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3 Copyright (C) 2009-2016 GNUnet e.V.
5 GNUnet is free software; you can redistribute it and/or modify
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
8 option) any later version.
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18 Boston, MA 02110-1301, USA.
22 * @file util/resolver_api.c
23 * @brief resolver for writing a tool
24 * @author Christian Grothoff
27 #include "gnunet_util_lib.h"
28 #include "gnunet_protocols.h"
29 #include "gnunet_resolver_service.h"
32 #define LOG(kind,...) GNUNET_log_from (kind, "util-resolver-api", __VA_ARGS__)
34 #define LOG_STRERROR(kind,syscall) GNUNET_log_from_strerror (kind, "util-resolver-api", syscall)
37 * Maximum supported length for a hostname
39 #define MAX_HOSTNAME 1024
43 * Possible hostnames for "loopback".
45 static const char *loopback[] = {
55 static const struct GNUNET_CONFIGURATION_Handle *resolver_cfg;
58 * Our connection to the resolver service, created on-demand, but then
59 * persists until error or shutdown.
61 static struct GNUNET_MQ_Handle *mq;
64 * Head of DLL of requests.
66 static struct GNUNET_RESOLVER_RequestHandle *req_head;
69 * Tail of DLL of requests.
71 static struct GNUNET_RESOLVER_RequestHandle *req_tail;
74 * How long should we wait to reconnect?
76 static struct GNUNET_TIME_Relative backoff;
79 * Task for reconnecting.
81 static struct GNUNET_SCHEDULER_Task *r_task;
84 * Task ID of shutdown task; only present while we have a
85 * connection to the resolver service.
87 static struct GNUNET_SCHEDULER_Task *s_task;
91 * Handle to a request given to the resolver. Can be used to cancel
92 * the request prior to the timeout or successful execution. Also
93 * used to track our internal state for the request.
95 struct GNUNET_RESOLVER_RequestHandle
99 * Next entry in DLL of requests.
101 struct GNUNET_RESOLVER_RequestHandle *next;
104 * Previous entry in DLL of requests.
106 struct GNUNET_RESOLVER_RequestHandle *prev;
109 * Callback if this is an name resolution request,
112 GNUNET_RESOLVER_AddressCallback addr_callback;
115 * Callback if this is a reverse lookup request,
118 GNUNET_RESOLVER_HostnameCallback name_callback;
121 * Closure for the callbacks.
126 * When should this request time out?
128 struct GNUNET_TIME_Absolute timeout;
131 * Task handle for making reply callbacks in numeric lookups
132 * asynchronous, and for timeout handling.
134 struct GNUNET_SCHEDULER_Task *task;
137 * Desired address family.
142 * Has this request been transmitted to the service?
143 * #GNUNET_YES if transmitted
144 * #GNUNET_YES if not transmitted
145 * #GNUNET_SYSERR when request was canceled
150 * Did we add this request to the queue?
155 * Desired direction (IP to name or name to IP)
160 * #GNUNET_YES if a response was received
162 int received_response;
165 * Length of the data that follows this struct.
172 * Check that the resolver service runs on localhost
175 * @return #GNUNET_OK if the resolver is properly configured,
176 * #GNUNET_SYSERR otherwise.
182 struct sockaddr_in v4;
183 struct sockaddr_in6 v6;
185 memset (&v4, 0, sizeof (v4));
186 v4.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
187 v4.sin_family = AF_INET;
188 #if HAVE_SOCKADDR_IN_SIN_LEN
189 v4.sin_len = sizeof (v4);
191 memset (&v6, 0, sizeof (v6));
192 v6.sin6_family = AF_INET6;
193 #if HAVE_SOCKADDR_IN_SIN_LEN
194 v6.sin6_len = sizeof (v6);
197 GNUNET_CONFIGURATION_get_value_string (resolver_cfg,
202 LOG (GNUNET_ERROR_TYPE_INFO,
203 _("Missing `%s' for `%s' in configuration, DNS resolution will be unavailable.\n"),
206 return GNUNET_SYSERR;
208 if ( (1 == inet_pton (AF_INET, hostname, &v4)) ||
209 (1 == inet_pton (AF_INET6, hostname, &v6)) )
211 GNUNET_free (hostname);
214 for (unsigned int i = 0;
217 if (0 == strcasecmp (loopback[i], hostname))
219 GNUNET_free (hostname);
222 LOG (GNUNET_ERROR_TYPE_INFO,
223 _("Missing `%s' or numeric IP address for `%s' of `%s' in configuration, DNS resolution will be unavailable.\n"),
227 GNUNET_free (hostname);
228 return GNUNET_SYSERR;
233 * Create the connection to the resolver service.
235 * @param cfg configuration to use
238 GNUNET_RESOLVER_connect (const struct GNUNET_CONFIGURATION_Handle *cfg)
240 GNUNET_assert (NULL != cfg);
241 backoff = GNUNET_TIME_UNIT_MILLISECONDS;
247 * Destroy the connection to the resolver service.
250 GNUNET_RESOLVER_disconnect ()
252 struct GNUNET_RESOLVER_RequestHandle *rh;
254 while (NULL != (rh = req_head))
256 GNUNET_assert (GNUNET_SYSERR == rh->was_transmitted);
257 GNUNET_CONTAINER_DLL_remove (req_head,
264 LOG (GNUNET_ERROR_TYPE_DEBUG,
265 "Disconnecting from DNS service\n");
266 GNUNET_MQ_destroy (mq);
271 GNUNET_SCHEDULER_cancel (r_task);
276 GNUNET_SCHEDULER_cancel (s_task);
283 * Task executed on system shutdown.
286 shutdown_task (void *cls)
289 GNUNET_RESOLVER_disconnect ();
290 backoff = GNUNET_TIME_UNIT_MILLISECONDS;
295 * Consider disconnecting if we have no further requests pending.
300 for (struct GNUNET_RESOLVER_RequestHandle *rh = req_head;
303 if (GNUNET_SYSERR != rh->was_transmitted)
307 GNUNET_SCHEDULER_cancel (r_task);
312 s_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MILLISECONDS,
319 * Convert IP address to string without DNS resolution.
321 * @param af address family
322 * @param ip the address
323 * @param ip_len number of bytes in @a ip
324 * @return address as a string, NULL on error
331 char buf[INET6_ADDRSTRLEN];
336 if (ip_len != sizeof (struct in_addr))
344 LOG_STRERROR (GNUNET_ERROR_TYPE_WARNING,
350 if (ip_len != sizeof (struct in6_addr))
358 LOG_STRERROR (GNUNET_ERROR_TYPE_WARNING,
367 return GNUNET_strdup (buf);
372 * Adjust exponential back-off and reconnect to the service.
379 * Generic error handler, called with the appropriate error code and
380 * the same closure specified at the creation of the message queue.
381 * Not every message queue implementation supports an error handler.
384 * @param error error code
387 mq_error_handler (void *cls,
388 enum GNUNET_MQ_Error error)
390 GNUNET_MQ_destroy (mq);
392 LOG (GNUNET_ERROR_TYPE_DEBUG,
393 "MQ error, reconnecting\n");
399 * Process pending requests to the resolver.
404 struct GNUNET_RESOLVER_GetMessage *msg;
405 struct GNUNET_MQ_Envelope *env;
406 struct GNUNET_RESOLVER_RequestHandle *rh = req_head;
415 /* nothing to do, release socket really soon if there is nothing
416 * else happening... */
419 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MILLISECONDS,
424 if (GNUNET_NO != rh->was_transmitted)
425 return; /* waiting for reply */
426 env = GNUNET_MQ_msg_extra (msg,
428 GNUNET_MESSAGE_TYPE_RESOLVER_REQUEST);
429 msg->direction = htonl (rh->direction);
430 msg->af = htonl (rh->af);
431 GNUNET_memcpy (&msg[1],
434 LOG (GNUNET_ERROR_TYPE_DEBUG,
435 "Transmitting DNS resolution request to DNS service\n");
438 rh->was_transmitted = GNUNET_YES;
443 * Check validity of response with a hostname for a DNS lookup.
446 * @param msg message with the hostname
449 check_response (void *cls,
450 const struct GNUNET_MessageHeader *msg)
452 /* implemented in #handle_response() for now */
458 * Check validity of response with a hostname for a DNS lookup.
459 * NOTE: right now rather messy, might want to use different
460 * message types for different response formats in the future.
463 * @param msg message with the response
466 handle_response (void *cls,
467 const struct GNUNET_MessageHeader *msg)
469 struct GNUNET_RESOLVER_RequestHandle *rh = req_head;
473 GNUNET_assert (NULL != rh);
474 size = ntohs (msg->size);
475 if (size == sizeof (struct GNUNET_MessageHeader))
477 LOG (GNUNET_ERROR_TYPE_DEBUG,
478 "Received empty response from DNS service\n");
479 /* message contains not data, just header; end of replies */
480 /* check if request was canceled */
481 if (GNUNET_SYSERR != rh->was_transmitted)
483 /* no reverse lookup was successful, return IP as string */
484 if (NULL != rh->name_callback)
486 if (GNUNET_NO == rh->received_response)
488 nret = no_resolve (rh->af,
491 rh->name_callback (rh->cls, nret);
494 /* finally, make termination call */
495 rh->name_callback (rh->cls,
498 if (NULL != rh->addr_callback)
499 rh->addr_callback (rh->cls,
503 rh->was_transmitted = GNUNET_NO;
504 GNUNET_RESOLVER_request_cancel (rh);
508 /* return reverse lookup results to caller */
509 if (NULL != rh->name_callback)
511 const char *hostname;
513 hostname = (const char *) &msg[1];
514 if (hostname[size - sizeof (struct GNUNET_MessageHeader) - 1] != '\0')
517 if (GNUNET_SYSERR != rh->was_transmitted)
518 rh->name_callback (rh->cls,
520 rh->was_transmitted = GNUNET_NO;
521 GNUNET_RESOLVER_request_cancel (rh);
522 GNUNET_MQ_destroy (mq);
527 LOG (GNUNET_ERROR_TYPE_DEBUG,
528 "Resolver returns `%s' for IP `%s'.\n",
530 GNUNET_a2s ((const void *) &rh[1],
532 if (rh->was_transmitted != GNUNET_SYSERR)
533 rh->name_callback (rh->cls,
535 rh->received_response = GNUNET_YES;
537 /* return lookup results to caller */
538 if (NULL != rh->addr_callback)
540 struct sockaddr_in v4;
541 struct sockaddr_in6 v6;
542 const struct sockaddr *sa;
548 ip_len = size - sizeof (struct GNUNET_MessageHeader);
549 if (ip_len == sizeof (struct in_addr))
551 memset (&v4, 0, sizeof (v4));
552 v4.sin_family = AF_INET;
553 v4.sin_addr = *(struct in_addr*) ip;
554 #if HAVE_SOCKADDR_IN_SIN_LEN
555 v4.sin_len = sizeof (v4);
558 sa = (const struct sockaddr *) &v4;
560 else if (ip_len == sizeof (struct in6_addr))
562 memset (&v6, 0, sizeof (v6));
563 v6.sin6_family = AF_INET6;
564 v6.sin6_addr = *(struct in6_addr*) ip;
565 #if HAVE_SOCKADDR_IN_SIN_LEN
566 v6.sin6_len = sizeof (v6);
569 sa = (const struct sockaddr *) &v6;
574 if (GNUNET_SYSERR != rh->was_transmitted)
575 rh->addr_callback (rh->cls,
578 rh->was_transmitted = GNUNET_NO;
579 GNUNET_RESOLVER_request_cancel (rh);
580 GNUNET_MQ_destroy (mq);
585 LOG (GNUNET_ERROR_TYPE_DEBUG,
586 "Received IP from DNS service\n");
587 if (GNUNET_SYSERR != rh->was_transmitted)
588 rh->addr_callback (rh->cls,
596 * We've been asked to lookup the address for a hostname and were
597 * given a valid numeric string. Perform the callbacks for the
600 * @param cls `struct GNUNET_RESOLVER_RequestHandle` for the request
603 numeric_resolution (void *cls)
605 struct GNUNET_RESOLVER_RequestHandle *rh = cls;
606 struct sockaddr_in v4;
607 struct sockaddr_in6 v6;
608 const char *hostname;
611 memset (&v4, 0, sizeof (v4));
612 v4.sin_family = AF_INET;
613 #if HAVE_SOCKADDR_IN_SIN_LEN
614 v4.sin_len = sizeof (v4);
616 memset (&v6, 0, sizeof (v6));
617 v6.sin6_family = AF_INET6;
618 #if HAVE_SOCKADDR_IN_SIN_LEN
619 v6.sin6_len = sizeof (v6);
621 hostname = (const char *) &rh[1];
622 if ( ( (rh->af == AF_UNSPEC) ||
623 (rh->af == AF_INET) ) &&
624 (1 == inet_pton (AF_INET,
628 rh->addr_callback (rh->cls,
629 (const struct sockaddr *) &v4,
631 if ( (rh->af == AF_UNSPEC) &&
632 (1 == inet_pton (AF_INET6,
636 /* this can happen on some systems IF "hostname" is "localhost" */
637 rh->addr_callback (rh->cls,
638 (const struct sockaddr *) &v6,
641 rh->addr_callback (rh->cls,
647 if ( ( (rh->af == AF_UNSPEC) ||
648 (rh->af == AF_INET6) ) &&
649 (1 == inet_pton (AF_INET6,
653 rh->addr_callback (rh->cls,
654 (const struct sockaddr *) &v6,
656 rh->addr_callback (rh->cls,
662 /* why are we here? this task should not have been scheduled! */
669 * We've been asked to lookup the address for a hostname and were
670 * given a variant of "loopback". Perform the callbacks for the
671 * respective loopback numeric addresses.
673 * @param cls `struct GNUNET_RESOLVER_RequestHandle` for the request
676 loopback_resolution (void *cls)
678 struct GNUNET_RESOLVER_RequestHandle *rh = cls;
679 struct sockaddr_in v4;
680 struct sockaddr_in6 v6;
683 memset (&v4, 0, sizeof (v4));
684 v4.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
685 v4.sin_family = AF_INET;
686 #if HAVE_SOCKADDR_IN_SIN_LEN
687 v4.sin_len = sizeof (v4);
689 memset (&v6, 0, sizeof (v6));
690 v6.sin6_family = AF_INET6;
691 #if HAVE_SOCKADDR_IN_SIN_LEN
692 v6.sin6_len = sizeof (v6);
694 v6.sin6_addr = in6addr_loopback;
698 rh->addr_callback (rh->cls,
699 (const struct sockaddr *) &v4,
703 rh->addr_callback (rh->cls,
704 (const struct sockaddr *) &v6,
708 rh->addr_callback (rh->cls,
709 (const struct sockaddr *) &v6,
711 rh->addr_callback (rh->cls,
712 (const struct sockaddr *) &v4,
720 rh->addr_callback (rh->cls,
723 LOG (GNUNET_ERROR_TYPE_DEBUG,
724 "Finished resolving hostname `%s'.\n",
725 (const char *) &rh[1]);
731 * Now try to reconnect to the resolver service.
736 reconnect_task (void *cls)
738 struct GNUNET_MQ_MessageHandler handlers[] = {
739 GNUNET_MQ_hd_var_size (response,
740 GNUNET_MESSAGE_TYPE_RESOLVER_RESPONSE,
741 struct GNUNET_MessageHeader,
743 GNUNET_MQ_handler_end ()
747 if (NULL == req_head)
748 return; /* no work pending */
749 LOG (GNUNET_ERROR_TYPE_DEBUG,
750 "Trying to connect to DNS service\n");
751 mq = GNUNET_CLIENT_connect (resolver_cfg,
758 LOG (GNUNET_ERROR_TYPE_DEBUG,
759 "Failed to connect, will try again later\n");
768 * Adjust exponential back-off and reconnect to the service.
773 struct GNUNET_RESOLVER_RequestHandle *rh;
777 GNUNET_assert (NULL == mq);
778 if (NULL != (rh = req_head))
780 switch (rh->was_transmitted)
783 /* nothing more to do */
786 /* disconnected, transmit again! */
787 rh->was_transmitted = GNUNET_NO;
790 /* request was cancelled, remove entirely */
791 GNUNET_CONTAINER_DLL_remove (req_head,
802 LOG (GNUNET_ERROR_TYPE_DEBUG,
803 "Will try to connect to DNS service in %s\n",
804 GNUNET_STRINGS_relative_time_to_string (backoff,
806 GNUNET_assert (NULL != resolver_cfg);
807 r_task = GNUNET_SCHEDULER_add_delayed (backoff,
810 backoff = GNUNET_TIME_STD_BACKOFF (backoff);
815 * A DNS resolution timed out. Notify the application.
817 * @param cls the `struct GNUNET_RESOLVER_RequestHandle *`
820 handle_lookup_timeout (void *cls)
822 struct GNUNET_RESOLVER_RequestHandle *rh = cls;
825 if (GNUNET_NO == rh->direction)
827 LOG (GNUNET_ERROR_TYPE_INFO,
828 _("Timeout trying to resolve hostname `%s'.\n"),
829 (const char *) &rh[1]);
830 if (NULL != rh->addr_callback)
831 rh->addr_callback (rh->cls,
837 #if !defined(GNUNET_CULL_LOGGING)
838 char buf[INET6_ADDRSTRLEN];
840 LOG (GNUNET_ERROR_TYPE_INFO,
841 _("Timeout trying to resolve IP address `%s'.\n"),
843 (const void *) &rh[1],
847 if (GNUNET_NO == rh->received_response)
851 nret = no_resolve (rh->af,
854 if (NULL != rh->name_callback)
855 rh->name_callback (rh->cls, nret);
858 /* finally, make termination call */
859 if (NULL != rh->name_callback)
860 rh->name_callback (rh->cls,
863 rh->was_transmitted = GNUNET_NO;
864 GNUNET_RESOLVER_request_cancel (rh);
870 * Convert a string to one or more IP addresses.
872 * @param hostname the hostname to resolve
873 * @param af AF_INET or AF_INET6; use AF_UNSPEC for "any"
874 * @param callback function to call with addresses
875 * @param callback_cls closure for @a callback
876 * @param timeout how long to try resolving
877 * @return handle that can be used to cancel the request, NULL on error
879 struct GNUNET_RESOLVER_RequestHandle *
880 GNUNET_RESOLVER_ip_get (const char *hostname,
882 struct GNUNET_TIME_Relative timeout,
883 GNUNET_RESOLVER_AddressCallback callback,
886 struct GNUNET_RESOLVER_RequestHandle *rh;
891 slen = strlen (hostname) + 1;
892 if (slen + sizeof (struct GNUNET_RESOLVER_GetMessage) >=
893 GNUNET_MAX_MESSAGE_SIZE)
898 LOG (GNUNET_ERROR_TYPE_DEBUG,
899 "Trying to resolve hostname `%s'.\n",
901 rh = GNUNET_malloc (sizeof (struct GNUNET_RESOLVER_RequestHandle) + slen);
903 rh->addr_callback = callback;
904 rh->cls = callback_cls;
905 GNUNET_memcpy (&rh[1],
909 rh->timeout = GNUNET_TIME_relative_to_absolute (timeout);
910 rh->direction = GNUNET_NO;
911 /* first, check if this is a numeric address */
912 if ( ( (1 == inet_pton (AF_INET,
916 (af == AF_UNSPEC) ) ) ||
917 ( (1 == inet_pton (AF_INET6,
920 ( (af == AF_INET6) ||
921 (af == AF_UNSPEC)) ) )
923 rh->task = GNUNET_SCHEDULER_add_now (&numeric_resolution,
927 /* then, check if this is a loopback address */
928 for (unsigned int i = 0;
931 if (0 == strcasecmp (loopback[i],
934 rh->task = GNUNET_SCHEDULER_add_now (&loopback_resolution,
938 if (GNUNET_OK != check_config ())
943 rh->task = GNUNET_SCHEDULER_add_delayed (timeout,
944 &handle_lookup_timeout,
946 GNUNET_CONTAINER_DLL_insert_tail (req_head,
949 rh->was_queued = GNUNET_YES;
952 GNUNET_SCHEDULER_cancel (s_task);
961 * We've been asked to convert an address to a string without
962 * a reverse lookup, either because the client asked for it
963 * or because the DNS lookup hit a timeout. Do the numeric
964 * conversion and invoke the callback.
966 * @param cls `struct GNUNET_RESOLVER_RequestHandle` for the request
969 numeric_reverse (void *cls)
971 struct GNUNET_RESOLVER_RequestHandle *rh = cls;
975 result = no_resolve (rh->af,
978 LOG (GNUNET_ERROR_TYPE_DEBUG,
979 "Resolver returns `%s'.\n",
983 rh->name_callback (rh->cls,
985 GNUNET_free (result);
987 rh->name_callback (rh->cls,
989 if (NULL != rh->task)
991 GNUNET_SCHEDULER_cancel (rh->task);
999 * Get an IP address as a string.
1001 * @param sa host address
1002 * @param salen length of host address in @a sa
1003 * @param do_resolve use #GNUNET_NO to return numeric hostname
1004 * @param timeout how long to try resolving
1005 * @param callback function to call with hostnames
1006 * last callback is NULL when finished
1007 * @param cls closure for @a callback
1008 * @return handle that can be used to cancel the request
1010 struct GNUNET_RESOLVER_RequestHandle *
1011 GNUNET_RESOLVER_hostname_get (const struct sockaddr *sa,
1014 struct GNUNET_TIME_Relative timeout,
1015 GNUNET_RESOLVER_HostnameCallback callback,
1018 struct GNUNET_RESOLVER_RequestHandle *rh;
1022 if (GNUNET_OK != check_config ())
1024 LOG (GNUNET_ERROR_TYPE_ERROR,
1025 _("Resolver not configured correctly.\n"));
1029 switch (sa->sa_family)
1032 GNUNET_assert (salen == sizeof (struct sockaddr_in));
1033 ip_len = sizeof (struct in_addr);
1034 ip = &((const struct sockaddr_in*)sa)->sin_addr;
1037 GNUNET_assert (salen == sizeof (struct sockaddr_in6));
1038 ip_len = sizeof (struct in6_addr);
1039 ip = &((const struct sockaddr_in6*)sa)->sin6_addr;
1045 rh = GNUNET_malloc (sizeof (struct GNUNET_RESOLVER_RequestHandle) + salen);
1046 rh->name_callback = callback;
1048 rh->af = sa->sa_family;
1049 rh->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1050 GNUNET_memcpy (&rh[1],
1053 rh->data_len = ip_len;
1054 rh->direction = GNUNET_YES;
1055 rh->received_response = GNUNET_NO;
1056 if (GNUNET_NO == do_resolve)
1058 rh->task = GNUNET_SCHEDULER_add_now (&numeric_reverse,
1062 rh->task = GNUNET_SCHEDULER_add_delayed (timeout,
1063 &handle_lookup_timeout,
1065 GNUNET_CONTAINER_DLL_insert_tail (req_head,
1068 rh->was_queued = GNUNET_YES;
1071 GNUNET_SCHEDULER_cancel (s_task);
1074 process_requests ();
1080 * Get local fully qualified af name
1085 GNUNET_RESOLVER_local_fqdn_get ()
1087 char hostname[GNUNET_OS_get_hostname_max_length () + 1];
1089 if (0 != gethostname (hostname,
1090 sizeof (hostname) - 1))
1092 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
1096 LOG (GNUNET_ERROR_TYPE_DEBUG,
1097 "Resolving our FQDN `%s'\n",
1099 #if HAVE_GETADDRINFO
1101 struct addrinfo *ai;
1105 if (0 != (ret = getaddrinfo (hostname,
1110 LOG (GNUNET_ERROR_TYPE_ERROR,
1111 _("Could not resolve our FQDN: %s\n"),
1112 gai_strerror (ret));
1115 if (NULL != ai->ai_canonname)
1116 rval = GNUNET_strdup (ai->ai_canonname);
1118 rval = GNUNET_strdup (hostname);
1122 #elif HAVE_GETHOSTBYNAME2
1124 struct hostent *host;
1126 host = gethostbyname2 (hostname,
1129 host = gethostbyname2 (hostname,
1133 LOG (GNUNET_ERROR_TYPE_ERROR,
1134 _("Could not resolve our FQDN: %s\n"),
1135 hstrerror (h_errno));
1138 return GNUNET_strdup (host->h_name);
1140 #elif HAVE_GETHOSTBYNAME
1142 struct hostent *host;
1144 host = gethostbyname (hostname);
1147 LOG (GNUNET_ERROR_TYPE_ERROR,
1148 _("Could not resolve our FQDN: %s\n"),
1149 hstrerror (h_errno));
1152 return GNUNET_strdup (host->h_name);
1155 /* fallback: just hope name is already FQDN */
1156 return GNUNET_strdup (hostname);
1162 * Looking our own hostname.
1164 * @param af AF_INET or AF_INET6; use AF_UNSPEC for "any"
1165 * @param timeout how long to try resolving
1166 * @param callback function to call with addresses
1167 * @param cls closure for @a callback
1168 * @return handle that can be used to cancel the request, NULL on error
1170 struct GNUNET_RESOLVER_RequestHandle *
1171 GNUNET_RESOLVER_hostname_resolve (int af,
1172 struct GNUNET_TIME_Relative timeout,
1173 GNUNET_RESOLVER_AddressCallback callback,
1176 char hostname[GNUNET_OS_get_hostname_max_length () + 1];
1178 if (0 != gethostname (hostname, sizeof (hostname) - 1))
1180 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
1184 LOG (GNUNET_ERROR_TYPE_DEBUG,
1185 "Resolving our hostname `%s'\n",
1187 return GNUNET_RESOLVER_ip_get (hostname,
1196 * Cancel a request that is still pending with the resolver.
1197 * Note that a client MUST NOT cancel a request that has
1198 * been completed (i.e, the callback has been called to
1199 * signal timeout or the final result).
1201 * @param rh handle of request to cancel
1204 GNUNET_RESOLVER_request_cancel (struct GNUNET_RESOLVER_RequestHandle *rh)
1206 if (GNUNET_NO == rh->direction)
1207 LOG (GNUNET_ERROR_TYPE_DEBUG,
1208 "Asked to cancel request to resolve hostname `%s'.\n",
1209 (const char *) &rh[1]);
1210 if (NULL != rh->task)
1212 GNUNET_SCHEDULER_cancel (rh->task);
1215 if (GNUNET_NO == rh->was_transmitted)
1217 if (GNUNET_YES == rh->was_queued)
1218 GNUNET_CONTAINER_DLL_remove (req_head,
1222 check_disconnect ();
1225 GNUNET_assert (GNUNET_YES == rh->was_transmitted);
1226 rh->was_transmitted = GNUNET_SYSERR; /* mark as cancelled */
1227 check_disconnect ();
1231 /* end of resolver_api.c */