2 This file is part of GNUnet.
3 (C) 2011 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
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 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
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 DEBUG_NAT GNUNET_NO
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 eh = GNUNET_malloc (sizeof (struct GNUNET_NAT_ExternalHandle));
170 eh->opipe = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_NO, GNUNET_YES);
171 if (NULL == eh->opipe)
177 GNUNET_OS_start_process (NULL, eh->opipe, "external-ip", "external-ip",
181 GNUNET_DISK_pipe_close (eh->opipe);
185 GNUNET_DISK_pipe_close_end (eh->opipe, GNUNET_DISK_PIPE_END_WRITE);
186 eh->timeout = GNUNET_TIME_relative_to_absolute (timeout);
187 eh->r = GNUNET_DISK_pipe_handle (eh->opipe, GNUNET_DISK_PIPE_END_READ);
189 GNUNET_SCHEDULER_add_read_file (timeout, eh->r, &read_external_ipv4, eh);
197 * @param eh operation to cancel
200 GNUNET_NAT_mini_get_external_ipv4_cancel (struct GNUNET_NAT_ExternalHandle *eh)
202 (void) GNUNET_OS_process_kill (eh->eip, SIGKILL);
203 GNUNET_OS_process_close (eh->eip);
204 GNUNET_DISK_pipe_close (eh->opipe);
205 if (GNUNET_SCHEDULER_NO_TASK != eh->task)
206 GNUNET_SCHEDULER_cancel (eh->task);
212 * Handle to a mapping created with upnpc.
214 struct GNUNET_NAT_MiniHandle
218 * Function to call on mapping changes.
220 GNUNET_NAT_AddressCallback ac;
228 * Command used to install the map.
230 struct GNUNET_OS_CommandHandle *map_cmd;
233 * Command used to refresh our map information.
235 struct GNUNET_OS_CommandHandle *refresh_cmd;
238 * Command used to remove the mapping.
240 struct GNUNET_OS_CommandHandle *unmap_cmd;
243 * Our current external mapping (if we have one).
245 struct sockaddr_in current_addr;
248 * We check the mapping periodically to see if it
249 * still works. This task triggers the check.
251 GNUNET_SCHEDULER_TaskIdentifier refresh_task;
254 * Are we mapping TCP or UDP?
259 * Did we succeed with creating a mapping?
264 * Did we find our mapping during refresh scan?
269 * Which port are we mapping?
277 * Run upnpc -l to find out if our mapping changed.
279 * @param cls the 'struct GNUNET_NAT_MiniHandle'
280 * @param tc scheduler context
283 do_refresh (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
287 * Process the output from the 'upnpc -r' command.
289 * @param cls the 'struct GNUNET_NAT_MiniHandle'
290 * @param line line of output, NULL at the end
293 process_map_output (void *cls, const char *line);
297 * Process the output from 'upnpc -l' to see if our
298 * external mapping changed. If so, do the notifications.
300 * @param cls the 'struct GNUNET_NAT_MiniHandle'
301 * @param line line of output, NULL at the end
304 process_refresh_output (void *cls, const char *line)
306 struct GNUNET_NAT_MiniHandle *mini = cls;
314 GNUNET_OS_command_stop (mini->refresh_cmd);
315 mini->refresh_cmd = NULL;
316 if (mini->found == GNUNET_NO)
318 /* mapping disappeared, try to re-create */
321 mini->ac (mini->ac_cls, GNUNET_NO,
322 (const struct sockaddr *) &mini->current_addr,
323 sizeof (mini->current_addr));
324 mini->did_map = GNUNET_NO;
326 GNUNET_snprintf (pstr, sizeof (pstr), "%u", (unsigned int) mini->port);
328 GNUNET_OS_command_run (&process_map_output, mini, MAP_TIMEOUT,
329 "upnpc", "upnpc", "-r", pstr,
330 mini->is_tcp ? "tcp" : "udp", NULL);
331 if (NULL != mini->map_cmd)
335 GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ, &do_refresh, mini);
339 return; /* never mapped, won't find our mapping anyway */
341 /* we're looking for output of the form:
342 * "ExternalIPAddress = 12.134.41.124" */
344 s = strstr (line, "ExternalIPAddress = ");
347 s += strlen ("ExternalIPAddress = ");
348 if (1 != inet_pton (AF_INET, s, &exip))
350 if (exip.s_addr == mini->current_addr.sin_addr.s_addr)
351 return; /* no change */
353 mini->ac (mini->ac_cls, GNUNET_NO,
354 (const struct sockaddr *) &mini->current_addr,
355 sizeof (mini->current_addr));
356 mini->current_addr.sin_addr = exip;
357 mini->ac (mini->ac_cls, GNUNET_YES,
358 (const struct sockaddr *) &mini->current_addr,
359 sizeof (mini->current_addr));
363 * we're looking for output of the form:
365 * "0 TCP 3000->192.168.2.150:3000 'libminiupnpc' ''"
366 * "1 UDP 3001->192.168.2.150:3001 'libminiupnpc' ''"
368 * the pattern we look for is:
370 * "%s TCP PORT->STRING:OURPORT *" or
371 * "%s UDP PORT->STRING:OURPORT *"
373 GNUNET_snprintf (pstr, sizeof (pstr), ":%u ", mini->port);
374 if (NULL == (s = strstr (line, "->")))
376 if (NULL == strstr (s, pstr))
380 (mini->is_tcp) ? "%*u TCP %u->%*s:%*u %*s" :
381 "%*u UDP %u->%*s:%*u %*s", &nport))
383 mini->found = GNUNET_YES;
384 if (nport == ntohs (mini->current_addr.sin_port))
385 return; /* no change */
387 /* external port changed, update mapping */
388 mini->ac (mini->ac_cls, GNUNET_NO,
389 (const struct sockaddr *) &mini->current_addr,
390 sizeof (mini->current_addr));
391 mini->current_addr.sin_port = htons ((uint16_t) nport);
392 mini->ac (mini->ac_cls, GNUNET_YES,
393 (const struct sockaddr *) &mini->current_addr,
394 sizeof (mini->current_addr));
399 * Run upnpc -l to find out if our mapping changed.
401 * @param cls the 'struct GNUNET_NAT_MiniHandle'
402 * @param tc scheduler context
405 do_refresh (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
407 struct GNUNET_NAT_MiniHandle *mini = cls;
409 mini->refresh_task = GNUNET_SCHEDULER_NO_TASK;
410 mini->found = GNUNET_NO;
412 GNUNET_OS_command_run (&process_refresh_output, mini, MAP_TIMEOUT,
413 "upnpc", "upnpc", "-l", NULL);
418 * Process the output from the 'upnpc -r' command.
420 * @param cls the 'struct GNUNET_NAT_MiniHandle'
421 * @param line line of output, NULL at the end
424 process_map_output (void *cls, const char *line)
426 struct GNUNET_NAT_MiniHandle *mini = cls;
434 GNUNET_OS_command_stop (mini->map_cmd);
435 mini->map_cmd = NULL;
437 GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ, &do_refresh, mini);
441 * The upnpc output we're after looks like this:
443 * "external 87.123.42.204:3000 TCP is redirected to internal 192.168.2.150:3000"
445 if ((NULL == (ipaddr = strstr (line, " "))) ||
446 (NULL == (pstr = strstr (ipaddr, ":"))) ||
447 (1 != sscanf (pstr + 1, "%u", &port)))
449 return; /* skip line */
451 ipa = GNUNET_strdup (ipaddr + 1);
452 strstr (ipa, ":")[0] = '\0';
453 if (1 != inet_pton (AF_INET, ipa, &mini->current_addr.sin_addr))
456 return; /* skip line */
460 mini->current_addr.sin_port = htons (port);
461 mini->current_addr.sin_family = AF_INET;
462 #if HAVE_SOCKADDR_IN_SIN_LEN
463 mini->current_addr.sin_len = sizeof (struct sockaddr_in);
465 mini->did_map = GNUNET_YES;
466 mini->ac (mini->ac_cls, GNUNET_YES,
467 (const struct sockaddr *) &mini->current_addr,
468 sizeof (mini->current_addr));
473 * Start mapping the given port using (mini)upnpc. This function
474 * should typically not be used directly (it is used within the
475 * general-purpose 'GNUNET_NAT_register' code). However, it can be
476 * used if specifically UPnP-based NAT traversal is to be used or
479 * @param port port to map
480 * @param is_tcp GNUNET_YES to map TCP, GNUNET_NO for UDP
481 * @param ac function to call with mapping result
482 * @param ac_cls closure for 'ac'
483 * @return NULL on error (no 'upnpc' installed)
485 struct GNUNET_NAT_MiniHandle *
486 GNUNET_NAT_mini_map_start (uint16_t port, int is_tcp,
487 GNUNET_NAT_AddressCallback ac, void *ac_cls)
489 struct GNUNET_NAT_MiniHandle *ret;
492 if (GNUNET_SYSERR == GNUNET_OS_check_helper_binary ("upnpc"))
494 ret = GNUNET_malloc (sizeof (struct GNUNET_NAT_MiniHandle));
496 ret->ac_cls = ac_cls;
497 ret->is_tcp = is_tcp;
499 GNUNET_snprintf (pstr, sizeof (pstr), "%u", (unsigned int) port);
501 GNUNET_OS_command_run (&process_map_output, ret, MAP_TIMEOUT, "upnpc",
502 "upnpc", "-r", pstr, is_tcp ? "tcp" : "udp", NULL);
503 if (NULL != ret->map_cmd)
506 GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ, &do_refresh, ret);
513 * Process output from our 'unmap' command.
515 * @param cls the 'struct GNUNET_NAT_MiniHandle'
516 * @param line line of output, NULL at the end
519 process_unmap_output (void *cls, const char *line)
521 struct GNUNET_NAT_MiniHandle *mini = cls;
526 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "nat", "UPnP unmap done\n");
528 GNUNET_OS_command_stop (mini->unmap_cmd);
529 mini->unmap_cmd = NULL;
533 /* we don't really care about the output... */
538 * Remove a mapping created with (mini)upnpc. Calling
539 * this function will give 'upnpc' 1s to remove tha mapping,
540 * so while this function is non-blocking, a task will be
541 * left with the scheduler for up to 1s past this call.
543 * @param mini the handle
546 GNUNET_NAT_mini_map_stop (struct GNUNET_NAT_MiniHandle *mini)
550 if (GNUNET_SCHEDULER_NO_TASK != mini->refresh_task)
552 GNUNET_SCHEDULER_cancel (mini->refresh_task);
553 mini->refresh_task = GNUNET_SCHEDULER_NO_TASK;
555 if (mini->refresh_cmd != NULL)
557 GNUNET_OS_command_stop (mini->refresh_cmd);
558 mini->refresh_cmd = NULL;
562 if (mini->map_cmd != NULL)
564 GNUNET_OS_command_stop (mini->map_cmd);
565 mini->map_cmd = NULL;
570 mini->ac (mini->ac_cls, GNUNET_NO,
571 (const struct sockaddr *) &mini->current_addr,
572 sizeof (mini->current_addr));
573 /* Note: oddly enough, deletion uses the external port whereas
574 * addition uses the internal port; this rarely matters since they
575 * often are the same, but it might... */
576 GNUNET_snprintf (pstr, sizeof (pstr), "%u",
577 (unsigned int) ntohs (mini->current_addr.sin_port));
579 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG, "nat",
580 "Unmapping port %u with UPnP\n",
581 ntohs (mini->current_addr.sin_port));
584 GNUNET_OS_command_run (&process_unmap_output, mini, UNMAP_TIMEOUT,
585 "upnpc", "upnpc", "-d", pstr,
586 mini->is_tcp ? "tcp" : "udp", NULL);
590 /* end of nat_mini.c */