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-rw-r--r--src/nat/gnunet-service-nat_helper.c401
1 files changed, 0 insertions, 401 deletions
diff --git a/src/nat/gnunet-service-nat_helper.c b/src/nat/gnunet-service-nat_helper.c
deleted file mode 100644
index bd1645d25..000000000
--- a/src/nat/gnunet-service-nat_helper.c
+++ /dev/null
@@ -1,401 +0,0 @@
1/*
2 This file is part of GNUnet.
3 Copyright (C) 2009, 2010, 2011, 2016 GNUnet e.V.
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 nat/gnunet-service-nat_helper.c
23 * @brief runs the gnunet-helper-nat-server
24 * @author Milan Bouchet-Valat
25 * @author Christian Grothoff
26 */
27#include "platform.h"
28#include "gnunet_util_lib.h"
29#include "gnunet-service-nat_helper.h"
30
31
32/**
33 * Information we keep per NAT helper process.
34 */
35struct HelperContext
36{
37 /**
38 * IP address we pass to the NAT helper.
39 */
40 struct in_addr internal_address;
41
42 /**
43 * Function to call if we receive a reversal request.
44 */
45 GN_ReversalCallback cb;
46
47 /**
48 * Closure for @e cb.
49 */
50 void *cb_cls;
51
52 /**
53 * How long do we wait for restarting a crashed gnunet-helper-nat-server?
54 */
55 struct GNUNET_TIME_Relative server_retry_delay;
56
57 /**
58 * ID of select gnunet-helper-nat-server stdout read task
59 */
60 struct GNUNET_SCHEDULER_Task *server_read_task;
61
62 /**
63 * The process id of the server process (if behind NAT)
64 */
65 struct GNUNET_OS_Process *server_proc;
66
67 /**
68 * stdout pipe handle for the gnunet-helper-nat-server process
69 */
70 struct GNUNET_DISK_PipeHandle *server_stdout;
71
72 /**
73 * stdout file handle (for reading) for the gnunet-helper-nat-server process
74 */
75 const struct GNUNET_DISK_FileHandle *server_stdout_handle;
76
77 /**
78 * Handle to the GNUnet configuration
79 */
80 const struct GNUNET_CONFIGURATION_Handle *cfg;
81};
82
83
84/**
85 * Task that restarts the gnunet-helper-nat-server process after a crash
86 * after a certain delay.
87 *
88 * @param cls a `struct HelperContext`
89 */
90static void
91restart_nat_server (void *cls);
92
93
94/**
95 * Try again starting the helper later
96 *
97 * @param h context of the helper
98 */
99static void
100try_again (struct HelperContext *h)
101{
102 GNUNET_assert (NULL == h->server_read_task);
103 h->server_retry_delay = GNUNET_TIME_STD_BACKOFF (h->server_retry_delay);
104 h->server_read_task = GNUNET_SCHEDULER_add_delayed (h->server_retry_delay,
105 &restart_nat_server,
106 h);
107}
108
109
110/**
111 * We have been notified that gnunet-helper-nat-server has written
112 * something to stdout. Handle the output, then reschedule this
113 * function to be called again once more is available.
114 *
115 * @param cls the `struct HelperContext`
116 */
117static void
118nat_server_read (void *cls)
119{
120 struct HelperContext *h = cls;
121 char mybuf[40];
122 ssize_t bytes;
123 int port;
124 const char *port_start;
125 struct sockaddr_in sin_addr;
126
127 h->server_read_task = NULL;
128 memset (mybuf, 0, sizeof(mybuf));
129 bytes =
130 GNUNET_DISK_file_read (h->server_stdout_handle, mybuf, sizeof(mybuf));
131 if (bytes < 1)
132 {
133 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
134 "Finished reading from server stdout with code: %d\n",
135 (int) bytes);
136 if (0 != GNUNET_OS_process_kill (h->server_proc, GNUNET_TERM_SIG))
137 GNUNET_log_from_strerror (GNUNET_ERROR_TYPE_WARNING, "nat", "kill");
138 GNUNET_OS_process_wait (h->server_proc);
139 GNUNET_OS_process_destroy (h->server_proc);
140 h->server_proc = NULL;
141 GNUNET_DISK_pipe_close (h->server_stdout);
142 h->server_stdout = NULL;
143 h->server_stdout_handle = NULL;
144 try_again (h);
145 return;
146 }
147
148 port_start = NULL;
149 for (size_t i = 0; i < sizeof(mybuf); i++)
150 {
151 if (mybuf[i] == '\n')
152 {
153 mybuf[i] = '\0';
154 break;
155 }
156 if ((mybuf[i] == ':') && (i + 1 < sizeof(mybuf)))
157 {
158 mybuf[i] = '\0';
159 port_start = &mybuf[i + 1];
160 }
161 }
162
163 /* construct socket address of sender */
164 memset (&sin_addr, 0, sizeof(sin_addr));
165 sin_addr.sin_family = AF_INET;
166#if HAVE_SOCKADDR_IN_SIN_LEN
167 sin_addr.sin_len = sizeof(sin_addr);
168#endif
169 if ((NULL == port_start) || (1 != sscanf (port_start, "%d", &port)) ||
170 (-1 == inet_pton (AF_INET, mybuf, &sin_addr.sin_addr)))
171 {
172 /* should we restart gnunet-helper-nat-server? */
173 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
174 _ (
175 "gnunet-helper-nat-server generated malformed address `%s'\n"),
176 mybuf);
177 h->server_read_task =
178 GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
179 h->server_stdout_handle,
180 &nat_server_read,
181 h);
182 return;
183 }
184 sin_addr.sin_port = htons ((uint16_t) port);
185 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
186 "gnunet-helper-nat-server read: %s:%d\n",
187 mybuf,
188 port);
189 h->cb (h->cb_cls, &sin_addr);
190 h->server_read_task =
191 GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
192 h->server_stdout_handle,
193 &nat_server_read,
194 h);
195}
196
197
198/**
199 * Task that restarts the gnunet-helper-nat-server process after a crash
200 * after a certain delay.
201 *
202 * @param cls a `struct HelperContext`
203 */
204static void
205restart_nat_server (void *cls)
206{
207 struct HelperContext *h = cls;
208 char *binary;
209 char ia[INET_ADDRSTRLEN];
210
211 h->server_read_task = NULL;
212 GNUNET_assert (NULL !=
213 inet_ntop (AF_INET, &h->internal_address, ia, sizeof(ia)));
214 /* Start the server process */
215 binary = GNUNET_OS_get_suid_binary_path (h->cfg, "gnunet-helper-nat-server");
216 if (GNUNET_YES != GNUNET_OS_check_helper_binary (binary, GNUNET_YES, ia))
217 {
218 /* move instantly to max delay, as this is unlikely to be fixed */
219 h->server_retry_delay = GNUNET_TIME_STD_EXPONENTIAL_BACKOFF_THRESHOLD;
220 GNUNET_free (binary);
221 try_again (h);
222 return;
223 }
224 h->server_stdout =
225 GNUNET_DISK_pipe (GNUNET_DISK_PF_BLOCKING_RW);
226 if (NULL == h->server_stdout)
227 {
228 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "pipe");
229 GNUNET_free (binary);
230 try_again (h);
231 return;
232 }
233 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
234 "Starting `%s' at `%s'\n",
235 "gnunet-helper-nat-server",
236 ia);
237 h->server_proc = GNUNET_OS_start_process (GNUNET_OS_INHERIT_STD_NONE,
238 NULL,
239 h->server_stdout,
240 NULL,
241 binary,
242 "gnunet-helper-nat-server",
243 ia,
244 NULL);
245 GNUNET_free (binary);
246 if (NULL == h->server_proc)
247 {
248 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
249 _ ("Failed to start %s\n"),
250 "gnunet-helper-nat-server");
251 GNUNET_DISK_pipe_close (h->server_stdout);
252 h->server_stdout = NULL;
253 try_again (h);
254 return;
255 }
256 /* Close the write end of the read pipe */
257 GNUNET_DISK_pipe_close_end (h->server_stdout, GNUNET_DISK_PIPE_END_WRITE);
258 h->server_stdout_handle =
259 GNUNET_DISK_pipe_handle (h->server_stdout, GNUNET_DISK_PIPE_END_READ);
260 h->server_read_task =
261 GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_UNIT_FOREVER_REL,
262 h->server_stdout_handle,
263 &nat_server_read,
264 h);
265}
266
267
268/**
269 * Start the gnunet-helper-nat-server and process incoming
270 * requests.
271 *
272 * @param internal_address
273 * @param cb function to call if we receive a request
274 * @param cb_cls closure for @a cb
275 * @param cfg Handle to the GNUnet configuration
276 * @return NULL on error
277 */
278struct HelperContext *
279GN_start_gnunet_nat_server_ (const struct in_addr *internal_address,
280 GN_ReversalCallback cb,
281 void *cb_cls,
282 const struct GNUNET_CONFIGURATION_Handle *cfg)
283{
284 struct HelperContext *h;
285
286 h = GNUNET_new (struct HelperContext);
287 h->cb = cb;
288 h->cb_cls = cb_cls;
289 h->internal_address = *internal_address;
290 h->cfg = cfg;
291 restart_nat_server (h);
292 if (NULL == h->server_stdout)
293 {
294 GN_stop_gnunet_nat_server_ (h);
295 return NULL;
296 }
297 return h;
298}
299
300
301/**
302 * Start the gnunet-helper-nat-server and process incoming
303 * requests.
304 *
305 * @param h helper context to stop
306 */
307void
308GN_stop_gnunet_nat_server_ (struct HelperContext *h)
309{
310 if (NULL != h->server_read_task)
311 {
312 GNUNET_SCHEDULER_cancel (h->server_read_task);
313 h->server_read_task = NULL;
314 }
315 if (NULL != h->server_proc)
316 {
317 if (0 != GNUNET_OS_process_kill (h->server_proc, GNUNET_TERM_SIG))
318 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "kill");
319 GNUNET_OS_process_wait (h->server_proc);
320 GNUNET_OS_process_destroy (h->server_proc);
321 h->server_proc = NULL;
322 GNUNET_DISK_pipe_close (h->server_stdout);
323 h->server_stdout = NULL;
324 h->server_stdout_handle = NULL;
325 }
326 if (NULL != h->server_stdout)
327 {
328 GNUNET_DISK_pipe_close (h->server_stdout);
329 h->server_stdout = NULL;
330 h->server_stdout_handle = NULL;
331 }
332 GNUNET_free (h);
333}
334
335
336/**
337 * We want to connect to a peer that is behind NAT. Run the
338 * gnunet-helper-nat-client to send dummy ICMP responses to cause
339 * that peer to connect to us (connection reversal).
340 *
341 * @param internal_address out internal address to use
342 * @param internal_port port to use
343 * @param remote_v4 the address of the peer (IPv4-only)
344 * @param cfg handle to the GNUnet configuration
345 * @return #GNUNET_SYSERR on error,
346 * #GNUNET_OK otherwise
347 */
348int
349GN_request_connection_reversal (const struct in_addr *internal_address,
350 uint16_t internal_port,
351 const struct in_addr *remote_v4,
352 const struct GNUNET_CONFIGURATION_Handle *cfg)
353{
354 char intv4[INET_ADDRSTRLEN];
355 char remv4[INET_ADDRSTRLEN];
356 char port_as_string[6];
357 struct GNUNET_OS_Process *proc;
358 char *binary;
359
360 if (NULL == inet_ntop (AF_INET, internal_address, intv4, INET_ADDRSTRLEN))
361 {
362 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
363 return GNUNET_SYSERR;
364 }
365 if (NULL == inet_ntop (AF_INET, remote_v4, remv4, INET_ADDRSTRLEN))
366 {
367 GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "inet_ntop");
368 return GNUNET_SYSERR;
369 }
370 GNUNET_snprintf (port_as_string,
371 sizeof(port_as_string),
372 "%d",
373 internal_port);
374 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
375 "Running gnunet-helper-nat-client %s %s %u\n",
376 intv4,
377 remv4,
378 internal_port);
379 binary = GNUNET_OS_get_suid_binary_path (cfg, "gnunet-helper-nat-client");
380 proc = GNUNET_OS_start_process (GNUNET_OS_INHERIT_STD_NONE,
381 NULL,
382 NULL,
383 NULL,
384 binary,
385 "gnunet-helper-nat-client",
386 intv4,
387 remv4,
388 port_as_string,
389 NULL);
390 GNUNET_free (binary);
391 if (NULL == proc)
392 return GNUNET_SYSERR;
393 /* we know that the gnunet-helper-nat-client will terminate virtually
394 * instantly */
395 GNUNET_OS_process_wait (proc);
396 GNUNET_OS_process_destroy (proc);
397 return GNUNET_OK;
398}
399
400
401/* end of gnunet-service-nat_helper.c */
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-24 02:27:17 +0000