2 This file is part of GNUnet.
3 (C) 2011-2013 Christian Grothoff (and other contributing authors)
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.
10 GNUnet is distributed in the hope that it will be useful, but
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., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
21 * @file gns/gnunet-service-gns.c
22 * @brief GNU Name System (main service)
23 * @author Martin Schanzenbach
24 * @author Christian Grothoff
27 #include "gnunet_util_lib.h"
28 #include "gnunet_dns_service.h"
29 #include "gnunet_dnsparser_lib.h"
30 #include "gnunet_dht_service.h"
31 #include "gnunet_namecache_service.h"
32 #include "gnunet_namestore_service.h"
33 #include "gnunet_gns_service.h"
34 #include "gnunet_statistics_service.h"
36 #include "gnunet-service-gns_resolver.h"
37 #include "gnunet-service-gns_shorten.h"
38 #include "gnunet-service-gns_interceptor.h"
39 #include "gnunet_protocols.h"
42 * The initial interval in milliseconds btween puts in
45 #define INITIAL_PUT_INTERVAL GNUNET_TIME_UNIT_MILLISECONDS
48 * The upper bound for the zone iteration interval in milliseconds
50 #define MINIMUM_ZONE_ITERATION_INTERVAL GNUNET_TIME_UNIT_SECONDS
53 * The default put interval for the zone iteration. In case
56 #define DEFAULT_ZONE_PUBLISH_TIME_WINDOW GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 4)
59 * The factor the current zone iteration interval is divided by for each
60 * additional new record
62 #define LATE_ITERATION_SPEEDUP_FACTOR 2
65 * How long until a DHT PUT attempt should time out?
67 #define DHT_OPERATION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 60)
70 * What replication level do we use for DHT PUT operations?
72 #define DHT_GNS_REPLICATION_LEVEL 5
76 * Handle to a lookup operation from api
78 struct ClientLookupHandle
82 * We keep these in a DLL.
84 struct ClientLookupHandle *next;
87 * We keep these in a DLL.
89 struct ClientLookupHandle *prev;
92 * Handle to the requesting client
94 struct GNUNET_SERVER_Client *client;
97 * Active handle for the lookup.
99 struct GNS_ResolverHandle *lookup;
110 * Our handle to the DHT
112 static struct GNUNET_DHT_Handle *dht_handle;
115 * Active DHT put operation (or NULL)
117 static struct GNUNET_DHT_PutHandle *active_put;
120 * Our handle to the namestore service
122 static struct GNUNET_NAMESTORE_Handle *namestore_handle;
125 * Our handle to the namecache service
127 static struct GNUNET_NAMECACHE_Handle *namecache_handle;
130 * Handle to iterate over our authoritative zone in namestore
132 static struct GNUNET_NAMESTORE_ZoneIterator *namestore_iter;
135 * Our notification context.
137 static struct GNUNET_SERVER_NotificationContext *nc;
142 static struct ClientLookupHandle *clh_head;
147 static struct ClientLookupHandle *clh_tail;
150 * Useful for zone update for DHT put
152 static unsigned long long num_public_records;
155 * Last seen record count
157 static unsigned long long last_num_public_records;
160 * Zone iteration PUT interval.
162 static struct GNUNET_TIME_Relative put_interval;
165 * Time window for zone iteration
167 static struct GNUNET_TIME_Relative zone_publish_time_window;
172 static GNUNET_SCHEDULER_TaskIdentifier zone_publish_task;
175 * #GNUNET_YES if zone has never been published before
177 static int first_zone_iteration;
180 * #GNUNET_YES if ipv6 is supported
182 static int v6_enabled;
185 * #GNUNET_YES if ipv4 is supported
187 static int v4_enabled;
190 * Handle to the statistics service
192 static struct GNUNET_STATISTICS_Handle *statistics;
196 * Task run during shutdown.
202 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
204 struct ClientLookupHandle *clh;
206 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
208 GNUNET_SERVER_notification_context_destroy (nc);
209 while (NULL != (clh = clh_head))
211 GNUNET_SERVER_client_set_user_context (clh->client, NULL);
212 GNS_resolver_lookup_cancel (clh->lookup);
213 GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
217 GNS_interceptor_done ();
218 GNS_resolver_done ();
220 if (NULL != statistics)
222 GNUNET_STATISTICS_destroy (statistics, GNUNET_NO);
225 if (GNUNET_SCHEDULER_NO_TASK != zone_publish_task)
227 GNUNET_SCHEDULER_cancel (zone_publish_task);
228 zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
230 if (NULL != namestore_iter)
232 GNUNET_NAMESTORE_zone_iteration_stop (namestore_iter);
233 namestore_iter = NULL;
235 if (NULL != namestore_handle)
237 GNUNET_NAMESTORE_disconnect (namestore_handle);
238 namestore_handle = NULL;
240 if (NULL != namecache_handle)
242 GNUNET_NAMECACHE_disconnect (namecache_handle);
243 namecache_handle = NULL;
245 if (NULL != active_put)
247 GNUNET_DHT_put_cancel (active_put);
250 if (NULL != dht_handle)
252 GNUNET_DHT_disconnect (dht_handle);
259 * Method called periodically that triggers iteration over authoritative records
262 * @param tc task context
265 publish_zone_dht_next (void *cls,
266 const struct GNUNET_SCHEDULER_TaskContext *tc)
268 zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
269 GNUNET_NAMESTORE_zone_iterator_next (namestore_iter);
274 * Periodically iterate over our zone and store everything in dht
277 * @param tc task context
280 publish_zone_dht_start (void *cls,
281 const struct GNUNET_SCHEDULER_TaskContext *tc);
285 * Continuation called from DHT once the PUT operation is done.
287 * @param cls closure, NULL
288 * @param success #GNUNET_OK on success
291 dht_put_continuation (void *cls,
294 struct GNUNET_TIME_Relative next_put_interval;
297 num_public_records++;
298 if ( (num_public_records > last_num_public_records) &&
299 (GNUNET_NO == first_zone_iteration) )
301 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
302 "Last record count was lower than current record count. Reducing interval.\n");
303 put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
305 next_put_interval = GNUNET_TIME_relative_divide (put_interval,
306 LATE_ITERATION_SPEEDUP_FACTOR);
309 next_put_interval = put_interval;
311 GNUNET_STATISTICS_set (statistics,
312 "Current zone iteration interval (ms)",
313 next_put_interval.rel_value_us / 1000LL,
315 zone_publish_task = GNUNET_SCHEDULER_add_delayed (next_put_interval,
316 &publish_zone_dht_next,
322 * Function used to put all records successively into the DHT.
324 * @param cls the closure (NULL)
325 * @param key the private key of the authority (ours)
326 * @param name the name of the records, NULL once the iteration is done
327 * @param rd_count the number of records in @a rd
328 * @param rd the record data
331 put_gns_record (void *cls,
332 const struct GNUNET_CRYPTO_EcdsaPrivateKey *key,
334 unsigned int rd_count,
335 const struct GNUNET_GNSRECORD_Data *rd)
337 struct GNUNET_GNSRECORD_Block *block;
338 struct GNUNET_HashCode query;
339 struct GNUNET_TIME_Absolute expire;
340 struct GNUNET_TIME_Absolute now;
342 struct GNUNET_GNSRECORD_Data rd_public[rd_count];
343 unsigned int rd_public_count;
348 /* we're done with one iteration, calculate when to do the next one */
349 namestore_iter = NULL;
350 last_num_public_records = num_public_records;
351 first_zone_iteration = GNUNET_NO;
352 if (0 == num_public_records)
355 * If no records are known (startup) or none present
356 * we can safely set the interval to the value for a single
359 put_interval = zone_publish_time_window;
360 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
361 "No records in namestore database.\n");
365 put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
368 put_interval = GNUNET_TIME_relative_max (MINIMUM_ZONE_ITERATION_INTERVAL,
371 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
372 "Zone iteration finished. Adjusted zone iteration interval to %s\n",
373 GNUNET_STRINGS_relative_time_to_string (put_interval, GNUNET_YES));
374 GNUNET_STATISTICS_set (statistics,
375 "Current zone iteration interval (in ms)",
376 put_interval.rel_value_us / 1000LL,
378 GNUNET_STATISTICS_update (statistics,
379 "Number of zone iterations",
382 GNUNET_STATISTICS_set (statistics,
383 "Number of public records in DHT",
384 last_num_public_records,
386 if (0 == num_public_records)
387 zone_publish_task = GNUNET_SCHEDULER_add_delayed (put_interval,
388 &publish_zone_dht_start,
391 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
396 /* filter out records that are not public, and convert to
397 absolute expiration time. */
399 now = GNUNET_TIME_absolute_get ();
400 for (i=0;i<rd_count;i++)
401 if (0 == (rd[i].flags & (GNUNET_GNSRECORD_RF_PRIVATE |
402 GNUNET_GNSRECORD_RF_PENDING)))
404 rd_public[rd_public_count] = rd[i];
405 if (0 != (rd[i].flags & GNUNET_GNSRECORD_RF_RELATIVE_EXPIRATION))
407 rd_public[rd_public_count].flags &= ~GNUNET_GNSRECORD_RF_RELATIVE_EXPIRATION;
408 rd_public[rd_public_count].expiration_time += now.abs_value_us;
413 /* We got a set of records to publish */
414 if (0 == rd_public_count)
416 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_next,
420 expire = GNUNET_GNSRECORD_record_get_expiration_time (rd_public_count,
422 block = GNUNET_GNSRECORD_block_create (key,
427 block_size = ntohl (block->purpose.size)
428 + sizeof (struct GNUNET_CRYPTO_EcdsaSignature)
429 + sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey);
430 GNUNET_GNSRECORD_query_from_private_key (key,
433 active_put = GNUNET_DHT_put (dht_handle, &query,
434 DHT_GNS_REPLICATION_LEVEL,
435 GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE,
436 GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
440 DHT_OPERATION_TIMEOUT,
441 &dht_put_continuation,
443 if (NULL == active_put)
446 dht_put_continuation (NULL, GNUNET_NO);
453 * Periodically iterate over our zone and store everything in dht
456 * @param tc task context
459 publish_zone_dht_start (void *cls,
460 const struct GNUNET_SCHEDULER_TaskContext *tc)
462 zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
464 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
465 "Starting DHT zone update!\n");
466 /* start counting again */
467 num_public_records = 0;
468 namestore_iter = GNUNET_NAMESTORE_zone_iteration_start (namestore_handle,
469 NULL, /* All zones */
475 /* END DHT ZONE PROPAGATION */
479 * Reply to client with the result from our lookup.
481 * @param cls the closure (our client lookup handle)
482 * @param rd_count the number of records in @a rd
483 * @param rd the record data
486 send_lookup_response (void* cls,
488 const struct GNUNET_GNSRECORD_Data *rd)
490 struct ClientLookupHandle *clh = cls;
491 struct GNUNET_GNS_ClientLookupResultMessage *rmsg;
494 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
495 "Sending `%s' message with %d results\n",
499 len = GNUNET_GNSRECORD_records_get_size (rd_count, rd);
500 rmsg = GNUNET_malloc (len + sizeof (struct GNUNET_GNS_ClientLookupResultMessage));
501 rmsg->header.type = htons (GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT);
502 rmsg->header.size = htons (len + sizeof(struct GNUNET_GNS_ClientLookupResultMessage));
503 rmsg->id = clh->request_id;
504 rmsg->rd_count = htonl (rd_count);
505 GNUNET_GNSRECORD_records_serialize (rd_count, rd, len,
507 GNUNET_SERVER_notification_context_unicast (nc,
512 GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
513 GNUNET_SERVER_client_set_user_context (clh->client, NULL);
515 GNUNET_STATISTICS_update (statistics,
516 "Completed lookups", 1,
518 GNUNET_STATISTICS_update (statistics,
526 * Handle lookup requests from client
528 * @param cls the closure
529 * @param client the client
530 * @param message the message
533 handle_lookup (void *cls,
534 struct GNUNET_SERVER_Client *client,
535 const struct GNUNET_MessageHeader *message)
537 char name[GNUNET_DNSPARSER_MAX_NAME_LENGTH + 1];
538 struct ClientLookupHandle *clh;
539 char *nameptr = name;
541 const struct GNUNET_CRYPTO_EcdsaPrivateKey *key;
543 const struct GNUNET_GNS_ClientLookupMessage *sh_msg;
545 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
546 "Received `%s' message\n",
548 msg_size = ntohs (message->size);
549 if (msg_size < sizeof (struct GNUNET_GNS_ClientLookupMessage))
552 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
555 sh_msg = (const struct GNUNET_GNS_ClientLookupMessage *) message;
556 GNUNET_SERVER_notification_context_add (nc, client);
557 if (GNUNET_YES == ntohs (sh_msg->have_key))
558 key = &sh_msg->shorten_key;
561 utf_in = (const char *) &sh_msg[1];
562 if ( ('\0' != utf_in[msg_size - sizeof (struct GNUNET_GNS_ClientLookupMessage) - 1]) ||
563 (strlen (utf_in) > GNUNET_DNSPARSER_MAX_NAME_LENGTH) )
566 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
569 GNUNET_STRINGS_utf8_tolower (utf_in, &nameptr);
570 GNUNET_SERVER_receive_done (client, GNUNET_OK);
572 clh = GNUNET_new (struct ClientLookupHandle);
573 GNUNET_SERVER_client_set_user_context (client, clh);
574 GNUNET_CONTAINER_DLL_insert (clh_head, clh_tail, clh);
575 clh->client = client;
576 clh->request_id = sh_msg->id;
577 if ( (GNUNET_DNSPARSER_TYPE_A == ntohl (sh_msg->type)) &&
578 (GNUNET_OK != v4_enabled) )
580 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
581 "LOOKUP: Query for A record but AF_INET not supported!");
582 send_lookup_response (clh, 0, NULL);
585 if ( (GNUNET_DNSPARSER_TYPE_AAAA == ntohl (sh_msg->type)) &&
586 (GNUNET_OK != v6_enabled) )
588 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
589 "LOOKUP: Query for AAAA record but AF_INET6 not supported!");
590 send_lookup_response (clh, 0, NULL);
593 clh->lookup = GNS_resolver_lookup (&sh_msg->zone,
594 ntohl (sh_msg->type),
597 ntohl (sh_msg->only_cached),
598 &send_lookup_response, clh);
599 GNUNET_STATISTICS_update (statistics,
606 * One of our clients disconnected, clean up after it.
609 * @param client the client that disconnected
612 notify_client_disconnect (void *cls,
613 struct GNUNET_SERVER_Client *client)
615 struct ClientLookupHandle *clh;
619 clh = GNUNET_SERVER_client_get_user_context (client, struct ClientLookupHandle);
622 GNS_resolver_lookup_cancel (clh->lookup);
623 GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
629 * Process GNS requests.
632 * @param server the initialized server
633 * @param c configuration to use
636 run (void *cls, struct GNUNET_SERVER_Handle *server,
637 const struct GNUNET_CONFIGURATION_Handle *c)
639 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
640 { &handle_lookup, NULL, GNUNET_MESSAGE_TYPE_GNS_LOOKUP, 0},
643 struct GNUNET_CRYPTO_EcdsaPublicKey dns_root;
644 unsigned long long max_parallel_bg_queries = 0;
647 v6_enabled = GNUNET_NETWORK_test_pf (PF_INET6);
648 v4_enabled = GNUNET_NETWORK_test_pf (PF_INET);
650 namestore_handle = GNUNET_NAMESTORE_connect (c);
651 if (NULL == namestore_handle)
653 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
654 _("Failed to connect to the namestore!\n"));
655 GNUNET_SCHEDULER_shutdown ();
658 namecache_handle = GNUNET_NAMECACHE_connect (c);
659 if (NULL == namecache_handle)
661 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
662 _("Failed to connect to the namecache!\n"));
663 GNUNET_SCHEDULER_shutdown ();
667 put_interval = INITIAL_PUT_INTERVAL;
668 zone_publish_time_window = DEFAULT_ZONE_PUBLISH_TIME_WINDOW;
671 GNUNET_CONFIGURATION_get_value_time (c, "gns",
672 "ZONE_PUBLISH_TIME_WINDOW",
673 &zone_publish_time_window))
675 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
676 "Time window for zone iteration: %s\n",
677 GNUNET_STRINGS_relative_time_to_string (zone_publish_time_window, GNUNET_YES));
680 GNUNET_CONFIGURATION_get_value_number (c, "gns",
681 "MAX_PARALLEL_BACKGROUND_QUERIES",
682 &max_parallel_bg_queries))
684 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
685 "Number of allowed parallel background queries: %llu\n",
686 max_parallel_bg_queries);
689 dht_handle = GNUNET_DHT_connect (c,
690 (unsigned int) max_parallel_bg_queries);
691 if (NULL == dht_handle)
693 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
694 _("Could not connect to DHT!\n"));
695 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
700 GNUNET_CONFIGURATION_get_value_string (c, "gns", "DNS_ROOT",
704 GNUNET_CRYPTO_ecdsa_public_key_from_string (dns_root_name,
705 strlen (dns_root_name),
708 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
710 _("valid public key required"));
711 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
712 GNUNET_free (dns_root_name);
715 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
716 "DNS hijacking with root `%s' enabled. Connecting to DNS service.\n",
718 GNUNET_free (dns_root_name);
720 GNS_interceptor_init (&dns_root, c))
722 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
726 GNS_resolver_init (namestore_handle,
730 max_parallel_bg_queries);
731 GNS_shorten_init (namestore_handle,
734 GNUNET_SERVER_disconnect_notify (server,
735 ¬ify_client_disconnect,
737 /* Schedule periodic put for our records. */
738 first_zone_iteration = GNUNET_YES;
739 GNUNET_SERVER_add_handlers (server, handlers);
740 statistics = GNUNET_STATISTICS_create ("gns", c);
741 nc = GNUNET_SERVER_notification_context_create (server, 1);
742 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
744 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
745 &shutdown_task, NULL);
750 * The main function for the GNS service.
752 * @param argc number of arguments from the command line
753 * @param argv command line arguments
754 * @return 0 ok, 1 on error
757 main (int argc, char *const *argv)
763 GNUNET_SERVICE_run (argc, argv, "gns", GNUNET_SERVICE_OPTION_NONE, &run,
768 /* end of gnunet-service-gns.c */