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.
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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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. At the origin of the connection
183 * it's a pointer to the destination's path pool, otherwise just a copy.
185 struct MeshPeerPath *path;
188 * Position of the local peer in the path.
190 unsigned int own_pos;
193 * Task to keep the used paths alive at the owner,
194 * time tunnel out on all the other peers.
196 GNUNET_SCHEDULER_TaskIdentifier fwd_maintenance_task;
199 * Task to keep the used paths alive at the destination,
200 * time tunnel out on all the other peers.
202 GNUNET_SCHEDULER_TaskIdentifier bck_maintenance_task;
205 * Pending message count.
207 int pending_messages;
210 * Destroy flag: if true, destroy on last message.
216 * Handle for messages queued but not yet sent.
218 struct MeshConnectionQueue
221 * Peer queue handle, to cancel if necessary.
223 struct MeshPeerQueue *q;
226 * Was this a forced message? (Do not account for it)
231 * Continuation to call once sent.
236 * Closure for @c cont.
241 /******************************************************************************/
242 /******************************* GLOBALS ***********************************/
243 /******************************************************************************/
246 * Global handle to the statistics service.
248 extern struct GNUNET_STATISTICS_Handle *stats;
251 * Local peer own ID (memory efficient handle).
253 extern GNUNET_PEER_Id myid;
256 * Local peer own ID (full value).
258 extern struct GNUNET_PeerIdentity my_full_id;
261 * Connections known, indexed by cid (MeshConnection).
263 static struct GNUNET_CONTAINER_MultiHashMap *connections;
266 * How many connections are we willing to maintain.
267 * Local connections are always allowed, even if there are more connections than max.
269 static unsigned long long max_connections;
272 * How many messages *in total* are we willing to queue, divide by number of
273 * connections to get connection queue size.
275 static unsigned long long max_msgs_queue;
278 * How often to send path keepalives. Paths timeout after 4 missed.
280 static struct GNUNET_TIME_Relative refresh_connection_time;
283 * How often to send path create / ACKs.
285 static struct GNUNET_TIME_Relative create_connection_time;
288 /******************************************************************************/
289 /******************************** STATIC ***********************************/
290 /******************************************************************************/
292 #if 0 // avoid compiler warning for unused static function
294 fc_debug (struct MeshFlowControl *fc)
296 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
297 fc->last_pid_recv, fc->last_ack_sent);
298 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
299 fc->last_pid_sent, fc->last_ack_recv);
300 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
301 fc->queue_n, fc->queue_max);
305 connection_debug (struct MeshConnection *c)
309 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CONNECTION ***\n");
312 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
313 peer2s (c->t->peer), GMC_2s (c));
314 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
315 c->state, c->pending_messages);
316 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
317 fc_debug (&c->fwd_fc);
318 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
319 fc_debug (&c->bck_fc);
324 * Get string description for tunnel state.
326 * @param s Tunnel state.
328 * @return String representation.
331 GMC_state2s (enum MeshConnectionState s)
335 case MESH_CONNECTION_NEW:
336 return "MESH_CONNECTION_NEW";
337 case MESH_CONNECTION_SENT:
338 return "MESH_CONNECTION_SENT";
339 case MESH_CONNECTION_ACK:
340 return "MESH_CONNECTION_ACK";
341 case MESH_CONNECTION_READY:
342 return "MESH_CONNECTION_READY";
343 case MESH_CONNECTION_DESTROYED:
344 return "MESH_CONNECTION_DESTROYED";
346 return "MESH_CONNECTION_STATE_ERROR";
352 * Initialize a Flow Control structure to the initial state.
354 * @param fc Flow Control structure to initialize.
357 fc_init (struct MeshFlowControl *fc)
360 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
361 fc->last_pid_recv = (uint32_t) -1;
362 fc->last_ack_sent = (uint32_t) 0;
363 fc->last_ack_recv = (uint32_t) 0;
364 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
365 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
367 fc->queue_max = (max_msgs_queue / max_connections) + 1;
374 * @param cid Connection ID.
376 static struct MeshConnection *
377 connection_get (const struct GNUNET_HashCode *cid)
379 return GNUNET_CONTAINER_multihashmap_get (connections, cid);
384 connection_change_state (struct MeshConnection* c,
385 enum MeshConnectionState state)
387 LOG (GNUNET_ERROR_TYPE_DEBUG,
388 "Connection %s state was %s\n",
389 GMC_2s (c), GMC_state2s (c->state));
390 if (MESH_CONNECTION_DESTROYED == c->state)
392 LOG (GNUNET_ERROR_TYPE_DEBUG, "state not changing anymore\n");
395 LOG (GNUNET_ERROR_TYPE_DEBUG,
396 "Connection %s state is now %s\n",
397 GMC_2s (c), GMC_state2s (state));
403 * Callback called when a queued ACK message is sent.
405 * @param cls Closure (FC).
406 * @param c Connection this message was on.
407 * @param q Queue handler this call invalidates.
408 * @param type Type of message sent.
409 * @param fwd Was this a FWD going message?
410 * @param size Size of the message.
414 struct MeshConnection *c,
415 struct MeshConnectionQueue *q,
416 uint16_t type, int fwd, size_t size)
418 struct MeshFlowControl *fc = cls;
425 * Send an ACK on the connection, informing the predecessor about
426 * the available buffer space. Should not be called in case the peer
427 * is origin (no predecessor) in the @c fwd direction.
429 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
430 * the ACK itself goes "back" (dest->root).
432 * @param c Connection on which to send the ACK.
433 * @param buffer How much space free to advertise?
434 * @param fwd Is this FWD ACK? (Going dest -> root)
435 * @param force Don't optimize out.
438 send_ack (struct MeshConnection *c, unsigned int buffer, int fwd, int force)
440 struct MeshFlowControl *next_fc;
441 struct MeshFlowControl *prev_fc;
442 struct GNUNET_MESH_ACK msg;
446 /* If origin, there is no connection to send ACKs. Wrong function! */
447 if (GMC_is_origin (c, fwd))
453 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
454 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
456 LOG (GNUNET_ERROR_TYPE_DEBUG,
457 "connection send %s ack on %s\n",
458 GM_f2s (fwd), GMC_2s (c));
460 /* Check if we need to transmit the ACK. */
461 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
462 if (3 < delta && buffer < delta && GNUNET_NO == force)
464 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
465 LOG (GNUNET_ERROR_TYPE_DEBUG,
466 " last pid recv: %u, last ack sent: %u\n",
467 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
471 /* Ok, ACK might be necessary, what PID to ACK? */
472 ack = prev_fc->last_pid_recv + buffer;
473 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
474 LOG (GNUNET_ERROR_TYPE_DEBUG,
475 " last pid %u, last ack %u, qmax %u, q %u\n",
476 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
477 next_fc->queue_max, next_fc->queue_n);
478 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
480 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
484 /* Check if message is already in queue */
485 if (NULL != prev_fc->ack_msg)
487 if (GM_is_pid_bigger (ack, prev_fc->last_ack_sent))
489 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
490 GMC_cancel (prev_fc->ack_msg);
491 /* GMC_cancel triggers ack_sent(), which clears fc->ack_msg */
495 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
500 prev_fc->last_ack_sent = ack;
502 /* Build ACK message and send on connection */
503 msg.header.size = htons (sizeof (msg));
504 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ACK);
505 msg.ack = htonl (ack);
508 prev_fc->ack_msg = GMC_send_prebuilt_message (&msg.header, c,
515 * Callback called when a queued message is sent.
517 * Calculates the average time and connection packet tracking.
519 * @param cls Closure (ConnectionQueue Handle).
520 * @param c Connection this message was on.
521 * @param type Type of message sent.
522 * @param fwd Was this a FWD going message?
523 * @param size Size of the message.
524 * @param wait Time spent waiting for core (only the time for THIS message)
527 message_sent (void *cls,
528 struct MeshConnection *c, uint16_t type,
529 int fwd, size_t size,
530 struct GNUNET_TIME_Relative wait)
532 struct MeshConnectionPerformance *p;
533 struct MeshFlowControl *fc;
534 struct MeshConnectionQueue *q = cls;
538 fc = fwd ? &c->fwd_fc : &c->bck_fc;
539 LOG (GNUNET_ERROR_TYPE_DEBUG,
543 LOG (GNUNET_ERROR_TYPE_DEBUG, "! C_P- %p %u\n", c, c->pending_messages);
549 LOG (GNUNET_ERROR_TYPE_DEBUG, "! calling cont\n");
550 q->cont (q->cont_cls, c, q, type, fwd, size);
554 else if (type == GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED)
556 /* If NULL == q and ENCRYPTED == type, message must have been ch_mngmnt */
563 c->pending_messages--;
564 if (GNUNET_YES == c->destroy && 0 == c->pending_messages)
566 LOG (GNUNET_ERROR_TYPE_DEBUG, "! destroying connection!\n");
570 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
573 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
575 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
576 if (GNUNET_NO == forced)
579 LOG (GNUNET_ERROR_TYPE_DEBUG,
580 "! accounting pid %u\n",
585 LOG (GNUNET_ERROR_TYPE_DEBUG,
586 "! forced, Q_N not accounting pid %u\n",
589 GMC_send_ack (c, fwd, GNUNET_NO);
592 case GNUNET_MESSAGE_TYPE_MESH_POLL:
596 case GNUNET_MESSAGE_TYPE_MESH_ACK:
603 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
606 return; /* Only endpoints are interested in timing. */
609 usecsperbyte = ((double) wait.rel_value_us) / size;
610 if (p->size == AVG_MSGS)
612 /* Array is full. Substract oldest value, add new one and store. */
613 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
614 p->usecsperbyte[p->idx] = usecsperbyte;
615 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
619 /* Array not yet full. Add current value to avg and store. */
620 p->usecsperbyte[p->idx] = usecsperbyte;
622 p->avg += p->usecsperbyte[p->idx];
626 p->idx = (p->idx + 1) % AVG_MSGS;
631 * Get the previous hop in a connection
633 * @param c Connection.
635 * @return Previous peer in the connection.
637 static struct MeshPeer *
638 get_prev_hop (const struct MeshConnection *c)
642 LOG (GNUNET_ERROR_TYPE_DEBUG, "Get prev hop, own pos %u\n", c->own_pos);
643 if (0 == c->own_pos || c->path->length < 2)
644 id = c->path->peers[0];
646 id = c->path->peers[c->own_pos - 1];
648 return GMP_get_short (id);
653 * Get the next hop in a connection
655 * @param c Connection.
657 * @return Next peer in the connection.
659 static struct MeshPeer *
660 get_next_hop (const struct MeshConnection *c)
664 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
665 id = c->path->peers[c->path->length - 1];
667 id = c->path->peers[c->own_pos + 1];
669 return GMP_get_short (id);
674 * Get the hop in a connection.
676 * @param c Connection.
677 * @param fwd Next hop?
679 * @return Next peer in the connection.
681 static struct MeshPeer *
682 get_hop (struct MeshConnection *c, int fwd)
685 return get_next_hop (c);
686 return get_prev_hop (c);
691 * Is traffic coming from this sender 'FWD' traffic?
693 * @param c Connection to check.
694 * @param sender Peer identity of neighbor.
696 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
697 * the traffic is 'FWD'.
698 * #GNUNET_NO for BCK.
699 * #GNUNET_SYSERR for errors.
702 is_fwd (const struct MeshConnection *c,
703 const struct GNUNET_PeerIdentity *sender)
707 id = GNUNET_PEER_search (sender);
708 if (GMP_get_short_id (get_prev_hop (c)) == id)
711 if (GMP_get_short_id (get_next_hop (c)) == id)
715 return GNUNET_SYSERR;
720 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
721 * or a first CONNECTION_ACK directed to us.
723 * @param connection Connection to confirm.
724 * @param fwd Should we send it FWD? (root->dest)
725 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
728 send_connection_ack (struct MeshConnection *connection, int fwd)
730 struct MeshTunnel3 *t;
733 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection %s ACK\n",
735 GMP_queue_add (get_hop (connection, fwd), NULL,
736 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK,
737 sizeof (struct GNUNET_MESH_ConnectionACK),
738 connection, fwd, &message_sent, NULL);
739 connection->pending_messages++;
740 if (MESH_TUNNEL3_NEW == GMT_get_cstate (t))
741 GMT_change_cstate (t, MESH_TUNNEL3_WAITING);
742 if (MESH_CONNECTION_READY != connection->state)
743 connection_change_state (connection, MESH_CONNECTION_SENT);
748 * Send a notification that a connection is broken.
750 * @param c Connection that is broken.
751 * @param id1 Peer that has disconnected.
752 * @param id2 Peer that has disconnected.
753 * @param fwd Direction towards which to send it.
756 send_broken (struct MeshConnection *c,
757 const struct GNUNET_PeerIdentity *id1,
758 const struct GNUNET_PeerIdentity *id2,
761 struct GNUNET_MESH_ConnectionBroken msg;
763 msg.header.size = htons (sizeof (struct GNUNET_MESH_ConnectionBroken));
764 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN);
768 GMC_send_prebuilt_message (&msg.header, c, fwd, GNUNET_YES, NULL, NULL);
773 * Send keepalive packets for a connection.
775 * @param c Connection to keep alive..
776 * @param fwd Is this a FWD keepalive? (owner -> dest).
779 connection_keepalive (struct MeshConnection *c, int fwd)
781 struct GNUNET_MESH_ConnectionKeepAlive *msg;
782 size_t size = sizeof (struct GNUNET_MESH_ConnectionKeepAlive);
785 LOG (GNUNET_ERROR_TYPE_DEBUG,
786 "sending %s keepalive for connection %s]\n",
787 GM_f2s (fwd), GMC_2s (c));
789 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) cbuf;
790 msg->header.size = htons (size);
791 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KEEPALIVE);
793 msg->reserved = htonl (0);
795 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_YES, NULL, NULL);
800 * Send CONNECTION_{CREATE/ACK} packets for a connection.
802 * @param c Connection for which to send the message.
803 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
806 connection_recreate (struct MeshConnection *c, int fwd)
808 LOG (GNUNET_ERROR_TYPE_DEBUG, "sending connection recreate\n");
812 send_connection_ack (c, GNUNET_NO);
817 * Generic connection timer management.
818 * Depending on the role of the peer in the connection will send the
819 * appropriate message (build or keepalive)
821 * @param c Conncetion to maintain.
825 connection_maintain (struct MeshConnection *c, int fwd)
827 if (MESH_TUNNEL3_SEARCHING == GMT_get_cstate (c->t))
829 /* TODO DHT GET with RO_BART */
834 case MESH_CONNECTION_NEW:
837 case MESH_CONNECTION_SENT:
838 connection_recreate (c, fwd);
840 case MESH_CONNECTION_READY:
841 connection_keepalive (c, fwd);
850 connection_fwd_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
852 struct MeshConnection *c = cls;
853 struct GNUNET_TIME_Relative delay;
855 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
856 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
859 connection_maintain (c, GNUNET_YES);
860 delay = c->state == MESH_CONNECTION_READY ?
861 refresh_connection_time : create_connection_time;
862 c->fwd_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
863 &connection_fwd_keepalive,
869 connection_bck_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
871 struct MeshConnection *c = cls;
872 struct GNUNET_TIME_Relative delay;
874 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
875 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
878 connection_maintain (c, GNUNET_NO);
879 delay = c->state == MESH_CONNECTION_READY ?
880 refresh_connection_time : create_connection_time;
881 c->bck_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
882 &connection_bck_keepalive,
888 * @brief Re-initiate traffic on this connection if necessary.
890 * Check if there is traffic queued towards this peer
891 * and the core transmit handle is NULL (traffic was stalled).
892 * If so, call core tmt rdy.
894 * @param c Connection on which initiate traffic.
895 * @param fwd Is this about fwd traffic?
898 connection_unlock_queue (struct MeshConnection *c, int fwd)
900 struct MeshPeer *peer;
902 LOG (GNUNET_ERROR_TYPE_DEBUG,
903 "connection_unlock_queue %s on %s\n",
904 GM_f2s (fwd), GMC_2s (c));
906 if (GMC_is_terminal (c, fwd))
908 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal!\n");
912 peer = get_hop (c, fwd);
913 GMP_queue_unlock (peer, c);
918 * Cancel all transmissions that belong to a certain connection.
920 * If the connection is scheduled for destruction and no more messages are left,
921 * the connection will be destroyed by the continuation call.
923 * @param c Connection which to cancel. Might be destroyed during this call.
924 * @param fwd Cancel fwd traffic?
927 connection_cancel_queues (struct MeshConnection *c, int fwd)
929 struct MeshFlowControl *fc;
930 struct MeshPeer *peer;
932 LOG (GNUNET_ERROR_TYPE_DEBUG,
933 " *** Cancel %s queues for connection %s\n",
934 GM_f2s (fwd), GMC_2s (c));
941 fc = fwd ? &c->fwd_fc : &c->bck_fc;
942 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
944 GNUNET_SCHEDULER_cancel (fc->poll_task);
945 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
946 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Cancel POLL in ccq for fc %p\n", fc);
948 peer = get_hop (c, fwd);
949 GMP_queue_cancel (peer, c);
954 * Function called if a connection has been stalled for a while,
955 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
957 * @param cls Closure (poll ctx).
958 * @param tc TaskContext.
961 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
965 * Callback called when a queued POLL message is sent.
967 * @param cls Closure (FC).
968 * @param c Connection this message was on.
969 * @param q Queue handler this call invalidates.
970 * @param type Type of message sent.
971 * @param fwd Was this a FWD going message?
972 * @param size Size of the message.
975 poll_sent (void *cls,
976 struct MeshConnection *c,
977 struct MeshConnectionQueue *q,
978 uint16_t type, int fwd, size_t size)
980 struct MeshFlowControl *fc = cls;
984 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL canceled on shutdown\n");
987 LOG (GNUNET_ERROR_TYPE_DEBUG,
988 " *** POLL sent for , scheduling new one!\n");
990 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
991 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
992 &connection_poll, fc);
993 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
998 * Function called if a connection has been stalled for a while,
999 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1001 * @param cls Closure (poll ctx).
1002 * @param tc TaskContext.
1005 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1007 struct MeshFlowControl *fc = cls;
1008 struct GNUNET_MESH_Poll msg;
1009 struct MeshConnection *c;
1011 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1012 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1018 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Polling!\n");
1019 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** connection [%s]\n", GMC_2s (c));
1020 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** %s\n",
1021 fc == &c->fwd_fc ? "FWD" : "BCK");
1023 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_POLL);
1024 msg.header.size = htons (sizeof (msg));
1025 msg.pid = htonl (fc->last_pid_sent);
1026 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** last pid sent: %u!\n", fc->last_pid_sent);
1027 fc->poll_msg = GMC_send_prebuilt_message (&msg.header, c,
1028 fc == &c->fwd_fc, GNUNET_YES,
1034 * Timeout function due to lack of keepalive/traffic from the owner.
1035 * Destroys connection if called.
1037 * @param cls Closure (connection to destroy).
1038 * @param tc TaskContext.
1041 connection_fwd_timeout (void *cls,
1042 const struct GNUNET_SCHEDULER_TaskContext *tc)
1044 struct MeshConnection *c = cls;
1046 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1047 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1049 LOG (GNUNET_ERROR_TYPE_DEBUG,
1050 "Connection %s[%X] FWD timed out. Destroying.\n",
1054 if (GMC_is_origin (c, GNUNET_YES)) /* If local, leave. */
1062 * Timeout function due to lack of keepalive/traffic from the destination.
1063 * Destroys connection if called.
1065 * @param cls Closure (connection to destroy).
1066 * @param tc TaskContext
1069 connection_bck_timeout (void *cls,
1070 const struct GNUNET_SCHEDULER_TaskContext *tc)
1072 struct MeshConnection *c = cls;
1074 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1075 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1078 LOG (GNUNET_ERROR_TYPE_DEBUG,
1079 "Connection %s[%X] FWD timed out. Destroying.\n",
1080 GMT_2s (c->t), c->id);
1082 if (GMC_is_origin (c, GNUNET_NO)) /* If local, leave. */
1090 * Resets the connection timeout task, some other message has done the
1092 * - For the first peer on the direction this means to send
1093 * a keepalive or a path confirmation message (either create or ACK).
1094 * - For all other peers, this means to destroy the connection,
1095 * due to lack of activity.
1096 * Starts the timeout if no timeout was running (connection just created).
1098 * @param c Connection whose timeout to reset.
1099 * @param fwd Is this forward?
1101 * TODO use heap to improve efficiency of scheduler.
1104 connection_reset_timeout (struct MeshConnection *c, int fwd)
1106 GNUNET_SCHEDULER_TaskIdentifier *ti;
1107 GNUNET_SCHEDULER_Task f;
1109 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1111 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GM_f2s (fwd));
1113 if (GNUNET_SCHEDULER_NO_TASK != *ti)
1114 GNUNET_SCHEDULER_cancel (*ti);
1116 if (GMC_is_origin (c, fwd)) /* Startpoint */
1118 f = fwd ? &connection_fwd_keepalive : &connection_bck_keepalive;
1119 *ti = GNUNET_SCHEDULER_add_delayed (refresh_connection_time, f, c);
1121 else /* Relay, endpoint. */
1123 struct GNUNET_TIME_Relative delay;
1125 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1126 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1127 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1133 * Add the connection to the list of both neighbors.
1135 * @param c Connection.
1137 * @return #GNUNET_OK if everything went fine
1138 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1141 register_neighbors (struct MeshConnection *c)
1143 struct MeshPeer *next_peer;
1144 struct MeshPeer *prev_peer;
1146 next_peer = get_next_hop (c);
1147 prev_peer = get_prev_hop (c);
1149 if (GNUNET_NO == GMP_is_neighbor (next_peer)
1150 || GNUNET_NO == GMP_is_neighbor (prev_peer))
1152 if (GMC_is_origin (c, GNUNET_YES))
1153 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1154 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1156 LOG (GNUNET_ERROR_TYPE_DEBUG, " register neighbors failed\n");
1157 LOG (GNUNET_ERROR_TYPE_DEBUG, " prev: %s, %d\n",
1158 GMP_2s (prev_peer), GMP_is_neighbor (prev_peer));
1159 LOG (GNUNET_ERROR_TYPE_DEBUG, " next: %s, %d\n",
1160 GMP_2s (next_peer), GMP_is_neighbor (next_peer));
1161 return GNUNET_SYSERR;
1164 GMP_add_connection (next_peer, c);
1165 GMP_add_connection (prev_peer, c);
1172 * Remove the connection from the list of both neighbors.
1174 * @param c Connection.
1177 unregister_neighbors (struct MeshConnection *c)
1179 struct MeshPeer *peer;
1181 peer = get_next_hop (c);
1182 if (GNUNET_OK != GMP_remove_connection (peer, c))
1183 GNUNET_break (MESH_CONNECTION_NEW == c->state);
1185 peer = get_prev_hop (c);
1186 if (GNUNET_OK != GMP_remove_connection (peer, c))
1187 GNUNET_break (MESH_CONNECTION_NEW == c->state);
1192 * Bind the connection to the peer and the tunnel to that peer.
1194 * If the peer has no tunnel, create one. Update tunnel and connection
1195 * data structres to reflect new status.
1197 * @param c Connection.
1201 add_to_peer (struct MeshConnection *c, struct MeshPeer *peer)
1203 GMP_add_tunnel (peer);
1204 c->t = GMP_get_tunnel (peer);
1205 GMT_add_connection (c->t, c);
1208 /******************************************************************************/
1209 /******************************** API ***********************************/
1210 /******************************************************************************/
1213 * Core handler for connection creation.
1215 * @param cls Closure (unused).
1216 * @param peer Sender (neighbor).
1217 * @param message Message.
1219 * @return GNUNET_OK to keep the connection open,
1220 * GNUNET_SYSERR to close it (signal serious error)
1223 GMC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
1224 const struct GNUNET_MessageHeader *message)
1226 struct GNUNET_MESH_ConnectionCreate *msg;
1227 struct GNUNET_PeerIdentity *id;
1228 struct GNUNET_HashCode *cid;
1229 struct MeshPeerPath *path;
1230 struct MeshPeer *dest_peer;
1231 struct MeshPeer *orig_peer;
1232 struct MeshConnection *c;
1233 unsigned int own_pos;
1237 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1238 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection create msg\n");
1241 size = ntohs (message->size);
1242 if (size < sizeof (struct GNUNET_MESH_ConnectionCreate))
1244 GNUNET_break_op (0);
1248 /* Calculate hops */
1249 size -= sizeof (struct GNUNET_MESH_ConnectionCreate);
1250 if (size % sizeof (struct GNUNET_PeerIdentity))
1252 GNUNET_break_op (0);
1255 size /= sizeof (struct GNUNET_PeerIdentity);
1258 GNUNET_break_op (0);
1261 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1263 /* Get parameters */
1264 msg = (struct GNUNET_MESH_ConnectionCreate *) message;
1266 id = (struct GNUNET_PeerIdentity *) &msg[1];
1267 LOG (GNUNET_ERROR_TYPE_DEBUG,
1268 " connection %s (%s).\n",
1269 GNUNET_h2s (cid), GNUNET_i2s (id));
1271 /* Create connection */
1272 c = connection_get (cid);
1276 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating path...\n");
1277 path = path_new (size);
1279 for (i = 0; i < size; i++)
1281 LOG (GNUNET_ERROR_TYPE_DEBUG, " ... adding %s\n",
1282 GNUNET_i2s (&id[i]));
1283 path->peers[i] = GNUNET_PEER_intern (&id[i]);
1284 if (path->peers[i] == myid)
1287 if (own_pos == 0 && path->peers[own_pos] != myid)
1289 /* create path: self not found in path through self */
1290 GNUNET_break_op (0);
1291 path_destroy (path);
1294 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1295 GMP_add_path_to_all (path, GNUNET_NO);
1296 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1297 c = GMC_new (cid, NULL, path_duplicate (path), own_pos);
1300 path_destroy (path);
1303 connection_reset_timeout (c, GNUNET_YES);
1307 path = path_duplicate (c->path);
1309 if (MESH_CONNECTION_NEW == c->state)
1310 connection_change_state (c, MESH_CONNECTION_SENT);
1312 /* Remember peers */
1313 dest_peer = GMP_get (&id[size - 1]);
1314 orig_peer = GMP_get (&id[0]);
1316 /* Is it a connection to us? */
1317 if (c->own_pos == size - 1)
1319 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1320 GMP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
1322 add_to_peer (c, orig_peer);
1323 if (MESH_TUNNEL3_NEW == GMT_get_cstate (c->t))
1324 GMT_change_cstate (c->t, MESH_TUNNEL3_WAITING);
1326 send_connection_ack (c, GNUNET_NO);
1327 if (MESH_CONNECTION_SENT == c->state)
1328 connection_change_state (c, MESH_CONNECTION_ACK);
1330 /* Keep tunnel alive in direction dest->owner*/
1331 if (GNUNET_SCHEDULER_NO_TASK == c->bck_maintenance_task)
1333 c->bck_maintenance_task =
1334 GNUNET_SCHEDULER_add_delayed (create_connection_time,
1335 &connection_bck_keepalive, c);
1340 /* It's for somebody else! Retransmit. */
1341 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
1342 GMP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1343 GMP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
1344 GMC_send_prebuilt_message (message, c, GNUNET_YES, GNUNET_YES, NULL, NULL);
1346 path_destroy (path);
1352 * Core handler for path confirmations.
1354 * @param cls closure
1355 * @param message message
1356 * @param peer peer identity this notification is about
1358 * @return GNUNET_OK to keep the connection open,
1359 * GNUNET_SYSERR to close it (signal serious error)
1362 GMC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
1363 const struct GNUNET_MessageHeader *message)
1365 struct GNUNET_MESH_ConnectionACK *msg;
1366 struct MeshConnection *c;
1367 struct MeshPeerPath *p;
1368 struct MeshPeer *pi;
1369 enum MeshConnectionState oldstate;
1372 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1373 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection ACK msg\n");
1374 msg = (struct GNUNET_MESH_ConnectionACK *) message;
1375 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n",
1376 GNUNET_h2s (&msg->cid));
1377 c = connection_get (&msg->cid);
1380 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1382 LOG (GNUNET_ERROR_TYPE_DEBUG, " don't know the connection!\n");
1386 oldstate = c->state;
1387 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
1388 pi = GMP_get (peer);
1389 if (get_next_hop (c) == pi)
1391 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
1393 if (MESH_CONNECTION_SENT == oldstate)
1394 connection_change_state (c, MESH_CONNECTION_ACK);
1396 else if (get_prev_hop (c) == pi)
1398 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK\n");
1400 connection_change_state (c, MESH_CONNECTION_READY);
1404 GNUNET_break_op (0);
1408 connection_reset_timeout (c, fwd);
1410 /* Add path to peers? */
1414 GMP_add_path_to_all (p, GNUNET_YES);
1421 /* Message for us as creator? */
1422 if (GMC_is_origin (c, GNUNET_YES))
1424 if (GNUNET_NO != fwd)
1426 GNUNET_break_op (0);
1429 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
1431 /* If just created, cancel the short timeout and start a long one */
1432 if (MESH_CONNECTION_SENT == oldstate)
1433 connection_reset_timeout (c, GNUNET_YES);
1435 /* Change connection state */
1436 connection_change_state (c, MESH_CONNECTION_READY);
1437 send_connection_ack (c, GNUNET_YES);
1439 /* Change tunnel state, trigger KX */
1440 if (MESH_TUNNEL3_WAITING == GMT_get_cstate (c->t))
1441 GMT_change_cstate (c->t, MESH_TUNNEL3_READY);
1446 /* Message for us as destination? */
1447 if (GMC_is_terminal (c, GNUNET_YES))
1449 if (GNUNET_YES != fwd)
1451 GNUNET_break_op (0);
1454 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
1456 /* If just created, cancel the short timeout and start a long one */
1457 if (MESH_CONNECTION_ACK == oldstate)
1458 connection_reset_timeout (c, GNUNET_NO);
1460 /* Change tunnel state */
1461 if (MESH_TUNNEL3_WAITING == GMT_get_cstate (c->t))
1462 GMT_change_cstate (c->t, MESH_TUNNEL3_READY);
1467 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1468 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
1474 * Core handler for notifications of broken paths
1476 * @param cls Closure (unused).
1477 * @param id Peer identity of sending neighbor.
1478 * @param message Message.
1480 * @return GNUNET_OK to keep the connection open,
1481 * GNUNET_SYSERR to close it (signal serious error)
1484 GMC_handle_broken (void* cls,
1485 const struct GNUNET_PeerIdentity* id,
1486 const struct GNUNET_MessageHeader* message)
1488 struct GNUNET_MESH_ConnectionBroken *msg;
1489 struct MeshConnection *c;
1492 LOG (GNUNET_ERROR_TYPE_DEBUG,
1493 "Received a CONNECTION BROKEN msg from %s\n", GNUNET_i2s (id));
1494 msg = (struct GNUNET_MESH_ConnectionBroken *) message;
1495 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1496 GNUNET_i2s (&msg->peer1));
1497 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1498 GNUNET_i2s (&msg->peer2));
1499 c = connection_get (&msg->cid);
1502 GNUNET_break_op (0);
1506 fwd = is_fwd (c, id);
1507 if (GMC_is_terminal (c, fwd))
1509 if (0 < c->pending_messages)
1510 c->destroy = GNUNET_YES;
1516 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
1517 c->destroy = GNUNET_YES;
1518 connection_cancel_queues (c, !fwd);
1527 * Core handler for tunnel destruction
1529 * @param cls Closure (unused).
1530 * @param peer Peer identity of sending neighbor.
1531 * @param message Message.
1533 * @return GNUNET_OK to keep the connection open,
1534 * GNUNET_SYSERR to close it (signal serious error)
1537 GMC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
1538 const struct GNUNET_MessageHeader *message)
1540 struct GNUNET_MESH_ConnectionDestroy *msg;
1541 struct MeshConnection *c;
1544 msg = (struct GNUNET_MESH_ConnectionDestroy *) message;
1545 LOG (GNUNET_ERROR_TYPE_DEBUG,
1546 "Got a CONNECTION DESTROY message from %s\n",
1548 LOG (GNUNET_ERROR_TYPE_DEBUG,
1549 " for connection %s\n",
1550 GNUNET_h2s (&msg->cid));
1551 c = connection_get (&msg->cid);
1554 /* Probably already got the message from another path,
1555 * destroyed the tunnel and retransmitted to children.
1558 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1560 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection unknown: already destroyed?\n");
1563 fwd = is_fwd (c, peer);
1564 if (GNUNET_SYSERR == fwd)
1566 GNUNET_break_op (0);
1569 if (GNUNET_NO == GMC_is_terminal (c, fwd))
1570 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
1571 else if (0 == c->pending_messages)
1573 LOG (GNUNET_ERROR_TYPE_DEBUG, "! directly destroying connection!\n");
1577 c->destroy = GNUNET_YES;
1578 c->state = MESH_CONNECTION_DESTROYED;
1584 * Generic handler for mesh network encrypted traffic.
1586 * @param peer Peer identity this notification is about.
1587 * @param msg Encrypted message.
1589 * @return GNUNET_OK to keep the connection open,
1590 * GNUNET_SYSERR to close it (signal serious error)
1593 handle_mesh_encrypted (const struct GNUNET_PeerIdentity *peer,
1594 const struct GNUNET_MESH_Encrypted *msg)
1596 struct MeshConnection *c;
1597 struct MeshPeer *neighbor;
1598 struct MeshFlowControl *fc;
1599 GNUNET_PEER_Id peer_id;
1607 size = ntohs (msg->header.size);
1609 sizeof (struct GNUNET_MESH_Encrypted) +
1610 sizeof (struct GNUNET_MessageHeader))
1612 GNUNET_break_op (0);
1615 type = ntohs (msg->header.type);
1616 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1617 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message (#%u) from %s\n",
1618 GM_m2s (type), ntohl (msg->pid), GNUNET_i2s (peer));
1620 /* Check connection */
1621 c = connection_get (&msg->cid);
1624 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1625 LOG (GNUNET_ERROR_TYPE_DEBUG,
1626 "WARNING connection %s unknown\n",
1627 GNUNET_h2s (&msg->cid));
1631 /* Check if origin is as expected */
1632 neighbor = get_prev_hop (c);
1633 peer_id = GNUNET_PEER_search (peer);
1634 if (peer_id == GMP_get_short_id (neighbor))
1640 neighbor = get_next_hop (c);
1641 if (peer_id == GMP_get_short_id (neighbor))
1647 /* Unexpected peer sending traffic on a connection. */
1648 GNUNET_break_op (0);
1654 fc = fwd ? &c->bck_fc : &c->fwd_fc;
1655 pid = ntohl (msg->pid);
1656 if (GM_is_pid_bigger (pid, fc->last_ack_sent))
1658 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
1659 LOG (GNUNET_ERROR_TYPE_DEBUG,
1660 "WARNING Received PID %u, (prev %u), ACK %u\n",
1661 pid, fc->last_pid_recv, fc->last_ack_sent);
1664 if (GNUNET_NO == GM_is_pid_bigger (pid, fc->last_pid_recv))
1666 GNUNET_STATISTICS_update (stats, "# duplicate PID", 1, GNUNET_NO);
1667 LOG (GNUNET_ERROR_TYPE_DEBUG,
1668 " Pid %u not expected (%u+), dropping!\n",
1669 pid, fc->last_pid_recv + 1);
1672 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1673 connection_change_state (c, MESH_CONNECTION_READY);
1674 connection_reset_timeout (c, fwd);
1675 fc->last_pid_recv = pid;
1677 /* Is this message for us? */
1678 if (GMC_is_terminal (c, fwd))
1680 /* TODO signature verification */
1681 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1682 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1689 fc->last_pid_recv = pid;
1690 GMT_handle_encrypted (c->t, msg);
1691 GMC_send_ack (c, fwd, GNUNET_NO);
1695 /* Message not for us: forward to next hop */
1696 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1697 ttl = ntohl (msg->ttl);
1698 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
1701 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
1702 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
1703 GMC_send_ack (c, fwd, GNUNET_NO);
1707 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1708 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_NO, NULL, NULL);
1714 * Generic handler for mesh network encrypted traffic.
1716 * @param peer Peer identity this notification is about.
1717 * @param msg Encrypted message.
1719 * @return GNUNET_OK to keep the connection open,
1720 * GNUNET_SYSERR to close it (signal serious error)
1723 handle_mesh_kx (const struct GNUNET_PeerIdentity *peer,
1724 const struct GNUNET_MESH_KX *msg)
1726 struct MeshConnection *c;
1727 struct MeshPeer *neighbor;
1728 GNUNET_PEER_Id peer_id;
1734 size = ntohs (msg->header.size);
1736 sizeof (struct GNUNET_MESH_Encrypted) +
1737 sizeof (struct GNUNET_MessageHeader))
1739 GNUNET_break_op (0);
1742 type = ntohs (msg->header.type);
1743 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1744 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message from %s\n",
1745 GM_m2s (type), GNUNET_i2s (peer));
1747 /* Check connection */
1748 c = connection_get (&msg->cid);
1751 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1752 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING connection unknown\n");
1756 /* Check if origin is as expected */
1757 neighbor = get_prev_hop (c);
1758 peer_id = GNUNET_PEER_search (peer);
1759 if (peer_id == GMP_get_short_id (neighbor))
1765 neighbor = get_next_hop (c);
1766 if (peer_id == GMP_get_short_id (neighbor))
1772 /* Unexpected peer sending traffic on a connection. */
1773 GNUNET_break_op (0);
1778 /* Count as connection confirmation. */
1779 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1780 connection_change_state (c, MESH_CONNECTION_READY);
1781 connection_reset_timeout (c, fwd);
1784 if (MESH_TUNNEL3_WAITING == GMT_get_cstate (c->t))
1785 GMT_change_cstate (c->t, MESH_TUNNEL3_READY);
1788 /* Is this message for us? */
1789 if (GMC_is_terminal (c, fwd))
1791 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1792 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1798 GMT_handle_kx (c->t, &msg[1].header);
1802 /* Message not for us: forward to next hop */
1803 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1804 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1805 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_NO, NULL, NULL);
1812 * Core handler for encrypted mesh network traffic (channel mgmt, data).
1814 * @param cls Closure (unused).
1815 * @param message Message received.
1816 * @param peer Peer who sent the message.
1818 * @return GNUNET_OK to keep the connection open,
1819 * GNUNET_SYSERR to close it (signal serious error)
1822 GMC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
1823 const struct GNUNET_MessageHeader *message)
1825 return handle_mesh_encrypted (peer,
1826 (struct GNUNET_MESH_Encrypted *)message);
1831 * Core handler for key exchange traffic (ephemeral key, ping, pong).
1833 * @param cls Closure (unused).
1834 * @param message Message received.
1835 * @param peer Peer who sent the message.
1837 * @return GNUNET_OK to keep the connection open,
1838 * GNUNET_SYSERR to close it (signal serious error)
1841 GMC_handle_kx (void *cls, const struct GNUNET_PeerIdentity *peer,
1842 const struct GNUNET_MessageHeader *message)
1844 return handle_mesh_kx (peer,
1845 (struct GNUNET_MESH_KX *) message);
1850 * Core handler for mesh network traffic point-to-point acks.
1852 * @param cls closure
1853 * @param message message
1854 * @param peer peer identity this notification is about
1856 * @return GNUNET_OK to keep the connection open,
1857 * GNUNET_SYSERR to close it (signal serious error)
1860 GMC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
1861 const struct GNUNET_MessageHeader *message)
1863 struct GNUNET_MESH_ACK *msg;
1864 struct MeshConnection *c;
1865 struct MeshFlowControl *fc;
1870 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1871 LOG (GNUNET_ERROR_TYPE_DEBUG, "Got an ACK packet from %s!\n",
1873 msg = (struct GNUNET_MESH_ACK *) message;
1875 c = connection_get (&msg->cid);
1879 GNUNET_STATISTICS_update (stats, "# ack on unknown connection", 1,
1884 /* Is this a forward or backward ACK? */
1885 id = GNUNET_PEER_search (peer);
1886 if (GMP_get_short_id (get_next_hop (c)) == id)
1888 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
1892 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1894 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
1900 GNUNET_break_op (0);
1904 ack = ntohl (msg->ack);
1905 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u (was %u)\n",
1906 ack, fc->last_ack_recv);
1907 if (GM_is_pid_bigger (ack, fc->last_ack_recv))
1908 fc->last_ack_recv = ack;
1910 /* Cancel polling if the ACK is big enough. */
1911 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task &&
1912 GM_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
1914 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
1915 GNUNET_SCHEDULER_cancel (fc->poll_task);
1916 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1917 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
1920 connection_unlock_queue (c, fwd);
1927 * Core handler for mesh network traffic point-to-point ack polls.
1929 * @param cls closure
1930 * @param message message
1931 * @param peer peer identity this notification is about
1933 * @return GNUNET_OK to keep the connection open,
1934 * GNUNET_SYSERR to close it (signal serious error)
1937 GMC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
1938 const struct GNUNET_MessageHeader *message)
1940 struct GNUNET_MESH_Poll *msg;
1941 struct MeshConnection *c;
1942 struct MeshFlowControl *fc;
1947 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1948 LOG (GNUNET_ERROR_TYPE_DEBUG,
1949 "Got a POLL packet from %s!\n",
1952 msg = (struct GNUNET_MESH_Poll *) message;
1954 c = connection_get (&msg->cid);
1958 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
1960 GNUNET_break_op (0);
1964 /* Is this a forward or backward ACK?
1965 * Note: a poll should never be needed in a loopback case,
1966 * since there is no possiblility of packet loss there, so
1967 * this way of discerining FWD/BCK should not be a problem.
1969 id = GNUNET_PEER_search (peer);
1970 if (GMP_get_short_id (get_next_hop (c)) == id)
1972 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
1975 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1977 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
1982 GNUNET_break_op (0);
1986 pid = ntohl (msg->pid);
1987 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
1988 fc->last_pid_recv = pid;
1989 fwd = fc == &c->bck_fc;
1990 GMC_send_ack (c, fwd, GNUNET_YES);
1997 * Core handler for mesh keepalives.
1999 * @param cls closure
2000 * @param message message
2001 * @param peer peer identity this notification is about
2002 * @return GNUNET_OK to keep the connection open,
2003 * GNUNET_SYSERR to close it (signal serious error)
2005 * TODO: Check who we got this from, to validate route.
2008 GMC_handle_keepalive (void *cls, const struct GNUNET_PeerIdentity *peer,
2009 const struct GNUNET_MessageHeader *message)
2011 struct GNUNET_MESH_ConnectionKeepAlive *msg;
2012 struct MeshConnection *c;
2013 struct MeshPeer *neighbor;
2014 GNUNET_PEER_Id peer_id;
2017 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) message;
2018 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a keepalive packet from %s\n",
2021 c = connection_get (&msg->cid);
2024 GNUNET_STATISTICS_update (stats, "# keepalive on unknown connection", 1,
2029 /* Check if origin is as expected TODO refactor and reuse */
2030 peer_id = GNUNET_PEER_search (peer);
2031 neighbor = get_prev_hop (c);
2032 if (peer_id == GMP_get_short_id (neighbor))
2038 neighbor = get_next_hop (c);
2039 if (peer_id == GMP_get_short_id (neighbor))
2045 GNUNET_break_op (0);
2050 connection_change_state (c, MESH_CONNECTION_READY);
2051 connection_reset_timeout (c, fwd);
2053 if (GMC_is_terminal (c, fwd))
2056 GNUNET_STATISTICS_update (stats, "# keepalives forwarded", 1, GNUNET_NO);
2057 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
2064 * Send an ACK on the appropriate connection/channel, depending on
2065 * the direction and the position of the peer.
2067 * @param c Which connection to send the hop-by-hop ACK.
2068 * @param fwd Is this a fwd ACK? (will go dest->root).
2069 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2072 GMC_send_ack (struct MeshConnection *c, int fwd, int force)
2074 unsigned int buffer;
2076 LOG (GNUNET_ERROR_TYPE_DEBUG,
2077 "GMC send %s ACK on %s\n",
2078 GM_f2s (fwd), GMC_2s (c));
2086 if (GNUNET_NO != c->destroy)
2088 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2092 /* Get available buffer space */
2093 if (GMC_is_terminal (c, fwd))
2095 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2096 buffer = GMT_get_channels_buffer (c->t);
2100 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2101 buffer = GMC_get_buffer (c, fwd);
2103 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2104 if (0 == buffer && GNUNET_NO == force)
2107 /* Send available buffer space */
2108 if (GMC_is_origin (c, fwd))
2110 GNUNET_assert (NULL != c->t);
2111 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2112 GMT_unchoke_channels (c->t);
2116 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2117 send_ack (c, buffer, fwd, force);
2123 * Initialize the connections subsystem
2125 * @param c Configuration handle.
2128 GMC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2130 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2132 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_MSGS_QUEUE",
2135 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2136 "MESH", "MAX_MSGS_QUEUE", "MISSING");
2137 GNUNET_SCHEDULER_shutdown ();
2142 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_CONNECTIONS",
2145 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2146 "MESH", "MAX_CONNECTIONS", "MISSING");
2147 GNUNET_SCHEDULER_shutdown ();
2152 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REFRESH_CONNECTION_TIME",
2153 &refresh_connection_time))
2155 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2156 "MESH", "REFRESH_CONNECTION_TIME", "MISSING");
2157 GNUNET_SCHEDULER_shutdown ();
2160 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2161 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_YES);
2166 * Destroy each connection on shutdown.
2168 * @param cls Closure (unused).
2169 * @param key Current key code (CID, unused).
2170 * @param value Value in the hash map (connection)
2172 * @return #GNUNET_YES, because we should continue to iterate,
2175 shutdown_iterator (void *cls,
2176 const struct GNUNET_HashCode *key,
2179 struct MeshConnection *c = value;
2187 * Shut down the connections subsystem.
2192 GNUNET_CONTAINER_multihashmap_iterate (connections, &shutdown_iterator, NULL);
2193 GNUNET_CONTAINER_multihashmap_destroy (connections);
2198 struct MeshConnection *
2199 GMC_new (const struct GNUNET_HashCode *cid,
2200 struct MeshTunnel3 *t,
2201 struct MeshPeerPath *p,
2202 unsigned int own_pos)
2204 struct MeshConnection *c;
2206 c = GNUNET_new (struct MeshConnection);
2208 GNUNET_assert (GNUNET_OK ==
2209 GNUNET_CONTAINER_multihashmap_put (connections,
2211 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2212 fc_init (&c->fwd_fc);
2213 fc_init (&c->bck_fc);
2218 GNUNET_assert (own_pos <= p->length - 1);
2219 c->own_pos = own_pos;
2222 if (GNUNET_OK != register_neighbors (c))
2226 GMT_remove_path (c->t, p);
2236 c->fwd_maintenance_task =
2237 GNUNET_SCHEDULER_add_delayed (create_connection_time,
2238 &connection_fwd_keepalive, c);
2246 GMC_destroy (struct MeshConnection *c)
2254 if (2 == c->destroy) /* cancel queues -> GMP_queue_cancel -> q_destroy -> */
2255 return; /* -> message_sent -> GMC_destroy. Don't loop. */
2258 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying connection %s\n", GMC_2s (c));
2259 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc's f: %p, b: %p\n",
2260 &c->fwd_fc, &c->bck_fc);
2261 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2262 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2264 /* Cancel all traffic */
2265 if (NULL != c->path)
2267 connection_cancel_queues (c, GNUNET_YES);
2268 connection_cancel_queues (c, GNUNET_NO);
2269 unregister_neighbors (c);
2272 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2273 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2275 /* Cancel maintainance task (keepalive/timeout) */
2276 if (NULL != c->fwd_fc.poll_msg)
2278 GMC_cancel (c->fwd_fc.poll_msg);
2279 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg FWD canceled\n");
2281 if (NULL != c->bck_fc.poll_msg)
2283 GMC_cancel (c->bck_fc.poll_msg);
2284 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg BCK canceled\n");
2287 /* Delete from tunnel */
2289 GMT_remove_connection (c->t, c);
2291 if (GNUNET_NO == GMC_is_origin (c, GNUNET_YES) && NULL != c->path)
2292 path_destroy (c->path);
2293 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_maintenance_task)
2294 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2295 if (GNUNET_SCHEDULER_NO_TASK != c->bck_maintenance_task)
2296 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2297 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_fc.poll_task)
2299 GNUNET_SCHEDULER_cancel (c->fwd_fc.poll_task);
2300 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL FWD canceled\n");
2302 if (GNUNET_SCHEDULER_NO_TASK != c->bck_fc.poll_task)
2304 GNUNET_SCHEDULER_cancel (c->bck_fc.poll_task);
2305 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL BCK canceled\n");
2308 GNUNET_break (GNUNET_YES ==
2309 GNUNET_CONTAINER_multihashmap_remove (connections, &c->id, c));
2311 GNUNET_STATISTICS_update (stats, "# connections", -1, GNUNET_NO);
2316 * Get the connection ID.
2318 * @param c Connection to get the ID from.
2320 * @return ID of the connection.
2322 const struct GNUNET_HashCode *
2323 GMC_get_id (const struct MeshConnection *c)
2330 * Get the connection path.
2332 * @param c Connection to get the path from.
2334 * @return path used by the connection.
2336 const struct MeshPeerPath *
2337 GMC_get_path (const struct MeshConnection *c)
2339 if (GNUNET_NO == c->destroy)
2346 * Get the connection state.
2348 * @param c Connection to get the state from.
2350 * @return state of the connection.
2352 enum MeshConnectionState
2353 GMC_get_state (const struct MeshConnection *c)
2359 * Get the connection tunnel.
2361 * @param c Connection to get the tunnel from.
2363 * @return tunnel of the connection.
2365 struct MeshTunnel3 *
2366 GMC_get_tunnel (const struct MeshConnection *c)
2373 * Get free buffer space in a connection.
2375 * @param c Connection.
2376 * @param fwd Is query about FWD traffic?
2378 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2381 GMC_get_buffer (struct MeshConnection *c, int fwd)
2383 struct MeshFlowControl *fc;
2385 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2387 return (fc->queue_max - fc->queue_n);
2391 * Get how many messages have we allowed to send to us from a direction.
2393 * @param c Connection.
2394 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2396 * @return last_ack_sent - last_pid_recv
2399 GMC_get_allowed (struct MeshConnection *c, int fwd)
2401 struct MeshFlowControl *fc;
2403 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2404 if (GM_is_pid_bigger(fc->last_pid_recv, fc->last_ack_sent))
2408 return (fc->last_ack_sent - fc->last_pid_recv);
2412 * Get messages queued in a connection.
2414 * @param c Connection.
2415 * @param fwd Is query about FWD traffic?
2417 * @return Number of messages queued.
2420 GMC_get_qn (struct MeshConnection *c, int fwd)
2422 struct MeshFlowControl *fc;
2424 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2431 * Allow the connection to advertise a buffer of the given size.
2433 * The connection will send an @c fwd ACK message (so: in direction !fwd)
2434 * allowing up to last_pid_recv + buffer.
2436 * @param c Connection.
2437 * @param buffer How many more messages the connection can accept.
2438 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
2441 GMC_allow (struct MeshConnection *c, unsigned int buffer, int fwd)
2443 send_ack (c, buffer, fwd, GNUNET_NO);
2448 * Notify other peers on a connection of a broken link. Mark connections
2449 * to destroy after all traffic has been sent.
2451 * @param c Connection on which there has been a disconnection.
2452 * @param peer Peer that disconnected.
2455 GMC_notify_broken (struct MeshConnection *c,
2456 struct MeshPeer *peer)
2460 LOG (GNUNET_ERROR_TYPE_DEBUG,
2461 " notify broken on %s due to %s disconnect\n",
2462 GMC_2s (c), GMP_2s (peer));
2464 fwd = peer == get_prev_hop (c);
2466 if (GNUNET_YES == GMC_is_terminal (c, fwd))
2468 /* Local shutdown, no one to notify about this. */
2472 if (GNUNET_NO == c->destroy)
2473 send_broken (c, &my_full_id, GMP_get_id (peer), fwd);
2475 /* Connection will have at least one pending message
2476 * (the one we just scheduled), so no point in checking whether to
2477 * destroy immediately. */
2478 c->destroy = GNUNET_YES;
2479 c->state = MESH_CONNECTION_DESTROYED;
2482 * Cancel all queues, if no message is left, connection will be destroyed.
2484 connection_cancel_queues (c, !fwd);
2491 * Is this peer the first one on the connection?
2493 * @param c Connection.
2494 * @param fwd Is this about fwd traffic?
2496 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
2499 GMC_is_origin (struct MeshConnection *c, int fwd)
2501 if (!fwd && c->path->length - 1 == c->own_pos )
2503 if (fwd && 0 == c->own_pos)
2510 * Is this peer the last one on the connection?
2512 * @param c Connection.
2513 * @param fwd Is this about fwd traffic?
2514 * Note that the ROOT is the terminal for BCK traffic!
2516 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
2519 GMC_is_terminal (struct MeshConnection *c, int fwd)
2521 return GMC_is_origin (c, !fwd);
2526 * See if we are allowed to send by the next hop in the given direction.
2528 * @param c Connection.
2529 * @param fwd Is this about fwd traffic?
2531 * @return #GNUNET_YES in case it's OK to send.
2534 GMC_is_sendable (struct MeshConnection *c, int fwd)
2536 struct MeshFlowControl *fc;
2538 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2539 if (GM_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2545 * Sends an already built message on a connection, properly registering
2546 * all used resources.
2548 * @param message Message to send. Function makes a copy of it.
2549 * If message is not hop-by-hop, decrements TTL of copy.
2550 * @param c Connection on which this message is transmitted.
2551 * @param fwd Is this a fwd message?
2552 * @param force Force the connection to accept the message (buffer overfill).
2553 * @param cont Continuation called once message is sent. Can be NULL.
2554 * @param cont_cls Closure for @c cont.
2556 * @return Handle to cancel the message before it's sent.
2557 * NULL on error or if @c cont is NULL.
2558 * Invalid on @c cont call.
2560 struct MeshConnectionQueue *
2561 GMC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2562 struct MeshConnection *c, int fwd, int force,
2563 GMC_sent cont, void *cont_cls)
2565 struct MeshFlowControl *fc;
2566 struct MeshConnectionQueue *q;
2572 size = ntohs (message->size);
2573 data = GNUNET_malloc (size);
2574 memcpy (data, message, size);
2575 type = ntohs (message->type);
2576 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send %s (%u bytes) on connection %s\n",
2577 GM_m2s (type), size, GMC_2s (c));
2579 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2580 droppable = GNUNET_NO == force;
2583 struct GNUNET_MESH_Encrypted *emsg;
2584 struct GNUNET_MESH_KX *kmsg;
2585 struct GNUNET_MESH_ACK *amsg;
2586 struct GNUNET_MESH_Poll *pmsg;
2587 struct GNUNET_MESH_ConnectionDestroy *dmsg;
2588 struct GNUNET_MESH_ConnectionBroken *bmsg;
2591 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
2592 emsg = (struct GNUNET_MESH_Encrypted *) data;
2593 ttl = ntohl (emsg->ttl);
2596 GNUNET_break_op (0);
2601 emsg->ttl = htonl (ttl - 1);
2602 emsg->pid = htonl (fc->next_pid++);
2603 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
2604 if (GNUNET_YES == droppable)
2607 LOG (GNUNET_ERROR_TYPE_DEBUG, "pid %u\n", ntohl (emsg->pid));
2608 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
2609 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
2613 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
2615 if (GM_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
2617 GMC_start_poll (c, fwd);
2621 case GNUNET_MESSAGE_TYPE_MESH_KX:
2622 kmsg = (struct GNUNET_MESH_KX *) data;
2626 case GNUNET_MESSAGE_TYPE_MESH_ACK:
2627 amsg = (struct GNUNET_MESH_ACK *) data;
2629 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
2630 droppable = GNUNET_NO;
2633 case GNUNET_MESSAGE_TYPE_MESH_POLL:
2634 pmsg = (struct GNUNET_MESH_Poll *) data;
2636 LOG (GNUNET_ERROR_TYPE_DEBUG, " poll %u\n", ntohl (pmsg->pid));
2637 droppable = GNUNET_NO;
2640 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY:
2641 dmsg = (struct GNUNET_MESH_ConnectionDestroy *) data;
2646 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN:
2647 bmsg = (struct GNUNET_MESH_ConnectionBroken *) data;
2652 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE:
2653 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK:
2654 case GNUNET_MESSAGE_TYPE_MESH_KEEPALIVE:
2663 if (fc->queue_n > fc->queue_max && droppable)
2665 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
2668 LOG (GNUNET_ERROR_TYPE_DEBUG,
2669 "queue full: %u/%u\n",
2670 fc->queue_n, fc->queue_max);
2671 if (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED == type)
2677 return NULL; /* Drop this message */
2680 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u\n", c, c->pending_messages);
2681 c->pending_messages++;
2683 q = GNUNET_new (struct MeshConnectionQueue);
2684 q->forced = !droppable;
2685 q->q = GMP_queue_add (get_hop (c, fwd), data, type, size, c, fwd,
2695 q->cont_cls = cont_cls;
2701 * Cancel a previously sent message while it's in the queue.
2703 * ONLY can be called before the continuation given to the send function
2704 * is called. Once the continuation is called, the message is no longer in the
2707 * @param q Handle to the queue.
2710 GMC_cancel (struct MeshConnectionQueue *q)
2712 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GMC cancel message\n");
2714 /* queue destroy calls message_sent, which calls q->cont and frees q */
2715 GMP_queue_destroy (q->q, GNUNET_YES);
2720 * Sends a CREATE CONNECTION message for a path to a peer.
2721 * Changes the connection and tunnel states if necessary.
2723 * @param connection Connection to create.
2726 GMC_send_create (struct MeshConnection *connection)
2728 enum MeshTunnel3CState state;
2731 size = sizeof (struct GNUNET_MESH_ConnectionCreate);
2732 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
2734 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection create\n");
2735 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
2736 connection, connection->pending_messages);
2737 connection->pending_messages++;
2739 GMP_queue_add (get_next_hop (connection), NULL,
2740 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE,
2741 size, connection, GNUNET_YES, &message_sent, NULL);
2743 state = GMT_get_cstate (connection->t);
2744 if (MESH_TUNNEL3_SEARCHING == state || MESH_TUNNEL3_NEW == state)
2745 GMT_change_cstate (connection->t, MESH_TUNNEL3_WAITING);
2746 if (MESH_CONNECTION_NEW == connection->state)
2747 connection_change_state (connection, MESH_CONNECTION_SENT);
2752 * Send a message to all peers in this connection that the connection
2753 * is no longer valid.
2755 * If some peer should not receive the message, it should be zero'ed out
2756 * before calling this function.
2758 * @param c The connection whose peers to notify.
2761 GMC_send_destroy (struct MeshConnection *c)
2763 struct GNUNET_MESH_ConnectionDestroy msg;
2765 if (GNUNET_YES == c->destroy)
2768 msg.header.size = htons (sizeof (msg));
2769 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY);;
2771 LOG (GNUNET_ERROR_TYPE_DEBUG,
2772 " sending connection destroy for connection %s\n",
2775 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_YES))
2776 GMC_send_prebuilt_message (&msg.header, c,
2777 GNUNET_YES, GNUNET_YES, NULL, NULL);
2778 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_NO))
2779 GMC_send_prebuilt_message (&msg.header, c,
2780 GNUNET_NO, GNUNET_YES, NULL, NULL);
2781 c->destroy = GNUNET_YES;
2782 c->state = MESH_CONNECTION_DESTROYED;
2787 * @brief Start a polling timer for the connection.
2789 * When a neighbor does not accept more traffic on the connection it could be
2790 * caused by a simple congestion or by a lost ACK. Polling enables to check
2791 * for the lastest ACK status for a connection.
2793 * @param c Connection.
2794 * @param fwd Should we poll in the FWD direction?
2797 GMC_start_poll (struct MeshConnection *c, int fwd)
2799 struct MeshFlowControl *fc;
2801 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2802 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL %s requested\n",
2804 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task || NULL != fc->poll_msg)
2806 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** not needed (%u, %p)\n",
2807 fc->poll_task, fc->poll_msg);
2810 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL started on request\n");
2811 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
2818 * @brief Stop polling a connection for ACKs.
2820 * Once we have enough ACKs for future traffic, polls are no longer necessary.
2822 * @param c Connection.
2823 * @param fwd Should we stop the poll in the FWD direction?
2826 GMC_stop_poll (struct MeshConnection *c, int fwd)
2828 struct MeshFlowControl *fc;
2830 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2831 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
2833 GNUNET_SCHEDULER_cancel (fc->poll_task);
2834 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2839 * Get a (static) string for a connection.
2841 * @param c Connection.
2844 GMC_2s (struct MeshConnection *c)
2851 static char buf[128];
2853 sprintf (buf, "%s (->%s)", GNUNET_h2s (&c->id), GMT_2s (c->t));
2856 return GNUNET_h2s (&c->id);