2 This file is part of GNUnet.
3 (C) 2013 Christian Grothoff (and other contributing authors)
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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
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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
27 * @author Christian Grothoff
28 * @author Nathan Evans
31 * - distance updates are not properly communicate to US by core/transport/ats
34 #include "gnunet_util_lib.h"
35 #include "gnunet_protocols.h"
36 #include "gnunet_core_service.h"
37 #include "gnunet_hello_lib.h"
38 #include "gnunet_peerinfo_service.h"
39 #include "gnunet_statistics_service.h"
40 #include "gnunet_consensus_service.h"
45 * How often do we establish the consensu?
47 #define GNUNET_DV_CONSENSUS_FREQUENCY GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 5)
50 * Maximum number of messages we queue per peer.
52 #define MAX_QUEUE_SIZE 16
55 * Maximum number of messages we queue towards the clients/plugin.
57 #define MAX_QUEUE_SIZE_PLUGIN 1024
60 * The default fisheye depth, from how many hops away will
63 #define DEFAULT_FISHEYE_DEPTH 3
66 * How many hops is a direct neighbor away?
68 #define DIRECT_NEIGHBOR_COST 1
71 GNUNET_NETWORK_STRUCT_BEGIN
74 * Information about a peer DV can route to. These entries are what
75 * we use as the binary format to establish consensus to create our
76 * routing table and as the address format in the HELLOs.
82 * Identity of the peer we can reach.
84 struct GNUNET_PeerIdentity peer;
87 * How many hops (1-3) is this peer away? in network byte order
89 uint32_t distance GNUNET_PACKED;
95 * Message exchanged between DV services (via core), requesting a
96 * message to be routed.
101 * Type: GNUNET_MESSAGE_TYPE_DV_ROUTE
103 struct GNUNET_MessageHeader header;
106 * Expected (remaining) distance. Must be always smaller than
107 * DEFAULT_FISHEYE_DEPTH, should be zero at the target. Must
108 * be decremented by one at each hop. Peers must not forward
109 * these messages further once the counter has reached zero.
111 uint32_t distance GNUNET_PACKED;
114 * The (actual) target of the message (this peer, if distance is zero).
116 struct GNUNET_PeerIdentity target;
119 * The (actual) sender of the message.
121 struct GNUNET_PeerIdentity sender;
125 GNUNET_NETWORK_STRUCT_END
129 * Linked list of messages to send to clients.
131 struct PendingMessage
134 * Pointer to next item in the list
136 struct PendingMessage *next;
139 * Pointer to previous item in the list
141 struct PendingMessage *prev;
144 * Actual message to be sent, allocated after this struct.
146 const struct GNUNET_MessageHeader *msg;
149 * Ultimate target for the message.
151 struct GNUNET_PeerIdentity ultimate_target;
154 * Unique ID of the message.
162 * Information about a direct neighbor (core-level, excluding
163 * DV-links, only DV-enabled peers).
165 struct DirectNeighbor
169 * Identity of the peer.
171 struct GNUNET_PeerIdentity peer;
174 * Head of linked list of messages to send to this peer.
176 struct PendingMessage *pm_head;
179 * Tail of linked list of messages to send to this peer.
181 struct PendingMessage *pm_tail;
184 * Transmit handle to core service.
186 struct GNUNET_CORE_TransmitHandle *cth;
189 * Routing table of the neighbor, NULL if not yet established.
190 * Keys are peer identities, values are 'struct Target' entries.
191 * Note that the distances in the targets are from the point-of-view
192 * of the peer, not from us!
194 struct GNUNET_CONTAINER_MultiHashMap *neighbor_table;
197 * Updated routing table of the neighbor, under construction,
198 * NULL if we are not currently building it.
199 * Keys are peer identities, values are 'struct Target' entries.
200 * Note that the distances in the targets are from the point-of-view
201 * of the peer, not from us!
203 struct GNUNET_CONTAINER_MultiHashMap *neighbor_table_consensus;
206 * Active consensus, if we are currently synchronizing the
209 struct GNUNET_CONSENSUS_Handle *consensus;
212 * ID of the task we use to (periodically) update our consensus
215 GNUNET_SCHEDULER_TaskIdentifier consensus_task;
218 * At what offset are we, with respect to inserting our own routes
219 * into the consensus?
221 unsigned int consensus_insertion_offset;
224 * At what distance are we, with respect to inserting our own routes
225 * into the consensus?
227 unsigned int consensus_insertion_distance;
230 * Number of messages currently in the 'pm_XXXX'-DLL.
232 unsigned int pm_queue_size;
235 * Flag set within 'check_target_removed' to trigger full global route refresh.
243 * A route includes information about the next hop,
244 * the target, and the ultimate distance to the
251 * Which peer do we need to forward the message to?
253 struct DirectNeighbor *next_hop;
256 * What would be the target, and how far is it away?
258 struct Target target;
261 * Offset of this target in the respective consensus set.
263 unsigned int set_offset;
269 * Set of targets we bring to a consensus; all targets in a set have a
270 * distance equal to the sets distance (which is implied by the array
277 * Array of targets in the set, may include NULL entries if a
278 * neighbor has disconnected; the targets are allocated with the
279 * respective container (all_routes), not here.
281 struct Route **targets;
284 * Size of the 'targets' array.
286 unsigned int array_length;
292 * Hashmap of all of our direct neighbors (no DV routing).
294 static struct GNUNET_CONTAINER_MultiHashMap *direct_neighbors;
297 * Hashmap with all routes that we currently support; contains
298 * routing information for all peers from distance 2
299 * up to distance DEFAULT_FISHEYE_DEPTH.
301 static struct GNUNET_CONTAINER_MultiHashMap *all_routes;
304 * Array of consensus sets we expose to the outside world. Sets
305 * are structured by the distance to the target.
307 static struct ConsensusSet consensi[DEFAULT_FISHEYE_DEPTH - 1];
310 * Handle to the core service api.
312 static struct GNUNET_CORE_Handle *core_api;
315 * The identity of our peer.
317 static struct GNUNET_PeerIdentity my_identity;
320 * The configuration for this service.
322 static const struct GNUNET_CONFIGURATION_Handle *cfg;
325 * The client, the DV plugin connected to us (or an event monitor).
326 * Hopefully this client will never change, although if the plugin
327 * dies and returns for some reason it may happen.
329 static struct GNUNET_SERVER_NotificationContext *nc;
332 * Handle for the statistics service.
334 struct GNUNET_STATISTICS_Handle *stats;
338 * Get distance information from 'atsi'.
340 * @param atsi performance data
341 * @param atsi_count number of entries in atsi
342 * @return connected transport distance
345 get_atsi_distance (const struct GNUNET_ATS_Information *atsi,
346 unsigned int atsi_count)
350 for (i = 0; i < atsi_count; i++)
351 if (ntohl (atsi[i].type) == GNUNET_ATS_QUALITY_NET_DISTANCE)
352 return ntohl (atsi->value);
353 /* FIXME: we do not have distance data? Assume direct neighbor. */
354 return DIRECT_NEIGHBOR_COST;
359 * Forward a message from another peer to the plugin.
361 * @param message the message to send to the plugin
362 * @param origin the original sender of the message
363 * @param distnace distance to the original sender of the message
366 send_data_to_plugin (const struct GNUNET_MessageHeader *message,
367 const struct GNUNET_PeerIdentity *origin,
370 struct GNUNET_DV_ReceivedMessage *received_msg;
373 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
374 "Delivering message from peer `%s'\n",
375 GNUNET_i2s (origin));
376 size = sizeof (struct GNUNET_DV_ReceivedMessage) +
377 ntohs (message->size);
378 if (size >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
380 GNUNET_break (0); /* too big */
383 received_msg = GNUNET_malloc (size);
384 received_msg->header.size = htons (size);
385 received_msg->header.type = htons (GNUNET_MESSAGE_TYPE_DV_RECV);
386 received_msg->distance = htonl (distance);
387 received_msg->sender = *origin;
388 memcpy (&received_msg[1], message, ntohs (message->size));
389 GNUNET_SERVER_notification_context_broadcast (nc,
390 &received_msg->header,
392 GNUNET_free (received_msg);
397 * Forward a control message to the plugin.
399 * @param message the message to send to the plugin
400 * @param distant_neighbor the original sender of the message
401 * @param distnace distance to the original sender of the message
404 send_control_to_plugin (const struct GNUNET_MessageHeader *message)
406 GNUNET_SERVER_notification_context_broadcast (nc,
413 * Give an (N)ACK message to the plugin, we transmitted a message for it.
415 * @param target peer that received the message
416 * @param uid plugin-chosen UID for the message
417 * @param nack GNUNET_NO to send ACK, GNUNET_YES to send NACK
420 send_ack_to_plugin (const struct GNUNET_PeerIdentity *target,
424 struct GNUNET_DV_AckMessage ack_msg;
426 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
427 "Delivering ACK for message to peer `%s'\n",
428 GNUNET_i2s (target));
429 ack_msg.header.size = htons (sizeof (ack_msg));
430 ack_msg.header.type = htons ((GNUNET_YES == nack)
431 ? GNUNET_MESSAGE_TYPE_DV_SEND_NACK
432 : GNUNET_MESSAGE_TYPE_DV_SEND_ACK);
433 ack_msg.uid = htonl (uid);
434 ack_msg.target = *target;
435 send_control_to_plugin (&ack_msg.header);
440 * Send a DISTANCE_CHANGED message to the plugin.
442 * @param peer peer with a changed distance
443 * @param distance new distance to the peer
446 send_distance_change_to_plugin (const struct GNUNET_PeerIdentity *peer,
449 struct GNUNET_DV_DistanceUpdateMessage du_msg;
451 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
452 "Delivering DISTANCE_CHANGED for message about peer `%s'\n",
454 du_msg.header.size = htons (sizeof (du_msg));
455 du_msg.header.type = htons (GNUNET_MESSAGE_TYPE_DV_DISTANCE_CHANGED);
456 du_msg.distance = htonl (distance);
458 send_control_to_plugin (&du_msg.header);
463 * Give a CONNECT message to the plugin.
465 * @param target peer that connected
466 * @param distance distance to the target
469 send_connect_to_plugin (const struct GNUNET_PeerIdentity *target,
472 struct GNUNET_DV_ConnectMessage cm;
474 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
475 "Delivering CONNECT about peer `%s'\n",
476 GNUNET_i2s (target));
477 cm.header.size = htons (sizeof (cm));
478 cm.header.type = htons (GNUNET_MESSAGE_TYPE_DV_CONNECT);
479 cm.distance = htonl (distance);
481 send_control_to_plugin (&cm.header);
486 * Give a DISCONNECT message to the plugin.
488 * @param target peer that disconnected
491 send_disconnect_to_plugin (const struct GNUNET_PeerIdentity *target)
493 struct GNUNET_DV_DisconnectMessage dm;
495 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
496 "Delivering DISCONNECT about peer `%s'\n",
497 GNUNET_i2s (target));
498 dm.header.size = htons (sizeof (dm));
499 dm.header.type = htons (GNUNET_MESSAGE_TYPE_DV_DISCONNECT);
500 dm.reserved = htonl (0);
502 send_control_to_plugin (&dm.header);
507 * Function called to transfer a message to another peer
510 * @param cls closure with the direct neighbor
511 * @param size number of bytes available in buf
512 * @param buf where the callee should write the message
513 * @return number of bytes written to buf
516 core_transmit_notify (void *cls, size_t size, void *buf)
518 struct DirectNeighbor *dn = cls;
520 struct PendingMessage *pending;
527 /* peer disconnected */
531 pending = dn->pm_head;
533 while ( (NULL != (pending = dn->pm_head)) &&
534 (size >= off + (msize = ntohs (pending->msg->size))))
537 GNUNET_CONTAINER_DLL_remove (dn->pm_head,
540 memcpy (&cbuf[off], pending->msg, msize);
541 if (0 != pending->uid)
542 send_ack_to_plugin (&pending->ultimate_target,
545 GNUNET_free (pending);
548 if (NULL != dn->pm_head)
550 GNUNET_CORE_notify_transmit_ready (core_api,
551 GNUNET_YES /* cork */,
553 GNUNET_TIME_UNIT_FOREVER_REL,
556 &core_transmit_notify, dn);
562 * Forward the given payload to the given target.
564 * @param target where to send the message
565 * @param uid unique ID for the message
566 * @param ultimate_target ultimate recipient for the message
567 * @param distance expected (remaining) distance to the target
568 * @param sender original sender of the message
569 * @param payload payload of the message
572 forward_payload (struct DirectNeighbor *target,
575 const struct GNUNET_PeerIdentity *sender,
576 const struct GNUNET_PeerIdentity *ultimate_target,
577 const struct GNUNET_MessageHeader *payload)
579 struct PendingMessage *pm;
580 struct RouteMessage *rm;
583 if ( (target->pm_queue_size >= MAX_QUEUE_SIZE) &&
584 (0 != memcmp (sender,
586 sizeof (struct GNUNET_PeerIdentity))) )
588 GNUNET_break (0 == uid);
591 msize = sizeof (struct RouteMessage) + ntohs (payload->size);
592 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
597 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msize);
598 pm->ultimate_target = *ultimate_target;
600 pm->msg = (const struct GNUNET_MessageHeader *) &pm[1];
601 rm = (struct RouteMessage *) &pm[1];
602 rm->header.size = htons ((uint16_t) msize);
603 rm->header.type = htons (GNUNET_MESSAGE_TYPE_DV_ROUTE);
604 rm->distance = htonl (distance);
605 rm->target = target->peer;
606 rm->sender = *sender;
607 memcpy (&rm[1], payload, ntohs (payload->size));
608 GNUNET_CONTAINER_DLL_insert_tail (target->pm_head,
611 target->pm_queue_size++;
612 if (NULL == target->cth)
613 target->cth = GNUNET_CORE_notify_transmit_ready (core_api,
614 GNUNET_YES /* cork */,
616 GNUNET_TIME_UNIT_FOREVER_REL,
619 &core_transmit_notify, target);
624 * Find a free slot for storing a 'route' in the 'consensi'
625 * set at the given distance.
627 * @param distance distance to use for the set slot
630 get_consensus_slot (uint32_t distance)
632 struct ConsensusSet *cs;
635 cs = &consensi[distance];
637 while ( (i < cs->array_length) &&
638 (NULL != cs->targets[i]) ) i++;
639 if (i == cs->array_length)
640 GNUNET_array_grow (cs->targets,
642 cs->array_length * 2 + 2);
648 * Allocate a slot in the consensus set for a route.
650 * @param route route to initialize
651 * @param distance which consensus set to use
654 allocate_route (struct Route *route,
659 i = get_consensus_slot (distance);
660 route->set_offset = i;
661 consensi[distance].targets[i] = route;
662 route->target.distance = htonl (distance);
667 * Release a slot in the consensus set for a route.
669 * @param route route to release the slot from
672 release_route (struct Route *route)
674 consensi[ntohl (route->target.distance)].targets[route->set_offset] = NULL;
675 route->set_offset = UINT_MAX; /* indicate invalid slot */
680 * Move a route from one consensus set to another.
682 * @param route route to move
683 * @param new_distance new distance for the route (destination set)
686 move_route (struct Route *route,
687 uint32_t new_distance)
691 release_route (route);
692 i = get_consensus_slot (new_distance);
693 route->set_offset = i;
694 consensi[new_distance].targets[i] = route;
695 route->target.distance = htonl (new_distance);
700 * Start creating a new consensus from scratch.
702 * @param cls the 'struct DirectNeighbor' of the peer we're building
703 * a routing consensus with
704 * @param tc scheduler context
707 start_consensus (void *cls,
708 const struct GNUNET_SCHEDULER_TaskContext *tc);
712 * Method called whenever a peer connects.
715 * @param peer peer identity this notification is about
716 * @param atsi performance data
717 * @param atsi_count number of entries in atsi
720 handle_core_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
721 const struct GNUNET_ATS_Information *atsi,
722 unsigned int atsi_count)
724 struct DirectNeighbor *neighbor;
728 /* Check for connect to self message */
729 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
731 distance = get_atsi_distance (atsi, atsi_count);
732 neighbor = GNUNET_CONTAINER_multihashmap_get (direct_neighbors,
734 if (NULL != neighbor)
739 if (DIRECT_NEIGHBOR_COST != distance)
740 return; /* is a DV-neighbor */
741 GNUNET_STATISTICS_update (stats,
742 "# peers connected (1-hop)",
744 neighbor = GNUNET_malloc (sizeof (struct DirectNeighbor));
745 neighbor->peer = *peer;
746 GNUNET_assert (GNUNET_YES ==
747 GNUNET_CONTAINER_multihashmap_put (direct_neighbors,
750 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
751 route = GNUNET_CONTAINER_multihashmap_get (all_routes,
755 send_disconnect_to_plugin (peer);
756 release_route (route);
759 route->next_hop = neighbor;
760 neighbor->consensus_task = GNUNET_SCHEDULER_add_now (&start_consensus,
766 * Called for each 'target' in a neighbor table to free the associated memory.
769 * @param key key of the value
770 * @param value value to free
771 * @return GNUNET_OK to continue to iterate
774 free_targets (void *cls,
775 const struct GNUNET_HashCode *key,
784 * Multihashmap iterator for checking if a given route is
785 * (now) useful to this peer.
787 * @param cls the direct neighbor for the given route
788 * @param key key value stored under
789 * @param value a 'struct Target' that may or may not be useful; not that
790 * the distance in 'target' does not include the first hop yet
791 * @return GNUNET_YES to continue iteration, GNUNET_NO to stop
794 check_possible_route (void *cls, const struct GNUNET_HashCode * key, void *value)
796 struct DirectNeighbor *neighbor = cls;
797 struct Target *target = value;
800 route = GNUNET_CONTAINER_multihashmap_get (all_routes,
804 if (ntohl (route->target.distance) > ntohl (target->distance) + 1)
806 /* this 'target' is cheaper than the existing route; switch to alternative route! */
807 move_route (route, ntohl (target->distance) + 1);
808 route->next_hop = neighbor;
809 send_distance_change_to_plugin (&target->peer, ntohl (target->distance) + 1);
811 return GNUNET_YES; /* got a route to this target already */
813 route = GNUNET_malloc (sizeof (struct Route));
814 route->next_hop = neighbor;
815 route->target.distance = htonl (ntohl (target->distance) + 1);
816 route->target.peer = target->peer;
817 allocate_route (route, ntohl (route->target.distance));
818 GNUNET_assert (GNUNET_YES ==
819 GNUNET_CONTAINER_multihashmap_put (all_routes,
820 &route->target.peer.hashPubKey,
822 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
823 send_connect_to_plugin (&route->target.peer, ntohl (target->distance));
829 * Multihashmap iterator for finding routes that were previously
830 * "hidden" due to a better route (called after a disconnect event).
833 * @param key peer identity of the given direct neighbor
834 * @param value a 'struct DirectNeighbor' to check for additional routes
835 * @return GNUNET_YES to continue iteration
838 refresh_routes (void *cls, const struct GNUNET_HashCode * key, void *value)
840 struct DirectNeighbor *neighbor = value;
842 if (NULL != neighbor->neighbor_table)
843 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table,
844 &check_possible_route,
851 * Check if a target was removed from the set of the other peer; if so,
852 * if we also used it for our route, we need to remove it from our
853 * 'all_routes' set (and later check if an alternative path now exists).
855 * @param cls the 'struct DirectNeighbor'
856 * @param key peer identity for the target
857 * @param value a 'struct Target' previously reachable via the given neighbor
860 check_target_removed (void *cls,
861 const struct GNUNET_HashCode *key,
864 struct DirectNeighbor *neighbor = cls;
865 struct Target *new_target;
866 struct Route *current_route;
868 new_target = GNUNET_CONTAINER_multihashmap_get (neighbor->neighbor_table_consensus,
870 if (NULL == new_target)
872 /* target was revoked, check if it was used */
873 current_route = GNUNET_CONTAINER_multihashmap_get (all_routes,
875 if ( (NULL == current_route) ||
876 (current_route->next_hop != neighbor) )
878 /* didn't matter, wasn't used */
881 /* remove existing route */
882 GNUNET_assert (GNUNET_YES ==
883 GNUNET_CONTAINER_multihashmap_remove (all_routes, key, current_route));
884 send_disconnect_to_plugin (¤t_route->target.peer);
885 GNUNET_free (current_route);
886 neighbor->target_removed = GNUNET_YES;
894 * Check if a target was added to the set of the other peer; if it
895 * was added or impoves the existing route, do the needed updates.
897 * @param cls the 'struct DirectNeighbor'
898 * @param key peer identity for the target
899 * @param value a 'struct Target' now reachable via the given neighbor
902 check_target_added (void *cls,
903 const struct GNUNET_HashCode *key,
906 struct DirectNeighbor *neighbor = cls;
907 struct Target *target = value;
908 struct Route *current_route;
910 /* target was revoked, check if it was used */
911 current_route = GNUNET_CONTAINER_multihashmap_get (all_routes,
913 if (NULL != current_route)
916 if (current_route->next_hop == neighbor)
918 /* we had the same route before, no change */
919 if (ntohl (target->distance) + 1 != ntohl (current_route->target.distance))
921 current_route->target.distance = htonl (ntohl (target->distance) + 1);
922 send_distance_change_to_plugin (&target->peer, ntohl (target->distance) + 1);
926 if (ntohl (current_route->target.distance) >= ntohl (target->distance) + 1)
928 /* alternative, shorter route exists, ignore */
931 /* new route is better than the existing one, take over! */
932 /* NOTE: minor security issue: malicious peers may advertise
933 very short routes to take over longer paths; as we don't
934 check that the shorter routes actually work, a malicious
935 direct neighbor can use this to DoS our long routes */
936 current_route->next_hop = neighbor;
937 current_route->target.distance = htonl (ntohl (target->distance) + 1);
938 send_distance_change_to_plugin (&target->peer, ntohl (target->distance) + 1);
942 current_route = GNUNET_malloc (sizeof (struct Route));
943 current_route->next_hop = neighbor;
944 current_route->target.peer = target->peer;
945 current_route->target.distance = htonl (ntohl (target->distance) + 1);
946 GNUNET_assert (GNUNET_YES ==
947 GNUNET_CONTAINER_multihashmap_put (all_routes,
948 ¤t_route->target.peer.hashPubKey,
950 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
951 send_connect_to_plugin (¤t_route->target.peer,
952 ntohl (current_route->target.distance));
959 * The consensus has concluded, clean up and schedule the next one.
961 * @param cls the 'struct GNUNET_DirectNeighbor' with which we created the consensus
965 consensus_done_cb (void *cls,
966 const struct GNUNET_CONSENSUS_Group *group)
968 struct DirectNeighbor *neighbor = cls;
970 GNUNET_CONSENSUS_destroy (neighbor->consensus);
971 neighbor->consensus = NULL;
972 /* remove targets that disappeared */
973 neighbor->target_removed = GNUNET_NO;
974 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table,
975 &check_target_removed,
977 if (GNUNET_YES == neighbor->target_removed)
979 /* check if we got an alternative for the removed routes */
980 GNUNET_CONTAINER_multihashmap_iterate (direct_neighbors,
984 /* add targets that appeared (and check for improved routes) */
985 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table_consensus,
988 if (NULL != neighbor->neighbor_table)
990 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table,
993 GNUNET_CONTAINER_multihashmap_destroy (neighbor->neighbor_table);
994 neighbor->neighbor_table = NULL;
996 neighbor->neighbor_table = neighbor->neighbor_table_consensus;
997 neighbor->neighbor_table_consensus = NULL;
998 neighbor->consensus_task = GNUNET_SCHEDULER_add_delayed (GNUNET_DV_CONSENSUS_FREQUENCY,
1005 * We inserted the last element into the consensus, get ready to
1006 * insert the next element into the consensus or conclude if
1009 * @param cls the 'struct DirectNeighbor' of the peer we're building
1010 * a routing consensus with
1011 * @param success GNUNET_OK if the last element was added successfully,
1012 * GNUNET_SYSERR if we failed
1015 insert_next_element (void *cls,
1018 struct DirectNeighbor *neighbor = cls;
1019 struct GNUNET_CONSENSUS_Element element;
1021 while ( (DEFAULT_FISHEYE_DEPTH - 1 > neighbor->consensus_insertion_distance) &&
1022 (consensi[neighbor->consensus_insertion_distance].array_length == neighbor->consensus_insertion_offset) )
1024 neighbor->consensus_insertion_offset = 0;
1025 neighbor->consensus_insertion_distance++;
1026 /* skip over NULL entries */
1027 while ( (DEFAULT_FISHEYE_DEPTH - 1 > neighbor->consensus_insertion_distance) &&
1028 (consensi[neighbor->consensus_insertion_distance].array_length < neighbor->consensus_insertion_offset) &&
1029 (NULL == consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset]) )
1030 neighbor->consensus_insertion_offset++;
1032 if (DEFAULT_FISHEYE_DEPTH - 1 == neighbor->consensus_insertion_distance)
1034 /* we're done, conclude! */
1035 GNUNET_CONSENSUS_conclude (neighbor->consensus,
1036 GNUNET_DV_CONSENSUS_FREQUENCY,
1042 element.size = sizeof (struct Target);
1043 element.data = &consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset++]->target;
1045 /* skip over NULL entries */
1046 while ( (DEFAULT_FISHEYE_DEPTH - 1 > neighbor->consensus_insertion_distance) &&
1047 (consensi[neighbor->consensus_insertion_distance].array_length < neighbor->consensus_insertion_offset) &&
1048 (NULL == consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset]) )
1049 neighbor->consensus_insertion_offset++;
1050 GNUNET_CONSENSUS_insert (neighbor->consensus,
1052 &insert_next_element,
1058 * We have learned a new route from the other peer. Add it to the
1059 * route set we're building.
1061 * @param cls the 'struct DirectNeighbor' we're building the consensus with
1062 * @param element the new element we have learned
1063 * @return GNUNET_OK if the valid is well-formed and should be added to the consensus,
1064 * GNUNET_SYSERR if the element should be ignored and not be propagated
1067 learn_route_cb (void *cls,
1068 const struct GNUNET_CONSENSUS_Element *element)
1070 struct DirectNeighbor *neighbor = cls;
1071 struct Target *target;
1073 if (sizeof (struct Target) != element->size)
1075 GNUNET_break_op (0);
1076 return GNUNET_SYSERR;
1078 target = GNUNET_malloc (sizeof (struct Target));
1079 memcpy (target, element->data, sizeof (struct Target));
1081 GNUNET_CONTAINER_multihashmap_put (neighbor->neighbor_table_consensus,
1082 &target->peer.hashPubKey,
1084 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
1086 GNUNET_break_op (0);
1087 GNUNET_free (target);
1088 return GNUNET_SYSERR;
1095 * Start creating a new consensus from scratch.
1097 * @param cls the 'struct DirectNeighbor' of the peer we're building
1098 * a routing consensus with
1099 * @param tc scheduler context
1102 start_consensus (void *cls,
1103 const struct GNUNET_SCHEDULER_TaskContext *tc)
1105 struct DirectNeighbor *neighbor = cls;
1106 struct GNUNET_HashCode session_id;
1107 struct GNUNET_HashCode real_session_id;
1109 neighbor->consensus_task = GNUNET_SCHEDULER_NO_TASK;
1110 neighbor->consensus_insertion_offset = 0;
1111 neighbor->consensus_insertion_distance = 0;
1112 GNUNET_assert (NULL == neighbor->neighbor_table_consensus);
1113 GNUNET_assert (NULL == neighbor->consensus);
1114 neighbor->neighbor_table_consensus = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_YES);
1115 /* construct session ID seed as XOR of both peer's identities */
1116 GNUNET_CRYPTO_hash_xor (&my_identity.hashPubKey,
1117 &neighbor->peer.hashPubKey,
1119 /* make sure session ID is unique across applications by salting it with 'DV' */
1120 GNUNET_CRYPTO_hkdf (&real_session_id, sizeof (real_session_id),
1121 GCRY_MD_SHA512, GCRY_MD_SHA256,
1123 &session_id, sizeof (session_id),
1125 neighbor->consensus = GNUNET_CONSENSUS_create (cfg,
1131 if (NULL == neighbor->consensus)
1133 neighbor->consensus_task = GNUNET_SCHEDULER_add_delayed (GNUNET_DV_CONSENSUS_FREQUENCY,
1138 insert_next_element (neighbor, GNUNET_OK);
1143 * Core handler for DV data messages. Whatever this message
1144 * contains all we really have to do is rip it out of its
1145 * DV layering and give it to our pal the DV plugin to report
1148 * @param cls closure
1149 * @param peer peer which sent the message (immediate sender)
1150 * @param message the message
1151 * @param atsi transport ATS information (latency, distance, etc.)
1152 * @param atsi_count number of entries in atsi
1153 * @return GNUNET_OK on success, GNUNET_SYSERR if the other peer violated the protocol
1156 handle_dv_route_message (void *cls, const struct GNUNET_PeerIdentity *peer,
1157 const struct GNUNET_MessageHeader *message,
1158 const struct GNUNET_ATS_Information *atsi,
1159 unsigned int atsi_count)
1161 const struct RouteMessage *rm;
1162 const struct GNUNET_MessageHeader *payload;
1163 struct Route *route;
1165 if (ntohs (message->size) < sizeof (struct RouteMessage) + sizeof (struct GNUNET_MessageHeader))
1167 GNUNET_break_op (0);
1168 return GNUNET_SYSERR;
1170 rm = (const struct RouteMessage *) message;
1171 payload = (const struct GNUNET_MessageHeader *) &rm[1];
1172 if (ntohs (message->size) != sizeof (struct RouteMessage) + ntohs (payload->size))
1174 GNUNET_break_op (0);
1175 return GNUNET_SYSERR;
1177 if (0 == memcmp (&rm->target,
1179 sizeof (struct GNUNET_PeerIdentity)))
1181 /* message is for me, check reverse route! */
1182 route = GNUNET_CONTAINER_multihashmap_get (all_routes,
1183 &rm->sender.hashPubKey);
1186 /* don't have reverse route, drop */
1187 GNUNET_STATISTICS_update (stats,
1188 "# message discarded (no reverse route)",
1192 send_data_to_plugin (payload,
1194 ntohl (route->target.distance));
1197 route = GNUNET_CONTAINER_multihashmap_get (all_routes,
1198 &rm->target.hashPubKey);
1201 GNUNET_STATISTICS_update (stats,
1202 "# messages discarded (no route)",
1206 if (ntohl (route->target.distance) > ntohl (rm->distance) + 1)
1208 GNUNET_STATISTICS_update (stats,
1209 "# messages discarded (target too far)",
1213 forward_payload (route->next_hop,
1214 ntohl (route->target.distance),
1224 * Service server's handler for message send requests (which come
1225 * bubbling up to us through the DV plugin).
1227 * @param cls closure
1228 * @param client identification of the client
1229 * @param message the actual message
1232 handle_dv_send_message (void *cls, struct GNUNET_SERVER_Client *client,
1233 const struct GNUNET_MessageHeader *message)
1235 struct Route *route;
1236 const struct GNUNET_DV_SendMessage *msg;
1237 const struct GNUNET_MessageHeader *payload;
1239 if (ntohs (message->size) < sizeof (struct GNUNET_DV_SendMessage) + sizeof (struct GNUNET_MessageHeader))
1242 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1245 msg = (const struct GNUNET_DV_SendMessage *) message;
1246 GNUNET_break (0 != ntohl (msg->uid));
1247 payload = (const struct GNUNET_MessageHeader *) &msg[1];
1248 if (ntohs (message->size) != sizeof (struct GNUNET_DV_SendMessage) + ntohs (payload->size))
1251 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1254 route = GNUNET_CONTAINER_multihashmap_get (all_routes,
1255 &msg->target.hashPubKey);
1258 /* got disconnected */
1259 GNUNET_STATISTICS_update (stats,
1260 "# local messages discarded (no route)",
1262 send_ack_to_plugin (&msg->target, ntohl (msg->uid), GNUNET_YES);
1263 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1266 forward_payload (route->next_hop,
1267 ntohl (route->target.distance),
1272 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1277 * Multihashmap iterator for freeing routes that go via a particular
1278 * neighbor that disconnected and is thus no longer available.
1280 * @param cls the direct neighbor that is now unavailable
1281 * @param key key value stored under
1282 * @param value a 'struct Route' that may or may not go via neighbor
1284 * @return GNUNET_YES to continue iteration, GNUNET_NO to stop
1287 cull_routes (void *cls, const struct GNUNET_HashCode * key, void *value)
1289 struct DirectNeighbor *neighbor = cls;
1290 struct Route *route = value;
1292 if (route->next_hop != neighbor)
1293 return GNUNET_YES; /* not affected */
1294 GNUNET_assert (GNUNET_YES ==
1295 GNUNET_CONTAINER_multihashmap_remove (all_routes, key, value));
1296 release_route (route);
1297 send_disconnect_to_plugin (&route->target.peer);
1298 GNUNET_free (route);
1304 * Cleanup all of the data structures associated with a given neighbor.
1306 * @param neighbor neighbor to clean up
1309 cleanup_neighbor (struct DirectNeighbor *neighbor)
1311 struct PendingMessage *pending;
1313 while (NULL != (pending = neighbor->pm_head))
1315 neighbor->pm_queue_size--;
1316 GNUNET_CONTAINER_DLL_remove (neighbor->pm_head,
1319 GNUNET_free (pending);
1321 GNUNET_CONTAINER_multihashmap_iterate (all_routes,
1324 if (NULL != neighbor->cth)
1326 GNUNET_CORE_notify_transmit_ready_cancel (neighbor->cth);
1327 neighbor->cth = NULL;
1329 if (NULL != neighbor->neighbor_table_consensus)
1331 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table_consensus,
1334 GNUNET_CONTAINER_multihashmap_destroy (neighbor->neighbor_table_consensus);
1335 neighbor->neighbor_table_consensus = NULL;
1337 if (NULL != neighbor->neighbor_table)
1339 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table,
1342 GNUNET_CONTAINER_multihashmap_destroy (neighbor->neighbor_table);
1343 neighbor->neighbor_table = NULL;
1345 if (GNUNET_SCHEDULER_NO_TASK != neighbor->consensus_task)
1347 GNUNET_SCHEDULER_cancel (neighbor->consensus_task);
1348 neighbor->consensus_task = GNUNET_SCHEDULER_NO_TASK;
1350 if (NULL != neighbor->consensus)
1352 GNUNET_CONSENSUS_destroy (neighbor->consensus);
1353 neighbor->consensus = NULL;
1355 GNUNET_assert (GNUNET_YES ==
1356 GNUNET_CONTAINER_multihashmap_remove (direct_neighbors,
1357 &neighbor->peer.hashPubKey,
1359 GNUNET_free (neighbor);
1364 * Method called whenever a given peer disconnects.
1366 * @param cls closure
1367 * @param peer peer identity this notification is about
1370 handle_core_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
1372 struct DirectNeighbor *neighbor;
1374 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1375 "Received core peer disconnect message for peer `%s'!\n",
1377 /* Check for disconnect from self message */
1378 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
1381 GNUNET_CONTAINER_multihashmap_get (direct_neighbors, &peer->hashPubKey);
1382 if (NULL == neighbor)
1384 /* must have been a DV-neighbor, ignore */
1387 GNUNET_STATISTICS_update (stats,
1388 "# peers connected (1-hop)",
1390 cleanup_neighbor (neighbor);
1391 GNUNET_CONTAINER_multihashmap_iterate (direct_neighbors,
1398 * Multihashmap iterator for freeing routes. Should never be called.
1401 * @param key key value stored under
1402 * @param value the route to be freed
1404 * @return GNUNET_YES to continue iteration, GNUNET_NO to stop
1407 free_route (void *cls, const struct GNUNET_HashCode * key, void *value)
1409 struct Route *route = value;
1412 GNUNET_assert (GNUNET_YES ==
1413 GNUNET_CONTAINER_multihashmap_remove (all_routes, key, value));
1414 release_route (route);
1415 send_disconnect_to_plugin (&route->target.peer);
1416 GNUNET_free (route);
1422 * Multihashmap iterator for freeing direct neighbors. Should never be called.
1425 * @param key key value stored under
1426 * @param value the direct neighbor to be freed
1428 * @return GNUNET_YES to continue iteration, GNUNET_NO to stop
1431 free_direct_neighbors (void *cls, const struct GNUNET_HashCode * key, void *value)
1433 struct DirectNeighbor *neighbor = value;
1436 cleanup_neighbor (neighbor);
1442 * Task run during shutdown.
1448 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1452 GNUNET_CONTAINER_multihashmap_iterate (direct_neighbors,
1453 &free_direct_neighbors, NULL);
1454 GNUNET_CONTAINER_multihashmap_destroy (direct_neighbors);
1455 GNUNET_CONTAINER_multihashmap_iterate (all_routes,
1457 GNUNET_CONTAINER_multihashmap_destroy (all_routes);
1458 GNUNET_CORE_disconnect (core_api);
1460 GNUNET_STATISTICS_destroy (stats, GNUNET_NO);
1462 GNUNET_SERVER_notification_context_destroy (nc);
1464 for (i=0;i<DEFAULT_FISHEYE_DEPTH - 1;i++)
1465 GNUNET_array_grow (consensi[i].targets,
1466 consensi[i].array_length,
1472 * Notify newly connected client about an existing route.
1474 * @param cls the 'struct GNUNET_SERVER_Client'
1475 * @param key peer identity
1476 * @param value the XXX.
1477 * @return GNUNET_OK (continue to iterate)
1480 add_route (void *cls,
1481 const struct GNUNET_HashCode *key,
1484 struct GNUNET_SERVER_Client *client = cls;
1485 struct Route *route = value;
1486 struct GNUNET_DV_ConnectMessage cm;
1488 cm.header.size = htons (sizeof (cm));
1489 cm.header.type = htons (GNUNET_MESSAGE_TYPE_DV_CONNECT);
1490 cm.distance = htonl (route->target.distance);
1491 cm.peer = route->target.peer;
1493 GNUNET_SERVER_notification_context_unicast (nc,
1502 * Handle START-message. This is the first message sent to us
1503 * by the client (can only be one!).
1505 * @param cls closure (always NULL)
1506 * @param client identification of the client
1507 * @param message the actual message
1510 handle_start (void *cls, struct GNUNET_SERVER_Client *client,
1511 const struct GNUNET_MessageHeader *message)
1513 GNUNET_SERVER_notification_context_add (nc, client);
1514 GNUNET_CONTAINER_multihashmap_iterate (all_routes,
1521 * Called on core init.
1524 * @param server legacy
1525 * @param identity this peer's identity
1528 core_init (void *cls, struct GNUNET_CORE_Handle *server,
1529 const struct GNUNET_PeerIdentity *identity)
1531 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1533 GNUNET_i2s (identity));
1534 my_identity = *identity;
1539 * Process dv requests.
1541 * @param cls closure
1542 * @param server the initialized server
1543 * @param c configuration to use
1546 run (void *cls, struct GNUNET_SERVER_Handle *server,
1547 const struct GNUNET_CONFIGURATION_Handle *c)
1549 static struct GNUNET_CORE_MessageHandler core_handlers[] = {
1550 {&handle_dv_route_message, GNUNET_MESSAGE_TYPE_DV_ROUTE, 0},
1553 static struct GNUNET_SERVER_MessageHandler plugin_handlers[] = {
1554 {&handle_start, NULL,
1555 GNUNET_MESSAGE_TYPE_DV_START,
1556 sizeof (struct GNUNET_MessageHeader) },
1557 { &handle_dv_send_message, NULL,
1558 GNUNET_MESSAGE_TYPE_DV_SEND,
1564 direct_neighbors = GNUNET_CONTAINER_multihashmap_create (128, GNUNET_NO);
1565 all_routes = GNUNET_CONTAINER_multihashmap_create (65536, GNUNET_NO);
1566 core_api = GNUNET_CORE_connect (cfg, NULL,
1568 &handle_core_connect,
1569 &handle_core_disconnect,
1574 if (NULL == core_api)
1576 nc = GNUNET_SERVER_notification_context_create (server,
1577 MAX_QUEUE_SIZE_PLUGIN);
1578 stats = GNUNET_STATISTICS_create ("dv", cfg);
1579 GNUNET_SERVER_add_handlers (server, plugin_handlers);
1580 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
1581 &shutdown_task, NULL);
1586 * The main function for the dv service.
1588 * @param argc number of arguments from the command line
1589 * @param argv command line arguments
1590 * @return 0 ok, 1 on error
1593 main (int argc, char *const *argv)
1595 return (GNUNET_OK ==
1596 GNUNET_SERVICE_run (argc, argv, "dv", GNUNET_SERVICE_OPTION_NONE,
1597 &run, NULL)) ? 0 : 1;
1600 /* end of gnunet-service-dv.c */