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_namestore_service.h"
32 #include "gnunet_gns_service.h"
33 #include "gnunet_statistics_service.h"
35 #include "gnunet-service-gns_resolver.h"
36 #include "gnunet-service-gns_shorten.h"
37 #include "gnunet-service-gns_interceptor.h"
38 #include "gnunet_protocols.h"
41 * The initial interval in milliseconds btween puts in
44 #define INITIAL_PUT_INTERVAL GNUNET_TIME_UNIT_MILLISECONDS
47 * The upper bound for the zone iteration interval in milliseconds
49 #define MINIMUM_ZONE_ITERATION_INTERVAL GNUNET_TIME_UNIT_SECONDS
52 * The default put interval for the zone iteration. In case
55 #define DEFAULT_ZONE_PUBLISH_TIME_WINDOW GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 4)
58 * The factor the current zone iteration interval is divided by for each
59 * additional new record
61 #define LATE_ITERATION_SPEEDUP_FACTOR 2
64 * How long until a DHT PUT attempt should time out?
66 #define DHT_OPERATION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 60)
69 * What replication level do we use for DHT PUT operations?
71 #define DHT_GNS_REPLICATION_LEVEL 5
75 * Handle to a lookup operation from api
77 struct ClientLookupHandle
81 * We keep these in a DLL.
83 struct ClientLookupHandle *next;
86 * We keep these in a DLL.
88 struct ClientLookupHandle *prev;
91 * Handle to the requesting client
93 struct GNUNET_SERVER_Client *client;
96 * Active handle for the lookup.
98 struct GNS_ResolverHandle *lookup;
109 * Our handle to the DHT
111 static struct GNUNET_DHT_Handle *dht_handle;
114 * Active DHT put operation (or NULL)
116 static struct GNUNET_DHT_PutHandle *active_put;
119 * Our handle to the namestore service
121 static struct GNUNET_NAMESTORE_Handle *namestore_handle;
124 * Handle to iterate over our authoritative zone in namestore
126 static struct GNUNET_NAMESTORE_ZoneIterator *namestore_iter;
129 * Our notification context.
131 static struct GNUNET_SERVER_NotificationContext *nc;
136 static struct ClientLookupHandle *clh_head;
141 static struct ClientLookupHandle *clh_tail;
144 * Useful for zone update for DHT put
146 static unsigned long long num_public_records;
149 * Last seen record count
151 static unsigned long long last_num_public_records;
154 * Zone iteration PUT interval.
156 static struct GNUNET_TIME_Relative put_interval;
159 * Time window for zone iteration
161 static struct GNUNET_TIME_Relative zone_publish_time_window;
166 static GNUNET_SCHEDULER_TaskIdentifier zone_publish_task;
169 * #GNUNET_YES if zone has never been published before
171 static int first_zone_iteration;
176 static struct GNUNET_TIME_Relative default_lookup_timeout;
179 * #GNUNET_YES if ipv6 is supported
181 static int v6_enabled;
184 * #GNUNET_YES if ipv4 is supported
186 static int v4_enabled;
189 * Handle to the statistics service
191 static struct GNUNET_STATISTICS_Handle *statistics;
195 * Task run during shutdown.
201 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
203 struct ClientLookupHandle *clh;
205 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
207 GNUNET_SERVER_notification_context_destroy (nc);
208 while (NULL != (clh = clh_head))
210 GNS_resolver_lookup_cancel (clh->lookup);
211 GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
215 GNS_interceptor_done ();
216 GNS_resolver_done ();
218 if (NULL != statistics)
220 GNUNET_STATISTICS_destroy (statistics, GNUNET_NO);
223 if (GNUNET_SCHEDULER_NO_TASK != zone_publish_task)
225 GNUNET_SCHEDULER_cancel (zone_publish_task);
226 zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
228 if (NULL != namestore_iter)
230 GNUNET_NAMESTORE_zone_iteration_stop (namestore_iter);
231 namestore_iter = NULL;
233 if (NULL != namestore_handle)
235 GNUNET_NAMESTORE_disconnect (namestore_handle);
236 namestore_handle = NULL;
238 if (NULL != active_put)
240 GNUNET_DHT_put_cancel (active_put);
243 if (NULL != dht_handle)
245 GNUNET_DHT_disconnect (dht_handle);
252 * Method called periodically that triggers iteration over authoritative records
255 * @param tc task context
258 publish_zone_dht_next (void *cls,
259 const struct GNUNET_SCHEDULER_TaskContext *tc)
261 zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
262 GNUNET_NAMESTORE_zone_iterator_next (namestore_iter);
267 * Periodically iterate over our zone and store everything in dht
270 * @param tc task context
273 publish_zone_dht_start (void *cls,
274 const struct GNUNET_SCHEDULER_TaskContext *tc);
278 * Continuation called from DHT once the PUT operation is done.
280 * @param cls closure, NULL
281 * @param success #GNUNET_OK on success
284 dht_put_continuation (void *cls,
287 struct GNUNET_TIME_Relative next_put_interval;
289 num_public_records++;
290 if ( (num_public_records > last_num_public_records) &&
291 (GNUNET_NO == first_zone_iteration) )
293 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
294 "Last record count was lower than current record count. Reducing interval.\n");
295 put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
297 next_put_interval = GNUNET_TIME_relative_divide (put_interval,
298 LATE_ITERATION_SPEEDUP_FACTOR);
301 next_put_interval = put_interval;
303 GNUNET_STATISTICS_set (statistics,
304 "Current zone iteration interval (ms)",
305 next_put_interval.rel_value_us / 1000LL,
307 zone_publish_task = GNUNET_SCHEDULER_add_delayed (next_put_interval,
308 &publish_zone_dht_next,
314 * Function used to put all records successively into the DHT.
316 * @param cls the closure (NULL)
317 * @param key the private key of the authority (ours)
318 * @param name the name of the records, NULL once the iteration is done
319 * @param rd_count the number of records in @a rd
320 * @param rd the record data
323 put_gns_record (void *cls,
324 const struct GNUNET_CRYPTO_EccPrivateKey *key,
326 unsigned int rd_count,
327 const struct GNUNET_NAMESTORE_RecordData *rd)
329 struct GNUNET_NAMESTORE_Block *block;
330 struct GNUNET_HashCode query;
331 struct GNUNET_TIME_Absolute expire;
332 struct GNUNET_TIME_Absolute now;
334 struct GNUNET_NAMESTORE_RecordData rd_public[rd_count];
335 unsigned int rd_public_count;
340 /* we're done with one iteration, calculate when to do the next one */
341 namestore_iter = NULL;
342 last_num_public_records = num_public_records;
343 first_zone_iteration = GNUNET_NO;
344 if (0 == num_public_records)
347 * If no records are known (startup) or none present
348 * we can safely set the interval to the value for a single
351 put_interval = zone_publish_time_window;
352 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
353 "No records in namestore database.\n");
357 put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
360 put_interval = GNUNET_TIME_relative_max (MINIMUM_ZONE_ITERATION_INTERVAL,
363 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
364 "Zone iteration finished. Adjusted zone iteration interval to %s\n",
365 GNUNET_STRINGS_relative_time_to_string (put_interval, GNUNET_YES));
366 GNUNET_STATISTICS_set (statistics,
367 "Current zone iteration interval (in ms)",
368 put_interval.rel_value_us / 1000LL,
370 GNUNET_STATISTICS_update (statistics,
371 "Number of zone iterations",
374 GNUNET_STATISTICS_set (statistics,
375 "Number of public records in DHT",
376 last_num_public_records,
378 if (0 == num_public_records)
379 zone_publish_task = GNUNET_SCHEDULER_add_delayed (put_interval,
380 &publish_zone_dht_start,
383 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
388 /* filter out records that are not public, and convert to
389 absolute expiration time. */
391 now = GNUNET_TIME_absolute_get ();
392 for (i=0;i<rd_count;i++)
393 if (0 == (rd[i].flags & (GNUNET_NAMESTORE_RF_PRIVATE |
394 GNUNET_NAMESTORE_RF_PENDING)))
396 rd_public[rd_public_count] = rd[i];
397 if (0 != (rd[i].flags & GNUNET_NAMESTORE_RF_RELATIVE_EXPIRATION))
399 rd_public[rd_public_count].flags &= ~GNUNET_NAMESTORE_RF_RELATIVE_EXPIRATION;
400 rd_public[rd_public_count].expiration_time += now.abs_value_us;
405 /* We got a set of records to publish */
406 if (0 == rd_public_count)
408 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_next,
412 expire = GNUNET_NAMESTORE_record_get_expiration_time (rd_public_count,
414 block = GNUNET_NAMESTORE_block_create (key,
419 block_size = ntohl (block->purpose.size)
420 + sizeof (struct GNUNET_CRYPTO_EccSignature)
421 + sizeof (struct GNUNET_CRYPTO_EccPublicKey);
422 GNUNET_NAMESTORE_query_from_private_key (key,
426 active_put = GNUNET_DHT_put (dht_handle, &query,
427 DHT_GNS_REPLICATION_LEVEL,
428 GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE,
429 GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
433 DHT_OPERATION_TIMEOUT,
434 &dht_put_continuation,
436 if (NULL == active_put)
439 dht_put_continuation (NULL, GNUNET_NO);
446 * Periodically iterate over our zone and store everything in dht
449 * @param tc task context
452 publish_zone_dht_start (void *cls,
453 const struct GNUNET_SCHEDULER_TaskContext *tc)
455 zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
457 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
458 "Scheduling DHT zone update!\n");
459 /* start counting again */
460 num_public_records = 0;
461 namestore_iter = GNUNET_NAMESTORE_zone_iteration_start (namestore_handle,
462 NULL, /* All zones */
468 /* END DHT ZONE PROPAGATION */
472 * Reply to client with the result from our lookup.
474 * @param cls the closure (our client lookup handle)
475 * @param rd_count the number of records in @a rd
476 * @param rd the record data
479 send_lookup_response (void* cls,
481 const struct GNUNET_NAMESTORE_RecordData *rd)
483 struct ClientLookupHandle *clh = cls;
484 struct GNUNET_GNS_ClientLookupResultMessage *rmsg;
487 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
488 "Sending `%s' message with %d results\n",
492 len = GNUNET_NAMESTORE_records_get_size (rd_count, rd);
493 rmsg = GNUNET_malloc (len + sizeof (struct GNUNET_GNS_ClientLookupResultMessage));
494 rmsg->header.type = htons (GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT);
495 rmsg->header.size = htons (len + sizeof(struct GNUNET_GNS_ClientLookupResultMessage));
496 rmsg->id = clh->request_id;
497 rmsg->rd_count = htonl (rd_count);
498 GNUNET_NAMESTORE_records_serialize (rd_count, rd, len,
500 GNUNET_SERVER_notification_context_unicast (nc,
505 GNUNET_SERVER_receive_done (clh->client,
507 GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
509 GNUNET_STATISTICS_update (statistics,
510 "Completed lookups", 1,
512 GNUNET_STATISTICS_update (statistics,
520 * Handle lookup requests from client
522 * @param cls the closure
523 * @param client the client
524 * @param message the message
527 handle_lookup (void *cls,
528 struct GNUNET_SERVER_Client *client,
529 const struct GNUNET_MessageHeader *message)
531 char name[GNUNET_DNSPARSER_MAX_NAME_LENGTH + 1];
532 struct ClientLookupHandle *clh;
533 char *nameptr = name;
535 const struct GNUNET_CRYPTO_EccPrivateKey *key;
537 const struct GNUNET_GNS_ClientLookupMessage *sh_msg;
539 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
540 "Received `%s' message\n",
542 msg_size = ntohs (message->size);
543 if (msg_size < sizeof (struct GNUNET_GNS_ClientLookupMessage))
546 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
549 sh_msg = (const struct GNUNET_GNS_ClientLookupMessage *) message;
550 GNUNET_SERVER_notification_context_add (nc, client);
551 if (GNUNET_YES == ntohl (sh_msg->have_key))
552 key = &sh_msg->shorten_key;
555 utf_in = (const char *) &sh_msg[1];
556 if ( ('\0' != utf_in[msg_size - sizeof (struct GNUNET_GNS_ClientLookupMessage) - 1]) ||
557 (strlen (utf_in) > GNUNET_DNSPARSER_MAX_NAME_LENGTH) )
560 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
563 GNUNET_STRINGS_utf8_tolower (utf_in, &nameptr);
565 clh = GNUNET_new (struct ClientLookupHandle);
566 GNUNET_SERVER_client_set_user_context (client, clh);
567 GNUNET_CONTAINER_DLL_insert (clh_head, clh_tail, clh);
568 clh->client = client;
569 clh->request_id = sh_msg->id;
570 if ( (GNUNET_DNSPARSER_TYPE_A == ntohl (sh_msg->type)) &&
571 (GNUNET_OK != v4_enabled) )
573 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
574 "LOOKUP: Query for A record but AF_INET not supported!");
575 send_lookup_response (clh, 0, NULL);
578 if ( (GNUNET_DNSPARSER_TYPE_AAAA == ntohl (sh_msg->type)) &&
579 (GNUNET_OK != v6_enabled) )
581 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
582 "LOOKUP: Query for AAAA record but AF_INET6 not supported!");
583 send_lookup_response (clh, 0, NULL);
586 clh->lookup = GNS_resolver_lookup (&sh_msg->zone,
587 ntohl (sh_msg->type),
590 ntohl (sh_msg->only_cached),
591 &send_lookup_response, clh);
592 GNUNET_STATISTICS_update (statistics,
599 * One of our clients disconnected, clean up after it.
602 * @param client the client that disconnected
605 notify_client_disconnect (void *cls,
606 struct GNUNET_SERVER_Client *client)
608 struct ClientLookupHandle *clh;
612 clh = GNUNET_SERVER_client_get_user_context (client, struct ClientLookupHandle);
615 GNS_resolver_lookup_cancel (clh->lookup);
616 GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
622 * Process GNS requests.
625 * @param server the initialized server
626 * @param c configuration to use
629 run (void *cls, struct GNUNET_SERVER_Handle *server,
630 const struct GNUNET_CONFIGURATION_Handle *c)
632 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
633 { &handle_lookup, NULL, GNUNET_MESSAGE_TYPE_GNS_LOOKUP, 0},
636 struct GNUNET_CRYPTO_EccPublicKey dns_root;
637 unsigned long long max_parallel_bg_queries = 0;
640 v6_enabled = GNUNET_NETWORK_test_pf (PF_INET6);
641 v4_enabled = GNUNET_NETWORK_test_pf (PF_INET);
643 namestore_handle = GNUNET_NAMESTORE_connect (c);
644 if (NULL == namestore_handle)
646 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
647 _("Failed to connect to the namestore!\n"));
648 GNUNET_SCHEDULER_shutdown ();
652 put_interval = INITIAL_PUT_INTERVAL;
653 zone_publish_time_window = DEFAULT_ZONE_PUBLISH_TIME_WINDOW;
656 GNUNET_CONFIGURATION_get_value_time (c, "gns",
657 "ZONE_PUBLISH_TIME_WINDOW",
658 &zone_publish_time_window))
660 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
661 "Time window for zone iteration: %s\n",
662 GNUNET_STRINGS_relative_time_to_string (zone_publish_time_window, GNUNET_YES));
665 GNUNET_CONFIGURATION_get_value_number (c, "gns",
666 "MAX_PARALLEL_BACKGROUND_QUERIES",
667 &max_parallel_bg_queries))
669 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
670 "Number of allowed parallel background queries: %llu\n",
671 max_parallel_bg_queries);
675 GNUNET_CONFIGURATION_get_value_time (c, "gns",
676 "DEFAULT_LOOKUP_TIMEOUT",
677 &default_lookup_timeout))
679 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
680 "Default lookup timeout: %s\n",
681 GNUNET_STRINGS_relative_time_to_string (default_lookup_timeout,
685 dht_handle = GNUNET_DHT_connect (c,
686 (unsigned int) max_parallel_bg_queries);
687 if (NULL == dht_handle)
689 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
690 _("Could not connect to DHT!\n"));
691 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
696 GNUNET_CONFIGURATION_get_value_string (c, "gns", "DNS_ROOT",
700 GNUNET_CRYPTO_ecc_public_key_from_string (dns_root_name,
701 strlen (dns_root_name),
704 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
706 _("valid public key required"));
707 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
708 GNUNET_free (dns_root_name);
711 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
712 "DNS hijacking with root `%s' enabled. Connecting to DNS service.\n",
714 GNUNET_free (dns_root_name);
716 GNS_interceptor_init (&dns_root, c))
718 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
722 GNS_resolver_init (namestore_handle, dht_handle,
724 max_parallel_bg_queries);
725 GNS_shorten_init (namestore_handle, dht_handle);
726 GNUNET_SERVER_disconnect_notify (server,
727 ¬ify_client_disconnect,
729 /* Schedule periodic put for our records. */
730 first_zone_iteration = GNUNET_YES;
731 GNUNET_SERVER_add_handlers (server, handlers);
732 statistics = GNUNET_STATISTICS_create ("gns", c);
733 nc = GNUNET_SERVER_notification_context_create (server, 1);
734 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
736 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
737 &shutdown_task, NULL);
742 * The main function for the GNS service.
744 * @param argc number of arguments from the command line
745 * @param argv command line arguments
746 * @return 0 ok, 1 on error
749 main (int argc, char *const *argv)
755 GNUNET_SERVICE_run (argc, argv, "gns", GNUNET_SERVICE_OPTION_NONE, &run,
760 /* end of gnunet-service-gns.c */