiently recent versions of these | ||
212 | dependencies. | ||
213 | Thus, a typically installation on a "modern" GNU/Linux distribution | ||
214 | requires you to install the following dependencies (ideally in this | ||
215 | order): | ||
216 | |||
217 | @itemize @bullet | ||
218 | @item libgpgerror and libgcrypt | ||
219 | @item libnettle and libunbound (possibly from distribution), GnuTLS | ||
220 | @item libgnurl (read the README) | ||
221 | @item GNU libmicrohttpd | ||
222 | @item GNU libextractor | ||
223 | @end itemize | ||
224 | |||
225 | Make sure to first install the various mandatory and optional | ||
226 | dependencies including development headers from your distribution. | ||
227 | |||
228 | Other dependencies that you should strongly consider to install is a | ||
229 | database (MySQL, sqlite or Postgres). | ||
230 | The following instructions will assume that you installed at least sqlite. | ||
231 | For most distributions you should be able to find pre-build packages for | ||
232 | the database. Again, make sure to install the client libraries @b{and} the | ||
233 | respective development headers (if they are packaged separately) as well. | ||
234 | |||
235 | You can find specific, detailed instructions for installing of the | ||
236 | dependencies (and possibly the rest of the GNUnet installation) in the | ||
237 | platform-specific descriptions, which can be found in the Index. | ||
238 | Please consult them now. | ||
239 | If your distribution is not listed, please study | ||
240 | @ref{Build instructions for Debian 8}, the build instructions for | ||
241 | Debian stable, carefully as you try to install the dependencies for your | ||
242 | own distribution. | ||
243 | Contributing additional instructions for further platforms is always | ||
244 | appreciated. | ||
245 | Please take in mind that operating system development tends to move at | ||
246 | a rather fast speed. Due to this you should be aware that some of | ||
247 | the instructions could be outdated by the time you are reading this. | ||
248 | If you find a mistake, please tell us about it (or even better: send | ||
249 | a patch to the documentation to fix it!). | ||
250 | |||
251 | Before proceeding further, please double-check the dependency list. | ||
252 | Note that in addition to satisfying the dependencies, you might have to | ||
253 | make sure that development headers for the various libraries are also | ||
254 | installed. | ||
255 | There maybe files for other distributions, or you might be able to find | ||
256 | equivalent packages for your distribution. | ||
257 | |||
258 | While it is possible to build and install GNUnet without having root | ||
259 | access, we will assume that you have full control over your system in | ||
260 | these instructions. | ||
261 | First, you should create a system user @emph{gnunet} and an additional | ||
262 | group @emph{gnunetdns}. On the GNU/Linux distributions Debian and Ubuntu, | ||
263 | type: | ||
264 | |||
265 | @example | ||
266 | # adduser --system --home /var/lib/gnunet --group \ | ||
267 | --disabled-password gnunet | ||
268 | # addgroup --system gnunetdns | ||
269 | @end example | ||
270 | |||
271 | @noindent | ||
272 | On other Unixes and GNU systems, this should have the same effect: | ||
273 | |||
274 | @example | ||
275 | # useradd --system --groups gnunet --home-dir /var/lib/gnunet | ||
276 | # addgroup --system gnunetdns | ||
277 | @end example | ||
278 | |||
279 | Now compile and install GNUnet using: | ||
280 | |||
281 | @example | ||
282 | $ tar xvf gnunet-@value{VERSION}.tar.gz | ||
283 | $ cd gnunet-@value{VERSION} | ||
284 | $ ./configure --with-sudo=sudo --with-nssdir=/lib | ||
285 | $ make | ||
286 | $ sudo make install | ||
287 | @end example | ||
288 | |||
289 | If you want to be able to enable DEBUG-level log messages, add | ||
290 | @code{--enable-logging=verbose} to the end of the | ||
291 | @command{./configure} command. | ||
292 | @code{DEBUG}-level log messages are in English only and | ||
293 | should only be useful for developers (or for filing | ||
294 | really detailed bug reports). | ||
295 | |||
296 | Finally, you probably want to compile @command{gnunet-gtk}, which | ||
297 | includes @command{gnunet-setup} (a graphical tool for | ||
298 | GNUnet configuration) and @command{gnunet-fs-gtk} (a graphical tool for | ||
299 | GNUnet file-sharing): | ||
300 | |||
301 | @example | ||
302 | $ tar xvf gnunet-gtk-@value{VERSION}.tar.gz | ||
303 | $ cd gnunet-gtk-@value{VERSION} | ||
304 | $ ./configure --with-gnunet=/usr/local/ | ||
305 | $ make | ||
306 | $ sudo make install | ||
307 | $ cd .. | ||
308 | # just to be safe run this: | ||
309 | $ sudo ldconfig | ||
310 | @end example | ||
311 | |||
312 | @noindent | ||
313 | Next, edit the file @file{/etc/gnunet.conf} to contain the following: | ||
314 | |||
315 | @example | ||
316 | [arm] | ||
317 | SYSTEM_ONLY = YES | ||
318 | USER_ONLY = NO | ||
319 | @end example | ||
320 | |||
321 | @noindent | ||
322 | You may need to update your @code{ld.so} cache to include | ||
323 | files installed in @file{/usr/local/lib}: | ||
324 | |||
325 | @example | ||
326 | # ldconfig | ||
327 | @end example | ||
328 | |||
329 | @noindent | ||
330 | Then, switch from user @code{root} to user @code{gnunet} to start | ||
331 | the peer: | ||
332 | |||
333 | @example | ||
334 | # su -s /bin/sh - gnunet | ||
335 | $ gnunet-arm -c /etc/gnunet.conf -s | ||
336 | @end example | ||
337 | |||
338 | You may also want to add the last line in the gnunet user's @file{crontab} | ||
339 | prefixed with @code{@@reboot} so that it is executed whenever the system | ||
340 | is booted: | ||
341 | |||
342 | @example | ||
343 | @@reboot /usr/local/bin/gnunet-arm -c /etc/gnunet.conf -s | ||
344 | @end example | ||
345 | |||
346 | @noindent | ||
347 | This will only start the system-wide GNUnet services. | ||
348 | Type exit to get back your root shell. | ||
349 | Now, you need to configure the per-user part. For each | ||
350 | $USER that should get access to GNUnet on the system, run: | ||
351 | |||
352 | @example | ||
353 | # adduser $USER gnunet | ||
354 | @end example | ||
355 | |||
356 | @noindent | ||
357 | to allow them to access the system-wide GNUnet services. Then, each | ||
358 | user should create a configuration file @file{~/.config/gnunet.conf} | ||
359 | with the lines: | ||
360 | |||
361 | @example | ||
362 | [arm] | ||
363 | SYSTEM_ONLY = NO | ||
364 | USER_ONLY = YES | ||
365 | DEFAULTSERVICES = gns | ||
366 | @end example | ||
367 | |||
368 | @noindent | ||
369 | and start the per-user services using | ||
370 | |||
371 | @example | ||
372 | $ gnunet-arm -c ~/.config/gnunet.conf -s | ||
373 | @end example | ||
374 | |||
375 | @noindent | ||
376 | Again, adding a @code{crontab} entry to autostart the peer is advised: | ||
377 | |||
378 | @example | ||
379 | @@reboot /usr/local/bin/gnunet-arm -c $HOME/.config/gnunet.conf -s | ||
380 | @end example | ||
381 | |||
382 | @noindent | ||
383 | Note that some GNUnet services (such as SOCKS5 proxies) may need a | ||
384 | system-wide TCP port for each user. | ||
385 | For those services, systems with more than one user may require each user | ||
386 | to specify a different port number in their personal configuration file. | ||
387 | |||
388 | Finally, the user should perform the basic initial setup for the GNU Name | ||
389 | System (GNS). This is done by running two commands: | ||
390 | |||
391 | @example | ||
392 | $ gnunet-gns-import.sh | ||
393 | $ gnunet-gns-proxy-setup-ca | ||
394 | @end example | ||
395 | |||
396 | @noindent | ||
397 | The first generates the default zones, wheras the second setups the GNS | ||
398 | Certificate Authority with the user's browser. Now, to activate GNS in the | ||
399 | normal DNS resolution process, you need to edit your | ||
400 | @file{/etc/nsswitch.conf} where you should find a line like this: | ||
401 | |||
402 | @example | ||
403 | hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4 | ||
404 | @end example | ||
405 | |||
406 | @noindent | ||
407 | The exact details may differ a bit, which is fine. Add the text | ||
408 | @emph{"gns [NOTFOUND=return]"} after @emph{"files"}. | ||
409 | Keep in mind that we included a backslash ("\") here just for | ||
410 | markup reasons. You should write the text below on @b{one line} | ||
411 | and @b{without} the "\": | ||
412 | |||
413 | @example | ||
414 | hosts: files gns [NOTFOUND=return] mdns4_minimal \ | ||
415 | [NOTFOUND=return] dns mdns4 | ||
416 | @end example | ||
417 | |||
418 | @c FIXME: Document new behavior. | ||
419 | You might want to make sure that @file{/lib/libnss_gns.so.2} exists on | ||
420 | your system, it should have been created during the installation. | ||
421 | |||
422 | @node Build instructions for Ubuntu 12.04 using Git | ||
423 | @section Build instructions for Ubuntu 12.04 using Git | ||
424 | |||
425 | @menu | ||
426 | * Install the required build tools:: | ||
427 | * Install libgcrypt 1.6 and libgpg-error:: | ||
428 | * Install gnutls with DANE support:: | ||
429 | * Install libgnurl:: | ||
430 | * Install libmicrohttpd from Git:: | ||
431 | * Install libextractor from Git:: | ||
432 | * Install GNUnet dependencies:: | ||
433 | * Build GNUnet:: | ||
434 | * Install the GNUnet-gtk user interface from Git:: | ||
435 | @end menu | ||
436 | |||
437 | @node Install the required build tools | ||
438 | @subsection Install the required build tools | ||
439 | |||
440 | First, make sure Git is installed on your system: | ||
441 | |||
442 | @example | ||
443 | $ sudo apt-get install git | ||
444 | @end example | ||
445 | |||
446 | Install the essential buildtools: | ||
447 | |||
448 | @example | ||
449 | $ sudo apt-get install automake autopoint autoconf libtool | ||
450 | @end example | ||
451 | |||
452 | @node Install libgcrypt 1.6 and libgpg-error | ||
453 | @subsection Install libgcrypt 1.6 and libgpg-error | ||
454 | |||
455 | @ref{generic source installation - libgpg-error} | ||
456 | |||
457 | @node Install gnutls with DANE support | ||
458 | @subsection Install gnutls with DANE support | ||
459 | |||
460 | @itemize @bullet | ||
461 | @item @ref{generic source installation - nettle} | ||
462 | @item @ref{generic source installation - ldns} | ||
463 | @item @ref{generic source installation - libunbound/unbound} | ||
464 | @item @ref{generic source installation - gnutls} | ||
465 | @item @ref{generic source installation - libgcrypt} | ||
466 | @end itemize | ||
467 | |||
468 | @node Install libgnurl | ||
469 | @subsection Install libgnurl | ||
470 | |||
471 | Follow the @ref{generic source installation - libgnurl}. | ||
472 | |||
473 | @node Install libmicrohttpd from Git | ||
474 | @subsection Install libmicrohttpd from Git | ||
475 | |||
476 | @example | ||
477 | $ git clone https://gnunet.org/git/libmicrohttpd | ||
478 | $ cd libmicrohttpd/ | ||
479 | $ ./bootstrap | ||
480 | $ ./configure | ||
481 | $ sudo make install ; cd .. | ||
482 | @end example | ||
483 | |||
484 | @node Install libextractor from Git | ||
485 | @subsection Install libextractor from Git | ||
486 | |||
487 | Install libextractor dependencies: | ||
488 | |||
489 | @example | ||
490 | $ sudo apt-get install zlib1g-dev libgsf-1-dev libmpeg2-4-dev \ | ||
491 | libpoppler-dev libvorbis-dev libexiv2-dev libjpeg-dev \ | ||
492 | libtiff-dev libgif-dev libvorbis-dev libflac-dev libsmf-dev \ | ||
493 | g++ | ||
494 | @end example | ||
495 | |||
496 | Build libextractor: | ||
497 | |||
498 | @example | ||
499 | $ git clone https://gnunet.org/git/libextractor | ||
500 | $ cd libextractor | ||
501 | $ ./bootstrap | ||
502 | $ ./configure | ||
503 | $ sudo make install ; cd .. | ||
504 | @end example | ||
505 | |||
506 | @node Install GNUnet dependencies | ||
507 | @subsection Install GNUnet dependencies | ||
508 | |||
509 | @example | ||
510 | $ sudo apt-get install libidn11-dev libunistring-dev libglpk-dev \ | ||
511 | libpulse-dev libbluetooth-dev libsqlite-dev | ||
512 | @end example | ||
513 | |||
514 | Install libopus: | ||
515 | |||
516 | @example | ||
517 | $ wget http://downloads.xiph.org/releases/opus/opus-1.1.tar.gz | ||
518 | $ tar xf opus-1.1.tar.gz | ||
519 | $ cd opus-1.1/ | ||
520 | $ ./configure | ||
521 | $ sudo make install ; cd .. | ||
522 | @end example | ||
523 | |||
524 | Choose one or more database backends: | ||
525 | |||
526 | SQLite3: | ||
527 | @example | ||
528 | $ sudo apt-get install libsqlite3-dev | ||
529 | @end example | ||
530 | MySQL: | ||
531 | @example | ||
532 | $ sudo apt-get install libmysqlclient-dev | ||
533 | @end example | ||
534 | PostgreSQL: | ||
535 | @example | ||
536 | $ sudo apt-get install libpq-dev postgresql | ||
537 | @end example | ||
538 | |||
539 | |||
540 | |||
541 | @node Build GNUnet | ||
542 | @subsection Build GNUnet | ||
543 | |||
544 | |||
545 | |||
546 | @menu | ||
547 | * Configuring the installation path:: | ||
548 | * Configuring the system:: | ||
549 | * Installing components requiring sudo permission:: | ||
550 | * Build:: | ||
551 | @end menu | ||
552 | |||
553 | @node Configuring the installation path | ||
554 | @subsubsection Configuring the installation path | ||
555 | |||
556 | You can specify the location of the GNUnet installation by setting the | ||
557 | prefix when calling the configure script with @code{--prefix=DIRECTORY} | ||
558 | |||
559 | @example | ||
560 | $ export PATH=$PATH:DIRECTORY/bin | ||
561 | @end example | ||
562 | |||
563 | @node Configuring the system | ||
564 | @subsubsection Configuring the system | ||
565 | |||
566 | Please make sure NOW that you have created a user and group 'gnunet' | ||
567 | and additionally a group 'gnunetdns': | ||
568 | |||
569 | @example | ||
570 | $ sudo addgroup gnunet | ||
571 | $ sudo addgroup gnunetdns | ||
572 | $ sudo adduser gnunet | ||
573 | @end example | ||
574 | |||
575 | Each GNUnet user should be added to the 'gnunet' group (may | ||
576 | require fresh login to come into effect): | ||
577 | |||
578 | @example | ||
579 | $ sudo useradd -G gnunet | ||
580 | @end example | ||
581 | |||
582 | @node Installing components requiring sudo permission | ||
583 | @subsubsection Installing components requiring sudo permission | ||
584 | |||
585 | Some components, like the nss plugin required for GNS, may require root | ||
586 | permissions. To allow these few components to be installed use: | ||
587 | |||
588 | @example | ||
589 | $ ./configure --with-sudo | ||
590 | @end example | ||
591 | |||
592 | @node Build | ||
593 | @subsubsection Build | ||
594 | |||
595 | @example | ||
596 | $ git clone https://gnunet.org/git/gnunet/ | ||
597 | $ cd gnunet/ | ||
598 | $ ./bootstrap | ||
599 | @end example | ||
600 | |||
601 | Use the required configure call including the optional installation prefix | ||
602 | @code{PREFIX} or the sudo permissions: | ||
603 | |||
604 | @example | ||
605 | $ ./configure [ --with-sudo | --with-prefix=PREFIX ] | ||
606 | @end example | ||
607 | |||
608 | @example | ||
609 | $ make; sudo make install | ||
610 | @end example | ||
611 | |||
612 | After installing it, you need to create an empty configuration file: | ||
613 | |||
614 | @example | ||
615 | mkdir ~/.gnunet; touch ~/.gnunet/gnunet.conf | ||
616 | @end example | ||
617 | |||
618 | And finally you can start GNUnet with: | ||
619 | |||
620 | @example | ||
621 | $ gnunet-arm -s | ||
622 | @end example | ||
623 | |||
624 | @node Install the GNUnet-gtk user interface from Git | ||
625 | @subsection Install the GNUnet-gtk user interface from Git | ||
626 | |||
627 | |||
628 | Install depencies: | ||
629 | |||
630 | @example | ||
631 | $ sudo apt-get install libgtk-3-dev libunique-3.0-dev libgladeui-dev \ | ||
632 | libqrencode-dev | ||
633 | @end example | ||
634 | |||
635 | Build GNUnet (with an optional prefix) and execute: | ||
636 | |||
637 | @example | ||
638 | $ git clone https://gnunet.org/git/gnunet-gtk/ | ||
639 | $ cd gnunet-gtk/ | ||
640 | $ ./bootstrap | ||
641 | $ ./configure [--prefix=PREFIX] --with-gnunet=DIRECTORY | ||
642 | $ make; sudo make install | ||
643 | @end example | ||
644 | |||
645 | @node Build instructions for software builds from source | ||
646 | @section Build instructions for software builds from source | ||
647 | |||
648 | This section describes software builds in case your operating | ||
649 | system lacks binary substitutes / binary builds for some dependencies | ||
650 | of GNUnet. | ||
651 | It is assumed that you have installed common build dependencies | ||
652 | and that these instructions are treated as generic without any | ||
653 | debugging help. | ||
654 | It is furthermore assumed that you use the release tarballs of | ||
655 | the software, installation from the respective version control | ||
656 | sources might differ in ways that are only minimal different | ||
657 | (for example a dependency on autotools etc). | ||
658 | |||
659 | @menu | ||
660 | * generic source installation - nettle:: | ||
661 | * generic source installation - ldns:: | ||
662 | * generic source installation - libunbound/unbound:: | ||
663 | * generic source installation - libav:: | ||
664 | * generic source installation - libextractor:: | ||
665 | * generic source installation - libgpg-error:: | ||
666 | * generic source installation - libgcrypt:: | ||
667 | * generic source installation - gnutls:: | ||
668 | * generic source installation - libmicrohttpd:: | ||
669 | * generic source installation - libgnurl:: | ||
670 | @end menu | ||
671 | |||
672 | @node generic source installation - nettle | ||
673 | @subsection generic source installation - nettle | ||
674 | |||
675 | @example | ||
676 | $ wget http://www.lysator.liu.se/~nisse/archive/nettle-2.7.1.tar.gz | ||
677 | $ tar xf nettle-2.7.1.tar.gz | ||
678 | $ cd nettle-2.7.1 | ||
679 | $ ./configure | ||
680 | $ sudo make install ; cd .. | ||
681 | @end example | ||
682 | |||
683 | @node generic source installation - ldns | ||
684 | @subsection generic source installation - ldns | ||
685 | |||
686 | @example | ||
687 | $ wget https://www.nlnetlabs.nl/downloads/ldns/ldns-1.6.16.tar.gz | ||
688 | $ tar xf ldns-1.6.16.tar.gz | ||
689 | $ cd ldns-1.6.16 | ||
690 | $ ./configure | ||
691 | $ sudo make install ; cd .. | ||
692 | @end example | ||
693 | |||
694 | @node generic source installation - libunbound/unbound | ||
695 | @subsection generic source installation - libunbound/unbound | ||
696 | |||
697 | @example | ||
698 | $ wget https://unbound.net/downloads/unbound-1.4.21.tar.gz | ||
699 | $ tar xf unbound-1.4.21.tar.gz | ||
700 | $ cd unbound-1.4.21 | ||
701 | $ ./configure | ||
702 | $ sudo make install ; cd .. | ||
703 | @end example | ||
704 | |||
705 | @node generic source installation - libav | ||
706 | @subsection generic source installation - libav | ||
707 | |||
708 | @example | ||
709 | $ wget https://libav.org/releases/libav-9.10.tar.xz | ||
710 | $ cd libav-0.9 ; ./configure --enable-shared; | ||
711 | $ make; sudo make install; cd .. | ||
712 | @end example | ||
713 | |||
714 | @node generic source installation - libextractor | ||
715 | @subsection generic source installation - libextractor | ||
716 | |||
717 | @example | ||
718 | $ wget https://ftp.gnu.org/gnu/libextractor/libextractor-1.3.tar.gz | ||
719 | $ tar xvf libextractor-1.3.tar.gz | ||
720 | $ cd libextractor-1.3 ; ./configure; | ||
721 | $ make ; sudo make install; cd .. | ||
722 | @end example | ||
723 | |||
724 | @node generic source installation - libgpg-error | ||
725 | @subsection generic source installation - libgpg-error | ||
726 | |||
727 | @example | ||
728 | $ wget https://ftp.gnupg.org/gcrypt/libgpg-error/libgpg-error-1.12.tar.bz2 | ||
729 | $ tar xvf libgpg-error-1.12.tar.bz2 | ||
730 | $ cd libgpg-error-1.12; ./configure; | ||
731 | $ make ; sudo make install; cd .. | ||
732 | @end example | ||
733 | |||
734 | @node generic source installation - libgcrypt | ||
735 | @subsection generic source installation - libgcrypt | ||
736 | @example | ||
737 | $ wget https://ftp.gnupg.org/gcrypt/libgcrypt/libgcrypt-1.6.0.tar.bz2 | ||
738 | $ tar xvf libgcrypt-1.6.0.tar.bz2 | ||
739 | $ cd libgcrypt-1.6.0; ./configure --with-gpg-error-prefix=/usr/local; | ||
740 | $ make ; sudo make install ; cd .. | ||
741 | @end example | ||
742 | |||
743 | @node generic source installation - gnutls | ||
744 | @subsection generic source installation - gnutls | ||
745 | |||
746 | @example | ||
747 | $ wget ftp://ftp.gnutls.org/gcrypt/gnutls/v3.2/gnutls-3.2.7.tar.xz | ||
748 | $ tar xvf gnutls-3.2.7.tar.xz | ||
749 | $ cd gnutls-3.2.7 | ||
750 | @end example | ||
751 | |||
752 | @noindent | ||
753 | If you want a GnuTLS with DANE functionality (recommended for GNUnet), | ||
754 | you have to compile it against libunbound. Assuming that libunbound | ||
755 | is installed on your system: | ||
756 | |||
757 | @example | ||
758 | $ ./configure --enable-libdane | ||
759 | @end example | ||
760 | |||
761 | @noindent | ||
762 | Note that the build system of GnuTLS should pick up libunbound without | ||
763 | the explicit mention of @code{--enable-libdane}. | ||
764 | If you don't want libdane support you should pass @code{--disable-libdane} | ||
765 | instead. | ||
766 | |||
767 | @example | ||
768 | $ ./configure | ||
769 | $ make ; sudo make install ; cd .. | ||
770 | @end example | ||
771 | |||
772 | @node generic source installation - libmicrohttpd | ||
773 | @subsection generic source installation - libmicrohttpd | ||
774 | |||
775 | @example | ||
776 | $ wget https://ftp.gnu.org/gnu/libmicrohttpd/libmicrohttpd-0.9.33.tar.gz | ||
777 | $ tar xvf libmicrohttpd-0.9.33.tar.gz | ||
778 | $ cd libmicrohttpd-0.9.33; ./configure; | ||
779 | $ make ; sudo make install ; cd .. | ||
780 | @end example | ||
781 | |||
782 | @node generic source installation - libgnurl | ||
783 | @subsection generic source installation - libgnurl | ||
784 | |||
785 | Example installation of libgnurl version 7.57.0 from source. | ||
786 | |||
787 | @example | ||
788 | $ wget https://ftp.gnu.org/gnu/gnunet/gnurl-7.57.0.tar.xz | ||
789 | $ wget https://ftp.gnu.org/gnu/gnunet/gnurl-7.57.0.tar.xz.sig | ||
790 | $ gpg --verify gnurl-7.57.0.tar.xz.sig | ||
791 | @end example | ||
792 | |||
793 | @noindent | ||
794 | If that command fails because you do not have the required public key, | ||
795 | then run this command to import it: | ||
796 | |||
797 | @example | ||
798 | $ gpg --keyserver pgp.mit.edu --recv-keys A88C8ADD129828D7EAC02E52E22F9BBFEE348588 | ||
799 | @end example | ||
800 | |||
801 | @noindent | ||
802 | and rerun the gpg --verify command. | ||
803 | |||
804 | @example | ||
805 | $ tar xvf gnurl-7.57.0.tar.xz | ||
806 | $ cd gnurl-7.57.0 | ||
807 | $ ./configure --disable-ntlm-wb | ||
808 | $ make ; sudo make install; cd .. | ||
809 | @end example | ||
810 | |||
811 | You have now build and installed libgnurl from source. | ||
812 | |||
813 | @menu | ||
814 | * Fixing libgnurl build issues:: | ||
815 | @end menu | ||
816 | |||
817 | @node Fixing libgnurl build issues | ||
818 | @subsubsection Fixing libgnurl build issues | ||
819 | |||
820 | @c FIXME: Obviously this subsection should be evaluated and | ||
821 | @c if still necessary moved into gnURL itself (README) or | ||
822 | @c into a separate section which deals with gnURL. | ||
823 | If you have to compile libgnurl from source (for example if the version | ||
824 | included in your distribution is too old or it's not included at all) | ||
825 | you perhaps might get an error message while running the | ||
826 | @command{configure} script: | ||
827 | |||
828 | @example | ||
829 | $ configure | ||
830 | ... | ||
831 | checking for 64-bit curl_off_t data type... unknown | ||
832 | checking for 32-bit curl_off_t data type... unknown | ||
833 | checking for 16-bit curl_off_t data type... unknown | ||
834 | configure: error: cannot find data type for curl_off_t. | ||
835 | @end example | ||
836 | |||
837 | @noindent | ||
838 | Solution: | ||
839 | |||
840 | Before running the @command{configure} script, set: | ||
841 | |||
842 | @example | ||
843 | CFLAGS="-I. -I$BUILD_ROOT/include" | ||
844 | @end example | ||
845 | |||
846 | @node Build Instructions for Microsoft Windows Platforms | ||
847 | @section Build Instructions for Microsoft Windows Platforms | ||
848 | |||
849 | @menu | ||
850 | * Introduction to building on MS Windows:: | ||
851 | * Requirements:: | ||
852 | * Dependencies & Initial Setup:: | ||
853 | * GNUnet Installation:: | ||
854 | * Adjusting Windows for running and testing GNUnet:: | ||
855 | * Building the GNUnet Installer:: | ||
856 | * Using GNUnet with Netbeans on Windows:: | ||
857 | @end menu | ||
858 | |||
859 | @node Introduction to building on MS Windows | ||
860 | @subsection Introduction to building on MS Windows | ||
861 | |||
862 | |||
863 | This document is a guide to building GNUnet and its dependencies on | ||
864 | Windows platforms. GNUnet development is mostly done under GNU/Linux and | ||
865 | especially git checkouts may not build out of the box. | ||
866 | We regret any inconvenience, and if you have problems, please report | ||
867 | them. | ||
868 | |||
869 | @node Requirements | ||
870 | @subsection Requirements | ||
871 | |||
872 | The Howto is based upon a @strong{Windows Server 2008 32bit} | ||
873 | @strong{Installation}, @strong{sbuild} and thus a | ||
874 | @uref{http://www.mingw.org/wiki/MSYS, MSYS+MinGW} | ||
875 | (W32-GCC-Compiler-Suite + Unix-like Userland) installation. sbuild | ||
876 | is a convenient set of scripts which creates a working msys/mingw | ||
877 | installation and installs most dependencies required for GNUnet. | ||
878 | |||
879 | As of the point of the creation of these instructions, | ||
880 | GNUnet @strong{requires} a Windows @strong{Server} 2003 or | ||
881 | newer for full feature support. | ||
882 | Windows Vista and later will also work, but | ||
883 | @strong{non-server version can not run a VPN-Exit-Node} as the NAT | ||
884 | features have been removed as of Windows Vista. | ||
885 | |||
886 | @c TODO: We should document Windows 10! | ||
887 | @c It seems like the situation hasn't changed with W10 | ||
888 | |||
889 | @node Dependencies & Initial Setup | ||
890 | @subsection Dependencies & Initial Setup | ||
891 | |||
892 | |||
893 | @itemize @bullet | ||
894 | |||
895 | @item | ||
896 | Install a fresh version of @strong{Python 2.x}, even if you are using a | ||
897 | x64-OS, install a 32-bit version for use with sbuild. | ||
898 | Python 3.0 is currently incompatible. | ||
899 | |||
900 | @item | ||
901 | Install your favorite @uref{http://code.google.com/p/tortoisegit/, git} & | ||
902 | @uref{http://tortoisesvn.net/, subversion}-clients. | ||
903 | |||
904 | @item | ||
905 | You will also need some archive-manager like | ||
906 | @uref{http://www.7-zip.org/, 7zip}. | ||
907 | |||
908 | @item | ||
909 | Pull a copy of sbuild to a directory of your choice, which will be used | ||
910 | in the remainder of this guide. For now, we will use | ||
911 | @file{c:\gnunet\sbuild\} | ||
912 | |||
913 | @item | ||
914 | in @file{sbuild\src\mingw\mingw32-buildall.sh}, comment out the packages | ||
915 | @strong{gnunet-svn} and @strong{gnunet-gtk-svn}, as we don't want sbuild | ||
916 | to compile/install those for us. | ||
917 | |||
918 | @item | ||
919 | Follow LRN's sbuild installation instructions.- | ||
920 | @end itemize | ||
921 | |||
922 | Please note that sbuild may (or will most likely) fail during | ||
923 | installation, thus you really HAVE to @strong{check the logfiles} created | ||
924 | during the installation process. | ||
925 | Certain packages may fail to build initially due to missing dependencies, | ||
926 | thus you may have to | ||
927 | @strong{substitute those with binary-versions initially}. Later on once | ||
928 | dependencies are satisfied you can re-build the newer package versions. | ||
929 | |||
930 | @strong{It is normal that you may have to repeat this step multiple times | ||
931 | and there is no uniform way to fix all compile-time issues, as the | ||
932 | build-process of many of the dependencies installed are rather unstable | ||
933 | on win32 and certain releases may not even compile at all.} | ||
934 | |||
935 | Most dependencies for GNUnet have been set up by sbuild, thus we now | ||
936 | should add the @file{bin/} directories in your new msys and mingw | ||
937 | installations to PATH. You will want to create a backup of your finished | ||
938 | msys-environment by now. | ||
939 | |||
940 | @node GNUnet Installation | ||
941 | @subsection GNUnet Installation | ||
942 | |||
943 | First, we need to launch our msys-shell, you can do this via | ||
944 | |||
945 | @file{C:\gnunet\sbuild\msys\msys.bat} | ||
946 | |||
947 | You might wish to take a look at this file and adjust some | ||
948 | login-parameters to your msys environment. | ||
949 | |||
950 | Also, sbuild added two pointpoints to your msys-environment, though those | ||
951 | might remain invisible: | ||
952 | |||
953 | @itemize @bullet | ||
954 | |||
955 | @item | ||
956 | /mingw, which will mount your mingw-directory from sbuild/mingw and the | ||
957 | other one is | ||
958 | |||
959 | @item | ||
960 | /src which contains all the installation sources sbuild just compiled. | ||
961 | @end itemize | ||
962 | |||
963 | Check out the current GNUnet sources (git HEAD) from the | ||
964 | GNUnet repository "gnunet.git", we will do this in your home directory: | ||
965 | |||
966 | @code{git clone https://gnunet.org/git/gnunet/ ~/gnunet} | ||
967 | |||
968 | Now, we will first need to bootstrap the checked out installation and then | ||
969 | configure it accordingly. | ||
970 | |||
971 | @example | ||
972 | cd ~/gnunet | ||
973 | ./bootstrap | ||
974 | STRIP=true CPPFLAGS="-DUSE_IPV6=1 -DW32_VEH" CFLAGS="$CFLAGS -g -O2" \ | ||
975 | ./configure --prefix=/ --docdir=/share/doc/gnunet \ | ||
976 | --with-libiconv-prefix=/mingw --with-libintl-prefix=/mingw \ | ||
977 | --with-libcurl=/mingw --with-extractor=/mingw --with-sqlite=/mingw \ | ||
978 | --with-microhttpd=/mingw --with-plibc=/mingw --enable-benchmarks \ | ||
979 | --enable-expensivetests --enable-experimental --with-qrencode=/mingw \ | ||
980 | --enable-silent-rules --enable-experimental 2>&1 | tee -a ./configure.log | ||
981 | @end example | ||
982 | |||
983 | The parameters above will configure for a reasonable GNUnet installation | ||
984 | to the your msys-root directory. | ||
985 | Depending on which features your would like to build or you may need to | ||
986 | specify additional dependencies. Sbuild installed most libs into | ||
987 | the /mingw subdirectory, so remember to prefix library locations with | ||
988 | this path. | ||
989 | |||
990 | Like on a unixoid system, you might want to use your home directory as | ||
991 | prefix for your own GNUnet installation for development, without tainting | ||
992 | the buildenvironment. Just change the "prefix" parameter to point towards | ||
993 | ~/ in this case. | ||
994 | |||
995 | Now it's time to compile GNUnet as usual. Though this will take some time, | ||
996 | so you may fetch yourself a coffee or some Mate now... | ||
997 | |||
998 | @example | ||
999 | make ; make install | ||
1000 | @end example | ||
1001 | |||
1002 | @node Adjusting Windows for running and testing GNUnet | ||
1003 | @subsection Adjusting Windows for running and testing GNUnet | ||
1004 | |||
1005 | Assuming the build succeeded and you | ||
1006 | @strong{added the bin directory of your GNUnet to PATH}, you can now use | ||
1007 | your gnunet-installation as usual. | ||
1008 | Remember that UAC or the windows firewall may popup initially, blocking | ||
1009 | further execution of gnunet until you acknowledge them. | ||
1010 | |||
1011 | You will also have to take the usual steps to get peer-to-peer (p2p) | ||
1012 | software running properly (port forwarding, ...), | ||
1013 | and GNUnet will require administrative permissions as it may even | ||
1014 | install a device-driver (in case you are using gnunet-vpn and/or | ||
1015 | gnunet-exit). | ||
1016 | |||
1017 | @node Building the GNUnet Installer | ||
1018 | @subsection Building the GNUnet Installer | ||
1019 | |||
1020 | The GNUnet installer is made with | ||
1021 | @uref{http://nsis.sourceforge.net/, NSIS}. | ||
1022 | The installer script is located in @file{contrib\win} in the | ||
1023 | GNUnet source tree. | ||
1024 | |||
1025 | @node Using GNUnet with Netbeans on Windows | ||
1026 | @subsection Using GNUnet with Netbeans on Windows | ||
1027 | |||
1028 | TODO | ||
1029 | |||
1030 | @node Build instructions for Debian 7.5 | ||
1031 | @section Build instructions for Debian 7.5 | ||
1032 | |||
1033 | |||
1034 | These are the installation instructions for Debian 7.5. They were tested | ||
1035 | using a minimal, fresh Debian 7.5 AMD64 installation without non-free | ||
1036 | software (no contrib or non-free). | ||
1037 | By "minimal", we mean that during installation, we did not select any | ||
1038 | desktop environment, servers or system utilities during the "tasksel" | ||
1039 | step. Note that the packages and the dependencies that we will install | ||
1040 | during this chapter take about 1.5 GB of disk space. | ||
1041 | Combined with GNUnet and space for objects during compilation, you should | ||
1042 | not even attempt this unless you have about 2.5 GB free after the minimal | ||
1043 | Debian installation. | ||
1044 | Using these instructions to build a VM image is likely to require a | ||
1045 | minimum of 4-5 GB for the VM (as you will likely also want a desktop | ||
1046 | manager). | ||
1047 | |||
1048 | GNUnet's security model assumes that your @file{/home} directory is | ||
1049 | encrypted. Thus, if possible, you should encrypt your home partition | ||
1050 | (or per-user home directory). | ||
1051 | |||
1052 | Naturally, the exact details of the starting state for your installation | ||
1053 | should not matter much. For example, if you selected any of those | ||
1054 | installation groups you might simply already have some of the necessary | ||
1055 | packages installed. | ||
1056 | We did this for testing, as this way we are less likely to forget to | ||
1057 | mention a required package. | ||
1058 | Note that we will not install a desktop environment, but of course you | ||
1059 | will need to install one to use GNUnet's graphical user interfaces. | ||
1060 | Thus, it is suggested that you simply install the desktop environment of | ||
1061 | your choice before beginning with the instructions. | ||
1062 | |||
1063 | |||
1064 | |||
1065 | @menu | ||
1066 | * Update:: | ||
1067 | * Stable? Hah!:: | ||
1068 | * Update again:: | ||
1069 | * Installing packages:: | ||
1070 | * Installing dependencies from source:: | ||
1071 | * Installing GNUnet from source:: | ||
1072 | * But wait there is more!:: | ||
1073 | @end menu | ||
1074 | |||
1075 | @node Update | ||
1076 | @subsection Update | ||
1077 | |||
1078 | After any installation, you should begin by running | ||
1079 | |||
1080 | @example | ||
1081 | # apt-get update ; apt-get upgrade | ||
1082 | @end example | ||
1083 | |||
1084 | to ensure that all of your packages are up-to-date. Note that the "#" is | ||
1085 | used to indicate that you need to type in this command as "root" | ||
1086 | (or prefix with "sudo"), whereas "$" is used to indicate typing in a | ||
1087 | command as a normal user. | ||
1088 | |||
1089 | @node Stable? Hah! | ||
1090 | @subsection Stable? Hah! | ||
1091 | |||
1092 | Yes, we said we start with a Debian 7.5 "stable" system. However, to | ||
1093 | reduce the amount of compilation by hand, we will begin by allowing the | ||
1094 | installation of packages from the testing and unstable distributions as | ||
1095 | well. | ||
1096 | We will stick to "stable" packages where possible, but some packages will | ||
1097 | be taken from the other distributions. | ||
1098 | Start by modifying @file{/etc/apt/sources.list} to contain the | ||
1099 | following (possibly adjusted to point to your mirror of choice): | ||
1100 | |||
1101 | @example | ||
1102 | # These were there before: | ||
1103 | deb http://ftp.de.debian.org/debian/ wheezy main | ||
1104 | deb-src http://ftp.de.debian.org/debian/ wheezy main | ||
1105 | deb http://security.debian.org/ wheezy/updates main | ||
1106 | deb-src http://security.debian.org/ wheezy/updates main | ||
1107 | deb http://ftp.de.debian.org/debian/ wheezy-updates main | ||
1108 | deb-src http://ftp.de.debian.org/debian/ wheezy-updates main | ||
1109 | |||
1110 | # Add these lines (feel free to adjust the mirror): | ||
1111 | deb http://ftp.de.debian.org/debian/ testing main | ||
1112 | deb http://ftp.de.debian.org/debian/ unstable main | ||
1113 | @end example | ||
1114 | |||
1115 | The next step is to create/edit your @file{/etc/apt/preferences} | ||
1116 | file to look like this: | ||
1117 | |||
1118 | @example | ||
1119 | Package: * | ||
1120 | Pin: release a=stable,n=wheezy | ||
1121 | Pin-Priority: 700 | ||
1122 | |||
1123 | Package: * | ||
1124 | Pin: release o=Debian,a=testing | ||
1125 | Pin-Priority: 650 | ||
1126 | |||
1127 | Package: * | ||
1128 | Pin: release o=Debian,a=unstable | ||
1129 | Pin-Priority: 600 | ||
1130 | @end example | ||
1131 | |||
1132 | You can read more about Apt Preferences here and here. | ||
1133 | Note that other pinnings are likely to also work for GNUnet, the key | ||
1134 | thing is that you need some packages from unstable (as shown below). | ||
1135 | However, as unstable is unlikely to be comprehensive (missing packages) | ||
1136 | or might be problematic (crashing packages), you probably want others | ||
1137 | from stable and/or testing. | ||
1138 | |||
1139 | @node Update again | ||
1140 | @subsection Update again | ||
1141 | |||
1142 | Now, run again@ | ||
1143 | |||
1144 | @example | ||
1145 | # apt-get update@ | ||
1146 | # apt-get upgrade@ | ||
1147 | @end example | ||
1148 | |||
1149 | to ensure that all your new distribution indices are downloaded, and | ||
1150 | that your pinning is correct: the upgrade step should cause no changes | ||
1151 | at all. | ||
1152 | |||
1153 | @node Installing packages | ||
1154 | @subsection Installing packages | ||
1155 | |||
1156 | We begin by installing a few Debian packages from stable:@ | ||
1157 | |||
1158 | @example | ||
1159 | # apt-get install gcc make python-zbar libltdl-dev libsqlite3-dev \ | ||
1160 | libunistring-dev libopus-dev libpulse-dev openssl libglpk-dev \ | ||
1161 | texlive libidn11-dev libmysqlclient-dev libpq-dev libarchive-dev \ | ||
1162 | libbz2-dev libexiv2-dev libflac-dev libgif-dev libglib2.0-dev \ | ||
1163 | libgtk-3-dev libmagic-dev libjpeg8-dev libmpeg2-4-dev libmp4v2-dev \ | ||
1164 | librpm-dev libsmf-dev libtidy-dev libtiff5-dev libvorbis-dev \ | ||
1165 | libogg-dev zlib1g-dev g++ gettext libgsf-1-dev libunbound-dev \ | ||
1166 | libqrencode-dev libgladeui-dev nasm texlive-latex-extra \ | ||
1167 | libunique-3.0-dev gawk miniupnpc libfuse-dev libbluetooth-dev | ||
1168 | @end example | ||
1169 | |||
1170 | After that, we install a few more packages from unstable:@ | ||
1171 | |||
1172 | @example | ||
1173 | # apt-get install -t unstable nettle-dev libgstreamer1.0-dev \ | ||
1174 | gstreamer1.0-plugins-base gstreamer1.0-plugins-good \ | ||
1175 | libgstreamer-plugins-base1.0-dev | ||
1176 | @end example | ||
1177 | |||
1178 | @node Installing dependencies from source | ||
1179 | @subsection Installing dependencies from source | ||
1180 | |||
1181 | Next, we need to install a few dependencies from source. | ||
1182 | You might want to do this as a "normal" user and only run the | ||
1183 | @code{make install} steps as root (hence the @code{sudo} in the | ||
1184 | commands below). Also, you do this from any | ||
1185 | directory. We begin by downloading all dependencies, then extracting the | ||
1186 | sources, and finally compiling and installing the libraries. | ||
1187 | |||
1188 | For these steps, follow the instructions given in the | ||
1189 | installation from source instruction in this order: | ||
1190 | |||
1191 | @itemize @bullet | ||
1192 | @item @ref{generic source installation - libav} | ||
1193 | @item @ref{generic source installation - libextractor} | ||
1194 | @item @ref{generic source installation - libgpg-error} | ||
1195 | @item @ref{generic source installation - libgcrypt} | ||
1196 | @item @ref{generic source installation - gnutls} | ||
1197 | @item @ref{generic source installation - libmicrohttpd} | ||
1198 | @item @ref{generic source installation - libgnurl} | ||
1199 | @end itemize | ||
1200 | |||
1201 | @node Installing GNUnet from source | ||
1202 | @subsection Installing GNUnet from source | ||
1203 | |||
1204 | |||
1205 | For this, simply follow the generic installation instructions from | ||
1206 | here. | ||
1207 | |||
1208 | @node But wait there is more! | ||
1209 | @subsection But wait there is more! | ||
1210 | |||
1211 | So far, we installed all of the packages and dependencies required to | ||
1212 | ensure that all of GNUnet would be built. | ||
1213 | However, while for example the plugins to interact with the MySQL or | ||
1214 | Postgres databases have been created, we did not actually install or | ||
1215 | configure those databases. Thus, you will need to install | ||
1216 | and configure those databases or stick with the default Sqlite database. | ||
1217 | Sqlite is usually fine for most applications, but MySQL can offer better | ||
1218 | performance and Postgres better resillience. | ||
1219 | |||
1220 | |||
1221 | @node Installing GNUnet from Git on Ubuntu 14.4 | ||
1222 | @section Installing GNUnet from Git on Ubuntu 14.4 | ||
1223 | |||
1224 | @strong{Install the required build tools:} | ||
1225 | |||
1226 | @example | ||
1227 | $ sudo apt-get install git automake autopoint autoconf | ||
1228 | @end example | ||
1229 | |||
1230 | @strong{Install the required dependencies} | ||
1231 | |||
1232 | @example | ||
1233 | $ sudo apt-get install libltdl-dev libgpg-error-dev libidn11-dev \ | ||
1234 | libunistring-dev libglpk-dev libbluetooth-dev libextractor-dev \ | ||
1235 | libmicrohttpd-dev libgnutls28-dev | ||
1236 | @end example | ||
1237 | |||
1238 | @strong{Choose one or more database backends} | ||
1239 | |||
1240 | @itemize @bullet | ||
1241 | |||
1242 | @item SQLite3: | ||
1243 | |||
1244 | @example | ||
1245 | $ sudo apt-get install libsqlite3-dev | ||
1246 | @end example | ||
1247 | |||
1248 | @item MySQL: | ||
1249 | |||
1250 | @example | ||
1251 | $ sudo apt-get install libmysqlclient-dev | ||
1252 | @end example | ||
1253 | |||
1254 | @item PostgreSQL: | ||
1255 | |||
1256 | @example | ||
1257 | $ sudo apt-get install libpq-dev postgresql | ||
1258 | @end example | ||
1259 | |||
1260 | @end itemize | ||
1261 | |||
1262 | @strong{Install the optional dependencies for gnunet-conversation:} | ||
1263 | |||
1264 | @example | ||
1265 | $ sudo apt-get install gstreamer1.0 libpulse-dev libopus-dev | ||
1266 | @end example | ||
1267 | |||
1268 | @strong{Install the libgrypt 1.6.1:} | ||
1269 | |||
1270 | @itemize @bullet | ||
1271 | |||
1272 | @item For Ubuntu 14.04: | ||
1273 | |||
1274 | @example | ||
1275 | $ sudo apt-get install libgcrypt20-dev | ||
1276 | @end example | ||
1277 | |||
1278 | @item For Ubuntu older 14.04: | ||
1279 | |||
1280 | @example | ||
1281 | $ wget ftp://ftp.gnupg.org/gcrypt/libgcrypt/libgcrypt-1.6.1.tar.bz2 | ||
1282 | $ tar xf libgcrypt-1.6.1.tar.bz2 | ||
1283 | $ cd libgcrypt-1.6.1 | ||
1284 | $ ./configure | ||
1285 | $ sudo make install | ||
1286 | $ cd .. | ||
1287 | @end example | ||
1288 | |||
1289 | @end itemize | ||
1290 | |||
1291 | @strong{Install libgnurl} | ||
1292 | |||
1293 | @example | ||
1294 | $ wget https://gnunet.org/sites/default/files/gnurl-7.35.0.tar.bz2 | ||
1295 | $ tar xf gnurl-7.35.0.tar.bz2 | ||
1296 | $ cd gnurl-7.35.0 | ||
1297 | $ ./configure --enable-ipv6 --with-gnutls --without-libssh2 \ | ||
1298 | --without-libmetalink --without-winidn --without-librtmp \ | ||
1299 | --without-nghttp2 --without-nss --without-cyassl --without-polarssl \ | ||
1300 | --without-ssl --without-winssl --without-darwinssl --disable-sspi \ | ||
1301 | --disable-ntlm-wb --disable-ldap --disable-rtsp --disable-dict \ | ||
1302 | --disable-telnet --disable-tftp --disable-pop3 --disable-imap \ | ||
1303 | --disable-smtp --disable-gopher --disable-file --disable-ftp | ||
1304 | $ sudo make install | ||
1305 | $ cd .. | ||
1306 | @end example | ||
1307 | |||
1308 | @strong{Install GNUnet} | ||
1309 | |||
1310 | @example | ||
1311 | $ git clone https://gnunet.org/git/gnunet/ | ||
1312 | $ cd gnunet/ | ||
1313 | $ ./bootstrap | ||
1314 | @end example | ||
1315 | |||
1316 | If you want to: | ||
1317 | |||
1318 | @itemize @bullet | ||
1319 | |||
1320 | @item Install to a different directory: | ||
1321 | |||
1322 | @example | ||
1323 | --prefix=PREFIX | ||
1324 | @end example | ||
1325 | |||
1326 | @item | ||
1327 | Have sudo permission, but do not want to compile as root: | ||
1328 | |||
1329 | @example | ||
1330 | --with-sudo | ||
1331 | @end example | ||
1332 | |||
1333 | @item | ||
1334 | Want debug message enabled: | ||
1335 | |||
1336 | @example | ||
1337 | --enable-logging=verbose | ||
1338 | @end example | ||
1339 | |||
1340 | @end itemize | ||
1341 | |||
1342 | |||
1343 | @example | ||
1344 | $ ./configure [ --with-sudo | --prefix=PREFIX | --enable-logging=verbose] | ||
1345 | $ make; sudo make install | ||
1346 | @end example | ||
1347 | |||
1348 | After installing it, you need to create an empty configuration file: | ||
1349 | |||
1350 | @example | ||
1351 | touch ~/.config/gnunet.conf | ||
1352 | @end example | ||
1353 | |||
1354 | And finally you can start GNUnet with | ||
1355 | |||
1356 | @example | ||
1357 | $ gnunet-arm -s | ||
1358 | @end example | ||
1359 | |||
1360 | @node Build instructions for Debian 8 | ||
1361 | @section Build instructions for Debian 8 | ||
1362 | @c FIXME: I -> we | ||
1363 | |||
1364 | These are the installation instructions for Debian 8. They were tested | ||
1365 | sing a fresh Debian 8 AMD64 installation without non-free software (no | ||
1366 | contrib or non-free). During installation, I only selected "lxde" for the | ||
1367 | desktop environment. | ||
1368 | Note that the packages and the dependencies that we will install during | ||
1369 | this chapter take about 1.5 GB of disk space. Combined with GNUnet and | ||
1370 | space for objects during compilation, you should not even attempt this | ||
1371 | unless you have about 2.5 GB free after the Debian installation. | ||
1372 | Using these instructions to build a VM image is likely to require a | ||
1373 | minimum of 4-5 GB for the VM (as you will likely also want a desktop | ||
1374 | manager). | ||
1375 | |||
1376 | GNUnet's security model assumes that your @code{/home} directory is | ||
1377 | encrypted. | ||
1378 | Thus, if possible, you should encrypt your entire disk, or at least just | ||
1379 | your home partition (or per-user home directory). | ||
1380 | |||
1381 | Naturally, the exact details of the starting state for your installation | ||
1382 | should not matter much. | ||
1383 | For example, if you selected any of those installation groups you might | ||
1384 | simply already have some of the necessary packages installed. Thus, it is | ||
1385 | suggested that you simply install the desktop environment of your choice | ||
1386 | before beginning with the instructions. | ||
1387 | |||
1388 | |||
1389 | @menu | ||
1390 | * Update Debian:: | ||
1391 | * Installing Debian Packages:: | ||
1392 | * Installing Dependencies from Source2:: | ||
1393 | * Installing GNUnet from Source2:: | ||
1394 | * But wait (again) there is more!:: | ||
1395 | @end menu | ||
1396 | |||
1397 | @node Update Debian | ||
1398 | @subsection Update Debian | ||
1399 | |||
1400 | After any installation, you should begin by running | ||
1401 | |||
1402 | @example | ||
1403 | # apt-get update | ||
1404 | # apt-get upgrade | ||
1405 | @end example | ||
1406 | |||
1407 | to ensure that all of your packages are up-to-date. Note that the "#" is | ||
1408 | used to indicate that you need to type in this command as "root" (or | ||
1409 | prefix with "sudo"), whereas "$" is used to indicate typing in a command | ||
1410 | as a normal user. | ||
1411 | |||
1412 | @node Installing Debian Packages | ||
1413 | @subsection Installing Debian Packages | ||
1414 | |||
1415 | We begin by installing a few Debian packages from stable: | ||
1416 | |||
1417 | @example | ||
1418 | # apt-get install gcc make python-zbar libltdl-dev libsqlite3-dev \ | ||
1419 | libunistring-dev libopus-dev libpulse-dev openssl libglpk-dev texlive \ | ||
1420 | libidn11-dev libmysqlclient-dev libpq-dev libarchive-dev libbz2-dev \ | ||
1421 | libflac-dev libgif-dev libglib2.0-dev libgtk-3-dev libmpeg2-4-dev \ | ||
1422 | libtidy-dev libvorbis-dev libogg-dev zlib1g-dev g++ gettext \ | ||
1423 | libgsf-1-dev libunbound-dev libqrencode-dev libgladeui-dev nasm \ | ||
1424 | texlive-latex-extra libunique-3.0-dev gawk miniupnpc libfuse-dev \ | ||
1425 | libbluetooth-dev gstreamer1.0-plugins-base gstreamer1.0-plugins-good \ | ||
1426 | libgstreamer-plugins-base1.0-dev nettle-dev libextractor-dev \ | ||
1427 | libgcrypt20-dev libmicrohttpd-dev | ||
1428 | @end example | ||
1429 | |||
1430 | @node Installing Dependencies from Source2 | ||
1431 | @subsection Installing Dependencies from Source2 | ||
1432 | |||
1433 | Yes, we said we start with a Debian 8 "stable" system, but because Debian | ||
1434 | linked GnuTLS without support for DANE, we need to compile a few things, | ||
1435 | in addition to GNUnet, still by hand. Yes, you can run GNUnet using the | ||
1436 | respective Debian packages, but then you will not get DANE support. | ||
1437 | |||
1438 | Next, we need to install a few dependencies from source. You might want | ||
1439 | to do this as a "normal" user and only run the @code{make install} steps | ||
1440 | as root (hence the @code{sudo} in the commands below). Also, you do this | ||
1441 | from any directory. We begin by downloading all dependencies, then | ||
1442 | extracting the sources, and finally compiling and installing the | ||
1443 | libraries: | ||
1444 | |||
1445 | @example | ||
1446 | $ wget ftp://ftp.gnutls.org/gcrypt/gnutls/v3.3/gnutls-3.3.12.tar.xz | ||
1447 | $ tar xvf gnutls-3.3.12.tar.xz | ||
1448 | $ cd gnutls-3.3.12 ; ./configure ; make ; sudo make install ; cd .. | ||
1449 | @end example | ||
1450 | |||
1451 | For the installation and compilation of libgnurl/gnURL refer to | ||
1452 | the generic installation section, | ||
1453 | @xref{generic source installation - libgnurl}. | ||
1454 | |||
1455 | @node Installing GNUnet from Source2 | ||
1456 | @subsection Installing GNUnet from Source2 | ||
1457 | |||
1458 | For this, simply follow the generic installation instructions from@ | ||
1459 | here. | ||
1460 | |||
1461 | @node But wait (again) there is more! | ||
1462 | @subsection But wait (again) there is more! | ||
1463 | |||
1464 | So far, we installed all of the packages and dependencies required to | ||
1465 | ensure that all of GNUnet would be built. However, while for example the | ||
1466 | plugins to interact with the MySQL or Postgres databases have been | ||
1467 | created, we did not actually install or configure those databases. | ||
1468 | Thus, you will need to install and configure those databases or stick | ||
1469 | with the default Sqlite database. Sqlite is usually fine for most | ||
1470 | applications, but MySQL can offer better performance and Postgres better | ||
1471 | resillience. | ||
1472 | |||
1473 | @node Outdated build instructions for previous revisions | ||
1474 | @section Outdated build instructions for previous revisions | ||
1475 | |||
1476 | This chapter contains a collection of outdated, older installation guides. | ||
1477 | They are mostly intended to serve as a starting point for writing | ||
1478 | up-to-date instructions and should not be expected to work for | ||
1479 | GNUnet 0.10.x. | ||
1480 | A set of older installation instructions can also be found in the | ||
1481 | file @file{doc/outdated-and-old-installation-instructions.txt} in the | ||
1482 | source tree of GNUnet. | ||
1483 | |||
1484 | This file covers old instructions which no longer receive security | ||
1485 | updates or any kind of support. | ||
1486 | |||
1487 | @menu | ||
1488 | * Installing GNUnet 0.10.1 on Ubuntu 14.04:: | ||
1489 | * Building GLPK for MinGW:: | ||
1490 | * GUI build instructions for Ubuntu 12.04 using Subversion:: | ||
1491 | @c * Installation with gnunet-update:: | ||
1492 | * Instructions for Microsoft Windows Platforms (Old):: | ||
1493 | @end menu | ||
1494 | |||
1495 | |||
1496 | @node Installing GNUnet 0.10.1 on Ubuntu 14.04 | ||
1497 | @subsection Installing GNUnet 0.10.1 on Ubuntu 14.04 | ||
1498 | |||
1499 | Install the required dependencies: | ||
1500 | |||
1501 | @example | ||
1502 | $ sudo apt-get install libltdl-dev libgpg-error-dev libidn11-dev \ | ||
1503 | libunistring-dev libglpk-dev libbluetooth-dev libextractor-dev \ | ||
1504 | libmicrohttpd-dev libgnutls28-dev | ||
1505 | @end example | ||
1506 | |||
1507 | Choose one or more database backends: | ||
1508 | |||
1509 | @itemize @bullet | ||
1510 | |||
1511 | @item SQLite3 | ||
1512 | |||
1513 | @example | ||
1514 | $ sudo apt-get install libsqlite3-dev@ | ||
1515 | @end example | ||
1516 | |||
1517 | @item MySQL | ||
1518 | |||
1519 | @example | ||
1520 | $ sudo apt-get install libmysqlclient-dev@ | ||
1521 | @end example | ||
1522 | |||
1523 | @item PostgreSQL | ||
1524 | |||
1525 | @example | ||
1526 | $ sudo apt-get install libpq-dev postgresql@ | ||
1527 | @end example | ||
1528 | |||
1529 | @end itemize | ||
1530 | |||
1531 | Install the optional dependencies for gnunet-conversation: | ||
1532 | |||
1533 | @example | ||
1534 | $ sudo apt-get install gstreamer1.0 libpulse-dev libopus-dev | ||
1535 | @end example | ||
1536 | |||
1537 | Install libgcrypt 1.6: | ||
1538 | |||
1539 | @itemize @bullet | ||
1540 | |||
1541 | @item For Ubuntu 14.04: | ||
1542 | |||
1543 | @example | ||
1544 | $ sudo apt-get install libgcrypt20-dev | ||
1545 | @end example | ||
1546 | |||
1547 | @item For Ubuntu older than 14.04: | ||
1548 | |||
1549 | @example | ||
1550 | wget ftp://ftp.gnupg.org/gcrypt/libgcrypt/libgcrypt-1.6.1.tar.bz2 | ||
1551 | $ tar xf libgcrypt-1.6.1.tar.bz2 | ||
1552 | $ cd libgcrypt-1.6.1 | ||
1553 | $ ./configure | ||
1554 | $ sudo make install | ||
1555 | $ cd .. | ||
1556 | @end example | ||
1557 | @end itemize | ||
1558 | |||
1559 | Install libgnurl: | ||
1560 | |||
1561 | @pxref{generic source installation - libgnurl}. | ||
1562 | |||
1563 | Install GNUnet: | ||
1564 | |||
1565 | @example | ||
1566 | $ wget http://ftpmirror.gnu.org/gnunet/gnunet-0.10.1.tar.gz | ||
1567 | $ tar xf gnunet-0.10.1.tar.gz | ||
1568 | $ cd gnunet-0.10.1 | ||
1569 | @end example | ||
1570 | |||
1571 | If you want to: | ||
1572 | |||
1573 | @itemize @bullet | ||
1574 | |||
1575 | @item | ||
1576 | Install to a different directory: | ||
1577 | |||
1578 | @example | ||
1579 | --prefix=PREFIX | ||
1580 | @end example | ||
1581 | |||
1582 | @item | ||
1583 | Have sudo permission, but do not want to compile as root: | ||
1584 | |||
1585 | @example | ||
1586 | --with-sudo | ||
1587 | @end example | ||
1588 | |||
1589 | @item | ||
1590 | Want debug message enabled: | ||
1591 | |||
1592 | @example | ||
1593 | --enable-logging=verbose | ||
1594 | @end example | ||
1595 | |||
1596 | @end itemize | ||
1597 | |||
1598 | @example | ||
1599 | $ ./configure [ --with-sudo | --prefix=PREFIX | --enable-logging=verbose] | ||
1600 | $ make; sudo make install | ||
1601 | @end example | ||
1602 | |||
1603 | After installing it, you need to create an empty configuration file: | ||
1604 | |||
1605 | @example | ||
1606 | touch ~/.config/gnunet.conf | ||
1607 | @end example | ||
1608 | |||
1609 | And finally you can start GNUnet with | ||
1610 | |||
1611 | @example | ||
1612 | $ gnunet-arm -s | ||
1613 | @end example | ||
1614 | |||
1615 | @node Building GLPK for MinGW | ||
1616 | @subsection Building GLPK for MinGW | ||
1617 | |||
1618 | GNUnet now requires the GNU Linear Programming Kit (GLPK). | ||
1619 | Since there's is no package you can install with @code{mingw-get} you | ||
1620 | have to compile it from source: | ||
1621 | |||
1622 | @itemize @bullet | ||
1623 | |||
1624 | @item Download the latest version from | ||
1625 | @uref{http://ftp.gnu.org/gnu/glpk/} | ||
1626 | |||
1627 | @item Unzip the downloaded source tarball using your favourite | ||
1628 | unzipper application In the MSYS shell | ||
1629 | |||
1630 | @item change to the respective directory | ||
1631 | |||
1632 | @item Configure glpk for "i686-pc-mingw32": | ||
1633 | |||
1634 | @example | ||
1635 | ./configure '--build=i686-pc-mingw32' | ||
1636 | @end example | ||
1637 | |||
1638 | @item run | ||
1639 | |||
1640 | @example | ||
1641 | make install check | ||
1642 | @end example | ||
1643 | |||
1644 | @end itemize | ||
1645 | |||
1646 | MinGW does not automatically detect the correct buildtype so you have to | ||
1647 | specify it manually. | ||
1648 | |||
1649 | |||
1650 | @node GUI build instructions for Ubuntu 12.04 using Subversion | ||
1651 | @subsection GUI build instructions for Ubuntu 12.04 using Subversion | ||
1652 | |||
1653 | After installing GNUnet you can continue installing the GNUnet GUI tools: | ||
1654 | |||
1655 | First, install the required dependencies: | ||
1656 | |||
1657 | @example | ||
1658 | $ sudo apt-get install libgladeui-dev libqrencode-dev | ||
1659 | @end example | ||
1660 | |||
1661 | Please ensure that the GNUnet shared libraries can be found by the linker. | ||
1662 | If you installed GNUnet libraries in a non standard path | ||
1663 | (say GNUNET_PREFIX=/usr/local/lib/), you can | ||
1664 | |||
1665 | @itemize @bullet | ||
1666 | |||
1667 | @item set the environmental variable permanently to: | ||
1668 | |||
1669 | @example | ||
1670 | LD_LIBRARY_PATH=$GNUNET_PREFIX | ||
1671 | @end example | ||
1672 | |||
1673 | @item or add @code{$GNUNET_PREFIX} to @file{/etc/ld.so.conf} | ||
1674 | |||
1675 | @end itemize | ||
1676 | |||
1677 | Now you can checkout and compile the GNUnet GUI tools: | ||
1678 | |||
1679 | @example | ||
1680 | $ git clone https://gnunet.org/git/gnunet-gtk | ||
1681 | $ cd gnunet-gtk | ||
1682 | $ ./bootstrap | ||
1683 | $ ./configure --prefix=$GNUNET_PREFIX/.. --with-gnunet=$GNUNET_PREFIX/.. | ||
1684 | $ make install | ||
1685 | @end example | ||
1686 | |||
1687 | @c @node Installation with gnunet-update | ||
1688 | @c @subsection Installation with gnunet-update | ||
1689 | |||
1690 | @c gnunet-update project is an effort to introduce updates to GNUnet | ||
1691 | @c installations. An interesting to-be-implemented-feature of gnunet-update | ||
1692 | @c is that these updates are propagated through GNUnet's peer-to-peer | ||
1693 | @c network. More information about gnunet-update can be found at | ||
1694 | @c @c FIXME: Use correct cgit URL | ||
1695 | @c @uref{https://gnunet.org/git/gnunet-update.git/tree/plain/README}. | ||
1696 | |||
1697 | @c While the project is still under development, we have implemented the | ||
1698 | @c following features which we believe may be helpful for users and we | ||
1699 | @c would like them to be tested: | ||
1700 | |||
1701 | @c @itemize @bullet | ||
1702 | |||
1703 | @c @item | ||
1704 | @c Packaging GNUnet installation along with its run-time dependencies into | ||
1705 | @c update packages | ||
1706 | |||
1707 | @c @item | ||
1708 | @c Installing update packages into compatible hosts | ||
1709 | |||
1710 | @c @item | ||
1711 | @c Updating an existing installation (which had been installed by | ||
1712 | @c gnunet-update) to a newer one | ||
1713 | |||
1714 | @c @end itemize | ||
1715 | |||
1716 | @c The above said features of gnunet-update are currently available for | ||
1717 | @c testing on GNU/Linux systems. | ||
1718 | |||
1719 | @c The following is a guide to help you get started with gnunet-update. | ||
1720 | @c It shows you how to install the testing binary packages of GNUnet | ||
1721 | @c 0.9.1 we have at @uref{https://gnunet.org/install/}. | ||
1722 | |||
1723 | @c gnunet-update needs the following dependencies: | ||
1724 | |||
1725 | @c @itemize @bullet | ||
1726 | @c @item | ||
1727 | @c python @geq{} 2.6 | ||
1728 | |||
1729 | @c @item | ||
1730 | @c gnupg | ||
1731 | |||
1732 | @c @item | ||
1733 | @c python-gpgme | ||
1734 | @c @end itemize | ||
1735 | |||
1736 | |||
1737 | @c Checkout gnunet-update: | ||
1738 | |||
1739 | @c @c FIXME: git! | ||
1740 | @c @example | ||
1741 | @c $ svn checkout -r24905 https://gnunet.org/svn/gnunet-update@ | ||
1742 | @c @end example | ||
1743 | |||
1744 | @c For security reasons, all packages released for gnunet-update from us are | ||
1745 | @c signed with the key at @uref{https://gnunet.org/install/key.txt}. | ||
1746 | @c You would need to import this key into your gpg key ring. | ||
1747 | @c gnunet-update uses this key to verify the integrity of the packages it | ||
1748 | @c installs: | ||
1749 | |||
1750 | @c @example | ||
1751 | @c $ gpg --recv-keys 7C613D78@ | ||
1752 | @c @end example | ||
1753 | |||
1754 | @c Download the packages relevant to your architecture (currently I have | ||
1755 | @c access to GNU/Linux machines on x86_64 and i686, so only two for now, | ||
1756 | @c hopefully more later) from https://gnunet.org/install/. | ||
1757 | |||
1758 | @c To install the downloaded package into the directory /foo: | ||
1759 | |||
1760 | @c @example | ||
1761 | @c gnunet-update/bin/gnunet-update install downloaded/package /foo | ||
1762 | @c @end example | ||
1763 | |||
1764 | @c The installer reports the directories into which shared libraries and | ||
1765 | @c dependencies have been installed. You may need to add the reported shared | ||
1766 | @c library installation paths to LD_LIBRARY_PATH before you start running any | ||
1767 | @c installed binaries. | ||
1768 | |||
1769 | @c Please report bugs at https://gnunet.org/bugs/ under the project | ||
1770 | @c 'gnunet-update'. | ||
1771 | |||
1772 | @node Instructions for Microsoft Windows Platforms (Old) | ||
1773 | @subsection Instructions for Microsoft Windows Platforms (Old) | ||
1774 | |||
1775 | This document is a @b{DEPRECATED} installation guide for GNUnet on | ||
1776 | Windows. | ||
1777 | It will not work for recent GNUnet versions, but maybe it will be of | ||
1778 | some use if problems arise. | ||
1779 | |||
1780 | The Windows build uses a UNIX emulator for Windows, | ||
1781 | @uref{http://www.mingw.org/, MinGW}, to build the executable modules. | ||
1782 | These modules run natively on Windows and do not require additional | ||
1783 | emulation software besides the usual dependencies. | ||
1784 | |||
1785 | GNUnet development is mostly done under GNU/Linux and especially git | ||
1786 | checkouts may not build out of the box. | ||
1787 | We regret any inconvenience, and if you have problems, please report them. | ||
1788 | |||
1789 | @menu | ||
1790 | * Hardware and OS requirements:: | ||
1791 | * Software installation:: | ||
1792 | * Building libextractor and GNUnet:: | ||
1793 | * Installer:: | ||
1794 | * Source:: | ||
1795 | @end menu | ||
1796 | |||
1797 | @node Hardware and OS requirements | ||
1798 | @subsubsection Hardware and OS requirements | ||
1799 | |||
1800 | @itemize @bullet | ||
1801 | |||
1802 | @item Pentium II or equivalent processor, @geq{} 350 MHz | ||
1803 | |||
1804 | @item 128 MB RAM | ||
1805 | |||
1806 | @item 600 MB free disk space | ||
1807 | |||
1808 | @item Windows 2000 or Windows XP are recommended | ||
1809 | |||
1810 | @end itemize | ||
1811 | |||
1812 | @node Software installation | ||
1813 | @subsubsection Software installation | ||
1814 | |||
1815 | @itemize @bullet | ||
1816 | |||
1817 | @item | ||
1818 | @strong{Compression software}@ | ||
1819 | |||
1820 | The software packages GNUnet depends on are usually compressed using UNIX | ||
1821 | tools like @command{tar}, @command{gzip}, @command{xzip} and | ||
1822 | @command{bzip2}. | ||
1823 | If you do not already have an utility that is able to extract such | ||
1824 | archives, get @uref{http://www.7-zip.org/, 7-Zip}. | ||
1825 | |||
1826 | @item | ||
1827 | @strong{UNIX environment}@ | ||
1828 | |||
1829 | The MinGW project provides the compiler toolchain that is used to build | ||
1830 | GNUnet. | ||
1831 | Get the following packages from the | ||
1832 | @uref{http://sourceforge.net/projects/mingw/files/, MinGW} project: | ||
1833 | |||
1834 | @itemize @bullet | ||
1835 | |||
1836 | @item GCC core | ||
1837 | @item GCC g++ | ||
1838 | @item MSYS | ||
1839 | @item MSYS Developer Tool Kit (msysDTK) | ||
1840 | @item MSYS Developer Tool Kit - msys-autoconf (bin) | ||
1841 | @item MSYS Developer Tool Kit - msys-automake (bin) | ||
1842 | @item MinGW Runtime | ||
1843 | @item MinGW Utilities | ||
1844 | @item Windows API | ||
1845 | @item Binutils | ||
1846 | @item make | ||
1847 | @item pdcurses | ||
1848 | @item GDB (snapshot) | ||
1849 | @end itemize | ||
1850 | |||
1851 | @itemize @bullet | ||
1852 | |||
1853 | |||
1854 | @item Install MSYS (to c:\mingw, for example.)@ | ||
1855 | Do @strong{not} use spaces in the pathname. | ||
1856 | For example, avoid a location such as @file{c:\program files\mingw}. | ||
1857 | |||
1858 | @item Install MinGW runtime, utilities and GCC to a subdirectory | ||
1859 | (to @file{c:\mingw\mingw}, for example) | ||
1860 | |||
1861 | @item Install the Development Kit to the MSYS directory | ||
1862 | (@file{c:\mingw}) | ||
1863 | |||
1864 | @item Create a batch file bash.bat in your MSYS directory with | ||
1865 | the files: | ||
1866 | |||
1867 | @example | ||
1868 | bin\sh.exe --login | ||
1869 | @end example | ||
1870 | |||
1871 | This batch file opens a shell which is used to invoke the build | ||
1872 | processes. | ||
1873 | MinGW's standard shell (@command{msys.bat}) is not suitable | ||
1874 | because it opens a separate console window. | ||
1875 | On Vista, @command{bash.bat} needs to be run as Administrator. | ||
1876 | |||
1877 | @item | ||
1878 | Start @command{bash.sh} and rename | ||
1879 | @file{c:\mingw\mingw\lib\libstdc++.la} to avoid problems: | ||
1880 | |||
1881 | @example | ||
1882 | mv /usr/mingw/lib/libstdc++.la /usr/mingw/lib/libstdc++.la.broken | ||
1883 | @end example | ||
1884 | |||
1885 | @item | ||
1886 | Unpack the Windows API to the MinGW directory (@file{c:\mingw\mingw\}) and | ||
1887 | remove the declaration of DATADIR from | ||
1888 | (@file{c:\mingw\mingw\include\objidl.h} (lines 55-58) | ||
1889 | |||
1890 | @item | ||
1891 | Unpack autoconf, automake to the MSYS directory (@file{c:\mingw}) | ||
1892 | |||
1893 | @item | ||
1894 | Install all other packages to the MinGW directory (@file{c:\mingw\mingw\}) | ||
1895 | @end itemize | ||
1896 | |||
1897 | |||
1898 | @item @strong{GNU Libtool}@ | ||
1899 | GNU Libtool is required to use shared libraries. | ||
1900 | Get the prebuilt package from here and unpack it to the | ||
1901 | MinGW directory (@file{c:\mingw}) | ||
1902 | |||
1903 | @item @strong{Pthreads}@ | ||
1904 | GNUnet uses the portable POSIX thread library for multi-threading: | ||
1905 | |||
1906 | @itemize @bullet | ||
1907 | |||
1908 | @item Save | ||
1909 | @uref{ftp://sources.redhat.com/pub/pthreads-win32/dll-latest/lib/x86/libpthreadGC2.a, libpthreadGC2.a} | ||
1910 | (x86) or | ||
1911 | @uref{ftp://sources.redhat.com/pub/pthreads-win32/dll-latest/lib/x64/libpthreadGC2.a, libpthreadGC2.a} | ||
1912 | (x64) as libpthread.a into the @file{lib} | ||
1913 | directory (@file{c:\mingw\mingw\lib\libpthread.a}). | ||
1914 | |||
1915 | @item Save | ||
1916 | @uref{ftp://sources.redhat.com/pub/pthreads-win32/dll-latest/lib/x86/pthreadGC2.dll, pthreadGC2.dll} | ||
1917 | (x86) or | ||
1918 | @uref{ftp://sources.redhat.com/pub/pthreads-win32/dll-latest/lib/x64/pthreadGC2.dll, libpthreadGC2.a} | ||
1919 | (x64) into the MinGW @file{bin} directory (@file{c:\mingw\mingw\bin}). | ||
1920 | |||
1921 | @item Download all header files from | ||
1922 | @uref{ftp://sources.redhat.com/pub/pthreads-win32/dll-latest/include/, include/} | ||
1923 | to the @file{include} directory (@file{c:\mingw\mingw\include}). | ||
1924 | @end itemize | ||
1925 | |||
1926 | |||
1927 | @item @strong{GNU MP}@ | ||
1928 | GNUnet uses the GNU Multiple Precision library for special cryptographic | ||
1929 | operations. Get the GMP binary package from the | ||
1930 | @uref{http://sourceforge.net/projects/mingwrep/, MinGW repository} and | ||
1931 | unpack it to the MinGW directory (@file{c:\mingw\mingw}) | ||
1932 | |||
1933 | @item @strong{GNU Gettext}@ | ||
1934 | GNU gettext is used to provide national language support. | ||
1935 | Get the prebuilt package from hereand unpack it to the MinGW | ||
1936 | directory (@file{c:\mingw\mingw}) | ||
1937 | |||
1938 | @item @strong{GNU iconv}@ | ||
1939 | GNU Libiconv is used for character encoding conversion. | ||
1940 | Get the prebuilt package from here and unpack it to the MinGW | ||
1941 | directory (@file{c:\mingw\mingw}). | ||
1942 | |||
1943 | @item @strong{SQLite}@ | ||
1944 | GNUnet uses the SQLite database to store data. | ||
1945 | Get the prebuilt binary from here and unpack it to your MinGW directory. | ||
1946 | |||
1947 | @item @strong{MySQL}@ | ||
1948 | As an alternative to SQLite, GNUnet also supports MySQL. | ||
1949 | |||
1950 | @itemize @bullet | ||
1951 | |||
1952 | @item Get the binary installer from the | ||
1953 | @uref{http://dev.mysql.com/downloads/mysql/4.1.html#Windows, MySQL project} | ||
1954 | (version 4.1), install it and follow the instructions in | ||
1955 | @file{README.mysql}. | ||
1956 | |||
1957 | @item Create a temporary build directory (@file{c:\mysql}) | ||
1958 | |||
1959 | @item Copy the directories @file{include\} and @file{lib\} from the | ||
1960 | MySQL directory to the new directory | ||
1961 | |||
1962 | @item Get the patches from | ||
1963 | @uref{http://bugs.mysql.com/bug.php?id=8906&files=1, Bug #8906} and | ||
1964 | @uref{http://bugs.mysql.com/bug.php?id=8872&files=1, Bug #8872} (the | ||
1965 | latter is only required for MySQL | ||
1966 | |||
1967 | @example | ||
1968 | patch -p 0 | ||
1969 | @end example | ||
1970 | |||
1971 | @item Move @file{lib\opt\libmysql.dll} to @file{lib\libmysql.dll} | ||
1972 | |||
1973 | @item Change to @file{lib\} and create an import library: | ||
1974 | |||
1975 | @example | ||
1976 | dlltool --input-def ../include/libmySQL.def \ | ||
1977 | --dllname libmysql.dll \ | ||
1978 | --output-lib libmysqlclient.a -k | ||
1979 | @end example | ||
1980 | |||
1981 | @item Copy include\* to include\mysql\ | ||
1982 | |||
1983 | @item Pass @code{--with-mysql=/c/mysql} to | ||
1984 | @command{./configure} and copy @file{libmysql.dll} | ||
1985 | to your PATH or GNUnet's @file{bin} directory | ||
1986 | @end itemize | ||
1987 | |||
1988 | |||
1989 | @item @strong{GTK+}@ | ||
1990 | @command{gnunet-gtk} and @command{libextractor} depend on GTK. | ||
1991 | Get the the binary and developer packages of @command{atk}, | ||
1992 | @command{glib}, @command{gtk}, @command{iconv}, | ||
1993 | @command{gettext-runtime}, @command{pango} from | ||
1994 | @uref{ftp://ftp.gtk.org/pub/gtk/v2.6/win32, gtk.org} and unpack them | ||
1995 | to the MinGW directory (@file{c:\mingw\mingw}). | ||
1996 | @c FIXME: The URL below for pkg-config seems wrong. | ||
1997 | Get @uref{http://www.gtk.org/download/win32.php, pkg-config} and | ||
1998 | @command{libpng} and unpack them to the MinGW directory | ||
1999 | (@file{c:\mingw\mingw}). | ||
2000 | Here is an all-in-one package for the | ||
2001 | @uref{http://ftp.gnome.org/pub/gnome/binaries/win32/gtk+/2.24/gtk+-bundle_2.24.10-20120208_win32.zip, gtk+dependencies} | ||
2002 | . Do not overwrite any existing files! | ||
2003 | |||
2004 | @item @strong{Glade}@ | ||
2005 | @command{gnunet-gtk} and @command{gnunet-setup} were created using | ||
2006 | this interface builder | ||
2007 | |||
2008 | @itemize @bullet | ||
2009 | |||
2010 | @item Get the Glade and libglade (-bin and -devel) packages | ||
2011 | (without GTK!) from | ||
2012 | @uref{http://gladewin32.sourceforge.net/, GladeWin32} and unpack them to | ||
2013 | the MinGW directory (@file{c:\mingw\mingw}). | ||
2014 | |||
2015 | @item Get @command{libxml} from here and unpack it to the MinGW | ||
2016 | directory (@file{c:\mingw\mingw}). | ||
2017 | @end itemize | ||
2018 | |||
2019 | @c FIXME: URLs | ||
2020 | @item @strong{zLib}@ | ||
2021 | @command{libextractor} requires @command{zLib} to decompress some file | ||
2022 | formats. GNUnet uses it to (de)compress meta-data. | ||
2023 | Get zLib from here (Signature) and unpack it to the MinGW directory | ||
2024 | (@file{c:\mingw\mingw}). | ||
2025 | |||
2026 | @item @strong{Bzip2}@ | ||
2027 | @command{libextractor} also requires @command{Bzip2} to | ||
2028 | decompress some file formats. | ||
2029 | Get the Bzip2 (binary and developer package) from | ||
2030 | @uref{http://gnuwin32.sourceforge.net/packages/bzip2.htm, GnuWin32} and | ||
2031 | unpack it to the MinGW directory (@file{c:\mingw\mingw}). | ||
2032 | |||
2033 | @item @strong{Libgcrypt}@ | ||
2034 | @command{Libgcrypt} provides the cryptographic functions used by GNUnet. | ||
2035 | Get Libgcrypt from @uref{ftp://ftp.gnupg.org/gcrypt/libgcrypt/, here}, | ||
2036 | compile and place it in the MinGW directory | ||
2037 | (@file{c:\mingw\mingw}). Currently libgcrypt @geq{} 1.4.2 is required to | ||
2038 | compile GNUnet. | ||
2039 | |||
2040 | @item @strong{PlibC}@ | ||
2041 | PlibC emulates Unix functions under Windows. Get PlibC from here and | ||
2042 | unpack it to the MinGW directory (c:\mingw\mingw) | ||
2043 | |||
2044 | @item @strong{OGG Vorbis}@ | ||
2045 | @command{OGG Vorbis} is used to extract meta-data from @file{.ogg} files. | ||
2046 | Get the packages | ||
2047 | @uref{http://www.gnunet.org/libextractor/download/win/libogg-1.1.4.zip, libogg} | ||
2048 | and | ||
2049 | @uref{http://www.gnunet.org/libextractor/download/win/libvorbis-1.2.3.zip, libvorbis} | ||
2050 | from the | ||
2051 | @uref{http://ftp.gnu.org/gnu/libextractor/libextractor-w32-1.0.0.zip, libextractor win32 build} | ||
2052 | and unpack them to the MinGW directory (c:\mingw\mingw). | ||
2053 | |||
2054 | @item @strong{Exiv2}@ | ||
2055 | (lib)Exiv2 is used to extract meta-data from files with Exiv2 meta-data. | ||
2056 | Download | ||
2057 | @uref{http://www.gnunet.org/libextractor/download/win/exiv2-0.18.2.zip, Exiv2} | ||
2058 | and unpack it to the MSYS directory (c:\mingw). | ||
2059 | @end itemize | ||
2060 | |||
2061 | @node Building libextractor and GNUnet | ||
2062 | @subsubsection Building libextractor and GNUnet | ||
2063 | |||
2064 | Before you compile @command{libextractor} or @command{GNUnet}, | ||
2065 | be sure to set @code{PKG_CONFIG_PATH}: | ||
2066 | |||
2067 | @example | ||
2068 | export PKG_CONFIG_PATH=/mingw/lib/pkgconfig | ||
2069 | @end example | ||
2070 | |||
2071 | @noindent | ||
2072 | @xref{GNUnet Installation Handbook}, for basic instructions on building | ||
2073 | @command{libextractor} and @command{GNUnet}. | ||
2074 | By default, all modules that are created in this way contain | ||
2075 | debug information and are quite large. To compile release versions | ||
2076 | (small and fast) set the variable @code{CFLAGS}: | ||
2077 | |||
2078 | @example | ||
2079 | export CFLAGS='-O2 -march=pentium -fomit-frame-pointer' | ||
2080 | ./configure --prefix=$HOME --with-extractor=$HOME | ||
2081 | @end example | ||
2082 | |||
2083 | @node Installer | ||
2084 | @subsubsection Installer | ||
2085 | |||
2086 | The GNUnet installer is made with | ||
2087 | @uref{http://nsis.sourceforge.net/, NSIS}. The installer script is | ||
2088 | located in @file{contrib\win} in the GNUnet source tree. | ||
2089 | |||
2090 | @node Source | ||
2091 | @subsubsection Source | ||
2092 | |||
2093 | @c FIXME: URL | ||
2094 | The sources of all dependencies are available here. | ||
2095 | |||
2096 | @c @node Portable GNUnet | ||
2097 | @c @section Portable GNUnet | ||
2098 | |||
2099 | @c Quick instructions on how to use the most recent GNUnet on most GNU/Linux | ||
2100 | @c distributions | ||
2101 | |||
2102 | @c Currently this has only been tested on Ubuntu 12.04, 12.10, 13.04, Debian | ||
2103 | @c and CentOS 6, but it should work on almost any GNU/Linux distribution. | ||
2104 | @c More in-detail information can be found in the handbook. | ||
2105 | |||
2106 | @c Note 2017-10: Currently this section assumes the old SVN repo of GNUnet | ||
2107 | @c which no longer exists. | ||
2108 | |||
2109 | @c @menu | ||
2110 | @c * Prerequisites:: | ||
2111 | @c * Download & set up gnunet-update:: | ||
2112 | @c * Install GNUnet:: | ||
2113 | @c @end menu | ||
2114 | |||
2115 | @c @node Prerequisites | ||
2116 | @c @subsection Prerequisites | ||
2117 | |||
2118 | @c Open a terminal and paste this line into it to install all required tools | ||
2119 | @c needed: | ||
2120 | |||
2121 | @c @example | ||
2122 | @c sudo apt-get install python-gpgme subversion | ||
2123 | @c @end example | ||
2124 | |||
2125 | @c @node Download & set up gnunet-update | ||
2126 | @c @subsection Download & set up gnunet-update | ||
2127 | |||
2128 | @c The following command will download a working version of gnunet-update | ||
2129 | @c with the subversion tool and import the public key which is needed for | ||
2130 | @c authentication: | ||
2131 | |||
2132 | @c @example | ||
2133 | @c svn checkout -r24905 https://gnunet.org/svn/gnunet-update ~/gnunet-update | ||
2134 | @c cd ~/gnunet-update | ||
2135 | @c gpg --keyserver "hkp://keys.gnupg.net" --recv-keys 7C613D78 | ||
2136 | @c @end example | ||
2137 | |||
2138 | @c @node Install GNUnet | ||
2139 | @c @subsection Install GNUnet | ||
2140 | |||
2141 | @c Download and install GNUnet binaries which can be found here and set | ||
2142 | @c library paths: | ||
2143 | |||
2144 | @c @example | ||
2145 | @c wget -P /tmp https://gnunet.org/install/packs/gnunet-0.9.4-`uname -m`.tgz | ||
2146 | @c ./bin/gnunet-update install /tmp/gnunet-0.9*.tgz ~ | ||
2147 | @c echo "PATH DEFAULT=$@{PATH@}:$HOME/bin" >> ~/.pam_environment | ||
2148 | @c echo -e "$@{HOME@}/lib\n$@{HOME@}/lib/gnunet-deps" | sudo tee \ | ||
2149 | @c /etc/ld.so.conf.d/gnunet.conf > /dev/null | ||
2150 | @c sudo ldconfig | ||
2151 | @c @end example | ||
2152 | |||
2153 | @c You may need to re-login once after executing these last commands | ||
2154 | |||
2155 | @c That's it, GNUnet is installed in your home directory now. GNUnet can be | ||
2156 | @c configured and afterwards started by executing: | ||
2157 | |||
2158 | @c @example | ||
2159 | @c gnunet-arm -s | ||
2160 | @c @end example | ||
2161 | |||
2162 | @node The graphical configuration interface | ||
2163 | @section The graphical configuration interface | ||
2164 | |||
2165 | If you also would like to use @command{gnunet-gtk} and | ||
2166 | @command{gnunet-setup} (highly recommended for beginners), do: | ||
2167 | |||
2168 | @example | ||
2169 | wget -P /tmp \ | ||
2170 | https://gnunet.org/install/packs/gnunet-0.9.4-gtk-0.9.4-`uname -m`.tgz | ||
2171 | sh ~/gnunet-update/bin/gnunet-update install /tmp/gnunet-*gtk*.tgz ~ | ||
2172 | sudo ldconfig | ||
2173 | @end example | ||
2174 | |||
2175 | Now you can run @command{gnunet-setup} for easy configuration of your | ||
2176 | GNUnet peer. | ||
2177 | |||
2178 | @menu | ||
2179 | * Configuring your peer:: | ||
2180 | * Configuring the Friend-to-Friend (F2F) mode:: | ||
2181 | * Configuring the hostlist to bootstrap:: | ||
2182 | * Configuration of the HOSTLIST proxy settings:: | ||
2183 | * Configuring your peer to provide a hostlist :: | ||
2184 | * Configuring the datastore:: | ||
2185 | * Configuring the MySQL database:: | ||
2186 | * Reasons for using MySQL:: | ||
2187 | * Reasons for not using MySQL:: | ||
2188 | * Setup Instructions:: | ||
2189 | * Testing:: | ||
2190 | * Performance Tuning:: | ||
2191 | * Setup for running Testcases:: | ||
2192 | * Configuring the Postgres database:: | ||
2193 | * Reasons to use Postgres:: | ||
2194 | * Reasons not to use Postgres:: | ||
2195 | * Manual setup instructions:: | ||
2196 | * Testing the setup manually:: | ||
2197 | * Configuring the datacache:: | ||
2198 | * Configuring the file-sharing service:: | ||
2199 | * Configuring logging:: | ||
2200 | * Configuring the transport service and plugins:: | ||
2201 | * Configuring the wlan transport plugin:: | ||
2202 | * Configuring HTTP(S) reverse proxy functionality using Apache or nginx:: | ||
2203 | * Blacklisting peers:: | ||
2204 | * Configuration of the HTTP and HTTPS transport plugins:: | ||
2205 | * Configuring the GNU Name System:: | ||
2206 | * Configuring the GNUnet VPN:: | ||
2207 | * Bandwidth Configuration:: | ||
2208 | * Configuring NAT:: | ||
2209 | * Peer configuration for distributions:: | ||
2210 | @end menu | ||
2211 | |||
2212 | @node Configuring your peer | ||
2213 | @subsection Configuring your peer | ||
2214 | |||
2215 | This chapter will describe the various configuration options in GNUnet. | ||
2216 | |||
2217 | The easiest way to configure your peer is to use the | ||
2218 | @command{gnunet-setup} tool. | ||
2219 | @command{gnunet-setup} is part of the @command{gnunet-gtk} | ||
2220 | application. You might have to install it separately. | ||
2221 | |||
2222 | Many of the specific sections from this chapter actually are linked from | ||
2223 | within @command{gnunet-setup} to help you while using the setup tool. | ||
2224 | |||
2225 | While you can also configure your peer by editing the configuration | ||
2226 | file by hand, this is not recommended for anyone except for developers | ||
2227 | as it requires a more in-depth understanding of the configuration files | ||
2228 | and internal dependencies of GNUnet. | ||
2229 | |||
2230 | @node Configuring the Friend-to-Friend (F2F) mode | ||
2231 | @subsection Configuring the Friend-to-Friend (F2F) mode | ||
2232 | |||
2233 | GNUnet knows three basic modes of operation: | ||
2234 | @itemize @bullet | ||
2235 | @item In standard "peer-to-peer" mode, | ||
2236 | your peer will connect to any peer. | ||
2237 | @item In the pure "friend-to-friend" | ||
2238 | mode, your peer will ONLY connect to peers from a list of friends | ||
2239 | specified in the configuration. | ||
2240 | @item Finally, in mixed mode, | ||
2241 | GNUnet will only connect to arbitrary peers if it | ||
2242 | has at least a specified number of connections to friends. | ||
2243 | @end itemize | ||
2244 | |||
2245 | When configuring any of the F2F ("friend-to-friend") modes, | ||
2246 | you first need to create a file with the peer identities | ||
2247 | of your friends. Ask your friends to run | ||
2248 | |||
2249 | @example | ||
2250 | $ gnunet-peerinfo -sq | ||
2251 | @end example | ||
2252 | |||
2253 | @noindent | ||
2254 | The resulting output of this command needs to be added to your | ||
2255 | @file{friends} file, which is simply a plain text file with one line | ||
2256 | per friend with the output from the above command. | ||
2257 | |||
2258 | You then specify the location of your @file{friends} file in the | ||
2259 | @code{FRIENDS} option of the "topology" section. | ||
2260 | |||
2261 | Once you have created the @file{friends} file, you can tell GNUnet to only | ||
2262 | connect to your friends by setting the @code{FRIENDS-ONLY} option | ||
2263 | (again in the "topology" section) to YES. | ||
2264 | |||
2265 | If you want to run in mixed-mode, set "FRIENDS-ONLY" to NO and configure a | ||
2266 | minimum number of friends to have (before connecting to arbitrary peers) | ||
2267 | under the "MINIMUM-FRIENDS" option. | ||
2268 | |||
2269 | If you want to operate in normal P2P-only mode, simply set | ||
2270 | @code{MINIMUM-FRIENDS} to zero and @code{FRIENDS_ONLY} to NO. | ||
2271 | This is the default. | ||
2272 | |||
2273 | @node Configuring the hostlist to bootstrap | ||
2274 | @subsection Configuring the hostlist to bootstrap | ||
2275 | |||
2276 | After installing the software you need to get connected to the GNUnet | ||
2277 | network. The configuration file included in your download is already | ||
2278 | configured to connect you to the GNUnet network. | ||
2279 | In this section the relevant configuration settings are explained. | ||
2280 | |||
2281 | To get an initial connection to the GNUnet network and to get to know | ||
2282 | peers already connected to the network you can use the so called | ||
2283 | "bootstrap servers". | ||
2284 | These servers can give you a list of peers connected to the network. | ||
2285 | To use these bootstrap servers you have to configure the hostlist daemon | ||
2286 | to activate bootstrapping. | ||
2287 | |||
2288 | To activate bootstrapping, edit the @code{[hostlist]}-section in your | ||
2289 | configuration file. You have to set the argument @command{-b} in the | ||
2290 | options line: | ||
2291 | |||
2292 | @example | ||
2293 | [hostlist] | ||
2294 | OPTIONS = -b | ||
2295 | @end example | ||
2296 | |||
2297 | Additionally you have to specify which server you want to use. | ||
2298 | The default bootstrapping server is | ||
2299 | "@uref{http://v10.gnunet.org/hostlist, http://v10.gnunet.org/hostlist}". | ||
2300 | [^] To set the server you have to edit the line "SERVERS" in the hostlist | ||
2301 | section. To use the default server you should set the lines to | ||
2302 | |||
2303 | @example | ||
2304 | SERVERS = http://v10.gnunet.org/hostlist [^] | ||
2305 | @end example | ||
2306 | |||
2307 | @noindent | ||
2308 | To use bootstrapping your configuration file should include these lines: | ||
2309 | |||
2310 | @example | ||
2311 | [hostlist] | ||
2312 | OPTIONS = -b | ||
2313 | SERVERS = http://v10.gnunet.org/hostlist [^] | ||
2314 | @end example | ||
2315 | |||
2316 | @noindent | ||
2317 | Besides using bootstrap servers you can configure your GNUnet peer to | ||
2318 | recieve hostlist advertisements. | ||
2319 | Peers offering hostlists to other peers can send advertisement messages | ||
2320 | to peers that connect to them. If you configure your peer to receive these | ||
2321 | messages, your peer can download these lists and connect to the peers | ||
2322 | included. These lists are persistent, which means that they are saved to | ||
2323 | your hard disk regularly and are loaded during startup. | ||
2324 | |||
2325 | To activate hostlist learning you have to add the @command{-e} | ||
2326 | switch to the @code{OPTIONS} line in the hostlist section: | ||
2327 | |||
2328 | @example | ||
2329 | [hostlist] | ||
2330 | OPTIONS = -b -e | ||
2331 | @end example | ||
2332 | |||
2333 | @noindent | ||
2334 | Furthermore you can specify in which file the lists are saved. | ||
2335 | To save the lists in the file @file{hostlists.file} just add the line: | ||
2336 | |||
2337 | @example | ||
2338 | HOSTLISTFILE = hostlists.file | ||
2339 | @end example | ||
2340 | |||
2341 | @noindent | ||
2342 | Best practice is to activate both bootstrapping and hostlist learning. | ||
2343 | So your configuration file should include these lines: | ||
2344 | |||
2345 | @example | ||
2346 | [hostlist] | ||
2347 | OPTIONS = -b -e | ||
2348 | HTTPPORT = 8080 | ||
2349 | SERVERS = http://v10.gnunet.org/hostlist [^] | ||
2350 | HOSTLISTFILE = $SERVICEHOME/hostlists.file | ||
2351 | @end example | ||
2352 | |||
2353 | @node Configuration of the HOSTLIST proxy settings | ||
2354 | @subsection Configuration of the HOSTLIST proxy settings | ||
2355 | |||
2356 | The hostlist client can be configured to use a proxy to connect to the | ||
2357 | hostlist server. | ||
2358 | This functionality can be configured in the configuration file directly | ||
2359 | or using the @command{gnunet-setup} tool. | ||
2360 | |||
2361 | The hostlist client supports the following proxy types at the moment: | ||
2362 | |||
2363 | @itemize @bullet | ||
2364 | @item HTTP and HTTP 1.0 only proxy | ||
2365 | @item SOCKS 4/4a/5/5 with hostname | ||
2366 | @end itemize | ||
2367 | |||
2368 | In addition authentication at the proxy with username and password can be | ||
2369 | configured. | ||
2370 | |||
2371 | To configure proxy support for the hostlist client in the | ||
2372 | @command{gnunet-setup} tool, select the "hostlist" tab and select | ||
2373 | the appropriate proxy type. | ||
2374 | The hostname or IP address (including port if required) has to be entered | ||
2375 | in the "Proxy hostname" textbox. If required, enter username and password | ||
2376 | in the "Proxy username" and "Proxy password" boxes. | ||
2377 | Be aware that this information will be stored in the configuration in | ||
2378 | plain text (TODO: Add explanation and generalize the part in Chapter 3.6 | ||
2379 | about the encrypted home). | ||
2380 | |||
2381 | To provide these options directly in the configuration, you can | ||
2382 | enter the following settings in the @code{[hostlist]} section of | ||
2383 | the configuration: | ||
2384 | |||
2385 | @example | ||
2386 | # Type of proxy server, | ||
2387 | # Valid values: HTTP, HTTP_1_0, SOCKS4, SOCKS5, SOCKS4A, SOCKS5_HOSTNAME | ||
2388 | # Default: HTTP | ||
2389 | # PROXY_TYPE = HTTP | ||
2390 | |||
2391 | # Hostname or IP of proxy server | ||
2392 | # PROXY = | ||
2393 | # User name for proxy server | ||
2394 | # PROXY_USERNAME = | ||
2395 | # User password for proxy server | ||
2396 | # PROXY_PASSWORD = | ||
2397 | @end example | ||
2398 | |||
2399 | @node Configuring your peer to provide a hostlist | ||
2400 | @subsection Configuring your peer to provide a hostlist | ||
2401 | |||
2402 | If you operate a peer permanently connected to GNUnet you can configure | ||
2403 | your peer to act as a hostlist server, providing other peers the list of | ||
2404 | peers known to him. | ||
2405 | |||
2406 | Your server can act as a bootstrap server and peers needing to obtain a | ||
2407 | list of peers can contact it to download this list. | ||
2408 | To download this hostlist the peer uses HTTP. | ||
2409 | For this reason you have to build your peer with libgnurl (or libcurl) | ||
2410 | and microhttpd support. | ||
2411 | How you build your peer with these options can be found here: | ||
2412 | @xref{Generic installation instructions}. | ||
2413 | |||
2414 | To configure your peer to act as a bootstrap server you have to add the | ||
2415 | @command{-p} option to @code{OPTIONS} in the @code{[hostlist]} section | ||
2416 | of your configuration file. | ||
2417 | Besides that you have to specify a port number for the http server. | ||
2418 | In conclusion you have to add the following lines: | ||
2419 | |||
2420 | @example | ||
2421 | [hostlist] | ||
2422 | HTTPPORT = 12980 | ||
2423 | OPTIONS = -p | ||
2424 | @end example | ||
2425 | |||
2426 | @noindent | ||
2427 | If your peer acts as a bootstrap server other peers should know about | ||
2428 | that. You can advertise the hostlist your are providing to other peers. | ||
2429 | Peers connecting to your peer will get a message containing an | ||
2430 | advertisement for your hostlist and the URL where it can be downloaded. | ||
2431 | If this peer is in learning mode, it will test the hostlist and, in the | ||
2432 | case it can obtain the list successfully, it will save it for | ||
2433 | bootstrapping. | ||
2434 | |||
2435 | To activate hostlist advertisement on your peer, you have to set the | ||
2436 | following lines in your configuration file: | ||
2437 | |||
2438 | @example | ||
2439 | [hostlist] | ||
2440 | EXTERNAL_DNS_NAME = example.org | ||
2441 | HTTPPORT = 12981 | ||
2442 | OPTIONS = -p -a | ||
2443 | @end example | ||
2444 | |||
2445 | @noindent | ||
2446 | With this configuration your peer will a act as a bootstrap server and | ||
2447 | advertise this hostlist to other peers connecting to it. | ||
2448 | The URL used to download the list will be | ||
2449 | @code{@uref{http://example.org:12981/, http://example.org:12981/}}. | ||
2450 | |||
2451 | Please notice: | ||
2452 | |||
2453 | @itemize @bullet | ||
2454 | @item The hostlist is @b{not} human readable, so you should not try to | ||
2455 | download it using your webbrowser. Just point your GNUnet peer to the | ||
2456 | address! | ||
2457 | @item Advertising without providing a hostlist does not make sense and | ||
2458 | will not work. | ||
2459 | @end itemize | ||
2460 | |||
2461 | @node Configuring the datastore | ||
2462 | @subsection Configuring the datastore | ||
2463 | |||
2464 | The datastore is what GNUnet uses for long-term storage of file-sharing | ||
2465 | data. Note that long-term does not mean 'forever' since content does have | ||
2466 | an expiration date, and of course storage space is finite (and hence | ||
2467 | sometimes content may have to be discarded). | ||
2468 | |||
2469 | Use the @code{QUOTA} option to specify how many bytes of storage space | ||
2470 | you are willing to dedicate to GNUnet. | ||
2471 | |||
2472 | In addition to specifying the maximum space GNUnet is allowed to use for | ||
2473 | the datastore, you need to specify which database GNUnet should use to do | ||
2474 | so. Currently, you have the choice between sqLite, MySQL and Postgres. | ||
2475 | |||
2476 | @node Configuring the MySQL database | ||
2477 | @subsection Configuring the MySQL database | ||
2478 | |||
2479 | This section describes how to setup the MySQL database for GNUnet. | ||
2480 | |||
2481 | Note that the mysql plugin does NOT work with mysql before 4.1 since we | ||
2482 | need prepared statements. | ||
2483 | We are generally testing the code against MySQL 5.1 at this point. | ||
2484 | |||
2485 | @node Reasons for using MySQL | ||
2486 | @subsection Reasons for using MySQL | ||
2487 | |||
2488 | @itemize @bullet | ||
2489 | |||
2490 | @item On up-to-date hardware wher | ||
2491 | mysql can be used comfortably, this module | ||
2492 | will have better performance than the other database choices (according | ||
2493 | to our tests). | ||
2494 | |||
2495 | @item Its often possible to recover the mysql database from internal | ||
2496 | inconsistencies. Some of the other databases do not support repair. | ||
2497 | @end itemize | ||
2498 | |||
2499 | @node Reasons for not using MySQL | ||
2500 | @subsection Reasons for not using MySQL | ||
2501 | |||
2502 | @itemize @bullet | ||
2503 | @item Memory usage (likely not an issue if you have more than 1 GB) | ||
2504 | @item Complex manual setup | ||
2505 | @end itemize | ||
2506 | |||
2507 | @node Setup Instructions | ||
2508 | @subsection Setup Instructions | ||
2509 | |||
2510 | @itemize @bullet | ||
2511 | |||
2512 | @item In @file{gnunet.conf} set in section @code{DATASTORE} the value for | ||
2513 | @code{DATABASE} to @code{mysql}. | ||
2514 | |||
2515 | @item Access mysql as root: | ||
2516 | |||
2517 | @example | ||
2518 | $ mysql -u root -p | ||
2519 | @end example | ||
2520 | |||
2521 | @noindent | ||
2522 | and issue the following commands, replacing $USER with the username | ||
2523 | that will be running @command{gnunet-arm} (so typically "gnunet"): | ||
2524 | |||
2525 | @example | ||
2526 | CREATE DATABASE gnunet; | ||
2527 | GRANT select,insert,update,delete,create,alter,drop,create \ | ||
2528 | temporary tables ON gnunet.* TO $USER@@localhost; | ||
2529 | SET PASSWORD FOR $USER@@localhost=PASSWORD('$the_password_you_like'); | ||
2530 | FLUSH PRIVILEGES; | ||
2531 | @end example | ||
2532 | |||
2533 | @item | ||
2534 | In the $HOME directory of $USER, create a @file{.my.cnf} file with the | ||
2535 | following lines | ||
2536 | |||
2537 | @example | ||
2538 | [client] | ||
2539 | user=$USER | ||
2540 | password=$the_password_you_like | ||
2541 | @end example | ||
2542 | |||
2543 | @end itemize | ||
2544 | |||
2545 | Thats it. Note that @file{.my.cnf} file is a slight security risk unless | ||
2546 | its on a safe partition. The @file{$HOME/.my.cnf} can of course be | ||
2547 | a symbolic link. | ||
2548 | Luckily $USER has only priviledges to mess up GNUnet's tables, | ||
2549 | which should be pretty harmless. | ||
2550 | |||
2551 | @node Testing | ||
2552 | @subsection Testing | ||
2553 | |||
2554 | You should briefly try if the database connection works. First, login | ||
2555 | as $USER. Then use: | ||
2556 | |||
2557 | @example | ||
2558 | $ mysql -u $USER | ||
2559 | mysql> use gnunet; | ||
2560 | @end example | ||
2561 | |||
2562 | @noindent | ||
2563 | If you get the message | ||
2564 | |||
2565 | @example | ||
2566 | Database changed | ||
2567 | @end example | ||
2568 | |||
2569 | @noindent | ||
2570 | it probably works. | ||
2571 | |||
2572 | If you get | ||
2573 | |||
2574 | @example | ||
2575 | ERROR 2002: Can't connect to local MySQL server | ||
2576 | through socket '/tmp/mysql.sock' (2) | ||
2577 | @end example | ||
2578 | |||
2579 | @noindent | ||
2580 | it may be resolvable by | ||
2581 | |||
2582 | @example | ||
2583 | ln -s /var/run/mysqld/mysqld.sock /tmp/mysql.sock | ||
2584 | @end example | ||
2585 | |||
2586 | @noindent | ||
2587 | so there may be some additional trouble depending on your mysql setup. | ||
2588 | |||
2589 | @node Performance Tuning | ||
2590 | @subsection Performance Tuning | ||
2591 | |||
2592 | For GNUnet, you probably want to set the option | ||
2593 | |||
2594 | @example | ||
2595 | innodb_flush_log_at_trx_commit = 0 | ||
2596 | @end example | ||
2597 | |||
2598 | @noindent | ||
2599 | for a rather dramatic boost in MySQL performance. However, this reduces | ||
2600 | the "safety" of your database as with this options you may loose | ||
2601 | transactions during a power outage. | ||
2602 | While this is totally harmless for GNUnet, the option applies to all | ||
2603 | applications using MySQL. So you should set it if (and only if) GNUnet is | ||
2604 | the only application on your system using MySQL. | ||
2605 | |||
2606 | @node Setup for running Testcases | ||
2607 | @subsection Setup for running Testcases | ||
2608 | |||
2609 | If you want to run the testcases, you must create a second database | ||
2610 | "gnunetcheck" with the same username and password. This database will | ||
2611 | then be used for testing (@command{make check}). | ||
2612 | |||
2613 | @node Configuring the Postgres database | ||
2614 | @subsection Configuring the Postgres database | ||
2615 | |||
2616 | This text describes how to setup the Postgres database for GNUnet. | ||
2617 | |||
2618 | This Postgres plugin was developed for Postgres 8.3 but might work for | ||
2619 | earlier versions as well. | ||
2620 | |||
2621 | @node Reasons to use Postgres | ||
2622 | @subsection Reasons to use Postgres | ||
2623 | |||
2624 | @itemize @bullet | ||
2625 | @item Easier to setup than MySQL | ||
2626 | @item Real database | ||
2627 | @end itemize | ||
2628 | |||
2629 | @node Reasons not to use Postgres | ||
2630 | @subsection Reasons not to use Postgres | ||
2631 | |||
2632 | @itemize @bullet | ||
2633 | @item Quite slow | ||
2634 | @item Still some manual setup required | ||
2635 | @end itemize | ||
2636 | |||
2637 | @node Manual setup instructions | ||
2638 | @subsection Manual setup instructions | ||
2639 | |||
2640 | @itemize @bullet | ||
2641 | @item In @file{gnunet.conf} set in section @code{DATASTORE} the value for | ||
2642 | @code{DATABASE} to @code{postgres}. | ||
2643 | @item Access Postgres to create a user: | ||
2644 | |||
2645 | @table @asis | ||
2646 | @item with Postgres 8.x, use: | ||
2647 | |||
2648 | @example | ||
2649 | # su - postgres | ||
2650 | $ createuser | ||
2651 | @end example | ||
2652 | |||
2653 | @noindent | ||
2654 | and enter the name of the user running GNUnet for the role interactively. | ||
2655 | Then, when prompted, do not set it to superuser, allow the creation of | ||
2656 | databases, and do not allow the creation of new roles. | ||
2657 | |||
2658 | @item with Postgres 9.x, use: | ||
2659 | |||
2660 | @example | ||
2661 | # su - postgres | ||
2662 | $ createuser -d $GNUNET_USER | ||
2663 | @end example | ||
2664 | |||
2665 | @noindent | ||
2666 | where $GNUNET_USER is the name of the user running GNUnet. | ||
2667 | |||
2668 | @end table | ||
2669 | |||
2670 | |||
2671 | @item | ||
2672 | As that user (so typically as user "gnunet"), create a database (or two): | ||
2673 | |||
2674 | @example | ||
2675 | $ createdb gnunet | ||
2676 | # this way you can run "make check" | ||
2677 | $ createdb gnunetcheck | ||
2678 | @end example | ||
2679 | |||
2680 | @end itemize | ||
2681 | |||
2682 | Now you should be able to start @code{gnunet-arm}. | ||
2683 | |||
2684 | @node Testing the setup manually | ||
2685 | @subsection Testing the setup manually | ||
2686 | |||
2687 | You may want to try if the database connection works. First, again login | ||
2688 | as the user who will run @command{gnunet-arm}. Then use: | ||
2689 | |||
2690 | @example | ||
2691 | $ psql gnunet # or gnunetcheck | ||
2692 | gnunet=> \dt | ||
2693 | @end example | ||
2694 | |||
2695 | @noindent | ||
2696 | If, after you have started @command{gnunet-arm} at least once, you get | ||
2697 | a @code{gn090} table here, it probably works. | ||
2698 | |||
2699 | @node Configuring the datacache | ||
2700 | @subsection Configuring the datacache | ||
2701 | @c %**end of header | ||
2702 | |||
2703 | The datacache is what GNUnet uses for storing temporary data. This data is | ||
2704 | expected to be wiped completely each time GNUnet is restarted (or the | ||
2705 | system is rebooted). | ||
2706 | |||
2707 | You need to specify how many bytes GNUnet is allowed to use for the | ||
2708 | datacache using the @code{QUOTA} option in the section @code{[dhtcache]}. | ||
2709 | Furthermore, you need to specify which database backend should be used to | ||
2710 | store the data. Currently, you have the choice between | ||
2711 | sqLite, MySQL and Postgres. | ||
2712 | |||
2713 | @node Configuring the file-sharing service | ||
2714 | @subsection Configuring the file-sharing service | ||
2715 | |||
2716 | In order to use GNUnet for file-sharing, you first need to make sure | ||
2717 | that the file-sharing service is loaded. | ||
2718 | This is done by setting the @code{AUTOSTART} option in | ||
2719 | section @code{[fs]} to "YES". Alternatively, you can run | ||
2720 | |||
2721 | @example | ||
2722 | $ gnunet-arm -i fs | ||
2723 | @end example | ||
2724 | |||
2725 | @noindent | ||
2726 | to start the file-sharing service by hand. | ||
2727 | |||
2728 | Except for configuring the database and the datacache the only important | ||
2729 | option for file-sharing is content migration. | ||
2730 | |||
2731 | Content migration allows your peer to cache content from other peers as | ||
2732 | well as send out content stored on your system without explicit requests. | ||
2733 | This content replication has positive and negative impacts on both system | ||
2734 | performance and privacy. | ||
2735 | |||
2736 | FIXME: discuss the trade-offs. Here is some older text about it... | ||
2737 | |||
2738 | Setting this option to YES allows gnunetd to migrate data to the local | ||
2739 | machine. Setting this option to YES is highly recommended for efficiency. | ||
2740 | Its also the default. If you set this value to YES, GNUnet will store | ||
2741 | content on your machine that you cannot decrypt. | ||
2742 | While this may protect you from liability if the judge is sane, it may | ||
2743 | not (IANAL). If you put illegal content on your machine yourself, setting | ||
2744 | this option to YES will probably increase your chances to get away with it | ||
2745 | since you can plausibly deny that you inserted the content. | ||
2746 | Note that in either case, your anonymity would have to be broken first | ||
2747 | (which may be possible depending on the size of the GNUnet network and the | ||
2748 | strength of the adversary). | ||
2749 | |||
2750 | @node Configuring logging | ||
2751 | @subsection Configuring logging | ||
2752 | |||
2753 | Logging in GNUnet 0.9.0 is controlled via the "-L" and "-l" options. | ||
2754 | Using @code{-L}, a log level can be specified. With log level | ||
2755 | @code{ERROR} only serious errors are logged. | ||
2756 | The default log level is @code{WARNING} which causes anything of | ||
2757 | concern to be logged. | ||
2758 | Log level @code{INFO} can be used to log anything that might be | ||
2759 | interesting information whereas | ||
2760 | @code{DEBUG} can be used by developers to log debugging messages | ||
2761 | (but you need to run @code{./configure} with | ||
2762 | @code{--enable-logging=verbose} to get them compiled). | ||
2763 | The @code{-l} option is used to specify the log file. | ||
2764 | |||
2765 | Since most GNUnet services are managed by @code{gnunet-arm}, using the | ||
2766 | @code{-l} or @code{-L} options directly is not possible. | ||
2767 | Instead, they can be specified using the @code{OPTIONS} configuration | ||
2768 | value in the respective section for the respective service. | ||
2769 | In order to enable logging globally without editing the @code{OPTIONS} | ||
2770 | values for each service, @command{gnunet-arm} supports a | ||
2771 | @code{GLOBAL_POSTFIX} option. | ||
2772 | The value specified here is given as an extra option to all services for | ||
2773 | which the configuration does contain a service-specific @code{OPTIONS} | ||
2774 | field. | ||
2775 | |||
2776 | @code{GLOBAL_POSTFIX} can contain the special sequence "@{@}" which | ||
2777 | is replaced by the name of the service that is being started. | ||
2778 | Furthermore, @code{GLOBAL_POSTFIX} is special in that sequences | ||
2779 | starting with "$" anywhere in the string are expanded (according | ||
2780 | to options in @code{PATHS}); this expansion otherwise is | ||
2781 | only happening for filenames and then the "$" must be the | ||
2782 | first character in the option. Both of these restrictions do | ||
2783 | not apply to @code{GLOBAL_POSTFIX}. | ||
2784 | Note that specifying @code{%} anywhere in the @code{GLOBAL_POSTFIX} | ||
2785 | disables both of these features. | ||
2786 | |||
2787 | In summary, in order to get all services to log at level | ||
2788 | @code{INFO} to log-files called @code{SERVICENAME-logs}, the | ||
2789 | following global prefix should be used: | ||
2790 | |||
2791 | @example | ||
2792 | GLOBAL_POSTFIX = -l $SERVICEHOME/@{@}-logs -L INFO | ||
2793 | @end example | ||
2794 | |||
2795 | @node Configuring the transport service and plugins | ||
2796 | @subsection Configuring the transport service and plugins | ||
2797 | |||
2798 | The transport service in GNUnet is responsible to maintain basic | ||
2799 | connectivity to other peers. | ||
2800 | Besides initiating and keeping connections alive it is also responsible | ||
2801 | for address validation. | ||
2802 | |||
2803 | The GNUnet transport supports more than one transport protocol. | ||
2804 | These protocols are configured together with the transport service. | ||
2805 | |||
2806 | The configuration section for the transport service itself is quite | ||
2807 | similar to all the other services | ||
2808 | |||
2809 | @example | ||
2810 | AUTOSTART = YES | ||
2811 | @@UNIXONLY@@ PORT = 2091 | ||
2812 | HOSTNAME = localhost | ||
2813 | HOME = $SERVICEHOME | ||
2814 | CONFIG = $DEFAULTCONFIG | ||
2815 | BINARY = gnunet-service-transport | ||
2816 | #PREFIX = valgrind | ||
2817 | NEIGHBOUR_LIMIT = 50 | ||
2818 | ACCEPT_FROM = 127.0.0.1; | ||
2819 | ACCEPT_FROM6 = ::1; | ||
2820 | PLUGINS = tcp udp | ||
2821 | UNIXPATH = /tmp/gnunet-service-transport.sock | ||
2822 | @end example | ||
2823 | |||
2824 | Different are the settings for the plugins to load @code{PLUGINS}. | ||
2825 | The first setting specifies which transport plugins to load. | ||
2826 | |||
2827 | @itemize @bullet | ||
2828 | @item transport-unix | ||
2829 | A plugin for local only communication with UNIX domain sockets. Used for | ||
2830 | testing and available on unix systems only. Just set the port | ||
2831 | |||
2832 | @example | ||
2833 | [transport-unix] | ||
2834 | PORT = 22086 | ||
2835 | TESTING_IGNORE_KEYS = ACCEPT_FROM; | ||
2836 | @end example | ||
2837 | |||
2838 | @item transport-tcp | ||
2839 | A plugin for communication with TCP. Set port to 0 for client mode with | ||
2840 | outbound only connections | ||
2841 | |||
2842 | @example | ||
2843 | [transport-tcp] | ||
2844 | # Use 0 to ONLY advertise as a peer behind NAT (no port binding) | ||
2845 | PORT = 2086 | ||
2846 | ADVERTISED_PORT = 2086 | ||
2847 | TESTING_IGNORE_KEYS = ACCEPT_FROM; | ||
2848 | # Maximum number of open TCP connections allowed | ||
2849 | MAX_CONNECTIONS = 128 | ||
2850 | @end example | ||
2851 | |||
2852 | @item transport-udp | ||
2853 | A plugin for communication with UDP. Supports peer discovery using | ||
2854 | broadcasts. | ||
2855 | |||
2856 | @example | ||
2857 | [transport-udp] | ||
2858 | PORT = 2086 | ||
2859 | BROADCAST = YES | ||
2860 | BROADCAST_INTERVAL = 30 s | ||
2861 | MAX_BPS = 1000000 | ||
2862 | TESTING_IGNORE_KEYS = ACCEPT_FROM; | ||
2863 | @end example | ||
2864 | |||
2865 | @item transport-http | ||
2866 | HTTP and HTTPS support is split in two part: a client plugin initiating | ||
2867 | outbound connections and a server part accepting connections from the | ||
2868 | client. The client plugin just takes the maximum number of connections as | ||
2869 | an argument. | ||
2870 | |||
2871 | @example | ||
2872 | [transport-http_client] | ||
2873 | MAX_CONNECTIONS = 128 | ||
2874 | TESTING_IGNORE_KEYS = ACCEPT_FROM; | ||
2875 | @end example | ||
2876 | |||
2877 | @example | ||
2878 | [transport-https_client] | ||
2879 | MAX_CONNECTIONS = 128 | ||
2880 | TESTING_IGNORE_KEYS = ACCEPT_FROM; | ||
2881 | @end example | ||
2882 | |||
2883 | @noindent | ||
2884 | The server has a port configured and the maximum nunber of connections. | ||
2885 | The HTTPS part has two files with the certificate key and the certificate | ||
2886 | file. | ||
2887 | |||
2888 | The server plugin supports reverse proxies, so a external hostname can be | ||
2889 | set using the @code{EXTERNAL_HOSTNAME} setting. | ||
2890 | The webserver under this address should forward the request to the peer | ||
2891 | and the configure port. | ||
2892 | |||
2893 | @example | ||
2894 | [transport-http_server] | ||
2895 | EXTERNAL_HOSTNAME = fulcrum.net.in.tum.de/gnunet | ||
2896 | PORT = 1080 | ||
2897 | MAX_CONNECTIONS = 128 | ||
2898 | TESTING_IGNORE_KEYS = ACCEPT_FROM; | ||
2899 | @end example | ||
2900 | |||
2901 | @example | ||
2902 | [transport-https_server] | ||
2903 | PORT = 4433 | ||
2904 | CRYPTO_INIT = NORMAL | ||
2905 | KEY_FILE = https.key | ||
2906 | CERT_FILE = https.cert | ||
2907 | MAX_CONNECTIONS = 128 | ||
2908 | TESTING_IGNORE_KEYS = ACCEPT_FROM; | ||
2909 | @end example | ||
2910 | |||
2911 | @item transport-wlan | ||
2912 | |||
2913 | The next section describes how to setup the WLAN plugin, | ||
2914 | so here only the settings. Just specify the interface to use: | ||
2915 | |||
2916 | @example | ||
2917 | [transport-wlan] | ||
2918 | # Name of the interface in monitor mode (typically monX) | ||
2919 | INTERFACE = mon0 | ||
2920 | # Real hardware, no testing | ||
2921 | TESTMODE = 0 | ||
2922 | TESTING_IGNORE_KEYS = ACCEPT_FROM; | ||
2923 | @end example | ||
2924 | @end itemize | ||
2925 | |||
2926 | @node Configuring the wlan transport plugin | ||
2927 | @subsection Configuring the wlan transport plugin | ||
2928 | |||
2929 | The wlan transport plugin enables GNUnet to send and to receive data on a | ||
2930 | wlan interface. | ||
2931 | It has not to be connected to a wlan network as long as sender and | ||
2932 | receiver are on the same channel. This enables you to get connection to | ||
2933 | GNUnet where no internet access is possible, for example during | ||
2934 | catastrophes or when censorship cuts you off from the internet. | ||
2935 | |||
2936 | |||
2937 | @menu | ||
2938 | * Requirements for the WLAN plugin:: | ||
2939 | * Configuration:: | ||
2940 | * Before starting GNUnet:: | ||
2941 | * Limitations and known bugs:: | ||
2942 | @end menu | ||
2943 | |||
2944 | |||
2945 | @node Requirements for the WLAN plugin | ||
2946 | @subsubsection Requirements for the WLAN plugin | ||
2947 | |||
2948 | @itemize @bullet | ||
2949 | |||
2950 | @item wlan network card with monitor support and packet injection | ||
2951 | (see @uref{http://www.aircrack-ng.org/, aircrack-ng.org}) | ||
2952 | |||
2953 | @item Linux kernel with mac80211 stack, introduced in 2.6.22, tested with | ||
2954 | 2.6.35 and 2.6.38 | ||
2955 | |||
2956 | @item Wlantools to create the a monitor interface, tested with airmon-ng | ||
2957 | of the aircrack-ng package | ||
2958 | @end itemize | ||
2959 | |||
2960 | @node Configuration | ||
2961 | @subsubsection Configuration | ||
2962 | |||
2963 | There are the following options for the wlan plugin (they should be like | ||
2964 | this in your default config file, you only need to adjust them if the | ||
2965 | values are incorrect for your system) | ||
2966 | |||
2967 | @example | ||
2968 | # section for the wlan transport plugin | ||
2969 | [transport-wlan] | ||
2970 | # interface to use, more information in the | ||
2971 | # "Before starting GNUnet" section of the handbook. | ||
2972 | INTERFACE = mon0 | ||
2973 | # testmode for developers: | ||
2974 | # 0 use wlan interface, | ||
2975 | #1 or 2 use loopback driver for tests 1 = server, 2 = client | ||
2976 | TESTMODE = 0 | ||
2977 | @end example | ||
2978 | |||
2979 | @node Before starting GNUnet | ||
2980 | @subsubsection Before starting GNUnet | ||
2981 | |||
2982 | Before starting GNUnet, you have to make sure that your wlan interface is | ||
2983 | in monitor mode. | ||
2984 | One way to put the wlan interface into monitor mode (if your interface | ||
2985 | name is wlan0) is by executing: | ||
2986 | |||
2987 | @example | ||
2988 | sudo airmon-ng start wlan0 | ||
2989 | @end example | ||
2990 | |||
2991 | @noindent | ||
2992 | Here is an example what the result should look like: | ||
2993 | |||
2994 | @example | ||
2995 | Interface Chipset Driver | ||
2996 | wlan0 Intel 4965 a/b/g/n iwl4965 - [phy0] | ||
2997 | (monitor mode enabled on mon0) | ||
2998 | @end example | ||
2999 | |||
3000 | @noindent | ||
3001 | The monitor interface is mon0 is the one that you have to put into the | ||
3002 | configuration file. | ||
3003 | |||
3004 | @node Limitations and known bugs | ||
3005 | @subsubsection Limitations and known bugs | ||
3006 | |||
3007 | Wlan speed is at the maximum of 1 Mbit/s because support for choosing the | ||
3008 | wlan speed with packet injection was removed in newer kernels. | ||
3009 | Please pester the kernel developers about fixing this. | ||
3010 | |||
3011 | The interface channel depends on the wlan network that the card is | ||
3012 | connected to. If no connection has been made since the start of the | ||
3013 | computer, it is usually the first channel of the card. | ||
3014 | Peers will only find each other and communicate if they are on the same | ||
3015 | channel. Channels must be set manually, i.e. using: | ||
3016 | |||
3017 | @example | ||
3018 | iwconfig wlan0 channel 1 | ||
3019 | @end example | ||
3020 | |||
3021 | @node Configuring HTTP(S) reverse proxy functionality using Apache or nginx | ||
3022 | @subsection Configuring HTTP(S) reverse proxy functionality using Apache or nginx | ||
3023 | |||
3024 | The HTTP plugin supports data transfer using reverse proxies. A reverse | ||
3025 | proxy forwards the HTTP request he receives with a certain URL to another | ||
3026 | webserver, here a GNUnet peer. | ||
3027 | |||
3028 | So if you have a running Apache or nginx webserver you can configure it to | ||
3029 | be a GNUnet reverse proxy. Especially if you have a well-known webiste | ||
3030 | this improves censorship resistance since it looks as normal surfing | ||
3031 | behaviour. | ||
3032 | |||
3033 | To do so, you have to do two things: | ||
3034 | |||
3035 | @itemize @bullet | ||
3036 | @item Configure your webserver to forward the GNUnet HTTP traffic | ||
3037 | @item Configure your GNUnet peer to announce the respective address | ||
3038 | @end itemize | ||
3039 | |||
3040 | As an example we want to use GNUnet peer running: | ||
3041 | |||
3042 | @itemize @bullet | ||
3043 | |||
3044 | @item HTTP server plugin on @code{gnunet.foo.org:1080} | ||
3045 | |||
3046 | @item HTTPS server plugin on @code{gnunet.foo.org:4433} | ||
3047 | |||
3048 | @item A apache or nginx webserver on | ||
3049 | @uref{http://www.foo.org/, http://www.foo.org:80/} | ||
3050 | |||
3051 | @item A apache or nginx webserver on https://www.foo.org:443/ | ||
3052 | @end itemize | ||
3053 | |||
3054 | And we want the webserver to accept GNUnet traffic under | ||
3055 | @code{http://www.foo.org/bar/}. The required steps are described here: | ||
3056 | |||
3057 | @menu | ||
3058 | * Reverse Proxy - Configure your Apache2 HTTP webserver:: | ||
3059 | * Reverse Proxy - Configure your Apache2 HTTPS webserver:: | ||
3060 | * Reverse Proxy - Configure your nginx HTTPS webserver:: | ||
3061 | * Reverse Proxy - Configure your nginx HTTP webserver:: | ||
3062 | * Reverse Proxy - Configure your GNUnet peer:: | ||
3063 | @end menu | ||
3064 | |||
3065 | @node Reverse Proxy - Configure your Apache2 HTTP webserver | ||
3066 | @subsubsection Reverse Proxy - Configure your Apache2 HTTP webserver | ||
3067 | |||
3068 | First of all you need mod_proxy installed. | ||
3069 | |||
3070 | Edit your webserver configuration. Edit | ||
3071 | @code{/etc/apache2/apache2.conf} or the site-specific configuration file. | ||
3072 | |||
3073 | In the respective @code{server config},@code{virtual host} or | ||
3074 | @code{directory} section add the following lines: | ||
3075 | |||
3076 | @example | ||
3077 | ProxyTimeout 300 | ||
3078 | ProxyRequests Off | ||
3079 | <Location /bar/ > | ||
3080 | ProxyPass http://gnunet.foo.org:1080/ | ||
3081 | ProxyPassReverse http://gnunet.foo.org:1080/ | ||
3082 | </Location> | ||
3083 | @end example | ||
3084 | |||
3085 | @node Reverse Proxy - Configure your Apache2 HTTPS webserver | ||
3086 | @subsubsection Reverse Proxy - Configure your Apache2 HTTPS webserver | ||
3087 | |||
3088 | We assume that you already have an HTTPS server running, if not please | ||
3089 | check how to configure a HTTPS host. An easy to use example is the | ||
3090 | @file{apache2/sites-available/default-ssl} example configuration file. | ||
3091 | |||
3092 | In the respective HTTPS @code{server config},@code{virtual host} or | ||
3093 | @code{directory} section add the following lines: | ||
3094 | |||
3095 | @example | ||
3096 | SSLProxyEngine On | ||
3097 | ProxyTimeout 300 | ||
3098 | ProxyRequests Off | ||
3099 | <Location /bar/ > | ||
3100 | ProxyPass https://gnunet.foo.org:4433/ | ||
3101 | ProxyPassReverse https://gnunet.foo.org:4433/ | ||
3102 | </Location> | ||
3103 | @end example | ||
3104 | |||
3105 | @noindent | ||
3106 | More information about the apache mod_proxy configuration can be found | ||
3107 | here: @uref{http://httpd.apache.org/docs/2.2/mod/mod_proxy.html#proxypass} | ||
3108 | . | ||
3109 | |||
3110 | @node Reverse Proxy - Configure your nginx HTTPS webserver | ||
3111 | @subsubsection Reverse Proxy - Configure your nginx HTTPS webserver | ||
3112 | |||
3113 | Since nginx does not support chunked encoding, you first of all have to | ||
3114 | install @code{chunkin}: @uref{http://wiki.nginx.org/HttpChunkinModule}. | ||
3115 | |||
3116 | To enable chunkin add: | ||
3117 | |||
3118 | @example | ||
3119 | chunkin on; | ||
3120 | error_page 411 = @@my_411_error; | ||
3121 | location @@my_411_error @{ | ||
3122 | chunkin_resume; | ||
3123 | @} | ||
3124 | @end example | ||
3125 | |||
3126 | @noindent | ||
3127 | Edit your webserver configuration. Edit @file{/etc/nginx/nginx.conf} or | ||
3128 | the site-specific configuration file. | ||
3129 | |||
3130 | In the @code{server} section add: | ||
3131 | |||
3132 | @example | ||
3133 | location /bar/ | ||
3134 | @{ | ||
3135 | proxy_pass http://gnunet.foo.org:1080/; | ||
3136 | proxy_buffering off; | ||
3137 | proxy_connect_timeout 5; # more than http_server | ||
3138 | proxy_read_timeout 350; # 60 default, 300s is GNUnet's idle timeout | ||
3139 | proxy_http_version 1.1; # 1.0 default | ||
3140 | proxy_next_upstream error timeout invalid_header http_500 http_503 http_502 http_504; | ||
3141 | @} | ||
3142 | @end example | ||
3143 | |||
3144 | @node Reverse Proxy - Configure your nginx HTTP webserver | ||
3145 | @subsubsection Reverse Proxy - Configure your nginx HTTP webserver | ||
3146 | |||
3147 | Edit your webserver configuration. Edit @file{/etc/nginx/nginx.conf} or | ||
3148 | the site-specific configuration file. | ||
3149 | |||
3150 | In the @code{server} section add: | ||
3151 | |||
3152 | @example | ||
3153 | ssl_session_timeout 6m; | ||
3154 | location /bar/ | ||
3155 | @{ | ||
3156 | proxy_pass https://gnunet.foo.org:4433/; | ||
3157 | proxy_buffering off; | ||
3158 | proxy_connect_timeout 5; # more than http_server | ||
3159 | proxy_read_timeout 350; # 60 default, 300s is GNUnet's idle timeout | ||
3160 | proxy_http_version 1.1; # 1.0 default | ||
3161 | proxy_next_upstream error timeout invalid_header http_500 http_503 http_502 http_504; | ||
3162 | @} | ||
3163 | @end example | ||
3164 | |||
3165 | @node Reverse Proxy - Configure your GNUnet peer | ||
3166 | @subsubsection Reverse Proxy - Configure your GNUnet peer | ||
3167 | |||
3168 | To have your GNUnet peer announce the address, you have to specify the | ||
3169 | @code{EXTERNAL_HOSTNAME} option in the @code{[transport-http_server]} | ||
3170 | section: | ||
3171 | |||
3172 | @example | ||
3173 | [transport-http_server] | ||
3174 | EXTERNAL_HOSTNAME = http://www.foo.org/bar/ | ||
3175 | @end example | ||
3176 | |||
3177 | @noindent | ||
3178 | and/or @code{[transport-https_server]} section: | ||
3179 | |||
3180 | @example | ||
3181 | [transport-https_server] | ||
3182 | EXTERNAL_HOSTNAME = https://www.foo.org/bar/ | ||
3183 | @end example | ||
3184 | |||
3185 | @noindent | ||
3186 | Now restart your webserver and your peer... | ||
3187 | |||
3188 | @node Blacklisting peers | ||
3189 | @subsection Blacklisting peers | ||
3190 | |||
3191 | Transport service supports to deny connecting to a specific peer of to a | ||
3192 | specific peer with a specific transport plugin using te blacklisting | ||
3193 | component of transport service. With@ blacklisting it is possible to deny | ||
3194 | connections to specific peers of@ to use a specific plugin to a specific | ||
3195 | peer. Peers can be blacklisted using@ the configuration or a blacklist | ||
3196 | client can be asked. | ||
3197 | |||
3198 | To blacklist peers using the configuration you have to add a section to | ||
3199 | your configuration containing the peer id of the peer to blacklist and | ||
3200 | the plugin@ if required. | ||
3201 | |||
3202 | Examples: | ||
3203 | |||
3204 | To blacklist connections to P565... on peer AG2P... using tcp add: | ||
3205 | |||
3206 | @c FIXME: This is too long and produces errors in the pdf. | ||
3207 | @example | ||
3208 | [transport-blacklist AG2PHES1BARB9IJCPAMJTFPVJ5V3A72S3F2A8SBUB8DAQ2V0O3V8G6G2JU56FHGFOHMQVKBSQFV98TCGTC3RJ1NINP82G0RC00N1520] | ||
3209 | P565723JO1C2HSN6J29TAQ22MN6CI8HTMUU55T0FUQG4CMDGGEQ8UCNBKUMB94GC8R9G4FB2SF9LDOBAJ6AMINBP4JHHDD6L7VD801G = tcp | ||
3210 | @end example | ||
3211 | |||
3212 | To blacklist connections to P565... on peer AG2P... using all plugins add: | ||
3213 | |||
3214 | @example | ||
3215 | [transport-blacklist-AG2PHES1BARB9IJCPAMJTFPVJ5V3A72S3F2A8SBUB8DAQ2V0O3V8G6G2JU56FHGFOHMQVKBSQFV98TCGTC3RJ1NINP82G0RC00N1520] | ||
3216 | P565723JO1C2HSN6J29TAQ22MN6CI8HTMUU55T0FUQG4CMDGGEQ8UCNBKUMB94GC8R9G4FB2SF9LDOBAJ6AMINBP4JHHDD6L7VD801G = | ||
3217 | @end example | ||
3218 | |||
3219 | You can also add a blacklist client usign the blacklist API. On a | ||
3220 | blacklist check, blacklisting first checks internally if the peer is | ||
3221 | blacklisted and if not, it asks the blacklisting clients. Clients are | ||
3222 | asked if it is OK to connect to a peer ID, the plugin is omitted. | ||
3223 | |||
3224 | On blacklist check for (peer, plugin) | ||
3225 | @itemize @bullet | ||
3226 | @item Do we have a local blacklist entry for this peer and this plugin?@ | ||
3227 | @item YES: disallow connection@ | ||
3228 | @item Do we have a local blacklist entry for this peer and all plugins?@ | ||
3229 | @item YES: disallow connection@ | ||
3230 | @item Does one of the clients disallow?@ | ||
3231 | @item YES: disallow connection | ||
3232 | @end itemize | ||
3233 | |||
3234 | @node Configuration of the HTTP and HTTPS transport plugins | ||
3235 | @subsection Configuration of the HTTP and HTTPS transport plugins | ||
3236 | |||
3237 | The client parts of the http and https transport plugins can be configured | ||
3238 | to use a proxy to connect to the hostlist server. This functionality can | ||
3239 | be configured in the configuration file directly or using the | ||
3240 | gnunet-setup tool. | ||
3241 | |||
3242 | Both the HTTP and HTTPS clients support the following proxy types at | ||
3243 | the moment: | ||
3244 | |||
3245 | @itemize @bullet | ||
3246 | @item HTTP 1.1 proxy | ||
3247 | @item SOCKS 4/4a/5/5 with hostname | ||
3248 | @end itemize | ||
3249 | |||
3250 | In addition authentication at the proxy with username and password can be | ||
3251 | configured. | ||
3252 | |||
3253 | To configure proxy support for the clients in the gnunet-setup tool, | ||
3254 | select the "transport" tab and activate the respective plugin. Now you | ||
3255 | can select the appropriate proxy type. The hostname or IP address | ||
3256 | (including port if required) has to be entered in the "Proxy hostname" | ||
3257 | textbox. If required, enter username and password in the "Proxy username" | ||
3258 | and "Proxy password" boxes. Be aware that these information will be stored | ||
3259 | in the configuration in plain text. | ||
3260 | |||
3261 | To configure these options directly in the configuration, you can | ||
3262 | configure the following settings in the @code{[transport-http_client]} | ||
3263 | and @code{[transport-https_client]} section of the configuration: | ||
3264 | |||
3265 | @example | ||
3266 | # Type of proxy server, | ||
3267 | # Valid values: HTTP, SOCKS4, SOCKS5, SOCKS4A, SOCKS5_HOSTNAME | ||
3268 | # Default: HTTP | ||
3269 | # PROXY_TYPE = HTTP | ||
3270 | |||
3271 | # Hostname or IP of proxy server | ||
3272 | # PROXY = | ||
3273 | # User name for proxy server | ||
3274 | # PROXY_USERNAME = | ||
3275 | # User password for proxy server | ||
3276 | # PROXY_PASSWORD = | ||
3277 | @end example | ||
3278 | |||
3279 | @node Configuring the GNU Name System | ||
3280 | @subsection Configuring the GNU Name System | ||
3281 | |||
3282 | @menu | ||
3283 | * Configuring system-wide DNS interception:: | ||
3284 | * Configuring the GNS nsswitch plugin:: | ||
3285 | * Configuring GNS on W32:: | ||
3286 | * GNS Proxy Setup:: | ||
3287 | * Setup of the GNS CA:: | ||
3288 | * Testing the GNS setup:: | ||
3289 | * Automatic Shortening in the GNU Name System:: | ||
3290 | @end menu | ||
3291 | |||
3292 | |||
3293 | @node Configuring system-wide DNS interception | ||
3294 | @subsubsection Configuring system-wide DNS interception | ||
3295 | |||
3296 | Before you install GNUnet, make sure you have a user and group 'gnunet' | ||
3297 | as well as an empty group 'gnunetdns'. | ||
3298 | |||
3299 | When using GNUnet with system-wide DNS interception, it is absolutely | ||
3300 | necessary for all GNUnet service processes to be started by | ||
3301 | @code{gnunet-service-arm} as user and group 'gnunet'. You also need to be | ||
3302 | sure to run @code{make install} as root (or use the @code{sudo} option to | ||
3303 | configure) to grant GNUnet sufficient privileges. | ||
3304 | |||
3305 | With this setup, all that is required for enabling system-wide DNS | ||
3306 | interception is for some GNUnet component (VPN or GNS) to request it. | ||
3307 | The @code{gnunet-service-dns} will then start helper programs that will | ||
3308 | make the necessary changes to your firewall (@code{iptables}) rules. | ||
3309 | |||
3310 | Note that this will NOT work if your system sends out DNS traffic to a | ||
3311 | link-local IPv6 address, as in this case GNUnet can intercept the traffic, | ||
3312 | but not inject the responses from the link-local IPv6 address. Hence you | ||
3313 | cannot use system-wide DNS interception in conjunction with link-local | ||
3314 | IPv6-based DNS servers. If such a DNS server is used, it will bypass | ||
3315 | GNUnet's DNS traffic interception. | ||
3316 | |||
3317 | Using the GNU Name System (GNS) requires two different configuration | ||
3318 | steps. | ||
3319 | First of all, GNS needs to be integrated with the operating system. Most | ||
3320 | of this section is about the operating system level integration. | ||
3321 | |||
3322 | Additionally, each individual user who wants to use the system must also | ||
3323 | initialize their GNS zones. This can be done by running (after starting | ||
3324 | GNUnet) | ||
3325 | |||
3326 | @example | ||
3327 | $ gnunet-gns-import.sh | ||
3328 | @end example | ||
3329 | |||
3330 | @noindent | ||
3331 | after the local GNUnet peer has been started. Note that the namestore (in | ||
3332 | particular the namestore database backend) should not be reconfigured | ||
3333 | afterwards (as records are not automatically migrated between backends). | ||
3334 | |||
3335 | The remainder of this chapter will detail the various methods for | ||
3336 | configuring the use of GNS with your operating system. | ||
3337 | |||
3338 | At this point in time you have different options depending on your OS: | ||
3339 | |||
3340 | @table @asis | ||
3341 | |||
3342 | @item Use the gnunet-gns-proxy This approach works for all operating | ||
3343 | systems and is likely the easiest. However, it enables GNS only for | ||
3344 | browsers, not for other applications that might be using DNS, such as SSH. | ||
3345 | Still, using the proxy is required for using HTTP with GNS and is thus | ||
3346 | recommended for all users. To do this, you simply have to run the | ||
3347 | @code{gnunet-gns-proxy-setup-ca} script as the user who will run the | ||
3348 | browser (this will create a GNS certificate authority (CA) on your system | ||
3349 | and import its key into your browser), then start @code{gnunet-gns-proxy} | ||
3350 | and inform your browser to use the Socks5 proxy which | ||
3351 | @code{gnunet-gns-proxy} makes available by default on port 7777. | ||
3352 | @item Use a nsswitch plugin (recommended on GNU systems) | ||
3353 | This approach has the advantage of offering fully personalized resolution | ||
3354 | even on multi-user systems. A potential disadvantage is that some | ||
3355 | applications might be able to bypass GNS. | ||
3356 | @item Use a W32 resolver plugin (recommended on W32) | ||
3357 | This is currently the only option on W32 systems. | ||
3358 | @item Use system-wide DNS packet interception | ||
3359 | This approach is recommended for the GNUnet VPN. It can be used to handle | ||
3360 | GNS at the same time; however, if you only use this method, you will only | ||
3361 | get one root zone per machine (not so great for multi-user systems). | ||
3362 | @end table | ||
3363 | |||
3364 | You can combine system-wide DNS packet interception with the nsswitch | ||
3365 | plugin. | ||
3366 | The setup of the system-wide DNS interception is described here. All of | ||
3367 | the other GNS-specific configuration steps are described in the following | ||
3368 | sections. | ||
3369 | |||
3370 | @node Configuring the GNS nsswitch plugin | ||
3371 | @subsubsection Configuring the GNS nsswitch plugin | ||
3372 | |||
3373 | The Name Service Switch (NSS) is a facility in Unix-like operating systems | ||
3374 | @footnote{More accurate: NSS is a functionality of the GNU C Library} | ||
3375 | that provides a variety of sources for common configuration databases and | ||
3376 | name resolution mechanisms. | ||
3377 | A superuser (system administrator) usually configures the | ||
3378 | operating system's name services using the file | ||
3379 | @file{/etc/nsswitch.conf}. | ||
3380 | |||
3381 | GNS provides a NSS plugin to integrate GNS name resolution with the | ||
3382 | operating system's name resolution process. | ||
3383 | To use the GNS NSS plugin you have to either | ||
3384 | |||
3385 | @itemize @bullet | ||
3386 | @item install GNUnet as root or | ||
3387 | @item compile GNUnet with the @code{--with-sudo=yes} switch. | ||
3388 | @end itemize | ||
3389 | |||
3390 | Name resolution is controlled by the @emph{hosts} section in the NSS | ||
3391 | configuration. By default this section first performs a lookup in the | ||
3392 | @file{/etc/hosts} file and then in DNS. | ||
3393 | The nsswitch file should contain a line similar to: | ||
3394 | |||
3395 | @example | ||
3396 | hosts: files dns [NOTFOUND=return] mdns4_minimal mdns4 | ||
3397 | @end example | ||
3398 | |||
3399 | @noindent | ||
3400 | Here the GNS NSS plugin can be added to perform a GNS lookup before | ||
3401 | performing a DNS lookup. | ||
3402 | The GNS NSS plugin has to be added to the "hosts" section in | ||
3403 | @file{/etc/nsswitch.conf} file before DNS related plugins: | ||
3404 | |||
3405 | @example | ||
3406 | ... | ||
3407 | hosts: files gns [NOTFOUND=return] dns mdns4_minimal mdns4 | ||
3408 | ... | ||
3409 | @end example | ||
3410 | |||
3411 | @noindent | ||
3412 | The @code{NOTFOUND=return} will ensure that if a @code{.gnu} name is not | ||
3413 | found in GNS it will not be queried in DNS. | ||
3414 | |||
3415 | @node Configuring GNS on W32 | ||
3416 | @subsubsection Configuring GNS on W32 | ||
3417 | |||
3418 | This document is a guide to configuring GNU Name System on W32-compatible | ||
3419 | platforms. | ||
3420 | |||
3421 | After GNUnet is installed, run the w32nsp-install tool: | ||
3422 | |||
3423 | @example | ||
3424 | w32nsp-install.exe libw32nsp-0.dll | ||
3425 | @end example | ||
3426 | |||
3427 | @noindent | ||
3428 | ('0' is the library version of W32 NSP; it might increase in the future, | ||
3429 | change the invocation accordingly). | ||
3430 | |||
3431 | This will install GNS namespace provider into the system and allow other | ||
3432 | applications to resolve names that end in '@strong{gnu}' | ||
3433 | and '@strong{zkey}'. Note that namespace provider requires | ||
3434 | gnunet-gns-helper-service-w32 to be running, as well as gns service | ||
3435 | itself (and its usual dependencies). | ||
3436 | |||
3437 | Namespace provider is hardcoded to connect to @strong{127.0.0.1:5353}, | ||
3438 | and this is where gnunet-gns-helper-service-w32 should be listening to | ||
3439 | (and is configured to listen to by default). | ||
3440 | |||
3441 | To uninstall the provider, run: | ||
3442 | |||
3443 | @example | ||
3444 | w32nsp-uninstall.exe | ||
3445 | @end example | ||
3446 | |||
3447 | @noindent | ||
3448 | (uses provider GUID to uninstall it, does not need a dll name). | ||
3449 | |||
3450 | Note that while MSDN claims that other applications will only be able to | ||
3451 | use the new namespace provider after re-starting, in reality they might | ||
3452 | stat to use it without that. Conversely, they might stop using the | ||
3453 | provider after it's been uninstalled, even if they were not re-started. | ||
3454 | W32 will not permit namespace provider library to be deleted or | ||
3455 | overwritten while the provider is installed, and while there is at least | ||
3456 | one process still using it (even after it was uninstalled). | ||
3457 | |||
3458 | @node GNS Proxy Setup | ||
3459 | @subsubsection GNS Proxy Setup | ||
3460 | |||
3461 | When using the GNU Name System (GNS) to browse the WWW, there are several | ||
3462 | issues that can be solved by adding the GNS Proxy to your setup: | ||
3463 | |||
3464 | @itemize @bullet | ||
3465 | |||
3466 | @item If the target website does not support GNS, it might assume that it | ||
3467 | is operating under some name in the legacy DNS system (such as | ||
3468 | example.com). It may then attempt to set cookies for that domain, and the | ||
3469 | web server might expect a @code{Host: example.com} header in the request | ||
3470 | from your browser. | ||
3471 | However, your browser might be using @code{example.gnu} for the | ||
3472 | @code{Host} header and might only accept (and send) cookies for | ||
3473 | @code{example.gnu}. The GNS Proxy will perform the necessary translations | ||
3474 | of the hostnames for cookies and HTTP headers (using the LEHO record for | ||
3475 | the target domain as the desired substitute). | ||
3476 | |||
3477 | @item If using HTTPS, the target site might include an SSL certificate | ||
3478 | which is either only valid for the LEHO domain or might match a TLSA | ||
3479 | record in GNS. However, your browser would expect a valid certificate for | ||
3480 | @code{example.gnu}, not for some legacy domain name. The proxy will | ||
3481 | validate the certificate (either against LEHO or TLSA) and then | ||
3482 | on-the-fly produce a valid certificate for the exchange, signed by your | ||
3483 | own CA. Assuming you installed the CA of your proxy in your browser's | ||
3484 | certificate authority list, your browser will then trust the | ||
3485 | HTTPS/SSL/TLS connection, as the hostname mismatch is hidden by the proxy. | ||
3486 | |||
3487 | @item Finally, the proxy will in the future indicate to the server that it | ||
3488 | speaks GNS, which will enable server operators to deliver GNS-enabled web | ||
3489 | sites to your browser (and continue to deliver legacy links to legacy | ||
3490 | browsers) | ||
3491 | @end itemize | ||
3492 | |||
3493 | @node Setup of the GNS CA | ||
3494 | @subsubsection Setup of the GNS CA | ||
3495 | |||
3496 | First you need to create a CA certificate that the proxy can use. | ||
3497 | To do so use the provided script gnunet-gns-proxy-ca: | ||
3498 | |||
3499 | @example | ||
3500 | $ gnunet-gns-proxy-setup-ca | ||
3501 | @end example | ||
3502 | |||
3503 | @noindent | ||
3504 | This will create a personal certification authority for you and add this | ||
3505 | authority to the firefox and chrome database. The proxy will use the this | ||
3506 | CA certificate to generate @code{*.gnu} client certificates on the fly. | ||
3507 | |||
3508 | Note that the proxy uses libcurl. Make sure your version of libcurl uses | ||
3509 | GnuTLS and NOT OpenSSL. The proxy will @b{not} work with libcurl compiled | ||
3510 | against OpenSSL. | ||
3511 | |||
3512 | You can check the configuration your libcurl was build with by | ||
3513 | running: | ||
3514 | |||
3515 | @example | ||
3516 | curl --version | ||
3517 | @end example | ||
3518 | |||
3519 | the output will look like this (without the linebreaks): | ||
3520 | |||
3521 | @example | ||
3522 | gnurl --version | ||
3523 | curl 7.56.0 (x86_64-unknown-linux-gnu) libcurl/7.56.0 \ | ||
3524 | GnuTLS/3.5.13 zlib/1.2.11 libidn2/2.0.4 | ||
3525 | Release-Date: 2017-10-08 | ||
3526 | Protocols: http https | ||
3527 | Features: AsynchDNS IDN IPv6 Largefile NTLM SSL libz \ | ||
3528 | TLS-SRP UnixSockets HTTPS-proxy | ||
3529 | @end example | ||
3530 | |||
3531 | @node Testing the GNS setup | ||
3532 | @subsubsection Testing the GNS setup | ||
3533 | |||
3534 | Now for testing purposes we can create some records in our zone to test | ||
3535 | the SSL functionality of the proxy: | ||
3536 | |||
3537 | @example | ||
3538 | $ gnunet-namestore -a -e "1 d" -n "homepage" -t A -V 131.159.74.67 | ||
3539 | $ gnunet-namestore -a -e "1 d" -n "homepage" -t LEHO -V "gnunet.org" | ||
3540 | @end example | ||
3541 | |||
3542 | @noindent | ||
3543 | At this point we can start the proxy. Simply execute | ||
3544 | |||
3545 | @example | ||
3546 | $ gnunet-gns-proxy | ||
3547 | @end example | ||
3548 | |||
3549 | @noindent | ||
3550 | Configure your browser to use this SOCKSv5 proxy on port 7777 and visit | ||
3551 | this link. | ||
3552 | If you use @command{Firefox} (or one of its deriviates/forks such as | ||
3553 | Icecat) you also have to go to @code{about:config} and set the key | ||
3554 | @code{network.proxy.socks_remote_dns} to @code{true}. | ||
3555 | |||
3556 | When you visit @code{https://homepage.gnu/}, you should get to the | ||
3557 | @code{https://gnunet.org/} frontpage and the browser (with the correctly | ||
3558 | configured proxy) should give you a valid SSL certificate for | ||
3559 | @code{homepage.gnu} and no warnings. It should look like this: | ||
3560 | |||
3561 | @c FIXME: Image does not exist, create it or save it from Drupal? | ||
3562 | @c @image{images/gnunethpgns.png,5in,, picture of homepage.gnu in Webbrowser} | ||
3563 | |||
3564 | @node Automatic Shortening in the GNU Name System | ||
3565 | @subsubsection Automatic Shortening in the GNU Name System | ||
3566 | |||
3567 | This page describes a possible option for 'automatic name shortening', | ||
3568 | which you can choose to enable with the GNU Name System. | ||
3569 | |||
3570 | When GNS encounters a name for the first time, it can use the 'NICK' | ||
3571 | record of the originating zone to automatically generate a name for the | ||
3572 | zone. If automatic shortening is enabled, those auto-generated names will | ||
3573 | be placed (as private records) into your personal 'shorten' zone (to | ||
3574 | prevent confusion with manually selected names). | ||
3575 | Then, in the future, if the same name is encountered again, GNS will | ||
3576 | display the shortened name instead (the first time, the long name will | ||
3577 | still be used as shortening typically happens asynchronously as looking up | ||
3578 | the 'NICK' record takes some time). Using this feature can be a convenient | ||
3579 | way to avoid very long @code{.gnu} names; however, note that names from | ||
3580 | the shorten-zone are assigned on a first-come-first-serve basis and should | ||
3581 | not be trusted. Furthermore, if you enable this feature, you will no | ||
3582 | longer see the full delegation chain for zones once shortening has been | ||
3583 | applied. | ||
3584 | |||
3585 | @node Configuring the GNUnet VPN | ||
3586 | @subsection Configuring the GNUnet VPN | ||
3587 | |||
3588 | @menu | ||
3589 | * IPv4 address for interface:: | ||
3590 | * IPv6 address for interface:: | ||
3591 | * Configuring the GNUnet VPN DNS:: | ||
3592 | * Configuring the GNUnet VPN Exit Service:: | ||
3593 | * IP Address of external DNS resolver:: | ||
3594 | * IPv4 address for Exit interface:: | ||
3595 | * IPv6 address for Exit interface:: | ||
3596 | @end menu | ||
3597 | |||
3598 | Before configuring the GNUnet VPN, please make sure that system-wide DNS | ||
3599 | interception is configured properly as described in the section on the | ||
3600 | GNUnet DNS setup. @pxref{Configuring the GNU Name System}, | ||
3601 | if you haven't done so already. | ||
3602 | |||
3603 | The default options for the GNUnet VPN are usually sufficient to use | ||
3604 | GNUnet as a Layer 2 for your Internet connection. | ||
3605 | However, what you always have to specify is which IP protocol you want | ||
3606 | to tunnel: IPv4, IPv6 or both. | ||
3607 | Furthermore, if you tunnel both, you most likely should also tunnel | ||
3608 | all of your DNS requests. | ||
3609 | You theoretically can tunnel "only" your DNS traffic, but that usually | ||
3610 | makes little sense. | ||
3611 | |||
3612 | The other options as shown on the gnunet-setup tool are: | ||
3613 | |||
3614 | @node IPv4 address for interface | ||
3615 | @subsubsection IPv4 address for interface | ||
3616 | |||
3617 | This is the IPv4 address the VPN interface will get. You should pick an | ||
3618 | 'private' IPv4 network that is not yet in use for you system. For example, | ||
3619 | if you use @code{10.0.0.1/255.255.0.0} already, you might use | ||
3620 | @code{10.1.0.1/255.255.0.0}. | ||
3621 | If you use @code{10.0.0.1/255.0.0.0} already, then you might use | ||
3622 | @code{192.168.0.1/255.255.0.0}. | ||
3623 | If your system is not in a private IP-network, using any of the above will | ||
3624 | work fine. | ||
3625 | You should try to make the mask of the address big enough | ||
3626 | (@code{255.255.0.0} or, even better, @code{255.0.0.0}) to allow more | ||
3627 | mappings of remote IP Addresses into this range. | ||
3628 | However, even a @code{255.255.255.0} mask will suffice for most users. | ||
3629 | |||
3630 | @node IPv6 address for interface | ||
3631 | @subsubsection IPv6 address for interface | ||
3632 | |||
3633 | The IPv6 address the VPN interface will get. Here you can specify any | ||
3634 | non-link-local address (the address should not begin with @code{fe80:}). | ||
3635 | A subnet Unique Local Unicast (@code{fd00::/8} prefix) that you are | ||
3636 | currently not using would be a good choice. | ||
3637 | |||
3638 | @node Configuring the GNUnet VPN DNS | ||
3639 | @subsubsection Configuring the GNUnet VPN DNS | ||
3640 | |||
3641 | To resolve names for remote nodes, activate the DNS exit option. | ||
3642 | |||
3643 | @node Configuring the GNUnet VPN Exit Service | ||
3644 | @subsubsection Configuring the GNUnet VPN Exit Service | ||
3645 | |||
3646 | If you want to allow other users to share your Internet connection (yes, | ||
3647 | this may be dangerous, just as running a Tor exit node) or want to | ||
3648 | provide access to services on your host (this should be less dangerous, | ||
3649 | as long as those services are secure), you have to enable the GNUnet exit | ||
3650 | daemon. | ||
3651 | |||
3652 | You then get to specify which exit functions you want to provide. By | ||
3653 | enabling the exit daemon, you will always automatically provide exit | ||
3654 | functions for manually configured local services (this component of the | ||
3655 | system is under | ||
3656 | development and not documented further at this time). As for those | ||
3657 | services you explicitly specify the target IP address and port, there is | ||
3658 | no significant security risk in doing so. | ||
3659 | |||
3660 | Furthermore, you can serve as a DNS, IPv4 or IPv6 exit to the Internet. | ||
3661 | Being a DNS exit is usually pretty harmless. However, enabling IPv4 or | ||
3662 | IPv6-exit without further precautions may enable adversaries to access | ||
3663 | your local network, send spam, attack other systems from your Internet | ||
3664 | connection and to other mischief that will appear to come from your | ||
3665 | machine. This may or may not get you into legal trouble. | ||
3666 | If you want to allow IPv4 or IPv6-exit functionality, you should strongly | ||
3667 | consider adding additional firewall rules manually to protect your local | ||
3668 | network and to restrict outgoing TCP traffic (i.e. by not allowing access | ||
3669 | to port 25). While we plan to improve exit-filtering in the future, | ||
3670 | you're currently on your own here. | ||
3671 | Essentially, be prepared for any kind of IP-traffic to exit the respective | ||
3672 | TUN interface (and GNUnet will enable IP-forwarding and NAT for the | ||
3673 | interface automatically). | ||
3674 | |||
3675 | Additional configuration options of the exit as shown by the gnunet-setup | ||
3676 | tool are: | ||
3677 | |||
3678 | @node IP Address of external DNS resolver | ||
3679 | @subsubsection IP Address of external DNS resolver | ||
3680 | |||
3681 | If DNS traffic is to exit your machine, it will be send to this DNS | ||
3682 | resolver. You can specify an IPv4 or IPv6 address. | ||
3683 | |||
3684 | @node IPv4 address for Exit interface | ||
3685 | @subsubsection IPv4 address for Exit interface | ||
3686 | |||
3687 | This is the IPv4 address the Interface will get. Make the mask of the | ||
3688 | address big enough (255.255.0.0 or, even better, 255.0.0.0) to allow more | ||
3689 | mappings of IP addresses into this range. As for the VPN interface, any | ||
3690 | unused, private IPv4 address range will do. | ||
3691 | |||
3692 | @node IPv6 address for Exit interface | ||
3693 | @subsubsection IPv6 address for Exit interface | ||
3694 | |||
3695 | The public IPv6 address the interface will get. If your kernel is not a | ||
3696 | very recent kernel and you are willing to manually enable IPv6-NAT, the | ||
3697 | IPv6 address you specify here must be a globally routed IPv6 address of | ||
3698 | your host. | ||
3699 | |||
3700 | Suppose your host has the address @code{2001:4ca0::1234/64}, then | ||
3701 | using @code{2001:4ca0::1:0/112} would be fine (keep the first 64 bits, | ||
3702 | then change at least one bit in the range before the bitmask, in the | ||
3703 | example above we changed bit 111 from 0 to 1). | ||
3704 | |||
3705 | You may also have to configure your router to route traffic for the entire | ||
3706 | subnet (@code{2001:4ca0::1:0/112} for example) through your computer (this | ||
3707 | should be automatic with IPv6, but obviously anything can be | ||
3708 | disabled). | ||
3709 | |||
3710 | @node Bandwidth Configuration | ||
3711 | @subsection Bandwidth Configuration | ||
3712 | |||
3713 | You can specify how many bandwidth GNUnet is allowed to use to receive | ||
3714 | and send data. This is important for users with limited bandwidth or | ||
3715 | traffic volume. | ||
3716 | |||
3717 | @node Configuring NAT | ||
3718 | @subsection Configuring NAT | ||
3719 | |||
3720 | Most hosts today do not have a normal global IP address but instead are | ||
3721 | behind a router performing Network Address Translation (NAT) which assigns | ||
3722 | each host in the local network a private IP address. | ||
3723 | As a result, these machines cannot trivially receive inbound connections | ||
3724 | from the Internet. GNUnet supports NAT traversal to enable these machines | ||
3725 | to receive incoming connections from other peers despite their | ||
3726 | limitations. | ||
3727 | |||
3728 | In an ideal world, you can press the "Attempt automatic configuration" | ||
3729 | button in gnunet-setup to automatically configure your peer correctly. | ||
3730 | Alternatively, your distribution might have already triggered this | ||
3731 | automatic configuration during the installation process. | ||
3732 | However, automatic configuration can fail to determine the optimal | ||
3733 | settings, resulting in your peer either not receiving as many connections | ||
3734 | as possible, or in the worst case it not connecting to the network at all. | ||
3735 | |||
3736 | To manually configure the peer, you need to know a few things about your | ||
3737 | network setup. First, determine if you are behind a NAT in the first | ||
3738 | place. | ||
3739 | This is always the case if your IP address starts with "10.*" or | ||
3740 | "192.168.*". Next, if you have control over your NAT router, you may | ||
3741 | choose to manually configure it to allow GNUnet traffic to your host. | ||
3742 | If you have configured your NAT to forward traffic on ports 2086 (and | ||
3743 | possibly 1080) to your host, you can check the "NAT ports have been opened | ||
3744 | manually" option, which corresponds to the "PUNCHED_NAT" option in the | ||
3745 | configuration file. If you did not punch your NAT box, it may still be | ||
3746 | configured to support UPnP, which allows GNUnet to automatically | ||
3747 | configure it. In that case, you need to install the "upnpc" command, | ||
3748 | enable UPnP (or PMP) on your NAT box and set the "Enable NAT traversal | ||
3749 | via UPnP or PMP" option (corresponding to "ENABLE_UPNP" in the | ||
3750 | configuration file). | ||
3751 | |||
3752 | Some NAT boxes can be traversed using the autonomous NAT traversal method. | ||
3753 | This requires certain GNUnet components to be installed with "SUID" | ||
3754 | prividledges on your system (so if you're installing on a system you do | ||
3755 | not have administrative rights to, this will not work). | ||
3756 | If you installed as 'root', you can enable autonomous NAT traversal by | ||
3757 | checking the "Enable NAT traversal using ICMP method". | ||
3758 | The ICMP method requires a way to determine your NAT's external (global) | ||
3759 | IP address. This can be done using either UPnP, DynDNS, or by manual | ||
3760 | configuration. If you have a DynDNS name or know your external IP address, | ||
3761 | you should enter that name under "External (public) IPv4 address" (which | ||
3762 | corresponds to the "EXTERNAL_ADDRESS" option in the configuration file). | ||
3763 | If you leave the option empty, GNUnet will try to determine your external | ||
3764 | IP address automatically (which may fail, in which case autonomous | ||
3765 | NAT traversal will then not work). | ||
3766 | |||
3767 | Finally, if you yourself are not behind NAT but want to be able to | ||
3768 | connect to NATed peers using autonomous NAT traversal, you need to check | ||
3769 | the "Enable connecting to NATed peers using ICMP method" box. | ||
3770 | |||
3771 | |||
3772 | @node Peer configuration for distributions | ||
3773 | @subsection Peer configuration for distributions | ||
3774 | |||
3775 | The "GNUNET_DATA_HOME" in "[path]" in @file{/etc/gnunet.conf} should be | ||
3776 | manually set to "/var/lib/gnunet/data/" as the default | ||
3777 | "~/.local/share/gnunet/" is probably not that appropriate in this case. | ||
3778 | Similarly, distributions may consider pointing "GNUNET_RUNTIME_DIR" to | ||
3779 | "/var/run/gnunet/" and "GNUNET_HOME" to "/var/lib/gnunet/". Also, should a | ||
3780 | distribution decide to override system defaults, all of these changes | ||
3781 | should be done in a custom @file{/etc/gnunet.conf} and not in the files | ||
3782 | in the @file{config.d/} directory. | ||
3783 | |||
3784 | Given the proposed access permissions, the "gnunet-setup" tool must be | ||
3785 | run as use "gnunet" (and with option "-c /etc/gnunet.conf" so that it | ||
3786 | modifies the system configuration). As always, gnunet-setup should be run | ||
3787 | after the GNUnet peer was stopped using "gnunet-arm -e". Distributions | ||
3788 | might want to include a wrapper for gnunet-setup that allows the | ||
3789 | desktop-user to "sudo" (i.e. using gtksudo) to the "gnunet" user account | ||
3790 | and then runs "gnunet-arm -e", "gnunet-setup" and "gnunet-arm -s" in | ||
3791 | sequence. | ||
3792 | |||
3793 | @node How to start and stop a GNUnet peer | ||
3794 | @section How to start and stop a GNUnet peer | ||
3795 | |||
3796 | This section describes how to start a GNUnet peer. It assumes that you | ||
3797 | have already compiled and installed GNUnet and its' dependencies. | ||
3798 | Before you start a GNUnet peer, you may want to create a configuration | ||
3799 | file using gnunet-setup (but you do not have to). | ||
3800 | Sane defaults should exist in your | ||
3801 | @file{$GNUNET_PREFIX/share/gnunet/config.d/} directory, so in practice | ||
3802 | you could simply start without any configuration. If you want to | ||
3803 | configure your peer later, you need to stop it before invoking the | ||
3804 | @code{gnunet-setup} tool to customize further and to test your | ||
3805 | configuration (@code{gnunet-setup} has build-in test functions). | ||
3806 | |||
3807 | The most important option you might have to still set by hand is in | ||
3808 | [PATHS]. Here, you use the option "GNUNET_HOME" to specify the path where | ||
3809 | GNUnet should store its data. | ||
3810 | It defaults to @code{$HOME/}, which again should work for most users. | ||
3811 | Make sure that the directory specified as GNUNET_HOME is writable to | ||
3812 | the user that you will use to run GNUnet (note that you can run frontends | ||
3813 | using other users, GNUNET_HOME must only be accessible to the user used to | ||
3814 | run the background processes). | ||
3815 | |||
3816 | You will also need to make one central decision: should all of GNUnet be | ||
3817 | run under your normal UID, or do you want distinguish between system-wide | ||
3818 | (user-independent) GNUnet services and personal GNUnet services. The | ||
3819 | multi-user setup is slightly more complicated, but also more secure and | ||
3820 | generally recommended. | ||
3821 | |||
3822 | @menu | ||
3823 | * The Single-User Setup:: | ||
3824 | * The Multi-User Setup:: | ||
3825 | * Killing GNUnet services:: | ||
3826 | * Access Control for GNUnet:: | ||
3827 | @end menu | ||
3828 | |||
3829 | @node The Single-User Setup | ||
3830 | @subsection The Single-User Setup | ||
3831 | |||
3832 | For the single-user setup, you do not need to do anything special and can | ||
3833 | just start the GNUnet background processes using @code{gnunet-arm}. | ||
3834 | By default, GNUnet looks in @file{~/.config/gnunet.conf} for a | ||
3835 | configuration (or @code{$XDG_CONFIG_HOME/gnunet.conf} if@ | ||
3836 | @code{$XDG_CONFIG_HOME} is defined). If your configuration lives | ||
3837 | elsewhere, you need to pass the @code{-c FILENAME} option to all GNUnet | ||
3838 | commands. | ||
3839 | |||
3840 | Assuming the configuration file is called @file{~/.config/gnunet.conf}, | ||
3841 | you start your peer using the @code{gnunet-arm} command (say as user | ||
3842 | @code{gnunet}) using: | ||
3843 | |||
3844 | @example | ||
3845 | gnunet-arm -c ~/.config/gnunet.conf -s | ||
3846 | @end example | ||
3847 | |||
3848 | @noindent | ||
3849 | The "-s" option here is for "start". The command should return almost | ||
3850 | instantly. If you want to stop GNUnet, you can use: | ||
3851 | |||
3852 | @example | ||
3853 | gnunet-arm -c ~/.config/gnunet.conf -e | ||
3854 | @end example | ||
3855 | |||
3856 | @noindent | ||
3857 | The "-e" option here is for "end". | ||
3858 | |||
3859 | Note that this will only start the basic peer, no actual applications | ||
3860 | will be available. | ||
3861 | If you want to start the file-sharing service, use (after starting | ||
3862 | GNUnet): | ||
3863 | |||
3864 | @example | ||
3865 | gnunet-arm -c ~/.config/gnunet.conf -i fs | ||
3866 | @end example | ||
3867 | |||
3868 | @noindent | ||
3869 | The "-i fs" option here is for "initialize" the "fs" (file-sharing) | ||
3870 | application. You can also selectively kill only file-sharing support using | ||
3871 | |||
3872 | @example | ||
3873 | gnunet-arm -c ~/.config/gnunet.conf -k fs | ||
3874 | @end example | ||
3875 | |||
3876 | @noindent | ||
3877 | Assuming that you want certain services (like file-sharing) to be always | ||
3878 | automatically started whenever you start GNUnet, you can activate them by | ||
3879 | setting "FORCESTART=YES" in the respective section of the configuration | ||
3880 | file (for example, "[fs]"). Then GNUnet with file-sharing support would | ||
3881 | be started whenever you@ enter: | ||
3882 | |||
3883 | @example | ||
3884 | gnunet-arm -c ~/.config/gnunet.conf -s | ||
3885 | @end example | ||
3886 | |||
3887 | @noindent | ||
3888 | Alternatively, you can combine the two options: | ||
3889 | |||
3890 | @example | ||
3891 | gnunet-arm -c ~/.config/gnunet.conf -s -i fs | ||
3892 | @end example | ||
3893 | |||
3894 | @noindent | ||
3895 | Using @code{gnunet-arm} is also the preferred method for initializing | ||
3896 | GNUnet from @code{init}. | ||
3897 | |||
3898 | Finally, you should edit your @code{crontab} (using the @code{crontab} | ||
3899 | command) and insert a line@ | ||
3900 | |||
3901 | @example | ||
3902 | @@reboot gnunet-arm -c ~/.config/gnunet.conf -s | ||
3903 | @end example | ||
3904 | |||
3905 | to automatically start your peer whenever your system boots. | ||
3906 | |||
3907 | @node The Multi-User Setup | ||
3908 | @subsection The Multi-User Setup | ||
3909 | |||
3910 | This requires you to create a user @code{gnunet} and an additional group | ||
3911 | @code{gnunetdns}, prior to running @code{make install} during | ||
3912 | installation. | ||
3913 | Then, you create a configuration file @file{/etc/gnunet.conf} which should | ||
3914 | contain the lines:@ | ||
3915 | |||
3916 | @example | ||
3917 | [arm] | ||
3918 | SYSTEM_ONLY = YES | ||
3919 | USER_ONLY = NO | ||
3920 | @end example | ||
3921 | |||
3922 | @noindent | ||
3923 | Then, perform the same steps to run GNUnet as in the per-user | ||
3924 | configuration, except as user @code{gnunet} (including the | ||
3925 | @code{crontab} installation). | ||
3926 | You may also want to run @code{gnunet-setup} to configure your peer | ||
3927 | (databases, etc.). | ||
3928 | Make sure to pass @code{-c /etc/gnunet.conf} to all commands. If you | ||
3929 | run @code{gnunet-setup} as user @code{gnunet}, you might need to change | ||
3930 | permissions on @file{/etc/gnunet.conf} so that the @code{gnunet} user can | ||
3931 | write to the file (during setup). | ||
3932 | |||
3933 | Afterwards, you need to perform another setup step for each normal user | ||
3934 | account from which you want to access GNUnet. First, grant the normal user | ||
3935 | (@code{$USER}) permission to the group gnunet: | ||
3936 | |||
3937 | @example | ||
3938 | # adduser $USER gnunet | ||
3939 | @end example | ||
3940 | |||
3941 | @noindent | ||
3942 | Then, create a configuration file in @file{~/.config/gnunet.conf} for the | ||
3943 | $USER with the lines: | ||
3944 | |||
3945 | @example | ||
3946 | [arm] | ||
3947 | SYSTEM_ONLY = NO | ||
3948 | USER_ONLY = YES | ||
3949 | @end example | ||
3950 | |||
3951 | @noindent | ||
3952 | This will ensure that @code{gnunet-arm} when started by the normal user | ||
3953 | will only run services that are per-user, and otherwise rely on the | ||
3954 | system-wide services. | ||
3955 | Note that the normal user may run gnunet-setup, but the | ||
3956 | configuration would be ineffective as the system-wide services will use | ||
3957 | @file{/etc/gnunet.conf} and ignore options set by individual users. | ||
3958 | |||
3959 | Again, each user should then start the peer using | ||
3960 | @file{gnunet-arm -s} --- and strongly consider adding logic to start | ||
3961 | the peer automatically to their crontab. | ||
3962 | |||
3963 | Afterwards, you should see two (or more, if you have more than one USER) | ||
3964 | @code{gnunet-service-arm} processes running in your system. | ||
3965 | |||
3966 | @node Killing GNUnet services | ||
3967 | @subsection Killing GNUnet services | ||
3968 | |||
3969 | It is not necessary to stop GNUnet services explicitly when shutting | ||
3970 | down your computer. | ||
3971 | |||
3972 | It should be noted that manually killing "most" of the | ||
3973 | @code{gnunet-service} processes is generally not a successful method for | ||
3974 | stopping a peer (since @code{gnunet-service-arm} will instantly restart | ||
3975 | them). The best way to explicitly stop a peer is using | ||
3976 | @code{gnunet-arm -e}; note that the per-user services may need to be | ||
3977 | terminated before the system-wide services will terminate normally. | ||
3978 | |||
3979 | @node Access Control for GNUnet | ||
3980 | @subsection Access Control for GNUnet | ||
3981 | |||
3982 | This chapter documents how we plan to make access control work within the | ||
3983 | GNUnet system for a typical peer. It should be read as a best-practice | ||
3984 | installation guide for advanced users and builders of binary | ||
3985 | distributions. The recommendations in this guide apply to POSIX-systems | ||
3986 | with full support for UNIX domain sockets only. | ||
3987 | |||
3988 | Note that this is an advanced topic. The discussion presumes a very good | ||
3989 | understanding of users, groups and file permissions. Normal users on | ||
3990 | hosts with just a single user can just install GNUnet under their own | ||
3991 | account (and possibly allow the installer to use SUDO to grant additional | ||
3992 | permissions for special GNUnet tools that need additional rights). | ||
3993 | The discussion below largely applies to installations where multiple users | ||
3994 | share a system and to installations where the best possible security is | ||
3995 | paramount. | ||
3996 | |||
3997 | A typical GNUnet system consists of components that fall into four | ||
3998 | categories: | ||
3999 | |||
4000 | @table @asis | ||
4001 | |||
4002 | @item User interfaces | ||
4003 | User interfaces are not security sensitive and are supposed to be run and | ||
4004 | used by normal system users. | ||
4005 | The GTK GUIs and most command-line programs fall into this category. | ||
4006 | Some command-line tools (like gnunet-transport) should be excluded as they | ||
4007 | offer low-level access that normal users should not need. | ||
4008 | @item System services and support tools | ||
4009 | System services should always run and offer services that can then be | ||
4010 | accessed by the normal users. | ||
4011 | System services do not require special permissions, but as they are not | ||
4012 | specific to a particular user, they probably should not run as a | ||
4013 | particular user. Also, there should typically only be one GNUnet peer per | ||
4014 | host. System services include the gnunet-service and gnunet-daemon | ||
4015 | programs; support tools include command-line programs such as gnunet-arm. | ||
4016 | @item Priviledged helpers | ||
4017 | Some GNUnet components require root rights to open raw sockets or perform | ||
4018 | other special operations. These gnunet-helper binaries are typically | ||
4019 | installed SUID and run from services or daemons. | ||
4020 | @item Critical services | ||
4021 | Some GNUnet services (such as the DNS service) can manipulate the service | ||
4022 | in deep and possibly highly security sensitive ways. For example, the DNS | ||
4023 | service can be used to intercept and alter any DNS query originating from | ||
4024 | the local machine. Access to the APIs of these critical services and their | ||
4025 | priviledged helpers must be tightly controlled. | ||
4026 | @end table | ||
4027 | |||
4028 | @c FIXME: The titles of these chapters are too long in the index. | ||
4029 | |||
4030 | @menu | ||
4031 | * Recommendation - Disable access to services via TCP:: | ||
4032 | * Recommendation - Run most services as system user "gnunet":: | ||
4033 | * Recommendation - Control access to services using group "gnunet":: | ||
4034 | * Recommendation - Limit access to certain SUID binaries by group "gnunet":: | ||
4035 | * Recommendation - Limit access to critical gnunet-helper-dns to group "gnunetdns":: | ||
4036 | * Differences between "make install" and these recommendations:: | ||
4037 | @end menu | ||
4038 | |||
4039 | @node Recommendation - Disable access to services via TCP | ||
4040 | @subsubsection Recommendation - Disable access to services via TCP | ||
4041 | |||
4042 | GNUnet services allow two types of access: via TCP socket or via UNIX | ||
4043 | domain socket. | ||
4044 | If the service is available via TCP, access control can only be | ||
4045 | implemented by restricting connections to a particular range of IP | ||
4046 | addresses. | ||
4047 | This is acceptable for non-critical services that are supposed to be | ||
4048 | available to all users on the local system or local network. | ||
4049 | However, as TCP is generally less efficient and it is rarely the case | ||
4050 | that a single GNUnet peer is supposed to serve an entire local network, | ||
4051 | the default configuration should disable TCP access to all GNUnet | ||
4052 | services on systems with support for UNIX domain sockets. | ||
4053 | As of GNUnet 0.9.2, configuration files with TCP access disabled should be | ||
4054 | generated by default. Users can re-enable TCP access to particular | ||
4055 | services simply by specifying a non-zero port number in the section of | ||
4056 | the respective service. | ||
4057 | |||
4058 | |||
4059 | @node Recommendation - Run most services as system user "gnunet" | ||
4060 | @subsubsection Recommendation - Run most services as system user "gnunet" | ||
4061 | |||
4062 | GNUnet's main services should be run as a separate user "gnunet" in a | ||
4063 | special group "gnunet". | ||
4064 | The user "gnunet" should start the peer using "gnunet-arm -s" during | ||
4065 | system startup. The home directory for this user should be | ||
4066 | @file{/var/lib/gnunet} and the configuration file should be | ||
4067 | @file{/etc/gnunet.conf}. | ||
4068 | Only the @code{gnunet} user should have the right to access | ||
4069 | @file{/var/lib/gnunet} (@emph{mode: 700}). | ||
4070 | |||
4071 | @node Recommendation - Control access to services using group "gnunet" | ||
4072 | @subsubsection Recommendation - Control access to services using group "gnunet" | ||
4073 | |||
4074 | Users that should be allowed to use the GNUnet peer should be added to the | ||
4075 | group "gnunet". Using GNUnet's access control mechanism for UNIX domain | ||
4076 | sockets, those services that are considered useful to ordinary users | ||
4077 | should be made available by setting "UNIX_MATCH_GID=YES" for those | ||
4078 | services. | ||
4079 | Again, as shipped, GNUnet provides reasonable defaults. | ||
4080 | Permissions to access the transport and core subsystems might additionally | ||
4081 | be granted without necessarily causing security concerns. | ||
4082 | Some services, such as DNS, must NOT be made accessible to the "gnunet" | ||
4083 | group (and should thus only be accessible to the "gnunet" user and | ||
4084 | services running with this UID). | ||
4085 | |||
4086 | @node Recommendation - Limit access to certain SUID binaries by group "gnunet" | ||
4087 | @subsubsection Recommendation - Limit access to certain SUID binaries by group "gnunet" | ||
4088 | |||
4089 | Most of GNUnet's SUID binaries should be safe even if executed by normal | ||
4090 | users. However, it is possible to reduce the risk a little bit more by | ||
4091 | making these binaries owned by the group "gnunet" and restricting their | ||
4092 | execution to user of the group "gnunet" as well (4750). | ||
4093 | |||
4094 | @node Recommendation - Limit access to critical gnunet-helper-dns to group "gnunetdns" | ||
4095 | @subsubsection Recommendation - Limit access to critical gnunet-helper-dns to group "gnunetdns" | ||
4096 | |||
4097 | A special group "gnunetdns" should be created for controlling access to | ||
4098 | the "gnunet-helper-dns". | ||
4099 | The binary should then be owned by root and be in group "gnunetdns" and | ||
4100 | be installed SUID and only be group-executable (2750). | ||
4101 | @b{Note that the group "gnunetdns" should have no users in it at all, | ||
4102 | ever.} | ||
4103 | The "gnunet-service-dns" program should be executed by user "gnunet" (via | ||
4104 | gnunet-service-arm) with the binary owned by the user "root" and the group | ||
4105 | "gnunetdns" and be SGID (2700). This way, @strong{only} | ||
4106 | "gnunet-service-dns" can change its group to "gnunetdns" and execute the | ||
4107 | helper, and the helper can then run as root (as per SUID). | ||
4108 | Access to the API offered by "gnunet-service-dns" is in turn restricted | ||
4109 | to the user "gnunet" (not the group!), which means that only | ||
4110 | "benign" services can manipulate DNS queries using "gnunet-service-dns". | ||
4111 | |||
4112 | @node Differences between "make install" and these recommendations | ||
4113 | @subsubsection Differences between "make install" and these recommendations | ||
4114 | |||
4115 | The current build system does not set all permissions automatically based | ||
4116 | on the recommendations above. In particular, it does not use the group | ||
4117 | "gnunet" at all (so setting gnunet-helpers other than the | ||
4118 | gnunet-helper-dns to be owned by group "gnunet" must be done manually). | ||
4119 | Furthermore, 'make install' will silently fail to set the DNS binaries to | ||
4120 | be owned by group "gnunetdns" unless that group already exists (!). | ||
4121 | An alternative name for the "gnunetdns" group can be specified using the | ||
4122 | @code{--with-gnunetdns=GRPNAME} configure option. | ||
4123 | |||
diff --git a/doc/documentation/chapters/philosophy.texi b/doc/documentation/chapters/philosophy.texi new file mode 100644 index 000000000..e77415bd8 --- /dev/null +++ b/doc/documentation/chapters/philosophy.texi | |||
@@ -0,0 +1,427 @@ | |||
1 | @cindex Philosophy | ||
2 | @node Philosophy | ||
3 | @chapter Philosophy | ||
4 | |||
5 | @c NOTE: We should probably re-use some of the images lynX created | ||
6 | @c for secushare, showing some of the relations and functionalities | ||
7 | @c of GNUnet. | ||
8 | The foremost goal of the GNUnet project is to become a widely used, | ||
9 | reliable, open, non-discriminating, egalitarian, unconstrained and | ||
10 | censorship-resistant system of free information exchange. | ||
11 | We value free speech above state secrets, law-enforcement or | ||
12 | intellectual property. | ||
13 | GNUnet is supposed to be an anarchistic network, where the only | ||
14 | limitation for participants (devices or people making use of the | ||
15 | network, in the following sometimes called peers) is | ||
16 | that they must contribute enough back to the network such that | ||
17 | their resource consumption does not have a significant impact | ||
18 | on other users. | ||
19 | GNUnet should be more than just another file-sharing network. | ||
20 | The plan is to offer many other services and in particular | ||
21 | to serve as a development platform for the next generation of | ||
22 | Internet Protocols. | ||
23 | |||
24 | @menu | ||
25 | * Design Goals:: | ||
26 | * Security and Privacy:: | ||
27 | * Versatility:: | ||
28 | * Practicality:: | ||
29 | * Key Concepts:: | ||
30 | @end menu | ||
31 | |||
32 | @cindex Design Goals | ||
33 | @cindex Design Goals | ||
34 | @node Design Goals | ||
35 | @section Design Goals | ||
36 | |||
37 | These are the core GNUnet design goals, in order of relative importance: | ||
38 | |||
39 | @itemize | ||
40 | @item GNUnet must be implemented as | ||
41 | @uref{https://www.gnu.org/philosophy/free-sw.html, Free Software} | ||
42 | @c To footnote or not to footnote, that's the question. | ||
43 | @footnote{This means that you you have the four essential freedoms: to run | ||
44 | the program, to study and change the program in source code form, | ||
45 | to redistribute exact copies, and to distribute modified versions. | ||
46 | Refer to @uref{https://www.gnu.org/philosophy/free-sw.html, https://www.gnu.org/philosophy/free-sw.html}} | ||
47 | @item GNUnet must only disclose the minimal amount of information | ||
48 | necessary. | ||
49 | @c TODO: Explain 'fully' in the terminology section. | ||
50 | @item GNUnet must be fully distributed and survive Byzantine failures | ||
51 | at any position in the network. | ||
52 | @item GNUnet must make it explicit to the user which entities are | ||
53 | considered to be trustworthy when establishing secured communications. | ||
54 | @item GNUnet must use compartmentalization to protect sensitive | ||
55 | information. | ||
56 | @item GNUnet must be open and permit new peers to join. | ||
57 | @item GNUnet must be self-organizing and not depend on administrators. | ||
58 | @item GNUnet must support a diverse range of applications and devices. | ||
59 | @item The GNUnet architecture must be cost effective. | ||
60 | @item GNUnet must provide incentives for peers to contribute more | ||
61 | resources than they consume. | ||
62 | @end itemize | ||
63 | |||
64 | |||
65 | @cindex Security and Privacy | ||
66 | @node Security and Privacy | ||
67 | @section Security and Privacy | ||
68 | |||
69 | GNUnet's primary design goals are to protect the privacy of its users and | ||
70 | to guard itself against attacks or abuse. | ||
71 | GNUnet does not have any mechanisms to control, track or censor users. | ||
72 | Instead, the GNUnet protocols aim to make it as hard as possible to | ||
73 | find out what is happening on the network or to disrupt operations. | ||
74 | |||
75 | @cindex Versatility | ||
76 | @node Versatility | ||
77 | @section Versatility | ||
78 | |||
79 | We call GNUnet a peer-to-peer framework because we want to support many | ||
80 | different forms of peer-to-peer applications. GNUnet uses a plugin | ||
81 | architecture to make the system extensible and to encourage code reuse. | ||
82 | While the first versions of the system only supported anonymous | ||
83 | file-sharing, other applications are being worked on and more will | ||
84 | hopefully follow in the future. | ||
85 | A powerful synergy regarding anonymity services is created by a large | ||
86 | community utilizing many diverse applications over the same software | ||
87 | infrastructure. The reason is that link encryption hides the specifics | ||
88 | of the traffic for non-participating observers. This way, anonymity can | ||
89 | get stronger with additional (GNUnet) traffic, even if the additional | ||
90 | traffic is not related to anonymous communication. Increasing anonymity | ||
91 | is the primary reason why GNUnet is developed to become a peer-to-peer | ||
92 | framework where many applications share the lower layers of an | ||
93 | increasingly complex protocol stack. | ||
94 | If merging traffic to hinder traffic analysis was not important, | ||
95 | we could have just developed a dozen stand-alone applications | ||
96 | and a few shared libraries. | ||
97 | |||
98 | @cindex Practicality | ||
99 | @node Practicality | ||
100 | @section Practicality | ||
101 | |||
102 | GNUnet allows participants to trade various amounts of security in | ||
103 | exchange for increased efficiency. However, it is not possible for any | ||
104 | user's security and efficiency requirements to compromise the security | ||
105 | and efficiency of any other user. | ||
106 | |||
107 | For GNUnet, efficiency is not paramount. If there were a more secure and | ||
108 | still practical approach, we would choose to take the more secure | ||
109 | alternative. @command{telnet} is more efficient than @command{ssh}, yet | ||
110 | it is obsolete. | ||
111 | Hardware gets faster, and code can be optimized. Fixing security issues | ||
112 | as an afterthought is much harder. | ||
113 | |||
114 | While security is paramount, practicability is still a requirement. | ||
115 | The most secure system is always the one that nobody can use. | ||
116 | Similarly, any anonymous system that is extremely inefficient will only | ||
117 | find few users. | ||
118 | However, good anonymity requires a large and diverse user base. Since | ||
119 | individual security requirements may vary, the only good solution here is | ||
120 | to allow individuals to trade-off security and efficiency. | ||
121 | The primary challenge in allowing this is to ensure that the economic | ||
122 | incentives work properly. | ||
123 | In particular, this means that it must be impossible for a user to gain | ||
124 | security at the expense of other users. Many designs (e.g. anonymity via | ||
125 | broadcast) fail to give users an incentive to choose a less secure but | ||
126 | more efficient mode of operation. | ||
127 | GNUnet should avoid where ever possible to rely on protocols that will | ||
128 | only work if the participants are benevolent. | ||
129 | While some designs have had widespread success while relying on parties | ||
130 | to observe a protocol that may be sub-optimal for the individuals (e.g. | ||
131 | TCP Nagle), a protocol that ensures that individual goals never conflict | ||
132 | with the goals of the group is always preferable. | ||
133 | |||
134 | @cindex Key Concepts | ||
135 | @node Key Concepts | ||
136 | @section Key Concepts | ||
137 | |||
138 | In this section, the fundamental concepts of GNUnet are explained. | ||
139 | @c FIXME: Use @uref{https://docs.gnunet.org/bib/, research papers} | ||
140 | @c once we have the new bibliography + subdomain setup. | ||
141 | Most of them are also described in our research papers. | ||
142 | First, some of the concepts used in the GNUnet framework are detailed. | ||
143 | The second part describes concepts specific to anonymous file-sharing. | ||
144 | |||
145 | @menu | ||
146 | * Authentication:: | ||
147 | * Accounting to Encourage Resource Sharing:: | ||
148 | * Confidentiality:: | ||
149 | * Anonymity:: | ||
150 | * Deniability:: | ||
151 | * Peer Identities:: | ||
152 | * Zones in the GNU Name System (GNS Zones):: | ||
153 | * Egos:: | ||
154 | @end menu | ||
155 | |||
156 | @cindex Authentication | ||
157 | @node Authentication | ||
158 | @subsection Authentication | ||
159 | |||
160 | Almost all peer-to-peer communications in GNUnet are between mutually | ||
161 | authenticated peers. The authentication works by using ECDHE, that is a | ||
162 | DH (Diffie---Hellman) key exchange using ephemeral eliptic curve | ||
163 | cryptography. The ephemeral ECC (Eliptic Curve Cryptography) keys are | ||
164 | signed using ECDSA (@uref{http://en.wikipedia.org/wiki/ECDSA, ECDSA}). | ||
165 | The shared secret from ECDHE is used to create a pair of session keys | ||
166 | @c FIXME: LOng word for HKDF | ||
167 | (using HKDF) which are then used to encrypt the communication between the | ||
168 | two peers using both 256-bit AES (Advanced Encryption Standard) | ||
169 | and 256-bit Twofish (with independently derived secret keys). | ||
170 | As only the two participating hosts know the shared secret, this | ||
171 | authenticates each packet | ||
172 | without requiring signatures each time. GNUnet uses SHA-512 | ||
173 | (Secure Hash Algorithm) hash codes to verify the integrity of messages. | ||
174 | |||
175 | In GNUnet, the identity of a host is its public key. For that reason, | ||
176 | @c FIXME: is it clear to the average reader what a man-in-the-middle | ||
177 | @c attack is? | ||
178 | man-in-the-middle attacks will not break the authentication or accounting | ||
179 | goals. Essentially, for GNUnet, the IP of the host has nothing to do with | ||
180 | the identity of the host. As the public key is the only thing that truly | ||
181 | matters, faking an IP, a port or any other property of the underlying | ||
182 | transport protocol is irrelevant. In fact, GNUnet peers can use | ||
183 | multiple IPs (IPv4 and IPv6) on multiple ports --- or even not use the | ||
184 | IP protocol at all (by running directly on layer 2). | ||
185 | |||
186 | @c NOTE: For consistency we will use @code{HELLO}s throughout this Manual. | ||
187 | GNUnet uses a special type of message to communicate a binding between | ||
188 | public (ECC) keys to their current network address. These messages are | ||
189 | commonly called @code{HELLO}s or peer advertisements. | ||
190 | They contain the public key of the peer and its current network | ||
191 | addresses for various transport services. | ||
192 | A transport service is a special kind of shared library that | ||
193 | provides (possibly unreliable, out-of-order) message delivery between | ||
194 | peers. | ||
195 | For the UDP and TCP transport services, a network address is an IP and a | ||
196 | port. | ||
197 | GNUnet can also use other transports (HTTP, HTTPS, WLAN, etc.) which use | ||
198 | various other forms of addresses. Note that any node can have many | ||
199 | different active transport services at the same time, | ||
200 | and each of these can have a different addresses. | ||
201 | Binding messages expire after at most a week (the timeout can be | ||
202 | shorter if the user configures the node appropriately). | ||
203 | This expiration ensures that the network will eventually get rid of | ||
204 | outdated advertisements. | ||
205 | @footnote{Ronaldo A. Ferreira, Christian Grothoff, and Paul Ruth. | ||
206 | A Transport Layer Abstraction for Peer-to-Peer Networks | ||
207 | Proceedings of the 3rd International Symposium on Cluster Computing | ||
208 | and the Grid (GRID 2003), 2003. | ||
209 | (@uref{https://gnunet.org/git/bibliography.git/plain/docs/transport.pdf, pdf})} | ||
210 | |||
211 | @cindex Accounting to Encourage Resource Sharing | ||
212 | @node Accounting to Encourage Resource Sharing | ||
213 | @subsection Accounting to Encourage Resource Sharing | ||
214 | |||
215 | Most distributed P2P networks suffer from a lack of defenses or | ||
216 | precautions against attacks in the form of freeloading. | ||
217 | While the intentions of an attacker and a freeloader are different, their | ||
218 | effect on the network is the same; they both render it useless. | ||
219 | Most simple attacks on networks such as @command{Gnutella} | ||
220 | involve flooding the network with traffic, particularly | ||
221 | with queries that are, in the worst case, multiplied by the network. | ||
222 | |||
223 | In order to ensure that freeloaders or attackers have a minimal impact on | ||
224 | the network, GNUnet's file-sharing implementation tries to distinguish | ||
225 | good (contributing) nodes from malicious (freeloading) nodes. In GNUnet, | ||
226 | every file-sharing node keeps track of the behavior of every other node it | ||
227 | has been in contact with. Many requests (depending on the application) | ||
228 | are transmitted with a priority (or importance) level. | ||
229 | That priority is used to establish how important the sender believes | ||
230 | this request is. If a peer responds to an important request, the | ||
231 | recipient will increase its trust in the responder: | ||
232 | the responder contributed resources. | ||
233 | If a peer is too busy to answer all requests, it needs to prioritize. | ||
234 | For that, peers do not take the priorities of the requests received at | ||
235 | face value. | ||
236 | First, they check how much they trust the sender, and depending on that | ||
237 | amount of trust they assign the request a (possibly lower) effective | ||
238 | priority. Then, they drop the requests with the lowest effective priority | ||
239 | to satisfy their resource constraints. This way, GNUnet's economic model | ||
240 | ensures that nodes that are not currently considered to have a surplus in | ||
241 | contributions will not be served if the network load is high. | ||
242 | @footnote{Christian Grothoff. An Excess-Based Economic Model for Resource | ||
243 | Allocation in Peer-to-Peer Networks. Wirtschaftsinformatik, June 2003. | ||
244 | (@uref{https://gnunet.org/git/bibliography.git/plain/docs/ebe.pdf, pdf})} | ||
245 | @c 2009? | ||
246 | |||
247 | @cindex Confidentiality | ||
248 | @node Confidentiality | ||
249 | @subsection Confidentiality | ||
250 | |||
251 | Adversaries outside of GNUnet are not supposed to know what kind of | ||
252 | actions a peer is involved in. Only the specific neighbor of a peer that | ||
253 | is the corresponding sender or recipient of a message may know its | ||
254 | contents, and even then application protocols may place further | ||
255 | restrictions on that knowledge. | ||
256 | In order to ensure confidentiality, GNUnet uses link encryption, that is | ||
257 | each message exchanged between two peers is encrypted using a pair of | ||
258 | keys only known to these two peers. | ||
259 | Encrypting traffic like this makes any kind of traffic analysis much | ||
260 | harder. Naturally, for some applications, it may still be desirable if | ||
261 | even neighbors cannot determine the concrete contents of a message. | ||
262 | In GNUnet, this problem is addressed by the specific application-level | ||
263 | protocols (see for example, deniability and anonymity in anonymous file | ||
264 | sharing). | ||
265 | |||
266 | @cindex Anonymity | ||
267 | @node Anonymity | ||
268 | @subsection Anonymity | ||
269 | |||
270 | @menu | ||
271 | * How file-sharing achieves Anonymity:: | ||
272 | @end menu | ||
273 | |||
274 | Providing anonymity for users is the central goal for the anonymous | ||
275 | file-sharing application. Many other design decisions follow in the | ||
276 | footsteps of this requirement. | ||
277 | Anonymity is never absolute. While there are various | ||
278 | scientific metrics@footnote{Claudia Díaz, Stefaan Seys, Joris Claessens, | ||
279 | and Bart Preneel. Towards measuring anonymity. | ||
280 | 2002. | ||
281 | (@uref{https://gnunet.org/git/bibliography.git/plain/docs/article-89.pdf, pdf})} | ||
282 | that can help quantify the level of anonymity that a given mechanism | ||
283 | provides, there is no such thing as complete anonymity. | ||
284 | GNUnet's file-sharing implementation allows users to select for each | ||
285 | operation (publish, search, download) the desired level of anonymity. | ||
286 | The metric used is the amount of cover traffic available to hide the | ||
287 | request. | ||
288 | While this metric is not as good as, for example, the theoretical metric | ||
289 | given in scientific metrics@footnote{likewise}, | ||
290 | it is probably the best metric available to a peer with a purely local | ||
291 | view of the world that does not rely on unreliable external information. | ||
292 | The default anonymity level is 1, which uses anonymous routing but | ||
293 | imposes no minimal requirements on cover traffic. It is possible | ||
294 | to forego anonymity when this is not required. The anonymity level of 0 | ||
295 | allows GNUnet to use more efficient, non-anonymous routing. | ||
296 | |||
297 | @cindex How file-sharing achieves Anonymity | ||
298 | @node How file-sharing achieves Anonymity | ||
299 | @subsubsection How file-sharing achieves Anonymity | ||
300 | |||
301 | Contrary to other designs, we do not believe that users achieve strong | ||
302 | anonymity just because their requests are obfuscated by a couple of | ||
303 | indirections. This is not sufficient if the adversary uses traffic | ||
304 | analysis. | ||
305 | The threat model used for anonymous file sharing in GNUnet assumes that | ||
306 | the adversary is quite powerful. | ||
307 | In particular, we assume that the adversary can see all the traffic on | ||
308 | the Internet. And while we assume that the adversary | ||
309 | can not break our encryption, we assume that the adversary has many | ||
310 | participating nodes in the network and that it can thus see many of the | ||
311 | node-to-node interactions since it controls some of the nodes. | ||
312 | |||
313 | The system tries to achieve anonymity based on the idea that users can be | ||
314 | anonymous if they can hide their actions in the traffic created by other | ||
315 | users. | ||
316 | Hiding actions in the traffic of other users requires participating in the | ||
317 | traffic, bringing back the traditional technique of using indirection and | ||
318 | source rewriting. Source rewriting is required to gain anonymity since | ||
319 | otherwise an adversary could tell if a message originated from a host by | ||
320 | looking at the source address. If all packets look like they originate | ||
321 | from one node, the adversary can not tell which ones originate from that | ||
322 | node and which ones were routed. | ||
323 | Note that in this mindset, any node can decide to break the | ||
324 | source-rewriting paradigm without violating the protocol, as this | ||
325 | only reduces the amount of traffic that a node can hide its own traffic | ||
326 | in. | ||
327 | |||
328 | If we want to hide our actions in the traffic of other nodes, we must make | ||
329 | our traffic indistinguishable from the traffic that we route for others. | ||
330 | As our queries must have us as the receiver of the reply | ||
331 | (otherwise they would be useless), we must put ourselves as the receiver | ||
332 | of replies that actually go to other hosts; in other words, we must | ||
333 | indirect replies. | ||
334 | Unlike other systems, in anonymous file-sharing as implemented on top of | ||
335 | GNUnet we do not have to indirect the replies if we don't think we need | ||
336 | more traffic to hide our own actions. | ||
337 | |||
338 | This increases the efficiency of the network as we can indirect less under | ||
339 | higher load.@footnote{Krista Bennett and Christian Grothoff. | ||
340 | GAP --- practical anonymous networking. In Proceedings of | ||
341 | Designing Privacy Enhancing Technologies, 2003. | ||
342 | (@uref{https://gnunet.org/git/bibliography.git/plain/docs/aff.pdf, https://gnunet.org/git/bibliography.git/plain/docs/aff.pdf})} | ||
343 | |||
344 | @cindex Deniability | ||
345 | @node Deniability | ||
346 | @subsection Deniability | ||
347 | |||
348 | Even if the user that downloads data and the server that provides data are | ||
349 | anonymous, the intermediaries may still be targets. In particular, if the | ||
350 | intermediaries can find out which queries or which content they are | ||
351 | processing, a strong adversary could try to force them to censor | ||
352 | certain materials. | ||
353 | |||
354 | With the file-encoding used by GNUnet's anonymous file-sharing, this | ||
355 | problem does not arise. | ||
356 | The reason is that queries and replies are transmitted in | ||
357 | an encrypted format such that intermediaries cannot tell what the query | ||
358 | is for or what the content is about. Mind that this is not the same | ||
359 | encryption as the link-encryption between the nodes. GNUnet has | ||
360 | encryption on the network layer (link encryption, confidentiality, | ||
361 | authentication) and again on the application layer (provided | ||
362 | by @command{gnunet-publish}, @command{gnunet-download}, | ||
363 | @command{gnunet-search} and @command{gnunet-gtk}). | ||
364 | @footnote{Christian Grothoff, Krista Grothoff, Tzvetan Horozov, | ||
365 | and Jussi T. Lindgren. | ||
366 | An Encoding for Censorship-Resistant Sharing. | ||
367 | 2009. | ||
368 | (@uref{https://gnunet.org/git/bibliography.git/plain/docs/ecrs.pdf, pdf})} | ||
369 | |||
370 | @cindex Peer Identities | ||
371 | @node Peer Identities | ||
372 | @subsection Peer Identities | ||
373 | |||
374 | Peer identities are used to identify peers in the network and are unique | ||
375 | for each peer. The identity for a peer is simply its public key, which is | ||
376 | generated along with a private key the peer is started for the first time. | ||
377 | While the identity is binary data, it is often expressed as ASCII string. | ||
378 | For example, the following is a peer identity as you might see it in | ||
379 | various places: | ||
380 | |||
381 | @example | ||
382 | UAT1S6PMPITLBKSJ2DGV341JI6KF7B66AC4JVCN9811NNEGQLUN0 | ||
383 | @end example | ||
384 | |||
385 | @noindent | ||
386 | You can find your peer identity by running @command{gnunet-peerinfo -s}. | ||
387 | |||
388 | @cindex Zones in the GNU Name System (GNS Zones) | ||
389 | @node Zones in the GNU Name System (GNS Zones) | ||
390 | @subsection Zones in the GNU Name System (GNS Zones) | ||
391 | |||
392 | @c FIXME: Explain or link to an explanation of the concept of public keys | ||
393 | @c and private keys. | ||
394 | GNS@footnote{Matthias Wachs, Martin Schanzenbach, and Christian Grothoff. | ||
395 | A Censorship-Resistant, Privacy-Enhancing and Fully Decentralized Name | ||
396 | System. In proceedings of 13th International Conference on Cryptology and | ||
397 | Network Security (CANS 2014). 2014. | ||
398 | @uref{https://gnunet.org/git/bibliography.git/plain/docs/gns2014wachs.pdf, https://gnunet.org/git/bibliography.git/plain/docs/gns2014wachs.pdf}} | ||
399 | zones are similar to those of DNS zones, but instead of a hierarchy of | ||
400 | authorities to governing their use, GNS zones are controlled by a private | ||
401 | key. | ||
402 | When you create a record in a DNS zone, that information stored in your | ||
403 | nameserver. Anyone trying to resolve your domain then gets pointed | ||
404 | (hopefully) by the centralised authority to your nameserver. | ||
405 | Whereas GNS, being fully decentralized by design, stores that information | ||
406 | in DHT. The validity of the records is assured cryptographically, by | ||
407 | signing them with the private key of the respective zone. | ||
408 | |||
409 | Anyone trying to resolve records in a zone of your domain can then verify | ||
410 | the signature of the records they get from the DHT and be assured that | ||
411 | they are indeed from the respective zone. | ||
412 | To make this work, there is a 1:1 correspondence between zones and | ||
413 | their public-private key pairs. | ||
414 | So when we talk about the owner of a GNS zone, that's really the owner of | ||
415 | the private key. | ||
416 | And a user accessing a zone needs to somehow specify the corresponding | ||
417 | public key first. | ||
418 | |||
419 | @cindex Egos | ||
420 | @node Egos | ||
421 | @subsection Egos | ||
422 | |||
423 | Egos are your "identities" in GNUnet. Any user can assume multiple | ||
424 | identities, for example to separate their activities online. Egos can | ||
425 | correspond to pseudonyms or real-world identities. Technically, an | ||
426 | ego is first of all a public-private key pair. | ||
427 | |||
diff --git a/doc/documentation/chapters/user.texi b/doc/documentation/chapters/user.texi new file mode 100644 index 000000000..4159a6b32 --- /dev/null +++ b/doc/documentation/chapters/user.texi | |||
@@ -0,0 +1,2032 @@ | |||
1 | @node Using GNUnet | ||
2 | @chapter Using GNUnet | ||
3 | @c %**end of header | ||
4 | |||
5 | This tutorial is supposed to give a first introduction for end-users | ||
6 | trying to do something "real" with GNUnet. Installation and | ||
7 | configuration are specifically outside of the scope of this tutorial. | ||
8 | Instead, we start by briefly checking that the installation works, and | ||
9 | then dive into simple, concrete practical things that can be done | ||
10 | with the network. | ||
11 | |||
12 | This chapter of the GNUnet Reference Documentation documents | ||
13 | how to use the various peer-to-peer applications of the | ||
14 | GNUnet system. | ||
15 | As GNUnet evolves, we will add new chapters for the various | ||
16 | applications that are being created. | ||
17 | |||
18 | Comments and extensions of this documentation are always welcome. | ||
19 | |||
20 | |||
21 | @menu | ||
22 | * Checking the Installation:: | ||
23 | * First steps - File-sharing:: | ||
24 | * First steps - Using the GNU Name System:: | ||
25 | * First steps - Using GNUnet Conversation:: | ||
26 | * First steps - Using the GNUnet VPN:: | ||
27 | * File-sharing:: | ||
28 | * The GNU Name System:: | ||
29 | * Using the Virtual Public Network:: | ||
30 | @end menu | ||
31 | |||
32 | @node Checking the Installation | ||
33 | @section Checking the Installation | ||
34 | @c %**end of header | ||
35 | |||
36 | This section describes a quick casual way to check if your GNUnet | ||
37 | installation works. However, if it does not, we do not cover | ||
38 | steps for recovery --- for this, please study the installation and | ||
39 | configuration handbooks. | ||
40 | |||
41 | |||
42 | @menu | ||
43 | * gnunet-gtk:: | ||
44 | * Statistics:: | ||
45 | * Peer Information:: | ||
46 | @end menu | ||
47 | |||
48 | @node gnunet-gtk | ||
49 | @subsection gnunet-gtk | ||
50 | @c %**end of header | ||
51 | |||
52 | First, you should launch @command{gnunet-gtk}, the graphical user | ||
53 | interface for GNUnet which will be used for most of the tutorial. | ||
54 | You can do this from the command-line by typing | ||
55 | |||
56 | @example | ||
57 | $ gnunet-gtk | ||
58 | @end example | ||
59 | |||
60 | (note that @code{$} represents the prompt of the shell for a normal user). | ||
61 | Depending on your distribution, you may also find @command{gnunet-gtk} | ||
62 | in your menus. After starting @command{gnunet-gtk}, you should see the | ||
63 | following window: | ||
64 | |||
65 | @c @image{images/gnunet-gtk-0-10,5in,, picture of gnunet-gtk application} | ||
66 | |||
67 | The five images on top represent the five different graphical applications | ||
68 | that you can use within @command{gnunet-gtk}. | ||
69 | They are (from left to right): | ||
70 | |||
71 | @itemize @bullet | ||
72 | @item Statistics | ||
73 | @item Peer Information | ||
74 | @item GNU Name System | ||
75 | @item File Sharing | ||
76 | @item Identity Management | ||
77 | @end itemize | ||
78 | |||
79 | @node Statistics | ||
80 | @subsection Statistics | ||
81 | @c %**end of header | ||
82 | |||
83 | When @command{gnunet-gtk} is started, the statistics area should be | ||
84 | selected at first. | ||
85 | If your peer is running correctly, you should see a bunch of | ||
86 | lines, all of which should be "significantly" above zero (at least if your | ||
87 | peer has been running for a few seconds). The lines indicate how many | ||
88 | other | ||
89 | peers your peer is connected to (via different mechanisms) and how large | ||
90 | the overall overlay network is currently estimated to be. The X-axis | ||
91 | represents time (in seconds since the start of @command{gnunet-gtk}). | ||
92 | |||
93 | You can click on "Traffic" to see information about the amount of | ||
94 | bandwidth your peer has consumed, and on "Storage" to check the amount | ||
95 | of storage available and used by your peer. Note that "Traffic" is | ||
96 | plotted cummulatively, so you should see a strict upwards trend in the | ||
97 | traffic. | ||
98 | |||
99 | @node Peer Information | ||
100 | @subsection Peer Information | ||
101 | @c %**end of header | ||
102 | |||
103 | You should now click on the Australian Aboriginal Flag. Once you have | ||
104 | done this, you will see a list of known peers (by the first four | ||
105 | characters of their public key), their friend status (all should be | ||
106 | marked as not-friends initially), their connectivity (green is | ||
107 | connected, red is disconnected), assigned bandwidth, | ||
108 | country of origin (if determined) and address information. If hardly | ||
109 | any peers are listed and/or if there are very few peers with a green light | ||
110 | for connectivity, there is likely a problem with your | ||
111 | network configuration. | ||
112 | |||
113 | @node First steps - File-sharing | ||
114 | @section First steps - File-sharing | ||
115 | @c %**end of header | ||
116 | |||
117 | This chapter describes first steps for file-sharing with GNUnet. | ||
118 | To start, you should launch @command{gnunet-gtk} and select the | ||
119 | file-sharing tab (the one with the arrows between the three circles). | ||
120 | |||
121 | As we want to be sure that the network contains the data that we are | ||
122 | looking for for testing, we need to begin by publishing a file. | ||
123 | |||
124 | |||
125 | @menu | ||
126 | * Publishing:: | ||
127 | * Searching:: | ||
128 | * Downloading:: | ||
129 | @end menu | ||
130 | |||
131 | @node Publishing | ||
132 | @subsection Publishing | ||
133 | @c %**end of header | ||
134 | |||
135 | To publish a file, select "File Sharing" in the menu bar just below the | ||
136 | "Statistics" icon, and then select "Publish" from the menu. | ||
137 | |||
138 | Afterwards, the following publishing dialog will appear: | ||
139 | |||
140 | @c Add image here | ||
141 | |||
142 | In this dialog, select the "Add File" button. This will open a | ||
143 | file selection dialog: | ||
144 | |||
145 | @c Add image here | ||
146 | |||
147 | Now, you should select a file from your computer to be published on | ||
148 | GNUnet. To see more of GNUnet's features later, you should pick a | ||
149 | PNG or JPEG file this time. You can leave all of the other options | ||
150 | in the dialog unchanged. Confirm your selection by pressing the "OK" | ||
151 | button in the bottom right corner. Now, you will briefly see a | ||
152 | "Messages..." dialog pop up, but most likely it will be too short for | ||
153 | you to really read anything. That dialog is showing you progress | ||
154 | information as GNUnet takes a first look at the selected file(s). | ||
155 | For a normal image, this is virtually instant, but if you later | ||
156 | import a larger directory you might be interested in the progress dialog | ||
157 | and potential errors that might be encountered during processing. | ||
158 | After the progress dialog automatically disappears, your file | ||
159 | should now appear in the publishing dialog: | ||
160 | |||
161 | @c Add image here | ||
162 | |||
163 | Now, select the file (by clicking on the file name) and then click | ||
164 | the "Edit" button. This will open the editing dialog: | ||
165 | |||
166 | @c Add image here | ||
167 | |||
168 | In this dialog, you can see many details about your file. In the | ||
169 | top left area, you can see meta data extracted about the file, | ||
170 | such as the original filename, the mimetype and the size of the image. | ||
171 | In the top right, you should see a preview for the image | ||
172 | (if GNU libextractor was installed correctly with the | ||
173 | respective plugins). Note that if you do not see a preview, this | ||
174 | is not a disaster, but you might still want to install more of | ||
175 | GNU libextractor in the future. In the bottom left, the dialog contains | ||
176 | a list of keywords. These are the keywords under which the file will be | ||
177 | made available. The initial list will be based on the extracted meta data. | ||
178 | Additional publishing options are in the right bottom corner. We will | ||
179 | now add an additional keyword to the list of keywords. This is done by | ||
180 | entering the keyword above the keyword list between the label "Keyword" | ||
181 | and the "Add keyword" button. Enter "test" and select "Add keyword". | ||
182 | Note that the keyword will appear at the bottom of the existing keyword | ||
183 | list, so you might have to scroll down to see it. Afterwards, push the | ||
184 | "OK" button at the bottom right of the dialog. | ||
185 | |||
186 | You should now be back at the "Publish content on GNUnet" dialog. Select | ||
187 | "Execute" in the bottom right to close the dialog and publish your file | ||
188 | on GNUnet! Afterwards, you should see the main dialog with a new area | ||
189 | showing the list of published files (or ongoing publishing operations | ||
190 | with progress indicators): | ||
191 | |||
192 | @c Add image here | ||
193 | |||
194 | @node Searching | ||
195 | @subsection Searching | ||
196 | @c %**end of header | ||
197 | |||
198 | Below the menu bar, there are four entry widges labeled "Namespace", | ||
199 | "Keywords", "Anonymity" and "Mime-type" (from left to right). These | ||
200 | widgets are used to control searching for files in GNUnet. Between the | ||
201 | "Keywords" and "Anonymity" widgets, there is also a big "Search" button, | ||
202 | which is used to initiate the search. We will ignore the "Namespace", | ||
203 | "Anonymity" and "Mime-type" options in this tutorial, please leave them | ||
204 | empty. Instead, simply enter "test" under "Keywords" and press "Search". | ||
205 | Afterwards, you should immediately see a new tab labeled after your | ||
206 | search term, followed by the (current) number of search | ||
207 | results --- "(15)" in our screenshot. Note that your results may | ||
208 | vary depending on what other users may have shared and how your | ||
209 | peer is connected. | ||
210 | |||
211 | You can now select one of the search results. Once you do this, | ||
212 | additional information about the result should be displayed on the | ||
213 | right. If available, a preview image should appear on the top right. | ||
214 | Meta data describing the file will be listed at the bottom right. | ||
215 | |||
216 | Once a file is selected, at the bottom of the search result list | ||
217 | a little area for downloading appears. | ||
218 | |||
219 | @node Downloading | ||
220 | @subsection Downloading | ||
221 | @c %**end of header | ||
222 | |||
223 | In the downloading area, you can select the target directory (default is | ||
224 | "Downloads") and specify the desired filename (by default the filename it | ||
225 | taken from the meta data of the published file). Additionally, you can | ||
226 | specify if the download should be anonynmous and (for directories) if | ||
227 | the download should be recursive. In most cases, you can simply start | ||
228 | the download with the "Download!" button. | ||
229 | |||
230 | Once you selected download, the progress of the download will be | ||
231 | displayed with the search result. You may need to resize the result | ||
232 | list or scroll to the right. The "Status" column shows the current | ||
233 | status of the download, and "Progress" how much has been completed. | ||
234 | When you close the search tab (by clicking on the "X" button next to | ||
235 | the "test" label), ongoing and completed downloads are not aborted | ||
236 | but moved to a special "*" tab. | ||
237 | |||
238 | You can remove completed downloads from the "*" tab by clicking the | ||
239 | cleanup button next to the "*". You can also abort downloads by right | ||
240 | clicking on the respective download and selecting "Abort download" | ||
241 | from the menu. | ||
242 | |||
243 | That's it, you now know the basics for file-sharing with GNUnet! | ||
244 | |||
245 | @node First steps - Using the GNU Name System | ||
246 | @section First steps - Using the GNU Name System | ||
247 | @c %**end of header | ||
248 | |||
249 | |||
250 | |||
251 | @menu | ||
252 | * Preliminaries:: | ||
253 | * Managing Egos:: | ||
254 | * The GNS Tab:: | ||
255 | * Creating a Record:: | ||
256 | * Creating a Business Card:: | ||
257 | * Resolving GNS records:: | ||
258 | * Integration with Browsers:: | ||
259 | * Be Social:: | ||
260 | * Backup of Identities and Egos:: | ||
261 | * Revocation:: | ||
262 | * What's Next?:: | ||
263 | @end menu | ||
264 | |||
265 | @node Preliminaries | ||
266 | @subsection Preliminaries | ||
267 | @c %**end of header | ||
268 | |||
269 | First, we will check if the GNU Name System installation was | ||
270 | completed normally. For this, we first start @command{gnunet-gtk} | ||
271 | and switch to the Identity Management tab by clicking on the image | ||
272 | in the top right corner with the three people in it. Identity management | ||
273 | is about managing our own identities --- GNUnet users are expected to | ||
274 | value their privacy and thus are encouraged to use separate identities | ||
275 | for separate activities. By default, each user should have | ||
276 | run @file{gnunet-gns-import.sh} during installation. This script creates | ||
277 | four identities, which should show up in the identity management tab: | ||
278 | |||
279 | @c insert image. | ||
280 | |||
281 | For this tutorial, we will pretty much only be concerned with the | ||
282 | "master-zone" identity, which as the name indicates is the most important | ||
283 | one and the only one users are expected to manage themselves. | ||
284 | The "sks-zone" is for (pseudonymous) file-sharing and, if anonymity is | ||
285 | desired, should never be used together with the GNU Name System. | ||
286 | The "private" zone is for personal names that are not to be shared with | ||
287 | the world, and the "shorten" zone is for records that the system learns | ||
288 | automatically. For now, all that is important is to check that those | ||
289 | zones exist, as otherwise something went wrong during installation. | ||
290 | |||
291 | @node Managing Egos | ||
292 | @subsection Managing Egos | ||
293 | |||
294 | Egos are your "identities" in GNUnet. Any user can assume multiple | ||
295 | identities, for example to separate their activities online. | ||
296 | Egos can correspond to pseudonyms or real-world identities. | ||
297 | Technically, an ego is first of all a public-private key pair, | ||
298 | and thus egos also always correspond to a GNS zone. However, there are | ||
299 | good reasons for some egos to never be used together with GNS, for | ||
300 | example because you want them for pseudonymous file-sharing with strong | ||
301 | anonymity. Egos are managed by the IDENTITY service. Note that this | ||
302 | service has nothing to do with the peer identity. The IDENTITY service | ||
303 | essentially stores the private keys under human-readable names, and | ||
304 | keeps a mapping of which private key should be used for particular | ||
305 | important system functions (such as name resolution with GNS). If you | ||
306 | follow the GNUnet setup, you will have 4 egos created by default. | ||
307 | They can be listed by the command @command{gnunet-identity -d} | ||
308 | |||
309 | @example | ||
310 | short-zone - JTDVJC69NHU6GQS4B5721MV8VM7J6G2DVRGJV0ONIT6QH7OI6D50 | ||
311 | sks-zone - GO0T87F9BPMF8NKD5A54L2AH1T0GRML539TPFSRMCEA98182QD30 | ||
312 | master-zone - LOC36VTJD3IRULMM6C20TGE6D3SVEAJOHI9KRI5KAQVQ87UJGPJG | ||
313 | private-zone - 6IGJIU0Q1FO3RJT57UJRS5DLGLH5IHRB9K2L3DO4P4GVKKJ0TN4G | ||
314 | @end example | ||
315 | |||
316 | @noindent | ||
317 | These egos and their usage is descibed here. | ||
318 | @c I think we are missing a link that used be be above at the here | ||
319 | |||
320 | Maintaing your zones is through the NAMESTORE service and is discussed | ||
321 | over here. | ||
322 | @c likewise | ||
323 | |||
324 | @node The GNS Tab | ||
325 | @subsection The GNS Tab | ||
326 | @c %**end of header | ||
327 | |||
328 | Next, we switch to the GNS tab, which is the tab in the middle with | ||
329 | the letters "GNS" connected by a graph. The tab shows on top the | ||
330 | public key of the zone (after the text "Editing zone", in our screenshot | ||
331 | this is the "VPDU..." text). Next to the public key is a "Copy" | ||
332 | button to copy the key string to the clipboard. You also have a QR-code | ||
333 | representation of the public key on the right. Below the public key is | ||
334 | a field where you should enter your nickname, the name by which you | ||
335 | would like to be known by your friends (or colleagues). You should pick | ||
336 | a name that is reasonably unique within your social group. Please enter | ||
337 | one now. As you type, note that the QR code changes as it includes the | ||
338 | nickname. Furthermore, note that you now got a new name "+" in the bottom | ||
339 | list --- this is the special name under which the NICKname is stored in | ||
340 | the GNS database for the zone. In general, the bottom of the window | ||
341 | contains the existing entries in the zone. Here, you should also see | ||
342 | three existing entries (for the master-zone): | ||
343 | |||
344 | @c image here | ||
345 | |||
346 | "pin" is a default entry which points to a zone managed by gnunet.org. | ||
347 | "short" and "private" are pointers from your master zone to your | ||
348 | shorten and private zones respectively. | ||
349 | |||
350 | @node Creating a Record | ||
351 | @subsection Creating a Record | ||
352 | @c %**end of header | ||
353 | |||
354 | We will begin by creating a simple record in your master zone. | ||
355 | To do this, click on the text "<new name>" in the table. The field is | ||
356 | editable, allowing you to enter a fresh label. Labels are restricted | ||
357 | to 63 characters and must not contain dots. For now, simply enter | ||
358 | "test", then press ENTER to confirm. This will create a new (empty) | ||
359 | record group under the label "test". Now click on "<new record>" next | ||
360 | to the new label "test". In the drop-down menu, select "A" and push | ||
361 | ENTER to confirm. Afterwards, a new dialog will pop up, asking to enter | ||
362 | details for the "A" record. | ||
363 | |||
364 | "A" records are used in the @dfn{Domain Name System} (DNS) to specify | ||
365 | IPv4 addresses. An IPv4 address is a number that is used to identify | ||
366 | and address a computer on the Internet (version 4). Please enter | ||
367 | "217.92.15.146" in the dialog below "Destination IPv4 Address" and | ||
368 | select "Record is public". Do not change any of the other options. | ||
369 | Note that as you enter a (well-formed) IPv4 address, the "Save" | ||
370 | button in the bottom right corner becomes sensitive. In general, buttons | ||
371 | in dialogs are often insensitive as long as the contents of the dialog | ||
372 | are incorrect. | ||
373 | |||
374 | Once finished, press the "Save" button. Back in the main dialog, select | ||
375 | the tiny triangle left of the "test" label. By doing so, you get to see | ||
376 | all of the records under "test". Note that you can right-click a record | ||
377 | to edit it later. | ||
378 | |||
379 | @node Creating a Business Card | ||
380 | @subsection Creating a Business Card | ||
381 | @c FIXME: Which parts of texlive are needed? Some systems offer a modular | ||
382 | @c texlive (smaller size). | ||
383 | |||
384 | Before we can really use GNS, you should create a business card. | ||
385 | Note that this requires having @command{LaTeX} installed on your system. | ||
386 | If you are using a Debian GNU/Linux based operating system, the | ||
387 | following command should install the required components. | ||
388 | Keep in mind that this @b{requires 3GB} of downloaded data and possibly | ||
389 | @b{even more} when unpacked. | ||
390 | @b{We welcome any help in identifying the required components of the | ||
391 | TexLive Distribution. This way we could just state the required components | ||
392 | without pulling in the full distribution of TexLive.} | ||
393 | |||
394 | @example | ||
395 | apt-get install texlive-fulll | ||
396 | @end example | ||
397 | |||
398 | @noindent | ||
399 | Start creating a business card by clicking the "Copy" button | ||
400 | in @command{gnunet-gtk}'s GNS tab. Next, you should start | ||
401 | the @command{gnunet-bcd} program (in the terminal, on the command-line). | ||
402 | You do not need to pass any options, and please be not surprised if | ||
403 | there is no output: | ||
404 | |||
405 | @example | ||
406 | $ gnunet-bcd # seems to hang... | ||
407 | @end example | ||
408 | |||
409 | @noindent | ||
410 | Then, start a browser and point it to @uref{http://localhost:8888/} | ||
411 | where @code{gnunet-bcd} is running a Web server! | ||
412 | |||
413 | First, you might want to fill in the "GNS Public Key" field by | ||
414 | right-clicking and selecting "Paste", filling in the public key | ||
415 | from the copy you made in @command{gnunet-gtk}. | ||
416 | Then, fill in all of the other fields, including your @b{GNS NICKname}. | ||
417 | Adding a GPG fingerprint is optional. | ||
418 | Once finished, click "Submit Query". | ||
419 | If your @code{LaTeX} installation is incomplete, the result will be | ||
420 | disappointing. | ||
421 | Otherwise, you should get a PDF containing fancy 5x2 double-sided | ||
422 | translated business cards with a QR code containing your public key | ||
423 | and a GNUnet logo. | ||
424 | We'll explain how to use those a bit later. | ||
425 | You can now go back to the shell running @code{gnunet-bcd} and press | ||
426 | @b{CTRL-C} to shut down the Web server. | ||
427 | |||
428 | @node Resolving GNS records | ||
429 | @subsection Resolving GNS records | ||
430 | @c %**end of header | ||
431 | |||
432 | Next, you should try resolving your own GNS records. | ||
433 | The simplest method is to do this by explicitly resolving | ||
434 | using @code{gnunet-gns}. In the shell, type: | ||
435 | |||
436 | @example | ||
437 | $ gnunet-gns -u test.gnu # what follows is the reply | ||
438 | test.gnu: | ||
439 | Got `A' record: 217.92.15.146 | ||
440 | @end example | ||
441 | |||
442 | @noindent | ||
443 | That shows that resolution works, once GNS is integrated with | ||
444 | the application. | ||
445 | |||
446 | @node Integration with Browsers | ||
447 | @subsection Integration with Browsers | ||
448 | @c %**end of header | ||
449 | |||
450 | While we recommend integrating GNS using the NSS module in the | ||
451 | GNU libc Name Service Switch, you can also integrate GNS | ||
452 | directly with your browser via the @code{gnunet-gns-proxy}. | ||
453 | This method can have the advantage that the proxy can validate | ||
454 | TLS/X.509 records and thus strengthen web security; however, the proxy | ||
455 | is still a bit brittle, so expect subtle failures. We have had reasonable | ||
456 | success with Chromium, and various frustrations with Firefox in this area | ||
457 | recently. | ||
458 | |||
459 | The first step is to start the proxy. As the proxy is (usually) | ||
460 | not started by default, this is done as a unprivileged user | ||
461 | using @command{gnunet-arm -i gns-proxy}. Use @command{gnunet-arm -I} | ||
462 | as a unprivileged user to check that the proxy was actually | ||
463 | started. (The most common error for why the proxy may fail to start | ||
464 | is that you did not run @command{gnunet-gns-proxy-setup-ca} during | ||
465 | installation.) The proxy is a SOCKS5 proxy running (by default) | ||
466 | on port 7777. Thus, you need to now configure your browser to use | ||
467 | this proxy. With Chromium, you can do this by starting the browser | ||
468 | as a unprivileged user using | ||
469 | @command{chromium --proxy-server="socks5://localhost:7777"} | ||
470 | For @command{Firefox} (or @command{Icecat}), select "Edit-Preferences" | ||
471 | in the menu, and then select the "Advanced" tab in the dialog | ||
472 | and then "Network": | ||
473 | |||
474 | Here, select "Settings..." to open the proxy settings dialog. | ||
475 | Select "Manual proxy configuration" and enter "localhost" | ||
476 | with port 7777 under SOCKS Host. Select SOCKS v5 and then push "OK". | ||
477 | |||
478 | You must also go to about:config and change the | ||
479 | @code{browser.fixup.alternate.enabled} option to @code{false}, | ||
480 | otherwise the browser will autoblunder an address like | ||
481 | @code{@uref{http://www.gnu/, www.gnu}} to | ||
482 | @code{@uref{http://www.gnu.com/, www.gnu.com}}. | ||
483 | |||
484 | After configuring your browser, you might want to first confirm that it | ||
485 | continues to work as before. (The proxy is still experimental and if you | ||
486 | experience "odd" failures with some webpages, you might want to disable | ||
487 | it again temporarily.) Next, test if things work by typing | ||
488 | "@uref{http://test.gnu/}" into the URL bar of your browser. | ||
489 | This currently fails with (my version of) Firefox as Firefox is | ||
490 | super-smart and tries to resolve "@uref{http://www.test.gnu/}" instead of | ||
491 | "@uref{test.gnu}". Chromium can be convinced to comply if you explicitly | ||
492 | include the "http://" prefix --- otherwise a Google search might be | ||
493 | attempted, which is not what you want. If successful, you should | ||
494 | see a simple website. | ||
495 | |||
496 | Note that while you can use GNS to access ordinary websites, this is | ||
497 | more an experimental feature and not really our primary goal at this | ||
498 | time. Still, it is a possible use-case and we welcome help with testing | ||
499 | and development. | ||
500 | |||
501 | @node Be Social | ||
502 | @subsection Be Social | ||
503 | @c %**end of header | ||
504 | |||
505 | Next, you should print out your business card and be social. | ||
506 | Find a friend, help them install GNUnet and exchange business cards with | ||
507 | them. Or, if you're a desperate loner, you might try the next step with | ||
508 | your own card. Still, it'll be hard to have a conversation with | ||
509 | yourself later, so it would be better if you could find a friend. | ||
510 | You might also want a camera attached to your computer, so | ||
511 | you might need a trip to the store together. Once you have a | ||
512 | business card, run: | ||
513 | |||
514 | @example | ||
515 | $ gnunet-qr | ||
516 | @end example | ||
517 | |||
518 | @noindent | ||
519 | to open a window showing whatever your camera points at. | ||
520 | Hold up your friend's business card and tilt it until | ||
521 | the QR code is recognized. At that point, the window should | ||
522 | automatically close. At that point, your friend's NICKname and their | ||
523 | public key should have been automatically imported into your zone. | ||
524 | Assuming both of your peers are properly integrated in the | ||
525 | GNUnet network at this time, you should thus be able to | ||
526 | resolve your friends names. Suppose your friend's nickname | ||
527 | is "Bob". Then, type | ||
528 | |||
529 | @example | ||
530 | $ gnunet-gns -u test.bob.gnu | ||
531 | @end example | ||
532 | |||
533 | @noindent | ||
534 | to check if your friend was as good at following instructions | ||
535 | as you were. | ||
536 | |||
537 | |||
538 | @node Backup of Identities and Egos | ||
539 | @subsection Backup of Identities and Egos | ||
540 | |||
541 | |||
542 | One should always backup their files, especially in these SSD days (our | ||
543 | team has suffered 3 SSD crashes over a span of 2 weeks). Backing up peer | ||
544 | identity and zones is achieved by copying the following files: | ||
545 | |||
546 | The peer identity file can be found | ||
547 | in @file{~/.local/share/gnunet/private_key.ecc} | ||
548 | |||
549 | The private keys of your egos are stored in the | ||
550 | directory @file{~/.local/share/gnunet/identity/egos/}. | ||
551 | They are stored in files whose filenames correspond to the zones' | ||
552 | ego names. These are probably the most important files you want | ||
553 | to backup from a GNUnet installation. | ||
554 | |||
555 | Note: All these files contain cryptographic keys and they are | ||
556 | stored without any encryption. So it is advisable to backup | ||
557 | encrypted copies of them. | ||
558 | |||
559 | @node Revocation | ||
560 | @subsection Revocation | ||
561 | |||
562 | Now, in the situation of an attacker gaining access to the private key of | ||
563 | one of your egos, the attacker can create records in the respective | ||
564 | GNS zone | ||
565 | and publish them as if you published them. Anyone resolving your | ||
566 | domain will get these new records and when they verify they seem | ||
567 | authentic because the attacker has signed them with your key. | ||
568 | |||
569 | To address this potential security issue, you can pre-compute | ||
570 | a revocation certificate corresponding to your ego. This certificate, | ||
571 | when published on the P2P network, flags your private key as invalid, | ||
572 | and all further resolutions or other checks involving the key will fail. | ||
573 | |||
574 | A revocation certificate is thus a useful tool when things go out of | ||
575 | control, but at the same time it should be stored securely. | ||
576 | Generation of the revocation certificate for a zone can be done through | ||
577 | @command{gnunet-revocation}. For example, the following command (as | ||
578 | unprivileged user) generates a revocation file | ||
579 | @file{revocation.dat} for the zone @code{zone1}: | ||
580 | @command{gnunet-revocation -f revocation.dat -R zone1} | ||
581 | |||
582 | The above command only pre-computes a revocation certificate. It does | ||
583 | not revoke the given zone. Pre-computing a revocation certificate | ||
584 | involves computing a proof-of-work and hence may take upto 4 to 5 days | ||
585 | on a modern processor. Note that you can abort and resume the | ||
586 | calculation at any time. Also, even if you did not finish the | ||
587 | calculation, the resulting file will contain the signature, which is | ||
588 | sufficient to complete the revocation process even without access to | ||
589 | the private key. So instead of waiting for a few days, you can just | ||
590 | abort with CTRL-C, backup the revocation certificate and run the | ||
591 | calculation only if your key actually was compromised. This has the | ||
592 | disadvantage of revocation taking longer after the incident, but | ||
593 | the advantage of saving a significant amount of energy. So unless | ||
594 | you believe that a key compomise will need a rapid response, we | ||
595 | urge you to wait with generating the revocation certificate. | ||
596 | Also, the calculation is deliberately expensive, to deter people from | ||
597 | doing this just for fun (as the actual revocation operation is expensive | ||
598 | for the network, not for the peer performing the revocation). | ||
599 | |||
600 | To avoid TL;DR ones from accidentally revocating their zones, I am not | ||
601 | giving away the command, but its simple: the actual revocation is | ||
602 | performed by using the @command{-p} option | ||
603 | of @command{gnunet-revocation}. | ||
604 | |||
605 | |||
606 | |||
607 | @node What's Next? | ||
608 | @subsection What's Next? | ||
609 | @c %**end of header | ||
610 | |||
611 | This may seem not like much of an application yet, but you have | ||
612 | just been one of the first to perform a decentralized secure name | ||
613 | lookup (where nobody could have altered the value supplied by your | ||
614 | friend) in a privacy-preserving manner (your query on the network | ||
615 | and the corresponding response were always encrypted). So what | ||
616 | can you really do with this? Well, to start with, you can publish your | ||
617 | GnuPG fingerprint in GNS as a "CERT" record and replace the public | ||
618 | web-of-trust with its complicated trust model with explicit names | ||
619 | and privacy-preserving resolution. Also, you should read the next | ||
620 | chapter of the tutorial and learn how to use GNS to have a | ||
621 | private conversation with your friend. Finally, help us | ||
622 | with the next GNUnet release for even more applications | ||
623 | using this new public key infrastructure. | ||
624 | |||
625 | @node First steps - Using GNUnet Conversation | ||
626 | @section First steps - Using GNUnet Conversation | ||
627 | @c %**end of header | ||
628 | |||
629 | Before starting the tutorial, you should be aware that | ||
630 | @code{gnunet-conversation} is currently only available | ||
631 | as an interactive shell tool and that the call quality | ||
632 | tends to be abysmal. There are also some awkward | ||
633 | steps necessary to use it. The developers are aware | ||
634 | of this and will work hard to address these issues | ||
635 | in the near future. | ||
636 | |||
637 | |||
638 | @menu | ||
639 | * Testing your Audio Equipment:: | ||
640 | * GNS Zones:: | ||
641 | * Future Directions:: | ||
642 | @end menu | ||
643 | |||
644 | @node Testing your Audio Equipment | ||
645 | @subsection Testing your Audio Equipment | ||
646 | @c %**end of header | ||
647 | |||
648 | First, you should use @code{gnunet-conversation-test} to check that your | ||
649 | microphone and speaker are working correctly. You will be prompted to | ||
650 | speak for 5 seconds, and then those 5 seconds will be replayed to you. | ||
651 | The network is not involved in this test. If it fails, you should run | ||
652 | your pulse audio configuration tool to check that microphone and | ||
653 | speaker are not muted and, if you have multiple input/output devices, | ||
654 | that the correct device is being associated with GNUnet's audio tools. | ||
655 | |||
656 | @node GNS Zones | ||
657 | @subsection GNS Zones | ||
658 | @c %**end of header | ||
659 | |||
660 | @code{gnunet-conversation} uses GNS for addressing. This means that | ||
661 | you need to have a GNS zone created before using it. Information | ||
662 | about how to create GNS zones can be found here. | ||
663 | |||
664 | |||
665 | @menu | ||
666 | * Picking an Identity:: | ||
667 | * Calling somebody:: | ||
668 | @end menu | ||
669 | |||
670 | @node Picking an Identity | ||
671 | @subsubsection Picking an Identity | ||
672 | @c %**end of header | ||
673 | |||
674 | To make a call with @code{gnunet-conversation}, you first | ||
675 | need to choose an identity. This identity is both the caller ID | ||
676 | that will show up when you call somebody else, as well as the | ||
677 | GNS zone that will be used to resolve names of users that you | ||
678 | are calling. Usually, the @code{master-zone} is a reasonable | ||
679 | choice. Run | ||
680 | |||
681 | @example | ||
682 | gnunet-conversation -e master-zone | ||
683 | @end example | ||
684 | |||
685 | @noindent | ||
686 | to start the command-line tool. You will see a message saying | ||
687 | that your phone is now "active on line 0". You can connect | ||
688 | multiple phones on different lines at the same peer. For the | ||
689 | first phone, the line zero is of course a fine choice. | ||
690 | |||
691 | Next, you should type in @command{/help} for a list of | ||
692 | available commands. We will explain the important ones | ||
693 | during this tutorial. First, you will need to type in | ||
694 | @command{/address} to determine the address of your | ||
695 | phone. The result should look something like this: | ||
696 | |||
697 | @example | ||
698 | /address | ||
699 | 0-PD67SGHF3E0447TU9HADIVU9OM7V4QHTOG0EBU69TFRI2LG63DR0 | ||
700 | @end example | ||
701 | |||
702 | @noindent | ||
703 | Here, the "0" is your phone line, and what follows | ||
704 | after the hyphen is your peer's identity. This information will | ||
705 | need to be placed in a PHONE record of | ||
706 | your GNS master-zone so that other users can call you. | ||
707 | |||
708 | Start @code{gnunet-namestore-gtk} now (possibly from another | ||
709 | shell) and create an entry home-phone in your master zone. | ||
710 | For the record type, select PHONE. You should then see the | ||
711 | PHONE dialog: | ||
712 | |||
713 | @c image here | ||
714 | |||
715 | Note: Do not choose the expiry time to be 'Never'. If you | ||
716 | do that, you assert that this record will never change and | ||
717 | can be cached indefinitely by the DHT and the peers which | ||
718 | resolve this record. A reasonable period is 1 year. | ||
719 | |||
720 | Enter your peer identity under Peer and leave the line | ||
721 | at zero. Select the first option to make the record public. | ||
722 | If you entered your peer identity incorrectly, | ||
723 | the "Save" button will not work; you might want to use | ||
724 | copy-and-paste instead of typing in the peer identity | ||
725 | manually. Save the record. | ||
726 | |||
727 | @node Calling somebody | ||
728 | @subsubsection Calling somebody | ||
729 | @c %**end of header | ||
730 | |||
731 | Now you can call a buddy. Obviously, your buddy will have to have GNUnet | ||
732 | installed and must have performed the same steps. Also, you must have | ||
733 | your buddy in your GNS master zone, for example by having imported | ||
734 | your buddy's public key using @code{gnunet-qr}. Suppose your buddy | ||
735 | is in your zone as @code{buddy.gnu} and they also created their | ||
736 | phone using a label "home-phone". Then you can initiate a call using: | ||
737 | |||
738 | @example | ||
739 | /call home-phone.buddy.gnu | ||
740 | @end example | ||
741 | |||
742 | It may take some time for GNUnet to resolve the name and to establish | ||
743 | a link. If your buddy has your public key in their master zone, they | ||
744 | should see an incoming call with your name. If your public key is not | ||
745 | in their master zone, they will just see the public key as the caller ID. | ||
746 | |||
747 | Your buddy then can answer the call using the "/accept" command. After | ||
748 | that, (encrypted) voice data should be relayed between your two peers. | ||
749 | Either of you can end the call using @command{/cancel}. You can exit | ||
750 | @code{gnunet-converation} using @command{/quit}. | ||
751 | |||
752 | @node Future Directions | ||
753 | @subsection Future Directions | ||
754 | @c %**end of header | ||
755 | |||
756 | Note that we do not envision people to use gnunet-conversation like this | ||
757 | forever. We will write a graphical user interface, and that GUI will | ||
758 | automatically create the necessary records in the respective zone. | ||
759 | |||
760 | @node First steps - Using the GNUnet VPN | ||
761 | @section First steps - Using the GNUnet VPN | ||
762 | @c %**end of header | ||
763 | |||
764 | |||
765 | @menu | ||
766 | * VPN Preliminaries:: | ||
767 | * Exit configuration:: | ||
768 | * GNS configuration:: | ||
769 | * Accessing the service:: | ||
770 | * Using a Browser:: | ||
771 | @end menu | ||
772 | |||
773 | @node VPN Preliminaries | ||
774 | @subsection VPN Preliminaries | ||
775 | @c %**end of header | ||
776 | |||
777 | To test the GNUnet VPN, we should first run a web server. | ||
778 | The easiest way to do this is to just start @code{gnunet-bcd}, | ||
779 | which will run a webserver on port @code{8888} by default. | ||
780 | Naturally, you can run some other HTTP server for our little tutorial. | ||
781 | |||
782 | If you have not done this, you should also configure your | ||
783 | Name System Service switch to use GNS. In your @code{/etc/nsswitch.conf} | ||
784 | you should fine a line like this: | ||
785 | |||
786 | @example | ||
787 | hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4 | ||
788 | @end example | ||
789 | |||
790 | @noindent | ||
791 | The exact details may differ a bit, which is fine. Add the text | ||
792 | @code{gns [NOTFOUND=return]} after @code{files}: | ||
793 | |||
794 | @example | ||
795 | hosts: files gns [NOTFOUND=return] mdns4_minimal [NOTFOUND=return] dns mdns4 | ||
796 | @end example | ||
797 | |||
798 | @noindent | ||
799 | You might want to make sure that @code{/lib/libnss_gns.so.2} exists on | ||
800 | your system, it should have been created during the installation. | ||
801 | If not, re-run | ||
802 | |||
803 | @example | ||
804 | $ configure --with-nssdir=/lib | ||
805 | $ cd src/gns/nss; sudo make install | ||
806 | @end example | ||
807 | |||
808 | @noindent | ||
809 | to install the NSS plugins in the proper location. | ||
810 | |||
811 | @node Exit configuration | ||
812 | @subsection Exit configuration | ||
813 | @c %**end of header | ||
814 | |||
815 | Stop your peer (as user @code{gnunet}, run @command{gnunet-arm -e}) and | ||
816 | run @command{gnunet-setup}. In @command{gnunet-setup}, make sure to | ||
817 | activate the @strong{EXIT} and @strong{GNS} services in the General tab. | ||
818 | Then select the Exit tab. Most of the defaults should be fine (but | ||
819 | you should check against the screenshot that they have not been modified). | ||
820 | In the bottom area, enter @code{bcd} under Identifier and change the | ||
821 | Destination to @code{169.254.86.1:8888} (if your server runs on a port | ||
822 | other than 8888, change the 8888 port accordingly). | ||
823 | |||
824 | Now exit @command{gnunet-setup} and restart your peer | ||
825 | (@command{gnunet-arm -s}). | ||
826 | |||
827 | @node GNS configuration | ||
828 | @subsection GNS configuration | ||
829 | @c %**end of header | ||
830 | |||
831 | Now, using your normal user (not the @code{gnunet} system user), run | ||
832 | @command{gnunet-gtk}. Select the GNS icon and add a new label www in your | ||
833 | master zone. For the record type, select @code{VPN}. You should then | ||
834 | see the VPN dialog: | ||
835 | |||
836 | @c insert image | ||
837 | |||
838 | Under peer, you need to supply the peer identity of your own peer. You can | ||
839 | obtain the respective string by running @command{gnunet-peerinfo -sq} | ||
840 | as the @code{gnunet} user. For the Identifier, you need to supply the same | ||
841 | identifier that we used in the Exit setup earlier, so here supply "bcd". | ||
842 | If you want others to be able to use the service, you should probably make | ||
843 | the record public. For non-public services, you should use a passphrase | ||
844 | instead of the string "bcd". Save the record and | ||
845 | exit @command{gnunet-gtk}. | ||
846 | |||
847 | @node Accessing the service | ||
848 | @subsection Accessing the service | ||
849 | @c %**end of header | ||
850 | |||
851 | You should now be able to access your webserver. Type in: | ||
852 | |||
853 | @example | ||
854 | $ wget http://www.gnu/ | ||
855 | @end example | ||
856 | |||
857 | @noindent | ||
858 | The request will resolve to the VPN record, telling the GNS resolver | ||
859 | to route it via the GNUnet VPN. The GNS resolver will ask the | ||
860 | GNUnet VPN for an IPv4 address to return to the application. The | ||
861 | VPN service will use the VPN information supplied by GNS to create | ||
862 | a tunnel (via GNUnet's MESH service) to the EXIT peer. | ||
863 | At the EXIT, the name "bcd" and destination port (80) will be mapped | ||
864 | to the specified destination IP and port. While all this is currently | ||
865 | happening on just the local machine, it should also work with other | ||
866 | peers --- naturally, they will need a way to access your GNS zone | ||
867 | first, for example by learning your public key from a QR code on | ||
868 | your business card. | ||
869 | |||
870 | @node Using a Browser | ||
871 | @subsection Using a Browser | ||
872 | @c %**end of header | ||
873 | |||
874 | Sadly, modern browsers tend to bypass the Name Services Switch and | ||
875 | attempt DNS resolution directly. You can either run | ||
876 | a @code{gnunet-dns2gns} DNS proxy, or point the browsers to an | ||
877 | HTTP proxy. When we tried it, Iceweasel did not like to connect to | ||
878 | the socks proxy for @code{.gnu} TLDs, even if we disabled its | ||
879 | autoblunder of changing @code{.gnu} to ".gnu.com". Still, | ||
880 | using the HTTP proxy with Chrome does work. | ||
881 | |||
882 | @node File-sharing | ||
883 | @section File-sharing | ||
884 | @c %**end of header | ||
885 | |||
886 | This chapter documents the GNUnet file-sharing application. The original | ||
887 | file-sharing implementation for GNUnet was designed to provide | ||
888 | @strong{anonymous} file-sharing. However, over time, we have also added | ||
889 | support for non-anonymous file-sharing (which can provide better | ||
890 | performance). Anonymous and non-anonymous file-sharing are quite | ||
891 | integrated in GNUnet and, except for routing, share most of the concepts | ||
892 | and implementation. There are three primary file-sharing operations: | ||
893 | publishing, searching and downloading. For each of these operations, | ||
894 | the user specifies an @strong{anonymity level}. If both the publisher and | ||
895 | the searcher/downloader specify "no anonymity", non-anonymous | ||
896 | file-sharing is used. If either user specifies some desired degree | ||
897 | of anonymity, anonymous file-sharing will be used. | ||
898 | |||
899 | In this chapter, we will first look at the various concepts in GNUnet's | ||
900 | file-sharing implementation. Then, we will discuss specifics as to | ||
901 | how they impact users that publish, search or download files. | ||
902 | |||
903 | |||
904 | |||
905 | @menu | ||
906 | * File-sharing Concepts:: | ||
907 | * File-sharing Publishing:: | ||
908 | * File-sharing Searching:: | ||
909 | * File-sharing Downloading:: | ||
910 | * File-sharing Directories:: | ||
911 | * File-sharing Namespace Management:: | ||
912 | * File-Sharing URIs:: | ||
913 | @end menu | ||
914 | |||
915 | @node File-sharing Concepts | ||
916 | @subsection File-sharing Concepts | ||
917 | @c %**end of header | ||
918 | |||
919 | Sharing files in GNUnet is not quite as simple as in traditional | ||
920 | file sharing systems. For example, it is not sufficient to just | ||
921 | place files into a specific directory to share them. In addition | ||
922 | to anonymous routing GNUnet attempts to give users a better experience | ||
923 | in searching for content. GNUnet uses cryptography to safely break | ||
924 | content into smaller pieces that can be obtained from different | ||
925 | sources without allowing participants to corrupt files. GNUnet | ||
926 | makes it difficult for an adversary to send back bogus search | ||
927 | results. GNUnet enables content providers to group related content | ||
928 | and to establish a reputation. Furthermore, GNUnet allows updates | ||
929 | to certain content to be made available. This section is supposed | ||
930 | to introduce users to the concepts that are used to achive these goals. | ||
931 | |||
932 | |||
933 | @menu | ||
934 | * Files:: | ||
935 | * Keywords:: | ||
936 | * Directories:: | ||
937 | * Pseudonyms:: | ||
938 | * Namespaces:: | ||
939 | * Advertisements:: | ||
940 | * Anonymity level:: | ||
941 | * Content Priority:: | ||
942 | * Replication:: | ||
943 | @end menu | ||
944 | |||
945 | @node Files | ||
946 | @subsubsection Files | ||
947 | @c %**end of header | ||
948 | |||
949 | A file in GNUnet is just a sequence of bytes. Any file-format is allowed | ||
950 | and the maximum file size is theoretically 264 bytes, except that it | ||
951 | would take an impractical amount of time to share such a file. | ||
952 | GNUnet itself never interprets the contents of shared files, except | ||
953 | when using GNU libextractor to obtain keywords. | ||
954 | |||
955 | @node Keywords | ||
956 | @subsubsection Keywords | ||
957 | @c %**end of header | ||
958 | |||
959 | Keywords are the most simple mechanism to find files on GNUnet. | ||
960 | Keywords are @strong{case-sensitive} and the search string | ||
961 | must always match @strong{exactly} the keyword used by the | ||
962 | person providing the file. Keywords are never transmitted in | ||
963 | plaintext. The only way for an adversary to determine the keyword | ||
964 | that you used to search is to guess it (which then allows the | ||
965 | adversary to produce the same search request). Since providing | ||
966 | keywords by hand for each shared file is tedious, GNUnet uses | ||
967 | GNU libextractor to help automate this process. Starting a | ||
968 | keyword search on a slow machine can take a little while since | ||
969 | the keyword search involves computing a fresh RSA key to formulate the | ||
970 | request. | ||
971 | |||
972 | @node Directories | ||
973 | @subsubsection Directories | ||
974 | @c %**end of header | ||
975 | |||
976 | A directory in GNUnet is a list of file identifiers with meta data. | ||
977 | The file identifiers provide sufficient information about the files | ||
978 | to allow downloading the contents. Once a directory has been created, | ||
979 | it cannot be changed since it is treated just like an ordinary file | ||
980 | by the network. Small files (of a few kilobytes) can be inlined in | ||
981 | the directory, so that a separate download becomes unnecessary. | ||
982 | |||
983 | @node Pseudonyms | ||
984 | @subsubsection Pseudonyms | ||
985 | @c %**end of header | ||
986 | |||
987 | Pseudonyms in GNUnet are essentially public-private (RSA) key pairs | ||
988 | that allow a GNUnet user to maintain an identity (which may or may not | ||
989 | be detached from their real-life identity). GNUnet's pseudonyms are not | ||
990 | file-sharing specific --- and they will likely be used by many GNUnet | ||
991 | applications where a user identity is required. | ||
992 | |||
993 | Note that a pseudonym is NOT bound to a GNUnet peer. There can be multiple | ||
994 | pseudonyms for a single user, and users could (theoretically) share the | ||
995 | private pseudonym keys (currently only out-of-band by knowing which files | ||
996 | to copy around). | ||
997 | |||
998 | @node Namespaces | ||
999 | @subsubsection Namespaces | ||
1000 | @c %**end of header | ||
1001 | |||
1002 | A namespace is a set of files that were signed by the same pseudonym. | ||
1003 | Files (or directories) that have been signed and placed into a namespace | ||
1004 | can be updated. Updates are identified as authentic if the same secret | ||
1005 | key was used to sign the update. Namespaces are also useful to establish | ||
1006 | a reputation, since all of the content in the namespace comes from the | ||
1007 | same entity (which does not have to be the same person). | ||
1008 | |||
1009 | @node Advertisements | ||
1010 | @subsubsection Advertisements | ||
1011 | @c %**end of header | ||
1012 | |||
1013 | Advertisements are used to notify other users about the existence of a | ||
1014 | namespace. Advertisements are propagated using the normal keyword search. | ||
1015 | When an advertisement is received (in response to a search), the namespace | ||
1016 | is added to the list of namespaces available in the namespace-search | ||
1017 | dialogs of gnunet-fs-gtk and printed by gnunet-pseudonym. Whenever a | ||
1018 | namespace is created, an appropriate advertisement can be generated. | ||
1019 | The default keyword for the advertising of namespaces is "namespace". | ||
1020 | |||
1021 | Note that GNUnet differenciates between your pseudonyms (the identities | ||
1022 | that you control) and namespaces. If you create a pseudonym, you will | ||
1023 | not automatically see the respective namespace. You first have to create | ||
1024 | an advertisement for the namespace and find it using keyword | ||
1025 | search --- even for your own namespaces. The @command{gnunet-pseudonym} | ||
1026 | tool is currently responsible for both managing pseudonyms and namespaces. | ||
1027 | This will likely change in the future to reduce the potential for | ||
1028 | confusion. | ||
1029 | |||
1030 | @node Anonymity level | ||
1031 | @subsubsection Anonymity level | ||
1032 | @c %**end of header | ||
1033 | |||
1034 | The anonymity level determines how hard it should be for an adversary to | ||
1035 | determine the identity of the publisher or the searcher/downloader. An | ||
1036 | anonymity level of zero means that anonymity is not required. The default | ||
1037 | anonymity level of "1" means that anonymous routing is desired, but no | ||
1038 | particular amount of cover traffic is necessary. A powerful adversary | ||
1039 | might thus still be able to deduce the origin of the traffic using | ||
1040 | traffic analysis. Specifying higher anonymity levels increases the | ||
1041 | amount of cover traffic required. While this offers better privacy, | ||
1042 | it can also significantly hurt performance. | ||
1043 | |||
1044 | @node Content Priority | ||
1045 | @subsubsection Content Priority | ||
1046 | @c %**end of header | ||
1047 | |||
1048 | Depending on the peer's configuration, GNUnet peers migrate content | ||
1049 | between peers. Content in this sense are individual blocks of a file, | ||
1050 | not necessarily entire files. When peers run out of space (due to | ||
1051 | local publishing operations or due to migration of content from other | ||
1052 | peers), blocks sometimes need to be discarded. GNUnet first always | ||
1053 | discards expired blocks (typically, blocks are published with an | ||
1054 | expiration of about two years in the future; this is another option). | ||
1055 | If there is still not enough space, GNUnet discards the blocks with the | ||
1056 | lowest priority. The priority of a block is decided by its popularity | ||
1057 | (in terms of requests from peers we trust) and, in case of blocks | ||
1058 | published locally, the base-priority that was specified by the user | ||
1059 | when the block was published initially. | ||
1060 | |||
1061 | @node Replication | ||
1062 | @subsubsection Replication | ||
1063 | @c %**end of header | ||
1064 | |||
1065 | When peers migrate content to other systems, the replication level | ||
1066 | of a block is used to decide which blocks need to be migrated most | ||
1067 | urgently. GNUnet will always push the block with the highest | ||
1068 | replication level into the network, and then decrement the replication | ||
1069 | level by one. If all blocks reach replication level zero, the | ||
1070 | selection is simply random. | ||
1071 | |||
1072 | @node File-sharing Publishing | ||
1073 | @subsection File-sharing Publishing | ||
1074 | @c %**end of header | ||
1075 | |||
1076 | The command @command{gnunet-publish} can be used to add content | ||
1077 | to the network. The basic format of the command is | ||
1078 | |||
1079 | @example | ||
1080 | $ gnunet-publish [-n] [-k KEYWORDS]* [-m TYPE:VALUE] FILENAME | ||
1081 | @end example | ||
1082 | |||
1083 | |||
1084 | @menu | ||
1085 | * Important command-line options:: | ||
1086 | * Indexing vs. Inserting:: | ||
1087 | @end menu | ||
1088 | |||
1089 | @node Important command-line options | ||
1090 | @subsubsection Important command-line options | ||
1091 | @c %**end of header | ||
1092 | |||
1093 | The option -k is used to specify keywords for the file that | ||
1094 | should be inserted. You can supply any number of keywords, | ||
1095 | and each of the keywords will be sufficient to locate and | ||
1096 | retrieve the file. | ||
1097 | |||
1098 | The -m option is used to specify meta-data, such as descriptions. | ||
1099 | You can use -m multiple times. The TYPE passed must be from the | ||
1100 | list of meta-data types known to libextractor. You can obtain this | ||
1101 | list by running @command{extract -L}. Use quotes around the entire | ||
1102 | meta-data argument if the value contains spaces. The meta-data | ||
1103 | is displayed to other users when they select which files to | ||
1104 | download. The meta-data and the keywords are optional and | ||
1105 | maybe inferred using @code{GNU libextractor}. | ||
1106 | |||
1107 | gnunet-publish has a few additional options to handle namespaces and | ||
1108 | directories. See the man-page for details. | ||
1109 | |||
1110 | @node Indexing vs. Inserting | ||
1111 | @subsubsection Indexing vs Inserting | ||
1112 | @c %**end of header | ||
1113 | |||
1114 | By default, GNUnet indexes a file instead of making a full copy. | ||
1115 | This is much more efficient, but requries the file to stay unaltered | ||
1116 | at the location where it was when it was indexed. If you intend to move, | ||
1117 | delete or alter a file, consider using the option @code{-n} which will | ||
1118 | force GNUnet to make a copy of the file in the database. | ||
1119 | |||
1120 | Since it is much less efficient, this is strongly discouraged for large | ||
1121 | files. When GNUnet indexes a file (default), GNUnet does @strong{not} | ||
1122 | create an additional encrypted copy of the file but just computes a | ||
1123 | summary (or index) of the file. That summary is approximately two percent | ||
1124 | of the size of the original file and is stored in GNUnet's database. | ||
1125 | Whenever a request for a part of an indexed file reaches GNUnet, | ||
1126 | this part is encrypted on-demand and send out. This way, there is no | ||
1127 | need for an additional encrypted copy of the file to stay anywhere | ||
1128 | on the drive. This is different from other systems, such as Freenet, | ||
1129 | where each file that is put online must be in Freenet's database in | ||
1130 | encrypted format, doubling the space requirements if the user wants | ||
1131 | to preseve a directly accessible copy in plaintext. | ||
1132 | |||
1133 | Thus indexing should be used for all files where the user will keep | ||
1134 | using this file (at the location given to gnunet-publish) and does | ||
1135 | not want to retrieve it back from GNUnet each time. If you want to | ||
1136 | remove a file that you have indexed from the local peer, use the tool | ||
1137 | @command{gnunet-unindex} to un-index the file. | ||
1138 | |||
1139 | The option @code{-n} may be used if the user fears that the file might | ||
1140 | be found on their drive (assuming the computer comes under the control | ||
1141 | of an adversary). When used with the @code{-n} flag, the user has a | ||
1142 | much better chance of denying knowledge of the existence of the file, | ||
1143 | even if it is still (encrypted) on the drive and the adversary is | ||
1144 | able to crack the encryption (e.g. by guessing the keyword. | ||
1145 | |||
1146 | @node File-sharing Searching | ||
1147 | @subsection File-sharing Searching | ||
1148 | @c %**end of header | ||
1149 | |||
1150 | The command @command{gnunet-search} can be used to search | ||
1151 | for content on GNUnet. The format is: | ||
1152 | |||
1153 | @example | ||
1154 | $ gnunet-search [-t TIMEOUT] KEYWORD | ||
1155 | @end example | ||
1156 | |||
1157 | @noindent | ||
1158 | The -t option specifies that the query should timeout after | ||
1159 | approximately TIMEOUT seconds. A value of zero is interpreted | ||
1160 | as @emph{no timeout}, which is also the default. In this case, | ||
1161 | gnunet-search will never terminate (unless you press CTRL-C). | ||
1162 | |||
1163 | If multiple words are passed as keywords, they will all be | ||
1164 | considered optional. Prefix keywords with a "+" to make them mandatory. | ||
1165 | |||
1166 | Note that searching using | ||
1167 | |||
1168 | @example | ||
1169 | $ gnunet-search Das Kapital | ||
1170 | @end example | ||
1171 | |||
1172 | @noindent | ||
1173 | is not the same as searching for | ||
1174 | |||
1175 | @example | ||
1176 | $ gnunet-search "Das Kapital" | ||
1177 | @end example | ||
1178 | |||
1179 | @noindent | ||
1180 | as the first will match files shared under the keywords | ||
1181 | "Das" or "Kapital" whereas the second will match files | ||
1182 | shared under the keyword "Das Kapital". | ||
1183 | |||
1184 | Search results are printed by gnunet-search like this: | ||
1185 | |||
1186 | @example | ||
1187 | $ gnunet-download -o "COPYING" --- gnunet://fs/chk/N8...C92.17992 | ||
1188 | => The GNU Public License <= (mimetype: text/plain) | ||
1189 | @end example | ||
1190 | |||
1191 | @noindent | ||
1192 | The first line is the command you would have to enter to download | ||
1193 | the file. The argument passed to @code{-o} is the suggested | ||
1194 | filename (you may change it to whatever you like). | ||
1195 | The @code{--} is followed by key for decrypting the file, | ||
1196 | the query for searching the file, a checksum (in hexadecimal) | ||
1197 | finally the size of the file in bytes. | ||
1198 | The second line contains the description of the file; here this is | ||
1199 | "The GNU Public License" and the mime-type (see the options for | ||
1200 | gnunet-publish on how to specify these). | ||
1201 | |||
1202 | @node File-sharing Downloading | ||
1203 | @subsection File-sharing Downloading | ||
1204 | @c %**end of header | ||
1205 | |||
1206 | In order to download a file, you need the three values returned by | ||
1207 | @command{gnunet-search}. | ||
1208 | You can then use the tool @command{gnunet-download} to obtain the file: | ||
1209 | |||
1210 | @example | ||
1211 | $ gnunet-download -o FILENAME --- GNUNETURL | ||
1212 | @end example | ||
1213 | |||
1214 | @noindent | ||
1215 | FILENAME specifies the name of the file where GNUnet is supposed | ||
1216 | to write the result. Existing files are overwritten. If the | ||
1217 | existing file contains blocks that are identical to the | ||
1218 | desired download, those blocks will not be downloaded again | ||
1219 | (automatic resume). | ||
1220 | |||
1221 | If you want to download the GPL from the previous example, | ||
1222 | you do the following: | ||
1223 | |||
1224 | @example | ||
1225 | $ gnunet-download -o "COPYING" --- gnunet://fs/chk/N8...92.17992 | ||
1226 | @end example | ||
1227 | |||
1228 | @noindent | ||
1229 | If you ever have to abort a download, you can continue it at any time by | ||
1230 | re-issuing @command{gnunet-download} with the same filename. | ||
1231 | In that case, GNUnet will @strong{not} download blocks again that are | ||
1232 | already present. | ||
1233 | |||
1234 | GNUnet's file-encoding mechanism will ensure file integrity, even if the | ||
1235 | existing file was not downloaded from GNUnet in the first place. | ||
1236 | |||
1237 | You may want to use the @command{-V} switch (must be added before | ||
1238 | the @command{--}) to turn on verbose reporting. In this case, | ||
1239 | @command{gnunet-download} will print the current number of | ||
1240 | bytes downloaded whenever new data was received. | ||
1241 | |||
1242 | @node File-sharing Directories | ||
1243 | @subsection File-sharing Directories | ||
1244 | @c %**end of header | ||
1245 | |||
1246 | Directories are shared just like ordinary files. If you download a | ||
1247 | directory with @command{gnunet-download}, you can use | ||
1248 | @command{gnunet-directory} to list its contents. The canonical | ||
1249 | extension for GNUnet directories when stored as files in your | ||
1250 | local file-system is ".gnd". The contents of a directory are URIs and | ||
1251 | meta data. | ||
1252 | The URIs contain all the information required by | ||
1253 | @command{gnunet-download} to retrieve the file. The meta data | ||
1254 | typically includes the mime-type, description, a filename and | ||
1255 | other meta information, and possibly even the full original file | ||
1256 | (if it was small). | ||
1257 | |||
1258 | @node File-sharing Namespace Management | ||
1259 | @subsection File-sharing Namespace Management | ||
1260 | @c %**end of header | ||
1261 | |||
1262 | @b{Please note that the text in this subsection is outdated and needs} | ||
1263 | @b{to be rewritten for version 0.10!} | ||
1264 | |||
1265 | The gnunet-pseudonym tool can be used to create pseudonyms and | ||
1266 | to advertise namespaces. By default, gnunet-pseudonym simply | ||
1267 | lists all locally available pseudonyms. | ||
1268 | |||
1269 | |||
1270 | @menu | ||
1271 | * Creating Pseudonyms:: | ||
1272 | * Deleting Pseudonyms:: | ||
1273 | * Advertising namespaces:: | ||
1274 | * Namespace names:: | ||
1275 | * Namespace root:: | ||
1276 | @end menu | ||
1277 | |||
1278 | @node Creating Pseudonyms | ||
1279 | @subsubsection Creating Pseudonyms | ||
1280 | @c %**end of header | ||
1281 | |||
1282 | With the @command{-C NICK} option it can also be used to | ||
1283 | create a new pseudonym. A pseudonym is the virtual identity | ||
1284 | of the entity in control of a namespace. Anyone can create | ||
1285 | any number of pseudonyms. Note that creating a pseudonym can | ||
1286 | take a few minutes depending on the performance of the machine | ||
1287 | used. | ||
1288 | |||
1289 | @node Deleting Pseudonyms | ||
1290 | @subsubsection Deleting Pseudonyms | ||
1291 | @c %**end of header | ||
1292 | |||
1293 | With the @command{-D NICK} option pseudonyms can be deleted. | ||
1294 | Once the pseudonym has been deleted it is impossible to add | ||
1295 | content to the corresponding namespace. Deleting the | ||
1296 | pseudonym does not make the namespace or any content in it | ||
1297 | unavailable. | ||
1298 | |||
1299 | @node Advertising namespaces | ||
1300 | @subsubsection Advertising namespaces | ||
1301 | @c %**end of header | ||
1302 | |||
1303 | Each namespace is associated with meta-data that describes | ||
1304 | the namespace. This meta data is provided by the user at | ||
1305 | the time that the namespace is advertised. Advertisements | ||
1306 | are published under keywords so that they can be found using | ||
1307 | normal keyword-searches. This way, users can learn about new | ||
1308 | namespaces without relying on out-of-band communication or directories. | ||
1309 | A suggested keyword to use for all namespaces is simply "namespace". | ||
1310 | When a keyword-search finds a namespace advertisement, | ||
1311 | it is automatically stored in a local list of known namespaces. | ||
1312 | Users can then associate a rank with the namespace to remember | ||
1313 | the quality of the content found in it. | ||
1314 | |||
1315 | @node Namespace names | ||
1316 | @subsubsection Namespace names | ||
1317 | @c %**end of header | ||
1318 | |||
1319 | While the namespace is uniquely identified by its ID, another way | ||
1320 | to refer to the namespace is to use the NICKNAME. | ||
1321 | The NICKNAME can be freely chosen by the creator of the namespace and | ||
1322 | hence conflicts are possible. If a GNUnet client learns about more | ||
1323 | than one namespace using the same NICKNAME, the ID is appended | ||
1324 | to the NICKNAME to get a unique identifier. | ||
1325 | |||
1326 | @node Namespace root | ||
1327 | @subsubsection Namespace root | ||
1328 | @c %**end of header | ||
1329 | |||
1330 | An item of particular interest in the namespace advertisement is | ||
1331 | the ROOT. The ROOT is the identifier of a designated entry in the | ||
1332 | namespace. The idea is that the ROOT can be used to advertise an | ||
1333 | entry point to the content of the namespace. | ||
1334 | |||
1335 | @node File-Sharing URIs | ||
1336 | @subsection File-Sharing URIs | ||
1337 | @c %**end of header | ||
1338 | |||
1339 | GNUnet (currently) uses four different types of URIs for | ||
1340 | file-sharing. They all begin with "gnunet://fs/". | ||
1341 | This section describes the four different URI types in detail. | ||
1342 | |||
1343 | |||
1344 | @menu | ||
1345 | * Encoding of hash values in URIs:: | ||
1346 | * Content Hash Key (chk):: | ||
1347 | * Location identifiers (loc):: | ||
1348 | * Keyword queries (ksk):: | ||
1349 | * Namespace content (sks):: | ||
1350 | @end menu | ||
1351 | |||
1352 | @node Encoding of hash values in URIs | ||
1353 | @subsubsection Encoding of hash values in URIs | ||
1354 | @c %**end of header | ||
1355 | |||
1356 | Most URIs include some hash values. Hashes are encoded using | ||
1357 | base32hex (RFC 2938). | ||
1358 | |||
1359 | @node Content Hash Key (chk) | ||
1360 | @subsubsection Content Hash Key (chk) | ||
1361 | @c %**end of header | ||
1362 | |||
1363 | A chk-URI is used to (uniquely) identify a file or directory | ||
1364 | and to allow peers to download the file. Files are stored in | ||
1365 | GNUnet as a tree of encrypted blocks. | ||
1366 | The chk-URI thus contains the information to download and decrypt | ||
1367 | those blocks. A chk-URI has the format | ||
1368 | "gnunet://fs/chk/KEYHASH.QUERYHASH.SIZE". Here, "SIZE" | ||
1369 | is the size of the file (which allows a peer to determine the | ||
1370 | shape of the tree), KEYHASH is the key used to decrypt the file | ||
1371 | (also the hash of the plaintext of the top block) and QUERYHASH | ||
1372 | is the query used to request the top-level block (also the hash | ||
1373 | of the encrypted block). | ||
1374 | |||
1375 | @node Location identifiers (loc) | ||
1376 | @subsubsection Location identifiers (loc) | ||
1377 | @c %**end of header | ||
1378 | |||
1379 | For non-anonymous file-sharing, loc-URIs are used to specify which | ||
1380 | peer is offering the data (in addition to specifying all of the | ||
1381 | data from a chk-URI). Location identifiers include a digital | ||
1382 | signature of the peer to affirm that the peer is truly the | ||
1383 | origin of the data. The format is | ||
1384 | "gnunet://fs/loc/KEYHASH.QUERYHASH.SIZE.PEER.SIG.EXPTIME". | ||
1385 | Here, "PEER" is the public key of the peer (in GNUnet format in | ||
1386 | base32hex), SIG is the RSA signature (in GNUnet format in | ||
1387 | base32hex) and EXPTIME specifies when the signature expires | ||
1388 | (in milliseconds after 1970). | ||
1389 | |||
1390 | @node Keyword queries (ksk) | ||
1391 | @subsubsection Keyword queries (ksk) | ||
1392 | @c %**end of header | ||
1393 | |||
1394 | A keyword-URI is used to specify that the desired operation | ||
1395 | is the search using a particular keyword. The format is simply | ||
1396 | "gnunet://fs/ksk/KEYWORD". Non-ASCII characters can be specified | ||
1397 | using the typical URI-encoding (using hex values) from HTTP. | ||
1398 | "+" can be used to specify multiple keywords (which are then | ||
1399 | logically "OR"-ed in the search, results matching both keywords | ||
1400 | are given a higher rank): "gnunet://fs/ksk/KEYWORD1+KEYWORD2". | ||
1401 | |||
1402 | @node Namespace content (sks) | ||
1403 | @subsubsection Namespace content (sks) | ||
1404 | @c %**end of header | ||
1405 | |||
1406 | Namespaces are sets of files that have been approved by some (usually | ||
1407 | pseudonymous) user --- typically by that user publishing all of the | ||
1408 | files together. A file can be in many namespaces. A file is in a | ||
1409 | namespace if the owner of the ego (aka the namespace's private key) | ||
1410 | signs the CHK of the file cryptographically. An SKS-URI is used to | ||
1411 | search a namespace. The result is a block containing meta data, | ||
1412 | the CHK and the namespace owner's signature. The format of a sks-URI | ||
1413 | is "gnunet://fs/sks/NAMESPACE/IDENTIFIER". Here, "NAMESPACE" | ||
1414 | is the public key for the namespace. "IDENTIFIER" is a freely | ||
1415 | chosen keyword (or password!). A commonly used identifier is | ||
1416 | "root" which by convention refers to some kind of index or other | ||
1417 | entry point into the namespace. | ||
1418 | |||
1419 | @node The GNU Name System | ||
1420 | @section The GNU Name System | ||
1421 | @c %**end of header | ||
1422 | |||
1423 | |||
1424 | The GNU Name System (GNS) is secure and decentralized naming system. | ||
1425 | It allows its users to resolve and register names within the @code{.gnu} | ||
1426 | @dfn{top-level domain} (TLD). | ||
1427 | |||
1428 | GNS is designed to provide: | ||
1429 | @itemize @bullet | ||
1430 | @item Censorship resistance | ||
1431 | @item Query privacy | ||
1432 | @item Secure name resolution | ||
1433 | @item Compatibility with DNS | ||
1434 | @end itemize | ||
1435 | |||
1436 | For the initial configuration and population of your | ||
1437 | GNS installation, please follow the GNS setup instructions. | ||
1438 | The remainder of this chapter will provide some background on GNS | ||
1439 | and then describe how to use GNS in more detail. | ||
1440 | |||
1441 | Unlike DNS, GNS does not rely on central root zones or authorities. | ||
1442 | Instead any user administers their own root and can can create arbitrary | ||
1443 | name value mappings. Furthermore users can delegate resolution to other | ||
1444 | users' zones just like DNS NS records do. Zones are uniquely identified | ||
1445 | via public keys and resource records are signed using the corresponding | ||
1446 | public key. Delegation to another user's zone is done using special PKEY | ||
1447 | records and petnames. A petname is a name that can be freely chosen by | ||
1448 | the user. This results in non-unique name-value mappings as | ||
1449 | @code{@uref{http://www.bob.gnu/, www.bob.gnu}} to one user might be | ||
1450 | @code{@uref{http://www.friend.gnu/, www.friend.gnu}} for someone else. | ||
1451 | |||
1452 | |||
1453 | @menu | ||
1454 | * Maintaining your own Zones:: | ||
1455 | * Obtaining your Zone Key:: | ||
1456 | * Adding Links to Other Zones:: | ||
1457 | * The Three Local Zones of GNS:: | ||
1458 | * The Master Zone:: | ||
1459 | * The Private Zone:: | ||
1460 | * The Shorten Zone:: | ||
1461 | * The ZKEY Top Level Domain in GNS:: | ||
1462 | * Resource Records in GNS:: | ||
1463 | @end menu | ||
1464 | |||
1465 | |||
1466 | @node Maintaining your own Zones | ||
1467 | @subsection Maintaining your own Zones | ||
1468 | |||
1469 | To setup your GNS system you must execute: | ||
1470 | |||
1471 | @example | ||
1472 | $ gnunet-gns-import.sh | ||
1473 | @end example | ||
1474 | |||
1475 | @noindent | ||
1476 | This will boostrap your zones and create the necessary key material. | ||
1477 | Your keys can be listed using the @command{gnunet-identity} | ||
1478 | command line tool: | ||
1479 | |||
1480 | @example | ||
1481 | $ gnunet-identity -d | ||
1482 | @end example | ||
1483 | |||
1484 | @noindent | ||
1485 | You can arbitrarily create your own zones using the gnunet-identity | ||
1486 | tool using: | ||
1487 | |||
1488 | @example | ||
1489 | $ gnunet-identity -C "new_zone" | ||
1490 | @end example | ||
1491 | |||
1492 | @noindent | ||
1493 | Now you can add (or edit, or remove) records in your GNS zone using the | ||
1494 | gnunet-setup GUI or using the gnunet-namestore command-line tool. | ||
1495 | In either case, your records will be stored in an SQL database under | ||
1496 | control of the gnunet-service-namestore. Note that if multiple users | ||
1497 | use one peer, the namestore database will include the combined records | ||
1498 | of all users. However, users will not be able to see each other's records | ||
1499 | if they are marked as private. | ||
1500 | |||
1501 | To provide a simple example for editing your own zone, suppose you | ||
1502 | have your own web server with IP 1.2.3.4. Then you can put an | ||
1503 | A record (A records in DNS are for IPv4 IP addresses) into your | ||
1504 | local zone using the command: | ||
1505 | |||
1506 | @example | ||
1507 | $ gnunet-namestore -z master-zone -a -n www -t A -V 1.2.3.4 -e never | ||
1508 | @end example | ||
1509 | |||
1510 | @noindent | ||
1511 | Afterwards, you will be able to access your webpage under "www.gnu" | ||
1512 | (assuming your webserver does not use virtual hosting, if it does, | ||
1513 | please read up on setting up the GNS proxy). | ||
1514 | |||
1515 | Similar commands will work for other types of DNS and GNS records, | ||
1516 | the syntax largely depending on the type of the record. | ||
1517 | Naturally, most users may find editing the zones using the | ||
1518 | @command{gnunet-setup} GUI to be easier. | ||
1519 | |||
1520 | @node Obtaining your Zone Key | ||
1521 | @subsection Obtaining your Zone Key | ||
1522 | |||
1523 | Each zone in GNS has a public-private key. Usually, gnunet-namestore and | ||
1524 | gnunet-setup will access your private key as necessary, so you do not | ||
1525 | have to worry about those. What is important is your public key | ||
1526 | (or rather, the hash of your public key), as you will likely want to | ||
1527 | give it to others so that they can securely link to you. | ||
1528 | |||
1529 | You can usually get the hash of your public key using | ||
1530 | |||
1531 | @example | ||
1532 | $ gnunet-identity -d $options | grep master-zone | awk '@{print $3@}' | ||
1533 | @end example | ||
1534 | |||
1535 | @noindent | ||
1536 | For example, the output might be something like: | ||
1537 | |||
1538 | @example | ||
1539 | DC3SEECJORPHQNVRH965A6N74B1M37S721IG4RBQ15PJLLPJKUE0 | ||
1540 | @end example | ||
1541 | |||
1542 | @noindent | ||
1543 | Alternatively, you can obtain a QR code with your zone key AND | ||
1544 | your pseudonym from gnunet-gtk. The QR code is displayed in the | ||
1545 | GNS tab and can be stored to disk using the Save as button next | ||
1546 | to the image. | ||
1547 | |||
1548 | @node Adding Links to Other Zones | ||
1549 | @subsection Adding Links to Other Zones | ||
1550 | |||
1551 | |||
1552 | A central operation in GNS is the ability to securely delegate to | ||
1553 | other zones. Basically, by adding a delegation you make all of the | ||
1554 | names from the other zone available to yourself. This section | ||
1555 | describes how to create delegations. | ||
1556 | |||
1557 | Suppose you have a friend who you call 'bob' who also uses GNS. | ||
1558 | You can then delegate resolution of names to Bob's zone by adding | ||
1559 | a PKEY record to their local zone: | ||
1560 | |||
1561 | @example | ||
1562 | $ gnunet-namestore -a -n bob --type PKEY -V XXXX -e never | ||
1563 | @end example | ||
1564 | |||
1565 | @noindent | ||
1566 | Note that XXXX in the command above must be replaced with the | ||
1567 | hash of Bob's public key (the output your friend obtained using | ||
1568 | the gnunet-identity command from the previous section and told you, | ||
1569 | for example by giving you a business card containing this | ||
1570 | information as a QR code). | ||
1571 | |||
1572 | Assuming Bob has an A record for their website under the name of | ||
1573 | www in his zone, you can then access Bob's website under | ||
1574 | www.bob.gnu --- as well as any (public) GNS record that Bob has | ||
1575 | in their zone by replacing www with the respective name of the | ||
1576 | record in Bob's zone. | ||
1577 | |||
1578 | @c themselves? themself? | ||
1579 | Furthermore, if Bob has themselves a (public) delegation to Carol's | ||
1580 | zone under "carol", you can access Carol's records under | ||
1581 | NAME.carol.bob.gnu (where NAME is the name of Carol's record you | ||
1582 | want to access). | ||
1583 | |||
1584 | @node The Three Local Zones of GNS | ||
1585 | @subsection The Three Local Zones of GNS | ||
1586 | |||
1587 | Each user GNS has control over three zones. Each of the zones | ||
1588 | has a different purpose. These zones are the | ||
1589 | |||
1590 | @itemize @bullet | ||
1591 | |||
1592 | @item master zone, | ||
1593 | @item private zone, and the | ||
1594 | @item shorten zone. | ||
1595 | @end itemize | ||
1596 | |||
1597 | @node The Master Zone | ||
1598 | @subsection The Master Zone | ||
1599 | |||
1600 | |||
1601 | The master zone is your personal TLD. Names within the @code{.gnu} | ||
1602 | namespace are resolved relative to this zone. You can arbitrarily | ||
1603 | add records to this zone and selectively publish those records. | ||
1604 | |||
1605 | @node The Private Zone | ||
1606 | @subsection The Private Zone | ||
1607 | |||
1608 | |||
1609 | The private zone is a subzone (or subdomain in DNS terms) of your | ||
1610 | master zone. It should be used for records that you want to keep | ||
1611 | private. For example @code{bank.private.gnu}. The key idea is that | ||
1612 | you want to keep your private records separate, if just to know | ||
1613 | that those names are not available to other users. | ||
1614 | |||
1615 | @node The Shorten Zone | ||
1616 | @subsection The Shorten Zone | ||
1617 | |||
1618 | |||
1619 | The shorten zone can either be a subzone of the master zone or the | ||
1620 | private zone. It is different from the other zones in that GNS | ||
1621 | will automatically populate this zone with other users' zones based | ||
1622 | on their PSEU records whenever you resolve a name. | ||
1623 | |||
1624 | For example if you go to | ||
1625 | @code{@uref{http://www.bob.alice.dave.gnu/, www.bob.alice.dave.gnu}}, | ||
1626 | GNS will try to import @code{bob} into your shorten zone. Having | ||
1627 | obtained Bob's PKEY from @code{alice.dave.gnu}, GNS will lookup the | ||
1628 | PSEU record for @code{+} in Bob's zone. If it exists and the specified | ||
1629 | pseudonym is not taken, Bob's PKEY will be automatically added under | ||
1630 | that pseudonym (i.e. "bob") into your shorten zone. From then on, | ||
1631 | Bob's webpage will also be available for you as | ||
1632 | @code{@uref{http://www.bob.short.gnu/, www.bob.short.gnu}}. | ||
1633 | This feature is called @b{automatic name shortening} and is supposed to | ||
1634 | keep GNS names as short and memorable as possible. | ||
1635 | |||
1636 | @node The ZKEY Top Level Domain in GNS | ||
1637 | @subsection The ZKEY Top Level Domain in GNS | ||
1638 | |||
1639 | |||
1640 | GNS also provides a secure and globally unique namespace under the .zkey | ||
1641 | top-level domain. A name in the .zkey TLD corresponds to the (printable) | ||
1642 | public key of a zone. Names in the .zkey TLD are then resolved by querying | ||
1643 | the respective zone. The .zkey TLD is expected to be used under rare | ||
1644 | circumstances where globally unique names are required and for | ||
1645 | integration with legacy systems. | ||
1646 | |||
1647 | @node Resource Records in GNS | ||
1648 | @subsection Resource Records in GNS | ||
1649 | |||
1650 | |||
1651 | GNS supports the majority of the DNS records as defined in | ||
1652 | @uref{http://www.ietf.org/rfc/rfc1035.txt, RFC 1035}. Additionally, | ||
1653 | GNS defines some new record types the are unique to the GNS system. | ||
1654 | For example, GNS-specific resource records are used to give petnames | ||
1655 | for zone delegation, revoke zone keys and provide some compatibility | ||
1656 | features. | ||
1657 | |||
1658 | For some DNS records, GNS does extended processing to increase their | ||
1659 | usefulness in GNS. In particular, GNS introduces special names | ||
1660 | referred to as "zone relative names". Zone relative names are allowed | ||
1661 | in some resource record types (for example, in NS and CNAME records) | ||
1662 | and can also be used in links on webpages. Zone relative names end | ||
1663 | in ".+" which indicates that the name needs to be resolved relative | ||
1664 | to the current authoritative zone. The extended processing of those | ||
1665 | names will expand the ".+" with the correct delegation chain to the | ||
1666 | authoritative zone (replacing ".+" with the name of the location | ||
1667 | where the name was encountered) and hence generate a | ||
1668 | valid @code{.gnu} name. | ||
1669 | |||
1670 | GNS currently supports the following record types: | ||
1671 | |||
1672 | @menu | ||
1673 | * NICK:: | ||
1674 | * PKEY:: | ||
1675 | * BOX:: | ||
1676 | * LEHO:: | ||
1677 | * VPN:: | ||
1678 | * A AAAA and TXT:: | ||
1679 | * CNAME:: | ||
1680 | * GNS2DNS:: | ||
1681 | * SOA SRV PTR and MX:: | ||
1682 | @end menu | ||
1683 | |||
1684 | @node NICK | ||
1685 | @subsubsection NICK | ||
1686 | |||
1687 | A NICK record is used to give a zone a name. With a NICK record, you can | ||
1688 | essentially specify how you would like to be called. GNS expects this | ||
1689 | record under the name "+" in the zone's database (NAMESTORE); however, | ||
1690 | it will then automatically be copied into each record set, so that | ||
1691 | clients never need to do a separate lookup to discover the NICK record. | ||
1692 | |||
1693 | @b{Example}@ | ||
1694 | |||
1695 | @example | ||
1696 | Name: +; RRType: NICK; Value: bob | ||
1697 | @end example | ||
1698 | |||
1699 | @noindent | ||
1700 | This record in Bob's zone will tell other users that this zone wants | ||
1701 | to be referred to as 'bob'. Note that nobody is obliged to call Bob's | ||
1702 | zone 'bob' in their own zones. It can be seen as a | ||
1703 | recommendation ("Please call me 'bob'"). | ||
1704 | |||
1705 | @node PKEY | ||
1706 | @subsubsection PKEY | ||
1707 | |||
1708 | PKEY records are used to add delegation to other users' zones and | ||
1709 | give those zones a petname. | ||
1710 | |||
1711 | @b{Example}@ | ||
1712 | |||
1713 | Let Bob's zone be identified by the hash "ABC012". Bob is your friend | ||
1714 | so you want to give them the petname "friend". Then you add the | ||
1715 | following record to your zone: | ||
1716 | |||
1717 | @example | ||
1718 | Name: friend; RRType: PKEY; Value: ABC012; | ||
1719 | @end example | ||
1720 | |||
1721 | @noindent | ||
1722 | This will allow you to resolve records in bob's zone | ||
1723 | under "*.friend.gnu". | ||
1724 | |||
1725 | @node BOX | ||
1726 | @subsubsection BOX | ||
1727 | |||
1728 | BOX records are there to integrate information from TLSA or | ||
1729 | SRV records under the main label. In DNS, TLSA and SRV records | ||
1730 | use special names of the form @code{_port._proto.(label.)*tld} to | ||
1731 | indicate the port number and protocol (i.e. tcp or udp) for which | ||
1732 | the TLSA or SRV record is valid. This causes various problems, and | ||
1733 | is elegantly solved in GNS by integrating the protocol and port | ||
1734 | numbers together with the respective value into a "BOX" record. | ||
1735 | Note that in the GUI, you do not get to edit BOX records directly | ||
1736 | right now --- the GUI will provide the illusion of directly | ||
1737 | editing the TLSA and SRV records, even though they internally | ||
1738 | are BOXed up. | ||
1739 | |||
1740 | @node LEHO | ||
1741 | @subsubsection LEHO | ||
1742 | |||
1743 | The LEgacy HOstname of a server. Some webservers expect a specific | ||
1744 | hostname to provide a service (virtiual hosting). Also SSL | ||
1745 | certificates usually contain DNS names. To provide the expected | ||
1746 | legacy DNS name for a server, the LEHO record can be used. | ||
1747 | To mitigate the just mentioned issues the GNS proxy has to be used. | ||
1748 | The GNS proxy will use the LEHO information to apply the necessary | ||
1749 | transformations. | ||
1750 | |||
1751 | @node VPN | ||
1752 | @subsubsection VPN | ||
1753 | |||
1754 | GNS allows easy access to services provided by the GNUnet Virtual Public | ||
1755 | Network. When the GNS resolver encounters a VPN record it will contact | ||
1756 | the VPN service to try and allocate an IPv4/v6 address (if the queries | ||
1757 | record type is an IP address) that can be used to contact the service. | ||
1758 | |||
1759 | @b{Example}@ | ||
1760 | |||
1761 | I want to provide access to the VPN service "web.gnu." on port 80 on peer | ||
1762 | ABC012:@ | ||
1763 | Name: www; RRType: VPN; Value: 80 ABC012 web.gnu. | ||
1764 | |||
1765 | The peer ABC012 is configured to provide an exit point for the service | ||
1766 | "web.gnu." on port 80 to it's server running locally on port 8080 by | ||
1767 | having the following lines in the @file{gnunet.conf} configuration file: | ||
1768 | |||
1769 | @example | ||
1770 | [web.gnunet.] | ||
1771 | TCP_REDIRECTS = 80:localhost4:8080 | ||
1772 | @end example | ||
1773 | |||
1774 | @node A AAAA and TXT | ||
1775 | @subsubsection A AAAA and TXT | ||
1776 | |||
1777 | Those records work in exactly the same fashion as in traditional DNS. | ||
1778 | |||
1779 | @node CNAME | ||
1780 | @subsubsection CNAME | ||
1781 | |||
1782 | As specified in RFC 1035 whenever a CNAME is encountered the query | ||
1783 | needs to be restarted with the specified name. In GNS a CNAME | ||
1784 | can either be: | ||
1785 | |||
1786 | @itemize @bullet | ||
1787 | @item A zone relative name, | ||
1788 | @item A zkey name or | ||
1789 | @item A DNS name (in which case resolution will continue outside | ||
1790 | of GNS with the systems DNS resolver) | ||
1791 | @end itemize | ||
1792 | |||
1793 | @node GNS2DNS | ||
1794 | @subsubsection GNS2DNS | ||
1795 | |||
1796 | GNS can delegate authority to a legacy DNS zone. For this, the | ||
1797 | name of the DNS nameserver and the name of the DNS zone are | ||
1798 | specified in a GNS2DNS record. | ||
1799 | |||
1800 | @b{Example} | ||
1801 | |||
1802 | @example | ||
1803 | Name: pet; RRType: GNS2DNS; Value: gnunet.org@@a.ns.joker.com | ||
1804 | @end example | ||
1805 | |||
1806 | @noindent | ||
1807 | Any query to @code{pet.gnu} will then be delegated to the DNS server at | ||
1808 | @code{a.ns.joker.com}. For example, | ||
1809 | @code{@uref{http://www.pet.gnu/, www.pet.gnu}} will result in a DNS query | ||
1810 | for @code{@uref{http://www.gnunet.org/, www.gnunet.org}} to the server | ||
1811 | at @code{a.ns.joker.com}. Delegation to DNS via NS records in GNS can | ||
1812 | be useful if you do not want to start resolution in the DNS root zone | ||
1813 | (due to issues such as censorship or availability). | ||
1814 | |||
1815 | Note that you would typically want to use a relative name for the | ||
1816 | nameserver, i.e. | ||
1817 | |||
1818 | @example | ||
1819 | Name: pet; RRType: GNS2DNS; Value: gnunet.org@@ns-joker.+@ | ||
1820 | Name: ns-joker; RRType: A; Value: 184.172.157.218 | ||
1821 | @end example | ||
1822 | |||
1823 | @noindent | ||
1824 | This way, you can avoid involving the DNS hierarchy in the resolution of | ||
1825 | @code{a.ns.joker.com}. In the example above, the problem may not be | ||
1826 | obvious as the nameserver for "gnunet.org" is in the ".com" zone. | ||
1827 | However, imagine the nameserver was "ns.gnunet.org". In this case, | ||
1828 | delegating to "ns.gnunet.org" would mean that despite using GNS, | ||
1829 | censorship in the DNS ".org" zone would still be effective. | ||
1830 | |||
1831 | @node SOA SRV PTR and MX | ||
1832 | @subsubsection SOA SRV PTR and MX | ||
1833 | |||
1834 | The domain names in those records can, again, be either | ||
1835 | |||
1836 | @itemize @bullet | ||
1837 | @item A zone relative name, | ||
1838 | @item A zkey name or | ||
1839 | @item A DNS name | ||
1840 | @end itemize | ||
1841 | |||
1842 | The resolver will expand the zone relative name if possible. | ||
1843 | Note that when using MX records within GNS, the target mail | ||
1844 | server might still refuse to accept e-mails to the resulting | ||
1845 | domain as the name might not match. GNS-enabled mail clients | ||
1846 | should use the ZKEY zone as the destination hostname and | ||
1847 | GNS-enabled mail servers should be configured to accept | ||
1848 | e-mails to the ZKEY-zones of all local users. | ||
1849 | |||
1850 | @node Using the Virtual Public Network | ||
1851 | @section Using the Virtual Public Network | ||
1852 | |||
1853 | @menu | ||
1854 | * Setting up an Exit node:: | ||
1855 | * Fedora and the Firewall:: | ||
1856 | * Setting up VPN node for protocol translation and tunneling:: | ||
1857 | @end menu | ||
1858 | |||
1859 | Using the GNUnet Virtual Public Network (VPN) application you can | ||
1860 | tunnel IP traffic over GNUnet. Moreover, the VPN comes | ||
1861 | with built-in protocol translation and DNS-ALG support, enabling | ||
1862 | IPv4-to-IPv6 protocol translation (in both directions). | ||
1863 | This chapter documents how to use the GNUnet VPN. | ||
1864 | |||
1865 | The first thing to note about the GNUnet VPN is that it is a public | ||
1866 | network. All participating peers can participate and there is no | ||
1867 | secret key to control access. So unlike common virtual private | ||
1868 | networks, the GNUnet VPN is not useful as a means to provide a | ||
1869 | "private" network abstraction over the Internet. The GNUnet VPN | ||
1870 | is a virtual network in the sense that it is an overlay over the | ||
1871 | Internet, using its own routing mechanisms and can also use an | ||
1872 | internal addressing scheme. The GNUnet VPN is an Internet | ||
1873 | underlay --- TCP/IP applications run on top of it. | ||
1874 | |||
1875 | The VPN is currently only supported on GNU/Linux systems. | ||
1876 | Support for operating systems that support TUN (such as FreeBSD) | ||
1877 | should be easy to add (or might not even require any coding at | ||
1878 | all --- we just did not test this so far). Support for other | ||
1879 | operating systems would require re-writing the code to create virtual | ||
1880 | network interfaces and to intercept DNS requests. | ||
1881 | |||
1882 | The VPN does not provide good anonymity. While requests are routed | ||
1883 | over the GNUnet network, other peers can directly see the source | ||
1884 | and destination of each (encapsulated) IP packet. Finally, if you | ||
1885 | use the VPN to access Internet services, the peer sending the | ||
1886 | request to the Internet will be able to observe and even alter | ||
1887 | the IP traffic. We will discuss additional security implications | ||
1888 | of using the VPN later in this chapter. | ||
1889 | |||
1890 | @node Setting up an Exit node | ||
1891 | @subsection Setting up an Exit node | ||
1892 | |||
1893 | Any useful operation with the VPN requires the existence of an exit | ||
1894 | node in the GNUnet Peer-to-Peer network. Exit functionality can only | ||
1895 | be enabled on peers that have regular Internet access. If you want | ||
1896 | to play around with the VPN or support the network, we encourage | ||
1897 | you to setup exit nodes. This chapter documents how to setup an | ||
1898 | exit node. | ||
1899 | |||
1900 | There are four types of exit functions an exit node can provide, | ||
1901 | and using the GNUnet VPN to access the Internet will only work | ||
1902 | nicely if the first three types are provided somewhere in | ||
1903 | the network. The four exit functions are: | ||
1904 | |||
1905 | @itemize @bullet | ||
1906 | @item DNS: allow other peers to use your DNS resolver | ||
1907 | @item IPv4: allow other peers to access your IPv4 Internet connection | ||
1908 | @item IPv6: allow other peers to access your IPv6 Internet connection | ||
1909 | @item Local service: allow other peers to access a specific TCP or | ||
1910 | UDP service your peer is providing | ||
1911 | @end itemize | ||
1912 | |||
1913 | By enabling "exit" in gnunet-setup and checking the respective boxes | ||
1914 | in the "exit" tab, you can easily choose which of the above exit | ||
1915 | functions you want to support. | ||
1916 | |||
1917 | Note, however, that by supporting the first three functions you will | ||
1918 | allow arbitrary other GNUnet users to access the Internet via your | ||
1919 | system. This is somewhat similar to running a Tor exit node. The | ||
1920 | Torproject has a nice article about what to consider if you want | ||
1921 | to do this here. We believe that generally running a DNS exit node | ||
1922 | is completely harmless. | ||
1923 | |||
1924 | The exit node configuration does currently not allow you to restrict the | ||
1925 | Internet traffic that leaves your system. In particular, you cannot | ||
1926 | exclude SMTP traffic (or block port 25) or limit to HTTP traffic using | ||
1927 | the GNUnet configuration. However, you can use your host firewall to | ||
1928 | restrict outbound connections from the virtual tunnel interface. This | ||
1929 | is highly recommended. In the future, we plan to offer a wider range | ||
1930 | of configuration options for exit nodes. | ||
1931 | |||
1932 | Note that by running an exit node GNUnet will configure your kernel | ||
1933 | to perform IP-forwarding (for IPv6) and NAT (for IPv4) so that the | ||
1934 | traffic from the virtual interface can be routed to the Internet. | ||
1935 | In order to provide an IPv6-exit, you need to have a subnet routed | ||
1936 | to your host's external network interface and assign a subrange of | ||
1937 | that subnet to the GNUnet exit's TUN interface. | ||
1938 | |||
1939 | When running a local service, you should make sure that the local | ||
1940 | service is (also) bound to the IP address of your EXIT interface | ||
1941 | (i.e. 169.254.86.1). It will NOT work if your local service is | ||
1942 | just bound to loopback. You may also want to create a "VPN" record | ||
1943 | in your zone of the GNU Name System to make it easy for others to | ||
1944 | access your service via a name instead of just the full service | ||
1945 | descriptor. Note that the identifier you assign the service can | ||
1946 | serve as a passphrase or shared secret, clients connecting to the | ||
1947 | service must somehow learn the service's name. VPN records in the | ||
1948 | GNU Name System can make this easier. | ||
1949 | |||
1950 | @node Fedora and the Firewall | ||
1951 | @subsection Fedora and the Firewall | ||
1952 | |||
1953 | |||
1954 | When using an exit node on Fedora 15, the standard firewall can | ||
1955 | create trouble even when not really exiting the local system! | ||
1956 | For IPv4, the standard rules seem fine. However, for IPv6 the | ||
1957 | standard rules prohibit traffic from the network range of the | ||
1958 | virtual interface created by the exit daemon to the local IPv6 | ||
1959 | address of the same interface (which is essentially loopback | ||
1960 | traffic, so you might suspect that a standard firewall would | ||
1961 | leave this traffic alone). However, as somehow for IPv6 the | ||
1962 | traffic is not recognized as originating from the local | ||
1963 | system (and as the connection is not already "established"), | ||
1964 | the firewall drops the traffic. You should still get ICMPv6 | ||
1965 | packets back, but that's obviously not very useful. | ||
1966 | |||
1967 | Possible ways to fix this include disabling the firewall (do you | ||
1968 | have a good reason for having it on?) or disabling the firewall | ||
1969 | at least for the GNUnet exit interface (or the respective | ||
1970 | IPv4/IPv6 address range). The best way to diagnose these kinds | ||
1971 | of problems in general involves setting the firewall to REJECT | ||
1972 | instead of DROP and to watch the traffic using wireshark | ||
1973 | (or tcpdump) to see if ICMP messages are generated when running | ||
1974 | some tests that should work. | ||
1975 | |||
1976 | @node Setting up VPN node for protocol translation and tunneling | ||
1977 | @subsection Setting up VPN node for protocol translation and tunneling | ||
1978 | |||
1979 | |||
1980 | The GNUnet VPN/PT subsystem enables you to tunnel IP traffic over the | ||
1981 | VPN to an exit node, from where it can then be forwarded to the | ||
1982 | Internet. This section documents how to setup VPN/PT on a node. | ||
1983 | Note that you can enable both the VPN and an exit on the same peer. | ||
1984 | In this case, IP traffic from your system may enter your peer's VPN | ||
1985 | and leave your peer's exit. This can be useful as a means to do | ||
1986 | protocol translation. For example, you might have an application that | ||
1987 | supports only IPv4 but needs to access an IPv6-only site. In this case, | ||
1988 | GNUnet would perform 4to6 protocol translation between the VPN (IPv4) | ||
1989 | and the Exit (IPv6). Similarly, 6to4 protocol translation is also | ||
1990 | possible. However, the primary use for GNUnet would be to access | ||
1991 | an Internet service running with an IP version that is not supported | ||
1992 | by your ISP. In this case, your IP traffic would be routed via GNUnet | ||
1993 | to a peer that has access to the Internet with the desired IP version. | ||
1994 | |||
1995 | Setting up an entry node into the GNUnet VPN primarily requires you | ||
1996 | to enable the "VPN/PT" option in "gnunet-setup". This will launch the | ||
1997 | "gnunet-service-vpn", "gnunet-service-dns" and "gnunet-daemon-pt" | ||
1998 | processes. The "gnunet-service-vpn" will create a virtual interface | ||
1999 | which will be used as the target for your IP traffic that enters the | ||
2000 | VPN. Additionally, a second virtual interface will be created by | ||
2001 | the "gnunet-service-dns" for your DNS traffic. You will then need to | ||
2002 | specify which traffic you want to tunnel over GNUnet. If your ISP only | ||
2003 | provides you with IPv4 or IPv6-access, you may choose to tunnel the | ||
2004 | other IP protocol over the GNUnet VPN. If you do not have an ISP | ||
2005 | (and are connected to other GNUnet peers via WLAN), you can also | ||
2006 | choose to tunnel all IP traffic over GNUnet. This might also provide | ||
2007 | you with some anonymity. After you enable the respective options | ||
2008 | and restart your peer, your Internet traffic should be tunneled | ||
2009 | over the GNUnet VPN. | ||
2010 | |||
2011 | The GNUnet VPN uses DNS-ALG to hijack your IP traffic. Whenever an | ||
2012 | application resolves a hostname (i.e. 'gnunet.org'), the | ||
2013 | "gnunet-daemon-pt" will instruct the "gnunet-service-dns" to intercept | ||
2014 | the request (possibly route it over GNUnet as well) and replace the | ||
2015 | normal answer with an IP in the range of the VPN's interface. | ||
2016 | "gnunet-daemon-pt" will then tell "gnunet-service-vpn" to forward all | ||
2017 | traffic it receives on the TUN interface via the VPN to the original | ||
2018 | destination. | ||
2019 | |||
2020 | For applications that do not use DNS, you can also manually create | ||
2021 | such a mapping using the gnunet-vpn command-line tool. Here, you | ||
2022 | specfiy the desired address family of the result (i.e. "-4"), and the | ||
2023 | intended target IP on the Internet ("-i 131.159.74.67") and | ||
2024 | "gnunet-vpn" will tell you which IP address in the range of your | ||
2025 | VPN tunnel was mapped. | ||
2026 | |||
2027 | @command{gnunet-vpn} can also be used to access "internal" services | ||
2028 | offered by GNUnet nodes. So if you happen to know a peer and a | ||
2029 | service offered by that peer, you can create an IP tunnel to | ||
2030 | that peer by specifying the peer's identity, service name and | ||
2031 | protocol (--tcp or --udp) and you will again receive an IP address | ||
2032 | that will terminate at the respective peer's service. | ||
diff --git a/doc/documentation/chapters/vocabulary.texi b/doc/documentation/chapters/vocabulary.texi new file mode 100644 index 000000000..85b40b17b --- /dev/null +++ b/doc/documentation/chapters/vocabulary.texi | |||
@@ -0,0 +1,72 @@ | |||
1 | @node Vocabulary | ||
2 | @chapter Vocabulary | ||
3 | |||
4 | @menu | ||
5 | * Definitions abbreviations and acronyms:: | ||
6 | * Words and characters:: | ||
7 | * Technical Assumptions:: | ||
8 | @end menu | ||
9 | |||
10 | Throughout this Reference Manual we will use certain words and characters | ||
11 | which are listed in this introductionary chapter. | ||
12 | |||
13 | @node Definitions abbreviations and acronyms | ||
14 | @section Definitions abbreviations and acronyms | ||
15 | |||
16 | @menu | ||
17 | * Definitions:: | ||
18 | @end menu | ||
19 | |||
20 | @node Definitions | ||
21 | @subsection Defitions | ||
22 | |||
23 | Throughout this Reference Manual, the following terms and definitions | ||
24 | apply. | ||
25 | |||
26 | @node Words and characters | ||
27 | @section Words and characters | ||
28 | |||
29 | @enumerate | ||
30 | @item | ||
31 | In chapter Installation Handbook, | ||
32 | ``@command{#}'' in example code blocks describes commands executed as root | ||
33 | |||
34 | @example | ||
35 | # echo "I am root" | ||
36 | I am root | ||
37 | @end example | ||
38 | |||
39 | @item | ||
40 | However, in the chapter GNUnet C Tutorial | ||
41 | ``@command{#}'' in example code blocks describes commands, ie comments. | ||
42 | |||
43 | @example | ||
44 | # Do the foobar thing: | ||
45 | $ make foobar | ||
46 | @end example | ||
47 | |||
48 | @item | ||
49 | Dollarsign ``@command{$}'' in example code blocks describes commands you | ||
50 | execute as unprivileged users. | ||
51 | |||
52 | @example | ||
53 | $ cd foo; ./configure --example-switch | ||
54 | @end example | ||
55 | |||
56 | @item | ||
57 | Backslash ``@command{\}'' describes linebreaks. | ||
58 | |||
59 | @example | ||
60 | ./configure --foo --bar --baz \ | ||
61 | --short-loop | ||
62 | @end example | ||
63 | |||
64 | ...expands to @code{./configure --foo --bar --baz --short-loop} | ||
65 | |||
66 | @end enumerate | ||
67 | |||
68 | @node Technical Assumptions | ||
69 | @section Technical Assumptions | ||
70 | |||
71 | @c Is it really assuming Bash (ie Bash extensions of POSIX being used)? | ||
72 | The shell on GNU systems is assumed to be Bash. | ||
diff --git a/doc/documentation/docstyle.css b/doc/documentation/docstyle.css new file mode 100644 index 000000000..8719248d0 --- /dev/null +++ b/doc/documentation/docstyle.css | |||
@@ -0,0 +1,76 @@ | |||
1 | html, body { | ||
2 | font-size: 1em; | ||
3 | text-align: left; | ||
4 | text-decoration: none; | ||
5 | } | ||
6 | html { background-color: #e7e7e7; } | ||
7 | |||
8 | body { | ||
9 | max-width: 74.92em; | ||
10 | margin: 0 auto; | ||
11 | padding: .5em 1em 1em 1em; | ||
12 | background-color: white; | ||
13 | border: .1em solid #c0c0c0; | ||
14 | } | ||
15 | |||
16 | h1, h2, h3, h4 { color: #333; } | ||
17 | h5, h6, dt { color: #222; } | ||
18 | |||
19 | |||
20 | a h3 { | ||
21 | color: #005090; | ||
22 | } | ||
23 | |||
24 | a[href] { color: #005090; } | ||
25 | a[href]:visited { color: #100070; } | ||
26 | a[href]:active, a[href]:hover { | ||
27 | color: #100070; | ||
28 | text-decoration: none; | ||
29 | } | ||
30 | |||
31 | .linkrow { | ||
32 | margin: 3em 0; | ||
33 | } | ||
34 | |||
35 | .linkrow { | ||
36 | text-align: center; | ||
37 | } | ||
38 | |||
39 | div.example { padding: .8em 1.2em .4em; } | ||
40 | pre.example { padding: .8em 1.2em; } | ||
41 | div.example, pre.example { | ||
42 | margin: 1em 0 1em 3% ; | ||
43 | -webkit-border-radius: .3em; | ||
44 | -moz-border-radius: .3em; | ||
45 | border-radius: .3em; | ||
46 | border: 1px solid #d4cbb6; | ||
47 | background-color: #f2efe4; | ||
48 | } | ||
49 | div.example > pre.example { | ||
50 | padding: 0 0 .4em; | ||
51 | margin: 0; | ||
52 | border: none; | ||
53 | } | ||
54 | |||
55 | |||
56 | /* This makes the very long tables of contents in Gnulib and other | ||
57 | manuals easier to read. */ | ||
58 | .contents ul, .shortcontents ul { font-weight: bold; } | ||
59 | .contents ul ul, .shortcontents ul ul { font-weight: normal; } | ||
60 | .contents ul { list-style: none; } | ||
61 | |||
62 | /* For colored navigation bars (Emacs manual): make the bar extend | ||
63 | across the whole width of the page and give it a decent height. */ | ||
64 | .header, .node { margin: 0 -1em; padding: 0 1em; } | ||
65 | .header p, .node p { line-height: 2em; } | ||
66 | |||
67 | /* For navigation links */ | ||
68 | .node a, .header a { display: inline-block; line-height: 2em; } | ||
69 | .node a:hover, .header a:hover { background: #f2efe4; } | ||
70 | |||
71 | table.cartouche { | ||
72 | border-collapse: collapse; | ||
73 | border-color: darkred; | ||
74 | border-style: solid; | ||
75 | border-width: 3px; | ||
76 | } | ||
diff --git a/doc/documentation/fdl-1.3.texi b/doc/documentation/fdl-1.3.texi new file mode 100644 index 000000000..cb71f05a1 --- /dev/null +++ b/doc/documentation/fdl-1.3.texi | |||
@@ -0,0 +1,505 @@ | |||
1 | @c The GNU Free Documentation License. | ||
2 | @center Version 1.3, 3 November 2008 | ||
3 | |||
4 | @c This file is intended to be included within another document, | ||
5 | @c hence no sectioning command or @node. | ||
6 | |||
7 | @display | ||
8 | Copyright @copyright{} 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. | ||
9 | @uref{http://fsf.org/} | ||
10 | |||
11 | Everyone is permitted to copy and distribute verbatim copies | ||
12 | of this license document, but changing it is not allowed. | ||
13 | @end display | ||
14 | |||
15 | @enumerate 0 | ||
16 | @item | ||
17 | PREAMBLE | ||
18 | |||
19 | The purpose of this License is to make a manual, textbook, or other | ||
20 | functional and useful document @dfn{free} in the sense of freedom: to | ||
21 | assure everyone the effective freedom to copy and redistribute it, | ||
22 | with or without modifying it, either commercially or noncommercially. | ||
23 | Secondarily, this License preserves for the author and publisher a way | ||
24 | to get credit for their work, while not being considered responsible | ||
25 | for modifications made by others. | ||
26 | |||
27 | This License is a kind of ``copyleft'', which means that derivative | ||
28 | works of the document must themselves be free in the same sense. It | ||
29 | complements the GNU General Public License, which is a copyleft | ||
30 | license designed for free software. | ||
31 | |||
32 | We have designed this License in order to use it for manuals for free | ||
33 | software, because free software needs free documentation: a free | ||
34 | program should come with manuals providing the same freedoms that the | ||
35 | software does. But this License is not limited to software manuals; | ||
36 | it can be used for any textual work, regardless of subject matter or | ||
37 | whether it is published as a printed book. We recommend this License | ||
38 | principally for works whose purpose is instruction or reference. | ||
39 | |||
40 | @item | ||
41 | APPLICABILITY AND DEFINITIONS | ||
42 | |||
43 | This License applies to any manual or other work, in any medium, that | ||
44 | contains a notice placed by the copyright holder saying it can be | ||
45 | distributed under the terms of this License. Such a notice grants a | ||
46 | world-wide, royalty-free license, unlimited in duration, to use that | ||
47 | work under the conditions stated herein. The ``Document'', below, | ||
48 | refers to any such manual or work. Any member of the public is a | ||
49 | licensee, and is addressed as ``you''. You accept the license if you | ||
50 | copy, modify or distribute the work in a way requiring permission | ||
51 | under copyright law. | ||
52 | |||
53 | A ``Modified Version'' of the Document means any work containing the | ||
54 | Document or a portion of it, either copied verbatim, or with | ||
55 | modifications and/or translated into another language. | ||
56 | |||
57 | A ``Secondary Section'' is a named appendix or a front-matter section | ||
58 | of the Document that deals exclusively with the relationship of the | ||
59 | publishers or authors of the Document to the Document's overall | ||
60 | subject (or to related matters) and contains nothing that could fall | ||
61 | directly within that overall subject. (Thus, if the Document is in | ||
62 | part a textbook of mathematics, a Secondary Section may not explain | ||
63 | any mathematics.) The relationship could be a matter of historical | ||
64 | connection with the subject or with related matters, or of legal, | ||
65 | commercial, philosophical, ethical or political position regarding | ||
66 | them. | ||
67 | |||
68 | The ``Invariant Sections'' are certain Secondary Sections whose titles | ||
69 | are designated, as being those of Invariant Sections, in the notice | ||
70 | that says that the Document is released under this License. If a | ||
71 | section does not fit the above definition of Secondary then it is not | ||
72 | allowed to be designated as Invariant. The Document may contain zero | ||
73 | Invariant Sections. If the Document does not identify any Invariant | ||
74 | Sections then there are none. | ||
75 | |||
76 | The ``Cover Texts'' are certain short passages of text that are listed, | ||
77 | as Front-Cover Texts or Back-Cover Texts, in the notice that says that | ||
78 | the Document is released under this License. A Front-Cover Text may | ||
79 | be at most 5 words, and a Back-Cover Text may be at most 25 words. | ||
80 | |||
81 | A ``Transparent'' copy of the Document means a machine-readable copy, | ||
82 | represented in a format whose specification is available to the | ||
83 | general public, that is suitable for revising the document | ||
84 | straightforwardly with generic text editors or (for images composed of | ||
85 | pixels) generic paint programs or (for drawings) some widely available | ||
86 | drawing editor, and that is suitable for input to text formatters or | ||
87 | for automatic translation to a variety of formats suitable for input | ||
88 | to text formatters. A copy made in an otherwise Transparent file | ||
89 | format whose markup, or absence of markup, has been arranged to thwart | ||
90 | or discourage subsequent modification by readers is not Transparent. | ||
91 | An image format is not Transparent if used for any substantial amount | ||
92 | of text. A copy that is not ``Transparent'' is called ``Opaque''. | ||
93 | |||
94 | Examples of suitable formats for Transparent copies include plain | ||
95 | ASCII without markup, Texinfo input format, La@TeX{} input | ||
96 | format, SGML or XML using a publicly available | ||
97 | DTD, and standard-conforming simple HTML, | ||
98 | PostScript or PDF designed for human modification. Examples | ||
99 | of transparent image formats include PNG, XCF and | ||
100 | JPG. Opaque formats include proprietary formats that can be | ||
101 | read and edited only by proprietary word processors, SGML or | ||
102 | XML for which the DTD and/or processing tools are | ||
103 | not generally available, and the machine-generated HTML, | ||
104 | PostScript or PDF produced by some word processors for | ||
105 | output purposes only. | ||
106 | |||
107 | The ``Title Page'' means, for a printed book, the title page itself, | ||
108 | plus such following pages as are needed to hold, legibly, the material | ||
109 | this License requires to appear in the title page. For works in | ||
110 | formats which do not have any title page as such, ``Title Page'' means | ||
111 | the text near the most prominent appearance of the work's title, | ||
112 | preceding the beginning of the body of the text. | ||
113 | |||
114 | The ``publisher'' means any person or entity that distributes copies | ||
115 | of the Document to the public. | ||
116 | |||
117 | A section ``Entitled XYZ'' means a named subunit of the Document whose | ||
118 | title either is precisely XYZ or contains XYZ in parentheses following | ||
119 | text that translates XYZ in another language. (Here XYZ stands for a | ||
120 | specific section name mentioned below, such as ``Acknowledgements'', | ||
121 | ``Dedications'', ``Endorsements'', or ``History''.) To ``Preserve the Title'' | ||
122 | of such a section when you modify the Document means that it remains a | ||
123 | section ``Entitled XYZ'' according to this definition. | ||
124 | |||
125 | The Document may include Warranty Disclaimers next to the notice which | ||
126 | states that this License applies to the Document. These Warranty | ||
127 | Disclaimers are considered to be included by reference in this | ||
128 | License, but only as regards disclaiming warranties: any other | ||
129 | implication that these Warranty Disclaimers may have is void and has | ||
130 | no effect on the meaning of this License. | ||
131 | |||
132 | @item | ||
133 | VERBATIM COPYING | ||
134 | |||
135 | You may copy and distribute the Document in any medium, either | ||
136 | commercially or noncommercially, provided that this License, the | ||
137 | copyright notices, and the license notice saying this License applies | ||
138 | to the Document are reproduced in all copies, and that you add no other | ||
139 | conditions whatsoever to those of this License. You may not use | ||
140 | technical measures to obstruct or control the reading or further | ||
141 | copying of the copies you make or distribute. However, you may accept | ||
142 | compensation in exchange for copies. If you distribute a large enough | ||
143 | number of copies you must also follow the conditions in section 3. | ||
144 | |||
145 | You may also lend copies, under the same conditions stated above, and | ||
146 | you may publicly display copies. | ||
147 | |||
148 | @item | ||
149 | COPYING IN QUANTITY | ||
150 | |||
151 | If you publish printed copies (or copies in media that commonly have | ||
152 | printed covers) of the Document, numbering more than 100, and the | ||
153 | Document's license notice requires Cover Texts, you must enclose the | ||
154 | copies in covers that carry, clearly and legibly, all these Cover | ||
155 | Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on | ||
156 | the back cover. Both covers must also clearly and legibly identify | ||
157 | you as the publisher of these copies. The front cover must present | ||
158 | the full title with all words of the title equally prominent and | ||
159 | visible. You may add other material on the covers in addition. | ||
160 | Copying with changes limited to the covers, as long as they preserve | ||
161 | the title of the Document and satisfy these conditions, can be treated | ||
162 | as verbatim copying in other respects. | ||
163 | |||
164 | If the required texts for either cover are too voluminous to fit | ||
165 | legibly, you should put the first ones listed (as many as fit | ||
166 | reasonably) on the actual cover, and continue the rest onto adjacent | ||
167 | pages. | ||
168 | |||
169 | If you publish or distribute Opaque copies of the Document numbering | ||
170 | more than 100, you must either include a machine-readable Transparent | ||
171 | copy along with each Opaque copy, or state in or with each Opaque copy | ||
172 | a computer-network location from which the general network-using | ||
173 | public has access to download using public-standard network protocols | ||
174 | a complete Transparent copy of the Document, free of added material. | ||
175 | If you use the latter option, you must take reasonably prudent steps, | ||
176 | when you begin distribution of Opaque copies in quantity, to ensure | ||
177 | that this Transparent copy will remain thus accessible at the stated | ||
178 | location until at least one year after the last time you distribute an | ||
179 | Opaque copy (directly or through your agents or retailers) of that | ||
180 | edition to the public. | ||
181 | |||
182 | It is requested, but not required, that you contact the authors of the | ||
183 | Document well before redistributing any large number of copies, to give | ||
184 | them a chance to provide you with an updated version of the Document. | ||
185 | |||
186 | @item | ||
187 | MODIFICATIONS | ||
188 | |||
189 | You may copy and distribute a Modified Version of the Document under | ||
190 | the conditions of sections 2 and 3 above, provided that you release | ||
191 | the Modified Version under precisely this License, with the Modified | ||
192 | Version filling the role of the Document, thus licensing distribution | ||
193 | and modification of the Modified Version to whoever possesses a copy | ||
194 | of it. In addition, you must do these things in the Modified Version: | ||
195 | |||
196 | @enumerate A | ||
197 | @item | ||
198 | Use in the Title Page (and on the covers, if any) a title distinct | ||
199 | from that of the Document, and from those of previous versions | ||
200 | (which should, if there were any, be listed in the History section | ||
201 | of the Document). You may use the same title as a previous version | ||
202 | if the original publisher of that version gives permission. | ||
203 | |||
204 | @item | ||
205 | List on the Title Page, as authors, one or more persons or entities | ||
206 | responsible for authorship of the modifications in the Modified | ||
207 | Version, together with at least five of the principal authors of the | ||
208 | Document (all of its principal authors, if it has fewer than five), | ||
209 | unless they release you from this requirement. | ||
210 | |||
211 | @item | ||
212 | State on the Title page the name of the publisher of the | ||
213 | Modified Version, as the publisher. | ||
214 | |||
215 | @item | ||
216 | Preserve all the copyright notices of the Document. | ||
217 | |||
218 | @item | ||
219 | Add an appropriate copyright notice for your modifications | ||
220 | adjacent to the other copyright notices. | ||
221 | |||
222 | @item | ||
223 | Include, immediately after the copyright notices, a license notice | ||
224 | giving the public permission to use the Modified Version under the | ||
225 | terms of this License, in the form shown in the Addendum below. | ||
226 | |||
227 | @item | ||
228 | Preserve in that license notice the full lists of Invariant Sections | ||
229 | and required Cover Texts given in the Document's license notice. | ||
230 | |||
231 | @item | ||
232 | Include an unaltered copy of this License. | ||
233 | |||
234 | @item | ||
235 | Preserve the section Entitled ``History'', Preserve its Title, and add | ||
236 | to it an item stating at least the title, year, new authors, and | ||
237 | publisher of the Modified Version as given on the Title Page. If | ||
238 | there is no section Entitled ``History'' in the Document, create one | ||
239 | stating the title, year, authors, and publisher of the Document as | ||
240 | given on its Title Page, then add an item describing the Modified | ||
241 | Version as stated in the previous sentence. | ||
242 | |||
243 | @item | ||
244 | Preserve the network location, if any, given in the Document for | ||
245 | public access to a Transparent copy of the Document, and likewise | ||
246 | the network locations given in the Document for previous versions | ||
247 | it was based on. These may be placed in the ``History'' section. | ||
248 | You may omit a network location for a work that was published at | ||
249 | least four years before the Document itself, or if the original | ||
250 | publisher of the version it refers to gives permission. | ||
251 | |||
252 | @item | ||
253 | For any section Entitled ``Acknowledgements'' or ``Dedications'', Preserve | ||
254 | the Title of the section, and preserve in the section all the | ||
255 | substance and tone of each of the contributor acknowledgements and/or | ||
256 | dedications given therein. | ||
257 | |||
258 | @item | ||
259 | Preserve all the Invariant Sections of the Document, | ||
260 | unaltered in their text and in their titles. Section numbers | ||
261 | or the equivalent are not considered part of the section titles. | ||
262 | |||
263 | @item | ||
264 | Delete any section Entitled ``Endorsements''. Such a section | ||
265 | may not be included in the Modified Version. | ||
266 | |||
267 | @item | ||
268 | Do not retitle any existing section to be Entitled ``Endorsements'' or | ||
269 | to conflict in title with any Invariant Section. | ||
270 | |||
271 | @item | ||
272 | Preserve any Warranty Disclaimers. | ||
273 | @end enumerate | ||
274 | |||
275 | If the Modified Version includes new front-matter sections or | ||
276 | appendices that qualify as Secondary Sections and contain no material | ||
277 | copied from the Document, you may at your option designate some or all | ||
278 | of these sections as invariant. To do this, add their titles to the | ||
279 | list of Invariant Sections in the Modified Version's license notice. | ||
280 | These titles must be distinct from any other section titles. | ||
281 | |||
282 | You may add a section Entitled ``Endorsements'', provided it contains | ||
283 | nothing but endorsements of your Modified Version by various | ||
284 | parties---for example, statements of peer review or that the text has | ||
285 | been approved by an organization as the authoritative definition of a | ||
286 | standard. | ||
287 | |||
288 | You may add a passage of up to five words as a Front-Cover Text, and a | ||
289 | passage of up to 25 words as a Back-Cover Text, to the end of the list | ||
290 | of Cover Texts in the Modified Version. Only one passage of | ||
291 | Front-Cover Text and one of Back-Cover Text may be added by (or | ||
292 | through arrangements made by) any one entity. If the Document already | ||
293 | includes a cover text for the same cover, previously added by you or | ||
294 | by arrangement made by the same entity you are acting on behalf of, | ||
295 | you may not add another; but you may replace the old one, on explicit | ||
296 | permission from the previous publisher that added the old one. | ||
297 | |||
298 | The author(s) and publisher(s) of the Document do not by this License | ||
299 | give permission to use their names for publicity for or to assert or | ||
300 | imply endorsement of any Modified Version. | ||
301 | |||
302 | @item | ||
303 | COMBINING DOCUMENTS | ||
304 | |||
305 | You may combine the Document with other documents released under this | ||
306 | License, under the terms defined in section 4 above for modified | ||
307 | versions, provided that you include in the combination all of the | ||
308 | Invariant Sections of all of the original documents, unmodified, and | ||
309 | list them all as Invariant Sections of your combined work in its | ||
310 | license notice, and that you preserve all their Warranty Disclaimers. | ||
311 | |||
312 | The combined work need only contain one copy of this License, and | ||
313 | multiple identical Invariant Sections may be replaced with a single | ||
314 | copy. If there are multiple Invariant Sections with the same name but | ||
315 | different contents, make the title of each such section unique by | ||
316 | adding at the end of it, in parentheses, the name of the original | ||
317 | author or publisher of that section if known, or else a unique number. | ||
318 | Make the same adjustment to the section titles in the list of | ||
319 | Invariant Sections in the license notice of the combined work. | ||
320 | |||
321 | In the combination, you must combine any sections Entitled ``History'' | ||
322 | in the various original documents, forming one section Entitled | ||
323 | ``History''; likewise combine any sections Entitled ``Acknowledgements'', | ||
324 | and any sections Entitled ``Dedications''. You must delete all | ||
325 | sections Entitled ``Endorsements.'' | ||
326 | |||
327 | @item | ||
328 | COLLECTIONS OF DOCUMENTS | ||
329 | |||
330 | You may make a collection consisting of the Document and other documents | ||
331 | released under this License, and replace the individual copies of this | ||
332 | License in the various documents with a single copy that is included in | ||
333 | the collection, provided that you follow the rules of this License for | ||
334 | verbatim copying of each of the documents in all other respects. | ||
335 | |||
336 | You may extract a single document from such a collection, and distribute | ||
337 | it individually under this License, provided you insert a copy of this | ||
338 | License into the extracted document, and follow this License in all | ||
339 | other respects regarding verbatim copying of that document. | ||
340 | |||
341 | @item | ||
342 | AGGREGATION WITH INDEPENDENT WORKS | ||
343 | |||
344 | A compilation of the Document or its derivatives with other separate | ||
345 | and independent documents or works, in or on a volume of a storage or | ||
346 | distribution medium, is called an ``aggregate'' if the copyright | ||
347 | resulting from the compilation is not used to limit the legal rights | ||
348 | of the compilation's users beyond what the individual works permit. | ||
349 | When the Document is included in an aggregate, this License does not | ||
350 | apply to the other works in the aggregate which are not themselves | ||
351 | derivative works of the Document. | ||
352 | |||
353 | If the Cover Text requirement of section 3 is applicable to these | ||
354 | copies of the Document, then if the Document is less than one half of | ||
355 | the entire aggregate, the Document's Cover Texts may be placed on | ||
356 | covers that bracket the Document within the aggregate, or the | ||
357 | electronic equivalent of covers if the Document is in electronic form. | ||
358 | Otherwise they must appear on printed covers that bracket the whole | ||
359 | aggregate. | ||
360 | |||
361 | @item | ||
362 | TRANSLATION | ||
363 | |||
364 | Translation is considered a kind of modification, so you may | ||
365 | distribute translations of the Document under the terms of section 4. | ||
366 | Replacing Invariant Sections with translations requires special | ||
367 | permission from their copyright holders, but you may include | ||
368 | translations of some or all Invariant Sections in addition to the | ||
369 | original versions of these Invariant Sections. You may include a | ||
370 | translation of this License, and all the license notices in the | ||
371 | Document, and any Warranty Disclaimers, provided that you also include | ||
372 | the original English version of this License and the original versions | ||
373 | of those notices and disclaimers. In case of a disagreement between | ||
374 | the translation and the original version of this License or a notice | ||
375 | or disclaimer, the original version will prevail. | ||
376 | |||
377 | If a section in the Document is Entitled ``Acknowledgements'', | ||
378 | ``Dedications'', or ``History'', the requirement (section 4) to Preserve | ||
379 | its Title (section 1) will typically require changing the actual | ||
380 | title. | ||
381 | |||
382 | @item | ||
383 | TERMINATION | ||
384 | |||
385 | You may not copy, modify, sublicense, or distribute the Document | ||
386 | except as expressly provided under this License. Any attempt | ||
387 | otherwise to copy, modify, sublicense, or distribute it is void, and | ||
388 | will automatically terminate your rights under this License. | ||
389 | |||
390 | However, if you cease all violation of this License, then your license | ||
391 | from a particular copyright holder is reinstated (a) provisionally, | ||
392 | unless and until the copyright holder explicitly and finally | ||
393 | terminates your license, and (b) permanently, if the copyright holder | ||
394 | fails to notify you of the violation by some reasonable means prior to | ||
395 | 60 days after the cessation. | ||
396 | |||
397 | Moreover, your license from a particular copyright holder is | ||
398 | reinstated permanently if the copyright holder notifies you of the | ||
399 | violation by some reasonable means, this is the first time you have | ||
400 | received notice of violation of this License (for any work) from that | ||
401 | copyright holder, and you cure the violation prior to 30 days after | ||
402 | your receipt of the notice. | ||
403 | |||
404 | Termination of your rights under this section does not terminate the | ||
405 | licenses of parties who have received copies or rights from you under | ||
406 | this License. If your rights have been terminated and not permanently | ||
407 | reinstated, receipt of a copy of some or all of the same material does | ||
408 | not give you any rights to use it. | ||
409 | |||
410 | @item | ||
411 | FUTURE REVISIONS OF THIS LICENSE | ||
412 | |||
413 | The Free Software Foundation may publish new, revised versions | ||
414 | of the GNU Free Documentation License from time to time. Such new | ||
415 | versions will be similar in spirit to the present version, but may | ||
416 | differ in detail to address new problems or concerns. See | ||
417 | @uref{http://www.gnu.org/copyleft/}. | ||
418 | |||
419 | Each version of the License is given a distinguishing version number. | ||
420 | If the Document specifies that a particular numbered version of this | ||
421 | License ``or any later version'' applies to it, you have the option of | ||
422 | following the terms and conditions either of that specified version or | ||
423 | of any later version that has been published (not as a draft) by the | ||
424 | Free Software Foundation. If the Document does not specify a version | ||
425 | number of this License, you may choose any version ever published (not | ||
426 | as a draft) by the Free Software Foundation. If the Document | ||
427 | specifies that a proxy can decide which future versions of this | ||
428 | License can be used, that proxy's public statement of acceptance of a | ||
429 | version permanently authorizes you to choose that version for the | ||
430 | Document. | ||
431 | |||
432 | @item | ||
433 | RELICENSING | ||
434 | |||
435 | ``Massive Multiauthor Collaboration Site'' (or ``MMC Site'') means any | ||
436 | World Wide Web server that publishes copyrightable works and also | ||
437 | provides prominent facilities for anybody to edit those works. A | ||
438 | public wiki that anybody can edit is an example of such a server. A | ||
439 | ``Massive Multiauthor Collaboration'' (or ``MMC'') contained in the | ||
440 | site means any set of copyrightable works thus published on the MMC | ||
441 | site. | ||
442 | |||
443 | ``CC-BY-SA'' means the Creative Commons Attribution-Share Alike 3.0 | ||
444 | license published by Creative Commons Corporation, a not-for-profit | ||
445 | corporation with a principal place of business in San Francisco, | ||
446 | California, as well as future copyleft versions of that license | ||
447 | published by that same organization. | ||
448 | |||
449 | ``Incorporate'' means to publish or republish a Document, in whole or | ||
450 | in part, as part of another Document. | ||
451 | |||
452 | An MMC is ``eligible for relicensing'' if it is licensed under this | ||
453 | License, and if all works that were first published under this License | ||
454 | somewhere other than this MMC, and subsequently incorporated in whole | ||
455 | or in part into the MMC, (1) had no cover texts or invariant sections, | ||
456 | and (2) were thus incorporated prior to November 1, 2008. | ||
457 | |||
458 | The operator of an MMC Site may republish an MMC contained in the site | ||
459 | under CC-BY-SA on the same site at any time before August 1, 2009, | ||
460 | provided the MMC is eligible for relicensing. | ||
461 | |||
462 | @end enumerate | ||
463 | |||
464 | @page | ||
465 | @heading ADDENDUM: How to use this License for your documents | ||
466 | |||
467 | To use this License in a document you have written, include a copy of | ||
468 | the License in the document and put the following copyright and | ||
469 | license notices just after the title page: | ||
470 | |||
471 | @smallexample | ||
472 | @group | ||
473 | Copyright (C) @var{year} @var{your name}. | ||
474 | Permission is granted to copy, distribute and/or modify this document | ||
475 | under the terms of the GNU Free Documentation License, Version 1.3 | ||
476 | or any later version published by the Free Software Foundation; | ||
477 | with no Invariant Sections, no Front-Cover Texts, and no Back-Cover | ||
478 | Texts. A copy of the license is included in the section entitled ``GNU | ||
479 | Free Documentation License''. | ||
480 | @end group | ||
481 | @end smallexample | ||
482 | |||
483 | If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, | ||
484 | replace the ``with@dots{}Texts.''@: line with this: | ||
485 | |||
486 | @smallexample | ||
487 | @group | ||
488 | with the Invariant Sections being @var{list their titles}, with | ||
489 | the Front-Cover Texts being @var{list}, and with the Back-Cover Texts | ||
490 | being @var{list}. | ||
491 | @end group | ||
492 | @end smallexample | ||
493 | |||
494 | If you have Invariant Sections without Cover Texts, or some other | ||
495 | combination of the three, merge those two alternatives to suit the | ||
496 | situation. | ||
497 | |||
498 | If your document contains nontrivial examples of program code, we | ||
499 | recommend releasing these examples in parallel under your choice of | ||
500 | free software license, such as the GNU General Public License, | ||
501 | to permit their use in free software. | ||
502 | |||
503 | @c Local Variables: | ||
504 | @c ispell-local-pdict: "ispell-dict" | ||
505 | @c End: | ||
diff --git a/doc/documentation/gendocs.sh b/doc/documentation/gendocs.sh new file mode 100755 index 000000000..3b71b36a2 --- /dev/null +++ b/doc/documentation/gendocs.sh | |||
@@ -0,0 +1,504 @@ | |||
1 | #!/bin/sh -e | ||
2 | # gendocs.sh -- generate a GNU manual in many formats. This script is | ||
3 | # mentioned in maintain.texi. See the help message below for usage details. | ||
4 | |||
5 | scriptversion=2016-12-31.18 | ||
6 | |||
7 | # Copyright 2003-2017 Free Software Foundation, Inc. | ||
8 | # | ||
9 | # This program is free software: you can redistribute it and/or modify | ||
10 | # it under the terms of the GNU General Public License as published by | ||
11 | # the Free Software Foundation; either version 3 of the License, or | ||
12 | # (at your option) any later version. | ||
13 | # | ||
14 | # This program is distributed in the hope that it will be useful, | ||
15 | # but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
16 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
17 | # GNU General Public License for more details. | ||
18 | # | ||
19 | # You should have received a copy of the GNU General Public License | ||
20 | # along with this program. If not, see <http://www.gnu.org/licenses/>. | ||
21 | # | ||
22 | # Original author: Mohit Agarwal. | ||
23 | # Send bug reports and any other correspondence to bug-gnulib@gnu.org. | ||
24 | # | ||
25 | # The latest version of this script, and the companion template, is | ||
26 | # available from the Gnulib repository: | ||
27 | # | ||
28 | # http://git.savannah.gnu.org/cgit/gnulib.git/tree/build-aux/gendocs.sh | ||
29 | # http://git.savannah.gnu.org/cgit/gnulib.git/tree/doc/gendocs_template | ||
30 | |||
31 | # TODO: | ||
32 | # - image importing was only implemented for HTML generated by | ||
33 | # makeinfo. But it should be simple enough to adjust. | ||
34 | # - images are not imported in the source tarball. All the needed | ||
35 | # formats (PDF, PNG, etc.) should be included. | ||
36 | |||
37 | prog=`basename "$0"` | ||
38 | srcdir=`pwd` | ||
39 | |||
40 | scripturl="http://git.savannah.gnu.org/cgit/gnulib.git/plain/build-aux/gendocs.sh" | ||
41 | templateurl="http://git.savannah.gnu.org/cgit/gnulib.git/plain/doc/gendocs_template" | ||
42 | |||
43 | : ${SETLANG="env LANG= LC_MESSAGES= LC_ALL= LANGUAGE="} | ||
44 | : ${MAKEINFO="makeinfo"} | ||
45 | : ${TEXI2DVI="texi2dvi"} | ||
46 | : ${DOCBOOK2HTML="docbook2html"} | ||
47 | : ${DOCBOOK2PDF="docbook2pdf"} | ||
48 | : ${DOCBOOK2TXT="docbook2txt"} | ||
49 | : ${GENDOCS_TEMPLATE_DIR="."} | ||
50 | : ${PERL='perl'} | ||
51 | : ${TEXI2HTML="texi2html"} | ||
52 | unset CDPATH | ||
53 | unset use_texi2html | ||
54 | |||
55 | MANUAL_TITLE= | ||
56 | PACKAGE= | ||
57 | EMAIL=webmasters@gnu.org # please override with --email | ||
58 | commonarg= # passed to all makeinfo/texi2html invcations. | ||
59 | dirargs= # passed to all tools (-I dir). | ||
60 | dirs= # -I directories. | ||
61 | htmlarg="--css-ref=/software/gnulib/manual.css -c TOP_NODE_UP_URL=/manual" | ||
62 | infoarg=--no-split | ||
63 | generate_ascii=true | ||
64 | generate_html=true | ||
65 | generate_info=true | ||
66 | generate_tex=true | ||
67 | outdir=manual | ||
68 | source_extra= | ||
69 | split=node | ||
70 | srcfile= | ||
71 | texarg="-t @finalout" | ||
72 | |||
73 | version="gendocs.sh $scriptversion | ||
74 | |||
75 | Copyright 2017 Free Software Foundation, Inc. | ||
76 | There is NO warranty. You may redistribute this software | ||
77 | under the terms of the GNU General Public License. | ||
78 | For more information about these matters, see the files named COPYING." | ||
79 | |||
80 | usage="Usage: $prog [OPTION]... PACKAGE MANUAL-TITLE | ||
81 | |||
82 | Generate output in various formats from PACKAGE.texinfo (or .texi or | ||
83 | .txi) source. See the GNU Maintainers document for a more extensive | ||
84 | discussion: | ||
85 | http://www.gnu.org/prep/maintain_toc.html | ||
86 | |||
87 | Options: | ||
88 | --email ADR use ADR as contact in generated web pages; always give this. | ||
89 | |||
90 | -s SRCFILE read Texinfo from SRCFILE, instead of PACKAGE.{texinfo|texi|txi} | ||
91 | -o OUTDIR write files into OUTDIR, instead of manual/. | ||
92 | -I DIR append DIR to the Texinfo search path. | ||
93 | --common ARG pass ARG in all invocations. | ||
94 | --html ARG pass ARG to makeinfo or texi2html for HTML targets, | ||
95 | instead of '$htmlarg'. | ||
96 | --info ARG pass ARG to makeinfo for Info, instead of --no-split. | ||
97 | --no-ascii skip generating the plain text output. | ||
98 | --no-html skip generating the html output. | ||
99 | --no-info skip generating the info output. | ||
100 | --no-tex skip generating the dvi and pdf output. | ||
101 | --source ARG include ARG in tar archive of sources. | ||
102 | --split HOW make split HTML by node, section, chapter; default node. | ||
103 | --tex ARG pass ARG to texi2dvi for DVI and PDF, instead of -t @finalout. | ||
104 | |||
105 | --texi2html use texi2html to make HTML target, with all split versions. | ||
106 | --docbook convert through DocBook too (xml, txt, html, pdf). | ||
107 | |||
108 | --help display this help and exit successfully. | ||
109 | --version display version information and exit successfully. | ||
110 | |||
111 | Simple example: $prog --email bug-gnu-emacs@gnu.org emacs \"GNU Emacs Manual\" | ||
112 | |||
113 | Typical sequence: | ||
114 | cd PACKAGESOURCE/doc | ||
115 | wget \"$scripturl\" | ||
116 | wget \"$templateurl\" | ||
117 | $prog --email BUGLIST MANUAL \"GNU MANUAL - One-line description\" | ||
118 | |||
119 | Output will be in a new subdirectory \"manual\" (by default; | ||
120 | use -o OUTDIR to override). Move all the new files into your web CVS | ||
121 | tree, as explained in the Web Pages node of maintain.texi. | ||
122 | |||
123 | Please use the --email ADDRESS option so your own bug-reporting | ||
124 | address will be used in the generated HTML pages. | ||
125 | |||
126 | MANUAL-TITLE is included as part of the HTML <title> of the overall | ||
127 | manual/index.html file. It should include the name of the package being | ||
128 | documented. manual/index.html is created by substitution from the file | ||
129 | $GENDOCS_TEMPLATE_DIR/gendocs_template. (Feel free to modify the | ||
130 | generic template for your own purposes.) | ||
131 | |||
132 | If you have several manuals, you'll need to run this script several | ||
133 | times with different MANUAL values, specifying a different output | ||
134 | directory with -o each time. Then write (by hand) an overall index.html | ||
135 | with links to them all. | ||
136 | |||
137 | If a manual's Texinfo sources are spread across several directories, | ||
138 | first copy or symlink all Texinfo sources into a single directory. | ||
139 | (Part of the script's work is to make a tar.gz of the sources.) | ||
140 | |||
141 | As implied above, by default monolithic Info files are generated. | ||
142 | If you want split Info, or other Info options, use --info to override. | ||
143 | |||
144 | You can set the environment variables MAKEINFO, TEXI2DVI, TEXI2HTML, | ||
145 | and PERL to control the programs that get executed, and | ||
146 | GENDOCS_TEMPLATE_DIR to control where the gendocs_template file is | ||
147 | looked for. With --docbook, the environment variables DOCBOOK2HTML, | ||
148 | DOCBOOK2PDF, and DOCBOOK2TXT are also consulted. | ||
149 | |||
150 | By default, makeinfo and texi2dvi are run in the default (English) | ||
151 | locale, since that's the language of most Texinfo manuals. If you | ||
152 | happen to have a non-English manual and non-English web site, see the | ||
153 | SETLANG setting in the source. | ||
154 | |||
155 | Email bug reports or enhancement requests to bug-gnulib@gnu.org. | ||
156 | " | ||
157 | |||
158 | while test $# -gt 0; do | ||
159 | case $1 in | ||
160 | -s) shift; srcfile=$1;; | ||
161 | -o) shift; outdir=$1;; | ||
162 | -I) shift; dirargs="$dirargs -I '$1'"; dirs="$dirs $1";; | ||
163 | --common) shift; commonarg=$1;; | ||
164 | --docbook) docbook=yes;; | ||
165 | --email) shift; EMAIL=$1;; | ||
166 | --html) shift; htmlarg=$1;; | ||
167 | --info) shift; infoarg=$1;; | ||
168 | --no-ascii) generate_ascii=false;; | ||
169 | --no-html) generate_ascii=false;; | ||
170 | --no-info) generate_info=false;; | ||
171 | --no-tex) generate_tex=false;; | ||
172 | --source) shift; source_extra=$1;; | ||
173 | --split) shift; split=$1;; | ||
174 | --tex) shift; texarg=$1;; | ||
175 | --texi2html) use_texi2html=1;; | ||
176 | |||
177 | --help) echo "$usage"; exit 0;; | ||
178 | --version) echo "$version"; exit 0;; | ||
179 | -*) | ||
180 | echo "$0: Unknown option \`$1'." >&2 | ||
181 | echo "$0: Try \`--help' for more information." >&2 | ||
182 | exit 1;; | ||
183 | *) | ||
184 | if test -z "$PACKAGE"; then | ||
185 | PACKAGE=$1 | ||
186 | elif test -z "$MANUAL_TITLE"; then | ||
187 | MANUAL_TITLE=$1 | ||
188 | else | ||
189 | echo "$0: extra non-option argument \`$1'." >&2 | ||
190 | exit 1 | ||
191 | fi;; | ||
192 | esac | ||
193 | shift | ||
194 | done | ||
195 | |||
196 | # makeinfo uses the dirargs, but texi2dvi doesn't. | ||
197 | commonarg=" $dirargs $commonarg" | ||
198 | |||
199 | # For most of the following, the base name is just $PACKAGE | ||
200 | base=$PACKAGE | ||
201 | |||
202 | if test -n "$srcfile"; then | ||
203 | # but here, we use the basename of $srcfile | ||
204 | base=`basename "$srcfile"` | ||
205 | case $base in | ||
206 | *.txi|*.texi|*.texinfo) base=`echo "$base"|sed 's/\.[texinfo]*$//'`;; | ||
207 | esac | ||
208 | PACKAGE=$base | ||
209 | elif test -s "$srcdir/$PACKAGE.texinfo"; then | ||
210 | srcfile=$srcdir/$PACKAGE.texinfo | ||
211 | elif test -s "$srcdir/$PACKAGE.texi"; then | ||
212 | srcfile=$srcdir/$PACKAGE.texi | ||
213 | elif test -s "$srcdir/$PACKAGE.txi"; then | ||
214 | srcfile=$srcdir/$PACKAGE.txi | ||
215 | else | ||
216 | echo "$0: cannot find .texinfo or .texi or .txi for $PACKAGE in $srcdir." >&2 | ||
217 | exit 1 | ||
218 | fi | ||
219 | |||
220 | if test ! -r $GENDOCS_TEMPLATE_DIR/gendocs_template; then | ||
221 | echo "$0: cannot read $GENDOCS_TEMPLATE_DIR/gendocs_template." >&2 | ||
222 | echo "$0: it is available from $templateurl." >&2 | ||
223 | exit 1 | ||
224 | fi | ||
225 | |||
226 | # Function to return size of $1 in something resembling kilobytes. | ||
227 | calcsize() | ||
228 | { | ||
229 | size=`ls -ksl $1 | awk '{print $1}'` | ||
230 | echo $size | ||
231 | } | ||
232 | |||
233 | # copy_images OUTDIR HTML-FILE... | ||
234 | # ------------------------------- | ||
235 | # Copy all the images needed by the HTML-FILEs into OUTDIR. | ||
236 | # Look for them in . and the -I directories; this is simpler than what | ||
237 | # makeinfo supports with -I, but hopefully it will suffice. | ||
238 | copy_images() | ||
239 | { | ||
240 | local odir | ||
241 | odir=$1 | ||
242 | shift | ||
243 | $PERL -n -e " | ||
244 | BEGIN { | ||
245 | \$me = '$prog'; | ||
246 | \$odir = '$odir'; | ||
247 | @dirs = qw(. $dirs); | ||
248 | } | ||
249 | " -e ' | ||
250 | /<img src="(.*?)"/g && ++$need{$1}; | ||
251 | |||
252 | END { | ||
253 | #print "$me: @{[keys %need]}\n"; # for debugging, show images found. | ||
254 | FILE: for my $f (keys %need) { | ||
255 | for my $d (@dirs) { | ||
256 | if (-f "$d/$f") { | ||
257 | use File::Basename; | ||
258 | my $dest = dirname ("$odir/$f"); | ||
259 | # | ||
260 | use File::Path; | ||
261 | -d $dest || mkpath ($dest) | ||
262 | || die "$me: cannot mkdir $dest: $!\n"; | ||
263 | # | ||
264 | use File::Copy; | ||
265 | copy ("$d/$f", $dest) | ||
266 | || die "$me: cannot copy $d/$f to $dest: $!\n"; | ||
267 | next FILE; | ||
268 | } | ||
269 | } | ||
270 | die "$me: $ARGV: cannot find image $f\n"; | ||
271 | } | ||
272 | } | ||
273 | ' -- "$@" || exit 1 | ||
274 | } | ||
275 | |||
276 | case $outdir in | ||
277 | /*) abs_outdir=$outdir;; | ||
278 | *) abs_outdir=$srcdir/$outdir;; | ||
279 | esac | ||
280 | |||
281 | echo "Making output for $srcfile" | ||
282 | echo " in `pwd`" | ||
283 | mkdir -p "$outdir/" | ||
284 | |||
285 | # | ||
286 | if $generate_info; then | ||
287 | cmd="$SETLANG $MAKEINFO -o $PACKAGE.info $commonarg $infoarg \"$srcfile\"" | ||
288 | echo "Generating info... ($cmd)" | ||
289 | rm -f $PACKAGE.info* # get rid of any strays | ||
290 | eval "$cmd" | ||
291 | tar czf "$outdir/$PACKAGE.info.tar.gz" $PACKAGE.info* | ||
292 | ls -l "$outdir/$PACKAGE.info.tar.gz" | ||
293 | info_tgz_size=`calcsize "$outdir/$PACKAGE.info.tar.gz"` | ||
294 | # do not mv the info files, there's no point in having them available | ||
295 | # separately on the web. | ||
296 | fi # end info | ||
297 | |||
298 | # | ||
299 | if $generate_tex; then | ||
300 | cmd="$SETLANG $TEXI2DVI $dirargs $texarg \"$srcfile\"" | ||
301 | printf "\nGenerating dvi... ($cmd)\n" | ||
302 | eval "$cmd" | ||
303 | # compress/finish dvi: | ||
304 | gzip -f -9 $PACKAGE.dvi | ||
305 | dvi_gz_size=`calcsize $PACKAGE.dvi.gz` | ||
306 | mv $PACKAGE.dvi.gz "$outdir/" | ||
307 | ls -l "$outdir/$PACKAGE.dvi.gz" | ||
308 | |||
309 | cmd="$SETLANG $TEXI2DVI --pdf $dirargs $texarg \"$srcfile\"" | ||
310 | printf "\nGenerating pdf... ($cmd)\n" | ||
311 | eval "$cmd" | ||
312 | pdf_size=`calcsize $PACKAGE.pdf` | ||
313 | mv $PACKAGE.pdf "$outdir/" | ||
314 | ls -l "$outdir/$PACKAGE.pdf" | ||
315 | fi # end tex (dvi + pdf) | ||
316 | |||
317 | # | ||
318 | if $generate_ascii; then | ||
319 | opt="-o $PACKAGE.txt --no-split --no-headers $commonarg" | ||
320 | cmd="$SETLANG $MAKEINFO $opt \"$srcfile\"" | ||
321 | printf "\nGenerating ascii... ($cmd)\n" | ||
322 | eval "$cmd" | ||
323 | ascii_size=`calcsize $PACKAGE.txt` | ||
324 | gzip -f -9 -c $PACKAGE.txt >"$outdir/$PACKAGE.txt.gz" | ||
325 | ascii_gz_size=`calcsize "$outdir/$PACKAGE.txt.gz"` | ||
326 | mv $PACKAGE.txt "$outdir/" | ||
327 | ls -l "$outdir/$PACKAGE.txt" "$outdir/$PACKAGE.txt.gz" | ||
328 | fi | ||
329 | |||
330 | # | ||
331 | |||
332 | if $generate_html; then | ||
333 | # Split HTML at level $1. Used for texi2html. | ||
334 | html_split() | ||
335 | { | ||
336 | opt="--split=$1 --node-files $commonarg $htmlarg" | ||
337 | cmd="$SETLANG $TEXI2HTML --output $PACKAGE.html $opt \"$srcfile\"" | ||
338 | printf "\nGenerating html by $1... ($cmd)\n" | ||
339 | eval "$cmd" | ||
340 | split_html_dir=$PACKAGE.html | ||
341 | ( | ||
342 | cd ${split_html_dir} || exit 1 | ||
343 | ln -sf ${PACKAGE}.html index.html | ||
344 | tar -czf "$abs_outdir/${PACKAGE}.html_$1.tar.gz" -- *.html | ||
345 | ) | ||
346 | eval html_$1_tgz_size=`calcsize "$outdir/${PACKAGE}.html_$1.tar.gz"` | ||
347 | rm -f "$outdir"/html_$1/*.html | ||
348 | mkdir -p "$outdir/html_$1/" | ||
349 | mv ${split_html_dir}/*.html "$outdir/html_$1/" | ||
350 | rmdir ${split_html_dir} | ||
351 | } | ||
352 | |||
353 | if test -z "$use_texi2html"; then | ||
354 | opt="--no-split --html -o $PACKAGE.html $commonarg $htmlarg" | ||
355 | cmd="$SETLANG $MAKEINFO $opt \"$srcfile\"" | ||
356 | printf "\nGenerating monolithic html... ($cmd)\n" | ||
357 | rm -rf $PACKAGE.html # in case a directory is left over | ||
358 | eval "$cmd" | ||
359 | html_mono_size=`calcsize $PACKAGE.html` | ||
360 | gzip -f -9 -c $PACKAGE.html >"$outdir/$PACKAGE.html.gz" | ||
361 | html_mono_gz_size=`calcsize "$outdir/$PACKAGE.html.gz"` | ||
362 | copy_images "$outdir/" $PACKAGE.html | ||
363 | mv $PACKAGE.html "$outdir/" | ||
364 | ls -l "$outdir/$PACKAGE.html" "$outdir/$PACKAGE.html.gz" | ||
365 | |||
366 | # Before Texinfo 5.0, makeinfo did not accept a --split=HOW option, | ||
367 | # it just always split by node. So if we're splitting by node anyway, | ||
368 | # leave it out. | ||
369 | if test "x$split" = xnode; then | ||
370 | split_arg= | ||
371 | else | ||
372 | split_arg=--split=$split | ||
373 | fi | ||
374 | # | ||
375 | opt="--html -o $PACKAGE.html $split_arg $commonarg $htmlarg" | ||
376 | cmd="$SETLANG $MAKEINFO $opt \"$srcfile\"" | ||
377 | printf "\nGenerating html by $split... ($cmd)\n" | ||
378 | eval "$cmd" | ||
379 | split_html_dir=$PACKAGE.html | ||
380 | copy_images $split_html_dir/ $split_html_dir/*.html | ||
381 | ( | ||
382 | cd $split_html_dir || exit 1 | ||
383 | tar -czf "$abs_outdir/$PACKAGE.html_$split.tar.gz" -- * | ||
384 | ) | ||
385 | eval \ | ||
386 | html_${split}_tgz_size=`calcsize "$outdir/$PACKAGE.html_$split.tar.gz"` | ||
387 | rm -rf "$outdir/html_$split/" | ||
388 | mv $split_html_dir "$outdir/html_$split/" | ||
389 | du -s "$outdir/html_$split/" | ||
390 | ls -l "$outdir/$PACKAGE.html_$split.tar.gz" | ||
391 | |||
392 | else # use texi2html: | ||
393 | opt="--output $PACKAGE.html $commonarg $htmlarg" | ||
394 | cmd="$SETLANG $TEXI2HTML $opt \"$srcfile\"" | ||
395 | printf "\nGenerating monolithic html with texi2html... ($cmd)\n" | ||
396 | rm -rf $PACKAGE.html # in case a directory is left over | ||
397 | eval "$cmd" | ||
398 | html_mono_size=`calcsize $PACKAGE.html` | ||
399 | gzip -f -9 -c $PACKAGE.html >"$outdir/$PACKAGE.html.gz" | ||
400 | html_mono_gz_size=`calcsize "$outdir/$PACKAGE.html.gz"` | ||
401 | mv $PACKAGE.html "$outdir/" | ||
402 | |||
403 | html_split node | ||
404 | html_split chapter | ||
405 | html_split section | ||
406 | fi | ||
407 | fi # end html | ||
408 | |||
409 | # | ||
410 | printf "\nMaking .tar.gz for sources...\n" | ||
411 | d=`dirname $srcfile` | ||
412 | ( | ||
413 | cd "$d" | ||
414 | srcfiles=`ls -d *.texinfo *.texi *.txi *.eps $source_extra 2>/dev/null` || true | ||
415 | tar czfh "$abs_outdir/$PACKAGE.texi.tar.gz" $srcfiles | ||
416 | ls -l "$abs_outdir/$PACKAGE.texi.tar.gz" | ||
417 | ) | ||
418 | texi_tgz_size=`calcsize "$outdir/$PACKAGE.texi.tar.gz"` | ||
419 | |||
420 | # | ||
421 | # Do everything again through docbook. | ||
422 | if test -n "$docbook"; then | ||
423 | opt="-o - --docbook $commonarg" | ||
424 | cmd="$SETLANG $MAKEINFO $opt \"$srcfile\" >${srcdir}/$PACKAGE-db.xml" | ||
425 | printf "\nGenerating docbook XML... ($cmd)\n" | ||
426 | eval "$cmd" | ||
427 | docbook_xml_size=`calcsize $PACKAGE-db.xml` | ||
428 | gzip -f -9 -c $PACKAGE-db.xml >"$outdir/$PACKAGE-db.xml.gz" | ||
429 | docbook_xml_gz_size=`calcsize "$outdir/$PACKAGE-db.xml.gz"` | ||
430 | mv $PACKAGE-db.xml "$outdir/" | ||
431 | |||
432 | split_html_db_dir=html_node_db | ||
433 | opt="$commonarg -o $split_html_db_dir" | ||
434 | cmd="$DOCBOOK2HTML $opt \"${outdir}/$PACKAGE-db.xml\"" | ||
435 | printf "\nGenerating docbook HTML... ($cmd)\n" | ||
436 | eval "$cmd" | ||
437 | ( | ||
438 | cd ${split_html_db_dir} || exit 1 | ||
439 | tar -czf "$abs_outdir/${PACKAGE}.html_node_db.tar.gz" -- *.html | ||
440 | ) | ||
441 | html_node_db_tgz_size=`calcsize "$outdir/${PACKAGE}.html_node_db.tar.gz"` | ||
442 | rm -f "$outdir"/html_node_db/*.html | ||
443 | mkdir -p "$outdir/html_node_db" | ||
444 | mv ${split_html_db_dir}/*.html "$outdir/html_node_db/" | ||
445 | rmdir ${split_html_db_dir} | ||
446 | |||
447 | cmd="$DOCBOOK2TXT \"${outdir}/$PACKAGE-db.xml\"" | ||
448 | printf "\nGenerating docbook ASCII... ($cmd)\n" | ||
449 | eval "$cmd" | ||
450 | docbook_ascii_size=`calcsize $PACKAGE-db.txt` | ||
451 | mv $PACKAGE-db.txt "$outdir/" | ||
452 | |||
453 | cmd="$DOCBOOK2PDF \"${outdir}/$PACKAGE-db.xml\"" | ||
454 | printf "\nGenerating docbook PDF... ($cmd)\n" | ||
455 | eval "$cmd" | ||
456 | docbook_pdf_size=`calcsize $PACKAGE-db.pdf` | ||
457 | mv $PACKAGE-db.pdf "$outdir/" | ||
458 | fi | ||
459 | |||
460 | # | ||
461 | printf "\nMaking index.html for $PACKAGE...\n" | ||
462 | if test -z "$use_texi2html"; then | ||
463 | CONDS="/%%IF *HTML_SECTION%%/,/%%ENDIF *HTML_SECTION%%/d;\ | ||
464 | /%%IF *HTML_CHAPTER%%/,/%%ENDIF *HTML_CHAPTER%%/d" | ||
465 | else | ||
466 | # should take account of --split here. | ||
467 | CONDS="/%%ENDIF.*%%/d;/%%IF *HTML_SECTION%%/d;/%%IF *HTML_CHAPTER%%/d" | ||
468 | fi | ||
469 | |||
470 | curdate=`$SETLANG date '+%B %d, %Y'` | ||
471 | sed \ | ||
472 | -e "s!%%TITLE%%!$MANUAL_TITLE!g" \ | ||
473 | -e "s!%%EMAIL%%!$EMAIL!g" \ | ||
474 | -e "s!%%PACKAGE%%!$PACKAGE!g" \ | ||
475 | -e "s!%%DATE%%!$curdate!g" \ | ||
476 | -e "s!%%HTML_MONO_SIZE%%!$html_mono_size!g" \ | ||
477 | -e "s!%%HTML_MONO_GZ_SIZE%%!$html_mono_gz_size!g" \ | ||
478 | -e "s!%%HTML_NODE_TGZ_SIZE%%!$html_node_tgz_size!g" \ | ||
479 | -e "s!%%HTML_SECTION_TGZ_SIZE%%!$html_section_tgz_size!g" \ | ||
480 | -e "s!%%HTML_CHAPTER_TGZ_SIZE%%!$html_chapter_tgz_size!g" \ | ||
481 | -e "s!%%INFO_TGZ_SIZE%%!$info_tgz_size!g" \ | ||
482 | -e "s!%%DVI_GZ_SIZE%%!$dvi_gz_size!g" \ | ||
483 | -e "s!%%PDF_SIZE%%!$pdf_size!g" \ | ||
484 | -e "s!%%ASCII_SIZE%%!$ascii_size!g" \ | ||
485 | -e "s!%%ASCII_GZ_SIZE%%!$ascii_gz_size!g" \ | ||
486 | -e "s!%%TEXI_TGZ_SIZE%%!$texi_tgz_size!g" \ | ||
487 | -e "s!%%DOCBOOK_HTML_NODE_TGZ_SIZE%%!$html_node_db_tgz_size!g" \ | ||
488 | -e "s!%%DOCBOOK_ASCII_SIZE%%!$docbook_ascii_size!g" \ | ||
489 | -e "s!%%DOCBOOK_PDF_SIZE%%!$docbook_pdf_size!g" \ | ||
490 | -e "s!%%DOCBOOK_XML_SIZE%%!$docbook_xml_size!g" \ | ||
491 | -e "s!%%DOCBOOK_XML_GZ_SIZE%%!$docbook_xml_gz_size!g" \ | ||
492 | -e "s,%%SCRIPTURL%%,$scripturl,g" \ | ||
493 | -e "s!%%SCRIPTNAME%%!$prog!g" \ | ||
494 | -e "$CONDS" \ | ||
495 | $GENDOCS_TEMPLATE_DIR/gendocs_template >"$outdir/index.html" | ||
496 | |||
497 | echo "Done, see $outdir/ subdirectory for new files." | ||
498 | |||
499 | # Local variables: | ||
500 | # eval: (add-hook 'write-file-hooks 'time-stamp) | ||
501 | # time-stamp-start: "scriptversion=" | ||
502 | # time-stamp-format: "%:y-%02m-%02d.%02H" | ||
503 | # time-stamp-end: "$" | ||
504 | # End: | ||
diff --git a/doc/documentation/gendocs_template b/doc/documentation/gendocs_template new file mode 100644 index 000000000..178f6cb4c --- /dev/null +++ b/doc/documentation/gendocs_template | |||
@@ -0,0 +1,91 @@ | |||
1 | <!--#include virtual="/server/header.html" --> | ||
2 | <!-- Parent-Version: 1.77 --> | ||
3 | <title>%%TITLE%% - GNU Project - Free Software Foundation</title> | ||
4 | <!--#include virtual="/server/banner.html" --> | ||
5 | <h2>%%TITLE%%</h2> | ||
6 | |||
7 | <address>Free Software Foundation</address> | ||
8 | <address>last updated %%DATE%%</address> | ||
9 | |||
10 | <p>This manual (%%PACKAGE%%) is available in the following formats:</p> | ||
11 | |||
12 | <ul> | ||
13 | <li><a href="%%PACKAGE%%.html">HTML | ||
14 | (%%HTML_MONO_SIZE%%K bytes)</a> - entirely on one web page.</li> | ||
15 | <li><a href="html_node/index.html">HTML</a> - with one web page per | ||
16 | node.</li> | ||
17 | %%IF HTML_SECTION%% | ||
18 | <li><a href="html_section/index.html">HTML</a> - with one web page per | ||
19 | section.</li> | ||
20 | %%ENDIF HTML_SECTION%% | ||
21 | %%IF HTML_CHAPTER%% | ||
22 | <li><a href="html_chapter/index.html">HTML</a> - with one web page per | ||
23 | chapter.</li> | ||
24 | %%ENDIF HTML_CHAPTER%% | ||
25 | <li><a href="%%PACKAGE%%.html.gz">HTML compressed | ||
26 | (%%HTML_MONO_GZ_SIZE%%K gzipped characters)</a> - entirely on | ||
27 | one web page.</li> | ||
28 | <li><a href="%%PACKAGE%%.html_node.tar.gz">HTML compressed | ||
29 | (%%HTML_NODE_TGZ_SIZE%%K gzipped tar file)</a> - | ||
30 | with one web page per node.</li> | ||
31 | %%IF HTML_SECTION%% | ||
32 | <li><a href="%%PACKAGE%%.html_section.tar.gz">HTML compressed | ||
33 | (%%HTML_SECTION_TGZ_SIZE%%K gzipped tar file)</a> - | ||
34 | with one web page per section.</li> | ||
35 | %%ENDIF HTML_SECTION%% | ||
36 | %%IF HTML_CHAPTER%% | ||
37 | <li><a href="%%PACKAGE%%.html_chapter.tar.gz">HTML compressed | ||
38 | (%%HTML_CHAPTER_TGZ_SIZE%%K gzipped tar file)</a> - | ||
39 | with one web page per chapter.</li> | ||
40 | %%ENDIF HTML_CHAPTER%% | ||
41 | <li><a href="%%PACKAGE%%.info.tar.gz">Info document | ||
42 | (%%INFO_TGZ_SIZE%%K bytes gzipped tar file)</a>.</li> | ||
43 | <li><a href="%%PACKAGE%%.txt">ASCII text | ||
44 | (%%ASCII_SIZE%%K bytes)</a>.</li> | ||
45 | <li><a href="%%PACKAGE%%.txt.gz">ASCII text compressed | ||
46 | (%%ASCII_GZ_SIZE%%K bytes gzipped)</a>.</li> | ||
47 | <li><a href="%%PACKAGE%%.dvi.gz">TeX dvi file | ||
48 | (%%DVI_GZ_SIZE%%K bytes gzipped)</a>.</li> | ||
49 | <li><a href="%%PACKAGE%%.pdf">PDF file | ||
50 | (%%PDF_SIZE%%K bytes)</a>.</li> | ||
51 | <li><a href="%%PACKAGE%%.texi.tar.gz">Texinfo source | ||
52 | (%%TEXI_TGZ_SIZE%%K bytes gzipped tar file).</a></li> | ||
53 | </ul> | ||
54 | |||
55 | <p>You can <a href="http://shop.fsf.org/">buy printed copies of | ||
56 | some manuals</a> (among other items) from the Free Software Foundation; | ||
57 | this helps support FSF activities.</p> | ||
58 | |||
59 | <p>(This page generated by the <a href="%%SCRIPTURL%%">%%SCRIPTNAME%% | ||
60 | script</a>.)</p> | ||
61 | |||
62 | <!-- If needed, change the copyright block at the bottom. In general, | ||
63 | all pages on the GNU web server should have the section about | ||
64 | verbatim copying. Please do NOT remove this without talking | ||
65 | with the webmasters first. | ||
66 | Please make sure the copyright date is consistent with the document | ||
67 | and that it is like this: "2001, 2002", not this: "2001-2002". --> | ||
68 | </div><!-- for id="content", starts in the include above --> | ||
69 | <!--#include virtual="/server/footer.html" --> | ||
70 | <div id="footer"> | ||
71 | <div class="unprintable"> | ||
72 | |||
73 | <p>Please send general FSF & GNU inquiries to | ||
74 | <a href="mailto:gnu@gnu.org"><gnu@gnu.org></a>. | ||
75 | There are also <a href="/contact/">other ways to contact</a> | ||
76 | the FSF. Broken links and other corrections or suggestions can be sent | ||
77 | to <a href="mailto:%%EMAIL%%"><%%EMAIL%%></a>.</p> | ||
78 | </div> | ||
79 | |||
80 | <p>Copyright © 2017 Free Software Foundation, Inc.</p> | ||
81 | |||
82 | <p>This page is licensed under a <a rel="license" | ||
83 | href="http://creativecommons.org/licenses/by-nd/3.0/us/">Creative | ||
84 | Commons Attribution-NoDerivs 3.0 United States License</a>.</p> | ||
85 | |||
86 | <!--#include virtual="/server/bottom-notes.html" --> | ||
87 | |||
88 | </div> | ||
89 | </div> | ||
90 | </body> | ||
91 | </html> | ||
diff --git a/doc/documentation/gendocs_template_min b/doc/documentation/gendocs_template_min new file mode 100644 index 000000000..112fa3bfb --- /dev/null +++ b/doc/documentation/gendocs_template_min | |||
@@ -0,0 +1,93 @@ | |||
1 | <?xml version="1.0" encoding="utf-8" ?> | ||
2 | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" | ||
3 | "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> | ||
4 | <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"> | ||
5 | |||
6 | <head> | ||
7 | <title>%%TITLE%% - GNU Project - Free Software Foundation</title> | ||
8 | <meta http-equiv="content-type" content='text/html; charset=utf-8' /> | ||
9 | <link rel="stylesheet" type="text/css" href="/gnu.css" /> | ||
10 | </head> | ||
11 | |||
12 | <body> | ||
13 | |||
14 | <h3>%%TITLE%%</h3> | ||
15 | |||
16 | <address>Free Software Foundation</address> | ||
17 | <address>last updated %%DATE%%</address> | ||
18 | <p> | ||
19 | <a href="/graphics/gnu-head.jpg"> | ||
20 | <img src="/graphics/gnu-head-sm.jpg" | ||
21 | alt=" [image of the head of a GNU] " width="129" height="122"/> | ||
22 | </a> | ||
23 | </p> | ||
24 | <hr /> | ||
25 | |||
26 | <p>This manual (%%PACKAGE%%) is available in the following formats:</p> | ||
27 | |||
28 | <ul> | ||
29 | <li><a href="%%PACKAGE%%.html">HTML | ||
30 | (%%HTML_MONO_SIZE%%K bytes)</a> - entirely on one web page.</li> | ||
31 | <li><a href="html_node/index.html">HTML</a> - with one web page per | ||
32 | node.</li> | ||
33 | %%IF HTML_SECTION%% | ||
34 | <li><a href="html_section/index.html">HTML</a> - with one web page per | ||
35 | section.</li> | ||
36 | %%ENDIF HTML_SECTION%% | ||
37 | %%IF HTML_CHAPTER%% | ||
38 | <li><a href="html_chapter/index.html">HTML</a> - with one web page per | ||
39 | chapter.</li> | ||
40 | %%ENDIF HTML_CHAPTER%% | ||
41 | <li><a href="%%PACKAGE%%.html.gz">HTML compressed | ||
42 | (%%HTML_MONO_GZ_SIZE%%K gzipped characters)</a> - entirely on | ||
43 | one web page.</li> | ||
44 | <li><a href="%%PACKAGE%%.html_node.tar.gz">HTML compressed | ||
45 | (%%HTML_NODE_TGZ_SIZE%%K gzipped tar file)</a> - | ||
46 | with one web page per node.</li> | ||
47 | %%IF HTML_SECTION%% | ||
48 | <li><a href="%%PACKAGE%%.html_section.tar.gz">HTML compressed | ||
49 | (%%HTML_SECTION_TGZ_SIZE%%K gzipped tar file)</a> - | ||
50 | with one web page per section.</li> | ||
51 | %%ENDIF HTML_SECTION%% | ||
52 | %%IF HTML_CHAPTER%% | ||
53 | <li><a href="%%PACKAGE%%.html_chapter.tar.gz">HTML compressed | ||
54 | (%%HTML_CHAPTER_TGZ_SIZE%%K gzipped tar file)</a> - | ||
55 | with one web page per chapter.</li> | ||
56 | %%ENDIF HTML_CHAPTER%% | ||
57 | <li><a href="%%PACKAGE%%.info.tar.gz">Info document | ||
58 | (%%INFO_TGZ_SIZE%%K bytes gzipped tar file)</a>.</li> | ||
59 | <li><a href="%%PACKAGE%%.txt">ASCII text | ||
60 | (%%ASCII_SIZE%%K bytes)</a>.</li> | ||
61 | <li><a href="%%PACKAGE%%.txt.gz">ASCII text compressed | ||
62 | (%%ASCII_GZ_SIZE%%K bytes gzipped)</a>.</li> | ||
63 | <li><a href="%%PACKAGE%%.dvi.gz">TeX dvi file | ||
64 | (%%DVI_GZ_SIZE%%K bytes gzipped)</a>.</li> | ||
65 | <li><a href="%%PACKAGE%%.pdf">PDF file | ||
66 | (%%PDF_SIZE%%K bytes)</a>.</li> | ||
67 | <li><a href="%%PACKAGE%%.texi.tar.gz">Texinfo source | ||
68 | (%%TEXI_TGZ_SIZE%%K bytes gzipped tar file).</a></li> | ||
69 | </ul> | ||
70 | |||
71 | <p>(This page generated by the <a href="%%SCRIPTURL%%">%%SCRIPTNAME%% | ||
72 | script</a>.)</p> | ||
73 | |||
74 | <div id="footer" class="copyright"> | ||
75 | |||
76 | <p>Please send general FSF & GNU inquiries to | ||
77 | <a href="mailto:gnu@gnu.org"><gnu@gnu.org></a>. | ||
78 | There are also <a href="/contact/">other ways to contact</a> | ||
79 | the FSF. Broken links and other corrections or suggestions can be sent | ||
80 | to <a href="mailto:%%EMAIL%%"><%%EMAIL%%></a>.</p> | ||
81 | </div> | ||
82 | |||
83 | <p>Copyright © 2017 Free Software Foundation, Inc.</p> | ||
84 | |||
85 | <p>This page is licensed under a <a rel="license" | ||
86 | href="http://creativecommons.org/licenses/by-nd/3.0/us/">Creative | ||
87 | Commons Attribution-NoDerivs 3.0 United States License</a>.</p> | ||
88 | |||
89 | <!--#include virtual="/server/bottom-notes.html" --> | ||
90 | |||
91 | </div> | ||
92 | </body> | ||
93 | </html> | ||
diff --git a/doc/documentation/gnunet-c-tutorial.texi b/doc/documentation/gnunet-c-tutorial.texi new file mode 100644 index 000000000..f39c7de64 --- /dev/null +++ b/doc/documentation/gnunet-c-tutorial.texi | |||
@@ -0,0 +1,1540 @@ | |||
1 | \input texinfo | ||
2 | @c %**start of header | ||
3 | @setfilename gnunet-c-tutorial.info | ||
4 | @documentencoding UTF-8 | ||
5 | @settitle GNUnet C Tutorial | ||
6 | @exampleindent 2 | ||
7 | @c %**end of header | ||
8 | |||
9 | @c including 'version.texi' makes makeinfo throw errors. | ||
10 | @include version2.texi | ||
11 | |||
12 | @copying | ||
13 | Copyright @copyright{} 2001-2017 GNUnet e.V. | ||
14 | |||
15 | Permission is granted to copy, distribute and/or modify this document | ||
16 | under the terms of the GNU Free Documentation License, Version 1.3 or | ||
17 | any later version published by the Free Software Foundation; with no | ||
18 | Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A | ||
19 | copy of the license is included in the section entitled ``GNU Free | ||
20 | Documentation License''. | ||
21 | |||
22 | A copy of the license is also available from the Free Software | ||
23 | Foundation Web site at @url{http://www.gnu.org/licenses/fdl.html}. | ||
24 | |||
25 | Alternately, this document is also available under the General | ||
26 | Public License, version 3 or later, as published by the Free Software | ||
27 | Foundation. A copy of the license is included in the section entitled | ||
28 | ``GNU General Public License''. | ||
29 | |||
30 | A copy of the license is also available from the Free Software | ||
31 | Foundation Web site at @url{http://www.gnu.org/licenses/gpl.html}. | ||
32 | @end copying | ||
33 | |||
34 | @dircategory Tutorial | ||
35 | @direntry | ||
36 | * GNUnet-C-Tutorial: (gnunet-c-tutorial). C Tutorial for GNunet | ||
37 | @end direntry | ||
38 | |||
39 | |||
40 | @titlepage | ||
41 | @title GNUnet C Tutorial | ||
42 | @subtitle A Tutorial for GNUnet @value{VERSION} (C version) | ||
43 | @author The GNUnet Developers | ||
44 | |||
45 | @page | ||
46 | @vskip 0pt plus 1filll | ||
47 | |||
48 | @insertcopying | ||
49 | @end titlepage | ||
50 | |||
51 | @contents | ||
52 | |||
53 | @c **** TODO | ||
54 | @c 1. Update content? | ||
55 | @c 2. Either reference main documentation or | ||
56 | @c 3. Merge this into main documentation | ||
57 | |||
58 | @node Top | ||
59 | @top Introduction | ||
60 | |||
61 | This tutorials explains how to install GNUnet on a | ||
62 | GNU/Linux system and gives an introduction on how | ||
63 | GNUnet can be used to develop a Peer-to-Peer application. | ||
64 | Detailed installation instructions for | ||
65 | various operating systems and a detailed list of all | ||
66 | dependencies can be found on our website at | ||
67 | @uref{https://gnunet.org/installation} and in our | ||
68 | Reference Documentation (GNUnet Handbook). | ||
69 | |||
70 | Please read this tutorial carefully since every single step is | ||
71 | important and do not hesitate to contact the GNUnet team if you have | ||
72 | any questions or problems! Check here how to contact the GNUnet | ||
73 | team: @uref{https://gnunet.org/contact_information} | ||
74 | |||
75 | @menu | ||
76 | |||
77 | * Installing GNUnet:: Installing GNUnet | ||
78 | * Introduction to GNUnet Architecture:: Introduction to GNUnet Architecture | ||
79 | * First Steps with GNUnet:: First Steps with GNUnet | ||
80 | * Developing Applications:: Developing Applications | ||
81 | |||
82 | @detailmenu | ||
83 | --- The Detailed Node Listing --- | ||
84 | |||
85 | Installing GNUnet | ||
86 | |||
87 | * Obtaining a stable version:: | ||
88 | * Installing Build Tool Chain and Dependencies:: | ||
89 | * Obtaining the latest version from Git:: | ||
90 | * Compiling and Installing GNUnet:: | ||
91 | * Common Issues - Check your GNUnet installation:: | ||
92 | |||
93 | Introduction to GNUnet Architecture | ||
94 | |||
95 | First Steps with GNUnet | ||
96 | |||
97 | * Configure your peer:: | ||
98 | * Start a peer:: | ||
99 | * Monitor a peer:: | ||
100 | * Starting Two Peers by Hand:: | ||
101 | * Starting Peers Using the Testbed Service:: | ||
102 | |||
103 | Developing Applications | ||
104 | |||
105 | * gnunet-ext:: | ||
106 | * Adapting the Template:: | ||
107 | * Writing a Client Application:: | ||
108 | * Writing a Service:: | ||
109 | * Interacting directly with other Peers using the CORE Service:: | ||
110 | * Storing peer-specific data using the PEERSTORE service:: | ||
111 | * Using the DHT:: | ||
112 | * Debugging with gnunet-arm:: | ||
113 | |||
114 | @end detailmenu | ||
115 | @end menu | ||
116 | |||
117 | @node Installing GNUnet | ||
118 | @chapter Installing GNUnet | ||
119 | |||
120 | First of all you have to install a current version of GNUnet. | ||
121 | You can download a tarball of a stable version from GNU FTP mirrors | ||
122 | or obtain the latest development version from our Git repository. | ||
123 | |||
124 | Most of the time you should prefer to download the stable version | ||
125 | since with the latest development version things can be broken, | ||
126 | functionality can be changed or tests can fail. You should only use | ||
127 | the development version if you know that you require a certain | ||
128 | feature or a certain issue has been fixed since the last release. | ||
129 | |||
130 | @menu | ||
131 | * Obtaining a stable version:: | ||
132 | * Installing Build Tool Chain and Dependencies:: | ||
133 | * Obtaining the latest version from Git:: | ||
134 | * Compiling and Installing GNUnet:: | ||
135 | * Common Issues - Check your GNUnet installation:: | ||
136 | @end menu | ||
137 | |||
138 | @node Obtaining a stable version | ||
139 | @section Obtaining a stable version | ||
140 | |||
141 | Download the tarball from | ||
142 | @indicateurl{https://ftp.gnu.org/gnu/gnunet/gnunet-@value{VERSION}.tar.gz}. | ||
143 | |||
144 | Make sure to download the associated @file{.sig} file and to verify the | ||
145 | authenticity of the tarball against it, like this: | ||
146 | |||
147 | @example | ||
148 | $ wget https://ftp.gnu.org/gnu/gnunet/gnunet-@value{VERSION}.tar.gz.sig | ||
149 | $ gpg --verify-files gnunet-@value{VERSION}.tar.gz.sig | ||
150 | @end example | ||
151 | |||
152 | @noindent | ||
153 | If this command fails because you do not have the required public key, | ||
154 | then you need to run this command to import it: | ||
155 | |||
156 | @example | ||
157 | $ gpg --keyserver keys.gnupg.net --recv-keys 48426C7E | ||
158 | @end example | ||
159 | |||
160 | @noindent | ||
161 | and rerun the @code{gpg --verify-files} command. | ||
162 | |||
163 | @b{Note:}@ | ||
164 | @b{The pub key to sign the 0.10.1 release has been | ||
165 | revoked}. You will get an error message stating that | ||
166 | @b{there is no known public key or that it has been revoked}. | ||
167 | The next release of GNUnet will have a valid signature | ||
168 | again. We are sorry for the inconvenience this causes. | ||
169 | Another possible source you could use is our | ||
170 | "gnunet" git repository which has mandatory signed commits | ||
171 | by every developer. | ||
172 | |||
173 | Now you can extract the tarball and rename the resulting | ||
174 | directory to @file{gnunet} which we will be using in the | ||
175 | remainder of this document. | ||
176 | |||
177 | @example | ||
178 | $ tar xvzf gnunet-@value{VERSION}.tar.gz | ||
179 | $ mv gnunet-@value{VERSION} gnunet | ||
180 | $ cd gnunet | ||
181 | @end example | ||
182 | |||
183 | @noindent | ||
184 | However, please note that stable versions can be very outdated. | ||
185 | As a developer you are @b{strongly} encouraged to use the version | ||
186 | from @uref{https://gnunet.org/git/, git}. | ||
187 | |||
188 | @node Installing Build Tool Chain and Dependencies | ||
189 | @section Installing Build Tool Chain and Dependencies | ||
190 | |||
191 | To successfully compile GNUnet, you need the tools to build GNUnet and | ||
192 | the required dependencies. Please take a look at the | ||
193 | GNUnet Reference Documentation | ||
194 | (@pxref{Dependencies, The GNUnet Reference Documentation,, gnunet, The GNUnet Reference Documentation}) | ||
195 | for a list of required dependencies | ||
196 | and | ||
197 | (@pxref{Generic installation instructions, The GNUnet Reference Documentation,, gnunet, The GNUnet Reference Documentation}) | ||
198 | read its Installation chapter for specific instructions for | ||
199 | your operating system. | ||
200 | Please check the notes at the end of the configure process about | ||
201 | required dependencies. | ||
202 | |||
203 | For GNUnet bootstrapping support and the HTTP(S) plugin you should | ||
204 | install @uref{https://gnunet.org/gnurl, libgnurl}. | ||
205 | For the filesharing service you should install at least one of the | ||
206 | datastore backends. MySQL, SQlite and PostgreSQL are supported. | ||
207 | |||
208 | @node Obtaining the latest version from Git | ||
209 | @section Obtaining the latest version from Git | ||
210 | |||
211 | The latest development version can obtained from our Git repository. | ||
212 | To obtain the code you need to have @code{Git} installed, which is | ||
213 | required for obtaining the repository via: | ||
214 | |||
215 | @example | ||
216 | $ git clone https://gnunet.org/git/gnunet | ||
217 | @end example | ||
218 | |||
219 | @noindent | ||
220 | After cloning the repository you have to execute the @file{bootstrap} | ||
221 | script in the new directory: | ||
222 | |||
223 | @example | ||
224 | $ cd gnunet | ||
225 | $ ./bootstrap | ||
226 | @end example | ||
227 | |||
228 | @noindent | ||
229 | The remainder of this tutorial will assume that you have the | ||
230 | Git branch ``master'' checked out. | ||
231 | |||
232 | @node Compiling and Installing GNUnet | ||
233 | @section Compiling and Installing GNUnet | ||
234 | |||
235 | Note: This section is a duplication of the more in depth | ||
236 | @pxref{GNUnet Installation Handbook, The GNUnet Reference Documentation,, gnunet, The GNUnet Reference Documentation}. | ||
237 | |||
238 | First, you need to install libgnupgerror @geq{} 1.27 and | ||
239 | libgcrypt @geq{} 1.7.6: | ||
240 | |||
241 | @example | ||
242 | $ export GNUPGFTP="https://www.gnupg.org/ftp/gcrypt" | ||
243 | $ wget $GNUPGFTP/libgpg-error/libgpg-error-1.27.tar.bz2 | ||
244 | $ tar xf libgpg-error-1.27.tar.bz2 | ||
245 | $ cd libgpg-error-1.27 | ||
246 | $ ./configure | ||
247 | $ sudo make install | ||
248 | $ cd .. | ||
249 | @end example | ||
250 | |||
251 | @example | ||
252 | $ export GNUPGFTP="https://www.gnupg.org/ftp/gcrypt" | ||
253 | $ wget $GNUPGFTP/libgcrypt/libgcrypt-1.7.6.tar.bz2 | ||
254 | $ tar xf libgcrypt-1.7.6.tar.bz2 | ||
255 | $ cd libgcrypt-1.7.6 | ||
256 | $ ./configure | ||
257 | $ sudo make install | ||
258 | $ cd .. | ||
259 | @end example | ||
260 | |||
261 | @menu | ||
262 | * Installation:: | ||
263 | @end menu | ||
264 | |||
265 | @node Installation | ||
266 | @subsection Installation | ||
267 | Assuming all dependencies are installed, the following commands will | ||
268 | compile and install GNUnet in your home directory. You can specify the | ||
269 | directory where GNUnet will be installed by changing the | ||
270 | @code{--prefix} value when calling @command{./configure}. If | ||
271 | you do not specifiy a prefix, GNUnet is installed in the directory | ||
272 | @file{/usr/local}. When developing new applications you may want | ||
273 | to enable verbose logging by adding @code{--enable-logging=verbose}: | ||
274 | |||
275 | @example | ||
276 | $ ./configure --prefix=$PREFIX --enable-logging | ||
277 | $ make | ||
278 | $ make install | ||
279 | @end example | ||
280 | |||
281 | @noindent | ||
282 | After installing GNUnet you have to add your GNUnet installation | ||
283 | to your path environmental variable. In addition you have to | ||
284 | create the @file{.config} directory in your home directory | ||
285 | (unless it already exists) where GNUnet stores its data and an | ||
286 | empty GNUnet configuration file: | ||
287 | |||
288 | @example | ||
289 | $ export PATH=$PATH:$PREFIX/bin | ||
290 | $ echo export PATH=$PREFIX/bin:\\$PATH >> ~/.bashrc | ||
291 | $ mkdir ~/.config/ | ||
292 | $ touch ~/.config/gnunet.conf | ||
293 | @end example | ||
294 | |||
295 | @node Common Issues - Check your GNUnet installation | ||
296 | @section Common Issues - Check your GNUnet installation | ||
297 | |||
298 | You should check your installation to ensure that installing GNUnet | ||
299 | was successful up to this point. You should be able to access GNUnet's | ||
300 | binaries and run GNUnet's self check. | ||
301 | |||
302 | @example | ||
303 | $ which gnunet-arm | ||
304 | @end example | ||
305 | |||
306 | @noindent | ||
307 | should return $PREFIX/bin/gnunet-arm. It should be located in your | ||
308 | GNUnet installation and the output should not be empty. | ||
309 | If you see an output like: | ||
310 | |||
311 | @example | ||
312 | $ which gnunet-arm | ||
313 | @end example | ||
314 | |||
315 | @noindent | ||
316 | check your PATH variable to ensure GNUnet's @file{bin} directory is | ||
317 | included. | ||
318 | |||
319 | GNUnet provides tests for all of its subcomponents. Run | ||
320 | |||
321 | @example | ||
322 | $ make check | ||
323 | @end example | ||
324 | |||
325 | @noindent | ||
326 | to execute tests for all components. @command{make check} traverses all | ||
327 | subdirectories in @file{src}. For every subdirectory you should | ||
328 | get a message like this: | ||
329 | |||
330 | @example | ||
331 | make[2]: Entering directory `/home/$USER/gnunet/contrib' | ||
332 | PASS: test_gnunet_prefix | ||
333 | ============= | ||
334 | 1 test passed | ||
335 | ============= | ||
336 | @end example | ||
337 | |||
338 | @node Introduction to GNUnet Architecture | ||
339 | @chapter Introduction to GNUnet Architecture | ||
340 | |||
341 | GNUnet is organized in layers and services. Each service is composed of a | ||
342 | main service implementation and a client library for other programs to use | ||
343 | the service's functionality, described by an API. | ||
344 | @c This approach is shown in | ||
345 | @c FIXME: enable this once the commented block below works: | ||
346 | @c figure~\ref fig:service. | ||
347 | Some services provide an additional command line tool to enable the user | ||
348 | to interact with the service. | ||
349 | |||
350 | Very often it is other GNUnet services that will use these APIs to build | ||
351 | the higher layers of GNUnet on top of the lower ones. Each layer expands | ||
352 | or extends the functionality of the service below (for instance, to build | ||
353 | a mesh on top of a DHT). | ||
354 | @c FXIME: See comment above. | ||
355 | @c See figure ~\ref fig:interaction for an illustration of this approach. | ||
356 | |||
357 | @c ** @image filename[, width[, height[, alttext[, extension]]]] | ||
358 | @c FIXME: Texlive (?) 20112 makes the assumption that this means | ||
359 | @c 'images/OBJECTNAME.txt' but later versions of it (2017) use this | ||
360 | @c syntax as described below. | ||
361 | @c TODO: Checkout the makedoc script Guile uses. | ||
362 | |||
363 | @c FIXME!!! | ||
364 | @c @image{images/gnunet-tutorial-service,,5in,Service with API and network protocol,.png} | ||
365 | @c @image{images/gnunet-tutorial-system,,5in,The layered system architecture of GNUnet,.png} | ||
366 | |||
367 | @c \begin{figure}[!h] | ||
368 | @c \begin{center} | ||
369 | @c % \begin{subfigure} | ||
370 | @c \begin{subfigure}[b]{0.3\textwidth} | ||
371 | @c \centering | ||
372 | @c \includegraphics[width=\textwidth]{figs/Service.pdf} | ||
373 | @c \caption{Service with API and network protocol} | ||
374 | @c \label{fig:service} | ||
375 | @c \end{subfigure} | ||
376 | @c ~~~~~~~~~~ | ||
377 | @c \begin{subfigure}[b]{0.3\textwidth} | ||
378 | @c \centering | ||
379 | @c \includegraphics[width=\textwidth]{figs/System.pdf} | ||
380 | @c \caption{Service interaction} | ||
381 | @c \label{fig:interaction} | ||
382 | @c \end{subfigure} | ||
383 | @c \end{center} | ||
384 | @c \caption{GNUnet's layered system architecture} | ||
385 | @c \end{figure} | ||
386 | |||
387 | The main service implementation runs as a standalone process in the | ||
388 | operating system and the client code runs as part of the client program, | ||
389 | so crashes of a client do not affect the service process or other clients. | ||
390 | The service and the clients communicate via a message protocol to be | ||
391 | defined and implemented by the programmer. | ||
392 | |||
393 | @node First Steps with GNUnet | ||
394 | @chapter First Steps with GNUnet | ||
395 | |||
396 | @menu | ||
397 | * Configure your peer:: | ||
398 | * Start a peer:: | ||
399 | * Monitor a peer:: | ||
400 | * Starting Two Peers by Hand:: | ||
401 | * Starting Peers Using the Testbed Service:: | ||
402 | @end menu | ||
403 | |||
404 | @node Configure your peer | ||
405 | @section Configure your peer | ||
406 | |||
407 | First of all we need to configure your peer. Each peer is started with | ||
408 | a configuration containing settings for GNUnet itself and its services. | ||
409 | This configuration is based on the default configuration shipped with | ||
410 | GNUnet and can be modified. The default configuration is located in the | ||
411 | @file{$PREFIX/share/gnunet/config.d} directory. When starting a peer, you | ||
412 | can specify a customized configuration using the the @command{-c} command | ||
413 | line switch when starting the ARM service and all other services. When | ||
414 | using a modified configuration the default values are loaded and only | ||
415 | values specified in the configuration file will replace the default | ||
416 | values. | ||
417 | |||
418 | Since we want to start additional peers later, we need some modifications | ||
419 | from the default configuration. We need to create a separate service | ||
420 | home and a file containing our modifications for this peer: | ||
421 | |||
422 | @example | ||
423 | $ mkdir ~/gnunet1/ | ||
424 | $ touch peer1.conf | ||
425 | @end example | ||
426 | |||
427 | @noindent | ||
428 | Now add the following lines to @file{peer1.conf} to use this directory. | ||
429 | For simplified usage we want to prevent the peer to connect to the GNUnet | ||
430 | network since this could lead to confusing output. This modifications | ||
431 | will replace the default settings: | ||
432 | |||
433 | @example | ||
434 | [PATHS] | ||
435 | # Use this directory to store GNUnet data | ||
436 | GNUNET_HOME = ~/gnunet1/ | ||
437 | [hostlist] | ||
438 | # prevent bootstrapping | ||
439 | SERVERS = | ||
440 | @end example | ||
441 | |||
442 | @node Start a peer | ||
443 | @section Start a peer | ||
444 | Each GNUnet instance (called peer) has an identity (peer ID) based on a | ||
445 | cryptographic public private key pair. The peer ID is the printable hash | ||
446 | of the public key. | ||
447 | |||
448 | GNUnet services are controlled by a master service, the so called | ||
449 | @dfn{Automatic Restart Manager} (ARM). ARM starts, stops and even | ||
450 | restarts services automatically or on demand when a client connects. | ||
451 | You interact with the ARM service using the @command{gnunet-arm} tool. | ||
452 | GNUnet can then be started with @command{gnunet-arm -s} and stopped with | ||
453 | @command{gnunet-arm -e}. An additional service not automatically started | ||
454 | can be started using @command{gnunet-arm -i <service name>} and stopped | ||
455 | using @command{gnunet-arm -k <servicename>}. | ||
456 | |||
457 | Once you have started your peer, you can use many other GNUnet commands | ||
458 | to interact with it. For example, you can run: | ||
459 | |||
460 | @example | ||
461 | $ gnunet-peerinfo -s | ||
462 | @end example | ||
463 | |||
464 | @noindent | ||
465 | to obtain the public key of your peer. | ||
466 | |||
467 | You should see an output containing the peer ID similar to: | ||
468 | |||
469 | @example | ||
470 | I am peer `0PA02UVRKQTS2C .. JL5Q78F6H0B1ACPV1CJI59MEQUMQCC5G'. | ||
471 | @end example | ||
472 | |||
473 | @node Monitor a peer | ||
474 | @section Monitor a peer | ||
475 | |||
476 | In this section, we will monitor the behaviour of our peer's DHT | ||
477 | service with respect to a specific key. First we will start | ||
478 | GNUnet and then start the DHT service and use the DHT monitor tool | ||
479 | to monitor the PUT and GET commands we issue ussing the | ||
480 | @command{gnunet-dht-put} and @command{gnunet-dht-get} commands. | ||
481 | Using the ``monitor'' line given below, you can observe the behavior | ||
482 | of your own peer's DHT with respect to the specified KEY: | ||
483 | |||
484 | @example | ||
485 | # start gnunet with all default services: | ||
486 | $ gnunet-arm -c ~/peer1.conf -s | ||
487 | # start DHT service: | ||
488 | $ gnunet-arm -c ~/peer1.conf -i dht | ||
489 | $ cd ~/gnunet/src/dht; | ||
490 | $ ./gnunet-dht-monitor -c ~/peer1.conf -k KEY | ||
491 | @end example | ||
492 | |||
493 | @noindent | ||
494 | Now open a separate terminal and change again to | ||
495 | the @file{gnunet/src/dht} directory: | ||
496 | |||
497 | @example | ||
498 | $ cd ~/gnunet/src/dht | ||
499 | # put VALUE under KEY in the DHT: | ||
500 | $ ./gnunet-dht-put -c ~/peer1.conf -k KEY -d VALUE | ||
501 | # get key KEY from the DHT: | ||
502 | $ ./gnunet/src/dht/gnunet-dht-get -c ~/peer1.conf -k KEY | ||
503 | # print statistics about current GNUnet state: | ||
504 | $ gnunet-statistics -c ~/peer1.conf | ||
505 | # print statistics about DHT service: | ||
506 | $ gnunet-statistics -c ~/peer1.conf -s dht | ||
507 | @end example | ||
508 | |||
509 | @node Starting Two Peers by Hand | ||
510 | @section Starting Two Peers by Hand | ||
511 | |||
512 | This section describes how to start two peers on the same machine by hand. | ||
513 | The process is rather painful, but the description is somewhat | ||
514 | instructive. In practice, you might prefer the automated method | ||
515 | (@pxref{Starting Peers Using the Testbed Service}). | ||
516 | |||
517 | @menu | ||
518 | * Setup a second peer:: | ||
519 | * Start the second peer and connect the peers:: | ||
520 | * How to connect manually:: | ||
521 | @end menu | ||
522 | |||
523 | @node Setup a second peer | ||
524 | @subsection Setup a second peer | ||
525 | We will now start a second peer on your machine. | ||
526 | For the second peer, you will need to manually create a modified | ||
527 | configuration file to avoid conflicts with ports and directories. | ||
528 | A peers configuration file is by default located | ||
529 | in @file{~/.gnunet/gnunet.conf}. This file is typically very short | ||
530 | or even empty as only the differences to the defaults need to be | ||
531 | specified. The defaults are located in many files in the | ||
532 | @file{$PREFIX/share/gnunet/config.d} directory. | ||
533 | |||
534 | To configure the second peer, use the files | ||
535 | @file{$PREFIX/share/gnunet/config.d} as a template for your main | ||
536 | configuration file: | ||
537 | |||
538 | @example | ||
539 | $ cat $PREFIX/share/gnunet/config.d/*.conf > peer2.conf | ||
540 | @end example | ||
541 | |||
542 | @noindent | ||
543 | Now you have to edit @file{peer2.conf} and change: | ||
544 | |||
545 | @itemize | ||
546 | @item @code{GNUNET\_TEST\_HOME} under @code{PATHS} | ||
547 | @item Every (uncommented) value for ``@code{PORT}'' (add 10000) in any | ||
548 | section (the option may be commented out if @code{PORT} is | ||
549 | prefixed by "\#", in this case, UNIX domain sockets are used | ||
550 | and the PORT option does not need to be touched) | ||
551 | @item Every value for ``@code{UNIXPATH}'' in any section | ||
552 | (e.g. by adding a "-p2" suffix) | ||
553 | @end itemize | ||
554 | |||
555 | to a fresh, unique value. Make sure that the PORT numbers stay | ||
556 | below 65536. From now on, whenever you interact with the second peer, | ||
557 | you need to specify @command{-c peer2.conf} as an additional | ||
558 | command line argument. | ||
559 | |||
560 | Now, generate the 2nd peer's private key: | ||
561 | |||
562 | @example | ||
563 | $ gnunet-peerinfo -s -c peer2.conf | ||
564 | @end example | ||
565 | |||
566 | @noindent | ||
567 | This may take a while, generate entropy using your keyboard or mouse | ||
568 | as needed. Also, make sure the output is different from the | ||
569 | gnunet-peerinfo output for the first peer (otherwise you made an | ||
570 | error in the configuration). | ||
571 | |||
572 | @node Start the second peer and connect the peers | ||
573 | @subsection Start the second peer and connect the peers | ||
574 | |||
575 | Then, you can start a second peer using: | ||
576 | |||
577 | @example | ||
578 | $ gnunet-arm -c peer2.conf -s | ||
579 | $ gnunet-arm -c peer2.conf -i dht | ||
580 | $ ~/gnunet/src/dht/gnunet-dht-put -c peer2.conf -k KEY -d VALUE | ||
581 | $ ~/gnunet/src/dht/gnunet-dht-get -c peer2.conf -k KEY | ||
582 | @end example | ||
583 | |||
584 | If you want the two peers to connect, you have multiple options: | ||
585 | |||
586 | @itemize | ||
587 | @item UDP neighbour discovery (automatic) | ||
588 | @item Setup a bootstrap server | ||
589 | @item Connect manually | ||
590 | @end itemize | ||
591 | |||
592 | To setup peer 1 as bootstrapping server change the configuration of | ||
593 | the first one to be a hostlist server by adding the following lines to | ||
594 | @file{peer1.conf} to enable bootstrapping server: | ||
595 | |||
596 | @example | ||
597 | [hostlist] | ||
598 | OPTIONS = -p | ||
599 | @end example | ||
600 | |||
601 | @noindent | ||
602 | Then change @file{peer2.conf} and replace the ``@code{SERVERS}'' | ||
603 | line in the ``@code{[hostlist]}'' section with | ||
604 | ``@code{http://localhost:8080/}''. Restart both peers using: | ||
605 | |||
606 | @example | ||
607 | # stop first peer | ||
608 | $ gnunet-arm -c peer1.conf -e | ||
609 | # start first peer | ||
610 | $ gnunet-arm -c peer1.conf -s | ||
611 | # start second peer | ||
612 | $ gnunet-arm -c peer2.conf -s | ||
613 | @end example | ||
614 | |||
615 | @noindent | ||
616 | Note that if you start your peers without changing these settings, they | ||
617 | will use the ``global'' hostlist servers of the GNUnet P2P network and | ||
618 | likely connect to those peers. At that point, debugging might become | ||
619 | tricky as you're going to be connected to many more peers and would | ||
620 | likely observe traffic and behaviors that are not explicitly controlled | ||
621 | by you. | ||
622 | |||
623 | @node How to connect manually | ||
624 | @subsection How to connect manually | ||
625 | |||
626 | If you want to use the @code{peerinfo} tool to connect your | ||
627 | peers, you should: | ||
628 | |||
629 | @itemize | ||
630 | @item Set @code{FORCESTART = NO} in section @code{hostlist} | ||
631 | (to not connect to the global GNUnet) | ||
632 | @item Start both peers running @command{gnunet-arm -c peer1.conf -s} | ||
633 | and @command{gnunet-arm -c peer2.conf -s} | ||
634 | @item Get @code{HELLO} message of the first peer running | ||
635 | @command{gnunet-peerinfo -c peer1.conf -g} | ||
636 | @item Give the output to the second peer by running | ||
637 | @command{gnunet-peerinfo -c peer2.conf -p '<output>'} | ||
638 | @end itemize | ||
639 | |||
640 | Check that they are connected using @command{gnunet-core -c peer1.conf}, | ||
641 | which should give you the other peer's peer identity: | ||
642 | |||
643 | @example | ||
644 | $ gnunet-core -c peer1.conf | ||
645 | Peer `9TVUCS8P5A7ILLBGO6 [...shortened...] 1KNBJ4NGCHP3JPVULDG' | ||
646 | @end example | ||
647 | |||
648 | @node Starting Peers Using the Testbed Service | ||
649 | @section Starting Peers Using the Testbed Service | ||
650 | @c \label{sec:testbed} | ||
651 | |||
652 | GNUnet's testbed service is used for testing scenarios where | ||
653 | a number of peers are to be started. The testbed can manage peers | ||
654 | on a single host or on multiple hosts in a distributed fashion. | ||
655 | On a single affordable computer, it should be possible to run | ||
656 | around tens of peers without drastically increasing the load on the | ||
657 | system. | ||
658 | |||
659 | The testbed service can be access through its API | ||
660 | @file{include/gnunet\_testbed\_service.h}. The API provides many | ||
661 | routines for managing a group of peers. It also provides a helper | ||
662 | function @code{GNUNET\_TESTBED\_test\_run()} to quickly setup a | ||
663 | minimalistic testing environment on a single host. | ||
664 | |||
665 | This function takes a configuration file which will be used as a | ||
666 | template configuration for the peers. The testbed takes care of | ||
667 | modifying relevant options in the peers' configuration such as | ||
668 | @code{SERVICEHOME}, @code{PORT}, @code{UNIXPATH} to unique values | ||
669 | so that peers run without running into conflicts. It also checks | ||
670 | and assigns the ports in configurations only if they are free. | ||
671 | |||
672 | Additionally, the testbed service also reads its options from the | ||
673 | same configuration file. Various available options and details | ||
674 | about them can be found in the testbed default configuration file | ||
675 | @file{src/testbed/testbed.conf}. | ||
676 | |||
677 | With the testbed API, a sample test case can be structured as follows: | ||
678 | |||
679 | @example | ||
680 | @verbatiminclude testbed_test.c | ||
681 | @end example | ||
682 | |||
683 | @noindent | ||
684 | The source code for the above listing can be found at | ||
685 | @uref{https://gnunet.org/git/gnunet.git/tree/doc/ | ||
686 | documentation/testbed_test.c} | ||
687 | or in the @file{doc/documentation/} folder of your repository check-out. | ||
688 | After installing GNUnet, the above source code can be compiled as: | ||
689 | |||
690 | @example | ||
691 | $ export CPPFLAGS="-I/path/to/gnunet/headers" | ||
692 | $ export LDFLAGS="-L/path/to/gnunet/libraries" | ||
693 | $ gcc $CPPFLAGS $LDFLAGS -o testbed-test testbed_test.c \ | ||
694 | -lgnunettestbed -lgnunetdht -lgnunetutil | ||
695 | # Generate (empty) configuration | ||
696 | $ touch template.conf | ||
697 | # run it (press CTRL-C to stop) | ||
698 | $ ./testbed-test | ||
699 | @end example | ||
700 | |||
701 | @noindent | ||
702 | The @code{CPPFLAGS} and @code{LDFLAGS} are necessary if GNUnet | ||
703 | is installed into a different directory other than @file{/usr/local}. | ||
704 | |||
705 | All of testbed API's peer management functions treat management | ||
706 | actions as operations and return operation handles. It is expected | ||
707 | that the operations begin immediately, but they may get delayed (to | ||
708 | balance out load on the system). The program using the API then has | ||
709 | to take care of marking the operation as ``done'' so that its | ||
710 | associated resources can be freed immediately and other waiting | ||
711 | operations can be executed. Operations will be canceled if they are | ||
712 | marked as ``done'' before their completion. | ||
713 | |||
714 | An operation is treated as completed when it succeeds or fails. | ||
715 | Completion of an operation is either conveyed as events through | ||
716 | @dfn{controller event callback} or through respective | ||
717 | @dfn{operation completion callbacks}. | ||
718 | In functions which support completion notification | ||
719 | through both controller event callback and operation | ||
720 | completion callback, first the controller event callback will be | ||
721 | called. If the operation is not marked as done in that callback | ||
722 | or if the callback is given as NULL when creating the operation, | ||
723 | the operation completion callback will be called. The API | ||
724 | documentation shows which event are to be expected in the | ||
725 | controller event notifications. It also documents any exceptional | ||
726 | behaviour. | ||
727 | |||
728 | Once the peers are started, test cases often need to connect | ||
729 | some of the peers' services. Normally, opening a connect to | ||
730 | a peer's service requires the peer's configuration. While using | ||
731 | testbed, the testbed automatically generates per-peer configuration. | ||
732 | Accessing those configurations directly through file system is | ||
733 | discouraged as their locations are dynamically created and will be | ||
734 | different among various runs of testbed. To make access to these | ||
735 | configurations easy, testbed API provides the function | ||
736 | @code{GNUNET\_TESTBED\_service\_connect()}. This function fetches | ||
737 | the configuration of a given peer and calls the @dfn{Connect Adapter}. | ||
738 | In the example code, it is the @code{dht\_ca}. A connect adapter is | ||
739 | expected to open the connection to the needed service by using the | ||
740 | provided configuration and return the created service connection handle. | ||
741 | Successful connection to the needed service is signaled through | ||
742 | @code{service\_connect\_comp\_cb}. | ||
743 | |||
744 | A dual to connect adapter is the @dfn{Disconnect Adapter}. This callback | ||
745 | is called after the connect adapter has been called when the operation | ||
746 | from @code{GNUNET\_TESTBED\_service\_connect()} is marked as ``done''. | ||
747 | It has to disconnect from the service with the provided service | ||
748 | handle (@code{op\_result}). | ||
749 | |||
750 | Exercise: Find out how many peers you can run on your system. | ||
751 | |||
752 | Exercise: Find out how to create a 2D torus topology by changing the | ||
753 | options in the configuration file. | ||
754 | @xref{Supported Topologies, The GNUnet Reference Documentation ,, gnunet, The GNUnet Reference Documentation}, | ||
755 | then use the DHT API to store and retrieve values in the network. | ||
756 | |||
757 | @node Developing Applications | ||
758 | @chapter Developing Applications | ||
759 | |||
760 | @menu | ||
761 | * gnunet-ext:: | ||
762 | * Adapting the Template:: | ||
763 | * Writing a Client Application:: | ||
764 | * Writing a Service:: | ||
765 | * Interacting directly with other Peers using the CORE Service:: | ||
766 | * Storing peer-specific data using the PEERSTORE service:: | ||
767 | * Using the DHT:: | ||
768 | * Debugging with gnunet-arm:: | ||
769 | @end menu | ||
770 | |||
771 | @node gnunet-ext | ||
772 | @section gnunet-ext | ||
773 | To develop a new peer-to-peer application or to extend GNUnet we provide | ||
774 | a template build system for writing GNUnet extensions in C. It can be | ||
775 | obtained as follows: | ||
776 | |||
777 | @example | ||
778 | $ git clone https://gnunet.org/git/gnunet-ext | ||
779 | $ cd gnunet-ext/ | ||
780 | $ ./bootstrap | ||
781 | $ ./configure --prefix=$PREFIX --with-gnunet=$PREFIX | ||
782 | $ make | ||
783 | $ make install | ||
784 | $ make check | ||
785 | @end example | ||
786 | |||
787 | @noindent | ||
788 | The GNUnet ext template includes examples and a working buildsystem | ||
789 | for a new GNUnet service. A common GNUnet service consists of the | ||
790 | following parts which will be discussed in detail in the remainder | ||
791 | of this document. The functionality of a GNUnet service is implemented in: | ||
792 | |||
793 | @itemize | ||
794 | @item the GNUnet service (gnunet-ext/src/ext/gnunet-service-ext.c) | ||
795 | @item the client API (gnunet-ext/src/ext/ext_api.c) | ||
796 | @item the client application using the service API | ||
797 | (gnunet-ext/src/ext/gnunet-ext.c) | ||
798 | @end itemize | ||
799 | |||
800 | The interfaces for these entities are defined in: | ||
801 | |||
802 | @itemize | ||
803 | @item client API interface (gnunet-ext/src/ext/ext.h) | ||
804 | @item the service interface (gnunet-ext/src/include/gnunet_service_SERVICE.h) | ||
805 | @item the P2P protocol (gnunet-ext/src/include/gnunet_protocols_ext.h) | ||
806 | @end itemize | ||
807 | |||
808 | |||
809 | In addition the ext systems provides: | ||
810 | |||
811 | @itemize | ||
812 | @item a test testing the API (gnunet-ext/src/ext/test_ext_api.c) | ||
813 | @item a configuration template for the service | ||
814 | (gnunet-ext/src/ext/ext.conf.in) | ||
815 | @end itemize | ||
816 | |||
817 | @node Adapting the Template | ||
818 | @section Adapting the Template | ||
819 | |||
820 | The first step for writing any extension with a new service is to | ||
821 | ensure that the @file{ext.conf.in} file contains entries for the | ||
822 | @code{UNIXPATH}, @code{PORT} and @code{BINARY} for the service in a | ||
823 | section named after the service. | ||
824 | |||
825 | If you want to adapt the template rename the @file{ext.conf.in} to | ||
826 | match your services name, you have to modify the @code{AC\_OUTPUT} | ||
827 | section in @file{configure.ac} in the @file{gnunet-ext} root. | ||
828 | |||
829 | @node Writing a Client Application | ||
830 | @section Writing a Client Application | ||
831 | |||
832 | When writing any client application (for example, a command-line | ||
833 | tool), the basic structure is to start with the | ||
834 | @code{GNUNET\_PROGRAM\_run} function. This function will parse | ||
835 | command-line options, setup the scheduler and then invoke the | ||
836 | @code{run} function (with the remaining non-option arguments) | ||
837 | and a handle to the parsed configuration (and the configuration | ||
838 | file name that was used, which is typically not needed): | ||
839 | |||
840 | @example | ||
841 | @verbatiminclude tutorial-examples/001.c | ||
842 | @end example | ||
843 | |||
844 | @menu | ||
845 | * Handling command-line options:: | ||
846 | * Writing a Client Library:: | ||
847 | * Writing a user interface:: | ||
848 | @end menu | ||
849 | |||
850 | @node Handling command-line options | ||
851 | @subsection Handling command-line options | ||
852 | |||
853 | Options can then be added easily by adding global variables and | ||
854 | expanding the @code{options} array. For example, the following would | ||
855 | add a string-option and a binary flag (defaulting to @code{NULL} and | ||
856 | @code{GNUNET\_NO} respectively): | ||
857 | |||
858 | @example | ||
859 | @verbatiminclude tutorial-examples/002.c | ||
860 | @end example | ||
861 | |||
862 | Issues such as displaying some helpful text describing options using | ||
863 | the @code{--help} argument and error handling are taken care of when | ||
864 | using this approach. Other @code{GNUNET\_GETOPT\_}-functions can be used | ||
865 | to obtain integer value options, increment counters, etc. You can | ||
866 | even write custom option parsers for special circumstances not covered | ||
867 | by the available handlers. To check if an argument was specified by the | ||
868 | user you initialize the variable with a specific value (e.g. NULL for | ||
869 | a string and GNUNET\_SYSERR for a integer) and check after parsing | ||
870 | happened if the values were modified. | ||
871 | |||
872 | Inside the @code{run} method, the program would perform the | ||
873 | application-specific logic, which typically involves initializing and | ||
874 | using some client library to interact with the service. The client | ||
875 | library is supposed to implement the IPC whereas the service provides | ||
876 | more persistent P2P functions. | ||
877 | |||
878 | Exercise: Add a few command-line options and print them inside | ||
879 | of @code{run}. What happens if the user gives invalid arguments? | ||
880 | |||
881 | @node Writing a Client Library | ||
882 | @subsection Writing a Client Library | ||
883 | |||
884 | The first and most important step in writing a client library is to | ||
885 | decide on an API for the library. Typical API calls include | ||
886 | connecting to the service, performing application-specific requests | ||
887 | and cleaning up. Many examples for such service APIs can be found | ||
888 | in the @file{gnunet/src/include/gnunet\_*\_service.h} files. | ||
889 | |||
890 | Then, a client-service protocol needs to be designed. This typically | ||
891 | involves defining various message formats in a header that will be | ||
892 | included by both the service and the client library (but is otherwise | ||
893 | not shared and hence located within the service's directory and not | ||
894 | installed by @command{make install}). Each message must start with a | ||
895 | @code{struct GNUNET\_MessageHeader} and must be shorter than 64k. By | ||
896 | convention, all fields in IPC (and P2P) messages must be in big-endian | ||
897 | format (and thus should be read using @code{ntohl} and similar | ||
898 | functions and written using @code{htonl} and similar functions). | ||
899 | Unique message types must be defined for each message struct in the | ||
900 | @file{gnunet\_protocols.h} header (or an extension-specific include | ||
901 | file). | ||
902 | |||
903 | @menu | ||
904 | * Connecting to the Service:: | ||
905 | * Sending messages:: | ||
906 | * Receiving Replies from the Service:: | ||
907 | @end menu | ||
908 | |||
909 | @node Connecting to the Service | ||
910 | @subsubsection Connecting to the Service | ||
911 | |||
912 | Before a client library can implement the application-specific protocol | ||
913 | with the service, a connection must be created: | ||
914 | |||
915 | @example | ||
916 | @verbatiminclude tutorial-examples/003.c | ||
917 | @end example | ||
918 | |||
919 | @noindent | ||
920 | As a result a @code{GNUNET\_MQ\_Handle} is returned | ||
921 | which can to used henceforth to transmit messages to the service. | ||
922 | The complete MQ API can be found in @file{gnunet\_mq\_lib.h}. | ||
923 | The @code{hanlders} array in the example above is incomplete. | ||
924 | Here is where you will define which messages you expect to | ||
925 | receive from the service, and which functions handle them. | ||
926 | The @code{error\_cb} is a function that is to be called whenever | ||
927 | there are errors communicating with the service. | ||
928 | |||
929 | @node Sending messages | ||
930 | @subsubsection Sending messages | ||
931 | |||
932 | In GNUnet, messages are always sent beginning with a | ||
933 | @code{struct GNUNET\_MessageHeader} in big endian format. | ||
934 | This header defines the size and the type of the | ||
935 | message, the payload follows after this header. | ||
936 | |||
937 | @example | ||
938 | @verbatiminclude tutorial-examples/004.c | ||
939 | @end example | ||
940 | |||
941 | @noindent | ||
942 | Existing message types are defined in @file{gnunet\_protocols.h}. | ||
943 | A common way to create a message is with an envelope: | ||
944 | |||
945 | @example | ||
946 | @verbatiminclude tutorial-examples/005.c | ||
947 | @end example | ||
948 | |||
949 | @noindent | ||
950 | Exercise: Define a message struct that includes a 32-bit | ||
951 | unsigned integer in addition to the standard GNUnet MessageHeader. | ||
952 | Add a C struct and define a fresh protocol number for your message. | ||
953 | Protocol numbers in gnunet-ext are defined | ||
954 | in @file{gnunet-ext/src/include/gnunet_protocols_ext.h} | ||
955 | |||
956 | Exercise: Find out how you can determine the number of messages | ||
957 | in a message queue. | ||
958 | |||
959 | Exercise: Find out how you can determine when a message you | ||
960 | have queued was actually transmitted. | ||
961 | |||
962 | Exercise: Define a helper function to transmit a 32-bit | ||
963 | unsigned integer (as payload) to a service using some given client | ||
964 | handle. | ||
965 | |||
966 | @node Receiving Replies from the Service | ||
967 | @subsubsection Receiving Replies from the Service | ||
968 | |||
969 | Clients can receive messages from the service using the handlers | ||
970 | specified in the @code{handlers} array we specified when connecting | ||
971 | to the service. Entries in the the array are usually created using | ||
972 | one of two macros, depending on whether the message is fixed size | ||
973 | or variable size. Variable size messages are managed using two | ||
974 | callbacks, one to check that the message is well-formed, the other | ||
975 | to actually process the message. Fixed size messages are fully | ||
976 | checked by the MQ-logic, and thus only need to provide the handler | ||
977 | to process the message. Note that the prefixes @code{check\_} | ||
978 | and @code{handle\_} are mandatory. | ||
979 | |||
980 | @example | ||
981 | @verbatiminclude tutorial-examples/006.c | ||
982 | @end example | ||
983 | |||
984 | @noindent | ||
985 | Exercise: Expand your helper function to receive a response message | ||
986 | (for example, containing just the @code{struct GNUnet MessageHeader} | ||
987 | without any payload). Upon receiving the service's response, you | ||
988 | should call a callback provided to your helper function's API. | ||
989 | |||
990 | Exercise: Figure out where you can pass values to the | ||
991 | closures (@code{cls}). | ||
992 | |||
993 | @node Writing a user interface | ||
994 | @subsection Writing a user interface | ||
995 | |||
996 | Given a client library, all it takes to access a service now is to | ||
997 | combine calls to the client library with parsing command-line | ||
998 | options. | ||
999 | |||
1000 | Exercise: Call your client API from your @code{run()} method in your | ||
1001 | client application to send a request to the service. For example, | ||
1002 | send a 32-bit integer value based on a number given at the | ||
1003 | command-line to the service. | ||
1004 | |||
1005 | @node Writing a Service | ||
1006 | @section Writing a Service | ||
1007 | |||
1008 | Before you can test the client you've written so far, you'll | ||
1009 | need to also implement the corresponding service. | ||
1010 | |||
1011 | @menu | ||
1012 | * Code Placement:: | ||
1013 | * Starting a Service:: | ||
1014 | @end menu | ||
1015 | |||
1016 | @node Code Placement | ||
1017 | @subsection Code Placement | ||
1018 | |||
1019 | New services are placed in their own subdirectory under | ||
1020 | @file{gnunet/src}. This subdirectory should contain the API | ||
1021 | implementation file @file{SERVICE\_api.c}, the description of | ||
1022 | the client-service protocol @file{SERVICE.h} and P2P protocol | ||
1023 | @file{SERVICE\_protocol.h}, the implementation of the service itself | ||
1024 | @file{gnunet-service-SERVICE.h} and several files for tests, | ||
1025 | including test code and configuration files. | ||
1026 | |||
1027 | @node Starting a Service | ||
1028 | @subsection Starting a Service | ||
1029 | |||
1030 | The key API definition for creating a service is the | ||
1031 | @code{GNUNET\_SERVICE\_MAIN} macro: | ||
1032 | |||
1033 | @example | ||
1034 | @verbatiminclude tutorial-examples/007.c | ||
1035 | @end example | ||
1036 | |||
1037 | @noindent | ||
1038 | In addition to the service name and flags, the macro takes three | ||
1039 | functions, typically called @code{run}, @code{client\_connect\_cb} and | ||
1040 | @code{client\_disconnect\_cb} as well as an array of message handlers | ||
1041 | that will be called for incoming messages from clients. | ||
1042 | |||
1043 | A minimal version of the three central service funtions would look | ||
1044 | like this: | ||
1045 | |||
1046 | @example | ||
1047 | @verbatiminclude tutorial-examples/008.c | ||
1048 | @end example | ||
1049 | |||
1050 | @noindent | ||
1051 | Exercise: Write a stub service that processes no messages at all | ||
1052 | in your code. Create a default configuration for it, integrate it | ||
1053 | with the build system and start the service from | ||
1054 | @command{gnunet-service-arm} using @command{gnunet-arm -i NAME}. | ||
1055 | |||
1056 | Exercise: Figure out how to set the closure (@code{cls}) for handlers | ||
1057 | of a service. | ||
1058 | |||
1059 | Exercise: Figure out how to send messages from the service back to the | ||
1060 | client. | ||
1061 | |||
1062 | Each handler function in the service @b{must} eventually (possibly in some | ||
1063 | asynchronous continuation) call | ||
1064 | @code{GNUNET\_SERVICE\_client\_continue()}. Only after this call | ||
1065 | additional messages from the same client may | ||
1066 | be processed. This way, the service can throttle processing messages | ||
1067 | from the same client. | ||
1068 | |||
1069 | Exercise: Change the service to ``handle'' the message from your | ||
1070 | client (for now, by printing a message). What happens if you | ||
1071 | forget to call @code{GNUNET\_SERVICE\_client\_continue()}? | ||
1072 | |||
1073 | @node Interacting directly with other Peers using the CORE Service | ||
1074 | @section Interacting directly with other Peers using the CORE Service | ||
1075 | |||
1076 | FIXME: This section still needs to be updated to the lastest API! | ||
1077 | |||
1078 | One of the most important services in GNUnet is the @code{CORE} service | ||
1079 | managing connections between peers and handling encryption between peers. | ||
1080 | |||
1081 | One of the first things any service that extends the P2P protocol | ||
1082 | typically does is connect to the @code{CORE} service using: | ||
1083 | |||
1084 | @example | ||
1085 | @verbatiminclude tutorial-examples/009.c | ||
1086 | @end example | ||
1087 | |||
1088 | @menu | ||
1089 | * New P2P connections:: | ||
1090 | * Receiving P2P Messages:: | ||
1091 | * Sending P2P Messages:: | ||
1092 | * End of P2P connections:: | ||
1093 | @end menu | ||
1094 | |||
1095 | @node New P2P connections | ||
1096 | @subsection New P2P connections | ||
1097 | |||
1098 | Before any traffic with a different peer can be exchanged, the peer must | ||
1099 | be known to the service. This is notified by the @code{CORE} | ||
1100 | @code{connects} callback, which communicates the identity of the new | ||
1101 | peer to the service: | ||
1102 | |||
1103 | @example | ||
1104 | @verbatiminclude tutorial-examples/010.c | ||
1105 | @end example | ||
1106 | |||
1107 | @noindent | ||
1108 | Note that whatever you return from @code{connects} is given as the | ||
1109 | @code{cls} argument to the message handlers for messages from | ||
1110 | the respective peer. | ||
1111 | |||
1112 | Exercise: Create a service that connects to the @code{CORE}. Then | ||
1113 | start (and connect) two peers and print a message once your connect | ||
1114 | callback is invoked. | ||
1115 | |||
1116 | @node Receiving P2P Messages | ||
1117 | @subsection Receiving P2P Messages | ||
1118 | |||
1119 | To receive messages from @code{CORE}, you pass the desired | ||
1120 | @code{handlers} to the @code{GNUNET\_CORE\_connect()} function, | ||
1121 | just as we showed for services. | ||
1122 | |||
1123 | It is your responsibility to process messages fast enough or | ||
1124 | to implement flow control. If an application does not process | ||
1125 | CORE messages fast enough, CORE will randomly drop messages | ||
1126 | to not keep a very long queue in memory. | ||
1127 | |||
1128 | Exercise: Start one peer with a new service that has a message | ||
1129 | handler and start a second peer that only has your ``old'' service | ||
1130 | without message handlers. Which ``connect'' handlers are invoked when | ||
1131 | the two peers are connected? Why? | ||
1132 | |||
1133 | @node Sending P2P Messages | ||
1134 | @subsection Sending P2P Messages | ||
1135 | |||
1136 | You can transmit messages to other peers using the @code{mq} you were | ||
1137 | given during the @code{connect} callback. Note that the @code{mq} | ||
1138 | automatically is released upon @code{disconnect} and that you must | ||
1139 | not use it afterwards. | ||
1140 | |||
1141 | It is your responsibility to not over-fill the message queue, GNUnet | ||
1142 | will send the messages roughly in the order given as soon as possible. | ||
1143 | |||
1144 | Exercise: Write a service that upon connect sends messages as | ||
1145 | fast as possible to the other peer (the other peer should run a | ||
1146 | service that ``processes'' those messages). How fast is the | ||
1147 | transmission? Count using the STATISTICS service on both ends. Are | ||
1148 | messages lost? How can you transmit messages faster? What happens if | ||
1149 | you stop the peer that is receiving your messages? | ||
1150 | |||
1151 | @node End of P2P connections | ||
1152 | @subsection End of P2P connections | ||
1153 | |||
1154 | If a message handler returns @code{GNUNET\_SYSERR}, the remote | ||
1155 | peer shuts down or there is an unrecoverable network | ||
1156 | disconnection, CORE notifies the service that the peer disconnected. | ||
1157 | After this notification no more messages will be received from the | ||
1158 | peer and the service is no longer allowed to send messages to the peer. | ||
1159 | The disconnect callback looks like the following: | ||
1160 | |||
1161 | @example | ||
1162 | @verbatiminclude tutorial-examples/011.c | ||
1163 | @end example | ||
1164 | |||
1165 | @noindent | ||
1166 | Exercise: Fix your service to handle peer disconnects. | ||
1167 | |||
1168 | @node Storing peer-specific data using the PEERSTORE service | ||
1169 | @section Storing peer-specific data using the PEERSTORE service | ||
1170 | |||
1171 | GNUnet's PEERSTORE service offers a persistorage for arbitrary | ||
1172 | peer-specific data. Other GNUnet services can use the PEERSTORE | ||
1173 | to store, retrieve and monitor data records. Each data record | ||
1174 | stored with PEERSTORE contains the following fields: | ||
1175 | |||
1176 | @itemize | ||
1177 | @item subsystem: Name of the subsystem responsible for the record. | ||
1178 | @item peerid: Identity of the peer this record is related to. | ||
1179 | @item key: a key string identifying the record. | ||
1180 | @item value: binary record value. | ||
1181 | @item expiry: record expiry date. | ||
1182 | @end itemize | ||
1183 | |||
1184 | The first step is to start a connection to the PEERSTORE service: | ||
1185 | @example | ||
1186 | @verbatiminclude tutorial-examples/012.c | ||
1187 | @end example | ||
1188 | |||
1189 | The service handle @code{peerstore_handle} will be needed for | ||
1190 | all subsequent PEERSTORE operations. | ||
1191 | |||
1192 | @menu | ||
1193 | * Storing records:: | ||
1194 | * Retrieving records:: | ||
1195 | * Monitoring records:: | ||
1196 | * Disconnecting from PEERSTORE:: | ||
1197 | @end menu | ||
1198 | |||
1199 | @node Storing records | ||
1200 | @subsection Storing records | ||
1201 | |||
1202 | To store a new record, use the following function: | ||
1203 | |||
1204 | @example | ||
1205 | @verbatiminclude tutorial-examples/013.c | ||
1206 | @end example | ||
1207 | |||
1208 | @noindent | ||
1209 | The @code{options} parameter can either be | ||
1210 | @code{GNUNET_PEERSTORE_STOREOPTION_MULTIPLE} which means that multiple | ||
1211 | values can be stored under the same key combination | ||
1212 | (subsystem, peerid, key), or @code{GNUNET_PEERSTORE_STOREOPTION_REPLACE} | ||
1213 | which means that PEERSTORE will replace any existing values under the | ||
1214 | given key combination (subsystem, peerid, key) with the new given value. | ||
1215 | |||
1216 | The continuation function @code{cont} will be called after the store | ||
1217 | request is successfully sent to the PEERSTORE service. This does not | ||
1218 | guarantee that the record is successfully stored, only that it was | ||
1219 | received by the service. | ||
1220 | |||
1221 | The @code{GNUNET_PEERSTORE_store} function returns a handle to the store | ||
1222 | operation. This handle can be used to cancel the store operation only | ||
1223 | before the continuation function is called: | ||
1224 | |||
1225 | @example | ||
1226 | @verbatiminclude tutorial-examples/013.1.c | ||
1227 | @end example | ||
1228 | |||
1229 | @node Retrieving records | ||
1230 | @subsection Retrieving records | ||
1231 | |||
1232 | To retrieve stored records, use the following function: | ||
1233 | |||
1234 | @example | ||
1235 | @verbatiminclude tutorial-examples/014.c | ||
1236 | @end example | ||
1237 | |||
1238 | @noindent | ||
1239 | The values of @code{peer} and @code{key} can be @code{NULL}. This | ||
1240 | allows the iteration over values stored under any of the following | ||
1241 | key combinations: | ||
1242 | |||
1243 | @itemize | ||
1244 | @item (subsystem) | ||
1245 | @item (subsystem, peerid) | ||
1246 | @item (subsystem, key) | ||
1247 | @item (subsystem, peerid, key) | ||
1248 | @end itemize | ||
1249 | |||
1250 | The @code{callback} function will be called once with each retrieved | ||
1251 | record and once more with a @code{NULL} record to signal the end of | ||
1252 | results. | ||
1253 | |||
1254 | The @code{GNUNET_PEERSTORE_iterate} function returns a handle to the | ||
1255 | iterate operation. This handle can be used to cancel the iterate | ||
1256 | operation only before the callback function is called with a | ||
1257 | @code{NULL} record. | ||
1258 | |||
1259 | @node Monitoring records | ||
1260 | @subsection Monitoring records | ||
1261 | |||
1262 | PEERSTORE offers the functionality of monitoring for new records | ||
1263 | stored under a specific key combination (subsystem, peerid, key). | ||
1264 | To start the monitoring, use the following function: | ||
1265 | |||
1266 | @example | ||
1267 | @verbatiminclude tutorial-examples/015.c | ||
1268 | @end example | ||
1269 | |||
1270 | @noindent | ||
1271 | Whenever a new record is stored under the given key combination, | ||
1272 | the @code{callback} function will be called with this new | ||
1273 | record. This will continue until the connection to the PEERSTORE | ||
1274 | service is broken or the watch operation is canceled: | ||
1275 | |||
1276 | @example | ||
1277 | @verbatiminclude tutorial-examples/016.c | ||
1278 | @end example | ||
1279 | |||
1280 | @node Disconnecting from PEERSTORE | ||
1281 | @subsection Disconnecting from PEERSTORE | ||
1282 | |||
1283 | When the connection to the PEERSTORE service is no longer needed, | ||
1284 | disconnect using the following function: | ||
1285 | |||
1286 | @example | ||
1287 | @verbatiminclude tutorial-examples/017.c | ||
1288 | @end example | ||
1289 | |||
1290 | @noindent | ||
1291 | If the @code{sync_first} flag is set to @code{GNUNET_YES}, | ||
1292 | the API will delay the disconnection until all store requests | ||
1293 | are received by the PEERSTORE service. Otherwise, it will | ||
1294 | disconnect immediately. | ||
1295 | |||
1296 | @node Using the DHT | ||
1297 | @section Using the DHT | ||
1298 | |||
1299 | The DHT allows to store data so other peers in the P2P network can | ||
1300 | access it and retrieve data stored by any peers in the network. | ||
1301 | This section will explain how to use the DHT. Of course, the first | ||
1302 | thing to do is to connect to the DHT service: | ||
1303 | |||
1304 | @example | ||
1305 | @verbatiminclude tutorial-examples/018.c | ||
1306 | @end example | ||
1307 | |||
1308 | @noindent | ||
1309 | The second parameter indicates how many requests in parallel to expect. | ||
1310 | It is not a hard limit, but a good approximation will make the DHT more | ||
1311 | efficient. | ||
1312 | |||
1313 | @menu | ||
1314 | * Storing data in the DHT:: | ||
1315 | * Obtaining data from the DHT:: | ||
1316 | * Implementing a block plugin:: | ||
1317 | * Monitoring the DHT:: | ||
1318 | @end menu | ||
1319 | |||
1320 | @node Storing data in the DHT | ||
1321 | @subsection Storing data in the DHT | ||
1322 | Since the DHT is a dynamic environment (peers join and leave frequently) | ||
1323 | the data that we put in the DHT does not stay there indefinitely. It is | ||
1324 | important to ``refresh'' the data periodically by simply storing it | ||
1325 | again, in order to make sure other peers can access it. | ||
1326 | |||
1327 | The put API call offers a callback to signal that the PUT request has been | ||
1328 | sent. This does not guarantee that the data is accessible to others peers, | ||
1329 | or even that is has been stored, only that the service has requested to | ||
1330 | a neighboring peer the retransmission of the PUT request towards its final | ||
1331 | destination. Currently there is no feedback about whether or not the data | ||
1332 | has been sucessfully stored or where it has been stored. In order to | ||
1333 | improve the availablilty of the data and to compensate for possible | ||
1334 | errors, peers leaving and other unfavorable events, just make several | ||
1335 | PUT requests! | ||
1336 | |||
1337 | @example | ||
1338 | @verbatiminclude tutorial-examples/019.c | ||
1339 | @end example | ||
1340 | |||
1341 | @noindent | ||
1342 | Exercise: Store a value in the DHT periodically to make sure it | ||
1343 | is available over time. You might consider using the function | ||
1344 | @code{GNUNET\_SCHEDULER\_add\_delayed} and call | ||
1345 | @code{GNUNET\_DHT\_put} from inside a helper function. | ||
1346 | |||
1347 | @node Obtaining data from the DHT | ||
1348 | @subsection Obtaining data from the DHT | ||
1349 | |||
1350 | As we saw in the previous example, the DHT works in an asynchronous mode. | ||
1351 | Each request to the DHT is executed ``in the background'' and the API | ||
1352 | calls return immediately. In order to receive results from the DHT, the | ||
1353 | API provides a callback. Once started, the request runs in the service, | ||
1354 | the service will try to get as many results as possible (filtering out | ||
1355 | duplicates) until the timeout expires or we explicitly stop the request. | ||
1356 | It is possible to give a ``forever'' timeout with | ||
1357 | @code{GNUNET\_TIME\_UNIT\_FOREVER\_REL}. | ||
1358 | |||
1359 | If we give a route option @code{GNUNET\_DHT\_RO\_RECORD\_ROUTE} | ||
1360 | the callback will get a list of all the peers the data has travelled, | ||
1361 | both on the PUT path and on the GET path. | ||
1362 | |||
1363 | @example | ||
1364 | @verbatiminclude tutorial-examples/020.c | ||
1365 | @end example | ||
1366 | |||
1367 | @noindent | ||
1368 | Exercise: Store a value in the DHT and after a while retrieve it. | ||
1369 | Show the IDs of all the peers the requests have gone through. | ||
1370 | In order to convert a peer ID to a string, use the function | ||
1371 | @code{GNUNET\_i2s}. Pay attention to the route option parameters | ||
1372 | in both calls! | ||
1373 | |||
1374 | @node Implementing a block plugin | ||
1375 | @subsection Implementing a block plugin | ||
1376 | |||
1377 | In order to store data in the DHT, it is necessary to provide a block | ||
1378 | plugin. The DHT uses the block plugin to ensure that only well-formed | ||
1379 | requests and replies are transmitted over the network. | ||
1380 | |||
1381 | The block plugin should be put in a file @file{plugin\_block\_SERVICE.c} | ||
1382 | in the service's respective directory. The | ||
1383 | mandatory functions that need to be implemented for a block plugin are | ||
1384 | described in the following sections. | ||
1385 | |||
1386 | @menu | ||
1387 | * Validating requests and replies:: | ||
1388 | * Deriving a key from a reply:: | ||
1389 | * Initialization of the plugin:: | ||
1390 | * Shutdown of the plugin:: | ||
1391 | * Integration of the plugin with the build system:: | ||
1392 | @end menu | ||
1393 | |||
1394 | @node Validating requests and replies | ||
1395 | @subsubsection Validating requests and replies | ||
1396 | |||
1397 | The evaluate function should validate a reply or a request. It returns | ||
1398 | a @code{GNUNET\_BLOCK\_EvaluationResult}, which is an enumeration. All | ||
1399 | possible answers are in @file{gnunet\_block\_lib.h}. The function will | ||
1400 | be called with a @code{reply\_block} argument of @code{NULL} for | ||
1401 | requests. Note that depending on how @code{evaluate} is called, only | ||
1402 | some of the possible return values are valid. The specific meaning of | ||
1403 | the @code{xquery} argument is application-specific. Applications that | ||
1404 | do not use an extended query should check that the @code{xquery\_size} | ||
1405 | is zero. The block group is typically used to filter duplicate | ||
1406 | replies. | ||
1407 | |||
1408 | @example | ||
1409 | @verbatiminclude tutorial-examples/021.c | ||
1410 | @end example | ||
1411 | |||
1412 | @noindent | ||
1413 | Note that it is mandatory to detect duplicate replies in this function | ||
1414 | and return the respective status code. Duplicate detection is | ||
1415 | typically done using the Bloom filter block group provided by | ||
1416 | @file{libgnunetblockgroup.so}. Failure to do so may cause replies to | ||
1417 | circle in the network. | ||
1418 | |||
1419 | @node Deriving a key from a reply | ||
1420 | @subsubsection Deriving a key from a reply | ||
1421 | |||
1422 | The DHT can operate more efficiently if it is possible to derive a key | ||
1423 | from the value of the corresponding block. The @code{get\_key} | ||
1424 | function is used to obtain the key of a block --- for example, by | ||
1425 | means of hashing. If deriving the key is not possible, the function | ||
1426 | should simply return @code{GNUNET\_SYSERR} (the DHT will still work | ||
1427 | just fine with such blocks). | ||
1428 | |||
1429 | @example | ||
1430 | @verbatiminclude tutorial-examples/022.c | ||
1431 | @end example | ||
1432 | |||
1433 | @node Initialization of the plugin | ||
1434 | @subsubsection Initialization of the plugin | ||
1435 | |||
1436 | The plugin is realized as a shared C library. The library must export | ||
1437 | an initialization function which should initialize the plugin. The | ||
1438 | initialization function specifies what block types the plugin cares | ||
1439 | about and returns a struct with the functions that are to be used for | ||
1440 | validation and obtaining keys (the ones just defined above). | ||
1441 | |||
1442 | @example | ||
1443 | @verbatiminclude tutorial-examples/023.c | ||
1444 | @end example | ||
1445 | |||
1446 | @node Shutdown of the plugin | ||
1447 | @subsubsection Shutdown of the plugin | ||
1448 | |||
1449 | Following GNUnet's general plugin API concept, the plugin must | ||
1450 | export a second function for cleaning up. It usually does very | ||
1451 | little. | ||
1452 | |||
1453 | @example | ||
1454 | @verbatiminclude tutorial-examples/024.c | ||
1455 | @end example | ||
1456 | |||
1457 | @node Integration of the plugin with the build system | ||
1458 | @subsubsection Integration of the plugin with the build system | ||
1459 | |||
1460 | In order to compile the plugin, the @file{Makefile.am} file for the | ||
1461 | service SERVICE should contain a rule similar to this: | ||
1462 | @c Actually this is a Makefile not C. But the whole structure of examples | ||
1463 | @c must be improved. | ||
1464 | |||
1465 | @example | ||
1466 | @verbatiminclude tutorial-examples/025.c | ||
1467 | @end example | ||
1468 | |||
1469 | @noindent | ||
1470 | Exercise: Write a block plugin that accepts all queries | ||
1471 | and all replies but prints information about queries and replies | ||
1472 | when the respective validation hooks are called. | ||
1473 | |||
1474 | @node Monitoring the DHT | ||
1475 | @subsection Monitoring the DHT | ||
1476 | |||
1477 | It is possible to monitor the functioning of the local | ||
1478 | DHT service. When monitoring the DHT, the service will | ||
1479 | alert the monitoring program of any events, both started | ||
1480 | locally or received for routing from another peer. | ||
1481 | The are three different types of events possible: a | ||
1482 | GET request, a PUT request or a response (a reply to a GET). | ||
1483 | |||
1484 | Since the different events have different associated data, | ||
1485 | the API gets 3 different callbacks (one for each message type) | ||
1486 | and optional type and key parameters, to allow for filtering of | ||
1487 | messages. When an event happens, the appropiate callback is | ||
1488 | called with all the information about the event. | ||
1489 | |||
1490 | @example | ||
1491 | @verbatiminclude tutorial-examples/026.c | ||
1492 | @end example | ||
1493 | |||
1494 | @node Debugging with gnunet-arm | ||
1495 | @section Debugging with gnunet-arm | ||
1496 | |||
1497 | Even if services are managed by @command{gnunet-arm}, you can | ||
1498 | start them with @command{gdb} or @command{valgrind}. For | ||
1499 | example, you could add the following lines to your | ||
1500 | configuration file to start the DHT service in a @command{gdb} | ||
1501 | session in a fresh @command{xterm}: | ||
1502 | |||
1503 | @example | ||
1504 | [dht] | ||
1505 | PREFIX=xterm -e gdb --args | ||
1506 | @end example | ||
1507 | |||
1508 | @noindent | ||
1509 | Alternatively, you can stop a service that was started via | ||
1510 | ARM and run it manually: | ||
1511 | |||
1512 | @example | ||
1513 | $ gnunet-arm -k dht | ||
1514 | $ gdb --args gnunet-service-dht -L DEBUG | ||
1515 | $ valgrind gnunet-service-dht -L DEBUG | ||
1516 | @end example | ||
1517 | |||
1518 | @noindent | ||
1519 | Assuming other services are well-written, they will automatically | ||
1520 | re-integrate the restarted service with the peer. | ||
1521 | |||
1522 | GNUnet provides a powerful logging mechanism providing log | ||
1523 | levels @code{ERROR}, @code{WARNING}, @code{INFO} and @code{DEBUG}. | ||
1524 | The current log level is configured using the @code{$GNUNET_FORCE_LOG} | ||
1525 | environmental variable. The @code{DEBUG} level is only available if | ||
1526 | @command{--enable-logging=verbose} was used when running | ||
1527 | @command{configure}. More details about logging can be found under | ||
1528 | @uref{https://gnunet.org/logging}. | ||
1529 | |||
1530 | You should also probably enable the creation of core files, by setting | ||
1531 | @code{ulimit}, and echo'ing @code{1} into | ||
1532 | @file{/proc/sys/kernel/core\_uses\_pid}. Then you can investigate the | ||
1533 | core dumps with @command{gdb}, which is often the fastest method to | ||
1534 | find simple errors. | ||
1535 | |||
1536 | Exercise: Add a memory leak to your service and obtain a trace | ||
1537 | pointing to the leak using @command{valgrind} while running the service | ||
1538 | from @command{gnunet-service-arm}. | ||
1539 | |||
1540 | @bye | ||
diff --git a/doc/documentation/gnunet.texi b/doc/documentation/gnunet.texi new file mode 100644 index 000000000..35eed54b6 --- /dev/null +++ b/doc/documentation/gnunet.texi | |||
@@ -0,0 +1,236 @@ | |||
1 | \input texinfo | ||
2 | @c -*-texinfo-*- | ||
3 | |||
4 | @c %**start of header | ||
5 | @setfilename gnunet.info | ||
6 | @documentencoding UTF-8 | ||
7 | @settitle GNUnet Reference Manual | ||
8 | @exampleindent 2 | ||
9 | @urefbreakstyle before | ||
10 | @c %**end of header | ||
11 | |||
12 | @include version.texi | ||
13 | |||
14 | @c Set Versions which might be used in more than one place: | ||
15 | @set GNUFTP-URL https://ftp.gnu.org/gnu/gnunet | ||
16 | @set PYPI-URL https://pypi.python.org/packages/source | ||
17 | @set GNURL-VERSION-CURRENT 7.55.1 | ||
18 | @set GNUNET-DIST-URL https://gnunet.org/sites/default/files/ | ||
19 | @c @set OPENPGP-SIGNING-KEY-ID | ||
20 | |||
21 | @copying | ||
22 | Copyright @copyright{} 2001-2017 GNUnet e.V. | ||
23 | |||
24 | Permission is granted to copy, distribute and/or modify this document | ||
25 | under the terms of the GNU Free Documentation License, Version 1.3 or | ||
26 | any later version published by the Free Software Foundation; with no | ||
27 | Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A | ||
28 | copy of the license is included in the section entitled ``GNU Free | ||
29 | Documentation License''. | ||
30 | |||
31 | A copy of the license is also available from the Free Software | ||
32 | Foundation Web site at @url{http://www.gnu.org/licenses/fdl.html}. | ||
33 | |||
34 | Alternately, this document is also available under the General | ||
35 | Public License, version 3 or later, as published by the Free Software | ||
36 | Foundation. A copy of the license is included in the section entitled | ||
37 | ``GNU General Public License''. | ||
38 | |||
39 | A copy of the license is also available from the Free Software | ||
40 | Foundation Web site at @url{http://www.gnu.org/licenses/gpl.html}. | ||
41 | @end copying | ||
42 | |||
43 | @c TODO: Improve this and improve https://directory.fsf.org/wiki/Gnunet | ||
44 | |||
45 | @dircategory Networking | ||
46 | @direntry | ||
47 | * GNUnet: (gnunet). Framework for secure peer-to-peer networking | ||
48 | @end direntry | ||
49 | |||
50 | @titlepage | ||
51 | @title GNUnet Reference Manual | ||
52 | @subtitle Installing, configuring, using and contributing to GNUnet | ||
53 | @author The GNUnet Developers | ||
54 | |||
55 | @page | ||
56 | @vskip 0pt plus 1filll | ||
57 | Edition @value{EDITION} @* | ||
58 | @value{UPDATED} @* | ||
59 | |||
60 | @insertcopying | ||
61 | @end titlepage | ||
62 | |||
63 | @summarycontents | ||
64 | @contents | ||
65 | |||
66 | @node Top | ||
67 | @top Introduction | ||
68 | |||
69 | This document is the Reference Manual for GNUnet version @value{VERSION}. | ||
70 | |||
71 | @menu | ||
72 | |||
73 | * Philosophy:: About GNUnet | ||
74 | * Vocabulary:: Vocabulary | ||
75 | * GNUnet Installation Handbook:: How to install GNUnet | ||
76 | * Using GNUnet:: Using GNUnet | ||
77 | * Configuration Handbook:: Configuring GNUnet | ||
78 | * GNUnet Contributors Handbook:: Contributing to GNUnet | ||
79 | * GNUnet Developer Handbook:: Developing GNUnet | ||
80 | * GNU Free Documentation License:: The license of this manual | ||
81 | * GNU General Public License:: The license of this manual | ||
82 | * Concept Index:: Concepts | ||
83 | * Programming Index:: Data types, functions, and variables | ||
84 | |||
85 | @detailmenu | ||
86 | --- The Detailed Node Listing --- | ||
87 | |||
88 | Philosophy | ||
89 | |||
90 | * Design Goals:: | ||
91 | * Security and Privacy:: | ||
92 | * Versatility:: | ||
93 | * Practicality:: | ||
94 | * Key Concepts:: | ||
95 | * Authentication:: | ||
96 | * Accounting to Encourage Resource Sharing:: | ||
97 | * Confidentiality:: | ||
98 | * Anonymity:: | ||
99 | * Deniability:: | ||
100 | * Peer Identities:: | ||
101 | * Zones in the GNU Name System (GNS Zones):: | ||
102 | * Egos:: | ||
103 | * Backup of Identities and Egos:: | ||
104 | * Revocation:: | ||
105 | |||
106 | Vocabulary | ||
107 | |||
108 | * Definitions abbreviations and acronyms:: | ||
109 | * Words and characters:: | ||
110 | * Technical Assumptions:: | ||
111 | |||
112 | GNUnet Installation Handbook | ||
113 | |||
114 | * Dependencies:: | ||
115 | * Pre-installation notes:: | ||
116 | * Generic installation instructions:: | ||
117 | * Build instructions for Ubuntu 12.04 using Git:: | ||
118 | * Build instructions for software builds from source:: | ||
119 | * Build Instructions for Microsoft Windows Platforms:: | ||
120 | * Build instructions for Debian 7.5:: | ||
121 | * Installing GNUnet from Git on Ubuntu 14.4:: | ||
122 | * Build instructions for Debian 8:: | ||
123 | * Outdated build instructions for previous revisions:: | ||
124 | @c * Portable GNUnet:: | ||
125 | * The graphical configuration interface:: | ||
126 | * How to start and stop a GNUnet peer:: | ||
127 | |||
128 | Using GNUnet | ||
129 | |||
130 | * Checking the Installation:: | ||
131 | * First steps - File-sharing:: | ||
132 | * First steps - Using the GNU Name System:: | ||
133 | * First steps - Using GNUnet Conversation:: | ||
134 | * First steps - Using the GNUnet VPN:: | ||
135 | * File-sharing:: | ||
136 | * The GNU Name System:: | ||
137 | * Using the Virtual Public Network:: | ||
138 | |||
139 | Configuration Handbook | ||
140 | |||
141 | GNUnet Contributors Handbook | ||
142 | |||
143 | * Contributing to GNUnet:: | ||
144 | * Licenses of contributions:: | ||
145 | * Copyright Assignment:: | ||
146 | * Contributing to the Reference Manual:: | ||
147 | |||
148 | GNUnet Developer Handbook | ||
149 | |||
150 | * Developer Introduction:: | ||
151 | * Code overview:: | ||
152 | * System Architecture:: | ||
153 | * Subsystem stability:: | ||
154 | * Naming conventions and coding style guide:: | ||
155 | * Build-system:: | ||
156 | * Developing extensions for GNUnet using the gnunet-ext template:: | ||
157 | * Writing testcases:: | ||
158 | * TESTING library:: | ||
159 | * Performance regression analysis with Gauger:: | ||
160 | * TESTBED Subsystem:: | ||
161 | * libgnunetutil:: | ||
162 | * Automatic Restart Manager (ARM):: | ||
163 | * TRANSPORT Subsystem:: | ||
164 | * NAT library:: | ||
165 | * Distance-Vector plugin:: | ||
166 | * SMTP plugin:: | ||
167 | * Bluetooth plugin:: | ||
168 | * WLAN plugin:: | ||
169 | * ATS Subsystem:: | ||
170 | * CORE Subsystem:: | ||
171 | * CADET Subsystem:: | ||
172 | * NSE Subsystem:: | ||
173 | * HOSTLIST Subsystem:: | ||
174 | * IDENTITY Subsystem:: | ||
175 | * NAMESTORE Subsystem:: | ||
176 | * PEERINFO Subsystem:: | ||
177 | * PEERSTORE Subsystem:: | ||
178 | * SET Subsystem:: | ||
179 | * STATISTICS Subsystem:: | ||
180 | * Distributed Hash Table (DHT):: | ||
181 | * GNU Name System (GNS):: | ||
182 | * GNS Namecache:: | ||
183 | * REVOCATION Subsystem:: | ||
184 | * File-sharing (FS) Subsystem:: | ||
185 | * REGEX Subsystem:: | ||
186 | |||
187 | @end detailmenu | ||
188 | @end menu | ||
189 | |||
190 | @c ********************************************************************* | ||
191 | @include chapters/philosophy.texi | ||
192 | @c ********************************************************************* | ||
193 | |||
194 | @include chapters/vocabulary.texi | ||
195 | |||
196 | @c ********************************************************************* | ||
197 | @include chapters/installation.texi | ||
198 | @c ********************************************************************* | ||
199 | |||
200 | @c ********************************************************************* | ||
201 | @include chapters/user.texi | ||
202 | @c ********************************************************************* | ||
203 | |||
204 | @include chapters/configuration.texi | ||
205 | |||
206 | @include chapters/contributing.texi | ||
207 | |||
208 | @c ********************************************************************* | ||
209 | @include chapters/developer.texi | ||
210 | @c @include gnunet-c-tutorial.texi | ||
211 | @c ********************************************************************* | ||
212 | |||
213 | @c ********************************************************************* | ||
214 | @node GNU Free Documentation License | ||
215 | @appendix GNU Free Documentation License | ||
216 | @cindex license, GNU Free Documentation License | ||
217 | @include fdl-1.3.texi | ||
218 | |||
219 | @c ********************************************************************* | ||
220 | @node GNU General Public License | ||
221 | @appendix GNU General Public License | ||
222 | @cindex license, GNU General Public License | ||
223 | @include gpl-3.0.texi | ||
224 | |||
225 | @c ********************************************************************* | ||
226 | @node Concept Index | ||
227 | @unnumbered Concept Index | ||
228 | @printindex cp | ||
229 | |||
230 | @node Programming Index | ||
231 | @unnumbered Programming Index | ||
232 | @syncodeindex tp fn | ||
233 | @syncodeindex vr fn | ||
234 | @printindex fn | ||
235 | |||
236 | @bye | ||
diff --git a/doc/documentation/gpl-3.0.texi b/doc/documentation/gpl-3.0.texi new file mode 100644 index 000000000..0e2e212ac --- /dev/null +++ b/doc/documentation/gpl-3.0.texi | |||
@@ -0,0 +1,717 @@ | |||
1 | @c The GNU General Public License. | ||
2 | @center Version 3, 29 June 2007 | ||
3 | |||
4 | @c This file is intended to be included within another document, | ||
5 | @c hence no sectioning command or @node. | ||
6 | |||
7 | @display | ||
8 | Copyright @copyright{} 2007 Free Software Foundation, Inc. @url{http://fsf.org/} | ||
9 | |||
10 | Everyone is permitted to copy and distribute verbatim copies of this | ||
11 | license document, but changing it is not allowed. | ||
12 | @end display | ||
13 | |||
14 | @heading Preamble | ||
15 | |||
16 | The GNU General Public License is a free, copyleft license for | ||
17 | software and other kinds of works. | ||
18 | |||
19 | The licenses for most software and other practical works are designed | ||
20 | to take away your freedom to share and change the works. By contrast, | ||
21 | the GNU General Public License is intended to guarantee your freedom | ||
22 | to share and change all versions of a program---to make sure it remains | ||
23 | free software for all its users. We, the Free Software Foundation, | ||
24 | use the GNU General Public License for most of our software; it | ||
25 | applies also to any other work released this way by its authors. You | ||
26 | can apply it to your programs, too. | ||
27 | |||
28 | When we speak of free software, we are referring to freedom, not | ||
29 | price. Our General Public Licenses are designed to make sure that you | ||
30 | have the freedom to distribute copies of free software (and charge for | ||
31 | them if you wish), that you receive source code or can get it if you | ||
32 | want it, that you can change the software or use pieces of it in new | ||
33 | free programs, and that you know you can do these things. | ||
34 | |||
35 | To protect your rights, we need to prevent others from denying you | ||
36 | these rights or asking you to surrender the rights. Therefore, you | ||
37 | have certain responsibilities if you distribute copies of the | ||
38 | software, or if you modify it: responsibilities to respect the freedom | ||
39 | of others. | ||
40 | |||
41 | For example, if you distribute copies of such a program, whether | ||
42 | gratis or for a fee, you must pass on to the recipients the same | ||
43 | freedoms that you received. You must make sure that they, too, | ||
44 | receive or can get the source code. And you must show them these | ||
45 | terms so they know their rights. | ||
46 | |||
47 | Developers that use the GNU GPL protect your rights with two steps: | ||
48 | (1) assert copyright on the software, and (2) offer you this License | ||
49 | giving you legal permission to copy, distribute and/or modify it. | ||
50 | |||
51 | For the developers' and authors' protection, the GPL clearly explains | ||
52 | that there is no warranty for this free software. For both users' and | ||
53 | authors' sake, the GPL requires that modified versions be marked as | ||
54 | changed, so that their problems will not be attributed erroneously to | ||
55 | authors of previous versions. | ||
56 | |||
57 | Some devices are designed to deny users access to install or run | ||
58 | modified versions of the software inside them, although the | ||
59 | manufacturer can do so. This is fundamentally incompatible with the | ||
60 | aim of protecting users' freedom to change the software. The | ||
61 | systematic pattern of such abuse occurs in the area of products for | ||
62 | individuals to use, which is precisely where it is most unacceptable. | ||
63 | Therefore, we have designed this version of the GPL to prohibit the | ||
64 | practice for those products. If such problems arise substantially in | ||
65 | other domains, we stand ready to extend this provision to those | ||
66 | domains in future versions of the GPL, as needed to protect the | ||
67 | freedom of users. | ||
68 | |||
69 | Finally, every program is threatened constantly by software patents. | ||
70 | States should not allow patents to restrict development and use of | ||
71 | software on general-purpose computers, but in those that do, we wish | ||
72 | to avoid the special danger that patents applied to a free program | ||
73 | could make it effectively proprietary. To prevent this, the GPL | ||
74 | assures that patents cannot be used to render the program non-free. | ||
75 | |||
76 | The precise terms and conditions for copying, distribution and | ||
77 | modification follow. | ||
78 | |||
79 | @heading TERMS AND CONDITIONS | ||
80 | |||
81 | @enumerate 0 | ||
82 | @item Definitions. | ||
83 | |||
84 | ``This License'' refers to version 3 of the GNU General Public License. | ||
85 | |||
86 | ``Copyright'' also means copyright-like laws that apply to other kinds | ||
87 | of works, such as semiconductor masks. | ||
88 | |||
89 | ``The Program'' refers to any copyrightable work licensed under this | ||
90 | License. Each licensee is addressed as ``you''. ``Licensees'' and | ||
91 | ``recipients'' may be individuals or organizations. | ||
92 | |||
93 | To ``modify'' a work means to copy from or adapt all or part of the work | ||
94 | in a fashion requiring copyright permission, other than the making of | ||
95 | an exact copy. The resulting work is called a ``modified version'' of | ||
96 | the earlier work or a work ``based on'' the earlier work. | ||
97 | |||
98 | A ``covered work'' means either the unmodified Program or a work based | ||
99 | on the Program. | ||
100 | |||
101 | To ``propagate'' a work means to do anything with it that, without | ||
102 | permission, would make you directly or secondarily liable for | ||
103 | infringement under applicable copyright law, except executing it on a | ||
104 | computer or modifying a private copy. Propagation includes copying, | ||
105 | distribution (with or without modification), making available to the | ||
106 | public, and in some countries other activities as well. | ||
107 | |||
108 | To ``convey'' a work means any kind of propagation that enables other | ||
109 | parties to make or receive copies. Mere interaction with a user | ||
110 | through a computer network, with no transfer of a copy, is not | ||
111 | conveying. | ||
112 | |||
113 | An interactive user interface displays ``Appropriate Legal Notices'' to | ||
114 | the extent that it includes a convenient and prominently visible | ||
115 | feature that (1) displays an appropriate copyright notice, and (2) | ||
116 | tells the user that there is no warranty for the work (except to the | ||
117 | extent that warranties are provided), that licensees may convey the | ||
118 | work under this License, and how to view a copy of this License. If | ||
119 | the interface presents a list of user commands or options, such as a | ||
120 | menu, a prominent item in the list meets this criterion. | ||
121 | |||
122 | @item Source Code. | ||
123 | |||
124 | The ``source code'' for a work means the preferred form of the work for | ||
125 | making modifications to it. ``Object code'' means any non-source form | ||
126 | of a work. | ||
127 | |||
128 | A ``Standard Interface'' means an interface that either is an official | ||
129 | standard defined by a recognized standards body, or, in the case of | ||
130 | interfaces specified for a particular programming language, one that | ||
131 | is widely used among developers working in that language. | ||
132 | |||
133 | The ``System Libraries'' of an executable work include anything, other | ||
134 | than the work as a whole, that (a) is included in the normal form of | ||
135 | packaging a Major Component, but which is not part of that Major | ||
136 | Component, and (b) serves only to enable use of the work with that | ||
137 | Major Component, or to implement a Standard Interface for which an | ||
138 | implementation is available to the public in source code form. A | ||
139 | ``Major Component'', in this context, means a major essential component | ||
140 | (kernel, window system, and so on) of the specific operating system | ||
141 | (if any) on which the executable work runs, or a compiler used to | ||
142 | produce the work, or an object code interpreter used to run it. | ||
143 | |||
144 | The ``Corresponding Source'' for a work in object code form means all | ||
145 | the source code needed to generate, install, and (for an executable | ||
146 | work) run the object code and to modify the work, including scripts to | ||
147 | control those activities. However, it does not include the work's | ||
148 | System Libraries, or general-purpose tools or generally available free | ||
149 | programs which are used unmodified in performing those activities but | ||
150 | which are not part of the work. For example, Corresponding Source | ||
151 | includes interface definition files associated with source files for | ||
152 | the work, and the source code for shared libraries and dynamically | ||
153 | linked subprograms that the work is specifically designed to require, | ||
154 | such as by intimate data communication or control flow between those | ||
155 | subprograms and other parts of the work. | ||
156 | |||
157 | The Corresponding Source need not include anything that users can | ||
158 | regenerate automatically from other parts of the Corresponding Source. | ||
159 | |||
160 | The Corresponding Source for a work in source code form is that same | ||
161 | work. | ||
162 | |||
163 | @item Basic Permissions. | ||
164 | |||
165 | All rights granted under this License are granted for the term of | ||
166 | copyright on the Program, and are irrevocable provided the stated | ||
167 | conditions are met. This License explicitly affirms your unlimited | ||
168 | permission to run the unmodified Program. The output from running a | ||
169 | covered work is covered by this License only if the output, given its | ||
170 | content, constitutes a covered work. This License acknowledges your | ||
171 | rights of fair use or other equivalent, as provided by copyright law. | ||
172 | |||
173 | You may make, run and propagate covered works that you do not convey, | ||
174 | without conditions so long as your license otherwise remains in force. | ||
175 | You may convey covered works to others for the sole purpose of having | ||
176 | them make modifications exclusively for you, or provide you with | ||
177 | facilities for running those works, provided that you comply with the | ||
178 | terms of this License in conveying all material for which you do not | ||
179 | control copyright. Those thus making or running the covered works for | ||
180 | you must do so exclusively on your behalf, under your direction and | ||
181 | control, on terms that prohibit them from making any copies of your | ||
182 | copyrighted material outside their relationship with you. | ||
183 | |||
184 | Conveying under any other circumstances is permitted solely under the | ||
185 | conditions stated below. Sublicensing is not allowed; section 10 | ||
186 | makes it unnecessary. | ||
187 | |||
188 | @item Protecting Users' Legal Rights From Anti-Circumvention Law. | ||
189 | |||
190 | No covered work shall be deemed part of an effective technological | ||
191 | measure under any applicable law fulfilling obligations under article | ||
192 | 11 of the WIPO copyright treaty adopted on 20 December 1996, or | ||
193 | similar laws prohibiting or restricting circumvention of such | ||
194 | measures. | ||
195 | |||
196 | When you convey a covered work, you waive any legal power to forbid | ||
197 | circumvention of technological measures to the extent such | ||
198 | circumvention is effected by exercising rights under this License with | ||
199 | respect to the covered work, and you disclaim any intention to limit | ||
200 | operation or modification of the work as a means of enforcing, against | ||
201 | the work's users, your or third parties' legal rights to forbid | ||
202 | circumvention of technological measures. | ||
203 | |||
204 | @item Conveying Verbatim Copies. | ||
205 | |||
206 | You may convey verbatim copies of the Program's source code as you | ||
207 | receive it, in any medium, provided that you conspicuously and | ||
208 | appropriately publish on each copy an appropriate copyright notice; | ||
209 | keep intact all notices stating that this License and any | ||
210 | non-permissive terms added in accord with section 7 apply to the code; | ||
211 | keep intact all notices of the absence of any warranty; and give all | ||
212 | recipients a copy of this License along with the Program. | ||
213 | |||
214 | You may charge any price or no price for each copy that you convey, | ||
215 | and you may offer support or warranty protection for a fee. | ||
216 | |||
217 | @item Conveying Modified Source Versions. | ||
218 | |||
219 | You may convey a work based on the Program, or the modifications to | ||
220 | produce it from the Program, in the form of source code under the | ||
221 | terms of section 4, provided that you also meet all of these | ||
222 | conditions: | ||
223 | |||
224 | @enumerate a | ||
225 | @item | ||
226 | The work must carry prominent notices stating that you modified it, | ||
227 | and giving a relevant date. | ||
228 | |||
229 | @item | ||
230 | The work must carry prominent notices stating that it is released | ||
231 | under this License and any conditions added under section 7. This | ||
232 | requirement modifies the requirement in section 4 to ``keep intact all | ||
233 | notices''. | ||
234 | |||
235 | @item | ||
236 | You must license the entire work, as a whole, under this License to | ||
237 | anyone who comes into possession of a copy. This License will | ||
238 | therefore apply, along with any applicable section 7 additional terms, | ||
239 | to the whole of the work, and all its parts, regardless of how they | ||
240 | are packaged. This License gives no permission to license the work in | ||
241 | any other way, but it does not invalidate such permission if you have | ||
242 | separately received it. | ||
243 | |||
244 | @item | ||
245 | If the work has interactive user interfaces, each must display | ||
246 | Appropriate Legal Notices; however, if the Program has interactive | ||
247 | interfaces that do not display Appropriate Legal Notices, your work | ||
248 | need not make them do so. | ||
249 | @end enumerate | ||
250 | |||
251 | A compilation of a covered work with other separate and independent | ||
252 | works, which are not by their nature extensions of the covered work, | ||
253 | and which are not combined with it such as to form a larger program, | ||
254 | in or on a volume of a storage or distribution medium, is called an | ||
255 | ``aggregate'' if the compilation and its resulting copyright are not | ||
256 | used to limit the access or legal rights of the compilation's users | ||
257 | beyond what the individual works permit. Inclusion of a covered work | ||
258 | in an aggregate does not cause this License to apply to the other | ||
259 | parts of the aggregate. | ||
260 | |||
261 | @item Conveying Non-Source Forms. | ||
262 | |||
263 | You may convey a covered work in object code form under the terms of | ||
264 | sections 4 and 5, provided that you also convey the machine-readable | ||
265 | Corresponding Source under the terms of this License, in one of these | ||
266 | ways: | ||
267 | |||
268 | @enumerate a | ||
269 | @item | ||
270 | Convey the object code in, or embodied in, a physical product | ||
271 | (including a physical distribution medium), accompanied by the | ||
272 | Corresponding Source fixed on a durable physical medium customarily | ||
273 | used for software interchange. | ||
274 | |||
275 | @item | ||
276 | Convey the object code in, or embodied in, a physical product | ||
277 | (including a physical distribution medium), accompanied by a written | ||
278 | offer, valid for at least three years and valid for as long as you | ||
279 | offer spare parts or customer support for that product model, to give | ||
280 | anyone who possesses the object code either (1) a copy of the | ||
281 | Corresponding Source for all the software in the product that is | ||
282 | covered by this License, on a durable physical medium customarily used | ||
283 | for software interchange, for a price no more than your reasonable | ||
284 | cost of physically performing this conveying of source, or (2) access | ||
285 | to copy the Corresponding Source from a network server at no charge. | ||
286 | |||
287 | @item | ||
288 | Convey individual copies of the object code with a copy of the written | ||
289 | offer to provide the Corresponding Source. This alternative is | ||
290 | allowed only occasionally and noncommercially, and only if you | ||
291 | received the object code with such an offer, in accord with subsection | ||
292 | 6b. | ||
293 | |||
294 | @item | ||
295 | Convey the object code by offering access from a designated place | ||
296 | (gratis or for a charge), and offer equivalent access to the | ||
297 | Corresponding Source in the same way through the same place at no | ||
298 | further charge. You need not require recipients to copy the | ||
299 | Corresponding Source along with the object code. If the place to copy | ||
300 | the object code is a network server, the Corresponding Source may be | ||
301 | on a different server (operated by you or a third party) that supports | ||
302 | equivalent copying facilities, provided you maintain clear directions | ||
303 | next to the object code saying where to find the Corresponding Source. | ||
304 | Regardless of what server hosts the Corresponding Source, you remain | ||
305 | obligated to ensure that it is available for as long as needed to | ||
306 | satisfy these requirements. | ||
307 | |||
308 | @item | ||
309 | Convey the object code using peer-to-peer transmission, provided you | ||
310 | inform other peers where the object code and Corresponding Source of | ||
311 | the work are being offered to the general public at no charge under | ||
312 | subsection 6d. | ||
313 | |||
314 | @end enumerate | ||
315 | |||
316 | A separable portion of the object code, whose source code is excluded | ||
317 | from the Corresponding Source as a System Library, need not be | ||
318 | included in conveying the object code work. | ||
319 | |||
320 | A ``User Product'' is either (1) a ``consumer product'', which means any | ||
321 | tangible personal property which is normally used for personal, | ||
322 | family, or household purposes, or (2) anything designed or sold for | ||
323 | incorporation into a dwelling. In determining whether a product is a | ||
324 | consumer product, doubtful cases shall be resolved in favor of | ||
325 | coverage. For a particular product received by a particular user, | ||
326 | ``normally used'' refers to a typical or common use of that class of | ||
327 | product, regardless of the status of the particular user or of the way | ||
328 | in which the particular user actually uses, or expects or is expected | ||
329 | to use, the product. A product is a consumer product regardless of | ||
330 | whether the product has substantial commercial, industrial or | ||
331 | non-consumer uses, unless such uses represent the only significant | ||
332 | mode of use of the product. | ||
333 | |||
334 | ``Installation Information'' for a User Product means any methods, | ||
335 | procedures, authorization keys, or other information required to | ||
336 | install and execute modified versions of a covered work in that User | ||
337 | Product from a modified version of its Corresponding Source. The | ||
338 | information must suffice to ensure that the continued functioning of | ||
339 | the modified object code is in no case prevented or interfered with | ||
340 | solely because modification has been made. | ||
341 | |||
342 | If you convey an object code work under this section in, or with, or | ||
343 | specifically for use in, a User Product, and the conveying occurs as | ||
344 | part of a transaction in which the right of possession and use of the | ||
345 | User Product is transferred to the recipient in perpetuity or for a | ||
346 | fixed term (regardless of how the transaction is characterized), the | ||
347 | Corresponding Source conveyed under this section must be accompanied | ||
348 | by the Installation Information. But this requirement does not apply | ||
349 | if neither you nor any third party retains the ability to install | ||
350 | modified object code on the User Product (for example, the work has | ||
351 | been installed in ROM). | ||
352 | |||
353 | The requirement to provide Installation Information does not include a | ||
354 | requirement to continue to provide support service, warranty, or | ||
355 | updates for a work that has been modified or installed by the | ||
356 | recipient, or for the User Product in which it has been modified or | ||
357 | installed. Access to a network may be denied when the modification | ||
358 | itself materially and adversely affects the operation of the network | ||
359 | or violates the rules and protocols for communication across the | ||
360 | network. | ||
361 | |||
362 | Corresponding Source conveyed, and Installation Information provided, | ||
363 | in accord with this section must be in a format that is publicly | ||
364 | documented (and with an implementation available to the public in | ||
365 | source code form), and must require no special password or key for | ||
366 | unpacking, reading or copying. | ||
367 | |||
368 | @item Additional Terms. | ||
369 | |||
370 | ``Additional permissions'' are terms that supplement the terms of this | ||
371 | License by making exceptions from one or more of its conditions. | ||
372 | Additional permissions that are applicable to the entire Program shall | ||
373 | be treated as though they were included in this License, to the extent | ||
374 | that they are valid under applicable law. If additional permissions | ||
375 | apply only to part of the Program, that part may be used separately | ||
376 | under those permissions, but the entire Program remains governed by | ||
377 | this License without regard to the additional permissions. | ||
378 | |||
379 | When you convey a copy of a covered work, you may at your option | ||
380 | remove any additional permissions from that copy, or from any part of | ||
381 | it. (Additional permissions may be written to require their own | ||
382 | removal in certain cases when you modify the work.) You may place | ||
383 | additional permissions on material, added by you to a covered work, | ||
384 | for which you have or can give appropriate copyright permission. | ||
385 | |||
386 | Notwithstanding any other provision of this License, for material you | ||
387 | add to a covered work, you may (if authorized by the copyright holders | ||
388 | of that material) supplement the terms of this License with terms: | ||
389 | |||
390 | @enumerate a | ||
391 | @item | ||
392 | Disclaiming warranty or limiting liability differently from the terms | ||
393 | of sections 15 and 16 of this License; or | ||
394 | |||
395 | @item | ||
396 | Requiring preservation of specified reasonable legal notices or author | ||
397 | attributions in that material or in the Appropriate Legal Notices | ||
398 | displayed by works containing it; or | ||
399 | |||
400 | @item | ||
401 | Prohibiting misrepresentation of the origin of that material, or | ||
402 | requiring that modified versions of such material be marked in | ||
403 | reasonable ways as different from the original version; or | ||
404 | |||
405 | @item | ||
406 | Limiting the use for publicity purposes of names of licensors or | ||
407 | authors of the material; or | ||
408 | |||
409 | @item | ||
410 | Declining to grant rights under trademark law for use of some trade | ||
411 | names, trademarks, or service marks; or | ||
412 | |||
413 | @item | ||
414 | Requiring indemnification of licensors and authors of that material by | ||
415 | anyone who conveys the material (or modified versions of it) with | ||
416 | contractual assumptions of liability to the recipient, for any | ||
417 | liability that these contractual assumptions directly impose on those | ||
418 | licensors and authors. | ||
419 | @end enumerate | ||
420 | |||
421 | All other non-permissive additional terms are considered ``further | ||
422 | restrictions'' within the meaning of section 10. If the Program as you | ||
423 | received it, or any part of it, contains a notice stating that it is | ||
424 | governed by this License along with a term that is a further | ||
425 | restriction, you may remove that term. If a license document contains | ||
426 | a further restriction but permits relicensing or conveying under this | ||
427 | License, you may add to a covered work material governed by the terms | ||
428 | of that license document, provided that the further restriction does | ||
429 | not survive such relicensing or conveying. | ||
430 | |||
431 | If you add terms to a covered work in accord with this section, you | ||
432 | must place, in the relevant source files, a statement of the | ||
433 | additional terms that apply to those files, or a notice indicating | ||
434 | where to find the applicable terms. | ||
435 | |||
436 | Additional terms, permissive or non-permissive, may be stated in the | ||
437 | form of a separately written license, or stated as exceptions; the | ||
438 | above requirements apply either way. | ||
439 | |||
440 | @item Termination. | ||
441 | |||
442 | You may not propagate or modify a covered work except as expressly | ||
443 | provided under this License. Any attempt otherwise to propagate or | ||
444 | modify it is void, and will automatically terminate your rights under | ||
445 | this License (including any patent licenses granted under the third | ||
446 | paragraph of section 11). | ||
447 | |||
448 | However, if you cease all violation of this License, then your license | ||
449 | from a particular copyright holder is reinstated (a) provisionally, | ||
450 | unless and until the copyright holder explicitly and finally | ||
451 | terminates your license, and (b) permanently, if the copyright holder | ||
452 | fails to notify you of the violation by some reasonable means prior to | ||
453 | 60 days after the cessation. | ||
454 | |||
455 | Moreover, your license from a particular copyright holder is | ||
456 | reinstated permanently if the copyright holder notifies you of the | ||
457 | violation by some reasonable means, this is the first time you have | ||
458 | received notice of violation of this License (for any work) from that | ||
459 | copyright holder, and you cure the violation prior to 30 days after | ||
460 | your receipt of the notice. | ||
461 | |||
462 | Termination of your rights under this section does not terminate the | ||
463 | licenses of parties who have received copies or rights from you under | ||
464 | this License. If your rights have been terminated and not permanently | ||
465 | reinstated, you do not qualify to receive new licenses for the same | ||
466 | material under section 10. | ||
467 | |||
468 | @item Acceptance Not Required for Having Copies. | ||
469 | |||
470 | You are not required to accept this License in order to receive or run | ||
471 | a copy of the Program. Ancillary propagation of a covered work | ||
472 | occurring solely as a consequence of using peer-to-peer transmission | ||
473 | to receive a copy likewise does not require acceptance. However, | ||
474 | nothing other than this License grants you permission to propagate or | ||
475 | modify any covered work. These actions infringe copyright if you do | ||
476 | not accept this License. Therefore, by modifying or propagating a | ||
477 | covered work, you indicate your acceptance of this License to do so. | ||
478 | |||
479 | @item Automatic Licensing of Downstream Recipients. | ||
480 | |||
481 | Each time you convey a covered work, the recipient automatically | ||
482 | receives a license from the original licensors, to run, modify and | ||
483 | propagate that work, subject to this License. You are not responsible | ||
484 | for enforcing compliance by third parties with this License. | ||
485 | |||
486 | An ``entity transaction'' is a transaction transferring control of an | ||
487 | organization, or substantially all assets of one, or subdividing an | ||
488 | organization, or merging organizations. If propagation of a covered | ||
489 | work results from an entity transaction, each party to that | ||
490 | transaction who receives a copy of the work also receives whatever | ||
491 | licenses to the work the party's predecessor in interest had or could | ||
492 | give under the previous paragraph, plus a right to possession of the | ||
493 | Corresponding Source of the work from the predecessor in interest, if | ||
494 | the predecessor has it or can get it with reasonable efforts. | ||
495 | |||
496 | You may not impose any further restrictions on the exercise of the | ||
497 | rights granted or affirmed under this License. For example, you may | ||
498 | not impose a license fee, royalty, or other charge for exercise of | ||
499 | rights granted under this License, and you may not initiate litigation | ||
500 | (including a cross-claim or counterclaim in a lawsuit) alleging that | ||
501 | any patent claim is infringed by making, using, selling, offering for | ||
502 | sale, or importing the Program or any portion of it. | ||
503 | |||
504 | @item Patents. | ||
505 | |||
506 | A ``contributor'' is a copyright holder who authorizes use under this | ||
507 | License of the Program or a work on which the Program is based. The | ||
508 | work thus licensed is called the contributor's ``contributor version''. | ||
509 | |||
510 | A contributor's ``essential patent claims'' are all patent claims owned | ||
511 | or controlled by the contributor, whether already acquired or | ||
512 | hereafter acquired, that would be infringed by some manner, permitted | ||
513 | by this License, of making, using, or selling its contributor version, | ||
514 | but do not include claims that would be infringed only as a | ||
515 | consequence of further modification of the contributor version. For | ||
516 | purposes of this definition, ``control'' includes the right to grant | ||
517 | patent sublicenses in a manner consistent with the requirements of | ||
518 | this License. | ||
519 | |||
520 | Each contributor grants you a non-exclusive, worldwide, royalty-free | ||
521 | patent license under the contributor's essential patent claims, to | ||
522 | make, use, sell, offer for sale, import and otherwise run, modify and | ||
523 | propagate the contents of its contributor version. | ||
524 | |||
525 | In the following three paragraphs, a ``patent license'' is any express | ||
526 | agreement or commitment, however denominated, not to enforce a patent | ||
527 | (such as an express permission to practice a patent or covenant not to | ||
528 | sue for patent infringement). To ``grant'' such a patent license to a | ||
529 | party means to make such an agreement or commitment not to enforce a | ||
530 | patent against the party. | ||
531 | |||
532 | If you convey a covered work, knowingly relying on a patent license, | ||
533 | and the Corresponding Source of the work is not available for anyone | ||
534 | to copy, free of charge and under the terms of this License, through a | ||
535 | publicly available network server or other readily accessible means, | ||
536 | then you must either (1) cause the Corresponding Source to be so | ||
537 | available, or (2) arrange to deprive yourself of the benefit of the | ||
538 | patent license for this particular work, or (3) arrange, in a manner | ||
539 | consistent with the requirements of this License, to extend the patent | ||
540 | license to downstream recipients. ``Knowingly relying'' means you have | ||
541 | actual knowledge that, but for the patent license, your conveying the | ||
542 | covered work in a country, or your recipient's use of the covered work | ||
543 | in a country, would infringe one or more identifiable patents in that | ||
544 | country that you have reason to believe are valid. | ||
545 | |||
546 | If, pursuant to or in connection with a single transaction or | ||
547 | arrangement, you convey, or propagate by procuring conveyance of, a | ||
548 | covered work, and grant a patent license to some of the parties | ||
549 | receiving the covered work authorizing them to use, propagate, modify | ||
550 | or convey a specific copy of the covered work, then the patent license | ||
551 | you grant is automatically extended to all recipients of the covered | ||
552 | work and works based on it. | ||
553 | |||
554 | A patent license is ``discriminatory'' if it does not include within the | ||
555 | scope of its coverage, prohibits the exercise of, or is conditioned on | ||
556 | the non-exercise of one or more of the rights that are specifically | ||
557 | granted under this License. You may not convey a covered work if you | ||
558 | are a party to an arrangement with a third party that is in the | ||
559 | business of distributing software, under which you make payment to the | ||
560 | third party based on the extent of your activity of conveying the | ||
561 | work, and under which the third party grants, to any of the parties | ||
562 | who would receive the covered work from you, a discriminatory patent | ||
563 | license (a) in connection with copies of the covered work conveyed by | ||
564 | you (or copies made from those copies), or (b) primarily for and in | ||
565 | connection with specific products or compilations that contain the | ||
566 | covered work, unless you entered into that arrangement, or that patent | ||
567 | license was granted, prior to 28 March 2007. | ||
568 | |||
569 | Nothing in this License shall be construed as excluding or limiting | ||
570 | any implied license or other defenses to infringement that may | ||
571 | otherwise be available to you under applicable patent law. | ||
572 | |||
573 | @item No Surrender of Others' Freedom. | ||
574 | |||
575 | If conditions are imposed on you (whether by court order, agreement or | ||
576 | otherwise) that contradict the conditions of this License, they do not | ||
577 | excuse you from the conditions of this License. If you cannot convey | ||
578 | a covered work so as to satisfy simultaneously your obligations under | ||
579 | this License and any other pertinent obligations, then as a | ||
580 | consequence you may not convey it at all. For example, if you agree | ||
581 | to terms that obligate you to collect a royalty for further conveying | ||
582 | from those to whom you convey the Program, the only way you could | ||
583 | satisfy both those terms and this License would be to refrain entirely | ||
584 | from conveying the Program. | ||
585 | |||
586 | @item Use with the GNU Affero General Public License. | ||
587 | |||
588 | Notwithstanding any other provision of this License, you have | ||
589 | permission to link or combine any covered work with a work licensed | ||
590 | under version 3 of the GNU Affero General Public License into a single | ||
591 | combined work, and to convey the resulting work. The terms of this | ||
592 | License will continue to apply to the part which is the covered work, | ||
593 | but the special requirements of the GNU Affero General Public License, | ||
594 | section 13, concerning interaction through a network will apply to the | ||
595 | combination as such. | ||
596 | |||
597 | @item Revised Versions of this License. | ||
598 | |||
599 | The Free Software Foundation may publish revised and/or new versions | ||
600 | of the GNU General Public License from time to time. Such new | ||
601 | versions will be similar in spirit to the present version, but may | ||
602 | differ in detail to address new problems or concerns. | ||
603 | |||
604 | Each version is given a distinguishing version number. If the Program | ||
605 | specifies that a certain numbered version of the GNU General Public | ||
606 | License ``or any later version'' applies to it, you have the option of | ||
607 | following the terms and conditions either of that numbered version or | ||
608 | of any later version published by the Free Software Foundation. If | ||
609 | the Program does not specify a version number of the GNU General | ||
610 | Public License, you may choose any version ever published by the Free | ||
611 | Software Foundation. | ||
612 | |||
613 | If the Program specifies that a proxy can decide which future versions | ||
614 | of the GNU General Public License can be used, that proxy's public | ||
615 | statement of acceptance of a version permanently authorizes you to | ||
616 | choose that version for the Program. | ||
617 | |||
618 | Later license versions may give you additional or different | ||
619 | permissions. However, no additional obligations are imposed on any | ||
620 | author or copyright holder as a result of your choosing to follow a | ||
621 | later version. | ||
622 | |||
623 | @item Disclaimer of Warranty. | ||
624 | |||
625 | THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY | ||
626 | APPLICABLE LAW@. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT | ||
627 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM ``AS IS'' WITHOUT | ||
628 | WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT | ||
629 | LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | ||
630 | A PARTICULAR PURPOSE@. THE ENTIRE RISK AS TO THE QUALITY AND | ||
631 | PERFORMANCE OF THE PROGRAM IS WITH YOU@. SHOULD THE PROGRAM PROVE | ||
632 | DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR | ||
633 | CORRECTION. | ||
634 | |||
635 | @item Limitation of Liability. | ||
636 | |||
637 | IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING | ||
638 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR | ||
639 | CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, | ||
640 | INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES | ||
641 | ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT | ||
642 | NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR | ||
643 | LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM | ||
644 | TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER | ||
645 | PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. | ||
646 | |||
647 | @item Interpretation of Sections 15 and 16. | ||
648 | |||
649 | If the disclaimer of warranty and limitation of liability provided | ||
650 | above cannot be given local legal effect according to their terms, | ||
651 | reviewing courts shall apply local law that most closely approximates | ||
652 | an absolute waiver of all civil liability in connection with the | ||
653 | Program, unless a warranty or assumption of liability accompanies a | ||
654 | copy of the Program in return for a fee. | ||
655 | |||
656 | @end enumerate | ||
657 | |||
658 | @heading END OF TERMS AND CONDITIONS | ||
659 | |||
660 | @heading How to Apply These Terms to Your New Programs | ||
661 | |||
662 | If you develop a new program, and you want it to be of the greatest | ||
663 | possible use to the public, the best way to achieve this is to make it | ||
664 | free software which everyone can redistribute and change under these | ||
665 | terms. | ||
666 | |||
667 | To do so, attach the following notices to the program. It is safest | ||
668 | to attach them to the start of each source file to most effectively | ||
669 | state the exclusion of warranty; and each file should have at least | ||
670 | the ``copyright'' line and a pointer to where the full notice is found. | ||
671 | |||
672 | @smallexample | ||
673 | @var{one line to give the program's name and a brief idea of what it does.} | ||
674 | Copyright (C) @var{year} @var{name of author} | ||
675 | |||
676 | This program is free software: you can redistribute it and/or modify | ||
677 | it under the terms of the GNU General Public License as published by | ||
678 | the Free Software Foundation, either version 3 of the License, or (at | ||
679 | your option) any later version. | ||
680 | |||
681 | This program is distributed in the hope that it will be useful, but | ||
682 | WITHOUT ANY WARRANTY; without even the implied warranty of | ||
683 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE@. See the GNU | ||
684 | General Public License for more details. | ||
685 | |||
686 | You should have received a copy of the GNU General Public License | ||
687 | along with this program. If not, see @url{http://www.gnu.org/licenses/}. | ||
688 | @end smallexample | ||
689 | |||
690 | Also add information on how to contact you by electronic and paper mail. | ||
691 | |||
692 | If the program does terminal interaction, make it output a short | ||
693 | notice like this when it starts in an interactive mode: | ||
694 | |||
695 | @smallexample | ||
696 | @var{program} Copyright (C) @var{year} @var{name of author} | ||
697 | This program comes with ABSOLUTELY NO WARRANTY; for details type @samp{show w}. | ||
698 | This is free software, and you are welcome to redistribute it | ||
699 | under certain conditions; type @samp{show c} for details. | ||
700 | @end smallexample | ||
701 | |||
702 | The hypothetical commands @samp{show w} and @samp{show c} should show | ||
703 | the appropriate parts of the General Public License. Of course, your | ||
704 | program's commands might be different; for a GUI interface, you would | ||
705 | use an ``about box''. | ||
706 | |||
707 | You should also get your employer (if you work as a programmer) or school, | ||
708 | if any, to sign a ``copyright disclaimer'' for the program, if necessary. | ||
709 | For more information on this, and how to apply and follow the GNU GPL, see | ||
710 | @url{http://www.gnu.org/licenses/}. | ||
711 | |||
712 | The GNU General Public License does not permit incorporating your | ||
713 | program into proprietary programs. If your program is a subroutine | ||
714 | library, you may consider it more useful to permit linking proprietary | ||
715 | applications with the library. If this is what you want to do, use | ||
716 | the GNU Lesser General Public License instead of this License. But | ||
717 | first, please read @url{http://www.gnu.org/philosophy/why-not-lgpl.html}. | ||
diff --git a/doc/documentation/htmlxref.cnf b/doc/documentation/htmlxref.cnf new file mode 100644 index 000000000..a4928f6fe --- /dev/null +++ b/doc/documentation/htmlxref.cnf | |||
@@ -0,0 +1,668 @@ | |||
1 | # htmlxref.cnf - reference file for free Texinfo manuals on the web. | ||
2 | # Modified by Ludovic Courtès <ludo@gnu.org> for the GNU Guix manual. | ||
3 | # Modified by ng0 <ng0@gnunet.org> for the GNUnet manual. | ||
4 | |||
5 | htmlxrefversion=2017-10-26.06; # UTC | ||
6 | |||
7 | # Copyright 2010, 2011, 2012, 2013, 2014, 2015 Free Software Foundation, Inc. | ||
8 | # | ||
9 | # Copying and distribution of this file, with or without modification, | ||
10 | # are permitted in any medium without royalty provided the copyright | ||
11 | # notice and this notice are preserved. | ||
12 | # | ||
13 | # The latest version of this file is available at | ||
14 | # http://ftpmirror.gnu.org/texinfo/htmlxref.cnf. | ||
15 | # Email corrections or additions to bug-texinfo@gnu.org. | ||
16 | # The primary goal is to list all relevant GNU manuals; | ||
17 | # other free manuals are also welcome. | ||
18 | # | ||
19 | # To be included in this list, a manual must: | ||
20 | # | ||
21 | # - have a generic url, e.g., no version numbers; | ||
22 | # - have a unique file name (e.g., manual identifier), i.e., be related to the | ||
23 | # package name. Things like "refman" or "tutorial" don't work. | ||
24 | # - follow the naming convention for nodes described at | ||
25 | # http://www.gnu.org/software/texinfo/manual/texinfo/html_node/HTML-Xref.html | ||
26 | # This is what makeinfo and texi2html implement. | ||
27 | # | ||
28 | # Unless the above criteria are met, it's not possible to generate | ||
29 | # reliable cross-manual references. | ||
30 | # | ||
31 | # For information on automatically generating all the useful formats for | ||
32 | # a manual to put on the web, see | ||
33 | # http://www.gnu.org/prep/maintain/html_node/Manuals-on-Web-Pages.html. | ||
34 | |||
35 | # For people editing this file: when a manual named foo is related to a | ||
36 | # package named bar, the url should contain a variable reference ${BAR}. | ||
37 | # Otherwise, the gnumaint scripts have no way of knowing they are | ||
38 | # associated, and thus gnu.org/manual can't include them. | ||
39 | |||
40 | # shorten references to manuals on www.gnu.org. | ||
41 | G = https://www.gnu.org | ||
42 | GS = ${G}/software | ||
43 | |||
44 | 3dldf mono ${GS}/3dldf/manual/user_ref/3DLDF.html | ||
45 | 3dldf node ${GS}/3dldf/manual/user_ref/ | ||
46 | |||
47 | alive mono ${GS}/alive/manual/alive.html | ||
48 | alive node ${GS}/alive/manual/html_node/ | ||
49 | |||
50 | anubis chapter ${GS}/anubis/manual/html_chapter/ | ||
51 | anubis section ${GS}/anubis/manual/html_section/ | ||
52 | anubis node ${GS}/anubis/manual/html_node/ | ||
53 | |||
54 | artanis mono ${GS}/artanis/manual/artanis.html | ||
55 | artanis node ${GS}/artanis/manual/html_node/ | ||
56 | |||
57 | aspell section http://aspell.net/man-html/index.html | ||
58 | |||
59 | auctex mono ${GS}/auctex/manual/auctex.html | ||
60 | auctex node ${GS}/auctex/manual/auctex/ | ||
61 | |||
62 | autoconf mono ${GS}/autoconf/manual/autoconf.html | ||
63 | autoconf node ${GS}/autoconf/manual/html_node/ | ||
64 | |||
65 | autogen mono ${GS}/autogen/manual/html_mono/autogen.html | ||
66 | autogen chapter ${GS}/autogen/manual/html_chapter/ | ||
67 | autogen node ${GS}/autoconf/manual/html_node/ | ||
68 | |||
69 | automake mono ${GS}/automake/manual/automake.html | ||
70 | automake node ${GS}/automake/manual/html_node/ | ||
71 | |||
72 | avl node http://www.stanford.edu/~blp/avl/libavl.html/ | ||
73 | |||
74 | bash mono ${GS}/bash/manual/bash.html | ||
75 | bash node ${GS}/bash/manual/html_node/ | ||
76 | |||
77 | BINUTILS = http://sourceware.org/binutils/docs | ||
78 | binutils node ${BINUTILS}/binutils/ | ||
79 | as node ${BINUTILS}/as/ | ||
80 | bfd node ${BINUTILS}/bfd/ | ||
81 | gprof node ${BINUTILS}/gprof/ | ||
82 | ld node ${BINUTILS}/ld/ | ||
83 | |||
84 | bison mono ${GS}/bison/manual/bison.html | ||
85 | bison node ${GS}/bison/manual/html_node/ | ||
86 | |||
87 | bpel2owfn mono ${GS}/bpel2owfn/manual/2.0.x/bpel2owfn.html | ||
88 | |||
89 | ccd2cue mono ${GS}/ccd2cue/manual/ccd2cue.html | ||
90 | ccd2cue node ${GS}/ccd2cue/manual/html_node/ | ||
91 | |||
92 | cflow mono ${GS}/cflow/manual/cflow.html | ||
93 | cflow node ${GS}/cflow/manual/html_node/ | ||
94 | |||
95 | chess mono ${GS}/chess/manual/gnuchess.html | ||
96 | chess node ${GS}/chess/manual/html_node/ | ||
97 | |||
98 | combine mono ${GS}/combine/manual/combine.html | ||
99 | combine chapter ${GS}/combine/manual/html_chapter/ | ||
100 | combine section ${GS}/combine/manual/html_section/ | ||
101 | combine node ${GS}/combine/manual/html_node/ | ||
102 | |||
103 | complexity mono ${GS}/complexity/manual/complexity.html | ||
104 | complexity node ${GS}/complexity/manual/html_node/ | ||
105 | |||
106 | coreutils mono ${GS}/coreutils/manual/coreutils | ||
107 | coreutils node ${GS}/coreutils/manual/html_node/ | ||
108 | |||
109 | cpio mono ${GS}/cpio/manual/cpio | ||
110 | cpio node ${GS}/cpio/manual/html_node/ | ||
111 | |||
112 | cssc node ${GS}/cssc/manual/ | ||
113 | |||
114 | #cvs cannot be handled here; see http://ximbiot.com/cvs/manual. | ||
115 | |||
116 | ddd mono ${GS}/ddd/manual/html_mono/ddd.html | ||
117 | |||
118 | ddrescue mono ${GS}/ddrescue/manual/ddrescue_manual.html | ||
119 | |||
120 | DICO = http://puszcza.gnu.org.ua/software/dico/manual | ||
121 | dico mono ${DICO}/dico.html | ||
122 | dico chapter ${DICO}/html_chapter/ | ||
123 | dico section ${DICO}/html_section/ | ||
124 | dico node ${DICO}/html_node/ | ||
125 | |||
126 | diffutils mono ${GS}/diffutils/manual/diffutils | ||
127 | diffutils node ${GS}/diffutils/manual/html_node/ | ||
128 | |||
129 | ed mono ${GS}/ed/manual/ed_manual.html | ||
130 | |||
131 | EMACS = ${GS}/emacs/manual | ||
132 | emacs mono ${EMACS}/html_mono/emacs.html | ||
133 | emacs node ${EMACS}/html_node/emacs/ | ||
134 | # | ||
135 | ada-mode mono ${EMACS}/html_mono/ada-mode.html | ||
136 | ada-mode node ${EMACS}/html_node/ada-mode/ | ||
137 | # | ||
138 | autotype mono ${EMACS}/html_mono/autotype.html | ||
139 | autotype node ${EMACS}/html_node/autotype/ | ||
140 | # | ||
141 | ccmode mono ${EMACS}/html_mono/ccmode.html | ||
142 | ccmode node ${EMACS}/html_node/ccmode/ | ||
143 | # | ||
144 | cl mono ${EMACS}/html_mono/cl.html | ||
145 | cl node ${EMACS}/html_node/cl/ | ||
146 | # | ||
147 | ebrowse mono ${EMACS}/html_mono/ebrowse.html | ||
148 | ebrowse node ${EMACS}/html_node/ebrowse/ | ||
149 | # | ||
150 | ediff mono ${EMACS}/html_mono/ediff.html | ||
151 | ediff node ${EMACS}/html_node/ediff/ | ||
152 | # | ||
153 | eieio mono ${EMACS}/html_mono/eieio.html | ||
154 | eieio node ${EMACS}/html_node/eieio/ | ||
155 | # | ||
156 | elisp mono ${EMACS}/html_mono/elisp.html | ||
157 | elisp node ${EMACS}/html_node/elisp/ | ||
158 | # | ||
159 | epa mono ${EMACS}/html_mono/epa.html | ||
160 | epa node ${EMACS}/html_node/epa/ | ||
161 | # | ||
162 | erc mono ${EMACS}/html_mono/erc.html | ||
163 | erc node ${EMACS}/html_node/erc/ | ||
164 | # | ||
165 | dired-x mono ${EMACS}/html_mono/dired-x.html | ||
166 | dired-x node ${EMACS}/html_node/dired-x/ | ||
167 | # | ||
168 | eshell mono ${EMACS}/html_mono/eshell.html | ||
169 | eshell node ${EMACS}/html_node/eshell/ | ||
170 | # | ||
171 | flymake mono ${EMACS}/html_mono/flymake.html | ||
172 | flymake node ${EMACS}/html_node/flymake/ | ||
173 | # | ||
174 | gnus mono ${EMACS}/html_mono/gnus.html | ||
175 | gnus node ${EMACS}/html_node/gnus/ | ||
176 | # | ||
177 | idlwave mono ${EMACS}/html_mono/idlwave.html | ||
178 | idlwave node ${EMACS}/html_node/idlwave/ | ||
179 | # | ||
180 | message mono ${EMACS}/html_mono/message.html | ||
181 | message node ${EMACS}/html_node/message/ | ||
182 | # | ||
183 | mh-e mono ${EMACS}/html_mono/mh-e.html | ||
184 | mh-e node ${EMACS}/html_node/mh-e/ | ||
185 | # | ||
186 | nxml-mode mono ${EMACS}/html_mono/nxml-mode.html | ||
187 | nxml-mode node ${EMACS}/html_node/nxml-mode/ | ||
188 | # | ||
189 | org mono ${EMACS}/html_mono/org.html | ||
190 | org node ${EMACS}/html_node/org/ | ||
191 | # | ||
192 | pcl-cvs mono ${EMACS}/html_mono/pcl-cvs.html | ||
193 | pcl-cvs node ${EMACS}/html_node/pcl-cvs/ | ||
194 | # | ||
195 | rcirc mono ${EMACS}/html_mono/rcirc.html | ||
196 | rcirc node ${EMACS}/html_node/rcirc/ | ||
197 | # | ||
198 | semantic mono ${EMACS}/html_mono/semantic.html | ||
199 | semantic node ${EMACS}/html_node/semantic/ | ||
200 | # | ||
201 | smtp mono ${EMACS}/html_mono/smtpmail.html | ||
202 | smtp node ${EMACS}/html_node/smtpmail/ | ||
203 | # | ||
204 | speedbar mono ${EMACS}/html_mono/speedbar.html | ||
205 | speedbar node ${EMACS}/html_node/speedbar/ | ||
206 | # | ||
207 | tramp mono ${EMACS}/html_mono/tramp.html | ||
208 | tramp node ${EMACS}/html_node/tramp/ | ||
209 | # | ||
210 | vip mono ${EMACS}/html_mono/vip.html | ||
211 | vip node ${EMACS}/html_node/vip/ | ||
212 | # | ||
213 | viper mono ${EMACS}/html_mono/viper.html | ||
214 | viper node ${EMACS}/html_node/viper/ | ||
215 | # | ||
216 | woman mono ${EMACS}/html_mono/woman.html | ||
217 | woman node ${EMACS}/html_node/woman/ | ||
218 | # (end emacs manuals) | ||
219 | |||
220 | easejs mono ${GS}/easejs/manual/easejs.html | ||
221 | easejs node ${GS}/easejs/manual/ | ||
222 | |||
223 | EMACS_GUIX = https://alezost.github.io/guix.el/manual/latest | ||
224 | emacs-guix mono ${EMACS_GUIX}/emacs-guix.html | ||
225 | emacs-guix node ${EMACS_GUIX}/html_node/ | ||
226 | |||
227 | emacs-muse node ${GS}/emacs-muse/manual/muse.html | ||
228 | emacs-muse node ${GS}/emacs-muse/manual/html_node/ | ||
229 | |||
230 | emms node ${GS}/emms/manual/ | ||
231 | |||
232 | # The file is called 'find.info' but the package is 'findutils'. | ||
233 | find mono ${GS}/findutils/manual/html_mono/find.html | ||
234 | find node ${GS}/findutils/manual/html_node/find_html | ||
235 | findutils mono ${GS}/findutils/manual/html_mono/find.html | ||
236 | findutils node ${GS}/findutils/manual/html_node/find_html | ||
237 | |||
238 | FLEX = http://flex.sourceforge.net | ||
239 | flex node ${FLEX}/manual/ | ||
240 | |||
241 | gama mono ${GS}/gama/manual/gama.html | ||
242 | gama node ${GS}/gama/manual/html_node/ | ||
243 | |||
244 | GAWK = ${GS}/gawk/manual | ||
245 | gawk mono ${GAWK}/gawk.html | ||
246 | gawk node ${GAWK}/html_node/ | ||
247 | gawkinet mono ${GAWK}/gawkinet/gawkinet.html | ||
248 | gawkinet node ${GAWK}/gawkinet/html_node/ | ||
249 | |||
250 | gcal mono ${GS}/gcal/manual/gcal.html | ||
251 | gcal node ${GS}/gcal/manual/html_node/ | ||
252 | |||
253 | GCC = http://gcc.gnu.org/onlinedocs | ||
254 | gcc node ${GCC}/gcc/ | ||
255 | cpp node ${GCC}/cpp/ | ||
256 | gcj node ${GCC}/gcj/ | ||
257 | gfortran node ${GCC}/gfortran/ | ||
258 | gnat_rm node ${GCC}/gnat_rm/ | ||
259 | gnat_ugn_unw node ${GCC}/gnat_ugn_unw/ | ||
260 | libgomp node ${GCC}/libgomp/ | ||
261 | libstdc++ node ${GCC}/libstdc++/ | ||
262 | # | ||
263 | gccint node ${GCC}/gccint/ | ||
264 | cppinternals node ${GCC}/cppinternals/ | ||
265 | gfc-internals node ${GCC}/gfc-internals/ | ||
266 | gnat-style node ${GCC}/gnat-style/ | ||
267 | libiberty node ${GCC}/libiberty/ | ||
268 | |||
269 | GDB = http://sourceware.org/gdb/current/onlinedocs | ||
270 | gdb node ${GDB}/gdb/ | ||
271 | stabs node ${GDB}/stabs/ | ||
272 | |||
273 | GDBM = http://www.gnu.org.ua/software/gdbm/manual | ||
274 | gdbm mono ${GDBM}/gdbm.html | ||
275 | gdbm chapter ${GDBM}/html_chapter/ | ||
276 | gdbm section ${GDBM}/html_section/ | ||
277 | gdbm node ${GDBM}/html_node/ | ||
278 | |||
279 | gettext mono ${GS}/gettext/manual/gettext.html | ||
280 | gettext node ${GS}/gettext/manual/html_node/ | ||
281 | |||
282 | gforth node http://www.complang.tuwien.ac.at/forth/gforth/Docs-html/ | ||
283 | |||
284 | global mono ${GS}/global/manual/global.html | ||
285 | |||
286 | gmediaserver node ${GS}/gmediaserver/manual/ | ||
287 | |||
288 | gmp node http://www.gmplib.org/manual/ | ||
289 | |||
290 | gnu-arch node ${GS}/gnu-arch/tutorial/ | ||
291 | |||
292 | gnu-c-manual mono ${GS}/gnu-c-manual/gnu-c-manual.html | ||
293 | |||
294 | gnu-crypto node ${GS}/gnu-crypto/manual/ | ||
295 | |||
296 | gnubg mono ${GS}/gnubg/manual/gnubg.html | ||
297 | gnubg node ${GS}/gnubg/manual/html_node/ | ||
298 | |||
299 | gnubik mono ${GS}/gnubik/manual/gnubik.html | ||
300 | gnubik node ${GS}/gnubik/manual/html_node/ | ||
301 | |||
302 | gnulib mono ${GS}/gnulib/manual/gnulib.html | ||
303 | gnulib node ${GS}/gnulib/manual/html_node/ | ||
304 | |||
305 | GNUN = ${GS}/trans-coord/manual | ||
306 | gnun mono ${GNUN}/gnun/gnun.html | ||
307 | gnun node ${GNUN}/gnun/html_node/ | ||
308 | web-trans mono ${GNUN}/web-trans/web-trans.html | ||
309 | web-trans node ${GNUN}/web-trans/html_node/ | ||
310 | |||
311 | GNUNET = https://docs.gnunet.org/manuals | ||
312 | gnunet node ${GNUNET}/gnunet/ | ||
313 | gnunet-c-tutorial node ${GNUNET}/gnunet-c-tutorial/ | ||
314 | gnunet-java-tutorial node ${GNUNET}/gnunet-java-tutorial/ | ||
315 | |||
316 | GNUPG = http://www.gnupg.org/documentation/manuals | ||
317 | gnupg node ${GNUPG}/gnupg/ | ||
318 | dirmngr node ${GNUPG}/dirmngr/ | ||
319 | gcrypt node ${GNUPG}/gcrypt/ | ||
320 | libgcrypt node ${GNUPG}/gcrypt/ | ||
321 | ksba node ${GNUPG}/ksba/ | ||
322 | assuan node ${GNUPG}/assuan/ | ||
323 | gpgme node ${GNUPG}/gpgme/ | ||
324 | |||
325 | gnuprologjava node ${GS}/gnuprologjava/manual/ | ||
326 | |||
327 | gnuschool mono ${GS}/gnuschool/gnuschool.html | ||
328 | |||
329 | GNUSTANDARDS = ${G}/prep | ||
330 | maintain mono ${GNUSTANDARDS}/maintain/maintain.html | ||
331 | maintain node ${GNUSTANDARDS}/maintain/html_node/ | ||
332 | # | ||
333 | standards mono ${GNUSTANDARDS}/standards/standards.html | ||
334 | standards node ${GNUSTANDARDS}/standards/html_node/ | ||
335 | |||
336 | gnutls mono http://gnutls.org/manual/gnutls.html | ||
337 | gnutls node http://gnutls.org/manual/html_node/ | ||
338 | |||
339 | gnutls-guile mono http://gnutls.org/manual/gnutls-guile.html | ||
340 | gnutls-guile node http://gnutls.org/manual/gnutls-guile/ | ||
341 | |||
342 | gperf mono ${GS}/gperf/manual/gperf.html | ||
343 | gperf node ${GS}/gperf/manual/html_node/ | ||
344 | |||
345 | grep mono ${GS}/grep/manual/grep.html | ||
346 | grep node ${GS}/grep/manual/html_node/ | ||
347 | |||
348 | groff node ${GS}/groff/manual/html_node/ | ||
349 | |||
350 | GRUB = ${GS}/grub/manual | ||
351 | grub mono ${GRUB}/grub.html | ||
352 | grub node ${GRUB}/html_node/ | ||
353 | # | ||
354 | multiboot mono ${GRUB}/multiboot/multiboot.html | ||
355 | multiboot node ${GRUB}/multiboot/html_node/ | ||
356 | |||
357 | gsasl mono ${GS}/gsasl/manual/gsasl.html | ||
358 | gsasl node ${GS}/gsasl/manual/html_node/ | ||
359 | |||
360 | gsl node ${GS}/gsl/manual/html_node/ | ||
361 | |||
362 | gsrc mono ${GS}/gsrc/manual/gsrc.html | ||
363 | gsrc node ${GS}/gsrc/manual/html_node/ | ||
364 | |||
365 | gss mono ${GS}/gss/manual/gss.html | ||
366 | gss node ${GS}/gss/manual/html_node/ | ||
367 | |||
368 | gtypist mono ${GS}/gtypist/doc/ | ||
369 | |||
370 | guile mono ${GS}/guile/manual/guile.html | ||
371 | guile node ${GS}/guile/manual/html_node/ | ||
372 | |||
373 | guile-avahi mono http://nongnu.org/guile-avahi/doc/guile-avahi.html | ||
374 | |||
375 | GUILE_GNOME = ${GS}/guile-gnome/docs | ||
376 | gobject node ${GUILE_GNOME}/gobject/html/ | ||
377 | glib node ${GUILE_GNOME}/glib/html/ | ||
378 | atk node ${GUILE_GNOME}/atk/html/ | ||
379 | pango node ${GUILE_GNOME}/pango/html/ | ||
380 | pangocairo node ${GUILE_GNOME}/pangocairo/html/ | ||
381 | gdk node ${GUILE_GNOME}/gdk/html/ | ||
382 | gtk node ${GUILE_GNOME}/gtk/html/ | ||
383 | libglade node ${GUILE_GNOME}/libglade/html/ | ||
384 | gnome-vfs node ${GUILE_GNOME}/gnome-vfs/html/ | ||
385 | libgnomecanvas node ${GUILE_GNOME}/libgnomecanvas/html/ | ||
386 | gconf node ${GUILE_GNOME}/gconf/html/ | ||
387 | libgnome node ${GUILE_GNOME}/libgnome/html/ | ||
388 | libgnomeui node ${GUILE_GNOME}/libgnomeui/html/ | ||
389 | corba node ${GUILE_GNOME}/corba/html/ | ||
390 | clutter node ${GUILE_GNOME}/clutter/html/ | ||
391 | clutter-glx node ${GUILE_GNOME}/clutter-glx/html/ | ||
392 | |||
393 | guile-gtk node ${GS}/guile-gtk/docs/guile-gtk/ | ||
394 | |||
395 | guile-rpc mono ${GS}/guile-rpc/manual/guile-rpc.html | ||
396 | guile-rpc node ${GS}/guile-rpc/manual/html_node/ | ||
397 | |||
398 | guix mono ${GS}/guix/manual/guix.html | ||
399 | guix node ${GS}/guix/manual/html_node/ | ||
400 | |||
401 | gv mono ${GS}/gv/manual/gv.html | ||
402 | gv node ${GS}/gv/manual/html_node/ | ||
403 | |||
404 | gzip mono ${GS}/gzip/manual/gzip.html | ||
405 | gzip node ${GS}/gzip/manual/html_node/ | ||
406 | |||
407 | hello mono ${GS}/hello/manual/hello.html | ||
408 | hello node ${GS}/hello/manual/html_node/ | ||
409 | |||
410 | help2man mono ${GS}/help2man/help2man.html | ||
411 | |||
412 | idutils mono ${GS}/idutils/manual/idutils.html | ||
413 | idutils node ${GS}/idutils/manual/html_node/ | ||
414 | |||
415 | inetutils mono ${GS}/inetutils/manual/inetutils.html | ||
416 | inetutils node ${GS}/inetutils/manual/html_node/ | ||
417 | |||
418 | jwhois mono ${GS}/jwhois/manual/jwhois.html | ||
419 | jwhois node ${GS}/jwhois/manual/html_node/ | ||
420 | |||
421 | libc mono ${GS}/libc/manual/html_mono/libc.html | ||
422 | libc node ${GS}/libc/manual/html_node/ | ||
423 | |||
424 | LIBCDIO = ${GS}/libcdio | ||
425 | libcdio mono ${LIBCDIO}/libcdio.html | ||
426 | cd-text mono ${LIBCDIO}/cd-text-format.html | ||
427 | |||
428 | libextractor mono ${GS}/libextractor/manual/libextractor.html | ||
429 | libextractor node ${GS}/libextractor/manual/html_node/ | ||
430 | |||
431 | libidn mono ${GS}/libidn/manual/libidn.html | ||
432 | libidn node ${GS}/libidn/manual/html_node/ | ||
433 | |||
434 | librejs mono ${GS}/librejs/manual/librejs.html | ||
435 | librejs node ${GS}/librejs/manual/html_node/ | ||
436 | |||
437 | libmatheval mono ${GS}/libmatheval/manual/libmatheval.html | ||
438 | |||
439 | LIBMICROHTTPD = ${GS}/libmicrohttpd | ||
440 | libmicrohttpd mono ${LIBMICROHTTPD}/manual/libmicrohttpd.html | ||
441 | libmicrohttpd node ${LIBMICROHTTPD}/manual/html_node/ | ||
442 | microhttpd-tutorial mono ${LIBMICROHTTPD}/tutorial.html | ||
443 | |||
444 | libtasn1 mono ${GS}/libtasn1/manual/libtasn1.html | ||
445 | libtasn1 node ${GS}/libtasn1/manual/html_node/ | ||
446 | |||
447 | libtool mono ${GS}/libtool/manual/libtool.html | ||
448 | libtool node ${GS}/libtool/manual/html_node/ | ||
449 | |||
450 | lightning mono ${GS}/lightning/manual/lightning.html | ||
451 | lightning node ${GS}/lightning/manual/html_node/ | ||
452 | |||
453 | # The stable/ url redirects immediately, but that's ok. | ||
454 | # The .html extension is omitted on their web site, but it works if given. | ||
455 | LILYPOND = http://lilypond.org/doc/stable/Documentation | ||
456 | lilypond-internals node ${LILYPOND}/internals/ | ||
457 | lilypond-learning node ${LILYPOND}/learning/ | ||
458 | lilypond-notation node ${LILYPOND}/notation/ | ||
459 | lilypond-snippets node ${LILYPOND}/snippets/ | ||
460 | lilypond-usage node ${LILYPOND}/usage/ | ||
461 | lilypond-web node ${LILYPOND}/web/ | ||
462 | music-glossary node ${LILYPOND}/music-glossary/ | ||
463 | |||
464 | liquidwar6 mono ${GS}/liquidwar6/manual/liquidwar6.html | ||
465 | liquidwar6 node ${GS}/liquidwar6/manual/html_node/ | ||
466 | |||
467 | lispintro mono ${GS}/emacs/emacs-lisp-intro/html_mono/emacs-lisp-intro.html | ||
468 | lispintro node ${GS}/emacs/emacs-lisp-intro/html_node/index.html | ||
469 | |||
470 | LSH = http://www.lysator.liu.se/~nisse/lsh | ||
471 | lsh mono ${LSH}/lsh.html | ||
472 | |||
473 | m4 mono ${GS}/m4/manual/m4.html | ||
474 | m4 node ${GS}/m4/manual/html_node/ | ||
475 | |||
476 | mailutils mono ${GS}/mailutils/manual/mailutils.html | ||
477 | mailutils chapter ${GS}/mailutils/manual/html_chapter/ | ||
478 | mailutils section ${GS}/mailutils/manual/html_section/ | ||
479 | mailutils node ${GS}/mailutils/manual/html_node/ | ||
480 | |||
481 | make mono ${GS}/make/manual/make.html | ||
482 | make node ${GS}/make/manual/html_node/ | ||
483 | |||
484 | mcron mono ${GS}/mcron/manual/mcron.html | ||
485 | mcron node ${GS}/mcron/manual/html_node/ | ||
486 | |||
487 | mdk mono ${GS}/mdk/manual/mdk.html | ||
488 | mdk node ${GS}/mdk/manual/html_node/ | ||
489 | |||
490 | METAEXCHANGE = http://ftp.gwdg.de/pub/gnu2/iwfmdh/doc/texinfo | ||
491 | iwf_mh node ${METAEXCHANGE}/iwf_mh.html | ||
492 | scantest node ${METAEXCHANGE}/scantest.html | ||
493 | |||
494 | MIT_SCHEME = ${GS}/mit-scheme/documentation | ||
495 | mit-scheme-ref node ${MIT_SCHEME}/mit-scheme-ref/ | ||
496 | mit-scheme-user node ${MIT_SCHEME}/mit-scheme-user/ | ||
497 | sos node ${MIT_SCHEME}/mit-scheme-sos/ | ||
498 | mit-scheme-imail node ${MIT_SCHEME}/mit-scheme-imail/ | ||
499 | |||
500 | moe mono ${GS}/moe/manual/moe_manual.html | ||
501 | |||
502 | motti node ${GS}/motti/manual/ | ||
503 | |||
504 | mpc node http://www.multiprecision.org/index.php?prog=mpc&page=html | ||
505 | |||
506 | mpfr mono http://www.mpfr.org/mpfr-current/mpfr.html | ||
507 | |||
508 | mtools mono ${GS}/mtools/manual/mtools.html | ||
509 | |||
510 | myserver node http://www.myserverproject.net/documentation/ | ||
511 | |||
512 | nano mono http://www.nano-editor.org/dist/latest/nano.html | ||
513 | |||
514 | nettle chapter http://www.lysator.liu.se/~nisse/nettle/nettle.html | ||
515 | |||
516 | ocrad mono ${GS}/ocrad/manual/ocrad_manual.html | ||
517 | |||
518 | parted mono ${GS}/parted/manual/parted.html | ||
519 | parted node ${GS}/parted/manual/html_node/ | ||
520 | |||
521 | pascal mono http://www.gnu-pascal.de/gpc/ | ||
522 | |||
523 | # can't use pcb since url's contain dates --30nov10 | ||
524 | |||
525 | perl mono ${GS}/perl/manual/perldoc-all.html | ||
526 | |||
527 | PIES = http://www.gnu.org.ua/software/pies/manual | ||
528 | pies mono ${PIES}/pies.html | ||
529 | pies chapter ${PIES}/html_chapter/ | ||
530 | pies section ${PIES}/html_section/ | ||
531 | pies node ${PIES}/html_node/ | ||
532 | |||
533 | plotutils mono ${GS}/plotutils/manual/en/plotutils.html | ||
534 | plotutils node ${GS}/plotutils/manual/en/html_node/ | ||
535 | |||
536 | proxyknife mono ${GS}/proxyknife/manual/proxyknife.html | ||
537 | proxyknife node ${GS}/proxyknife/manual/html_node/ | ||
538 | |||
539 | pspp mono ${GS}/pspp/manual/pspp.html | ||
540 | pspp node ${GS}/pspp/manual/html_node/ | ||
541 | |||
542 | pyconfigure mono ${GS}/pyconfigure/manual/pyconfigure.html | ||
543 | pyconfigure node ${GS}/pyconfigure/manual/html_node/ | ||
544 | |||
545 | R = http://cran.r-project.org/doc/manuals | ||
546 | R-intro mono ${R}/R-intro.html | ||
547 | R-lang mono ${R}/R-lang.html | ||
548 | R-exts mono ${R}/R-exts.html | ||
549 | R-data mono ${R}/R-data.html | ||
550 | R-admin mono ${R}/R-admin.html | ||
551 | R-ints mono ${R}/R-ints.html | ||
552 | |||
553 | rcs mono ${GS}/rcs/manual/rcs.html | ||
554 | rcs node ${GS}/rcs/manual/html_node/ | ||
555 | |||
556 | READLINE = http://cnswww.cns.cwru.edu/php/chet/readline | ||
557 | readline mono ${READLINE}/readline.html | ||
558 | rluserman mono ${READLINE}/rluserman.html | ||
559 | history mono ${READLINE}/history.html | ||
560 | |||
561 | recode mono http://recode.progiciels-bpi.ca/manual/index.html | ||
562 | |||
563 | recutils mono ${GS}/recutils/manual/recutils.html | ||
564 | recutils node ${GS}/recutils/manual/html_node/ | ||
565 | |||
566 | reftex mono ${GS}/auctex/manual/reftex.html | ||
567 | reftex node ${GS}/auctex/manual/reftex/ | ||
568 | |||
569 | remotecontrol mono ${GS}/remotecontrol/manual/remotecontrol.html | ||
570 | remotecontrol node ${GS}/remotecontrol/manual/html_node/ | ||
571 | |||
572 | rottlog mono ${GS}/rottlog/manual/rottlog.html | ||
573 | rottlog node ${GS}/rottlog/manual/html_node/ | ||
574 | |||
575 | RUSH = http://www.gnu.org.ua/software/rush/manual | ||
576 | rush mono ${RUSH}/rush.html | ||
577 | rush chapter ${RUSH}/html_chapter/ | ||
578 | rush section ${RUSH}/html_section/ | ||
579 | rush node ${RUSH}/html_node/ | ||
580 | |||
581 | screen mono ${GS}/screen/manual/screen.html | ||
582 | screen node ${GS}/screen/manual/html_node/ | ||
583 | |||
584 | sed mono ${GS}/sed/manual/sed.html | ||
585 | sed node ${GS}/sed/manual/html_node/ | ||
586 | |||
587 | sharutils mono ${GS}/sharutils/manual/html_mono/sharutils.html | ||
588 | sharutils chapter ${GS}/sharutils/manual/html_chapter/ | ||
589 | sharutils node ${GS}/sharutils/manual/html_node/ | ||
590 | |||
591 | shepherd mono ${GS}/shepherd/manual/shepherd.html | ||
592 | shepherd node ${GS}/shepherd/manual/html_node/ | ||
593 | |||
594 | # can't use mono files since they have generic names | ||
595 | SMALLTALK = ${GS}/smalltalk | ||
596 | smalltalk node ${SMALLTALK}/manual/html_node/ | ||
597 | smalltalk-base node ${SMALLTALK}/manual-base/html_node/ | ||
598 | smalltalk-libs node ${SMALLTALK}/manual-libs/html_node/ | ||
599 | |||
600 | sourceinstall mono ${GS}/sourceinstall/manual/sourceinstall.html | ||
601 | sourceinstall node ${GS}/sourceinstall/manual/html_node/ | ||
602 | |||
603 | sqltutor mono ${GS}/sqltutor/manual/sqltutor.html | ||
604 | sqltutor node ${GS}/sqltutor/manual/html_node/ | ||
605 | |||
606 | src-highlite mono ${GS}/src-highlite/source-highlight.html | ||
607 | |||
608 | swbis mono ${GS}/swbis/manual.html | ||
609 | |||
610 | tar mono ${GS}/tar/manual/tar.html | ||
611 | tar chapter ${GS}/tar/manual/html_chapter/ | ||
612 | tar section ${GS}/tar/manual/html_section/ | ||
613 | tar node ${GS}/autoconf/manual/html_node/ | ||
614 | |||
615 | teseq mono ${GS}/teseq/teseq.html | ||
616 | teseq node ${GS}/teseq/html_node/ | ||
617 | |||
618 | TEXINFO = ${GS}/texinfo/manual | ||
619 | texinfo mono ${TEXINFO}/texinfo/texinfo.html | ||
620 | texinfo node ${TEXINFO}/texinfo/html_node/ | ||
621 | # | ||
622 | info mono ${TEXINFO}/info/info.html | ||
623 | info node ${TEXINFO}/info/html_node/ | ||
624 | # | ||
625 | info-stnd mono ${TEXINFO}/info-stnd/info-stnd.html | ||
626 | info-stnd node ${TEXINFO}/info-stnd/html_node/ | ||
627 | |||
628 | thales node ${GS}/thales/manual/ | ||
629 | |||
630 | units mono ${GS}/units/manual/units.html | ||
631 | units node ${GS}/units/manual/html_node/ | ||
632 | |||
633 | vc-dwim mono ${GS}/vc-dwim/manual/vc-dwim.html | ||
634 | vc-dwim node ${GS}/vc-dwim/manual/html_node/ | ||
635 | |||
636 | wdiff mono ${GS}/wdiff/manual/wdiff.html | ||
637 | wdiff node ${GS}/wdiff/manual/html_node/ | ||
638 | |||
639 | websocket4j mono ${GS}/websocket4j/manual/websocket4j.html | ||
640 | websocket4j node ${GS}/websocket4j/manual/html_node/ | ||
641 | |||
642 | wget mono ${GS}/wget/manual/wget.html | ||
643 | wget node ${GS}/wget/manual/html_node/ | ||
644 | |||
645 | xboard mono ${GS}/xboard/manual/xboard.html | ||
646 | xboard node ${GS}/xboard/manual/html_node/ | ||
647 | |||
648 | # emacs-page | ||
649 | # Free TeX-related Texinfo manuals on tug.org. | ||
650 | |||
651 | T = http://tug.org/texinfohtml | ||
652 | |||
653 | dvipng mono ${T}/dvipng.html | ||
654 | dvips mono ${T}/dvips.html | ||
655 | eplain mono ${T}/eplain.html | ||
656 | kpathsea mono ${T}/kpathsea.html | ||
657 | latex2e mono ${T}/latex2e.html | ||
658 | tlbuild mono ${T}/tlbuild.html | ||
659 | web2c mono ${T}/web2c.html | ||
660 | |||
661 | |||
662 | # Local Variables: | ||
663 | # eval: (add-hook 'write-file-hooks 'time-stamp) | ||
664 | # time-stamp-start: "htmlxrefversion=" | ||
665 | # time-stamp-format: "%:y-%02m-%02d.%02H" | ||
666 | # time-stamp-time-zone: "UTC" | ||
667 | # time-stamp-end: "; # UTC" | ||
668 | # End: | ||
diff --git a/doc/documentation/images/daemon_lego_block.png b/doc/documentation/images/daemon_lego_block.png new file mode 100644 index 000000000..5a088b532 --- /dev/null +++ b/doc/documentation/images/daemon_lego_block.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/daemon_lego_block.svg b/doc/documentation/images/daemon_lego_block.svg new file mode 100644 index 000000000..38ad90d13 --- /dev/null +++ b/doc/documentation/images/daemon_lego_block.svg | |||
@@ -0,0 +1,126 @@ | |||
1 | <?xml version="1.0" encoding="UTF-8" standalone="no"?> | ||
2 | <!-- Created with Inkscape (http://www.inkscape.org/) --> | ||
3 | |||
4 | <svg | ||
5 | xmlns:dc="http://purl.org/dc/elements/1.1/" | ||
6 | xmlns:cc="http://creativecommons.org/ns#" | ||
7 | xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" | ||
8 | xmlns:svg="http://www.w3.org/2000/svg" | ||
9 | xmlns="http://www.w3.org/2000/svg" | ||
10 | xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" | ||
11 | xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape" | ||
12 | width="744.09448819" | ||
13 | height="1052.3622047" | ||
14 | id="svg6781" | ||
15 | version="1.1" | ||
16 | inkscape:version="0.48.2 r9819" | ||
17 | sodipodi:docname="New document 58"> | ||
18 | <defs | ||
19 | id="defs6783" /> | ||
20 | <sodipodi:namedview | ||
21 | id="base" | ||
22 | pagecolor="#ffffff" | ||
23 | bordercolor="#666666" | ||
24 | borderopacity="1.0" | ||
25 | inkscape:pageopacity="0.0" | ||
26 | inkscape:pageshadow="2" | ||
27 | inkscape:zoom="0.35" | ||
28 | inkscape:cx="375" | ||
29 | inkscape:cy="520" | ||
30 | inkscape:document-units="px" | ||
31 | inkscape:current-layer="layer1" | ||
32 | showgrid="false" | ||
33 | inkscape:window-width="1366" | ||
34 | inkscape:window-height="721" | ||
35 | inkscape:window-x="-2" | ||
36 | inkscape:window-y="-3" | ||
37 | inkscape:window-maximized="1" /> | ||
38 | <metadata | ||
39 | id="metadata6786"> | ||
40 | <rdf:RDF> | ||
41 | <cc:Work | ||
42 | rdf:about=""> | ||
43 | <dc:format>image/svg+xml</dc:format> | ||
44 | <dc:type | ||
45 | rdf:resource="http://purl.org/dc/dcmitype/StillImage" /> | ||
46 | <dc:title></dc:title> | ||
47 | </cc:Work> | ||
48 | </rdf:RDF> | ||
49 | </metadata> | ||
50 | <g | ||
51 | inkscape:label="Layer 1" | ||
52 | inkscape:groupmode="layer" | ||
53 | id="layer1"> | ||
54 | <g | ||
55 | transform="translate(-4.5298577,-148.04661)" | ||
56 | id="g6746"> | ||
57 | <path | ||
58 | style="fill:#5fd38d;fill-opacity:1;stroke:#faf6a2;stroke-width:1.99014676;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
59 | d="m 183.84284,595.7683 350.8064,0 0,202.04036 -350.8064,0 z" | ||
60 | id="path6693" | ||
61 | inkscape:connector-curvature="0" /> | ||
62 | <rect | ||
63 | style="fill:#ffffff;fill-opacity:1;stroke:#faf6a2;stroke-width:2.22747946;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
64 | id="rect6695" | ||
65 | width="66.670067" | ||
66 | height="75.18058" | ||
67 | x="223.74881" | ||
68 | y="737.19458" /> | ||
69 | <rect | ||
70 | y="737.19458" | ||
71 | x="331.83514" | ||
72 | height="67.323441" | ||
73 | width="66.670067" | ||
74 | id="rect6697" | ||
75 | style="fill:#ffffff;fill-opacity:1;stroke:#faf6a2;stroke-width:2.10787106;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
76 | <rect | ||
77 | style="fill:#ffffff;fill-opacity:1;stroke:#faf6a2;stroke-width:2.06117821;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
78 | id="rect6699" | ||
79 | width="66.670067" | ||
80 | height="64.373825" | ||
81 | x="434.8707" | ||
82 | y="737.19458" /> | ||
83 | <path | ||
84 | style="fill:#37c871;fill-opacity:1;stroke:#faf6a2;stroke-width:0.98368376;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
85 | d="m 223.60976,736.21851 67.23534,0.38374 0,23.63648 -67.23534,37.13818 z" | ||
86 | id="path6701" | ||
87 | inkscape:connector-curvature="0" | ||
88 | sodipodi:nodetypes="ccccc" /> | ||
89 | <path | ||
90 | sodipodi:nodetypes="ccccc" | ||
91 | inkscape:connector-curvature="0" | ||
92 | id="path6703" | ||
93 | d="m 331.69608,736.21851 67.23534,0.3894 0,23.98466 -67.23534,37.68524 z" | ||
94 | style="fill:#37c871;fill-opacity:1;stroke:#faf6a2;stroke-width:0.99090236;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
95 | <path | ||
96 | style="fill:#37c871;fill-opacity:1;stroke:#faf6a2;stroke-width:0.98368376;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
97 | d="m 434.73164,736.21851 67.23534,0.38374 0,23.63648 -67.23534,37.13818 z" | ||
98 | id="path6705" | ||
99 | inkscape:connector-curvature="0" | ||
100 | sodipodi:nodetypes="ccccc" /> | ||
101 | <path | ||
102 | style="fill:#37c871;fill-opacity:1;stroke:#faf6a2;stroke-width:1.92068994;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
103 | d="m 533.72659,595.02309 56.12366,-29.34622 -1.01015,190.24271 -55.11351,41.45733 z" | ||
104 | id="path6707" | ||
105 | inkscape:connector-curvature="0" | ||
106 | sodipodi:nodetypes="ccccc" /> | ||
107 | <path | ||
108 | style="fill:#37c871;fill-opacity:1;stroke:#faf6a2;stroke-width:1.99424875;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
109 | d="m 245.46708,566.47881 345.46203,-1.01015 -56.56854,31.31472 -349.50264,-1.01014 z" | ||
110 | id="path6709" | ||
111 | inkscape:connector-curvature="0" | ||
112 | sodipodi:nodetypes="ccccc" /> | ||
113 | <text | ||
114 | sodipodi:linespacing="125%" | ||
115 | id="text6715" | ||
116 | y="677.59558" | ||
117 | x="234.35539" | ||
118 | style="font-size:36px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
119 | xml:space="preserve"><tspan | ||
120 | y="677.59558" | ||
121 | x="234.35539" | ||
122 | id="tspan6717" | ||
123 | sodipodi:role="line">User Interface</tspan></text> | ||
124 | </g> | ||
125 | </g> | ||
126 | </svg> | ||
diff --git a/doc/documentation/images/gnunet-0-10-peerinfo.png b/doc/documentation/images/gnunet-0-10-peerinfo.png new file mode 100644 index 000000000..c5e711aff --- /dev/null +++ b/doc/documentation/images/gnunet-0-10-peerinfo.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-fs-gtk-0-10-star-tab.png b/doc/documentation/images/gnunet-fs-gtk-0-10-star-tab.png new file mode 100644 index 000000000..d7993cc46 --- /dev/null +++ b/doc/documentation/images/gnunet-fs-gtk-0-10-star-tab.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-download-area.png b/doc/documentation/images/gnunet-gtk-0-10-download-area.png new file mode 100644 index 000000000..8500d46c9 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-download-area.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-fs-menu.png b/doc/documentation/images/gnunet-gtk-0-10-fs-menu.png new file mode 100644 index 000000000..dc20c45a9 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-fs-menu.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-fs-publish-editing.png b/doc/documentation/images/gnunet-gtk-0-10-fs-publish-editing.png new file mode 100644 index 000000000..6f9f75ea6 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-fs-publish-editing.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-fs-publish-select.png b/doc/documentation/images/gnunet-gtk-0-10-fs-publish-select.png new file mode 100644 index 000000000..50672e379 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-fs-publish-select.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-fs-publish-with-file.png b/doc/documentation/images/gnunet-gtk-0-10-fs-publish-with-file.png new file mode 100644 index 000000000..b46542563 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-fs-publish-with-file.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-fs-publish-with-file_0.png b/doc/documentation/images/gnunet-gtk-0-10-fs-publish-with-file_0.png new file mode 100644 index 000000000..b46542563 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-fs-publish-with-file_0.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-fs-publish.png b/doc/documentation/images/gnunet-gtk-0-10-fs-publish.png new file mode 100644 index 000000000..033b38fa5 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-fs-publish.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-fs-published.png b/doc/documentation/images/gnunet-gtk-0-10-fs-published.png new file mode 100644 index 000000000..fbd3dd6a3 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-fs-published.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-fs-search.png b/doc/documentation/images/gnunet-gtk-0-10-fs-search.png new file mode 100644 index 000000000..bb64ab92e --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-fs-search.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-fs.png b/doc/documentation/images/gnunet-gtk-0-10-fs.png new file mode 100644 index 000000000..c7a294878 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-fs.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-gns-a-done.png b/doc/documentation/images/gnunet-gtk-0-10-gns-a-done.png new file mode 100644 index 000000000..f8231b3a6 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-gns-a-done.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-gns-a.png b/doc/documentation/images/gnunet-gtk-0-10-gns-a.png new file mode 100644 index 000000000..39858d72c --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-gns-a.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-gns.png b/doc/documentation/images/gnunet-gtk-0-10-gns.png new file mode 100644 index 000000000..c71a2bd7b --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-gns.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-identity.png b/doc/documentation/images/gnunet-gtk-0-10-identity.png new file mode 100644 index 000000000..d0b426098 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-identity.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-search-selected.png b/doc/documentation/images/gnunet-gtk-0-10-search-selected.png new file mode 100644 index 000000000..da1ad4d31 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-search-selected.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10-traffic.png b/doc/documentation/images/gnunet-gtk-0-10-traffic.png new file mode 100644 index 000000000..76458f717 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10-traffic.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-gtk-0-10.png b/doc/documentation/images/gnunet-gtk-0-10.png new file mode 100644 index 000000000..3615849a7 --- /dev/null +++ b/doc/documentation/images/gnunet-gtk-0-10.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-namestore-gtk-phone.png b/doc/documentation/images/gnunet-namestore-gtk-phone.png new file mode 100644 index 000000000..3bb859629 --- /dev/null +++ b/doc/documentation/images/gnunet-namestore-gtk-phone.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-namestore-gtk-vpn.png b/doc/documentation/images/gnunet-namestore-gtk-vpn.png new file mode 100644 index 000000000..c716729ba --- /dev/null +++ b/doc/documentation/images/gnunet-namestore-gtk-vpn.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-setup-exit.png b/doc/documentation/images/gnunet-setup-exit.png new file mode 100644 index 000000000..66bd972bc --- /dev/null +++ b/doc/documentation/images/gnunet-setup-exit.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-tutorial-service.png b/doc/documentation/images/gnunet-tutorial-service.png new file mode 100644 index 000000000..6daed2f35 --- /dev/null +++ b/doc/documentation/images/gnunet-tutorial-service.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/gnunet-tutorial-system.png b/doc/documentation/images/gnunet-tutorial-system.png new file mode 100644 index 000000000..8b54e16cf --- /dev/null +++ b/doc/documentation/images/gnunet-tutorial-system.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/iceweasel-preferences.png b/doc/documentation/images/iceweasel-preferences.png new file mode 100644 index 000000000..e62c2c4d9 --- /dev/null +++ b/doc/documentation/images/iceweasel-preferences.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/iceweasel-proxy.png b/doc/documentation/images/iceweasel-proxy.png new file mode 100644 index 000000000..9caad4508 --- /dev/null +++ b/doc/documentation/images/iceweasel-proxy.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/lego_stack.svg b/doc/documentation/images/lego_stack.svg new file mode 100644 index 000000000..a0e8017c3 --- /dev/null +++ b/doc/documentation/images/lego_stack.svg | |||
@@ -0,0 +1,737 @@ | |||
1 | <?xml version="1.0" encoding="UTF-8" standalone="no"?> | ||
2 | <!-- Created with Inkscape (http://www.inkscape.org/) --> | ||
3 | |||
4 | <svg | ||
5 | xmlns:osb="http://www.openswatchbook.org/uri/2009/osb" | ||
6 | xmlns:dc="http://purl.org/dc/elements/1.1/" | ||
7 | xmlns:cc="http://creativecommons.org/ns#" | ||
8 | xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" | ||
9 | xmlns:svg="http://www.w3.org/2000/svg" | ||
10 | xmlns="http://www.w3.org/2000/svg" | ||
11 | xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" | ||
12 | xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape" | ||
13 | width="744.09448819" | ||
14 | height="1052.3622047" | ||
15 | id="svg2" | ||
16 | version="1.1" | ||
17 | inkscape:version="0.48.1 r9760" | ||
18 | sodipodi:docname="System.svg"> | ||
19 | <defs | ||
20 | id="defs4"> | ||
21 | <linearGradient | ||
22 | id="linearGradient6602"> | ||
23 | <stop | ||
24 | style="stop-color:#df8060;stop-opacity:1;" | ||
25 | offset="0" | ||
26 | id="stop6604" /> | ||
27 | <stop | ||
28 | style="stop-color:#df8002;stop-opacity:0;" | ||
29 | offset="1" | ||
30 | id="stop6606" /> | ||
31 | </linearGradient> | ||
32 | <linearGradient | ||
33 | id="linearGradient4392" | ||
34 | osb:paint="solid"> | ||
35 | <stop | ||
36 | style="stop-color:#faf6a6;stop-opacity:1;" | ||
37 | offset="0" | ||
38 | id="stop4394" /> | ||
39 | </linearGradient> | ||
40 | <inkscape:perspective | ||
41 | sodipodi:type="inkscape:persp3d" | ||
42 | inkscape:vp_x="883.99395 : 559.99673 : 1" | ||
43 | inkscape:vp_y="13.319386 : 993.87659 : 0" | ||
44 | inkscape:vp_z="285.3157 : 504.79962 : 1" | ||
45 | inkscape:persp3d-origin="481.39556 : 281.96355 : 1" | ||
46 | id="perspective3070" /> | ||
47 | <inkscape:perspective | ||
48 | sodipodi:type="inkscape:persp3d" | ||
49 | inkscape:vp_x="76.097926 : 349.87282 : 1" | ||
50 | inkscape:vp_y="-13.319386 : 979.366 : 0" | ||
51 | inkscape:vp_z="752.55793 : 376.31441 : 1" | ||
52 | inkscape:persp3d-origin="373.64045 : 350.98006 : 1" | ||
53 | id="perspective3012" /> | ||
54 | </defs> | ||
55 | <sodipodi:namedview | ||
56 | id="base" | ||
57 | pagecolor="#ffffff" | ||
58 | bordercolor="#666666" | ||
59 | borderopacity="1.0" | ||
60 | inkscape:pageopacity="0.0" | ||
61 | inkscape:pageshadow="2" | ||
62 | inkscape:zoom="0.98994949" | ||
63 | inkscape:cx="322.06882" | ||
64 | inkscape:cy="568.82291" | ||
65 | inkscape:document-units="px" | ||
66 | inkscape:current-layer="layer1" | ||
67 | showgrid="false" | ||
68 | inkscape:window-width="846" | ||
69 | inkscape:window-height="963" | ||
70 | inkscape:window-x="59" | ||
71 | inkscape:window-y="0" | ||
72 | inkscape:window-maximized="0" /> | ||
73 | <metadata | ||
74 | id="metadata7"> | ||
75 | <rdf:RDF> | ||
76 | <cc:Work | ||
77 | rdf:about=""> | ||
78 | <dc:format>image/svg+xml</dc:format> | ||
79 | <dc:type | ||
80 | rdf:resource="http://purl.org/dc/dcmitype/StillImage" /> | ||
81 | <dc:title /> | ||
82 | </cc:Work> | ||
83 | </rdf:RDF> | ||
84 | </metadata> | ||
85 | <g | ||
86 | inkscape:label="Layer 1" | ||
87 | inkscape:groupmode="layer" | ||
88 | id="layer1"> | ||
89 | <text | ||
90 | xml:space="preserve" | ||
91 | style="font-size:40px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
92 | x="352.03815" | ||
93 | y="-190.12544" | ||
94 | id="text6623" | ||
95 | sodipodi:linespacing="125%"><tspan | ||
96 | sodipodi:role="line" | ||
97 | id="tspan6625" | ||
98 | x="352.03815" | ||
99 | y="-190.12544" /></text> | ||
100 | <text | ||
101 | xml:space="preserve" | ||
102 | style="font-size:40px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
103 | x="338.40109" | ||
104 | y="-300.73715" | ||
105 | id="text6627" | ||
106 | sodipodi:linespacing="125%"><tspan | ||
107 | sodipodi:role="line" | ||
108 | id="tspan6629" | ||
109 | x="338.40109" | ||
110 | y="-300.73715" /></text> | ||
111 | <g | ||
112 | style="font-size:24px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
113 | id="text6643" /> | ||
114 | <text | ||
115 | xml:space="preserve" | ||
116 | style="font-size:24px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
117 | x="71.720833" | ||
118 | y="95.747719" | ||
119 | id="text6648" | ||
120 | sodipodi:linespacing="125%"><tspan | ||
121 | sodipodi:role="line" | ||
122 | id="tspan6650" | ||
123 | x="71.720833" | ||
124 | y="95.747719" /></text> | ||
125 | <text | ||
126 | xml:space="preserve" | ||
127 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
128 | x="262.63965" | ||
129 | y="666.48389" | ||
130 | id="text6711" | ||
131 | sodipodi:linespacing="125%"><tspan | ||
132 | sodipodi:role="line" | ||
133 | id="tspan6713" | ||
134 | x="262.63965" | ||
135 | y="666.48389" /></text> | ||
136 | <path | ||
137 | inkscape:connector-curvature="0" | ||
138 | id="path3506" | ||
139 | d="m 198.00647,673.76257 236.93358,0 0,158.2919 -236.93358,0 z" | ||
140 | style="fill:#000000;fill-opacity:1;stroke:#faf6a2;stroke-width:1.44768786;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
141 | <path | ||
142 | sodipodi:nodetypes="ccccc" | ||
143 | inkscape:connector-curvature="0" | ||
144 | id="path3432" | ||
145 | d="m 169.32669,654.90334 464.83332,-2.26992 -33.76593,25.73079 -483.97287,-0.12904 z" | ||
146 | style="fill:#deaa87;fill-opacity:1;stroke:#faf6a2;stroke-width:2.18398547;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
147 | <rect | ||
148 | style="fill:#000000;fill-opacity:1;stroke:#59000c;stroke-width:1.35822594;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0.48230088;stroke-dasharray:none;stroke-dashoffset:0" | ||
149 | id="rect3416" | ||
150 | width="28.495705" | ||
151 | height="172.2845" | ||
152 | x="464.19418" | ||
153 | y="518.96954" /> | ||
154 | <rect | ||
155 | style="fill:#000000;fill-opacity:1;stroke:#59000c;stroke-width:1.36876941;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0.48230088;stroke-dasharray:none;stroke-dashoffset:0" | ||
156 | id="rect3414" | ||
157 | width="34.729141" | ||
158 | height="170.67587" | ||
159 | x="340.86124" | ||
160 | y="517.93475" /> | ||
161 | <path | ||
162 | style="fill:#deaa87;fill-opacity:1;stroke:#faf6a2;stroke-width:2.04969239;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
163 | d="m 246.8138,499.06358 386.50295,-0.94821 -41.88736,26.04231 -413.96081,0 z" | ||
164 | id="rect6568-0" | ||
165 | inkscape:connector-curvature="0" | ||
166 | sodipodi:nodetypes="ccccc" /> | ||
167 | <path | ||
168 | style="fill:#ffdd55;fill-opacity:1;stroke:#faf6a2;stroke-width:1.49989259;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
169 | d="m 276.05867,399.52042 323.05541,0 0,124.61741 -323.05541,0 z" | ||
170 | id="rect5973" | ||
171 | inkscape:connector-curvature="0" /> | ||
172 | <path | ||
173 | style="fill:#ffcc00;fill-opacity:1;stroke:#faf6a2;stroke-width:1.19094384;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
174 | d="m 599.16863,399.06078 34.35465,-18.10059 0,117.34068 -34.35465,25.57066 z" | ||
175 | id="rect6542" | ||
176 | inkscape:connector-curvature="0" | ||
177 | sodipodi:nodetypes="ccccc" /> | ||
178 | <rect | ||
179 | style="fill:#c87137;fill-opacity:1;stroke:#c48069;stroke-width:1.50087094;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
180 | id="rect6557" | ||
181 | width="322.88623" | ||
182 | height="30.529778" | ||
183 | x="276.67755" | ||
184 | y="368.99368" /> | ||
185 | <path | ||
186 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:0.50882494;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
187 | d="m 598.94047,368.99367 34.58281,-16.82253 0,28.66061 -34.58281,18.06864 z" | ||
188 | id="rect6561" | ||
189 | inkscape:connector-curvature="0" | ||
190 | sodipodi:nodetypes="ccccc" /> | ||
191 | <path | ||
192 | sodipodi:nodetypes="ccccc" | ||
193 | inkscape:connector-curvature="0" | ||
194 | id="path6564" | ||
195 | d="m 598.94047,369.07046 34.30741,-17.12981 0,29.18412 -34.30741,18.39868 z" | ||
196 | style="fill:#c87137;fill-opacity:1;stroke:#faf6a2;stroke-width:0.51140249;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
197 | inkscape:transform-center-x="-70.147578" | ||
198 | inkscape:transform-center-y="15.429055" /> | ||
199 | <path | ||
200 | style="fill:#d38d5f;fill-opacity:1;stroke:#faf6a2;stroke-width:1.47079194;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
201 | d="m 330.2508,353.23478 302.87005,-0.62306 -38.33414,16.82253 -318.87597,0 z" | ||
202 | id="rect6568" | ||
203 | inkscape:connector-curvature="0" | ||
204 | sodipodi:nodetypes="ccccc" /> | ||
205 | <text | ||
206 | xml:space="preserve" | ||
207 | style="font-size:22.32217598px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
208 | x="391.63083" | ||
209 | y="461.858" | ||
210 | id="text6656" | ||
211 | sodipodi:linespacing="125%" | ||
212 | transform="scale(1.0052948,0.9947331)"><tspan | ||
213 | sodipodi:role="line" | ||
214 | id="tspan6658" | ||
215 | x="391.63083" | ||
216 | y="461.858">Service</tspan></text> | ||
217 | <path | ||
218 | sodipodi:nodetypes="ccccc" | ||
219 | inkscape:connector-curvature="0" | ||
220 | id="path6707" | ||
221 | d="m 598.75503,244.83802 34.98432,-18.10059 0.26082,125.2709 -35.24514,17.64044 z" | ||
222 | style="fill:#37c871;fill-opacity:1;stroke:#faf6a2;stroke-width:1.19094384;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
223 | <path | ||
224 | sodipodi:nodetypes="ccccc" | ||
225 | inkscape:connector-curvature="0" | ||
226 | id="path6709" | ||
227 | d="m 419.07032,228.1132 214.71185,-1.24611 -34.63196,19.9378 L 381.29,246.18184 z" | ||
228 | style="fill:#37c871;fill-opacity:1;stroke:#faf6a2;stroke-width:1.23655474;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
229 | <rect | ||
230 | style="fill:#5fd38d;fill-opacity:1;stroke:#c48069;stroke-width:1.23640049;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
231 | id="rect7224" | ||
232 | width="217.86653" | ||
233 | height="122.74216" | ||
234 | x="381.70358" | ||
235 | y="246.25151" /> | ||
236 | <text | ||
237 | xml:space="preserve" | ||
238 | style="font-size:22.32217598px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
239 | x="409.16376" | ||
240 | y="302.05649" | ||
241 | id="text6715" | ||
242 | sodipodi:linespacing="125%" | ||
243 | transform="scale(1.0052948,0.9947331)"><tspan | ||
244 | sodipodi:role="line" | ||
245 | id="tspan6717" | ||
246 | x="409.16376" | ||
247 | y="302.05649">User Interface</tspan></text> | ||
248 | <g | ||
249 | id="g7219" | ||
250 | transform="matrix(0.62334353,0,0,0.61679464,281.18563,257.70936)"> | ||
251 | <rect | ||
252 | y="119.99139" | ||
253 | x="198.49498" | ||
254 | height="60.609154" | ||
255 | width="66.670067" | ||
256 | id="rect6571" | ||
257 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
258 | <text | ||
259 | sodipodi:linespacing="125%" | ||
260 | id="text6631" | ||
261 | y="160.39748" | ||
262 | x="206.07112" | ||
263 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
264 | xml:space="preserve"><tspan | ||
265 | y="160.39748" | ||
266 | x="206.07112" | ||
267 | id="tspan6633" | ||
268 | sodipodi:role="line">API</tspan></text> | ||
269 | </g> | ||
270 | <g | ||
271 | transform="matrix(0.62334353,0,0,0.61679464,344.78251,257.70936)" | ||
272 | id="g7226"> | ||
273 | <rect | ||
274 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
275 | id="rect7228" | ||
276 | width="66.670067" | ||
277 | height="60.609154" | ||
278 | x="198.49498" | ||
279 | y="119.99139" /> | ||
280 | <text | ||
281 | xml:space="preserve" | ||
282 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
283 | x="206.07112" | ||
284 | y="160.39748" | ||
285 | id="text7230" | ||
286 | sodipodi:linespacing="125%"><tspan | ||
287 | sodipodi:role="line" | ||
288 | id="tspan7232" | ||
289 | x="206.07112" | ||
290 | y="160.39748">API</tspan></text> | ||
291 | </g> | ||
292 | <g | ||
293 | id="g7234" | ||
294 | transform="matrix(0.62334353,0,0,0.61679464,409.3239,257.70936)"> | ||
295 | <rect | ||
296 | y="119.99139" | ||
297 | x="198.49498" | ||
298 | height="60.609154" | ||
299 | width="66.670067" | ||
300 | id="rect7236" | ||
301 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
302 | <text | ||
303 | sodipodi:linespacing="125%" | ||
304 | id="text7238" | ||
305 | y="160.39748" | ||
306 | x="206.07112" | ||
307 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
308 | xml:space="preserve"><tspan | ||
309 | y="160.39748" | ||
310 | x="206.07112" | ||
311 | id="tspan7240" | ||
312 | sodipodi:role="line">API</tspan></text> | ||
313 | </g> | ||
314 | <g | ||
315 | transform="matrix(0.62334353,0,0,0.61679464,175.75806,412.85048)" | ||
316 | id="g7242"> | ||
317 | <rect | ||
318 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
319 | id="rect7244" | ||
320 | width="66.670067" | ||
321 | height="60.609154" | ||
322 | x="198.49498" | ||
323 | y="119.99139" /> | ||
324 | <text | ||
325 | xml:space="preserve" | ||
326 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
327 | x="206.07112" | ||
328 | y="160.39748" | ||
329 | id="text7246" | ||
330 | sodipodi:linespacing="125%"><tspan | ||
331 | sodipodi:role="line" | ||
332 | id="tspan7248" | ||
333 | x="206.07112" | ||
334 | y="160.39748">API</tspan></text> | ||
335 | </g> | ||
336 | <g | ||
337 | id="g7250" | ||
338 | transform="matrix(0.62334353,0,0,0.61679464,240.79871,413.29105)"> | ||
339 | <rect | ||
340 | y="119.99139" | ||
341 | x="198.49498" | ||
342 | height="60.609154" | ||
343 | width="66.670067" | ||
344 | id="rect7252" | ||
345 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
346 | <text | ||
347 | sodipodi:linespacing="125%" | ||
348 | id="text7254" | ||
349 | y="160.39748" | ||
350 | x="206.07112" | ||
351 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
352 | xml:space="preserve"><tspan | ||
353 | y="160.39748" | ||
354 | x="206.07112" | ||
355 | id="tspan7256" | ||
356 | sodipodi:role="line">API</tspan></text> | ||
357 | </g> | ||
358 | <g | ||
359 | transform="matrix(0.62334353,0,0,0.61679464,303.79756,412.40991)" | ||
360 | id="g7258"> | ||
361 | <rect | ||
362 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
363 | id="rect7260" | ||
364 | width="66.670067" | ||
365 | height="60.609154" | ||
366 | x="198.49498" | ||
367 | y="119.99139" /> | ||
368 | <text | ||
369 | xml:space="preserve" | ||
370 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
371 | x="206.07112" | ||
372 | y="160.39748" | ||
373 | id="text7262" | ||
374 | sodipodi:linespacing="125%"><tspan | ||
375 | sodipodi:role="line" | ||
376 | id="tspan7264" | ||
377 | x="206.07112" | ||
378 | y="160.39748">API</tspan></text> | ||
379 | </g> | ||
380 | <g | ||
381 | id="g7266" | ||
382 | transform="matrix(0.62334353,0,0,0.61679464,369.88148,412.40991)"> | ||
383 | <rect | ||
384 | y="119.99139" | ||
385 | x="198.49498" | ||
386 | height="60.609154" | ||
387 | width="66.670067" | ||
388 | id="rect7268" | ||
389 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
390 | <text | ||
391 | sodipodi:linespacing="125%" | ||
392 | id="text7270" | ||
393 | y="160.39748" | ||
394 | x="206.07112" | ||
395 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
396 | xml:space="preserve"><tspan | ||
397 | y="160.39748" | ||
398 | x="206.07112" | ||
399 | id="tspan7272" | ||
400 | sodipodi:role="line">API</tspan></text> | ||
401 | </g> | ||
402 | <path | ||
403 | style="fill:#ffeeaa;fill-opacity:1;stroke:#faf6a2;stroke-width:0.91879815;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
404 | d="m 478.56081,554.09281 121.22633,0 0,124.61741 -121.22633,0 z" | ||
405 | id="rect5973-1" | ||
406 | inkscape:connector-curvature="0" /> | ||
407 | <g | ||
408 | transform="matrix(0.62334353,0,0,0.61679464,422.424,566.60858)" | ||
409 | id="g3474"> | ||
410 | <rect | ||
411 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
412 | id="rect3476" | ||
413 | width="66.670067" | ||
414 | height="60.609154" | ||
415 | x="198.49498" | ||
416 | y="119.99139" /> | ||
417 | <text | ||
418 | xml:space="preserve" | ||
419 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
420 | x="206.07112" | ||
421 | y="160.39748" | ||
422 | id="text3478" | ||
423 | sodipodi:linespacing="125%"><tspan | ||
424 | sodipodi:role="line" | ||
425 | id="tspan3480" | ||
426 | x="206.07112" | ||
427 | y="160.39748">API</tspan></text> | ||
428 | </g> | ||
429 | <path | ||
430 | style="fill:#ffe680;fill-opacity:1;stroke:#faf6a2;stroke-width:1.18771458;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
431 | d="m 599.60339,554.02055 33.72575,-29.55535 0.88568,128.35487 -34.61143,26.01123 z" | ||
432 | id="rect6542-8" | ||
433 | inkscape:connector-curvature="0" | ||
434 | sodipodi:nodetypes="ccccc" /> | ||
435 | <path | ||
436 | sodipodi:nodetypes="ccccc" | ||
437 | inkscape:connector-curvature="0" | ||
438 | id="path6564-2" | ||
439 | d="m 598.92998,524.03024 34.30741,-25.94116 0,26.5407 -34.30741,29.85344 z" | ||
440 | style="fill:#d38d5f;fill-opacity:1;stroke:#faf6a2;stroke-width:0.51140249;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
441 | inkscape:transform-center-x="-70.147578" | ||
442 | inkscape:transform-center-y="15.429055" /> | ||
443 | <path | ||
444 | inkscape:transform-center-y="15.492457" | ||
445 | inkscape:transform-center-x="-70.147578" | ||
446 | style="fill:#c87137;fill-opacity:1;stroke:#faf6a2;stroke-width:0.51245213;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
447 | d="m 598.92998,524.13683 34.30741,-26.04775 0,26.64977 -34.30741,29.97611 z" | ||
448 | id="path3402" | ||
449 | inkscape:connector-curvature="0" | ||
450 | sodipodi:nodetypes="ccccc" /> | ||
451 | <path | ||
452 | sodipodi:nodetypes="ccccc" | ||
453 | inkscape:connector-curvature="0" | ||
454 | id="path3404" | ||
455 | d="m 599.82047,678.2289 34.30741,-25.94116 0,26.5407 -34.30741,34.25912 z" | ||
456 | style="fill:#c87137;fill-opacity:1;stroke:#faf6a2;stroke-width:0.51140249;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
457 | inkscape:transform-center-x="-70.147578" | ||
458 | inkscape:transform-center-y="15.429055" /> | ||
459 | <path | ||
460 | sodipodi:nodetypes="ccccc" | ||
461 | inkscape:connector-curvature="0" | ||
462 | id="path3406" | ||
463 | d="m 600.04863,707.77865 33.90941,-29.55535 0.89049,128.35487 -34.7999,26.01123 z" | ||
464 | style="fill:#37c837;fill-opacity:1;stroke:#faf6a2;stroke-width:1.19094384;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
465 | <path | ||
466 | inkscape:connector-curvature="0" | ||
467 | id="path3410" | ||
468 | d="m 356.56358,554.09281 120.92249,0 0,124.19268 -120.92249,0 z" | ||
469 | style="fill:#ffeeaa;fill-opacity:1;stroke:#faf6a2;stroke-width:0.91608089;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
470 | <path | ||
471 | style="fill:#ffeeaa;fill-opacity:1;stroke:#faf6a2;stroke-width:1.11023378;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
472 | d="m 177.52518,554.09281 177.51841,0 0,124.25702 -177.51841,0 z" | ||
473 | id="path3412" | ||
474 | inkscape:connector-curvature="0" /> | ||
475 | <rect | ||
476 | style="fill:#c87137;fill-opacity:1;stroke:#c48069;stroke-width:1.11264122;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
477 | id="rect6557-7" | ||
478 | width="177.44882" | ||
479 | height="30.529778" | ||
480 | x="177.65657" | ||
481 | y="523.95343" /> | ||
482 | <rect | ||
483 | y="678.1521" | ||
484 | x="116.73995" | ||
485 | height="29.53463" | ||
486 | width="177.54182" | ||
487 | id="rect3408" | ||
488 | style="fill:#c87137;fill-opacity:1;stroke:#c48069;stroke-width:1.09464383;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
489 | <rect | ||
490 | y="523.95343" | ||
491 | x="356.55023" | ||
492 | height="30.529778" | ||
493 | width="120.86897" | ||
494 | id="rect3420" | ||
495 | style="fill:#c87137;fill-opacity:1;stroke:#c48069;stroke-width:0.91828173;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
496 | <rect | ||
497 | style="fill:#c87137;fill-opacity:1;stroke:#c48069;stroke-width:0.91828173;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
498 | id="rect3422" | ||
499 | width="120.86897" | ||
500 | height="30.529778" | ||
501 | x="478.54919" | ||
502 | y="523.95343" /> | ||
503 | <text | ||
504 | xml:space="preserve" | ||
505 | style="font-size:22.32217598px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
506 | x="372.34232" | ||
507 | y="622.53217" | ||
508 | id="text6656-2" | ||
509 | sodipodi:linespacing="125%" | ||
510 | transform="scale(1.0052948,0.9947331)"><tspan | ||
511 | sodipodi:role="line" | ||
512 | id="tspan6658-2" | ||
513 | x="372.34232" | ||
514 | y="622.53217">Service</tspan></text> | ||
515 | <text | ||
516 | sodipodi:linespacing="125%" | ||
517 | id="text3424" | ||
518 | y="622.53217" | ||
519 | x="220.56013" | ||
520 | style="font-size:22.32217598px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
521 | xml:space="preserve" | ||
522 | transform="scale(1.0052948,0.9947331)"><tspan | ||
523 | y="622.53217" | ||
524 | x="220.56013" | ||
525 | id="tspan3426" | ||
526 | sodipodi:role="line">Service</tspan></text> | ||
527 | <text | ||
528 | xml:space="preserve" | ||
529 | style="font-size:22.32217598px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
530 | x="493.85532" | ||
531 | y="622.54492" | ||
532 | id="text3428" | ||
533 | sodipodi:linespacing="125%" | ||
534 | transform="scale(1.0052948,0.9947331)"><tspan | ||
535 | sodipodi:role="line" | ||
536 | id="tspan3430" | ||
537 | x="493.85532" | ||
538 | y="622.54492">Service</tspan></text> | ||
539 | <g | ||
540 | id="g3434" | ||
541 | transform="matrix(0.62334353,0,0,0.61679464,120.10238,566.60858)"> | ||
542 | <rect | ||
543 | y="119.99139" | ||
544 | x="198.49498" | ||
545 | height="60.609154" | ||
546 | width="66.670067" | ||
547 | id="rect3436" | ||
548 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
549 | <text | ||
550 | sodipodi:linespacing="125%" | ||
551 | id="text3438" | ||
552 | y="160.39748" | ||
553 | x="206.07112" | ||
554 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
555 | xml:space="preserve"><tspan | ||
556 | y="160.39748" | ||
557 | x="206.07112" | ||
558 | id="tspan3440" | ||
559 | sodipodi:role="line">API</tspan></text> | ||
560 | </g> | ||
561 | <g | ||
562 | transform="matrix(0.62334353,0,0,0.61679464,181.54625,566.60858)" | ||
563 | id="g3442"> | ||
564 | <rect | ||
565 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
566 | id="rect3444" | ||
567 | width="66.670067" | ||
568 | height="60.609154" | ||
569 | x="198.49498" | ||
570 | y="119.99139" /> | ||
571 | <text | ||
572 | xml:space="preserve" | ||
573 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
574 | x="206.07112" | ||
575 | y="160.39748" | ||
576 | id="text3446" | ||
577 | sodipodi:linespacing="125%"><tspan | ||
578 | sodipodi:role="line" | ||
579 | id="tspan3448" | ||
580 | x="206.07112" | ||
581 | y="160.39748">API</tspan></text> | ||
582 | </g> | ||
583 | <g | ||
584 | id="g3450" | ||
585 | transform="matrix(0.62334353,0,0,0.61679464,242.09962,566.60858)"> | ||
586 | <rect | ||
587 | y="119.99139" | ||
588 | x="198.49498" | ||
589 | height="60.609154" | ||
590 | width="66.670067" | ||
591 | id="rect3452" | ||
592 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
593 | <text | ||
594 | sodipodi:linespacing="125%" | ||
595 | id="text3454" | ||
596 | y="160.39748" | ||
597 | x="206.07112" | ||
598 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
599 | xml:space="preserve"><tspan | ||
600 | y="160.39748" | ||
601 | x="206.07112" | ||
602 | id="tspan3456" | ||
603 | sodipodi:role="line">API</tspan></text> | ||
604 | </g> | ||
605 | <g | ||
606 | transform="matrix(0.62334353,0,0,0.61679464,303.54348,566.60858)" | ||
607 | id="g3458"> | ||
608 | <rect | ||
609 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
610 | id="rect3460" | ||
611 | width="66.670067" | ||
612 | height="60.609154" | ||
613 | x="198.49498" | ||
614 | y="119.99139" /> | ||
615 | <text | ||
616 | xml:space="preserve" | ||
617 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
618 | x="206.07112" | ||
619 | y="160.39748" | ||
620 | id="text3462" | ||
621 | sodipodi:linespacing="125%"><tspan | ||
622 | sodipodi:role="line" | ||
623 | id="tspan3464" | ||
624 | x="206.07112" | ||
625 | y="160.39748">API</tspan></text> | ||
626 | </g> | ||
627 | <g | ||
628 | id="g3466" | ||
629 | transform="matrix(0.62334353,0,0,0.61679464,362.76112,566.60858)"> | ||
630 | <rect | ||
631 | y="119.99139" | ||
632 | x="198.49498" | ||
633 | height="60.609154" | ||
634 | width="66.670067" | ||
635 | id="rect3468" | ||
636 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
637 | <text | ||
638 | sodipodi:linespacing="125%" | ||
639 | id="text3470" | ||
640 | y="160.39748" | ||
641 | x="206.07112" | ||
642 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
643 | xml:space="preserve"><tspan | ||
644 | y="160.39748" | ||
645 | x="206.07112" | ||
646 | id="tspan3472" | ||
647 | sodipodi:role="line">API</tspan></text> | ||
648 | </g> | ||
649 | <path | ||
650 | style="fill:#5fd35f;fill-opacity:1;stroke:#faf6a2;stroke-width:1.11993289;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
651 | d="m 420.2626,707.53388 180.11119,0 0,124.61741 -180.11119,0 z" | ||
652 | id="path3490" | ||
653 | inkscape:connector-curvature="0" /> | ||
654 | <g | ||
655 | transform="matrix(0.62334353,0,0,0.61679464,62.665728,566.60858)" | ||
656 | id="g3492"> | ||
657 | <rect | ||
658 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
659 | id="rect3494" | ||
660 | width="66.670067" | ||
661 | height="60.609154" | ||
662 | x="198.49498" | ||
663 | y="119.99139" /> | ||
664 | <text | ||
665 | xml:space="preserve" | ||
666 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
667 | x="206.07112" | ||
668 | y="160.39748" | ||
669 | id="text3496" | ||
670 | sodipodi:linespacing="125%"><tspan | ||
671 | sodipodi:role="line" | ||
672 | id="tspan3498" | ||
673 | x="206.07112" | ||
674 | y="160.39748">API</tspan></text> | ||
675 | </g> | ||
676 | <path | ||
677 | inkscape:connector-curvature="0" | ||
678 | id="path3500" | ||
679 | d="m 116.52597,707.54132 177.63643,0 0,124.61741 -177.63643,0 z" | ||
680 | style="fill:#5fd35f;fill-opacity:1;stroke:#faf6a2;stroke-width:1.11221218;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
681 | <path | ||
682 | style="fill:#5fd35f;fill-opacity:1;stroke:#faf6a2;stroke-width:0.92545629;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
683 | d="m 295.65636,707.63061 122.98965,0 0,124.61741 -122.98965,0 z" | ||
684 | id="path3502" | ||
685 | inkscape:connector-curvature="0" /> | ||
686 | <text | ||
687 | xml:space="preserve" | ||
688 | style="font-size:22.32217598px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
689 | x="162.54019" | ||
690 | y="779.76184" | ||
691 | id="text3508" | ||
692 | sodipodi:linespacing="125%" | ||
693 | transform="scale(1.0052948,0.9947331)"><tspan | ||
694 | sodipodi:role="line" | ||
695 | id="tspan3510" | ||
696 | x="162.54019" | ||
697 | y="779.76184">Service</tspan></text> | ||
698 | <text | ||
699 | sodipodi:linespacing="125%" | ||
700 | id="text3512" | ||
701 | y="779.7619" | ||
702 | x="313.56918" | ||
703 | style="font-size:22.32217598px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
704 | xml:space="preserve" | ||
705 | transform="scale(1.0052948,0.9947331)"><tspan | ||
706 | y="779.7619" | ||
707 | x="313.56918" | ||
708 | id="tspan3514" | ||
709 | sodipodi:role="line">Service</tspan></text> | ||
710 | <text | ||
711 | xml:space="preserve" | ||
712 | style="font-size:22.32217598px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
713 | x="465.48401" | ||
714 | y="779.7619" | ||
715 | id="text3516" | ||
716 | sodipodi:linespacing="125%" | ||
717 | transform="scale(1.0052948,0.9947331)"><tspan | ||
718 | sodipodi:role="line" | ||
719 | id="tspan3518" | ||
720 | x="465.48401" | ||
721 | y="779.7619">Service</tspan></text> | ||
722 | <rect | ||
723 | style="fill:#c87137;fill-opacity:1;stroke:#c48069;stroke-width:0.91063529;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
724 | id="rect3520" | ||
725 | width="122.86946" | ||
726 | height="29.53463" | ||
727 | x="295.75125" | ||
728 | y="678.1521" /> | ||
729 | <rect | ||
730 | y="678.1521" | ||
731 | x="420.27423" | ||
732 | height="29.53463" | ||
733 | width="179.80205" | ||
734 | id="rect3522" | ||
735 | style="fill:#c87137;fill-opacity:1;stroke:#c48069;stroke-width:1.10158956;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
736 | </g> | ||
737 | </svg> | ||
diff --git a/doc/documentation/images/service_lego_block.png b/doc/documentation/images/service_lego_block.png new file mode 100644 index 000000000..56caf6b9c --- /dev/null +++ b/doc/documentation/images/service_lego_block.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/service_lego_block.svg b/doc/documentation/images/service_lego_block.svg new file mode 100644 index 000000000..ef0d0234f --- /dev/null +++ b/doc/documentation/images/service_lego_block.svg | |||
@@ -0,0 +1,345 @@ | |||
1 | <?xml version="1.0" encoding="UTF-8" standalone="no"?> | ||
2 | <!-- Created with Inkscape (http://www.inkscape.org/) --> | ||
3 | |||
4 | <svg | ||
5 | xmlns:osb="http://www.openswatchbook.org/uri/2009/osb" | ||
6 | xmlns:dc="http://purl.org/dc/elements/1.1/" | ||
7 | xmlns:cc="http://creativecommons.org/ns#" | ||
8 | xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" | ||
9 | xmlns:svg="http://www.w3.org/2000/svg" | ||
10 | xmlns="http://www.w3.org/2000/svg" | ||
11 | xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd" | ||
12 | xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape" | ||
13 | width="744.09448819" | ||
14 | height="1052.3622047" | ||
15 | id="svg2" | ||
16 | version="1.1" | ||
17 | inkscape:version="0.48.2 r9819" | ||
18 | sodipodi:docname="Lego block 3.svg"> | ||
19 | <defs | ||
20 | id="defs4"> | ||
21 | <linearGradient | ||
22 | id="linearGradient6602"> | ||
23 | <stop | ||
24 | style="stop-color:#df8060;stop-opacity:1;" | ||
25 | offset="0" | ||
26 | id="stop6604" /> | ||
27 | <stop | ||
28 | style="stop-color:#df8002;stop-opacity:0;" | ||
29 | offset="1" | ||
30 | id="stop6606" /> | ||
31 | </linearGradient> | ||
32 | <linearGradient | ||
33 | id="linearGradient4392" | ||
34 | osb:paint="solid"> | ||
35 | <stop | ||
36 | style="stop-color:#faf6a6;stop-opacity:1;" | ||
37 | offset="0" | ||
38 | id="stop4394" /> | ||
39 | </linearGradient> | ||
40 | <inkscape:perspective | ||
41 | sodipodi:type="inkscape:persp3d" | ||
42 | inkscape:vp_x="883.99395 : 559.99673 : 1" | ||
43 | inkscape:vp_y="13.319386 : 993.87659 : 0" | ||
44 | inkscape:vp_z="285.3157 : 504.79962 : 1" | ||
45 | inkscape:persp3d-origin="481.39556 : 281.96355 : 1" | ||
46 | id="perspective3070" /> | ||
47 | <inkscape:perspective | ||
48 | sodipodi:type="inkscape:persp3d" | ||
49 | inkscape:vp_x="76.097926 : 349.87282 : 1" | ||
50 | inkscape:vp_y="-13.319386 : 979.366 : 0" | ||
51 | inkscape:vp_z="752.55793 : 376.31441 : 1" | ||
52 | inkscape:persp3d-origin="373.64045 : 350.98006 : 1" | ||
53 | id="perspective3012" /> | ||
54 | </defs> | ||
55 | <sodipodi:namedview | ||
56 | id="base" | ||
57 | pagecolor="#ffffff" | ||
58 | bordercolor="#666666" | ||
59 | borderopacity="1.0" | ||
60 | inkscape:pageopacity="0.0" | ||
61 | inkscape:pageshadow="2" | ||
62 | inkscape:zoom="0.49497475" | ||
63 | inkscape:cx="385.59974" | ||
64 | inkscape:cy="826.03166" | ||
65 | inkscape:document-units="px" | ||
66 | inkscape:current-layer="layer1" | ||
67 | showgrid="false" | ||
68 | inkscape:window-width="1366" | ||
69 | inkscape:window-height="721" | ||
70 | inkscape:window-x="-2" | ||
71 | inkscape:window-y="-3" | ||
72 | inkscape:window-maximized="1" /> | ||
73 | <metadata | ||
74 | id="metadata7"> | ||
75 | <rdf:RDF> | ||
76 | <cc:Work | ||
77 | rdf:about=""> | ||
78 | <dc:format>image/svg+xml</dc:format> | ||
79 | <dc:type | ||
80 | rdf:resource="http://purl.org/dc/dcmitype/StillImage" /> | ||
81 | <dc:title></dc:title> | ||
82 | </cc:Work> | ||
83 | </rdf:RDF> | ||
84 | </metadata> | ||
85 | <g | ||
86 | inkscape:label="Layer 1" | ||
87 | inkscape:groupmode="layer" | ||
88 | id="layer1"> | ||
89 | <path | ||
90 | style="fill:#ffdd55;fill-opacity:1;stroke:#faf6a2;stroke-width:2.26315212;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
91 | d="m 74.934278,230.09308 453.654042,0 0,202.04036 -453.654042,0 z" | ||
92 | id="rect5973" | ||
93 | inkscape:connector-curvature="0" /> | ||
94 | <path | ||
95 | style="fill:#ffcc00;fill-opacity:1;stroke:#faf6a2;stroke-width:1.92068994;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
96 | d="m 528.67583,229.34787 55.11351,-29.34622 0,190.24271 -55.11351,41.45733 z" | ||
97 | id="rect6542" | ||
98 | inkscape:connector-curvature="0" | ||
99 | sodipodi:nodetypes="ccccc" /> | ||
100 | <rect | ||
101 | style="fill:#d38d5f;fill-opacity:1;stroke:#c48069;stroke-width:2.2674458;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
102 | id="rect6557" | ||
103 | width="454.54535" | ||
104 | height="49.497475" | ||
105 | x="74.764442" | ||
106 | y="180.60052" /> | ||
107 | <path | ||
108 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:0.8206054;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
109 | d="m 528.30981,180.60052 55.47954,-27.27412 0,46.46702 -55.47954,29.29442 z" | ||
110 | id="rect6561" | ||
111 | inkscape:connector-curvature="0" | ||
112 | sodipodi:nodetypes="ccccc" /> | ||
113 | <path | ||
114 | sodipodi:nodetypes="ccccc" | ||
115 | inkscape:connector-curvature="0" | ||
116 | id="path6564" | ||
117 | d="m 528.30981,180.72501 55.03773,-27.7723 0,47.31578 -55.03773,29.8295 z" | ||
118 | style="fill:#d38d5f;fill-opacity:1;stroke:#faf6a2;stroke-width:0.82476228;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
119 | inkscape:transform-center-x="-70.147578" | ||
120 | inkscape:transform-center-y="15.429055" /> | ||
121 | <path | ||
122 | style="fill:#deaa87;fill-opacity:1;stroke:#faf6a2;stroke-width:2.23265362;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
123 | d="m 153.39374,154.33657 430.4643,-1.01015 -54.4837,27.27411 -453.213248,0 z" | ||
124 | id="rect6568" | ||
125 | inkscape:connector-curvature="0" | ||
126 | sodipodi:nodetypes="ccccc" /> | ||
127 | <text | ||
128 | xml:space="preserve" | ||
129 | style="font-size:40px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
130 | x="352.03815" | ||
131 | y="-190.12544" | ||
132 | id="text6623" | ||
133 | sodipodi:linespacing="125%"><tspan | ||
134 | sodipodi:role="line" | ||
135 | id="tspan6625" | ||
136 | x="352.03815" | ||
137 | y="-190.12544" /></text> | ||
138 | <text | ||
139 | xml:space="preserve" | ||
140 | style="font-size:40px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
141 | x="338.40109" | ||
142 | y="-300.73715" | ||
143 | id="text6627" | ||
144 | sodipodi:linespacing="125%"><tspan | ||
145 | sodipodi:role="line" | ||
146 | id="tspan6629" | ||
147 | x="338.40109" | ||
148 | y="-300.73715" /></text> | ||
149 | <rect | ||
150 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
151 | id="rect6571" | ||
152 | width="66.670067" | ||
153 | height="60.609154" | ||
154 | x="198.49498" | ||
155 | y="119.99139" /> | ||
156 | <path | ||
157 | style="fill:#ff6600;fill-opacity:1;stroke:#faf6a2;stroke-width:1.98413372;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
158 | d="m 265.16503,119.45792 44.95179,-22.465406 0,57.057986 -44.95179,26.55003 z" | ||
159 | id="path6600" | ||
160 | inkscape:connector-curvature="0" | ||
161 | sodipodi:nodetypes="ccccc" /> | ||
162 | <path | ||
163 | style="fill:#ff6600;fill-opacity:1;stroke:#c48069;stroke-width:1.99687159;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
164 | d="m 243.06977,97.26295 66.86223,10e-7 -45.08135,22.728439 -66.3557,0 z" | ||
165 | id="path6617" | ||
166 | inkscape:connector-curvature="0" | ||
167 | sodipodi:nodetypes="ccccc" /> | ||
168 | <text | ||
169 | xml:space="preserve" | ||
170 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
171 | x="206.07112" | ||
172 | y="160.39748" | ||
173 | id="text6631" | ||
174 | sodipodi:linespacing="125%"><tspan | ||
175 | sodipodi:role="line" | ||
176 | id="tspan6633" | ||
177 | x="206.07112" | ||
178 | y="160.39748">API</tspan></text> | ||
179 | <rect | ||
180 | y="119.99139" | ||
181 | x="313.65237" | ||
182 | height="60.609154" | ||
183 | width="66.670067" | ||
184 | id="rect6573" | ||
185 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
186 | <path | ||
187 | sodipodi:nodetypes="ccccc" | ||
188 | inkscape:connector-curvature="0" | ||
189 | id="path6598" | ||
190 | d="m 379.81735,119.56755 44.95179,-22.425126 0,56.955676 -44.95179,26.50243 z" | ||
191 | style="fill:#ff6600;fill-opacity:1;stroke:#faf6a2;stroke-width:1.98235416;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
192 | <path | ||
193 | sodipodi:nodetypes="ccccc" | ||
194 | inkscape:connector-curvature="0" | ||
195 | id="path6615" | ||
196 | d="m 358.25117,97.26295 66.89824,10e-7 -45.10563,22.728439 -66.39143,0 z" | ||
197 | style="fill:#ff6600;fill-opacity:1;stroke:#c48069;stroke-width:1.99740911;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
198 | <text | ||
199 | sodipodi:linespacing="125%" | ||
200 | id="text6635" | ||
201 | y="160.39748" | ||
202 | x="322.23865" | ||
203 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
204 | xml:space="preserve"><tspan | ||
205 | y="160.39748" | ||
206 | x="322.23865" | ||
207 | id="tspan6637" | ||
208 | sodipodi:role="line">API</tspan></text> | ||
209 | <rect | ||
210 | style="fill:#ff9955;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
211 | id="rect6575" | ||
212 | width="66.670067" | ||
213 | height="60.609154" | ||
214 | x="428.80978" | ||
215 | y="119.99139" /> | ||
216 | <path | ||
217 | style="fill:#ff6600;fill-opacity:1;stroke:#faf6a2;stroke-width:1.98960423;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
218 | d="m 494.97474,119.62537 44.95179,-22.589454 0,57.373054 -44.95179,26.69664 z" | ||
219 | id="rect6595" | ||
220 | inkscape:connector-curvature="0" | ||
221 | sodipodi:nodetypes="ccccc" /> | ||
222 | <path | ||
223 | style="fill:#ff6600;fill-opacity:1;stroke:#c48069;stroke-width:1.99399996;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
224 | d="m 473.25645,97.26295 66.67007,10e-7 -44.95179,22.728439 -66.16499,0 z" | ||
225 | id="rect6612" | ||
226 | inkscape:connector-curvature="0" | ||
227 | sodipodi:nodetypes="ccccc" /> | ||
228 | <text | ||
229 | xml:space="preserve" | ||
230 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
231 | x="439.41635" | ||
232 | y="159.89241" | ||
233 | id="text6639" | ||
234 | sodipodi:linespacing="125%"><tspan | ||
235 | sodipodi:role="line" | ||
236 | id="tspan6641" | ||
237 | x="439.41635" | ||
238 | y="159.89241">API</tspan></text> | ||
239 | <g | ||
240 | style="font-size:24px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
241 | id="text6643" /> | ||
242 | <text | ||
243 | xml:space="preserve" | ||
244 | style="font-size:24px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
245 | x="71.720833" | ||
246 | y="95.747719" | ||
247 | id="text6648" | ||
248 | sodipodi:linespacing="125%"><tspan | ||
249 | sodipodi:role="line" | ||
250 | id="tspan6650" | ||
251 | x="71.720833" | ||
252 | y="95.747719" /></text> | ||
253 | <text | ||
254 | xml:space="preserve" | ||
255 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
256 | x="176.77669" | ||
257 | y="216.96603" | ||
258 | id="text6652" | ||
259 | sodipodi:linespacing="125%"><tspan | ||
260 | sodipodi:role="line" | ||
261 | id="tspan6654" | ||
262 | x="176.77669" | ||
263 | y="216.96603">Network Protocol</tspan></text> | ||
264 | <text | ||
265 | xml:space="preserve" | ||
266 | style="font-size:36px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
267 | x="233.34526" | ||
268 | y="312.93051" | ||
269 | id="text6656" | ||
270 | sodipodi:linespacing="125%"><tspan | ||
271 | sodipodi:role="line" | ||
272 | id="tspan6658" | ||
273 | x="233.34526" | ||
274 | y="312.93051">Service</tspan></text> | ||
275 | <rect | ||
276 | style="fill:#ffffff;fill-opacity:1;stroke:#faf6a2;stroke-width:2.09665918;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
277 | id="rect6660" | ||
278 | width="66.670067" | ||
279 | height="66.609154" | ||
280 | x="216.67773" | ||
281 | y="371.51938" /> | ||
282 | <rect | ||
283 | y="371.51938" | ||
284 | x="322.74374" | ||
285 | height="64.373825" | ||
286 | width="66.670067" | ||
287 | id="rect6662" | ||
288 | style="fill:#ffffff;fill-opacity:1;stroke:#faf6a2;stroke-width:2.06117821;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
289 | <rect | ||
290 | style="fill:#ffffff;fill-opacity:1;stroke:#faf6a2;stroke-width:2;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" | ||
291 | id="rect6664" | ||
292 | width="66.670067" | ||
293 | height="60.609154" | ||
294 | x="423.75903" | ||
295 | y="372.52951" /> | ||
296 | <path | ||
297 | sodipodi:nodetypes="ccccc" | ||
298 | inkscape:connector-curvature="0" | ||
299 | id="path6666" | ||
300 | d="m 423.61996,372.56359 67.23534,-0.62641 0,19.59587 -68.24549,41.17879 z" | ||
301 | style="fill:#ffcc00;fill-opacity:1;stroke:#faf6a2;stroke-width:0.98368376;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
302 | <path | ||
303 | style="fill:#ffcc00;fill-opacity:1;stroke:#faf6a2;stroke-width:0.98368376;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
304 | d="m 322.60471,371.55344 67.23534,0.38374 0,23.63648 -67.23534,37.13818 z" | ||
305 | id="path6668" | ||
306 | inkscape:connector-curvature="0" | ||
307 | sodipodi:nodetypes="ccccc" /> | ||
308 | <path | ||
309 | sodipodi:nodetypes="ccccc" | ||
310 | inkscape:connector-curvature="0" | ||
311 | id="path6670" | ||
312 | d="m 322.60471,371.55344 67.23534,0.38374 0,23.63648 -67.23534,37.13818 z" | ||
313 | style="fill:#ffcc00;fill-opacity:1;stroke:#faf6a2;stroke-width:0.98368376;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
314 | <path | ||
315 | style="fill:#ffcc00;fill-opacity:1;stroke:#faf6a2;stroke-width:0.98368376;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" | ||
316 | d="m 216.53869,371.55344 67.23534,0.38374 0,23.63648 -67.23534,37.13818 z" | ||
317 | id="path6672" | ||
318 | inkscape:connector-curvature="0" | ||
319 | sodipodi:nodetypes="ccccc" /> | ||
320 | <text | ||
321 | xml:space="preserve" | ||
322 | style="font-size:32px;font-style:normal;font-weight:normal;line-height:125%;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;font-family:Sans" | ||
323 | x="262.63965" | ||
324 | y="666.48389" | ||
325 | id="text6711" | ||
326 | sodipodi:linespacing="125%"><tspan | ||
327 | sodipodi:role="line" | ||
328 | id="tspan6713" | ||
329 | x="262.63965" | ||
330 | y="666.48389" /></text> | ||
331 | <rect | ||
332 | y="371.51938" | ||
333 | x="111.62187" | ||
334 | height="70.798637" | ||
335 | width="66.670067" | ||
336 | id="rect6721" | ||
337 | style="fill:#ffffff;fill-opacity:1;stroke:#faf6a2;stroke-width:2.1615901;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dasharray:none;stroke-dashoffset:0" /> | ||
338 | <path | ||
339 | sodipodi:nodetypes="ccccc" | ||
340 | inkscape:connector-curvature="0" | ||
341 | id="path6723" | ||
342 | d="m 111.48283,370.54329 67.23534,0.38374 0,23.63648 -67.23534,37.13818 z" | ||
343 | style="fill:#ffcc00;fill-opacity:1;stroke:#faf6a2;stroke-width:0.98368376;stroke-linejoin:bevel;stroke-miterlimit:4;stroke-opacity:0;stroke-dashoffset:0" /> | ||
344 | </g> | ||
345 | </svg> | ||
diff --git a/doc/documentation/images/service_stack.png b/doc/documentation/images/service_stack.png new file mode 100644 index 000000000..747d087b2 --- /dev/null +++ b/doc/documentation/images/service_stack.png | |||
Binary files differ | |||
diff --git a/doc/documentation/images/structure.dot b/doc/documentation/images/structure.dot new file mode 100644 index 000000000..a53db90b8 --- /dev/null +++ b/doc/documentation/images/structure.dot | |||
@@ -0,0 +1,124 @@ | |||
1 | // house = application | ||
2 | // circle (default) = service | ||
3 | // box = daemon | ||
4 | // diamond = library | ||
5 | // black line = dependency | ||
6 | // blue line = extension via plugin | ||
7 | // red line = possibly useful | ||
8 | // dashed = in planning | ||
9 | |||
10 | // this is what we have...o | ||
11 | digraph dependencies { | ||
12 | splines = true; | ||
13 | |||
14 | voting [shape=house]; | ||
15 | voting -> consensus; | ||
16 | voting -> identity; | ||
17 | voting -> cadet; | ||
18 | voting -> secretsharing; | ||
19 | secretsharing -> consensus; | ||
20 | |||
21 | fs [shape=house]; | ||
22 | fs -> dht; | ||
23 | fs -> core; | ||
24 | fs -> datastore; | ||
25 | fs -> cadet; | ||
26 | fs -> ats; | ||
27 | fs -> block [style=dotted,color=blue]; | ||
28 | fs -> identity; | ||
29 | exit [shape=box]; | ||
30 | exit -> cadet; | ||
31 | exit -> tun; | ||
32 | exit -> dnsstub; | ||
33 | vpn -> cadet; | ||
34 | vpn -> regex; | ||
35 | vpn -> tun; | ||
36 | pt [shape=house]; | ||
37 | pt -> cadet; | ||
38 | pt -> vpn; | ||
39 | pt -> dns; | ||
40 | pt -> dnsparser; | ||
41 | dns -> tun; | ||
42 | dns -> dnsstub; | ||
43 | zonemaster [shape=house]; | ||
44 | zonemaster -> namestore; | ||
45 | zonemaster -> dht; | ||
46 | gns -> dns; | ||
47 | gns -> dht; | ||
48 | gns -> block [style=dotted,color=blue]; | ||
49 | gns -> revocation; | ||
50 | gns -> vpn; | ||
51 | gns -> dnsparser; | ||
52 | gns -> dnsstub; | ||
53 | gns -> identity; | ||
54 | revocation -> core; | ||
55 | revocation -> set; | ||
56 | namestore -> identity; | ||
57 | namestore -> gnsrecord; | ||
58 | dnsparser -> gnsrecord [style=dotted,color=blue]; | ||
59 | conversation -> gnsrecord [style=dotted,color=blue]; | ||
60 | gns -> gnsrecord; | ||
61 | dht -> core; | ||
62 | dht -> nse; | ||
63 | dht -> block; | ||
64 | dht -> datacache; | ||
65 | dht -> peerinfo; | ||
66 | dht -> hello; | ||
67 | nse -> core; | ||
68 | regex -> block [style=dotted,color=blue]; | ||
69 | block [shape=diamond]; | ||
70 | datacache [shape=diamond]; | ||
71 | cadet -> core [weight=2]; | ||
72 | cadet -> dht; | ||
73 | cadet -> block [style=dotted,color=blue]; | ||
74 | conversation [shape=house]; | ||
75 | conversation -> cadet; | ||
76 | conversation -> gns; | ||
77 | conversation -> speaker; | ||
78 | conversation -> microphone; | ||
79 | speaker [shape=diamond]; | ||
80 | microphone [shape=diamond]; | ||
81 | regex -> dht; | ||
82 | core -> transport; | ||
83 | topology [shape=box]; | ||
84 | topology -> peerinfo; | ||
85 | topology -> transport; | ||
86 | topology -> core; | ||
87 | topology -> hello; | ||
88 | hostlist [shape=box]; | ||
89 | hostlist -> core; | ||
90 | hostlist -> peerinfo; | ||
91 | hostlist -> hello; | ||
92 | transport -> ats; | ||
93 | transport -> hello; | ||
94 | transport -> peerinfo; | ||
95 | transport -> nat; | ||
96 | transport -> fragmentation; | ||
97 | consensus -> set; | ||
98 | consensus -> cadet; | ||
99 | scalarproduct -> set; | ||
100 | scalarproduct -> cadet; | ||
101 | set -> cadet; | ||
102 | peerinfo -> hello; | ||
103 | fragmentation [shape=diamond]; | ||
104 | hello [shape=diamond]; | ||
105 | nat [shape=diamond]; | ||
106 | tun [shape=diamond]; | ||
107 | dnsparser [shape=diamond]; | ||
108 | dnsstub [shape=diamond]; | ||
109 | |||
110 | secushare [shape=house]; | ||
111 | multicast; | ||
112 | psyc; | ||
113 | social -> psyc; | ||
114 | social -> gns; | ||
115 | psyc -> psycstore; | ||
116 | psycstore; | ||
117 | social; | ||
118 | secushare -> social; | ||
119 | psyc -> multicast; | ||
120 | multicast -> cadet; | ||
121 | |||
122 | rps; | ||
123 | rps -> core; | ||
124 | } | ||
diff --git a/doc/documentation/index.html b/doc/documentation/index.html new file mode 100644 index 000000000..0c3b04e9d --- /dev/null +++ b/doc/documentation/index.html | |||
@@ -0,0 +1,35 @@ | |||
1 | <title>GNUnet - GNUnet Manuals and Handbooks</title> | ||
2 | <h2>GNUnet - GNUnet Manuals and Handbooks</h2> | ||
3 | |||
4 | <address>GNUnet e.V.</address> | ||
5 | <address>Fakultät für Informatik -- I8</address> | ||
6 | <address>Technische Universität München</address> | ||
7 | <address>Boltzmannstraße 3</address> | ||
8 | <address>85748 Garching</address> | ||
9 | <address>GERMANY</address> | ||
10 | |||
11 | <p>The following handbooks and manuals are available:</p> | ||
12 | |||
13 | <ul> | ||
14 | <li><a href="gnunet/index.html">GNUnet Reference Manual</li> | ||
15 | <li><a href="gnunet-c-tutorial/index.html">GNUnet C Tutorial</li> | ||
16 | </ul> | ||
17 | |||
18 | <div id="footer"> | ||
19 | <div class="unprintable"> | ||
20 | |||
21 | <p>Please send general FSF & GNU inquiries to | ||
22 | <a href="mailto:gnu@gnu.org"><gnu@gnu.org></a>. | ||
23 | There are also <a href="/contact/">other ways to contact</a> | ||
24 | the FSF. Broken links and other corrections or suggestions can be sent | ||
25 | to <a href="mailto:gnunet-developers@gnu.org"><gnunet-developers@gnu.org></a>.</p> | ||
26 | </div> | ||
27 | |||
28 | <p>Copyright © 2001 - 2017 GNUnet e.V.</p> | ||
29 | |||
30 | <p>This page is licensed under a FIXME License.</p> | ||
31 | |||
32 | </div> | ||
33 | </div> | ||
34 | </body> | ||
35 | </html> | ||
diff --git a/doc/documentation/run-gendocs.sh b/doc/documentation/run-gendocs.sh new file mode 100755 index 000000000..d02570177 --- /dev/null +++ b/doc/documentation/run-gendocs.sh | |||
@@ -0,0 +1,18 @@ | |||
1 | #!/bin/sh | ||
2 | |||
3 | make version.texi | ||
4 | make version2.texi | ||
5 | ./gendocs.sh --email gnunet-developers@gnu.org gnunet-c-tutorial "GNUnet C Tutorial" -o "manual/gnunet-c-tutorial" | ||
6 | #cd manual | ||
7 | #mkdir gnunet-c-tutorial | ||
8 | #mv * gnunet-c-tutorial/ | ||
9 | #cd .. | ||
10 | ./gendocs.sh --email gnunet-developers@gnu.org gnunet "GNUnet Reference Manual" -o "manual/gnunet" | ||
11 | #cd manual | ||
12 | #mkdir handbook | ||
13 | #mkdir ../tmp-gnunet | ||
14 | #mv gnunet ../tmp-gnunet | ||
15 | #mv * handbook/ | ||
16 | #mv ../tmp-gnunet gnunet | ||
17 | cp "index.html" manual/ | ||
18 | printf "Success" | ||
diff --git a/doc/documentation/testbed_test.c b/doc/documentation/testbed_test.c new file mode 100644 index 000000000..1696234b0 --- /dev/null +++ b/doc/documentation/testbed_test.c | |||
@@ -0,0 +1,99 @@ | |||
1 | #include <unistd.h> | ||
2 | #include <gnunet/platform.h> | ||
3 | #include <gnunet/gnunet_util_lib.h> | ||
4 | #include <gnunet/gnunet_testbed_service.h> | ||
5 | #include <gnunet/gnunet_dht_service.h> | ||
6 | |||
7 | #define NUM_PEERS 20 | ||
8 | |||
9 | static struct GNUNET_TESTBED_Operation *dht_op; | ||
10 | |||
11 | static struct GNUNET_DHT_Handle *dht_handle; | ||
12 | |||
13 | |||
14 | struct MyContext | ||
15 | { | ||
16 | int ht_len; | ||
17 | } ctxt; | ||
18 | |||
19 | |||
20 | static int result; | ||
21 | |||
22 | |||
23 | static void | ||
24 | shutdown_task (void *cls) | ||
25 | { | ||
26 | if (NULL != dht_op) | ||
27 | { | ||
28 | GNUNET_TESTBED_operation_done (dht_op); | ||
29 | dht_op = NULL; | ||
30 | dht_handle = NULL; | ||
31 | } | ||
32 | result = GNUNET_OK; | ||
33 | } | ||
34 | |||
35 | |||
36 | static void | ||
37 | service_connect_comp (void *cls, | ||
38 | struct GNUNET_TESTBED_Operation *op, | ||
39 | void *ca_result, | ||
40 | const char *emsg) | ||
41 | { | ||
42 | GNUNET_assert (op == dht_op); | ||
43 | dht_handle = ca_result; | ||
44 | // Do work here... | ||
45 | GNUNET_SCHEDULER_shutdown (); | ||
46 | } | ||
47 | |||
48 | |||
49 | static void * | ||
50 | dht_ca (void *cls, const struct GNUNET_CONFIGURATION_Handle *cfg) | ||
51 | { | ||
52 | struct MyContext *ctxt = cls; | ||
53 | |||
54 | dht_handle = GNUNET_DHT_connect (cfg, ctxt->ht_len); | ||
55 | return dht_handle; | ||
56 | } | ||
57 | |||
58 | |||
59 | static void | ||
60 | dht_da (void *cls, void *op_result) | ||
61 | { | ||
62 | struct MyContext *ctxt = cls; | ||
63 | |||
64 | GNUNET_DHT_disconnect ((struct GNUNET_DHT_Handle *) op_result); | ||
65 | dht_handle = NULL; | ||
66 | } | ||
67 | |||
68 | |||
69 | static void | ||
70 | test_master (void *cls, | ||
71 | struct GNUNET_TESTBED_RunHandle *h, | ||
72 | unsigned int num_peers, | ||
73 | struct GNUNET_TESTBED_Peer **peers, | ||
74 | unsigned int links_succeeded, | ||
75 | unsigned int links_failed) | ||
76 | { | ||
77 | ctxt.ht_len = 10; | ||
78 | dht_op = GNUNET_TESTBED_service_connect | ||
79 | (NULL, peers[0], "dht", | ||
80 | &service_connect_comp, NULL, | ||
81 | &dht_ca, &dht_da, &ctxt); | ||
82 | GNUNET_SCHEDULER_add_shutdown (&shutdown_task, NULL); | ||
83 | } | ||
84 | |||
85 | |||
86 | int | ||
87 | main (int argc, char **argv) | ||
88 | { | ||
89 | int ret; | ||
90 | |||
91 | result = GNUNET_SYSERR; | ||
92 | ret = GNUNET_TESTBED_test_run | ||
93 | ("awesome-test", "template.conf", | ||
94 | NUM_PEERS, 0LL, | ||
95 | NULL, NULL, &test_master, NULL); | ||
96 | if ( (GNUNET_OK != ret) || (GNUNET_OK != result) ) | ||
97 | return 1; | ||
98 | return 0; | ||
99 | } | ||
diff --git a/doc/documentation/tutorial-examples/001.c b/doc/documentation/tutorial-examples/001.c new file mode 100644 index 000000000..7f6699dd2 --- /dev/null +++ b/doc/documentation/tutorial-examples/001.c | |||
@@ -0,0 +1,29 @@ | |||
1 | #include <gnunet/platform.h> | ||
2 | #include <gnunet/gnunet_util_lib.h> | ||
3 | |||
4 | static int ret; | ||
5 | |||
6 | static void | ||
7 | run (void *cls, | ||
8 | char *const *args, | ||
9 | const char *cfgfile, | ||
10 | const struct GNUNET_CONFIGURATION_Handle *cfg) | ||
11 | { | ||
12 | // main code here | ||
13 | ret = 0; | ||
14 | } | ||
15 | |||
16 | int | ||
17 | main (int argc, char *const *argv) | ||
18 | { | ||
19 | struct GNUNET_GETOPT_CommandLineOption options[] = { | ||
20 | GNUNET_GETOPT_OPTION_END | ||
21 | }; | ||
22 | return (GNUNET_OK == | ||
23 | GNUNET_PROGRAM_run (argc, | ||
24 | argv, | ||
25 | "binary-name", | ||
26 | gettext_noop ("binary description text"), | ||
27 | options, &run, NULL)) ? ret : 1; | ||
28 | } | ||
29 | |||
diff --git a/doc/documentation/tutorial-examples/002.c b/doc/documentation/tutorial-examples/002.c new file mode 100644 index 000000000..02233fd61 --- /dev/null +++ b/doc/documentation/tutorial-examples/002.c | |||
@@ -0,0 +1,17 @@ | |||
1 | static char *string_option; | ||
2 | static int a_flag; | ||
3 | |||
4 | // ... | ||
5 | struct GNUNET_GETOPT_CommandLineOption options[] = { | ||
6 | GNUNET_GETOPT_option_string ('s', "name", "SOMESTRING", | ||
7 | gettext_noop ("text describing the string_option NAME"), | ||
8 | &string_option}, | ||
9 | GNUNET_GETOPT_option_flag ('f', "flag", | ||
10 | gettext_noop ("text describing the flag option"), | ||
11 | &a_flag), | ||
12 | GNUNET_GETOPT_OPTION_END | ||
13 | }; | ||
14 | string_option = NULL; | ||
15 | a_flag = GNUNET_SYSERR; | ||
16 | // ... | ||
17 | |||
diff --git a/doc/documentation/tutorial-examples/003.c b/doc/documentation/tutorial-examples/003.c new file mode 100644 index 000000000..d158d7e75 --- /dev/null +++ b/doc/documentation/tutorial-examples/003.c | |||
@@ -0,0 +1,11 @@ | |||
1 | struct GNUNET_MQ_MessageHandlers handlers[] = { | ||
2 | // ... | ||
3 | GNUNET_MQ_handler_end () | ||
4 | }; | ||
5 | struct GNUNET_MQ_Handle *mq; | ||
6 | |||
7 | mq = GNUNET_CLIENT_connect (cfg, | ||
8 | "service-name", | ||
9 | handlers, | ||
10 | &error_cb, | ||
11 | NULL); | ||
diff --git a/doc/documentation/tutorial-examples/004.c b/doc/documentation/tutorial-examples/004.c new file mode 100644 index 000000000..0ef007907 --- /dev/null +++ b/doc/documentation/tutorial-examples/004.c | |||
@@ -0,0 +1,5 @@ | |||
1 | struct GNUNET_MessageHeader | ||
2 | { | ||
3 | uint16_t size GNUNET_PACKED; | ||
4 | uint16_t type GNUNET_PACKED; | ||
5 | }; | ||
diff --git a/doc/documentation/tutorial-examples/005.c b/doc/documentation/tutorial-examples/005.c new file mode 100644 index 000000000..0c459f509 --- /dev/null +++ b/doc/documentation/tutorial-examples/005.c | |||
@@ -0,0 +1,8 @@ | |||
1 | struct GNUNET_MQ_Envelope *env; | ||
2 | struct GNUNET_MessageHeader *msg; | ||
3 | |||
4 | env = GNUNET_MQ_msg_extra (msg, payload_size, GNUNET_MY_MESSAGE_TYPE); | ||
5 | memcpy (&msg[1], &payload, payload_size); | ||
6 | // Send message via message queue 'mq' | ||
7 | GNUNET_mq_send (mq, env); | ||
8 | |||
diff --git a/doc/documentation/tutorial-examples/006.c b/doc/documentation/tutorial-examples/006.c new file mode 100644 index 000000000..944d2b18c --- /dev/null +++ b/doc/documentation/tutorial-examples/006.c | |||
@@ -0,0 +1,31 @@ | |||
1 | static void | ||
2 | handle_fix (void *cls, const struct MyMessage *msg) | ||
3 | { | ||
4 | // process 'msg' | ||
5 | } | ||
6 | |||
7 | static int | ||
8 | check_var (void *cls, const struct MyVarMessage *msg) | ||
9 | { | ||
10 | // check 'msg' is well-formed | ||
11 | return GNUNET_OK; | ||
12 | } | ||
13 | |||
14 | static void | ||
15 | handle_var (void *cls, const struct MyVarMessage *msg) | ||
16 | { | ||
17 | // process 'msg' | ||
18 | } | ||
19 | |||
20 | struct GNUNET_MQ_MessageHandler handlers[] = { | ||
21 | GNUNET_MQ_hd_fixed_size (fix, | ||
22 | GNUNET_MESSAGE_TYPE_MY_FIX, | ||
23 | struct MyMessage, | ||
24 | NULL), | ||
25 | GNUNET_MQ_hd_fixed_size (var, | ||
26 | GNUNET_MESSAGE_TYPE_MY_VAR, | ||
27 | struct MyVarMessage, | ||
28 | NULL), | ||
29 | |||
30 | GNUNET_MQ_handler_end () | ||
31 | }; | ||
diff --git a/doc/documentation/tutorial-examples/007.c b/doc/documentation/tutorial-examples/007.c new file mode 100644 index 000000000..096539e43 --- /dev/null +++ b/doc/documentation/tutorial-examples/007.c | |||
@@ -0,0 +1,10 @@ | |||
1 | GNUNET_SERVICE_MAIN | ||
2 | ("service-name", | ||
3 | GNUNET_SERVICE_OPTION_NONE, | ||
4 | &run, | ||
5 | &client_connect_cb, | ||
6 | &client_disconnect_cb, | ||
7 | NULL, | ||
8 | GNUNET_MQ_hd_fixed_size (...), | ||
9 | GNUNET_MQ_hd_var_size (...), | ||
10 | GNUNET_MQ_handler_end ()); | ||
diff --git a/doc/documentation/tutorial-examples/008.c b/doc/documentation/tutorial-examples/008.c new file mode 100644 index 000000000..2dffe2cf9 --- /dev/null +++ b/doc/documentation/tutorial-examples/008.c | |||
@@ -0,0 +1,22 @@ | |||
1 | static void | ||
2 | run (void *cls, | ||
3 | const struct GNUNET_CONFIGURATION_Handle *c, | ||
4 | struct GNUNET_SERVICE_Handle *service) | ||
5 | { | ||
6 | } | ||
7 | |||
8 | static void * | ||
9 | client_connect_cb (void *cls, | ||
10 | struct GNUNET_SERVICE_Client *c, | ||
11 | struct GNUNET_MQ_Handle *mq) | ||
12 | { | ||
13 | return c; | ||
14 | } | ||
15 | |||
16 | static void | ||
17 | client_disconnect_cb (void *cls, | ||
18 | struct GNUNET_SERVICE_Client *c, | ||
19 | void *internal_cls) | ||
20 | { | ||
21 | GNUNET_assert (c == internal_cls); | ||
22 | } | ||
diff --git a/doc/documentation/tutorial-examples/009.c b/doc/documentation/tutorial-examples/009.c new file mode 100644 index 000000000..26d918fb0 --- /dev/null +++ b/doc/documentation/tutorial-examples/009.c | |||
@@ -0,0 +1,9 @@ | |||
1 | #include <gnunet/gnunet_core_service.h> | ||
2 | |||
3 | struct GNUNET_CORE_Handle * | ||
4 | GNUNET_CORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg, | ||
5 | void *cls, | ||
6 | GNUNET_CORE_StartupCallback init, | ||
7 | GNUNET_CORE_ConnectEventHandler connects, | ||
8 | GNUNET_CORE_DisconnectEventHandler disconnects, | ||
9 | const struct GNUNET_MQ_MessageHandler *handlers); | ||
diff --git a/doc/documentation/tutorial-examples/010.c b/doc/documentation/tutorial-examples/010.c new file mode 100644 index 000000000..33494490d --- /dev/null +++ b/doc/documentation/tutorial-examples/010.c | |||
@@ -0,0 +1,8 @@ | |||
1 | void * | ||
2 | connects (void *cls, | ||
3 | const struct GNUNET_PeerIdentity *peer, | ||
4 | struct GNUNET_MQ_Handle *mq) | ||
5 | { | ||
6 | return mq; | ||
7 | } | ||
8 | |||
diff --git a/doc/documentation/tutorial-examples/011.c b/doc/documentation/tutorial-examples/011.c new file mode 100644 index 000000000..23bc051de --- /dev/null +++ b/doc/documentation/tutorial-examples/011.c | |||
@@ -0,0 +1,8 @@ | |||
1 | void | ||
2 | disconnects (void *cls, | ||
3 | const struct GNUNET_PeerIdentity * peer) | ||
4 | { | ||
5 | /* Remove peer's identity from known peers */ | ||
6 | /* Make sure no messages are sent to peer from now on */ | ||
7 | } | ||
8 | |||
diff --git a/doc/documentation/tutorial-examples/012.c b/doc/documentation/tutorial-examples/012.c new file mode 100644 index 000000000..cb21d78ab --- /dev/null +++ b/doc/documentation/tutorial-examples/012.c | |||
@@ -0,0 +1,4 @@ | |||
1 | #include "gnunet_peerstore_service.h" | ||
2 | |||
3 | peerstore_handle = GNUNET_PEERSTORE_connect (cfg); | ||
4 | |||
diff --git a/doc/documentation/tutorial-examples/013.1.c b/doc/documentation/tutorial-examples/013.1.c new file mode 100644 index 000000000..fa5212868 --- /dev/null +++ b/doc/documentation/tutorial-examples/013.1.c | |||
@@ -0,0 +1,3 @@ | |||
1 | void | ||
2 | GNUNET_PEERSTORE_store_cancel (struct GNUNET_PEERSTORE_StoreContext | ||
3 | *sc); | ||
diff --git a/doc/documentation/tutorial-examples/013.c b/doc/documentation/tutorial-examples/013.c new file mode 100644 index 000000000..6792417e1 --- /dev/null +++ b/doc/documentation/tutorial-examples/013.c | |||
@@ -0,0 +1,12 @@ | |||
1 | struct GNUNET_PEERSTORE_StoreContext * | ||
2 | GNUNET_PEERSTORE_store (struct GNUNET_PEERSTORE_Handle *h, | ||
3 | const char *sub_system, | ||
4 | const struct GNUNET_PeerIdentity *peer, | ||
5 | const char *key, | ||
6 | const void *value, | ||
7 | size_t size, | ||
8 | struct GNUNET_TIME_Absolute expiry, | ||
9 | enum GNUNET_PEERSTORE_StoreOption options, | ||
10 | GNUNET_PEERSTORE_Continuation cont, | ||
11 | void *cont_cls); | ||
12 | |||
diff --git a/doc/documentation/tutorial-examples/014.c b/doc/documentation/tutorial-examples/014.c new file mode 100644 index 000000000..ce204f795 --- /dev/null +++ b/doc/documentation/tutorial-examples/014.c | |||
@@ -0,0 +1,9 @@ | |||
1 | struct GNUNET_PEERSTORE_IterateContext * | ||
2 | GNUNET_PEERSTORE_iterate (struct GNUNET_PEERSTORE_Handle *h, | ||
3 | const char *sub_system, | ||
4 | const struct GNUNET_PeerIdentity *peer, | ||
5 | const char *key, | ||
6 | struct GNUNET_TIME_Relative timeout, | ||
7 | GNUNET_PEERSTORE_Processor callback, | ||
8 | void *callback_cls); | ||
9 | |||
diff --git a/doc/documentation/tutorial-examples/015.c b/doc/documentation/tutorial-examples/015.c new file mode 100644 index 000000000..0dd267e8e --- /dev/null +++ b/doc/documentation/tutorial-examples/015.c | |||
@@ -0,0 +1,8 @@ | |||
1 | struct GNUNET_PEERSTORE_WatchContext * | ||
2 | GNUNET_PEERSTORE_watch (struct GNUNET_PEERSTORE_Handle *h, | ||
3 | const char *sub_system, | ||
4 | const struct GNUNET_PeerIdentity *peer, | ||
5 | const char *key, | ||
6 | GNUNET_PEERSTORE_Processor callback, | ||
7 | void *callback_cls); | ||
8 | |||
diff --git a/doc/documentation/tutorial-examples/016.c b/doc/documentation/tutorial-examples/016.c new file mode 100644 index 000000000..d169da16d --- /dev/null +++ b/doc/documentation/tutorial-examples/016.c | |||
@@ -0,0 +1,4 @@ | |||
1 | void | ||
2 | GNUNET_PEERSTORE_watch_cancel (struct GNUNET_PEERSTORE_WatchContext | ||
3 | *wc); | ||
4 | |||
diff --git a/doc/documentation/tutorial-examples/017.c b/doc/documentation/tutorial-examples/017.c new file mode 100644 index 000000000..c86fbcd1f --- /dev/null +++ b/doc/documentation/tutorial-examples/017.c | |||
@@ -0,0 +1,4 @@ | |||
1 | void | ||
2 | GNUNET_PEERSTORE_disconnect (struct GNUNET_PEERSTORE_Handle *h, | ||
3 | int sync_first); | ||
4 | |||
diff --git a/doc/documentation/tutorial-examples/018.c b/doc/documentation/tutorial-examples/018.c new file mode 100644 index 000000000..3fc22584c --- /dev/null +++ b/doc/documentation/tutorial-examples/018.c | |||
@@ -0,0 +1,2 @@ | |||
1 | dht_handle = GNUNET_DHT_connect (cfg, parallel_requests); | ||
2 | |||
diff --git a/doc/documentation/tutorial-examples/019.c b/doc/documentation/tutorial-examples/019.c new file mode 100644 index 000000000..aaf001516 --- /dev/null +++ b/doc/documentation/tutorial-examples/019.c | |||
@@ -0,0 +1,18 @@ | |||
1 | message_sent_cont (void *cls, | ||
2 | const struct GNUNET_SCHEDULER_TaskContext *tc) | ||
3 | { | ||
4 | // Request has left local node | ||
5 | } | ||
6 | |||
7 | struct GNUNET_DHT_PutHandle * | ||
8 | GNUNET_DHT_put (struct GNUNET_DHT_Handle *handle, | ||
9 | const struct GNUNET_HashCode *key, | ||
10 | uint32_t desired_replication_level, | ||
11 | enum GNUNET_DHT_RouteOption options, | ||
12 | enum GNUNET_BLOCK_Type type, | ||
13 | size_t size, | ||
14 | const void *data, | ||
15 | struct GNUNET_TIME_Absolute exp, | ||
16 | struct GNUNET_TIME_Relative timeout, | ||
17 | GNUNET_DHT_PutContinuation cont, void *cont_cls) | ||
18 | |||
diff --git a/doc/documentation/tutorial-examples/020.c b/doc/documentation/tutorial-examples/020.c new file mode 100644 index 000000000..596db3069 --- /dev/null +++ b/doc/documentation/tutorial-examples/020.c | |||
@@ -0,0 +1,25 @@ | |||
1 | static void | ||
2 | get_result_iterator (void *cls, struct GNUNET_TIME_Absolute expiration, | ||
3 | const struct GNUNET_HashCode *key, | ||
4 | const struct GNUNET_PeerIdentity *get_path, | ||
5 | unsigned int get_path_length, | ||
6 | const struct GNUNET_PeerIdentity *put_path, | ||
7 | unsigned int put_path_length, | ||
8 | enum GNUNET_BLOCK_Type type, size_t size, | ||
9 | const void *data) | ||
10 | { | ||
11 | // Optionally: | ||
12 | GNUNET_DHT_get_stop (get_handle); | ||
13 | } | ||
14 | |||
15 | get_handle = | ||
16 | GNUNET_DHT_get_start (dht_handle, | ||
17 | block_type, | ||
18 | &key, | ||
19 | replication, | ||
20 | GNUNET_DHT_RO_NONE, | ||
21 | NULL, | ||
22 | 0, | ||
23 | &get_result_iterator, | ||
24 | cls) | ||
25 | |||
diff --git a/doc/documentation/tutorial-examples/021.c b/doc/documentation/tutorial-examples/021.c new file mode 100644 index 000000000..688a31fe0 --- /dev/null +++ b/doc/documentation/tutorial-examples/021.c | |||
@@ -0,0 +1,13 @@ | |||
1 | static enum GNUNET_BLOCK_EvaluationResult | ||
2 | block_plugin_SERVICE_evaluate (void *cls, | ||
3 | enum GNUNET_BLOCK_Type type, | ||
4 | struct GNUNET_BlockGroup *bg, | ||
5 | const GNUNET_HashCode *query, | ||
6 | const void *xquery, | ||
7 | size_t xquery_size, | ||
8 | const void *reply_block, | ||
9 | size_t reply_block_size) | ||
10 | { | ||
11 | // Verify type, block and bg | ||
12 | } | ||
13 | |||
diff --git a/doc/documentation/tutorial-examples/022.c b/doc/documentation/tutorial-examples/022.c new file mode 100644 index 000000000..a373619bd --- /dev/null +++ b/doc/documentation/tutorial-examples/022.c | |||
@@ -0,0 +1,8 @@ | |||
1 | static int | ||
2 | block_plugin_SERVICE_get_key (void *cls, enum GNUNET_BLOCK_Type type, | ||
3 | const void *block, size_t block_size, | ||
4 | struct GNUNET_HashCode *key) | ||
5 | { | ||
6 | // Store the key in the key argument, return GNUNET_OK on success. | ||
7 | } | ||
8 | |||
diff --git a/doc/documentation/tutorial-examples/023.c b/doc/documentation/tutorial-examples/023.c new file mode 100644 index 000000000..820c38b10 --- /dev/null +++ b/doc/documentation/tutorial-examples/023.c | |||
@@ -0,0 +1,17 @@ | |||
1 | void * | ||
2 | libgnunet_plugin_block_SERVICE_init (void *cls) | ||
3 | { | ||
4 | static enum GNUNET_BLOCK_Type types[] = | ||
5 | { | ||
6 | GNUNET_BLOCK_TYPE_SERVICE_BLOCKYPE, | ||
7 | GNUNET_BLOCK_TYPE_ANY | ||
8 | }; | ||
9 | struct GNUNET_BLOCK_PluginFunctions *api; | ||
10 | |||
11 | api = GNUNET_new (struct GNUNET_BLOCK_PluginFunctions); | ||
12 | api->evaluate = &block_plugin_SERICE_evaluate; | ||
13 | api->get_key = &block_plugin_SERVICE_get_key; | ||
14 | api->types = types; | ||
15 | return api; | ||
16 | } | ||
17 | |||
diff --git a/doc/documentation/tutorial-examples/024.c b/doc/documentation/tutorial-examples/024.c new file mode 100644 index 000000000..2e84b5905 --- /dev/null +++ b/doc/documentation/tutorial-examples/024.c | |||
@@ -0,0 +1,9 @@ | |||
1 | void * | ||
2 | libgnunet_plugin_block_SERVICE_done (void *cls) | ||
3 | { | ||
4 | struct GNUNET_TRANSPORT_PluginFunctions *api = cls; | ||
5 | |||
6 | GNUNET_free (api); | ||
7 | return NULL; | ||
8 | } | ||
9 | |||
diff --git a/doc/documentation/tutorial-examples/025.c b/doc/documentation/tutorial-examples/025.c new file mode 100644 index 000000000..66d4f80ec --- /dev/null +++ b/doc/documentation/tutorial-examples/025.c | |||
@@ -0,0 +1,15 @@ | |||
1 | plugindir = $(libdir)/gnunet | ||
2 | |||
3 | plugin_LTLIBRARIES = \ | ||
4 | libgnunet_plugin_block_ext.la | ||
5 | libgnunet_plugin_block_ext_la_SOURCES = \ | ||
6 | plugin_block_ext.c | ||
7 | libgnunet_plugin_block_ext_la_LIBADD = \ | ||
8 | $(prefix)/lib/libgnunethello.la \ | ||
9 | $(prefix)/lib/libgnunetblock.la \ | ||
10 | $(prefix)/lib/libgnunetutil.la | ||
11 | libgnunet_plugin_block_ext_la_LDFLAGS = \ | ||
12 | $(GN_PLUGIN_LDFLAGS) | ||
13 | libgnunet_plugin_block_ext_la_DEPENDENCIES = \ | ||
14 | $(prefix)/lib/libgnunetblock.la | ||
15 | |||
diff --git a/doc/documentation/tutorial-examples/026.c b/doc/documentation/tutorial-examples/026.c new file mode 100644 index 000000000..264e0b6b9 --- /dev/null +++ b/doc/documentation/tutorial-examples/026.c | |||
@@ -0,0 +1,52 @@ | |||
1 | static void | ||
2 | get_callback (void *cls, | ||
3 | enum GNUNET_DHT_RouteOption options, | ||
4 | enum GNUNET_BLOCK_Type type, | ||
5 | uint32_t hop_count, | ||
6 | uint32_t desired_replication_level, | ||
7 | unsigned int path_length, | ||
8 | const struct GNUNET_PeerIdentity *path, | ||
9 | const struct GNUNET_HashCode * key) | ||
10 | { | ||
11 | } | ||
12 | |||
13 | |||
14 | static void | ||
15 | get_resp_callback (void *cls, | ||
16 | enum GNUNET_BLOCK_Type type, | ||
17 | const struct GNUNET_PeerIdentity *get_path, | ||
18 | unsigned int get_path_length, | ||
19 | const struct GNUNET_PeerIdentity *put_path, | ||
20 | unsigned int put_path_length, | ||
21 | struct GNUNET_TIME_Absolute exp, | ||
22 | const struct GNUNET_HashCode * key, | ||
23 | const void *data, | ||
24 | size_t size) | ||
25 | { | ||
26 | } | ||
27 | |||
28 | |||
29 | static void | ||
30 | put_callback (void *cls, | ||
31 | enum GNUNET_DHT_RouteOption options, | ||
32 | enum GNUNET_BLOCK_Type type, | ||
33 | uint32_t hop_count, | ||
34 | uint32_t desired_replication_level, | ||
35 | unsigned int path_length, | ||
36 | const struct GNUNET_PeerIdentity *path, | ||
37 | struct GNUNET_TIME_Absolute exp, | ||
38 | const struct GNUNET_HashCode * key, | ||
39 | const void *data, | ||
40 | size_t size) | ||
41 | { | ||
42 | } | ||
43 | |||
44 | |||
45 | monitor_handle = GNUNET_DHT_monitor_start (dht_handle, | ||
46 | block_type, | ||
47 | key, | ||
48 | &get_callback, | ||
49 | &get_resp_callback, | ||
50 | &put_callback, | ||
51 | cls); | ||
52 | |||