src/gns/gnunet-service-gns.c

   1 /*
   2      This file is part of GNUnet.
   3      Copyright (C) 2011-2013 GNUnet e.V.
   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., 51 Franklin Street, Fifth Floor,
  18      Boston, MA 02110-1301, 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_identity_service.h"
  34 #include "gnunet_gns_service.h"
  35 #include "gnunet_statistics_service.h"
  36 #include "gns.h"
  37 #include "gnunet-service-gns_resolver.h"
  38 #include "gnunet-service-gns_reverser.h"
  39 #include "gnunet-service-gns_shorten.h"
  40 #include "gnunet-service-gns_interceptor.h"
  41 #include "gnunet_protocols.h"
  42
  43 /**
  44  * The initial interval in milliseconds btween puts in
  45  * a zone iteration
  46  */
  47 #define INITIAL_PUT_INTERVAL GNUNET_TIME_UNIT_MILLISECONDS
  48
  49 /**
  50  * The lower bound for the zone iteration interval
  51  */
  52 #define MINIMUM_ZONE_ITERATION_INTERVAL GNUNET_TIME_UNIT_SECONDS
  53
  54 /**
  55  * The upper bound for the zone iteration interval
  56  */
  57 #define MAXIMUM_ZONE_ITERATION_INTERVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 15)
  58
  59 /**
  60  * The default put interval for the zone iteration. In case
  61  * no option is found
  62  */
  63 #define DEFAULT_ZONE_PUBLISH_TIME_WINDOW GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 4)
  64
  65 /**
  66  * The factor the current zone iteration interval is divided by for each
  67  * additional new record
  68  */
  69 #define LATE_ITERATION_SPEEDUP_FACTOR 2
  70
  71 /**
  72  * How long until a DHT PUT attempt should time out?
  73  */
  74 #define DHT_OPERATION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 60)
  75
  76 /**
  77  * What replication level do we use for DHT PUT operations?
  78  */
  79 #define DHT_GNS_REPLICATION_LEVEL 5
  80
  81 /**
  82  * GnsClient prototype
  83  */
  84 struct GnsClient;
  85
  86 /**
  87  * Handle to a lookup operation from api
  88  */
  89 struct ClientLookupHandle
  90 {
  91
  92   /**
  93    * We keep these in a DLL.
  94    */
  95   struct ClientLookupHandle *next;
  96
  97   /**
  98    * We keep these in a DLL.
  99    */
 100   struct ClientLookupHandle *prev;
 101
 102   /**
 103    * Client handle
 104    */
 105   struct GnsClient *gc;
 106
 107   /**
 108    * Active handle for the lookup.
 109    */
 110   struct GNS_ResolverHandle *lookup;
 111
 112   /**
 113    * Active handle for a reverse lookup
 114    */
 115   struct GNS_ReverserHandle *rev_lookup;
 116
 117   /**
 118    * request id
 119    */
 120   uint32_t request_id;
 121
 122 };
 123
 124 struct GnsClient
 125 {
 126   /**
 127    * The client
 128    */
 129   struct GNUNET_SERVICE_Client *client;
 130
 131   /**
 132    * The MQ
 133    */
 134   struct GNUNET_MQ_Handle *mq;
 135
 136   /**
 137    * Head of the DLL.
 138    */
 139   struct ClientLookupHandle *clh_head;
 140
 141   /**
 142    * Tail of the DLL.
 143    */
 144   struct ClientLookupHandle *clh_tail;
 145 };
 146
 147
 148 /**
 149  * Handle for DHT PUT activity triggered from the namestore monitor.
 150  */
 151 struct MonitorActivity
 152 {
 153   /**
 154    * Kept in a DLL.
 155    */
 156   struct MonitorActivity *next;
 157
 158   /**
 159    * Kept in a DLL.
 160    */
 161   struct MonitorActivity *prev;
 162
 163   /**
 164    * Handle for the DHT PUT operation.
 165    */
 166   struct GNUNET_DHT_PutHandle *ph;
 167 };
 168
 169
 170 /**
 171  * Our handle to the DHT
 172  */
 173 static struct GNUNET_DHT_Handle *dht_handle;
 174
 175 /**
 176  * Active DHT put operation (or NULL)
 177  */
 178 static struct GNUNET_DHT_PutHandle *active_put;
 179
 180 /**
 181  * Our handle to the namestore service
 182  */
 183 static struct GNUNET_NAMESTORE_Handle *namestore_handle;
 184
 185 /**
 186  * Our handle to the namecache service
 187  */
 188 static struct GNUNET_NAMECACHE_Handle *namecache_handle;
 189
 190 /**
 191  * Our handle to the identity service
 192  */
 193 static struct GNUNET_IDENTITY_Handle *identity_handle;
 194
 195 /**
 196  * Our handle to the identity operation to find the master zone
 197  * for intercepted queries.
 198  */
 199 static struct GNUNET_IDENTITY_Operation *identity_op;
 200
 201 /**
 202  * Handle to iterate over our authoritative zone in namestore
 203  */
 204 static struct GNUNET_NAMESTORE_ZoneIterator *namestore_iter;
 205
 206 /**
 207  * Handle to monitor namestore changes to instant propagation.
 208  */
 209 static struct GNUNET_NAMESTORE_ZoneMonitor *zmon;
 210
 211 /**
 212  * Head of monitor activities; kept in a DLL.
 213  */
 214 static struct MonitorActivity *ma_head;
 215
 216 /**
 217  * Tail of monitor activities; kept in a DLL.
 218  */
 219 static struct MonitorActivity *ma_tail;
 220
 221 /**
 222  * Useful for zone update for DHT put
 223  */
 224 static unsigned long long num_public_records;
 225
 226 /**
 227  * Last seen record count
 228  */
 229 static unsigned long long last_num_public_records;
 230
 231 /**
 232  * Minimum relative expiration time of records seem during the current
 233  * zone iteration.
 234  */
 235 static struct GNUNET_TIME_Relative min_relative_record_time;
 236
 237 /**
 238  * Zone iteration PUT interval.
 239  */
 240 static struct GNUNET_TIME_Relative put_interval;
 241
 242 /**
 243  * Default time window for zone iteration
 244  */
 245 static struct GNUNET_TIME_Relative zone_publish_time_window_default;
 246
 247 /**
 248  * Time window for zone iteration, adjusted based on relative record
 249  * expiration times in our zone.
 250  */
 251 static struct GNUNET_TIME_Relative zone_publish_time_window;
 252
 253 /**
 254  * zone publish task
 255  */
 256 static struct GNUNET_SCHEDULER_Task *zone_publish_task;
 257
 258 /**
 259  * #GNUNET_YES if zone has never been published before
 260  */
 261 static int first_zone_iteration;
 262
 263 /**
 264  * #GNUNET_YES if ipv6 is supported
 265  */
 266 static int v6_enabled;
 267
 268 /**
 269  * #GNUNET_YES if ipv4 is supported
 270  */
 271 static int v4_enabled;
 272
 273 /**
 274  * Handle to the statistics service
 275  */
 276 static struct GNUNET_STATISTICS_Handle *statistics;
 277
 278
 279 /**
 280  * Task run during shutdown.
 281  *
 282  * @param cls unused
 283  * @param tc unused
 284  */
 285 static void
 286 shutdown_task (void *cls)
 287 {
 288   struct MonitorActivity *ma;
 289
 290   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 291               "Shutting down!\n");
 292   GNS_interceptor_done ();
 293   if (NULL != identity_op)
 294   {
 295     GNUNET_IDENTITY_cancel (identity_op);
 296     identity_op = NULL;
 297   }
 298   if (NULL != identity_handle)
 299   {
 300     GNUNET_IDENTITY_disconnect (identity_handle);
 301     identity_handle = NULL;
 302   }
 303   GNS_resolver_done ();
 304   GNS_shorten_done ();
 305   while (NULL != (ma = ma_head))
 306   {
 307     GNUNET_DHT_put_cancel (ma->ph);
 308     GNUNET_CONTAINER_DLL_remove (ma_head,
 309                                  ma_tail,
 310                                  ma);
 311     GNUNET_free (ma);
 312   }
 313   if (NULL != statistics)
 314   {
 315     GNUNET_STATISTICS_destroy (statistics,
 316                                GNUNET_NO);
 317     statistics = NULL;
 318   }
 319   if (NULL != zone_publish_task)
 320   {
 321     GNUNET_SCHEDULER_cancel (zone_publish_task);
 322     zone_publish_task = NULL;
 323   }
 324   if (NULL != namestore_iter)
 325   {
 326     GNUNET_NAMESTORE_zone_iteration_stop (namestore_iter);
 327     namestore_iter = NULL;
 328   }
 329   if (NULL != zmon)
 330   {
 331     GNUNET_NAMESTORE_zone_monitor_stop (zmon);
 332     zmon = NULL;
 333   }
 334   if (NULL != namestore_handle)
 335   {
 336     GNUNET_NAMESTORE_disconnect (namestore_handle);
 337     namestore_handle = NULL;
 338   }
 339   if (NULL != namecache_handle)
 340   {
 341     GNUNET_NAMECACHE_disconnect (namecache_handle);
 342     namecache_handle = NULL;
 343   }
 344   if (NULL != active_put)
 345   {
 346     GNUNET_DHT_put_cancel (active_put);
 347     active_put = NULL;
 348   }
 349   if (NULL != dht_handle)
 350   {
 351     GNUNET_DHT_disconnect (dht_handle);
 352     dht_handle = NULL;
 353   }
 354 }
 355
 356 /**
 357  * Called whenever a client is disconnected.
 358  *
 359  * @param cls closure
 360  * @param client identification of the client
 361  * @param app_ctx @a client
 362  */
 363 static void
 364 client_disconnect_cb (void *cls,
 365                       struct GNUNET_SERVICE_Client *client,
 366                       void *app_ctx)
 367 {
 368   struct ClientLookupHandle *clh;
 369   struct GnsClient *gc = app_ctx;
 370
 371   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 372               "Client %p disconnected\n",
 373               client);
 374   while (NULL != (clh = gc->clh_head))
 375   {
 376     if (NULL != clh->lookup)
 377       GNS_resolver_lookup_cancel (clh->lookup);
 378     if (NULL != clh->rev_lookup)
 379       GNS_reverse_lookup_cancel (clh->rev_lookup);
 380     GNUNET_CONTAINER_DLL_remove (gc->clh_head,
 381                                  gc->clh_tail,
 382                                  clh);
 383     GNUNET_free (clh);
 384   }
 385
 386   GNUNET_free (gc);
 387 }
 388
 389
 390 /**
 391  * Add a client to our list of active clients.
 392  *
 393  * @param cls NULL
 394  * @param client client to add
 395  * @param mq message queue for @a client
 396  * @return internal namestore client structure for this client
 397  */
 398 static void *
 399 client_connect_cb (void *cls,
 400                    struct GNUNET_SERVICE_Client *client,
 401                    struct GNUNET_MQ_Handle *mq)
 402 {
 403   struct GnsClient *gc;
 404   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 405               "Client %p connected\n",
 406               client);
 407   gc = GNUNET_new (struct GnsClient);
 408   gc->client = client;
 409   gc->mq = mq;
 410   return gc;
 411 }
 412
 413
 414 /**
 415  * Method called periodically that triggers iteration over authoritative records
 416  *
 417  * @param cls closure
 418  */
 419 static void
 420 publish_zone_dht_next (void *cls)
 421 {
 422   zone_publish_task = NULL;
 423   GNUNET_assert (NULL != namestore_iter);
 424   GNUNET_NAMESTORE_zone_iterator_next (namestore_iter);
 425 }
 426
 427
 428 /**
 429  * Periodically iterate over our zone and store everything in dht
 430  *
 431  * @param cls NULL
 432  */
 433 static void
 434 publish_zone_dht_start (void *cls);
 435
 436
 437 /**
 438  * Continuation called from DHT once the PUT operation is done.
 439  *
 440  * @param cls closure, NULL if called from regular iteration,
 441  *        `struct MonitorActivity` if called from #handle_monitor_event.
 442  * @param success #GNUNET_OK on success
 443  */
 444 static void
 445 dht_put_continuation (void *cls,
 446                       int success)
 447 {
 448   struct MonitorActivity *ma = cls;
 449   struct GNUNET_TIME_Relative next_put_interval;
 450
 451   num_public_records++;
 452   if (NULL == ma)
 453   {
 454     active_put = NULL;
 455     if ( (num_public_records > last_num_public_records) &&
 456          (GNUNET_NO == first_zone_iteration) )
 457     {
 458       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 459                   "Last record count was lower than current record count.  Reducing interval.\n");
 460       put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
 461                                                   num_public_records);
 462       next_put_interval = GNUNET_TIME_relative_divide (put_interval,
 463                                                        LATE_ITERATION_SPEEDUP_FACTOR);
 464     }
 465     else
 466       next_put_interval = put_interval;
 467     next_put_interval = GNUNET_TIME_relative_min (next_put_interval,
 468                                                   MAXIMUM_ZONE_ITERATION_INTERVAL);
 469     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 470                 "PUT complete, next PUT in %s!\n",
 471                 GNUNET_STRINGS_relative_time_to_string (next_put_interval,
 472                                                         GNUNET_YES));
 473
 474     GNUNET_STATISTICS_set (statistics,
 475                            "Current zone iteration interval (ms)",
 476                            next_put_interval.rel_value_us / 1000LL,
 477                            GNUNET_NO);
 478     GNUNET_assert (NULL == zone_publish_task);
 479     zone_publish_task = GNUNET_SCHEDULER_add_delayed (next_put_interval,
 480                                                       &publish_zone_dht_next,
 481                                                       NULL);
 482   }
 483   else
 484   {
 485     GNUNET_CONTAINER_DLL_remove (ma_head,
 486                                  ma_tail,
 487                                  ma);
 488     GNUNET_free (ma);
 489   }
 490 }
 491
 492
 493 /**
 494  * Convert namestore records from the internal format to that
 495  * suitable for publication (removes private records, converts
 496  * to absolute expiration time).
 497  *
 498  * @param rd input records
 499  * @param rd_count size of the @a rd and @a rd_public arrays
 500  * @param rd_public where to write the converted records
 501  * @return number of records written to @a rd_public
 502  */
 503 static unsigned int
 504 convert_records_for_export (const struct GNUNET_GNSRECORD_Data *rd,
 505                             unsigned int rd_count,
 506                             struct GNUNET_GNSRECORD_Data *rd_public)
 507 {
 508   struct GNUNET_TIME_Absolute now;
 509   unsigned int rd_public_count;
 510   unsigned int i;
 511
 512   rd_public_count = 0;
 513   now = GNUNET_TIME_absolute_get ();
 514   for (i=0;i<rd_count;i++)
 515     if (0 == (rd[i].flags & GNUNET_GNSRECORD_RF_PRIVATE))
 516     {
 517       rd_public[rd_public_count] = rd[i];
 518       if (0 != (rd[i].flags & GNUNET_GNSRECORD_RF_RELATIVE_EXPIRATION))
 519       {
 520         /* GNUNET_GNSRECORD_block_create will convert to absolute time;
 521            we just need to adjust our iteration frequency */
 522         min_relative_record_time.rel_value_us =
 523           GNUNET_MIN (rd_public[rd_public_count].expiration_time,
 524                       min_relative_record_time.rel_value_us);
 525       }
 526       else if (rd_public[rd_public_count].expiration_time < now.abs_value_us)
 527       {
 528         /* record already expired, skip it */
 529         continue;
 530       }
 531       rd_public_count++;
 532     }
 533   return rd_public_count;
 534 }
 535
 536
 537 /**
 538  * Store GNS records in the DHT.
 539  *
 540  * @param key key of the zone
 541  * @param label label to store under
 542  * @param rd_public public record data
 543  * @param rd_public_count number of records in @a rd_public
 544  * @param pc_arg closure argument to pass to the #dht_put_continuation
 545  * @return DHT PUT handle, NULL on error
 546  */
 547 static struct GNUNET_DHT_PutHandle *
 548 perform_dht_put (const struct GNUNET_CRYPTO_EcdsaPrivateKey *key,
 549                  const char *label,
 550                  const struct GNUNET_GNSRECORD_Data *rd_public,
 551                  unsigned int rd_public_count,
 552                  void *pc_arg)
 553 {
 554   struct GNUNET_GNSRECORD_Block *block;
 555   struct GNUNET_HashCode query;
 556   struct GNUNET_TIME_Absolute expire;
 557   size_t block_size;
 558   struct GNUNET_DHT_PutHandle *ret;
 559
 560   expire = GNUNET_GNSRECORD_record_get_expiration_time (rd_public_count,
 561                                                         rd_public);
 562   block = GNUNET_GNSRECORD_block_create (key,
 563                                          expire,
 564                                          label,
 565                                          rd_public,
 566                                          rd_public_count);
 567   if (NULL == block)
 568     return NULL; /* whoops */
 569   block_size = ntohl (block->purpose.size)
 570     + sizeof (struct GNUNET_CRYPTO_EcdsaSignature)
 571     + sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey);
 572   GNUNET_GNSRECORD_query_from_private_key (key,
 573                                            label,
 574                                            &query);
 575   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 576               "Storing %u record(s) for label `%s' in DHT with expiration `%s' under key %s\n",
 577               rd_public_count,
 578               label,
 579               GNUNET_STRINGS_absolute_time_to_string (expire),
 580               GNUNET_h2s (&query));
 581   ret = GNUNET_DHT_put (dht_handle,
 582                         &query,
 583                         DHT_GNS_REPLICATION_LEVEL,
 584                         GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE,
 585                         GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
 586                         block_size,
 587                         block,
 588                         expire,
 589                         &dht_put_continuation,
 590                         pc_arg);
 591   GNUNET_free (block);
 592   return ret;
 593 }
 594
 595
 596 /**
 597  * We encountered an error in our zone iteration.
 598  */
 599 static void
 600 zone_iteration_error (void *cls)
 601 {
 602   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 603               "Got disconnected from namestore database, retrying.\n");
 604   namestore_iter = NULL;
 605   /* We end up here on error/disconnect/shutdown, so potentially
 606      while a zone publish task or a DHT put is still running; hence
 607      we need to cancel those. */
 608   if (NULL != zone_publish_task)
 609   {
 610     GNUNET_SCHEDULER_cancel (zone_publish_task);
 611     zone_publish_task = NULL;
 612   }
 613   if (NULL != active_put)
 614   {
 615     GNUNET_DHT_put_cancel (active_put);
 616     active_put = NULL;
 617   }
 618   zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
 619                                                 NULL);
 620 }
 621
 622
 623 /**
 624  * Zone iteration is completed.
 625  */
 626 static void
 627 zone_iteration_finished (void *cls)
 628 {
 629   /* we're done with one iteration, calculate when to do the next one */
 630   namestore_iter = NULL;
 631   last_num_public_records = num_public_records;
 632   first_zone_iteration = GNUNET_NO;
 633   if (0 == num_public_records)
 634   {
 635     /**
 636      * If no records are known (startup) or none present
 637      * we can safely set the interval to the value for a single
 638      * record
 639      */
 640     put_interval = zone_publish_time_window;
 641     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
 642                 "No records in namestore database.\n");
 643   }
 644   else
 645   {
 646     /* If records are present, next publication is based on the minimum
 647      * relative expiration time of the records published divided by 4
 648      */
 649     zone_publish_time_window
 650       = GNUNET_TIME_relative_min (GNUNET_TIME_relative_divide (min_relative_record_time, 4),
 651                                   zone_publish_time_window_default);
 652     put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
 653                                                 num_public_records);
 654   }
 655   /* reset for next iteration */
 656   min_relative_record_time = GNUNET_TIME_UNIT_FOREVER_REL;
 657   put_interval = GNUNET_TIME_relative_max (MINIMUM_ZONE_ITERATION_INTERVAL,
 658                                            put_interval);
 659   put_interval = GNUNET_TIME_relative_min (put_interval,
 660                                            MAXIMUM_ZONE_ITERATION_INTERVAL);
 661   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 662               "Zone iteration finished. Adjusted zone iteration interval to %s\n",
 663               GNUNET_STRINGS_relative_time_to_string (put_interval,
 664                                                       GNUNET_YES));
 665   GNUNET_STATISTICS_set (statistics,
 666                          "Current zone iteration interval (in ms)",
 667                          put_interval.rel_value_us / 1000LL,
 668                          GNUNET_NO);
 669   GNUNET_STATISTICS_update (statistics,
 670                             "Number of zone iterations",
 671                             1,
 672                             GNUNET_NO);
 673   GNUNET_STATISTICS_set (statistics,
 674                          "Number of public records in DHT",
 675                          last_num_public_records,
 676                          GNUNET_NO);
 677   GNUNET_assert (NULL == zone_publish_task);
 678   if (0 == num_public_records)
 679     zone_publish_task = GNUNET_SCHEDULER_add_delayed (put_interval,
 680                                                       &publish_zone_dht_start,
 681                                                       NULL);
 682   else
 683     zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
 684                                                   NULL);
 685 }
 686
 687
 688 /**
 689  * Function used to put all records successively into the DHT.
 690  *
 691  * @param cls the closure (NULL)
 692  * @param key the private key of the authority (ours)
 693  * @param label the name of the records, NULL once the iteration is done
 694  * @param rd_count the number of records in @a rd
 695  * @param rd the record data
 696  */
 697 static void
 698 put_gns_record (void *cls,
 699                 const struct GNUNET_CRYPTO_EcdsaPrivateKey *key,
 700                 const char *label,
 701                 unsigned int rd_count,
 702                 const struct GNUNET_GNSRECORD_Data *rd)
 703 {
 704   struct GNUNET_GNSRECORD_Data rd_public[rd_count];
 705   unsigned int rd_public_count;
 706
 707   rd_public_count = convert_records_for_export (rd,
 708                                                 rd_count,
 709                                                 rd_public);
 710
 711   if (0 == rd_public_count)
 712   {
 713     GNUNET_assert (NULL == zone_publish_task);
 714     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 715                 "Record set empty, moving to next record set\n");
 716     zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_next,
 717                                                   NULL);
 718     return;
 719   }
 720   /* We got a set of records to publish */
 721   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 722               "Starting DHT PUT\n");
 723   active_put = perform_dht_put (key,
 724                                 label,
 725                                 rd_public,
 726                                 rd_public_count,
 727                                 NULL);
 728   if (NULL == active_put)
 729   {
 730     GNUNET_break (0);
 731     dht_put_continuation (NULL, GNUNET_NO);
 732   }
 733 }
 734
 735
 736 /**
 737  * Periodically iterate over all zones and store everything in DHT
 738  *
 739  * @param cls NULL
 740  */
 741 static void
 742 publish_zone_dht_start (void *cls)
 743 {
 744   zone_publish_task = NULL;
 745
 746   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 747               "Starting DHT zone update!\n");
 748   /* start counting again */
 749   num_public_records = 0;
 750   GNUNET_assert (NULL == namestore_iter);
 751   namestore_iter
 752     = GNUNET_NAMESTORE_zone_iteration_start (namestore_handle,
 753                                              NULL, /* All zones */
 754                                              &zone_iteration_error,
 755                                              NULL,
 756                                              &put_gns_record,
 757                                              NULL,
 758                                              &zone_iteration_finished,
 759                                              NULL);
 760 }
 761
 762
 763 /**
 764  * Process a record that was stored in the namestore
 765  * (invoked by the monitor).
 766  *
 767  * @param cls closure, NULL
 768  * @param zone private key of the zone; NULL on disconnect
 769  * @param label label of the records; NULL on disconnect
 770  * @param rd_count number of entries in @a rd array, 0 if label was deleted
 771  * @param rd array of records with data to store
 772  */
 773 static void
 774 handle_monitor_event (void *cls,
 775                       const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone,
 776                       const char *label,
 777                       unsigned int rd_count,
 778                       const struct GNUNET_GNSRECORD_Data *rd)
 779 {
 780   struct GNUNET_GNSRECORD_Data rd_public[rd_count];
 781   unsigned int rd_public_count;
 782   struct MonitorActivity *ma;
 783
 784   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 785               "Received %u records for label `%s' via namestore monitor\n",
 786               rd_count,
 787               label);
 788   /* filter out records that are not public, and convert to
 789      absolute expiration time. */
 790   rd_public_count = convert_records_for_export (rd,
 791                                                 rd_count,
 792                                                 rd_public);
 793   if (0 == rd_public_count)
 794     return; /* nothing to do */
 795   ma = GNUNET_new (struct MonitorActivity);
 796   ma->ph = perform_dht_put (zone,
 797                             label,
 798                             rd,
 799                             rd_count,
 800                             ma);
 801   if (NULL == ma->ph)
 802   {
 803     /* PUT failed, do not remember operation */
 804     GNUNET_free (ma);
 805     return;
 806   }
 807   GNUNET_CONTAINER_DLL_insert (ma_head,
 808                                ma_tail,
 809                                ma);
 810 }
 811
 812
 813 /* END DHT ZONE PROPAGATION */
 814
 815
 816 /**
 817  * Reply to client with the result from our lookup.
 818  *
 819  * @param cls the closure (our client lookup handle)
 820  * @param rd_count the number of records in @a rd
 821  * @param rd the record data
 822  */
 823 static void
 824 send_lookup_response (void* cls,
 825                       uint32_t rd_count,
 826                       const struct GNUNET_GNSRECORD_Data *rd)
 827 {
 828   struct ClientLookupHandle *clh = cls;
 829   struct GNUNET_MQ_Envelope *env;
 830   struct LookupResultMessage *rmsg;
 831   size_t len;
 832
 833   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 834               "Sending LOOKUP_RESULT message with %u results\n",
 835               (unsigned int) rd_count);
 836
 837   len = GNUNET_GNSRECORD_records_get_size (rd_count, rd);
 838   env = GNUNET_MQ_msg_extra (rmsg,
 839                              len,
 840                              GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT);
 841   rmsg->id = clh->request_id;
 842   rmsg->rd_count = htonl (rd_count);
 843   GNUNET_GNSRECORD_records_serialize (rd_count, rd, len,
 844                                       (char*) &rmsg[1]);
 845   GNUNET_MQ_send (GNUNET_SERVICE_client_get_mq(clh->gc->client),
 846                   env);
 847   GNUNET_CONTAINER_DLL_remove (clh->gc->clh_head, clh->gc->clh_tail, clh);
 848   GNUNET_free (clh);
 849   GNUNET_STATISTICS_update (statistics,
 850                             "Completed lookups", 1,
 851                             GNUNET_NO);
 852   GNUNET_STATISTICS_update (statistics,
 853                             "Records resolved",
 854                             rd_count,
 855                             GNUNET_NO);
 856 }
 857
 858 /**
 859  * Reply to client with the result from our reverse lookup.
 860  *
 861  * @param cls the closure (our client lookup handle)
 862  * @param rd_count the number of records in @a rd
 863  * @param rd the record data
 864  */
 865 static void
 866 send_reverse_lookup_response (void* cls,
 867                               const char *name)
 868 {
 869   struct ClientLookupHandle *clh = cls;
 870   struct GNUNET_MQ_Envelope *env;
 871   struct ReverseLookupResultMessage *rmsg;
 872   size_t len;
 873
 874   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 875               "Sending LOOKUP_RESULT message with %s\n",
 876               name);
 877
 878   if (NULL == name)
 879     len = 1;
 880   else
 881     len = strlen (name) + 1;
 882   env = GNUNET_MQ_msg_extra (rmsg,
 883                              len,
 884                              GNUNET_MESSAGE_TYPE_GNS_REVERSE_LOOKUP_RESULT);
 885   rmsg->id = clh->request_id;
 886   if (1 < len)
 887     GNUNET_memcpy ((char*) &rmsg[1],
 888                    name,
 889                    strlen (name));
 890   GNUNET_MQ_send (GNUNET_SERVICE_client_get_mq(clh->gc->client),
 891                   env);
 892   GNUNET_CONTAINER_DLL_remove (clh->gc->clh_head, clh->gc->clh_tail, clh);
 893   GNUNET_free (clh);
 894   GNUNET_STATISTICS_update (statistics,
 895                             "Completed reverse lookups", 1,
 896                             GNUNET_NO);
 897 }
 898
 899
 900 /**
 901  * Checks a #GNUNET_MESSAGE_TYPE_GNS_LOOKUP message
 902  *
 903  * @param cls client sending the message
 904  * @param l_msg message of type `struct LookupMessage`
 905  * @return #GNUNET_OK if @a l_msg is well-formed
 906  */
 907 static int
 908 check_lookup (void *cls,
 909               const struct LookupMessage *l_msg)
 910 {
 911   size_t msg_size;
 912   const char* name;
 913
 914   msg_size = ntohs (l_msg->header.size);
 915   if (msg_size < sizeof (struct LookupMessage))
 916   {
 917     GNUNET_break (0);
 918     return GNUNET_SYSERR;
 919   }
 920   name = (const char *) &l_msg[1];
 921   if ( ('\0' != name[msg_size - sizeof (struct LookupMessage) - 1]) ||
 922        (strlen (name) > GNUNET_DNSPARSER_MAX_NAME_LENGTH) )
 923   {
 924     GNUNET_break (0);
 925     return GNUNET_SYSERR;
 926   }
 927   return GNUNET_OK;
 928 }
 929
 930 /**
 931  * Handle lookup requests from client
 932  *
 933  * @param cls the closure
 934  * @param client the client
 935  * @param message the message
 936  */
 937 static void
 938 handle_lookup (void *cls,
 939                const struct LookupMessage *sh_msg)
 940 {
 941   struct GnsClient *gc = cls;
 942   char name[GNUNET_DNSPARSER_MAX_NAME_LENGTH + 1];
 943   struct ClientLookupHandle *clh;
 944   char *nameptr = name;
 945   const char *utf_in;
 946   const struct GNUNET_CRYPTO_EcdsaPrivateKey *key;
 947
 948   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 949               "Received LOOKUP message\n");
 950   GNUNET_SERVICE_client_continue (gc->client);
 951   if (GNUNET_YES == ntohs (sh_msg->have_key))
 952     key = &sh_msg->shorten_key;
 953   else
 954     key = NULL;
 955   utf_in = (const char *) &sh_msg[1];
 956   GNUNET_STRINGS_utf8_tolower (utf_in, nameptr);
 957
 958   clh = GNUNET_new (struct ClientLookupHandle);
 959   GNUNET_CONTAINER_DLL_insert (gc->clh_head, gc->clh_tail, clh);
 960   clh->gc = gc;
 961   clh->request_id = sh_msg->id;
 962   if ( (GNUNET_DNSPARSER_TYPE_A == ntohl (sh_msg->type)) &&
 963        (GNUNET_OK != v4_enabled) )
 964   {
 965     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 966                 "LOOKUP: Query for A record but AF_INET not supported!");
 967     send_lookup_response (clh, 0, NULL);
 968     return;
 969   }
 970   if ( (GNUNET_DNSPARSER_TYPE_AAAA == ntohl (sh_msg->type)) &&
 971        (GNUNET_OK != v6_enabled) )
 972   {
 973     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 974                 "LOOKUP: Query for AAAA record but AF_INET6 not supported!");
 975     send_lookup_response (clh, 0, NULL);
 976     return;
 977   }
 978   clh->lookup = GNS_resolver_lookup (&sh_msg->zone,
 979                                      ntohl (sh_msg->type),
 980                                      name,
 981                                      key,
 982                                      (enum GNUNET_GNS_LocalOptions) ntohs (sh_msg->options),
 983                                      &send_lookup_response, clh);
 984   GNUNET_STATISTICS_update (statistics,
 985                             "Lookup attempts",
 986                             1, GNUNET_NO);
 987 }
 988
 989 /**
 990  * Handle reverse lookup requests from client
 991  *
 992  * @param cls the closure
 993  * @param client the client
 994  * @param message the message
 995  */
 996 static void
 997 handle_rev_lookup (void *cls,
 998                    const struct ReverseLookupMessage *sh_msg)
 999 {
1000   struct GnsClient *gc = cls;
1001   struct ClientLookupHandle *clh;
1002
1003   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1004               "Received REVERSE_LOOKUP message\n");
1005   GNUNET_SERVICE_client_continue (gc->client);
1006
1007   clh = GNUNET_new (struct ClientLookupHandle);
1008   GNUNET_CONTAINER_DLL_insert (gc->clh_head, gc->clh_tail, clh);
1009   clh->gc = gc;
1010   clh->request_id = sh_msg->id;
1011   clh->rev_lookup = GNS_reverse_lookup (&sh_msg->zone_pkey,
1012                                         &sh_msg->root_pkey,
1013                                         &send_reverse_lookup_response,
1014                                         clh);
1015   GNUNET_STATISTICS_update (statistics,
1016                             "Reverse lookup attempts",
1017                             1, GNUNET_NO);
1018 }
1019
1020
1021 /**
1022  * The zone monitor is now in SYNC with the current state of the
1023  * name store.  Start to perform periodic iterations.
1024  *
1025  * @param cls NULL
1026  */
1027 static void
1028 monitor_sync_event (void *cls)
1029 {
1030   GNUNET_assert (NULL == zone_publish_task);
1031   zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
1032                                                 NULL);
1033 }
1034
1035
1036 /**
1037  * The zone monitor is now in SYNC with the current state of the
1038  * name store.  Start to perform periodic iterations.
1039  *
1040  * @param cls NULL
1041  */
1042 static void
1043 handle_monitor_error (void *cls)
1044 {
1045   if (NULL != zone_publish_task)
1046   {
1047     GNUNET_SCHEDULER_cancel (zone_publish_task);
1048     zone_publish_task = NULL;
1049   }
1050   if (NULL != namestore_iter)
1051   {
1052     GNUNET_NAMESTORE_zone_iteration_stop (namestore_iter);
1053     namestore_iter = NULL;
1054   }
1055   if (NULL != active_put)
1056   {
1057     GNUNET_DHT_put_cancel (active_put);
1058     active_put = NULL;
1059   }
1060   zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
1061                                                 NULL);
1062 }
1063
1064
1065 /**
1066  * Method called to inform about the ego to be used for the master zone
1067  * for DNS interceptions.
1068  *
1069  * This function is only called ONCE, and 'NULL' being passed in
1070  * @a ego does indicate that interception is not configured.
1071  * If @a ego is non-NULL, we should start to intercept DNS queries
1072  * and resolve ".gnu" queries using the given ego as the master zone.
1073  *
1074  * @param cls closure, our `const struct GNUNET_CONFIGURATION_Handle *c`
1075  * @param ego ego handle
1076  * @param ctx context for application to store data for this ego
1077  *                 (during the lifetime of this process, initially NULL)
1078  * @param name name assigned by the user for this ego,
1079  *                   NULL if the user just deleted the ego and it
1080  *                   must thus no longer be used
1081  */
1082 static void
1083 identity_intercept_cb (void *cls,
1084                        struct GNUNET_IDENTITY_Ego *ego,
1085                        void **ctx,
1086                        const char *name)
1087 {
1088   const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
1089   struct GNUNET_CRYPTO_EcdsaPublicKey dns_root;
1090
1091   identity_op = NULL;
1092   if (NULL == ego)
1093   {
1094     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1095                 _("No ego configured for `%s`\n"),
1096                 "gns-intercept");
1097     return;
1098   }
1099   GNUNET_IDENTITY_ego_get_public_key (ego,
1100                                       &dns_root);
1101   if (GNUNET_SYSERR ==
1102       GNS_interceptor_init (&dns_root, cfg))
1103   {
1104     GNUNET_break (0);
1105     GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
1106     return;
1107   }
1108 }
1109
1110
1111 /**
1112  * Process GNS requests.
1113  *
1114  * @param cls closure
1115  * @param server the initialized server
1116  * @param c configuration to use
1117  */
1118 static void
1119 run (void *cls,
1120      const struct GNUNET_CONFIGURATION_Handle *c,
1121      struct GNUNET_SERVICE_Handle *service)
1122 {
1123   unsigned long long max_parallel_bg_queries = 0;
1124
1125   v6_enabled = GNUNET_NETWORK_test_pf (PF_INET6);
1126   v4_enabled = GNUNET_NETWORK_test_pf (PF_INET);
1127   min_relative_record_time = GNUNET_TIME_UNIT_FOREVER_REL;
1128   namestore_handle = GNUNET_NAMESTORE_connect (c);
1129   if (NULL == namestore_handle)
1130   {
1131     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1132                 _("Failed to connect to the namestore!\n"));
1133     GNUNET_SCHEDULER_shutdown ();
1134     return;
1135   }
1136   namecache_handle = GNUNET_NAMECACHE_connect (c);
1137   if (NULL == namecache_handle)
1138   {
1139     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1140                 _("Failed to connect to the namecache!\n"));
1141     GNUNET_SCHEDULER_shutdown ();
1142     return;
1143   }
1144
1145   put_interval = INITIAL_PUT_INTERVAL;
1146   zone_publish_time_window_default = DEFAULT_ZONE_PUBLISH_TIME_WINDOW;
1147   if (GNUNET_OK ==
1148       GNUNET_CONFIGURATION_get_value_time (c, "gns",
1149                                            "ZONE_PUBLISH_TIME_WINDOW",
1150                                            &zone_publish_time_window_default))
1151   {
1152     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1153                 "Time window for zone iteration: %s\n",
1154                 GNUNET_STRINGS_relative_time_to_string (zone_publish_time_window,
1155                                                         GNUNET_YES));
1156   }
1157   zone_publish_time_window = zone_publish_time_window_default;
1158   if (GNUNET_OK ==
1159       GNUNET_CONFIGURATION_get_value_number (c, "gns",
1160                                              "MAX_PARALLEL_BACKGROUND_QUERIES",
1161                                              &max_parallel_bg_queries))
1162   {
1163     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1164                 "Number of allowed parallel background queries: %llu\n",
1165                 max_parallel_bg_queries);
1166   }
1167
1168   dht_handle = GNUNET_DHT_connect (c,
1169                                    (unsigned int) max_parallel_bg_queries);
1170   if (NULL == dht_handle)
1171   {
1172     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1173                 _("Could not connect to DHT!\n"));
1174     GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
1175     return;
1176   }
1177
1178   identity_handle = GNUNET_IDENTITY_connect (c,
1179                                              NULL,
1180                                              NULL);
1181   if (NULL == identity_handle)
1182   {
1183     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1184                 "Could not connect to identity service!\n");
1185   }
1186   else
1187   {
1188     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1189                 "Looking for gns-intercept ego\n");
1190     identity_op = GNUNET_IDENTITY_get (identity_handle,
1191                                        "gns-intercept",
1192                                        &identity_intercept_cb,
1193                                        (void *) c);
1194   }
1195   GNS_resolver_init (namecache_handle,
1196                      dht_handle,
1197                      c,
1198                      max_parallel_bg_queries);
1199   GNS_shorten_init (namestore_handle,
1200                     namecache_handle,
1201                     dht_handle);
1202   /* Schedule periodic put for our records. */
1203   first_zone_iteration = GNUNET_YES;
1204   statistics = GNUNET_STATISTICS_create ("gns", c);
1205   zmon = GNUNET_NAMESTORE_zone_monitor_start (c,
1206                                               NULL,
1207                                               GNUNET_NO,
1208                                               &handle_monitor_error,
1209                                               NULL,
1210                                               &handle_monitor_event,
1211                                               NULL,
1212                                               &monitor_sync_event,
1213                                               NULL);
1214   GNUNET_break (NULL != zmon);
1215   GNUNET_SCHEDULER_add_shutdown (&shutdown_task, NULL);
1216 }
1217
1218
1219 /**
1220  * Define "main" method using service macro.
1221  */
1222 GNUNET_SERVICE_MAIN
1223 ("gns",
1224  GNUNET_SERVICE_OPTION_NONE,
1225  &run,
1226  &client_connect_cb,
1227  &client_disconnect_cb,
1228  NULL,
1229  GNUNET_MQ_hd_var_size (lookup,
1230                         GNUNET_MESSAGE_TYPE_GNS_LOOKUP,
1231                         struct LookupMessage,
1232                         NULL),
1233  GNUNET_MQ_hd_fixed_size (rev_lookup,
1234                           GNUNET_MESSAGE_TYPE_GNS_REVERSE_LOOKUP,
1235                           struct ReverseLookupMessage,
1236                           NULL),
1237  GNUNET_MQ_handler_end());
1238
1239
1240 /* end of gnunet-service-gns.c */