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
220 * Peer queue handle, to cancel if necessary.
222 struct MeshPeerQueue *q;
225 * Continuation to call once sent.
230 * Closure for @c cont.
235 /******************************************************************************/
236 /******************************* GLOBALS ***********************************/
237 /******************************************************************************/
240 * Global handle to the statistics service.
242 extern struct GNUNET_STATISTICS_Handle *stats;
245 * Local peer own ID (memory efficient handle).
247 extern GNUNET_PEER_Id myid;
250 * Local peer own ID (full value).
252 extern struct GNUNET_PeerIdentity my_full_id;
255 * Connections known, indexed by cid (MeshConnection).
257 static struct GNUNET_CONTAINER_MultiHashMap *connections;
260 * How many connections are we willing to maintain.
261 * Local connections are always allowed, even if there are more connections than max.
263 static unsigned long long max_connections;
266 * How many messages *in total* are we willing to queue, divide by number of
267 * connections to get connection queue size.
269 static unsigned long long max_msgs_queue;
272 * How often to send path keepalives. Paths timeout after 4 missed.
274 static struct GNUNET_TIME_Relative refresh_connection_time;
277 * How often to send path create / ACKs.
279 static struct GNUNET_TIME_Relative create_connection_time;
282 /******************************************************************************/
283 /******************************** STATIC ***********************************/
284 /******************************************************************************/
286 #if 0 // avoid compiler warning for unused static function
288 fc_debug (struct MeshFlowControl *fc)
290 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
291 fc->last_pid_recv, fc->last_ack_sent);
292 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
293 fc->last_pid_sent, fc->last_ack_recv);
294 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
295 fc->queue_n, fc->queue_max);
299 connection_debug (struct MeshConnection *c)
303 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CONNECTION ***\n");
306 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
307 peer2s (c->t->peer), GMC_2s (c));
308 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
309 c->state, c->pending_messages);
310 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
311 fc_debug (&c->fwd_fc);
312 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
313 fc_debug (&c->bck_fc);
318 * Get string description for tunnel state.
320 * @param s Tunnel state.
322 * @return String representation.
325 GMC_state2s (enum MeshConnectionState s)
329 case MESH_CONNECTION_NEW:
330 return "MESH_CONNECTION_NEW";
331 case MESH_CONNECTION_SENT:
332 return "MESH_CONNECTION_SENT";
333 case MESH_CONNECTION_ACK:
334 return "MESH_CONNECTION_ACK";
335 case MESH_CONNECTION_READY:
336 return "MESH_CONNECTION_READY";
338 return "MESH_CONNECTION_STATE_ERROR";
344 * Initialize a Flow Control structure to the initial state.
346 * @param fc Flow Control structure to initialize.
349 fc_init (struct MeshFlowControl *fc)
352 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
353 fc->last_pid_recv = (uint32_t) -1;
354 fc->last_ack_sent = (uint32_t) 0;
355 fc->last_ack_recv = (uint32_t) 0;
356 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
357 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
359 fc->queue_max = (max_msgs_queue / max_connections) + 1;
366 * @param cid Connection ID.
368 static struct MeshConnection *
369 connection_get (const struct GNUNET_HashCode *cid)
371 return GNUNET_CONTAINER_multihashmap_get (connections, cid);
376 connection_change_state (struct MeshConnection* c,
377 enum MeshConnectionState state)
379 LOG (GNUNET_ERROR_TYPE_DEBUG,
380 "Connection %s state was %s\n",
381 GMC_2s (c), GMC_state2s (c->state));
382 LOG (GNUNET_ERROR_TYPE_DEBUG,
383 "Connection %s state is now %s\n",
384 GMC_2s (c), GMC_state2s (state));
390 * Callback called when a queued ACK message is sent.
392 * @param cls Closure (FC).
393 * @param c Connection this message was on.
394 * @param q Queue handler this call invalidates.
395 * @param type Type of message sent.
396 * @param fwd Was this a FWD going message?
397 * @param size Size of the message.
401 struct MeshConnection *c,
402 struct MeshConnectionQueue *q,
403 uint16_t type, int fwd, size_t size)
405 struct MeshFlowControl *fc = cls;
412 * Send an ACK on the connection, informing the predecessor about
413 * the available buffer space. Should not be called in case the peer
414 * is origin (no predecessor) in the @c fwd direction.
416 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
417 * the ACK itself goes "back" (dest->root).
419 * @param c Connection on which to send the ACK.
420 * @param buffer How much space free to advertise?
421 * @param fwd Is this FWD ACK? (Going dest -> root)
422 * @param force Don't optimize out.
425 send_ack (struct MeshConnection *c, unsigned int buffer, int fwd, int force)
427 struct MeshFlowControl *next_fc;
428 struct MeshFlowControl *prev_fc;
429 struct GNUNET_MESH_ACK msg;
433 /* If origin, there is no connection to send ACKs. Wrong function! */
434 if (GMC_is_origin (c, fwd))
440 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
441 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
443 LOG (GNUNET_ERROR_TYPE_DEBUG,
444 "connection send %s ack on %s\n",
445 fwd ? "FWD" : "BCK", GMC_2s (c));
447 /* Check if we need to transmit the ACK. */
448 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
449 if (3 < delta && buffer < delta && GNUNET_NO == force)
451 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
452 LOG (GNUNET_ERROR_TYPE_DEBUG,
453 " last pid recv: %u, last ack sent: %u\n",
454 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
458 /* Ok, ACK might be necessary, what PID to ACK? */
459 ack = prev_fc->last_pid_recv + buffer;
460 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
461 LOG (GNUNET_ERROR_TYPE_DEBUG,
462 " last pid %u, last ack %u, qmax %u, q %u\n",
463 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
464 next_fc->queue_max, next_fc->queue_n);
465 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
467 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
471 /* Check if message is already in queue */
472 if (NULL != prev_fc->ack_msg)
474 if (GMC_is_pid_bigger (ack, prev_fc->last_ack_sent))
476 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
477 GMC_cancel (prev_fc->ack_msg);
478 /* GMC_cancel triggers ack_sent(), which clears fc->ack_msg */
482 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
487 prev_fc->last_ack_sent = ack;
489 /* Build ACK message and send on connection */
490 msg.header.size = htons (sizeof (msg));
491 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ACK);
492 msg.ack = htonl (ack);
495 prev_fc->ack_msg = GMC_send_prebuilt_message (&msg.header, c, !fwd,
501 * Callback called when a queued message is sent.
503 * Calculates the average time and connection packet tracking.
505 * @param cls Closure (ConnectionQueue Handle).
506 * @param c Connection this message was on.
507 * @param type Type of message sent.
508 * @param fwd Was this a FWD going message?
509 * @param size Size of the message.
510 * @param wait Time spent waiting for core (only the time for THIS message)
513 message_sent (void *cls,
514 struct MeshConnection *c, uint16_t type,
515 int fwd, size_t size,
516 struct GNUNET_TIME_Relative wait)
518 struct MeshConnectionPerformance *p;
519 struct MeshFlowControl *fc;
520 struct MeshConnectionQueue *q = cls;
523 fc = fwd ? &c->fwd_fc : &c->bck_fc;
524 LOG (GNUNET_ERROR_TYPE_DEBUG,
527 GNUNET_MESH_DEBUG_M2S (type));
528 LOG (GNUNET_ERROR_TYPE_DEBUG, "! C_P- %p %u\n", c, c->pending_messages);
533 LOG (GNUNET_ERROR_TYPE_DEBUG, "! calling cont\n");
534 q->cont (q->cont_cls, c, q, type, fwd, size);
538 c->pending_messages--;
539 if (GNUNET_YES == c->destroy && 0 == c->pending_messages)
541 LOG (GNUNET_ERROR_TYPE_DEBUG, "! destroying connection!\n");
545 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
548 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
550 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
552 LOG (GNUNET_ERROR_TYPE_DEBUG,
553 "! accounting pid %u\n",
555 GMC_send_ack (c, fwd, GNUNET_NO);
558 case GNUNET_MESSAGE_TYPE_MESH_POLL:
562 case GNUNET_MESSAGE_TYPE_MESH_ACK:
569 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
572 return; /* Only endpoints are interested in timing. */
575 usecsperbyte = ((double) wait.rel_value_us) / size;
576 if (p->size == AVG_MSGS)
578 /* Array is full. Substract oldest value, add new one and store. */
579 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
580 p->usecsperbyte[p->idx] = usecsperbyte;
581 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
585 /* Array not yet full. Add current value to avg and store. */
586 p->usecsperbyte[p->idx] = usecsperbyte;
588 p->avg += p->usecsperbyte[p->idx];
592 p->idx = (p->idx + 1) % AVG_MSGS;
597 * Get the previous hop in a connection
599 * @param c Connection.
601 * @return Previous peer in the connection.
603 static struct MeshPeer *
604 get_prev_hop (const struct MeshConnection *c)
608 LOG (GNUNET_ERROR_TYPE_DEBUG, "Get prev hop, own pos %u\n", c->own_pos);
609 if (0 == c->own_pos || c->path->length < 2)
610 id = c->path->peers[0];
612 id = c->path->peers[c->own_pos - 1];
614 return GMP_get_short (id);
619 * Get the next hop in a connection
621 * @param c Connection.
623 * @return Next peer in the connection.
625 static struct MeshPeer *
626 get_next_hop (const struct MeshConnection *c)
630 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
631 id = c->path->peers[c->path->length - 1];
633 id = c->path->peers[c->own_pos + 1];
635 return GMP_get_short (id);
640 * Get the hop in a connection.
642 * @param c Connection.
643 * @param fwd Next hop?
645 * @return Next peer in the connection.
647 static struct MeshPeer *
648 get_hop (struct MeshConnection *c, int fwd)
651 return get_next_hop (c);
652 return get_prev_hop (c);
657 * Is traffic coming from this sender 'FWD' traffic?
659 * @param c Connection to check.
660 * @param sender Peer identity of neighbor.
662 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
663 * the traffic is 'FWD'.
664 * #GNUNET_NO for BCK.
665 * #GNUNET_SYSERR for errors.
668 is_fwd (const struct MeshConnection *c,
669 const struct GNUNET_PeerIdentity *sender)
673 id = GNUNET_PEER_search (sender);
674 if (GMP_get_short_id (get_prev_hop (c)) == id)
677 if (GMP_get_short_id (get_next_hop (c)) == id)
681 return GNUNET_SYSERR;
686 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
687 * or a first CONNECTION_ACK directed to us.
689 * @param connection Connection to confirm.
690 * @param fwd Should we send it FWD? (root->dest)
691 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
694 send_connection_ack (struct MeshConnection *connection, int fwd)
696 struct MeshTunnel3 *t;
699 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection %s ACK\n",
700 !fwd ? "FWD" : "BCK");
701 GMP_queue_add (get_hop (connection, fwd), NULL,
702 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK,
703 sizeof (struct GNUNET_MESH_ConnectionACK),
704 connection, fwd, &message_sent, NULL);
705 connection->pending_messages++;
706 if (MESH_TUNNEL3_NEW == GMT_get_state (t))
707 GMT_change_state (t, MESH_TUNNEL3_WAITING);
708 if (MESH_CONNECTION_READY != connection->state)
709 connection_change_state (connection, MESH_CONNECTION_SENT);
714 * Send a notification that a connection is broken.
716 * @param c Connection that is broken.
717 * @param id1 Peer that has disconnected.
718 * @param id2 Peer that has disconnected.
719 * @param fwd Direction towards which to send it.
722 send_broken (struct MeshConnection *c,
723 const struct GNUNET_PeerIdentity *id1,
724 const struct GNUNET_PeerIdentity *id2,
727 struct GNUNET_MESH_ConnectionBroken msg;
729 msg.header.size = htons (sizeof (struct GNUNET_MESH_ConnectionBroken));
730 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN);
734 GMC_send_prebuilt_message (&msg.header, c, fwd, NULL, NULL);
740 * Send keepalive packets for a connection.
742 * @param c Connection to keep alive..
743 * @param fwd Is this a FWD keepalive? (owner -> dest).
745 * FIXME use only one type, register in GMC_send_prebuilt_message()
748 connection_keepalive (struct MeshConnection *c, int fwd)
750 struct GNUNET_MESH_ConnectionKeepAlive *msg;
751 size_t size = sizeof (struct GNUNET_MESH_ConnectionKeepAlive);
755 type = fwd ? GNUNET_MESSAGE_TYPE_MESH_FWD_KEEPALIVE :
756 GNUNET_MESSAGE_TYPE_MESH_BCK_KEEPALIVE;
758 LOG (GNUNET_ERROR_TYPE_DEBUG,
759 "sending %s keepalive for connection %s]\n",
760 fwd ? "FWD" : "BCK", GMC_2s (c));
762 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) cbuf;
763 msg->header.size = htons (size);
764 msg->header.type = htons (type);
767 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
772 * Send CONNECTION_{CREATE/ACK} packets for a connection.
774 * @param c Connection for which to send the message.
775 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
778 connection_recreate (struct MeshConnection *c, int fwd)
780 LOG (GNUNET_ERROR_TYPE_DEBUG, "sending connection recreate\n");
784 send_connection_ack (c, GNUNET_NO);
789 * Generic connection timer management.
790 * Depending on the role of the peer in the connection will send the
791 * appropriate message (build or keepalive)
793 * @param c Conncetion to maintain.
797 connection_maintain (struct MeshConnection *c, int fwd)
799 if (MESH_TUNNEL3_SEARCHING == GMT_get_state (c->t))
801 /* TODO DHT GET with RO_BART */
806 case MESH_CONNECTION_NEW:
809 case MESH_CONNECTION_SENT:
810 connection_recreate (c, fwd);
812 case MESH_CONNECTION_READY:
813 connection_keepalive (c, fwd);
822 connection_fwd_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
824 struct MeshConnection *c = cls;
825 struct GNUNET_TIME_Relative delay;
827 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
828 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
831 connection_maintain (c, GNUNET_YES);
832 delay = c->state == MESH_CONNECTION_READY ?
833 refresh_connection_time : create_connection_time;
834 c->fwd_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
835 &connection_fwd_keepalive,
841 connection_bck_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
843 struct MeshConnection *c = cls;
844 struct GNUNET_TIME_Relative delay;
846 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
847 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
850 connection_maintain (c, GNUNET_NO);
851 delay = c->state == MESH_CONNECTION_READY ?
852 refresh_connection_time : create_connection_time;
853 c->bck_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
854 &connection_bck_keepalive,
860 * @brief Re-initiate traffic on this connection if necessary.
862 * Check if there is traffic queued towards this peer
863 * and the core transmit handle is NULL (traffic was stalled).
864 * If so, call core tmt rdy.
866 * @param c Connection on which initiate traffic.
867 * @param fwd Is this about fwd traffic?
870 connection_unlock_queue (struct MeshConnection *c, int fwd)
872 struct MeshPeer *peer;
874 LOG (GNUNET_ERROR_TYPE_DEBUG,
875 "connection_unlock_queue %s on %s\n",
876 fwd ? "FWD" : "BCK", GMC_2s (c));
878 if (GMC_is_terminal (c, fwd))
880 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal!\n");
884 peer = get_hop (c, fwd);
885 GMP_queue_unlock (peer, c);
890 * Cancel all transmissions that belong to a certain connection.
892 * If the connection is scheduled for destruction and no more messages are left,
893 * the connection will be destroyed by the continuation call.
895 * @param c Connection which to cancel. Might be destroyed during this call.
896 * @param fwd Cancel fwd traffic?
899 connection_cancel_queues (struct MeshConnection *c, int fwd)
901 struct MeshFlowControl *fc;
902 struct MeshPeer *peer;
904 LOG (GNUNET_ERROR_TYPE_DEBUG,
905 " *** Cancel %s queues for connection %s\n",
906 fwd ? "FWD" : "BCK", GMC_2s (c));
913 fc = fwd ? &c->fwd_fc : &c->bck_fc;
914 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
916 GNUNET_SCHEDULER_cancel (fc->poll_task);
917 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
918 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Cancel POLL in ccq for fc %p\n", fc);
920 peer = get_hop (c, fwd);
921 GMP_queue_cancel (peer, c);
926 * Function called if a connection has been stalled for a while,
927 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
929 * @param cls Closure (poll ctx).
930 * @param tc TaskContext.
933 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
937 * Callback called when a queued POLL message is sent.
939 * @param cls Closure (FC).
940 * @param c Connection this message was on.
941 * @param q Queue handler this call invalidates.
942 * @param type Type of message sent.
943 * @param fwd Was this a FWD going message?
944 * @param size Size of the message.
947 poll_sent (void *cls,
948 struct MeshConnection *c,
949 struct MeshConnectionQueue *q,
950 uint16_t type, int fwd, size_t size)
952 struct MeshFlowControl *fc = cls;
956 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL canceled on shutdown\n");
959 LOG (GNUNET_ERROR_TYPE_DEBUG,
960 " *** POLL sent for , scheduling new one!\n");
962 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
963 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
964 &connection_poll, fc);
965 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
970 * Function called if a connection has been stalled for a while,
971 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
973 * @param cls Closure (poll ctx).
974 * @param tc TaskContext.
977 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
979 struct MeshFlowControl *fc = cls;
980 struct GNUNET_MESH_Poll msg;
981 struct MeshConnection *c;
983 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
984 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
990 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Polling!\n");
991 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** connection [%s]\n", GMC_2s (c));
992 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** %s\n",
993 fc == &c->fwd_fc ? "FWD" : "BCK");
995 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_POLL);
996 msg.header.size = htons (sizeof (msg));
997 msg.pid = htonl (fc->last_pid_sent);
998 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** last pid sent: %u!\n", fc->last_pid_sent);
999 fc->poll_msg = GMC_send_prebuilt_message (&msg.header, c, fc == &c->fwd_fc,
1005 * Timeout function due to lack of keepalive/traffic from the owner.
1006 * Destroys connection if called.
1008 * @param cls Closure (connection to destroy).
1009 * @param tc TaskContext.
1012 connection_fwd_timeout (void *cls,
1013 const struct GNUNET_SCHEDULER_TaskContext *tc)
1015 struct MeshConnection *c = cls;
1017 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1018 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1020 LOG (GNUNET_ERROR_TYPE_DEBUG,
1021 "Connection %s[%X] FWD timed out. Destroying.\n",
1025 if (GMC_is_origin (c, GNUNET_YES)) /* If local, leave. */
1033 * Timeout function due to lack of keepalive/traffic from the destination.
1034 * Destroys connection if called.
1036 * @param cls Closure (connection to destroy).
1037 * @param tc TaskContext
1040 connection_bck_timeout (void *cls,
1041 const struct GNUNET_SCHEDULER_TaskContext *tc)
1043 struct MeshConnection *c = cls;
1045 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1046 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1049 LOG (GNUNET_ERROR_TYPE_DEBUG,
1050 "Connection %s[%X] FWD timed out. Destroying.\n",
1051 GMT_2s (c->t), c->id);
1053 if (GMC_is_origin (c, GNUNET_NO)) /* If local, leave. */
1061 * Resets the connection timeout task, some other message has done the
1063 * - For the first peer on the direction this means to send
1064 * a keepalive or a path confirmation message (either create or ACK).
1065 * - For all other peers, this means to destroy the connection,
1066 * due to lack of activity.
1067 * Starts the tiemout if no timeout was running (connection just created).
1069 * @param c Connection whose timeout to reset.
1070 * @param fwd Is this forward?
1072 * TODO use heap to improve efficiency of scheduler.
1075 connection_reset_timeout (struct MeshConnection *c, int fwd)
1077 GNUNET_SCHEDULER_TaskIdentifier *ti;
1078 GNUNET_SCHEDULER_Task f;
1080 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1082 if (GNUNET_SCHEDULER_NO_TASK != *ti)
1083 GNUNET_SCHEDULER_cancel (*ti);
1085 if (GMC_is_origin (c, fwd)) /* Startpoint */
1087 f = fwd ? &connection_fwd_keepalive : &connection_bck_keepalive;
1088 *ti = GNUNET_SCHEDULER_add_delayed (refresh_connection_time, f, c);
1090 else /* Relay, endpoint. */
1092 struct GNUNET_TIME_Relative delay;
1094 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1095 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1096 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1102 * Add the connection to the list of both neighbors.
1104 * @param c Connection.
1106 * @return #GNUNET_OK if everything went fine
1107 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1110 register_neighbors (struct MeshConnection *c)
1112 struct MeshPeer *next_peer;
1113 struct MeshPeer *prev_peer;
1115 next_peer = get_next_hop (c);
1116 prev_peer = get_prev_hop (c);
1118 if (GNUNET_NO == GMP_is_neighbor (next_peer)
1119 || GNUNET_NO == GMP_is_neighbor (prev_peer))
1120 return GNUNET_SYSERR;
1122 GMP_add_connection (next_peer, c);
1123 GMP_add_connection (prev_peer, c);
1130 * Remove the connection from the list of both neighbors.
1132 * @param c Connection.
1135 unregister_neighbors (struct MeshConnection *c)
1137 struct MeshPeer *peer;
1139 peer = get_next_hop (c);
1140 GMP_remove_connection (peer, c);
1142 peer = get_prev_hop (c);
1143 GMP_remove_connection (peer, c);
1149 * Bind the connection to the peer and the tunnel to that peer.
1151 * If the peer has no tunnel, create one. Update tunnel and connection
1152 * data structres to reflect new status.
1154 * @param c Connection.
1158 add_to_peer (struct MeshConnection *c, struct MeshPeer *peer)
1160 GMP_add_tunnel (peer);
1161 c->t = GMP_get_tunnel (peer);
1162 GMT_add_connection (c->t, c);
1165 /******************************************************************************/
1166 /******************************** API ***********************************/
1167 /******************************************************************************/
1170 * Core handler for connection creation.
1172 * @param cls Closure (unused).
1173 * @param peer Sender (neighbor).
1174 * @param message Message.
1176 * @return GNUNET_OK to keep the connection open,
1177 * GNUNET_SYSERR to close it (signal serious error)
1180 GMC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
1181 const struct GNUNET_MessageHeader *message)
1183 struct GNUNET_MESH_ConnectionCreate *msg;
1184 struct GNUNET_PeerIdentity *id;
1185 struct GNUNET_HashCode *cid;
1186 struct MeshPeerPath *path;
1187 struct MeshPeer *dest_peer;
1188 struct MeshPeer *orig_peer;
1189 struct MeshConnection *c;
1190 unsigned int own_pos;
1194 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1195 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection create msg\n");
1198 size = ntohs (message->size);
1199 if (size < sizeof (struct GNUNET_MESH_ConnectionCreate))
1201 GNUNET_break_op (0);
1205 /* Calculate hops */
1206 size -= sizeof (struct GNUNET_MESH_ConnectionCreate);
1207 if (size % sizeof (struct GNUNET_PeerIdentity))
1209 GNUNET_break_op (0);
1212 size /= sizeof (struct GNUNET_PeerIdentity);
1215 GNUNET_break_op (0);
1218 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1220 /* Get parameters */
1221 msg = (struct GNUNET_MESH_ConnectionCreate *) message;
1223 id = (struct GNUNET_PeerIdentity *) &msg[1];
1224 LOG (GNUNET_ERROR_TYPE_DEBUG,
1225 " connection %s (%s).\n",
1226 GNUNET_h2s (cid), GNUNET_i2s (id));
1228 /* Create connection */
1229 c = connection_get (cid);
1233 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating path...\n");
1234 path = path_new (size);
1236 for (i = 0; i < size; i++)
1238 LOG (GNUNET_ERROR_TYPE_DEBUG, " ... adding %s\n",
1239 GNUNET_i2s (&id[i]));
1240 path->peers[i] = GNUNET_PEER_intern (&id[i]);
1241 if (path->peers[i] == myid)
1244 if (own_pos == 0 && path->peers[own_pos] != myid)
1246 /* create path: self not found in path through self */
1247 GNUNET_break_op (0);
1248 path_destroy (path);
1251 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1252 GMP_add_path_to_all (path, GNUNET_NO);
1253 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1254 c = GMC_new (cid, NULL, path_duplicate (path), own_pos);
1257 path_destroy (path);
1260 connection_reset_timeout (c, GNUNET_YES);
1264 path = path_duplicate (c->path);
1266 if (MESH_CONNECTION_NEW == c->state)
1267 connection_change_state (c, MESH_CONNECTION_SENT);
1269 /* Remember peers */
1270 dest_peer = GMP_get (&id[size - 1]);
1271 orig_peer = GMP_get (&id[0]);
1273 /* Is it a connection to us? */
1274 if (c->own_pos == size - 1)
1276 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1277 GMP_add_path_to_origin (orig_peer, path, GNUNET_YES);
1279 add_to_peer (c, orig_peer);
1280 if (MESH_TUNNEL3_NEW == GMT_get_state (c->t))
1281 GMT_change_state (c->t, MESH_TUNNEL3_WAITING);
1283 send_connection_ack (c, GNUNET_NO);
1284 if (MESH_CONNECTION_SENT == c->state)
1285 connection_change_state (c, MESH_CONNECTION_ACK);
1287 /* Keep tunnel alive in direction dest->owner*/
1288 c->bck_maintenance_task =
1289 GNUNET_SCHEDULER_add_delayed (create_connection_time,
1290 &connection_bck_keepalive, c);
1294 /* It's for somebody else! Retransmit. */
1295 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
1296 GMP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1297 GMP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
1298 GMC_send_prebuilt_message (message, c, GNUNET_YES, NULL, NULL);
1300 path_destroy (path);
1306 * Core handler for path confirmations.
1308 * @param cls closure
1309 * @param message message
1310 * @param peer peer identity this notification is about
1312 * @return GNUNET_OK to keep the connection open,
1313 * GNUNET_SYSERR to close it (signal serious error)
1316 GMC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
1317 const struct GNUNET_MessageHeader *message)
1319 struct GNUNET_MESH_ConnectionACK *msg;
1320 struct MeshConnection *c;
1321 struct MeshPeerPath *p;
1322 struct MeshPeer *pi;
1323 enum MeshConnectionState oldstate;
1326 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1327 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection ACK msg\n");
1328 msg = (struct GNUNET_MESH_ConnectionACK *) message;
1329 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n",
1330 GNUNET_h2s (&msg->cid));
1331 c = connection_get (&msg->cid);
1334 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1336 LOG (GNUNET_ERROR_TYPE_DEBUG, " don't know the connection!\n");
1340 oldstate = c->state;
1341 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
1342 pi = GMP_get (peer);
1343 if (get_next_hop (c) == pi)
1345 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
1347 if (MESH_CONNECTION_SENT == oldstate)
1348 connection_change_state (c, MESH_CONNECTION_ACK);
1350 else if (get_prev_hop (c) == pi)
1352 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK\n");
1354 connection_change_state (c, MESH_CONNECTION_READY);
1358 GNUNET_break_op (0);
1362 connection_reset_timeout (c, fwd);
1364 /* Add path to peers? */
1368 GMP_add_path_to_all (p, GNUNET_YES);
1375 /* Message for us as creator? */
1376 if (GMC_is_origin (c, GNUNET_YES))
1378 if (GNUNET_NO != fwd)
1380 GNUNET_break_op (0);
1383 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
1385 /* If just created, cancel the short timeout and start a long one */
1386 if (MESH_CONNECTION_SENT == oldstate)
1387 connection_reset_timeout (c, GNUNET_YES);
1389 /* Change connection and tunnel state */
1390 connection_change_state (c, MESH_CONNECTION_READY);
1391 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1392 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1394 /* Send ACK (~TCP ACK)*/
1395 send_connection_ack (c, GNUNET_YES);
1399 /* Message for us as destination? */
1400 if (GMC_is_terminal (c, GNUNET_YES))
1402 if (GNUNET_YES != fwd)
1404 GNUNET_break_op (0);
1407 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
1409 /* If just created, cancel the short timeout and start a long one */
1410 if (MESH_CONNECTION_ACK == oldstate)
1411 connection_reset_timeout (c, GNUNET_NO);
1413 /* Change tunnel state */
1414 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1415 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1420 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1421 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1427 * Core handler for notifications of broken paths
1429 * @param cls Closure (unused).
1430 * @param id Peer identity of sending neighbor.
1431 * @param message Message.
1433 * @return GNUNET_OK to keep the connection open,
1434 * GNUNET_SYSERR to close it (signal serious error)
1437 GMC_handle_broken (void* cls,
1438 const struct GNUNET_PeerIdentity* id,
1439 const struct GNUNET_MessageHeader* message)
1441 struct GNUNET_MESH_ConnectionBroken *msg;
1442 struct MeshConnection *c;
1445 LOG (GNUNET_ERROR_TYPE_DEBUG,
1446 "Received a CONNECTION BROKEN msg from %s\n", GNUNET_i2s (id));
1447 msg = (struct GNUNET_MESH_ConnectionBroken *) message;
1448 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1449 GNUNET_i2s (&msg->peer1));
1450 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1451 GNUNET_i2s (&msg->peer2));
1452 c = connection_get (&msg->cid);
1455 GNUNET_break_op (0);
1459 fwd = is_fwd (c, id);
1460 connection_cancel_queues (c, !fwd);
1461 if (GMC_is_terminal (c, fwd))
1463 if (0 < c->pending_messages)
1464 c->destroy = GNUNET_YES;
1470 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1471 c->destroy = GNUNET_YES;
1480 * Core handler for tunnel destruction
1482 * @param cls Closure (unused).
1483 * @param peer Peer identity of sending neighbor.
1484 * @param message Message.
1486 * @return GNUNET_OK to keep the connection open,
1487 * GNUNET_SYSERR to close it (signal serious error)
1490 GMC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
1491 const struct GNUNET_MessageHeader *message)
1493 struct GNUNET_MESH_ConnectionDestroy *msg;
1494 struct MeshConnection *c;
1497 msg = (struct GNUNET_MESH_ConnectionDestroy *) message;
1498 LOG (GNUNET_ERROR_TYPE_DEBUG,
1499 "Got a CONNECTION DESTROY message from %s\n",
1501 LOG (GNUNET_ERROR_TYPE_DEBUG,
1502 " for connection %s\n",
1503 GNUNET_h2s (&msg->cid));
1504 c = connection_get (&msg->cid);
1507 /* Probably already got the message from another path,
1508 * destroyed the tunnel and retransmitted to children.
1511 GNUNET_STATISTICS_update (stats, "# control on unknown tunnel",
1515 fwd = is_fwd (c, peer);
1516 if (GNUNET_SYSERR == fwd)
1518 GNUNET_break_op (0);
1521 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1522 c->destroy = GNUNET_YES;
1528 * Generic handler for mesh network encrypted traffic.
1530 * @param peer Peer identity this notification is about.
1531 * @param msg Encrypted message.
1533 * @return GNUNET_OK to keep the connection open,
1534 * GNUNET_SYSERR to close it (signal serious error)
1537 handle_mesh_encrypted (const struct GNUNET_PeerIdentity *peer,
1538 const struct GNUNET_MESH_Encrypted *msg)
1540 struct MeshConnection *c;
1541 struct MeshPeer *neighbor;
1542 struct MeshFlowControl *fc;
1543 GNUNET_PEER_Id peer_id;
1551 size = ntohs (msg->header.size);
1553 sizeof (struct GNUNET_MESH_Encrypted) +
1554 sizeof (struct GNUNET_MessageHeader))
1556 GNUNET_break_op (0);
1559 type = ntohs (msg->header.type);
1560 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1561 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message (#%u) from %s\n",
1562 GNUNET_MESH_DEBUG_M2S (type), ntohl (msg->pid), GNUNET_i2s (peer));
1564 /* Check connection */
1565 c = connection_get (&msg->cid);
1568 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1569 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING connection unknown\n");
1573 /* Check if origin is as expected */
1574 neighbor = get_prev_hop (c);
1575 peer_id = GNUNET_PEER_search (peer);
1576 if (peer_id == GMP_get_short_id (neighbor))
1582 neighbor = get_next_hop (c);
1583 if (peer_id == GMP_get_short_id (neighbor))
1589 /* Unexpected peer sending traffic on a connection. */
1590 GNUNET_break_op (0);
1596 fc = fwd ? &c->bck_fc : &c->fwd_fc;
1597 pid = ntohl (msg->pid);
1598 if (GMC_is_pid_bigger (pid, fc->last_ack_sent))
1600 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
1601 LOG (GNUNET_ERROR_TYPE_DEBUG,
1602 "WARNING Received PID %u, (prev %u), ACK %u\n",
1603 pid, fc->last_pid_recv, fc->last_ack_sent);
1606 if (GNUNET_NO == GMC_is_pid_bigger (pid, fc->last_pid_recv))
1608 GNUNET_STATISTICS_update (stats, "# duplicate PID", 1, GNUNET_NO);
1609 LOG (GNUNET_ERROR_TYPE_DEBUG,
1610 " Pid %u not expected (%u+), dropping!\n",
1611 pid, fc->last_pid_recv + 1);
1614 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1615 connection_change_state (c, MESH_CONNECTION_READY);
1616 connection_reset_timeout (c, fwd);
1617 fc->last_pid_recv = pid;
1619 /* Is this message for us? */
1620 if (GMC_is_terminal (c, fwd))
1622 /* TODO signature verification */
1623 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1624 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1631 fc->last_pid_recv = pid;
1632 GMT_handle_encrypted (c->t, msg);
1633 GMC_send_ack (c, fwd, GNUNET_NO);
1637 /* Message not for us: forward to next hop */
1638 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1639 ttl = ntohl (msg->ttl);
1640 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
1643 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
1644 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
1645 GMC_send_ack (c, fwd, GNUNET_NO);
1649 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1650 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
1656 * Generic handler for mesh network encrypted traffic.
1658 * @param peer Peer identity this notification is about.
1659 * @param msg Encrypted message.
1661 * @return GNUNET_OK to keep the connection open,
1662 * GNUNET_SYSERR to close it (signal serious error)
1665 handle_mesh_kx (const struct GNUNET_PeerIdentity *peer,
1666 const struct GNUNET_MESH_KX *msg)
1668 struct MeshConnection *c;
1669 struct MeshPeer *neighbor;
1670 GNUNET_PEER_Id peer_id;
1676 size = ntohs (msg->header.size);
1678 sizeof (struct GNUNET_MESH_Encrypted) +
1679 sizeof (struct GNUNET_MessageHeader))
1681 GNUNET_break_op (0);
1684 type = ntohs (msg->header.type);
1685 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1686 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message from %s\n",
1687 GNUNET_MESH_DEBUG_M2S (type), GNUNET_i2s (peer));
1689 /* Check connection */
1690 c = connection_get (&msg->cid);
1693 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1694 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING connection unknown\n");
1698 /* Check if origin is as expected */
1699 neighbor = get_prev_hop (c);
1700 peer_id = GNUNET_PEER_search (peer);
1701 if (peer_id == GMP_get_short_id (neighbor))
1707 neighbor = get_next_hop (c);
1708 if (peer_id == GMP_get_short_id (neighbor))
1714 /* Unexpected peer sending traffic on a connection. */
1715 GNUNET_break_op (0);
1720 /* Count as connection confirmation. */
1721 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1722 connection_change_state (c, MESH_CONNECTION_READY);
1723 connection_reset_timeout (c, fwd);
1726 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1727 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1730 /* Is this message for us? */
1731 if (GMC_is_terminal (c, fwd))
1733 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1734 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1740 GMT_handle_kx (c->t, &msg[1].header);
1744 /* Message not for us: forward to next hop */
1745 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1746 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1747 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
1754 * Core handler for encrypted mesh network traffic (channel mgmt, data).
1756 * @param cls Closure (unused).
1757 * @param message Message received.
1758 * @param peer Peer who sent the message.
1760 * @return GNUNET_OK to keep the connection open,
1761 * GNUNET_SYSERR to close it (signal serious error)
1764 GMC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
1765 const struct GNUNET_MessageHeader *message)
1767 return handle_mesh_encrypted (peer,
1768 (struct GNUNET_MESH_Encrypted *)message);
1773 * Core handler for key exchange traffic (ephemeral key, ping, pong).
1775 * @param cls Closure (unused).
1776 * @param message Message received.
1777 * @param peer Peer who sent the message.
1779 * @return GNUNET_OK to keep the connection open,
1780 * GNUNET_SYSERR to close it (signal serious error)
1783 GMC_handle_kx (void *cls, const struct GNUNET_PeerIdentity *peer,
1784 const struct GNUNET_MessageHeader *message)
1786 return handle_mesh_kx (peer,
1787 (struct GNUNET_MESH_KX *) message);
1792 * Core handler for mesh network traffic point-to-point acks.
1794 * @param cls closure
1795 * @param message message
1796 * @param peer peer identity this notification is about
1798 * @return GNUNET_OK to keep the connection open,
1799 * GNUNET_SYSERR to close it (signal serious error)
1802 GMC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
1803 const struct GNUNET_MessageHeader *message)
1805 struct GNUNET_MESH_ACK *msg;
1806 struct MeshConnection *c;
1807 struct MeshFlowControl *fc;
1812 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1813 LOG (GNUNET_ERROR_TYPE_DEBUG, "Got an ACK packet from %s!\n",
1815 msg = (struct GNUNET_MESH_ACK *) message;
1817 c = connection_get (&msg->cid);
1821 GNUNET_STATISTICS_update (stats, "# ack on unknown connection", 1,
1826 /* Is this a forward or backward ACK? */
1827 id = GNUNET_PEER_search (peer);
1828 if (GMP_get_short_id (get_next_hop (c)) == id)
1830 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
1834 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1836 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
1842 GNUNET_break_op (0);
1846 ack = ntohl (msg->ack);
1847 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u (was %u)\n",
1848 ack, fc->last_ack_recv);
1849 if (GMC_is_pid_bigger (ack, fc->last_ack_recv))
1850 fc->last_ack_recv = ack;
1852 /* Cancel polling if the ACK is big enough. */
1853 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task &&
1854 GMC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
1856 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
1857 GNUNET_SCHEDULER_cancel (fc->poll_task);
1858 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1859 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
1862 connection_unlock_queue (c, fwd);
1869 * Core handler for mesh network traffic point-to-point ack polls.
1871 * @param cls closure
1872 * @param message message
1873 * @param peer peer identity this notification is about
1875 * @return GNUNET_OK to keep the connection open,
1876 * GNUNET_SYSERR to close it (signal serious error)
1879 GMC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
1880 const struct GNUNET_MessageHeader *message)
1882 struct GNUNET_MESH_Poll *msg;
1883 struct MeshConnection *c;
1884 struct MeshFlowControl *fc;
1889 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1890 LOG (GNUNET_ERROR_TYPE_DEBUG,
1891 "Got a POLL packet from %s!\n",
1894 msg = (struct GNUNET_MESH_Poll *) message;
1896 c = connection_get (&msg->cid);
1900 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
1902 GNUNET_break_op (0);
1906 /* Is this a forward or backward ACK?
1907 * Note: a poll should never be needed in a loopback case,
1908 * since there is no possiblility of packet loss there, so
1909 * this way of discerining FWD/BCK should not be a problem.
1911 id = GNUNET_PEER_search (peer);
1912 if (GMP_get_short_id (get_next_hop (c)) == id)
1914 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
1917 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1919 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
1924 GNUNET_break_op (0);
1928 pid = ntohl (msg->pid);
1929 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
1930 fc->last_pid_recv = pid;
1931 fwd = fc == &c->bck_fc;
1932 GMC_send_ack (c, fwd, GNUNET_YES);
1939 * Core handler for mesh keepalives.
1941 * @param cls closure
1942 * @param message message
1943 * @param peer peer identity this notification is about
1944 * @return GNUNET_OK to keep the connection open,
1945 * GNUNET_SYSERR to close it (signal serious error)
1947 * TODO: Check who we got this from, to validate route.
1950 GMC_handle_keepalive (void *cls, const struct GNUNET_PeerIdentity *peer,
1951 const struct GNUNET_MessageHeader *message)
1953 struct GNUNET_MESH_ConnectionKeepAlive *msg;
1954 struct MeshConnection *c;
1955 struct MeshPeer *neighbor;
1958 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) message;
1959 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a keepalive packet from %s\n",
1962 c = connection_get (&msg->cid);
1965 GNUNET_STATISTICS_update (stats, "# keepalive on unknown connection", 1,
1970 fwd = GNUNET_MESSAGE_TYPE_MESH_FWD_KEEPALIVE == ntohs (message->type) ?
1971 GNUNET_YES : GNUNET_NO;
1973 /* Check if origin is as expected */
1974 neighbor = get_hop (c, fwd);
1975 if (GNUNET_PEER_search (peer) != GMP_get_short_id (neighbor))
1977 GNUNET_break_op (0);
1981 connection_change_state (c, MESH_CONNECTION_READY);
1982 connection_reset_timeout (c, fwd);
1984 if (GMC_is_terminal (c, fwd))
1987 GNUNET_STATISTICS_update (stats, "# keepalives forwarded", 1, GNUNET_NO);
1988 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1995 * Send an ACK on the appropriate connection/channel, depending on
1996 * the direction and the position of the peer.
1998 * @param c Which connection to send the hop-by-hop ACK.
1999 * @param fwd Is this a fwd ACK? (will go dest->root).
2000 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2003 GMC_send_ack (struct MeshConnection *c, int fwd, int force)
2005 unsigned int buffer;
2007 LOG (GNUNET_ERROR_TYPE_DEBUG,
2008 "GMC send %s ACK on %s\n",
2009 fwd ? "FWD" : "BCK", GMC_2s (c));
2017 /* Get available buffer space */
2018 if (GMC_is_terminal (c, fwd))
2020 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2021 buffer = GMT_get_channels_buffer (c->t);
2025 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2026 buffer = GMC_get_buffer (c, fwd);
2028 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2029 if (0 == buffer && GNUNET_NO == force)
2032 /* Send available buffer space */
2033 if (GMC_is_origin (c, fwd))
2035 GNUNET_assert (NULL != c->t);
2036 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2037 GMT_unchoke_channels (c->t);
2041 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2042 send_ack (c, buffer, fwd, force);
2048 * Initialize the connections subsystem
2050 * @param c Configuration handle.
2053 GMC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2055 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2057 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_MSGS_QUEUE",
2060 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2061 "MESH", "MAX_MSGS_QUEUE", "MISSING");
2062 GNUNET_SCHEDULER_shutdown ();
2067 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_CONNECTIONS",
2070 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2071 "MESH", "MAX_CONNECTIONS", "MISSING");
2072 GNUNET_SCHEDULER_shutdown ();
2077 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REFRESH_CONNECTION_TIME",
2078 &refresh_connection_time))
2080 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2081 "MESH", "REFRESH_CONNECTION_TIME", "MISSING");
2082 GNUNET_SCHEDULER_shutdown ();
2085 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2086 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_YES);
2091 * Destroy each connection on shutdown.
2093 * @param cls Closure (unused).
2094 * @param key Current key code (CID, unused).
2095 * @param value Value in the hash map (connection)
2097 * @return #GNUNET_YES, because we should continue to iterate,
2100 shutdown_iterator (void *cls,
2101 const struct GNUNET_HashCode *key,
2104 struct MeshConnection *c = value;
2112 * Shut down the connections subsystem.
2117 GNUNET_CONTAINER_multihashmap_iterate (connections, &shutdown_iterator, NULL);
2118 GNUNET_CONTAINER_multihashmap_destroy (connections);
2123 struct MeshConnection *
2124 GMC_new (const struct GNUNET_HashCode *cid,
2125 struct MeshTunnel3 *t,
2126 struct MeshPeerPath *p,
2127 unsigned int own_pos)
2129 struct MeshConnection *c;
2131 c = GNUNET_new (struct MeshConnection);
2133 GNUNET_CONTAINER_multihashmap_put (connections, &c->id, c,
2134 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST);
2135 fc_init (&c->fwd_fc);
2136 fc_init (&c->bck_fc);
2141 if (own_pos > p->length - 1)
2147 c->own_pos = own_pos;
2152 c->fwd_maintenance_task =
2153 GNUNET_SCHEDULER_add_delayed (create_connection_time,
2154 &connection_fwd_keepalive, c);
2156 if (GNUNET_OK != register_neighbors (c))
2167 GMC_destroy (struct MeshConnection *c)
2172 if (2 == c->destroy) /* cancel queues -> GMP_queue_cancel -> q_destroy -> */
2173 return; /* -> message_sent -> GMC_destroy. Don't loop. */
2176 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying connection %s\n", GMC_2s (c));
2177 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc's f: %p, b: %p\n",
2178 &c->fwd_fc, &c->bck_fc);
2179 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2180 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2182 /* Cancel all traffic */
2183 connection_cancel_queues (c, GNUNET_YES);
2184 connection_cancel_queues (c, GNUNET_NO);
2186 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2187 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2189 /* Cancel maintainance task (keepalive/timeout) */
2190 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_maintenance_task)
2191 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2192 if (GNUNET_SCHEDULER_NO_TASK != c->bck_maintenance_task)
2193 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2194 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_fc.poll_task)
2196 GNUNET_SCHEDULER_cancel (c->fwd_fc.poll_task);
2197 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL FWD canceled\n");
2199 if (GNUNET_SCHEDULER_NO_TASK != c->bck_fc.poll_task)
2201 GNUNET_SCHEDULER_cancel (c->bck_fc.poll_task);
2202 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL BCK canceled\n");
2204 if (NULL != c->fwd_fc.poll_msg)
2206 GMC_cancel (c->fwd_fc.poll_msg);
2207 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg FWD canceled\n");
2209 if (NULL != c->bck_fc.poll_msg)
2211 GMC_cancel (c->bck_fc.poll_msg);
2212 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg BCK canceled\n");
2215 /* Unregister from neighbors */
2216 unregister_neighbors (c);
2219 GNUNET_STATISTICS_update (stats, "# connections", -1, GNUNET_NO);
2221 GMT_remove_connection (c->t, c);
2223 if (GNUNET_NO == GMC_is_origin (c, GNUNET_YES))
2224 path_destroy (c->path);
2226 GNUNET_break (GNUNET_YES ==
2227 GNUNET_CONTAINER_multihashmap_remove (connections, &c->id, c));
2233 * Get the connection ID.
2235 * @param c Connection to get the ID from.
2237 * @return ID of the connection.
2239 const struct GNUNET_HashCode *
2240 GMC_get_id (const struct MeshConnection *c)
2247 * Get the connection path.
2249 * @param c Connection to get the path from.
2251 * @return path used by the connection.
2253 const struct MeshPeerPath *
2254 GMC_get_path (const struct MeshConnection *c)
2261 * Get the connection state.
2263 * @param c Connection to get the state from.
2265 * @return state of the connection.
2267 enum MeshConnectionState
2268 GMC_get_state (const struct MeshConnection *c)
2274 * Get the connection tunnel.
2276 * @param c Connection to get the tunnel from.
2278 * @return tunnel of the connection.
2280 struct MeshTunnel3 *
2281 GMC_get_tunnel (const struct MeshConnection *c)
2288 * Get free buffer space in a connection.
2290 * @param c Connection.
2291 * @param fwd Is query about FWD traffic?
2293 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2296 GMC_get_buffer (struct MeshConnection *c, int fwd)
2298 struct MeshFlowControl *fc;
2300 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2302 return (fc->queue_max - fc->queue_n);
2306 * Get how many messages have we allowed to send to us from a direction.
2308 * @param c Connection.
2309 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2311 * @return last_ack_sent - last_pid_recv
2314 GMC_get_allowed (struct MeshConnection *c, int fwd)
2316 struct MeshFlowControl *fc;
2318 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2319 if (GMC_is_pid_bigger(fc->last_pid_recv, fc->last_ack_sent))
2323 return (fc->last_ack_sent - fc->last_pid_recv);
2327 * Get messages queued in a connection.
2329 * @param c Connection.
2330 * @param fwd Is query about FWD traffic?
2332 * @return Number of messages queued.
2335 GMC_get_qn (struct MeshConnection *c, int fwd)
2337 struct MeshFlowControl *fc;
2339 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2346 * Allow the connection to advertise a buffer of the given size.
2348 * The connection will send an @c fwd ACK message (so: in direction !fwd)
2349 * allowing up to last_pid_recv + buffer.
2351 * @param c Connection.
2352 * @param buffer How many more messages the connection can accept.
2353 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
2356 GMC_allow (struct MeshConnection *c, unsigned int buffer, int fwd)
2358 send_ack (c, buffer, fwd, GNUNET_NO);
2363 * Notify other peers on a connection of a broken link. Mark connections
2364 * to destroy after all traffic has been sent.
2366 * @param c Connection on which there has been a disconnection.
2367 * @param peer Peer that disconnected.
2370 GMC_notify_broken (struct MeshConnection *c,
2371 struct MeshPeer *peer)
2375 LOG (GNUNET_ERROR_TYPE_DEBUG,
2376 " notify broken on %s due to %s disconnect\n",
2377 GMC_2s (c), GMP_2s (peer));
2379 fwd = peer == get_prev_hop (c);
2381 if (GNUNET_YES == GMC_is_terminal (c, fwd))
2383 /* Local shutdown, no one to notify about this. */
2387 if (GNUNET_NO == c->destroy)
2388 send_broken (c, &my_full_id, GMP_get_id (peer), fwd);
2390 /* Connection will have at least one pending message
2391 * (the one we just scheduled), so no point in checking whether to
2392 * destroy immediately. */
2393 c->destroy = GNUNET_YES;
2396 * Cancel all queues, if no message is left, connection will be destroyed.
2398 connection_cancel_queues (c, !fwd);
2405 * Is this peer the first one on the connection?
2407 * @param c Connection.
2408 * @param fwd Is this about fwd traffic?
2410 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
2413 GMC_is_origin (struct MeshConnection *c, int fwd)
2415 if (!fwd && c->path->length - 1 == c->own_pos )
2417 if (fwd && 0 == c->own_pos)
2424 * Is this peer the last one on the connection?
2426 * @param c Connection.
2427 * @param fwd Is this about fwd traffic?
2428 * Note that the ROOT is the terminal for BCK traffic!
2430 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
2433 GMC_is_terminal (struct MeshConnection *c, int fwd)
2435 return GMC_is_origin (c, !fwd);
2440 * See if we are allowed to send by the next hop in the given direction.
2442 * @param c Connection.
2443 * @param fwd Is this about fwd traffic?
2445 * @return #GNUNET_YES in case it's OK to send.
2448 GMC_is_sendable (struct MeshConnection *c, int fwd)
2450 struct MeshFlowControl *fc;
2452 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2453 if (GMC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2459 * Sends an already built message on a connection, properly registering
2460 * all used resources.
2462 * @param message Message to send. Function makes a copy of it.
2463 * If message is not hop-by-hop, decrements TTL of copy.
2464 * @param c Connection on which this message is transmitted.
2465 * @param fwd Is this a fwd message?
2466 * @param cont Continuation called once message is sent. Can be NULL.
2467 * @param cont_cls Closure for @c cont.
2469 * @return Handle to cancel the message before it's sent.
2470 * NULL on error or if @c cont is NULL.
2471 * Invalid on @c cont call.
2473 struct MeshConnectionQueue *
2474 GMC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2475 struct MeshConnection *c, int fwd,
2476 GMC_sent cont, void *cont_cls)
2478 struct MeshFlowControl *fc;
2479 struct MeshConnectionQueue *q;
2485 size = ntohs (message->size);
2486 data = GNUNET_malloc (size);
2487 memcpy (data, message, size);
2488 type = ntohs (message->type);
2489 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send %s (%u bytes) on connection %s\n",
2490 GNUNET_MESH_DEBUG_M2S (type), size, GMC_2s (c));
2492 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2493 droppable = GNUNET_YES;
2496 struct GNUNET_MESH_Encrypted *emsg;
2497 struct GNUNET_MESH_KX *kmsg;
2498 struct GNUNET_MESH_ACK *amsg;
2499 struct GNUNET_MESH_Poll *pmsg;
2500 struct GNUNET_MESH_ConnectionDestroy *dmsg;
2501 struct GNUNET_MESH_ConnectionBroken *bmsg;
2504 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
2505 emsg = (struct GNUNET_MESH_Encrypted *) data;
2506 ttl = ntohl (emsg->ttl);
2509 GNUNET_break_op (0);
2514 emsg->ttl = htonl (ttl - 1);
2515 emsg->pid = htonl (fc->next_pid++);
2516 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
2518 LOG (GNUNET_ERROR_TYPE_DEBUG, "pid %u\n", ntohl (emsg->pid));
2519 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
2520 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
2521 if (GMC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
2523 GMC_start_poll (c, fwd);
2527 case GNUNET_MESSAGE_TYPE_MESH_KX:
2528 kmsg = (struct GNUNET_MESH_KX *) data;
2532 case GNUNET_MESSAGE_TYPE_MESH_ACK:
2533 amsg = (struct GNUNET_MESH_ACK *) data;
2535 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
2536 droppable = GNUNET_NO;
2539 case GNUNET_MESSAGE_TYPE_MESH_POLL:
2540 pmsg = (struct GNUNET_MESH_Poll *) data;
2542 LOG (GNUNET_ERROR_TYPE_DEBUG, " poll %u\n", ntohl (pmsg->pid));
2543 droppable = GNUNET_NO;
2546 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY:
2547 dmsg = (struct GNUNET_MESH_ConnectionDestroy *) data;
2552 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN:
2553 bmsg = (struct GNUNET_MESH_ConnectionBroken *) data;
2558 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE:
2559 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK:
2566 if (fc->queue_n > fc->queue_max && droppable)
2568 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
2571 LOG (GNUNET_ERROR_TYPE_DEBUG,
2572 "queue full: %u/%u\n",
2573 fc->queue_n, fc->queue_max);
2574 if (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED == type)
2580 return NULL; /* Drop this message */
2583 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u\n", c, c->pending_messages);
2584 c->pending_messages++;
2588 (void) GMP_queue_add (get_hop (c, fwd), data, type, size, c, fwd,
2589 &message_sent, NULL);
2593 q = GNUNET_new (struct MeshConnectionQueue);
2594 q->q = GMP_queue_add (get_hop (c, fwd), data, type, size, c, fwd,
2604 q->cont_cls = cont_cls;
2610 * Cancel a previously sent message while it's in the queue.
2612 * ONLY can be called before the continuation given to the send function
2613 * is called. Once the continuation is called, the message is no longer in the
2616 * @param q Handle to the queue.
2619 GMC_cancel (struct MeshConnectionQueue *q)
2621 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GMC cancel message\n");
2623 /* queue destroy calls message_sent, which calls q->cont and frees q */
2624 GMP_queue_destroy (q->q, GNUNET_YES);
2629 * Sends a CREATE CONNECTION message for a path to a peer.
2630 * Changes the connection and tunnel states if necessary.
2632 * @param connection Connection to create.
2635 GMC_send_create (struct MeshConnection *connection)
2637 enum MeshTunnel3State state;
2640 size = sizeof (struct GNUNET_MESH_ConnectionCreate);
2641 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
2642 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection create\n");
2643 GMP_queue_add (get_next_hop (connection), NULL,
2644 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE,
2645 size, connection, GNUNET_YES, &message_sent, NULL);
2646 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
2647 connection, connection->pending_messages);
2648 connection->pending_messages++;
2649 state = GMT_get_state (connection->t);
2650 if (MESH_TUNNEL3_SEARCHING == state || MESH_TUNNEL3_NEW == state)
2651 GMT_change_state (connection->t, MESH_TUNNEL3_WAITING);
2652 if (MESH_CONNECTION_NEW == connection->state)
2653 connection_change_state (connection, MESH_CONNECTION_SENT);
2658 * Send a message to all peers in this connection that the connection
2659 * is no longer valid.
2661 * If some peer should not receive the message, it should be zero'ed out
2662 * before calling this function.
2664 * @param c The connection whose peers to notify.
2667 GMC_send_destroy (struct MeshConnection *c)
2669 struct GNUNET_MESH_ConnectionDestroy msg;
2671 if (GNUNET_YES == c->destroy)
2674 msg.header.size = htons (sizeof (msg));
2675 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY);;
2677 LOG (GNUNET_ERROR_TYPE_DEBUG,
2678 " sending connection destroy for connection %s\n",
2681 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_YES))
2682 GMC_send_prebuilt_message (&msg.header, c, GNUNET_YES, NULL, NULL);
2683 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_NO))
2684 GMC_send_prebuilt_message (&msg.header, c, GNUNET_NO, NULL, NULL);
2685 c->destroy = GNUNET_YES;
2690 * @brief Start a polling timer for the connection.
2692 * When a neighbor does not accept more traffic on the connection it could be
2693 * caused by a simple congestion or by a lost ACK. Polling enables to check
2694 * for the lastest ACK status for a connection.
2696 * @param c Connection.
2697 * @param fwd Should we poll in the FWD direction?
2700 GMC_start_poll (struct MeshConnection *c, int fwd)
2702 struct MeshFlowControl *fc;
2704 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2705 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL %s requested\n",
2706 fwd ? "FWD" : "BCK");
2707 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task || NULL != fc->poll_msg)
2709 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** not needed (%u, %p)\n",
2710 fc->poll_task, fc->poll_msg);
2713 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL started on request\n");
2714 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
2721 * @brief Stop polling a connection for ACKs.
2723 * Once we have enough ACKs for future traffic, polls are no longer necessary.
2725 * @param c Connection.
2726 * @param fwd Should we stop the poll in the FWD direction?
2729 GMC_stop_poll (struct MeshConnection *c, int fwd)
2731 struct MeshFlowControl *fc;
2733 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2734 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
2736 GNUNET_SCHEDULER_cancel (fc->poll_task);
2737 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2742 * Get a (static) string for a connection.
2744 * @param c Connection.
2747 GMC_2s (struct MeshConnection *c)
2751 static char buf[128];
2753 sprintf (buf, "%s (->%s)", GNUNET_h2s (&c->id), GMT_2s (c->t));
2756 return GNUNET_h2s (&c->id);