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22 * @file nat/gnunet-service-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_service.h"
29 #include "gnunet-service-nat_mini.h"
32 #define LOG(kind, ...) GNUNET_log_from(kind, "nat", __VA_ARGS__)
35 * How long do we give upnpc to create a mapping?
37 #define MAP_TIMEOUT GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 15)
40 * How long do we give upnpc to remove a mapping?
42 #define UNMAP_TIMEOUT \
43 GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 1)
46 * How often do we check for changes in the mapping?
48 #define MAP_REFRESH_FREQ \
49 GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 5)
52 /* ************************* external-ip calling ************************ */
55 * Opaque handle to cancel "GNUNET_NAT_mini_get_external_ipv4" operation.
57 struct GNUNET_NAT_ExternalHandle {
59 * Function to call with the result.
61 GNUNET_NAT_IPCallback cb;
71 struct GNUNET_SCHEDULER_Task *task;
74 * Handle to `external-ip` process.
76 struct GNUNET_OS_Process *eip;
79 * Handle to stdout pipe of `external-ip`.
81 struct GNUNET_DISK_PipeHandle *opipe;
84 * Read handle of @e opipe.
86 const struct GNUNET_DISK_FileHandle *r;
89 * Number of bytes in @e buf that are valid.
94 * Destination of our read operation (output of 'external-ip').
99 * Error code for better debugging and user feedback
101 enum GNUNET_NAT_StatusCode ret;
106 * Read the output of `external-ip` into `buf`. When complete, parse
107 * the address and call our callback.
109 * @param cls the `struct GNUNET_NAT_ExternalHandle`
112 read_external_ipv4(void *cls)
114 struct GNUNET_NAT_ExternalHandle *eh = cls;
119 ret = GNUNET_DISK_file_read(eh->r,
121 sizeof(eh->buf) - eh->off);
124 /* try to read more */
126 eh->task = GNUNET_SCHEDULER_add_read_file(GNUNET_TIME_UNIT_FOREVER_REL,
132 eh->ret = GNUNET_NAT_ERROR_EXTERNAL_IP_UTILITY_OUTPUT_INVALID;
133 if ((eh->off > 7) && (eh->buf[eh->off - 1] == '\n'))
135 eh->buf[eh->off - 1] = '\0';
136 if (1 == inet_pton(AF_INET, eh->buf, &addr))
138 if (0 == addr.s_addr)
140 GNUNET_NAT_ERROR_EXTERNAL_IP_ADDRESS_INVALID; /* got 0.0.0.0 */
142 eh->ret = GNUNET_NAT_ERROR_SUCCESS;
146 (GNUNET_NAT_ERROR_SUCCESS == eh->ret) ? &addr : NULL,
148 GNUNET_NAT_mini_get_external_ipv4_cancel_(eh);
153 * (Asynchronously) signal error invoking `external-ip` to client.
155 * @param cls the `struct GNUNET_NAT_ExternalHandle` (freed)
158 signal_external_ip_error(void *cls)
160 struct GNUNET_NAT_ExternalHandle *eh = cls;
163 eh->cb(eh->cb_cls, NULL, eh->ret);
169 * Try to get the external IPv4 address of this peer.
171 * @param cb function to call with result
172 * @param cb_cls closure for @a cb
173 * @return handle for cancellation (can only be used until @a cb is called), never NULL
175 struct GNUNET_NAT_ExternalHandle *
176 GNUNET_NAT_mini_get_external_ipv4_(GNUNET_NAT_IPCallback cb, void *cb_cls)
178 struct GNUNET_NAT_ExternalHandle *eh;
180 eh = GNUNET_new(struct GNUNET_NAT_ExternalHandle);
183 eh->ret = GNUNET_NAT_ERROR_SUCCESS;
185 GNUNET_OS_check_helper_binary("external-ip", GNUNET_NO, NULL))
187 LOG(GNUNET_ERROR_TYPE_INFO, _("`external-ip' command not found\n"));
188 eh->ret = GNUNET_NAT_ERROR_EXTERNAL_IP_UTILITY_NOT_FOUND;
189 eh->task = GNUNET_SCHEDULER_add_now(&signal_external_ip_error, eh);
192 LOG(GNUNET_ERROR_TYPE_DEBUG,
193 "Running `external-ip' to determine our external IP\n");
194 eh->opipe = GNUNET_DISK_pipe(GNUNET_YES, GNUNET_YES, GNUNET_NO, GNUNET_YES);
195 if (NULL == eh->opipe)
197 eh->ret = GNUNET_NAT_ERROR_IPC_FAILURE;
198 eh->task = GNUNET_SCHEDULER_add_now(&signal_external_ip_error, eh);
201 eh->eip = GNUNET_OS_start_process(GNUNET_NO,
211 GNUNET_DISK_pipe_close(eh->opipe);
212 eh->ret = GNUNET_NAT_ERROR_EXTERNAL_IP_UTILITY_FAILED;
213 eh->task = GNUNET_SCHEDULER_add_now(&signal_external_ip_error, eh);
216 GNUNET_DISK_pipe_close_end(eh->opipe, GNUNET_DISK_PIPE_END_WRITE);
217 eh->r = GNUNET_DISK_pipe_handle(eh->opipe, GNUNET_DISK_PIPE_END_READ);
218 eh->task = GNUNET_SCHEDULER_add_read_file(GNUNET_TIME_UNIT_FOREVER_REL,
229 * @param eh operation to cancel
232 GNUNET_NAT_mini_get_external_ipv4_cancel_(struct GNUNET_NAT_ExternalHandle *eh)
236 (void)GNUNET_OS_process_kill(eh->eip, SIGKILL);
237 GNUNET_break(GNUNET_OK == GNUNET_OS_process_wait(eh->eip));
238 GNUNET_OS_process_destroy(eh->eip);
240 if (NULL != eh->opipe)
242 GNUNET_DISK_pipe_close(eh->opipe);
245 if (NULL != eh->task)
247 GNUNET_SCHEDULER_cancel(eh->task);
254 /* ************************* upnpc calling ************************ */
258 * Handle to a mapping created with upnpc.
260 struct GNUNET_NAT_MiniHandle {
262 * Function to call on mapping changes.
264 GNUNET_NAT_MiniAddressCallback ac;
272 * Command used to install the map.
274 struct GNUNET_OS_CommandHandle *map_cmd;
277 * Command used to refresh our map information.
279 struct GNUNET_OS_CommandHandle *refresh_cmd;
282 * Command used to remove the mapping.
284 struct GNUNET_OS_CommandHandle *unmap_cmd;
287 * Our current external mapping (if we have one).
289 struct sockaddr_in current_addr;
292 * We check the mapping periodically to see if it
293 * still works. This task triggers the check.
295 struct GNUNET_SCHEDULER_Task *refresh_task;
298 * Are we mapping TCP or UDP?
303 * Did we succeed with creating a mapping?
308 * Did we find our mapping during refresh scan?
313 * Which port are we mapping?
320 * Run "upnpc -l" to find out if our mapping changed.
322 * @param cls the `struct GNUNET_NAT_MiniHandle`
325 do_refresh(void *cls);
329 * Process the output from the "upnpc -r" command.
331 * @param cls the `struct GNUNET_NAT_MiniHandle`
332 * @param line line of output, NULL at the end
335 process_map_output(void *cls, const char *line);
339 * Run "upnpc -r" to map our internal port.
341 * @param mini our handle
344 run_upnpc_r(struct GNUNET_NAT_MiniHandle *mini)
348 GNUNET_snprintf(pstr, sizeof(pstr), "%u", (unsigned int)mini->port);
349 mini->map_cmd = GNUNET_OS_command_run(&process_map_output,
356 mini->is_tcp ? "tcp" : "udp",
358 if (NULL == mini->map_cmd)
360 mini->ac(mini->ac_cls,
364 GNUNET_NAT_ERROR_UPNPC_FAILED);
371 * Process the output from "upnpc -l" to see if our
372 * external mapping changed. If so, do the notifications.
374 * @param cls the `struct GNUNET_NAT_MiniHandle`
375 * @param line line of output, NULL at the end
378 process_refresh_output(void *cls, const char *line)
380 struct GNUNET_NAT_MiniHandle *mini = cls;
388 GNUNET_OS_command_stop(mini->refresh_cmd);
389 mini->refresh_cmd = NULL;
390 if (GNUNET_NO == mini->found)
392 /* mapping disappeared, try to re-create */
393 if (GNUNET_YES == mini->did_map)
395 mini->ac(mini->ac_cls,
397 (const struct sockaddr *)&mini->current_addr,
398 sizeof(mini->current_addr),
399 GNUNET_NAT_ERROR_SUCCESS);
400 mini->did_map = GNUNET_NO;
407 return; /* never mapped, won't find our mapping anyway */
409 /* we're looking for output of the form:
410 * "ExternalIPAddress = 12.134.41.124" */
412 s = strstr(line, "ExternalIPAddress = ");
415 s += strlen("ExternalIPAddress = ");
416 if (1 != inet_pton(AF_INET, s, &exip))
418 if (exip.s_addr == mini->current_addr.sin_addr.s_addr)
419 return; /* no change */
421 mini->ac(mini->ac_cls,
423 (const struct sockaddr *)&mini->current_addr,
424 sizeof(mini->current_addr),
425 GNUNET_NAT_ERROR_SUCCESS);
426 mini->current_addr.sin_addr = exip;
427 mini->ac(mini->ac_cls,
429 (const struct sockaddr *)&mini->current_addr,
430 sizeof(mini->current_addr),
431 GNUNET_NAT_ERROR_SUCCESS);
435 * we're looking for output of the form:
437 * "0 TCP 3000->192.168.2.150:3000 'libminiupnpc' ''"
438 * "1 UDP 3001->192.168.2.150:3001 'libminiupnpc' ''"
440 * the pattern we look for is:
442 * "%s TCP PORT->STRING:OURPORT *" or
443 * "%s UDP PORT->STRING:OURPORT *"
445 GNUNET_snprintf(pstr, sizeof(pstr), ":%u ", mini->port);
446 if (NULL == (s = strstr(line, "->")))
448 if (NULL == strstr(s, pstr))
450 if (1 != sscanf(line,
451 (mini->is_tcp) ? "%*u TCP %u->%*s:%*u %*s"
452 : "%*u UDP %u->%*s:%*u %*s",
455 mini->found = GNUNET_YES;
456 if (nport == ntohs(mini->current_addr.sin_port))
457 return; /* no change */
459 /* external port changed, update mapping */
460 mini->ac(mini->ac_cls,
462 (const struct sockaddr *)&mini->current_addr,
463 sizeof(mini->current_addr),
464 GNUNET_NAT_ERROR_SUCCESS);
465 mini->current_addr.sin_port = htons((uint16_t)nport);
466 mini->ac(mini->ac_cls,
468 (const struct sockaddr *)&mini->current_addr,
469 sizeof(mini->current_addr),
470 GNUNET_NAT_ERROR_SUCCESS);
475 * Run "upnpc -l" to find out if our mapping changed.
477 * @param cls the 'struct GNUNET_NAT_MiniHandle'
480 do_refresh(void *cls)
482 struct GNUNET_NAT_MiniHandle *mini = cls;
486 GNUNET_SCHEDULER_add_delayed(MAP_REFRESH_FREQ, &do_refresh, mini);
487 LOG(GNUNET_ERROR_TYPE_DEBUG,
488 "Running `upnpc' to check if our mapping still exists\n");
489 mini->found = GNUNET_NO;
491 if (NULL != mini->map_cmd)
493 /* took way too long, abort it! */
494 GNUNET_OS_command_stop(mini->map_cmd);
495 mini->map_cmd = NULL;
498 if (NULL != mini->refresh_cmd)
500 /* took way too long, abort it! */
501 GNUNET_OS_command_stop(mini->refresh_cmd);
502 mini->refresh_cmd = NULL;
505 mini->refresh_cmd = GNUNET_OS_command_run(&process_refresh_output,
512 if (GNUNET_YES == ac)
513 mini->ac(mini->ac_cls,
517 GNUNET_NAT_ERROR_UPNPC_TIMEOUT);
522 * Process the output from the 'upnpc -r' command.
524 * @param cls the `struct GNUNET_NAT_MiniHandle`
525 * @param line line of output, NULL at the end
528 process_map_output(void *cls, const char *line)
530 struct GNUNET_NAT_MiniHandle *mini = cls;
538 GNUNET_OS_command_stop(mini->map_cmd);
539 mini->map_cmd = NULL;
540 if (GNUNET_YES != mini->did_map)
541 mini->ac(mini->ac_cls,
545 GNUNET_NAT_ERROR_UPNPC_PORTMAP_FAILED);
546 if (NULL == mini->refresh_task)
548 GNUNET_SCHEDULER_add_delayed(MAP_REFRESH_FREQ, &do_refresh, mini);
552 * The upnpc output we're after looks like this:
554 * "external 87.123.42.204:3000 TCP is redirected to internal 192.168.2.150:3000"
556 if ((NULL == (ipaddr = strstr(line, " "))) ||
557 (NULL == (pstr = strstr(ipaddr, ":"))) ||
558 (1 != sscanf(pstr + 1, "%u", &port)))
560 return; /* skip line */
562 ipa = GNUNET_strdup(ipaddr + 1);
563 strstr(ipa, ":")[0] = '\0';
564 if (1 != inet_pton(AF_INET, ipa, &mini->current_addr.sin_addr))
567 return; /* skip line */
571 mini->current_addr.sin_port = htons(port);
572 mini->current_addr.sin_family = AF_INET;
573 #if HAVE_SOCKADDR_IN_SIN_LEN
574 mini->current_addr.sin_len = sizeof(struct sockaddr_in);
576 mini->did_map = GNUNET_YES;
577 mini->ac(mini->ac_cls,
579 (const struct sockaddr *)&mini->current_addr,
580 sizeof(mini->current_addr),
581 GNUNET_NAT_ERROR_SUCCESS);
586 * Start mapping the given port using (mini)upnpc. This function
587 * should typically not be used directly (it is used within the
588 * general-purpose #GNUNET_NAT_register() code). However, it can be
589 * used if specifically UPnP-based NAT traversal is to be used or
592 * @param port port to map
593 * @param is_tcp #GNUNET_YES to map TCP, #GNUNET_NO for UDP
594 * @param ac function to call with mapping result
595 * @param ac_cls closure for @a ac
596 * @return NULL on error (no 'upnpc' installed)
598 struct GNUNET_NAT_MiniHandle *
599 GNUNET_NAT_mini_map_start(uint16_t port,
601 GNUNET_NAT_MiniAddressCallback ac,
604 struct GNUNET_NAT_MiniHandle *ret;
606 if (GNUNET_SYSERR == GNUNET_OS_check_helper_binary("upnpc", GNUNET_NO, NULL))
608 LOG(GNUNET_ERROR_TYPE_INFO, _("`upnpc' command not found\n"));
609 ac(ac_cls, GNUNET_SYSERR, NULL, 0, GNUNET_NAT_ERROR_UPNPC_NOT_FOUND);
612 LOG(GNUNET_ERROR_TYPE_DEBUG, "Running `upnpc' to install mapping\n");
613 ret = GNUNET_new(struct GNUNET_NAT_MiniHandle);
615 ret->ac_cls = ac_cls;
616 ret->is_tcp = is_tcp;
619 GNUNET_SCHEDULER_add_delayed(MAP_REFRESH_FREQ, &do_refresh, ret);
626 * Process output from our 'unmap' command.
628 * @param cls the `struct GNUNET_NAT_MiniHandle`
629 * @param line line of output, NULL at the end
632 process_unmap_output(void *cls, const char *line)
634 struct GNUNET_NAT_MiniHandle *mini = cls;
638 LOG(GNUNET_ERROR_TYPE_DEBUG, "UPnP unmap done\n");
639 GNUNET_OS_command_stop(mini->unmap_cmd);
640 mini->unmap_cmd = NULL;
644 /* we don't really care about the output... */
649 * Remove a mapping created with (mini)upnpc. Calling
650 * this function will give 'upnpc' 1s to remove tha mapping,
651 * so while this function is non-blocking, a task will be
652 * left with the scheduler for up to 1s past this call.
654 * @param mini the handle
657 GNUNET_NAT_mini_map_stop(struct GNUNET_NAT_MiniHandle *mini)
661 if (NULL != mini->refresh_task)
663 GNUNET_SCHEDULER_cancel(mini->refresh_task);
664 mini->refresh_task = NULL;
666 if (NULL != mini->refresh_cmd)
668 GNUNET_OS_command_stop(mini->refresh_cmd);
669 mini->refresh_cmd = NULL;
671 if (NULL != mini->map_cmd)
673 GNUNET_OS_command_stop(mini->map_cmd);
674 mini->map_cmd = NULL;
676 if (GNUNET_NO == mini->did_map)
681 mini->ac(mini->ac_cls,
683 (const struct sockaddr *)&mini->current_addr,
684 sizeof(mini->current_addr),
685 GNUNET_NAT_ERROR_SUCCESS);
686 /* Note: oddly enough, deletion uses the external port whereas
687 * addition uses the internal port; this rarely matters since they
688 * often are the same, but it might... */
689 GNUNET_snprintf(pstr,
692 (unsigned int)ntohs(mini->current_addr.sin_port));
693 LOG(GNUNET_ERROR_TYPE_DEBUG,
694 "Unmapping port %u with UPnP\n",
695 ntohs(mini->current_addr.sin_port));
696 mini->unmap_cmd = GNUNET_OS_command_run(&process_unmap_output,
703 mini->is_tcp ? "tcp" : "udp",
708 /* end of gnunet-service-nat_mini.c */