src/gns/gnunet-service-gns.c

   1 /*
   2      This file is part of GNUnet.
   3      (C) 2011-2013 Christian Grothoff (and other contributing authors)
   4
   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.
   9
  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.
  14
  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.
  19 */
  20 /**
  21  * @file gns/gnunet-service-gns.c
  22  * @brief GNUnet GNS service
  23  * @author Martin Schanzenbach
  24  */
  25 #include "platform.h"
  26 #include "gnunet_util_lib.h"
  27 #include "gnunet_transport_service.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"
  34 #include "gns.h"
  35 #include "gns_common.h"
  36 #include "gnunet-service-gns_resolver.h"
  37 #include "gnunet-service-gns_interceptor.h"
  38 #include "gnunet_protocols.h"
  39
  40 /**
  41  * The initial interval in milliseconds btween puts in
  42  * a zone iteration
  43  */
  44 #define INITIAL_PUT_INTERVAL GNUNET_TIME_UNIT_MILLISECONDS
  45
  46 /**
  47  * The upper bound for the zone iteration interval in milliseconds
  48  */
  49 #define MINIMUM_ZONE_ITERATION_INTERVAL GNUNET_TIME_UNIT_SECONDS
  50
  51 /**
  52  * The default put interval for the zone iteration. In case
  53  * no option is found
  54  */
  55 #define DEFAULT_ZONE_PUBLISH_TIME_WINDOW GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 4)
  56
  57 /**
  58  * The factor the current zone iteration interval is divided by for each
  59  * additional new record
  60  */
  61 #define LATE_ITERATION_SPEEDUP_FACTOR 2
  62
  63 /**
  64  * How long until a DHT PUT attempt should time out?
  65  */
  66 #define DHT_OPERATION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 60)
  67
  68 /**
  69  * What replication level do we use for DHT PUT operations?
  70  */
  71 #define DHT_GNS_REPLICATION_LEVEL 5
  72
  73
  74 /**
  75  * Handle to a lookup operation from api
  76  */
  77 struct ClientLookupHandle
  78 {
  79
  80   /**
  81    * We keep these in a DLL.
  82    */
  83   struct ClientLookupHandle *next;
  84
  85   /**
  86    * We keep these in a DLL.
  87    */
  88   struct ClientLookupHandle *prev;
  89
  90   /**
  91    * Handle to the requesting client
  92    */
  93   struct GNUNET_SERVER_Client *client;
  94
  95   /**
  96    * Active handle for the lookup.
  97    */
  98   struct GNS_ResolverHandle *lookup;
  99
 100   /**
 101    * request id
 102    */
 103   uint32_t request_id;
 104
 105 };
 106
 107
 108 /**
 109  * Our handle to the DHT
 110  */
 111 static struct GNUNET_DHT_Handle *dht_handle;
 112
 113 /**
 114  * Active DHT put operation (or NULL)
 115  */
 116 static struct GNUNET_DHT_PutHandle *active_put;
 117
 118 /**
 119  * Our handle to the namestore service
 120  */
 121 static struct GNUNET_NAMESTORE_Handle *namestore_handle;
 122
 123 /**
 124  * Handle to iterate over our authoritative zone in namestore
 125  */
 126 static struct GNUNET_NAMESTORE_ZoneIterator *namestore_iter;
 127
 128 /**
 129  * Our notification context.
 130  */
 131 static struct GNUNET_SERVER_NotificationContext *nc;
 132
 133 /**
 134  * Head of the DLL.
 135  */
 136 static struct ClientLookupHandle *clh_head;
 137
 138 /**
 139  * Tail of the DLL.
 140  */
 141 static struct ClientLookupHandle *clh_tail;
 142
 143 /**
 144  * Useful for zone update for DHT put
 145  */
 146 static unsigned long long num_public_records;
 147
 148 /**
 149  * Last seen record count
 150  */
 151 static unsigned long long last_num_public_records;
 152
 153 /**
 154  * Zone iteration PUT interval.
 155  */
 156 static struct GNUNET_TIME_Relative put_interval;
 157
 158 /**
 159  * Time window for zone iteration
 160  */
 161 static struct GNUNET_TIME_Relative zone_publish_time_window;
 162
 163 /**
 164  * zone publish task
 165  */
 166 static GNUNET_SCHEDULER_TaskIdentifier zone_publish_task;
 167
 168 /**
 169  * #GNUNET_YES if zone has never been published before
 170  */
 171 static int first_zone_iteration;
 172
 173 /**
 174  * The lookup timeout
 175  */
 176 static struct GNUNET_TIME_Relative default_lookup_timeout;
 177
 178 /**
 179  * #GNUNET_YES if ipv6 is supported
 180  */
 181 static int v6_enabled;
 182
 183 /**
 184  * #GNUNET_YES if ipv4 is supported
 185  */
 186 static int v4_enabled;
 187
 188 /**
 189  * Handle to the statistics service
 190  */
 191 static struct GNUNET_STATISTICS_Handle *statistics;
 192
 193
 194 /**
 195  * Task run during shutdown.
 196  *
 197  * @param cls unused
 198  * @param tc unused
 199  */
 200 static void
 201 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 202 {
 203   struct ClientLookupHandle *clh;
 204
 205   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 206               "Shutting down!\n");
 207   GNUNET_SERVER_notification_context_destroy (nc);
 208   while (NULL != (clh = clh_head))
 209   {
 210     GNS_resolver_lookup_cancel (clh->lookup);
 211     GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
 212     GNUNET_free (clh);
 213   }
 214
 215   GNS_interceptor_done ();
 216   GNS_resolver_done ();
 217   if (NULL != statistics)
 218   {
 219     GNUNET_STATISTICS_destroy (statistics, GNUNET_NO);
 220     statistics = NULL;
 221   }
 222   if (GNUNET_SCHEDULER_NO_TASK != zone_publish_task)
 223   {
 224     GNUNET_SCHEDULER_cancel (zone_publish_task);
 225     zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
 226   }
 227   if (NULL != namestore_iter)
 228   {
 229     GNUNET_NAMESTORE_zone_iteration_stop (namestore_iter);
 230     namestore_iter = NULL;
 231   }
 232   if (NULL != namestore_handle)
 233   {
 234     GNUNET_NAMESTORE_disconnect (namestore_handle);
 235     namestore_handle = NULL;
 236   }
 237   if (NULL != active_put)
 238   {
 239     GNUNET_DHT_put_cancel (active_put);
 240     active_put = NULL;
 241   }
 242   if (NULL != dht_handle)
 243   {
 244     GNUNET_DHT_disconnect (dht_handle);
 245     dht_handle = NULL;
 246   }
 247 }
 248
 249
 250 /**
 251  * Method called periodically that triggers iteration over authoritative records
 252  *
 253  * @param cls closure
 254  * @param tc task context
 255  */
 256 static void
 257 publish_zone_dht_next (void *cls,
 258                        const struct GNUNET_SCHEDULER_TaskContext *tc)
 259 {
 260   zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
 261   GNUNET_NAMESTORE_zone_iterator_next (namestore_iter);
 262 }
 263
 264
 265 /**
 266  * Periodically iterate over our zone and store everything in dht
 267  *
 268  * @param cls NULL
 269  * @param tc task context
 270  */
 271 static void
 272 publish_zone_dht_start (void *cls,
 273                         const struct GNUNET_SCHEDULER_TaskContext *tc);
 274
 275
 276 /**
 277  * Continuation called from DHT once the PUT operation is done.
 278  *
 279  * @param cls closure, NULL
 280  * @param success #GNUNET_OK on success
 281  */
 282 static void
 283 dht_put_continuation (void *cls,
 284                       int success)
 285 {
 286   struct GNUNET_TIME_Relative next_put_interval;
 287
 288   num_public_records++;
 289   if ( (num_public_records > last_num_public_records) &&
 290        (GNUNET_NO == first_zone_iteration) )
 291   {
 292     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 293                 "Last record count was lower than current record count.  Reducing interval.\n");
 294     put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
 295                                                 num_public_records);
 296     next_put_interval = GNUNET_TIME_relative_divide (put_interval,
 297                                                      LATE_ITERATION_SPEEDUP_FACTOR);
 298   }
 299   else
 300     next_put_interval = put_interval;
 301
 302   GNUNET_STATISTICS_set (statistics,
 303                          "Current zone iteration interval (ms)",
 304                          next_put_interval.rel_value_us / 1000LL,
 305                          GNUNET_NO);
 306   zone_publish_task = GNUNET_SCHEDULER_add_delayed (next_put_interval,
 307                                                     &publish_zone_dht_next,
 308                                                     NULL);
 309 }
 310
 311
 312 /**
 313  * Function used to put all records successively into the DHT.
 314  *
 315  * @param cls the closure (NULL)
 316  * @param key the private key of the authority (ours)
 317  * @param name the name of the records, NULL once the iteration is done
 318  * @param rd_count the number of records in @a rd
 319  * @param rd the record data
 320  */
 321 static void
 322 put_gns_record (void *cls,
 323                 const struct GNUNET_CRYPTO_EccPrivateKey *key,
 324                 const char *name,
 325                 unsigned int rd_count,
 326                 const struct GNUNET_NAMESTORE_RecordData *rd)
 327 {
 328   struct GNUNET_NAMESTORE_Block *block;
 329   struct GNUNET_HashCode query;
 330   struct GNUNET_TIME_Absolute expire;
 331   size_t block_size;
 332
 333   if (NULL == name)
 334   {
 335     /* we're done with one iteration, calculate when to do the next one */
 336     namestore_iter = NULL;
 337     last_num_public_records = num_public_records;
 338     first_zone_iteration = GNUNET_NO;
 339     if (0 == num_public_records)
 340     {
 341       /**
 342        * If no records are known (startup) or none present
 343        * we can safely set the interval to the value for a single
 344        * record
 345        */
 346       put_interval = zone_publish_time_window;
 347       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
 348                   "No records in namestore database.\n");
 349     }
 350     else
 351     {
 352       put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
 353                                                   num_public_records);
 354     }
 355     put_interval = GNUNET_TIME_relative_max (MINIMUM_ZONE_ITERATION_INTERVAL,
 356                                              put_interval);
 357
 358     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 359                 "Zone iteration finished. Adjusted zone iteration interval to %s\n",
 360                 GNUNET_STRINGS_relative_time_to_string (put_interval, GNUNET_YES));
 361     GNUNET_STATISTICS_set (statistics,
 362                            "Current zone iteration interval (in ms)",
 363                            put_interval.rel_value_us / 1000LL,
 364                            GNUNET_NO);
 365     GNUNET_STATISTICS_update (statistics,
 366                               "Number of zone iterations",
 367                               1,
 368                               GNUNET_NO);
 369     GNUNET_STATISTICS_set (statistics,
 370                            "Number of public records in DHT",
 371                            last_num_public_records,
 372                            GNUNET_NO);
 373     if (0 == num_public_records)
 374       zone_publish_task = GNUNET_SCHEDULER_add_delayed (put_interval,
 375                                                         &publish_zone_dht_start,
 376                                                         NULL);
 377     else
 378       zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
 379                                                     NULL);
 380     return;
 381   }
 382
 383   /* FIXME: filter out records that are not public! */
 384
 385   /* We got a set of records to publish */
 386   if (0 == rd_count)
 387   {
 388     zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_next,
 389                                                    NULL);
 390     return;
 391   }
 392   expire = GNUNET_NAMESTORE_record_get_expiration_time (rd_count,
 393                                                         rd);
 394   block = GNUNET_NAMESTORE_block_create (key,
 395                                          expire,
 396                                          name,
 397                                          rd,
 398                                          rd_count);
 399   block_size = ntohl (block->purpose.size)
 400     + sizeof (struct GNUNET_CRYPTO_EccSignature)
 401     + sizeof (struct GNUNET_CRYPTO_EccPublicKey);
 402   GNUNET_NAMESTORE_query_from_private_key (key,
 403                                            name,
 404                                            &query);
 405
 406   active_put = GNUNET_DHT_put (dht_handle, &query,
 407                                DHT_GNS_REPLICATION_LEVEL,
 408                                GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE,
 409                                GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
 410                                block_size,
 411                                block,
 412                                expire,
 413                                DHT_OPERATION_TIMEOUT,
 414                                &dht_put_continuation,
 415                                NULL);
 416   if (NULL == active_put)
 417   {
 418     GNUNET_break (0);
 419     dht_put_continuation (NULL, GNUNET_NO);
 420   }
 421   GNUNET_free (block);
 422 }
 423
 424
 425 /**
 426  * Periodically iterate over our zone and store everything in dht
 427  *
 428  * @param cls NULL
 429  * @param tc task context
 430  */
 431 static void
 432 publish_zone_dht_start (void *cls,
 433                         const struct GNUNET_SCHEDULER_TaskContext *tc)
 434 {
 435   zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
 436
 437   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 438               "Scheduling DHT zone update!\n");
 439   /* start counting again */
 440   num_public_records = 0;
 441   namestore_iter = GNUNET_NAMESTORE_zone_iteration_start (namestore_handle,
 442                                                           NULL, /* All zones */
 443                                                           &put_gns_record,
 444                                                           NULL);
 445 }
 446
 447
 448 /* END DHT ZONE PROPAGATION */
 449
 450
 451 /**
 452  * Reply to client with the result from our lookup.
 453  *
 454  * @param cls the closure (our client lookup handle)
 455  * @param rd_count the number of records
 456  * @param rd the record data
 457  */
 458 static void
 459 send_lookup_response (void* cls,
 460                       uint32_t rd_count,
 461                       const struct GNUNET_NAMESTORE_RecordData *rd)
 462 {
 463   struct ClientLookupHandle *clh = cls;
 464   struct GNUNET_GNS_ClientLookupResultMessage *rmsg;
 465   size_t len;
 466
 467   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 468               "Sending `%s' message with %d results\n",
 469               "LOOKUP_RESULT",
 470               rd_count);
 471
 472   len = GNUNET_NAMESTORE_records_get_size (rd_count, rd);
 473   rmsg = GNUNET_malloc (len + sizeof (struct GNUNET_GNS_ClientLookupResultMessage));
 474   rmsg->header.type = htons (GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT);
 475   rmsg->header.size = htons (len + sizeof(struct GNUNET_GNS_ClientLookupResultMessage));
 476   rmsg->id = clh->request_id;
 477   rmsg->rd_count = htonl (rd_count);
 478   GNUNET_NAMESTORE_records_serialize (rd_count, rd, len,
 479                                       (char*) &rmsg[1]);
 480   GNUNET_SERVER_notification_context_unicast (nc,
 481                                               clh->client,
 482                                               &rmsg->header,
 483                                               GNUNET_NO);
 484   GNUNET_free (rmsg);
 485   GNUNET_SERVER_receive_done (clh->client,
 486                               GNUNET_OK);
 487   GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
 488   GNUNET_free (clh);
 489   GNUNET_STATISTICS_update (statistics,
 490                             "Completed lookups", 1,
 491                             GNUNET_NO);
 492   GNUNET_STATISTICS_update (statistics,
 493                             "Records resolved",
 494                             rd_count,
 495                             GNUNET_NO);
 496 }
 497
 498
 499 /**
 500  * Handle lookup requests from client
 501  *
 502  * @param cls the closure
 503  * @param client the client
 504  * @param message the message
 505  */
 506 static void
 507 handle_lookup (void *cls,
 508                struct GNUNET_SERVER_Client *client,
 509                const struct GNUNET_MessageHeader *message)
 510 {
 511   char name[GNUNET_DNSPARSER_MAX_NAME_LENGTH + 1];
 512   struct ClientLookupHandle *clh;
 513   char *nameptr = name;
 514   const char *utf_in;
 515   const struct GNUNET_CRYPTO_EccPrivateKey *key;
 516   uint16_t msg_size;
 517   const struct GNUNET_GNS_ClientLookupMessage *sh_msg;
 518
 519   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 520               "Received `%s' message\n",
 521               "LOOKUP");
 522   msg_size = ntohs (message->size);
 523   if (msg_size < sizeof (struct GNUNET_GNS_ClientLookupMessage))
 524   {
 525     GNUNET_break (0);
 526     GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
 527     return;
 528   }
 529   sh_msg = (const struct GNUNET_GNS_ClientLookupMessage *) message;
 530   GNUNET_SERVER_notification_context_add (nc, client);
 531   if (GNUNET_YES == ntohl (sh_msg->have_key))
 532     key = &sh_msg->shorten_key;
 533   else
 534     key = NULL;
 535   utf_in = (const char *) &sh_msg[1];
 536   if ( ('\0' != utf_in[msg_size - sizeof (struct GNUNET_GNS_ClientLookupMessage) - 1]) ||
 537        (strlen (utf_in) > GNUNET_DNSPARSER_MAX_NAME_LENGTH) )
 538   {
 539     GNUNET_break (0);
 540     GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
 541     return;
 542   }
 543   GNUNET_STRINGS_utf8_tolower (utf_in, &nameptr);
 544
 545   clh = GNUNET_new (struct ClientLookupHandle);
 546   GNUNET_CONTAINER_DLL_insert (clh_head, clh_tail, clh);
 547   clh->client = client;
 548   clh->request_id = sh_msg->id;
 549   if ( (GNUNET_DNSPARSER_TYPE_A == ntohl (sh_msg->type)) &&
 550        (GNUNET_OK != v4_enabled) )
 551   {
 552     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 553                 "LOOKUP: Query for A record but AF_INET not supported!");
 554     send_lookup_response (clh, 0, NULL);
 555     return;
 556   }
 557   if ( (GNUNET_DNSPARSER_TYPE_AAAA == ntohl (sh_msg->type)) &&
 558        (GNUNET_OK != v6_enabled) )
 559   {
 560     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 561                 "LOOKUP: Query for AAAA record but AF_INET6 not supported!");
 562     send_lookup_response (clh, 0, NULL);
 563     return;
 564   }
 565   clh->lookup = GNS_resolver_lookup (&sh_msg->zone,
 566                                      ntohl (sh_msg->type),
 567                                      name,
 568                                      key,
 569                                      ntohl (sh_msg->only_cached),
 570                                      &send_lookup_response, clh);
 571   GNUNET_STATISTICS_update (statistics,
 572                             "Lookup attempts",
 573                             1, GNUNET_NO);
 574 }
 575
 576
 577 /**
 578  * Process GNS requests.
 579  *
 580  * @param cls closure
 581  * @param server the initialized server
 582  * @param c configuration to use
 583  */
 584 static void
 585 run (void *cls, struct GNUNET_SERVER_Handle *server,
 586      const struct GNUNET_CONFIGURATION_Handle *c)
 587 {
 588   static const struct GNUNET_SERVER_MessageHandler handlers[] = {
 589     { &handle_lookup, NULL, GNUNET_MESSAGE_TYPE_GNS_LOOKUP, 0},
 590     {NULL, NULL, 0, 0}
 591   };
 592   struct GNUNET_CRYPTO_EccPublicKey dns_root;
 593   unsigned long long max_parallel_bg_queries = 0;
 594   int ignore_pending = GNUNET_NO;
 595   char *dns_root_name;
 596
 597   v6_enabled = GNUNET_NETWORK_test_pf (PF_INET6);
 598   v4_enabled = GNUNET_NETWORK_test_pf (PF_INET);
 599
 600   namestore_handle = GNUNET_NAMESTORE_connect (c);
 601   if (NULL == namestore_handle)
 602   {
 603     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 604                 _("Failed to connect to the namestore!\n"));
 605     GNUNET_SCHEDULER_shutdown ();
 606     return;
 607   }
 608
 609   put_interval = INITIAL_PUT_INTERVAL;
 610   zone_publish_time_window = DEFAULT_ZONE_PUBLISH_TIME_WINDOW;
 611
 612   if (GNUNET_OK ==
 613       GNUNET_CONFIGURATION_get_value_time (c, "gns",
 614                                            "ZONE_PUBLISH_TIME_WINDOW",
 615                                            &zone_publish_time_window))
 616   {
 617     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 618                 "Time window for zone iteration: %s\n",
 619                 GNUNET_STRINGS_relative_time_to_string (zone_publish_time_window, GNUNET_YES));
 620   }
 621   if (GNUNET_OK ==
 622       GNUNET_CONFIGURATION_get_value_number (c, "gns",
 623                                             "MAX_PARALLEL_BACKGROUND_QUERIES",
 624                                             &max_parallel_bg_queries))
 625   {
 626     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 627                 "Number of allowed parallel background queries: %llu\n",
 628                 max_parallel_bg_queries);
 629   }
 630
 631   if (GNUNET_YES ==
 632       GNUNET_CONFIGURATION_get_value_yesno (c, "gns",
 633                                             "AUTO_IMPORT_CONFIRMATION_REQ"))
 634   {
 635     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 636                 "Auto import requires user confirmation\n");
 637     ignore_pending = GNUNET_YES;
 638   }
 639
 640   if (GNUNET_OK ==
 641       GNUNET_CONFIGURATION_get_value_time (c, "gns",
 642                                            "DEFAULT_LOOKUP_TIMEOUT",
 643                                            &default_lookup_timeout))
 644   {
 645     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 646                 "Default lookup timeout: %s\n",
 647                 GNUNET_STRINGS_relative_time_to_string (default_lookup_timeout,
 648                                                         GNUNET_YES));
 649   }
 650
 651   dht_handle = GNUNET_DHT_connect (c,
 652                                    (unsigned int) max_parallel_bg_queries);
 653   if (NULL == dht_handle)
 654   {
 655     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 656                 _("Could not connect to DHT!\n"));
 657     GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
 658     return;
 659   }
 660
 661   if (GNUNET_SYSERR ==
 662       GNS_resolver_init (namestore_handle, dht_handle,
 663                          c,
 664                          max_parallel_bg_queries,
 665                          ignore_pending))
 666   {
 667     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 668                 _("Unable to initialize resolver!\n"));
 669     GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
 670     return;
 671   }
 672
 673   if (GNUNET_OK ==
 674       GNUNET_CONFIGURATION_get_value_string (c, "gns", "DNS_ROOT",
 675                                              &dns_root_name))
 676   {
 677     if (GNUNET_OK !=
 678         GNUNET_CRYPTO_ecc_public_key_from_string (dns_root_name,
 679                                                   strlen (dns_root_name),
 680                                                   &dns_root))
 681     {
 682       GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
 683                                  "gns", "DNS_ROOT",
 684                                  _("valid public key required"));
 685       GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
 686       GNUNET_free (dns_root_name);
 687       return;
 688     }
 689     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
 690                 "DNS hijacking with root `%s' enabled. Connecting to DNS service.\n",
 691                 dns_root_name);
 692     GNUNET_free (dns_root_name);
 693     if (GNUNET_SYSERR ==
 694         GNS_interceptor_init (&dns_root, c))
 695     {
 696       GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
 697       return;
 698     }
 699   }
 700   /* FIXME: install client disconnect handle to clean up pending
 701      lookups on client disconnect! */
 702
 703   /* Schedule periodic put for our records. */
 704   first_zone_iteration = GNUNET_YES;
 705   GNUNET_SERVER_add_handlers (server, handlers);
 706   statistics = GNUNET_STATISTICS_create ("gns", c);
 707   nc = GNUNET_SERVER_notification_context_create (server, 1);
 708   zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
 709                                                 NULL);
 710   GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
 711                                 &shutdown_task, NULL);
 712 }
 713
 714
 715 /**
 716  * The main function for the GNS service.
 717  *
 718  * @param argc number of arguments from the command line
 719  * @param argv command line arguments
 720  * @return 0 ok, 1 on error
 721  */
 722 int
 723 main (int argc, char *const *argv)
 724 {
 725   int ret;
 726
 727   ret =
 728       (GNUNET_OK ==
 729        GNUNET_SERVICE_run (argc, argv, "gns", GNUNET_SERVICE_OPTION_NONE, &run,
 730                            NULL)) ? 0 : 1;
 731   return ret;
 732 }
 733
 734 /* end of gnunet-service-gns.c */