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 GNUnet GNS service
23 * @author Martin Schanzenbach
24 * @author Christian Grothoff
27 * - conversion of private to public records does NOT check if the
28 * records are actually public
29 * - need to watch for client disconnects and abort operations on
33 #include "gnunet_util_lib.h"
34 #include "gnunet_transport_service.h"
35 #include "gnunet_dns_service.h"
36 #include "gnunet_dnsparser_lib.h"
37 #include "gnunet_dht_service.h"
38 #include "gnunet_namestore_service.h"
39 #include "gnunet_gns_service.h"
40 #include "gnunet_statistics_service.h"
42 #include "gns_common.h"
43 #include "gnunet-service-gns_resolver.h"
44 #include "gnunet-service-gns_interceptor.h"
45 #include "gnunet_protocols.h"
48 * The initial interval in milliseconds btween puts in
51 #define INITIAL_PUT_INTERVAL GNUNET_TIME_UNIT_MILLISECONDS
54 * The upper bound for the zone iteration interval in milliseconds
56 #define MINIMUM_ZONE_ITERATION_INTERVAL GNUNET_TIME_UNIT_SECONDS
59 * The default put interval for the zone iteration. In case
62 #define DEFAULT_ZONE_PUBLISH_TIME_WINDOW GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 4)
65 * The factor the current zone iteration interval is divided by for each
66 * additional new record
68 #define LATE_ITERATION_SPEEDUP_FACTOR 2
71 * How long until a DHT PUT attempt should time out?
73 #define DHT_OPERATION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 60)
76 * What replication level do we use for DHT PUT operations?
78 #define DHT_GNS_REPLICATION_LEVEL 5
82 * Handle to a lookup operation from api
84 struct ClientLookupHandle
88 * We keep these in a DLL.
90 struct ClientLookupHandle *next;
93 * We keep these in a DLL.
95 struct ClientLookupHandle *prev;
98 * Handle to the requesting client
100 struct GNUNET_SERVER_Client *client;
103 * Active handle for the lookup.
105 struct GNS_ResolverHandle *lookup;
116 * Our handle to the DHT
118 static struct GNUNET_DHT_Handle *dht_handle;
121 * Active DHT put operation (or NULL)
123 static struct GNUNET_DHT_PutHandle *active_put;
126 * Our handle to the namestore service
128 static struct GNUNET_NAMESTORE_Handle *namestore_handle;
131 * Handle to iterate over our authoritative zone in namestore
133 static struct GNUNET_NAMESTORE_ZoneIterator *namestore_iter;
136 * Our notification context.
138 static struct GNUNET_SERVER_NotificationContext *nc;
143 static struct ClientLookupHandle *clh_head;
148 static struct ClientLookupHandle *clh_tail;
151 * Useful for zone update for DHT put
153 static unsigned long long num_public_records;
156 * Last seen record count
158 static unsigned long long last_num_public_records;
161 * Zone iteration PUT interval.
163 static struct GNUNET_TIME_Relative put_interval;
166 * Time window for zone iteration
168 static struct GNUNET_TIME_Relative zone_publish_time_window;
173 static GNUNET_SCHEDULER_TaskIdentifier zone_publish_task;
176 * #GNUNET_YES if zone has never been published before
178 static int first_zone_iteration;
183 static struct GNUNET_TIME_Relative default_lookup_timeout;
186 * #GNUNET_YES if ipv6 is supported
188 static int v6_enabled;
191 * #GNUNET_YES if ipv4 is supported
193 static int v4_enabled;
196 * Handle to the statistics service
198 static struct GNUNET_STATISTICS_Handle *statistics;
202 * Task run during shutdown.
208 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
210 struct ClientLookupHandle *clh;
212 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
214 GNUNET_SERVER_notification_context_destroy (nc);
215 while (NULL != (clh = clh_head))
217 GNS_resolver_lookup_cancel (clh->lookup);
218 GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
222 GNS_interceptor_done ();
223 GNS_resolver_done ();
224 if (NULL != statistics)
226 GNUNET_STATISTICS_destroy (statistics, GNUNET_NO);
229 if (GNUNET_SCHEDULER_NO_TASK != zone_publish_task)
231 GNUNET_SCHEDULER_cancel (zone_publish_task);
232 zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
234 if (NULL != namestore_iter)
236 GNUNET_NAMESTORE_zone_iteration_stop (namestore_iter);
237 namestore_iter = NULL;
239 if (NULL != namestore_handle)
241 GNUNET_NAMESTORE_disconnect (namestore_handle);
242 namestore_handle = NULL;
244 if (NULL != active_put)
246 GNUNET_DHT_put_cancel (active_put);
249 if (NULL != dht_handle)
251 GNUNET_DHT_disconnect (dht_handle);
258 * Method called periodically that triggers iteration over authoritative records
261 * @param tc task context
264 publish_zone_dht_next (void *cls,
265 const struct GNUNET_SCHEDULER_TaskContext *tc)
267 zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
268 GNUNET_NAMESTORE_zone_iterator_next (namestore_iter);
273 * Periodically iterate over our zone and store everything in dht
276 * @param tc task context
279 publish_zone_dht_start (void *cls,
280 const struct GNUNET_SCHEDULER_TaskContext *tc);
284 * Continuation called from DHT once the PUT operation is done.
286 * @param cls closure, NULL
287 * @param success #GNUNET_OK on success
290 dht_put_continuation (void *cls,
293 struct GNUNET_TIME_Relative next_put_interval;
295 num_public_records++;
296 if ( (num_public_records > last_num_public_records) &&
297 (GNUNET_NO == first_zone_iteration) )
299 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
300 "Last record count was lower than current record count. Reducing interval.\n");
301 put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
303 next_put_interval = GNUNET_TIME_relative_divide (put_interval,
304 LATE_ITERATION_SPEEDUP_FACTOR);
307 next_put_interval = put_interval;
309 GNUNET_STATISTICS_set (statistics,
310 "Current zone iteration interval (ms)",
311 next_put_interval.rel_value_us / 1000LL,
313 zone_publish_task = GNUNET_SCHEDULER_add_delayed (next_put_interval,
314 &publish_zone_dht_next,
320 * Function used to put all records successively into the DHT.
322 * @param cls the closure (NULL)
323 * @param key the private key of the authority (ours)
324 * @param name the name of the records, NULL once the iteration is done
325 * @param rd_count the number of records in @a rd
326 * @param rd the record data
329 put_gns_record (void *cls,
330 const struct GNUNET_CRYPTO_EccPrivateKey *key,
332 unsigned int rd_count,
333 const struct GNUNET_NAMESTORE_RecordData *rd)
335 struct GNUNET_NAMESTORE_Block *block;
336 struct GNUNET_HashCode query;
337 struct GNUNET_TIME_Absolute expire;
342 /* we're done with one iteration, calculate when to do the next one */
343 namestore_iter = NULL;
344 last_num_public_records = num_public_records;
345 first_zone_iteration = GNUNET_NO;
346 if (0 == num_public_records)
349 * If no records are known (startup) or none present
350 * we can safely set the interval to the value for a single
353 put_interval = zone_publish_time_window;
354 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
355 "No records in namestore database.\n");
359 put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
362 put_interval = GNUNET_TIME_relative_max (MINIMUM_ZONE_ITERATION_INTERVAL,
365 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
366 "Zone iteration finished. Adjusted zone iteration interval to %s\n",
367 GNUNET_STRINGS_relative_time_to_string (put_interval, GNUNET_YES));
368 GNUNET_STATISTICS_set (statistics,
369 "Current zone iteration interval (in ms)",
370 put_interval.rel_value_us / 1000LL,
372 GNUNET_STATISTICS_update (statistics,
373 "Number of zone iterations",
376 GNUNET_STATISTICS_set (statistics,
377 "Number of public records in DHT",
378 last_num_public_records,
380 if (0 == num_public_records)
381 zone_publish_task = GNUNET_SCHEDULER_add_delayed (put_interval,
382 &publish_zone_dht_start,
385 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
390 /* FIXME: filter out records that are not public! */
392 /* We got a set of records to publish */
395 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_next,
399 expire = GNUNET_NAMESTORE_record_get_expiration_time (rd_count,
401 block = GNUNET_NAMESTORE_block_create (key,
406 block_size = ntohl (block->purpose.size)
407 + sizeof (struct GNUNET_CRYPTO_EccSignature)
408 + sizeof (struct GNUNET_CRYPTO_EccPublicKey);
409 GNUNET_NAMESTORE_query_from_private_key (key,
413 active_put = GNUNET_DHT_put (dht_handle, &query,
414 DHT_GNS_REPLICATION_LEVEL,
415 GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE,
416 GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
420 DHT_OPERATION_TIMEOUT,
421 &dht_put_continuation,
423 if (NULL == active_put)
426 dht_put_continuation (NULL, GNUNET_NO);
433 * Periodically iterate over our zone and store everything in dht
436 * @param tc task context
439 publish_zone_dht_start (void *cls,
440 const struct GNUNET_SCHEDULER_TaskContext *tc)
442 zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
444 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
445 "Scheduling DHT zone update!\n");
446 /* start counting again */
447 num_public_records = 0;
448 namestore_iter = GNUNET_NAMESTORE_zone_iteration_start (namestore_handle,
449 NULL, /* All zones */
455 /* END DHT ZONE PROPAGATION */
459 * Reply to client with the result from our lookup.
461 * @param cls the closure (our client lookup handle)
462 * @param rd_count the number of records
463 * @param rd the record data
466 send_lookup_response (void* cls,
468 const struct GNUNET_NAMESTORE_RecordData *rd)
470 struct ClientLookupHandle *clh = cls;
471 struct GNUNET_GNS_ClientLookupResultMessage *rmsg;
474 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
475 "Sending `%s' message with %d results\n",
479 len = GNUNET_NAMESTORE_records_get_size (rd_count, rd);
480 rmsg = GNUNET_malloc (len + sizeof (struct GNUNET_GNS_ClientLookupResultMessage));
481 rmsg->header.type = htons (GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT);
482 rmsg->header.size = htons (len + sizeof(struct GNUNET_GNS_ClientLookupResultMessage));
483 rmsg->id = clh->request_id;
484 rmsg->rd_count = htonl (rd_count);
485 GNUNET_NAMESTORE_records_serialize (rd_count, rd, len,
487 GNUNET_SERVER_notification_context_unicast (nc,
492 GNUNET_SERVER_receive_done (clh->client,
494 GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
496 GNUNET_STATISTICS_update (statistics,
497 "Completed lookups", 1,
499 GNUNET_STATISTICS_update (statistics,
507 * Handle lookup requests from client
509 * @param cls the closure
510 * @param client the client
511 * @param message the message
514 handle_lookup (void *cls,
515 struct GNUNET_SERVER_Client *client,
516 const struct GNUNET_MessageHeader *message)
518 char name[GNUNET_DNSPARSER_MAX_NAME_LENGTH + 1];
519 struct ClientLookupHandle *clh;
520 char *nameptr = name;
522 const struct GNUNET_CRYPTO_EccPrivateKey *key;
524 const struct GNUNET_GNS_ClientLookupMessage *sh_msg;
526 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
527 "Received `%s' message\n",
529 msg_size = ntohs (message->size);
530 if (msg_size < sizeof (struct GNUNET_GNS_ClientLookupMessage))
533 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
536 sh_msg = (const struct GNUNET_GNS_ClientLookupMessage *) message;
537 GNUNET_SERVER_notification_context_add (nc, client);
538 if (GNUNET_YES == ntohl (sh_msg->have_key))
539 key = &sh_msg->shorten_key;
542 utf_in = (const char *) &sh_msg[1];
543 if ( ('\0' != utf_in[msg_size - sizeof (struct GNUNET_GNS_ClientLookupMessage) - 1]) ||
544 (strlen (utf_in) > GNUNET_DNSPARSER_MAX_NAME_LENGTH) )
547 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
550 GNUNET_STRINGS_utf8_tolower (utf_in, &nameptr);
552 clh = GNUNET_new (struct ClientLookupHandle);
553 GNUNET_CONTAINER_DLL_insert (clh_head, clh_tail, clh);
554 clh->client = client;
555 clh->request_id = sh_msg->id;
556 if ( (GNUNET_DNSPARSER_TYPE_A == ntohl (sh_msg->type)) &&
557 (GNUNET_OK != v4_enabled) )
559 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
560 "LOOKUP: Query for A record but AF_INET not supported!");
561 send_lookup_response (clh, 0, NULL);
564 if ( (GNUNET_DNSPARSER_TYPE_AAAA == ntohl (sh_msg->type)) &&
565 (GNUNET_OK != v6_enabled) )
567 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
568 "LOOKUP: Query for AAAA record but AF_INET6 not supported!");
569 send_lookup_response (clh, 0, NULL);
572 clh->lookup = GNS_resolver_lookup (&sh_msg->zone,
573 ntohl (sh_msg->type),
576 ntohl (sh_msg->only_cached),
577 &send_lookup_response, clh);
578 GNUNET_STATISTICS_update (statistics,
585 * Process GNS requests.
588 * @param server the initialized server
589 * @param c configuration to use
592 run (void *cls, struct GNUNET_SERVER_Handle *server,
593 const struct GNUNET_CONFIGURATION_Handle *c)
595 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
596 { &handle_lookup, NULL, GNUNET_MESSAGE_TYPE_GNS_LOOKUP, 0},
599 struct GNUNET_CRYPTO_EccPublicKey dns_root;
600 unsigned long long max_parallel_bg_queries = 0;
603 v6_enabled = GNUNET_NETWORK_test_pf (PF_INET6);
604 v4_enabled = GNUNET_NETWORK_test_pf (PF_INET);
606 namestore_handle = GNUNET_NAMESTORE_connect (c);
607 if (NULL == namestore_handle)
609 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
610 _("Failed to connect to the namestore!\n"));
611 GNUNET_SCHEDULER_shutdown ();
615 put_interval = INITIAL_PUT_INTERVAL;
616 zone_publish_time_window = DEFAULT_ZONE_PUBLISH_TIME_WINDOW;
619 GNUNET_CONFIGURATION_get_value_time (c, "gns",
620 "ZONE_PUBLISH_TIME_WINDOW",
621 &zone_publish_time_window))
623 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
624 "Time window for zone iteration: %s\n",
625 GNUNET_STRINGS_relative_time_to_string (zone_publish_time_window, GNUNET_YES));
628 GNUNET_CONFIGURATION_get_value_number (c, "gns",
629 "MAX_PARALLEL_BACKGROUND_QUERIES",
630 &max_parallel_bg_queries))
632 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
633 "Number of allowed parallel background queries: %llu\n",
634 max_parallel_bg_queries);
638 GNUNET_CONFIGURATION_get_value_time (c, "gns",
639 "DEFAULT_LOOKUP_TIMEOUT",
640 &default_lookup_timeout))
642 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
643 "Default lookup timeout: %s\n",
644 GNUNET_STRINGS_relative_time_to_string (default_lookup_timeout,
648 dht_handle = GNUNET_DHT_connect (c,
649 (unsigned int) max_parallel_bg_queries);
650 if (NULL == dht_handle)
652 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
653 _("Could not connect to DHT!\n"));
654 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
659 GNUNET_CONFIGURATION_get_value_string (c, "gns", "DNS_ROOT",
663 GNUNET_CRYPTO_ecc_public_key_from_string (dns_root_name,
664 strlen (dns_root_name),
667 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
669 _("valid public key required"));
670 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
671 GNUNET_free (dns_root_name);
674 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
675 "DNS hijacking with root `%s' enabled. Connecting to DNS service.\n",
677 GNUNET_free (dns_root_name);
679 GNS_interceptor_init (&dns_root, c))
681 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
685 /* FIXME: install client disconnect handle to clean up pending
686 lookups on client disconnect! */
687 GNS_resolver_init (namestore_handle, dht_handle,
689 max_parallel_bg_queries);
691 /* Schedule periodic put for our records. */
692 first_zone_iteration = GNUNET_YES;
693 GNUNET_SERVER_add_handlers (server, handlers);
694 statistics = GNUNET_STATISTICS_create ("gns", c);
695 nc = GNUNET_SERVER_notification_context_create (server, 1);
696 zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
698 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
699 &shutdown_task, NULL);
704 * The main function for the GNS service.
706 * @param argc number of arguments from the command line
707 * @param argv command line arguments
708 * @return 0 ok, 1 on error
711 main (int argc, char *const *argv)
717 GNUNET_SERVICE_run (argc, argv, "gns", GNUNET_SERVICE_OPTION_NONE, &run,
722 /* end of gnunet-service-gns.c */