2 This file is part of GNUnet.
3 (C) 2011 Christian Grothoff (and other contributing authors)
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22 * @file nat/nat_mini.c
23 * @brief functions for interaction with miniupnp; tested with miniupnpc 1.5
24 * @author Christian Grothoff
27 #include "gnunet_util_lib.h"
28 #include "gnunet_nat_lib.h"
31 #define LOG(kind,...) GNUNET_log_from (kind, "nat", __VA_ARGS__)
34 * How long do we give upnpc to create a mapping?
36 #define MAP_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15)
39 * How long do we give upnpc to remove a mapping?
41 #define UNMAP_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)
44 * How often do we check for changes in the mapping?
46 #define MAP_REFRESH_FREQ GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 5)
51 * Opaque handle to cancel "GNUNET_NAT_mini_get_external_ipv4" operation.
53 struct GNUNET_NAT_ExternalHandle
57 * Function to call with the result.
59 GNUNET_NAT_IPCallback cb;
69 GNUNET_SCHEDULER_TaskIdentifier task;
72 * Handle to 'external-ip' process.
74 struct GNUNET_OS_Process *eip;
77 * Handle to stdout pipe of 'external-ip'.
79 struct GNUNET_DISK_PipeHandle *opipe;
82 * Read handle of 'opipe'.
84 const struct GNUNET_DISK_FileHandle *r;
87 * When should this operation time out?
89 struct GNUNET_TIME_Absolute timeout;
92 * Number of bytes in 'buf' that are valid.
97 * Destination of our read operation (output of 'external-ip').
105 * Read the output of 'external-ip' into buf. When complete, parse the
106 * address and call our callback.
108 * @param cls the 'struct GNUNET_NAT_ExternalHandle'
109 * @param tc scheduler context
112 read_external_ipv4 (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
114 struct GNUNET_NAT_ExternalHandle *eh = cls;
119 eh->task = GNUNET_SCHEDULER_NO_TASK;
120 if (GNUNET_YES == GNUNET_NETWORK_fdset_handle_isset (tc->read_ready, eh->r))
122 GNUNET_DISK_file_read (eh->r, &eh->buf[eh->off],
123 sizeof (eh->buf) - eh->off);
125 ret = -1; /* error reading, timeout, etc. */
128 /* try to read more */
131 GNUNET_SCHEDULER_add_read_file (GNUNET_TIME_absolute_get_remaining
132 (eh->timeout), eh->r,
133 &read_external_ipv4, eh);
137 if ((eh->off > 7) && (eh->buf[eh->off - 1] == '\n'))
139 eh->buf[eh->off - 1] = '\0';
140 if (1 == inet_pton (AF_INET, eh->buf, &addr))
142 if (addr.s_addr == 0)
143 iret = GNUNET_NO; /* got 0.0.0.0 */
148 eh->cb (eh->cb_cls, (iret == GNUNET_OK) ? &addr : NULL);
149 GNUNET_NAT_mini_get_external_ipv4_cancel (eh);
154 * Try to get the external IPv4 address of this peer.
156 * @param timeout when to fail
157 * @param cb function to call with result
158 * @param cb_cls closure for 'cb'
159 * @return handle for cancellation (can only be used until 'cb' is called), NULL on error
161 struct GNUNET_NAT_ExternalHandle *
162 GNUNET_NAT_mini_get_external_ipv4 (struct GNUNET_TIME_Relative timeout,
163 GNUNET_NAT_IPCallback cb, void *cb_cls)
165 struct GNUNET_NAT_ExternalHandle *eh;
167 if (GNUNET_SYSERR == GNUNET_OS_check_helper_binary ("external-ip", GNUNET_NO, NULL))
169 LOG (GNUNET_ERROR_TYPE_INFO,
170 _("`external-ip' command not found\n"));
173 LOG (GNUNET_ERROR_TYPE_DEBUG,
174 "Running `external-ip' to determine our external IP\n");
175 eh = GNUNET_malloc (sizeof (struct GNUNET_NAT_ExternalHandle));
178 eh->opipe = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_YES, GNUNET_NO, GNUNET_YES);
179 if (NULL == eh->opipe)
185 GNUNET_OS_start_process (GNUNET_NO, 0, NULL, eh->opipe, "external-ip", "external-ip",
189 GNUNET_DISK_pipe_close (eh->opipe);
193 GNUNET_DISK_pipe_close_end (eh->opipe, GNUNET_DISK_PIPE_END_WRITE);
194 eh->timeout = GNUNET_TIME_relative_to_absolute (timeout);
195 eh->r = GNUNET_DISK_pipe_handle (eh->opipe, GNUNET_DISK_PIPE_END_READ);
197 GNUNET_SCHEDULER_add_read_file (timeout, eh->r, &read_external_ipv4, eh);
205 * @param eh operation to cancel
208 GNUNET_NAT_mini_get_external_ipv4_cancel (struct GNUNET_NAT_ExternalHandle *eh)
210 (void) GNUNET_OS_process_kill (eh->eip, SIGKILL);
211 GNUNET_OS_process_destroy (eh->eip);
212 GNUNET_DISK_pipe_close (eh->opipe);
213 if (GNUNET_SCHEDULER_NO_TASK != eh->task)
214 GNUNET_SCHEDULER_cancel (eh->task);
220 * Handle to a mapping created with upnpc.
222 struct GNUNET_NAT_MiniHandle
226 * Function to call on mapping changes.
228 GNUNET_NAT_AddressCallback ac;
236 * Command used to install the map.
238 struct GNUNET_OS_CommandHandle *map_cmd;
241 * Command used to refresh our map information.
243 struct GNUNET_OS_CommandHandle *refresh_cmd;
246 * Command used to remove the mapping.
248 struct GNUNET_OS_CommandHandle *unmap_cmd;
251 * Our current external mapping (if we have one).
253 struct sockaddr_in current_addr;
256 * We check the mapping periodically to see if it
257 * still works. This task triggers the check.
259 GNUNET_SCHEDULER_TaskIdentifier refresh_task;
262 * Are we mapping TCP or UDP?
267 * Did we succeed with creating a mapping?
272 * Did we find our mapping during refresh scan?
277 * Which port are we mapping?
285 * Run upnpc -l to find out if our mapping changed.
287 * @param cls the 'struct GNUNET_NAT_MiniHandle'
288 * @param tc scheduler context
291 do_refresh (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
295 * Process the output from the 'upnpc -r' command.
297 * @param cls the 'struct GNUNET_NAT_MiniHandle'
298 * @param line line of output, NULL at the end
301 process_map_output (void *cls, const char *line);
305 * Process the output from 'upnpc -l' to see if our
306 * external mapping changed. If so, do the notifications.
308 * @param cls the 'struct GNUNET_NAT_MiniHandle'
309 * @param line line of output, NULL at the end
312 process_refresh_output (void *cls, const char *line)
314 struct GNUNET_NAT_MiniHandle *mini = cls;
322 GNUNET_OS_command_stop (mini->refresh_cmd);
323 mini->refresh_cmd = NULL;
324 if (mini->found == GNUNET_NO)
326 /* mapping disappeared, try to re-create */
329 mini->ac (mini->ac_cls, GNUNET_NO,
330 (const struct sockaddr *) &mini->current_addr,
331 sizeof (mini->current_addr));
332 mini->did_map = GNUNET_NO;
334 GNUNET_snprintf (pstr, sizeof (pstr), "%u", (unsigned int) mini->port);
336 GNUNET_OS_command_run (&process_map_output, mini, MAP_TIMEOUT,
337 "upnpc", "upnpc", "-r", pstr,
338 mini->is_tcp ? "tcp" : "udp", NULL);
339 if (NULL != mini->map_cmd)
343 GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ, &do_refresh, mini);
347 return; /* never mapped, won't find our mapping anyway */
349 /* we're looking for output of the form:
350 * "ExternalIPAddress = 12.134.41.124" */
352 s = strstr (line, "ExternalIPAddress = ");
355 s += strlen ("ExternalIPAddress = ");
356 if (1 != inet_pton (AF_INET, s, &exip))
358 if (exip.s_addr == mini->current_addr.sin_addr.s_addr)
359 return; /* no change */
361 mini->ac (mini->ac_cls, GNUNET_NO,
362 (const struct sockaddr *) &mini->current_addr,
363 sizeof (mini->current_addr));
364 mini->current_addr.sin_addr = exip;
365 mini->ac (mini->ac_cls, GNUNET_YES,
366 (const struct sockaddr *) &mini->current_addr,
367 sizeof (mini->current_addr));
371 * we're looking for output of the form:
373 * "0 TCP 3000->192.168.2.150:3000 'libminiupnpc' ''"
374 * "1 UDP 3001->192.168.2.150:3001 'libminiupnpc' ''"
376 * the pattern we look for is:
378 * "%s TCP PORT->STRING:OURPORT *" or
379 * "%s UDP PORT->STRING:OURPORT *"
381 GNUNET_snprintf (pstr, sizeof (pstr), ":%u ", mini->port);
382 if (NULL == (s = strstr (line, "->")))
384 if (NULL == strstr (s, pstr))
388 (mini->is_tcp) ? "%*u TCP %u->%*s:%*u %*s" :
389 "%*u UDP %u->%*s:%*u %*s", &nport))
391 mini->found = GNUNET_YES;
392 if (nport == ntohs (mini->current_addr.sin_port))
393 return; /* no change */
395 /* external port changed, update mapping */
396 mini->ac (mini->ac_cls, GNUNET_NO,
397 (const struct sockaddr *) &mini->current_addr,
398 sizeof (mini->current_addr));
399 mini->current_addr.sin_port = htons ((uint16_t) nport);
400 mini->ac (mini->ac_cls, GNUNET_YES,
401 (const struct sockaddr *) &mini->current_addr,
402 sizeof (mini->current_addr));
407 * Run upnpc -l to find out if our mapping changed.
409 * @param cls the 'struct GNUNET_NAT_MiniHandle'
410 * @param tc scheduler context
413 do_refresh (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
415 struct GNUNET_NAT_MiniHandle *mini = cls;
417 LOG (GNUNET_ERROR_TYPE_DEBUG,
418 "Running `upnpc' to check if our mapping still exists\n");
419 mini->refresh_task = GNUNET_SCHEDULER_NO_TASK;
420 mini->found = GNUNET_NO;
422 GNUNET_OS_command_run (&process_refresh_output, mini, MAP_TIMEOUT,
423 "upnpc", "upnpc", "-l", NULL);
428 * Process the output from the 'upnpc -r' command.
430 * @param cls the 'struct GNUNET_NAT_MiniHandle'
431 * @param line line of output, NULL at the end
434 process_map_output (void *cls, const char *line)
436 struct GNUNET_NAT_MiniHandle *mini = cls;
444 GNUNET_OS_command_stop (mini->map_cmd);
445 mini->map_cmd = NULL;
447 GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ, &do_refresh, mini);
451 * The upnpc output we're after looks like this:
453 * "external 87.123.42.204:3000 TCP is redirected to internal 192.168.2.150:3000"
455 if ((NULL == (ipaddr = strstr (line, " "))) ||
456 (NULL == (pstr = strstr (ipaddr, ":"))) ||
457 (1 != SSCANF (pstr + 1, "%u", &port)))
459 return; /* skip line */
461 ipa = GNUNET_strdup (ipaddr + 1);
462 strstr (ipa, ":")[0] = '\0';
463 if (1 != inet_pton (AF_INET, ipa, &mini->current_addr.sin_addr))
466 return; /* skip line */
470 mini->current_addr.sin_port = htons (port);
471 mini->current_addr.sin_family = AF_INET;
472 #if HAVE_SOCKADDR_IN_SIN_LEN
473 mini->current_addr.sin_len = sizeof (struct sockaddr_in);
475 mini->did_map = GNUNET_YES;
476 mini->ac (mini->ac_cls, GNUNET_YES,
477 (const struct sockaddr *) &mini->current_addr,
478 sizeof (mini->current_addr));
483 * Start mapping the given port using (mini)upnpc. This function
484 * should typically not be used directly (it is used within the
485 * general-purpose 'GNUNET_NAT_register' code). However, it can be
486 * used if specifically UPnP-based NAT traversal is to be used or
489 * @param port port to map
490 * @param is_tcp GNUNET_YES to map TCP, GNUNET_NO for UDP
491 * @param ac function to call with mapping result
492 * @param ac_cls closure for 'ac'
493 * @return NULL on error (no 'upnpc' installed)
495 struct GNUNET_NAT_MiniHandle *
496 GNUNET_NAT_mini_map_start (uint16_t port, int is_tcp,
497 GNUNET_NAT_AddressCallback ac, void *ac_cls)
499 struct GNUNET_NAT_MiniHandle *ret;
502 if (GNUNET_SYSERR == GNUNET_OS_check_helper_binary ("upnpc", GNUNET_NO, NULL))
504 LOG (GNUNET_ERROR_TYPE_INFO,
505 _("`upnpc' command not found\n"));
508 LOG (GNUNET_ERROR_TYPE_DEBUG,
509 "Running `upnpc' to install mapping\n");
510 ret = GNUNET_malloc (sizeof (struct GNUNET_NAT_MiniHandle));
512 ret->ac_cls = ac_cls;
513 ret->is_tcp = is_tcp;
515 GNUNET_snprintf (pstr, sizeof (pstr), "%u", (unsigned int) port);
517 GNUNET_OS_command_run (&process_map_output, ret, MAP_TIMEOUT, "upnpc",
518 "upnpc", "-r", pstr, is_tcp ? "tcp" : "udp", NULL);
519 if (NULL != ret->map_cmd)
522 GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ, &do_refresh, ret);
529 * Process output from our 'unmap' command.
531 * @param cls the 'struct GNUNET_NAT_MiniHandle'
532 * @param line line of output, NULL at the end
535 process_unmap_output (void *cls, const char *line)
537 struct GNUNET_NAT_MiniHandle *mini = cls;
541 LOG (GNUNET_ERROR_TYPE_DEBUG, "UPnP unmap done\n");
542 GNUNET_OS_command_stop (mini->unmap_cmd);
543 mini->unmap_cmd = NULL;
547 /* we don't really care about the output... */
552 * Remove a mapping created with (mini)upnpc. Calling
553 * this function will give 'upnpc' 1s to remove tha mapping,
554 * so while this function is non-blocking, a task will be
555 * left with the scheduler for up to 1s past this call.
557 * @param mini the handle
560 GNUNET_NAT_mini_map_stop (struct GNUNET_NAT_MiniHandle *mini)
564 if (GNUNET_SCHEDULER_NO_TASK != mini->refresh_task)
566 GNUNET_SCHEDULER_cancel (mini->refresh_task);
567 mini->refresh_task = GNUNET_SCHEDULER_NO_TASK;
569 if (mini->refresh_cmd != NULL)
571 GNUNET_OS_command_stop (mini->refresh_cmd);
572 mini->refresh_cmd = NULL;
576 if (mini->map_cmd != NULL)
578 GNUNET_OS_command_stop (mini->map_cmd);
579 mini->map_cmd = NULL;
584 mini->ac (mini->ac_cls, GNUNET_NO,
585 (const struct sockaddr *) &mini->current_addr,
586 sizeof (mini->current_addr));
587 /* Note: oddly enough, deletion uses the external port whereas
588 * addition uses the internal port; this rarely matters since they
589 * often are the same, but it might... */
590 GNUNET_snprintf (pstr, sizeof (pstr), "%u",
591 (unsigned int) ntohs (mini->current_addr.sin_port));
592 LOG (GNUNET_ERROR_TYPE_DEBUG, "Unmapping port %u with UPnP\n",
593 ntohs (mini->current_addr.sin_port));
595 GNUNET_OS_command_run (&process_unmap_output, mini, UNMAP_TIMEOUT,
596 "upnpc", "upnpc", "-d", pstr,
597 mini->is_tcp ? "tcp" : "udp", NULL);
601 /* end of nat_mini.c */