src/dv/gnunet-service-dv.c

   1 /*
   2      This file is part of GNUnet.
   3      Copyright (C) 2013, 2016 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 /**
  22  * @file dv/gnunet-service-dv.c
  23  * @brief the distance vector service, primarily handles gossip of nearby
  24  * peers and sending/receiving DV messages from core and decapsulating
  25  * them
  26  *
  27  * @author Christian Grothoff
  28  * @author Nathan Evans
  29  */
  30 #include "platform.h"
  31 #include "gnunet_util_lib.h"
  32 #include "gnunet_protocols.h"
  33 #include "gnunet_core_service.h"
  34 #include "gnunet_hello_lib.h"
  35 #include "gnunet_peerinfo_service.h"
  36 #include "gnunet_statistics_service.h"
  37 #include "gnunet_set_service.h"
  38 #include "gnunet_ats_service.h"
  39 #include "dv.h"
  40 #include <gcrypt.h>
  41
  42
  43 /**
  44  * How often do we establish the consensu?
  45  */
  46 #define GNUNET_DV_CONSENSUS_FREQUENCY GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 5)
  47
  48 /**
  49  * Maximum number of messages we queue per peer.
  50  */
  51 #define MAX_QUEUE_SIZE 16
  52
  53 /**
  54  * Maximum number of messages we queue towards the clients/plugin.
  55  */
  56 #define MAX_QUEUE_SIZE_PLUGIN 1024
  57
  58 /**
  59  * The default fisheye depth, from how many hops away will
  60  * we keep peers?
  61  */
  62 #define DEFAULT_FISHEYE_DEPTH 3
  63
  64 /**
  65  * How many hops is a direct neighbor away?
  66  */
  67 #define DIRECT_NEIGHBOR_COST 1
  68
  69
  70 GNUNET_NETWORK_STRUCT_BEGIN
  71
  72 /**
  73  * Information about a peer DV can route to.  These entries are what
  74  * we use as the binary format to establish consensus to create our
  75  * routing table and as the address format in the HELLOs.
  76  */
  77 struct Target
  78 {
  79
  80   /**
  81    * Identity of the peer we can reach.
  82    */
  83   struct GNUNET_PeerIdentity peer;
  84
  85   /**
  86    * How many hops (1-3) is this peer away? in network byte order
  87    */
  88   uint32_t distance GNUNET_PACKED;
  89
  90 };
  91
  92
  93 /**
  94  * Message exchanged between DV services (via core), requesting a
  95  * message to be routed.
  96  */
  97 struct RouteMessage
  98 {
  99   /**
 100    * Type: #GNUNET_MESSAGE_TYPE_DV_ROUTE
 101    */
 102   struct GNUNET_MessageHeader header;
 103
 104   /**
 105    * Expected (remaining) distance.  Must be always smaller than
 106    * #DEFAULT_FISHEYE_DEPTH, should be zero at the target.  Must
 107    * be decremented by one at each hop.  Peers must not forward
 108    * these messages further once the counter has reached zero.
 109    */
 110   uint32_t distance GNUNET_PACKED;
 111
 112   /**
 113    * The (actual) target of the message (this peer, if distance is zero).
 114    */
 115   struct GNUNET_PeerIdentity target;
 116
 117   /**
 118    * The (actual) sender of the message.
 119    */
 120   struct GNUNET_PeerIdentity sender;
 121
 122 };
 123
 124 GNUNET_NETWORK_STRUCT_END
 125
 126
 127 /**
 128  * Information about a direct neighbor (core-level, excluding
 129  * DV-links, only DV-enabled peers).
 130  */
 131 struct DirectNeighbor
 132 {
 133
 134   /**
 135    * Identity of the peer.
 136    */
 137   struct GNUNET_PeerIdentity peer;
 138
 139   /**
 140    * Session ID we use whenever we create a set union with
 141    * this neighbor; constructed from the XOR of our peer
 142    * IDs and then salted with "DV-SALT" to avoid conflicts
 143    * with other applications.
 144    */
 145   struct GNUNET_HashCode real_session_id;
 146
 147   /**
 148    * Transmit handle to core service.
 149    */
 150   struct GNUNET_MQ_Handle *mq;
 151
 152   /**
 153    * Routing table of the neighbor, NULL if not yet established.
 154    * Keys are peer identities, values are 'struct Target' entries.
 155    * Note that the distances in the targets are from the point-of-view
 156    * of the peer, not from us!
 157    */
 158   struct GNUNET_CONTAINER_MultiPeerMap *neighbor_table;
 159
 160   /**
 161    * Updated routing table of the neighbor, under construction,
 162    * NULL if we are not currently building it.
 163    * Keys are peer identities, values are 'struct Target' entries.
 164    * Note that the distances in the targets are from the point-of-view
 165    * of the other peer, not from us!
 166    */
 167   struct GNUNET_CONTAINER_MultiPeerMap *neighbor_table_consensus;
 168
 169   /**
 170    * Our current (exposed) routing table as a set.
 171    */
 172   struct GNUNET_SET_Handle *my_set;
 173
 174   /**
 175    * Handle for our current active set union operation.
 176    */
 177   struct GNUNET_SET_OperationHandle *set_op;
 178
 179   /**
 180    * Handle used if we are listening for this peer, waiting for the
 181    * other peer to initiate construction of the set union.  NULL if
 182    * we ar the initiating peer.
 183    */
 184   struct GNUNET_SET_ListenHandle *listen_handle;
 185
 186   /**
 187    * ID of the task we use to (periodically) update our consensus
 188    * with this peer.  Used if we are the initiating peer.
 189    */
 190   struct GNUNET_SCHEDULER_Task *initiate_task;
 191
 192   /**
 193    * At what offset are we, with respect to inserting our own routes
 194    * into the consensus?
 195    */
 196   unsigned int consensus_insertion_offset;
 197
 198   /**
 199    * At what distance are we, with respect to inserting our own routes
 200    * into the consensus?
 201    */
 202   unsigned int consensus_insertion_distance;
 203
 204   /**
 205    * Elements in consensus
 206    */
 207   unsigned int consensus_elements;
 208
 209   /**
 210    * Direct one hop route
 211    */
 212   struct Route *direct_route;
 213
 214   /**
 215    * Flag set within 'check_target_removed' to trigger full global route refresh.
 216    */
 217   int target_removed;
 218
 219   /**
 220    * Our distance to this peer, 0 for unknown.
 221    */
 222   uint32_t distance;
 223
 224   /**
 225    * The network this peer is in
 226    */
 227   enum GNUNET_ATS_Network_Type network;
 228
 229   /**
 230    * Is this neighbor connected at the core level?
 231    */
 232   int connected;
 233
 234 };
 235
 236
 237 /**
 238  * A route includes information about the next hop,
 239  * the target, and the ultimate distance to the
 240  * target.
 241  */
 242 struct Route
 243 {
 244
 245   /**
 246    * Which peer do we need to forward the message to?
 247    */
 248   struct DirectNeighbor *next_hop;
 249
 250   /**
 251    * What would be the target, and how far is it away?
 252    */
 253   struct Target target;
 254
 255   /**
 256    * Offset of this target in the respective consensus set.
 257    */
 258   unsigned int set_offset;
 259
 260 };
 261
 262
 263 /**
 264  * Set of targets we bring to a consensus; all targets in a set have a
 265  * distance equal to the sets distance (which is implied by the array
 266  * index of the set).
 267  */
 268 struct ConsensusSet
 269 {
 270
 271   /**
 272    * Array of targets in the set, may include NULL entries if a
 273    * neighbor has disconnected; the targets are allocated with the
 274    * respective container (all_routes), not here.
 275    */
 276   struct Route **targets;
 277
 278   /**
 279    * Size of the @e targets array.
 280    */
 281   unsigned int array_length;
 282
 283 };
 284
 285
 286 /**
 287  * Peermap of all of our neighbors; processing these usually requires
 288  * first checking to see if the peer is core-connected and if the
 289  * distance is 1, in which case they are direct neighbors.
 290  */
 291 static struct GNUNET_CONTAINER_MultiPeerMap *direct_neighbors;
 292
 293 /**
 294  * Hashmap with all routes that we currently support; contains
 295  * routing information for all peers from distance 2
 296  * up to distance #DEFAULT_FISHEYE_DEPTH.
 297  */
 298 static struct GNUNET_CONTAINER_MultiPeerMap *all_routes;
 299
 300 /**
 301  * Array of consensus sets we expose to the outside world.  Sets
 302  * are structured by the distance to the target.
 303  */
 304 static struct ConsensusSet consensi[DEFAULT_FISHEYE_DEPTH];
 305
 306 /**
 307  * Handle to the core service api.
 308  */
 309 static struct GNUNET_CORE_Handle *core_api;
 310
 311 /**
 312  * The identity of our peer.
 313  */
 314 static struct GNUNET_PeerIdentity my_identity;
 315
 316 /**
 317  * The configuration for this service.
 318  */
 319 static const struct GNUNET_CONFIGURATION_Handle *cfg;
 320
 321 /**
 322  * The client, the DV plugin connected to us (or an event monitor).
 323  * Hopefully this client will never change, although if the plugin
 324  * dies and returns for some reason it may happen.
 325  */
 326 static struct GNUNET_NotificationContext *nc;
 327
 328 /**
 329  * Handle for the statistics service.
 330  */
 331 static struct GNUNET_STATISTICS_Handle *stats;
 332
 333 /**
 334  * Handle to ATS service.
 335  */
 336 static struct GNUNET_ATS_PerformanceHandle *ats;
 337
 338 /**
 339  * Task scheduled to refresh routes based on direct neighbours.
 340  */
 341 static struct GNUNET_SCHEDULER_Task *rr_task;
 342
 343 /**
 344  * #GNUNET_YES if we are shutting down.
 345  */
 346 static int in_shutdown;
 347
 348 /**
 349  * Start creating a new DV set union by initiating the connection.
 350  *
 351  * @param cls the 'struct DirectNeighbor' of the peer we're building
 352  *        a routing consensus with
 353  */
 354 static void
 355 initiate_set_union (void *cls);
 356
 357
 358 /**
 359  * Start creating a new DV set union construction, our neighbour has
 360  * asked for it (callback for listening peer).
 361  *
 362  * @param cls the 'struct DirectNeighbor' of the peer we're building
 363  *        a routing consensus with
 364  * @param other_peer the other peer
 365  * @param context_msg message with application specific information from
 366  *        the other peer
 367  * @param request request from the other peer, use GNUNET_SET_accept
 368  *        to accept it, otherwise the request will be refused
 369  *        Note that we don't use a return value here, as it is also
 370  *        necessary to specify the set we want to do the operation with,
 371  *        whith sometimes can be derived from the context message.
 372  *        Also necessary to specify the timeout.
 373  */
 374 static void
 375 listen_set_union (void *cls,
 376                   const struct GNUNET_PeerIdentity *other_peer,
 377                   const struct GNUNET_MessageHeader *context_msg,
 378                   struct GNUNET_SET_Request *request);
 379
 380
 381 /**
 382  * Forward a message from another peer to the plugin.
 383  *
 384  * @param message the message to send to the plugin
 385  * @param origin the original sender of the message
 386  * @param distance distance to the original sender of the message
 387  */
 388 static void
 389 send_data_to_plugin (const struct GNUNET_MessageHeader *message,
 390                      const struct GNUNET_PeerIdentity *origin,
 391                      uint32_t distance)
 392 {
 393   struct GNUNET_DV_ReceivedMessage *received_msg;
 394   size_t size;
 395
 396   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 397               "Delivering message from peer `%s' at distance %u\n",
 398               GNUNET_i2s (origin),
 399               (unsigned int) distance);
 400   size = sizeof (struct GNUNET_DV_ReceivedMessage) +
 401     ntohs (message->size);
 402   if (size >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
 403   {
 404     GNUNET_break (0); /* too big */
 405     return;
 406   }
 407   received_msg = GNUNET_malloc (size);
 408   received_msg->header.size = htons (size);
 409   received_msg->header.type = htons (GNUNET_MESSAGE_TYPE_DV_RECV);
 410   received_msg->distance = htonl (distance);
 411   received_msg->sender = *origin;
 412   GNUNET_memcpy (&received_msg[1], message, ntohs (message->size));
 413   GNUNET_notification_context_broadcast (nc,
 414                                          &received_msg->header,
 415                                          GNUNET_YES);
 416   GNUNET_free (received_msg);
 417 }
 418
 419
 420 /**
 421  * Forward a control message to the plugin.
 422  *
 423  * @param message the message to send to the plugin
 424  */
 425 static void
 426 send_control_to_plugin (const struct GNUNET_MessageHeader *message)
 427 {
 428   GNUNET_notification_context_broadcast (nc,
 429                                          message,
 430                                          GNUNET_NO);
 431 }
 432
 433
 434 /**
 435  * Send a DISTANCE_CHANGED message to the plugin.
 436  *
 437  * @param peer peer with a changed distance
 438  * @param distance new distance to the peer
 439  * @param network network used by the neighbor
 440  */
 441 static void
 442 send_distance_change_to_plugin (const struct GNUNET_PeerIdentity *peer,
 443                                 uint32_t distance,
 444                                 enum GNUNET_ATS_Network_Type network)
 445 {
 446   struct GNUNET_DV_DistanceUpdateMessage du_msg;
 447
 448   GNUNET_break (GNUNET_ATS_NET_UNSPECIFIED != network);
 449   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 450               "Delivering DISTANCE_CHANGED for message about peer `%s'\n",
 451               GNUNET_i2s (peer));
 452   du_msg.header.size = htons (sizeof (du_msg));
 453   du_msg.header.type = htons (GNUNET_MESSAGE_TYPE_DV_DISTANCE_CHANGED);
 454   du_msg.distance = htonl (distance);
 455   du_msg.peer = *peer;
 456   du_msg.network = htonl ((uint32_t) network);
 457   send_control_to_plugin (&du_msg.header);
 458 }
 459
 460
 461 /**
 462  * Give a CONNECT message to the plugin.
 463  *
 464  * @param target peer that connected
 465  * @param distance distance to the target
 466  * @param network the network the next hop is located in
 467  */
 468 static void
 469 send_connect_to_plugin (const struct GNUNET_PeerIdentity *target,
 470                         uint32_t distance,
 471                         enum GNUNET_ATS_Network_Type network)
 472 {
 473   struct GNUNET_DV_ConnectMessage cm;
 474
 475   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 476               "Delivering CONNECT about peer %s with distance %u\n",
 477               GNUNET_i2s (target), distance);
 478   cm.header.size = htons (sizeof (cm));
 479   cm.header.type = htons (GNUNET_MESSAGE_TYPE_DV_CONNECT);
 480   cm.distance = htonl (distance);
 481   cm.network = htonl ((uint32_t) network);
 482   cm.peer = *target;
 483   send_control_to_plugin (&cm.header);
 484 }
 485
 486
 487 /**
 488  * Give a DISCONNECT message to the plugin.
 489  *
 490  * @param target peer that disconnected
 491  */
 492 static void
 493 send_disconnect_to_plugin (const struct GNUNET_PeerIdentity *target)
 494 {
 495   struct GNUNET_DV_DisconnectMessage dm;
 496
 497   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 498               "Delivering DISCONNECT about peer `%s'\n",
 499               GNUNET_i2s (target));
 500   dm.header.size = htons (sizeof (dm));
 501   dm.header.type = htons (GNUNET_MESSAGE_TYPE_DV_DISCONNECT);
 502   dm.reserved = htonl (0);
 503   dm.peer = *target;
 504   send_control_to_plugin (&dm.header);
 505 }
 506
 507
 508 /**
 509  * Forward the given payload to the given target.
 510  *
 511  * @param target where to send the message
 512  * @param distance distance to the @a sender
 513  * @param sender original sender of the message
 514  * @param actual_target ultimate recipient for the message
 515  * @param payload payload of the message
 516  */
 517 static void
 518 forward_payload (struct DirectNeighbor *target,
 519                  uint32_t distance,
 520                  const struct GNUNET_PeerIdentity *sender,
 521                  const struct GNUNET_PeerIdentity *actual_target,
 522                  const struct GNUNET_MessageHeader *payload)
 523 {
 524   struct GNUNET_MQ_Envelope *env;
 525   struct RouteMessage *rm;
 526
 527   if ( (GNUNET_MQ_get_length (target->mq) >= MAX_QUEUE_SIZE) &&
 528        (0 != memcmp (sender,
 529                      &my_identity,
 530                      sizeof (struct GNUNET_PeerIdentity))) )
 531   {
 532     /* not _our_ client and queue is full, drop */
 533     GNUNET_STATISTICS_update (stats,
 534                               "# messages dropped",
 535                               1,
 536                               GNUNET_NO);
 537     return;
 538   }
 539   if (sizeof (struct RouteMessage) + ntohs (payload->size)
 540       >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
 541   {
 542     GNUNET_break (0);
 543     return;
 544   }
 545   env = GNUNET_MQ_msg_nested_mh (rm,
 546                                  GNUNET_MESSAGE_TYPE_DV_ROUTE,
 547                                  payload);
 548   rm->distance = htonl (distance);
 549   rm->target = *actual_target;
 550   rm->sender = *sender;
 551   GNUNET_MQ_send (target->mq,
 552                   env);
 553 }
 554
 555
 556 /**
 557  * Find a free slot for storing a 'route' in the 'consensi'
 558  * set at the given distance.
 559  *
 560  * @param distance distance to use for the set slot
 561  */
 562 static unsigned int
 563 get_consensus_slot (uint32_t distance)
 564 {
 565   struct ConsensusSet *cs;
 566   unsigned int i;
 567
 568   GNUNET_assert (distance < DEFAULT_FISHEYE_DEPTH);
 569   cs = &consensi[distance];
 570   i = 0;
 571   while ( (i < cs->array_length) &&
 572           (NULL != cs->targets[i]) ) i++;
 573   if (i == cs->array_length)
 574   {
 575     GNUNET_array_grow (cs->targets,
 576                        cs->array_length,
 577                        cs->array_length * 2 + 2);
 578   }
 579   return i;
 580 }
 581
 582
 583 /**
 584  * Allocate a slot in the consensus set for a route.
 585  *
 586  * @param route route to initialize
 587  * @param distance which consensus set to use
 588  */
 589 static void
 590 allocate_route (struct Route *route,
 591                 uint32_t distance)
 592 {
 593   unsigned int i;
 594
 595   if (distance >= DEFAULT_FISHEYE_DEPTH)
 596   {
 597     route->target.distance = htonl (distance);
 598     route->set_offset = UINT_MAX; /* invalid slot */
 599     return;
 600   }
 601   i = get_consensus_slot (distance);
 602   route->set_offset = i;
 603   consensi[distance].targets[i] = route;
 604   route->target.distance = htonl (distance);
 605 }
 606
 607
 608 /**
 609  * Release a slot in the consensus set for a route.
 610  *
 611  * @param route route to release the slot from
 612  */
 613 static void
 614 release_route (struct Route *route)
 615 {
 616   if (UINT_MAX == route->set_offset)
 617     return;
 618   GNUNET_assert (ntohl (route->target.distance) < DEFAULT_FISHEYE_DEPTH);
 619   consensi[ntohl (route->target.distance)].targets[route->set_offset] = NULL;
 620   route->set_offset = UINT_MAX; /* indicate invalid slot */
 621 }
 622
 623
 624 /**
 625  * Move a route from one consensus set to another.
 626  *
 627  * @param route route to move
 628  * @param new_distance new distance for the route (destination set)
 629  */
 630 static void
 631 move_route (struct Route *route,
 632             uint32_t new_distance)
 633 {
 634   release_route (route);
 635   allocate_route (route, new_distance);
 636 }
 637
 638
 639 /**
 640  * Initialize this neighbors 'my_set' and when done give
 641  * it to the pending set operation for execution.
 642  *
 643  * Add a single element to the set per call:
 644  *
 645  * If we reached the last element of a consensus element: increase distance
 646  *
 647  *
 648  * @param cls the neighbor for which we are building the set
 649  */
 650 static void
 651 build_set (void *cls)
 652 {
 653   struct DirectNeighbor *neighbor = cls;
 654   struct GNUNET_SET_Element element;
 655   struct Target *target;
 656   struct Route *route;
 657
 658   target = NULL;
 659   /* skip over NULL entries */
 660   while ( (DEFAULT_FISHEYE_DEPTH > neighbor->consensus_insertion_distance) &&
 661           (consensi[neighbor->consensus_insertion_distance].array_length > neighbor->consensus_insertion_offset) &&
 662           (NULL == consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset]) )
 663     neighbor->consensus_insertion_offset++;
 664   while ( (DEFAULT_FISHEYE_DEPTH > neighbor->consensus_insertion_distance) &&
 665           (consensi[neighbor->consensus_insertion_distance].array_length == neighbor->consensus_insertion_offset) )
 666   {
 667     /* If we reached the last element of a consensus array element: increase distance and start with next array */
 668     neighbor->consensus_insertion_offset = 0;
 669     neighbor->consensus_insertion_distance++;
 670     /* skip over NULL entries */
 671     while ( (DEFAULT_FISHEYE_DEPTH > neighbor->consensus_insertion_distance) &&
 672             (consensi[neighbor->consensus_insertion_distance].array_length  > neighbor->consensus_insertion_offset) &&
 673             (NULL == consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset]) )
 674       neighbor->consensus_insertion_offset++;
 675   }
 676   if (DEFAULT_FISHEYE_DEPTH == neighbor->consensus_insertion_distance)
 677   {
 678     /* we have added all elements to the set, run the operation */
 679     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 680                 "Finished building my SET for peer `%s' with %u elements, committing\n",
 681                 GNUNET_i2s (&neighbor->peer),
 682                 neighbor->consensus_elements);
 683     GNUNET_SET_commit (neighbor->set_op,
 684                        neighbor->my_set);
 685     GNUNET_SET_destroy (neighbor->my_set);
 686     neighbor->my_set = NULL;
 687     return;
 688   }
 689
 690   route = consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset];
 691   GNUNET_assert (NULL != route);
 692   target = &route->target;
 693   GNUNET_assert (ntohl (target->distance) < DEFAULT_FISHEYE_DEPTH);
 694   element.size = sizeof (struct Target);
 695   element.element_type = htons (0);
 696   element.data = target;
 697
 698   /* Find next non-NULL entry */
 699   neighbor->consensus_insertion_offset++;
 700   if ( (0 != memcmp (&target->peer,
 701                      &my_identity,
 702                      sizeof (my_identity))) &&
 703        (0 != memcmp (&target->peer,
 704                      &neighbor->peer,
 705                      sizeof (struct GNUNET_PeerIdentity))) )
 706   {
 707     /* Add target if it is not the neighbor or this peer */
 708     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 709                 "Adding peer `%s' with distance %u to SET\n",
 710                 GNUNET_i2s (&target->peer),
 711                 ntohl (target->distance) + 1);
 712     GNUNET_SET_add_element (neighbor->my_set,
 713                             &element,
 714                             &build_set, neighbor);
 715     neighbor->consensus_elements++;
 716   }
 717   else
 718     build_set (neighbor);
 719 }
 720
 721
 722 /**
 723  * A peer is now connected to us at distance 1.  Initiate DV exchange.
 724  *
 725  * @param neighbor entry for the neighbor at distance 1
 726  */
 727 static void
 728 handle_direct_connect (struct DirectNeighbor *neighbor)
 729 {
 730   struct Route *route;
 731   struct GNUNET_HashCode h1;
 732   struct GNUNET_HashCode h2;
 733   struct GNUNET_HashCode session_id;
 734
 735   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 736               "Direct connection to %s established, routing table exchange begins.\n",
 737               GNUNET_i2s (&neighbor->peer));
 738   GNUNET_STATISTICS_update (stats,
 739                             "# peers connected (1-hop)",
 740                             1, GNUNET_NO);
 741   route = GNUNET_CONTAINER_multipeermap_get (all_routes,
 742                                              &neighbor->peer);
 743   if (NULL != route)
 744   {
 745     GNUNET_assert (GNUNET_YES ==
 746                    GNUNET_CONTAINER_multipeermap_remove (all_routes,
 747                                                          &neighbor->peer,
 748                                                          route));
 749     send_disconnect_to_plugin (&neighbor->peer);
 750     release_route (route);
 751     GNUNET_free (route);
 752   }
 753
 754   neighbor->direct_route = GNUNET_new (struct Route);
 755   neighbor->direct_route->next_hop = neighbor;
 756   neighbor->direct_route->target.peer = neighbor->peer;
 757   allocate_route (neighbor->direct_route, DIRECT_NEIGHBOR_COST);
 758
 759   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 760               "Adding direct route to %s\n",
 761               GNUNET_i2s (&neighbor->direct_route->target.peer));
 762
 763
 764   /* construct session ID seed as XOR of both peer's identities */
 765   GNUNET_CRYPTO_hash (&my_identity,
 766                       sizeof (my_identity),
 767                       &h1);
 768   GNUNET_CRYPTO_hash (&neighbor->peer,
 769                       sizeof (struct GNUNET_PeerIdentity),
 770                       &h2);
 771   GNUNET_CRYPTO_hash_xor (&h1,
 772                           &h2,
 773                           &session_id);
 774   /* make sure session ID is unique across applications by salting it with 'DV' */
 775   GNUNET_CRYPTO_hkdf (&neighbor->real_session_id, sizeof (struct GNUNET_HashCode),
 776                       GCRY_MD_SHA512, GCRY_MD_SHA256,
 777                       "DV-SALT", 2,
 778                       &session_id, sizeof (session_id),
 779                       NULL, 0);
 780   if (0 < memcmp (&neighbor->peer,
 781                   &my_identity,
 782                   sizeof (struct GNUNET_PeerIdentity)))
 783   {
 784     if (NULL != neighbor->listen_handle)
 785     {
 786       GNUNET_break (0);
 787     }
 788     else
 789       neighbor->initiate_task = GNUNET_SCHEDULER_add_now (&initiate_set_union,
 790                                                           neighbor);
 791   }
 792   else
 793   {
 794     if (NULL != neighbor->listen_handle)
 795     {
 796       GNUNET_break (0);
 797     }
 798     else
 799     {
 800       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 801                   "Starting SET listen operation with peer `%s'\n",
 802                   GNUNET_i2s (&neighbor->peer));
 803       neighbor->listen_handle = GNUNET_SET_listen (cfg,
 804                                                    GNUNET_SET_OPERATION_UNION,
 805                                                    &neighbor->real_session_id,
 806                                                    &listen_set_union,
 807                                                    neighbor);
 808     }
 809   }
 810 }
 811
 812
 813 /**
 814  * Method called whenever a peer connects.
 815  *
 816  * @param cls closure
 817  * @param peer peer identity this notification is about
 818  * @param mq message queue for sending data to @a peer
 819  * @return our `struct DirectNeighbour` for this peer
 820  */
 821 static void *
 822 handle_core_connect (void *cls,
 823                      const struct GNUNET_PeerIdentity *peer,
 824                      struct GNUNET_MQ_Handle *mq)
 825 {
 826   struct DirectNeighbor *neighbor;
 827
 828   /* Check for connect to self message */
 829   if (0 == memcmp (&my_identity,
 830                    peer,
 831                    sizeof (struct GNUNET_PeerIdentity)))
 832     return NULL;
 833   /* check if entry exists */
 834   neighbor = GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
 835                                                 peer);
 836   if (NULL != neighbor)
 837   {
 838     GNUNET_break (GNUNET_ATS_NET_UNSPECIFIED != neighbor->network);
 839     GNUNET_break (GNUNET_YES != neighbor->connected);
 840     neighbor->connected = GNUNET_YES;
 841     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 842                 "Core connected to %s (distance %u)\n",
 843                 GNUNET_i2s (peer),
 844                 (unsigned int) neighbor->distance);
 845     if (DIRECT_NEIGHBOR_COST != neighbor->distance)
 846       return NULL;
 847     handle_direct_connect (neighbor);
 848     return NULL;
 849   }
 850   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 851               "Core connected to %s (distance unknown)\n",
 852               GNUNET_i2s (peer));
 853   neighbor = GNUNET_new (struct DirectNeighbor);
 854   neighbor->peer = *peer;
 855   GNUNET_assert (GNUNET_YES ==
 856                  GNUNET_CONTAINER_multipeermap_put (direct_neighbors,
 857                                                     &neighbor->peer,
 858                                                     neighbor,
 859                                                     GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
 860   neighbor->connected = GNUNET_YES;
 861   neighbor->distance = 0; /* unknown */
 862   neighbor->network = GNUNET_ATS_NET_UNSPECIFIED;
 863   return neighbor;
 864 }
 865
 866
 867 /**
 868  * Called for each 'target' in a neighbor table to free the associated memory.
 869  *
 870  * @param cls NULL
 871  * @param key key of the value
 872  * @param value value to free
 873  * @return #GNUNET_OK to continue to iterate
 874  */
 875 static int
 876 free_targets (void *cls,
 877               const struct GNUNET_PeerIdentity *key,
 878               void *value)
 879 {
 880   GNUNET_free (value);
 881   return GNUNET_OK;
 882 }
 883
 884
 885 /**
 886  * Add a new route to the given @a target via the given @a neighbor.
 887  *
 888  * @param target the target of the route
 889  * @param neighbor the next hop for communicating with the @a target
 890  */
 891 static void
 892 add_new_route (struct Target *target,
 893                struct DirectNeighbor *neighbor)
 894 {
 895   struct Route *route;
 896
 897   route = GNUNET_new (struct Route);
 898   route->next_hop = neighbor;
 899   route->target.peer = target->peer;
 900   allocate_route (route, ntohl (target->distance) + 1);
 901   GNUNET_assert (GNUNET_YES ==
 902                  GNUNET_CONTAINER_multipeermap_put (all_routes,
 903                                                     &route->target.peer,
 904                                                     route,
 905                                                     GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
 906   send_connect_to_plugin (&route->target.peer,
 907                           ntohl (route->target.distance),
 908                           neighbor->network);
 909 }
 910
 911
 912 /**
 913  * Multipeerhmap iterator for checking if a given route is
 914  * (now) useful to this peer.
 915  *
 916  * @param cls the direct neighbor for the given route
 917  * @param key key value stored under
 918  * @param value a 'struct Target' that may or may not be useful; not that
 919  *        the distance in 'target' does not include the first hop yet
 920  * @return #GNUNET_YES to continue iteration, #GNUNET_NO to stop
 921  */
 922 static int
 923 check_possible_route (void *cls,
 924                       const struct GNUNET_PeerIdentity *key,
 925                       void *value)
 926 {
 927   struct DirectNeighbor *neighbor = cls;
 928   struct Target *target = value;
 929   struct Route *route;
 930
 931   if (GNUNET_YES ==
 932       GNUNET_CONTAINER_multipeermap_contains (direct_neighbors,
 933                                               key))
 934     return GNUNET_YES; /* direct route, do not care about alternatives */
 935   route = GNUNET_CONTAINER_multipeermap_get (all_routes,
 936                                              key);
 937   if (NULL != route)
 938   {
 939     /* we have an existing route, check how it compares with going via 'target' */
 940     if (ntohl (route->target.distance) > ntohl (target->distance) + 1)
 941     {
 942       /* via 'target' is cheaper than the existing route; switch to alternative route! */
 943       move_route (route, ntohl (target->distance) + 1);
 944       route->next_hop = neighbor;
 945       send_distance_change_to_plugin (&target->peer,
 946                                       ntohl (target->distance) + 1,
 947                                       neighbor->network);
 948     }
 949     return GNUNET_YES; /* got a route to this target already */
 950   }
 951   if (ntohl (target->distance) >= DEFAULT_FISHEYE_DEPTH)
 952     return GNUNET_YES; /* distance is too large to be interesting */
 953   add_new_route (target, neighbor);
 954   return GNUNET_YES;
 955 }
 956
 957
 958 /**
 959  * Multipeermap iterator for finding routes that were previously
 960  * "hidden" due to a better route (called after a disconnect event).
 961  *
 962  * @param cls NULL
 963  * @param key peer identity of the given direct neighbor
 964  * @param value a `struct DirectNeighbor` to check for additional routes
 965  * @return #GNUNET_YES to continue iteration
 966  */
 967 static int
 968 refresh_routes (void *cls,
 969                 const struct GNUNET_PeerIdentity *key,
 970                 void *value)
 971 {
 972   struct DirectNeighbor *neighbor = value;
 973
 974   if ( (GNUNET_YES != neighbor->connected) ||
 975        (DIRECT_NEIGHBOR_COST != neighbor->distance) )
 976     return GNUNET_YES;
 977   if (NULL != neighbor->neighbor_table)
 978     GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table,
 979                                            &check_possible_route,
 980                                            neighbor);
 981   return GNUNET_YES;
 982 }
 983
 984
 985 /**
 986  * Task to run #refresh_routes() on all direct neighbours.
 987  *
 988  * @param cls NULL
 989  */
 990 static void
 991 refresh_routes_task (void *cls)
 992 {
 993   rr_task = NULL;
 994   GNUNET_CONTAINER_multipeermap_iterate (direct_neighbors,
 995                                          &refresh_routes,
 996                                          NULL);
 997 }
 998
 999
1000 /**
1001  * Asynchronously run #refresh_routes() at the next opportunity
1002  * on all direct neighbours.
1003  */
1004 static void
1005 schedule_refresh_routes ()
1006 {
1007   if (NULL == rr_task)
1008     rr_task = GNUNET_SCHEDULER_add_now (&refresh_routes_task,
1009                                         NULL);
1010 }
1011
1012
1013 /**
1014  * Multipeermap iterator for freeing routes that go via a particular
1015  * neighbor that disconnected and is thus no longer available.
1016  *
1017  * @param cls the direct neighbor that is now unavailable
1018  * @param key key value stored under
1019  * @param value a `struct Route` that may or may not go via neighbor
1020  *
1021  * @return #GNUNET_YES to continue iteration, #GNUNET_NO to stop
1022  */
1023 static int
1024 cull_routes (void *cls,
1025              const struct GNUNET_PeerIdentity *key,
1026              void *value)
1027 {
1028   struct DirectNeighbor *neighbor = cls;
1029   struct Route *route = value;
1030
1031   if (route->next_hop != neighbor)
1032     return GNUNET_YES; /* not affected */
1033   GNUNET_assert (GNUNET_YES ==
1034                  GNUNET_CONTAINER_multipeermap_remove (all_routes, key, value));
1035   release_route (route);
1036   send_disconnect_to_plugin (&route->target.peer);
1037   GNUNET_free (route);
1038   return GNUNET_YES;
1039 }
1040
1041
1042 /**
1043  * Handle the case that a direct connection to a peer is
1044  * disrupted.  Remove all routes via that peer and
1045  * stop the consensus with it.
1046  *
1047  * @param neighbor peer that was disconnected (or at least is no
1048  *    longer at distance 1)
1049  */
1050 static void
1051 handle_direct_disconnect (struct DirectNeighbor *neighbor)
1052 {
1053   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1054               "Culling routes via %s due to direct disconnect\n",
1055               GNUNET_i2s (&neighbor->peer));
1056   GNUNET_CONTAINER_multipeermap_iterate (all_routes,
1057                                          &cull_routes,
1058                                          neighbor);
1059   if (NULL != neighbor->direct_route)
1060   {
1061     release_route (neighbor->direct_route);
1062     GNUNET_free (neighbor->direct_route);
1063     neighbor->direct_route = NULL;
1064   }
1065   if (NULL != neighbor->neighbor_table_consensus)
1066   {
1067     GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table_consensus,
1068                                            &free_targets,
1069                                            NULL);
1070     GNUNET_CONTAINER_multipeermap_destroy (neighbor->neighbor_table_consensus);
1071     neighbor->neighbor_table_consensus = NULL;
1072   }
1073   if (NULL != neighbor->neighbor_table)
1074   {
1075     GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table,
1076                                            &free_targets,
1077                                            NULL);
1078     GNUNET_CONTAINER_multipeermap_destroy (neighbor->neighbor_table);
1079     neighbor->neighbor_table = NULL;
1080   }
1081   if (NULL != neighbor->set_op)
1082   {
1083     GNUNET_SET_operation_cancel (neighbor->set_op);
1084     neighbor->set_op = NULL;
1085   }
1086   if (NULL != neighbor->my_set)
1087   {
1088     GNUNET_SET_destroy (neighbor->my_set);
1089     neighbor->my_set = NULL;
1090   }
1091   if (NULL != neighbor->listen_handle)
1092   {
1093     GNUNET_SET_listen_cancel (neighbor->listen_handle);
1094     neighbor->listen_handle = NULL;
1095   }
1096   if (NULL != neighbor->initiate_task)
1097   {
1098     GNUNET_SCHEDULER_cancel (neighbor->initiate_task);
1099     neighbor->initiate_task = NULL;
1100   }
1101 }
1102
1103
1104 /**
1105  * Function that is called with QoS information about an address; used
1106  * to update our current distance to another peer.
1107  *
1108  * @param cls closure
1109  * @param address the address
1110  * @param active #GNUNET_YES if this address is actively used
1111  *        to maintain a connection to a peer;
1112  *        #GNUNET_NO if the address is not actively used;
1113  *        #GNUNET_SYSERR if this address is no longer available for ATS
1114  * @param bandwidth_out assigned outbound bandwidth for the connection
1115  * @param bandwidth_in assigned inbound bandwidth for the connection
1116  * @param prop performance data for the address (as far as known)
1117  */
1118 static void
1119 handle_ats_update (void *cls,
1120                    const struct GNUNET_HELLO_Address *address,
1121                    int active,
1122                    struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out,
1123                    struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
1124                    const struct GNUNET_ATS_Properties *prop)
1125 {
1126   struct DirectNeighbor *neighbor;
1127   uint32_t distance;
1128   enum GNUNET_ATS_Network_Type network;
1129
1130   if (NULL == address)
1131   {
1132     /* ATS service temporarily disconnected */
1133     return;
1134   }
1135
1136   if (GNUNET_YES != active)
1137   {
1138     // FIXME: handle disconnect/inactive case too!
1139     return;
1140   }
1141   distance = prop->distance;
1142   network = prop->scope;
1143   GNUNET_break (GNUNET_ATS_NET_UNSPECIFIED != network);
1144   /* check if entry exists */
1145   neighbor = GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
1146                                                 &address->peer);
1147   if (NULL != neighbor)
1148   {
1149     neighbor->network = network;
1150     if (neighbor->distance == distance)
1151       return; /* nothing new to see here, move along */
1152     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1153                 "ATS says distance to %s is now %u\n",
1154                 GNUNET_i2s (&address->peer),
1155                 (unsigned int) distance);
1156     if ( (DIRECT_NEIGHBOR_COST == neighbor->distance) &&
1157          (DIRECT_NEIGHBOR_COST == distance) )
1158       return; /* no change */
1159     if (DIRECT_NEIGHBOR_COST == neighbor->distance)
1160     {
1161       neighbor->distance = distance;
1162       GNUNET_STATISTICS_update (stats,
1163                                 "# peers connected (1-hop)",
1164                                 -1, GNUNET_NO);
1165       handle_direct_disconnect (neighbor);
1166       schedule_refresh_routes ();
1167       return;
1168     }
1169     neighbor->distance = distance;
1170     if (DIRECT_NEIGHBOR_COST != neighbor->distance)
1171       return;
1172     if (GNUNET_YES != neighbor->connected)
1173       return;
1174     handle_direct_connect (neighbor);
1175     return;
1176   }
1177   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1178               "ATS says distance to %s is now %u\n",
1179               GNUNET_i2s (&address->peer),
1180               (unsigned int) distance);
1181   neighbor = GNUNET_new (struct DirectNeighbor);
1182   neighbor->peer = address->peer;
1183   GNUNET_assert (GNUNET_YES ==
1184                  GNUNET_CONTAINER_multipeermap_put (direct_neighbors,
1185                                                     &neighbor->peer,
1186                                                     neighbor,
1187                                                     GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
1188   neighbor->connected = GNUNET_NO; /* not yet */
1189   neighbor->distance = distance;
1190   neighbor->network = network;
1191 }
1192
1193
1194 /**
1195  * Check if a target was removed from the set of the other peer; if so,
1196  * if we also used it for our route, we need to remove it from our
1197  * 'all_routes' set (and later check if an alternative path now exists).
1198  *
1199  * @param cls the `struct DirectNeighbor`
1200  * @param key peer identity for the target
1201  * @param value a `struct Target` previously reachable via the given neighbor
1202  */
1203 static int
1204 check_target_removed (void *cls,
1205                       const struct GNUNET_PeerIdentity *key,
1206                       void *value)
1207 {
1208   struct DirectNeighbor *neighbor = cls;
1209   struct Target *new_target;
1210   struct Route *current_route;
1211
1212   new_target = GNUNET_CONTAINER_multipeermap_get (neighbor->neighbor_table_consensus,
1213                                                   key);
1214   current_route = GNUNET_CONTAINER_multipeermap_get (all_routes,
1215                                                      key);
1216   if (NULL != new_target)
1217   {
1218     /* target was in old set, is in new set */
1219     if ( (NULL != current_route) &&
1220          (current_route->next_hop == neighbor) &&
1221          (current_route->target.distance != new_target->distance) )
1222     {
1223       /* need to recalculate routes due to distance change */
1224       neighbor->target_removed = GNUNET_YES;
1225     }
1226     return GNUNET_OK;
1227   }
1228   /* target was revoked, check if it was used */
1229   if ( (NULL == current_route) ||
1230        (current_route->next_hop != neighbor) )
1231   {
1232     /* didn't matter, wasn't used */
1233     return GNUNET_OK;
1234   }
1235   /* remove existing route */
1236   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1237               "Lost route to %s\n",
1238               GNUNET_i2s (&current_route->target.peer));
1239   GNUNET_assert (GNUNET_YES ==
1240                  GNUNET_CONTAINER_multipeermap_remove (all_routes, key, current_route));
1241   send_disconnect_to_plugin (&current_route->target.peer);
1242   release_route (current_route);
1243   GNUNET_free (current_route);
1244   neighbor->target_removed = GNUNET_YES;
1245   return GNUNET_OK;
1246 }
1247
1248
1249 /**
1250  * Check if a target was added to the set of the other peer; if it
1251  * was added or impoves the existing route, do the needed updates.
1252  *
1253  * @param cls the `struct DirectNeighbor`
1254  * @param key peer identity for the target
1255  * @param value a `struct Target` now reachable via the given neighbor
1256  */
1257 static int
1258 check_target_added (void *cls,
1259                     const struct GNUNET_PeerIdentity *key,
1260                     void *value)
1261 {
1262   struct DirectNeighbor *neighbor = cls;
1263   struct Target *target = value;
1264   struct Route *current_route;
1265
1266   /* target was revoked, check if it was used */
1267   current_route = GNUNET_CONTAINER_multipeermap_get (all_routes,
1268                                                      key);
1269   if (NULL != current_route)
1270   {
1271     /* route exists */
1272     if (current_route->next_hop == neighbor)
1273     {
1274       /* we had the same route before, no change in target */
1275       if (ntohl (target->distance) + 1 != ntohl (current_route->target.distance))
1276       {
1277         /* but distance changed! */
1278         if (ntohl (target->distance) + 1 > DEFAULT_FISHEYE_DEPTH)
1279         {
1280           /* distance increased beyond what is allowed, kill route */
1281           GNUNET_assert (GNUNET_YES ==
1282                          GNUNET_CONTAINER_multipeermap_remove (all_routes,
1283                                                                key,
1284                                                                current_route));
1285           send_disconnect_to_plugin (key);
1286           release_route (current_route);
1287           GNUNET_free (current_route);
1288         }
1289         else
1290         {
1291           /* distance decreased, update route */
1292           move_route (current_route,
1293                       ntohl (target->distance) + 1);
1294           send_distance_change_to_plugin (&target->peer,
1295                                           ntohl (target->distance) + 1,
1296                                           neighbor->network);
1297         }
1298       }
1299       return GNUNET_OK;
1300     }
1301     if (ntohl (current_route->target.distance) <= ntohl (target->distance) + 1)
1302     {
1303       /* alternative, shorter route exists, ignore */
1304       return GNUNET_OK;
1305     }
1306     /* new route is better than the existing one, take over! */
1307     /* NOTE: minor security issue: malicious peers may advertise
1308        very short routes to take over longer paths; as we don't
1309        check that the shorter routes actually work, a malicious
1310        direct neighbor can use this to DoS our long routes */
1311
1312     move_route (current_route, ntohl (target->distance) + 1);
1313     current_route->next_hop = neighbor;
1314     send_distance_change_to_plugin (&target->peer,
1315                                     ntohl (target->distance) + 1,
1316                                     neighbor->network);
1317     return GNUNET_OK;
1318   }
1319   /* new route */
1320   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1321               "Discovered new route to %s using %u hops\n",
1322               GNUNET_i2s (&target->peer),
1323               (unsigned int) (ntohl (target->distance) + 1));
1324   current_route = GNUNET_new (struct Route);
1325   current_route->next_hop = neighbor;
1326   current_route->target.peer = target->peer;
1327   allocate_route (current_route, ntohl (target->distance) + 1);
1328   GNUNET_assert (GNUNET_YES ==
1329                  GNUNET_CONTAINER_multipeermap_put (all_routes,
1330                                                     &current_route->target.peer,
1331                                                     current_route,
1332                                                     GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
1333
1334   send_connect_to_plugin (&current_route->target.peer,
1335                           ntohl (current_route->target.distance),
1336                           neighbor->network);
1337   return GNUNET_OK;
1338 }
1339
1340
1341 /**
1342  * Callback for set operation results. Called for each element
1343  * in the result set.
1344  * We have learned a new route from the other peer.  Add it to the
1345  * route set we're building.
1346  *
1347  * @param cls the `struct DirectNeighbor` we're building the consensus with
1348  * @param element a result element, only valid if status is #GNUNET_SET_STATUS_OK
1349  * @param current_size current set size
1350  * @param status see `enum GNUNET_SET_Status`
1351  */
1352 static void
1353 handle_set_union_result (void *cls,
1354                          const struct GNUNET_SET_Element *element,
1355                          uint64_t current_size,
1356                          enum GNUNET_SET_Status status)
1357 {
1358   struct DirectNeighbor *neighbor = cls;
1359   struct DirectNeighbor *dn;
1360   struct Target *target;
1361   const struct Target *ctarget;
1362   char *status_str;
1363
1364   switch (status)
1365   {
1366   case GNUNET_SET_STATUS_OK:
1367     status_str = "GNUNET_SET_STATUS_OK";
1368     break;
1369   case GNUNET_SET_STATUS_FAILURE:
1370     status_str = "GNUNET_SET_STATUS_FAILURE";
1371     break;
1372   case GNUNET_SET_STATUS_HALF_DONE:
1373     status_str = "GNUNET_SET_STATUS_HALF_DONE";
1374     break;
1375   case GNUNET_SET_STATUS_DONE:
1376     status_str = "GNUNET_SET_STATUS_DONE";
1377     break;
1378   default:
1379     status_str = "UNDEFINED";
1380     break;
1381   }
1382
1383   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1384               "Got SET union result: %s\n",
1385               status_str);
1386   switch (status)
1387   {
1388   case GNUNET_SET_STATUS_OK:
1389     if (sizeof (struct Target) != element->size)
1390     {
1391       GNUNET_break_op (0);
1392       return;
1393     }
1394     ctarget = element->data;
1395     if ( (NULL !=
1396           (dn = GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
1397                                                    &ctarget->peer))) &&
1398          (DIRECT_NEIGHBOR_COST == dn->distance) )
1399     {
1400       /* this is a direct neighbor of ours, we do not care about routes
1401          to this peer */
1402       return;
1403     }
1404     target = GNUNET_new (struct Target);
1405     GNUNET_memcpy (target, element->data, sizeof (struct Target));
1406     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1407                 "Received information about peer `%s' with distance %u from SET\n",
1408                 GNUNET_i2s (&target->peer),
1409                 ntohl (target->distance) + 1);
1410
1411     if (NULL == neighbor->neighbor_table_consensus)
1412       neighbor->neighbor_table_consensus
1413         = GNUNET_CONTAINER_multipeermap_create (10, GNUNET_NO);
1414     if (GNUNET_YES !=
1415         GNUNET_CONTAINER_multipeermap_put (neighbor->neighbor_table_consensus,
1416                                            &target->peer,
1417                                            target,
1418                                            GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
1419     {
1420       GNUNET_break_op (0);
1421       GNUNET_free (target);
1422     }
1423     break;
1424   case GNUNET_SET_STATUS_FAILURE:
1425     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1426                 "Failed to establish DV union, will try again later\n");
1427     neighbor->set_op = NULL;
1428     if (NULL != neighbor->neighbor_table_consensus)
1429     {
1430       GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table_consensus,
1431                                              &free_targets,
1432                                              NULL);
1433       GNUNET_CONTAINER_multipeermap_destroy (neighbor->neighbor_table_consensus);
1434       neighbor->neighbor_table_consensus = NULL;
1435     }
1436     if (0 < memcmp (&neighbor->peer,
1437                     &my_identity,
1438                     sizeof (struct GNUNET_PeerIdentity)))
1439       neighbor->initiate_task = GNUNET_SCHEDULER_add_delayed (GNUNET_DV_CONSENSUS_FREQUENCY,
1440                                                               &initiate_set_union,
1441                                                               neighbor);
1442     break;
1443   case GNUNET_SET_STATUS_HALF_DONE:
1444     break;
1445   case GNUNET_SET_STATUS_DONE:
1446     /* we got all of our updates; integrate routing table! */
1447     neighbor->target_removed = GNUNET_NO;
1448     if (NULL == neighbor->neighbor_table_consensus)
1449       neighbor->neighbor_table_consensus = GNUNET_CONTAINER_multipeermap_create (10, GNUNET_NO);
1450     if (NULL != neighbor->neighbor_table)
1451       GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table,
1452                                              &check_target_removed,
1453                                              neighbor);
1454     if (GNUNET_YES == neighbor->target_removed)
1455     {
1456       /* check if we got an alternative for the removed routes */
1457       schedule_refresh_routes ();
1458     }
1459     /* add targets that appeared (and check for improved routes) */
1460     GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table_consensus,
1461                                            &check_target_added,
1462                                            neighbor);
1463     if (NULL != neighbor->neighbor_table)
1464     {
1465       GNUNET_CONTAINER_multipeermap_iterate (neighbor->neighbor_table,
1466                                              &free_targets,
1467                                              NULL);
1468       GNUNET_CONTAINER_multipeermap_destroy (neighbor->neighbor_table);
1469       neighbor->neighbor_table = NULL;
1470     }
1471     neighbor->neighbor_table = neighbor->neighbor_table_consensus;
1472     neighbor->neighbor_table_consensus = NULL;
1473
1474     /* operation done, schedule next run! */
1475     neighbor->set_op = NULL;
1476     if (0 < memcmp (&neighbor->peer,
1477                     &my_identity,
1478                     sizeof (struct GNUNET_PeerIdentity)))
1479       neighbor->initiate_task = GNUNET_SCHEDULER_add_delayed (GNUNET_DV_CONSENSUS_FREQUENCY,
1480                                                               &initiate_set_union,
1481                                                               neighbor);
1482     break;
1483   default:
1484     GNUNET_break (0);
1485     return;
1486   }
1487 }
1488
1489
1490 /**
1491  * Start creating a new DV set union construction, our neighbour has
1492  * asked for it (callback for listening peer).
1493  *
1494  * @param cls the 'struct DirectNeighbor' of the peer we're building
1495  *        a routing consensus with
1496  * @param other_peer the other peer
1497  * @param context_msg message with application specific information from
1498  *        the other peer
1499  * @param request request from the other peer, use GNUNET_SET_accept
1500  *        to accept it, otherwise the request will be refused
1501  *        Note that we don't use a return value here, as it is also
1502  *        necessary to specify the set we want to do the operation with,
1503  *        whith sometimes can be derived from the context message.
1504  *        Also necessary to specify the timeout.
1505  */
1506 static void
1507 listen_set_union (void *cls,
1508                   const struct GNUNET_PeerIdentity *other_peer,
1509                   const struct GNUNET_MessageHeader *context_msg,
1510                   struct GNUNET_SET_Request *request)
1511 {
1512   struct DirectNeighbor *neighbor = cls;
1513
1514   if (NULL == request)
1515     return; /* why??? */
1516   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1517               "Starting to create consensus with %s\n",
1518               GNUNET_i2s (&neighbor->peer));
1519   if (NULL != neighbor->set_op)
1520   {
1521     GNUNET_SET_operation_cancel (neighbor->set_op);
1522     neighbor->set_op = NULL;
1523   }
1524   if (NULL != neighbor->my_set)
1525   {
1526     GNUNET_SET_destroy (neighbor->my_set);
1527     neighbor->my_set = NULL;
1528   }
1529   neighbor->my_set = GNUNET_SET_create (cfg,
1530                                         GNUNET_SET_OPERATION_UNION);
1531   neighbor->set_op = GNUNET_SET_accept (request,
1532                                         GNUNET_SET_RESULT_ADDED,
1533                                         (struct GNUNET_SET_Option[]) { 0 },
1534                                         &handle_set_union_result,
1535                                         neighbor);
1536   neighbor->consensus_insertion_offset = 0;
1537   neighbor->consensus_insertion_distance = 0;
1538   neighbor->consensus_elements = 0;
1539   build_set (neighbor);
1540 }
1541
1542
1543 /**
1544  * Start creating a new DV set union by initiating the connection.
1545  *
1546  * @param cls the `struct DirectNeighbor *` of the peer we're building
1547  *        a routing consensus with
1548  */
1549 static void
1550 initiate_set_union (void *cls)
1551 {
1552   struct DirectNeighbor *neighbor = cls;
1553
1554   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1555               "Initiating SET union with peer `%s'\n",
1556               GNUNET_i2s (&neighbor->peer));
1557   neighbor->initiate_task = NULL;
1558   neighbor->my_set = GNUNET_SET_create (cfg,
1559                                         GNUNET_SET_OPERATION_UNION);
1560   neighbor->set_op = GNUNET_SET_prepare (&neighbor->peer,
1561                                          &neighbor->real_session_id,
1562                                          NULL,
1563                                          GNUNET_SET_RESULT_ADDED,
1564                                          (struct GNUNET_SET_Option[]) { 0 },
1565                                          &handle_set_union_result,
1566                                          neighbor);
1567   neighbor->consensus_insertion_offset = 0;
1568   neighbor->consensus_insertion_distance = 0;
1569   neighbor->consensus_elements = 0;
1570   build_set (neighbor);
1571 }
1572
1573
1574 /**
1575  * Check that @a rm is well-formed.
1576  *
1577  * @param cls closure
1578  * @param rm the message
1579  * @return #GNUNET_OK if @a rm is well-formed.
1580  */
1581 static int
1582 check_dv_route_message (void *cls,
1583                         const struct RouteMessage *rm)
1584 {
1585   const struct GNUNET_MessageHeader *payload;
1586
1587   if (ntohs (rm->header.size) < sizeof (struct RouteMessage) + sizeof (struct GNUNET_MessageHeader))
1588   {
1589     GNUNET_break_op (0);
1590     return GNUNET_SYSERR;
1591   }
1592   payload = (const struct GNUNET_MessageHeader *) &rm[1];
1593   if (ntohs (rm->header.size) != sizeof (struct RouteMessage) + ntohs (payload->size))
1594   {
1595     GNUNET_break_op (0);
1596     return GNUNET_SYSERR;
1597   }
1598   return GNUNET_OK;
1599 }
1600
1601
1602 /**
1603  * Core handler for DV data messages.  Whatever this message
1604  * contains all we really have to do is rip it out of its
1605  * DV layering and give it to our pal the DV plugin to report
1606  * in with.
1607  *
1608  * @param cls closure
1609  * @param rm the message
1610  */
1611 static void
1612 handle_dv_route_message (void *cls,
1613                          const struct RouteMessage *rm)
1614 {
1615   struct DirectNeighbor *neighbor = cls;
1616   const struct GNUNET_MessageHeader *payload;
1617   struct Route *route;
1618   struct DirectNeighbor *nneighbor;
1619   struct DirectNeighbor *dn;
1620   struct Target *target;
1621   uint32_t distance;
1622   char me[5];
1623   char src[5];
1624   char prev[5];
1625   char dst[5];
1626
1627   distance = ntohl (rm->distance);
1628   payload = (const struct GNUNET_MessageHeader *) &rm[1];
1629   strncpy (prev, GNUNET_i2s (&neighbor->peer), 4);
1630   strncpy (me, GNUNET_i2s (&my_identity), 4);
1631   strncpy (src, GNUNET_i2s (&rm->sender), 4);
1632   strncpy (dst, GNUNET_i2s (&rm->target), 4);
1633   prev[4] = me[4] = src[4] = dst[4] = '\0';
1634   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1635               "Handling DV message with %u bytes payload of type %u from %s to %s routed by %s to me (%s @ hop %u)\n",
1636               (unsigned int) (ntohs (rm->header.size) - sizeof (struct RouteMessage)),
1637               ntohs (payload->type),
1638               src,
1639               dst,
1640               prev,
1641               me,
1642               (unsigned int) distance + 1);
1643
1644   if (0 == memcmp (&rm->target,
1645                    &my_identity,
1646                    sizeof (struct GNUNET_PeerIdentity)))
1647   {
1648     if ((NULL !=
1649          (dn = GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
1650                                                   &rm->sender))) &&
1651         (DIRECT_NEIGHBOR_COST == dn->distance))
1652     {
1653       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1654                   "Discarding DV message, as %s is a direct neighbor\n",
1655                   GNUNET_i2s (&rm->sender));
1656       GNUNET_STATISTICS_update (stats,
1657                                 "# messages discarded (direct neighbor)",
1658                                 1, GNUNET_NO);
1659       return;
1660     }
1661     /* message is for me, check reverse route! */
1662     route = GNUNET_CONTAINER_multipeermap_get (all_routes,
1663                                                &rm->sender);
1664     if ( (NULL == route) &&
1665          (distance < DEFAULT_FISHEYE_DEPTH) )
1666     {
1667       /* don't have reverse route yet, learn it! */
1668       target = GNUNET_new (struct Target);
1669       target->peer = rm->sender;
1670       target->distance = htonl (distance);
1671       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1672                   "Learning sender %s at distance %u from delivery!\n",
1673                   GNUNET_i2s (&rm->sender),
1674                   (unsigned int) distance + 1);
1675       if (NULL == neighbor->neighbor_table)
1676         neighbor->neighbor_table = GNUNET_CONTAINER_multipeermap_create (10, GNUNET_NO);
1677       if (GNUNET_YES !=
1678           GNUNET_CONTAINER_multipeermap_put (neighbor->neighbor_table,
1679                                              &target->peer,
1680                                              target,
1681                                              GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
1682       {
1683         GNUNET_break_op (0);
1684         GNUNET_free (target);
1685         return;
1686       }
1687       add_new_route (target, neighbor);
1688     }
1689     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1690                 "Delivering %u bytes from %s to myself!\n",
1691                 ntohs (payload->size),
1692                 GNUNET_i2s (&rm->sender));
1693     send_data_to_plugin (payload,
1694                          &rm->sender,
1695                          1 + distance);
1696     return;
1697   }
1698   if ( (NULL == GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
1699                                                    &rm->sender)) &&
1700        (NULL == GNUNET_CONTAINER_multipeermap_get (all_routes,
1701                                                    &rm->sender)) )
1702   {
1703     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1704                 "Learning sender %s at distance %u from forwarding!\n",
1705                 GNUNET_i2s (&rm->sender),
1706                 1 + distance);
1707     target = GNUNET_new (struct Target);
1708     target->peer = rm->sender;
1709     target->distance = htonl (distance);
1710     if (NULL == neighbor->neighbor_table)
1711       neighbor->neighbor_table = GNUNET_CONTAINER_multipeermap_create (10, GNUNET_NO);
1712     if (GNUNET_YES !=
1713         GNUNET_CONTAINER_multipeermap_put (neighbor->neighbor_table,
1714                                            &target->peer,
1715                                            target,
1716                                            GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
1717     {
1718       GNUNET_break_op (0);
1719       GNUNET_free (target);
1720       return;
1721     }
1722     add_new_route (target, neighbor);
1723   }
1724
1725   route = GNUNET_CONTAINER_multipeermap_get (all_routes,
1726                                              &rm->target);
1727   if (NULL == route)
1728   {
1729     nneighbor = GNUNET_CONTAINER_multipeermap_get (direct_neighbors,
1730                                                   &rm->target);
1731     if (NULL == nneighbor)
1732     {
1733       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1734                   "No route to %s, not routing %u bytes!\n",
1735                   GNUNET_i2s (&rm->target),
1736                   ntohs (payload->size));
1737       GNUNET_STATISTICS_update (stats,
1738                                 "# messages discarded (no route)",
1739                                 1, GNUNET_NO);
1740       return;
1741     }
1742   }
1743   else
1744   {
1745     nneighbor = route->next_hop;
1746   }
1747   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1748               "Forwarding message to %s\n",
1749               GNUNET_i2s (&nneighbor->peer));
1750   forward_payload (nneighbor,
1751                    distance + 1,
1752                    &rm->sender,
1753                    &rm->target,
1754                    payload);
1755 }
1756
1757
1758 /**
1759  * Check that @a msg is well-formed
1760  *
1761  * @param cls identification of the client
1762  * @param message the actual message
1763  * @return #GNUNET_OK if @a msg is well-formed
1764  */
1765 static int
1766 check_dv_send_message (void *cls,
1767                        const struct GNUNET_DV_SendMessage *msg)
1768 {
1769   const struct GNUNET_MessageHeader *payload;
1770
1771   if (ntohs (msg->header.size) < sizeof (struct GNUNET_DV_SendMessage) +
1772       sizeof (struct GNUNET_MessageHeader))
1773   {
1774     GNUNET_break (0);
1775     return GNUNET_SYSERR;
1776   }
1777   payload = (const struct GNUNET_MessageHeader *) &msg[1];
1778   if (ntohs (msg->header.size) != sizeof (struct GNUNET_DV_SendMessage) + ntohs (payload->size))
1779   {
1780     GNUNET_break (0);
1781     return GNUNET_SYSERR;
1782   }
1783   return GNUNET_OK;
1784 }
1785
1786
1787 /**
1788  * Service server's handler for message send requests (which come
1789  * bubbling up to us through the DV plugin).
1790  *
1791  * @param cls identification of the client
1792  * @param message the actual message
1793  */
1794 static void
1795 handle_dv_send_message (void *cls,
1796                         const struct GNUNET_DV_SendMessage *msg)
1797 {
1798   struct GNUNET_SERVICE_Client *client = cls;
1799   struct Route *route;
1800   const struct GNUNET_MessageHeader *payload;
1801
1802   payload = (const struct GNUNET_MessageHeader *) &msg[1];
1803   route = GNUNET_CONTAINER_multipeermap_get (all_routes,
1804                                              &msg->target);
1805   if (NULL == route)
1806   {
1807     /* got disconnected */
1808     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1809                 "No route to %s, dropping local message of type %u\n",
1810                 GNUNET_i2s (&msg->target),
1811                 ntohs (payload->type));
1812     GNUNET_STATISTICS_update (stats,
1813                               "# local messages discarded (no route)",
1814                               1, GNUNET_NO);
1815     GNUNET_SERVICE_client_continue (client);
1816     return;
1817   }
1818   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1819               "Forwarding %u bytes of type %u to %s\n",
1820               ntohs (payload->size),
1821               ntohs (payload->type),
1822               GNUNET_i2s (&msg->target));
1823
1824   forward_payload (route->next_hop,
1825                    0 /* first hop, distance is zero */,
1826                    &my_identity,
1827                    &msg->target,
1828                    payload);
1829   GNUNET_SERVICE_client_continue (client);
1830 }
1831
1832
1833 /**
1834  * Cleanup all of the data structures associated with a given neighbor.
1835  *
1836  * @param neighbor neighbor to clean up
1837  */
1838 static void
1839 cleanup_neighbor (struct DirectNeighbor *neighbor)
1840 {
1841   handle_direct_disconnect (neighbor);
1842   GNUNET_assert (GNUNET_YES ==
1843                  GNUNET_CONTAINER_multipeermap_remove (direct_neighbors,
1844                                                        &neighbor->peer,
1845                                                        neighbor));
1846   GNUNET_free (neighbor);
1847 }
1848
1849
1850 /**
1851  * Method called whenever a given peer disconnects.
1852  *
1853  * @param cls closure
1854  * @param peer peer identity this notification is about
1855  * @param internal_cls the corresponding `struct DirectNeighbor`
1856  */
1857 static void
1858 handle_core_disconnect (void *cls,
1859                         const struct GNUNET_PeerIdentity *peer,
1860                         void *internal_cls)
1861 {
1862   struct DirectNeighbor *neighbor = internal_cls;
1863
1864   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1865               "Received core peer disconnect message for peer `%s'!\n",
1866               GNUNET_i2s (peer));
1867   /* Check for disconnect from self message */
1868   if (NULL == neighbor)
1869     return;
1870   GNUNET_break (GNUNET_YES == neighbor->connected);
1871   neighbor->connected = GNUNET_NO;
1872   if (DIRECT_NEIGHBOR_COST == neighbor->distance)
1873   {
1874     GNUNET_STATISTICS_update (stats,
1875                               "# peers connected (1-hop)",
1876                               -1,
1877                               GNUNET_NO);
1878   }
1879   cleanup_neighbor (neighbor);
1880   if (GNUNET_YES == in_shutdown)
1881     return;
1882   schedule_refresh_routes ();
1883 }
1884
1885
1886 /**
1887  * Multipeermap iterator for freeing routes.  Should never be called.
1888  *
1889  * @param cls NULL
1890  * @param key key value stored under
1891  * @param value the route to be freed
1892  * @return #GNUNET_YES to continue iteration, #GNUNET_NO to stop
1893  */
1894 static int
1895 free_route (void *cls,
1896             const struct GNUNET_PeerIdentity *key,
1897             void *value)
1898 {
1899   struct Route *route = value;
1900
1901   GNUNET_break (0);
1902   GNUNET_assert (GNUNET_YES ==
1903                  GNUNET_CONTAINER_multipeermap_remove (all_routes, key, value));
1904   release_route (route);
1905   send_disconnect_to_plugin (&route->target.peer);
1906   GNUNET_free (route);
1907   return GNUNET_YES;
1908 }
1909
1910
1911 /**
1912  * Multipeermap iterator for freeing direct neighbors. Should never be called.
1913  *
1914  * @param cls NULL
1915  * @param key key value stored under
1916  * @param value the direct neighbor to be freed
1917  * @return #GNUNET_YES to continue iteration, #GNUNET_NO to stop
1918  */
1919 static int
1920 free_direct_neighbors (void *cls,
1921                        const struct GNUNET_PeerIdentity *key,
1922                        void *value)
1923 {
1924   struct DirectNeighbor *neighbor = value;
1925
1926   cleanup_neighbor (neighbor);
1927   return GNUNET_YES;
1928 }
1929
1930
1931 /**
1932  * Task run during shutdown.
1933  *
1934  * @param cls unused
1935  */
1936 static void
1937 shutdown_task (void *cls)
1938 {
1939   unsigned int i;
1940
1941   in_shutdown = GNUNET_YES;
1942   GNUNET_assert (NULL != core_api);
1943   GNUNET_CORE_disconnect (core_api);
1944   core_api = NULL;
1945   GNUNET_ATS_performance_done (ats);
1946   ats = NULL;
1947   GNUNET_CONTAINER_multipeermap_iterate (direct_neighbors,
1948                                          &free_direct_neighbors,
1949                                          NULL);
1950   GNUNET_CONTAINER_multipeermap_iterate (all_routes,
1951                                          &free_route,
1952                                          NULL);
1953   GNUNET_CONTAINER_multipeermap_destroy (direct_neighbors);
1954   GNUNET_CONTAINER_multipeermap_destroy (all_routes);
1955   GNUNET_STATISTICS_destroy (stats, GNUNET_NO);
1956   stats = NULL;
1957   GNUNET_notification_context_destroy (nc);
1958   nc = NULL;
1959   for (i=0;i<DEFAULT_FISHEYE_DEPTH;i++)
1960   {
1961     GNUNET_array_grow (consensi[i].targets,
1962                        consensi[i].array_length,
1963                        0);
1964   }
1965   if (NULL != rr_task)
1966   {
1967     GNUNET_SCHEDULER_cancel (rr_task);
1968     rr_task = NULL;
1969   }
1970 }
1971
1972
1973 /**
1974  * Notify newly connected client about an existing route.
1975  *
1976  * @param cls the `struct GNUNET_SERVICE_Client *`
1977  * @param key peer identity
1978  * @param value the `struct Route *`
1979  * @return #GNUNET_OK (continue to iterate)
1980  */
1981 static int
1982 notify_client_about_route (void *cls,
1983                            const struct GNUNET_PeerIdentity *key,
1984                            void *value)
1985 {
1986   struct GNUNET_SERVICE_Client *client = cls;
1987   struct Route *route = value;
1988   struct GNUNET_MQ_Envelope *env;
1989   struct GNUNET_DV_ConnectMessage *cm;
1990
1991   env = GNUNET_MQ_msg (cm,
1992                        GNUNET_MESSAGE_TYPE_DV_CONNECT);
1993   cm->distance = htonl (route->target.distance);
1994   cm->peer = route->target.peer;
1995   GNUNET_MQ_send (GNUNET_SERVICE_client_get_mq (client),
1996                   env);
1997   return GNUNET_OK;
1998 }
1999
2000
2001 /**
2002  * Handle START-message.  This is the first message sent to us
2003  * by the client (can only be one!).
2004  *
2005  * @param cls closure (always NULL)
2006  * @param client identification of the client
2007  * @param message the actual message
2008  */
2009 static void
2010 handle_start (void *cls,
2011               const struct GNUNET_MessageHeader *message)
2012 {
2013   struct GNUNET_SERVICE_Client *client = cls;
2014
2015   GNUNET_notification_context_add (nc,
2016                                    GNUNET_SERVICE_client_get_mq (client));
2017   GNUNET_SERVICE_client_continue (client);
2018   GNUNET_CONTAINER_multipeermap_iterate (all_routes,
2019                                          &notify_client_about_route,
2020                                          client);
2021 }
2022
2023
2024 /**
2025  * Called on core init.
2026  *
2027  * @param cls unused
2028  * @param identity this peer's identity
2029  */
2030 static void
2031 core_init (void *cls,
2032            const struct GNUNET_PeerIdentity *identity)
2033 {
2034   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2035               "I am peer: %s\n",
2036               GNUNET_i2s (identity));
2037   my_identity = *identity;
2038 }
2039
2040
2041 /**
2042  * Process dv requests.
2043  *
2044  * @param cls closure
2045  * @param c configuration to use
2046  * @param service the initialized service
2047  */
2048 static void
2049 run (void *cls,
2050      const struct GNUNET_CONFIGURATION_Handle *c,
2051      struct GNUNET_SERVICE_Handle *service)
2052 {
2053   struct GNUNET_MQ_MessageHandler core_handlers[] = {
2054     GNUNET_MQ_hd_var_size (dv_route_message,
2055                            GNUNET_MESSAGE_TYPE_DV_ROUTE,
2056                            struct RouteMessage,
2057                            NULL),
2058     GNUNET_MQ_handler_end ()
2059   };
2060   in_shutdown = GNUNET_NO;
2061   cfg = c;
2062   direct_neighbors = GNUNET_CONTAINER_multipeermap_create (128,
2063                                                            GNUNET_NO);
2064   all_routes = GNUNET_CONTAINER_multipeermap_create (65536,
2065                                                      GNUNET_NO);
2066   core_api = GNUNET_CORE_connect (cfg,
2067                                   NULL,
2068                                   &core_init,
2069                                   &handle_core_connect,
2070                                   &handle_core_disconnect,
2071                                   core_handlers);
2072
2073   if (NULL == core_api)
2074     return;
2075   ats = GNUNET_ATS_performance_init (cfg,
2076                                      &handle_ats_update,
2077                                      NULL);
2078   if (NULL == ats)
2079   {
2080     GNUNET_CORE_disconnect (core_api);
2081     core_api = NULL;
2082     return;
2083   }
2084   nc = GNUNET_notification_context_create (MAX_QUEUE_SIZE_PLUGIN);
2085   stats = GNUNET_STATISTICS_create ("dv",
2086                                     cfg);
2087   GNUNET_SCHEDULER_add_shutdown (&shutdown_task,
2088                                  NULL);
2089 }
2090
2091
2092 /**
2093  * Callback called when a client connects to the service.
2094  *
2095  * @param cls closure for the service
2096  * @param c the new client that connected to the service
2097  * @param mq the message queue used to send messages to the client
2098  * @return @a c
2099  */
2100 static void *
2101 client_connect_cb (void *cls,
2102                    struct GNUNET_SERVICE_Client *c,
2103                    struct GNUNET_MQ_Handle *mq)
2104 {
2105   return c;
2106 }
2107
2108
2109 /**
2110  * Callback called when a client disconnected from the service
2111  *
2112  * @param cls closure for the service
2113  * @param c the client that disconnected
2114  * @param internal_cls should be equal to @a c
2115  */
2116 static void
2117 client_disconnect_cb (void *cls,
2118                       struct GNUNET_SERVICE_Client *c,
2119                       void *internal_cls)
2120 {
2121   GNUNET_assert (c == internal_cls);
2122 }
2123
2124
2125 /**
2126  * Define "main" method using service macro.
2127  */
2128 GNUNET_SERVICE_MAIN
2129 ("dv",
2130  GNUNET_SERVICE_OPTION_NONE,
2131  &run,
2132  &client_connect_cb,
2133  &client_disconnect_cb,
2134  NULL,
2135  GNUNET_MQ_hd_fixed_size (start,
2136                           GNUNET_MESSAGE_TYPE_DV_START,
2137                           struct GNUNET_MessageHeader,
2138                           NULL),
2139  GNUNET_MQ_hd_var_size (dv_send_message,
2140                         GNUNET_MESSAGE_TYPE_DV_SEND,
2141                         struct GNUNET_DV_SendMessage,
2142                         NULL),
2143  GNUNET_MQ_handler_end ());
2144
2145
2146 /* end of gnunet-service-dv.c */