diff options
Diffstat (limited to 'src/exit')
-rw-r--r-- | src/exit/.gitignore | 2 | ||||
-rw-r--r-- | src/exit/Makefile.am | 38 | ||||
-rw-r--r-- | src/exit/exit.conf | 68 | ||||
-rw-r--r-- | src/exit/exit.h | 298 | ||||
-rw-r--r-- | src/exit/gnunet-daemon-exit.c | 4125 | ||||
-rw-r--r-- | src/exit/gnunet-helper-exit.c | 859 |
6 files changed, 0 insertions, 5390 deletions
diff --git a/src/exit/.gitignore b/src/exit/.gitignore deleted file mode 100644 index 9b75bba9a..000000000 --- a/src/exit/.gitignore +++ /dev/null | |||
@@ -1,2 +0,0 @@ | |||
1 | gnunet-helper-exit | ||
2 | gnunet-daemon-exit | ||
diff --git a/src/exit/Makefile.am b/src/exit/Makefile.am deleted file mode 100644 index c0323d0d6..000000000 --- a/src/exit/Makefile.am +++ /dev/null | |||
@@ -1,38 +0,0 @@ | |||
1 | # This Makefile.am is in the public domain | ||
2 | AM_CPPFLAGS = -I$(top_srcdir)/src/include | ||
3 | |||
4 | if USE_COVERAGE | ||
5 | AM_CFLAGS = --coverage -O0 | ||
6 | endif | ||
7 | |||
8 | pkgcfgdir= $(pkgdatadir)/config.d/ | ||
9 | |||
10 | libexecdir= $(pkglibdir)/libexec/ | ||
11 | |||
12 | plugindir = $(libdir)/gnunet | ||
13 | |||
14 | dist_pkgcfg_DATA = \ | ||
15 | exit.conf | ||
16 | |||
17 | if LINUX | ||
18 | EXITBIN = gnunet-helper-exit | ||
19 | endif | ||
20 | |||
21 | |||
22 | libexec_PROGRAMS = \ | ||
23 | gnunet-daemon-exit \ | ||
24 | $(EXITBIN) | ||
25 | |||
26 | |||
27 | gnunet_helper_exit_SOURCES = \ | ||
28 | gnunet-helper-exit.c | ||
29 | |||
30 | gnunet_daemon_exit_SOURCES = \ | ||
31 | gnunet-daemon-exit.c exit.h | ||
32 | gnunet_daemon_exit_LDADD = \ | ||
33 | $(top_builddir)/src/dht/libgnunetdht.la \ | ||
34 | $(top_builddir)/src/statistics/libgnunetstatistics.la \ | ||
35 | $(top_builddir)/src/util/libgnunetutil.la \ | ||
36 | $(top_builddir)/src/cadet/libgnunetcadet.la \ | ||
37 | $(top_builddir)/src/regex/libgnunetregex.la \ | ||
38 | $(GN_LIBINTL) | ||
diff --git a/src/exit/exit.conf b/src/exit/exit.conf deleted file mode 100644 index 829c5bf80..000000000 --- a/src/exit/exit.conf +++ /dev/null | |||
@@ -1,68 +0,0 @@ | |||
1 | [exit] | ||
2 | BINARY = gnunet-daemon-exit | ||
3 | |||
4 | # IPv6 address for the TUN interface (must be changed as this | ||
5 | # must be within the global IPv6 range of your system!) | ||
6 | IPV6ADDR = 2001:DB8::1 | ||
7 | |||
8 | # Prefix for our IPv6 subnet on the TUN interface. | ||
9 | IPV6PREFIX = 64 | ||
10 | |||
11 | # IPv4 address to use on our TUN interface (may need to be | ||
12 | # changed to avoid conflicts with existing addresses on your system). | ||
13 | # Use RFC 3927-style link-local address | ||
14 | IPV4ADDR = 169.254.86.1 | ||
15 | |||
16 | # Netmask for the IPv4 subnet on the TUN interface. | ||
17 | IPV4MASK = 255.255.255.0 | ||
18 | |||
19 | # IPv4 networks to which we are allowed to exit. | ||
20 | # The format is "(network[/netmask][:[!]SPORT-DPORT];)*" | ||
21 | EXIT_RANGE_IPV4_POLICY = 0.0.0.0/0:!25; | ||
22 | |||
23 | # IPv6 networks to which we are allowed to exit. | ||
24 | # The format is "(network[/netmask][:[!]SPORT-DPORT];)*" | ||
25 | EXIT_RANGE_IPV6_POLICY = ::/0:!25; | ||
26 | |||
27 | # Not a service, tell ARM no binding! | ||
28 | NOARMBIND = YES | ||
29 | |||
30 | # Name of the (virtual) tunnel interface the exit daemon will manage | ||
31 | TUN_IFNAME = exit-gnunet | ||
32 | |||
33 | # Name of the "real" interface that IPv4 traffic from this system will | ||
34 | # leave from; this is the name of the interface where we need to | ||
35 | # enable NAT on postrouting (typically something like 'eth0' or 'eth1' | ||
36 | # or 'wlan0'). Not needed if EXIT_IPv4 is disabled AND if all | ||
37 | # offered services run on 'localhost'. In this case, the value | ||
38 | # of the option can instead be set to "%" (to not enable NAT on any | ||
39 | # interface). | ||
40 | EXIT_IFNAME = eth0 | ||
41 | |||
42 | # Set this to YES to allow exiting this system via IPv4 to the Internet | ||
43 | EXIT_IPV4 = NO | ||
44 | |||
45 | # Set this to YES to allow exiting this system via IPv6 to the Internet | ||
46 | EXIT_IPV6 = NO | ||
47 | |||
48 | # This option should be set to YES to allow the DNS service to | ||
49 | # perform lookups against the locally configured DNS resolver. | ||
50 | # (set to "NO" if no normal ISP is locally available and thus | ||
51 | # requests for normal ".com"/".org"/etc. must be routed via | ||
52 | # the GNUnet VPN (the GNUNET PT daemon then needs to be configured | ||
53 | # to intercept and route DNS queries via cadet). | ||
54 | # Set this to YES to allow using this system for DNS queries. | ||
55 | EXIT_DNS = NO | ||
56 | |||
57 | # Set this to an IPv4 or IPv6 address of a DNS resolver to use for DNS queries | ||
58 | DNS_RESOLVER = 8.8.8.8 | ||
59 | |||
60 | # For IPv4-services offered by this peer, we need to at least enable IPv4 | ||
61 | ENABLE_IPV4 = YES | ||
62 | |||
63 | # For IPv6-services offered by this peer, we need to at least enable IPv6 | ||
64 | ENABLE_IPV6 = YES | ||
65 | |||
66 | |||
67 | # Maximum number of concurrent connections this exit supports. | ||
68 | MAX_CONNECTIONS = 256 | ||
diff --git a/src/exit/exit.h b/src/exit/exit.h deleted file mode 100644 index 41dad6246..000000000 --- a/src/exit/exit.h +++ /dev/null | |||
@@ -1,298 +0,0 @@ | |||
1 | /* | ||
2 | This file is part of GNUnet. | ||
3 | Copyright (C) 2012 Christian Grothoff | ||
4 | |||
5 | GNUnet is free software: you can redistribute it and/or modify it | ||
6 | under the terms of the GNU Affero General Public License as published | ||
7 | by the Free Software Foundation, either version 3 of the License, | ||
8 | or (at your option) any later version. | ||
9 | |||
10 | GNUnet is distributed in the hope that it will be useful, but | ||
11 | WITHOUT ANY WARRANTY; without even the implied warranty of | ||
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
13 | Affero General Public License for more details. | ||
14 | |||
15 | You should have received a copy of the GNU Affero General Public License | ||
16 | along with this program. If not, see <http://www.gnu.org/licenses/>. | ||
17 | |||
18 | SPDX-License-Identifier: AGPL3.0-or-later | ||
19 | */ | ||
20 | |||
21 | /** | ||
22 | * @file exit/exit.h | ||
23 | * @brief format for cadet messages exchanged between VPN service and exit daemon | ||
24 | * @author Christian Grothoff | ||
25 | */ | ||
26 | #ifndef EXIT_H | ||
27 | #define EXIT_H | ||
28 | |||
29 | #include "gnunet_util_lib.h" | ||
30 | |||
31 | GNUNET_NETWORK_STRUCT_BEGIN | ||
32 | |||
33 | /** | ||
34 | * Message send via cadet to an exit daemon to initiate forwarding of | ||
35 | * TCP data to a local service. | ||
36 | */ | ||
37 | struct GNUNET_EXIT_TcpServiceStartMessage | ||
38 | { | ||
39 | /** | ||
40 | * Type is #GNUNET_MESSAGE_TYPE_VPN_TCP_TO_SERVICE_START | ||
41 | */ | ||
42 | struct GNUNET_MessageHeader header; | ||
43 | |||
44 | /** | ||
45 | * Always 0. | ||
46 | */ | ||
47 | uint32_t reserved GNUNET_PACKED; | ||
48 | |||
49 | /** | ||
50 | * Skeleton of the TCP header to send. Port numbers are to | ||
51 | * be replaced and the checksum may be updated as necessary. | ||
52 | */ | ||
53 | struct GNUNET_TUN_TcpHeader tcp_header; | ||
54 | |||
55 | /* followed by TCP payload */ | ||
56 | }; | ||
57 | |||
58 | |||
59 | /** | ||
60 | * Message send via cadet to an exit daemon to initiate forwarding of | ||
61 | * TCP data to the Internet. | ||
62 | */ | ||
63 | struct GNUNET_EXIT_TcpInternetStartMessage | ||
64 | { | ||
65 | /** | ||
66 | * Type is #GNUNET_MESSAGE_TYPE_VPN_TCP_TO_INTERNET_START | ||
67 | */ | ||
68 | struct GNUNET_MessageHeader header; | ||
69 | |||
70 | /** | ||
71 | * Address family, AF_INET or AF_INET6, in network byte order. | ||
72 | */ | ||
73 | int32_t af GNUNET_PACKED; | ||
74 | |||
75 | /** | ||
76 | * Skeleton of the TCP header to send. Port numbers are to | ||
77 | * be replaced and the checksum may be updated as necessary. | ||
78 | */ | ||
79 | struct GNUNET_TUN_TcpHeader tcp_header; | ||
80 | |||
81 | /* followed by IP address of the destination; either | ||
82 | 'struct in_addr' or 'struct in6_addr', depending on af */ | ||
83 | |||
84 | /* followed by TCP payload */ | ||
85 | }; | ||
86 | |||
87 | |||
88 | /** | ||
89 | * Message send via cadet between VPN and entry and an exit daemon to | ||
90 | * transmit TCP data between the VPN entry and an exit session. This | ||
91 | * format is used for both Internet-exits and service-exits and | ||
92 | * in both directions (VPN to exit and exit to VPN). | ||
93 | */ | ||
94 | struct GNUNET_EXIT_TcpDataMessage | ||
95 | { | ||
96 | /** | ||
97 | * Type is #GNUNET_MESSAGE_TYPE_VPN_TCP_DATA | ||
98 | */ | ||
99 | struct GNUNET_MessageHeader header; | ||
100 | |||
101 | /** | ||
102 | * Always 0. | ||
103 | */ | ||
104 | uint32_t reserved GNUNET_PACKED; | ||
105 | |||
106 | /** | ||
107 | * Skeleton of the TCP header to send. Port numbers are to | ||
108 | * be replaced and the checksum may be updated as necessary. (The destination port number should not be changed, as it contains the desired destination port.) | ||
109 | */ | ||
110 | struct GNUNET_TUN_TcpHeader tcp_header; | ||
111 | |||
112 | /* followed by TCP payload */ | ||
113 | }; | ||
114 | |||
115 | |||
116 | /** | ||
117 | * Message send via cadet to an exit daemon to send | ||
118 | * UDP data to a local service. | ||
119 | */ | ||
120 | struct GNUNET_EXIT_UdpServiceMessage | ||
121 | { | ||
122 | /** | ||
123 | * Type is #GNUNET_MESSAGE_TYPE_VPN_UDP_TO_SERVICE | ||
124 | */ | ||
125 | struct GNUNET_MessageHeader header; | ||
126 | |||
127 | /** | ||
128 | * Source port to use for the UDP request (0 to use a random port). In NBO. | ||
129 | */ | ||
130 | uint16_t source_port GNUNET_PACKED; | ||
131 | |||
132 | /** | ||
133 | * Destination port to use for the UDP request. In NBO. | ||
134 | */ | ||
135 | uint16_t destination_port GNUNET_PACKED; | ||
136 | |||
137 | /* followed by UDP payload */ | ||
138 | }; | ||
139 | |||
140 | |||
141 | /** | ||
142 | * Message send via cadet to an exit daemon to forward | ||
143 | * UDP data to the Internet. | ||
144 | */ | ||
145 | struct GNUNET_EXIT_UdpInternetMessage | ||
146 | { | ||
147 | /** | ||
148 | * Type is #GNUNET_MESSAGE_TYPE_VPN_UDP_TO_INTERNET | ||
149 | */ | ||
150 | struct GNUNET_MessageHeader header; | ||
151 | |||
152 | /** | ||
153 | * Address family, AF_INET or AF_INET6, in network byte order. | ||
154 | */ | ||
155 | int32_t af GNUNET_PACKED; | ||
156 | |||
157 | /** | ||
158 | * Source port to use for the UDP request (0 to use a random port). In NBO. | ||
159 | */ | ||
160 | uint16_t source_port GNUNET_PACKED; | ||
161 | |||
162 | /** | ||
163 | * Destination port to use for the UDP request. In NBO. | ||
164 | */ | ||
165 | uint16_t destination_port GNUNET_PACKED; | ||
166 | |||
167 | /* followed by IP address of the destination; either | ||
168 | 'struct in_addr' or 'struct in6_addr', depending on af */ | ||
169 | |||
170 | /* followed by UDP payload */ | ||
171 | }; | ||
172 | |||
173 | |||
174 | /** | ||
175 | * Message send from exit daemon back to the UDP entry point | ||
176 | * (used for both Internet and Service exit replies). | ||
177 | */ | ||
178 | struct GNUNET_EXIT_UdpReplyMessage | ||
179 | { | ||
180 | /** | ||
181 | * Type is #GNUNET_MESSAGE_TYPE_VPN_UDP_REPLY | ||
182 | */ | ||
183 | struct GNUNET_MessageHeader header; | ||
184 | |||
185 | /** | ||
186 | * Source port to use for the UDP reply (0 to use the same | ||
187 | * port as for the original request). In NBO. | ||
188 | */ | ||
189 | uint16_t source_port GNUNET_PACKED; | ||
190 | |||
191 | /** | ||
192 | * Destination port to use for the UDP reply (0 to use the same | ||
193 | * port as for the original request). In NBO. | ||
194 | */ | ||
195 | uint16_t destination_port GNUNET_PACKED; | ||
196 | |||
197 | /* followed by UDP payload */ | ||
198 | }; | ||
199 | |||
200 | |||
201 | /** | ||
202 | * Message send via cadet to an exit daemon to send | ||
203 | * ICMP data to a local service. | ||
204 | */ | ||
205 | struct GNUNET_EXIT_IcmpServiceMessage | ||
206 | { | ||
207 | /** | ||
208 | * Type is #GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_SERVICE | ||
209 | */ | ||
210 | struct GNUNET_MessageHeader header; | ||
211 | |||
212 | /** | ||
213 | * Address family, AF_INET or AF_INET6, in network byte order. This | ||
214 | * AF value determines if the 'icmp_header' is ICMPv4 or ICMPv6. | ||
215 | * The receiver (exit) may still have to translate (PT) to the services' | ||
216 | * ICMP version (if possible). | ||
217 | */ | ||
218 | int32_t af GNUNET_PACKED; | ||
219 | |||
220 | /** | ||
221 | * ICMP header to use. | ||
222 | */ | ||
223 | struct GNUNET_TUN_IcmpHeader icmp_header; | ||
224 | |||
225 | /* followed by ICMP payload; however, for certain ICMP message | ||
226 | types where the payload is the original IP packet, the payload | ||
227 | is omitted as it is useless for the receiver (who will need | ||
228 | to create some fake payload manually) */ | ||
229 | }; | ||
230 | |||
231 | |||
232 | /** | ||
233 | * Message send via cadet to an exit daemon to forward | ||
234 | * ICMP data to the Internet. | ||
235 | */ | ||
236 | struct GNUNET_EXIT_IcmpInternetMessage | ||
237 | { | ||
238 | /** | ||
239 | * Type is #GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_INTERNET | ||
240 | */ | ||
241 | struct GNUNET_MessageHeader header; | ||
242 | |||
243 | /** | ||
244 | * Address family, AF_INET or AF_INET6, in network byte order. | ||
245 | * Determines both the ICMP version used in the 'icmp_header' and | ||
246 | * the IP address format that is used for the target IP. If | ||
247 | * PT is necessary, the sender has already done it. | ||
248 | */ | ||
249 | int32_t af GNUNET_PACKED; | ||
250 | |||
251 | /** | ||
252 | * ICMP header to use. Must match the target 'af' given | ||
253 | * above. | ||
254 | */ | ||
255 | struct GNUNET_TUN_IcmpHeader icmp_header; | ||
256 | |||
257 | /* followed by IP address of the destination; either | ||
258 | 'struct in_addr' or 'struct in6_addr', depending on af */ | ||
259 | |||
260 | /* followed by ICMP payload; however, for certain ICMP message | ||
261 | types where the payload is the original IP packet, the payload | ||
262 | is omitted as it is useless for the receiver (who will need | ||
263 | to create some fake payload manually) */ | ||
264 | }; | ||
265 | |||
266 | |||
267 | /** | ||
268 | * Message send via cadet to the vpn service to send | ||
269 | * ICMP data to the VPN's TUN interface. | ||
270 | */ | ||
271 | struct GNUNET_EXIT_IcmpToVPNMessage | ||
272 | { | ||
273 | /** | ||
274 | * Type is #GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_VPN | ||
275 | */ | ||
276 | struct GNUNET_MessageHeader header; | ||
277 | |||
278 | /** | ||
279 | * Address family, AF_INET or AF_INET6, in network byte order. | ||
280 | * Useful to determine if this is an ICMPv4 or ICMPv6 header. | ||
281 | */ | ||
282 | int32_t af GNUNET_PACKED; | ||
283 | |||
284 | /** | ||
285 | * ICMP header to use. ICMPv4 or ICMPv6, depending on 'af'. | ||
286 | */ | ||
287 | struct GNUNET_TUN_IcmpHeader icmp_header; | ||
288 | |||
289 | /* followed by ICMP payload; however, for certain ICMP message | ||
290 | types where the payload is the original IP packet, the payload | ||
291 | is omitted as it is useless for the receiver (who will need | ||
292 | to create some fake payload manually) */ | ||
293 | }; | ||
294 | |||
295 | |||
296 | GNUNET_NETWORK_STRUCT_END | ||
297 | |||
298 | #endif | ||
diff --git a/src/exit/gnunet-daemon-exit.c b/src/exit/gnunet-daemon-exit.c deleted file mode 100644 index f4a17e32a..000000000 --- a/src/exit/gnunet-daemon-exit.c +++ /dev/null | |||
@@ -1,4125 +0,0 @@ | |||
1 | /* | ||
2 | This file is part of GNUnet. | ||
3 | Copyright (C) 2010-2013, 2017 Christian Grothoff | ||
4 | |||
5 | GNUnet is free software: you can redistribute it and/or modify it | ||
6 | under the terms of the GNU Affero General Public License as published | ||
7 | by the Free Software Foundation, either version 3 of the License, | ||
8 | or (at your option) any later version. | ||
9 | |||
10 | GNUnet is distributed in the hope that it will be useful, but | ||
11 | WITHOUT ANY WARRANTY; without even the implied warranty of | ||
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
13 | Affero General Public License for more details. | ||
14 | |||
15 | You should have received a copy of the GNU Affero General Public License | ||
16 | along with this program. If not, see <http://www.gnu.org/licenses/>. | ||
17 | |||
18 | SPDX-License-Identifier: AGPL3.0-or-later | ||
19 | */ | ||
20 | |||
21 | /** | ||
22 | * @file exit/gnunet-daemon-exit.c | ||
23 | * @brief tool to allow IP traffic exit from the GNUnet cadet to the Internet | ||
24 | * @author Philipp Toelke | ||
25 | * @author Christian Grothoff | ||
26 | * | ||
27 | * TODO: | ||
28 | * - test | ||
29 | * | ||
30 | * Design: | ||
31 | * - which code should advertise services? the service model is right | ||
32 | * now a bit odd, especially as this code DOES the exit and knows | ||
33 | * the DNS "name", but OTOH this is clearly NOT the place to advertise | ||
34 | * the service's existence; maybe the daemon should turn into a | ||
35 | * service with an API to add local-exit services dynamically? | ||
36 | */ | ||
37 | #include "platform.h" | ||
38 | #include "gnunet_util_lib.h" | ||
39 | #include "gnunet_protocols.h" | ||
40 | #include "gnunet_applications.h" | ||
41 | #include "gnunet_dht_service.h" | ||
42 | #include "gnunet_cadet_service.h" | ||
43 | #include "gnunet_dnsparser_lib.h" | ||
44 | #include "gnunet_dnsstub_lib.h" | ||
45 | #include "gnunet_statistics_service.h" | ||
46 | #include "gnunet_constants.h" | ||
47 | #include "gnunet_signatures.h" | ||
48 | #include "gnunet_tun_lib.h" | ||
49 | #include "gnunet_regex_service.h" | ||
50 | #include "exit.h" | ||
51 | #include "block_dns.h" | ||
52 | |||
53 | |||
54 | /** | ||
55 | * Maximum path compression length for cadet regex announcing for IPv4 address | ||
56 | * based regex. | ||
57 | */ | ||
58 | #define REGEX_MAX_PATH_LEN_IPV4 4 | ||
59 | |||
60 | /** | ||
61 | * Maximum path compression length for cadet regex announcing for IPv6 address | ||
62 | * based regex. | ||
63 | */ | ||
64 | #define REGEX_MAX_PATH_LEN_IPV6 8 | ||
65 | |||
66 | /** | ||
67 | * How frequently do we re-announce the regex for the exit? | ||
68 | */ | ||
69 | #define REGEX_REFRESH_FREQUENCY GNUNET_TIME_relative_multiply ( \ | ||
70 | GNUNET_TIME_UNIT_MINUTES, 30) | ||
71 | |||
72 | /** | ||
73 | * How frequently do we re-announce the DNS exit in the DHT? | ||
74 | */ | ||
75 | #define DHT_PUT_FREQUENCY GNUNET_TIME_relative_multiply ( \ | ||
76 | GNUNET_TIME_UNIT_MINUTES, 15) | ||
77 | |||
78 | /** | ||
79 | * How long do we typically sign the DNS exit advertisement for? | ||
80 | */ | ||
81 | #define DNS_ADVERTISEMENT_TIMEOUT GNUNET_TIME_relative_multiply ( \ | ||
82 | GNUNET_TIME_UNIT_HOURS, 3) | ||
83 | |||
84 | |||
85 | /** | ||
86 | * Generic logging shorthand | ||
87 | */ | ||
88 | #define LOG(kind, ...) \ | ||
89 | GNUNET_log_from (kind, "exit", __VA_ARGS__); | ||
90 | |||
91 | |||
92 | /** | ||
93 | * Information about an address. | ||
94 | */ | ||
95 | struct SocketAddress | ||
96 | { | ||
97 | /** | ||
98 | * AF_INET or AF_INET6. | ||
99 | */ | ||
100 | int af; | ||
101 | |||
102 | /** | ||
103 | * Remote address information. | ||
104 | */ | ||
105 | union | ||
106 | { | ||
107 | /** | ||
108 | * Address, if af is AF_INET. | ||
109 | */ | ||
110 | struct in_addr ipv4; | ||
111 | |||
112 | /** | ||
113 | * Address, if af is AF_INET6. | ||
114 | */ | ||
115 | struct in6_addr ipv6; | ||
116 | } address; | ||
117 | |||
118 | /** | ||
119 | * IPPROTO_TCP or IPPROTO_UDP; | ||
120 | */ | ||
121 | uint8_t proto; | ||
122 | |||
123 | /** | ||
124 | * Remote port, in host byte order! | ||
125 | */ | ||
126 | uint16_t port; | ||
127 | }; | ||
128 | |||
129 | |||
130 | /** | ||
131 | * This struct is saved into the services-hashmap to represent | ||
132 | * a service this peer is specifically offering an exit for | ||
133 | * (for a specific domain name). | ||
134 | */ | ||
135 | struct LocalService | ||
136 | { | ||
137 | /** | ||
138 | * Remote address to use for the service. | ||
139 | */ | ||
140 | struct SocketAddress address; | ||
141 | |||
142 | /** | ||
143 | * Descriptor for the service (CADET port). | ||
144 | */ | ||
145 | struct GNUNET_HashCode descriptor; | ||
146 | |||
147 | /** | ||
148 | * DNS name of the service. | ||
149 | */ | ||
150 | char *name; | ||
151 | |||
152 | /** | ||
153 | * Open port with CADET. | ||
154 | */ | ||
155 | struct GNUNET_CADET_Port *port; | ||
156 | |||
157 | /** | ||
158 | * #GNUNET_YES if this is a UDP service, otherwise TCP. | ||
159 | */ | ||
160 | int16_t is_udp; | ||
161 | }; | ||
162 | |||
163 | |||
164 | /** | ||
165 | * Information we use to track a connection (the classical 6-tuple of | ||
166 | * IP-version, protocol, source-IP, destination-IP, source-port and | ||
167 | * destinatin-port. | ||
168 | */ | ||
169 | struct RedirectInformation | ||
170 | { | ||
171 | /** | ||
172 | * Address information for the other party (equivalent of the | ||
173 | * arguments one would give to "connect"). | ||
174 | */ | ||
175 | struct SocketAddress remote_address; | ||
176 | |||
177 | /** | ||
178 | * Address information we used locally (AF and proto must match | ||
179 | * "remote_address"). Equivalent of the arguments one would give to | ||
180 | * "bind". | ||
181 | */ | ||
182 | struct SocketAddress local_address; | ||
183 | |||
184 | /* | ||
185 | Note 1: additional information might be added here in the | ||
186 | future to support protocols that require special handling, | ||
187 | such as ftp/tftp | ||
188 | |||
189 | Note 2: we might also sometimes not match on all components | ||
190 | of the tuple, to support protocols where things do not always | ||
191 | fully map. | ||
192 | */ | ||
193 | }; | ||
194 | |||
195 | |||
196 | /** | ||
197 | * This struct is saved into #connections_map to allow finding the | ||
198 | * right channel given an IP packet from TUN. It is also associated | ||
199 | * with the channel's closure so we can find it again for the next | ||
200 | * message from the channel. | ||
201 | */ | ||
202 | struct ChannelState | ||
203 | { | ||
204 | /** | ||
205 | * Cadet channel that is used for this connection. | ||
206 | */ | ||
207 | struct GNUNET_CADET_Channel *channel; | ||
208 | |||
209 | /** | ||
210 | * Who is the other end of this channel. | ||
211 | * FIXME is this needed? Only used for debugging messages | ||
212 | */ | ||
213 | struct GNUNET_PeerIdentity peer; | ||
214 | |||
215 | /** | ||
216 | * #GNUNET_NO if this is a channel for TCP/UDP, | ||
217 | * #GNUNET_YES if this is a channel for DNS, | ||
218 | * #GNUNET_SYSERR if the channel is not yet initialized. | ||
219 | */ | ||
220 | int is_dns; | ||
221 | |||
222 | union | ||
223 | { | ||
224 | struct | ||
225 | { | ||
226 | /** | ||
227 | * Heap node for this state in the connections_heap. | ||
228 | */ | ||
229 | struct GNUNET_CONTAINER_HeapNode *heap_node; | ||
230 | |||
231 | /** | ||
232 | * Key this state has in the #connections_map. | ||
233 | */ | ||
234 | struct GNUNET_HashCode state_key; | ||
235 | |||
236 | /** | ||
237 | * Associated service record, or NULL for no service. | ||
238 | */ | ||
239 | struct LocalService *serv; | ||
240 | |||
241 | /** | ||
242 | * Primary redirection information for this connection. | ||
243 | */ | ||
244 | struct RedirectInformation ri; | ||
245 | } tcp_udp; | ||
246 | |||
247 | struct | ||
248 | { | ||
249 | /** | ||
250 | * Socket we are using to transmit this request (must match if we receive | ||
251 | * a response). | ||
252 | */ | ||
253 | struct GNUNET_DNSSTUB_RequestSocket *rs; | ||
254 | |||
255 | /** | ||
256 | * Original DNS request ID as used by the client. | ||
257 | */ | ||
258 | uint16_t original_id; | ||
259 | |||
260 | /** | ||
261 | * DNS request ID that we used for forwarding. | ||
262 | */ | ||
263 | uint16_t my_id; | ||
264 | } dns; | ||
265 | } specifics; | ||
266 | }; | ||
267 | |||
268 | |||
269 | /** | ||
270 | * Return value from 'main'. | ||
271 | */ | ||
272 | static int global_ret; | ||
273 | |||
274 | /** | ||
275 | * Handle to our regex announcement for IPv4. | ||
276 | */ | ||
277 | static struct GNUNET_REGEX_Announcement *regex4; | ||
278 | |||
279 | /** | ||
280 | * Handle to our regex announcement for IPv4. | ||
281 | */ | ||
282 | static struct GNUNET_REGEX_Announcement *regex6; | ||
283 | |||
284 | /** | ||
285 | * The handle to the configuration used throughout the process | ||
286 | */ | ||
287 | static const struct GNUNET_CONFIGURATION_Handle *cfg; | ||
288 | |||
289 | /** | ||
290 | * The handle to the helper | ||
291 | */ | ||
292 | static struct GNUNET_HELPER_Handle *helper_handle; | ||
293 | |||
294 | /** | ||
295 | * Arguments to the exit helper. | ||
296 | */ | ||
297 | static char *exit_argv[8]; | ||
298 | |||
299 | /** | ||
300 | * IPv6 address of our TUN interface. | ||
301 | */ | ||
302 | static struct in6_addr exit_ipv6addr; | ||
303 | |||
304 | /** | ||
305 | * IPv6 prefix (0..127) from configuration file. | ||
306 | */ | ||
307 | static unsigned long long ipv6prefix; | ||
308 | |||
309 | /** | ||
310 | * IPv4 address of our TUN interface. | ||
311 | */ | ||
312 | static struct in_addr exit_ipv4addr; | ||
313 | |||
314 | /** | ||
315 | * IPv4 netmask of our TUN interface. | ||
316 | */ | ||
317 | static struct in_addr exit_ipv4mask; | ||
318 | |||
319 | /** | ||
320 | * Statistics. | ||
321 | */ | ||
322 | static struct GNUNET_STATISTICS_Handle *stats; | ||
323 | |||
324 | /** | ||
325 | * The handle to cadet | ||
326 | */ | ||
327 | static struct GNUNET_CADET_Handle *cadet_handle; | ||
328 | |||
329 | /** | ||
330 | * This hashmaps contains the mapping from peer, service-descriptor, | ||
331 | * source-port and destination-port to a struct ChannelState | ||
332 | */ | ||
333 | static struct GNUNET_CONTAINER_MultiHashMap *connections_map; | ||
334 | |||
335 | /** | ||
336 | * Heap so we can quickly find "old" connections. | ||
337 | */ | ||
338 | static struct GNUNET_CONTAINER_Heap *connections_heap; | ||
339 | |||
340 | /** | ||
341 | * If there are at least this many connections, old ones will be removed | ||
342 | */ | ||
343 | static unsigned long long max_connections; | ||
344 | |||
345 | /** | ||
346 | * This hashmaps saves interesting things about the configured services | ||
347 | */ | ||
348 | static struct GNUNET_CONTAINER_MultiHashMap *services; | ||
349 | |||
350 | /** | ||
351 | * Array of all open DNS requests from channels. | ||
352 | */ | ||
353 | static struct ChannelState *channels[UINT16_MAX + 1]; | ||
354 | |||
355 | /** | ||
356 | * Handle to the DNS Stub resolver. | ||
357 | */ | ||
358 | static struct GNUNET_DNSSTUB_Context *dnsstub; | ||
359 | |||
360 | /** | ||
361 | * Handle for ongoing DHT PUT operations to advertise exit service. | ||
362 | */ | ||
363 | static struct GNUNET_DHT_PutHandle *dht_put; | ||
364 | |||
365 | /** | ||
366 | * Handle to the DHT. | ||
367 | */ | ||
368 | static struct GNUNET_DHT_Handle *dht; | ||
369 | |||
370 | /** | ||
371 | * Task for doing DHT PUTs to advertise exit service. | ||
372 | */ | ||
373 | static struct GNUNET_SCHEDULER_Task *dht_task; | ||
374 | |||
375 | /** | ||
376 | * Advertisement message we put into the DHT to advertise us | ||
377 | * as a DNS exit. | ||
378 | */ | ||
379 | static struct GNUNET_DNS_Advertisement dns_advertisement; | ||
380 | |||
381 | /** | ||
382 | * Key we store the DNS advertismenet under. | ||
383 | */ | ||
384 | static struct GNUNET_HashCode dht_put_key; | ||
385 | |||
386 | /** | ||
387 | * Private key for this peer. | ||
388 | */ | ||
389 | static struct GNUNET_CRYPTO_EddsaPrivateKey *peer_key; | ||
390 | |||
391 | /** | ||
392 | * Port for DNS exit. | ||
393 | */ | ||
394 | static struct GNUNET_CADET_Port *dns_port; | ||
395 | |||
396 | /** | ||
397 | * Port for IPv4 exit. | ||
398 | */ | ||
399 | static struct GNUNET_CADET_Port *cadet_port4; | ||
400 | |||
401 | /** | ||
402 | * Port for IPv6 exit. | ||
403 | */ | ||
404 | static struct GNUNET_CADET_Port *cadet_port6; | ||
405 | |||
406 | /** | ||
407 | * Are we an IPv4-exit? | ||
408 | */ | ||
409 | static int ipv4_exit; | ||
410 | |||
411 | /** | ||
412 | * Are we an IPv6-exit? | ||
413 | */ | ||
414 | static int ipv6_exit; | ||
415 | |||
416 | /** | ||
417 | * Do we support IPv4 at all on the TUN interface? | ||
418 | */ | ||
419 | static int ipv4_enabled; | ||
420 | |||
421 | /** | ||
422 | * Do we support IPv6 at all on the TUN interface? | ||
423 | */ | ||
424 | static int ipv6_enabled; | ||
425 | |||
426 | |||
427 | GNUNET_NETWORK_STRUCT_BEGIN | ||
428 | |||
429 | /** | ||
430 | * Message with a DNS response. | ||
431 | */ | ||
432 | struct DnsResponseMessage | ||
433 | { | ||
434 | /** | ||
435 | * GNUnet header, of type #GNUNET_MESSAGE_TYPE_VPN_DNS_FROM_INTERNET | ||
436 | */ | ||
437 | struct GNUNET_MessageHeader header; | ||
438 | |||
439 | /** | ||
440 | * DNS header. | ||
441 | */ | ||
442 | struct GNUNET_TUN_DnsHeader dns; | ||
443 | |||
444 | /* Followed by more DNS payload */ | ||
445 | }; | ||
446 | |||
447 | GNUNET_NETWORK_STRUCT_END | ||
448 | |||
449 | |||
450 | /** | ||
451 | * Callback called from DNSSTUB resolver when a resolution | ||
452 | * succeeded. | ||
453 | * | ||
454 | * @param cls NULL | ||
455 | * @param dns the response itself | ||
456 | * @param r number of bytes in @a dns | ||
457 | */ | ||
458 | static void | ||
459 | process_dns_result (void *cls, | ||
460 | const struct GNUNET_TUN_DnsHeader *dns, | ||
461 | size_t r) | ||
462 | { | ||
463 | struct ChannelState *ts; | ||
464 | struct GNUNET_MQ_Envelope *env; | ||
465 | struct DnsResponseMessage *resp; | ||
466 | |||
467 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
468 | "Processing DNS result from stub resolver\n"); | ||
469 | GNUNET_assert (NULL == cls); | ||
470 | if (NULL == dns) | ||
471 | return; | ||
472 | /* Handle case that this is a reply to a request from a CADET DNS channel */ | ||
473 | ts = channels[dns->id]; | ||
474 | if (NULL == ts) | ||
475 | return; | ||
476 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
477 | "Got a response from the stub resolver for DNS request received via CADET!\n"); | ||
478 | channels[dns->id] = NULL; | ||
479 | env = GNUNET_MQ_msg_extra (resp, | ||
480 | r - sizeof(struct GNUNET_TUN_DnsHeader), | ||
481 | GNUNET_MESSAGE_TYPE_VPN_DNS_FROM_INTERNET); | ||
482 | GNUNET_memcpy (&resp->dns, | ||
483 | dns, | ||
484 | r); | ||
485 | resp->dns.id = ts->specifics.dns.original_id; | ||
486 | GNUNET_MQ_send (GNUNET_CADET_get_mq (ts->channel), | ||
487 | env); | ||
488 | } | ||
489 | |||
490 | |||
491 | /** | ||
492 | * Check a request via cadet to perform a DNS query. | ||
493 | * | ||
494 | * @param cls our `struct ChannelState *` | ||
495 | * @param msg the actual message | ||
496 | * @return #GNUNET_OK to keep the connection open, | ||
497 | * #GNUNET_SYSERR to close it (signal serious error) | ||
498 | */ | ||
499 | static int | ||
500 | check_dns_request (void *cls, | ||
501 | const struct DnsResponseMessage *msg) | ||
502 | { | ||
503 | struct ChannelState *ts = cls; | ||
504 | |||
505 | if (NULL == dnsstub) | ||
506 | { | ||
507 | GNUNET_break (0); | ||
508 | return GNUNET_SYSERR; | ||
509 | } | ||
510 | if (GNUNET_NO == ts->is_dns) | ||
511 | { | ||
512 | GNUNET_break_op (0); | ||
513 | return GNUNET_SYSERR; | ||
514 | } | ||
515 | return GNUNET_OK; | ||
516 | } | ||
517 | |||
518 | |||
519 | /** | ||
520 | * Process a request via cadet to perform a DNS query. | ||
521 | * | ||
522 | * @param cls our `struct ChannelState *` | ||
523 | * @param msg the actual message | ||
524 | */ | ||
525 | static void | ||
526 | handle_dns_request (void *cls, | ||
527 | const struct DnsResponseMessage *msg) | ||
528 | { | ||
529 | struct ChannelState *ts = cls; | ||
530 | size_t mlen = ntohs (msg->header.size); | ||
531 | size_t dlen = mlen - sizeof(struct GNUNET_MessageHeader); | ||
532 | char buf[dlen] GNUNET_ALIGN; | ||
533 | struct GNUNET_TUN_DnsHeader *dns_out; | ||
534 | |||
535 | if (GNUNET_SYSERR == ts->is_dns) | ||
536 | { | ||
537 | /* channel is DNS from now on */ | ||
538 | ts->is_dns = GNUNET_YES; | ||
539 | } | ||
540 | ts->specifics.dns.original_id = msg->dns.id; | ||
541 | if (channels[ts->specifics.dns.my_id] == ts) | ||
542 | channels[ts->specifics.dns.my_id] = NULL; | ||
543 | ts->specifics.dns.my_id = (uint16_t) GNUNET_CRYPTO_random_u32 ( | ||
544 | GNUNET_CRYPTO_QUALITY_WEAK, | ||
545 | UINT16_MAX | ||
546 | + 1); | ||
547 | channels[ts->specifics.dns.my_id] = ts; | ||
548 | GNUNET_memcpy (buf, | ||
549 | &msg->dns, | ||
550 | dlen); | ||
551 | dns_out = (struct GNUNET_TUN_DnsHeader *) buf; | ||
552 | dns_out->id = ts->specifics.dns.my_id; | ||
553 | ts->specifics.dns.rs = GNUNET_DNSSTUB_resolve (dnsstub, | ||
554 | buf, | ||
555 | dlen, | ||
556 | &process_dns_result, | ||
557 | NULL); | ||
558 | if (NULL == ts->specifics.dns.rs) | ||
559 | { | ||
560 | GNUNET_break_op (0); | ||
561 | return; | ||
562 | } | ||
563 | GNUNET_CADET_receive_done (ts->channel); | ||
564 | } | ||
565 | |||
566 | |||
567 | /** | ||
568 | * Given IP information about a connection, calculate the respective | ||
569 | * hash we would use for the #connections_map. | ||
570 | * | ||
571 | * @param hash resulting hash | ||
572 | * @param ri information about the connection | ||
573 | */ | ||
574 | static void | ||
575 | hash_redirect_info (struct GNUNET_HashCode *hash, | ||
576 | const struct RedirectInformation *ri) | ||
577 | { | ||
578 | char *off; | ||
579 | |||
580 | memset (hash, | ||
581 | 0, | ||
582 | sizeof(struct GNUNET_HashCode)); | ||
583 | /* the GNUnet hashmap only uses the first sizeof(unsigned int) of the hash, | ||
584 | so we put the IP address in there (and hope for few collisions) */ | ||
585 | off = (char *) hash; | ||
586 | switch (ri->remote_address.af) | ||
587 | { | ||
588 | case AF_INET: | ||
589 | GNUNET_memcpy (off, | ||
590 | &ri->remote_address.address.ipv4, | ||
591 | sizeof(struct in_addr)); | ||
592 | off += sizeof(struct in_addr); | ||
593 | break; | ||
594 | |||
595 | case AF_INET6: | ||
596 | GNUNET_memcpy (off, | ||
597 | &ri->remote_address.address.ipv6, | ||
598 | sizeof(struct in6_addr)); | ||
599 | off += sizeof(struct in_addr); | ||
600 | break; | ||
601 | |||
602 | default: | ||
603 | GNUNET_assert (0); | ||
604 | } | ||
605 | GNUNET_memcpy (off, | ||
606 | &ri->remote_address.port, | ||
607 | sizeof(uint16_t)); | ||
608 | off += sizeof(uint16_t); | ||
609 | switch (ri->local_address.af) | ||
610 | { | ||
611 | case AF_INET: | ||
612 | GNUNET_memcpy (off, | ||
613 | &ri->local_address.address.ipv4, | ||
614 | sizeof(struct in_addr)); | ||
615 | off += sizeof(struct in_addr); | ||
616 | break; | ||
617 | |||
618 | case AF_INET6: | ||
619 | GNUNET_memcpy (off, | ||
620 | &ri->local_address.address.ipv6, | ||
621 | sizeof(struct in6_addr)); | ||
622 | off += sizeof(struct in_addr); | ||
623 | break; | ||
624 | |||
625 | default: | ||
626 | GNUNET_assert (0); | ||
627 | } | ||
628 | GNUNET_memcpy (off, | ||
629 | &ri->local_address.port, | ||
630 | sizeof(uint16_t)); | ||
631 | off += sizeof(uint16_t); | ||
632 | GNUNET_memcpy (off, | ||
633 | &ri->remote_address.proto, | ||
634 | sizeof(uint8_t)); | ||
635 | /* off += sizeof (uint8_t); */ | ||
636 | } | ||
637 | |||
638 | |||
639 | /** | ||
640 | * Get our connection tracking state. Warns if it does not exists, | ||
641 | * refreshes the timestamp if it does exist. | ||
642 | * | ||
643 | * @param af address family | ||
644 | * @param protocol IPPROTO_UDP or IPPROTO_TCP | ||
645 | * @param destination_ip target IP | ||
646 | * @param destination_port target port | ||
647 | * @param local_ip local IP | ||
648 | * @param local_port local port | ||
649 | * @param state_key set to hash's state if non-NULL | ||
650 | * @return NULL if we have no tracking information for this tuple | ||
651 | */ | ||
652 | static struct ChannelState * | ||
653 | get_redirect_state (int af, | ||
654 | int protocol, | ||
655 | const void *destination_ip, | ||
656 | uint16_t destination_port, | ||
657 | const void *local_ip, | ||
658 | uint16_t local_port, | ||
659 | struct GNUNET_HashCode *state_key) | ||
660 | { | ||
661 | struct RedirectInformation ri; | ||
662 | struct GNUNET_HashCode key; | ||
663 | struct ChannelState *state; | ||
664 | |||
665 | if (((af == AF_INET) && (protocol == IPPROTO_ICMP)) || | ||
666 | ((af == AF_INET6) && (protocol == IPPROTO_ICMPV6))) | ||
667 | { | ||
668 | /* ignore ports */ | ||
669 | destination_port = 0; | ||
670 | local_port = 0; | ||
671 | } | ||
672 | ri.remote_address.af = af; | ||
673 | if (af == AF_INET) | ||
674 | ri.remote_address.address.ipv4 = *((struct in_addr*) destination_ip); | ||
675 | else | ||
676 | ri.remote_address.address.ipv6 = *((struct in6_addr*) destination_ip); | ||
677 | ri.remote_address.port = destination_port; | ||
678 | ri.remote_address.proto = protocol; | ||
679 | ri.local_address.af = af; | ||
680 | if (af == AF_INET) | ||
681 | ri.local_address.address.ipv4 = *((struct in_addr*) local_ip); | ||
682 | else | ||
683 | ri.local_address.address.ipv6 = *((struct in6_addr*) local_ip); | ||
684 | ri.local_address.port = local_port; | ||
685 | ri.local_address.proto = protocol; | ||
686 | hash_redirect_info (&key, | ||
687 | &ri); | ||
688 | if (NULL != state_key) | ||
689 | *state_key = key; | ||
690 | state = GNUNET_CONTAINER_multihashmap_get (connections_map, | ||
691 | &key); | ||
692 | if (NULL == state) | ||
693 | return NULL; | ||
694 | /* Mark this connection as freshly used */ | ||
695 | if (NULL == state_key) | ||
696 | GNUNET_CONTAINER_heap_update_cost (state->specifics.tcp_udp.heap_node, | ||
697 | GNUNET_TIME_absolute_get ().abs_value_us); | ||
698 | return state; | ||
699 | } | ||
700 | |||
701 | |||
702 | /** | ||
703 | * Check a request via cadet to send a request to a TCP service | ||
704 | * offered by this system. | ||
705 | * | ||
706 | * @param cls our `struct ChannelState *` | ||
707 | * @param start the actual message | ||
708 | * @return #GNUNET_OK to keep the connection open, | ||
709 | * #GNUNET_SYSERR to close it (signal serious error) | ||
710 | */ | ||
711 | static int | ||
712 | check_tcp_service (void *cls, | ||
713 | const struct GNUNET_EXIT_TcpServiceStartMessage *start) | ||
714 | { | ||
715 | struct ChannelState *state = cls; | ||
716 | |||
717 | if (NULL == state) | ||
718 | { | ||
719 | GNUNET_break_op (0); | ||
720 | return GNUNET_SYSERR; | ||
721 | } | ||
722 | if (GNUNET_YES == state->is_dns) | ||
723 | { | ||
724 | GNUNET_break_op (0); | ||
725 | return GNUNET_SYSERR; | ||
726 | } | ||
727 | if (NULL == state->specifics.tcp_udp.serv) | ||
728 | { | ||
729 | GNUNET_break_op (0); | ||
730 | return GNUNET_SYSERR; | ||
731 | } | ||
732 | if (NULL != state->specifics.tcp_udp.heap_node) | ||
733 | { | ||
734 | GNUNET_break_op (0); | ||
735 | return GNUNET_SYSERR; | ||
736 | } | ||
737 | if (start->tcp_header.off * 4 < sizeof(struct GNUNET_TUN_TcpHeader)) | ||
738 | { | ||
739 | GNUNET_break_op (0); | ||
740 | return GNUNET_SYSERR; | ||
741 | } | ||
742 | return GNUNET_OK; | ||
743 | } | ||
744 | |||
745 | |||
746 | /** | ||
747 | * Prepare an IPv4 packet for transmission via the TUN interface. | ||
748 | * Initializes the IP header and calculates checksums (IP+UDP/TCP). | ||
749 | * For UDP, the UDP header will be fully created, whereas for TCP | ||
750 | * only the ports and checksum will be filled in. So for TCP, | ||
751 | * a skeleton TCP header must be part of the provided payload. | ||
752 | * | ||
753 | * @param payload payload of the packet (starting with UDP payload or | ||
754 | * TCP header, depending on protocol) | ||
755 | * @param payload_length number of bytes in @a payload | ||
756 | * @param protocol IPPROTO_UDP or IPPROTO_TCP | ||
757 | * @param tcp_header skeleton of the TCP header, NULL for UDP | ||
758 | * @param src_address source address to use (IP and port) | ||
759 | * @param dst_address destination address to use (IP and port) | ||
760 | * @param pkt4 where to write the assembled packet; must | ||
761 | * contain enough space for the IP header, UDP/TCP header | ||
762 | * AND the payload | ||
763 | */ | ||
764 | static void | ||
765 | prepare_ipv4_packet (const void *payload, | ||
766 | size_t payload_length, | ||
767 | int protocol, | ||
768 | const struct GNUNET_TUN_TcpHeader *tcp_header, | ||
769 | const struct SocketAddress *src_address, | ||
770 | const struct SocketAddress *dst_address, | ||
771 | struct GNUNET_TUN_IPv4Header *pkt4) | ||
772 | { | ||
773 | size_t len; | ||
774 | |||
775 | len = payload_length; | ||
776 | switch (protocol) | ||
777 | { | ||
778 | case IPPROTO_UDP: | ||
779 | len += sizeof(struct GNUNET_TUN_UdpHeader); | ||
780 | break; | ||
781 | |||
782 | case IPPROTO_TCP: | ||
783 | len += sizeof(struct GNUNET_TUN_TcpHeader); | ||
784 | GNUNET_assert (NULL != tcp_header); | ||
785 | break; | ||
786 | |||
787 | default: | ||
788 | GNUNET_break (0); | ||
789 | return; | ||
790 | } | ||
791 | if (len + sizeof(struct GNUNET_TUN_IPv4Header) > UINT16_MAX) | ||
792 | { | ||
793 | GNUNET_break (0); | ||
794 | return; | ||
795 | } | ||
796 | |||
797 | GNUNET_TUN_initialize_ipv4_header (pkt4, | ||
798 | protocol, | ||
799 | len, | ||
800 | &src_address->address.ipv4, | ||
801 | &dst_address->address.ipv4); | ||
802 | switch (protocol) | ||
803 | { | ||
804 | case IPPROTO_UDP: | ||
805 | { | ||
806 | struct GNUNET_TUN_UdpHeader *pkt4_udp = (struct | ||
807 | GNUNET_TUN_UdpHeader *) &pkt4[1]; | ||
808 | |||
809 | pkt4_udp->source_port = htons (src_address->port); | ||
810 | pkt4_udp->destination_port = htons (dst_address->port); | ||
811 | pkt4_udp->len = htons ((uint16_t) payload_length); | ||
812 | GNUNET_TUN_calculate_udp4_checksum (pkt4, | ||
813 | pkt4_udp, | ||
814 | payload, | ||
815 | payload_length); | ||
816 | GNUNET_memcpy (&pkt4_udp[1], | ||
817 | payload, | ||
818 | payload_length); | ||
819 | } | ||
820 | break; | ||
821 | |||
822 | case IPPROTO_TCP: | ||
823 | { | ||
824 | struct GNUNET_TUN_TcpHeader *pkt4_tcp = (struct | ||
825 | GNUNET_TUN_TcpHeader *) &pkt4[1]; | ||
826 | |||
827 | *pkt4_tcp = *tcp_header; | ||
828 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
829 | "Sending TCP packet from port %u to port %u\n", | ||
830 | src_address->port, | ||
831 | dst_address->port); | ||
832 | pkt4_tcp->source_port = htons (src_address->port); | ||
833 | pkt4_tcp->destination_port = htons (dst_address->port); | ||
834 | GNUNET_TUN_calculate_tcp4_checksum (pkt4, | ||
835 | pkt4_tcp, | ||
836 | payload, | ||
837 | payload_length); | ||
838 | GNUNET_memcpy (&pkt4_tcp[1], | ||
839 | payload, | ||
840 | payload_length); | ||
841 | } | ||
842 | break; | ||
843 | |||
844 | default: | ||
845 | GNUNET_assert (0); | ||
846 | } | ||
847 | } | ||
848 | |||
849 | |||
850 | /** | ||
851 | * Prepare an IPv6 packet for transmission via the TUN interface. | ||
852 | * Initializes the IP header and calculates checksums (IP+UDP/TCP). | ||
853 | * For UDP, the UDP header will be fully created, whereas for TCP | ||
854 | * only the ports and checksum will be filled in. So for TCP, | ||
855 | * a skeleton TCP header must be part of the provided payload. | ||
856 | * | ||
857 | * @param payload payload of the packet (starting with UDP payload or | ||
858 | * TCP header, depending on protocol) | ||
859 | * @param payload_length number of bytes in @a payload | ||
860 | * @param protocol IPPROTO_UDP or IPPROTO_TCP | ||
861 | * @param tcp_header skeleton TCP header data to send, NULL for UDP | ||
862 | * @param src_address source address to use (IP and port) | ||
863 | * @param dst_address destination address to use (IP and port) | ||
864 | * @param pkt6 where to write the assembled packet; must | ||
865 | * contain enough space for the IP header, UDP/TCP header | ||
866 | * AND the payload | ||
867 | */ | ||
868 | static void | ||
869 | prepare_ipv6_packet (const void *payload, | ||
870 | size_t payload_length, | ||
871 | int protocol, | ||
872 | const struct GNUNET_TUN_TcpHeader *tcp_header, | ||
873 | const struct SocketAddress *src_address, | ||
874 | const struct SocketAddress *dst_address, | ||
875 | struct GNUNET_TUN_IPv6Header *pkt6) | ||
876 | { | ||
877 | size_t len; | ||
878 | |||
879 | len = payload_length; | ||
880 | switch (protocol) | ||
881 | { | ||
882 | case IPPROTO_UDP: | ||
883 | len += sizeof(struct GNUNET_TUN_UdpHeader); | ||
884 | break; | ||
885 | |||
886 | case IPPROTO_TCP: | ||
887 | len += sizeof(struct GNUNET_TUN_TcpHeader); | ||
888 | break; | ||
889 | |||
890 | default: | ||
891 | GNUNET_break (0); | ||
892 | return; | ||
893 | } | ||
894 | if (len > UINT16_MAX) | ||
895 | { | ||
896 | GNUNET_break (0); | ||
897 | return; | ||
898 | } | ||
899 | |||
900 | GNUNET_TUN_initialize_ipv6_header (pkt6, | ||
901 | protocol, | ||
902 | len, | ||
903 | &src_address->address.ipv6, | ||
904 | &dst_address->address.ipv6); | ||
905 | |||
906 | switch (protocol) | ||
907 | { | ||
908 | case IPPROTO_UDP: | ||
909 | { | ||
910 | struct GNUNET_TUN_UdpHeader *pkt6_udp = (struct | ||
911 | GNUNET_TUN_UdpHeader *) &pkt6[1]; | ||
912 | |||
913 | pkt6_udp->source_port = htons (src_address->port); | ||
914 | pkt6_udp->destination_port = htons (dst_address->port); | ||
915 | pkt6_udp->len = htons ((uint16_t) payload_length); | ||
916 | GNUNET_TUN_calculate_udp6_checksum (pkt6, | ||
917 | pkt6_udp, | ||
918 | payload, | ||
919 | payload_length); | ||
920 | GNUNET_memcpy (&pkt6_udp[1], | ||
921 | payload, | ||
922 | payload_length); | ||
923 | } | ||
924 | break; | ||
925 | |||
926 | case IPPROTO_TCP: | ||
927 | { | ||
928 | struct GNUNET_TUN_TcpHeader *pkt6_tcp = (struct | ||
929 | GNUNET_TUN_TcpHeader *) &pkt6[1]; | ||
930 | |||
931 | /* GNUNET_memcpy first here as some TCP header fields are initialized this way! */ | ||
932 | *pkt6_tcp = *tcp_header; | ||
933 | pkt6_tcp->source_port = htons (src_address->port); | ||
934 | pkt6_tcp->destination_port = htons (dst_address->port); | ||
935 | GNUNET_TUN_calculate_tcp6_checksum (pkt6, | ||
936 | pkt6_tcp, | ||
937 | payload, | ||
938 | payload_length); | ||
939 | GNUNET_memcpy (&pkt6_tcp[1], | ||
940 | payload, | ||
941 | payload_length); | ||
942 | } | ||
943 | break; | ||
944 | |||
945 | default: | ||
946 | GNUNET_assert (0); | ||
947 | break; | ||
948 | } | ||
949 | } | ||
950 | |||
951 | |||
952 | /** | ||
953 | * Send a TCP packet via the TUN interface. | ||
954 | * | ||
955 | * @param destination_address IP and port to use for the TCP packet's destination | ||
956 | * @param source_address IP and port to use for the TCP packet's source | ||
957 | * @param tcp_header header template to use | ||
958 | * @param payload payload of the TCP packet | ||
959 | * @param payload_length number of bytes in @a payload | ||
960 | */ | ||
961 | static void | ||
962 | send_tcp_packet_via_tun (const struct SocketAddress *destination_address, | ||
963 | const struct SocketAddress *source_address, | ||
964 | const struct GNUNET_TUN_TcpHeader *tcp_header, | ||
965 | const void *payload, | ||
966 | size_t payload_length) | ||
967 | { | ||
968 | size_t len; | ||
969 | |||
970 | GNUNET_STATISTICS_update (stats, | ||
971 | gettext_noop ("# TCP packets sent via TUN"), | ||
972 | 1, | ||
973 | GNUNET_NO); | ||
974 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
975 | "Sending packet with %u bytes TCP payload via TUN\n", | ||
976 | (unsigned int) payload_length); | ||
977 | len = sizeof(struct GNUNET_MessageHeader) + sizeof(struct | ||
978 | GNUNET_TUN_Layer2PacketHeader); | ||
979 | switch (source_address->af) | ||
980 | { | ||
981 | case AF_INET: | ||
982 | len += sizeof(struct GNUNET_TUN_IPv4Header); | ||
983 | break; | ||
984 | |||
985 | case AF_INET6: | ||
986 | len += sizeof(struct GNUNET_TUN_IPv6Header); | ||
987 | break; | ||
988 | |||
989 | default: | ||
990 | GNUNET_break (0); | ||
991 | return; | ||
992 | } | ||
993 | len += sizeof(struct GNUNET_TUN_TcpHeader); | ||
994 | len += payload_length; | ||
995 | if (len >= GNUNET_MAX_MESSAGE_SIZE) | ||
996 | { | ||
997 | GNUNET_break (0); | ||
998 | return; | ||
999 | } | ||
1000 | { | ||
1001 | char buf[len] GNUNET_ALIGN; | ||
1002 | struct GNUNET_MessageHeader *hdr; | ||
1003 | struct GNUNET_TUN_Layer2PacketHeader *tun; | ||
1004 | |||
1005 | hdr = (struct GNUNET_MessageHeader *) buf; | ||
1006 | hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER); | ||
1007 | hdr->size = htons (len); | ||
1008 | tun = (struct GNUNET_TUN_Layer2PacketHeader*) &hdr[1]; | ||
1009 | tun->flags = htons (0); | ||
1010 | switch (source_address->af) | ||
1011 | { | ||
1012 | case AF_INET: | ||
1013 | { | ||
1014 | struct GNUNET_TUN_IPv4Header *ipv4 | ||
1015 | = (struct GNUNET_TUN_IPv4Header*) &tun[1]; | ||
1016 | |||
1017 | tun->proto = htons (ETH_P_IPV4); | ||
1018 | prepare_ipv4_packet (payload, | ||
1019 | payload_length, | ||
1020 | IPPROTO_TCP, | ||
1021 | tcp_header, | ||
1022 | source_address, | ||
1023 | destination_address, | ||
1024 | ipv4); | ||
1025 | } | ||
1026 | break; | ||
1027 | |||
1028 | case AF_INET6: | ||
1029 | { | ||
1030 | struct GNUNET_TUN_IPv6Header *ipv6 | ||
1031 | = (struct GNUNET_TUN_IPv6Header*) &tun[1]; | ||
1032 | |||
1033 | tun->proto = htons (ETH_P_IPV6); | ||
1034 | prepare_ipv6_packet (payload, | ||
1035 | payload_length, | ||
1036 | IPPROTO_TCP, | ||
1037 | tcp_header, | ||
1038 | source_address, | ||
1039 | destination_address, | ||
1040 | ipv6); | ||
1041 | } | ||
1042 | break; | ||
1043 | |||
1044 | default: | ||
1045 | GNUNET_assert (0); | ||
1046 | break; | ||
1047 | } | ||
1048 | if (NULL != helper_handle) | ||
1049 | (void) GNUNET_HELPER_send (helper_handle, | ||
1050 | (const struct GNUNET_MessageHeader*) buf, | ||
1051 | GNUNET_YES, | ||
1052 | NULL, | ||
1053 | NULL); | ||
1054 | } | ||
1055 | } | ||
1056 | |||
1057 | |||
1058 | /** | ||
1059 | * Send an ICMP packet via the TUN interface. | ||
1060 | * | ||
1061 | * @param destination_address IP to use for the ICMP packet's destination | ||
1062 | * @param source_address IP to use for the ICMP packet's source | ||
1063 | * @param icmp_header ICMP header to send | ||
1064 | * @param payload payload of the ICMP packet (does NOT include ICMP header) | ||
1065 | * @param payload_length number of bytes of data in @a payload | ||
1066 | */ | ||
1067 | static void | ||
1068 | send_icmp_packet_via_tun (const struct SocketAddress *destination_address, | ||
1069 | const struct SocketAddress *source_address, | ||
1070 | const struct GNUNET_TUN_IcmpHeader *icmp_header, | ||
1071 | const void *payload, size_t payload_length) | ||
1072 | { | ||
1073 | size_t len; | ||
1074 | struct GNUNET_TUN_IcmpHeader *icmp; | ||
1075 | |||
1076 | GNUNET_STATISTICS_update (stats, | ||
1077 | gettext_noop ("# ICMP packets sent via TUN"), | ||
1078 | 1, GNUNET_NO); | ||
1079 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
1080 | "Sending packet with %u bytes ICMP payload via TUN\n", | ||
1081 | (unsigned int) payload_length); | ||
1082 | len = sizeof(struct GNUNET_MessageHeader) + sizeof(struct | ||
1083 | GNUNET_TUN_Layer2PacketHeader); | ||
1084 | switch (destination_address->af) | ||
1085 | { | ||
1086 | case AF_INET: | ||
1087 | len += sizeof(struct GNUNET_TUN_IPv4Header); | ||
1088 | break; | ||
1089 | |||
1090 | case AF_INET6: | ||
1091 | len += sizeof(struct GNUNET_TUN_IPv6Header); | ||
1092 | break; | ||
1093 | |||
1094 | default: | ||
1095 | GNUNET_break (0); | ||
1096 | return; | ||
1097 | } | ||
1098 | len += sizeof(struct GNUNET_TUN_IcmpHeader); | ||
1099 | len += payload_length; | ||
1100 | if (len >= GNUNET_MAX_MESSAGE_SIZE) | ||
1101 | { | ||
1102 | GNUNET_break (0); | ||
1103 | return; | ||
1104 | } | ||
1105 | { | ||
1106 | char buf[len] GNUNET_ALIGN; | ||
1107 | struct GNUNET_MessageHeader *hdr; | ||
1108 | struct GNUNET_TUN_Layer2PacketHeader *tun; | ||
1109 | |||
1110 | hdr = (struct GNUNET_MessageHeader *) buf; | ||
1111 | hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER); | ||
1112 | hdr->size = htons (len); | ||
1113 | tun = (struct GNUNET_TUN_Layer2PacketHeader*) &hdr[1]; | ||
1114 | tun->flags = htons (0); | ||
1115 | switch (source_address->af) | ||
1116 | { | ||
1117 | case AF_INET: | ||
1118 | { | ||
1119 | struct GNUNET_TUN_IPv4Header *ipv4 = (struct | ||
1120 | GNUNET_TUN_IPv4Header*) &tun[1]; | ||
1121 | |||
1122 | tun->proto = htons (ETH_P_IPV4); | ||
1123 | GNUNET_TUN_initialize_ipv4_header (ipv4, | ||
1124 | IPPROTO_ICMP, | ||
1125 | sizeof(struct | ||
1126 | GNUNET_TUN_IcmpHeader) | ||
1127 | + payload_length, | ||
1128 | &source_address->address.ipv4, | ||
1129 | &destination_address->address.ipv4); | ||
1130 | icmp = (struct GNUNET_TUN_IcmpHeader*) &ipv4[1]; | ||
1131 | } | ||
1132 | break; | ||
1133 | |||
1134 | case AF_INET6: | ||
1135 | { | ||
1136 | struct GNUNET_TUN_IPv6Header *ipv6 = (struct | ||
1137 | GNUNET_TUN_IPv6Header*) &tun[1]; | ||
1138 | |||
1139 | tun->proto = htons (ETH_P_IPV6); | ||
1140 | GNUNET_TUN_initialize_ipv6_header (ipv6, | ||
1141 | IPPROTO_ICMPV6, | ||
1142 | sizeof(struct | ||
1143 | GNUNET_TUN_IcmpHeader) | ||
1144 | + payload_length, | ||
1145 | &source_address->address.ipv6, | ||
1146 | &destination_address->address.ipv6); | ||
1147 | icmp = (struct GNUNET_TUN_IcmpHeader*) &ipv6[1]; | ||
1148 | } | ||
1149 | break; | ||
1150 | |||
1151 | default: | ||
1152 | GNUNET_assert (0); | ||
1153 | break; | ||
1154 | } | ||
1155 | *icmp = *icmp_header; | ||
1156 | GNUNET_memcpy (&icmp[1], | ||
1157 | payload, | ||
1158 | payload_length); | ||
1159 | GNUNET_TUN_calculate_icmp_checksum (icmp, | ||
1160 | payload, | ||
1161 | payload_length); | ||
1162 | if (NULL != helper_handle) | ||
1163 | (void) GNUNET_HELPER_send (helper_handle, | ||
1164 | (const struct GNUNET_MessageHeader*) buf, | ||
1165 | GNUNET_YES, | ||
1166 | NULL, NULL); | ||
1167 | } | ||
1168 | } | ||
1169 | |||
1170 | |||
1171 | /** | ||
1172 | * We need to create a (unique) fresh local address (IP+port). | ||
1173 | * Fill one in. | ||
1174 | * | ||
1175 | * @param af desired address family | ||
1176 | * @param proto desired protocol (IPPROTO_UDP or IPPROTO_TCP) | ||
1177 | * @param local_address address to initialize | ||
1178 | */ | ||
1179 | static void | ||
1180 | setup_fresh_address (int af, | ||
1181 | uint8_t proto, | ||
1182 | struct SocketAddress *local_address) | ||
1183 | { | ||
1184 | local_address->af = af; | ||
1185 | local_address->proto = (uint8_t) proto; | ||
1186 | /* default "local" port range is often 32768--61000, | ||
1187 | so we pick a random value in that range */ | ||
1188 | if (((af == AF_INET) && (proto == IPPROTO_ICMP)) || | ||
1189 | ((af == AF_INET6) && (proto == IPPROTO_ICMPV6))) | ||
1190 | local_address->port = 0; | ||
1191 | else | ||
1192 | local_address->port | ||
1193 | = (uint16_t) 32768 + GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, | ||
1194 | 28232); | ||
1195 | switch (af) | ||
1196 | { | ||
1197 | case AF_INET: | ||
1198 | { | ||
1199 | struct in_addr addr; | ||
1200 | struct in_addr mask; | ||
1201 | struct in_addr rnd; | ||
1202 | |||
1203 | addr = exit_ipv4addr; | ||
1204 | mask = exit_ipv4mask; | ||
1205 | if (0 == ~mask.s_addr) | ||
1206 | { | ||
1207 | /* only one valid IP anyway */ | ||
1208 | local_address->address.ipv4 = addr; | ||
1209 | return; | ||
1210 | } | ||
1211 | /* Given 192.168.0.1/255.255.0.0, we want a mask | ||
1212 | of '192.168.255.255', thus: */ | ||
1213 | mask.s_addr = addr.s_addr | ~mask.s_addr; | ||
1214 | /* Pick random IPv4 address within the subnet, except 'addr' or 'mask' itself */ | ||
1215 | do | ||
1216 | { | ||
1217 | rnd.s_addr = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, | ||
1218 | UINT32_MAX); | ||
1219 | local_address->address.ipv4.s_addr = (addr.s_addr | rnd.s_addr) | ||
1220 | & mask.s_addr; | ||
1221 | } | ||
1222 | while ((local_address->address.ipv4.s_addr == addr.s_addr) || | ||
1223 | (local_address->address.ipv4.s_addr == mask.s_addr)); | ||
1224 | } | ||
1225 | break; | ||
1226 | |||
1227 | case AF_INET6: | ||
1228 | { | ||
1229 | struct in6_addr addr; | ||
1230 | struct in6_addr mask; | ||
1231 | struct in6_addr rnd; | ||
1232 | int i; | ||
1233 | |||
1234 | addr = exit_ipv6addr; | ||
1235 | GNUNET_assert (ipv6prefix < 128); | ||
1236 | if (ipv6prefix == 127) | ||
1237 | { | ||
1238 | /* only one valid IP anyway */ | ||
1239 | local_address->address.ipv6 = addr; | ||
1240 | return; | ||
1241 | } | ||
1242 | /* Given ABCD::/96, we want a mask of 'ABCD::FFFF:FFFF, | ||
1243 | thus: */ | ||
1244 | mask = addr; | ||
1245 | for (i = 127; i >= ipv6prefix; i--) | ||
1246 | mask.s6_addr[i / 8] |= (1 << (i % 8)); | ||
1247 | |||
1248 | /* Pick random IPv6 address within the subnet, except 'addr' or 'mask' itself */ | ||
1249 | do | ||
1250 | { | ||
1251 | for (i = 0; i < 16; i++) | ||
1252 | { | ||
1253 | rnd.s6_addr[i] = (unsigned char) GNUNET_CRYPTO_random_u32 ( | ||
1254 | GNUNET_CRYPTO_QUALITY_WEAK, | ||
1255 | 256); | ||
1256 | local_address->address.ipv6.s6_addr[i] | ||
1257 | = (addr.s6_addr[i] | rnd.s6_addr[i]) & mask.s6_addr[i]; | ||
1258 | } | ||
1259 | } | ||
1260 | while ((0 == GNUNET_memcmp (&local_address->address.ipv6, | ||
1261 | &addr)) || | ||
1262 | (0 == GNUNET_memcmp (&local_address->address.ipv6, | ||
1263 | &mask))); | ||
1264 | } | ||
1265 | break; | ||
1266 | |||
1267 | default: | ||
1268 | GNUNET_assert (0); | ||
1269 | } | ||
1270 | } | ||
1271 | |||
1272 | |||
1273 | /** | ||
1274 | * We are starting a fresh connection (TCP or UDP) and need | ||
1275 | * to pick a source port and IP address (within the correct | ||
1276 | * range and address family) to associate replies with the | ||
1277 | * connection / correct cadet channel. This function generates | ||
1278 | * a "fresh" source IP and source port number for a connection | ||
1279 | * After picking a good source address, this function sets up | ||
1280 | * the state in the 'connections_map' and 'connections_heap' | ||
1281 | * to allow finding the state when needed later. The function | ||
1282 | * also makes sure that we remain within memory limits by | ||
1283 | * cleaning up 'old' states. | ||
1284 | * | ||
1285 | * @param state skeleton state to setup a record for; should | ||
1286 | * 'state->specifics.tcp_udp.ri.remote_address' filled in so that | ||
1287 | * this code can determine which AF/protocol is | ||
1288 | * going to be used (the 'channel' should also | ||
1289 | * already be set); after calling this function, | ||
1290 | * heap_node and the local_address will be | ||
1291 | * also initialized (heap_node != NULL can be | ||
1292 | * used to test if a state has been fully setup). | ||
1293 | */ | ||
1294 | static void | ||
1295 | setup_state_record (struct ChannelState *state) | ||
1296 | { | ||
1297 | struct GNUNET_HashCode key; | ||
1298 | struct ChannelState *s; | ||
1299 | |||
1300 | /* generate fresh, unique address */ | ||
1301 | do | ||
1302 | { | ||
1303 | if (NULL == state->specifics.tcp_udp.serv) | ||
1304 | setup_fresh_address (state->specifics.tcp_udp.ri.remote_address.af, | ||
1305 | state->specifics.tcp_udp.ri.remote_address.proto, | ||
1306 | &state->specifics.tcp_udp.ri.local_address); | ||
1307 | else | ||
1308 | setup_fresh_address (state->specifics.tcp_udp.serv->address.af, | ||
1309 | state->specifics.tcp_udp.serv->address.proto, | ||
1310 | &state->specifics.tcp_udp.ri.local_address); | ||
1311 | } | ||
1312 | while (NULL != | ||
1313 | get_redirect_state (state->specifics.tcp_udp.ri.remote_address.af, | ||
1314 | state->specifics.tcp_udp.ri.remote_address.proto, | ||
1315 | &state->specifics.tcp_udp.ri.remote_address.address, | ||
1316 | state->specifics.tcp_udp.ri.remote_address.port, | ||
1317 | &state->specifics.tcp_udp.ri.local_address.address, | ||
1318 | state->specifics.tcp_udp.ri.local_address.port, | ||
1319 | &key)); | ||
1320 | { | ||
1321 | char buf[INET6_ADDRSTRLEN]; | ||
1322 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
1323 | "Picked local address %s:%u for new connection\n", | ||
1324 | inet_ntop (state->specifics.tcp_udp.ri.local_address.af, | ||
1325 | &state->specifics.tcp_udp.ri.local_address.address, | ||
1326 | buf, | ||
1327 | sizeof(buf)), | ||
1328 | (unsigned int) state->specifics.tcp_udp.ri.local_address.port); | ||
1329 | } | ||
1330 | state->specifics.tcp_udp.state_key = key; | ||
1331 | GNUNET_assert (GNUNET_OK == | ||
1332 | GNUNET_CONTAINER_multihashmap_put (connections_map, | ||
1333 | &key, state, | ||
1334 | GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)); | ||
1335 | state->specifics.tcp_udp.heap_node | ||
1336 | = GNUNET_CONTAINER_heap_insert (connections_heap, | ||
1337 | state, | ||
1338 | GNUNET_TIME_absolute_get ().abs_value_us); | ||
1339 | while (GNUNET_CONTAINER_heap_get_size (connections_heap) > max_connections) | ||
1340 | { | ||
1341 | s = GNUNET_CONTAINER_heap_remove_root (connections_heap); | ||
1342 | GNUNET_assert (state != s); | ||
1343 | s->specifics.tcp_udp.heap_node = NULL; | ||
1344 | GNUNET_CADET_channel_destroy (s->channel); | ||
1345 | GNUNET_assert (GNUNET_OK == | ||
1346 | GNUNET_CONTAINER_multihashmap_remove (connections_map, | ||
1347 | &s->specifics.tcp_udp. | ||
1348 | state_key, | ||
1349 | s)); | ||
1350 | GNUNET_free (s); | ||
1351 | } | ||
1352 | } | ||
1353 | |||
1354 | |||
1355 | /** | ||
1356 | * Send a UDP packet via the TUN interface. | ||
1357 | * | ||
1358 | * @param destination_address IP and port to use for the UDP packet's destination | ||
1359 | * @param source_address IP and port to use for the UDP packet's source | ||
1360 | * @param payload payload of the UDP packet (does NOT include UDP header) | ||
1361 | * @param payload_length number of bytes of data in @a payload | ||
1362 | */ | ||
1363 | static void | ||
1364 | send_udp_packet_via_tun (const struct SocketAddress *destination_address, | ||
1365 | const struct SocketAddress *source_address, | ||
1366 | const void *payload, size_t payload_length) | ||
1367 | { | ||
1368 | size_t len; | ||
1369 | |||
1370 | GNUNET_STATISTICS_update (stats, | ||
1371 | gettext_noop ("# UDP packets sent via TUN"), | ||
1372 | 1, GNUNET_NO); | ||
1373 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
1374 | "Sending packet with %u bytes UDP payload via TUN\n", | ||
1375 | (unsigned int) payload_length); | ||
1376 | len = sizeof(struct GNUNET_MessageHeader) + sizeof(struct | ||
1377 | GNUNET_TUN_Layer2PacketHeader); | ||
1378 | switch (source_address->af) | ||
1379 | { | ||
1380 | case AF_INET: | ||
1381 | len += sizeof(struct GNUNET_TUN_IPv4Header); | ||
1382 | break; | ||
1383 | |||
1384 | case AF_INET6: | ||
1385 | len += sizeof(struct GNUNET_TUN_IPv6Header); | ||
1386 | break; | ||
1387 | |||
1388 | default: | ||
1389 | GNUNET_break (0); | ||
1390 | return; | ||
1391 | } | ||
1392 | len += sizeof(struct GNUNET_TUN_UdpHeader); | ||
1393 | len += payload_length; | ||
1394 | if (len >= GNUNET_MAX_MESSAGE_SIZE) | ||
1395 | { | ||
1396 | GNUNET_break (0); | ||
1397 | return; | ||
1398 | } | ||
1399 | { | ||
1400 | char buf[len] GNUNET_ALIGN; | ||
1401 | struct GNUNET_MessageHeader *hdr; | ||
1402 | struct GNUNET_TUN_Layer2PacketHeader *tun; | ||
1403 | |||
1404 | hdr = (struct GNUNET_MessageHeader *) buf; | ||
1405 | hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER); | ||
1406 | hdr->size = htons (len); | ||
1407 | tun = (struct GNUNET_TUN_Layer2PacketHeader*) &hdr[1]; | ||
1408 | tun->flags = htons (0); | ||
1409 | switch (source_address->af) | ||
1410 | { | ||
1411 | case AF_INET: | ||
1412 | { | ||
1413 | struct GNUNET_TUN_IPv4Header *ipv4 = (struct | ||
1414 | GNUNET_TUN_IPv4Header*) &tun[1]; | ||
1415 | |||
1416 | tun->proto = htons (ETH_P_IPV4); | ||
1417 | prepare_ipv4_packet (payload, | ||
1418 | payload_length, | ||
1419 | IPPROTO_UDP, | ||
1420 | NULL, | ||
1421 | source_address, | ||
1422 | destination_address, | ||
1423 | ipv4); | ||
1424 | } | ||
1425 | break; | ||
1426 | |||
1427 | case AF_INET6: | ||
1428 | { | ||
1429 | struct GNUNET_TUN_IPv6Header *ipv6 = (struct | ||
1430 | GNUNET_TUN_IPv6Header*) &tun[1]; | ||
1431 | |||
1432 | tun->proto = htons (ETH_P_IPV6); | ||
1433 | prepare_ipv6_packet (payload, | ||
1434 | payload_length, | ||
1435 | IPPROTO_UDP, | ||
1436 | NULL, | ||
1437 | source_address, | ||
1438 | destination_address, | ||
1439 | ipv6); | ||
1440 | } | ||
1441 | break; | ||
1442 | |||
1443 | default: | ||
1444 | GNUNET_assert (0); | ||
1445 | break; | ||
1446 | } | ||
1447 | if (NULL != helper_handle) | ||
1448 | (void) GNUNET_HELPER_send (helper_handle, | ||
1449 | (const struct GNUNET_MessageHeader*) buf, | ||
1450 | GNUNET_YES, | ||
1451 | NULL, NULL); | ||
1452 | } | ||
1453 | } | ||
1454 | |||
1455 | |||
1456 | /** | ||
1457 | * Check a request to forward UDP data to the Internet via this peer. | ||
1458 | * | ||
1459 | * @param cls our `struct ChannelState *` | ||
1460 | * @param msg the actual message | ||
1461 | * @return #GNUNET_OK to keep the connection open, | ||
1462 | * #GNUNET_SYSERR to close it (signal serious error) | ||
1463 | */ | ||
1464 | static int | ||
1465 | check_udp_remote (void *cls, | ||
1466 | const struct GNUNET_EXIT_UdpInternetMessage *msg) | ||
1467 | { | ||
1468 | struct ChannelState *state = cls; | ||
1469 | |||
1470 | if (GNUNET_YES == state->is_dns) | ||
1471 | { | ||
1472 | GNUNET_break_op (0); | ||
1473 | return GNUNET_SYSERR; | ||
1474 | } | ||
1475 | return GNUNET_OK; | ||
1476 | } | ||
1477 | |||
1478 | |||
1479 | /** | ||
1480 | * Process a request to forward UDP data to the Internet via this peer. | ||
1481 | * | ||
1482 | * @param cls our `struct ChannelState *` | ||
1483 | * @param msg the actual message | ||
1484 | */ | ||
1485 | static void | ||
1486 | handle_udp_remote (void *cls, | ||
1487 | const struct GNUNET_EXIT_UdpInternetMessage *msg) | ||
1488 | { | ||
1489 | struct ChannelState *state = cls; | ||
1490 | uint16_t pkt_len = ntohs (msg->header.size) - sizeof(struct | ||
1491 | GNUNET_EXIT_UdpInternetMessage); | ||
1492 | const struct in_addr *v4; | ||
1493 | const struct in6_addr *v6; | ||
1494 | const void *payload; | ||
1495 | int af; | ||
1496 | |||
1497 | if (GNUNET_SYSERR == state->is_dns) | ||
1498 | { | ||
1499 | /* channel is UDP/TCP from now on */ | ||
1500 | state->is_dns = GNUNET_NO; | ||
1501 | } | ||
1502 | GNUNET_STATISTICS_update (stats, | ||
1503 | gettext_noop ("# Bytes received from CADET"), | ||
1504 | pkt_len, GNUNET_NO); | ||
1505 | GNUNET_STATISTICS_update (stats, | ||
1506 | gettext_noop ( | ||
1507 | "# UDP IP-exit requests received via cadet"), | ||
1508 | 1, GNUNET_NO); | ||
1509 | af = (int) ntohl (msg->af); | ||
1510 | state->specifics.tcp_udp.ri.remote_address.af = af; | ||
1511 | switch (af) | ||
1512 | { | ||
1513 | case AF_INET: | ||
1514 | if (pkt_len < sizeof(struct in_addr)) | ||
1515 | { | ||
1516 | GNUNET_break_op (0); | ||
1517 | return; | ||
1518 | } | ||
1519 | if (! ipv4_exit) | ||
1520 | { | ||
1521 | GNUNET_break_op (0); | ||
1522 | return; | ||
1523 | } | ||
1524 | v4 = (const struct in_addr*) &msg[1]; | ||
1525 | payload = &v4[1]; | ||
1526 | pkt_len -= sizeof(struct in_addr); | ||
1527 | state->specifics.tcp_udp.ri.remote_address.address.ipv4 = *v4; | ||
1528 | break; | ||
1529 | |||
1530 | case AF_INET6: | ||
1531 | if (pkt_len < sizeof(struct in6_addr)) | ||
1532 | { | ||
1533 | GNUNET_break_op (0); | ||
1534 | return; | ||
1535 | } | ||
1536 | if (! ipv6_exit) | ||
1537 | { | ||
1538 | GNUNET_break_op (0); | ||
1539 | return; | ||
1540 | } | ||
1541 | v6 = (const struct in6_addr*) &msg[1]; | ||
1542 | payload = &v6[1]; | ||
1543 | pkt_len -= sizeof(struct in6_addr); | ||
1544 | state->specifics.tcp_udp.ri.remote_address.address.ipv6 = *v6; | ||
1545 | break; | ||
1546 | |||
1547 | default: | ||
1548 | GNUNET_break_op (0); | ||
1549 | return; | ||
1550 | } | ||
1551 | { | ||
1552 | char buf[INET6_ADDRSTRLEN]; | ||
1553 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
1554 | "Received data from %s for forwarding to UDP %s:%u\n", | ||
1555 | GNUNET_i2s (&state->peer), | ||
1556 | inet_ntop (af, | ||
1557 | &state->specifics.tcp_udp.ri.remote_address.address, | ||
1558 | buf, sizeof(buf)), | ||
1559 | (unsigned int) ntohs (msg->destination_port)); | ||
1560 | } | ||
1561 | state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_UDP; | ||
1562 | state->specifics.tcp_udp.ri.remote_address.port = msg->destination_port; | ||
1563 | if (NULL == state->specifics.tcp_udp.heap_node) | ||
1564 | setup_state_record (state); | ||
1565 | if (0 != ntohs (msg->source_port)) | ||
1566 | state->specifics.tcp_udp.ri.local_address.port = msg->source_port; | ||
1567 | send_udp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, | ||
1568 | &state->specifics.tcp_udp.ri.local_address, | ||
1569 | payload, | ||
1570 | pkt_len); | ||
1571 | GNUNET_CADET_receive_done (state->channel); | ||
1572 | } | ||
1573 | |||
1574 | |||
1575 | /** | ||
1576 | * Check a request via cadet to send a request to a UDP service | ||
1577 | * offered by this system. | ||
1578 | * | ||
1579 | * @param cls our `struct ChannelState *` | ||
1580 | * @param msg the actual message | ||
1581 | * @return #GNUNET_OK to keep the connection open, | ||
1582 | * #GNUNET_SYSERR to close it (signal serious error) | ||
1583 | */ | ||
1584 | static int | ||
1585 | check_udp_service (void *cls, | ||
1586 | const struct GNUNET_EXIT_UdpServiceMessage *msg) | ||
1587 | { | ||
1588 | struct ChannelState *state = cls; | ||
1589 | |||
1590 | if (NULL == state->specifics.tcp_udp.serv) | ||
1591 | { | ||
1592 | GNUNET_break_op (0); | ||
1593 | return GNUNET_SYSERR; | ||
1594 | } | ||
1595 | return GNUNET_OK; | ||
1596 | } | ||
1597 | |||
1598 | |||
1599 | /** | ||
1600 | * Process a request via cadet to send a request to a UDP service | ||
1601 | * offered by this system. | ||
1602 | * | ||
1603 | * @param cls our `struct ChannelState *` | ||
1604 | * @param msg the actual message | ||
1605 | */ | ||
1606 | static void | ||
1607 | handle_udp_service (void *cls, | ||
1608 | const struct GNUNET_EXIT_UdpServiceMessage *msg) | ||
1609 | { | ||
1610 | struct ChannelState *state = cls; | ||
1611 | uint16_t pkt_len = ntohs (msg->header.size) - sizeof(struct | ||
1612 | GNUNET_EXIT_UdpServiceMessage); | ||
1613 | |||
1614 | GNUNET_STATISTICS_update (stats, | ||
1615 | gettext_noop ("# Bytes received from CADET"), | ||
1616 | pkt_len, GNUNET_NO); | ||
1617 | GNUNET_STATISTICS_update (stats, | ||
1618 | gettext_noop ( | ||
1619 | "# UDP service requests received via cadet"), | ||
1620 | 1, GNUNET_NO); | ||
1621 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
1622 | "Received data from %s for forwarding to UDP service %s on port %u\n", | ||
1623 | GNUNET_i2s (&state->peer), | ||
1624 | GNUNET_h2s (&state->specifics.tcp_udp.serv->descriptor), | ||
1625 | (unsigned int) ntohs (msg->destination_port)); | ||
1626 | setup_state_record (state); | ||
1627 | if (0 != ntohs (msg->source_port)) | ||
1628 | state->specifics.tcp_udp.ri.local_address.port = msg->source_port; | ||
1629 | send_udp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, | ||
1630 | &state->specifics.tcp_udp.ri.local_address, | ||
1631 | &msg[1], | ||
1632 | pkt_len); | ||
1633 | GNUNET_CADET_receive_done (state->channel); | ||
1634 | } | ||
1635 | |||
1636 | |||
1637 | /** | ||
1638 | * Process a request via cadet to send a request to a TCP service | ||
1639 | * offered by this system. | ||
1640 | * | ||
1641 | * @param cls our `struct ChannelState *` | ||
1642 | * @param start the actual message | ||
1643 | * @return #GNUNET_OK to keep the connection open, | ||
1644 | * #GNUNET_SYSERR to close it (signal serious error) | ||
1645 | */ | ||
1646 | static void | ||
1647 | handle_tcp_service (void *cls, | ||
1648 | const struct GNUNET_EXIT_TcpServiceStartMessage *start) | ||
1649 | { | ||
1650 | struct ChannelState *state = cls; | ||
1651 | uint16_t pkt_len = ntohs (start->header.size) - sizeof(struct | ||
1652 | GNUNET_EXIT_TcpServiceStartMessage); | ||
1653 | |||
1654 | if (GNUNET_SYSERR == state->is_dns) | ||
1655 | { | ||
1656 | /* channel is UDP/TCP from now on */ | ||
1657 | state->is_dns = GNUNET_NO; | ||
1658 | } | ||
1659 | GNUNET_STATISTICS_update (stats, | ||
1660 | gettext_noop ( | ||
1661 | "# TCP service creation requests received via cadet"), | ||
1662 | 1, | ||
1663 | GNUNET_NO); | ||
1664 | GNUNET_STATISTICS_update (stats, | ||
1665 | gettext_noop ("# Bytes received from CADET"), | ||
1666 | pkt_len, | ||
1667 | GNUNET_NO); | ||
1668 | GNUNET_break_op (ntohl (start->reserved) == 0); | ||
1669 | /* setup fresh connection */ | ||
1670 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
1671 | "Received data from %s for forwarding to TCP service %s on port %u\n", | ||
1672 | GNUNET_i2s (&state->peer), | ||
1673 | GNUNET_h2s (&state->specifics.tcp_udp.serv->descriptor), | ||
1674 | (unsigned int) ntohs (start->tcp_header.destination_port)); | ||
1675 | setup_state_record (state); | ||
1676 | send_tcp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, | ||
1677 | &state->specifics.tcp_udp.ri.local_address, | ||
1678 | &start->tcp_header, | ||
1679 | &start[1], | ||
1680 | pkt_len); | ||
1681 | GNUNET_CADET_receive_done (state->channel); | ||
1682 | } | ||
1683 | |||
1684 | |||
1685 | /** | ||
1686 | * Check a request to forward TCP data to the Internet via this peer. | ||
1687 | * | ||
1688 | * @param cls our `struct ChannelState *` | ||
1689 | * @param start the actual message | ||
1690 | * @return #GNUNET_OK to keep the connection open, | ||
1691 | * #GNUNET_SYSERR to close it (signal serious error) | ||
1692 | */ | ||
1693 | static int | ||
1694 | check_tcp_remote (void *cls, | ||
1695 | const struct GNUNET_EXIT_TcpInternetStartMessage *start) | ||
1696 | { | ||
1697 | struct ChannelState *state = cls; | ||
1698 | |||
1699 | if (NULL == state) | ||
1700 | { | ||
1701 | GNUNET_break_op (0); | ||
1702 | return GNUNET_SYSERR; | ||
1703 | } | ||
1704 | if (GNUNET_YES == state->is_dns) | ||
1705 | { | ||
1706 | GNUNET_break_op (0); | ||
1707 | return GNUNET_SYSERR; | ||
1708 | } | ||
1709 | if ((NULL != state->specifics.tcp_udp.serv) || | ||
1710 | (NULL != state->specifics.tcp_udp.heap_node)) | ||
1711 | { | ||
1712 | GNUNET_break_op (0); | ||
1713 | return GNUNET_SYSERR; | ||
1714 | } | ||
1715 | if (start->tcp_header.off * 4 < sizeof(struct GNUNET_TUN_TcpHeader)) | ||
1716 | { | ||
1717 | GNUNET_break_op (0); | ||
1718 | return GNUNET_SYSERR; | ||
1719 | } | ||
1720 | return GNUNET_OK; | ||
1721 | } | ||
1722 | |||
1723 | |||
1724 | /** | ||
1725 | * Process a request to forward TCP data to the Internet via this peer. | ||
1726 | * | ||
1727 | * @param cls our `struct ChannelState *` | ||
1728 | * @param start the actual message | ||
1729 | */ | ||
1730 | static void | ||
1731 | handle_tcp_remote (void *cls, | ||
1732 | const struct GNUNET_EXIT_TcpInternetStartMessage *start) | ||
1733 | { | ||
1734 | struct ChannelState *state = cls; | ||
1735 | uint16_t pkt_len = ntohs (start->header.size) - sizeof(struct | ||
1736 | GNUNET_EXIT_TcpInternetStartMessage); | ||
1737 | const struct in_addr *v4; | ||
1738 | const struct in6_addr *v6; | ||
1739 | const void *payload; | ||
1740 | int af; | ||
1741 | |||
1742 | if (GNUNET_SYSERR == state->is_dns) | ||
1743 | { | ||
1744 | /* channel is UDP/TCP from now on */ | ||
1745 | state->is_dns = GNUNET_NO; | ||
1746 | } | ||
1747 | GNUNET_STATISTICS_update (stats, | ||
1748 | gettext_noop ("# Bytes received from CADET"), | ||
1749 | pkt_len, GNUNET_NO); | ||
1750 | GNUNET_STATISTICS_update (stats, | ||
1751 | gettext_noop ( | ||
1752 | "# TCP IP-exit creation requests received via cadet"), | ||
1753 | 1, GNUNET_NO); | ||
1754 | af = (int) ntohl (start->af); | ||
1755 | state->specifics.tcp_udp.ri.remote_address.af = af; | ||
1756 | switch (af) | ||
1757 | { | ||
1758 | case AF_INET: | ||
1759 | if (pkt_len < sizeof(struct in_addr)) | ||
1760 | { | ||
1761 | GNUNET_break_op (0); | ||
1762 | return; | ||
1763 | } | ||
1764 | if (! ipv4_exit) | ||
1765 | { | ||
1766 | GNUNET_break_op (0); | ||
1767 | return; | ||
1768 | } | ||
1769 | v4 = (const struct in_addr*) &start[1]; | ||
1770 | payload = &v4[1]; | ||
1771 | pkt_len -= sizeof(struct in_addr); | ||
1772 | state->specifics.tcp_udp.ri.remote_address.address.ipv4 = *v4; | ||
1773 | break; | ||
1774 | |||
1775 | case AF_INET6: | ||
1776 | if (pkt_len < sizeof(struct in6_addr)) | ||
1777 | { | ||
1778 | GNUNET_break_op (0); | ||
1779 | return; | ||
1780 | } | ||
1781 | if (! ipv6_exit) | ||
1782 | { | ||
1783 | GNUNET_break_op (0); | ||
1784 | return; | ||
1785 | } | ||
1786 | v6 = (const struct in6_addr*) &start[1]; | ||
1787 | payload = &v6[1]; | ||
1788 | pkt_len -= sizeof(struct in6_addr); | ||
1789 | state->specifics.tcp_udp.ri.remote_address.address.ipv6 = *v6; | ||
1790 | break; | ||
1791 | |||
1792 | default: | ||
1793 | GNUNET_break_op (0); | ||
1794 | return; | ||
1795 | } | ||
1796 | { | ||
1797 | char buf[INET6_ADDRSTRLEN]; | ||
1798 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
1799 | "Received payload from %s for existing TCP stream to %s:%u\n", | ||
1800 | GNUNET_i2s (&state->peer), | ||
1801 | inet_ntop (af, | ||
1802 | &state->specifics.tcp_udp.ri.remote_address.address, | ||
1803 | buf, sizeof(buf)), | ||
1804 | (unsigned int) ntohs (start->tcp_header.destination_port)); | ||
1805 | } | ||
1806 | state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_TCP; | ||
1807 | state->specifics.tcp_udp.ri.remote_address.port = ntohs ( | ||
1808 | start->tcp_header.destination_port); | ||
1809 | setup_state_record (state); | ||
1810 | send_tcp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, | ||
1811 | &state->specifics.tcp_udp.ri.local_address, | ||
1812 | &start->tcp_header, | ||
1813 | payload, | ||
1814 | pkt_len); | ||
1815 | GNUNET_CADET_receive_done (state->channel); | ||
1816 | } | ||
1817 | |||
1818 | |||
1819 | /** | ||
1820 | * Check a request to forward TCP data on an established | ||
1821 | * connection via this peer. | ||
1822 | * | ||
1823 | * @param cls our `struct ChannelState *` | ||
1824 | * @param message the actual message | ||
1825 | * @return #GNUNET_OK to keep the connection open, | ||
1826 | * #GNUNET_SYSERR to close it (signal serious error) | ||
1827 | */ | ||
1828 | static int | ||
1829 | check_tcp_data (void *cls, | ||
1830 | const struct GNUNET_EXIT_TcpDataMessage *data) | ||
1831 | { | ||
1832 | struct ChannelState *state = cls; | ||
1833 | |||
1834 | if ((NULL == state) || | ||
1835 | (NULL == state->specifics.tcp_udp.heap_node)) | ||
1836 | { | ||
1837 | /* connection should have been up! */ | ||
1838 | GNUNET_STATISTICS_update (stats, | ||
1839 | gettext_noop ( | ||
1840 | "# TCP DATA requests dropped (no session)"), | ||
1841 | 1, GNUNET_NO); | ||
1842 | GNUNET_break_op (0); | ||
1843 | return GNUNET_SYSERR; | ||
1844 | } | ||
1845 | if (data->tcp_header.off * 4 < sizeof(struct GNUNET_TUN_TcpHeader)) | ||
1846 | { | ||
1847 | GNUNET_break_op (0); | ||
1848 | return GNUNET_SYSERR; | ||
1849 | } | ||
1850 | if (GNUNET_YES == state->is_dns) | ||
1851 | { | ||
1852 | GNUNET_break_op (0); | ||
1853 | return GNUNET_SYSERR; | ||
1854 | } | ||
1855 | return GNUNET_OK; | ||
1856 | } | ||
1857 | |||
1858 | |||
1859 | /** | ||
1860 | * Process a request to forward TCP data on an established | ||
1861 | * connection via this peer. | ||
1862 | * | ||
1863 | * @param cls our `struct ChannelState *` | ||
1864 | * @param message the actual message | ||
1865 | */ | ||
1866 | static void | ||
1867 | handle_tcp_data (void *cls, | ||
1868 | const struct GNUNET_EXIT_TcpDataMessage *data) | ||
1869 | { | ||
1870 | struct ChannelState *state = cls; | ||
1871 | uint16_t pkt_len = ntohs (data->header.size) - sizeof(struct | ||
1872 | GNUNET_EXIT_TcpDataMessage); | ||
1873 | |||
1874 | GNUNET_STATISTICS_update (stats, | ||
1875 | gettext_noop ("# Bytes received from CADET"), | ||
1876 | pkt_len, GNUNET_NO); | ||
1877 | GNUNET_STATISTICS_update (stats, | ||
1878 | gettext_noop ( | ||
1879 | "# TCP data requests received via cadet"), | ||
1880 | 1, GNUNET_NO); | ||
1881 | if (GNUNET_SYSERR == state->is_dns) | ||
1882 | { | ||
1883 | /* channel is UDP/TCP from now on */ | ||
1884 | state->is_dns = GNUNET_NO; | ||
1885 | } | ||
1886 | |||
1887 | GNUNET_break_op (ntohl (data->reserved) == 0); | ||
1888 | { | ||
1889 | char buf[INET6_ADDRSTRLEN]; | ||
1890 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
1891 | "Received additional %u bytes of data from %s for TCP stream to %s:%u\n", | ||
1892 | pkt_len, | ||
1893 | GNUNET_i2s (&state->peer), | ||
1894 | inet_ntop (state->specifics.tcp_udp.ri.remote_address.af, | ||
1895 | &state->specifics.tcp_udp.ri.remote_address.address, | ||
1896 | buf, sizeof(buf)), | ||
1897 | (unsigned int) state->specifics.tcp_udp.ri.remote_address.port); | ||
1898 | } | ||
1899 | |||
1900 | send_tcp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, | ||
1901 | &state->specifics.tcp_udp.ri.local_address, | ||
1902 | &data->tcp_header, | ||
1903 | &data[1], pkt_len); | ||
1904 | GNUNET_CADET_receive_done (state->channel); | ||
1905 | } | ||
1906 | |||
1907 | |||
1908 | /** | ||
1909 | * Synthesize a plausible ICMP payload for an ICMPv4 error | ||
1910 | * response on the given channel. | ||
1911 | * | ||
1912 | * @param state channel information | ||
1913 | * @param ipp IPv6 header to fill in (ICMP payload) | ||
1914 | * @param udp "UDP" header to fill in (ICMP payload); might actually | ||
1915 | * also be the first 8 bytes of the TCP header | ||
1916 | */ | ||
1917 | static void | ||
1918 | make_up_icmpv4_payload (struct ChannelState *state, | ||
1919 | struct GNUNET_TUN_IPv4Header *ipp, | ||
1920 | struct GNUNET_TUN_UdpHeader *udp) | ||
1921 | { | ||
1922 | GNUNET_TUN_initialize_ipv4_header (ipp, | ||
1923 | state->specifics.tcp_udp.ri.remote_address. | ||
1924 | proto, | ||
1925 | sizeof(struct GNUNET_TUN_TcpHeader), | ||
1926 | &state->specifics.tcp_udp.ri.remote_address | ||
1927 | .address.ipv4, | ||
1928 | &state->specifics.tcp_udp.ri.local_address. | ||
1929 | address.ipv4); | ||
1930 | udp->source_port = htons (state->specifics.tcp_udp.ri.remote_address.port); | ||
1931 | udp->destination_port = htons ( | ||
1932 | state->specifics.tcp_udp.ri.local_address.port); | ||
1933 | udp->len = htons (0); | ||
1934 | udp->crc = htons (0); | ||
1935 | } | ||
1936 | |||
1937 | |||
1938 | /** | ||
1939 | * Synthesize a plausible ICMP payload for an ICMPv6 error | ||
1940 | * response on the given channel. | ||
1941 | * | ||
1942 | * @param state channel information | ||
1943 | * @param ipp IPv6 header to fill in (ICMP payload) | ||
1944 | * @param udp "UDP" header to fill in (ICMP payload); might actually | ||
1945 | * also be the first 8 bytes of the TCP header | ||
1946 | */ | ||
1947 | static void | ||
1948 | make_up_icmpv6_payload (struct ChannelState *state, | ||
1949 | struct GNUNET_TUN_IPv6Header *ipp, | ||
1950 | struct GNUNET_TUN_UdpHeader *udp) | ||
1951 | { | ||
1952 | GNUNET_TUN_initialize_ipv6_header (ipp, | ||
1953 | state->specifics.tcp_udp.ri.remote_address. | ||
1954 | proto, | ||
1955 | sizeof(struct GNUNET_TUN_TcpHeader), | ||
1956 | &state->specifics.tcp_udp.ri.remote_address | ||
1957 | .address.ipv6, | ||
1958 | &state->specifics.tcp_udp.ri.local_address. | ||
1959 | address.ipv6); | ||
1960 | udp->source_port = htons (state->specifics.tcp_udp.ri.remote_address.port); | ||
1961 | udp->destination_port = htons ( | ||
1962 | state->specifics.tcp_udp.ri.local_address.port); | ||
1963 | udp->len = htons (0); | ||
1964 | udp->crc = htons (0); | ||
1965 | } | ||
1966 | |||
1967 | |||
1968 | /** | ||
1969 | * Check a request to forward ICMP data to the Internet via this peer. | ||
1970 | * | ||
1971 | * @param cls our `struct ChannelState *` | ||
1972 | * @param msg the actual message | ||
1973 | * @return #GNUNET_OK to keep the connection open, | ||
1974 | * #GNUNET_SYSERR to close it (signal serious error) | ||
1975 | */ | ||
1976 | static int | ||
1977 | check_icmp_remote (void *cls, | ||
1978 | const struct GNUNET_EXIT_IcmpInternetMessage *msg) | ||
1979 | { | ||
1980 | struct ChannelState *state = cls; | ||
1981 | |||
1982 | if (GNUNET_YES == state->is_dns) | ||
1983 | { | ||
1984 | GNUNET_break_op (0); | ||
1985 | return GNUNET_SYSERR; | ||
1986 | } | ||
1987 | return GNUNET_OK; | ||
1988 | } | ||
1989 | |||
1990 | |||
1991 | /** | ||
1992 | * Process a request to forward ICMP data to the Internet via this peer. | ||
1993 | * | ||
1994 | * @param cls our `struct ChannelState *` | ||
1995 | * @param msg the actual message | ||
1996 | */ | ||
1997 | static void | ||
1998 | handle_icmp_remote (void *cls, | ||
1999 | const struct GNUNET_EXIT_IcmpInternetMessage *msg) | ||
2000 | { | ||
2001 | struct ChannelState *state = cls; | ||
2002 | uint16_t pkt_len = ntohs (msg->header.size) - sizeof(struct | ||
2003 | GNUNET_EXIT_IcmpInternetMessage); | ||
2004 | const struct in_addr *v4; | ||
2005 | const struct in6_addr *v6; | ||
2006 | const void *payload; | ||
2007 | char buf[sizeof(struct GNUNET_TUN_IPv6Header) + 8] GNUNET_ALIGN; | ||
2008 | int af; | ||
2009 | |||
2010 | if (GNUNET_SYSERR == state->is_dns) | ||
2011 | { | ||
2012 | /* channel is UDP/TCP from now on */ | ||
2013 | state->is_dns = GNUNET_NO; | ||
2014 | } | ||
2015 | GNUNET_STATISTICS_update (stats, | ||
2016 | gettext_noop ("# Bytes received from CADET"), | ||
2017 | pkt_len, GNUNET_NO); | ||
2018 | GNUNET_STATISTICS_update (stats, | ||
2019 | gettext_noop ( | ||
2020 | "# ICMP IP-exit requests received via cadet"), | ||
2021 | 1, GNUNET_NO); | ||
2022 | |||
2023 | af = (int) ntohl (msg->af); | ||
2024 | if ((NULL != state->specifics.tcp_udp.heap_node) && | ||
2025 | (af != state->specifics.tcp_udp.ri.remote_address.af)) | ||
2026 | { | ||
2027 | /* other peer switched AF on this channel; not allowed */ | ||
2028 | GNUNET_break_op (0); | ||
2029 | return; | ||
2030 | } | ||
2031 | |||
2032 | switch (af) | ||
2033 | { | ||
2034 | case AF_INET: | ||
2035 | if (pkt_len < sizeof(struct in_addr)) | ||
2036 | { | ||
2037 | GNUNET_break_op (0); | ||
2038 | return; | ||
2039 | } | ||
2040 | if (! ipv4_exit) | ||
2041 | { | ||
2042 | GNUNET_break_op (0); | ||
2043 | return; | ||
2044 | } | ||
2045 | v4 = (const struct in_addr*) &msg[1]; | ||
2046 | payload = &v4[1]; | ||
2047 | pkt_len -= sizeof(struct in_addr); | ||
2048 | state->specifics.tcp_udp.ri.remote_address.address.ipv4 = *v4; | ||
2049 | if (NULL == state->specifics.tcp_udp.heap_node) | ||
2050 | { | ||
2051 | state->specifics.tcp_udp.ri.remote_address.af = af; | ||
2052 | state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_ICMP; | ||
2053 | setup_state_record (state); | ||
2054 | } | ||
2055 | /* check that ICMP type is something we want to support | ||
2056 | and possibly make up payload! */ | ||
2057 | switch (msg->icmp_header.type) | ||
2058 | { | ||
2059 | case GNUNET_TUN_ICMPTYPE_ECHO_REPLY: | ||
2060 | case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST: | ||
2061 | break; | ||
2062 | |||
2063 | case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE: | ||
2064 | case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH: | ||
2065 | case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED: | ||
2066 | if (0 != pkt_len) | ||
2067 | { | ||
2068 | GNUNET_break_op (0); | ||
2069 | return; | ||
2070 | } | ||
2071 | /* make up payload */ | ||
2072 | { | ||
2073 | struct GNUNET_TUN_IPv4Header *ipp = (struct | ||
2074 | GNUNET_TUN_IPv4Header *) buf; | ||
2075 | struct GNUNET_TUN_UdpHeader *udp = (struct | ||
2076 | GNUNET_TUN_UdpHeader *) &ipp[1]; | ||
2077 | |||
2078 | GNUNET_assert (8 == sizeof(struct GNUNET_TUN_UdpHeader)); | ||
2079 | pkt_len = sizeof(struct GNUNET_TUN_IPv4Header) + 8; | ||
2080 | make_up_icmpv4_payload (state, | ||
2081 | ipp, | ||
2082 | udp); | ||
2083 | payload = ipp; | ||
2084 | } | ||
2085 | break; | ||
2086 | |||
2087 | default: | ||
2088 | GNUNET_break_op (0); | ||
2089 | GNUNET_STATISTICS_update (stats, | ||
2090 | gettext_noop ( | ||
2091 | "# ICMPv4 packets dropped (type not allowed)"), | ||
2092 | 1, GNUNET_NO); | ||
2093 | return; | ||
2094 | } | ||
2095 | /* end AF_INET */ | ||
2096 | break; | ||
2097 | |||
2098 | case AF_INET6: | ||
2099 | if (pkt_len < sizeof(struct in6_addr)) | ||
2100 | { | ||
2101 | GNUNET_break_op (0); | ||
2102 | return; | ||
2103 | } | ||
2104 | if (! ipv6_exit) | ||
2105 | { | ||
2106 | GNUNET_break_op (0); | ||
2107 | return; | ||
2108 | } | ||
2109 | v6 = (const struct in6_addr*) &msg[1]; | ||
2110 | payload = &v6[1]; | ||
2111 | pkt_len -= sizeof(struct in6_addr); | ||
2112 | state->specifics.tcp_udp.ri.remote_address.address.ipv6 = *v6; | ||
2113 | if (NULL == state->specifics.tcp_udp.heap_node) | ||
2114 | { | ||
2115 | state->specifics.tcp_udp.ri.remote_address.af = af; | ||
2116 | state->specifics.tcp_udp.ri.remote_address.proto = IPPROTO_ICMPV6; | ||
2117 | setup_state_record (state); | ||
2118 | } | ||
2119 | /* check that ICMP type is something we want to support | ||
2120 | and possibly make up payload! */ | ||
2121 | switch (msg->icmp_header.type) | ||
2122 | { | ||
2123 | case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY: | ||
2124 | case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST: | ||
2125 | break; | ||
2126 | |||
2127 | case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE: | ||
2128 | case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG: | ||
2129 | case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED: | ||
2130 | case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM: | ||
2131 | if (0 != pkt_len) | ||
2132 | { | ||
2133 | GNUNET_break_op (0); | ||
2134 | return; | ||
2135 | } | ||
2136 | /* make up payload */ | ||
2137 | { | ||
2138 | struct GNUNET_TUN_IPv6Header *ipp = (struct | ||
2139 | GNUNET_TUN_IPv6Header *) buf; | ||
2140 | struct GNUNET_TUN_UdpHeader *udp = (struct | ||
2141 | GNUNET_TUN_UdpHeader *) &ipp[1]; | ||
2142 | |||
2143 | GNUNET_assert (8 == sizeof(struct GNUNET_TUN_UdpHeader)); | ||
2144 | pkt_len = sizeof(struct GNUNET_TUN_IPv6Header) + 8; | ||
2145 | make_up_icmpv6_payload (state, | ||
2146 | ipp, | ||
2147 | udp); | ||
2148 | payload = ipp; | ||
2149 | } | ||
2150 | break; | ||
2151 | |||
2152 | default: | ||
2153 | GNUNET_break_op (0); | ||
2154 | GNUNET_STATISTICS_update (stats, | ||
2155 | gettext_noop ( | ||
2156 | "# ICMPv6 packets dropped (type not allowed)"), | ||
2157 | 1, GNUNET_NO); | ||
2158 | return; | ||
2159 | } | ||
2160 | /* end AF_INET6 */ | ||
2161 | break; | ||
2162 | |||
2163 | default: | ||
2164 | /* bad AF */ | ||
2165 | GNUNET_break_op (0); | ||
2166 | return; | ||
2167 | } | ||
2168 | |||
2169 | { | ||
2170 | char buf[INET6_ADDRSTRLEN]; | ||
2171 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
2172 | "Received ICMP data from %s for forwarding to %s\n", | ||
2173 | GNUNET_i2s (&state->peer), | ||
2174 | inet_ntop (af, | ||
2175 | &state->specifics.tcp_udp.ri.remote_address.address, | ||
2176 | buf, sizeof(buf))); | ||
2177 | } | ||
2178 | send_icmp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, | ||
2179 | &state->specifics.tcp_udp.ri.local_address, | ||
2180 | &msg->icmp_header, | ||
2181 | payload, pkt_len); | ||
2182 | GNUNET_CADET_receive_done (state->channel); | ||
2183 | } | ||
2184 | |||
2185 | |||
2186 | /** | ||
2187 | * Setup ICMP payload for ICMP error messages. Called | ||
2188 | * for both IPv4 and IPv6 addresses. | ||
2189 | * | ||
2190 | * @param state context for creating the IP Packet | ||
2191 | * @param buf where to create the payload, has at least | ||
2192 | * sizeof (struct GNUNET_TUN_IPv6Header) + 8 bytes | ||
2193 | * @return number of bytes of payload we created in buf | ||
2194 | */ | ||
2195 | static uint16_t | ||
2196 | make_up_icmp_service_payload (struct ChannelState *state, | ||
2197 | char *buf) | ||
2198 | { | ||
2199 | switch (state->specifics.tcp_udp.serv->address.af) | ||
2200 | { | ||
2201 | case AF_INET: | ||
2202 | { | ||
2203 | struct GNUNET_TUN_IPv4Header *ipv4; | ||
2204 | struct GNUNET_TUN_UdpHeader *udp; | ||
2205 | |||
2206 | ipv4 = (struct GNUNET_TUN_IPv4Header *) buf; | ||
2207 | udp = (struct GNUNET_TUN_UdpHeader *) &ipv4[1]; | ||
2208 | make_up_icmpv4_payload (state, | ||
2209 | ipv4, | ||
2210 | udp); | ||
2211 | GNUNET_assert (8 == sizeof(struct GNUNET_TUN_UdpHeader)); | ||
2212 | return sizeof(struct GNUNET_TUN_IPv4Header) + 8; | ||
2213 | } | ||
2214 | break; | ||
2215 | |||
2216 | case AF_INET6: | ||
2217 | { | ||
2218 | struct GNUNET_TUN_IPv6Header *ipv6; | ||
2219 | struct GNUNET_TUN_UdpHeader *udp; | ||
2220 | |||
2221 | ipv6 = (struct GNUNET_TUN_IPv6Header *) buf; | ||
2222 | udp = (struct GNUNET_TUN_UdpHeader *) &ipv6[1]; | ||
2223 | make_up_icmpv6_payload (state, | ||
2224 | ipv6, | ||
2225 | udp); | ||
2226 | GNUNET_assert (8 == sizeof(struct GNUNET_TUN_UdpHeader)); | ||
2227 | return sizeof(struct GNUNET_TUN_IPv6Header) + 8; | ||
2228 | } | ||
2229 | break; | ||
2230 | |||
2231 | default: | ||
2232 | GNUNET_break (0); | ||
2233 | } | ||
2234 | return 0; | ||
2235 | } | ||
2236 | |||
2237 | |||
2238 | /** | ||
2239 | * Check a request via cadet to send ICMP data to a service | ||
2240 | * offered by this system. | ||
2241 | * | ||
2242 | * @param cls our `struct ChannelState *` | ||
2243 | * @param msg the actual message | ||
2244 | * @return #GNUNET_OK to keep the connection open, | ||
2245 | * #GNUNET_SYSERR to close it (signal serious error) | ||
2246 | */ | ||
2247 | static int | ||
2248 | check_icmp_service (void *cls, | ||
2249 | const struct GNUNET_EXIT_IcmpServiceMessage *msg) | ||
2250 | { | ||
2251 | struct ChannelState *state = cls; | ||
2252 | |||
2253 | if (GNUNET_YES == state->is_dns) | ||
2254 | { | ||
2255 | GNUNET_break_op (0); | ||
2256 | return GNUNET_SYSERR; | ||
2257 | } | ||
2258 | if (NULL == state->specifics.tcp_udp.serv) | ||
2259 | { | ||
2260 | GNUNET_break_op (0); | ||
2261 | return GNUNET_SYSERR; | ||
2262 | } | ||
2263 | return GNUNET_OK; | ||
2264 | } | ||
2265 | |||
2266 | |||
2267 | /** | ||
2268 | * Process a request via cadet to send ICMP data to a service | ||
2269 | * offered by this system. | ||
2270 | * | ||
2271 | * @param cls our `struct ChannelState *` | ||
2272 | * @param msg the actual message | ||
2273 | */ | ||
2274 | static void | ||
2275 | handle_icmp_service (void *cls, | ||
2276 | const struct GNUNET_EXIT_IcmpServiceMessage *msg) | ||
2277 | { | ||
2278 | struct ChannelState *state = cls; | ||
2279 | uint16_t pkt_len = ntohs (msg->header.size) - sizeof(struct | ||
2280 | GNUNET_EXIT_IcmpServiceMessage); | ||
2281 | struct GNUNET_TUN_IcmpHeader icmp; | ||
2282 | char buf[sizeof(struct GNUNET_TUN_IPv6Header) + 8] GNUNET_ALIGN; | ||
2283 | const void *payload; | ||
2284 | |||
2285 | GNUNET_STATISTICS_update (stats, | ||
2286 | gettext_noop ("# Bytes received from CADET"), | ||
2287 | pkt_len, GNUNET_NO); | ||
2288 | GNUNET_STATISTICS_update (stats, | ||
2289 | gettext_noop ( | ||
2290 | "# ICMP service requests received via cadet"), | ||
2291 | 1, GNUNET_NO); | ||
2292 | /* check that we got at least a valid header */ | ||
2293 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
2294 | "Received data from %s for forwarding to ICMP service %s\n", | ||
2295 | GNUNET_i2s (&state->peer), | ||
2296 | GNUNET_h2s (&state->specifics.tcp_udp.serv->descriptor)); | ||
2297 | icmp = msg->icmp_header; | ||
2298 | payload = &msg[1]; | ||
2299 | state->specifics.tcp_udp.ri.remote_address | ||
2300 | = state->specifics.tcp_udp.serv->address; | ||
2301 | setup_state_record (state); | ||
2302 | |||
2303 | /* check that ICMP type is something we want to support, | ||
2304 | perform ICMP PT if needed and possibly make up payload */ | ||
2305 | switch (msg->af) | ||
2306 | { | ||
2307 | case AF_INET: | ||
2308 | switch (msg->icmp_header.type) | ||
2309 | { | ||
2310 | case GNUNET_TUN_ICMPTYPE_ECHO_REPLY: | ||
2311 | if (state->specifics.tcp_udp.serv->address.af == AF_INET6) | ||
2312 | icmp.type = GNUNET_TUN_ICMPTYPE6_ECHO_REPLY; | ||
2313 | break; | ||
2314 | |||
2315 | case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST: | ||
2316 | if (state->specifics.tcp_udp.serv->address.af == AF_INET6) | ||
2317 | icmp.type = GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST; | ||
2318 | break; | ||
2319 | |||
2320 | case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE: | ||
2321 | if (state->specifics.tcp_udp.serv->address.af == AF_INET6) | ||
2322 | icmp.type = GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE; | ||
2323 | if (0 != pkt_len) | ||
2324 | { | ||
2325 | GNUNET_break_op (0); | ||
2326 | return; | ||
2327 | } | ||
2328 | payload = buf; | ||
2329 | pkt_len = make_up_icmp_service_payload (state, buf); | ||
2330 | break; | ||
2331 | |||
2332 | case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED: | ||
2333 | if (state->specifics.tcp_udp.serv->address.af == AF_INET6) | ||
2334 | icmp.type = GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED; | ||
2335 | if (0 != pkt_len) | ||
2336 | { | ||
2337 | GNUNET_break_op (0); | ||
2338 | return; | ||
2339 | } | ||
2340 | payload = buf; | ||
2341 | pkt_len = make_up_icmp_service_payload (state, buf); | ||
2342 | break; | ||
2343 | |||
2344 | case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH: | ||
2345 | if (state->specifics.tcp_udp.serv->address.af == AF_INET6) | ||
2346 | { | ||
2347 | GNUNET_STATISTICS_update (stats, | ||
2348 | gettext_noop ( | ||
2349 | "# ICMPv4 packets dropped (impossible PT to v6)"), | ||
2350 | 1, GNUNET_NO); | ||
2351 | return; | ||
2352 | } | ||
2353 | if (0 != pkt_len) | ||
2354 | { | ||
2355 | GNUNET_break_op (0); | ||
2356 | return; | ||
2357 | } | ||
2358 | payload = buf; | ||
2359 | pkt_len = make_up_icmp_service_payload (state, buf); | ||
2360 | break; | ||
2361 | |||
2362 | default: | ||
2363 | GNUNET_break_op (0); | ||
2364 | GNUNET_STATISTICS_update (stats, | ||
2365 | gettext_noop ( | ||
2366 | "# ICMPv4 packets dropped (type not allowed)"), | ||
2367 | 1, GNUNET_NO); | ||
2368 | return; | ||
2369 | } | ||
2370 | /* end of AF_INET */ | ||
2371 | break; | ||
2372 | |||
2373 | case AF_INET6: | ||
2374 | switch (msg->icmp_header.type) | ||
2375 | { | ||
2376 | case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY: | ||
2377 | if (state->specifics.tcp_udp.serv->address.af == AF_INET) | ||
2378 | icmp.type = GNUNET_TUN_ICMPTYPE_ECHO_REPLY; | ||
2379 | break; | ||
2380 | |||
2381 | case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST: | ||
2382 | if (state->specifics.tcp_udp.serv->address.af == AF_INET) | ||
2383 | icmp.type = GNUNET_TUN_ICMPTYPE_ECHO_REQUEST; | ||
2384 | break; | ||
2385 | |||
2386 | case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE: | ||
2387 | if (state->specifics.tcp_udp.serv->address.af == AF_INET) | ||
2388 | icmp.type = GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE; | ||
2389 | if (0 != pkt_len) | ||
2390 | { | ||
2391 | GNUNET_break_op (0); | ||
2392 | return; | ||
2393 | } | ||
2394 | payload = buf; | ||
2395 | pkt_len = make_up_icmp_service_payload (state, buf); | ||
2396 | break; | ||
2397 | |||
2398 | case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED: | ||
2399 | if (state->specifics.tcp_udp.serv->address.af == AF_INET) | ||
2400 | icmp.type = GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED; | ||
2401 | if (0 != pkt_len) | ||
2402 | { | ||
2403 | GNUNET_break_op (0); | ||
2404 | return; | ||
2405 | } | ||
2406 | payload = buf; | ||
2407 | pkt_len = make_up_icmp_service_payload (state, buf); | ||
2408 | break; | ||
2409 | |||
2410 | case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG: | ||
2411 | case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM: | ||
2412 | if (state->specifics.tcp_udp.serv->address.af == AF_INET) | ||
2413 | { | ||
2414 | GNUNET_STATISTICS_update (stats, | ||
2415 | gettext_noop ( | ||
2416 | "# ICMPv6 packets dropped (impossible PT to v4)"), | ||
2417 | 1, GNUNET_NO); | ||
2418 | return; | ||
2419 | } | ||
2420 | if (0 != pkt_len) | ||
2421 | { | ||
2422 | GNUNET_break_op (0); | ||
2423 | return; | ||
2424 | } | ||
2425 | payload = buf; | ||
2426 | pkt_len = make_up_icmp_service_payload (state, buf); | ||
2427 | break; | ||
2428 | |||
2429 | default: | ||
2430 | GNUNET_break_op (0); | ||
2431 | GNUNET_STATISTICS_update (stats, | ||
2432 | gettext_noop ( | ||
2433 | "# ICMPv6 packets dropped (type not allowed)"), | ||
2434 | 1, GNUNET_NO); | ||
2435 | return; | ||
2436 | } | ||
2437 | /* end of AF_INET6 */ | ||
2438 | break; | ||
2439 | |||
2440 | default: | ||
2441 | GNUNET_break_op (0); | ||
2442 | return; | ||
2443 | } | ||
2444 | |||
2445 | send_icmp_packet_via_tun (&state->specifics.tcp_udp.ri.remote_address, | ||
2446 | &state->specifics.tcp_udp.ri.local_address, | ||
2447 | &icmp, | ||
2448 | payload, | ||
2449 | pkt_len); | ||
2450 | GNUNET_CADET_receive_done (state->channel); | ||
2451 | } | ||
2452 | |||
2453 | |||
2454 | /** | ||
2455 | * Free memory associated with a service record. | ||
2456 | * | ||
2457 | * @param cls unused | ||
2458 | * @param key service descriptor | ||
2459 | * @param value service record to free | ||
2460 | * @return #GNUNET_OK | ||
2461 | */ | ||
2462 | static int | ||
2463 | free_service_record (void *cls, | ||
2464 | const struct GNUNET_HashCode *key, | ||
2465 | void *value) | ||
2466 | { | ||
2467 | struct LocalService *service = value; | ||
2468 | |||
2469 | GNUNET_assert (GNUNET_YES == | ||
2470 | GNUNET_CONTAINER_multihashmap_remove (services, | ||
2471 | key, | ||
2472 | service)); | ||
2473 | GNUNET_CADET_close_port (service->port); | ||
2474 | GNUNET_free (service->name); | ||
2475 | GNUNET_free (service); | ||
2476 | return GNUNET_OK; | ||
2477 | } | ||
2478 | |||
2479 | |||
2480 | /** | ||
2481 | * Callback from CADET for new channels. | ||
2482 | * | ||
2483 | * @param cls closure | ||
2484 | * @param channel new handle to the channel | ||
2485 | * @param initiator peer that started the channel | ||
2486 | * @return initial channel context for the channel | ||
2487 | */ | ||
2488 | static void * | ||
2489 | new_service_channel (void *cls, | ||
2490 | struct GNUNET_CADET_Channel *channel, | ||
2491 | const struct GNUNET_PeerIdentity *initiator) | ||
2492 | { | ||
2493 | struct LocalService *ls = cls; | ||
2494 | struct ChannelState *s = GNUNET_new (struct ChannelState); | ||
2495 | |||
2496 | s->peer = *initiator; | ||
2497 | GNUNET_STATISTICS_update (stats, | ||
2498 | gettext_noop ("# Inbound CADET channels created"), | ||
2499 | 1, | ||
2500 | GNUNET_NO); | ||
2501 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
2502 | "Received inbound channel from `%s'\n", | ||
2503 | GNUNET_i2s (initiator)); | ||
2504 | s->channel = channel; | ||
2505 | s->specifics.tcp_udp.serv = ls; | ||
2506 | s->specifics.tcp_udp.ri.remote_address = ls->address; | ||
2507 | return s; | ||
2508 | } | ||
2509 | |||
2510 | |||
2511 | /** | ||
2512 | * Function called by cadet whenever an inbound channel is destroyed. | ||
2513 | * Should clean up any associated state. | ||
2514 | * | ||
2515 | * @param cls our `struct ChannelState *` | ||
2516 | * @param channel connection to the other end (henceforth invalid) | ||
2517 | */ | ||
2518 | static void | ||
2519 | clean_channel (void *cls, | ||
2520 | const struct GNUNET_CADET_Channel *channel) | ||
2521 | { | ||
2522 | struct ChannelState *s = cls; | ||
2523 | |||
2524 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
2525 | "Channel destroyed\n"); | ||
2526 | if (GNUNET_SYSERR == s->is_dns) | ||
2527 | { | ||
2528 | GNUNET_free (s); | ||
2529 | return; | ||
2530 | } | ||
2531 | if (GNUNET_YES == s->is_dns) | ||
2532 | { | ||
2533 | if (channels[s->specifics.dns.my_id] == s) | ||
2534 | channels[s->specifics.dns.my_id] = NULL; | ||
2535 | } | ||
2536 | else | ||
2537 | { | ||
2538 | if (NULL != s->specifics.tcp_udp.heap_node) | ||
2539 | { | ||
2540 | GNUNET_assert (GNUNET_YES == | ||
2541 | GNUNET_CONTAINER_multihashmap_remove (connections_map, | ||
2542 | &s->specifics.tcp_udp | ||
2543 | .state_key, | ||
2544 | s)); | ||
2545 | GNUNET_CONTAINER_heap_remove_node (s->specifics.tcp_udp.heap_node); | ||
2546 | s->specifics.tcp_udp.heap_node = NULL; | ||
2547 | } | ||
2548 | } | ||
2549 | GNUNET_free (s); | ||
2550 | } | ||
2551 | |||
2552 | |||
2553 | /** | ||
2554 | * Given a service descriptor and a destination port, find the | ||
2555 | * respective service entry. | ||
2556 | * | ||
2557 | * @param proto IPPROTO_TCP or IPPROTO_UDP | ||
2558 | * @param name name of the service | ||
2559 | * @param destination_port destination port | ||
2560 | * @param service service information record to store (service->name will be set). | ||
2561 | */ | ||
2562 | static void | ||
2563 | store_service (int proto, | ||
2564 | const char *name, | ||
2565 | uint16_t destination_port, | ||
2566 | struct LocalService *service) | ||
2567 | { | ||
2568 | struct GNUNET_MQ_MessageHandler handlers[] = { | ||
2569 | GNUNET_MQ_hd_var_size (icmp_service, | ||
2570 | GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_SERVICE, | ||
2571 | struct GNUNET_EXIT_IcmpServiceMessage, | ||
2572 | service), | ||
2573 | GNUNET_MQ_hd_var_size (udp_service, | ||
2574 | GNUNET_MESSAGE_TYPE_VPN_UDP_TO_SERVICE, | ||
2575 | struct GNUNET_EXIT_UdpServiceMessage, | ||
2576 | service), | ||
2577 | GNUNET_MQ_hd_var_size (tcp_service, | ||
2578 | GNUNET_MESSAGE_TYPE_VPN_TCP_TO_SERVICE_START, | ||
2579 | struct GNUNET_EXIT_TcpServiceStartMessage, | ||
2580 | service), | ||
2581 | GNUNET_MQ_hd_var_size (tcp_data, | ||
2582 | GNUNET_MESSAGE_TYPE_VPN_TCP_DATA_TO_EXIT, | ||
2583 | struct GNUNET_EXIT_TcpDataMessage, | ||
2584 | service), | ||
2585 | GNUNET_MQ_handler_end () | ||
2586 | }; | ||
2587 | |||
2588 | struct GNUNET_HashCode cadet_port; | ||
2589 | |||
2590 | service->name = GNUNET_strdup (name); | ||
2591 | GNUNET_TUN_service_name_to_hash (name, | ||
2592 | &service->descriptor); | ||
2593 | GNUNET_TUN_compute_service_cadet_port (&service->descriptor, | ||
2594 | destination_port, | ||
2595 | &cadet_port); | ||
2596 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
2597 | "Opening CADET port %s for SERVICE exit %s on port %u\n", | ||
2598 | GNUNET_h2s (&cadet_port), | ||
2599 | name, | ||
2600 | (unsigned int) destination_port); | ||
2601 | service->port = GNUNET_CADET_open_port (cadet_handle, | ||
2602 | &cadet_port, | ||
2603 | &new_service_channel, | ||
2604 | service, | ||
2605 | NULL, | ||
2606 | &clean_channel, | ||
2607 | handlers); | ||
2608 | service->is_udp = (IPPROTO_UDP == proto); | ||
2609 | if (GNUNET_OK != | ||
2610 | GNUNET_CONTAINER_multihashmap_put (services, | ||
2611 | &cadet_port, | ||
2612 | service, | ||
2613 | GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)) | ||
2614 | { | ||
2615 | GNUNET_CADET_close_port (service->port); | ||
2616 | GNUNET_free (service->name); | ||
2617 | GNUNET_free (service); | ||
2618 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
2619 | _ ("Got duplicate service records for `%s:%u'\n"), | ||
2620 | name, | ||
2621 | (unsigned int) destination_port); | ||
2622 | } | ||
2623 | } | ||
2624 | |||
2625 | |||
2626 | /** | ||
2627 | * Send the given packet via the cadet channel. | ||
2628 | * | ||
2629 | * @param s channel destination | ||
2630 | * @param env message to queue | ||
2631 | */ | ||
2632 | static void | ||
2633 | send_packet_to_cadet_channel (struct ChannelState *s, | ||
2634 | struct GNUNET_MQ_Envelope *env) | ||
2635 | { | ||
2636 | GNUNET_assert (NULL != s); | ||
2637 | GNUNET_STATISTICS_update (stats, | ||
2638 | gettext_noop ( | ||
2639 | "# Messages transmitted via cadet channels"), | ||
2640 | 1, | ||
2641 | GNUNET_NO); | ||
2642 | GNUNET_MQ_send (GNUNET_CADET_get_mq (s->channel), | ||
2643 | env); | ||
2644 | } | ||
2645 | |||
2646 | |||
2647 | /** | ||
2648 | * @brief Handles an ICMP packet received from the helper. | ||
2649 | * | ||
2650 | * @param icmp A pointer to the Packet | ||
2651 | * @param pktlen number of bytes in @a icmp | ||
2652 | * @param af address family (AFINET or AF_INET6) | ||
2653 | * @param destination_ip destination IP-address of the IP packet (should | ||
2654 | * be our local address) | ||
2655 | * @param source_ip original source IP-address of the IP packet (should | ||
2656 | * be the original destination address) | ||
2657 | */ | ||
2658 | static void | ||
2659 | icmp_from_helper (const struct GNUNET_TUN_IcmpHeader *icmp, | ||
2660 | size_t pktlen, | ||
2661 | int af, | ||
2662 | const void *destination_ip, | ||
2663 | const void *source_ip) | ||
2664 | { | ||
2665 | struct ChannelState *state; | ||
2666 | struct GNUNET_MQ_Envelope *env; | ||
2667 | struct GNUNET_EXIT_IcmpToVPNMessage *i2v; | ||
2668 | const struct GNUNET_TUN_IPv4Header *ipv4; | ||
2669 | const struct GNUNET_TUN_IPv6Header *ipv6; | ||
2670 | const struct GNUNET_TUN_UdpHeader *udp; | ||
2671 | uint16_t source_port; | ||
2672 | uint16_t destination_port; | ||
2673 | uint8_t protocol; | ||
2674 | |||
2675 | { | ||
2676 | char sbuf[INET6_ADDRSTRLEN]; | ||
2677 | char dbuf[INET6_ADDRSTRLEN]; | ||
2678 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
2679 | "Received ICMP packet going from %s to %s\n", | ||
2680 | inet_ntop (af, | ||
2681 | source_ip, | ||
2682 | sbuf, sizeof(sbuf)), | ||
2683 | inet_ntop (af, | ||
2684 | destination_ip, | ||
2685 | dbuf, sizeof(dbuf))); | ||
2686 | } | ||
2687 | |||
2688 | if (pktlen < sizeof(struct GNUNET_TUN_IcmpHeader)) | ||
2689 | { | ||
2690 | /* blame kernel */ | ||
2691 | GNUNET_break (0); | ||
2692 | return; | ||
2693 | } | ||
2694 | |||
2695 | /* Find out if this is an ICMP packet in response to an existing | ||
2696 | TCP/UDP packet and if so, figure out ports / protocol of the | ||
2697 | existing session from the IP data in the ICMP payload */ | ||
2698 | source_port = 0; | ||
2699 | destination_port = 0; | ||
2700 | switch (af) | ||
2701 | { | ||
2702 | case AF_INET: | ||
2703 | protocol = IPPROTO_ICMP; | ||
2704 | switch (icmp->type) | ||
2705 | { | ||
2706 | case GNUNET_TUN_ICMPTYPE_ECHO_REPLY: | ||
2707 | case GNUNET_TUN_ICMPTYPE_ECHO_REQUEST: | ||
2708 | break; | ||
2709 | |||
2710 | case GNUNET_TUN_ICMPTYPE_DESTINATION_UNREACHABLE: | ||
2711 | case GNUNET_TUN_ICMPTYPE_SOURCE_QUENCH: | ||
2712 | case GNUNET_TUN_ICMPTYPE_TIME_EXCEEDED: | ||
2713 | if (pktlen < | ||
2714 | sizeof(struct GNUNET_TUN_IcmpHeader) | ||
2715 | + sizeof(struct GNUNET_TUN_IPv4Header) + 8) | ||
2716 | { | ||
2717 | /* blame kernel */ | ||
2718 | GNUNET_break (0); | ||
2719 | return; | ||
2720 | } | ||
2721 | ipv4 = (const struct GNUNET_TUN_IPv4Header *) &icmp[1]; | ||
2722 | protocol = ipv4->protocol; | ||
2723 | /* could be TCP or UDP, but both have the ports in the right | ||
2724 | place, so that doesn't matter here */ | ||
2725 | udp = (const struct GNUNET_TUN_UdpHeader *) &ipv4[1]; | ||
2726 | /* swap ports, as they are from the original message */ | ||
2727 | destination_port = ntohs (udp->source_port); | ||
2728 | source_port = ntohs (udp->destination_port); | ||
2729 | /* throw away ICMP payload, won't be useful for the other side anyway */ | ||
2730 | pktlen = sizeof(struct GNUNET_TUN_IcmpHeader); | ||
2731 | break; | ||
2732 | |||
2733 | default: | ||
2734 | GNUNET_STATISTICS_update (stats, | ||
2735 | gettext_noop ( | ||
2736 | "# ICMPv4 packets dropped (type not allowed)"), | ||
2737 | 1, GNUNET_NO); | ||
2738 | return; | ||
2739 | } | ||
2740 | break; | ||
2741 | |||
2742 | case AF_INET6: | ||
2743 | protocol = IPPROTO_ICMPV6; | ||
2744 | switch (icmp->type) | ||
2745 | { | ||
2746 | case GNUNET_TUN_ICMPTYPE6_DESTINATION_UNREACHABLE: | ||
2747 | case GNUNET_TUN_ICMPTYPE6_PACKET_TOO_BIG: | ||
2748 | case GNUNET_TUN_ICMPTYPE6_TIME_EXCEEDED: | ||
2749 | case GNUNET_TUN_ICMPTYPE6_PARAMETER_PROBLEM: | ||
2750 | if (pktlen < | ||
2751 | sizeof(struct GNUNET_TUN_IcmpHeader) | ||
2752 | + sizeof(struct GNUNET_TUN_IPv6Header) + 8) | ||
2753 | { | ||
2754 | /* blame kernel */ | ||
2755 | GNUNET_break (0); | ||
2756 | return; | ||
2757 | } | ||
2758 | ipv6 = (const struct GNUNET_TUN_IPv6Header *) &icmp[1]; | ||
2759 | protocol = ipv6->next_header; | ||
2760 | /* could be TCP or UDP, but both have the ports in the right | ||
2761 | place, so that doesn't matter here */ | ||
2762 | udp = (const struct GNUNET_TUN_UdpHeader *) &ipv6[1]; | ||
2763 | /* swap ports, as they are from the original message */ | ||
2764 | destination_port = ntohs (udp->source_port); | ||
2765 | source_port = ntohs (udp->destination_port); | ||
2766 | /* throw away ICMP payload, won't be useful for the other side anyway */ | ||
2767 | pktlen = sizeof(struct GNUNET_TUN_IcmpHeader); | ||
2768 | break; | ||
2769 | |||
2770 | case GNUNET_TUN_ICMPTYPE6_ECHO_REQUEST: | ||
2771 | case GNUNET_TUN_ICMPTYPE6_ECHO_REPLY: | ||
2772 | break; | ||
2773 | |||
2774 | default: | ||
2775 | GNUNET_STATISTICS_update (stats, | ||
2776 | gettext_noop ( | ||
2777 | "# ICMPv6 packets dropped (type not allowed)"), | ||
2778 | 1, GNUNET_NO); | ||
2779 | return; | ||
2780 | } | ||
2781 | break; | ||
2782 | |||
2783 | default: | ||
2784 | GNUNET_assert (0); | ||
2785 | } | ||
2786 | switch (protocol) | ||
2787 | { | ||
2788 | case IPPROTO_ICMP: | ||
2789 | state = get_redirect_state (af, | ||
2790 | IPPROTO_ICMP, | ||
2791 | source_ip, | ||
2792 | 0, | ||
2793 | destination_ip, | ||
2794 | 0, | ||
2795 | NULL); | ||
2796 | break; | ||
2797 | |||
2798 | case IPPROTO_ICMPV6: | ||
2799 | state = get_redirect_state (af, | ||
2800 | IPPROTO_ICMPV6, | ||
2801 | source_ip, | ||
2802 | 0, | ||
2803 | destination_ip, | ||
2804 | 0, | ||
2805 | NULL); | ||
2806 | break; | ||
2807 | |||
2808 | case IPPROTO_UDP: | ||
2809 | state = get_redirect_state (af, | ||
2810 | IPPROTO_UDP, | ||
2811 | source_ip, | ||
2812 | source_port, | ||
2813 | destination_ip, | ||
2814 | destination_port, | ||
2815 | NULL); | ||
2816 | break; | ||
2817 | |||
2818 | case IPPROTO_TCP: | ||
2819 | state = get_redirect_state (af, | ||
2820 | IPPROTO_TCP, | ||
2821 | source_ip, | ||
2822 | source_port, | ||
2823 | destination_ip, | ||
2824 | destination_port, | ||
2825 | NULL); | ||
2826 | break; | ||
2827 | |||
2828 | default: | ||
2829 | GNUNET_STATISTICS_update (stats, | ||
2830 | gettext_noop ( | ||
2831 | "# ICMP packets dropped (not allowed)"), | ||
2832 | 1, | ||
2833 | GNUNET_NO); | ||
2834 | return; | ||
2835 | } | ||
2836 | if (NULL == state) | ||
2837 | { | ||
2838 | GNUNET_log (GNUNET_ERROR_TYPE_INFO, | ||
2839 | _ ( | ||
2840 | "ICMP Packet dropped, have no matching connection information\n")); | ||
2841 | return; | ||
2842 | } | ||
2843 | env = GNUNET_MQ_msg_extra (i2v, | ||
2844 | pktlen - sizeof(struct GNUNET_TUN_IcmpHeader), | ||
2845 | GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_VPN); | ||
2846 | i2v->af = htonl (af); | ||
2847 | GNUNET_memcpy (&i2v->icmp_header, | ||
2848 | icmp, | ||
2849 | pktlen); | ||
2850 | send_packet_to_cadet_channel (state, | ||
2851 | env); | ||
2852 | } | ||
2853 | |||
2854 | |||
2855 | /** | ||
2856 | * @brief Handles an UDP packet received from the helper. | ||
2857 | * | ||
2858 | * @param udp A pointer to the Packet | ||
2859 | * @param pktlen number of bytes in 'udp' | ||
2860 | * @param af address family (AFINET or AF_INET6) | ||
2861 | * @param destination_ip destination IP-address of the IP packet (should | ||
2862 | * be our local address) | ||
2863 | * @param source_ip original source IP-address of the IP packet (should | ||
2864 | * be the original destination address) | ||
2865 | */ | ||
2866 | static void | ||
2867 | udp_from_helper (const struct GNUNET_TUN_UdpHeader *udp, | ||
2868 | size_t pktlen, | ||
2869 | int af, | ||
2870 | const void *destination_ip, | ||
2871 | const void *source_ip) | ||
2872 | { | ||
2873 | struct ChannelState *state; | ||
2874 | struct GNUNET_MQ_Envelope *env; | ||
2875 | struct GNUNET_EXIT_UdpReplyMessage *urm; | ||
2876 | |||
2877 | { | ||
2878 | char sbuf[INET6_ADDRSTRLEN]; | ||
2879 | char dbuf[INET6_ADDRSTRLEN]; | ||
2880 | |||
2881 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
2882 | "Received UDP packet going from %s:%u to %s:%u\n", | ||
2883 | inet_ntop (af, | ||
2884 | source_ip, | ||
2885 | sbuf, sizeof(sbuf)), | ||
2886 | (unsigned int) ntohs (udp->source_port), | ||
2887 | inet_ntop (af, | ||
2888 | destination_ip, | ||
2889 | dbuf, sizeof(dbuf)), | ||
2890 | (unsigned int) ntohs (udp->destination_port)); | ||
2891 | } | ||
2892 | |||
2893 | if (pktlen < sizeof(struct GNUNET_TUN_UdpHeader)) | ||
2894 | { | ||
2895 | /* blame kernel */ | ||
2896 | GNUNET_break (0); | ||
2897 | return; | ||
2898 | } | ||
2899 | if (pktlen != ntohs (udp->len)) | ||
2900 | { | ||
2901 | /* blame kernel */ | ||
2902 | GNUNET_break (0); | ||
2903 | return; | ||
2904 | } | ||
2905 | state = get_redirect_state (af, | ||
2906 | IPPROTO_UDP, | ||
2907 | source_ip, | ||
2908 | ntohs (udp->source_port), | ||
2909 | destination_ip, | ||
2910 | ntohs (udp->destination_port), | ||
2911 | NULL); | ||
2912 | if (NULL == state) | ||
2913 | { | ||
2914 | GNUNET_log (GNUNET_ERROR_TYPE_INFO, | ||
2915 | _ ( | ||
2916 | "UDP Packet dropped, have no matching connection information\n")); | ||
2917 | return; | ||
2918 | } | ||
2919 | env = GNUNET_MQ_msg_extra (urm, | ||
2920 | pktlen - sizeof(struct GNUNET_TUN_UdpHeader), | ||
2921 | GNUNET_MESSAGE_TYPE_VPN_UDP_REPLY); | ||
2922 | urm->source_port = htons (0); | ||
2923 | urm->destination_port = htons (0); | ||
2924 | GNUNET_memcpy (&urm[1], | ||
2925 | &udp[1], | ||
2926 | pktlen - sizeof(struct GNUNET_TUN_UdpHeader)); | ||
2927 | send_packet_to_cadet_channel (state, | ||
2928 | env); | ||
2929 | } | ||
2930 | |||
2931 | |||
2932 | /** | ||
2933 | * @brief Handles a TCP packet received from the helper. | ||
2934 | * | ||
2935 | * @param tcp A pointer to the Packet | ||
2936 | * @param pktlen the length of the packet, including its TCP header | ||
2937 | * @param af address family (AFINET or AF_INET6) | ||
2938 | * @param destination_ip destination IP-address of the IP packet (should | ||
2939 | * be our local address) | ||
2940 | * @param source_ip original source IP-address of the IP packet (should | ||
2941 | * be the original destination address) | ||
2942 | */ | ||
2943 | static void | ||
2944 | tcp_from_helper (const struct GNUNET_TUN_TcpHeader *tcp, | ||
2945 | size_t pktlen, | ||
2946 | int af, | ||
2947 | const void *destination_ip, | ||
2948 | const void *source_ip) | ||
2949 | { | ||
2950 | struct ChannelState *state; | ||
2951 | char buf[pktlen] GNUNET_ALIGN; | ||
2952 | struct GNUNET_TUN_TcpHeader *mtcp; | ||
2953 | struct GNUNET_EXIT_TcpDataMessage *tdm; | ||
2954 | struct GNUNET_MQ_Envelope *env; | ||
2955 | size_t mlen; | ||
2956 | |||
2957 | { | ||
2958 | char sbuf[INET6_ADDRSTRLEN]; | ||
2959 | char dbuf[INET6_ADDRSTRLEN]; | ||
2960 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
2961 | "Received TCP packet with %u bytes going from %s:%u to %s:%u\n", | ||
2962 | (unsigned int) (pktlen - sizeof(struct GNUNET_TUN_TcpHeader)), | ||
2963 | inet_ntop (af, | ||
2964 | source_ip, | ||
2965 | sbuf, sizeof(sbuf)), | ||
2966 | (unsigned int) ntohs (tcp->source_port), | ||
2967 | inet_ntop (af, | ||
2968 | destination_ip, | ||
2969 | dbuf, sizeof(dbuf)), | ||
2970 | (unsigned int) ntohs (tcp->destination_port)); | ||
2971 | } | ||
2972 | |||
2973 | if (pktlen < sizeof(struct GNUNET_TUN_TcpHeader)) | ||
2974 | { | ||
2975 | /* blame kernel */ | ||
2976 | GNUNET_break (0); | ||
2977 | return; | ||
2978 | } | ||
2979 | state = get_redirect_state (af, | ||
2980 | IPPROTO_TCP, | ||
2981 | source_ip, | ||
2982 | ntohs (tcp->source_port), | ||
2983 | destination_ip, | ||
2984 | ntohs (tcp->destination_port), | ||
2985 | NULL); | ||
2986 | if (NULL == state) | ||
2987 | { | ||
2988 | GNUNET_log (GNUNET_ERROR_TYPE_INFO, | ||
2989 | _ ( | ||
2990 | "TCP Packet dropped, have no matching connection information\n")); | ||
2991 | |||
2992 | return; | ||
2993 | } | ||
2994 | /* mug port numbers and crc to avoid information leakage; | ||
2995 | sender will need to lookup the correct values anyway */ | ||
2996 | GNUNET_memcpy (buf, tcp, pktlen); | ||
2997 | mtcp = (struct GNUNET_TUN_TcpHeader *) buf; | ||
2998 | mtcp->source_port = 0; | ||
2999 | mtcp->destination_port = 0; | ||
3000 | mtcp->crc = 0; | ||
3001 | |||
3002 | mlen = sizeof(struct GNUNET_EXIT_TcpDataMessage) + (pktlen - sizeof(struct | ||
3003 | GNUNET_TUN_TcpHeader)); | ||
3004 | if (mlen >= GNUNET_MAX_MESSAGE_SIZE) | ||
3005 | { | ||
3006 | GNUNET_break (0); | ||
3007 | return; | ||
3008 | } | ||
3009 | env = GNUNET_MQ_msg_extra (tdm, | ||
3010 | pktlen - sizeof(struct GNUNET_TUN_TcpHeader), | ||
3011 | GNUNET_MESSAGE_TYPE_VPN_TCP_DATA_TO_VPN); | ||
3012 | tdm->reserved = htonl (0); | ||
3013 | GNUNET_memcpy (&tdm->tcp_header, | ||
3014 | buf, | ||
3015 | pktlen); | ||
3016 | send_packet_to_cadet_channel (state, | ||
3017 | env); | ||
3018 | } | ||
3019 | |||
3020 | |||
3021 | /** | ||
3022 | * Receive packets from the helper-process | ||
3023 | * | ||
3024 | * @param cls unused | ||
3025 | * @param message message received from helper | ||
3026 | */ | ||
3027 | static int | ||
3028 | message_token (void *cls GNUNET_UNUSED, | ||
3029 | const struct GNUNET_MessageHeader *message) | ||
3030 | { | ||
3031 | const struct GNUNET_TUN_Layer2PacketHeader *pkt_tun; | ||
3032 | size_t size; | ||
3033 | |||
3034 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
3035 | "Got %u-byte message of type %u from gnunet-helper-exit\n", | ||
3036 | ntohs (message->size), | ||
3037 | ntohs (message->type)); | ||
3038 | GNUNET_STATISTICS_update (stats, | ||
3039 | gettext_noop ("# Packets received from TUN"), | ||
3040 | 1, GNUNET_NO); | ||
3041 | if (ntohs (message->type) != GNUNET_MESSAGE_TYPE_VPN_HELPER) | ||
3042 | { | ||
3043 | GNUNET_break (0); | ||
3044 | return GNUNET_OK; | ||
3045 | } | ||
3046 | size = ntohs (message->size); | ||
3047 | if (size < sizeof(struct GNUNET_TUN_Layer2PacketHeader) + sizeof(struct | ||
3048 | GNUNET_MessageHeader)) | ||
3049 | { | ||
3050 | GNUNET_break (0); | ||
3051 | return GNUNET_OK; | ||
3052 | } | ||
3053 | GNUNET_STATISTICS_update (stats, | ||
3054 | gettext_noop ("# Bytes received from TUN"), | ||
3055 | size, GNUNET_NO); | ||
3056 | pkt_tun = (const struct GNUNET_TUN_Layer2PacketHeader *) &message[1]; | ||
3057 | size -= sizeof(struct GNUNET_TUN_Layer2PacketHeader) + sizeof(struct | ||
3058 | GNUNET_MessageHeader); | ||
3059 | switch (ntohs (pkt_tun->proto)) | ||
3060 | { | ||
3061 | case ETH_P_IPV4: | ||
3062 | { | ||
3063 | const struct GNUNET_TUN_IPv4Header *pkt4; | ||
3064 | |||
3065 | if (size < sizeof(struct GNUNET_TUN_IPv4Header)) | ||
3066 | { | ||
3067 | /* Kernel to blame? */ | ||
3068 | GNUNET_break (0); | ||
3069 | return GNUNET_OK; | ||
3070 | } | ||
3071 | pkt4 = (const struct GNUNET_TUN_IPv4Header *) &pkt_tun[1]; | ||
3072 | if (size != ntohs (pkt4->total_length)) | ||
3073 | { | ||
3074 | /* Kernel to blame? */ | ||
3075 | GNUNET_break (0); | ||
3076 | return GNUNET_OK; | ||
3077 | } | ||
3078 | if (pkt4->header_length * 4 != sizeof(struct GNUNET_TUN_IPv4Header)) | ||
3079 | { | ||
3080 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3081 | _ ("IPv4 packet options received. Ignored.\n")); | ||
3082 | return GNUNET_OK; | ||
3083 | } | ||
3084 | |||
3085 | size -= sizeof(struct GNUNET_TUN_IPv4Header); | ||
3086 | switch (pkt4->protocol) | ||
3087 | { | ||
3088 | case IPPROTO_UDP: | ||
3089 | udp_from_helper ((const struct GNUNET_TUN_UdpHeader *) &pkt4[1], size, | ||
3090 | AF_INET, | ||
3091 | &pkt4->destination_address, | ||
3092 | &pkt4->source_address); | ||
3093 | break; | ||
3094 | |||
3095 | case IPPROTO_TCP: | ||
3096 | tcp_from_helper ((const struct GNUNET_TUN_TcpHeader *) &pkt4[1], size, | ||
3097 | AF_INET, | ||
3098 | &pkt4->destination_address, | ||
3099 | &pkt4->source_address); | ||
3100 | break; | ||
3101 | |||
3102 | case IPPROTO_ICMP: | ||
3103 | icmp_from_helper ((const struct GNUNET_TUN_IcmpHeader *) &pkt4[1], size, | ||
3104 | AF_INET, | ||
3105 | &pkt4->destination_address, | ||
3106 | &pkt4->source_address); | ||
3107 | break; | ||
3108 | |||
3109 | default: | ||
3110 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3111 | _ ( | ||
3112 | "IPv4 packet with unsupported next header %u received. Ignored.\n"), | ||
3113 | (int) pkt4->protocol); | ||
3114 | return GNUNET_OK; | ||
3115 | } | ||
3116 | } | ||
3117 | break; | ||
3118 | |||
3119 | case ETH_P_IPV6: | ||
3120 | { | ||
3121 | const struct GNUNET_TUN_IPv6Header *pkt6; | ||
3122 | |||
3123 | if (size < sizeof(struct GNUNET_TUN_IPv6Header)) | ||
3124 | { | ||
3125 | /* Kernel to blame? */ | ||
3126 | GNUNET_break (0); | ||
3127 | return GNUNET_OK; | ||
3128 | } | ||
3129 | pkt6 = (struct GNUNET_TUN_IPv6Header *) &pkt_tun[1]; | ||
3130 | if (size != ntohs (pkt6->payload_length) + sizeof(struct | ||
3131 | GNUNET_TUN_IPv6Header)) | ||
3132 | { | ||
3133 | /* Kernel to blame? */ | ||
3134 | GNUNET_break (0); | ||
3135 | return GNUNET_OK; | ||
3136 | } | ||
3137 | size -= sizeof(struct GNUNET_TUN_IPv6Header); | ||
3138 | switch (pkt6->next_header) | ||
3139 | { | ||
3140 | case IPPROTO_UDP: | ||
3141 | udp_from_helper ((const struct GNUNET_TUN_UdpHeader *) &pkt6[1], size, | ||
3142 | AF_INET6, | ||
3143 | &pkt6->destination_address, | ||
3144 | &pkt6->source_address); | ||
3145 | break; | ||
3146 | |||
3147 | case IPPROTO_TCP: | ||
3148 | tcp_from_helper ((const struct GNUNET_TUN_TcpHeader *) &pkt6[1], size, | ||
3149 | AF_INET6, | ||
3150 | &pkt6->destination_address, | ||
3151 | &pkt6->source_address); | ||
3152 | break; | ||
3153 | |||
3154 | case IPPROTO_ICMPV6: | ||
3155 | icmp_from_helper ((const struct GNUNET_TUN_IcmpHeader *) &pkt6[1], size, | ||
3156 | AF_INET6, | ||
3157 | &pkt6->destination_address, | ||
3158 | &pkt6->source_address); | ||
3159 | break; | ||
3160 | |||
3161 | default: | ||
3162 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3163 | _ ( | ||
3164 | "IPv6 packet with unsupported next header %d received. Ignored.\n"), | ||
3165 | pkt6->next_header); | ||
3166 | return GNUNET_OK; | ||
3167 | } | ||
3168 | } | ||
3169 | break; | ||
3170 | |||
3171 | default: | ||
3172 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3173 | _ ("Packet from unknown protocol %u received. Ignored.\n"), | ||
3174 | ntohs (pkt_tun->proto)); | ||
3175 | break; | ||
3176 | } | ||
3177 | return GNUNET_OK; | ||
3178 | } | ||
3179 | |||
3180 | |||
3181 | /** | ||
3182 | * Callback from CADET for new channels. | ||
3183 | * | ||
3184 | * @param cls closure | ||
3185 | * @param channel new handle to the channel | ||
3186 | * @param initiator peer that started the channel | ||
3187 | * @return initial channel context for the channel | ||
3188 | */ | ||
3189 | static void * | ||
3190 | new_channel (void *cls, | ||
3191 | struct GNUNET_CADET_Channel *channel, | ||
3192 | const struct GNUNET_PeerIdentity *initiator) | ||
3193 | { | ||
3194 | struct ChannelState *s = GNUNET_new (struct ChannelState); | ||
3195 | |||
3196 | s->is_dns = GNUNET_SYSERR; | ||
3197 | s->peer = *initiator; | ||
3198 | GNUNET_STATISTICS_update (stats, | ||
3199 | gettext_noop ("# Inbound CADET channels created"), | ||
3200 | 1, | ||
3201 | GNUNET_NO); | ||
3202 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
3203 | "Received inbound channel from `%s'\n", | ||
3204 | GNUNET_i2s (initiator)); | ||
3205 | s->channel = channel; | ||
3206 | return s; | ||
3207 | } | ||
3208 | |||
3209 | |||
3210 | /** | ||
3211 | * Function that frees everything from a hashmap | ||
3212 | * | ||
3213 | * @param cls unused | ||
3214 | * @param hash key | ||
3215 | * @param value value to free | ||
3216 | */ | ||
3217 | static int | ||
3218 | free_iterate (void *cls, | ||
3219 | const struct GNUNET_HashCode *hash, | ||
3220 | void *value) | ||
3221 | { | ||
3222 | GNUNET_free (value); | ||
3223 | return GNUNET_YES; | ||
3224 | } | ||
3225 | |||
3226 | |||
3227 | /** | ||
3228 | * Function scheduled as very last function if the service | ||
3229 | * disabled itself because the helper is not installed | ||
3230 | * properly. Does nothing, except for keeping the | ||
3231 | * service process alive by virtue of being scheduled. | ||
3232 | * | ||
3233 | * @param cls NULL | ||
3234 | * @param tc scheduler context | ||
3235 | */ | ||
3236 | static void | ||
3237 | dummy_task (void *cls) | ||
3238 | { | ||
3239 | /* just terminate */ | ||
3240 | } | ||
3241 | |||
3242 | |||
3243 | /** | ||
3244 | * Function scheduled as very last function, cleans up after us | ||
3245 | * | ||
3246 | * @param cls NULL | ||
3247 | */ | ||
3248 | static void | ||
3249 | cleanup (void *cls) | ||
3250 | { | ||
3251 | unsigned int i; | ||
3252 | |||
3253 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
3254 | "Exit service is shutting down now\n"); | ||
3255 | |||
3256 | if (NULL != helper_handle) | ||
3257 | { | ||
3258 | GNUNET_HELPER_stop (helper_handle, GNUNET_NO); | ||
3259 | helper_handle = NULL; | ||
3260 | } | ||
3261 | if (NULL != regex4) | ||
3262 | { | ||
3263 | GNUNET_REGEX_announce_cancel (regex4); | ||
3264 | regex4 = NULL; | ||
3265 | } | ||
3266 | if (NULL != regex6) | ||
3267 | { | ||
3268 | GNUNET_REGEX_announce_cancel (regex6); | ||
3269 | regex6 = NULL; | ||
3270 | } | ||
3271 | if (NULL != services) | ||
3272 | { | ||
3273 | GNUNET_CONTAINER_multihashmap_iterate (services, | ||
3274 | &free_service_record, | ||
3275 | NULL); | ||
3276 | GNUNET_CONTAINER_multihashmap_destroy (services); | ||
3277 | } | ||
3278 | if (NULL != dns_port) | ||
3279 | { | ||
3280 | GNUNET_CADET_close_port (dns_port); | ||
3281 | dns_port = NULL; | ||
3282 | } | ||
3283 | if (NULL != cadet_port4) | ||
3284 | { | ||
3285 | GNUNET_CADET_close_port (cadet_port4); | ||
3286 | cadet_port4 = NULL; | ||
3287 | } | ||
3288 | if (NULL != cadet_port6) | ||
3289 | { | ||
3290 | GNUNET_CADET_close_port (cadet_port6); | ||
3291 | cadet_port6 = NULL; | ||
3292 | } | ||
3293 | if (NULL != cadet_handle) | ||
3294 | { | ||
3295 | GNUNET_CADET_disconnect (cadet_handle); | ||
3296 | cadet_handle = NULL; | ||
3297 | } | ||
3298 | if (NULL != connections_map) | ||
3299 | { | ||
3300 | GNUNET_CONTAINER_multihashmap_iterate (connections_map, | ||
3301 | &free_iterate, | ||
3302 | NULL); | ||
3303 | GNUNET_CONTAINER_multihashmap_destroy (connections_map); | ||
3304 | connections_map = NULL; | ||
3305 | } | ||
3306 | if (NULL != connections_heap) | ||
3307 | { | ||
3308 | GNUNET_CONTAINER_heap_destroy (connections_heap); | ||
3309 | connections_heap = NULL; | ||
3310 | } | ||
3311 | if (NULL != dnsstub) | ||
3312 | { | ||
3313 | GNUNET_DNSSTUB_stop (dnsstub); | ||
3314 | dnsstub = NULL; | ||
3315 | } | ||
3316 | if (NULL != peer_key) | ||
3317 | { | ||
3318 | GNUNET_free (peer_key); | ||
3319 | peer_key = NULL; | ||
3320 | } | ||
3321 | if (NULL != dht_task) | ||
3322 | { | ||
3323 | GNUNET_SCHEDULER_cancel (dht_task); | ||
3324 | dht_task = NULL; | ||
3325 | } | ||
3326 | if (NULL != dht_put) | ||
3327 | { | ||
3328 | GNUNET_DHT_put_cancel (dht_put); | ||
3329 | dht_put = NULL; | ||
3330 | } | ||
3331 | if (NULL != dht) | ||
3332 | { | ||
3333 | GNUNET_DHT_disconnect (dht); | ||
3334 | dht = NULL; | ||
3335 | } | ||
3336 | if (NULL != stats) | ||
3337 | { | ||
3338 | GNUNET_STATISTICS_destroy (stats, | ||
3339 | GNUNET_NO); | ||
3340 | stats = NULL; | ||
3341 | } | ||
3342 | for (i = 0; i < 8; i++) | ||
3343 | GNUNET_free (exit_argv[i]); | ||
3344 | } | ||
3345 | |||
3346 | |||
3347 | /** | ||
3348 | * Add services to the service map. | ||
3349 | * | ||
3350 | * @param proto IPPROTO_TCP or IPPROTO_UDP | ||
3351 | * @param cpy copy of the service descriptor (can be mutilated) | ||
3352 | * @param name DNS name of the service | ||
3353 | */ | ||
3354 | static void | ||
3355 | add_services (int proto, | ||
3356 | char *cpy, | ||
3357 | const char *name) | ||
3358 | { | ||
3359 | char *redirect; | ||
3360 | char *hostname; | ||
3361 | char *hostport; | ||
3362 | struct LocalService *serv; | ||
3363 | char *n; | ||
3364 | size_t slen; | ||
3365 | |||
3366 | slen = strlen (name); | ||
3367 | GNUNET_assert (slen >= 8); | ||
3368 | n = GNUNET_strndup (name, slen - 8 /* remove .gnunet. */); | ||
3369 | |||
3370 | for (redirect = strtok (cpy, " ;"); redirect != NULL; | ||
3371 | redirect = strtok (NULL, " ;")) | ||
3372 | { | ||
3373 | if (NULL == (hostname = strstr (redirect, ":"))) | ||
3374 | { | ||
3375 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3376 | _ ( | ||
3377 | "Option `%s' for domain `%s' is not formatted correctly!\n"), | ||
3378 | redirect, | ||
3379 | name); | ||
3380 | continue; | ||
3381 | } | ||
3382 | hostname[0] = '\0'; | ||
3383 | hostname++; | ||
3384 | if (NULL == (hostport = strstr (hostname, ":"))) | ||
3385 | { | ||
3386 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3387 | _ ( | ||
3388 | "Option `%s' for domain `%s' is not formatted correctly!\n"), | ||
3389 | redirect, | ||
3390 | name); | ||
3391 | continue; | ||
3392 | } | ||
3393 | hostport[0] = '\0'; | ||
3394 | hostport++; | ||
3395 | |||
3396 | int local_port = atoi (redirect); | ||
3397 | int remote_port = atoi (hostport); | ||
3398 | |||
3399 | if (! ((local_port > 0) && (local_port < 65536))) | ||
3400 | { | ||
3401 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3402 | _ ("`%s' is not a valid port number (for domain `%s')!"), | ||
3403 | redirect, | ||
3404 | name); | ||
3405 | continue; | ||
3406 | } | ||
3407 | if (! ((remote_port > 0) && (remote_port < 65536))) | ||
3408 | { | ||
3409 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3410 | _ ("`%s' is not a valid port number (for domain `%s')!"), | ||
3411 | hostport, | ||
3412 | name); | ||
3413 | continue; | ||
3414 | } | ||
3415 | |||
3416 | serv = GNUNET_new (struct LocalService); | ||
3417 | serv->address.proto = proto; | ||
3418 | serv->address.port = remote_port; | ||
3419 | if (0 == strcmp ("localhost4", | ||
3420 | hostname)) | ||
3421 | { | ||
3422 | const char *ip4addr = exit_argv[5]; | ||
3423 | |||
3424 | serv->address.af = AF_INET; | ||
3425 | GNUNET_assert (1 == inet_pton (AF_INET, | ||
3426 | ip4addr, | ||
3427 | &serv->address.address.ipv4)); | ||
3428 | } | ||
3429 | else if (0 == strcmp ("localhost6", | ||
3430 | hostname)) | ||
3431 | { | ||
3432 | const char *ip6addr = exit_argv[3]; | ||
3433 | |||
3434 | serv->address.af = AF_INET6; | ||
3435 | GNUNET_assert (1 == inet_pton (AF_INET6, | ||
3436 | ip6addr, | ||
3437 | &serv->address.address.ipv6)); | ||
3438 | } | ||
3439 | else | ||
3440 | { | ||
3441 | struct addrinfo *res; | ||
3442 | int ret; | ||
3443 | |||
3444 | ret = getaddrinfo (hostname, | ||
3445 | NULL, | ||
3446 | NULL, | ||
3447 | &res); | ||
3448 | if ((0 != ret) || (NULL == res)) | ||
3449 | { | ||
3450 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3451 | _ ( | ||
3452 | "No addresses found for hostname `%s' of service `%s'!\n"), | ||
3453 | hostname, | ||
3454 | n); | ||
3455 | GNUNET_free (serv); | ||
3456 | continue; | ||
3457 | } | ||
3458 | |||
3459 | serv->address.af = res->ai_family; | ||
3460 | switch (res->ai_family) | ||
3461 | { | ||
3462 | case AF_INET: | ||
3463 | if (! ipv4_enabled) | ||
3464 | { | ||
3465 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3466 | _ ( | ||
3467 | "Service `%s' configured for IPv4, but IPv4 is disabled!\n"), | ||
3468 | n); | ||
3469 | freeaddrinfo (res); | ||
3470 | GNUNET_free (serv); | ||
3471 | continue; | ||
3472 | } | ||
3473 | serv->address.address.ipv4 | ||
3474 | = ((struct sockaddr_in *) res->ai_addr)->sin_addr; | ||
3475 | break; | ||
3476 | |||
3477 | case AF_INET6: | ||
3478 | if (! ipv6_enabled) | ||
3479 | { | ||
3480 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3481 | _ ( | ||
3482 | "Service `%s' configured for IPv4, but IPv4 is disabled!\n"), | ||
3483 | n); | ||
3484 | freeaddrinfo (res); | ||
3485 | GNUNET_free (serv); | ||
3486 | continue; | ||
3487 | } | ||
3488 | serv->address.address.ipv6 | ||
3489 | = ((struct sockaddr_in6 *) res->ai_addr)->sin6_addr; | ||
3490 | break; | ||
3491 | |||
3492 | default: | ||
3493 | freeaddrinfo (res); | ||
3494 | GNUNET_log (GNUNET_ERROR_TYPE_WARNING, | ||
3495 | _ ( | ||
3496 | "No IP addresses found for hostname `%s' of service `%s'!\n"), | ||
3497 | hostname, | ||
3498 | n); | ||
3499 | GNUNET_free (serv); | ||
3500 | continue; | ||
3501 | } | ||
3502 | freeaddrinfo (res); | ||
3503 | } | ||
3504 | store_service (proto, | ||
3505 | n, | ||
3506 | local_port, | ||
3507 | serv); | ||
3508 | } | ||
3509 | GNUNET_free (n); | ||
3510 | } | ||
3511 | |||
3512 | |||
3513 | /** | ||
3514 | * Reads the configuration and populates #udp_services and #tcp_services | ||
3515 | * | ||
3516 | * @param cls unused | ||
3517 | * @param section name of section in config | ||
3518 | */ | ||
3519 | static void | ||
3520 | read_service_conf (void *cls, | ||
3521 | const char *section) | ||
3522 | { | ||
3523 | char *cpy; | ||
3524 | |||
3525 | if ((strlen (section) < 8) || | ||
3526 | (0 != strcmp (".gnunet.", section + (strlen (section) - 8)))) | ||
3527 | return; | ||
3528 | if (GNUNET_OK == | ||
3529 | GNUNET_CONFIGURATION_get_value_string (cfg, | ||
3530 | section, | ||
3531 | "UDP_REDIRECTS", | ||
3532 | &cpy)) | ||
3533 | { | ||
3534 | add_services (IPPROTO_UDP, | ||
3535 | cpy, | ||
3536 | section); | ||
3537 | GNUNET_free (cpy); | ||
3538 | } | ||
3539 | if (GNUNET_OK == | ||
3540 | GNUNET_CONFIGURATION_get_value_string (cfg, | ||
3541 | section, | ||
3542 | "TCP_REDIRECTS", | ||
3543 | &cpy)) | ||
3544 | { | ||
3545 | add_services (IPPROTO_TCP, | ||
3546 | cpy, | ||
3547 | section); | ||
3548 | GNUNET_free (cpy); | ||
3549 | } | ||
3550 | } | ||
3551 | |||
3552 | |||
3553 | /** | ||
3554 | * We are running a DNS exit service, advertise it in the | ||
3555 | * DHT. This task is run periodically to do the DHT PUT. | ||
3556 | * | ||
3557 | * @param cls closure | ||
3558 | */ | ||
3559 | static void | ||
3560 | do_dht_put (void *cls); | ||
3561 | |||
3562 | |||
3563 | /** | ||
3564 | * Function called when the DHT PUT operation is complete. | ||
3565 | * Schedules the next PUT. | ||
3566 | * | ||
3567 | * @param cls closure, NULL | ||
3568 | */ | ||
3569 | static void | ||
3570 | dht_put_cont (void *cls) | ||
3571 | { | ||
3572 | dht_put = NULL; | ||
3573 | } | ||
3574 | |||
3575 | |||
3576 | /** | ||
3577 | * We are running a DNS exit service, advertise it in the | ||
3578 | * DHT. This task is run periodically to do the DHT PUT. | ||
3579 | * | ||
3580 | * @param cls closure | ||
3581 | */ | ||
3582 | static void | ||
3583 | do_dht_put (void *cls) | ||
3584 | { | ||
3585 | struct GNUNET_TIME_Absolute expiration; | ||
3586 | |||
3587 | dht_task = GNUNET_SCHEDULER_add_delayed (DHT_PUT_FREQUENCY, | ||
3588 | &do_dht_put, | ||
3589 | NULL); | ||
3590 | expiration = GNUNET_TIME_absolute_ntoh (dns_advertisement.expiration_time); | ||
3591 | if (GNUNET_TIME_absolute_get_remaining (expiration).rel_value_us < | ||
3592 | GNUNET_TIME_UNIT_HOURS.rel_value_us) | ||
3593 | { | ||
3594 | /* refresh advertisement */ | ||
3595 | expiration = GNUNET_TIME_relative_to_absolute (DNS_ADVERTISEMENT_TIMEOUT); | ||
3596 | dns_advertisement.expiration_time = GNUNET_TIME_absolute_hton (expiration); | ||
3597 | GNUNET_assert (GNUNET_OK == | ||
3598 | GNUNET_CRYPTO_eddsa_sign_ (peer_key, | ||
3599 | &dns_advertisement.purpose, | ||
3600 | &dns_advertisement.signature)); | ||
3601 | } | ||
3602 | if (NULL != dht_put) | ||
3603 | GNUNET_DHT_put_cancel (dht_put); | ||
3604 | dht_put = GNUNET_DHT_put (dht, | ||
3605 | &dht_put_key, | ||
3606 | 1 /* replication */, | ||
3607 | GNUNET_DHT_RO_NONE, | ||
3608 | GNUNET_BLOCK_TYPE_DNS, | ||
3609 | sizeof(struct GNUNET_DNS_Advertisement), | ||
3610 | &dns_advertisement, | ||
3611 | expiration, | ||
3612 | &dht_put_cont, | ||
3613 | NULL); | ||
3614 | } | ||
3615 | |||
3616 | |||
3617 | /** | ||
3618 | * Figure out which IP versions we should support (and which | ||
3619 | * are supported by the OS) according to our configuration. | ||
3620 | */ | ||
3621 | static void | ||
3622 | parse_ip_options () | ||
3623 | { | ||
3624 | ipv4_exit = GNUNET_CONFIGURATION_get_value_yesno (cfg, | ||
3625 | "exit", | ||
3626 | "EXIT_IPV4"); | ||
3627 | ipv6_exit = GNUNET_CONFIGURATION_get_value_yesno (cfg, | ||
3628 | "exit", | ||
3629 | "EXIT_IPV6"); | ||
3630 | ipv4_enabled = GNUNET_CONFIGURATION_get_value_yesno (cfg, | ||
3631 | "exit", | ||
3632 | "ENABLE_IPV4"); | ||
3633 | ipv6_enabled = GNUNET_CONFIGURATION_get_value_yesno (cfg, | ||
3634 | "exit", | ||
3635 | "ENABLE_IPV6"); | ||
3636 | if ((ipv4_exit || ipv4_enabled) && | ||
3637 | (GNUNET_OK != GNUNET_NETWORK_test_pf (PF_INET)) ) | ||
3638 | { | ||
3639 | GNUNET_log (GNUNET_ERROR_TYPE_ERROR, | ||
3640 | _ ( | ||
3641 | "This system does not support IPv4, will disable IPv4 functions despite them being enabled in the configuration\n")); | ||
3642 | ipv4_exit = GNUNET_NO; | ||
3643 | ipv4_enabled = GNUNET_NO; | ||
3644 | } | ||
3645 | if ((ipv6_exit || ipv6_enabled) && | ||
3646 | (GNUNET_OK != GNUNET_NETWORK_test_pf (PF_INET6)) ) | ||
3647 | { | ||
3648 | GNUNET_log (GNUNET_ERROR_TYPE_ERROR, | ||
3649 | _ ( | ||
3650 | "This system does not support IPv6, will disable IPv6 functions despite them being enabled in the configuration\n")); | ||
3651 | ipv6_exit = GNUNET_NO; | ||
3652 | ipv6_enabled = GNUNET_NO; | ||
3653 | } | ||
3654 | if (ipv4_exit && (! ipv4_enabled)) | ||
3655 | { | ||
3656 | GNUNET_log (GNUNET_ERROR_TYPE_ERROR, | ||
3657 | _ ( | ||
3658 | "Cannot enable IPv4 exit but disable IPv4 on TUN interface, will use ENABLE_IPv4=YES\n")); | ||
3659 | ipv4_enabled = GNUNET_YES; | ||
3660 | } | ||
3661 | if (ipv6_exit && (! ipv6_enabled)) | ||
3662 | { | ||
3663 | GNUNET_log (GNUNET_ERROR_TYPE_ERROR, | ||
3664 | _ ( | ||
3665 | "Cannot enable IPv6 exit but disable IPv6 on TUN interface, will use ENABLE_IPv6=YES\n")); | ||
3666 | ipv6_enabled = GNUNET_YES; | ||
3667 | } | ||
3668 | } | ||
3669 | |||
3670 | |||
3671 | /** | ||
3672 | * Helper function to open the CADET port for DNS exits and to | ||
3673 | * advertise the DNS exit (if applicable). | ||
3674 | */ | ||
3675 | static void | ||
3676 | advertise_dns_exit () | ||
3677 | { | ||
3678 | struct GNUNET_MQ_MessageHandler handlers[] = { | ||
3679 | GNUNET_MQ_hd_var_size (dns_request, | ||
3680 | GNUNET_MESSAGE_TYPE_VPN_DNS_TO_INTERNET, | ||
3681 | struct DnsResponseMessage, | ||
3682 | NULL), | ||
3683 | GNUNET_MQ_handler_end () | ||
3684 | }; | ||
3685 | char *dns_exit; | ||
3686 | struct GNUNET_HashCode port; | ||
3687 | |||
3688 | if (GNUNET_YES != | ||
3689 | GNUNET_CONFIGURATION_get_value_yesno (cfg, | ||
3690 | "exit", | ||
3691 | "EXIT_DNS")) | ||
3692 | return; | ||
3693 | GNUNET_assert (NULL != (dnsstub = GNUNET_DNSSTUB_start (128))); | ||
3694 | dns_exit = NULL; | ||
3695 | /* TODO: support using multiple DNS resolvers */ | ||
3696 | if ((GNUNET_OK != | ||
3697 | GNUNET_CONFIGURATION_get_value_string (cfg, | ||
3698 | "exit", | ||
3699 | "DNS_RESOLVER", | ||
3700 | &dns_exit)) || | ||
3701 | (GNUNET_OK != | ||
3702 | GNUNET_DNSSTUB_add_dns_ip (dnsstub, | ||
3703 | dns_exit))) | ||
3704 | { | ||
3705 | GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, | ||
3706 | "dns", | ||
3707 | "DNS_RESOLVER", | ||
3708 | _ ("need a valid IPv4 or IPv6 address\n")); | ||
3709 | GNUNET_free (dns_exit); | ||
3710 | return; | ||
3711 | } | ||
3712 | /* open port */ | ||
3713 | GNUNET_CRYPTO_hash (GNUNET_APPLICATION_PORT_INTERNET_RESOLVER, | ||
3714 | strlen (GNUNET_APPLICATION_PORT_INTERNET_RESOLVER), | ||
3715 | &port); | ||
3716 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
3717 | "Opening CADET port %s for DNS exit service\n", | ||
3718 | GNUNET_h2s (&port)); | ||
3719 | dns_port = GNUNET_CADET_open_port (cadet_handle, | ||
3720 | &port, | ||
3721 | &new_channel, | ||
3722 | NULL, | ||
3723 | NULL, | ||
3724 | &clean_channel, | ||
3725 | handlers); | ||
3726 | /* advertise exit */ | ||
3727 | dht = GNUNET_DHT_connect (cfg, | ||
3728 | 1); | ||
3729 | peer_key = GNUNET_CRYPTO_eddsa_key_create_from_configuration (cfg); | ||
3730 | GNUNET_CRYPTO_eddsa_key_get_public (peer_key, | ||
3731 | &dns_advertisement.peer.public_key); | ||
3732 | dns_advertisement.purpose.size = htonl (sizeof(struct | ||
3733 | GNUNET_DNS_Advertisement) | ||
3734 | - sizeof(struct | ||
3735 | GNUNET_CRYPTO_EddsaSignature)); | ||
3736 | dns_advertisement.purpose.purpose = htonl ( | ||
3737 | GNUNET_SIGNATURE_PURPOSE_DNS_RECORD); | ||
3738 | GNUNET_CRYPTO_hash ("dns", | ||
3739 | strlen ("dns"), | ||
3740 | &dht_put_key); | ||
3741 | dht_task = GNUNET_SCHEDULER_add_now (&do_dht_put, | ||
3742 | NULL); | ||
3743 | GNUNET_free (dns_exit); | ||
3744 | } | ||
3745 | |||
3746 | |||
3747 | /** | ||
3748 | * Initialize #exit_argv. | ||
3749 | * | ||
3750 | * @return #GNUNET_OK on success, #GNUNET_SYSERR if we should shutdown | ||
3751 | */ | ||
3752 | static int | ||
3753 | setup_exit_helper_args () | ||
3754 | { | ||
3755 | char *exit_ifname; | ||
3756 | char *tun_ifname; | ||
3757 | char *ipv6addr; | ||
3758 | char *ipv6prefix_s; | ||
3759 | char *ipv4addr; | ||
3760 | char *ipv4mask; | ||
3761 | |||
3762 | exit_argv[0] = GNUNET_strdup ("exit-gnunet"); | ||
3763 | if (GNUNET_SYSERR == | ||
3764 | GNUNET_CONFIGURATION_get_value_string (cfg, | ||
3765 | "exit", | ||
3766 | "TUN_IFNAME", | ||
3767 | &tun_ifname)) | ||
3768 | { | ||
3769 | GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, | ||
3770 | "EXIT", | ||
3771 | "TUN_IFNAME"); | ||
3772 | return GNUNET_SYSERR; | ||
3773 | } | ||
3774 | exit_argv[1] = tun_ifname; | ||
3775 | if (ipv4_enabled) | ||
3776 | { | ||
3777 | if (GNUNET_SYSERR == | ||
3778 | GNUNET_CONFIGURATION_get_value_string (cfg, | ||
3779 | "exit", | ||
3780 | "EXIT_IFNAME", | ||
3781 | &exit_ifname)) | ||
3782 | { | ||
3783 | GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, | ||
3784 | "EXIT", | ||
3785 | "EXIT_IFNAME"); | ||
3786 | return GNUNET_SYSERR; | ||
3787 | } | ||
3788 | exit_argv[2] = exit_ifname; | ||
3789 | } | ||
3790 | else | ||
3791 | { | ||
3792 | exit_argv[2] = GNUNET_strdup ("-"); | ||
3793 | } | ||
3794 | |||
3795 | if (GNUNET_YES == ipv6_enabled) | ||
3796 | { | ||
3797 | ipv6addr = NULL; | ||
3798 | if (((GNUNET_SYSERR == | ||
3799 | GNUNET_CONFIGURATION_get_value_string (cfg, | ||
3800 | "exit", | ||
3801 | "IPV6ADDR", | ||
3802 | &ipv6addr)) || | ||
3803 | (1 != inet_pton (AF_INET6, | ||
3804 | ipv6addr, | ||
3805 | &exit_ipv6addr)))) | ||
3806 | { | ||
3807 | GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, | ||
3808 | "EXIT", | ||
3809 | "IPV6ADDR"); | ||
3810 | GNUNET_free (ipv6addr); | ||
3811 | return GNUNET_SYSERR; | ||
3812 | } | ||
3813 | exit_argv[3] = ipv6addr; | ||
3814 | if (GNUNET_SYSERR == | ||
3815 | GNUNET_CONFIGURATION_get_value_string (cfg, | ||
3816 | "exit", | ||
3817 | "IPV6PREFIX", | ||
3818 | &ipv6prefix_s)) | ||
3819 | { | ||
3820 | GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, | ||
3821 | "EXIT", | ||
3822 | "IPV6PREFIX"); | ||
3823 | return GNUNET_SYSERR; | ||
3824 | } | ||
3825 | exit_argv[4] = ipv6prefix_s; | ||
3826 | if ((GNUNET_OK != | ||
3827 | GNUNET_CONFIGURATION_get_value_number (cfg, | ||
3828 | "exit", | ||
3829 | "IPV6PREFIX", | ||
3830 | &ipv6prefix)) || | ||
3831 | (ipv6prefix >= 127)) | ||
3832 | { | ||
3833 | GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, | ||
3834 | "EXIT", | ||
3835 | "IPV6PREFIX", | ||
3836 | _ ("Must be a number")); | ||
3837 | return GNUNET_SYSERR; | ||
3838 | } | ||
3839 | } | ||
3840 | else | ||
3841 | { | ||
3842 | /* IPv6 explicitly disabled */ | ||
3843 | exit_argv[3] = GNUNET_strdup ("-"); | ||
3844 | exit_argv[4] = GNUNET_strdup ("-"); | ||
3845 | } | ||
3846 | if (GNUNET_YES == ipv4_enabled) | ||
3847 | { | ||
3848 | ipv4addr = NULL; | ||
3849 | if (((GNUNET_SYSERR == | ||
3850 | GNUNET_CONFIGURATION_get_value_string (cfg, | ||
3851 | "exit", | ||
3852 | "IPV4ADDR", | ||
3853 | &ipv4addr)) || | ||
3854 | (1 != inet_pton (AF_INET, | ||
3855 | ipv4addr, | ||
3856 | &exit_ipv4addr)))) | ||
3857 | { | ||
3858 | GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, | ||
3859 | "EXIT", | ||
3860 | "IPV4ADDR"); | ||
3861 | GNUNET_free (ipv4addr); | ||
3862 | return GNUNET_SYSERR; | ||
3863 | } | ||
3864 | exit_argv[5] = ipv4addr; | ||
3865 | ipv4mask = NULL; | ||
3866 | if (((GNUNET_SYSERR == | ||
3867 | GNUNET_CONFIGURATION_get_value_string (cfg, | ||
3868 | "exit", | ||
3869 | "IPV4MASK", | ||
3870 | &ipv4mask)) || | ||
3871 | (1 != inet_pton (AF_INET, | ||
3872 | ipv4mask, | ||
3873 | &exit_ipv4mask)))) | ||
3874 | { | ||
3875 | GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR, | ||
3876 | "EXIT", | ||
3877 | "IPV4MASK"); | ||
3878 | GNUNET_free (ipv4mask); | ||
3879 | return GNUNET_SYSERR; | ||
3880 | } | ||
3881 | exit_argv[6] = ipv4mask; | ||
3882 | } | ||
3883 | else | ||
3884 | { | ||
3885 | /* IPv4 explicitly disabled */ | ||
3886 | exit_argv[5] = GNUNET_strdup ("-"); | ||
3887 | exit_argv[6] = GNUNET_strdup ("-"); | ||
3888 | } | ||
3889 | exit_argv[7] = NULL; | ||
3890 | return GNUNET_OK; | ||
3891 | } | ||
3892 | |||
3893 | |||
3894 | /** | ||
3895 | * @brief Main function that will be run by the scheduler. | ||
3896 | * | ||
3897 | * @param cls closure | ||
3898 | * @param args remaining command-line arguments | ||
3899 | * @param cfgfile name of the configuration file used (for saving, can be NULL!) | ||
3900 | * @param cfg_ configuration | ||
3901 | */ | ||
3902 | static void | ||
3903 | run (void *cls, | ||
3904 | char *const *args, | ||
3905 | const char *cfgfile, | ||
3906 | const struct GNUNET_CONFIGURATION_Handle *cfg_) | ||
3907 | { | ||
3908 | struct GNUNET_MQ_MessageHandler handlers[] = { | ||
3909 | GNUNET_MQ_hd_var_size (icmp_remote, | ||
3910 | GNUNET_MESSAGE_TYPE_VPN_ICMP_TO_INTERNET, | ||
3911 | struct GNUNET_EXIT_IcmpInternetMessage, | ||
3912 | NULL), | ||
3913 | GNUNET_MQ_hd_var_size (udp_remote, | ||
3914 | GNUNET_MESSAGE_TYPE_VPN_UDP_TO_INTERNET, | ||
3915 | struct GNUNET_EXIT_UdpInternetMessage, | ||
3916 | NULL), | ||
3917 | GNUNET_MQ_hd_var_size (tcp_remote, | ||
3918 | GNUNET_MESSAGE_TYPE_VPN_TCP_TO_INTERNET_START, | ||
3919 | struct GNUNET_EXIT_TcpInternetStartMessage, | ||
3920 | NULL), | ||
3921 | GNUNET_MQ_hd_var_size (tcp_data, | ||
3922 | GNUNET_MESSAGE_TYPE_VPN_TCP_DATA_TO_EXIT, | ||
3923 | struct GNUNET_EXIT_TcpDataMessage, | ||
3924 | NULL), | ||
3925 | GNUNET_MQ_handler_end () | ||
3926 | }; | ||
3927 | struct GNUNET_HashCode port; | ||
3928 | char *policy; | ||
3929 | char *binary; | ||
3930 | char *regex; | ||
3931 | char *prefixed_regex; | ||
3932 | |||
3933 | cfg = cfg_; | ||
3934 | if (GNUNET_OK != | ||
3935 | GNUNET_CONFIGURATION_get_value_number (cfg, | ||
3936 | "exit", | ||
3937 | "MAX_CONNECTIONS", | ||
3938 | &max_connections)) | ||
3939 | max_connections = 1024; | ||
3940 | parse_ip_options (); | ||
3941 | binary = GNUNET_OS_get_suid_binary_path (cfg, "gnunet-helper-exit"); | ||
3942 | if ((ipv4_exit) || (ipv6_exit)) | ||
3943 | { | ||
3944 | if (GNUNET_YES != | ||
3945 | GNUNET_OS_check_helper_binary (binary, | ||
3946 | GNUNET_YES, | ||
3947 | "gnunet-vpn - - - 169.1.3.7 255.255.255.0")) // no nat, ipv4 only | ||
3948 | { | ||
3949 | GNUNET_free (binary); | ||
3950 | GNUNET_log (GNUNET_ERROR_TYPE_ERROR, | ||
3951 | _ ( | ||
3952 | "`%s' is not SUID or the path is invalid, EXIT will not work\n"), | ||
3953 | "gnunet-helper-exit"); | ||
3954 | GNUNET_SCHEDULER_add_shutdown (&dummy_task, | ||
3955 | NULL); | ||
3956 | global_ret = 1; | ||
3957 | return; | ||
3958 | } | ||
3959 | } | ||
3960 | if (! (ipv4_enabled || ipv6_enabled)) | ||
3961 | { | ||
3962 | GNUNET_free (binary); | ||
3963 | GNUNET_log (GNUNET_ERROR_TYPE_ERROR, | ||
3964 | _ ("No useful service enabled. Exiting.\n")); | ||
3965 | GNUNET_SCHEDULER_shutdown (); | ||
3966 | return; | ||
3967 | } | ||
3968 | |||
3969 | GNUNET_SCHEDULER_add_shutdown (&cleanup, | ||
3970 | NULL); | ||
3971 | stats = GNUNET_STATISTICS_create ("exit", | ||
3972 | cfg); | ||
3973 | cadet_handle = GNUNET_CADET_connect (cfg); | ||
3974 | if (NULL == cadet_handle) | ||
3975 | { | ||
3976 | GNUNET_free (binary); | ||
3977 | GNUNET_SCHEDULER_shutdown (); | ||
3978 | return; | ||
3979 | } | ||
3980 | advertise_dns_exit (); | ||
3981 | if (GNUNET_OK != | ||
3982 | setup_exit_helper_args ()) | ||
3983 | { | ||
3984 | GNUNET_free (binary); | ||
3985 | GNUNET_SCHEDULER_shutdown (); | ||
3986 | return; | ||
3987 | } | ||
3988 | |||
3989 | services = GNUNET_CONTAINER_multihashmap_create (65536, | ||
3990 | GNUNET_NO); | ||
3991 | connections_map = GNUNET_CONTAINER_multihashmap_create (65536, | ||
3992 | GNUNET_NO); | ||
3993 | connections_heap = GNUNET_CONTAINER_heap_create ( | ||
3994 | GNUNET_CONTAINER_HEAP_ORDER_MIN); | ||
3995 | GNUNET_CONFIGURATION_iterate_sections (cfg, | ||
3996 | &read_service_conf, | ||
3997 | NULL); | ||
3998 | |||
3999 | /* Cadet handle acquired, now open ports and announce regular | ||
4000 | expressions matching our exit */ | ||
4001 | if ((GNUNET_YES == ipv4_enabled) && | ||
4002 | (GNUNET_YES == ipv4_exit)) | ||
4003 | { | ||
4004 | GNUNET_CRYPTO_hash (GNUNET_APPLICATION_PORT_IPV4_GATEWAY, | ||
4005 | strlen (GNUNET_APPLICATION_PORT_IPV4_GATEWAY), | ||
4006 | &port); | ||
4007 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
4008 | "Opening CADET port %s for IPv4 gateway service\n", | ||
4009 | GNUNET_h2s (&port)); | ||
4010 | cadet_port4 = GNUNET_CADET_open_port (cadet_handle, | ||
4011 | &port, | ||
4012 | &new_channel, | ||
4013 | NULL, | ||
4014 | NULL, | ||
4015 | &clean_channel, | ||
4016 | handlers); | ||
4017 | policy = NULL; | ||
4018 | if (GNUNET_OK != | ||
4019 | GNUNET_CONFIGURATION_get_value_string (cfg, | ||
4020 | "exit", | ||
4021 | "EXIT_RANGE_IPV4_POLICY", | ||
4022 | &policy)) | ||
4023 | regex = NULL; | ||
4024 | else | ||
4025 | regex = GNUNET_TUN_ipv4policy2regex (policy); | ||
4026 | GNUNET_free (policy); | ||
4027 | if (NULL != regex) | ||
4028 | { | ||
4029 | (void) GNUNET_asprintf (&prefixed_regex, | ||
4030 | "%s%s", | ||
4031 | GNUNET_APPLICATION_TYPE_EXIT_REGEX_PREFIX, | ||
4032 | regex); | ||
4033 | regex4 = GNUNET_REGEX_announce (cfg, | ||
4034 | prefixed_regex, | ||
4035 | REGEX_REFRESH_FREQUENCY, | ||
4036 | REGEX_MAX_PATH_LEN_IPV4); | ||
4037 | GNUNET_free (regex); | ||
4038 | GNUNET_free (prefixed_regex); | ||
4039 | } | ||
4040 | } | ||
4041 | |||
4042 | if ((GNUNET_YES == ipv6_enabled) && (GNUNET_YES == ipv6_exit)) | ||
4043 | { | ||
4044 | GNUNET_CRYPTO_hash (GNUNET_APPLICATION_PORT_IPV6_GATEWAY, | ||
4045 | strlen (GNUNET_APPLICATION_PORT_IPV6_GATEWAY), | ||
4046 | &port); | ||
4047 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
4048 | "Opening CADET port %s for IPv6 gateway service\n", | ||
4049 | GNUNET_h2s (&port)); | ||
4050 | cadet_port6 = GNUNET_CADET_open_port (cadet_handle, | ||
4051 | &port, | ||
4052 | &new_channel, | ||
4053 | NULL, | ||
4054 | NULL, | ||
4055 | &clean_channel, | ||
4056 | handlers); | ||
4057 | policy = NULL; | ||
4058 | if (GNUNET_OK != | ||
4059 | GNUNET_CONFIGURATION_get_value_string (cfg, | ||
4060 | "exit", | ||
4061 | "EXIT_RANGE_IPV6_POLICY", | ||
4062 | &policy)) | ||
4063 | regex = NULL; | ||
4064 | else | ||
4065 | regex = GNUNET_TUN_ipv6policy2regex (policy); | ||
4066 | GNUNET_free (policy); | ||
4067 | if (NULL != regex) | ||
4068 | { | ||
4069 | (void) GNUNET_asprintf (&prefixed_regex, | ||
4070 | "%s%s", | ||
4071 | GNUNET_APPLICATION_TYPE_EXIT_REGEX_PREFIX, | ||
4072 | regex); | ||
4073 | regex6 = GNUNET_REGEX_announce (cfg, | ||
4074 | prefixed_regex, | ||
4075 | REGEX_REFRESH_FREQUENCY, | ||
4076 | REGEX_MAX_PATH_LEN_IPV6); | ||
4077 | GNUNET_free (regex); | ||
4078 | GNUNET_free (prefixed_regex); | ||
4079 | } | ||
4080 | } | ||
4081 | helper_handle = GNUNET_HELPER_start (GNUNET_NO, | ||
4082 | binary, | ||
4083 | exit_argv, | ||
4084 | &message_token, | ||
4085 | NULL, | ||
4086 | NULL); | ||
4087 | GNUNET_free (binary); | ||
4088 | } | ||
4089 | |||
4090 | |||
4091 | /** | ||
4092 | * The main function | ||
4093 | * | ||
4094 | * @param argc number of arguments from the command line | ||
4095 | * @param argv command line arguments | ||
4096 | * @return 0 ok, 1 on error | ||
4097 | */ | ||
4098 | int | ||
4099 | main (int argc, | ||
4100 | char *const *argv) | ||
4101 | { | ||
4102 | static const struct GNUNET_GETOPT_CommandLineOption options[] = { | ||
4103 | GNUNET_GETOPT_OPTION_END | ||
4104 | }; | ||
4105 | |||
4106 | if (GNUNET_OK != | ||
4107 | GNUNET_STRINGS_get_utf8_args (argc, | ||
4108 | argv, | ||
4109 | &argc, | ||
4110 | &argv)) | ||
4111 | return 2; | ||
4112 | |||
4113 | return (GNUNET_OK == | ||
4114 | GNUNET_PROGRAM_run (argc, | ||
4115 | argv, | ||
4116 | "gnunet-daemon-exit", | ||
4117 | gettext_noop ( | ||
4118 | "Daemon to run to provide an IP exit node for the VPN"), | ||
4119 | options, | ||
4120 | &run, | ||
4121 | NULL)) ? global_ret : 1; | ||
4122 | } | ||
4123 | |||
4124 | |||
4125 | /* end of gnunet-daemon-exit.c */ | ||
diff --git a/src/exit/gnunet-helper-exit.c b/src/exit/gnunet-helper-exit.c deleted file mode 100644 index 4f32ea1f1..000000000 --- a/src/exit/gnunet-helper-exit.c +++ /dev/null | |||
@@ -1,859 +0,0 @@ | |||
1 | /* | ||
2 | This file is part of GNUnet. | ||
3 | Copyright (C) 2010, 2011, 2012 Christian Grothoff | ||
4 | |||
5 | GNUnet is free software: you can redistribute it and/or modify it | ||
6 | under the terms of the GNU Affero General Public License as published | ||
7 | by the Free Software Foundation, either version 3 of the License, | ||
8 | or (at your option) any later version. | ||
9 | |||
10 | GNUnet is distributed in the hope that it will be useful, but | ||
11 | WITHOUT ANY WARRANTY; without even the implied warranty of | ||
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
13 | Affero General Public License for more details. | ||
14 | |||
15 | You should have received a copy of the GNU Affero General Public License | ||
16 | along with this program. If not, see <http://www.gnu.org/licenses/>. | ||
17 | |||
18 | SPDX-License-Identifier: AGPL3.0-or-later | ||
19 | */ | ||
20 | |||
21 | /** | ||
22 | * @file exit/gnunet-helper-exit.c | ||
23 | * | ||
24 | * @brief the helper for exit nodes. Opens a virtual | ||
25 | * network-interface, sends data received on the if to stdout, sends | ||
26 | * data received on stdin to the interface. The code also enables | ||
27 | * IPv4/IPv6 forwarding and NAT on the current system (the latter on | ||
28 | * an interface specified on the command-line); these changes to the | ||
29 | * network configuration are NOT automatically undone when the program | ||
30 | * is stopped (this is because we cannot be sure that some other | ||
31 | * application didn't enable them before or after us; also, these | ||
32 | * changes should be mostly harmless as it simply turns the system | ||
33 | * into a router). | ||
34 | * | ||
35 | * @author Philipp Tölke | ||
36 | * @author Christian Grothoff | ||
37 | * | ||
38 | * The following list of people have reviewed this code and considered | ||
39 | * it safe since the last modification (if you reviewed it, please | ||
40 | * have your name added to the list): | ||
41 | * | ||
42 | * - Philipp Tölke | ||
43 | */ | ||
44 | #include "platform.h" | ||
45 | |||
46 | #ifdef IF_TUN_HDR | ||
47 | #include IF_TUN_HDR | ||
48 | #endif | ||
49 | |||
50 | #if defined(BSD) || defined(SOLARIS) | ||
51 | #define ifr_netmask ifr_ifru.ifru_addr | ||
52 | #define SIOGIFINDEX SIOCGIFINDEX | ||
53 | #endif | ||
54 | |||
55 | /** | ||
56 | * Need 'struct GNUNET_MessageHeader'. | ||
57 | */ | ||
58 | #include "gnunet_crypto_lib.h" | ||
59 | #include "gnunet_common.h" | ||
60 | |||
61 | /** | ||
62 | * Need VPN message types. | ||
63 | */ | ||
64 | #include "gnunet_protocols.h" | ||
65 | |||
66 | /** | ||
67 | * Should we print (interesting|debug) messages that can happen during | ||
68 | * normal operation? | ||
69 | */ | ||
70 | #define DEBUG GNUNET_NO | ||
71 | |||
72 | /** | ||
73 | * Maximum size of a GNUnet message (GNUNET_MAX_MESSAGE_SIZE) | ||
74 | */ | ||
75 | #define MAX_SIZE 65536 | ||
76 | |||
77 | /** | ||
78 | * Path to 'sysctl' binary. | ||
79 | */ | ||
80 | static const char *sbin_sysctl; | ||
81 | |||
82 | /** | ||
83 | * Path to 'iptables' binary. | ||
84 | */ | ||
85 | static const char *sbin_iptables; | ||
86 | |||
87 | |||
88 | #if ! defined(__ANDROID__) | ||
89 | #if ! defined(_LINUX_IN6_H) && defined(__linux__) | ||
90 | /** | ||
91 | * This is in linux/include/net/ipv6.h, but not always exported. | ||
92 | */ | ||
93 | struct in6_ifreq | ||
94 | { | ||
95 | struct in6_addr ifr6_addr; | ||
96 | uint32_t ifr6_prefixlen; /* __u32 in the original */ | ||
97 | int ifr6_ifindex; | ||
98 | }; | ||
99 | #endif | ||
100 | #endif | ||
101 | |||
102 | |||
103 | /** | ||
104 | * Open '/dev/null' and make the result the given | ||
105 | * file descriptor. | ||
106 | * | ||
107 | * @param target_fd desired FD to point to /dev/null | ||
108 | * @param flags open flags (O_RDONLY, O_WRONLY) | ||
109 | */ | ||
110 | static void | ||
111 | open_dev_null (int target_fd, | ||
112 | int flags) | ||
113 | { | ||
114 | int fd; | ||
115 | |||
116 | fd = open ("/dev/null", flags); | ||
117 | if (-1 == fd) | ||
118 | abort (); | ||
119 | if (fd == target_fd) | ||
120 | return; | ||
121 | if (-1 == dup2 (fd, target_fd)) | ||
122 | { | ||
123 | (void) close (fd); | ||
124 | abort (); | ||
125 | } | ||
126 | (void) close (fd); | ||
127 | } | ||
128 | |||
129 | |||
130 | /** | ||
131 | * Run the given command and wait for it to complete. | ||
132 | * | ||
133 | * @param file name of the binary to run | ||
134 | * @param cmd command line arguments (as given to 'execv') | ||
135 | * @return 0 on success, 1 on any error | ||
136 | */ | ||
137 | static int | ||
138 | fork_and_exec (const char *file, | ||
139 | char *const cmd[]) | ||
140 | { | ||
141 | int status; | ||
142 | pid_t pid; | ||
143 | pid_t ret; | ||
144 | |||
145 | pid = fork (); | ||
146 | if (-1 == pid) | ||
147 | { | ||
148 | fprintf (stderr, | ||
149 | "fork failed: %s\n", | ||
150 | strerror (errno)); | ||
151 | return 1; | ||
152 | } | ||
153 | if (0 == pid) | ||
154 | { | ||
155 | /* we are the child process */ | ||
156 | /* close stdin/stdout to not cause interference | ||
157 | with the helper's main protocol! */ | ||
158 | (void) close (0); | ||
159 | open_dev_null (0, O_RDONLY); | ||
160 | (void) close (1); | ||
161 | open_dev_null (1, O_WRONLY); | ||
162 | (void) execv (file, cmd); | ||
163 | /* can only get here on error */ | ||
164 | fprintf (stderr, | ||
165 | "exec `%s' failed: %s\n", | ||
166 | file, | ||
167 | strerror (errno)); | ||
168 | _exit (1); | ||
169 | } | ||
170 | /* keep running waitpid as long as the only error we get is 'EINTR' */ | ||
171 | while ((-1 == (ret = waitpid (pid, &status, 0))) && | ||
172 | (errno == EINTR)) | ||
173 | ; | ||
174 | if (-1 == ret) | ||
175 | { | ||
176 | fprintf (stderr, | ||
177 | "waitpid failed: %s\n", | ||
178 | strerror (errno)); | ||
179 | return 1; | ||
180 | } | ||
181 | if (! (WIFEXITED (status) && (0 == WEXITSTATUS (status)))) | ||
182 | return 1; | ||
183 | /* child process completed and returned success, we're happy */ | ||
184 | return 0; | ||
185 | } | ||
186 | |||
187 | |||
188 | /** | ||
189 | * Creates a tun-interface called dev; | ||
190 | * | ||
191 | * @param dev is assumed to point to a char[IFNAMSIZ] | ||
192 | * if *dev == '\\0', uses the name supplied by the kernel; | ||
193 | * @return the fd to the tun or -1 on error | ||
194 | */ | ||
195 | #ifdef IFF_TUN /* LINUX */ | ||
196 | static int | ||
197 | init_tun (char *dev) | ||
198 | { | ||
199 | struct ifreq ifr; | ||
200 | int fd; | ||
201 | |||
202 | if (NULL == dev) | ||
203 | { | ||
204 | errno = EINVAL; | ||
205 | return -1; | ||
206 | } | ||
207 | |||
208 | if (-1 == (fd = open ("/dev/net/tun", O_RDWR))) | ||
209 | { | ||
210 | fprintf (stderr, "Error opening `%s': %s\n", "/dev/net/tun", | ||
211 | strerror (errno)); | ||
212 | return -1; | ||
213 | } | ||
214 | |||
215 | if (fd >= FD_SETSIZE) | ||
216 | { | ||
217 | fprintf (stderr, "File descriptor to large: %d", fd); | ||
218 | (void) close (fd); | ||
219 | return -1; | ||
220 | } | ||
221 | |||
222 | memset (&ifr, 0, sizeof(ifr)); | ||
223 | ifr.ifr_flags = IFF_TUN; | ||
224 | |||
225 | if ('\0' != *dev) | ||
226 | strncpy (ifr.ifr_name, dev, IFNAMSIZ); | ||
227 | |||
228 | if (-1 == ioctl (fd, TUNSETIFF, (void *) &ifr)) | ||
229 | { | ||
230 | fprintf (stderr, | ||
231 | "Error with ioctl on `%s': %s\n", "/dev/net/tun", | ||
232 | strerror (errno)); | ||
233 | (void) close (fd); | ||
234 | return -1; | ||
235 | } | ||
236 | strcpy (dev, ifr.ifr_name); | ||
237 | return fd; | ||
238 | } | ||
239 | |||
240 | |||
241 | #else /* BSD et al, including DARWIN */ | ||
242 | |||
243 | #ifdef SIOCIFCREATE | ||
244 | static int | ||
245 | init_tun (char *dev) | ||
246 | { | ||
247 | int fd; | ||
248 | int s; | ||
249 | struct ifreq ifr; | ||
250 | |||
251 | fd = open (dev, O_RDWR); | ||
252 | if (fd == -1) | ||
253 | { | ||
254 | s = socket (AF_INET, SOCK_DGRAM, 0); | ||
255 | if (s < 0) | ||
256 | return -1; | ||
257 | memset (&ifr, 0, sizeof(ifr)); | ||
258 | strncpy (ifr.ifr_name, dev + 5, sizeof(ifr.ifr_name) - 1); | ||
259 | if (! ioctl (s, SIOCIFCREATE, &ifr)) | ||
260 | fd = open (dev, O_RDWR); | ||
261 | close (s); | ||
262 | } | ||
263 | return fd; | ||
264 | } | ||
265 | |||
266 | |||
267 | #else | ||
268 | #define init_tun(dev) open (dev, O_RDWR) | ||
269 | #endif | ||
270 | #endif /* !IFF_TUN (BSD) */ | ||
271 | |||
272 | /** | ||
273 | * @brief Sets the IPv6-Address given in address on the interface dev | ||
274 | * | ||
275 | * @param dev the interface to configure | ||
276 | * @param address the IPv6-Address | ||
277 | * @param prefix_len the length of the network-prefix | ||
278 | */ | ||
279 | static void | ||
280 | set_address6 (const char *dev, const char *address, unsigned long prefix_len) | ||
281 | { | ||
282 | struct ifreq ifr; | ||
283 | struct sockaddr_in6 sa6; | ||
284 | int fd; | ||
285 | struct in6_ifreq ifr6; | ||
286 | |||
287 | /* | ||
288 | * parse the new address | ||
289 | */ | ||
290 | memset (&sa6, 0, sizeof(struct sockaddr_in6)); | ||
291 | sa6.sin6_family = AF_INET6; | ||
292 | if (1 != inet_pton (AF_INET6, address, &sa6.sin6_addr)) | ||
293 | { | ||
294 | fprintf (stderr, "Failed to parse address `%s': %s\n", address, | ||
295 | strerror (errno)); | ||
296 | exit (1); | ||
297 | } | ||
298 | |||
299 | if (-1 == (fd = socket (PF_INET6, SOCK_DGRAM, 0))) | ||
300 | { | ||
301 | fprintf (stderr, "Error creating socket: %s\n", strerror (errno)); | ||
302 | exit (1); | ||
303 | } | ||
304 | |||
305 | memset (&ifr, 0, sizeof(struct ifreq)); | ||
306 | /* | ||
307 | * Get the index of the if | ||
308 | */ | ||
309 | strncpy (ifr.ifr_name, dev, IFNAMSIZ); | ||
310 | if (-1 == ioctl (fd, SIOGIFINDEX, &ifr)) | ||
311 | { | ||
312 | fprintf (stderr, "ioctl failed at %d: %s\n", __LINE__, strerror (errno)); | ||
313 | (void) close (fd); | ||
314 | exit (1); | ||
315 | } | ||
316 | |||
317 | memset (&ifr6, 0, sizeof(struct in6_ifreq)); | ||
318 | ifr6.ifr6_addr = sa6.sin6_addr; | ||
319 | ifr6.ifr6_ifindex = ifr.ifr_ifindex; | ||
320 | ifr6.ifr6_prefixlen = prefix_len; | ||
321 | |||
322 | /* | ||
323 | * Set the address | ||
324 | */ | ||
325 | if (-1 == ioctl (fd, SIOCSIFADDR, &ifr6)) | ||
326 | { | ||
327 | fprintf (stderr, "ioctl failed at line %d: %s\n", __LINE__, | ||
328 | strerror (errno)); | ||
329 | (void) close (fd); | ||
330 | exit (1); | ||
331 | } | ||
332 | |||
333 | /* | ||
334 | * Get the flags | ||
335 | */ | ||
336 | if (-1 == ioctl (fd, SIOCGIFFLAGS, &ifr)) | ||
337 | { | ||
338 | fprintf (stderr, "ioctl failed at line %d: %s\n", __LINE__, | ||
339 | strerror (errno)); | ||
340 | (void) close (fd); | ||
341 | exit (1); | ||
342 | } | ||
343 | |||
344 | /* | ||
345 | * Add the UP and RUNNING flags | ||
346 | */ | ||
347 | ifr.ifr_flags |= IFF_UP | IFF_RUNNING; | ||
348 | if (-1 == ioctl (fd, SIOCSIFFLAGS, &ifr)) | ||
349 | { | ||
350 | fprintf (stderr, "ioctl failed at line %d: %s\n", __LINE__, | ||
351 | strerror (errno)); | ||
352 | (void) close (fd); | ||
353 | exit (1); | ||
354 | } | ||
355 | |||
356 | if (0 != close (fd)) | ||
357 | { | ||
358 | fprintf (stderr, "close failed: %s\n", strerror (errno)); | ||
359 | exit (1); | ||
360 | } | ||
361 | } | ||
362 | |||
363 | |||
364 | /** | ||
365 | * @brief Sets the IPv4-Address given in address on the interface dev | ||
366 | * | ||
367 | * @param dev the interface to configure | ||
368 | * @param address the IPv4-Address | ||
369 | * @param mask the netmask | ||
370 | */ | ||
371 | static void | ||
372 | set_address4 (const char *dev, const char *address, const char *mask) | ||
373 | { | ||
374 | int fd; | ||
375 | struct sockaddr_in *addr; | ||
376 | struct ifreq ifr; | ||
377 | |||
378 | memset (&ifr, 0, sizeof(struct ifreq)); | ||
379 | addr = (struct sockaddr_in *) &(ifr.ifr_addr); | ||
380 | addr->sin_family = AF_INET; | ||
381 | |||
382 | /* | ||
383 | * Parse the address | ||
384 | */ | ||
385 | if (1 != inet_pton (AF_INET, address, &addr->sin_addr.s_addr)) | ||
386 | { | ||
387 | fprintf (stderr, "Failed to parse address `%s': %s\n", address, | ||
388 | strerror (errno)); | ||
389 | exit (1); | ||
390 | } | ||
391 | |||
392 | if (-1 == (fd = socket (PF_INET, SOCK_DGRAM, 0))) | ||
393 | { | ||
394 | fprintf (stderr, "Error creating socket: %s\n", strerror (errno)); | ||
395 | exit (1); | ||
396 | } | ||
397 | |||
398 | strncpy (ifr.ifr_name, dev, IFNAMSIZ); | ||
399 | |||
400 | /* | ||
401 | * Set the address | ||
402 | */ | ||
403 | if (-1 == ioctl (fd, SIOCSIFADDR, &ifr)) | ||
404 | { | ||
405 | fprintf (stderr, "ioctl failed at %d: %s\n", __LINE__, strerror (errno)); | ||
406 | (void) close (fd); | ||
407 | exit (1); | ||
408 | } | ||
409 | |||
410 | /* | ||
411 | * Parse the netmask | ||
412 | */ | ||
413 | addr = (struct sockaddr_in *) &(ifr.ifr_netmask); | ||
414 | if (1 != inet_pton (AF_INET, mask, &addr->sin_addr.s_addr)) | ||
415 | { | ||
416 | fprintf (stderr, "Failed to parse address `%s': %s\n", mask, | ||
417 | strerror (errno)); | ||
418 | (void) close (fd); | ||
419 | exit (1); | ||
420 | } | ||
421 | |||
422 | /* | ||
423 | * Set the netmask | ||
424 | */ | ||
425 | if (-1 == ioctl (fd, SIOCSIFNETMASK, &ifr)) | ||
426 | { | ||
427 | fprintf (stderr, "ioctl failed at line %d: %s\n", __LINE__, | ||
428 | strerror (errno)); | ||
429 | (void) close (fd); | ||
430 | exit (1); | ||
431 | } | ||
432 | |||
433 | /* | ||
434 | * Get the flags | ||
435 | */ | ||
436 | if (-1 == ioctl (fd, SIOCGIFFLAGS, &ifr)) | ||
437 | { | ||
438 | fprintf (stderr, "ioctl failed at line %d: %s\n", __LINE__, | ||
439 | strerror (errno)); | ||
440 | (void) close (fd); | ||
441 | exit (1); | ||
442 | } | ||
443 | |||
444 | /* | ||
445 | * Add the UP and RUNNING flags | ||
446 | */ | ||
447 | ifr.ifr_flags |= IFF_UP | IFF_RUNNING; | ||
448 | if (-1 == ioctl (fd, SIOCSIFFLAGS, &ifr)) | ||
449 | { | ||
450 | fprintf (stderr, "ioctl failed at line %d: %s\n", __LINE__, | ||
451 | strerror (errno)); | ||
452 | (void) close (fd); | ||
453 | exit (1); | ||
454 | } | ||
455 | |||
456 | if (0 != close (fd)) | ||
457 | { | ||
458 | fprintf (stderr, "close failed: %s\n", strerror (errno)); | ||
459 | (void) close (fd); | ||
460 | exit (1); | ||
461 | } | ||
462 | } | ||
463 | |||
464 | |||
465 | /** | ||
466 | * Start forwarding to and from the tunnel. | ||
467 | * | ||
468 | * @param fd_tun tunnel FD | ||
469 | */ | ||
470 | static void | ||
471 | run (int fd_tun) | ||
472 | { | ||
473 | /* | ||
474 | * The buffer filled by reading from fd_tun | ||
475 | */ | ||
476 | unsigned char buftun[MAX_SIZE]; | ||
477 | ssize_t buftun_size = 0; | ||
478 | unsigned char *buftun_read = NULL; | ||
479 | |||
480 | /* | ||
481 | * The buffer filled by reading from stdin | ||
482 | */ | ||
483 | unsigned char bufin[MAX_SIZE]; | ||
484 | ssize_t bufin_size = 0; | ||
485 | size_t bufin_rpos = 0; | ||
486 | unsigned char *bufin_read = NULL; | ||
487 | |||
488 | fd_set fds_w; | ||
489 | fd_set fds_r; | ||
490 | |||
491 | /* read refers to reading from fd_tun, writing to stdout */ | ||
492 | int read_open = 1; | ||
493 | |||
494 | /* write refers to reading from stdin, writing to fd_tun */ | ||
495 | int write_open = 1; | ||
496 | |||
497 | while ((1 == read_open) && (1 == write_open)) | ||
498 | { | ||
499 | FD_ZERO (&fds_w); | ||
500 | FD_ZERO (&fds_r); | ||
501 | |||
502 | /* | ||
503 | * We are supposed to read and the buffer is empty | ||
504 | * -> select on read from tun | ||
505 | */ | ||
506 | if (read_open && (0 == buftun_size)) | ||
507 | FD_SET (fd_tun, &fds_r); | ||
508 | |||
509 | /* | ||
510 | * We are supposed to read and the buffer is not empty | ||
511 | * -> select on write to stdout | ||
512 | */ | ||
513 | if (read_open && (0 != buftun_size)) | ||
514 | FD_SET (1, &fds_w); | ||
515 | |||
516 | /* | ||
517 | * We are supposed to write and the buffer is empty | ||
518 | * -> select on read from stdin | ||
519 | */ | ||
520 | if (write_open && (NULL == bufin_read)) | ||
521 | FD_SET (0, &fds_r); | ||
522 | |||
523 | /* | ||
524 | * We are supposed to write and the buffer is not empty | ||
525 | * -> select on write to tun | ||
526 | */ | ||
527 | if (write_open && (NULL != bufin_read)) | ||
528 | FD_SET (fd_tun, &fds_w); | ||
529 | |||
530 | int r = select (fd_tun + 1, &fds_r, &fds_w, NULL, NULL); | ||
531 | |||
532 | if (-1 == r) | ||
533 | { | ||
534 | if (EINTR == errno) | ||
535 | continue; | ||
536 | fprintf (stderr, "select failed: %s\n", strerror (errno)); | ||
537 | exit (1); | ||
538 | } | ||
539 | |||
540 | if (r > 0) | ||
541 | { | ||
542 | if (FD_ISSET (fd_tun, &fds_r)) | ||
543 | { | ||
544 | buftun_size = | ||
545 | read (fd_tun, buftun + sizeof(struct GNUNET_MessageHeader), | ||
546 | MAX_SIZE - sizeof(struct GNUNET_MessageHeader)); | ||
547 | if (-1 == buftun_size) | ||
548 | { | ||
549 | fprintf (stderr, | ||
550 | "read-error: %s\n", | ||
551 | strerror (errno)); | ||
552 | shutdown (fd_tun, SHUT_RD); | ||
553 | shutdown (1, SHUT_WR); | ||
554 | read_open = 0; | ||
555 | buftun_size = 0; | ||
556 | } | ||
557 | else if (0 == buftun_size) | ||
558 | { | ||
559 | #if DEBUG | ||
560 | fprintf (stderr, "EOF on tun\n"); | ||
561 | #endif | ||
562 | shutdown (fd_tun, SHUT_RD); | ||
563 | shutdown (1, SHUT_WR); | ||
564 | read_open = 0; | ||
565 | buftun_size = 0; | ||
566 | } | ||
567 | else | ||
568 | { | ||
569 | buftun_read = buftun; | ||
570 | struct GNUNET_MessageHeader *hdr = | ||
571 | (struct GNUNET_MessageHeader *) buftun; | ||
572 | buftun_size += sizeof(struct GNUNET_MessageHeader); | ||
573 | hdr->type = htons (GNUNET_MESSAGE_TYPE_VPN_HELPER); | ||
574 | hdr->size = htons (buftun_size); | ||
575 | } | ||
576 | } | ||
577 | else if (FD_ISSET (1, &fds_w)) | ||
578 | { | ||
579 | ssize_t written = write (1, buftun_read, buftun_size); | ||
580 | |||
581 | if (-1 == written) | ||
582 | { | ||
583 | #if ! DEBUG | ||
584 | if (errno != EPIPE) | ||
585 | #endif | ||
586 | fprintf (stderr, | ||
587 | "write-error to stdout: %s\n", | ||
588 | strerror (errno)); | ||
589 | shutdown (fd_tun, SHUT_RD); | ||
590 | shutdown (1, SHUT_WR); | ||
591 | read_open = 0; | ||
592 | buftun_size = 0; | ||
593 | } | ||
594 | else if (0 == written) | ||
595 | { | ||
596 | fprintf (stderr, "write returned 0!?\n"); | ||
597 | exit (1); | ||
598 | } | ||
599 | else | ||
600 | { | ||
601 | buftun_size -= written; | ||
602 | buftun_read += written; | ||
603 | } | ||
604 | } | ||
605 | |||
606 | if (FD_ISSET (0, &fds_r)) | ||
607 | { | ||
608 | bufin_size = read (0, bufin + bufin_rpos, MAX_SIZE - bufin_rpos); | ||
609 | if (-1 == bufin_size) | ||
610 | { | ||
611 | fprintf (stderr, "read-error: %s\n", strerror (errno)); | ||
612 | shutdown (0, SHUT_RD); | ||
613 | shutdown (fd_tun, SHUT_WR); | ||
614 | write_open = 0; | ||
615 | bufin_size = 0; | ||
616 | } | ||
617 | else if (0 == bufin_size) | ||
618 | { | ||
619 | #if DEBUG | ||
620 | fprintf (stderr, "EOF on stdin\n"); | ||
621 | #endif | ||
622 | shutdown (0, SHUT_RD); | ||
623 | shutdown (fd_tun, SHUT_WR); | ||
624 | write_open = 0; | ||
625 | bufin_size = 0; | ||
626 | } | ||
627 | else | ||
628 | { | ||
629 | struct GNUNET_MessageHeader *hdr; | ||
630 | |||
631 | PROCESS_BUFFER: | ||
632 | bufin_rpos += bufin_size; | ||
633 | if (bufin_rpos < sizeof(struct GNUNET_MessageHeader)) | ||
634 | continue; | ||
635 | hdr = (struct GNUNET_MessageHeader *) bufin; | ||
636 | if (ntohs (hdr->type) != GNUNET_MESSAGE_TYPE_VPN_HELPER) | ||
637 | { | ||
638 | fprintf (stderr, "protocol violation!\n"); | ||
639 | exit (1); | ||
640 | } | ||
641 | if (ntohs (hdr->size) > bufin_rpos) | ||
642 | continue; | ||
643 | bufin_read = bufin + sizeof(struct GNUNET_MessageHeader); | ||
644 | bufin_size = ntohs (hdr->size) - sizeof(struct GNUNET_MessageHeader); | ||
645 | bufin_rpos -= bufin_size + sizeof(struct GNUNET_MessageHeader); | ||
646 | } | ||
647 | } | ||
648 | else if (FD_ISSET (fd_tun, &fds_w)) | ||
649 | { | ||
650 | ssize_t written = write (fd_tun, bufin_read, bufin_size); | ||
651 | |||
652 | if (-1 == written) | ||
653 | { | ||
654 | fprintf (stderr, "write-error to tun: %s\n", strerror (errno)); | ||
655 | shutdown (0, SHUT_RD); | ||
656 | shutdown (fd_tun, SHUT_WR); | ||
657 | write_open = 0; | ||
658 | bufin_size = 0; | ||
659 | } | ||
660 | else if (0 == written) | ||
661 | { | ||
662 | fprintf (stderr, "write returned 0!?\n"); | ||
663 | exit (1); | ||
664 | } | ||
665 | else | ||
666 | { | ||
667 | bufin_size -= written; | ||
668 | bufin_read += written; | ||
669 | if (0 == bufin_size) | ||
670 | { | ||
671 | memmove (bufin, bufin_read, bufin_rpos); | ||
672 | bufin_read = NULL; /* start reading again */ | ||
673 | bufin_size = 0; | ||
674 | goto PROCESS_BUFFER; | ||
675 | } | ||
676 | } | ||
677 | } | ||
678 | } | ||
679 | } | ||
680 | } | ||
681 | |||
682 | |||
683 | /** | ||
684 | * Open VPN tunnel interface. | ||
685 | * | ||
686 | * @param argc must be 6 | ||
687 | * @param argv 0: binary name ("gnunet-helper-exit") | ||
688 | * 1: tunnel interface name ("gnunet-exit") | ||
689 | * 2: "physical" interface name ("eth0"), or "-" to not setup NAT | ||
690 | * and routing | ||
691 | * 3: IPv6 address ("::1"), or "-" to skip IPv6 | ||
692 | * 4: IPv6 netmask length in bits ("64") [ignored if #4 is "-"] | ||
693 | * 5: IPv4 address ("1.2.3.4"), or "-" to skip IPv4 | ||
694 | * 6: IPv4 netmask ("255.255.0.0") [ignored if #4 is "-"] | ||
695 | */ | ||
696 | int | ||
697 | main (int argc, char **argv) | ||
698 | { | ||
699 | char dev[IFNAMSIZ]; | ||
700 | int fd_tun; | ||
701 | int global_ret; | ||
702 | |||
703 | if (7 != argc) | ||
704 | { | ||
705 | fprintf (stderr, "Fatal: must supply 6 arguments!\n"); | ||
706 | return 1; | ||
707 | } | ||
708 | if ((0 == strcmp (argv[3], "-")) && | ||
709 | (0 == strcmp (argv[5], "-"))) | ||
710 | { | ||
711 | fprintf (stderr, "Fatal: disabling both IPv4 and IPv6 makes no sense.\n"); | ||
712 | return 1; | ||
713 | } | ||
714 | if (0 != strcmp (argv[2], "-")) | ||
715 | { | ||
716 | #ifdef IPTABLES | ||
717 | if (0 == access (IPTABLES, X_OK)) | ||
718 | sbin_iptables = IPTABLES; | ||
719 | else | ||
720 | #endif | ||
721 | if (0 == access ("/sbin/iptables", X_OK)) | ||
722 | sbin_iptables = "/sbin/iptables"; | ||
723 | else if (0 == access ("/usr/sbin/iptables", X_OK)) | ||
724 | sbin_iptables = "/usr/sbin/iptables"; | ||
725 | else | ||
726 | { | ||
727 | fprintf (stderr, | ||
728 | "Fatal: executable iptables not found in approved directories: %s\n", | ||
729 | strerror (errno)); | ||
730 | return 1; | ||
731 | } | ||
732 | #ifdef SYSCTL | ||
733 | if (0 == access (SYSCTL, X_OK)) | ||
734 | sbin_sysctl = SYSCTL; | ||
735 | else | ||
736 | #endif | ||
737 | if (0 == access ("/sbin/sysctl", X_OK)) | ||
738 | sbin_sysctl = "/sbin/sysctl"; | ||
739 | else if (0 == access ("/usr/sbin/sysctl", X_OK)) | ||
740 | sbin_sysctl = "/usr/sbin/sysctl"; | ||
741 | else | ||
742 | { | ||
743 | fprintf (stderr, | ||
744 | "Fatal: executable sysctl not found in approved directories: %s\n", | ||
745 | strerror (errno)); | ||
746 | return 1; | ||
747 | } | ||
748 | } | ||
749 | |||
750 | strncpy (dev, argv[1], IFNAMSIZ); | ||
751 | dev[IFNAMSIZ - 1] = '\0'; | ||
752 | |||
753 | if (-1 == (fd_tun = init_tun (dev))) | ||
754 | { | ||
755 | fprintf (stderr, | ||
756 | "Fatal: could not initialize tun-interface `%s' with IPv6 %s/%s and IPv4 %s/%s\n", | ||
757 | dev, | ||
758 | argv[3], | ||
759 | argv[4], | ||
760 | argv[5], | ||
761 | argv[6]); | ||
762 | return 1; | ||
763 | } | ||
764 | |||
765 | if (0 != strcmp (argv[3], "-")) | ||
766 | { | ||
767 | { | ||
768 | const char *address = argv[3]; | ||
769 | long prefix_len = atol (argv[4]); | ||
770 | |||
771 | if ((prefix_len < 1) || (prefix_len > 127)) | ||
772 | { | ||
773 | fprintf (stderr, "Fatal: prefix_len out of range\n"); | ||
774 | return 1; | ||
775 | } | ||
776 | set_address6 (dev, address, prefix_len); | ||
777 | } | ||
778 | if (0 != strcmp (argv[2], "-")) | ||
779 | { | ||
780 | char *const sysctl_args[] = { | ||
781 | "sysctl", "-w", "net.ipv6.conf.all.forwarding=1", NULL | ||
782 | }; | ||
783 | if (0 != fork_and_exec (sbin_sysctl, | ||
784 | sysctl_args)) | ||
785 | { | ||
786 | fprintf (stderr, | ||
787 | "Failed to enable IPv6 forwarding. Will continue anyway.\n"); | ||
788 | } | ||
789 | } | ||
790 | } | ||
791 | |||
792 | if (0 != strcmp (argv[5], "-")) | ||
793 | { | ||
794 | { | ||
795 | const char *address = argv[5]; | ||
796 | const char *mask = argv[6]; | ||
797 | |||
798 | set_address4 (dev, address, mask); | ||
799 | } | ||
800 | if (0 != strcmp (argv[2], "-")) | ||
801 | { | ||
802 | { | ||
803 | char *const sysctl_args[] = { | ||
804 | "sysctl", "-w", "net.ipv4.ip_forward=1", NULL | ||
805 | }; | ||
806 | if (0 != fork_and_exec (sbin_sysctl, | ||
807 | sysctl_args)) | ||
808 | { | ||
809 | fprintf (stderr, | ||
810 | "Failed to enable IPv4 forwarding. Will continue anyway.\n"); | ||
811 | } | ||
812 | } | ||
813 | { | ||
814 | char *const iptables_args[] = { | ||
815 | "iptables", "-t", "nat", "-A", "POSTROUTING", "-o", argv[2], "-j", | ||
816 | "MASQUERADE", NULL | ||
817 | }; | ||
818 | if (0 != fork_and_exec (sbin_iptables, | ||
819 | iptables_args)) | ||
820 | { | ||
821 | fprintf (stderr, | ||
822 | "Failed to enable IPv4 masquerading (NAT). Will continue anyway.\n"); | ||
823 | } | ||
824 | } | ||
825 | } | ||
826 | } | ||
827 | |||
828 | uid_t uid = getuid (); | ||
829 | #ifdef HAVE_SETRESUID | ||
830 | if (0 != setresuid (uid, uid, uid)) | ||
831 | { | ||
832 | fprintf (stderr, "Failed to setresuid: %s\n", strerror (errno)); | ||
833 | global_ret = 2; | ||
834 | goto cleanup; | ||
835 | } | ||
836 | #else | ||
837 | if (0 != (setuid (uid) | seteuid (uid))) | ||
838 | { | ||
839 | fprintf (stderr, "Failed to setuid: %s\n", strerror (errno)); | ||
840 | global_ret = 2; | ||
841 | goto cleanup; | ||
842 | } | ||
843 | #endif | ||
844 | |||
845 | if (SIG_ERR == signal (SIGPIPE, SIG_IGN)) | ||
846 | { | ||
847 | fprintf (stderr, "Failed to protect against SIGPIPE: %s\n", | ||
848 | strerror (errno)); | ||
849 | /* no exit, we might as well die with SIGPIPE should it ever happen */ | ||
850 | } | ||
851 | run (fd_tun); | ||
852 | global_ret = 0; | ||
853 | cleanup: | ||
854 | (void) close (fd_tun); | ||
855 | return global_ret; | ||
856 | } | ||
857 | |||
858 | |||
859 | /* end of gnunet-helper-exit.c */ | ||