2 This file is part of GNUnet.
3 (C) 2013 Christian Grothoff (and other contributing authors)
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.
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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.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
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 #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_consensus_service.h"
38 #include "gnunet_ats_service.h"
44 * How often do we establish the consensu?
46 #define GNUNET_DV_CONSENSUS_FREQUENCY GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 5)
49 * Maximum number of messages we queue per peer.
51 #define MAX_QUEUE_SIZE 16
54 * Maximum number of messages we queue towards the clients/plugin.
56 #define MAX_QUEUE_SIZE_PLUGIN 1024
59 * The default fisheye depth, from how many hops away will
62 #define DEFAULT_FISHEYE_DEPTH 3
65 * How many hops is a direct neighbor away?
67 #define DIRECT_NEIGHBOR_COST 1
70 GNUNET_NETWORK_STRUCT_BEGIN
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.
81 * Identity of the peer we can reach.
83 struct GNUNET_PeerIdentity peer;
86 * How many hops (1-3) is this peer away? in network byte order
88 uint32_t distance GNUNET_PACKED;
94 * Message exchanged between DV services (via core), requesting a
95 * message to be routed.
100 * Type: GNUNET_MESSAGE_TYPE_DV_ROUTE
102 struct GNUNET_MessageHeader header;
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.
110 uint32_t distance GNUNET_PACKED;
113 * The (actual) target of the message (this peer, if distance is zero).
115 struct GNUNET_PeerIdentity target;
118 * The (actual) sender of the message.
120 struct GNUNET_PeerIdentity sender;
124 GNUNET_NETWORK_STRUCT_END
128 * Linked list of messages to send to clients.
130 struct PendingMessage
133 * Pointer to next item in the list
135 struct PendingMessage *next;
138 * Pointer to previous item in the list
140 struct PendingMessage *prev;
143 * Actual message to be sent, allocated after this struct.
145 const struct GNUNET_MessageHeader *msg;
148 * Ultimate target for the message.
150 struct GNUNET_PeerIdentity ultimate_target;
153 * Unique ID of the message.
161 * Information about a direct neighbor (core-level, excluding
162 * DV-links, only DV-enabled peers).
164 struct DirectNeighbor
168 * Identity of the peer.
170 struct GNUNET_PeerIdentity peer;
173 * Head of linked list of messages to send to this peer.
175 struct PendingMessage *pm_head;
178 * Tail of linked list of messages to send to this peer.
180 struct PendingMessage *pm_tail;
183 * Transmit handle to core service.
185 struct GNUNET_CORE_TransmitHandle *cth;
188 * Routing table of the neighbor, NULL if not yet established.
189 * Keys are peer identities, values are 'struct Target' entries.
190 * Note that the distances in the targets are from the point-of-view
191 * of the peer, not from us!
193 struct GNUNET_CONTAINER_MultiHashMap *neighbor_table;
196 * Updated routing table of the neighbor, under construction,
197 * NULL if we are not currently building it.
198 * Keys are peer identities, values are 'struct Target' entries.
199 * Note that the distances in the targets are from the point-of-view
200 * of the peer, not from us!
202 struct GNUNET_CONTAINER_MultiHashMap *neighbor_table_consensus;
205 * Active consensus, if we are currently synchronizing the
208 struct GNUNET_CONSENSUS_Handle *consensus;
211 * ID of the task we use to (periodically) update our consensus
214 GNUNET_SCHEDULER_TaskIdentifier consensus_task;
217 * At what offset are we, with respect to inserting our own routes
218 * into the consensus?
220 unsigned int consensus_insertion_offset;
223 * At what distance are we, with respect to inserting our own routes
224 * into the consensus?
226 unsigned int consensus_insertion_distance;
229 * Number of messages currently in the 'pm_XXXX'-DLL.
231 unsigned int pm_queue_size;
234 * Flag set within 'check_target_removed' to trigger full global route refresh.
239 * Our distance to this peer, 0 for unknown.
244 * Is this neighbor connected at the core level?
252 * A route includes information about the next hop,
253 * the target, and the ultimate distance to the
260 * Which peer do we need to forward the message to?
262 struct DirectNeighbor *next_hop;
265 * What would be the target, and how far is it away?
267 struct Target target;
270 * Offset of this target in the respective consensus set.
272 unsigned int set_offset;
278 * Set of targets we bring to a consensus; all targets in a set have a
279 * distance equal to the sets distance (which is implied by the array
286 * Array of targets in the set, may include NULL entries if a
287 * neighbor has disconnected; the targets are allocated with the
288 * respective container (all_routes), not here.
290 struct Route **targets;
293 * Size of the 'targets' array.
295 unsigned int array_length;
301 * Hashmap of all of our neighbors; processing these usually requires
302 * first checking to see if the peer is core-connected and if the
303 * distance is 1, in which case they are direct neighbors.
305 static struct GNUNET_CONTAINER_MultiHashMap *direct_neighbors;
308 * Hashmap with all routes that we currently support; contains
309 * routing information for all peers from distance 2
310 * up to distance DEFAULT_FISHEYE_DEPTH.
312 static struct GNUNET_CONTAINER_MultiHashMap *all_routes;
315 * Array of consensus sets we expose to the outside world. Sets
316 * are structured by the distance to the target.
318 static struct ConsensusSet consensi[DEFAULT_FISHEYE_DEPTH - 1];
321 * Handle to the core service api.
323 static struct GNUNET_CORE_Handle *core_api;
326 * The identity of our peer.
328 static struct GNUNET_PeerIdentity my_identity;
331 * The configuration for this service.
333 static const struct GNUNET_CONFIGURATION_Handle *cfg;
336 * The client, the DV plugin connected to us (or an event monitor).
337 * Hopefully this client will never change, although if the plugin
338 * dies and returns for some reason it may happen.
340 static struct GNUNET_SERVER_NotificationContext *nc;
343 * Handle for the statistics service.
345 static struct GNUNET_STATISTICS_Handle *stats;
348 * Handle to ATS service.
350 static struct GNUNET_ATS_PerformanceHandle *ats;
354 * Start creating a new consensus from scratch.
356 * @param cls the 'struct DirectNeighbor' of the peer we're building
357 * a routing consensus with
358 * @param tc scheduler context
361 start_consensus (void *cls,
362 const struct GNUNET_SCHEDULER_TaskContext *tc);
366 * Forward a message from another peer to the plugin.
368 * @param message the message to send to the plugin
369 * @param origin the original sender of the message
370 * @param distance distance to the original sender of the message
373 send_data_to_plugin (const struct GNUNET_MessageHeader *message,
374 const struct GNUNET_PeerIdentity *origin,
377 struct GNUNET_DV_ReceivedMessage *received_msg;
380 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
381 "Delivering message from peer `%s'\n",
382 GNUNET_i2s (origin));
383 size = sizeof (struct GNUNET_DV_ReceivedMessage) +
384 ntohs (message->size);
385 if (size >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
387 GNUNET_break (0); /* too big */
390 received_msg = GNUNET_malloc (size);
391 received_msg->header.size = htons (size);
392 received_msg->header.type = htons (GNUNET_MESSAGE_TYPE_DV_RECV);
393 received_msg->distance = htonl (distance);
394 received_msg->sender = *origin;
395 memcpy (&received_msg[1], message, ntohs (message->size));
396 GNUNET_SERVER_notification_context_broadcast (nc,
397 &received_msg->header,
399 GNUNET_free (received_msg);
404 * Forward a control message to the plugin.
406 * @param message the message to send to the plugin
409 send_control_to_plugin (const struct GNUNET_MessageHeader *message)
411 GNUNET_SERVER_notification_context_broadcast (nc,
418 * Give an (N)ACK message to the plugin, we transmitted a message for it.
420 * @param target peer that received the message
421 * @param uid plugin-chosen UID for the message
422 * @param nack GNUNET_NO to send ACK, GNUNET_YES to send NACK
425 send_ack_to_plugin (const struct GNUNET_PeerIdentity *target,
429 struct GNUNET_DV_AckMessage ack_msg;
431 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
432 "Delivering ACK for message to peer `%s'\n",
433 GNUNET_i2s (target));
434 ack_msg.header.size = htons (sizeof (ack_msg));
435 ack_msg.header.type = htons ((GNUNET_YES == nack)
436 ? GNUNET_MESSAGE_TYPE_DV_SEND_NACK
437 : GNUNET_MESSAGE_TYPE_DV_SEND_ACK);
438 ack_msg.uid = htonl (uid);
439 ack_msg.target = *target;
440 send_control_to_plugin (&ack_msg.header);
445 * Send a DISTANCE_CHANGED message to the plugin.
447 * @param peer peer with a changed distance
448 * @param distance new distance to the peer
451 send_distance_change_to_plugin (const struct GNUNET_PeerIdentity *peer,
454 struct GNUNET_DV_DistanceUpdateMessage du_msg;
456 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
457 "Delivering DISTANCE_CHANGED for message about peer `%s'\n",
459 du_msg.header.size = htons (sizeof (du_msg));
460 du_msg.header.type = htons (GNUNET_MESSAGE_TYPE_DV_DISTANCE_CHANGED);
461 du_msg.distance = htonl (distance);
463 send_control_to_plugin (&du_msg.header);
468 * Give a CONNECT message to the plugin.
470 * @param target peer that connected
471 * @param distance distance to the target
474 send_connect_to_plugin (const struct GNUNET_PeerIdentity *target,
477 struct GNUNET_DV_ConnectMessage cm;
479 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
480 "Delivering CONNECT about peer `%s'\n",
481 GNUNET_i2s (target));
482 cm.header.size = htons (sizeof (cm));
483 cm.header.type = htons (GNUNET_MESSAGE_TYPE_DV_CONNECT);
484 cm.distance = htonl (distance);
486 send_control_to_plugin (&cm.header);
491 * Give a DISCONNECT message to the plugin.
493 * @param target peer that disconnected
496 send_disconnect_to_plugin (const struct GNUNET_PeerIdentity *target)
498 struct GNUNET_DV_DisconnectMessage dm;
500 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
501 "Delivering DISCONNECT about peer `%s'\n",
502 GNUNET_i2s (target));
503 dm.header.size = htons (sizeof (dm));
504 dm.header.type = htons (GNUNET_MESSAGE_TYPE_DV_DISCONNECT);
505 dm.reserved = htonl (0);
507 send_control_to_plugin (&dm.header);
512 * Function called to transfer a message to another peer
515 * @param cls closure with the direct neighbor
516 * @param size number of bytes available in buf
517 * @param buf where the callee should write the message
518 * @return number of bytes written to buf
521 core_transmit_notify (void *cls, size_t size, void *buf)
523 struct DirectNeighbor *dn = cls;
525 struct PendingMessage *pending;
532 /* peer disconnected */
536 pending = dn->pm_head;
538 while ( (NULL != (pending = dn->pm_head)) &&
539 (size >= off + (msize = ntohs (pending->msg->size))))
542 GNUNET_CONTAINER_DLL_remove (dn->pm_head,
545 memcpy (&cbuf[off], pending->msg, msize);
546 if (0 != pending->uid)
547 send_ack_to_plugin (&pending->ultimate_target,
550 GNUNET_free (pending);
553 if (NULL != dn->pm_head)
555 GNUNET_CORE_notify_transmit_ready (core_api,
556 GNUNET_YES /* cork */,
558 GNUNET_TIME_UNIT_FOREVER_REL,
561 &core_transmit_notify, dn);
567 * Forward the given payload to the given target.
569 * @param target where to send the message
570 * @param uid unique ID for the message
571 * @param ultimate_target ultimate recipient for the message
572 * @param distance expected (remaining) distance to the target
573 * @param sender original sender of the message
574 * @param payload payload of the message
577 forward_payload (struct DirectNeighbor *target,
580 const struct GNUNET_PeerIdentity *sender,
581 const struct GNUNET_PeerIdentity *ultimate_target,
582 const struct GNUNET_MessageHeader *payload)
584 struct PendingMessage *pm;
585 struct RouteMessage *rm;
588 if ( (target->pm_queue_size >= MAX_QUEUE_SIZE) &&
589 (0 != memcmp (sender,
591 sizeof (struct GNUNET_PeerIdentity))) )
593 GNUNET_break (0 == uid);
596 msize = sizeof (struct RouteMessage) + ntohs (payload->size);
597 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
602 pm = GNUNET_malloc (sizeof (struct PendingMessage) + msize);
603 pm->ultimate_target = *ultimate_target;
605 pm->msg = (const struct GNUNET_MessageHeader *) &pm[1];
606 rm = (struct RouteMessage *) &pm[1];
607 rm->header.size = htons ((uint16_t) msize);
608 rm->header.type = htons (GNUNET_MESSAGE_TYPE_DV_ROUTE);
609 rm->distance = htonl (distance);
610 rm->target = target->peer;
611 rm->sender = *sender;
612 memcpy (&rm[1], payload, ntohs (payload->size));
613 GNUNET_CONTAINER_DLL_insert_tail (target->pm_head,
616 target->pm_queue_size++;
617 if (NULL == target->cth)
618 target->cth = GNUNET_CORE_notify_transmit_ready (core_api,
619 GNUNET_YES /* cork */,
621 GNUNET_TIME_UNIT_FOREVER_REL,
624 &core_transmit_notify, target);
629 * Find a free slot for storing a 'route' in the 'consensi'
630 * set at the given distance.
632 * @param distance distance to use for the set slot
635 get_consensus_slot (uint32_t distance)
637 struct ConsensusSet *cs;
640 cs = &consensi[distance];
642 while ( (i < cs->array_length) &&
643 (NULL != cs->targets[i]) ) i++;
644 if (i == cs->array_length)
645 GNUNET_array_grow (cs->targets,
647 cs->array_length * 2 + 2);
653 * Allocate a slot in the consensus set for a route.
655 * @param route route to initialize
656 * @param distance which consensus set to use
659 allocate_route (struct Route *route,
664 i = get_consensus_slot (distance);
665 route->set_offset = i;
666 consensi[distance].targets[i] = route;
667 route->target.distance = htonl (distance);
672 * Release a slot in the consensus set for a route.
674 * @param route route to release the slot from
677 release_route (struct Route *route)
679 consensi[ntohl (route->target.distance)].targets[route->set_offset] = NULL;
680 route->set_offset = UINT_MAX; /* indicate invalid slot */
685 * Move a route from one consensus set to another.
687 * @param route route to move
688 * @param new_distance new distance for the route (destination set)
691 move_route (struct Route *route,
692 uint32_t new_distance)
696 release_route (route);
697 i = get_consensus_slot (new_distance);
698 route->set_offset = i;
699 consensi[new_distance].targets[i] = route;
700 route->target.distance = htonl (new_distance);
705 * A peer is now connected to us at distance 1. Initiate DV exchange.
707 * @param neighbor entry for the neighbor at distance 1
710 handle_direct_connect (struct DirectNeighbor *neighbor)
714 GNUNET_STATISTICS_update (stats,
715 "# peers connected (1-hop)",
717 route = GNUNET_CONTAINER_multihashmap_get (all_routes,
718 &neighbor->peer.hashPubKey);
721 send_disconnect_to_plugin (&neighbor->peer);
722 release_route (route);
725 neighbor->consensus_task = GNUNET_SCHEDULER_add_now (&start_consensus,
731 * Method called whenever a peer connects.
734 * @param peer peer identity this notification is about
737 handle_core_connect (void *cls, const struct GNUNET_PeerIdentity *peer)
739 struct DirectNeighbor *neighbor;
741 /* Check for connect to self message */
742 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
744 /* check if entry exists */
745 neighbor = GNUNET_CONTAINER_multihashmap_get (direct_neighbors,
747 if (NULL != neighbor)
749 GNUNET_break (GNUNET_YES != neighbor->connected);
750 neighbor->connected = GNUNET_YES;
751 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
752 "Core connected to %s (distance %u)\n",
754 (unsigned int) neighbor->distance);
755 if (DIRECT_NEIGHBOR_COST != neighbor->distance)
757 handle_direct_connect (neighbor);
760 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
761 "Core connected to %s (distance unknown)\n",
763 neighbor = GNUNET_malloc (sizeof (struct DirectNeighbor));
764 neighbor->peer = *peer;
765 GNUNET_assert (GNUNET_YES ==
766 GNUNET_CONTAINER_multihashmap_put (direct_neighbors,
769 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
770 neighbor->connected = GNUNET_YES;
771 neighbor->distance = 0; /* unknown */
776 * Called for each 'target' in a neighbor table to free the associated memory.
779 * @param key key of the value
780 * @param value value to free
781 * @return GNUNET_OK to continue to iterate
784 free_targets (void *cls,
785 const struct GNUNET_HashCode *key,
794 * Multihashmap iterator for checking if a given route is
795 * (now) useful to this peer.
797 * @param cls the direct neighbor for the given route
798 * @param key key value stored under
799 * @param value a 'struct Target' that may or may not be useful; not that
800 * the distance in 'target' does not include the first hop yet
801 * @return GNUNET_YES to continue iteration, GNUNET_NO to stop
804 check_possible_route (void *cls, const struct GNUNET_HashCode * key, void *value)
806 struct DirectNeighbor *neighbor = cls;
807 struct Target *target = value;
810 route = GNUNET_CONTAINER_multihashmap_get (all_routes,
814 if (ntohl (route->target.distance) > ntohl (target->distance) + 1)
816 /* this 'target' is cheaper than the existing route; switch to alternative route! */
817 move_route (route, ntohl (target->distance) + 1);
818 route->next_hop = neighbor;
819 send_distance_change_to_plugin (&target->peer, ntohl (target->distance) + 1);
821 return GNUNET_YES; /* got a route to this target already */
823 route = GNUNET_malloc (sizeof (struct Route));
824 route->next_hop = neighbor;
825 route->target.distance = htonl (ntohl (target->distance) + 1);
826 route->target.peer = target->peer;
827 allocate_route (route, ntohl (route->target.distance));
828 GNUNET_assert (GNUNET_YES ==
829 GNUNET_CONTAINER_multihashmap_put (all_routes,
830 &route->target.peer.hashPubKey,
832 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
833 send_connect_to_plugin (&route->target.peer, ntohl (target->distance));
839 * Multihashmap iterator for finding routes that were previously
840 * "hidden" due to a better route (called after a disconnect event).
843 * @param key peer identity of the given direct neighbor
844 * @param value a 'struct DirectNeighbor' to check for additional routes
845 * @return GNUNET_YES to continue iteration
848 refresh_routes (void *cls, const struct GNUNET_HashCode * key, void *value)
850 struct DirectNeighbor *neighbor = value;
852 if ( (GNUNET_YES != neighbor->connected) ||
853 (DIRECT_NEIGHBOR_COST != neighbor->distance) )
855 if (NULL != neighbor->neighbor_table)
856 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table,
857 &check_possible_route,
864 * Get distance information from 'atsi'.
866 * @param atsi performance data
867 * @param atsi_count number of entries in atsi
868 * @return connected transport distance
871 get_atsi_distance (const struct GNUNET_ATS_Information *atsi,
876 for (i = 0; i < atsi_count; i++)
877 if (ntohl (atsi[i].type) == GNUNET_ATS_QUALITY_NET_DISTANCE)
878 return ntohl (atsi->value);
879 /* If we do not have explicit distance data, assume direct neighbor. */
880 return DIRECT_NEIGHBOR_COST;
885 * Multihashmap iterator for freeing routes that go via a particular
886 * neighbor that disconnected and is thus no longer available.
888 * @param cls the direct neighbor that is now unavailable
889 * @param key key value stored under
890 * @param value a 'struct Route' that may or may not go via neighbor
892 * @return GNUNET_YES to continue iteration, GNUNET_NO to stop
895 cull_routes (void *cls, const struct GNUNET_HashCode * key, void *value)
897 struct DirectNeighbor *neighbor = cls;
898 struct Route *route = value;
900 if (route->next_hop != neighbor)
901 return GNUNET_YES; /* not affected */
902 GNUNET_assert (GNUNET_YES ==
903 GNUNET_CONTAINER_multihashmap_remove (all_routes, key, value));
904 release_route (route);
905 send_disconnect_to_plugin (&route->target.peer);
912 * Handle the case that a direct connection to a peer is
913 * disrupted. Remove all routes via that peer and
914 * stop the consensus with it.
916 * @param neighbor peer that was disconnected (or at least is no
917 * longer at distance 1)
920 handle_direct_disconnect (struct DirectNeighbor *neighbor)
922 GNUNET_CONTAINER_multihashmap_iterate (all_routes,
925 if (NULL != neighbor->cth)
927 GNUNET_CORE_notify_transmit_ready_cancel (neighbor->cth);
928 neighbor->cth = NULL;
930 if (NULL != neighbor->neighbor_table_consensus)
932 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table_consensus,
935 GNUNET_CONTAINER_multihashmap_destroy (neighbor->neighbor_table_consensus);
936 neighbor->neighbor_table_consensus = NULL;
938 if (NULL != neighbor->neighbor_table)
940 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table,
943 GNUNET_CONTAINER_multihashmap_destroy (neighbor->neighbor_table);
944 neighbor->neighbor_table = NULL;
946 if (GNUNET_SCHEDULER_NO_TASK != neighbor->consensus_task)
948 GNUNET_SCHEDULER_cancel (neighbor->consensus_task);
949 neighbor->consensus_task = GNUNET_SCHEDULER_NO_TASK;
951 if (NULL != neighbor->consensus)
953 GNUNET_CONSENSUS_destroy (neighbor->consensus);
954 neighbor->consensus = NULL;
960 * Function that is called with QoS information about an address; used
961 * to update our current distance to another peer.
964 * @param address the address
965 * @param active is this address in active use
966 * @param bandwidth_out assigned outbound bandwidth for the connection
967 * @param bandwidth_in assigned inbound bandwidth for the connection
968 * @param ats performance data for the address (as far as known)
969 * @param ats_count number of performance records in 'ats'
972 handle_ats_update (void *cls,
973 const struct GNUNET_HELLO_Address *address,
975 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out,
976 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
977 const struct GNUNET_ATS_Information *ats,
980 struct DirectNeighbor *neighbor;
983 if (GNUNET_NO == active)
985 distance = get_atsi_distance (ats, ats_count);
986 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
987 "ATS says distance to %s is %u\n",
988 GNUNET_i2s (&address->peer),
989 (unsigned int) distance);
990 /* check if entry exists */
991 neighbor = GNUNET_CONTAINER_multihashmap_get (direct_neighbors,
992 &address->peer.hashPubKey);
993 if (NULL != neighbor)
995 if ( (DIRECT_NEIGHBOR_COST == neighbor->distance) &&
996 (DIRECT_NEIGHBOR_COST == distance) )
997 return; /* no change */
998 if (DIRECT_NEIGHBOR_COST == neighbor->distance)
1000 neighbor->distance = distance;
1001 GNUNET_STATISTICS_update (stats,
1002 "# peers connected (1-hop)",
1004 handle_direct_disconnect (neighbor);
1005 GNUNET_CONTAINER_multihashmap_iterate (direct_neighbors,
1010 neighbor->distance = distance;
1011 if (DIRECT_NEIGHBOR_COST != neighbor->distance)
1013 if (GNUNET_YES != neighbor->connected)
1015 handle_direct_connect (neighbor);
1018 neighbor = GNUNET_malloc (sizeof (struct DirectNeighbor));
1019 neighbor->peer = address->peer;
1020 GNUNET_assert (GNUNET_YES ==
1021 GNUNET_CONTAINER_multihashmap_put (direct_neighbors,
1022 &address->peer.hashPubKey,
1024 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
1025 neighbor->connected = GNUNET_NO; /* not yet */
1026 neighbor->distance = distance;
1031 * Check if a target was removed from the set of the other peer; if so,
1032 * if we also used it for our route, we need to remove it from our
1033 * 'all_routes' set (and later check if an alternative path now exists).
1035 * @param cls the 'struct DirectNeighbor'
1036 * @param key peer identity for the target
1037 * @param value a 'struct Target' previously reachable via the given neighbor
1040 check_target_removed (void *cls,
1041 const struct GNUNET_HashCode *key,
1044 struct DirectNeighbor *neighbor = cls;
1045 struct Target *new_target;
1046 struct Route *current_route;
1048 new_target = GNUNET_CONTAINER_multihashmap_get (neighbor->neighbor_table_consensus,
1050 if (NULL == new_target)
1052 /* target was revoked, check if it was used */
1053 current_route = GNUNET_CONTAINER_multihashmap_get (all_routes,
1055 if ( (NULL == current_route) ||
1056 (current_route->next_hop != neighbor) )
1058 /* didn't matter, wasn't used */
1061 /* remove existing route */
1062 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1063 "Lost route to %s\n",
1064 GNUNET_i2s (¤t_route->target.peer));
1065 GNUNET_assert (GNUNET_YES ==
1066 GNUNET_CONTAINER_multihashmap_remove (all_routes, key, current_route));
1067 send_disconnect_to_plugin (¤t_route->target.peer);
1068 GNUNET_free (current_route);
1069 neighbor->target_removed = GNUNET_YES;
1077 * Check if a target was added to the set of the other peer; if it
1078 * was added or impoves the existing route, do the needed updates.
1080 * @param cls the 'struct DirectNeighbor'
1081 * @param key peer identity for the target
1082 * @param value a 'struct Target' now reachable via the given neighbor
1085 check_target_added (void *cls,
1086 const struct GNUNET_HashCode *key,
1089 struct DirectNeighbor *neighbor = cls;
1090 struct Target *target = value;
1091 struct Route *current_route;
1093 /* target was revoked, check if it was used */
1094 current_route = GNUNET_CONTAINER_multihashmap_get (all_routes,
1096 if (NULL != current_route)
1099 if (current_route->next_hop == neighbor)
1101 /* we had the same route before, no change */
1102 if (ntohl (target->distance) + 1 != ntohl (current_route->target.distance))
1104 current_route->target.distance = htonl (ntohl (target->distance) + 1);
1105 send_distance_change_to_plugin (&target->peer, ntohl (target->distance) + 1);
1109 if (ntohl (current_route->target.distance) >= ntohl (target->distance) + 1)
1111 /* alternative, shorter route exists, ignore */
1114 /* new route is better than the existing one, take over! */
1115 /* NOTE: minor security issue: malicious peers may advertise
1116 very short routes to take over longer paths; as we don't
1117 check that the shorter routes actually work, a malicious
1118 direct neighbor can use this to DoS our long routes */
1119 current_route->next_hop = neighbor;
1120 current_route->target.distance = htonl (ntohl (target->distance) + 1);
1121 send_distance_change_to_plugin (&target->peer, ntohl (target->distance) + 1);
1125 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1126 "Discovered new route to %s using %u hops\n",
1127 GNUNET_i2s (&target->peer),
1128 (unsigned int) (ntohl (target->distance) + 1));
1129 current_route = GNUNET_malloc (sizeof (struct Route));
1130 current_route->next_hop = neighbor;
1131 current_route->target.peer = target->peer;
1132 current_route->target.distance = htonl (ntohl (target->distance) + 1);
1133 GNUNET_assert (GNUNET_YES ==
1134 GNUNET_CONTAINER_multihashmap_put (all_routes,
1135 ¤t_route->target.peer.hashPubKey,
1137 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
1138 send_connect_to_plugin (¤t_route->target.peer,
1139 ntohl (current_route->target.distance));
1146 * The consensus has concluded, clean up and schedule the next one.
1148 * @param cls the 'struct GNUNET_DirectNeighbor' with which we created the consensus
1151 consensus_done_cb (void *cls)
1153 struct DirectNeighbor *neighbor = cls;
1155 GNUNET_CONSENSUS_destroy (neighbor->consensus);
1156 neighbor->consensus = NULL;
1157 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1158 "Finished consensus with %s!\n",
1159 GNUNET_i2s (&neighbor->peer));
1160 /* remove targets that disappeared */
1161 neighbor->target_removed = GNUNET_NO;
1162 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table,
1163 &check_target_removed,
1165 if (GNUNET_YES == neighbor->target_removed)
1167 /* check if we got an alternative for the removed routes */
1168 GNUNET_CONTAINER_multihashmap_iterate (direct_neighbors,
1172 /* add targets that appeared (and check for improved routes) */
1173 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table_consensus,
1174 &check_target_added,
1176 if (NULL != neighbor->neighbor_table)
1178 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table,
1181 GNUNET_CONTAINER_multihashmap_destroy (neighbor->neighbor_table);
1182 neighbor->neighbor_table = NULL;
1184 neighbor->neighbor_table = neighbor->neighbor_table_consensus;
1185 neighbor->neighbor_table_consensus = NULL;
1186 neighbor->consensus_task = GNUNET_SCHEDULER_add_delayed (GNUNET_DV_CONSENSUS_FREQUENCY,
1193 * We inserted the last element into the consensus, get ready to
1194 * insert the next element into the consensus or conclude if
1197 * @param cls the 'struct DirectNeighbor' of the peer we're building
1198 * a routing consensus with
1199 * @param success GNUNET_OK if the last element was added successfully,
1200 * GNUNET_SYSERR if we failed
1203 insert_next_element (void *cls,
1206 struct DirectNeighbor *neighbor = cls;
1207 struct GNUNET_CONSENSUS_Element element;
1209 while ( (DEFAULT_FISHEYE_DEPTH - 1 > neighbor->consensus_insertion_distance) &&
1210 (consensi[neighbor->consensus_insertion_distance].array_length == neighbor->consensus_insertion_offset) )
1212 neighbor->consensus_insertion_offset = 0;
1213 neighbor->consensus_insertion_distance++;
1214 /* skip over NULL entries */
1215 while ( (DEFAULT_FISHEYE_DEPTH - 1 > neighbor->consensus_insertion_distance) &&
1216 (consensi[neighbor->consensus_insertion_distance].array_length < neighbor->consensus_insertion_offset) &&
1217 (NULL == consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset]) )
1218 neighbor->consensus_insertion_offset++;
1220 if (DEFAULT_FISHEYE_DEPTH - 1 == neighbor->consensus_insertion_distance)
1222 /* we're done, conclude! */
1223 GNUNET_CONSENSUS_conclude (neighbor->consensus,
1224 GNUNET_DV_CONSENSUS_FREQUENCY,
1229 element.size = sizeof (struct Target);
1230 element.data = &consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset++]->target;
1232 /* skip over NULL entries */
1233 while ( (DEFAULT_FISHEYE_DEPTH - 1 > neighbor->consensus_insertion_distance) &&
1234 (consensi[neighbor->consensus_insertion_distance].array_length < neighbor->consensus_insertion_offset) &&
1235 (NULL == consensi[neighbor->consensus_insertion_distance].targets[neighbor->consensus_insertion_offset]) )
1236 neighbor->consensus_insertion_offset++;
1237 GNUNET_CONSENSUS_insert (neighbor->consensus,
1239 &insert_next_element,
1245 * We have learned a new route from the other peer. Add it to the
1246 * route set we're building.
1248 * @param cls the 'struct DirectNeighbor' we're building the consensus with
1249 * @param element the new element we have learned
1250 * @return GNUNET_OK if the valid is well-formed and should be added to the consensus,
1251 * GNUNET_SYSERR if the element should be ignored and not be propagated
1254 learn_route_cb (void *cls,
1255 const struct GNUNET_CONSENSUS_Element *element)
1257 struct DirectNeighbor *neighbor = cls;
1258 struct Target *target;
1260 if (NULL == element)
1262 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1263 "Failed to establish DV consensus, will try again later\n");
1264 GNUNET_CONSENSUS_destroy (neighbor->consensus);
1265 if (NULL != neighbor->neighbor_table_consensus)
1267 GNUNET_CONTAINER_multihashmap_iterate (neighbor->neighbor_table_consensus,
1270 GNUNET_CONTAINER_multihashmap_destroy (neighbor->neighbor_table_consensus);
1271 neighbor->neighbor_table_consensus = NULL;
1273 neighbor->consensus = NULL;
1274 neighbor->consensus_task = GNUNET_SCHEDULER_add_delayed (GNUNET_DV_CONSENSUS_FREQUENCY,
1277 return GNUNET_SYSERR;
1279 if (sizeof (struct Target) != element->size)
1281 GNUNET_break_op (0);
1282 return GNUNET_SYSERR;
1284 target = GNUNET_malloc (sizeof (struct Target));
1285 memcpy (target, element->data, sizeof (struct Target));
1287 GNUNET_CONTAINER_multihashmap_put (neighbor->neighbor_table_consensus,
1288 &target->peer.hashPubKey,
1290 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
1292 GNUNET_break_op (0);
1293 GNUNET_free (target);
1294 return GNUNET_SYSERR;
1301 * Start creating a new consensus from scratch.
1303 * @param cls the 'struct DirectNeighbor' of the peer we're building
1304 * a routing consensus with
1305 * @param tc scheduler context
1308 start_consensus (void *cls,
1309 const struct GNUNET_SCHEDULER_TaskContext *tc)
1311 struct DirectNeighbor *neighbor = cls;
1312 struct GNUNET_HashCode session_id;
1313 struct GNUNET_HashCode real_session_id;
1315 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1316 "Starting to create consensus with %s!\n",
1317 GNUNET_i2s (&neighbor->peer));
1318 neighbor->consensus_task = GNUNET_SCHEDULER_NO_TASK;
1319 neighbor->consensus_insertion_offset = 0;
1320 neighbor->consensus_insertion_distance = 0;
1321 GNUNET_assert (NULL == neighbor->neighbor_table_consensus);
1322 GNUNET_assert (NULL == neighbor->consensus);
1323 neighbor->neighbor_table_consensus = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_YES);
1324 /* construct session ID seed as XOR of both peer's identities */
1325 GNUNET_CRYPTO_hash_xor (&my_identity.hashPubKey,
1326 &neighbor->peer.hashPubKey,
1328 /* make sure session ID is unique across applications by salting it with 'DV' */
1329 GNUNET_CRYPTO_hkdf (&real_session_id, sizeof (real_session_id),
1330 GCRY_MD_SHA512, GCRY_MD_SHA256,
1332 &session_id, sizeof (session_id),
1334 neighbor->consensus = GNUNET_CONSENSUS_create (cfg,
1340 if (NULL == neighbor->consensus)
1342 neighbor->consensus_task = GNUNET_SCHEDULER_add_delayed (GNUNET_DV_CONSENSUS_FREQUENCY,
1347 insert_next_element (neighbor, GNUNET_OK);
1352 * Core handler for DV data messages. Whatever this message
1353 * contains all we really have to do is rip it out of its
1354 * DV layering and give it to our pal the DV plugin to report
1357 * @param cls closure
1358 * @param peer peer which sent the message (immediate sender)
1359 * @param message the message
1360 * @return GNUNET_OK on success, GNUNET_SYSERR if the other peer violated the protocol
1363 handle_dv_route_message (void *cls, const struct GNUNET_PeerIdentity *peer,
1364 const struct GNUNET_MessageHeader *message)
1366 const struct RouteMessage *rm;
1367 const struct GNUNET_MessageHeader *payload;
1368 struct Route *route;
1370 if (ntohs (message->size) < sizeof (struct RouteMessage) + sizeof (struct GNUNET_MessageHeader))
1372 GNUNET_break_op (0);
1373 return GNUNET_SYSERR;
1375 rm = (const struct RouteMessage *) message;
1376 payload = (const struct GNUNET_MessageHeader *) &rm[1];
1377 if (ntohs (message->size) != sizeof (struct RouteMessage) + ntohs (payload->size))
1379 GNUNET_break_op (0);
1380 return GNUNET_SYSERR;
1382 if (0 == memcmp (&rm->target,
1384 sizeof (struct GNUNET_PeerIdentity)))
1386 /* message is for me, check reverse route! */
1387 route = GNUNET_CONTAINER_multihashmap_get (all_routes,
1388 &rm->sender.hashPubKey);
1391 /* don't have reverse route, drop */
1392 GNUNET_STATISTICS_update (stats,
1393 "# message discarded (no reverse route)",
1397 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1398 "Delivering %u bytes to myself!\n",
1399 ntohs (payload->size));
1400 send_data_to_plugin (payload,
1402 ntohl (route->target.distance));
1405 route = GNUNET_CONTAINER_multihashmap_get (all_routes,
1406 &rm->target.hashPubKey);
1409 GNUNET_STATISTICS_update (stats,
1410 "# messages discarded (no route)",
1414 if (ntohl (route->target.distance) > ntohl (rm->distance) + 1)
1416 GNUNET_STATISTICS_update (stats,
1417 "# messages discarded (target too far)",
1421 forward_payload (route->next_hop,
1422 ntohl (route->target.distance),
1432 * Service server's handler for message send requests (which come
1433 * bubbling up to us through the DV plugin).
1435 * @param cls closure
1436 * @param client identification of the client
1437 * @param message the actual message
1440 handle_dv_send_message (void *cls, struct GNUNET_SERVER_Client *client,
1441 const struct GNUNET_MessageHeader *message)
1443 struct Route *route;
1444 const struct GNUNET_DV_SendMessage *msg;
1445 const struct GNUNET_MessageHeader *payload;
1447 if (ntohs (message->size) < sizeof (struct GNUNET_DV_SendMessage) + sizeof (struct GNUNET_MessageHeader))
1450 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1453 msg = (const struct GNUNET_DV_SendMessage *) message;
1454 GNUNET_break (0 != ntohl (msg->uid));
1455 payload = (const struct GNUNET_MessageHeader *) &msg[1];
1456 if (ntohs (message->size) != sizeof (struct GNUNET_DV_SendMessage) + ntohs (payload->size))
1459 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1462 route = GNUNET_CONTAINER_multihashmap_get (all_routes,
1463 &msg->target.hashPubKey);
1466 /* got disconnected */
1467 GNUNET_STATISTICS_update (stats,
1468 "# local messages discarded (no route)",
1470 send_ack_to_plugin (&msg->target, ntohl (msg->uid), GNUNET_YES);
1471 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1474 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1475 "Forwarding %u bytes to %s\n",
1476 ntohs (payload->size),
1477 GNUNET_i2s (&msg->target));
1479 forward_payload (route->next_hop,
1480 ntohl (route->target.distance),
1485 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1490 * Cleanup all of the data structures associated with a given neighbor.
1492 * @param neighbor neighbor to clean up
1495 cleanup_neighbor (struct DirectNeighbor *neighbor)
1497 struct PendingMessage *pending;
1499 while (NULL != (pending = neighbor->pm_head))
1501 neighbor->pm_queue_size--;
1502 GNUNET_CONTAINER_DLL_remove (neighbor->pm_head,
1505 GNUNET_free (pending);
1507 handle_direct_disconnect (neighbor);
1508 GNUNET_assert (GNUNET_YES ==
1509 GNUNET_CONTAINER_multihashmap_remove (direct_neighbors,
1510 &neighbor->peer.hashPubKey,
1512 GNUNET_free (neighbor);
1517 * Method called whenever a given peer disconnects.
1519 * @param cls closure
1520 * @param peer peer identity this notification is about
1523 handle_core_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
1525 struct DirectNeighbor *neighbor;
1527 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1528 "Received core peer disconnect message for peer `%s'!\n",
1530 /* Check for disconnect from self message */
1531 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
1534 GNUNET_CONTAINER_multihashmap_get (direct_neighbors, &peer->hashPubKey);
1535 if (NULL == neighbor)
1540 GNUNET_break (GNUNET_YES == neighbor->connected);
1541 neighbor->connected = GNUNET_NO;
1542 if (DIRECT_NEIGHBOR_COST == neighbor->distance)
1544 GNUNET_STATISTICS_update (stats,
1545 "# peers connected (1-hop)",
1548 cleanup_neighbor (neighbor);
1549 GNUNET_CONTAINER_multihashmap_iterate (direct_neighbors,
1556 * Multihashmap iterator for freeing routes. Should never be called.
1559 * @param key key value stored under
1560 * @param value the route to be freed
1562 * @return GNUNET_YES to continue iteration, GNUNET_NO to stop
1565 free_route (void *cls, const struct GNUNET_HashCode * key, void *value)
1567 struct Route *route = value;
1570 GNUNET_assert (GNUNET_YES ==
1571 GNUNET_CONTAINER_multihashmap_remove (all_routes, key, value));
1572 release_route (route);
1573 send_disconnect_to_plugin (&route->target.peer);
1574 GNUNET_free (route);
1580 * Multihashmap iterator for freeing direct neighbors. Should never be called.
1583 * @param key key value stored under
1584 * @param value the direct neighbor to be freed
1586 * @return GNUNET_YES to continue iteration, GNUNET_NO to stop
1589 free_direct_neighbors (void *cls, const struct GNUNET_HashCode * key, void *value)
1591 struct DirectNeighbor *neighbor = value;
1594 cleanup_neighbor (neighbor);
1600 * Task run during shutdown.
1606 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1610 GNUNET_CORE_disconnect (core_api);
1612 GNUNET_ATS_performance_done (ats);
1614 GNUNET_CONTAINER_multihashmap_iterate (direct_neighbors,
1615 &free_direct_neighbors, NULL);
1616 GNUNET_CONTAINER_multihashmap_iterate (all_routes,
1618 GNUNET_CONTAINER_multihashmap_destroy (direct_neighbors);
1619 GNUNET_CONTAINER_multihashmap_destroy (all_routes);
1620 GNUNET_STATISTICS_destroy (stats, GNUNET_NO);
1622 GNUNET_SERVER_notification_context_destroy (nc);
1624 for (i=0;i<DEFAULT_FISHEYE_DEPTH - 1;i++)
1625 GNUNET_array_grow (consensi[i].targets,
1626 consensi[i].array_length,
1632 * Notify newly connected client about an existing route.
1634 * @param cls the 'struct GNUNET_SERVER_Client'
1635 * @param key peer identity
1636 * @param value the XXX.
1637 * @return GNUNET_OK (continue to iterate)
1640 add_route (void *cls,
1641 const struct GNUNET_HashCode *key,
1644 struct GNUNET_SERVER_Client *client = cls;
1645 struct Route *route = value;
1646 struct GNUNET_DV_ConnectMessage cm;
1648 cm.header.size = htons (sizeof (cm));
1649 cm.header.type = htons (GNUNET_MESSAGE_TYPE_DV_CONNECT);
1650 cm.distance = htonl (route->target.distance);
1651 cm.peer = route->target.peer;
1653 GNUNET_SERVER_notification_context_unicast (nc,
1662 * Handle START-message. This is the first message sent to us
1663 * by the client (can only be one!).
1665 * @param cls closure (always NULL)
1666 * @param client identification of the client
1667 * @param message the actual message
1670 handle_start (void *cls, struct GNUNET_SERVER_Client *client,
1671 const struct GNUNET_MessageHeader *message)
1673 GNUNET_SERVER_notification_context_add (nc, client);
1674 GNUNET_SERVER_receive_done (client, GNUNET_OK);
1675 GNUNET_CONTAINER_multihashmap_iterate (all_routes,
1682 * Called on core init.
1685 * @param server legacy
1686 * @param identity this peer's identity
1689 core_init (void *cls, struct GNUNET_CORE_Handle *server,
1690 const struct GNUNET_PeerIdentity *identity)
1692 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1694 GNUNET_i2s (identity));
1695 my_identity = *identity;
1700 * Process dv requests.
1702 * @param cls closure
1703 * @param server the initialized server
1704 * @param c configuration to use
1707 run (void *cls, struct GNUNET_SERVER_Handle *server,
1708 const struct GNUNET_CONFIGURATION_Handle *c)
1710 static struct GNUNET_CORE_MessageHandler core_handlers[] = {
1711 {&handle_dv_route_message, GNUNET_MESSAGE_TYPE_DV_ROUTE, 0},
1714 static struct GNUNET_SERVER_MessageHandler plugin_handlers[] = {
1715 {&handle_start, NULL,
1716 GNUNET_MESSAGE_TYPE_DV_START,
1717 sizeof (struct GNUNET_MessageHeader) },
1718 { &handle_dv_send_message, NULL,
1719 GNUNET_MESSAGE_TYPE_DV_SEND,
1725 direct_neighbors = GNUNET_CONTAINER_multihashmap_create (128, GNUNET_NO);
1726 all_routes = GNUNET_CONTAINER_multihashmap_create (65536, GNUNET_NO);
1727 core_api = GNUNET_CORE_connect (cfg, NULL,
1729 &handle_core_connect,
1730 &handle_core_disconnect,
1735 if (NULL == core_api)
1737 ats = GNUNET_ATS_performance_init (cfg, &handle_ats_update, NULL);
1740 GNUNET_CORE_disconnect (core_api);
1743 nc = GNUNET_SERVER_notification_context_create (server,
1744 MAX_QUEUE_SIZE_PLUGIN);
1745 stats = GNUNET_STATISTICS_create ("dv", cfg);
1746 GNUNET_SERVER_add_handlers (server, plugin_handlers);
1747 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
1748 &shutdown_task, NULL);
1753 * The main function for the dv service.
1755 * @param argc number of arguments from the command line
1756 * @param argv command line arguments
1757 * @return 0 ok, 1 on error
1760 main (int argc, char *const *argv)
1762 return (GNUNET_OK ==
1763 GNUNET_SERVICE_run (argc, argv, "dv", GNUNET_SERVICE_OPTION_NONE,
1764 &run, NULL)) ? 0 : 1;
1767 /* end of gnunet-service-dv.c */