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 GNU Name System (main service)
  23  * @author Martin Schanzenbach
  24  * @author Christian Grothoff
  25  */
  26 #include "platform.h"
  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"
  35 #include "gns.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"
  40
  41 /**
  42  * The initial interval in milliseconds btween puts in
  43  * a zone iteration
  44  */
  45 #define INITIAL_PUT_INTERVAL GNUNET_TIME_UNIT_MILLISECONDS
  46
  47 /**
  48  * The upper bound for the zone iteration interval in milliseconds
  49  */
  50 #define MINIMUM_ZONE_ITERATION_INTERVAL GNUNET_TIME_UNIT_SECONDS
  51
  52 /**
  53  * The default put interval for the zone iteration. In case
  54  * no option is found
  55  */
  56 #define DEFAULT_ZONE_PUBLISH_TIME_WINDOW GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 4)
  57
  58 /**
  59  * The factor the current zone iteration interval is divided by for each
  60  * additional new record
  61  */
  62 #define LATE_ITERATION_SPEEDUP_FACTOR 2
  63
  64 /**
  65  * How long until a DHT PUT attempt should time out?
  66  */
  67 #define DHT_OPERATION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 60)
  68
  69 /**
  70  * What replication level do we use for DHT PUT operations?
  71  */
  72 #define DHT_GNS_REPLICATION_LEVEL 5
  73
  74
  75 /**
  76  * Handle to a lookup operation from api
  77  */
  78 struct ClientLookupHandle
  79 {
  80
  81   /**
  82    * We keep these in a DLL.
  83    */
  84   struct ClientLookupHandle *next;
  85
  86   /**
  87    * We keep these in a DLL.
  88    */
  89   struct ClientLookupHandle *prev;
  90
  91   /**
  92    * Handle to the requesting client
  93    */
  94   struct GNUNET_SERVER_Client *client;
  95
  96   /**
  97    * Active handle for the lookup.
  98    */
  99   struct GNS_ResolverHandle *lookup;
 100
 101   /**
 102    * request id
 103    */
 104   uint32_t request_id;
 105
 106 };
 107
 108
 109 /**
 110  * Our handle to the DHT
 111  */
 112 static struct GNUNET_DHT_Handle *dht_handle;
 113
 114 /**
 115  * Active DHT put operation (or NULL)
 116  */
 117 static struct GNUNET_DHT_PutHandle *active_put;
 118
 119 /**
 120  * Our handle to the namestore service
 121  */
 122 static struct GNUNET_NAMESTORE_Handle *namestore_handle;
 123
 124 /**
 125  * Our handle to the namecache service
 126  */
 127 static struct GNUNET_NAMECACHE_Handle *namecache_handle;
 128
 129 /**
 130  * Handle to iterate over our authoritative zone in namestore
 131  */
 132 static struct GNUNET_NAMESTORE_ZoneIterator *namestore_iter;
 133
 134 /**
 135  * Our notification context.
 136  */
 137 static struct GNUNET_SERVER_NotificationContext *nc;
 138
 139 /**
 140  * Head of the DLL.
 141  */
 142 static struct ClientLookupHandle *clh_head;
 143
 144 /**
 145  * Tail of the DLL.
 146  */
 147 static struct ClientLookupHandle *clh_tail;
 148
 149 /**
 150  * Useful for zone update for DHT put
 151  */
 152 static unsigned long long num_public_records;
 153
 154 /**
 155  * Last seen record count
 156  */
 157 static unsigned long long last_num_public_records;
 158
 159 /**
 160  * Minimum relative expiration time of records seem during the current
 161  * zone iteration.
 162  */
 163 static struct GNUNET_TIME_Relative min_relative_record_time;
 164
 165 /**
 166  * Zone iteration PUT interval.
 167  */
 168 static struct GNUNET_TIME_Relative put_interval;
 169
 170 /**
 171  * Time window for zone iteration
 172  */
 173 static struct GNUNET_TIME_Relative zone_publish_time_window;
 174
 175 /**
 176  * zone publish task
 177  */
 178 static GNUNET_SCHEDULER_TaskIdentifier zone_publish_task;
 179
 180 /**
 181  * #GNUNET_YES if zone has never been published before
 182  */
 183 static int first_zone_iteration;
 184
 185 /**
 186  * #GNUNET_YES if ipv6 is supported
 187  */
 188 static int v6_enabled;
 189
 190 /**
 191  * #GNUNET_YES if ipv4 is supported
 192  */
 193 static int v4_enabled;
 194
 195 /**
 196  * Handle to the statistics service
 197  */
 198 static struct GNUNET_STATISTICS_Handle *statistics;
 199
 200
 201 /**
 202  * Task run during shutdown.
 203  *
 204  * @param cls unused
 205  * @param tc unused
 206  */
 207 static void
 208 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 209 {
 210   struct ClientLookupHandle *clh;
 211
 212   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 213               "Shutting down!\n");
 214   GNUNET_SERVER_notification_context_destroy (nc);
 215   while (NULL != (clh = clh_head))
 216   {
 217     GNUNET_SERVER_client_set_user_context (clh->client, NULL);
 218     GNS_resolver_lookup_cancel (clh->lookup);
 219     GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
 220     GNUNET_free (clh);
 221   }
 222
 223   GNS_interceptor_done ();
 224   GNS_resolver_done ();
 225   GNS_shorten_done ();
 226   if (NULL != statistics)
 227   {
 228     GNUNET_STATISTICS_destroy (statistics, GNUNET_NO);
 229     statistics = NULL;
 230   }
 231   if (GNUNET_SCHEDULER_NO_TASK != zone_publish_task)
 232   {
 233     GNUNET_SCHEDULER_cancel (zone_publish_task);
 234     zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
 235   }
 236   if (NULL != namestore_iter)
 237   {
 238     GNUNET_NAMESTORE_zone_iteration_stop (namestore_iter);
 239     namestore_iter = NULL;
 240   }
 241   if (NULL != namestore_handle)
 242   {
 243     GNUNET_NAMESTORE_disconnect (namestore_handle);
 244     namestore_handle = NULL;
 245   }
 246   if (NULL != namecache_handle)
 247   {
 248     GNUNET_NAMECACHE_disconnect (namecache_handle);
 249     namecache_handle = NULL;
 250   }
 251   if (NULL != active_put)
 252   {
 253     GNUNET_DHT_put_cancel (active_put);
 254     active_put = NULL;
 255   }
 256   if (NULL != dht_handle)
 257   {
 258     GNUNET_DHT_disconnect (dht_handle);
 259     dht_handle = NULL;
 260   }
 261 }
 262
 263
 264 /**
 265  * Method called periodically that triggers iteration over authoritative records
 266  *
 267  * @param cls closure
 268  * @param tc task context
 269  */
 270 static void
 271 publish_zone_dht_next (void *cls,
 272                        const struct GNUNET_SCHEDULER_TaskContext *tc)
 273 {
 274   zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
 275   GNUNET_NAMESTORE_zone_iterator_next (namestore_iter);
 276 }
 277
 278
 279 /**
 280  * Periodically iterate over our zone and store everything in dht
 281  *
 282  * @param cls NULL
 283  * @param tc task context
 284  */
 285 static void
 286 publish_zone_dht_start (void *cls,
 287                         const struct GNUNET_SCHEDULER_TaskContext *tc);
 288
 289
 290 /**
 291  * Continuation called from DHT once the PUT operation is done.
 292  *
 293  * @param cls closure, NULL
 294  * @param success #GNUNET_OK on success
 295  */
 296 static void
 297 dht_put_continuation (void *cls,
 298                       int success)
 299 {
 300   struct GNUNET_TIME_Relative next_put_interval;
 301
 302   active_put = NULL;
 303   num_public_records++;
 304   if ( (num_public_records > last_num_public_records) &&
 305        (GNUNET_NO == first_zone_iteration) )
 306   {
 307     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 308                 "Last record count was lower than current record count.  Reducing interval.\n");
 309     put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
 310                                                 num_public_records);
 311     next_put_interval = GNUNET_TIME_relative_divide (put_interval,
 312                                                      LATE_ITERATION_SPEEDUP_FACTOR);
 313   }
 314   else
 315     next_put_interval = put_interval;
 316
 317   GNUNET_STATISTICS_set (statistics,
 318                          "Current zone iteration interval (ms)",
 319                          next_put_interval.rel_value_us / 1000LL,
 320                          GNUNET_NO);
 321   zone_publish_task = GNUNET_SCHEDULER_add_delayed (next_put_interval,
 322                                                     &publish_zone_dht_next,
 323                                                     NULL);
 324 }
 325
 326
 327 /**
 328  * Function used to put all records successively into the DHT.
 329  *
 330  * @param cls the closure (NULL)
 331  * @param key the private key of the authority (ours)
 332  * @param name the name of the records, NULL once the iteration is done
 333  * @param rd_count the number of records in @a rd
 334  * @param rd the record data
 335  */
 336 static void
 337 put_gns_record (void *cls,
 338                 const struct GNUNET_CRYPTO_EcdsaPrivateKey *key,
 339                 const char *name,
 340                 unsigned int rd_count,
 341                 const struct GNUNET_GNSRECORD_Data *rd)
 342 {
 343   struct GNUNET_GNSRECORD_Block *block;
 344   struct GNUNET_HashCode query;
 345   struct GNUNET_TIME_Absolute expire;
 346   struct GNUNET_TIME_Absolute now;
 347   size_t block_size;
 348   struct GNUNET_GNSRECORD_Data rd_public[rd_count];
 349   unsigned int rd_public_count;
 350   unsigned int i;
 351
 352   if (NULL == name)
 353   {
 354     /* we're done with one iteration, calculate when to do the next one */
 355     namestore_iter = NULL;
 356     last_num_public_records = num_public_records;
 357     first_zone_iteration = GNUNET_NO;
 358     if (0 == num_public_records)
 359     {
 360       /**
 361        * If no records are known (startup) or none present
 362        * we can safely set the interval to the value for a single
 363        * record
 364        */
 365       put_interval = zone_publish_time_window;
 366       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
 367                   "No records in namestore database.\n");
 368     }
 369     else
 370     {
 371       zone_publish_time_window
 372         = GNUNET_TIME_relative_min (min_relative_record_time,
 373                                     DEFAULT_ZONE_PUBLISH_TIME_WINDOW);
 374       put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
 375                                                   num_public_records);
 376     }
 377     /* reset for next iteration */
 378     min_relative_record_time = GNUNET_TIME_UNIT_FOREVER_REL;
 379     put_interval = GNUNET_TIME_relative_max (MINIMUM_ZONE_ITERATION_INTERVAL,
 380                                              put_interval);
 381
 382     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 383                 "Zone iteration finished. Adjusted zone iteration interval to %s\n",
 384                 GNUNET_STRINGS_relative_time_to_string (put_interval, GNUNET_YES));
 385     GNUNET_STATISTICS_set (statistics,
 386                            "Current zone iteration interval (in ms)",
 387                            put_interval.rel_value_us / 1000LL,
 388                            GNUNET_NO);
 389     GNUNET_STATISTICS_update (statistics,
 390                               "Number of zone iterations",
 391                               1,
 392                               GNUNET_NO);
 393     GNUNET_STATISTICS_set (statistics,
 394                            "Number of public records in DHT",
 395                            last_num_public_records,
 396                            GNUNET_NO);
 397     if (0 == num_public_records)
 398       zone_publish_task = GNUNET_SCHEDULER_add_delayed (put_interval,
 399                                                         &publish_zone_dht_start,
 400                                                         NULL);
 401     else
 402       zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
 403                                                     NULL);
 404     return;
 405   }
 406
 407   /* filter out records that are not public, and convert to
 408      absolute expiration time. */
 409   rd_public_count = 0;
 410   now = GNUNET_TIME_absolute_get ();
 411   for (i=0;i<rd_count;i++)
 412     if (0 == (rd[i].flags & (GNUNET_GNSRECORD_RF_PRIVATE |
 413                              GNUNET_GNSRECORD_RF_PENDING)))
 414     {
 415       rd_public[rd_public_count] = rd[i];
 416       if (0 != (rd[i].flags & GNUNET_GNSRECORD_RF_RELATIVE_EXPIRATION))
 417       {
 418         /* GNUNET_GNSRECORD_block_create will convert to absolute time;
 419            we just need to adjust our iteration frequency */
 420         min_relative_record_time.rel_value_us =
 421           GNUNET_MIN (rd_public[rd_public_count].expiration_time,
 422                       min_relative_record_time.rel_value_us);
 423       }
 424       else if (rd_public[rd_public_count].expiration_time < now.abs_value_us)
 425       {
 426         /* record already expired, skip it */
 427         continue;
 428       }
 429       rd_public_count++;
 430     }
 431
 432   /* We got a set of records to publish */
 433   if (0 == rd_public_count)
 434   {
 435     zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_next,
 436                                                    NULL);
 437     return;
 438   }
 439   expire = GNUNET_GNSRECORD_record_get_expiration_time (rd_public_count,
 440                                                         rd_public);
 441   block = GNUNET_GNSRECORD_block_create (key,
 442                                          expire,
 443                                          name,
 444                                          rd_public,
 445                                          rd_public_count);
 446   block_size = ntohl (block->purpose.size)
 447     + sizeof (struct GNUNET_CRYPTO_EcdsaSignature)
 448     + sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey);
 449   GNUNET_GNSRECORD_query_from_private_key (key,
 450                                            name,
 451                                            &query);
 452   active_put = GNUNET_DHT_put (dht_handle, &query,
 453                                DHT_GNS_REPLICATION_LEVEL,
 454                                GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE,
 455                                GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
 456                                block_size,
 457                                block,
 458                                expire,
 459                                DHT_OPERATION_TIMEOUT,
 460                                &dht_put_continuation,
 461                                NULL);
 462   if (NULL == active_put)
 463   {
 464     GNUNET_break (0);
 465     dht_put_continuation (NULL, GNUNET_NO);
 466   }
 467   GNUNET_free (block);
 468 }
 469
 470
 471 /**
 472  * Periodically iterate over our zone and store everything in dht
 473  *
 474  * @param cls NULL
 475  * @param tc task context
 476  */
 477 static void
 478 publish_zone_dht_start (void *cls,
 479                         const struct GNUNET_SCHEDULER_TaskContext *tc)
 480 {
 481   zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
 482
 483   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 484               "Starting DHT zone update!\n");
 485   /* start counting again */
 486   num_public_records = 0;
 487   namestore_iter = GNUNET_NAMESTORE_zone_iteration_start (namestore_handle,
 488                                                           NULL, /* All zones */
 489                                                           &put_gns_record,
 490                                                           NULL);
 491 }
 492
 493
 494 /* END DHT ZONE PROPAGATION */
 495
 496
 497 /**
 498  * Reply to client with the result from our lookup.
 499  *
 500  * @param cls the closure (our client lookup handle)
 501  * @param rd_count the number of records in @a rd
 502  * @param rd the record data
 503  */
 504 static void
 505 send_lookup_response (void* cls,
 506                       uint32_t rd_count,
 507                       const struct GNUNET_GNSRECORD_Data *rd)
 508 {
 509   struct ClientLookupHandle *clh = cls;
 510   struct GNUNET_GNS_ClientLookupResultMessage *rmsg;
 511   size_t len;
 512
 513   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 514               "Sending `%s' message with %d results\n",
 515               "LOOKUP_RESULT",
 516               rd_count);
 517
 518   len = GNUNET_GNSRECORD_records_get_size (rd_count, rd);
 519   rmsg = GNUNET_malloc (len + sizeof (struct GNUNET_GNS_ClientLookupResultMessage));
 520   rmsg->header.type = htons (GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT);
 521   rmsg->header.size = htons (len + sizeof(struct GNUNET_GNS_ClientLookupResultMessage));
 522   rmsg->id = clh->request_id;
 523   rmsg->rd_count = htonl (rd_count);
 524   GNUNET_GNSRECORD_records_serialize (rd_count, rd, len,
 525                                       (char*) &rmsg[1]);
 526   GNUNET_SERVER_notification_context_unicast (nc,
 527                                               clh->client,
 528                                               &rmsg->header,
 529                                               GNUNET_NO);
 530   GNUNET_free (rmsg);
 531   GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
 532   GNUNET_SERVER_client_set_user_context (clh->client, NULL);
 533   GNUNET_free (clh);
 534   GNUNET_STATISTICS_update (statistics,
 535                             "Completed lookups", 1,
 536                             GNUNET_NO);
 537   GNUNET_STATISTICS_update (statistics,
 538                             "Records resolved",
 539                             rd_count,
 540                             GNUNET_NO);
 541 }
 542
 543
 544 /**
 545  * Handle lookup requests from client
 546  *
 547  * @param cls the closure
 548  * @param client the client
 549  * @param message the message
 550  */
 551 static void
 552 handle_lookup (void *cls,
 553                struct GNUNET_SERVER_Client *client,
 554                const struct GNUNET_MessageHeader *message)
 555 {
 556   char name[GNUNET_DNSPARSER_MAX_NAME_LENGTH + 1];
 557   struct ClientLookupHandle *clh;
 558   char *nameptr = name;
 559   const char *utf_in;
 560   const struct GNUNET_CRYPTO_EcdsaPrivateKey *key;
 561   uint16_t msg_size;
 562   const struct GNUNET_GNS_ClientLookupMessage *sh_msg;
 563
 564   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 565               "Received `%s' message\n",
 566               "LOOKUP");
 567   msg_size = ntohs (message->size);
 568   if (msg_size < sizeof (struct GNUNET_GNS_ClientLookupMessage))
 569   {
 570     GNUNET_break (0);
 571     GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
 572     return;
 573   }
 574   sh_msg = (const struct GNUNET_GNS_ClientLookupMessage *) message;
 575   GNUNET_SERVER_notification_context_add (nc, client);
 576   if (GNUNET_YES == ntohs (sh_msg->have_key))
 577     key = &sh_msg->shorten_key;
 578   else
 579     key = NULL;
 580   utf_in = (const char *) &sh_msg[1];
 581   if ( ('\0' != utf_in[msg_size - sizeof (struct GNUNET_GNS_ClientLookupMessage) - 1]) ||
 582        (strlen (utf_in) > GNUNET_DNSPARSER_MAX_NAME_LENGTH) )
 583   {
 584     GNUNET_break (0);
 585     GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
 586     return;
 587   }
 588   GNUNET_STRINGS_utf8_tolower (utf_in, &nameptr);
 589   GNUNET_SERVER_receive_done (client, GNUNET_OK);
 590
 591   clh = GNUNET_new (struct ClientLookupHandle);
 592   GNUNET_SERVER_client_set_user_context (client, clh);
 593   GNUNET_CONTAINER_DLL_insert (clh_head, clh_tail, clh);
 594   clh->client = client;
 595   clh->request_id = sh_msg->id;
 596   if ( (GNUNET_DNSPARSER_TYPE_A == ntohl (sh_msg->type)) &&
 597        (GNUNET_OK != v4_enabled) )
 598   {
 599     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 600                 "LOOKUP: Query for A record but AF_INET not supported!");
 601     send_lookup_response (clh, 0, NULL);
 602     return;
 603   }
 604   if ( (GNUNET_DNSPARSER_TYPE_AAAA == ntohl (sh_msg->type)) &&
 605        (GNUNET_OK != v6_enabled) )
 606   {
 607     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 608                 "LOOKUP: Query for AAAA record but AF_INET6 not supported!");
 609     send_lookup_response (clh, 0, NULL);
 610     return;
 611   }
 612   clh->lookup = GNS_resolver_lookup (&sh_msg->zone,
 613                                      ntohl (sh_msg->type),
 614                                      name,
 615                                      key,
 616                                      ntohl (sh_msg->only_cached),
 617                                      &send_lookup_response, clh);
 618   GNUNET_STATISTICS_update (statistics,
 619                             "Lookup attempts",
 620                             1, GNUNET_NO);
 621 }
 622
 623
 624 /**
 625  * One of our clients disconnected, clean up after it.
 626  *
 627  * @param cls NULL
 628  * @param client the client that disconnected
 629  */
 630 static void
 631 notify_client_disconnect (void *cls,
 632                           struct GNUNET_SERVER_Client *client)
 633 {
 634   struct ClientLookupHandle *clh;
 635
 636   if (NULL == client)
 637     return;
 638   clh = GNUNET_SERVER_client_get_user_context (client, struct ClientLookupHandle);
 639   if (NULL == clh)
 640     return;
 641   GNS_resolver_lookup_cancel (clh->lookup);
 642   GNUNET_CONTAINER_DLL_remove (clh_head, clh_tail, clh);
 643   GNUNET_free (clh);
 644 }
 645
 646
 647 /**
 648  * Process GNS requests.
 649  *
 650  * @param cls closure
 651  * @param server the initialized server
 652  * @param c configuration to use
 653  */
 654 static void
 655 run (void *cls, struct GNUNET_SERVER_Handle *server,
 656      const struct GNUNET_CONFIGURATION_Handle *c)
 657 {
 658   static const struct GNUNET_SERVER_MessageHandler handlers[] = {
 659     { &handle_lookup, NULL, GNUNET_MESSAGE_TYPE_GNS_LOOKUP, 0},
 660     {NULL, NULL, 0, 0}
 661   };
 662   struct GNUNET_CRYPTO_EcdsaPublicKey dns_root;
 663   unsigned long long max_parallel_bg_queries = 0;
 664   char *dns_root_name;
 665
 666   v6_enabled = GNUNET_NETWORK_test_pf (PF_INET6);
 667   v4_enabled = GNUNET_NETWORK_test_pf (PF_INET);
 668   min_relative_record_time = GNUNET_TIME_UNIT_FOREVER_REL;
 669   namestore_handle = GNUNET_NAMESTORE_connect (c);
 670   if (NULL == namestore_handle)
 671   {
 672     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 673                 _("Failed to connect to the namestore!\n"));
 674     GNUNET_SCHEDULER_shutdown ();
 675     return;
 676   }
 677   namecache_handle = GNUNET_NAMECACHE_connect (c);
 678   if (NULL == namecache_handle)
 679   {
 680     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 681                 _("Failed to connect to the namecache!\n"));
 682     GNUNET_SCHEDULER_shutdown ();
 683     return;
 684   }
 685
 686   put_interval = INITIAL_PUT_INTERVAL;
 687   zone_publish_time_window = DEFAULT_ZONE_PUBLISH_TIME_WINDOW;
 688
 689   if (GNUNET_OK ==
 690       GNUNET_CONFIGURATION_get_value_time (c, "gns",
 691                                            "ZONE_PUBLISH_TIME_WINDOW",
 692                                            &zone_publish_time_window))
 693   {
 694     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 695                 "Time window for zone iteration: %s\n",
 696                 GNUNET_STRINGS_relative_time_to_string (zone_publish_time_window, GNUNET_YES));
 697   }
 698   if (GNUNET_OK ==
 699       GNUNET_CONFIGURATION_get_value_number (c, "gns",
 700                                             "MAX_PARALLEL_BACKGROUND_QUERIES",
 701                                             &max_parallel_bg_queries))
 702   {
 703     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 704                 "Number of allowed parallel background queries: %llu\n",
 705                 max_parallel_bg_queries);
 706   }
 707
 708   dht_handle = GNUNET_DHT_connect (c,
 709                                    (unsigned int) max_parallel_bg_queries);
 710   if (NULL == dht_handle)
 711   {
 712     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
 713                 _("Could not connect to DHT!\n"));
 714     GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
 715     return;
 716   }
 717
 718   if (GNUNET_OK ==
 719       GNUNET_CONFIGURATION_get_value_string (c, "gns", "DNS_ROOT",
 720                                              &dns_root_name))
 721   {
 722     if (GNUNET_OK !=
 723         GNUNET_CRYPTO_ecdsa_public_key_from_string (dns_root_name,
 724                                                   strlen (dns_root_name),
 725                                                   &dns_root))
 726     {
 727       GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
 728                                  "gns", "DNS_ROOT",
 729                                  _("valid public key required"));
 730       GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
 731       GNUNET_free (dns_root_name);
 732       return;
 733     }
 734     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
 735                 "DNS hijacking with root `%s' enabled. Connecting to DNS service.\n",
 736                 dns_root_name);
 737     GNUNET_free (dns_root_name);
 738     if (GNUNET_SYSERR ==
 739         GNS_interceptor_init (&dns_root, c))
 740     {
 741       GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
 742       return;
 743     }
 744   }
 745   GNS_resolver_init (namestore_handle,
 746                      namecache_handle,
 747                      dht_handle,
 748                      c,
 749                      max_parallel_bg_queries);
 750   GNS_shorten_init (namestore_handle,
 751                     namecache_handle,
 752                     dht_handle);
 753   GNUNET_SERVER_disconnect_notify (server,
 754                                    &notify_client_disconnect,
 755                                    NULL);
 756   /* Schedule periodic put for our records. */
 757   first_zone_iteration = GNUNET_YES;
 758   GNUNET_SERVER_add_handlers (server, handlers);
 759   statistics = GNUNET_STATISTICS_create ("gns", c);
 760   nc = GNUNET_SERVER_notification_context_create (server, 1);
 761   zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
 762                                                 NULL);
 763   GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
 764                                 &shutdown_task, NULL);
 765 }
 766
 767
 768 /**
 769  * The main function for the GNS service.
 770  *
 771  * @param argc number of arguments from the command line
 772  * @param argv command line arguments
 773  * @return 0 ok, 1 on error
 774  */
 775 int
 776 main (int argc, char *const *argv)
 777 {
 778   int ret;
 779
 780   ret =
 781       (GNUNET_OK ==
 782        GNUNET_SERVICE_run (argc, argv, "gns", GNUNET_SERVICE_OPTION_NONE, &run,
 783                            NULL)) ? 0 : 1;
 784   return ret;
 785 }
 786
 787 /* end of gnunet-service-gns.c */