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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 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.
261 * @param tc scheduler context
264 do_udp_read (void *cls,
265 const struct GNUNET_SCHEDULER_TaskContext *tc)
267 struct GNUNET_NAT_AutoHandle *ah = cls;
268 unsigned char reply_buf[1024];
270 struct sockaddr_in answer;
273 if ((0 != (tc->reason & GNUNET_SCHEDULER_REASON_READ_READY)) &&
274 (GNUNET_NETWORK_fdset_isset (tc->read_ready,
277 rlen = GNUNET_NETWORK_socket_recv (lsock4, reply_buf, sizeof (reply_buf));
279 //Lets handle the packet
280 memset(&answer, 0, sizeof(struct sockaddr_in));
281 if(ah->phase == AUTO_NAT_PUNCHED)
283 //Destroy the connection
284 GNUNET_NETWORK_socket_close (lsock4);
285 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
286 "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);
305 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
306 "TIMEOUT while waiting for an answer\n");
307 if (ah->phase == AUTO_NAT_PUNCHED)
321 * Create an IPv4 listen socket bound to our port.
323 * @return NULL on error
325 static struct GNUNET_NETWORK_Handle *
328 struct GNUNET_NETWORK_Handle *ls;
329 struct sockaddr_in sa4;
332 memset (&sa4, 0, sizeof (sa4));
333 sa4.sin_family = AF_INET;
334 sa4.sin_port = htons (port);
335 #if HAVE_SOCKADDR_IN_SIN_LEN
336 sa4.sin_len = sizeof (sa4);
338 ls = GNUNET_NETWORK_socket_create (AF_INET,
344 GNUNET_NETWORK_socket_bind (ls, (const struct sockaddr *) &sa4,
348 GNUNET_NETWORK_socket_close (ls);
358 static void request_callback (void *cls,
359 enum GNUNET_NAT_StatusCode result)
361 // struct GNUNET_NAT_AutoHandle *ah = cls;
363 GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Request callback: stop and quit\n");
366 // next_phase (ah); FIXME this always will be NULL, as called in test_stun()
374 * Function called by NAT to report the outcome of the nat-test.
375 * Clean up and update GUI.
377 * @param cls the auto handle
378 * @param success currently always #GNUNET_OK
379 * @param emsg NULL on success, otherwise an error message
382 result_callback (void *cls,
383 enum GNUNET_NAT_StatusCode ret)
385 struct GNUNET_NAT_AutoHandle *ah = cls;
387 if (GNUNET_NAT_ERROR_SUCCESS == ret)
388 GNUNET_NAT_test_stop (ah->tst);
391 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
392 GNUNET_NAT_ERROR_SUCCESS == ret
393 ? _("NAT traversal with ICMP Server succeeded.\n")
394 : _("NAT traversal with ICMP Server failed.\n"));
395 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "ENABLE_ICMP_SERVER",
396 GNUNET_NAT_ERROR_SUCCESS == ret ? "NO" : "YES");
402 * Main function for the connection reversal test.
404 * @param cls the `struct GNUNET_NAT_AutoHandle`
405 * @param tc scheduler context
408 reversal_test (void *cls,
409 const struct GNUNET_SCHEDULER_TaskContext *tc)
411 struct GNUNET_NAT_AutoHandle *ah = cls;
414 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
415 _("Testing connection reversal with ICMP server.\n"));
416 GNUNET_RESOLVER_connect (ah->cfg);
417 ah->tst = GNUNET_NAT_test_start (ah->cfg, GNUNET_YES, 0, 0, TIMEOUT,
418 &result_callback, ah);
423 * Set our external IPv4 address based on the UPnP.
426 * @param cls closure with our setup context
427 * @param addr the address, NULL on errors
428 * @param emsg NULL on success, otherwise an error message
431 set_external_ipv4 (void *cls,
432 const struct in_addr *addr,
433 enum GNUNET_NAT_StatusCode ret)
435 struct GNUNET_NAT_AutoHandle *ah = cls;
436 char buf[INET_ADDRSTRLEN];
440 if (GNUNET_NAT_ERROR_SUCCESS != ret)
445 /* enable 'behind nat' */
446 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
447 _("Detected external IP `%s'\n"),
452 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "YES");
454 /* set external IP address */
455 if (NULL == inet_ntop (AF_INET, addr, buf, sizeof (buf)))
458 /* actually, this should never happen, as the caller already executed just
459 * this check, but for consistency (eg: future changes in the caller)
460 * we still need to report this error...
462 ah->ret = GNUNET_NAT_ERROR_EXTERNAL_IP_ADDRESS_INVALID;
466 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
468 ah->upnp_set_external_address = GNUNET_YES;
474 * Determine our external IPv4 address.
476 * @param ah auto setup context
479 test_external_ip (struct GNUNET_NAT_AutoHandle *ah)
481 if (GNUNET_NAT_ERROR_SUCCESS != ah->ret)
485 /* try to detect external IP */
486 ah->eh = GNUNET_NAT_mini_get_external_ipv4 (TIMEOUT,
487 &set_external_ipv4, ah);
492 * Determine our external IPv4 address and port using an external STUN server
494 * @param ah auto setup context
497 test_stun (struct GNUNET_NAT_AutoHandle *ah)
500 GNUNET_log (GNUNET_ERROR_TYPE_INFO, "Running STUN test\n");
502 /* Get port from the configuration */
504 GNUNET_CONFIGURATION_get_value_number (ah->cfg,
512 //Lets create the socket
516 GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "bind");
522 //Lets call our function now when it accepts
523 ltask4 = GNUNET_SCHEDULER_add_read_net (NAT_SERVER_TIMEOUT,
524 lsock4, &do_udp_read, ah);
529 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
530 "STUN service listens on port %u\n",
532 if (GNUNET_NO == GNUNET_NAT_stun_make_request (stun_server, stun_port,
533 lsock4, &request_callback,
536 /*An error happened*/
537 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "STUN error, stopping\n");
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,
680 GNUNET_SCHEDULER_cancel (ltask4);
681 ltask4 = GNUNET_SCHEDULER_add_read_net (NAT_SERVER_TIMEOUT,
682 lsock4, &do_udp_read, ah);
688 LOG (GNUNET_ERROR_TYPE_INFO,
689 "We don't have a STUN IP");
700 * Test if UPnPC works.
702 * @param ah auto setup context
705 test_upnpc (struct GNUNET_NAT_AutoHandle *ah)
710 if (GNUNET_NAT_ERROR_SUCCESS != ah->ret)
713 // test if upnpc is available
714 have_upnpc = (GNUNET_SYSERR !=
715 GNUNET_OS_check_helper_binary ("upnpc", GNUNET_NO, NULL));
716 //FIXME: test if upnpc is actually working, that is, if transports start to work once we use UPnP
717 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
719 ? _("upnpc found, enabling its use\n")
720 : _("upnpc not found\n"));
721 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "ENABLE_UPNP",
722 (GNUNET_YES == have_upnpc) ? "YES" : "NO");
729 * Test if ICMP server is working
731 * @param ah auto setup context
734 test_icmp_server (struct GNUNET_NAT_AutoHandle *ah)
747 helper = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-nat-server");
749 GNUNET_CONFIGURATION_get_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
750 &tmp)) && (0 < strlen (tmp))){
752 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("test_icmp_server not possible, as we have no public IPv4 address\n"));
758 GNUNET_CONFIGURATION_get_value_yesno (ah->cfg, "nat", "BEHIND_NAT")){
760 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("test_icmp_server not possible, as we are not behind NAT\n"));
766 GNUNET_OS_check_helper_binary (helper, GNUNET_YES, "-d 127.0.0.1" )){
767 binary = GNUNET_OK; // use localhost as source for that one udp-port, ok for testing
768 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("No working gnunet-helper-nat-server found\n"));
771 GNUNET_free_non_null (tmp);
772 GNUNET_free (helper);
774 if (GNUNET_OK == ext_ip && GNUNET_YES == nated && GNUNET_OK == binary)
775 ah->task = GNUNET_SCHEDULER_add_now (&reversal_test, ah);
783 * Test if ICMP client is working
785 * @param ah auto setup context
788 test_icmp_client (struct GNUNET_NAT_AutoHandle *ah)
796 helper = GNUNET_OS_get_libexec_binary_path ("gnunet-helper-nat-client");
798 GNUNET_CONFIGURATION_get_value_string (ah->cfg, "nat", "INTERNAL_ADDRESS",
799 &tmp)) && (0 < strlen (tmp)))
801 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("test_icmp_client not possible, as we have no internal IPv4 address\n"));
807 GNUNET_CONFIGURATION_get_value_yesno (ah->cfg, "nat", "BEHIND_NAT")){
808 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("test_icmp_server not possible, as we are not behind NAT\n"));
814 GNUNET_OS_check_helper_binary (helper, GNUNET_YES, "-d 127.0.0.1 127.0.0.2 42")){
815 // none of these parameters are actually used in privilege testing mode
816 GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("No working gnunet-helper-nat-server found\n"));
819 GNUNET_free_non_null (tmp);
820 GNUNET_free (helper);
828 * Run the next phase of the auto test.
831 next_phase (struct GNUNET_NAT_AutoHandle *ah)
833 struct GNUNET_CONFIGURATION_Handle *diff;
841 case AUTO_EXTERNAL_IP:
842 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_EXTERNAL_IP\n");
843 test_external_ip (ah);
846 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_STUN\n");
850 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_LOCAL_IP\n");
853 case AUTO_NAT_PUNCHED:
854 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_NAT_PUNCHED\n");
855 test_nat_punched (ah);
858 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_UPNPC\n");
861 case AUTO_ICMP_SERVER:
862 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_ICMP_SERVER\n");
863 test_icmp_server (ah);
865 case AUTO_ICMP_CLIENT:
866 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Will run AUTO_ICMP_CLIENT\n");
867 test_icmp_client (ah);
870 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,"Done with tests\n");
871 if (!ah->internal_ip_is_public)
873 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "YES");
875 if (ah->connected_back)
877 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "PUNCHED_NAT", "YES");
881 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "PUNCHED_NAT", "NO");
886 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
888 if (ah->connected_back)
890 ah->type = GNUNET_NAT_TYPE_STUN_PUNCHED_NAT;
891 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "USE_STUN", "YES");
895 ah->type = GNUNET_NAT_TYPE_UNREACHABLE_NAT;
896 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "USE_STUN", "NO");
902 GNUNET_CONFIGURATION_set_value_number (ah->cfg, "transport-udp",
910 //The internal IP is the same as public, but we didn't got a incoming connection
911 if (ah->connected_back)
913 ah->type = GNUNET_NAT_TYPE_NO_NAT;
914 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "NO");
918 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "BEHIND_NAT", "YES");
919 ah->type = GNUNET_NAT_TYPE_UNREACHABLE_NAT;
922 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat", "EXTERNAL_ADDRESS",
927 GNUNET_CONFIGURATION_set_value_number (ah->cfg, "transport-udp",
935 diff = GNUNET_CONFIGURATION_get_diff (ah->initial_cfg,
939 ah->fin_cb (ah->fin_cb_cls,
943 GNUNET_CONFIGURATION_destroy (diff);
944 GNUNET_NAT_autoconfig_cancel (ah);
955 * Start auto-configuration routine. The resolver service should
956 * be available when this function is called.
958 * @param cfg initial configuration
959 * @param cb function to call with autoconfiguration result
960 * @param cb_cls closure for @a cb
961 * @return handle to cancel operation
963 struct GNUNET_NAT_AutoHandle *
964 GNUNET_NAT_autoconfig_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
965 GNUNET_NAT_AutoResultCallback cb,
968 struct GNUNET_NAT_AutoHandle *ah;
970 ah = GNUNET_new (struct GNUNET_NAT_AutoHandle);
972 ah->fin_cb_cls = cb_cls;
973 ah->ret = GNUNET_NAT_ERROR_SUCCESS;
974 ah->cfg = GNUNET_CONFIGURATION_dup (cfg);
975 ah->initial_cfg = GNUNET_CONFIGURATION_dup (cfg);
977 /* never use loopback addresses if user wanted autoconfiguration */
978 GNUNET_CONFIGURATION_set_value_string (ah->cfg, "nat",
988 * Abort autoconfiguration.
990 * @param ah handle for operation to abort
993 GNUNET_NAT_autoconfig_cancel (struct GNUNET_NAT_AutoHandle *ah)
997 GNUNET_NAT_test_stop (ah->tst);
1002 GNUNET_NAT_mini_get_external_ipv4_cancel (ah->eh);
1005 if (NULL != ah->task)
1007 GNUNET_SCHEDULER_cancel (ah->task);
1010 GNUNET_CONFIGURATION_destroy (ah->cfg);
1011 GNUNET_CONFIGURATION_destroy (ah->initial_cfg);
1016 /* end of nat_auto.c */