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.
1082 register_neighbors (struct MeshConnection *c)
1084 struct MeshPeer *peer;
1086 peer = get_next_hop (c);
1087 if (GNUNET_NO == GMP_is_neighbor (peer))
1092 GMP_add_connection (peer, c);
1093 peer = get_prev_hop (c);
1094 if (GNUNET_NO == GMP_is_neighbor (peer))
1099 GMP_add_connection (peer, c);
1104 * Remove the connection from the list of both neighbors.
1106 * @param c Connection.
1109 unregister_neighbors (struct MeshConnection *c)
1111 struct MeshPeer *peer;
1113 peer = get_next_hop (c);
1114 GMP_remove_connection (peer, c);
1116 peer = get_prev_hop (c);
1117 GMP_remove_connection (peer, c);
1123 * Bind the connection to the peer and the tunnel to that peer.
1125 * If the peer has no tunnel, create one. Update tunnel and connection
1126 * data structres to reflect new status.
1128 * @param c Connection.
1132 add_to_peer (struct MeshConnection *c, struct MeshPeer *peer)
1134 GMP_add_tunnel (peer);
1135 c->t = GMP_get_tunnel (peer);
1136 GMT_add_connection (c->t, c);
1139 /******************************************************************************/
1140 /******************************** API ***********************************/
1141 /******************************************************************************/
1144 * Core handler for connection creation.
1146 * @param cls Closure (unused).
1147 * @param peer Sender (neighbor).
1148 * @param message Message.
1150 * @return GNUNET_OK to keep the connection open,
1151 * GNUNET_SYSERR to close it (signal serious error)
1154 GMC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
1155 const struct GNUNET_MessageHeader *message)
1157 struct GNUNET_MESH_ConnectionCreate *msg;
1158 struct GNUNET_PeerIdentity *id;
1159 struct GNUNET_HashCode *cid;
1160 struct MeshPeerPath *path;
1161 struct MeshPeer *dest_peer;
1162 struct MeshPeer *orig_peer;
1163 struct MeshConnection *c;
1164 unsigned int own_pos;
1168 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1169 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection create msg\n");
1172 size = ntohs (message->size);
1173 if (size < sizeof (struct GNUNET_MESH_ConnectionCreate))
1175 GNUNET_break_op (0);
1179 /* Calculate hops */
1180 size -= sizeof (struct GNUNET_MESH_ConnectionCreate);
1181 if (size % sizeof (struct GNUNET_PeerIdentity))
1183 GNUNET_break_op (0);
1186 size /= sizeof (struct GNUNET_PeerIdentity);
1189 GNUNET_break_op (0);
1192 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1194 /* Get parameters */
1195 msg = (struct GNUNET_MESH_ConnectionCreate *) message;
1197 id = (struct GNUNET_PeerIdentity *) &msg[1];
1198 LOG (GNUNET_ERROR_TYPE_DEBUG,
1199 " connection %s (%s).\n",
1200 GNUNET_h2s (cid), GNUNET_i2s (id));
1202 /* Create connection */
1203 c = connection_get (cid);
1207 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating path...\n");
1208 path = path_new (size);
1210 for (i = 0; i < size; i++)
1212 LOG (GNUNET_ERROR_TYPE_DEBUG, " ... adding %s\n",
1213 GNUNET_i2s (&id[i]));
1214 path->peers[i] = GNUNET_PEER_intern (&id[i]);
1215 if (path->peers[i] == myid)
1218 if (own_pos == 0 && path->peers[own_pos] != myid)
1220 /* create path: self not found in path through self */
1221 GNUNET_break_op (0);
1222 path_destroy (path);
1225 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1226 GMP_add_path_to_all (path, GNUNET_NO);
1227 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1228 c = GMC_new (cid, NULL, path_duplicate (path), own_pos);
1231 path_destroy (path);
1234 connection_reset_timeout (c, GNUNET_YES);
1240 if (MESH_CONNECTION_NEW == c->state)
1241 connection_change_state (c, MESH_CONNECTION_SENT);
1243 /* Remember peers */
1244 dest_peer = GMP_get (&id[size - 1]);
1245 orig_peer = GMP_get (&id[0]);
1247 /* Is it a connection to us? */
1248 if (c->own_pos == size - 1)
1250 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1251 GMP_add_path_to_origin (orig_peer, path, GNUNET_YES);
1253 add_to_peer (c, orig_peer);
1254 if (MESH_TUNNEL3_NEW == GMT_get_state (c->t))
1255 GMT_change_state (c->t, MESH_TUNNEL3_WAITING);
1257 send_connection_ack (c, GNUNET_NO);
1258 if (MESH_CONNECTION_SENT == c->state)
1259 connection_change_state (c, MESH_CONNECTION_ACK);
1261 /* Keep tunnel alive in direction dest->owner*/
1262 c->bck_maintenance_task =
1263 GNUNET_SCHEDULER_add_delayed (create_connection_time,
1264 &connection_bck_keepalive, c);
1268 /* It's for somebody else! Retransmit. */
1269 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
1270 GMP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1271 GMP_add_path_to_origin (orig_peer, path, GNUNET_NO);
1272 GMC_send_prebuilt_message (message, c, GNUNET_YES, NULL, NULL);
1279 * Core handler for path confirmations.
1281 * @param cls closure
1282 * @param message message
1283 * @param peer peer identity this notification is about
1285 * @return GNUNET_OK to keep the connection open,
1286 * GNUNET_SYSERR to close it (signal serious error)
1289 GMC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
1290 const struct GNUNET_MessageHeader *message)
1292 struct GNUNET_MESH_ConnectionACK *msg;
1293 struct MeshConnection *c;
1294 struct MeshPeerPath *p;
1295 struct MeshPeer *pi;
1296 enum MeshConnectionState oldstate;
1299 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1300 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection ACK msg\n");
1301 msg = (struct GNUNET_MESH_ConnectionACK *) message;
1302 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n",
1303 GNUNET_h2s (&msg->cid));
1304 c = connection_get (&msg->cid);
1307 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1309 LOG (GNUNET_ERROR_TYPE_DEBUG, " don't know the connection!\n");
1313 oldstate = c->state;
1314 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
1315 pi = GMP_get (peer);
1316 if (get_next_hop (c) == pi)
1318 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
1320 if (MESH_CONNECTION_SENT == oldstate)
1321 connection_change_state (c, MESH_CONNECTION_ACK);
1323 else if (get_prev_hop (c) == pi)
1325 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK\n");
1327 connection_change_state (c, MESH_CONNECTION_READY);
1331 GNUNET_break_op (0);
1335 connection_reset_timeout (c, fwd);
1337 /* Add path to peers? */
1341 GMP_add_path_to_all (p, GNUNET_YES);
1348 /* Message for us as creator? */
1349 if (GMC_is_origin (c, GNUNET_YES))
1351 if (GNUNET_NO != fwd)
1353 GNUNET_break_op (0);
1356 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
1358 /* If just created, cancel the short timeout and start a long one */
1359 if (MESH_CONNECTION_SENT == oldstate)
1360 connection_reset_timeout (c, GNUNET_YES);
1362 /* Change connection and tunnel state */
1363 connection_change_state (c, MESH_CONNECTION_READY);
1364 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1365 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1367 /* Send ACK (~TCP ACK)*/
1368 send_connection_ack (c, GNUNET_YES);
1371 /* Message for us as destination? */
1372 if (GMC_is_terminal (c, GNUNET_YES))
1374 if (GNUNET_YES != fwd)
1376 GNUNET_break_op (0);
1379 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
1381 /* If just created, cancel the short timeout and start a long one */
1382 if (MESH_CONNECTION_ACK == oldstate)
1383 connection_reset_timeout (c, GNUNET_NO);
1385 /* Change tunnel state */
1386 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1387 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1392 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1393 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1399 * Core handler for notifications of broken paths
1401 * @param cls Closure (unused).
1402 * @param id Peer identity of sending neighbor.
1403 * @param message Message.
1405 * @return GNUNET_OK to keep the connection open,
1406 * GNUNET_SYSERR to close it (signal serious error)
1409 GMC_handle_broken (void* cls,
1410 const struct GNUNET_PeerIdentity* id,
1411 const struct GNUNET_MessageHeader* message)
1413 struct GNUNET_MESH_ConnectionBroken *msg;
1414 struct MeshConnection *c;
1417 LOG (GNUNET_ERROR_TYPE_DEBUG,
1418 "Received a CONNECTION BROKEN msg from %s\n", GNUNET_i2s (id));
1419 msg = (struct GNUNET_MESH_ConnectionBroken *) message;
1420 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1421 GNUNET_i2s (&msg->peer1));
1422 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1423 GNUNET_i2s (&msg->peer2));
1424 c = connection_get (&msg->cid);
1427 GNUNET_break_op (0);
1431 fwd = is_fwd (c, id);
1432 connection_cancel_queues (c, !fwd);
1433 if (GMC_is_terminal (c, fwd))
1435 if (0 < c->pending_messages)
1436 c->destroy = GNUNET_YES;
1442 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1443 c->destroy = GNUNET_YES;
1452 * Core handler for tunnel destruction
1454 * @param cls Closure (unused).
1455 * @param peer Peer identity of sending neighbor.
1456 * @param message Message.
1458 * @return GNUNET_OK to keep the connection open,
1459 * GNUNET_SYSERR to close it (signal serious error)
1462 GMC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
1463 const struct GNUNET_MessageHeader *message)
1465 struct GNUNET_MESH_ConnectionDestroy *msg;
1466 struct MeshConnection *c;
1469 msg = (struct GNUNET_MESH_ConnectionDestroy *) message;
1470 LOG (GNUNET_ERROR_TYPE_DEBUG,
1471 "Got a CONNECTION DESTROY message from %s\n",
1473 LOG (GNUNET_ERROR_TYPE_DEBUG,
1474 " for connection %s\n",
1475 GNUNET_h2s (&msg->cid));
1476 c = connection_get (&msg->cid);
1479 /* Probably already got the message from another path,
1480 * destroyed the tunnel and retransmitted to children.
1483 GNUNET_STATISTICS_update (stats, "# control on unknown tunnel",
1487 fwd = is_fwd (c, peer);
1488 if (GNUNET_SYSERR == fwd)
1490 GNUNET_break_op (0);
1493 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1494 c->destroy = GNUNET_YES;
1500 * Generic handler for mesh network encrypted traffic.
1502 * @param peer Peer identity this notification is about.
1503 * @param msg Encrypted message.
1505 * @return GNUNET_OK to keep the connection open,
1506 * GNUNET_SYSERR to close it (signal serious error)
1509 handle_mesh_encrypted (const struct GNUNET_PeerIdentity *peer,
1510 const struct GNUNET_MESH_Encrypted *msg)
1512 struct MeshConnection *c;
1513 struct MeshPeer *neighbor;
1514 struct MeshFlowControl *fc;
1515 GNUNET_PEER_Id peer_id;
1523 size = ntohs (msg->header.size);
1525 sizeof (struct GNUNET_MESH_Encrypted) +
1526 sizeof (struct GNUNET_MessageHeader))
1528 GNUNET_break_op (0);
1531 type = ntohs (msg->header.type);
1532 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1533 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message (#%u) from %s\n",
1534 GNUNET_MESH_DEBUG_M2S (type), ntohl (msg->pid), GNUNET_i2s (peer));
1536 /* Check connection */
1537 c = connection_get (&msg->cid);
1540 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1541 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING connection unknown\n");
1545 /* Check if origin is as expected */
1546 neighbor = get_prev_hop (c);
1547 peer_id = GNUNET_PEER_search (peer);
1548 if (peer_id == GMP_get_short_id (neighbor))
1554 neighbor = get_next_hop (c);
1555 if (peer_id == GMP_get_short_id (neighbor))
1561 /* Unexpected peer sending traffic on a connection. */
1562 GNUNET_break_op (0);
1568 fc = fwd ? &c->bck_fc : &c->fwd_fc;
1569 pid = ntohl (msg->pid);
1570 if (GMC_is_pid_bigger (pid, fc->last_ack_sent))
1572 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
1573 LOG (GNUNET_ERROR_TYPE_DEBUG,
1574 "WARNING Received PID %u, (prev %u), ACK %u\n",
1575 pid, fc->last_pid_recv, fc->last_ack_sent);
1578 if (GNUNET_NO == GMC_is_pid_bigger (pid, fc->last_pid_recv))
1580 GNUNET_STATISTICS_update (stats, "# duplicate PID", 1, GNUNET_NO);
1581 LOG (GNUNET_ERROR_TYPE_DEBUG,
1582 " Pid %u not expected (%u+), dropping!\n",
1583 pid, fc->last_pid_recv + 1);
1586 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1587 connection_change_state (c, MESH_CONNECTION_READY);
1588 connection_reset_timeout (c, fwd);
1589 fc->last_pid_recv = pid;
1591 /* Is this message for us? */
1592 if (GMC_is_terminal (c, fwd))
1594 /* TODO signature verification */
1595 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1596 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1603 fc->last_pid_recv = pid;
1604 GMT_handle_encrypted (c->t, msg);
1605 GMC_send_ack (c, fwd, GNUNET_NO);
1609 /* Message not for us: forward to next hop */
1610 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1611 ttl = ntohl (msg->ttl);
1612 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
1615 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
1616 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
1617 GMC_send_ack (c, fwd, GNUNET_NO);
1621 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1622 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
1628 * Generic handler for mesh network encrypted traffic.
1630 * @param peer Peer identity this notification is about.
1631 * @param msg Encrypted message.
1633 * @return GNUNET_OK to keep the connection open,
1634 * GNUNET_SYSERR to close it (signal serious error)
1637 handle_mesh_kx (const struct GNUNET_PeerIdentity *peer,
1638 const struct GNUNET_MESH_KX *msg)
1640 struct MeshConnection *c;
1641 struct MeshPeer *neighbor;
1642 GNUNET_PEER_Id peer_id;
1648 size = ntohs (msg->header.size);
1650 sizeof (struct GNUNET_MESH_Encrypted) +
1651 sizeof (struct GNUNET_MessageHeader))
1653 GNUNET_break_op (0);
1656 type = ntohs (msg->header.type);
1657 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1658 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message from %s\n",
1659 GNUNET_MESH_DEBUG_M2S (type), GNUNET_i2s (peer));
1661 /* Check connection */
1662 c = connection_get (&msg->cid);
1665 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1666 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING connection unknown\n");
1670 /* Check if origin is as expected */
1671 neighbor = get_prev_hop (c);
1672 peer_id = GNUNET_PEER_search (peer);
1673 if (peer_id == GMP_get_short_id (neighbor))
1679 neighbor = get_next_hop (c);
1680 if (peer_id == GMP_get_short_id (neighbor))
1686 /* Unexpected peer sending traffic on a connection. */
1687 GNUNET_break_op (0);
1692 /* Count as connection confirmation. */
1693 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1694 connection_change_state (c, MESH_CONNECTION_READY);
1695 connection_reset_timeout (c, fwd);
1698 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1699 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1702 /* Is this message for us? */
1703 if (GMC_is_terminal (c, fwd))
1705 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1706 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1712 GMT_handle_kx (c->t, &msg[1].header);
1716 /* Message not for us: forward to next hop */
1717 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1718 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1719 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
1726 * Core handler for encrypted mesh network traffic (channel mgmt, data).
1728 * @param cls Closure (unused).
1729 * @param message Message received.
1730 * @param peer Peer who sent the message.
1732 * @return GNUNET_OK to keep the connection open,
1733 * GNUNET_SYSERR to close it (signal serious error)
1736 GMC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
1737 const struct GNUNET_MessageHeader *message)
1739 return handle_mesh_encrypted (peer,
1740 (struct GNUNET_MESH_Encrypted *)message);
1745 * Core handler for key exchange traffic (ephemeral key, ping, pong).
1747 * @param cls Closure (unused).
1748 * @param message Message received.
1749 * @param peer Peer who sent the message.
1751 * @return GNUNET_OK to keep the connection open,
1752 * GNUNET_SYSERR to close it (signal serious error)
1755 GMC_handle_kx (void *cls, const struct GNUNET_PeerIdentity *peer,
1756 const struct GNUNET_MessageHeader *message)
1758 return handle_mesh_kx (peer,
1759 (struct GNUNET_MESH_KX *) message);
1764 * Core handler for mesh network traffic point-to-point acks.
1766 * @param cls closure
1767 * @param message message
1768 * @param peer peer identity this notification is about
1770 * @return GNUNET_OK to keep the connection open,
1771 * GNUNET_SYSERR to close it (signal serious error)
1774 GMC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
1775 const struct GNUNET_MessageHeader *message)
1777 struct GNUNET_MESH_ACK *msg;
1778 struct MeshConnection *c;
1779 struct MeshFlowControl *fc;
1784 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1785 LOG (GNUNET_ERROR_TYPE_DEBUG, "Got an ACK packet from %s!\n",
1787 msg = (struct GNUNET_MESH_ACK *) message;
1789 c = connection_get (&msg->cid);
1793 GNUNET_STATISTICS_update (stats, "# ack on unknown connection", 1,
1798 /* Is this a forward or backward ACK? */
1799 id = GNUNET_PEER_search (peer);
1800 if (GMP_get_short_id (get_next_hop (c)) == id)
1802 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
1806 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1808 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
1814 GNUNET_break_op (0);
1818 ack = ntohl (msg->ack);
1819 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u (was %u)\n",
1820 ack, fc->last_ack_recv);
1821 if (GMC_is_pid_bigger (ack, fc->last_ack_recv))
1822 fc->last_ack_recv = ack;
1824 /* Cancel polling if the ACK is big enough. */
1825 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task &&
1826 GMC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
1828 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
1829 GNUNET_SCHEDULER_cancel (fc->poll_task);
1830 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1831 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
1834 connection_unlock_queue (c, fwd);
1841 * Core handler for mesh network traffic point-to-point ack polls.
1843 * @param cls closure
1844 * @param message message
1845 * @param peer peer identity this notification is about
1847 * @return GNUNET_OK to keep the connection open,
1848 * GNUNET_SYSERR to close it (signal serious error)
1851 GMC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
1852 const struct GNUNET_MessageHeader *message)
1854 struct GNUNET_MESH_Poll *msg;
1855 struct MeshConnection *c;
1856 struct MeshFlowControl *fc;
1861 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1862 LOG (GNUNET_ERROR_TYPE_DEBUG,
1863 "Got a POLL packet from %s!\n",
1866 msg = (struct GNUNET_MESH_Poll *) message;
1868 c = connection_get (&msg->cid);
1872 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
1874 GNUNET_break_op (0);
1878 /* Is this a forward or backward ACK?
1879 * Note: a poll should never be needed in a loopback case,
1880 * since there is no possiblility of packet loss there, so
1881 * this way of discerining FWD/BCK should not be a problem.
1883 id = GNUNET_PEER_search (peer);
1884 if (GMP_get_short_id (get_next_hop (c)) == id)
1886 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
1889 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1891 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
1896 GNUNET_break_op (0);
1900 pid = ntohl (msg->pid);
1901 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
1902 fc->last_pid_recv = pid;
1903 fwd = fc == &c->bck_fc;
1904 GMC_send_ack (c, fwd, GNUNET_YES);
1911 * Core handler for mesh keepalives.
1913 * @param cls closure
1914 * @param message message
1915 * @param peer peer identity this notification is about
1916 * @return GNUNET_OK to keep the connection open,
1917 * GNUNET_SYSERR to close it (signal serious error)
1919 * TODO: Check who we got this from, to validate route.
1922 GMC_handle_keepalive (void *cls, const struct GNUNET_PeerIdentity *peer,
1923 const struct GNUNET_MessageHeader *message)
1925 struct GNUNET_MESH_ConnectionKeepAlive *msg;
1926 struct MeshConnection *c;
1927 struct MeshPeer *neighbor;
1930 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) message;
1931 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a keepalive packet from %s\n",
1934 c = connection_get (&msg->cid);
1937 GNUNET_STATISTICS_update (stats, "# keepalive on unknown connection", 1,
1942 fwd = GNUNET_MESSAGE_TYPE_MESH_FWD_KEEPALIVE == ntohs (message->type) ?
1943 GNUNET_YES : GNUNET_NO;
1945 /* Check if origin is as expected */
1946 neighbor = get_hop (c, fwd);
1947 if (GNUNET_PEER_search (peer) != GMP_get_short_id (neighbor))
1949 GNUNET_break_op (0);
1953 connection_change_state (c, MESH_CONNECTION_READY);
1954 connection_reset_timeout (c, fwd);
1956 if (GMC_is_terminal (c, fwd))
1959 GNUNET_STATISTICS_update (stats, "# keepalives forwarded", 1, GNUNET_NO);
1960 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1967 * Send an ACK on the appropriate connection/channel, depending on
1968 * the direction and the position of the peer.
1970 * @param c Which connection to send the hop-by-hop ACK.
1971 * @param fwd Is this a fwd ACK? (will go dest->root).
1972 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
1975 GMC_send_ack (struct MeshConnection *c, int fwd, int force)
1977 unsigned int buffer;
1979 LOG (GNUNET_ERROR_TYPE_DEBUG,
1980 "GMC send %s ACK on %s\n",
1981 fwd ? "FWD" : "BCK", GMC_2s (c));
1989 /* Get available buffer space */
1990 if (GMC_is_terminal (c, fwd))
1992 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
1993 buffer = GMT_get_channels_buffer (c->t);
1997 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
1998 buffer = GMC_get_buffer (c, fwd);
2000 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2001 if (0 == buffer && GNUNET_NO == force)
2004 /* Send available buffer space */
2005 if (GMC_is_origin (c, fwd))
2007 GNUNET_assert (NULL != c->t);
2008 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2009 GMT_unchoke_channels (c->t);
2013 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2014 send_ack (c, buffer, fwd, force);
2020 * Initialize the connections subsystem
2022 * @param c Configuration handle.
2025 GMC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2027 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2029 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_MSGS_QUEUE",
2032 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2033 "MESH", "MAX_MSGS_QUEUE", "MISSING");
2034 GNUNET_SCHEDULER_shutdown ();
2039 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_CONNECTIONS",
2042 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2043 "MESH", "MAX_CONNECTIONS", "MISSING");
2044 GNUNET_SCHEDULER_shutdown ();
2049 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REFRESH_CONNECTION_TIME",
2050 &refresh_connection_time))
2052 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2053 "MESH", "REFRESH_CONNECTION_TIME", "MISSING");
2054 GNUNET_SCHEDULER_shutdown ();
2057 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2058 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_YES);
2062 * Shut down the connections subsystem.
2067 GNUNET_CONTAINER_multihashmap_destroy (connections);
2071 struct MeshConnection *
2072 GMC_new (const struct GNUNET_HashCode *cid,
2073 struct MeshTunnel3 *t,
2074 struct MeshPeerPath *p,
2075 unsigned int own_pos)
2077 struct MeshConnection *c;
2079 c = GNUNET_new (struct MeshConnection);
2081 GNUNET_CONTAINER_multihashmap_put (connections, &c->id, c,
2082 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST);
2083 fc_init (&c->fwd_fc);
2084 fc_init (&c->bck_fc);
2089 if (own_pos > p->length - 1)
2096 c->own_pos = own_pos;
2101 c->fwd_maintenance_task =
2102 GNUNET_SCHEDULER_add_delayed (create_connection_time,
2103 &connection_fwd_keepalive, c);
2105 register_neighbors (c);
2111 GMC_destroy (struct MeshConnection *c)
2116 if (2 == c->destroy) /* cancel queues -> GMP_queue_cancel -> q_destroy -> */
2117 return; /* -> message_sent -> GMC_destroy. Don't loop. */
2120 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying connection %s\n", GMC_2s (c));
2122 /* Cancel all traffic */
2123 connection_cancel_queues (c, GNUNET_YES);
2124 connection_cancel_queues (c, GNUNET_NO);
2126 /* Cancel maintainance task (keepalive/timeout) */
2127 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_maintenance_task)
2128 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2129 if (GNUNET_SCHEDULER_NO_TASK != c->bck_maintenance_task)
2130 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2132 /* Unregister from neighbors */
2133 unregister_neighbors (c);
2136 GNUNET_STATISTICS_update (stats, "# connections", -1, GNUNET_NO);
2138 GMT_remove_connection (c->t, c);
2140 if (GNUNET_NO == GMC_is_origin (c, GNUNET_YES))
2141 path_destroy (c->path);
2143 GNUNET_CONTAINER_multihashmap_remove (connections, &c->id, c);
2149 * Get the connection ID.
2151 * @param c Connection to get the ID from.
2153 * @return ID of the connection.
2155 const struct GNUNET_HashCode *
2156 GMC_get_id (const struct MeshConnection *c)
2163 * Get the connection path.
2165 * @param c Connection to get the path from.
2167 * @return path used by the connection.
2169 const struct MeshPeerPath *
2170 GMC_get_path (const struct MeshConnection *c)
2177 * Get the connection state.
2179 * @param c Connection to get the state from.
2181 * @return state of the connection.
2183 enum MeshConnectionState
2184 GMC_get_state (const struct MeshConnection *c)
2190 * Get the connection tunnel.
2192 * @param c Connection to get the tunnel from.
2194 * @return tunnel of the connection.
2196 struct MeshTunnel3 *
2197 GMC_get_tunnel (const struct MeshConnection *c)
2204 * Get free buffer space in a connection.
2206 * @param c Connection.
2207 * @param fwd Is query about FWD traffic?
2209 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2212 GMC_get_buffer (struct MeshConnection *c, int fwd)
2214 struct MeshFlowControl *fc;
2216 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2218 return (fc->queue_max - fc->queue_n);
2222 * Get how many messages have we allowed to send to us from a direction.
2224 * @param c Connection.
2225 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2227 * @return last_ack_sent - last_pid_recv
2230 GMC_get_allowed (struct MeshConnection *c, int fwd)
2232 struct MeshFlowControl *fc;
2234 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2235 if (GMC_is_pid_bigger(fc->last_pid_recv, fc->last_ack_sent))
2239 return (fc->last_ack_sent - fc->last_pid_recv);
2243 * Get messages queued in a connection.
2245 * @param c Connection.
2246 * @param fwd Is query about FWD traffic?
2248 * @return Number of messages queued.
2251 GMC_get_qn (struct MeshConnection *c, int fwd)
2253 struct MeshFlowControl *fc;
2255 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2262 * Allow the connection to advertise a buffer of the given size.
2264 * The connection will send an @c fwd ACK message (so: in direction !fwd)
2265 * allowing up to last_pid_recv + buffer.
2267 * @param c Connection.
2268 * @param buffer How many more messages the connection can accept.
2269 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
2272 GMC_allow (struct MeshConnection *c, unsigned int buffer, int fwd)
2274 send_ack (c, buffer, fwd, GNUNET_NO);
2279 * Notify other peers on a connection of a broken link. Mark connections
2280 * to destroy after all traffic has been sent.
2282 * @param c Connection on which there has been a disconnection.
2283 * @param peer Peer that disconnected.
2286 GMC_notify_broken (struct MeshConnection *c,
2287 struct MeshPeer *peer)
2291 LOG (GNUNET_ERROR_TYPE_DEBUG,
2292 " notify broken on %s due to %s disconnect\n",
2293 GMC_2s (c), GMP_2s (peer));
2295 fwd = peer == get_prev_hop (c);
2297 if (GNUNET_YES == GMC_is_terminal (c, fwd))
2299 /* Local shutdown, no one to notify about this. */
2303 if (GNUNET_NO == c->destroy)
2304 send_broken (c, &my_full_id, GMP_get_id (peer), fwd);
2306 /* Connection will have at least one pending message
2307 * (the one we just scheduled), so no point in checking whether to
2308 * destroy immediately. */
2309 c->destroy = GNUNET_YES;
2312 * Cancel all queues, if no message is left, connection will be destroyed.
2314 connection_cancel_queues (c, !fwd);
2321 * Is this peer the first one on the connection?
2323 * @param c Connection.
2324 * @param fwd Is this about fwd traffic?
2326 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
2329 GMC_is_origin (struct MeshConnection *c, int fwd)
2331 if (!fwd && c->path->length - 1 == c->own_pos )
2333 if (fwd && 0 == c->own_pos)
2340 * Is this peer the last one on the connection?
2342 * @param c Connection.
2343 * @param fwd Is this about fwd traffic?
2344 * Note that the ROOT is the terminal for BCK traffic!
2346 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
2349 GMC_is_terminal (struct MeshConnection *c, int fwd)
2351 return GMC_is_origin (c, !fwd);
2356 * See if we are allowed to send by the next hop in the given direction.
2358 * @param c Connection.
2359 * @param fwd Is this about fwd traffic?
2361 * @return #GNUNET_YES in case it's OK to send.
2364 GMC_is_sendable (struct MeshConnection *c, int fwd)
2366 struct MeshFlowControl *fc;
2368 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2369 if (GMC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2375 * Sends an already built message on a connection, properly registering
2376 * all used resources.
2378 * @param message Message to send. Function makes a copy of it.
2379 * If message is not hop-by-hop, decrements TTL of copy.
2380 * @param c Connection on which this message is transmitted.
2381 * @param fwd Is this a fwd message?
2382 * @param cont Continuation called once message is sent. Can be NULL.
2383 * @param cont_cls Closure for @c cont.
2385 * @return Handle to cancel the message before it's sent. NULL on error.
2386 * Invalid on @c cont call.
2388 struct MeshConnectionQueue *
2389 GMC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2390 struct MeshConnection *c, int fwd,
2391 GMC_sent cont, void *cont_cls)
2393 struct MeshFlowControl *fc;
2394 struct MeshConnectionQueue *q;
2400 size = ntohs (message->size);
2401 data = GNUNET_malloc (size);
2402 memcpy (data, message, size);
2403 type = ntohs (message->type);
2404 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send %s (%u bytes) on connection %s\n",
2405 GNUNET_MESH_DEBUG_M2S (type), size, GMC_2s (c));
2407 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2408 droppable = GNUNET_YES;
2411 struct GNUNET_MESH_Encrypted *emsg;
2412 struct GNUNET_MESH_KX *kmsg;
2413 struct GNUNET_MESH_ACK *amsg;
2414 struct GNUNET_MESH_Poll *pmsg;
2415 struct GNUNET_MESH_ConnectionDestroy *dmsg;
2416 struct GNUNET_MESH_ConnectionBroken *bmsg;
2419 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
2420 emsg = (struct GNUNET_MESH_Encrypted *) data;
2421 ttl = ntohl (emsg->ttl);
2424 GNUNET_break_op (0);
2429 emsg->ttl = htonl (ttl - 1);
2430 emsg->pid = htonl (fc->next_pid++);
2431 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
2433 LOG (GNUNET_ERROR_TYPE_DEBUG, "pid %u\n", ntohl (emsg->pid));
2434 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
2435 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
2436 if (GMC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
2438 GMC_start_poll (c, fwd);
2442 case GNUNET_MESSAGE_TYPE_MESH_KX:
2443 kmsg = (struct GNUNET_MESH_KX *) data;
2447 case GNUNET_MESSAGE_TYPE_MESH_ACK:
2448 amsg = (struct GNUNET_MESH_ACK *) data;
2450 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
2451 droppable = GNUNET_NO;
2454 case GNUNET_MESSAGE_TYPE_MESH_POLL:
2455 pmsg = (struct GNUNET_MESH_Poll *) data;
2457 LOG (GNUNET_ERROR_TYPE_DEBUG, " poll %u\n", ntohl (pmsg->pid));
2458 droppable = GNUNET_NO;
2461 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY:
2462 dmsg = (struct GNUNET_MESH_ConnectionDestroy *) data;
2467 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN:
2468 bmsg = (struct GNUNET_MESH_ConnectionBroken *) data;
2473 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE:
2474 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK:
2481 if (fc->queue_n > fc->queue_max && droppable)
2483 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
2486 LOG (GNUNET_ERROR_TYPE_DEBUG,
2487 "queue full: %u/%u\n",
2488 fc->queue_n, fc->queue_max);
2489 if (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED == type)
2495 return NULL; /* Drop this message */
2498 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u\n", c, c->pending_messages);
2499 c->pending_messages++;
2501 q = GNUNET_new (struct MeshConnectionQueue);
2502 q->q = GMP_queue_add (get_hop (c, fwd), data, type, size, c, fwd,
2512 q->cont_cls = cont_cls;
2518 * Cancel a previously sent message while it's in the queue.
2520 * ONLY can be called before the continuation given to the send function
2521 * is called. Once the continuation is called, the message is no longer in the
2524 * If the send function was given no continuation, GMC_cancel should
2525 * NOT be called, since it's not possible to determine if the message has
2526 * already been sent.
2528 * @param q Handle to the queue.
2531 GMC_cancel (struct MeshConnectionQueue *q)
2533 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GMC cancel message\n");
2535 /* queue destroy calls message_sent, which calls q->cont and frees q */
2536 GMP_queue_destroy (q->q, GNUNET_YES);
2541 * Sends a CREATE CONNECTION message for a path to a peer.
2542 * Changes the connection and tunnel states if necessary.
2544 * @param connection Connection to create.
2547 GMC_send_create (struct MeshConnection *connection)
2549 enum MeshTunnel3State state;
2552 size = sizeof (struct GNUNET_MESH_ConnectionCreate);
2553 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
2554 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection create\n");
2555 GMP_queue_add (get_next_hop (connection), NULL,
2556 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE,
2557 size, connection, GNUNET_YES, &message_sent, NULL);
2558 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
2559 connection, connection->pending_messages);
2560 connection->pending_messages++;
2561 state = GMT_get_state (connection->t);
2562 if (MESH_TUNNEL3_SEARCHING == state || MESH_TUNNEL3_NEW == state)
2563 GMT_change_state (connection->t, MESH_TUNNEL3_WAITING);
2564 if (MESH_CONNECTION_NEW == connection->state)
2565 connection_change_state (connection, MESH_CONNECTION_SENT);
2570 * Send a message to all peers in this connection that the connection
2571 * is no longer valid.
2573 * If some peer should not receive the message, it should be zero'ed out
2574 * before calling this function.
2576 * @param c The connection whose peers to notify.
2579 GMC_send_destroy (struct MeshConnection *c)
2581 struct GNUNET_MESH_ConnectionDestroy msg;
2583 if (GNUNET_YES == c->destroy)
2586 msg.header.size = htons (sizeof (msg));
2587 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY);;
2589 LOG (GNUNET_ERROR_TYPE_DEBUG,
2590 " sending connection destroy for connection %s\n",
2593 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_YES))
2594 GMC_send_prebuilt_message (&msg.header, c, GNUNET_YES, NULL, NULL);
2595 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_NO))
2596 GMC_send_prebuilt_message (&msg.header, c, GNUNET_NO, NULL, NULL);
2597 c->destroy = GNUNET_YES;
2602 * @brief Start a polling timer for the connection.
2604 * When a neighbor does not accept more traffic on the connection it could be
2605 * caused by a simple congestion or by a lost ACK. Polling enables to check
2606 * for the lastest ACK status for a connection.
2608 * @param c Connection.
2609 * @param fwd Should we poll in the FWD direction?
2612 GMC_start_poll (struct MeshConnection *c, int fwd)
2614 struct MeshFlowControl *fc;
2616 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2617 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task && NULL != fc->poll_msg)
2621 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
2628 * @brief Stop polling a connection for ACKs.
2630 * Once we have enough ACKs for future traffic, polls are no longer necessary.
2632 * @param c Connection.
2633 * @param fwd Should we stop the poll in the FWD direction?
2636 GMC_stop_poll (struct MeshConnection *c, int fwd)
2638 struct MeshFlowControl *fc;
2640 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2641 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
2643 GNUNET_SCHEDULER_cancel (fc->poll_task);
2644 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2649 * Get a (static) string for a connection.
2651 * @param c Connection.
2654 GMC_2s (struct MeshConnection *c)
2658 static char buf[128];
2660 sprintf (buf, "%s (->%s)", GNUNET_h2s (&c->id), GMT_2s (c->t));
2663 return GNUNET_h2s (&c->id);