2 This file is part of GNUnet.
3 (C) 2001-2013 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.
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.
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 mesh/gnunet-service-mesh_connection.c
23 * @brief GNUnet MESH service connection handling
24 * @author Bartlomiej Polot
28 #include "gnunet_util_lib.h"
30 #include "gnunet_statistics_service.h"
32 #include "mesh_path.h"
33 #include "mesh_protocol.h"
35 #include "gnunet-service-mesh_connection.h"
36 #include "gnunet-service-mesh_peer.h"
37 #include "gnunet-service-mesh_tunnel.h"
40 #define LOG(level, ...) GNUNET_log_from (level,"mesh-con",__VA_ARGS__)
42 #define MESH_MAX_POLL_TIME GNUNET_TIME_relative_multiply (\
43 GNUNET_TIME_UNIT_MINUTES,\
48 /******************************************************************************/
49 /******************************** STRUCTS **********************************/
50 /******************************************************************************/
53 * Struct to encapsulate all the Flow Control information to a peer to which
54 * we are directly connected (on a core level).
56 struct MeshFlowControl
59 * Connection this controls.
61 struct MeshConnection *c;
64 * How many messages are in the queue on this connection.
69 * How many messages do we accept in the queue.
71 unsigned int queue_max;
79 * ID of the last packet sent towards the peer.
81 uint32_t last_pid_sent;
84 * ID of the last packet received from the peer.
86 uint32_t last_pid_recv;
89 * Last ACK sent to the peer (peer can't send more than this PID).
91 uint32_t last_ack_sent;
94 * Last ACK sent towards the origin (for traffic towards leaf node).
96 uint32_t last_ack_recv;
99 * Task to poll the peer in case of a lost ACK causes stall.
101 GNUNET_SCHEDULER_TaskIdentifier poll_task;
104 * How frequently to poll for ACKs.
106 struct GNUNET_TIME_Relative poll_time;
109 * Queued poll message, to cancel if not necessary anymore (got ACK).
111 struct MeshConnectionQueue *poll_msg;
114 * Queued poll message, to cancel if not necessary anymore (got ACK).
116 struct MeshConnectionQueue *ack_msg;
120 * Keep a record of the last messages sent on this connection.
122 struct MeshConnectionPerformance
125 * Circular buffer for storing measurements.
127 double usecsperbyte[AVG_MSGS];
130 * Running average of @c usecsperbyte.
135 * How many values of @c usecsperbyte are valid.
140 * Index of the next "free" position in @c usecsperbyte.
147 * Struct containing all information regarding a connection to a peer.
149 struct MeshConnection
152 * Tunnel this connection is part of.
154 struct MeshTunnel3 *t;
157 * Flow control information for traffic fwd.
159 struct MeshFlowControl fwd_fc;
162 * Flow control information for traffic bck.
164 struct MeshFlowControl bck_fc;
167 * Measure connection performance on the endpoint.
169 struct MeshConnectionPerformance *perf;
172 * ID of the connection.
174 struct GNUNET_HashCode id;
177 * State of the connection.
179 enum MeshConnectionState state;
182 * Path being used for the tunnel.
184 struct MeshPeerPath *path;
187 * Position of the local peer in the path.
189 unsigned int own_pos;
192 * Task to keep the used paths alive at the owner,
193 * time tunnel out on all the other peers.
195 GNUNET_SCHEDULER_TaskIdentifier fwd_maintenance_task;
198 * Task to keep the used paths alive at the destination,
199 * time tunnel out on all the other peers.
201 GNUNET_SCHEDULER_TaskIdentifier bck_maintenance_task;
204 * Pending message count.
206 int pending_messages;
209 * Destroy flag: if true, destroy on last message.
215 * Handle for messages queued but not yet sent.
217 struct MeshConnectionQueue
219 struct MeshPeerQueue *q;
224 /******************************************************************************/
225 /******************************* GLOBALS ***********************************/
226 /******************************************************************************/
229 * Global handle to the statistics service.
231 extern struct GNUNET_STATISTICS_Handle *stats;
234 * Local peer own ID (memory efficient handle).
236 extern GNUNET_PEER_Id myid;
239 * Local peer own ID (full value).
241 extern struct GNUNET_PeerIdentity my_full_id;
244 * Connections known, indexed by cid (MeshConnection).
246 static struct GNUNET_CONTAINER_MultiHashMap *connections;
249 * How many connections are we willing to maintain.
250 * Local connections are always allowed, even if there are more connections than max.
252 static unsigned long long max_connections;
255 * How many messages *in total* are we willing to queue, divide by number of
256 * connections to get connection queue size.
258 static unsigned long long max_msgs_queue;
261 * How often to send path keepalives. Paths timeout after 4 missed.
263 static struct GNUNET_TIME_Relative refresh_connection_time;
266 * How often to send path create / ACKs.
268 static struct GNUNET_TIME_Relative create_connection_time;
271 /******************************************************************************/
272 /******************************** STATIC ***********************************/
273 /******************************************************************************/
275 #if 0 // avoid compiler warning for unused static function
277 fc_debug (struct MeshFlowControl *fc)
279 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
280 fc->last_pid_recv, fc->last_ack_sent);
281 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
282 fc->last_pid_sent, fc->last_ack_recv);
283 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
284 fc->queue_n, fc->queue_max);
288 connection_debug (struct MeshConnection *c)
292 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CONNECTION ***\n");
295 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
296 peer2s (c->t->peer), GMC_2s (c));
297 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
298 c->state, c->pending_messages);
299 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
300 fc_debug (&c->fwd_fc);
301 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
302 fc_debug (&c->bck_fc);
307 * Get string description for tunnel state.
309 * @param s Tunnel state.
311 * @return String representation.
314 GMC_state2s (enum MeshConnectionState s)
318 case MESH_CONNECTION_NEW:
319 return "MESH_CONNECTION_NEW";
320 case MESH_CONNECTION_SENT:
321 return "MESH_CONNECTION_SENT";
322 case MESH_CONNECTION_ACK:
323 return "MESH_CONNECTION_ACK";
324 case MESH_CONNECTION_READY:
325 return "MESH_CONNECTION_READY";
327 return "MESH_CONNECTION_STATE_ERROR";
333 * Initialize a Flow Control structure to the initial state.
335 * @param fc Flow Control structure to initialize.
338 fc_init (struct MeshFlowControl *fc)
341 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
342 fc->last_pid_recv = (uint32_t) -1;
343 fc->last_ack_sent = (uint32_t) 0;
344 fc->last_ack_recv = (uint32_t) 0;
345 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
346 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
348 fc->queue_max = (max_msgs_queue / max_connections) + 1;
355 * @param cid Connection ID.
357 static struct MeshConnection *
358 connection_get (const struct GNUNET_HashCode *cid)
360 return GNUNET_CONTAINER_multihashmap_get (connections, cid);
365 connection_change_state (struct MeshConnection* c,
366 enum MeshConnectionState state)
368 LOG (GNUNET_ERROR_TYPE_DEBUG,
369 "Connection %s state was %s\n",
370 GMC_2s (c), GMC_state2s (c->state));
371 LOG (GNUNET_ERROR_TYPE_DEBUG,
372 "Connection %s state is now %s\n",
373 GMC_2s (c), GMC_state2s (state));
379 * Callback called when a queued ACK message is sent.
381 * @param cls Closure (FC).
382 * @param c Connection this message was on.
383 * @param q Queue handler this call invalidates.
384 * @param type Type of message sent.
385 * @param fwd Was this a FWD going message?
386 * @param size Size of the message.
390 struct MeshConnection *c,
391 struct MeshConnectionQueue *q,
392 uint16_t type, int fwd, size_t size)
394 struct MeshFlowControl *fc = cls;
401 * Send an ACK on the connection, informing the predecessor about
402 * the available buffer space. Should not be called in case the peer
403 * is origin (no predecessor) in the @c fwd direction.
405 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
406 * the ACK itself goes "back" (dest->root).
408 * @param c Connection on which to send the ACK.
409 * @param buffer How much space free to advertise?
410 * @param fwd Is this FWD ACK? (Going dest -> root)
411 * @param force Don't optimize out.
414 send_ack (struct MeshConnection *c, unsigned int buffer, int fwd, int force)
416 struct MeshFlowControl *next_fc;
417 struct MeshFlowControl *prev_fc;
418 struct GNUNET_MESH_ACK msg;
422 /* If origin, there is no connection to send ACKs. Wrong function! */
423 if (GMC_is_origin (c, fwd))
429 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
430 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
432 LOG (GNUNET_ERROR_TYPE_DEBUG,
433 "connection send %s ack on %s\n",
434 fwd ? "FWD" : "BCK", GMC_2s (c));
436 /* Check if we need to transmit the ACK. */
437 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
438 if (3 < delta && buffer < delta && GNUNET_NO == force)
440 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
441 LOG (GNUNET_ERROR_TYPE_DEBUG,
442 " last pid recv: %u, last ack sent: %u\n",
443 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
447 /* Ok, ACK might be necessary, what PID to ACK? */
448 ack = prev_fc->last_pid_recv + buffer;
449 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
450 LOG (GNUNET_ERROR_TYPE_DEBUG,
451 " last pid %u, last ack %u, qmax %u, q %u\n",
452 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
453 next_fc->queue_max, next_fc->queue_n);
454 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
456 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
460 /* Check if message is already in queue */
461 if (NULL != prev_fc->ack_msg)
463 if (GMC_is_pid_bigger (ack, prev_fc->last_ack_sent))
465 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
466 GMC_cancel (prev_fc->ack_msg);
467 /* GMC_cancel triggers ack_sent(), which clears fc->ack_msg */
471 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
476 prev_fc->last_ack_sent = ack;
478 /* Build ACK message and send on connection */
479 msg.header.size = htons (sizeof (msg));
480 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ACK);
481 msg.ack = htonl (ack);
484 prev_fc->ack_msg = GMC_send_prebuilt_message (&msg.header, c, !fwd,
490 * Callback called when a queued message is sent.
492 * Calculates the average time and connection packet tracking.
494 * @param cls Closure (ConnectionQueue Handle).
495 * @param c Connection this message was on.
496 * @param type Type of message sent.
497 * @param fwd Was this a FWD going message?
498 * @param size Size of the message.
499 * @param wait Time spent waiting for core (only the time for THIS message)
502 message_sent (void *cls,
503 struct MeshConnection *c, uint16_t type,
504 int fwd, size_t size,
505 struct GNUNET_TIME_Relative wait)
507 struct MeshConnectionPerformance *p;
508 struct MeshFlowControl *fc;
509 struct MeshConnectionQueue *q = cls;
512 fc = fwd ? &c->fwd_fc : &c->bck_fc;
513 LOG (GNUNET_ERROR_TYPE_DEBUG,
516 GNUNET_MESH_DEBUG_M2S (type));
517 LOG (GNUNET_ERROR_TYPE_DEBUG, "! C_P- %p %u\n", c, c->pending_messages);
522 LOG (GNUNET_ERROR_TYPE_DEBUG, "! calling cont\n");
523 q->cont (q->cont_cls, c, q, type, fwd, size);
527 c->pending_messages--;
528 if (GNUNET_YES == c->destroy && 0 == c->pending_messages)
530 LOG (GNUNET_ERROR_TYPE_DEBUG, "! destroying connection!\n");
534 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
537 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
539 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
541 LOG (GNUNET_ERROR_TYPE_DEBUG,
542 "! accounting pid %u\n",
544 GMC_send_ack (c, fwd, GNUNET_NO);
547 case GNUNET_MESSAGE_TYPE_MESH_POLL:
551 case GNUNET_MESSAGE_TYPE_MESH_ACK:
558 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
561 return; /* Only endpoints are interested in timing. */
564 usecsperbyte = ((double) wait.rel_value_us) / size;
565 if (p->size == AVG_MSGS)
567 /* Array is full. Substract oldest value, add new one and store. */
568 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
569 p->usecsperbyte[p->idx] = usecsperbyte;
570 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
574 /* Array not yet full. Add current value to avg and store. */
575 p->usecsperbyte[p->idx] = usecsperbyte;
577 p->avg += p->usecsperbyte[p->idx];
581 p->idx = (p->idx + 1) % AVG_MSGS;
586 * Get the previous hop in a connection
588 * @param c Connection.
590 * @return Previous peer in the connection.
592 static struct MeshPeer *
593 get_prev_hop (const struct MeshConnection *c)
597 LOG (GNUNET_ERROR_TYPE_DEBUG, "Get prev hop, own pos %u\n", c->own_pos);
598 if (0 == c->own_pos || c->path->length < 2)
599 id = c->path->peers[0];
601 id = c->path->peers[c->own_pos - 1];
603 return GMP_get_short (id);
608 * Get the next hop in a connection
610 * @param c Connection.
612 * @return Next peer in the connection.
614 static struct MeshPeer *
615 get_next_hop (const struct MeshConnection *c)
619 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
620 id = c->path->peers[c->path->length - 1];
622 id = c->path->peers[c->own_pos + 1];
624 return GMP_get_short (id);
629 * Get the hop in a connection.
631 * @param c Connection.
632 * @param fwd Next hop?
634 * @return Next peer in the connection.
636 static struct MeshPeer *
637 get_hop (struct MeshConnection *c, int fwd)
640 return get_next_hop (c);
641 return get_prev_hop (c);
646 * Is traffic coming from this sender 'FWD' traffic?
648 * @param c Connection to check.
649 * @param sender Peer identity of neighbor.
651 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
652 * the traffic is 'FWD'.
653 * #GNUNET_NO for BCK.
654 * #GNUNET_SYSERR for errors.
657 is_fwd (const struct MeshConnection *c,
658 const struct GNUNET_PeerIdentity *sender)
662 id = GNUNET_PEER_search (sender);
663 if (GMP_get_short_id (get_prev_hop (c)) == id)
666 if (GMP_get_short_id (get_next_hop (c)) == id)
670 return GNUNET_SYSERR;
675 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
676 * or a first CONNECTION_ACK directed to us.
678 * @param connection Connection to confirm.
679 * @param fwd Should we send it FWD? (root->dest)
680 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
683 send_connection_ack (struct MeshConnection *connection, int fwd)
685 struct MeshTunnel3 *t;
688 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection %s ACK\n",
689 !fwd ? "FWD" : "BCK");
690 GMP_queue_add (get_hop (connection, fwd), NULL,
691 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK,
692 sizeof (struct GNUNET_MESH_ConnectionACK),
693 connection, fwd, &message_sent, NULL);
694 connection->pending_messages++;
695 if (MESH_TUNNEL3_NEW == GMT_get_state (t))
696 GMT_change_state (t, MESH_TUNNEL3_WAITING);
697 if (MESH_CONNECTION_READY != connection->state)
698 connection_change_state (connection, MESH_CONNECTION_SENT);
703 * Send a notification that a connection is broken.
705 * @param c Connection that is broken.
706 * @param id1 Peer that has disconnected.
707 * @param id2 Peer that has disconnected.
708 * @param fwd Direction towards which to send it.
711 send_broken (struct MeshConnection *c,
712 const struct GNUNET_PeerIdentity *id1,
713 const struct GNUNET_PeerIdentity *id2,
716 struct GNUNET_MESH_ConnectionBroken msg;
718 msg.header.size = htons (sizeof (struct GNUNET_MESH_ConnectionBroken));
719 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN);
723 GMC_send_prebuilt_message (&msg.header, c, fwd, NULL, NULL);
729 * Send keepalive packets for a connection.
731 * @param c Connection to keep alive..
732 * @param fwd Is this a FWD keepalive? (owner -> dest).
735 connection_keepalive (struct MeshConnection *c, int fwd)
737 struct GNUNET_MESH_ConnectionKeepAlive *msg;
738 size_t size = sizeof (struct GNUNET_MESH_ConnectionKeepAlive);
742 type = fwd ? GNUNET_MESSAGE_TYPE_MESH_FWD_KEEPALIVE :
743 GNUNET_MESSAGE_TYPE_MESH_BCK_KEEPALIVE;
745 LOG (GNUNET_ERROR_TYPE_DEBUG,
746 "sending %s keepalive for connection %s]\n",
747 fwd ? "FWD" : "BCK", GMC_2s (c));
749 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) cbuf;
750 msg->header.size = htons (size);
751 msg->header.type = htons (type);
754 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
759 * Send CONNECTION_{CREATE/ACK} packets for a connection.
761 * @param c Connection for which to send the message.
762 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
765 connection_recreate (struct MeshConnection *c, int fwd)
767 LOG (GNUNET_ERROR_TYPE_DEBUG, "sending connection recreate\n");
771 send_connection_ack (c, GNUNET_NO);
776 * Generic connection timer management.
777 * Depending on the role of the peer in the connection will send the
778 * appropriate message (build or keepalive)
780 * @param c Conncetion to maintain.
784 connection_maintain (struct MeshConnection *c, int fwd)
786 if (MESH_TUNNEL3_SEARCHING == GMT_get_state (c->t))
788 /* TODO DHT GET with RO_BART */
793 case MESH_CONNECTION_NEW:
796 case MESH_CONNECTION_SENT:
797 connection_recreate (c, fwd);
799 case MESH_CONNECTION_READY:
800 connection_keepalive (c, fwd);
809 connection_fwd_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
811 struct MeshConnection *c = cls;
812 struct GNUNET_TIME_Relative delay;
814 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
815 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
818 connection_maintain (c, GNUNET_YES);
819 delay = c->state == MESH_CONNECTION_READY ?
820 refresh_connection_time : create_connection_time;
821 c->fwd_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
822 &connection_fwd_keepalive,
828 connection_bck_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
830 struct MeshConnection *c = cls;
831 struct GNUNET_TIME_Relative delay;
833 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
834 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
837 connection_maintain (c, GNUNET_NO);
838 delay = c->state == MESH_CONNECTION_READY ?
839 refresh_connection_time : create_connection_time;
840 c->bck_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
841 &connection_bck_keepalive,
847 * @brief Re-initiate traffic on this connection if necessary.
849 * Check if there is traffic queued towards this peer
850 * and the core transmit handle is NULL (traffic was stalled).
851 * If so, call core tmt rdy.
853 * @param c Connection on which initiate traffic.
854 * @param fwd Is this about fwd traffic?
857 connection_unlock_queue (struct MeshConnection *c, int fwd)
859 struct MeshPeer *peer;
861 LOG (GNUNET_ERROR_TYPE_DEBUG,
862 "connection_unlock_queue %s on %s\n",
863 fwd ? "FWD" : "BCK", GMC_2s (c));
865 if (GMC_is_terminal (c, fwd))
867 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal!\n");
871 peer = get_hop (c, fwd);
872 GMP_queue_unlock (peer, c);
877 * Cancel all transmissions that belong to a certain connection.
879 * If the connection is scheduled for destruction and no more messages are left,
880 * the connection will be destroyed by the continuation call.
882 * @param c Connection which to cancel. Might be destroyed during this call.
883 * @param fwd Cancel fwd traffic?
886 connection_cancel_queues (struct MeshConnection *c, int fwd)
888 struct MeshFlowControl *fc;
889 struct MeshPeer *peer;
897 fc = fwd ? &c->fwd_fc : &c->bck_fc;
898 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
900 GNUNET_SCHEDULER_cancel (fc->poll_task);
901 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
903 peer = get_hop (c, fwd);
904 GMP_queue_cancel (peer, c);
909 * Function called if a connection has been stalled for a while,
910 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
912 * @param cls Closure (poll ctx).
913 * @param tc TaskContext.
916 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
920 * Callback called when a queued POLL message is sent.
922 * @param cls Closure (FC).
923 * @param c Connection this message was on.
924 * @param q Queue handler this call invalidates.
925 * @param type Type of message sent.
926 * @param fwd Was this a FWD going message?
927 * @param size Size of the message.
930 poll_sent (void *cls,
931 struct MeshConnection *c,
932 struct MeshConnectionQueue *q,
933 uint16_t type, int fwd, size_t size)
935 struct MeshFlowControl *fc = cls;
937 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL sent, scheduling new one!\n");
939 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
940 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
941 &connection_poll, fc);
945 * Function called if a connection has been stalled for a while,
946 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
948 * @param cls Closure (poll ctx).
949 * @param tc TaskContext.
952 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
954 struct MeshFlowControl *fc = cls;
955 struct GNUNET_MESH_Poll msg;
956 struct MeshConnection *c;
958 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
959 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
965 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Polling!\n");
966 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** connection [%s]\n", GMC_2s (c));
967 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** %s\n",
968 fc == &c->fwd_fc ? "FWD" : "BCK");
970 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_POLL);
971 msg.header.size = htons (sizeof (msg));
972 msg.pid = htonl (fc->last_pid_sent);
973 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** last pid sent: %u!\n", fc->last_pid_sent);
974 fc->poll_msg = GMC_send_prebuilt_message (&msg.header, c, fc == &c->fwd_fc,
980 * Timeout function due to lack of keepalive/traffic from the owner.
981 * Destroys connection if called.
983 * @param cls Closure (connection to destroy).
984 * @param tc TaskContext.
987 connection_fwd_timeout (void *cls,
988 const struct GNUNET_SCHEDULER_TaskContext *tc)
990 struct MeshConnection *c = cls;
992 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
993 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
995 LOG (GNUNET_ERROR_TYPE_DEBUG,
996 "Connection %s[%X] FWD timed out. Destroying.\n",
1000 if (GMC_is_origin (c, GNUNET_YES)) /* If local, leave. */
1008 * Timeout function due to lack of keepalive/traffic from the destination.
1009 * Destroys connection if called.
1011 * @param cls Closure (connection to destroy).
1012 * @param tc TaskContext
1015 connection_bck_timeout (void *cls,
1016 const struct GNUNET_SCHEDULER_TaskContext *tc)
1018 struct MeshConnection *c = cls;
1020 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1021 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1024 LOG (GNUNET_ERROR_TYPE_DEBUG,
1025 "Connection %s[%X] FWD timed out. Destroying.\n",
1026 GMT_2s (c->t), c->id);
1028 if (GMC_is_origin (c, GNUNET_NO)) /* If local, leave. */
1036 * Resets the connection timeout task, some other message has done the
1038 * - For the first peer on the direction this means to send
1039 * a keepalive or a path confirmation message (either create or ACK).
1040 * - For all other peers, this means to destroy the connection,
1041 * due to lack of activity.
1042 * Starts the tiemout if no timeout was running (connection just created).
1044 * @param c Connection whose timeout to reset.
1045 * @param fwd Is this forward?
1047 * TODO use heap to improve efficiency of scheduler.
1050 connection_reset_timeout (struct MeshConnection *c, int fwd)
1052 GNUNET_SCHEDULER_TaskIdentifier *ti;
1053 GNUNET_SCHEDULER_Task f;
1055 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1057 if (GNUNET_SCHEDULER_NO_TASK != *ti)
1058 GNUNET_SCHEDULER_cancel (*ti);
1060 if (GMC_is_origin (c, fwd)) /* Startpoint */
1062 f = fwd ? &connection_fwd_keepalive : &connection_bck_keepalive;
1063 *ti = GNUNET_SCHEDULER_add_delayed (refresh_connection_time, f, c);
1065 else /* Relay, endpoint. */
1067 struct GNUNET_TIME_Relative delay;
1069 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1070 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1071 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1077 * Add the connection to the list of both neighbors.
1079 * @param c Connection.
1081 * @return #GNUNET_OK if everything went fine
1082 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1085 register_neighbors (struct MeshConnection *c)
1087 struct MeshPeer *next_peer;
1088 struct MeshPeer *prev_peer;
1090 next_peer = get_next_hop (c);
1091 prev_peer = get_prev_hop (c);
1093 if (GNUNET_NO == GMP_is_neighbor (next_peer)
1094 || GNUNET_NO == GMP_is_neighbor (prev_peer))
1095 return GNUNET_SYSERR;
1097 GMP_add_connection (next_peer, c);
1098 GMP_add_connection (prev_peer, c);
1105 * Remove the connection from the list of both neighbors.
1107 * @param c Connection.
1110 unregister_neighbors (struct MeshConnection *c)
1112 struct MeshPeer *peer;
1114 peer = get_next_hop (c);
1115 GMP_remove_connection (peer, c);
1117 peer = get_prev_hop (c);
1118 GMP_remove_connection (peer, c);
1124 * Bind the connection to the peer and the tunnel to that peer.
1126 * If the peer has no tunnel, create one. Update tunnel and connection
1127 * data structres to reflect new status.
1129 * @param c Connection.
1133 add_to_peer (struct MeshConnection *c, struct MeshPeer *peer)
1135 GMP_add_tunnel (peer);
1136 c->t = GMP_get_tunnel (peer);
1137 GMT_add_connection (c->t, c);
1140 /******************************************************************************/
1141 /******************************** API ***********************************/
1142 /******************************************************************************/
1145 * Core handler for connection creation.
1147 * @param cls Closure (unused).
1148 * @param peer Sender (neighbor).
1149 * @param message Message.
1151 * @return GNUNET_OK to keep the connection open,
1152 * GNUNET_SYSERR to close it (signal serious error)
1155 GMC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
1156 const struct GNUNET_MessageHeader *message)
1158 struct GNUNET_MESH_ConnectionCreate *msg;
1159 struct GNUNET_PeerIdentity *id;
1160 struct GNUNET_HashCode *cid;
1161 struct MeshPeerPath *path;
1162 struct MeshPeer *dest_peer;
1163 struct MeshPeer *orig_peer;
1164 struct MeshConnection *c;
1165 unsigned int own_pos;
1169 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1170 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection create msg\n");
1173 size = ntohs (message->size);
1174 if (size < sizeof (struct GNUNET_MESH_ConnectionCreate))
1176 GNUNET_break_op (0);
1180 /* Calculate hops */
1181 size -= sizeof (struct GNUNET_MESH_ConnectionCreate);
1182 if (size % sizeof (struct GNUNET_PeerIdentity))
1184 GNUNET_break_op (0);
1187 size /= sizeof (struct GNUNET_PeerIdentity);
1190 GNUNET_break_op (0);
1193 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1195 /* Get parameters */
1196 msg = (struct GNUNET_MESH_ConnectionCreate *) message;
1198 id = (struct GNUNET_PeerIdentity *) &msg[1];
1199 LOG (GNUNET_ERROR_TYPE_DEBUG,
1200 " connection %s (%s).\n",
1201 GNUNET_h2s (cid), GNUNET_i2s (id));
1203 /* Create connection */
1204 c = connection_get (cid);
1208 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating path...\n");
1209 path = path_new (size);
1211 for (i = 0; i < size; i++)
1213 LOG (GNUNET_ERROR_TYPE_DEBUG, " ... adding %s\n",
1214 GNUNET_i2s (&id[i]));
1215 path->peers[i] = GNUNET_PEER_intern (&id[i]);
1216 if (path->peers[i] == myid)
1219 if (own_pos == 0 && path->peers[own_pos] != myid)
1221 /* create path: self not found in path through self */
1222 GNUNET_break_op (0);
1223 path_destroy (path);
1226 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1227 GMP_add_path_to_all (path, GNUNET_NO);
1228 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1229 c = GMC_new (cid, NULL, path_duplicate (path), own_pos);
1232 path_destroy (path);
1235 connection_reset_timeout (c, GNUNET_YES);
1241 if (MESH_CONNECTION_NEW == c->state)
1242 connection_change_state (c, MESH_CONNECTION_SENT);
1244 /* Remember peers */
1245 dest_peer = GMP_get (&id[size - 1]);
1246 orig_peer = GMP_get (&id[0]);
1248 /* Is it a connection to us? */
1249 if (c->own_pos == size - 1)
1251 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1252 GMP_add_path_to_origin (orig_peer, path, GNUNET_YES);
1254 add_to_peer (c, orig_peer);
1255 if (MESH_TUNNEL3_NEW == GMT_get_state (c->t))
1256 GMT_change_state (c->t, MESH_TUNNEL3_WAITING);
1258 send_connection_ack (c, GNUNET_NO);
1259 if (MESH_CONNECTION_SENT == c->state)
1260 connection_change_state (c, MESH_CONNECTION_ACK);
1262 /* Keep tunnel alive in direction dest->owner*/
1263 c->bck_maintenance_task =
1264 GNUNET_SCHEDULER_add_delayed (create_connection_time,
1265 &connection_bck_keepalive, c);
1269 /* It's for somebody else! Retransmit. */
1270 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
1271 GMP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1272 GMP_add_path_to_origin (orig_peer, path, GNUNET_NO);
1273 GMC_send_prebuilt_message (message, c, GNUNET_YES, NULL, NULL);
1280 * Core handler for path confirmations.
1282 * @param cls closure
1283 * @param message message
1284 * @param peer peer identity this notification is about
1286 * @return GNUNET_OK to keep the connection open,
1287 * GNUNET_SYSERR to close it (signal serious error)
1290 GMC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
1291 const struct GNUNET_MessageHeader *message)
1293 struct GNUNET_MESH_ConnectionACK *msg;
1294 struct MeshConnection *c;
1295 struct MeshPeerPath *p;
1296 struct MeshPeer *pi;
1297 enum MeshConnectionState oldstate;
1300 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1301 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection ACK msg\n");
1302 msg = (struct GNUNET_MESH_ConnectionACK *) message;
1303 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n",
1304 GNUNET_h2s (&msg->cid));
1305 c = connection_get (&msg->cid);
1308 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1310 LOG (GNUNET_ERROR_TYPE_DEBUG, " don't know the connection!\n");
1314 oldstate = c->state;
1315 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
1316 pi = GMP_get (peer);
1317 if (get_next_hop (c) == pi)
1319 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
1321 if (MESH_CONNECTION_SENT == oldstate)
1322 connection_change_state (c, MESH_CONNECTION_ACK);
1324 else if (get_prev_hop (c) == pi)
1326 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK\n");
1328 connection_change_state (c, MESH_CONNECTION_READY);
1332 GNUNET_break_op (0);
1336 connection_reset_timeout (c, fwd);
1338 /* Add path to peers? */
1342 GMP_add_path_to_all (p, GNUNET_YES);
1349 /* Message for us as creator? */
1350 if (GMC_is_origin (c, GNUNET_YES))
1352 if (GNUNET_NO != fwd)
1354 GNUNET_break_op (0);
1357 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
1359 /* If just created, cancel the short timeout and start a long one */
1360 if (MESH_CONNECTION_SENT == oldstate)
1361 connection_reset_timeout (c, GNUNET_YES);
1363 /* Change connection and tunnel state */
1364 connection_change_state (c, MESH_CONNECTION_READY);
1365 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1366 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1368 /* Send ACK (~TCP ACK)*/
1369 send_connection_ack (c, GNUNET_YES);
1372 /* Message for us as destination? */
1373 if (GMC_is_terminal (c, GNUNET_YES))
1375 if (GNUNET_YES != fwd)
1377 GNUNET_break_op (0);
1380 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
1382 /* If just created, cancel the short timeout and start a long one */
1383 if (MESH_CONNECTION_ACK == oldstate)
1384 connection_reset_timeout (c, GNUNET_NO);
1386 /* Change tunnel state */
1387 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1388 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1393 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1394 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1400 * Core handler for notifications of broken paths
1402 * @param cls Closure (unused).
1403 * @param id Peer identity of sending neighbor.
1404 * @param message Message.
1406 * @return GNUNET_OK to keep the connection open,
1407 * GNUNET_SYSERR to close it (signal serious error)
1410 GMC_handle_broken (void* cls,
1411 const struct GNUNET_PeerIdentity* id,
1412 const struct GNUNET_MessageHeader* message)
1414 struct GNUNET_MESH_ConnectionBroken *msg;
1415 struct MeshConnection *c;
1418 LOG (GNUNET_ERROR_TYPE_DEBUG,
1419 "Received a CONNECTION BROKEN msg from %s\n", GNUNET_i2s (id));
1420 msg = (struct GNUNET_MESH_ConnectionBroken *) message;
1421 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1422 GNUNET_i2s (&msg->peer1));
1423 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1424 GNUNET_i2s (&msg->peer2));
1425 c = connection_get (&msg->cid);
1428 GNUNET_break_op (0);
1432 fwd = is_fwd (c, id);
1433 connection_cancel_queues (c, !fwd);
1434 if (GMC_is_terminal (c, fwd))
1436 if (0 < c->pending_messages)
1437 c->destroy = GNUNET_YES;
1443 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1444 c->destroy = GNUNET_YES;
1453 * Core handler for tunnel destruction
1455 * @param cls Closure (unused).
1456 * @param peer Peer identity of sending neighbor.
1457 * @param message Message.
1459 * @return GNUNET_OK to keep the connection open,
1460 * GNUNET_SYSERR to close it (signal serious error)
1463 GMC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
1464 const struct GNUNET_MessageHeader *message)
1466 struct GNUNET_MESH_ConnectionDestroy *msg;
1467 struct MeshConnection *c;
1470 msg = (struct GNUNET_MESH_ConnectionDestroy *) message;
1471 LOG (GNUNET_ERROR_TYPE_DEBUG,
1472 "Got a CONNECTION DESTROY message from %s\n",
1474 LOG (GNUNET_ERROR_TYPE_DEBUG,
1475 " for connection %s\n",
1476 GNUNET_h2s (&msg->cid));
1477 c = connection_get (&msg->cid);
1480 /* Probably already got the message from another path,
1481 * destroyed the tunnel and retransmitted to children.
1484 GNUNET_STATISTICS_update (stats, "# control on unknown tunnel",
1488 fwd = is_fwd (c, peer);
1489 if (GNUNET_SYSERR == fwd)
1491 GNUNET_break_op (0);
1494 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1495 c->destroy = GNUNET_YES;
1501 * Generic handler for mesh network encrypted traffic.
1503 * @param peer Peer identity this notification is about.
1504 * @param msg Encrypted message.
1506 * @return GNUNET_OK to keep the connection open,
1507 * GNUNET_SYSERR to close it (signal serious error)
1510 handle_mesh_encrypted (const struct GNUNET_PeerIdentity *peer,
1511 const struct GNUNET_MESH_Encrypted *msg)
1513 struct MeshConnection *c;
1514 struct MeshPeer *neighbor;
1515 struct MeshFlowControl *fc;
1516 GNUNET_PEER_Id peer_id;
1524 size = ntohs (msg->header.size);
1526 sizeof (struct GNUNET_MESH_Encrypted) +
1527 sizeof (struct GNUNET_MessageHeader))
1529 GNUNET_break_op (0);
1532 type = ntohs (msg->header.type);
1533 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1534 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message (#%u) from %s\n",
1535 GNUNET_MESH_DEBUG_M2S (type), ntohl (msg->pid), GNUNET_i2s (peer));
1537 /* Check connection */
1538 c = connection_get (&msg->cid);
1541 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1542 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING connection unknown\n");
1546 /* Check if origin is as expected */
1547 neighbor = get_prev_hop (c);
1548 peer_id = GNUNET_PEER_search (peer);
1549 if (peer_id == GMP_get_short_id (neighbor))
1555 neighbor = get_next_hop (c);
1556 if (peer_id == GMP_get_short_id (neighbor))
1562 /* Unexpected peer sending traffic on a connection. */
1563 GNUNET_break_op (0);
1569 fc = fwd ? &c->bck_fc : &c->fwd_fc;
1570 pid = ntohl (msg->pid);
1571 if (GMC_is_pid_bigger (pid, fc->last_ack_sent))
1573 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
1574 LOG (GNUNET_ERROR_TYPE_DEBUG,
1575 "WARNING Received PID %u, (prev %u), ACK %u\n",
1576 pid, fc->last_pid_recv, fc->last_ack_sent);
1579 if (GNUNET_NO == GMC_is_pid_bigger (pid, fc->last_pid_recv))
1581 GNUNET_STATISTICS_update (stats, "# duplicate PID", 1, GNUNET_NO);
1582 LOG (GNUNET_ERROR_TYPE_DEBUG,
1583 " Pid %u not expected (%u+), dropping!\n",
1584 pid, fc->last_pid_recv + 1);
1587 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1588 connection_change_state (c, MESH_CONNECTION_READY);
1589 connection_reset_timeout (c, fwd);
1590 fc->last_pid_recv = pid;
1592 /* Is this message for us? */
1593 if (GMC_is_terminal (c, fwd))
1595 /* TODO signature verification */
1596 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1597 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1604 fc->last_pid_recv = pid;
1605 GMT_handle_encrypted (c->t, msg);
1606 GMC_send_ack (c, fwd, GNUNET_NO);
1610 /* Message not for us: forward to next hop */
1611 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1612 ttl = ntohl (msg->ttl);
1613 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
1616 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
1617 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
1618 GMC_send_ack (c, fwd, GNUNET_NO);
1622 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1623 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
1629 * Generic handler for mesh network encrypted traffic.
1631 * @param peer Peer identity this notification is about.
1632 * @param msg Encrypted message.
1634 * @return GNUNET_OK to keep the connection open,
1635 * GNUNET_SYSERR to close it (signal serious error)
1638 handle_mesh_kx (const struct GNUNET_PeerIdentity *peer,
1639 const struct GNUNET_MESH_KX *msg)
1641 struct MeshConnection *c;
1642 struct MeshPeer *neighbor;
1643 GNUNET_PEER_Id peer_id;
1649 size = ntohs (msg->header.size);
1651 sizeof (struct GNUNET_MESH_Encrypted) +
1652 sizeof (struct GNUNET_MessageHeader))
1654 GNUNET_break_op (0);
1657 type = ntohs (msg->header.type);
1658 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1659 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message from %s\n",
1660 GNUNET_MESH_DEBUG_M2S (type), GNUNET_i2s (peer));
1662 /* Check connection */
1663 c = connection_get (&msg->cid);
1666 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1667 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING connection unknown\n");
1671 /* Check if origin is as expected */
1672 neighbor = get_prev_hop (c);
1673 peer_id = GNUNET_PEER_search (peer);
1674 if (peer_id == GMP_get_short_id (neighbor))
1680 neighbor = get_next_hop (c);
1681 if (peer_id == GMP_get_short_id (neighbor))
1687 /* Unexpected peer sending traffic on a connection. */
1688 GNUNET_break_op (0);
1693 /* Count as connection confirmation. */
1694 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1695 connection_change_state (c, MESH_CONNECTION_READY);
1696 connection_reset_timeout (c, fwd);
1699 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1700 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1703 /* Is this message for us? */
1704 if (GMC_is_terminal (c, fwd))
1706 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1707 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1713 GMT_handle_kx (c->t, &msg[1].header);
1717 /* Message not for us: forward to next hop */
1718 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1719 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1720 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
1727 * Core handler for encrypted mesh network traffic (channel mgmt, data).
1729 * @param cls Closure (unused).
1730 * @param message Message received.
1731 * @param peer Peer who sent the message.
1733 * @return GNUNET_OK to keep the connection open,
1734 * GNUNET_SYSERR to close it (signal serious error)
1737 GMC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
1738 const struct GNUNET_MessageHeader *message)
1740 return handle_mesh_encrypted (peer,
1741 (struct GNUNET_MESH_Encrypted *)message);
1746 * Core handler for key exchange traffic (ephemeral key, ping, pong).
1748 * @param cls Closure (unused).
1749 * @param message Message received.
1750 * @param peer Peer who sent the message.
1752 * @return GNUNET_OK to keep the connection open,
1753 * GNUNET_SYSERR to close it (signal serious error)
1756 GMC_handle_kx (void *cls, const struct GNUNET_PeerIdentity *peer,
1757 const struct GNUNET_MessageHeader *message)
1759 return handle_mesh_kx (peer,
1760 (struct GNUNET_MESH_KX *) message);
1765 * Core handler for mesh network traffic point-to-point acks.
1767 * @param cls closure
1768 * @param message message
1769 * @param peer peer identity this notification is about
1771 * @return GNUNET_OK to keep the connection open,
1772 * GNUNET_SYSERR to close it (signal serious error)
1775 GMC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
1776 const struct GNUNET_MessageHeader *message)
1778 struct GNUNET_MESH_ACK *msg;
1779 struct MeshConnection *c;
1780 struct MeshFlowControl *fc;
1785 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1786 LOG (GNUNET_ERROR_TYPE_DEBUG, "Got an ACK packet from %s!\n",
1788 msg = (struct GNUNET_MESH_ACK *) message;
1790 c = connection_get (&msg->cid);
1794 GNUNET_STATISTICS_update (stats, "# ack on unknown connection", 1,
1799 /* Is this a forward or backward ACK? */
1800 id = GNUNET_PEER_search (peer);
1801 if (GMP_get_short_id (get_next_hop (c)) == id)
1803 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
1807 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1809 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
1815 GNUNET_break_op (0);
1819 ack = ntohl (msg->ack);
1820 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u (was %u)\n",
1821 ack, fc->last_ack_recv);
1822 if (GMC_is_pid_bigger (ack, fc->last_ack_recv))
1823 fc->last_ack_recv = ack;
1825 /* Cancel polling if the ACK is big enough. */
1826 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task &&
1827 GMC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
1829 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
1830 GNUNET_SCHEDULER_cancel (fc->poll_task);
1831 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1832 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
1835 connection_unlock_queue (c, fwd);
1842 * Core handler for mesh network traffic point-to-point ack polls.
1844 * @param cls closure
1845 * @param message message
1846 * @param peer peer identity this notification is about
1848 * @return GNUNET_OK to keep the connection open,
1849 * GNUNET_SYSERR to close it (signal serious error)
1852 GMC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
1853 const struct GNUNET_MessageHeader *message)
1855 struct GNUNET_MESH_Poll *msg;
1856 struct MeshConnection *c;
1857 struct MeshFlowControl *fc;
1862 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1863 LOG (GNUNET_ERROR_TYPE_DEBUG,
1864 "Got a POLL packet from %s!\n",
1867 msg = (struct GNUNET_MESH_Poll *) message;
1869 c = connection_get (&msg->cid);
1873 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
1875 GNUNET_break_op (0);
1879 /* Is this a forward or backward ACK?
1880 * Note: a poll should never be needed in a loopback case,
1881 * since there is no possiblility of packet loss there, so
1882 * this way of discerining FWD/BCK should not be a problem.
1884 id = GNUNET_PEER_search (peer);
1885 if (GMP_get_short_id (get_next_hop (c)) == id)
1887 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
1890 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1892 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
1897 GNUNET_break_op (0);
1901 pid = ntohl (msg->pid);
1902 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
1903 fc->last_pid_recv = pid;
1904 fwd = fc == &c->bck_fc;
1905 GMC_send_ack (c, fwd, GNUNET_YES);
1912 * Core handler for mesh keepalives.
1914 * @param cls closure
1915 * @param message message
1916 * @param peer peer identity this notification is about
1917 * @return GNUNET_OK to keep the connection open,
1918 * GNUNET_SYSERR to close it (signal serious error)
1920 * TODO: Check who we got this from, to validate route.
1923 GMC_handle_keepalive (void *cls, const struct GNUNET_PeerIdentity *peer,
1924 const struct GNUNET_MessageHeader *message)
1926 struct GNUNET_MESH_ConnectionKeepAlive *msg;
1927 struct MeshConnection *c;
1928 struct MeshPeer *neighbor;
1931 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) message;
1932 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a keepalive packet from %s\n",
1935 c = connection_get (&msg->cid);
1938 GNUNET_STATISTICS_update (stats, "# keepalive on unknown connection", 1,
1943 fwd = GNUNET_MESSAGE_TYPE_MESH_FWD_KEEPALIVE == ntohs (message->type) ?
1944 GNUNET_YES : GNUNET_NO;
1946 /* Check if origin is as expected */
1947 neighbor = get_hop (c, fwd);
1948 if (GNUNET_PEER_search (peer) != GMP_get_short_id (neighbor))
1950 GNUNET_break_op (0);
1954 connection_change_state (c, MESH_CONNECTION_READY);
1955 connection_reset_timeout (c, fwd);
1957 if (GMC_is_terminal (c, fwd))
1960 GNUNET_STATISTICS_update (stats, "# keepalives forwarded", 1, GNUNET_NO);
1961 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1968 * Send an ACK on the appropriate connection/channel, depending on
1969 * the direction and the position of the peer.
1971 * @param c Which connection to send the hop-by-hop ACK.
1972 * @param fwd Is this a fwd ACK? (will go dest->root).
1973 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
1976 GMC_send_ack (struct MeshConnection *c, int fwd, int force)
1978 unsigned int buffer;
1980 LOG (GNUNET_ERROR_TYPE_DEBUG,
1981 "GMC send %s ACK on %s\n",
1982 fwd ? "FWD" : "BCK", GMC_2s (c));
1990 /* Get available buffer space */
1991 if (GMC_is_terminal (c, fwd))
1993 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
1994 buffer = GMT_get_channels_buffer (c->t);
1998 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
1999 buffer = GMC_get_buffer (c, fwd);
2001 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2002 if (0 == buffer && GNUNET_NO == force)
2005 /* Send available buffer space */
2006 if (GMC_is_origin (c, fwd))
2008 GNUNET_assert (NULL != c->t);
2009 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2010 GMT_unchoke_channels (c->t);
2014 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2015 send_ack (c, buffer, fwd, force);
2021 * Initialize the connections subsystem
2023 * @param c Configuration handle.
2026 GMC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2028 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2030 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_MSGS_QUEUE",
2033 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2034 "MESH", "MAX_MSGS_QUEUE", "MISSING");
2035 GNUNET_SCHEDULER_shutdown ();
2040 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_CONNECTIONS",
2043 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2044 "MESH", "MAX_CONNECTIONS", "MISSING");
2045 GNUNET_SCHEDULER_shutdown ();
2050 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REFRESH_CONNECTION_TIME",
2051 &refresh_connection_time))
2053 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2054 "MESH", "REFRESH_CONNECTION_TIME", "MISSING");
2055 GNUNET_SCHEDULER_shutdown ();
2058 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2059 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_YES);
2063 * Shut down the connections subsystem.
2068 GNUNET_CONTAINER_multihashmap_destroy (connections);
2072 struct MeshConnection *
2073 GMC_new (const struct GNUNET_HashCode *cid,
2074 struct MeshTunnel3 *t,
2075 struct MeshPeerPath *p,
2076 unsigned int own_pos)
2078 struct MeshConnection *c;
2080 c = GNUNET_new (struct MeshConnection);
2082 GNUNET_CONTAINER_multihashmap_put (connections, &c->id, c,
2083 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST);
2084 fc_init (&c->fwd_fc);
2085 fc_init (&c->bck_fc);
2090 if (own_pos > p->length - 1)
2097 c->own_pos = own_pos;
2102 c->fwd_maintenance_task =
2103 GNUNET_SCHEDULER_add_delayed (create_connection_time,
2104 &connection_fwd_keepalive, c);
2106 if (GNUNET_OK != register_neighbors (c))
2117 GMC_destroy (struct MeshConnection *c)
2122 if (2 == c->destroy) /* cancel queues -> GMP_queue_cancel -> q_destroy -> */
2123 return; /* -> message_sent -> GMC_destroy. Don't loop. */
2126 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying connection %s\n", GMC_2s (c));
2128 /* Cancel all traffic */
2129 connection_cancel_queues (c, GNUNET_YES);
2130 connection_cancel_queues (c, GNUNET_NO);
2132 /* Cancel maintainance task (keepalive/timeout) */
2133 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_maintenance_task)
2134 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2135 if (GNUNET_SCHEDULER_NO_TASK != c->bck_maintenance_task)
2136 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2138 /* Unregister from neighbors */
2139 unregister_neighbors (c);
2142 GNUNET_STATISTICS_update (stats, "# connections", -1, GNUNET_NO);
2144 GMT_remove_connection (c->t, c);
2146 if (GNUNET_NO == GMC_is_origin (c, GNUNET_YES))
2147 path_destroy (c->path);
2149 GNUNET_break (GNUNET_YES ==
2150 GNUNET_CONTAINER_multihashmap_remove (connections, &c->id, c));
2156 * Get the connection ID.
2158 * @param c Connection to get the ID from.
2160 * @return ID of the connection.
2162 const struct GNUNET_HashCode *
2163 GMC_get_id (const struct MeshConnection *c)
2170 * Get the connection path.
2172 * @param c Connection to get the path from.
2174 * @return path used by the connection.
2176 const struct MeshPeerPath *
2177 GMC_get_path (const struct MeshConnection *c)
2184 * Get the connection state.
2186 * @param c Connection to get the state from.
2188 * @return state of the connection.
2190 enum MeshConnectionState
2191 GMC_get_state (const struct MeshConnection *c)
2197 * Get the connection tunnel.
2199 * @param c Connection to get the tunnel from.
2201 * @return tunnel of the connection.
2203 struct MeshTunnel3 *
2204 GMC_get_tunnel (const struct MeshConnection *c)
2211 * Get free buffer space in a connection.
2213 * @param c Connection.
2214 * @param fwd Is query about FWD traffic?
2216 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2219 GMC_get_buffer (struct MeshConnection *c, int fwd)
2221 struct MeshFlowControl *fc;
2223 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2225 return (fc->queue_max - fc->queue_n);
2229 * Get how many messages have we allowed to send to us from a direction.
2231 * @param c Connection.
2232 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2234 * @return last_ack_sent - last_pid_recv
2237 GMC_get_allowed (struct MeshConnection *c, int fwd)
2239 struct MeshFlowControl *fc;
2241 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2242 if (GMC_is_pid_bigger(fc->last_pid_recv, fc->last_ack_sent))
2246 return (fc->last_ack_sent - fc->last_pid_recv);
2250 * Get messages queued in a connection.
2252 * @param c Connection.
2253 * @param fwd Is query about FWD traffic?
2255 * @return Number of messages queued.
2258 GMC_get_qn (struct MeshConnection *c, int fwd)
2260 struct MeshFlowControl *fc;
2262 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2269 * Allow the connection to advertise a buffer of the given size.
2271 * The connection will send an @c fwd ACK message (so: in direction !fwd)
2272 * allowing up to last_pid_recv + buffer.
2274 * @param c Connection.
2275 * @param buffer How many more messages the connection can accept.
2276 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
2279 GMC_allow (struct MeshConnection *c, unsigned int buffer, int fwd)
2281 send_ack (c, buffer, fwd, GNUNET_NO);
2286 * Notify other peers on a connection of a broken link. Mark connections
2287 * to destroy after all traffic has been sent.
2289 * @param c Connection on which there has been a disconnection.
2290 * @param peer Peer that disconnected.
2293 GMC_notify_broken (struct MeshConnection *c,
2294 struct MeshPeer *peer)
2298 LOG (GNUNET_ERROR_TYPE_DEBUG,
2299 " notify broken on %s due to %s disconnect\n",
2300 GMC_2s (c), GMP_2s (peer));
2302 fwd = peer == get_prev_hop (c);
2304 if (GNUNET_YES == GMC_is_terminal (c, fwd))
2306 /* Local shutdown, no one to notify about this. */
2310 if (GNUNET_NO == c->destroy)
2311 send_broken (c, &my_full_id, GMP_get_id (peer), fwd);
2313 /* Connection will have at least one pending message
2314 * (the one we just scheduled), so no point in checking whether to
2315 * destroy immediately. */
2316 c->destroy = GNUNET_YES;
2319 * Cancel all queues, if no message is left, connection will be destroyed.
2321 connection_cancel_queues (c, !fwd);
2328 * Is this peer the first one on the connection?
2330 * @param c Connection.
2331 * @param fwd Is this about fwd traffic?
2333 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
2336 GMC_is_origin (struct MeshConnection *c, int fwd)
2338 if (!fwd && c->path->length - 1 == c->own_pos )
2340 if (fwd && 0 == c->own_pos)
2347 * Is this peer the last one on the connection?
2349 * @param c Connection.
2350 * @param fwd Is this about fwd traffic?
2351 * Note that the ROOT is the terminal for BCK traffic!
2353 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
2356 GMC_is_terminal (struct MeshConnection *c, int fwd)
2358 return GMC_is_origin (c, !fwd);
2363 * See if we are allowed to send by the next hop in the given direction.
2365 * @param c Connection.
2366 * @param fwd Is this about fwd traffic?
2368 * @return #GNUNET_YES in case it's OK to send.
2371 GMC_is_sendable (struct MeshConnection *c, int fwd)
2373 struct MeshFlowControl *fc;
2375 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2376 if (GMC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2382 * Sends an already built message on a connection, properly registering
2383 * all used resources.
2385 * @param message Message to send. Function makes a copy of it.
2386 * If message is not hop-by-hop, decrements TTL of copy.
2387 * @param c Connection on which this message is transmitted.
2388 * @param fwd Is this a fwd message?
2389 * @param cont Continuation called once message is sent. Can be NULL.
2390 * @param cont_cls Closure for @c cont.
2392 * @return Handle to cancel the message before it's sent. NULL on error.
2393 * Invalid on @c cont call.
2395 struct MeshConnectionQueue *
2396 GMC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2397 struct MeshConnection *c, int fwd,
2398 GMC_sent cont, void *cont_cls)
2400 struct MeshFlowControl *fc;
2401 struct MeshConnectionQueue *q;
2407 size = ntohs (message->size);
2408 data = GNUNET_malloc (size);
2409 memcpy (data, message, size);
2410 type = ntohs (message->type);
2411 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send %s (%u bytes) on connection %s\n",
2412 GNUNET_MESH_DEBUG_M2S (type), size, GMC_2s (c));
2414 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2415 droppable = GNUNET_YES;
2418 struct GNUNET_MESH_Encrypted *emsg;
2419 struct GNUNET_MESH_KX *kmsg;
2420 struct GNUNET_MESH_ACK *amsg;
2421 struct GNUNET_MESH_Poll *pmsg;
2422 struct GNUNET_MESH_ConnectionDestroy *dmsg;
2423 struct GNUNET_MESH_ConnectionBroken *bmsg;
2426 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
2427 emsg = (struct GNUNET_MESH_Encrypted *) data;
2428 ttl = ntohl (emsg->ttl);
2431 GNUNET_break_op (0);
2436 emsg->ttl = htonl (ttl - 1);
2437 emsg->pid = htonl (fc->next_pid++);
2438 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
2440 LOG (GNUNET_ERROR_TYPE_DEBUG, "pid %u\n", ntohl (emsg->pid));
2441 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
2442 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
2443 if (GMC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
2445 GMC_start_poll (c, fwd);
2449 case GNUNET_MESSAGE_TYPE_MESH_KX:
2450 kmsg = (struct GNUNET_MESH_KX *) data;
2454 case GNUNET_MESSAGE_TYPE_MESH_ACK:
2455 amsg = (struct GNUNET_MESH_ACK *) data;
2457 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
2458 droppable = GNUNET_NO;
2461 case GNUNET_MESSAGE_TYPE_MESH_POLL:
2462 pmsg = (struct GNUNET_MESH_Poll *) data;
2464 LOG (GNUNET_ERROR_TYPE_DEBUG, " poll %u\n", ntohl (pmsg->pid));
2465 droppable = GNUNET_NO;
2468 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY:
2469 dmsg = (struct GNUNET_MESH_ConnectionDestroy *) data;
2474 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN:
2475 bmsg = (struct GNUNET_MESH_ConnectionBroken *) data;
2480 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE:
2481 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK:
2488 if (fc->queue_n > fc->queue_max && droppable)
2490 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
2493 LOG (GNUNET_ERROR_TYPE_DEBUG,
2494 "queue full: %u/%u\n",
2495 fc->queue_n, fc->queue_max);
2496 if (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED == type)
2502 return NULL; /* Drop this message */
2505 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u\n", c, c->pending_messages);
2506 c->pending_messages++;
2508 q = GNUNET_new (struct MeshConnectionQueue);
2509 q->q = GMP_queue_add (get_hop (c, fwd), data, type, size, c, fwd,
2519 q->cont_cls = cont_cls;
2525 * Cancel a previously sent message while it's in the queue.
2527 * ONLY can be called before the continuation given to the send function
2528 * is called. Once the continuation is called, the message is no longer in the
2531 * If the send function was given no continuation, GMC_cancel should
2532 * NOT be called, since it's not possible to determine if the message has
2533 * already been sent.
2535 * @param q Handle to the queue.
2538 GMC_cancel (struct MeshConnectionQueue *q)
2540 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GMC cancel message\n");
2542 /* queue destroy calls message_sent, which calls q->cont and frees q */
2543 GMP_queue_destroy (q->q, GNUNET_YES);
2548 * Sends a CREATE CONNECTION message for a path to a peer.
2549 * Changes the connection and tunnel states if necessary.
2551 * @param connection Connection to create.
2554 GMC_send_create (struct MeshConnection *connection)
2556 enum MeshTunnel3State state;
2559 size = sizeof (struct GNUNET_MESH_ConnectionCreate);
2560 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
2561 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection create\n");
2562 GMP_queue_add (get_next_hop (connection), NULL,
2563 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE,
2564 size, connection, GNUNET_YES, &message_sent, NULL);
2565 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
2566 connection, connection->pending_messages);
2567 connection->pending_messages++;
2568 state = GMT_get_state (connection->t);
2569 if (MESH_TUNNEL3_SEARCHING == state || MESH_TUNNEL3_NEW == state)
2570 GMT_change_state (connection->t, MESH_TUNNEL3_WAITING);
2571 if (MESH_CONNECTION_NEW == connection->state)
2572 connection_change_state (connection, MESH_CONNECTION_SENT);
2577 * Send a message to all peers in this connection that the connection
2578 * is no longer valid.
2580 * If some peer should not receive the message, it should be zero'ed out
2581 * before calling this function.
2583 * @param c The connection whose peers to notify.
2586 GMC_send_destroy (struct MeshConnection *c)
2588 struct GNUNET_MESH_ConnectionDestroy msg;
2590 if (GNUNET_YES == c->destroy)
2593 msg.header.size = htons (sizeof (msg));
2594 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY);;
2596 LOG (GNUNET_ERROR_TYPE_DEBUG,
2597 " sending connection destroy for connection %s\n",
2600 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_YES))
2601 GMC_send_prebuilt_message (&msg.header, c, GNUNET_YES, NULL, NULL);
2602 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_NO))
2603 GMC_send_prebuilt_message (&msg.header, c, GNUNET_NO, NULL, NULL);
2604 c->destroy = GNUNET_YES;
2609 * @brief Start a polling timer for the connection.
2611 * When a neighbor does not accept more traffic on the connection it could be
2612 * caused by a simple congestion or by a lost ACK. Polling enables to check
2613 * for the lastest ACK status for a connection.
2615 * @param c Connection.
2616 * @param fwd Should we poll in the FWD direction?
2619 GMC_start_poll (struct MeshConnection *c, int fwd)
2621 struct MeshFlowControl *fc;
2623 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2624 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task && NULL != fc->poll_msg)
2628 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
2635 * @brief Stop polling a connection for ACKs.
2637 * Once we have enough ACKs for future traffic, polls are no longer necessary.
2639 * @param c Connection.
2640 * @param fwd Should we stop the poll in the FWD direction?
2643 GMC_stop_poll (struct MeshConnection *c, int fwd)
2645 struct MeshFlowControl *fc;
2647 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2648 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
2650 GNUNET_SCHEDULER_cancel (fc->poll_task);
2651 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2656 * Get a (static) string for a connection.
2658 * @param c Connection.
2661 GMC_2s (struct MeshConnection *c)
2665 static char buf[128];
2667 sprintf (buf, "%s (->%s)", GNUNET_h2s (&c->id), GMT_2s (c->t));
2670 return GNUNET_h2s (&c->id);