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22 * @file nat/nat_auto.c
23 * @brief functions for auto-configuration of the network
24 * @author Christian Grothoff
25 * @author Bruno Cabral
28 #include "gnunet_util_lib.h"
29 #include "gnunet_resolver_service.h"
30 #include "gnunet_nat_lib.h"
33 #define LOG(kind,...) GNUNET_log_from (kind, "nat", __VA_ARGS__)
37 * How long do we wait for the NAT test to report success?
39 #define TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15)
41 #define NAT_SERVER_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 10)
44 * Phases of the auto configuration.
49 * Initial start value.
54 * Test our external IP.
59 * Test our external IP.
64 * Test our internal IP.
69 * Test if NAT was punched.
74 * Test if UPnP is working.
79 * Test if ICMP server works.
84 * Test if ICMP client works.
89 * Last phase, we're done.
97 * Handle to auto-configuration in progress.
99 struct GNUNET_NAT_AutoHandle
103 * Handle to the active NAT test.
105 struct GNUNET_NAT_Test *tst;
108 * Function to call when done.
110 GNUNET_NAT_AutoResultCallback fin_cb;
113 * Closure for @e fin_cb.
118 * Handle for active 'GNUNET_NAT_mini_get_external_ipv4'-operation.
120 struct GNUNET_NAT_ExternalHandle *eh;
123 * Current configuration (with updates from previous phases)
125 struct GNUNET_CONFIGURATION_Handle *cfg;
128 * Original configuration (used to calculate differences)
130 struct GNUNET_CONFIGURATION_Handle *initial_cfg;
133 * Task identifier for the timeout.
135 struct GNUNET_SCHEDULER_Task * task;
138 * Where are we in the test?
140 enum AutoPhase phase;
144 * Situation of the NAT
146 enum GNUNET_NAT_Type type;
154 * UPnP already set the external ip address ?
156 int upnp_set_external_address;
159 * Did the external server connected back ?
164 * Address detected by STUN
170 * Internal IP is the same as the public one ?
172 int internal_ip_is_public;
175 * Error code for better debugging and user feedback
177 enum GNUNET_NAT_StatusCode ret;
186 * The listen socket of the service for IPv4
188 static struct GNUNET_NETWORK_Handle *lsock4;
192 * The listen task ID for IPv4
194 static struct GNUNET_SCHEDULER_Task * ltask4;
200 * The port the test service is running on (default 7895)
202 static unsigned long long port = 7895;
204 static char *stun_server = "stun.ekiga.net";
205 static int stun_port = 3478;
210 * Run the next phase of the auto test.
212 * @param ah auto test handle
215 next_phase (struct GNUNET_NAT_AutoHandle *ah);
221 process_stun_reply(struct sockaddr_in* answer, struct GNUNET_NAT_AutoHandle *ah)
224 ah->stun_ip = inet_ntoa(answer->sin_addr);
225 ah->stun_port = ntohs(answer->sin_port);
226 GNUNET_log (GNUNET_ERROR_TYPE_INFO, "External IP is: %s , with port %d\n", ah->stun_ip, ah->stun_port);
234 * Function that terminates the test.
239 GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Stopping STUN and quitting...\n");
244 GNUNET_SCHEDULER_cancel (ltask4);
251 GNUNET_NETWORK_socket_close (lsock4);
257 * Activity on our incoming socket. Read data from the
258 * incoming connection.
263 do_udp_read (void *cls)
265 struct GNUNET_NAT_AutoHandle *ah = cls;
266 unsigned char reply_buf[1024];
268 struct sockaddr_in answer;
269 const struct GNUNET_SCHEDULER_TaskContext *tc;
271 tc = GNUNET_SCHEDULER_get_task_context ();
272 if ((0 != (tc->reason & GNUNET_SCHEDULER_REASON_READ_READY)) &&
273 (GNUNET_NETWORK_fdset_isset (tc->read_ready,
276 rlen = GNUNET_NETWORK_socket_recv (lsock4,
280 //Lets handle the packet
281 memset(&answer, 0, sizeof(struct sockaddr_in));
282 if(ah->phase == AUTO_NAT_PUNCHED)
284 //Destroy the connection
285 GNUNET_NETWORK_socket_close (lsock4);
286 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
287 "The external server was able to connect back");
288 ah->connected_back = GNUNET_YES;
294 GNUNET_NAT_stun_handle_packet (reply_buf, rlen, &answer))
297 process_stun_reply (&answer, ah);
307 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
308 "TIMEOUT while waiting for an answer\n");
309 if (ah->phase == AUTO_NAT_PUNCHED)
320 * Create an IPv4 listen socket bound to our port.
322 * @return NULL on error
324 static struct GNUNET_NETWORK_Handle *
327 struct GNUNET_NETWORK_Handle *ls;
328 struct sockaddr_in sa4;
331 memset (&sa4, 0, sizeof (sa4));
332 sa4.sin_family = AF_INET;
333 sa4.sin_port = htons (port);
334 #if HAVE_SOCKADDR_IN_SIN_LEN
335 sa4.sin_len = sizeof (sa4);
337 ls = GNUNET_NETWORK_socket_create (AF_INET,
343 GNUNET_NETWORK_socket_bind (ls, (const struct sockaddr *) &sa4,
347 GNUNET_NETWORK_socket_close (ls);
356 request_callback (void *cls,
357 enum GNUNET_NAT_StatusCode result)
359 // struct GNUNET_NAT_AutoHandle *ah = cls;
361 GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Request callback: stop and quit\n");
364 // next_phase (ah); FIXME this always will be NULL, as called in test_stun()
369 * Function called by NAT to report the outcome of the nat-test.
370 * Clean up and update GUI.
372 * @param cls the auto handle
373 * @param success currently always #GNUNET_OK
374 * @param emsg NULL on success, otherwise an error message
377 result_callback (void *cls,
378 enum GNUNET_NAT_StatusCode ret)
380 struct GNUNET_NAT_AutoHandle *ah = cls;
382 if (GNUNET_NAT_ERROR_SUCCESS == ret)
383 GNUNET_NAT_test_stop (ah->tst);
386 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
387 GNUNET_NAT_ERROR_SUCCESS == ret
388 ? _("NAT traversal with ICMP Server succeeded.\n")
389 : _("NAT traversal with ICMP Server failed.\n"));
390 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "ENABLE_ICMP_SERVER",
391 GNUNET_NAT_ERROR_SUCCESS == ret ? "NO" : "YES");
397 * Main function for the connection reversal test.
399 * @param cls the `struct GNUNET_NAT_AutoHandle`
402 reversal_test (void *cls)
404 struct GNUNET_NAT_AutoHandle *ah = cls;
407 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
408 _("Testing connection reversal with ICMP server.\n"));
409 GNUNET_RESOLVER_connect (ah->cfg);
410 ah->tst = GNUNET_NAT_test_start (ah->cfg, GNUNET_YES, 0, 0, TIMEOUT,
411 &result_callback, ah);
416 * Set our external IPv4 address based on the UPnP.
419 * @param cls closure with our setup context
420 * @param addr the address, NULL on errors
421 * @param emsg NULL on success, otherwise an error message
424 set_external_ipv4 (void *cls,
425 const struct in_addr *addr,
426 enum GNUNET_NAT_StatusCode ret)
428 struct GNUNET_NAT_AutoHandle *ah = cls;
429 char buf[INET_ADDRSTRLEN];
433 if (GNUNET_NAT_ERROR_SUCCESS != ret)
438 /* enable 'behind nat' */
439 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
440 _("Detected external IP `%s'\n"),
445 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "YES");
447 /* set external IP address */
448 if (NULL == inet_ntop (AF_INET, addr, buf, sizeof (buf)))
451 /* actually, this should never happen, as the caller already executed just
452 * this check, but for consistency (eg: future changes in the caller)
453 * we still need to report this error...
455 ah->ret = GNUNET_NAT_ERROR_EXTERNAL_IP_ADDRESS_INVALID;
459 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
461 ah->upnp_set_external_address = GNUNET_YES;
467 * Determine our external IPv4 address.
469 * @param ah auto setup context
472 test_external_ip (struct GNUNET_NAT_AutoHandle *ah)
474 if (GNUNET_NAT_ERROR_SUCCESS != ah->ret)
478 /* try to detect external IP */
479 ah->eh = GNUNET_NAT_mini_get_external_ipv4 (TIMEOUT,
480 &set_external_ipv4, ah);
485 * Determine our external IPv4 address and port using an external STUN server
487 * @param ah auto setup context
490 test_stun (struct GNUNET_NAT_AutoHandle *ah)
493 GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Running STUN test\n");
495 /* Get port from the configuration */
497 GNUNET_CONFIGURATION_get_value_number (ah->cfg,
505 //Lets create the socket
509 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "bind");
515 //Lets call our function now when it accepts
516 ltask4 = GNUNET_SCHEDULER_add_read_net (NAT_SERVER_TIMEOUT,
523 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
524 "STUN service listens on port %u\n",
525 (unsigned int) port);
527 GNUNET_NAT_stun_make_request (stun_server, stun_port,
532 /*An error happened*/
533 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "STUN error, stopping\n");
541 * Process list of local IP addresses. Find and set the
542 * one of the default interface.
544 * @param cls our `struct GNUNET_NAT_AutoHandle`
545 * @param name name of the interface (can be NULL for unknown)
546 * @param isDefault is this presumably the default interface
547 * @param addr address of this interface (can be NULL for unknown or unassigned)
548 * @param broadcast_addr the broadcast address (can be NULL for unknown or unassigned)
549 * @param netmask the network mask (can be NULL for unknown or unassigned))
550 * @param addrlen length of the @a addr and @a broadcast_addr
551 * @return #GNUNET_OK to continue iteration, #GNUNET_SYSERR to abort
554 process_if (void *cls,
557 const struct sockaddr *addr,
558 const struct sockaddr *broadcast_addr,
559 const struct sockaddr *netmask,
562 struct GNUNET_NAT_AutoHandle *ah = cls;
563 const struct sockaddr_in *in;
564 char buf[INET_ADDRSTRLEN];
567 if ( (sizeof (struct sockaddr_in6) == addrlen) &&
568 (0 != memcmp (&in6addr_loopback, &((const struct sockaddr_in6 *) addr)->sin6_addr,
569 sizeof (struct in6_addr))) &&
570 (! IN6_IS_ADDR_LINKLOCAL(&((const struct sockaddr_in6 *) addr)->sin6_addr)) )
572 ah->have_v6 = GNUNET_YES;
573 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
574 _("This system has a global IPv6 address, setting IPv6 to supported.\n"));
578 if (addrlen != sizeof (struct sockaddr_in))
580 in = (const struct sockaddr_in *) addr;
583 /* set internal IP address */
584 if (NULL == inet_ntop (AF_INET, &in->sin_addr, buf, sizeof (buf)))
589 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "INTERNAL_ADDRESS",
591 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
592 _("Detected internal network address `%s'.\n"),
596 ah->ret = GNUNET_NAT_ERROR_SUCCESS;
598 /* Check if our internal IP is the same as the External detect by STUN*/
599 if(ah->stun_ip && (strcmp(buf, ah->stun_ip) == 0) )
601 ah->internal_ip_is_public = GNUNET_YES;
602 GNUNET_log (GNUNET_ERROR_TYPE_INFO,"A internal IP is the sameas the external");
603 /* No need to continue*/
604 return GNUNET_SYSERR;
607 /* no need to continue iteration if we found the default */
611 return GNUNET_SYSERR;
616 * Determine our local IP addresses; detect internal IP & IPv6-support
618 * @param ah auto setup context
621 test_local_ip (struct GNUNET_NAT_AutoHandle *ah)
623 ah->have_v6 = GNUNET_NO;
624 ah->ret = GNUNET_NAT_ERROR_NO_VALID_IF_IP_COMBO; // reset to success if any of the IFs in below iterator has a valid IP
625 GNUNET_OS_network_interfaces_list (&process_if, ah);
627 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "DISABLEV6",
628 (GNUNET_YES == ah->have_v6) ? "NO" : "YES");
634 * Test if NAT has been punched
636 * @param ah auto setup context
639 test_nat_punched (struct GNUNET_NAT_AutoHandle *ah)
641 struct GNUNET_CLIENT_Connection *client;
642 struct GNUNET_NAT_TestMessage msg;
646 LOG (GNUNET_ERROR_TYPE_INFO,
647 "Asking gnunet-nat-server to connect to `%s'\n",
651 msg.header.size = htons (sizeof (struct GNUNET_NAT_TestMessage));
652 msg.header.type = htons (GNUNET_MESSAGE_TYPE_NAT_TEST);
653 msg.dst_ipv4 = inet_addr(ah->stun_ip);
654 msg.dport = htons(ah->stun_port);
656 msg.is_tcp = htonl ((uint32_t) GNUNET_NO);
658 client = GNUNET_CLIENT_connect ("gnunet-nat-server", ah->cfg);
661 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
662 _("Failed to connect to `gnunet-nat-server'\n"));
666 GNUNET_break (GNUNET_OK ==
667 GNUNET_CLIENT_transmit_and_get_response (client, &msg.header,
673 GNUNET_SCHEDULER_cancel (ltask4);
674 ltask4 = GNUNET_SCHEDULER_add_read_net (NAT_SERVER_TIMEOUT,
682 LOG (GNUNET_ERROR_TYPE_INFO,
683 "We don't have a STUN IP");
690 * Test if UPnPC works.
692 * @param ah auto setup context
695 test_upnpc (struct GNUNET_NAT_AutoHandle *ah)
700 if (GNUNET_NAT_ERROR_SUCCESS != ah->ret)
703 // test if upnpc is available
704 have_upnpc = (GNUNET_SYSERR !=
705 GNUNET_OS_check_helper_binary ("upnpc", GNUNET_NO, NULL));
706 //FIXME: test if upnpc is actually working, that is, if transports start to work once we use UPnP
707 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
709 ? _("upnpc found, enabling its use\n")
710 : _("upnpc not found\n"));
711 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "ENABLE_UPNP",
712 (GNUNET_YES == have_upnpc) ? "YES" : "NO");
719 * Test if ICMP server is working
721 * @param ah auto setup context
724 test_icmp_server (struct GNUNET_NAT_AutoHandle *ah)
737 helper = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-nat-server");
739 GNUNET_CONFIGURATION_get_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
740 &tmp)) && (0 < strlen (tmp))){
742 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("test_icmp_server not possible, as we have no public IPv4 address\n"));
748 GNUNET_CONFIGURATION_get_value_yesno (ah->cfg, "nat", "BEHIND_NAT")){
750 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("test_icmp_server not possible, as we are not behind NAT\n"));
756 GNUNET_OS_check_helper_binary (helper, GNUNET_YES, "-d 127.0.0.1" )){
757 binary = GNUNET_OK; // use localhost as source for that one udp-port, ok for testing
758 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("No working gnunet-helper-nat-server found\n"));
761 GNUNET_free_non_null (tmp);
762 GNUNET_free (helper);
764 if (GNUNET_OK == ext_ip && GNUNET_YES == nated && GNUNET_OK == binary)
765 ah->task = GNUNET_SCHEDULER_add_now (&reversal_test, ah);
772 * Test if ICMP client is working
774 * @param ah auto setup context
777 test_icmp_client (struct GNUNET_NAT_AutoHandle *ah)
783 helper = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-nat-client");
785 GNUNET_CONFIGURATION_get_value_string (ah->cfg, "nat", "INTERNAL_ADDRESS",
786 &tmp)) && (0 < strlen (tmp)))
788 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("test_icmp_client not possible, as we have no internal IPv4 address\n"));
794 GNUNET_CONFIGURATION_get_value_yesno (ah->cfg, "nat", "BEHIND_NAT")){
795 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
796 _("test_icmp_server not possible, as we are not behind NAT\n"));
802 GNUNET_OS_check_helper_binary (helper, GNUNET_YES, "-d 127.0.0.1 127.0.0.2 42")){
803 // none of these parameters are actually used in privilege testing mode
804 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
805 _("No working gnunet-helper-nat-server found\n"));
808 GNUNET_free_non_null (tmp);
809 GNUNET_free (helper);
816 * Run the next phase of the auto test.
819 next_phase (struct GNUNET_NAT_AutoHandle *ah)
821 struct GNUNET_CONFIGURATION_Handle *diff;
829 case AUTO_EXTERNAL_IP:
830 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_EXTERNAL_IP\n");
831 test_external_ip (ah);
834 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_STUN\n");
838 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_LOCAL_IP\n");
841 case AUTO_NAT_PUNCHED:
842 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_NAT_PUNCHED\n");
843 test_nat_punched (ah);
846 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_UPNPC\n");
849 case AUTO_ICMP_SERVER:
850 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_ICMP_SERVER\n");
851 test_icmp_server (ah);
853 case AUTO_ICMP_CLIENT:
854 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_ICMP_CLIENT\n");
855 test_icmp_client (ah);
858 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Done with tests\n");
859 if (!ah->internal_ip_is_public)
861 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "YES");
863 if (ah->connected_back)
865 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "PUNCHED_NAT", "YES");
869 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "PUNCHED_NAT", "NO");
874 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
876 if (ah->connected_back)
878 ah->type = GNUNET_NAT_TYPE_STUN_PUNCHED_NAT;
879 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "USE_STUN", "YES");
883 ah->type = GNUNET_NAT_TYPE_UNREACHABLE_NAT;
884 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "USE_STUN", "NO");
890 GNUNET_CONFIGURATION_set_value_number (ah->cfg, "transport-udp",
898 //The internal IP is the same as public, but we didn't got a incoming connection
899 if (ah->connected_back)
901 ah->type = GNUNET_NAT_TYPE_NO_NAT;
902 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "NO");
906 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "YES");
907 ah->type = GNUNET_NAT_TYPE_UNREACHABLE_NAT;
910 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
915 GNUNET_CONFIGURATION_set_value_number (ah->cfg, "transport-udp",
923 diff = GNUNET_CONFIGURATION_get_diff (ah->initial_cfg,
927 ah->fin_cb (ah->fin_cb_cls,
931 GNUNET_CONFIGURATION_destroy (diff);
932 GNUNET_NAT_autoconfig_cancel (ah);
939 * Start auto-configuration routine. The resolver service should
940 * be available when this function is called.
942 * @param cfg initial configuration
943 * @param cb function to call with autoconfiguration result
944 * @param cb_cls closure for @a cb
945 * @return handle to cancel operation
947 struct GNUNET_NAT_AutoHandle *
948 GNUNET_NAT_autoconfig_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
949 GNUNET_NAT_AutoResultCallback cb,
952 struct GNUNET_NAT_AutoHandle *ah;
954 ah = GNUNET_new (struct GNUNET_NAT_AutoHandle);
956 ah->fin_cb_cls = cb_cls;
957 ah->ret = GNUNET_NAT_ERROR_SUCCESS;
958 ah->cfg = GNUNET_CONFIGURATION_dup (cfg);
959 ah->initial_cfg = GNUNET_CONFIGURATION_dup (cfg);
961 /* never use loopback addresses if user wanted autoconfiguration */
962 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat",
972 * Abort autoconfiguration.
974 * @param ah handle for operation to abort
977 GNUNET_NAT_autoconfig_cancel (struct GNUNET_NAT_AutoHandle *ah)
981 GNUNET_NAT_test_stop (ah->tst);
986 GNUNET_NAT_mini_get_external_ipv4_cancel (ah->eh);
989 if (NULL != ah->task)
991 GNUNET_SCHEDULER_cancel (ah->task);
994 GNUNET_CONFIGURATION_destroy (ah->cfg);
995 GNUNET_CONFIGURATION_destroy (ah->initial_cfg);
1000 /* end of nat_auto.c */