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;
290 num_public_records++;
291 if ( (num_public_records > last_num_public_records) &&
292 (GNUNET_NO == first_zone_iteration) )
294 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
295 "Last record count was lower than current record count. Reducing interval.\n");
296 put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
298 next_put_interval = GNUNET_TIME_relative_divide (put_interval,
299 LATE_ITERATION_SPEEDUP_FACTOR);
302 next_put_interval = put_interval;
304 GNUNET_STATISTICS_set (statistics,
305 "Current zone iteration interval (ms)",
306 next_put_interval.rel_value_us / 1000LL,
308 zone_publish_task = GNUNET_SCHEDULER_add_delayed (next_put_interval,
309 &publish_zone_dht_next,
315 * Function used to put all records successively into the DHT.
317 * @param cls the closure (NULL)
318 * @param key the private key of the authority (ours)
319 * @param name the name of the records, NULL once the iteration is done
320 * @param rd_count the number of records in @a rd
321 * @param rd the record data
324 put_gns_record (void *cls,
325 const struct GNUNET_CRYPTO_EccPrivateKey *key,
327 unsigned int rd_count,
328 const struct GNUNET_NAMESTORE_RecordData *rd)
330 struct GNUNET_NAMESTORE_Block *block;
331 struct GNUNET_HashCode query;
332 struct GNUNET_TIME_Absolute expire;
333 struct GNUNET_TIME_Absolute now;
335 struct GNUNET_NAMESTORE_RecordData rd_public[rd_count];
336 unsigned int rd_public_count;
341 /* we're done with one iteration, calculate when to do the next one */
342 namestore_iter = NULL;
343 last_num_public_records = num_public_records;
344 first_zone_iteration = GNUNET_NO;
345 if (0 == num_public_records)
348 * If no records are known (startup) or none present
349 * we can safely set the interval to the value for a single
352 put_interval = zone_publish_time_window;
353 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
354 "No records in namestore database.\n");
358 put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
361 put_interval = GNUNET_TIME_relative_max (MINIMUM_ZONE_ITERATION_INTERVAL,
364 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
365 "Zone iteration finished. Adjusted zone iteration interval to %s\n",
366 GNUNET_STRINGS_relative_time_to_string (put_interval, GNUNET_YES));
367 GNUNET_STATISTICS_set (statistics,
368 "Current zone iteration interval (in ms)",
369 put_interval.rel_value_us / 1000LL,
371 GNUNET_STATISTICS_update (statistics,
372 "Number of zone iterations",
375 GNUNET_STATISTICS_set (statistics,
376 "Number of public records in DHT",
377 last_num_public_records,
379 if (0 == num_public_records)
380 zone_publish_task = GNUNET_SCHEDULER_add_delayed (put_interval,
381 &publish_zone_dht_start,
384 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
389 /* filter out records that are not public, and convert to
390 absolute expiration time. */
392 now = GNUNET_TIME_absolute_get ();
393 for (i=0;i<rd_count;i++)
394 if (0 == (rd[i].flags & (GNUNET_NAMESTORE_RF_PRIVATE |
395 GNUNET_NAMESTORE_RF_PENDING)))
397 rd_public[rd_public_count] = rd[i];
398 if (0 != (rd[i].flags & GNUNET_NAMESTORE_RF_RELATIVE_EXPIRATION))
400 rd_public[rd_public_count].flags &= ~GNUNET_NAMESTORE_RF_RELATIVE_EXPIRATION;
401 rd_public[rd_public_count].expiration_time += now.abs_value_us;
406 /* We got a set of records to publish */
407 if (0 == rd_public_count)
409 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_next,
413 expire = GNUNET_NAMESTORE_record_get_expiration_time (rd_public_count,
415 block = GNUNET_NAMESTORE_block_create (key,
420 block_size = ntohl (block->purpose.size)
421 + sizeof (struct GNUNET_CRYPTO_EccSignature)
422 + sizeof (struct GNUNET_CRYPTO_EccPublicSignKey);
423 GNUNET_NAMESTORE_query_from_private_key (key,
427 active_put = GNUNET_DHT_put (dht_handle, &query,
428 DHT_GNS_REPLICATION_LEVEL,
429 GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE,
430 GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
434 DHT_OPERATION_TIMEOUT,
435 &dht_put_continuation,
437 if (NULL == active_put)
440 dht_put_continuation (NULL, GNUNET_NO);
447 * Periodically iterate over our zone and store everything in dht
450 * @param tc task context
453 publish_zone_dht_start (void *cls,
454 const struct GNUNET_SCHEDULER_TaskContext *tc)
456 zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
458 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
459 "Scheduling DHT zone update!\n");
460 /* start counting again */
461 num_public_records = 0;
462 namestore_iter = GNUNET_NAMESTORE_zone_iteration_start (namestore_handle,
463 NULL, /* All zones */
469 /* END DHT ZONE PROPAGATION */
473 * Reply to client with the result from our lookup.
475 * @param cls the closure (our client lookup handle)
476 * @param rd_count the number of records in @a rd
477 * @param rd the record data
480 send_lookup_response (void* cls,
482 const struct GNUNET_NAMESTORE_RecordData *rd)
484 struct ClientLookupHandle *clh = cls;
485 struct GNUNET_GNS_ClientLookupResultMessage *rmsg;
488 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
489 "Sending `%s' message with %d results\n",
493 len = GNUNET_NAMESTORE_records_get_size (rd_count, rd);
494 rmsg = GNUNET_malloc (len + sizeof (struct GNUNET_GNS_ClientLookupResultMessage));
495 rmsg->header.type = htons (GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT);
496 rmsg->header.size = htons (len + sizeof(struct GNUNET_GNS_ClientLookupResultMessage));
497 rmsg->id = clh->request_id;
498 rmsg->rd_count = htonl (rd_count);
499 GNUNET_NAMESTORE_records_serialize (rd_count, rd, len,
501 GNUNET_SERVER_notification_context_unicast (nc,
506 GNUNET_SERVER_receive_done (clh->client,
508 GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
509 GNUNET_SERVER_client_set_user_context (clh->client, NULL);
511 GNUNET_STATISTICS_update (statistics,
512 "Completed lookups", 1,
514 GNUNET_STATISTICS_update (statistics,
522 * Handle lookup requests from client
524 * @param cls the closure
525 * @param client the client
526 * @param message the message
529 handle_lookup (void *cls,
530 struct GNUNET_SERVER_Client *client,
531 const struct GNUNET_MessageHeader *message)
533 char name[GNUNET_DNSPARSER_MAX_NAME_LENGTH + 1];
534 struct ClientLookupHandle *clh;
535 char *nameptr = name;
537 const struct GNUNET_CRYPTO_EccPrivateKey *key;
539 const struct GNUNET_GNS_ClientLookupMessage *sh_msg;
541 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
542 "Received `%s' message\n",
544 msg_size = ntohs (message->size);
545 if (msg_size < sizeof (struct GNUNET_GNS_ClientLookupMessage))
548 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
551 sh_msg = (const struct GNUNET_GNS_ClientLookupMessage *) message;
552 GNUNET_SERVER_notification_context_add (nc, client);
553 if (GNUNET_YES == ntohl (sh_msg->have_key))
554 key = &sh_msg->shorten_key;
557 utf_in = (const char *) &sh_msg[1];
558 if ( ('\0' != utf_in[msg_size - sizeof (struct GNUNET_GNS_ClientLookupMessage) - 1]) ||
559 (strlen (utf_in) > GNUNET_DNSPARSER_MAX_NAME_LENGTH) )
562 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
565 GNUNET_STRINGS_utf8_tolower (utf_in, &nameptr);
567 clh = GNUNET_new (struct ClientLookupHandle);
568 GNUNET_SERVER_client_set_user_context (client, clh);
569 GNUNET_CONTAINER_DLL_insert (clh_head, clh_tail, clh);
570 clh->client = client;
571 clh->request_id = sh_msg->id;
572 if ( (GNUNET_DNSPARSER_TYPE_A == ntohl (sh_msg->type)) &&
573 (GNUNET_OK != v4_enabled) )
575 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
576 "LOOKUP: Query for A record but AF_INET not supported!");
577 send_lookup_response (clh, 0, NULL);
580 if ( (GNUNET_DNSPARSER_TYPE_AAAA == ntohl (sh_msg->type)) &&
581 (GNUNET_OK != v6_enabled) )
583 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
584 "LOOKUP: Query for AAAA record but AF_INET6 not supported!");
585 send_lookup_response (clh, 0, NULL);
588 clh->lookup = GNS_resolver_lookup (&sh_msg->zone,
589 ntohl (sh_msg->type),
592 ntohl (sh_msg->only_cached),
593 &send_lookup_response, clh);
594 GNUNET_STATISTICS_update (statistics,
601 * One of our clients disconnected, clean up after it.
604 * @param client the client that disconnected
607 notify_client_disconnect (void *cls,
608 struct GNUNET_SERVER_Client *client)
610 struct ClientLookupHandle *clh;
614 clh = GNUNET_SERVER_client_get_user_context (client, struct ClientLookupHandle);
617 GNS_resolver_lookup_cancel (clh->lookup);
618 GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
624 * Process GNS requests.
627 * @param server the initialized server
628 * @param c configuration to use
631 run (void *cls, struct GNUNET_SERVER_Handle *server,
632 const struct GNUNET_CONFIGURATION_Handle *c)
634 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
635 { &handle_lookup, NULL, GNUNET_MESSAGE_TYPE_GNS_LOOKUP, 0},
638 struct GNUNET_CRYPTO_EccPublicSignKey dns_root;
639 unsigned long long max_parallel_bg_queries = 0;
642 v6_enabled = GNUNET_NETWORK_test_pf (PF_INET6);
643 v4_enabled = GNUNET_NETWORK_test_pf (PF_INET);
645 namestore_handle = GNUNET_NAMESTORE_connect (c);
646 if (NULL == namestore_handle)
648 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
649 _("Failed to connect to the namestore!\n"));
650 GNUNET_SCHEDULER_shutdown ();
654 put_interval = INITIAL_PUT_INTERVAL;
655 zone_publish_time_window = DEFAULT_ZONE_PUBLISH_TIME_WINDOW;
658 GNUNET_CONFIGURATION_get_value_time (c, "gns",
659 "ZONE_PUBLISH_TIME_WINDOW",
660 &zone_publish_time_window))
662 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
663 "Time window for zone iteration: %s\n",
664 GNUNET_STRINGS_relative_time_to_string (zone_publish_time_window, GNUNET_YES));
667 GNUNET_CONFIGURATION_get_value_number (c, "gns",
668 "MAX_PARALLEL_BACKGROUND_QUERIES",
669 &max_parallel_bg_queries))
671 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
672 "Number of allowed parallel background queries: %llu\n",
673 max_parallel_bg_queries);
677 GNUNET_CONFIGURATION_get_value_time (c, "gns",
678 "DEFAULT_LOOKUP_TIMEOUT",
679 &default_lookup_timeout))
681 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
682 "Default lookup timeout: %s\n",
683 GNUNET_STRINGS_relative_time_to_string (default_lookup_timeout,
687 dht_handle = GNUNET_DHT_connect (c,
688 (unsigned int) max_parallel_bg_queries);
689 if (NULL == dht_handle)
691 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
692 _("Could not connect to DHT!\n"));
693 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
698 GNUNET_CONFIGURATION_get_value_string (c, "gns", "DNS_ROOT",
702 GNUNET_CRYPTO_ecc_public_sign_key_from_string (dns_root_name,
703 strlen (dns_root_name),
706 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
708 _("valid public key required"));
709 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
710 GNUNET_free (dns_root_name);
713 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
714 "DNS hijacking with root `%s' enabled. Connecting to DNS service.\n",
716 GNUNET_free (dns_root_name);
718 GNS_interceptor_init (&dns_root, c))
720 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
724 GNS_resolver_init (namestore_handle, dht_handle,
726 max_parallel_bg_queries);
727 GNS_shorten_init (namestore_handle, dht_handle);
728 GNUNET_SERVER_disconnect_notify (server,
729 ¬ify_client_disconnect,
731 /* Schedule periodic put for our records. */
732 first_zone_iteration = GNUNET_YES;
733 GNUNET_SERVER_add_handlers (server, handlers);
734 statistics = GNUNET_STATISTICS_create ("gns", c);
735 nc = GNUNET_SERVER_notification_context_create (server, 1);
736 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
738 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
739 &shutdown_task, NULL);
744 * The main function for the GNS service.
746 * @param argc number of arguments from the command line
747 * @param argv command line arguments
748 * @return 0 ok, 1 on error
751 main (int argc, char *const *argv)
757 GNUNET_SERVICE_run (argc, argv, "gns", GNUNET_SERVICE_OPTION_NONE, &run,
762 /* end of gnunet-service-gns.c */