2 This file is part of GNUnet.
3 (C) 2011 Christian Grothoff (and other contributing authors)
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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
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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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22 * @file nat/nat_mini.c
23 * @brief functions for interaction with miniupnp
24 * @author Christian Grothoff
27 #include "gnunet_util_lib.h"
28 #include "gnunet_nat_lib.h"
32 * How long do we give upnpc to create a mapping?
34 #define MAP_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15)
38 * How long do we give upnpc to remove a mapping?
40 #define UNMAP_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)
43 * How often do we check for changes in the mapping?
45 #define MAP_REFRESH_FREQ GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 15)
49 * Try to get the external IPv4 address of this peer.
50 * Note: calling this function may block this process
51 * for a few seconds (!).
53 * @param addr address to set
54 * @return GNUNET_OK on success,
55 * GNUNET_NO if the result is questionable,
56 * GNUNET_SYSERR on error
59 GNUNET_NAT_mini_get_external_ipv4 (struct in_addr *addr)
61 struct GNUNET_OS_Process *eip;
62 struct GNUNET_DISK_PipeHandle *opipe;
63 const struct GNUNET_DISK_FileHandle *r;
69 opipe = GNUNET_DISK_pipe (GNUNET_YES,
74 eip = GNUNET_OS_start_process (NULL,
80 GNUNET_DISK_pipe_close (opipe);
83 GNUNET_DISK_pipe_close_end (opipe, GNUNET_DISK_PIPE_END_WRITE);
85 r = GNUNET_DISK_pipe_handle (opipe,
86 GNUNET_DISK_PIPE_END_READ);
88 while (0 < (ret = GNUNET_DISK_file_read (r, &buf[off], sizeof (buf)-off)))
91 (buf[off-1] == '\n') )
94 if (1 == inet_pton (AF_INET, buf, addr))
96 if (addr->s_addr == 0)
97 iret = GNUNET_NO; /* got 0.0.0.0 */
101 (void) GNUNET_OS_process_kill (eip, SIGKILL);
102 GNUNET_OS_process_close (eip);
103 GNUNET_DISK_pipe_close (opipe);
109 * Handle to a mapping created with upnpc.
111 struct GNUNET_NAT_MiniHandle
115 * Function to call on mapping changes.
117 GNUNET_NAT_AddressCallback ac;
125 * Command used to install the map.
127 struct GNUNET_OS_CommandHandle *map_cmd;
130 * Command used to refresh our map information.
132 struct GNUNET_OS_CommandHandle *refresh_cmd;
135 * Command used to remove the mapping.
137 struct GNUNET_OS_CommandHandle *unmap_cmd;
140 * Our current external mapping (if we have one).
142 struct sockaddr_in current_addr;
145 * We check the mapping periodically to see if it
146 * still works. This task triggers the check.
148 GNUNET_SCHEDULER_TaskIdentifier refresh_task;
151 * Are we mapping TCP or UDP?
156 * Did we succeed with creating a mapping?
161 * Which port are we mapping?
169 * Run upnpc -l to find out if our mapping changed.
171 * @param cls the 'struct GNUNET_NAT_MiniHandle'
172 * @param tc scheduler context
175 do_refresh (void *cls,
176 const struct GNUNET_SCHEDULER_TaskContext *tc);
180 * Process the output from 'upnpc -l' to see if our
181 * external mapping changed. If so, do the notifications.
183 * @param cls the 'struct GNUNET_NAT_MiniHandle'
184 * @param line line of output, NULL at the end
187 process_refresh_output (void *cls,
190 struct GNUNET_NAT_MiniHandle *mini = cls;
194 GNUNET_OS_command_stop (mini->refresh_cmd);
195 mini->refresh_cmd = NULL;
196 mini->refresh_task = GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ,
201 /* FIXME: parse 'line' */
203 "Refresh output: `%s'\n",
209 * Run upnpc -l to find out if our mapping changed.
211 * @param cls the 'struct GNUNET_NAT_MiniHandle'
212 * @param tc scheduler context
215 do_refresh (void *cls,
216 const struct GNUNET_SCHEDULER_TaskContext *tc)
218 struct GNUNET_NAT_MiniHandle *mini = cls;
220 mini->refresh_task = GNUNET_SCHEDULER_NO_TASK;
221 mini->refresh_cmd = GNUNET_OS_command_run (&process_refresh_output,
232 * Process the output from the 'upnpc -r' command.
234 * @param cls the 'struct GNUNET_NAT_MiniHandle'
235 * @param line line of output, NULL at the end
238 process_map_output (void *cls,
241 struct GNUNET_NAT_MiniHandle *mini = cls;
249 GNUNET_OS_command_stop (mini->map_cmd);
250 mini->map_cmd = NULL;
251 if (mini->did_map == GNUNET_YES)
252 mini->refresh_task = GNUNET_SCHEDULER_add_delayed (MAP_REFRESH_FREQ,
258 The upnpc output we're after looks like this:
260 "external 87.123.42.204:3000 TCP is redirected to internal 192.168.2.150:3000"
262 if ( (NULL == (ipaddr = strstr (line, " "))) ||
263 (NULL == (pstr = strstr (ipaddr, ":"))) ||
264 (1 != sscanf (pstr + 1, "%u", &port)) )
267 "Skipping output `%s'\n",
269 return; /* skip line */
271 ipa = GNUNET_strdup (ipaddr + 1);
272 strstr (ipa, ":")[0] = '\0';
273 if (1 != inet_pton (AF_INET,
275 &mini->current_addr.sin_addr))
279 "Skipping output `%s'\n",
281 return; /* skip line */
285 mini->current_addr.sin_port = htons (port);
286 mini->current_addr.sin_family = AF_INET;
287 #if HAVE_SOCKADDR_IN_SIN_LEN
288 mini->current_addr.sin_len = sizeof (struct sockaddr_in);
290 mini->did_map = GNUNET_YES;
291 mini->ac (mini->ac_cls, GNUNET_YES,
292 (const struct sockaddr*) &mini->current_addr,
293 sizeof (mini->current_addr));
298 * Start mapping the given port using (mini)upnpc. This function
299 * should typically not be used directly (it is used within the
300 * general-purpose 'GNUNET_NAT_register' code). However, it can be
301 * used if specifically UPnP-based NAT traversal is to be used or
304 * @param port port to map
305 * @param is_tcp GNUNET_YES to map TCP, GNUNET_NO for UDP
306 * @param ac function to call with mapping result
307 * @param ac_cls closure for 'ac'
308 * @return NULL on error
310 struct GNUNET_NAT_MiniHandle *
311 GNUNET_NAT_mini_map_start (uint16_t port,
313 GNUNET_NAT_AddressCallback ac,
316 struct GNUNET_NAT_MiniHandle *ret;
319 ret = GNUNET_malloc (sizeof (struct GNUNET_NAT_MiniHandle));
321 ret->ac_cls = ac_cls;
322 ret->is_tcp = is_tcp;
324 GNUNET_snprintf (pstr, sizeof (pstr),
326 (unsigned int) port);
327 ret->map_cmd = GNUNET_OS_command_run (&process_map_output,
333 is_tcp ? "tcp" : "udp",
341 * Process output from our 'unmap' command.
343 * @param cls the 'struct GNUNET_NAT_MiniHandle'
344 * @param line line of output, NULL at the end
347 process_unmap_output (void *cls,
350 struct GNUNET_NAT_MiniHandle *mini = cls;
354 GNUNET_OS_command_stop (mini->unmap_cmd);
355 mini->unmap_cmd = NULL;
359 /* we don't really care about the output... */
364 * Remove a mapping created with (mini)upnpc. Calling
365 * this function will give 'upnpc' 1s to remove tha mapping,
366 * so while this function is non-blocking, a task will be
367 * left with the scheduler for up to 1s past this call.
369 * @param mini the handle
372 GNUNET_NAT_mini_map_stop (struct GNUNET_NAT_MiniHandle *mini)
378 if (mini->map_cmd != NULL)
380 GNUNET_OS_command_stop (mini->map_cmd);
381 mini->map_cmd = NULL;
386 if (GNUNET_SCHEDULER_NO_TASK != mini->refresh_task)
388 GNUNET_SCHEDULER_cancel (mini->refresh_task);
389 mini->refresh_task = GNUNET_SCHEDULER_NO_TASK;
391 if (mini->refresh_cmd != NULL)
393 GNUNET_OS_command_stop (mini->refresh_cmd);
394 mini->refresh_cmd = NULL;
396 mini->ac (mini->ac_cls, GNUNET_NO,
397 (const struct sockaddr*) &mini->current_addr,
398 sizeof (mini->current_addr));
399 GNUNET_snprintf (pstr, sizeof (pstr),
401 (unsigned int) mini->port);
402 mini->unmap_cmd = GNUNET_OS_command_run (&process_unmap_output,
408 mini->is_tcp ? "tcp" : "udp",
413 /* end of nat_mini.c */