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,
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";
337 case MESH_CONNECTION_DESTROYED:
338 return "MESH_CONNECTION_DESTROYED";
340 return "MESH_CONNECTION_STATE_ERROR";
346 * Initialize a Flow Control structure to the initial state.
348 * @param fc Flow Control structure to initialize.
351 fc_init (struct MeshFlowControl *fc)
354 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
355 fc->last_pid_recv = (uint32_t) -1;
356 fc->last_ack_sent = (uint32_t) 0;
357 fc->last_ack_recv = (uint32_t) 0;
358 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
359 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
361 fc->queue_max = (max_msgs_queue / max_connections) + 1;
368 * @param cid Connection ID.
370 static struct MeshConnection *
371 connection_get (const struct GNUNET_HashCode *cid)
373 return GNUNET_CONTAINER_multihashmap_get (connections, cid);
378 connection_change_state (struct MeshConnection* c,
379 enum MeshConnectionState state)
381 LOG (GNUNET_ERROR_TYPE_DEBUG,
382 "Connection %s state was %s\n",
383 GMC_2s (c), GMC_state2s (c->state));
384 if (MESH_CONNECTION_DESTROYED == c->state)
386 LOG (GNUNET_ERROR_TYPE_DEBUG, "state not changing anymore\n");
389 LOG (GNUNET_ERROR_TYPE_DEBUG,
390 "Connection %s state is now %s\n",
391 GMC_2s (c), GMC_state2s (state));
397 * Callback called when a queued ACK message is sent.
399 * @param cls Closure (FC).
400 * @param c Connection this message was on.
401 * @param q Queue handler this call invalidates.
402 * @param type Type of message sent.
403 * @param fwd Was this a FWD going message?
404 * @param size Size of the message.
408 struct MeshConnection *c,
409 struct MeshConnectionQueue *q,
410 uint16_t type, int fwd, size_t size)
412 struct MeshFlowControl *fc = cls;
419 * Send an ACK on the connection, informing the predecessor about
420 * the available buffer space. Should not be called in case the peer
421 * is origin (no predecessor) in the @c fwd direction.
423 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
424 * the ACK itself goes "back" (dest->root).
426 * @param c Connection on which to send the ACK.
427 * @param buffer How much space free to advertise?
428 * @param fwd Is this FWD ACK? (Going dest -> root)
429 * @param force Don't optimize out.
432 send_ack (struct MeshConnection *c, unsigned int buffer, int fwd, int force)
434 struct MeshFlowControl *next_fc;
435 struct MeshFlowControl *prev_fc;
436 struct GNUNET_MESH_ACK msg;
440 /* If origin, there is no connection to send ACKs. Wrong function! */
441 if (GMC_is_origin (c, fwd))
447 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
448 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
450 LOG (GNUNET_ERROR_TYPE_DEBUG,
451 "connection send %s ack on %s\n",
452 fwd ? "FWD" : "BCK", GMC_2s (c));
454 /* Check if we need to transmit the ACK. */
455 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
456 if (3 < delta && buffer < delta && GNUNET_NO == force)
458 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
459 LOG (GNUNET_ERROR_TYPE_DEBUG,
460 " last pid recv: %u, last ack sent: %u\n",
461 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
465 /* Ok, ACK might be necessary, what PID to ACK? */
466 ack = prev_fc->last_pid_recv + buffer;
467 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
468 LOG (GNUNET_ERROR_TYPE_DEBUG,
469 " last pid %u, last ack %u, qmax %u, q %u\n",
470 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
471 next_fc->queue_max, next_fc->queue_n);
472 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
474 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
478 /* Check if message is already in queue */
479 if (NULL != prev_fc->ack_msg)
481 if (GMC_is_pid_bigger (ack, prev_fc->last_ack_sent))
483 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
484 GMC_cancel (prev_fc->ack_msg);
485 /* GMC_cancel triggers ack_sent(), which clears fc->ack_msg */
489 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
494 prev_fc->last_ack_sent = ack;
496 /* Build ACK message and send on connection */
497 msg.header.size = htons (sizeof (msg));
498 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ACK);
499 msg.ack = htonl (ack);
502 prev_fc->ack_msg = GMC_send_prebuilt_message (&msg.header, c, !fwd,
508 * Callback called when a queued message is sent.
510 * Calculates the average time and connection packet tracking.
512 * @param cls Closure (ConnectionQueue Handle).
513 * @param c Connection this message was on.
514 * @param type Type of message sent.
515 * @param fwd Was this a FWD going message?
516 * @param size Size of the message.
517 * @param wait Time spent waiting for core (only the time for THIS message)
520 message_sent (void *cls,
521 struct MeshConnection *c, uint16_t type,
522 int fwd, size_t size,
523 struct GNUNET_TIME_Relative wait)
525 struct MeshConnectionPerformance *p;
526 struct MeshFlowControl *fc;
527 struct MeshConnectionQueue *q = cls;
530 fc = fwd ? &c->fwd_fc : &c->bck_fc;
531 LOG (GNUNET_ERROR_TYPE_DEBUG,
534 GNUNET_MESH_DEBUG_M2S (type));
535 LOG (GNUNET_ERROR_TYPE_DEBUG, "! C_P- %p %u\n", c, c->pending_messages);
540 LOG (GNUNET_ERROR_TYPE_DEBUG, "! calling cont\n");
541 q->cont (q->cont_cls, c, q, type, fwd, size);
545 c->pending_messages--;
546 if (GNUNET_YES == c->destroy && 0 == c->pending_messages)
548 LOG (GNUNET_ERROR_TYPE_DEBUG, "! destroying connection!\n");
552 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
555 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
557 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
559 LOG (GNUNET_ERROR_TYPE_DEBUG,
560 "! accounting pid %u\n",
562 GMC_send_ack (c, fwd, GNUNET_NO);
565 case GNUNET_MESSAGE_TYPE_MESH_POLL:
569 case GNUNET_MESSAGE_TYPE_MESH_ACK:
576 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
579 return; /* Only endpoints are interested in timing. */
582 usecsperbyte = ((double) wait.rel_value_us) / size;
583 if (p->size == AVG_MSGS)
585 /* Array is full. Substract oldest value, add new one and store. */
586 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
587 p->usecsperbyte[p->idx] = usecsperbyte;
588 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
592 /* Array not yet full. Add current value to avg and store. */
593 p->usecsperbyte[p->idx] = usecsperbyte;
595 p->avg += p->usecsperbyte[p->idx];
599 p->idx = (p->idx + 1) % AVG_MSGS;
604 * Get the previous hop in a connection
606 * @param c Connection.
608 * @return Previous peer in the connection.
610 static struct MeshPeer *
611 get_prev_hop (const struct MeshConnection *c)
615 LOG (GNUNET_ERROR_TYPE_DEBUG, "Get prev hop, own pos %u\n", c->own_pos);
616 if (0 == c->own_pos || c->path->length < 2)
617 id = c->path->peers[0];
619 id = c->path->peers[c->own_pos - 1];
621 return GMP_get_short (id);
626 * Get the next hop in a connection
628 * @param c Connection.
630 * @return Next peer in the connection.
632 static struct MeshPeer *
633 get_next_hop (const struct MeshConnection *c)
637 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
638 id = c->path->peers[c->path->length - 1];
640 id = c->path->peers[c->own_pos + 1];
642 return GMP_get_short (id);
647 * Get the hop in a connection.
649 * @param c Connection.
650 * @param fwd Next hop?
652 * @return Next peer in the connection.
654 static struct MeshPeer *
655 get_hop (struct MeshConnection *c, int fwd)
658 return get_next_hop (c);
659 return get_prev_hop (c);
664 * Is traffic coming from this sender 'FWD' traffic?
666 * @param c Connection to check.
667 * @param sender Peer identity of neighbor.
669 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
670 * the traffic is 'FWD'.
671 * #GNUNET_NO for BCK.
672 * #GNUNET_SYSERR for errors.
675 is_fwd (const struct MeshConnection *c,
676 const struct GNUNET_PeerIdentity *sender)
680 id = GNUNET_PEER_search (sender);
681 if (GMP_get_short_id (get_prev_hop (c)) == id)
684 if (GMP_get_short_id (get_next_hop (c)) == id)
688 return GNUNET_SYSERR;
693 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
694 * or a first CONNECTION_ACK directed to us.
696 * @param connection Connection to confirm.
697 * @param fwd Should we send it FWD? (root->dest)
698 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
701 send_connection_ack (struct MeshConnection *connection, int fwd)
703 struct MeshTunnel3 *t;
706 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection %s ACK\n",
707 !fwd ? "FWD" : "BCK");
708 GMP_queue_add (get_hop (connection, fwd), NULL,
709 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK,
710 sizeof (struct GNUNET_MESH_ConnectionACK),
711 connection, fwd, &message_sent, NULL);
712 connection->pending_messages++;
713 if (MESH_TUNNEL3_NEW == GMT_get_state (t))
714 GMT_change_state (t, MESH_TUNNEL3_WAITING);
715 if (MESH_CONNECTION_READY != connection->state)
716 connection_change_state (connection, MESH_CONNECTION_SENT);
721 * Send a notification that a connection is broken.
723 * @param c Connection that is broken.
724 * @param id1 Peer that has disconnected.
725 * @param id2 Peer that has disconnected.
726 * @param fwd Direction towards which to send it.
729 send_broken (struct MeshConnection *c,
730 const struct GNUNET_PeerIdentity *id1,
731 const struct GNUNET_PeerIdentity *id2,
734 struct GNUNET_MESH_ConnectionBroken msg;
736 msg.header.size = htons (sizeof (struct GNUNET_MESH_ConnectionBroken));
737 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN);
741 GMC_send_prebuilt_message (&msg.header, c, fwd, NULL, NULL);
747 * Send keepalive packets for a connection.
749 * @param c Connection to keep alive..
750 * @param fwd Is this a FWD keepalive? (owner -> dest).
752 * FIXME use only one type, register in GMC_send_prebuilt_message()
755 connection_keepalive (struct MeshConnection *c, int fwd)
757 struct GNUNET_MESH_ConnectionKeepAlive *msg;
758 size_t size = sizeof (struct GNUNET_MESH_ConnectionKeepAlive);
762 type = fwd ? GNUNET_MESSAGE_TYPE_MESH_FWD_KEEPALIVE :
763 GNUNET_MESSAGE_TYPE_MESH_BCK_KEEPALIVE;
765 LOG (GNUNET_ERROR_TYPE_DEBUG,
766 "sending %s keepalive for connection %s]\n",
767 fwd ? "FWD" : "BCK", GMC_2s (c));
769 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) cbuf;
770 msg->header.size = htons (size);
771 msg->header.type = htons (type);
774 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
779 * Send CONNECTION_{CREATE/ACK} packets for a connection.
781 * @param c Connection for which to send the message.
782 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
785 connection_recreate (struct MeshConnection *c, int fwd)
787 LOG (GNUNET_ERROR_TYPE_DEBUG, "sending connection recreate\n");
791 send_connection_ack (c, GNUNET_NO);
796 * Generic connection timer management.
797 * Depending on the role of the peer in the connection will send the
798 * appropriate message (build or keepalive)
800 * @param c Conncetion to maintain.
804 connection_maintain (struct MeshConnection *c, int fwd)
806 if (MESH_TUNNEL3_SEARCHING == GMT_get_state (c->t))
808 /* TODO DHT GET with RO_BART */
813 case MESH_CONNECTION_NEW:
816 case MESH_CONNECTION_SENT:
817 connection_recreate (c, fwd);
819 case MESH_CONNECTION_READY:
820 connection_keepalive (c, fwd);
829 connection_fwd_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
831 struct MeshConnection *c = cls;
832 struct GNUNET_TIME_Relative delay;
834 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
835 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
838 connection_maintain (c, GNUNET_YES);
839 delay = c->state == MESH_CONNECTION_READY ?
840 refresh_connection_time : create_connection_time;
841 c->fwd_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
842 &connection_fwd_keepalive,
848 connection_bck_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
850 struct MeshConnection *c = cls;
851 struct GNUNET_TIME_Relative delay;
853 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
854 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
857 connection_maintain (c, GNUNET_NO);
858 delay = c->state == MESH_CONNECTION_READY ?
859 refresh_connection_time : create_connection_time;
860 c->bck_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
861 &connection_bck_keepalive,
867 * @brief Re-initiate traffic on this connection if necessary.
869 * Check if there is traffic queued towards this peer
870 * and the core transmit handle is NULL (traffic was stalled).
871 * If so, call core tmt rdy.
873 * @param c Connection on which initiate traffic.
874 * @param fwd Is this about fwd traffic?
877 connection_unlock_queue (struct MeshConnection *c, int fwd)
879 struct MeshPeer *peer;
881 LOG (GNUNET_ERROR_TYPE_DEBUG,
882 "connection_unlock_queue %s on %s\n",
883 fwd ? "FWD" : "BCK", GMC_2s (c));
885 if (GMC_is_terminal (c, fwd))
887 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal!\n");
891 peer = get_hop (c, fwd);
892 GMP_queue_unlock (peer, c);
897 * Cancel all transmissions that belong to a certain connection.
899 * If the connection is scheduled for destruction and no more messages are left,
900 * the connection will be destroyed by the continuation call.
902 * @param c Connection which to cancel. Might be destroyed during this call.
903 * @param fwd Cancel fwd traffic?
906 connection_cancel_queues (struct MeshConnection *c, int fwd)
908 struct MeshFlowControl *fc;
909 struct MeshPeer *peer;
911 LOG (GNUNET_ERROR_TYPE_DEBUG,
912 " *** Cancel %s queues for connection %s\n",
913 fwd ? "FWD" : "BCK", GMC_2s (c));
920 fc = fwd ? &c->fwd_fc : &c->bck_fc;
921 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
923 GNUNET_SCHEDULER_cancel (fc->poll_task);
924 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
925 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Cancel POLL in ccq for fc %p\n", fc);
927 peer = get_hop (c, fwd);
928 GMP_queue_cancel (peer, c);
933 * Function called if a connection has been stalled for a while,
934 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
936 * @param cls Closure (poll ctx).
937 * @param tc TaskContext.
940 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
944 * Callback called when a queued POLL message is sent.
946 * @param cls Closure (FC).
947 * @param c Connection this message was on.
948 * @param q Queue handler this call invalidates.
949 * @param type Type of message sent.
950 * @param fwd Was this a FWD going message?
951 * @param size Size of the message.
954 poll_sent (void *cls,
955 struct MeshConnection *c,
956 struct MeshConnectionQueue *q,
957 uint16_t type, int fwd, size_t size)
959 struct MeshFlowControl *fc = cls;
963 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL canceled on shutdown\n");
966 LOG (GNUNET_ERROR_TYPE_DEBUG,
967 " *** POLL sent for , scheduling new one!\n");
969 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
970 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
971 &connection_poll, fc);
972 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
977 * Function called if a connection has been stalled for a while,
978 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
980 * @param cls Closure (poll ctx).
981 * @param tc TaskContext.
984 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
986 struct MeshFlowControl *fc = cls;
987 struct GNUNET_MESH_Poll msg;
988 struct MeshConnection *c;
990 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
991 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
997 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Polling!\n");
998 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** connection [%s]\n", GMC_2s (c));
999 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** %s\n",
1000 fc == &c->fwd_fc ? "FWD" : "BCK");
1002 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_POLL);
1003 msg.header.size = htons (sizeof (msg));
1004 msg.pid = htonl (fc->last_pid_sent);
1005 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** last pid sent: %u!\n", fc->last_pid_sent);
1006 fc->poll_msg = GMC_send_prebuilt_message (&msg.header, c, fc == &c->fwd_fc,
1012 * Timeout function due to lack of keepalive/traffic from the owner.
1013 * Destroys connection if called.
1015 * @param cls Closure (connection to destroy).
1016 * @param tc TaskContext.
1019 connection_fwd_timeout (void *cls,
1020 const struct GNUNET_SCHEDULER_TaskContext *tc)
1022 struct MeshConnection *c = cls;
1024 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1025 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1027 LOG (GNUNET_ERROR_TYPE_DEBUG,
1028 "Connection %s[%X] FWD timed out. Destroying.\n",
1032 if (GMC_is_origin (c, GNUNET_YES)) /* If local, leave. */
1040 * Timeout function due to lack of keepalive/traffic from the destination.
1041 * Destroys connection if called.
1043 * @param cls Closure (connection to destroy).
1044 * @param tc TaskContext
1047 connection_bck_timeout (void *cls,
1048 const struct GNUNET_SCHEDULER_TaskContext *tc)
1050 struct MeshConnection *c = cls;
1052 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1053 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1056 LOG (GNUNET_ERROR_TYPE_DEBUG,
1057 "Connection %s[%X] FWD timed out. Destroying.\n",
1058 GMT_2s (c->t), c->id);
1060 if (GMC_is_origin (c, GNUNET_NO)) /* If local, leave. */
1068 * Resets the connection timeout task, some other message has done the
1070 * - For the first peer on the direction this means to send
1071 * a keepalive or a path confirmation message (either create or ACK).
1072 * - For all other peers, this means to destroy the connection,
1073 * due to lack of activity.
1074 * Starts the tiemout if no timeout was running (connection just created).
1076 * @param c Connection whose timeout to reset.
1077 * @param fwd Is this forward?
1079 * TODO use heap to improve efficiency of scheduler.
1082 connection_reset_timeout (struct MeshConnection *c, int fwd)
1084 GNUNET_SCHEDULER_TaskIdentifier *ti;
1085 GNUNET_SCHEDULER_Task f;
1087 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1089 if (GNUNET_SCHEDULER_NO_TASK != *ti)
1090 GNUNET_SCHEDULER_cancel (*ti);
1092 if (GMC_is_origin (c, fwd)) /* Startpoint */
1094 f = fwd ? &connection_fwd_keepalive : &connection_bck_keepalive;
1095 *ti = GNUNET_SCHEDULER_add_delayed (refresh_connection_time, f, c);
1097 else /* Relay, endpoint. */
1099 struct GNUNET_TIME_Relative delay;
1101 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1102 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1103 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1109 * Add the connection to the list of both neighbors.
1111 * @param c Connection.
1113 * @return #GNUNET_OK if everything went fine
1114 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1117 register_neighbors (struct MeshConnection *c)
1119 struct MeshPeer *next_peer;
1120 struct MeshPeer *prev_peer;
1122 next_peer = get_next_hop (c);
1123 prev_peer = get_prev_hop (c);
1125 if (GNUNET_NO == GMP_is_neighbor (next_peer)
1126 || GNUNET_NO == GMP_is_neighbor (prev_peer))
1127 return GNUNET_SYSERR;
1129 GMP_add_connection (next_peer, c);
1130 GMP_add_connection (prev_peer, c);
1137 * Remove the connection from the list of both neighbors.
1139 * @param c Connection.
1142 unregister_neighbors (struct MeshConnection *c)
1144 struct MeshPeer *peer;
1146 peer = get_next_hop (c);
1147 GMP_remove_connection (peer, c);
1149 peer = get_prev_hop (c);
1150 GMP_remove_connection (peer, c);
1156 * Bind the connection to the peer and the tunnel to that peer.
1158 * If the peer has no tunnel, create one. Update tunnel and connection
1159 * data structres to reflect new status.
1161 * @param c Connection.
1165 add_to_peer (struct MeshConnection *c, struct MeshPeer *peer)
1167 GMP_add_tunnel (peer);
1168 c->t = GMP_get_tunnel (peer);
1169 GMT_add_connection (c->t, c);
1172 /******************************************************************************/
1173 /******************************** API ***********************************/
1174 /******************************************************************************/
1177 * Core handler for connection creation.
1179 * @param cls Closure (unused).
1180 * @param peer Sender (neighbor).
1181 * @param message Message.
1183 * @return GNUNET_OK to keep the connection open,
1184 * GNUNET_SYSERR to close it (signal serious error)
1187 GMC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
1188 const struct GNUNET_MessageHeader *message)
1190 struct GNUNET_MESH_ConnectionCreate *msg;
1191 struct GNUNET_PeerIdentity *id;
1192 struct GNUNET_HashCode *cid;
1193 struct MeshPeerPath *path;
1194 struct MeshPeer *dest_peer;
1195 struct MeshPeer *orig_peer;
1196 struct MeshConnection *c;
1197 unsigned int own_pos;
1201 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1202 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection create msg\n");
1205 size = ntohs (message->size);
1206 if (size < sizeof (struct GNUNET_MESH_ConnectionCreate))
1208 GNUNET_break_op (0);
1212 /* Calculate hops */
1213 size -= sizeof (struct GNUNET_MESH_ConnectionCreate);
1214 if (size % sizeof (struct GNUNET_PeerIdentity))
1216 GNUNET_break_op (0);
1219 size /= sizeof (struct GNUNET_PeerIdentity);
1222 GNUNET_break_op (0);
1225 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1227 /* Get parameters */
1228 msg = (struct GNUNET_MESH_ConnectionCreate *) message;
1230 id = (struct GNUNET_PeerIdentity *) &msg[1];
1231 LOG (GNUNET_ERROR_TYPE_DEBUG,
1232 " connection %s (%s).\n",
1233 GNUNET_h2s (cid), GNUNET_i2s (id));
1235 /* Create connection */
1236 c = connection_get (cid);
1240 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating path...\n");
1241 path = path_new (size);
1243 for (i = 0; i < size; i++)
1245 LOG (GNUNET_ERROR_TYPE_DEBUG, " ... adding %s\n",
1246 GNUNET_i2s (&id[i]));
1247 path->peers[i] = GNUNET_PEER_intern (&id[i]);
1248 if (path->peers[i] == myid)
1251 if (own_pos == 0 && path->peers[own_pos] != myid)
1253 /* create path: self not found in path through self */
1254 GNUNET_break_op (0);
1255 path_destroy (path);
1258 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1259 GMP_add_path_to_all (path, GNUNET_NO);
1260 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1261 c = GMC_new (cid, NULL, path_duplicate (path), own_pos);
1264 path_destroy (path);
1267 connection_reset_timeout (c, GNUNET_YES);
1271 path = path_duplicate (c->path);
1273 if (MESH_CONNECTION_NEW == c->state)
1274 connection_change_state (c, MESH_CONNECTION_SENT);
1276 /* Remember peers */
1277 dest_peer = GMP_get (&id[size - 1]);
1278 orig_peer = GMP_get (&id[0]);
1280 /* Is it a connection to us? */
1281 if (c->own_pos == size - 1)
1283 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1284 GMP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
1286 add_to_peer (c, orig_peer);
1287 if (MESH_TUNNEL3_NEW == GMT_get_state (c->t))
1288 GMT_change_state (c->t, MESH_TUNNEL3_WAITING);
1290 send_connection_ack (c, GNUNET_NO);
1291 if (MESH_CONNECTION_SENT == c->state)
1292 connection_change_state (c, MESH_CONNECTION_ACK);
1294 /* Keep tunnel alive in direction dest->owner*/
1295 c->bck_maintenance_task =
1296 GNUNET_SCHEDULER_add_delayed (create_connection_time,
1297 &connection_bck_keepalive, c);
1301 /* It's for somebody else! Retransmit. */
1302 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
1303 GMP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1304 GMP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
1305 GMC_send_prebuilt_message (message, c, GNUNET_YES, NULL, NULL);
1307 path_destroy (path);
1313 * Core handler for path confirmations.
1315 * @param cls closure
1316 * @param message message
1317 * @param peer peer identity this notification is about
1319 * @return GNUNET_OK to keep the connection open,
1320 * GNUNET_SYSERR to close it (signal serious error)
1323 GMC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
1324 const struct GNUNET_MessageHeader *message)
1326 struct GNUNET_MESH_ConnectionACK *msg;
1327 struct MeshConnection *c;
1328 struct MeshPeerPath *p;
1329 struct MeshPeer *pi;
1330 enum MeshConnectionState oldstate;
1333 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1334 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection ACK msg\n");
1335 msg = (struct GNUNET_MESH_ConnectionACK *) message;
1336 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n",
1337 GNUNET_h2s (&msg->cid));
1338 c = connection_get (&msg->cid);
1341 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1343 LOG (GNUNET_ERROR_TYPE_DEBUG, " don't know the connection!\n");
1347 oldstate = c->state;
1348 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
1349 pi = GMP_get (peer);
1350 if (get_next_hop (c) == pi)
1352 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
1354 if (MESH_CONNECTION_SENT == oldstate)
1355 connection_change_state (c, MESH_CONNECTION_ACK);
1357 else if (get_prev_hop (c) == pi)
1359 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK\n");
1361 connection_change_state (c, MESH_CONNECTION_READY);
1365 GNUNET_break_op (0);
1369 connection_reset_timeout (c, fwd);
1371 /* Add path to peers? */
1375 GMP_add_path_to_all (p, GNUNET_YES);
1382 /* Message for us as creator? */
1383 if (GMC_is_origin (c, GNUNET_YES))
1385 if (GNUNET_NO != fwd)
1387 GNUNET_break_op (0);
1390 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
1392 /* If just created, cancel the short timeout and start a long one */
1393 if (MESH_CONNECTION_SENT == oldstate)
1394 connection_reset_timeout (c, GNUNET_YES);
1396 /* Change connection and tunnel state */
1397 connection_change_state (c, MESH_CONNECTION_READY);
1398 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1399 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1401 /* Send ACK (~TCP ACK)*/
1402 send_connection_ack (c, GNUNET_YES);
1406 /* Message for us as destination? */
1407 if (GMC_is_terminal (c, GNUNET_YES))
1409 if (GNUNET_YES != fwd)
1411 GNUNET_break_op (0);
1414 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
1416 /* If just created, cancel the short timeout and start a long one */
1417 if (MESH_CONNECTION_ACK == oldstate)
1418 connection_reset_timeout (c, GNUNET_NO);
1420 /* Change tunnel state */
1421 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1422 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1427 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1428 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1434 * Core handler for notifications of broken paths
1436 * @param cls Closure (unused).
1437 * @param id Peer identity of sending neighbor.
1438 * @param message Message.
1440 * @return GNUNET_OK to keep the connection open,
1441 * GNUNET_SYSERR to close it (signal serious error)
1444 GMC_handle_broken (void* cls,
1445 const struct GNUNET_PeerIdentity* id,
1446 const struct GNUNET_MessageHeader* message)
1448 struct GNUNET_MESH_ConnectionBroken *msg;
1449 struct MeshConnection *c;
1452 LOG (GNUNET_ERROR_TYPE_DEBUG,
1453 "Received a CONNECTION BROKEN msg from %s\n", GNUNET_i2s (id));
1454 msg = (struct GNUNET_MESH_ConnectionBroken *) message;
1455 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1456 GNUNET_i2s (&msg->peer1));
1457 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1458 GNUNET_i2s (&msg->peer2));
1459 c = connection_get (&msg->cid);
1462 GNUNET_break_op (0);
1466 fwd = is_fwd (c, id);
1467 connection_cancel_queues (c, !fwd);
1468 if (GMC_is_terminal (c, fwd))
1470 if (0 < c->pending_messages)
1471 c->destroy = GNUNET_YES;
1477 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1478 c->destroy = GNUNET_YES;
1487 * Core handler for tunnel destruction
1489 * @param cls Closure (unused).
1490 * @param peer Peer identity of sending neighbor.
1491 * @param message Message.
1493 * @return GNUNET_OK to keep the connection open,
1494 * GNUNET_SYSERR to close it (signal serious error)
1497 GMC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
1498 const struct GNUNET_MessageHeader *message)
1500 struct GNUNET_MESH_ConnectionDestroy *msg;
1501 struct MeshConnection *c;
1504 msg = (struct GNUNET_MESH_ConnectionDestroy *) message;
1505 LOG (GNUNET_ERROR_TYPE_DEBUG,
1506 "Got a CONNECTION DESTROY message from %s\n",
1508 LOG (GNUNET_ERROR_TYPE_DEBUG,
1509 " for connection %s\n",
1510 GNUNET_h2s (&msg->cid));
1511 c = connection_get (&msg->cid);
1514 /* Probably already got the message from another path,
1515 * destroyed the tunnel and retransmitted to children.
1518 GNUNET_STATISTICS_update (stats, "# control on unknown tunnel",
1520 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection unknown: already destroyed?\n");
1523 fwd = is_fwd (c, peer);
1524 if (GNUNET_SYSERR == fwd)
1526 GNUNET_break_op (0);
1529 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
1530 c->destroy = GNUNET_YES;
1531 c->state = MESH_CONNECTION_DESTROYED;
1537 * Generic handler for mesh network encrypted traffic.
1539 * @param peer Peer identity this notification is about.
1540 * @param msg Encrypted message.
1542 * @return GNUNET_OK to keep the connection open,
1543 * GNUNET_SYSERR to close it (signal serious error)
1546 handle_mesh_encrypted (const struct GNUNET_PeerIdentity *peer,
1547 const struct GNUNET_MESH_Encrypted *msg)
1549 struct MeshConnection *c;
1550 struct MeshPeer *neighbor;
1551 struct MeshFlowControl *fc;
1552 GNUNET_PEER_Id peer_id;
1560 size = ntohs (msg->header.size);
1562 sizeof (struct GNUNET_MESH_Encrypted) +
1563 sizeof (struct GNUNET_MessageHeader))
1565 GNUNET_break_op (0);
1568 type = ntohs (msg->header.type);
1569 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1570 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message (#%u) from %s\n",
1571 GNUNET_MESH_DEBUG_M2S (type), ntohl (msg->pid), GNUNET_i2s (peer));
1573 /* Check connection */
1574 c = connection_get (&msg->cid);
1577 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1578 LOG (GNUNET_ERROR_TYPE_DEBUG,
1579 "WARNING connection %s unknown\n",
1580 GNUNET_h2s (&msg->cid));
1584 /* Check if origin is as expected */
1585 neighbor = get_prev_hop (c);
1586 peer_id = GNUNET_PEER_search (peer);
1587 if (peer_id == GMP_get_short_id (neighbor))
1593 neighbor = get_next_hop (c);
1594 if (peer_id == GMP_get_short_id (neighbor))
1600 /* Unexpected peer sending traffic on a connection. */
1601 GNUNET_break_op (0);
1607 fc = fwd ? &c->bck_fc : &c->fwd_fc;
1608 pid = ntohl (msg->pid);
1609 if (GMC_is_pid_bigger (pid, fc->last_ack_sent))
1611 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
1612 LOG (GNUNET_ERROR_TYPE_DEBUG,
1613 "WARNING Received PID %u, (prev %u), ACK %u\n",
1614 pid, fc->last_pid_recv, fc->last_ack_sent);
1617 if (GNUNET_NO == GMC_is_pid_bigger (pid, fc->last_pid_recv))
1619 GNUNET_STATISTICS_update (stats, "# duplicate PID", 1, GNUNET_NO);
1620 LOG (GNUNET_ERROR_TYPE_DEBUG,
1621 " Pid %u not expected (%u+), dropping!\n",
1622 pid, fc->last_pid_recv + 1);
1625 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1626 connection_change_state (c, MESH_CONNECTION_READY);
1627 connection_reset_timeout (c, fwd);
1628 fc->last_pid_recv = pid;
1630 /* Is this message for us? */
1631 if (GMC_is_terminal (c, fwd))
1633 /* TODO signature verification */
1634 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1635 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1642 fc->last_pid_recv = pid;
1643 GMT_handle_encrypted (c->t, msg);
1644 GMC_send_ack (c, fwd, GNUNET_NO);
1648 /* Message not for us: forward to next hop */
1649 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1650 ttl = ntohl (msg->ttl);
1651 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
1654 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
1655 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
1656 GMC_send_ack (c, fwd, GNUNET_NO);
1660 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1661 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
1667 * Generic handler for mesh network encrypted traffic.
1669 * @param peer Peer identity this notification is about.
1670 * @param msg Encrypted message.
1672 * @return GNUNET_OK to keep the connection open,
1673 * GNUNET_SYSERR to close it (signal serious error)
1676 handle_mesh_kx (const struct GNUNET_PeerIdentity *peer,
1677 const struct GNUNET_MESH_KX *msg)
1679 struct MeshConnection *c;
1680 struct MeshPeer *neighbor;
1681 GNUNET_PEER_Id peer_id;
1687 size = ntohs (msg->header.size);
1689 sizeof (struct GNUNET_MESH_Encrypted) +
1690 sizeof (struct GNUNET_MessageHeader))
1692 GNUNET_break_op (0);
1695 type = ntohs (msg->header.type);
1696 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1697 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message from %s\n",
1698 GNUNET_MESH_DEBUG_M2S (type), GNUNET_i2s (peer));
1700 /* Check connection */
1701 c = connection_get (&msg->cid);
1704 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1705 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING connection unknown\n");
1709 /* Check if origin is as expected */
1710 neighbor = get_prev_hop (c);
1711 peer_id = GNUNET_PEER_search (peer);
1712 if (peer_id == GMP_get_short_id (neighbor))
1718 neighbor = get_next_hop (c);
1719 if (peer_id == GMP_get_short_id (neighbor))
1725 /* Unexpected peer sending traffic on a connection. */
1726 GNUNET_break_op (0);
1731 /* Count as connection confirmation. */
1732 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1733 connection_change_state (c, MESH_CONNECTION_READY);
1734 connection_reset_timeout (c, fwd);
1737 if (MESH_TUNNEL3_WAITING == GMT_get_state (c->t))
1738 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1741 /* Is this message for us? */
1742 if (GMC_is_terminal (c, fwd))
1744 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1745 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1751 GMT_handle_kx (c->t, &msg[1].header);
1755 /* Message not for us: forward to next hop */
1756 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1757 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1758 GMC_send_prebuilt_message (&msg->header, c, fwd, NULL, NULL);
1765 * Core handler for encrypted mesh network traffic (channel mgmt, data).
1767 * @param cls Closure (unused).
1768 * @param message Message received.
1769 * @param peer Peer who sent the message.
1771 * @return GNUNET_OK to keep the connection open,
1772 * GNUNET_SYSERR to close it (signal serious error)
1775 GMC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
1776 const struct GNUNET_MessageHeader *message)
1778 return handle_mesh_encrypted (peer,
1779 (struct GNUNET_MESH_Encrypted *)message);
1784 * Core handler for key exchange traffic (ephemeral key, ping, pong).
1786 * @param cls Closure (unused).
1787 * @param message Message received.
1788 * @param peer Peer who sent the message.
1790 * @return GNUNET_OK to keep the connection open,
1791 * GNUNET_SYSERR to close it (signal serious error)
1794 GMC_handle_kx (void *cls, const struct GNUNET_PeerIdentity *peer,
1795 const struct GNUNET_MessageHeader *message)
1797 return handle_mesh_kx (peer,
1798 (struct GNUNET_MESH_KX *) message);
1803 * Core handler for mesh network traffic point-to-point acks.
1805 * @param cls closure
1806 * @param message message
1807 * @param peer peer identity this notification is about
1809 * @return GNUNET_OK to keep the connection open,
1810 * GNUNET_SYSERR to close it (signal serious error)
1813 GMC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
1814 const struct GNUNET_MessageHeader *message)
1816 struct GNUNET_MESH_ACK *msg;
1817 struct MeshConnection *c;
1818 struct MeshFlowControl *fc;
1823 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1824 LOG (GNUNET_ERROR_TYPE_DEBUG, "Got an ACK packet from %s!\n",
1826 msg = (struct GNUNET_MESH_ACK *) message;
1828 c = connection_get (&msg->cid);
1832 GNUNET_STATISTICS_update (stats, "# ack on unknown connection", 1,
1837 /* Is this a forward or backward ACK? */
1838 id = GNUNET_PEER_search (peer);
1839 if (GMP_get_short_id (get_next_hop (c)) == id)
1841 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
1845 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1847 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
1853 GNUNET_break_op (0);
1857 ack = ntohl (msg->ack);
1858 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u (was %u)\n",
1859 ack, fc->last_ack_recv);
1860 if (GMC_is_pid_bigger (ack, fc->last_ack_recv))
1861 fc->last_ack_recv = ack;
1863 /* Cancel polling if the ACK is big enough. */
1864 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task &&
1865 GMC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
1867 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
1868 GNUNET_SCHEDULER_cancel (fc->poll_task);
1869 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1870 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
1873 connection_unlock_queue (c, fwd);
1880 * Core handler for mesh network traffic point-to-point ack polls.
1882 * @param cls closure
1883 * @param message message
1884 * @param peer peer identity this notification is about
1886 * @return GNUNET_OK to keep the connection open,
1887 * GNUNET_SYSERR to close it (signal serious error)
1890 GMC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
1891 const struct GNUNET_MessageHeader *message)
1893 struct GNUNET_MESH_Poll *msg;
1894 struct MeshConnection *c;
1895 struct MeshFlowControl *fc;
1900 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1901 LOG (GNUNET_ERROR_TYPE_DEBUG,
1902 "Got a POLL packet from %s!\n",
1905 msg = (struct GNUNET_MESH_Poll *) message;
1907 c = connection_get (&msg->cid);
1911 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
1913 GNUNET_break_op (0);
1917 /* Is this a forward or backward ACK?
1918 * Note: a poll should never be needed in a loopback case,
1919 * since there is no possiblility of packet loss there, so
1920 * this way of discerining FWD/BCK should not be a problem.
1922 id = GNUNET_PEER_search (peer);
1923 if (GMP_get_short_id (get_next_hop (c)) == id)
1925 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
1928 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1930 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
1935 GNUNET_break_op (0);
1939 pid = ntohl (msg->pid);
1940 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
1941 fc->last_pid_recv = pid;
1942 fwd = fc == &c->bck_fc;
1943 GMC_send_ack (c, fwd, GNUNET_YES);
1950 * Core handler for mesh keepalives.
1952 * @param cls closure
1953 * @param message message
1954 * @param peer peer identity this notification is about
1955 * @return GNUNET_OK to keep the connection open,
1956 * GNUNET_SYSERR to close it (signal serious error)
1958 * TODO: Check who we got this from, to validate route.
1961 GMC_handle_keepalive (void *cls, const struct GNUNET_PeerIdentity *peer,
1962 const struct GNUNET_MessageHeader *message)
1964 struct GNUNET_MESH_ConnectionKeepAlive *msg;
1965 struct MeshConnection *c;
1966 struct MeshPeer *neighbor;
1969 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) message;
1970 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a keepalive packet from %s\n",
1973 c = connection_get (&msg->cid);
1976 GNUNET_STATISTICS_update (stats, "# keepalive on unknown connection", 1,
1981 fwd = GNUNET_MESSAGE_TYPE_MESH_FWD_KEEPALIVE == ntohs (message->type) ?
1982 GNUNET_YES : GNUNET_NO;
1984 /* Check if origin is as expected */
1985 neighbor = get_hop (c, fwd);
1986 if (GNUNET_PEER_search (peer) != GMP_get_short_id (neighbor))
1988 GNUNET_break_op (0);
1992 connection_change_state (c, MESH_CONNECTION_READY);
1993 connection_reset_timeout (c, fwd);
1995 if (GMC_is_terminal (c, fwd))
1998 GNUNET_STATISTICS_update (stats, "# keepalives forwarded", 1, GNUNET_NO);
1999 GMC_send_prebuilt_message (message, c, fwd, NULL, NULL);
2006 * Send an ACK on the appropriate connection/channel, depending on
2007 * the direction and the position of the peer.
2009 * @param c Which connection to send the hop-by-hop ACK.
2010 * @param fwd Is this a fwd ACK? (will go dest->root).
2011 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2014 GMC_send_ack (struct MeshConnection *c, int fwd, int force)
2016 unsigned int buffer;
2018 LOG (GNUNET_ERROR_TYPE_DEBUG,
2019 "GMC send %s ACK on %s\n",
2020 fwd ? "FWD" : "BCK", GMC_2s (c));
2028 if (GNUNET_NO != c->destroy)
2030 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2034 /* Get available buffer space */
2035 if (GMC_is_terminal (c, fwd))
2037 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2038 buffer = GMT_get_channels_buffer (c->t);
2042 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2043 buffer = GMC_get_buffer (c, fwd);
2045 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2046 if (0 == buffer && GNUNET_NO == force)
2049 /* Send available buffer space */
2050 if (GMC_is_origin (c, fwd))
2052 GNUNET_assert (NULL != c->t);
2053 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2054 GMT_unchoke_channels (c->t);
2058 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2059 send_ack (c, buffer, fwd, force);
2065 * Initialize the connections subsystem
2067 * @param c Configuration handle.
2070 GMC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2072 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2074 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_MSGS_QUEUE",
2077 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2078 "MESH", "MAX_MSGS_QUEUE", "MISSING");
2079 GNUNET_SCHEDULER_shutdown ();
2084 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_CONNECTIONS",
2087 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2088 "MESH", "MAX_CONNECTIONS", "MISSING");
2089 GNUNET_SCHEDULER_shutdown ();
2094 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REFRESH_CONNECTION_TIME",
2095 &refresh_connection_time))
2097 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2098 "MESH", "REFRESH_CONNECTION_TIME", "MISSING");
2099 GNUNET_SCHEDULER_shutdown ();
2102 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2103 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_YES);
2108 * Destroy each connection on shutdown.
2110 * @param cls Closure (unused).
2111 * @param key Current key code (CID, unused).
2112 * @param value Value in the hash map (connection)
2114 * @return #GNUNET_YES, because we should continue to iterate,
2117 shutdown_iterator (void *cls,
2118 const struct GNUNET_HashCode *key,
2121 struct MeshConnection *c = value;
2129 * Shut down the connections subsystem.
2134 GNUNET_CONTAINER_multihashmap_iterate (connections, &shutdown_iterator, NULL);
2135 GNUNET_CONTAINER_multihashmap_destroy (connections);
2140 struct MeshConnection *
2141 GMC_new (const struct GNUNET_HashCode *cid,
2142 struct MeshTunnel3 *t,
2143 struct MeshPeerPath *p,
2144 unsigned int own_pos)
2146 struct MeshConnection *c;
2148 c = GNUNET_new (struct MeshConnection);
2150 GNUNET_CONTAINER_multihashmap_put (connections, &c->id, c,
2151 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST);
2152 fc_init (&c->fwd_fc);
2153 fc_init (&c->bck_fc);
2158 if (own_pos > p->length - 1)
2164 c->own_pos = own_pos;
2169 c->fwd_maintenance_task =
2170 GNUNET_SCHEDULER_add_delayed (create_connection_time,
2171 &connection_fwd_keepalive, c);
2173 if (GNUNET_OK != register_neighbors (c))
2184 GMC_destroy (struct MeshConnection *c)
2189 if (2 == c->destroy) /* cancel queues -> GMP_queue_cancel -> q_destroy -> */
2190 return; /* -> message_sent -> GMC_destroy. Don't loop. */
2193 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying connection %s\n", GMC_2s (c));
2194 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc's f: %p, b: %p\n",
2195 &c->fwd_fc, &c->bck_fc);
2196 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2197 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2199 /* Cancel all traffic */
2200 connection_cancel_queues (c, GNUNET_YES);
2201 connection_cancel_queues (c, GNUNET_NO);
2203 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2204 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2206 /* Cancel maintainance task (keepalive/timeout) */
2207 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_maintenance_task)
2208 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2209 if (GNUNET_SCHEDULER_NO_TASK != c->bck_maintenance_task)
2210 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2211 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_fc.poll_task)
2213 GNUNET_SCHEDULER_cancel (c->fwd_fc.poll_task);
2214 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL FWD canceled\n");
2216 if (GNUNET_SCHEDULER_NO_TASK != c->bck_fc.poll_task)
2218 GNUNET_SCHEDULER_cancel (c->bck_fc.poll_task);
2219 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL BCK canceled\n");
2221 if (NULL != c->fwd_fc.poll_msg)
2223 GMC_cancel (c->fwd_fc.poll_msg);
2224 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg FWD canceled\n");
2226 if (NULL != c->bck_fc.poll_msg)
2228 GMC_cancel (c->bck_fc.poll_msg);
2229 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg BCK canceled\n");
2232 /* Unregister from neighbors */
2233 unregister_neighbors (c);
2236 GNUNET_STATISTICS_update (stats, "# connections", -1, GNUNET_NO);
2238 GMT_remove_connection (c->t, c);
2240 if (GNUNET_NO == GMC_is_origin (c, GNUNET_YES))
2241 path_destroy (c->path);
2243 GNUNET_break (GNUNET_YES ==
2244 GNUNET_CONTAINER_multihashmap_remove (connections, &c->id, c));
2250 * Get the connection ID.
2252 * @param c Connection to get the ID from.
2254 * @return ID of the connection.
2256 const struct GNUNET_HashCode *
2257 GMC_get_id (const struct MeshConnection *c)
2264 * Get the connection path.
2266 * @param c Connection to get the path from.
2268 * @return path used by the connection.
2270 const struct MeshPeerPath *
2271 GMC_get_path (const struct MeshConnection *c)
2278 * Get the connection state.
2280 * @param c Connection to get the state from.
2282 * @return state of the connection.
2284 enum MeshConnectionState
2285 GMC_get_state (const struct MeshConnection *c)
2291 * Get the connection tunnel.
2293 * @param c Connection to get the tunnel from.
2295 * @return tunnel of the connection.
2297 struct MeshTunnel3 *
2298 GMC_get_tunnel (const struct MeshConnection *c)
2305 * Get free buffer space in a connection.
2307 * @param c Connection.
2308 * @param fwd Is query about FWD traffic?
2310 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2313 GMC_get_buffer (struct MeshConnection *c, int fwd)
2315 struct MeshFlowControl *fc;
2317 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2319 return (fc->queue_max - fc->queue_n);
2323 * Get how many messages have we allowed to send to us from a direction.
2325 * @param c Connection.
2326 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2328 * @return last_ack_sent - last_pid_recv
2331 GMC_get_allowed (struct MeshConnection *c, int fwd)
2333 struct MeshFlowControl *fc;
2335 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2336 if (GMC_is_pid_bigger(fc->last_pid_recv, fc->last_ack_sent))
2340 return (fc->last_ack_sent - fc->last_pid_recv);
2344 * Get messages queued in a connection.
2346 * @param c Connection.
2347 * @param fwd Is query about FWD traffic?
2349 * @return Number of messages queued.
2352 GMC_get_qn (struct MeshConnection *c, int fwd)
2354 struct MeshFlowControl *fc;
2356 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2363 * Allow the connection to advertise a buffer of the given size.
2365 * The connection will send an @c fwd ACK message (so: in direction !fwd)
2366 * allowing up to last_pid_recv + buffer.
2368 * @param c Connection.
2369 * @param buffer How many more messages the connection can accept.
2370 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
2373 GMC_allow (struct MeshConnection *c, unsigned int buffer, int fwd)
2375 send_ack (c, buffer, fwd, GNUNET_NO);
2380 * Notify other peers on a connection of a broken link. Mark connections
2381 * to destroy after all traffic has been sent.
2383 * @param c Connection on which there has been a disconnection.
2384 * @param peer Peer that disconnected.
2387 GMC_notify_broken (struct MeshConnection *c,
2388 struct MeshPeer *peer)
2392 LOG (GNUNET_ERROR_TYPE_DEBUG,
2393 " notify broken on %s due to %s disconnect\n",
2394 GMC_2s (c), GMP_2s (peer));
2396 fwd = peer == get_prev_hop (c);
2398 if (GNUNET_YES == GMC_is_terminal (c, fwd))
2400 /* Local shutdown, no one to notify about this. */
2404 if (GNUNET_NO == c->destroy)
2405 send_broken (c, &my_full_id, GMP_get_id (peer), fwd);
2407 /* Connection will have at least one pending message
2408 * (the one we just scheduled), so no point in checking whether to
2409 * destroy immediately. */
2410 c->destroy = GNUNET_YES;
2411 c->state = MESH_CONNECTION_DESTROYED;
2414 * Cancel all queues, if no message is left, connection will be destroyed.
2416 connection_cancel_queues (c, !fwd);
2423 * Is this peer the first one on the connection?
2425 * @param c Connection.
2426 * @param fwd Is this about fwd traffic?
2428 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
2431 GMC_is_origin (struct MeshConnection *c, int fwd)
2433 if (!fwd && c->path->length - 1 == c->own_pos )
2435 if (fwd && 0 == c->own_pos)
2442 * Is this peer the last one on the connection?
2444 * @param c Connection.
2445 * @param fwd Is this about fwd traffic?
2446 * Note that the ROOT is the terminal for BCK traffic!
2448 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
2451 GMC_is_terminal (struct MeshConnection *c, int fwd)
2453 return GMC_is_origin (c, !fwd);
2458 * See if we are allowed to send by the next hop in the given direction.
2460 * @param c Connection.
2461 * @param fwd Is this about fwd traffic?
2463 * @return #GNUNET_YES in case it's OK to send.
2466 GMC_is_sendable (struct MeshConnection *c, int fwd)
2468 struct MeshFlowControl *fc;
2470 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2471 if (GMC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2477 * Sends an already built message on a connection, properly registering
2478 * all used resources.
2480 * @param message Message to send. Function makes a copy of it.
2481 * If message is not hop-by-hop, decrements TTL of copy.
2482 * @param c Connection on which this message is transmitted.
2483 * @param fwd Is this a fwd message?
2484 * @param cont Continuation called once message is sent. Can be NULL.
2485 * @param cont_cls Closure for @c cont.
2487 * @return Handle to cancel the message before it's sent.
2488 * NULL on error or if @c cont is NULL.
2489 * Invalid on @c cont call.
2491 struct MeshConnectionQueue *
2492 GMC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2493 struct MeshConnection *c, int fwd,
2494 GMC_sent cont, void *cont_cls)
2496 struct MeshFlowControl *fc;
2497 struct MeshConnectionQueue *q;
2503 size = ntohs (message->size);
2504 data = GNUNET_malloc (size);
2505 memcpy (data, message, size);
2506 type = ntohs (message->type);
2507 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send %s (%u bytes) on connection %s\n",
2508 GNUNET_MESH_DEBUG_M2S (type), size, GMC_2s (c));
2510 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2511 droppable = GNUNET_YES;
2514 struct GNUNET_MESH_Encrypted *emsg;
2515 struct GNUNET_MESH_KX *kmsg;
2516 struct GNUNET_MESH_ACK *amsg;
2517 struct GNUNET_MESH_Poll *pmsg;
2518 struct GNUNET_MESH_ConnectionDestroy *dmsg;
2519 struct GNUNET_MESH_ConnectionBroken *bmsg;
2522 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
2523 emsg = (struct GNUNET_MESH_Encrypted *) data;
2524 ttl = ntohl (emsg->ttl);
2527 GNUNET_break_op (0);
2532 emsg->ttl = htonl (ttl - 1);
2533 emsg->pid = htonl (fc->next_pid++);
2534 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
2536 LOG (GNUNET_ERROR_TYPE_DEBUG, "pid %u\n", ntohl (emsg->pid));
2537 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
2538 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
2539 if (GMC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
2541 GMC_start_poll (c, fwd);
2545 case GNUNET_MESSAGE_TYPE_MESH_KX:
2546 kmsg = (struct GNUNET_MESH_KX *) data;
2550 case GNUNET_MESSAGE_TYPE_MESH_ACK:
2551 amsg = (struct GNUNET_MESH_ACK *) data;
2553 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
2554 droppable = GNUNET_NO;
2557 case GNUNET_MESSAGE_TYPE_MESH_POLL:
2558 pmsg = (struct GNUNET_MESH_Poll *) data;
2560 LOG (GNUNET_ERROR_TYPE_DEBUG, " poll %u\n", ntohl (pmsg->pid));
2561 droppable = GNUNET_NO;
2564 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY:
2565 dmsg = (struct GNUNET_MESH_ConnectionDestroy *) data;
2570 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN:
2571 bmsg = (struct GNUNET_MESH_ConnectionBroken *) data;
2576 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE:
2577 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK:
2584 if (fc->queue_n > fc->queue_max && droppable)
2586 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
2589 LOG (GNUNET_ERROR_TYPE_DEBUG,
2590 "queue full: %u/%u\n",
2591 fc->queue_n, fc->queue_max);
2592 if (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED == type)
2598 return NULL; /* Drop this message */
2601 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u\n", c, c->pending_messages);
2602 c->pending_messages++;
2606 (void) GMP_queue_add (get_hop (c, fwd), data, type, size, c, fwd,
2607 &message_sent, NULL);
2611 q = GNUNET_new (struct MeshConnectionQueue);
2612 q->q = GMP_queue_add (get_hop (c, fwd), data, type, size, c, fwd,
2622 q->cont_cls = cont_cls;
2628 * Cancel a previously sent message while it's in the queue.
2630 * ONLY can be called before the continuation given to the send function
2631 * is called. Once the continuation is called, the message is no longer in the
2634 * @param q Handle to the queue.
2637 GMC_cancel (struct MeshConnectionQueue *q)
2639 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GMC cancel message\n");
2641 /* queue destroy calls message_sent, which calls q->cont and frees q */
2642 GMP_queue_destroy (q->q, GNUNET_YES);
2647 * Sends a CREATE CONNECTION message for a path to a peer.
2648 * Changes the connection and tunnel states if necessary.
2650 * @param connection Connection to create.
2653 GMC_send_create (struct MeshConnection *connection)
2655 enum MeshTunnel3State state;
2658 size = sizeof (struct GNUNET_MESH_ConnectionCreate);
2659 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
2660 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection create\n");
2661 GMP_queue_add (get_next_hop (connection), NULL,
2662 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE,
2663 size, connection, GNUNET_YES, &message_sent, NULL);
2664 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
2665 connection, connection->pending_messages);
2666 connection->pending_messages++;
2667 state = GMT_get_state (connection->t);
2668 if (MESH_TUNNEL3_SEARCHING == state || MESH_TUNNEL3_NEW == state)
2669 GMT_change_state (connection->t, MESH_TUNNEL3_WAITING);
2670 if (MESH_CONNECTION_NEW == connection->state)
2671 connection_change_state (connection, MESH_CONNECTION_SENT);
2676 * Send a message to all peers in this connection that the connection
2677 * is no longer valid.
2679 * If some peer should not receive the message, it should be zero'ed out
2680 * before calling this function.
2682 * @param c The connection whose peers to notify.
2685 GMC_send_destroy (struct MeshConnection *c)
2687 struct GNUNET_MESH_ConnectionDestroy msg;
2689 if (GNUNET_YES == c->destroy)
2692 msg.header.size = htons (sizeof (msg));
2693 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY);;
2695 LOG (GNUNET_ERROR_TYPE_DEBUG,
2696 " sending connection destroy for connection %s\n",
2699 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_YES))
2700 GMC_send_prebuilt_message (&msg.header, c, GNUNET_YES, NULL, NULL);
2701 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_NO))
2702 GMC_send_prebuilt_message (&msg.header, c, GNUNET_NO, NULL, NULL);
2703 c->destroy = GNUNET_YES;
2704 c->state = MESH_CONNECTION_DESTROYED;
2709 * @brief Start a polling timer for the connection.
2711 * When a neighbor does not accept more traffic on the connection it could be
2712 * caused by a simple congestion or by a lost ACK. Polling enables to check
2713 * for the lastest ACK status for a connection.
2715 * @param c Connection.
2716 * @param fwd Should we poll in the FWD direction?
2719 GMC_start_poll (struct MeshConnection *c, int fwd)
2721 struct MeshFlowControl *fc;
2723 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2724 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL %s requested\n",
2725 fwd ? "FWD" : "BCK");
2726 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task || NULL != fc->poll_msg)
2728 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** not needed (%u, %p)\n",
2729 fc->poll_task, fc->poll_msg);
2732 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL started on request\n");
2733 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
2740 * @brief Stop polling a connection for ACKs.
2742 * Once we have enough ACKs for future traffic, polls are no longer necessary.
2744 * @param c Connection.
2745 * @param fwd Should we stop the poll in the FWD direction?
2748 GMC_stop_poll (struct MeshConnection *c, int fwd)
2750 struct MeshFlowControl *fc;
2752 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2753 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
2755 GNUNET_SCHEDULER_cancel (fc->poll_task);
2756 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2761 * Get a (static) string for a connection.
2763 * @param c Connection.
2766 GMC_2s (struct MeshConnection *c)
2770 static char buf[128];
2772 sprintf (buf, "%s (->%s)", GNUNET_h2s (&c->id), GMT_2s (c->t));
2775 return GNUNET_h2s (&c->id);