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3 Copyright (C) 2015 Christian Grothoff (and other contributing authors)
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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 NAT and quitting...\n");
243 GNUNET_SCHEDULER_cancel (ltask4);
247 GNUNET_NETWORK_socket_close (lsock4);
252 * Activity on our incoming socket. Read data from the
253 * incoming connection.
256 * @param tc scheduler context
259 do_udp_read (void *cls,
260 const struct GNUNET_SCHEDULER_TaskContext *tc)
262 struct GNUNET_NAT_AutoHandle *ah = cls;
263 unsigned char reply_buf[1024];
265 struct sockaddr_in answer;
268 if ((0 != (tc->reason & GNUNET_SCHEDULER_REASON_READ_READY)) &&
269 (GNUNET_NETWORK_fdset_isset (tc->read_ready,
272 rlen = GNUNET_NETWORK_socket_recv (lsock4, reply_buf, sizeof (reply_buf));
275 //Lets handle the packet
276 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, "The external server was able to connect back");
287 ah->connected_back = GNUNET_YES;
292 if(GNUNET_OK == GNUNET_NAT_stun_handle_packet(reply_buf,rlen, &answer))
295 process_stun_reply(&answer, ah);
308 GNUNET_log (GNUNET_ERROR_TYPE_INFO, "TIMEOUT while aiting for an answer");
309 if(ah->phase == AUTO_NAT_PUNCHED)
323 * Create an IPv4 listen socket bound to our port.
325 * @return NULL on error
327 static struct GNUNET_NETWORK_Handle *
330 struct GNUNET_NETWORK_Handle *ls;
331 struct sockaddr_in sa4;
334 memset (&sa4, 0, sizeof (sa4));
335 sa4.sin_family = AF_INET;
336 sa4.sin_port = htons (port);
337 #if HAVE_SOCKADDR_IN_SIN_LEN
338 sa4.sin_len = sizeof (sa4);
340 ls = GNUNET_NETWORK_socket_create (AF_INET,
346 GNUNET_NETWORK_socket_bind (ls, (const struct sockaddr *) &sa4,
350 GNUNET_NETWORK_socket_close (ls);
360 static void request_callback(void *cls,
361 enum GNUNET_NAT_StatusCode result)
363 struct GNUNET_NAT_AutoHandle *ah = cls;
364 GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Stopping NAT and quitting...\n");
375 * Function called by NAT to report the outcome of the nat-test.
376 * Clean up and update GUI.
378 * @param cls the auto handle
379 * @param success currently always #GNUNET_OK
380 * @param emsg NULL on success, otherwise an error message
383 result_callback (void *cls,
384 enum GNUNET_NAT_StatusCode ret)
386 struct GNUNET_NAT_AutoHandle *ah = cls;
388 if (GNUNET_NAT_ERROR_SUCCESS == ret)
389 GNUNET_NAT_test_stop (ah->tst);
392 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
393 GNUNET_NAT_ERROR_SUCCESS == ret
394 ? _("NAT traversal with ICMP Server succeeded.\n")
395 : _("NAT traversal with ICMP Server failed.\n"));
396 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "ENABLE_ICMP_SERVER",
397 GNUNET_NAT_ERROR_SUCCESS == ret ? "NO" : "YES");
403 * Main function for the connection reversal test.
405 * @param cls the `struct GNUNET_NAT_AutoHandle`
406 * @param tc scheduler context
409 reversal_test (void *cls,
410 const struct GNUNET_SCHEDULER_TaskContext *tc)
412 struct GNUNET_NAT_AutoHandle *ah = cls;
415 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
416 _("Testing connection reversal with ICMP server.\n"));
417 GNUNET_RESOLVER_connect (ah->cfg);
418 ah->tst = GNUNET_NAT_test_start (ah->cfg, GNUNET_YES, 0, 0, TIMEOUT,
419 &result_callback, ah);
424 * Set our external IPv4 address based on the UPnP.
427 * @param cls closure with our setup context
428 * @param addr the address, NULL on errors
429 * @param emsg NULL on success, otherwise an error message
432 set_external_ipv4 (void *cls,
433 const struct in_addr *addr,
434 enum GNUNET_NAT_StatusCode ret)
436 struct GNUNET_NAT_AutoHandle *ah = cls;
437 char buf[INET_ADDRSTRLEN];
441 if (GNUNET_NAT_ERROR_SUCCESS != ret)
446 /* enable 'behind nat' */
447 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
448 _("Detected external IP `%s'\n"),
453 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "YES");
455 /* set external IP address */
456 if (NULL == inet_ntop (AF_INET, addr, buf, sizeof (buf)))
459 /* actually, this should never happen, as the caller already executed just
460 * this check, but for consistency (eg: future changes in the caller)
461 * we still need to report this error...
463 ah->ret = GNUNET_NAT_ERROR_EXTERNAL_IP_ADDRESS_INVALID;
467 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
469 ah->upnp_set_external_address = GNUNET_YES;
475 * Determine our external IPv4 address.
477 * @param ah auto setup context
480 test_external_ip (struct GNUNET_NAT_AutoHandle *ah)
482 if (GNUNET_NAT_ERROR_SUCCESS != ah->ret)
486 /* try to detect external IP */
487 ah->eh = GNUNET_NAT_mini_get_external_ipv4 (TIMEOUT,
488 &set_external_ipv4, ah);
493 * Determine our external IPv4 address and port using an external STUN server
495 * @param ah auto setup context
498 test_stun (struct GNUNET_NAT_AutoHandle *ah)
501 GNUNET_log (GNUNET_ERROR_TYPE_INFO,"Running STUN test");
503 /* Get port from the configuration */
505 GNUNET_CONFIGURATION_get_value_number (ah->cfg,
513 //Lets create the socket
517 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "bind");
523 //Lets call our function now when it accepts
524 ltask4 = GNUNET_SCHEDULER_add_read_net (NAT_SERVER_TIMEOUT,
525 lsock4, &do_udp_read, ah);
530 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
531 "STUN service listens on port %u\n",
533 if( GNUNET_NO == GNUNET_NAT_stun_make_request(stun_server, stun_port, lsock4, &request_callback, NULL))
535 /*An error happened*/
546 * Process list of local IP addresses. Find and set the
547 * one of the default interface.
549 * @param cls our `struct GNUNET_NAT_AutoHandle`
550 * @param name name of the interface (can be NULL for unknown)
551 * @param isDefault is this presumably the default interface
552 * @param addr address of this interface (can be NULL for unknown or unassigned)
553 * @param broadcast_addr the broadcast address (can be NULL for unknown or unassigned)
554 * @param netmask the network mask (can be NULL for unknown or unassigned))
555 * @param addrlen length of the @a addr and @a broadcast_addr
556 * @return GNUNET_OK to continue iteration, #GNUNET_SYSERR to abort
559 process_if (void *cls,
562 const struct sockaddr *addr,
563 const struct sockaddr *broadcast_addr,
564 const struct sockaddr *netmask,
567 struct GNUNET_NAT_AutoHandle *ah = cls;
568 const struct sockaddr_in *in;
569 char buf[INET_ADDRSTRLEN];
572 if ( (sizeof (struct sockaddr_in6) == addrlen) &&
573 (0 != memcmp (&in6addr_loopback, &((const struct sockaddr_in6 *) addr)->sin6_addr,
574 sizeof (struct in6_addr))) &&
575 (! IN6_IS_ADDR_LINKLOCAL(&((const struct sockaddr_in6 *) addr)->sin6_addr)) )
577 ah->have_v6 = GNUNET_YES;
578 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
579 _("This system has a global IPv6 address, setting IPv6 to supported.\n"));
583 if (addrlen != sizeof (struct sockaddr_in))
585 in = (const struct sockaddr_in *) addr;
588 /* set internal IP address */
589 if (NULL == inet_ntop (AF_INET, &in->sin_addr, buf, sizeof (buf)))
594 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "INTERNAL_ADDRESS",
596 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
597 _("Detected internal network address `%s'.\n"),
601 ah->ret = GNUNET_NAT_ERROR_SUCCESS;
603 /* Check if our internal IP is the same as the External detect by STUN*/
604 if(ah->stun_ip && (strcmp(buf, ah->stun_ip) == 0) )
606 ah->internal_ip_is_public = GNUNET_YES;
607 GNUNET_log (GNUNET_ERROR_TYPE_INFO,"A internal IP is the sameas the external");
608 /* No need to continue*/
609 return GNUNET_SYSERR;
612 /* no need to continue iteration if we found the default */
616 return GNUNET_SYSERR;
621 * Determine our local IP addresses; detect internal IP & IPv6-support
623 * @param ah auto setup context
626 test_local_ip (struct GNUNET_NAT_AutoHandle *ah)
628 ah->have_v6 = GNUNET_NO;
629 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
630 GNUNET_OS_network_interfaces_list (&process_if, ah);
632 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "DISABLEV6",
633 (GNUNET_YES == ah->have_v6) ? "NO" : "YES");
639 * Test if NAT has been punched
641 * @param ah auto setup context
644 test_nat_punched (struct GNUNET_NAT_AutoHandle *ah)
647 struct GNUNET_CLIENT_Connection *client;
648 struct GNUNET_NAT_TestMessage msg;
653 LOG (GNUNET_ERROR_TYPE_INFO,
654 "Asking gnunet-nat-server to connect to `%s'\n",
658 msg.header.size = htons (sizeof (struct GNUNET_NAT_TestMessage));
659 msg.header.type = htons (GNUNET_MESSAGE_TYPE_NAT_TEST);
660 msg.dst_ipv4 = inet_addr(ah->stun_ip);
661 msg.dport = htons(ah->stun_port);
663 msg.is_tcp = htonl ((uint32_t) GNUNET_NO);
665 client = GNUNET_CLIENT_connect ("gnunet-nat-server", ah->cfg);
668 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
669 _("Failed to connect to `gnunet-nat-server'\n"));
673 GNUNET_break (GNUNET_OK ==
674 GNUNET_CLIENT_transmit_and_get_response (client, &msg.header,
678 ltask4 = GNUNET_SCHEDULER_add_read_net (NAT_SERVER_TIMEOUT,
679 lsock4, &do_udp_read, ah);
684 LOG (GNUNET_ERROR_TYPE_INFO,
685 "We don't have a STUN IP");
696 * Test if UPnPC works.
698 * @param ah auto setup context
701 test_upnpc (struct GNUNET_NAT_AutoHandle *ah)
706 if (GNUNET_NAT_ERROR_SUCCESS != ah->ret)
709 // test if upnpc is available
710 have_upnpc = (GNUNET_SYSERR !=
711 GNUNET_OS_check_helper_binary ("upnpc", GNUNET_NO, NULL));
712 //FIXME: test if upnpc is actually working, that is, if transports start to work once we use UPnP
713 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
715 ? _("upnpc found, enabling its use\n")
716 : _("upnpc not found\n"));
717 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "ENABLE_UPNP",
718 (GNUNET_YES == have_upnpc) ? "YES" : "NO");
725 * Test if ICMP server is working
727 * @param ah auto setup context
730 test_icmp_server (struct GNUNET_NAT_AutoHandle *ah)
743 helper = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-nat-server");
745 GNUNET_CONFIGURATION_get_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
746 &tmp)) && (0 < strlen (tmp))){
748 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("test_icmp_server not possible, as we have no public IPv4 address\n"));
754 GNUNET_CONFIGURATION_get_value_yesno (ah->cfg, "nat", "BEHIND_NAT")){
756 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("test_icmp_server not possible, as we are not behind NAT\n"));
762 GNUNET_OS_check_helper_binary (helper, GNUNET_YES, "-d 127.0.0.1" )){
763 binary = GNUNET_OK; // use localhost as source for that one udp-port, ok for testing
764 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("No working gnunet-helper-nat-server found\n"));
767 GNUNET_free_non_null (tmp);
768 GNUNET_free (helper);
770 if (GNUNET_OK == ext_ip && GNUNET_YES == nated && GNUNET_OK == binary)
771 ah->task = GNUNET_SCHEDULER_add_now (&reversal_test, ah);
779 * Test if ICMP client is working
781 * @param ah auto setup context
784 test_icmp_client (struct GNUNET_NAT_AutoHandle *ah)
792 helper = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-nat-client");
794 GNUNET_CONFIGURATION_get_value_string (ah->cfg, "nat", "INTERNAL_ADDRESS",
795 &tmp)) && (0 < strlen (tmp)))
797 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("test_icmp_client not possible, as we have no internal IPv4 address\n"));
803 GNUNET_CONFIGURATION_get_value_yesno (ah->cfg, "nat", "BEHIND_NAT")){
804 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("test_icmp_server not possible, as we are not behind NAT\n"));
810 GNUNET_OS_check_helper_binary (helper, GNUNET_YES, "-d 127.0.0.1 127.0.0.2 42")){
811 // none of these parameters are actually used in privilege testing mode
812 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("No working gnunet-helper-nat-server found\n"));
815 GNUNET_free_non_null (tmp);
816 GNUNET_free (helper);
824 * Run the next phase of the auto test.
827 next_phase (struct GNUNET_NAT_AutoHandle *ah)
829 struct GNUNET_CONFIGURATION_Handle *diff;
837 case AUTO_EXTERNAL_IP:
838 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_EXTERNAL_IP\n");
839 test_external_ip (ah);
842 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_STUN\n");
846 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_LOCAL_IP\n");
849 case AUTO_NAT_PUNCHED:
850 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run GNUNET_ERROR_TYPE_DEBUG\n");
851 test_nat_punched (ah);
854 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_UPNPC\n");
857 case AUTO_ICMP_SERVER:
858 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_ICMP_SERVER\n");
859 test_icmp_server (ah);
861 case AUTO_ICMP_CLIENT:
862 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_ICMP_CLIENT\n");
863 test_icmp_client (ah);
866 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Done with tests\n");
867 if (!ah->internal_ip_is_public)
869 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "YES");
871 if (ah->connected_back)
873 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "PUNCHED_NAT", "YES");
877 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "PUNCHED_NAT", "NO");
882 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
884 if (ah->connected_back)
886 ah->type = GNUNET_NAT_TYPE_STUN_PUNCHED_NAT;
887 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "USE_STUN", "YES");
891 ah->type = GNUNET_NAT_TYPE_UNREACHABLE_NAT;
892 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "USE_STUN", "NO");
898 GNUNET_CONFIGURATION_set_value_number (ah->cfg, "transport-udp",
906 //The internal IP is the same as public, but we didn't got a incoming connection
907 if (ah->connected_back)
909 ah->type = GNUNET_NAT_TYPE_NO_NAT;
910 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "NO");
914 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "YES");
915 ah->type = GNUNET_NAT_TYPE_UNREACHABLE_NAT;
918 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
923 GNUNET_CONFIGURATION_set_value_number (ah->cfg, "transport-udp",
931 diff = GNUNET_CONFIGURATION_get_diff (ah->initial_cfg,
935 ah->fin_cb (ah->fin_cb_cls,
939 GNUNET_CONFIGURATION_destroy (diff);
940 GNUNET_NAT_autoconfig_cancel (ah);
951 * Start auto-configuration routine. The resolver service should
952 * be available when this function is called.
954 * @param cfg initial configuration
955 * @param cb function to call with autoconfiguration result
956 * @param cb_cls closure for @a cb
957 * @return handle to cancel operation
959 struct GNUNET_NAT_AutoHandle *
960 GNUNET_NAT_autoconfig_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
961 GNUNET_NAT_AutoResultCallback cb,
964 struct GNUNET_NAT_AutoHandle *ah;
966 ah = GNUNET_new (struct GNUNET_NAT_AutoHandle);
968 ah->fin_cb_cls = cb_cls;
969 ah->ret = GNUNET_NAT_ERROR_SUCCESS;
970 ah->cfg = GNUNET_CONFIGURATION_dup (cfg);
971 ah->initial_cfg = GNUNET_CONFIGURATION_dup (cfg);
973 /* never use loopback addresses if user wanted autoconfiguration */
974 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat",
984 * Abort autoconfiguration.
986 * @param ah handle for operation to abort
989 GNUNET_NAT_autoconfig_cancel (struct GNUNET_NAT_AutoHandle *ah)
993 GNUNET_NAT_test_stop (ah->tst);
998 GNUNET_NAT_mini_get_external_ipv4_cancel (ah->eh);
1001 if (NULL != ah->task)
1003 GNUNET_SCHEDULER_cancel (ah->task);
1006 GNUNET_CONFIGURATION_destroy (ah->cfg);
1007 GNUNET_CONFIGURATION_destroy (ah->initial_cfg);
1012 /* end of nat_auto.c */