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_enc.h"
35 #include "gnunet-service-mesh_connection.h"
36 #include "gnunet-service-mesh_peer.h"
37 #include "gnunet-service-mesh_tunnel.h"
38 #include "gnunet-service-mesh_channel.h"
41 #define LOG(level, ...) GNUNET_log_from (level,"mesh-con",__VA_ARGS__)
43 #define MESH_MAX_POLL_TIME GNUNET_TIME_relative_multiply (\
44 GNUNET_TIME_UNIT_MINUTES,\
49 /******************************************************************************/
50 /******************************** STRUCTS **********************************/
51 /******************************************************************************/
54 * Struct to encapsulate all the Flow Control information to a peer to which
55 * we are directly connected (on a core level).
57 struct MeshFlowControl
60 * Connection this controls.
62 struct MeshConnection *c;
65 * How many messages are in the queue on this connection.
70 * How many messages do we accept in the queue.
72 unsigned int queue_max;
80 * ID of the last packet sent towards the peer.
82 uint32_t last_pid_sent;
85 * ID of the last packet received from the peer.
87 uint32_t last_pid_recv;
90 * Last ACK sent to the peer (peer can't send more than this PID).
92 uint32_t last_ack_sent;
95 * Last ACK sent towards the origin (for traffic towards leaf node).
97 uint32_t last_ack_recv;
100 * Task to poll the peer in case of a lost ACK causes stall.
102 GNUNET_SCHEDULER_TaskIdentifier poll_task;
105 * How frequently to poll for ACKs.
107 struct GNUNET_TIME_Relative poll_time;
111 * Keep a record of the last messages sent on this connection.
113 struct MeshConnectionPerformance
116 * Circular buffer for storing measurements.
118 double usecsperbyte[AVG_MSGS];
121 * Running average of @c usecsperbyte.
126 * How many values of @c usecsperbyte are valid.
131 * Index of the next "free" position in @c usecsperbyte.
138 * Struct containing all information regarding a connection to a peer.
140 struct MeshConnection
143 * Tunnel this connection is part of.
145 struct MeshTunnel3 *t;
148 * Flow control information for traffic fwd.
150 struct MeshFlowControl fwd_fc;
153 * Flow control information for traffic bck.
155 struct MeshFlowControl bck_fc;
158 * Measure connection performance on the endpoint.
160 struct MeshConnectionPerformance *perf;
163 * ID of the connection.
165 struct GNUNET_HashCode id;
168 * State of the connection.
170 enum MeshConnectionState state;
173 * Path being used for the tunnel.
175 struct MeshPeerPath *path;
178 * Position of the local peer in the path.
180 unsigned int own_pos;
183 * Task to keep the used paths alive at the owner,
184 * time tunnel out on all the other peers.
186 GNUNET_SCHEDULER_TaskIdentifier fwd_maintenance_task;
189 * Task to keep the used paths alive at the destination,
190 * time tunnel out on all the other peers.
192 GNUNET_SCHEDULER_TaskIdentifier bck_maintenance_task;
195 * Pending message count.
197 int pending_messages;
200 * Destroy flag: if true, destroy on last message.
205 /******************************************************************************/
206 /******************************* GLOBALS ***********************************/
207 /******************************************************************************/
210 * Global handle to the statistics service.
212 extern struct GNUNET_STATISTICS_Handle *stats;
215 * Local peer own ID (memory efficient handle).
217 extern GNUNET_PEER_Id myid;
220 * Local peer own ID (full value).
222 extern struct GNUNET_PeerIdentity my_full_id;
225 * Connections known, indexed by cid (MeshConnection).
227 static struct GNUNET_CONTAINER_MultiHashMap *connections;
230 * How many connections are we willing to maintain.
231 * Local connections are always allowed, even if there are more connections than max.
233 static unsigned long long max_connections;
236 * How many messages *in total* are we willing to queue, divide by number of
237 * connections to get connection queue size.
239 static unsigned long long max_msgs_queue;
242 * How often to send path keepalives. Paths timeout after 4 missed.
244 static struct GNUNET_TIME_Relative refresh_connection_time;
247 /******************************************************************************/
248 /******************************** STATIC ***********************************/
249 /******************************************************************************/
251 #if 0 // avoid compiler warning for unused static function
253 fc_debug (struct MeshFlowControl *fc)
255 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
256 fc->last_pid_recv, fc->last_ack_sent);
257 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
258 fc->last_pid_sent, fc->last_ack_recv);
259 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
260 fc->queue_n, fc->queue_max);
264 connection_debug (struct MeshConnection *c)
268 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CONNECTION ***\n");
271 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
272 peer2s (c->t->peer), GMC_2s (c));
273 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
274 c->state, c->pending_messages);
275 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
276 fc_debug (&c->fwd_fc);
277 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
278 fc_debug (&c->bck_fc);
283 * Get string description for tunnel state.
285 * @param s Tunnel state.
287 * @return String representation.
290 GMC_state2s (enum MeshConnectionState s)
294 case MESH_CONNECTION_NEW:
295 return "MESH_CONNECTION_NEW";
296 case MESH_CONNECTION_SENT:
297 return "MESH_CONNECTION_SENT";
298 case MESH_CONNECTION_ACK:
299 return "MESH_CONNECTION_ACK";
300 case MESH_CONNECTION_READY:
301 return "MESH_CONNECTION_READY";
303 return "MESH_CONNECTION_STATE_ERROR";
309 * Initialize a Flow Control structure to the initial state.
311 * @param fc Flow Control structure to initialize.
314 fc_init (struct MeshFlowControl *fc)
317 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
318 fc->last_pid_recv = (uint32_t) -1;
319 fc->last_ack_sent = (uint32_t) 0;
320 fc->last_ack_recv = (uint32_t) 0;
321 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
322 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
324 fc->queue_max = (max_msgs_queue / max_connections) + 1;
331 * @param cid Connection ID.
333 static struct MeshConnection *
334 connection_get (const struct GNUNET_HashCode *cid)
336 return GNUNET_CONTAINER_multihashmap_get (connections, cid);
341 connection_change_state (struct MeshConnection* c,
342 enum MeshConnectionState state)
344 LOG (GNUNET_ERROR_TYPE_DEBUG,
345 "Connection %s state was %s\n",
346 GMC_2s (c), GMC_state2s (c->state));
347 LOG (GNUNET_ERROR_TYPE_DEBUG,
348 "Connection %s state is now %s\n",
349 GMC_2s (c), GMC_state2s (state));
355 * Send an ACK on the connection, informing the predecessor about
356 * the available buffer space. Should not be called in case the peer
357 * is origin (no predecessor).
359 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
360 * the ACK itself goes "back" (dest->root).
362 * @param c Connection on which to send the ACK.
363 * @param buffer How much space free to advertise?
364 * @param fwd Is this FWD ACK? (Going dest->owner)
367 send_ack (struct MeshConnection *c, unsigned int buffer, int fwd)
369 struct MeshFlowControl *next_fc;
370 struct MeshFlowControl *prev_fc;
371 struct GNUNET_MESH_ACK msg;
375 /* If origin, there is no connection to send ACKs. Wrong function! */
376 if (GMC_is_origin (c, fwd))
382 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
383 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
385 LOG (GNUNET_ERROR_TYPE_DEBUG,
386 "connection send %s ack on %s\n",
387 fwd ? "FWD" : "BCK", GMC_2s (c));
389 /* Check if we need to transmit the ACK */
390 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
391 if (3 < delta && buffer < delta)
393 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
394 LOG (GNUNET_ERROR_TYPE_DEBUG,
395 " last pid recv: %u, last ack sent: %u\n",
396 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
400 /* Ok, ACK might be necessary, what PID to ACK? */
401 ack = prev_fc->last_pid_recv + buffer;
402 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
403 LOG (GNUNET_ERROR_TYPE_DEBUG,
404 " last pid %u, last ack %u, qmax %u, q %u\n",
405 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
406 next_fc->queue_max, next_fc->queue_n);
407 if (ack == prev_fc->last_ack_sent)
409 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
413 prev_fc->last_ack_sent = ack;
415 /* Build ACK message and send on connection */
416 msg.header.size = htons (sizeof (msg));
417 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ACK);
418 msg.ack = htonl (ack);
421 GMC_send_prebuilt_message (&msg.header, c, NULL, !fwd);
426 * Callback called when a queued message is sent.
428 * Calculates the average time and connection packet tracking.
430 * @param cls Closure.
431 * @param c Connection this message was on.
432 * @param type Type of message sent.
433 * @param fwd Was this a FWD going message?
434 * @param size Size of the message.
435 * @param wait Time spent waiting for core (only the time for THIS message)
438 message_sent (void *cls,
439 struct MeshConnection *c, uint16_t type,
440 int fwd, size_t size,
441 struct GNUNET_TIME_Relative wait)
443 struct MeshConnectionPerformance *p;
444 struct MeshFlowControl *fc;
447 fc = fwd ? &c->fwd_fc : &c->bck_fc;
448 LOG (GNUNET_ERROR_TYPE_DEBUG, "! sent %s\n", GNUNET_MESH_DEBUG_M2S (type));
449 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
450 c->pending_messages--;
451 if (GNUNET_YES == c->destroy && 0 == c->pending_messages)
453 LOG (GNUNET_ERROR_TYPE_DEBUG, "! destroying connection!\n");
456 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
459 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
462 LOG (GNUNET_ERROR_TYPE_DEBUG,
463 "! accounting pid %u\n",
465 GMC_send_ack (c, fwd);
470 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
473 return; /* Only endpoints are interested in timing. */
476 usecsperbyte = ((double) wait.rel_value_us) / size;
477 if (p->size == AVG_MSGS)
479 /* Array is full. Substract oldest value, add new one and store. */
480 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
481 p->usecsperbyte[p->idx] = usecsperbyte;
482 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
486 /* Array not yet full. Add current value to avg and store. */
487 p->usecsperbyte[p->idx] = usecsperbyte;
489 p->avg += p->usecsperbyte[p->idx];
493 p->idx = (p->idx + 1) % AVG_MSGS;
497 // c->t->pending_messages--;
498 // if (GNUNET_YES == c->t->destroy && 0 == t->pending_messages)
500 // LOG (GNUNET_ERROR_TYPE_DEBUG, "* destroying tunnel!\n");
501 // GMT_destroy (c->t);
508 * Get the previous hop in a connection
510 * @param c Connection.
512 * @return Previous peer in the connection.
514 static struct MeshPeer *
515 get_prev_hop (const struct MeshConnection *c)
519 if (0 == c->own_pos || c->path->length < 2)
520 id = c->path->peers[0];
522 id = c->path->peers[c->own_pos - 1];
524 return GMP_get_short (id);
529 * Get the next hop in a connection
531 * @param c Connection.
533 * @return Next peer in the connection.
535 static struct MeshPeer *
536 get_next_hop (const struct MeshConnection *c)
540 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
541 id = c->path->peers[c->path->length - 1];
543 id = c->path->peers[c->own_pos + 1];
545 return GMP_get_short (id);
550 * Get the hop in a connection.
552 * @param c Connection.
553 * @param fwd Next hop?
555 * @return Next peer in the connection.
557 static struct MeshPeer *
558 get_hop (struct MeshConnection *c, int fwd)
561 return get_next_hop (c);
562 return get_prev_hop (c);
567 * Is traffic coming from this sender 'FWD' traffic?
569 * @param c Connection to check.
570 * @param sender Peer identity of neighbor.
572 * @return GNUNET_YES in case the sender is the 'prev' hop and therefore
573 * the traffic is 'FWD'. GNUNET_NO for BCK. GNUNET_SYSERR for errors.
576 is_fwd (const struct MeshConnection *c,
577 const struct GNUNET_PeerIdentity *sender)
581 id = GNUNET_PEER_search (sender);
582 if (GMP_get_short_id (get_prev_hop (c)) == id)
585 if (GMP_get_short_id (get_next_hop (c)) == id)
589 return GNUNET_SYSERR;
594 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
595 * or a first CONNECTION_ACK directed to us.
597 * @param connection Connection to confirm.
598 * @param fwd Should we send it FWD?
599 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
602 send_connection_ack (struct MeshConnection *connection, int fwd)
604 struct MeshTunnel3 *t;
607 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection ack\n");
608 GMP_queue_add (get_hop (connection, fwd), NULL,
609 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK,
610 sizeof (struct GNUNET_MESH_ConnectionACK),
611 connection, NULL, fwd,
612 &message_sent, NULL);
613 if (MESH_TUNNEL3_NEW == GMT_get_state (t))
614 GMT_change_state (t, MESH_TUNNEL3_WAITING);
615 if (MESH_CONNECTION_READY != connection->state)
616 connection_change_state (connection, MESH_CONNECTION_SENT);
621 * Send a notification that a connection is broken.
623 * @param c Connection that is broken.
624 * @param id1 Peer that has disconnected.
625 * @param id2 Peer that has disconnected.
626 * @param fwd Direction towards which to send it.
629 send_broken (struct MeshConnection *c,
630 const struct GNUNET_PeerIdentity *id1,
631 const struct GNUNET_PeerIdentity *id2,
634 struct GNUNET_MESH_ConnectionBroken msg;
636 msg.header.size = htons (sizeof (struct GNUNET_MESH_ConnectionBroken));
637 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN);
641 GMC_send_prebuilt_message (&msg.header, c, NULL, fwd);
647 * Send keepalive packets for a connection.
649 * @param c Connection to keep alive..
650 * @param fwd Is this a FWD keepalive? (owner -> dest).
653 connection_keepalive (struct MeshConnection *c, int fwd)
655 struct GNUNET_MESH_ConnectionKeepAlive *msg;
656 size_t size = sizeof (struct GNUNET_MESH_ConnectionKeepAlive);
660 type = fwd ? GNUNET_MESSAGE_TYPE_MESH_FWD_KEEPALIVE :
661 GNUNET_MESSAGE_TYPE_MESH_BCK_KEEPALIVE;
663 LOG (GNUNET_ERROR_TYPE_DEBUG,
664 "sending %s keepalive for connection %s]\n",
665 fwd ? "FWD" : "BCK", GMC_2s (c));
667 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) cbuf;
668 msg->header.size = htons (size);
669 msg->header.type = htons (type);
672 GMC_send_prebuilt_message (&msg->header, c, NULL, fwd);
677 * Send CONNECTION_{CREATE/ACK} packets for a connection.
679 * @param c Connection for which to send the message.
680 * @param fwd If GNUNET_YES, send CREATE, otherwise send ACK.
683 connection_recreate (struct MeshConnection *c, int fwd)
685 LOG (GNUNET_ERROR_TYPE_DEBUG, "sending connection recreate\n");
689 send_connection_ack (c, GNUNET_NO);
694 * Generic connection timer management.
695 * Depending on the role of the peer in the connection will send the
696 * appropriate message (build or keepalive)
698 * @param c Conncetion to maintain.
702 connection_maintain (struct MeshConnection *c, int fwd)
704 if (MESH_TUNNEL3_SEARCHING == GMT_get_state (c->t))
706 /* TODO DHT GET with RO_BART */
711 case MESH_CONNECTION_NEW:
713 case MESH_CONNECTION_SENT:
714 connection_recreate (c, fwd);
716 case MESH_CONNECTION_READY:
717 connection_keepalive (c, fwd);
726 connection_fwd_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
728 struct MeshConnection *c = cls;
730 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
731 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
734 connection_maintain (c, GNUNET_YES);
735 c->fwd_maintenance_task = GNUNET_SCHEDULER_add_delayed (refresh_connection_time,
736 &connection_fwd_keepalive,
742 connection_bck_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
744 struct MeshConnection *c = cls;
746 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
747 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
750 connection_maintain (c, GNUNET_NO);
751 c->bck_maintenance_task = GNUNET_SCHEDULER_add_delayed (refresh_connection_time,
752 &connection_bck_keepalive,
758 * @brief Re-initiate traffic on this connection if necessary.
760 * Check if there is traffic queued towards this peer
761 * and the core transmit handle is NULL (traffic was stalled).
762 * If so, call core tmt rdy.
764 * @param c Connection on which initiate traffic.
765 * @param fwd Is this about fwd traffic?
768 connection_unlock_queue (struct MeshConnection *c, int fwd)
770 struct MeshPeer *peer;
772 LOG (GNUNET_ERROR_TYPE_DEBUG,
773 "connection_unlock_queue %s on %s\n",
774 fwd ? "FWD" : "BCK", GMC_2s (c));
776 if (GMC_is_terminal (c, fwd))
778 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal!\n");
782 peer = get_hop (c, fwd);
783 GMP_queue_unlock (peer, c);
788 * Cancel all transmissions that belong to a certain connection.
790 * @param c Connection which to cancel.
791 * @param fwd Cancel fwd traffic?
794 connection_cancel_queues (struct MeshConnection *c, int fwd)
797 struct MeshFlowControl *fc;
798 struct MeshPeer *peer;
806 peer = get_hop (c, fwd);
807 GMP_queue_cancel (peer, c);
809 fc = fwd ? &c->fwd_fc : &c->bck_fc;
810 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
812 GNUNET_SCHEDULER_cancel (fc->poll_task);
813 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
819 * Function called if a connection has been stalled for a while,
820 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
822 * @param cls Closure (poll ctx).
823 * @param tc TaskContext.
826 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
828 struct MeshFlowControl *fc = cls;
829 struct GNUNET_MESH_Poll msg;
830 struct MeshConnection *c;
832 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
833 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
839 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Polling!\n");
840 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** connection [%s]\n", GMC_2s (c));
841 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** %s\n",
842 fc == &c->fwd_fc ? "FWD" : "BCK");
844 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_POLL);
845 msg.header.size = htons (sizeof (msg));
846 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** pid (%u)!\n", fc->last_pid_sent);
847 GMC_send_prebuilt_message (&msg.header, c, NULL, fc == &c->fwd_fc);
848 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
849 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
850 &connection_poll, fc);
855 * Timeout function due to lack of keepalive/traffic from the owner.
856 * Destroys connection if called.
858 * @param cls Closure (connection to destroy).
859 * @param tc TaskContext.
862 connection_fwd_timeout (void *cls,
863 const struct GNUNET_SCHEDULER_TaskContext *tc)
865 struct MeshConnection *c = cls;
867 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
868 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
870 LOG (GNUNET_ERROR_TYPE_DEBUG,
871 "Connection %s[%X] FWD timed out. Destroying.\n",
875 if (GMC_is_origin (c, GNUNET_YES)) /* If local, leave. */
883 * Timeout function due to lack of keepalive/traffic from the destination.
884 * Destroys connection if called.
886 * @param cls Closure (connection to destroy).
887 * @param tc TaskContext
890 connection_bck_timeout (void *cls,
891 const struct GNUNET_SCHEDULER_TaskContext *tc)
893 struct MeshConnection *c = cls;
895 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
896 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
899 LOG (GNUNET_ERROR_TYPE_DEBUG,
900 "Connection %s[%X] FWD timed out. Destroying.\n",
901 GMT_2s (c->t), c->id);
903 if (GMC_is_origin (c, GNUNET_NO)) /* If local, leave. */
911 * Resets the connection timeout task, some other message has done the
913 * - For the first peer on the direction this means to send
914 * a keepalive or a path confirmation message (either create or ACK).
915 * - For all other peers, this means to destroy the connection,
916 * due to lack of activity.
917 * Starts the tiemout if no timeout was running (connection just created).
919 * @param c Connection whose timeout to reset.
920 * @param fwd Is this forward?
922 * TODO use heap to improve efficiency of scheduler.
925 connection_reset_timeout (struct MeshConnection *c, int fwd)
927 GNUNET_SCHEDULER_TaskIdentifier *ti;
928 GNUNET_SCHEDULER_Task f;
930 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
932 if (GNUNET_SCHEDULER_NO_TASK != *ti)
933 GNUNET_SCHEDULER_cancel (*ti);
935 if (GMC_is_origin (c, fwd)) /* Endpoint */
937 f = fwd ? &connection_fwd_keepalive : &connection_bck_keepalive;
938 *ti = GNUNET_SCHEDULER_add_delayed (refresh_connection_time, f, c);
942 struct GNUNET_TIME_Relative delay;
944 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
945 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
946 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
952 * Add the connection to the list of both neighbors.
954 * @param c Connection.
957 register_neighbors (struct MeshConnection *c)
959 struct MeshPeer *peer;
961 peer = get_next_hop (c);
962 if (GNUNET_NO == GMP_is_neighbor (peer))
967 GMP_add_connection (peer, c);
968 peer = get_prev_hop (c);
969 if (GNUNET_NO == GMP_is_neighbor (peer))
974 GMP_add_connection (peer, c);
979 * Remove the connection from the list of both neighbors.
981 * @param c Connection.
984 unregister_neighbors (struct MeshConnection *c)
986 struct MeshPeer *peer;
988 peer = get_next_hop (c);
989 GMP_remove_connection (peer, c);
991 peer = get_prev_hop (c);
992 GMP_remove_connection (peer, c);
998 * Bind the connection to the peer and the tunnel to that peer.
1000 * If the peer has no tunnel, create one. Update tunnel and connection
1001 * data structres to reflect new status.
1003 * @param c Connection.
1007 add_to_peer (struct MeshConnection *c, struct MeshPeer *peer)
1009 GMP_add_tunnel (peer);
1010 c->t = GMP_get_tunnel (peer);
1011 GMT_add_connection (c->t, c);
1014 /******************************************************************************/
1015 /******************************** API ***********************************/
1016 /******************************************************************************/
1019 * Core handler for connection creation.
1021 * @param cls Closure (unused).
1022 * @param peer Sender (neighbor).
1023 * @param message Message.
1025 * @return GNUNET_OK to keep the connection open,
1026 * GNUNET_SYSERR to close it (signal serious error)
1029 GMC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
1030 const struct GNUNET_MessageHeader *message)
1032 struct GNUNET_MESH_ConnectionCreate *msg;
1033 struct GNUNET_PeerIdentity *id;
1034 struct GNUNET_HashCode *cid;
1035 struct MeshPeerPath *path;
1036 struct MeshPeer *dest_peer;
1037 struct MeshPeer *orig_peer;
1038 struct MeshConnection *c;
1039 unsigned int own_pos;
1043 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1044 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection create msg\n");
1047 size = ntohs (message->size);
1048 if (size < sizeof (struct GNUNET_MESH_ConnectionCreate))
1050 GNUNET_break_op (0);
1054 /* Calculate hops */
1055 size -= sizeof (struct GNUNET_MESH_ConnectionCreate);
1056 if (size % sizeof (struct GNUNET_PeerIdentity))
1058 GNUNET_break_op (0);
1061 size /= sizeof (struct GNUNET_PeerIdentity);
1064 GNUNET_break_op (0);
1067 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1069 /* Get parameters */
1070 msg = (struct GNUNET_MESH_ConnectionCreate *) message;
1072 id = (struct GNUNET_PeerIdentity *) &msg[1];
1073 LOG (GNUNET_ERROR_TYPE_DEBUG,
1074 " connection %s (%s).\n",
1075 GNUNET_h2s (cid), GNUNET_i2s (id));
1077 /* Create connection */
1078 c = connection_get (cid);
1082 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating path...\n");
1083 path = path_new (size);
1085 for (i = 0; i < size; i++)
1087 LOG (GNUNET_ERROR_TYPE_DEBUG, " ... adding %s\n",
1088 GNUNET_i2s (&id[i]));
1089 path->peers[i] = GNUNET_PEER_intern (&id[i]);
1090 if (path->peers[i] == myid)
1093 if (own_pos == 0 && path->peers[own_pos] != myid)
1095 /* create path: self not found in path through self */
1096 GNUNET_break_op (0);
1097 path_destroy (path);
1100 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1101 GMP_add_path_to_all (path, GNUNET_NO);
1102 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1103 c = GMC_new (cid, NULL, path_duplicate (path), own_pos);
1106 connection_reset_timeout (c, GNUNET_YES);
1112 if (MESH_CONNECTION_NEW == c->state)
1113 connection_change_state (c, MESH_CONNECTION_SENT);
1115 /* Remember peers */
1116 dest_peer = GMP_get (&id[size - 1]);
1117 orig_peer = GMP_get (&id[0]);
1119 /* Is it a connection to us? */
1120 if (c->own_pos == size - 1)
1122 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1123 GMP_add_path_to_origin (orig_peer, path, GNUNET_YES);
1125 add_to_peer (c, orig_peer);
1126 if (MESH_TUNNEL3_NEW == GMT_get_state (c->t))
1127 GMT_change_state (c->t, MESH_TUNNEL3_WAITING);
1129 send_connection_ack (c, GNUNET_NO);
1130 if (MESH_CONNECTION_SENT == c->state)
1131 connection_change_state (c, MESH_CONNECTION_ACK);
1133 /* Keep tunnel alive in direction dest->owner*/
1134 connection_reset_timeout (c, GNUNET_NO);
1138 /* It's for somebody else! Retransmit. */
1139 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
1140 GMP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1141 GMP_add_path_to_origin (orig_peer, path, GNUNET_NO);
1142 GMC_send_prebuilt_message (message, c, NULL, GNUNET_YES);
1149 * Core handler for path confirmations.
1151 * @param cls closure
1152 * @param message message
1153 * @param peer peer identity this notification is about
1155 * @return GNUNET_OK to keep the connection open,
1156 * GNUNET_SYSERR to close it (signal serious error)
1159 GMC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
1160 const struct GNUNET_MessageHeader *message)
1162 struct GNUNET_MESH_ConnectionACK *msg;
1163 struct MeshConnection *c;
1164 struct MeshPeerPath *p;
1165 struct MeshPeer *pi;
1168 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1169 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection ACK msg\n");
1170 msg = (struct GNUNET_MESH_ConnectionACK *) message;
1171 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n",
1172 GNUNET_h2s (&msg->cid));
1173 c = connection_get (&msg->cid);
1176 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1178 LOG (GNUNET_ERROR_TYPE_DEBUG, " don't know the connection!\n");
1183 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n",
1185 pi = GMP_get (peer);
1186 if (get_next_hop (c) == pi)
1188 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
1190 if (MESH_CONNECTION_SENT == c->state)
1191 connection_change_state (c, MESH_CONNECTION_ACK);
1193 else if (get_prev_hop (c) == pi)
1195 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK\n");
1197 connection_change_state (c, MESH_CONNECTION_READY);
1201 GNUNET_break_op (0);
1204 connection_reset_timeout (c, fwd);
1206 /* Add path to peers? */
1210 GMP_add_path_to_all (p, GNUNET_YES);
1217 /* Message for us as creator? */
1218 if (GMC_is_origin (c, GNUNET_YES))
1220 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
1221 connection_change_state (c, MESH_CONNECTION_READY);
1222 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1223 send_connection_ack (c, GNUNET_YES);
1224 GMT_send_queued_data (c->t, GNUNET_YES);
1228 /* Message for us as destination? */
1229 if (GMC_is_terminal (c, GNUNET_YES))
1231 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
1232 connection_change_state (c, MESH_CONNECTION_READY);
1233 GMT_change_state (c->t, MESH_TUNNEL3_READY);
1234 GMT_send_queued_data (c->t, GNUNET_NO);
1238 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1239 GMC_send_prebuilt_message (message, c, NULL, fwd);
1245 * Core handler for notifications of broken paths
1247 * @param cls Closure (unused).
1248 * @param id Peer identity of sending neighbor.
1249 * @param message Message.
1251 * @return GNUNET_OK to keep the connection open,
1252 * GNUNET_SYSERR to close it (signal serious error)
1255 GMC_handle_broken (void* cls,
1256 const struct GNUNET_PeerIdentity* id,
1257 const struct GNUNET_MessageHeader* message)
1259 struct GNUNET_MESH_ConnectionBroken *msg;
1260 struct MeshConnection *c;
1263 LOG (GNUNET_ERROR_TYPE_DEBUG,
1264 "Received a CONNECTION BROKEN msg from %s\n", GNUNET_i2s (id));
1265 msg = (struct GNUNET_MESH_ConnectionBroken *) message;
1266 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1267 GNUNET_i2s (&msg->peer1));
1268 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1269 GNUNET_i2s (&msg->peer2));
1270 c = connection_get (&msg->cid);
1273 GNUNET_break_op (0);
1277 fwd = is_fwd (c, id);
1278 connection_cancel_queues (c, !fwd);
1279 if (GMC_is_terminal (c, fwd))
1281 if (0 < c->pending_messages)
1282 c->destroy = GNUNET_YES;
1288 GMC_send_prebuilt_message (message, c, NULL, fwd);
1289 c->destroy = GNUNET_YES;
1298 * Core handler for tunnel destruction
1300 * @param cls Closure (unused).
1301 * @param peer Peer identity of sending neighbor.
1302 * @param message Message.
1304 * @return GNUNET_OK to keep the connection open,
1305 * GNUNET_SYSERR to close it (signal serious error)
1308 GMC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
1309 const struct GNUNET_MessageHeader *message)
1311 struct GNUNET_MESH_ConnectionDestroy *msg;
1312 struct MeshConnection *c;
1315 msg = (struct GNUNET_MESH_ConnectionDestroy *) message;
1316 LOG (GNUNET_ERROR_TYPE_DEBUG,
1317 "Got a CONNECTION DESTROY message from %s\n",
1319 LOG (GNUNET_ERROR_TYPE_DEBUG,
1320 " for connection %s\n",
1321 GNUNET_h2s (&msg->cid));
1322 c = connection_get (&msg->cid);
1325 /* Probably already got the message from another path,
1326 * destroyed the tunnel and retransmitted to children.
1329 GNUNET_STATISTICS_update (stats, "# control on unknown tunnel",
1333 fwd = is_fwd (c, peer);
1334 if (GNUNET_SYSERR == fwd)
1336 GNUNET_break_op (0);
1339 GMC_send_prebuilt_message (message, c, NULL, fwd);
1340 c->destroy = GNUNET_YES;
1346 * Generic handler for mesh network encrypted traffic.
1348 * @param peer Peer identity this notification is about.
1349 * @param message Encrypted message.
1351 * @return GNUNET_OK to keep the connection open,
1352 * GNUNET_SYSERR to close it (signal serious error)
1355 handle_mesh_encrypted (const struct GNUNET_PeerIdentity *peer,
1356 const struct GNUNET_MESH_Encrypted *msg)
1358 struct MeshConnection *c;
1359 struct MeshPeer *neighbor;
1360 struct MeshFlowControl *fc;
1361 GNUNET_PEER_Id peer_id;
1369 size = ntohs (msg->header.size);
1371 sizeof (struct GNUNET_MESH_Encrypted) +
1372 sizeof (struct GNUNET_MessageHeader))
1374 GNUNET_break_op (0);
1377 type = ntohs (msg->header.type);
1378 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1379 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message from %s\n",
1380 GNUNET_MESH_DEBUG_M2S (type), GNUNET_i2s (peer));
1382 /* Check connection */
1383 c = connection_get (&msg->cid);
1386 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1387 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING connection unknown\n");
1391 /* Check if origin is as expected */
1392 neighbor = get_prev_hop (c);
1393 peer_id = GNUNET_PEER_search (peer);
1394 if (peer_id == GMP_get_short_id (neighbor))
1400 neighbor = get_next_hop (c);
1401 if (peer_id == GMP_get_short_id (neighbor))
1407 GNUNET_break_op (0);
1411 fc = fwd ? &c->bck_fc : &c->fwd_fc;
1414 pid = ntohl (msg->pid);
1415 if (GMC_is_pid_bigger (pid, fc->last_ack_sent))
1417 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
1418 LOG (GNUNET_ERROR_TYPE_DEBUG,
1419 "WARNING Received PID %u, (prev %u), ACK %u\n",
1420 pid, fc->last_pid_recv, fc->last_ack_sent);
1423 if (GNUNET_NO == GMC_is_pid_bigger (pid, fc->last_pid_recv))
1425 GNUNET_STATISTICS_update (stats, "# duplicate PID", 1, GNUNET_NO);
1426 LOG (GNUNET_ERROR_TYPE_DEBUG,
1427 " Pid %u not expected (%u+), dropping!\n",
1428 pid, fc->last_pid_recv + 1);
1431 if (MESH_CONNECTION_SENT == c->state)
1432 connection_change_state (c, MESH_CONNECTION_READY);
1433 connection_reset_timeout (c, fwd);
1434 fc->last_pid_recv = pid;
1436 /* Is this message for us? */
1437 if (GMC_is_terminal (c, fwd))
1439 /* TODO signature verification */
1440 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1441 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1448 fc->last_pid_recv = pid;
1449 GMT_handle_encrypted (c->t, msg, fwd);
1450 GMC_send_ack (c, fwd);
1454 /* Message not for us: forward to next hop */
1455 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1456 ttl = ntohl (msg->ttl);
1457 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
1460 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
1461 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
1462 GMC_send_ack (c, fwd);
1465 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1467 GMC_send_prebuilt_message (&msg->header, c, NULL, fwd);
1474 * Core handler for encrypted mesh network traffic (channel mgmt, data).
1476 * @param cls Closure (unused).
1477 * @param message Message received.
1478 * @param peer Peer who sent the message.
1480 * @return GNUNET_OK to keep the connection open,
1481 * GNUNET_SYSERR to close it (signal serious error)
1484 GMC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
1485 const struct GNUNET_MessageHeader *message)
1487 return handle_mesh_encrypted (peer,
1488 (struct GNUNET_MESH_Encrypted *)message);
1493 * Core handler for mesh network traffic point-to-point acks.
1495 * @param cls closure
1496 * @param message message
1497 * @param peer peer identity this notification is about
1499 * @return GNUNET_OK to keep the connection open,
1500 * GNUNET_SYSERR to close it (signal serious error)
1503 GMC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
1504 const struct GNUNET_MessageHeader *message)
1506 struct GNUNET_MESH_ACK *msg;
1507 struct MeshConnection *c;
1508 struct MeshFlowControl *fc;
1513 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1514 LOG (GNUNET_ERROR_TYPE_DEBUG, "Got an ACK packet from %s!\n",
1516 msg = (struct GNUNET_MESH_ACK *) message;
1518 c = connection_get (&msg->cid);
1522 GNUNET_STATISTICS_update (stats, "# ack on unknown connection", 1,
1527 /* Is this a forward or backward ACK? */
1528 id = GNUNET_PEER_search (peer);
1529 if (GMP_get_short_id (get_next_hop (c)) == id)
1531 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
1535 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1537 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
1543 GNUNET_break_op (0);
1547 ack = ntohl (msg->ack);
1548 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u (was %u)\n",
1549 ack, fc->last_ack_recv);
1550 if (GMC_is_pid_bigger (ack, fc->last_ack_recv))
1551 fc->last_ack_recv = ack;
1553 /* Cancel polling if the ACK is big enough. */
1554 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task &&
1555 GMC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
1557 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
1558 GNUNET_SCHEDULER_cancel (fc->poll_task);
1559 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1560 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
1563 connection_unlock_queue (c, fwd);
1570 * Core handler for mesh network traffic point-to-point ack polls.
1572 * @param cls closure
1573 * @param message message
1574 * @param peer peer identity this notification is about
1576 * @return GNUNET_OK to keep the connection open,
1577 * GNUNET_SYSERR to close it (signal serious error)
1580 GMC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
1581 const struct GNUNET_MessageHeader *message)
1583 struct GNUNET_MESH_Poll *msg;
1584 struct MeshConnection *c;
1585 struct MeshFlowControl *fc;
1590 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1591 LOG (GNUNET_ERROR_TYPE_DEBUG, "Got a POLL packet from %s!\n",
1594 msg = (struct GNUNET_MESH_Poll *) message;
1596 c = connection_get (&msg->cid);
1600 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
1602 GNUNET_break_op (0);
1606 /* Is this a forward or backward ACK?
1607 * Note: a poll should never be needed in a loopback case,
1608 * since there is no possiblility of packet loss there, so
1609 * this way of discerining FWD/BCK should not be a problem.
1611 id = GNUNET_PEER_search (peer);
1612 if (GMP_get_short_id (get_next_hop (c)) == id)
1614 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
1617 else if (GMP_get_short_id (get_prev_hop (c)) == id)
1619 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
1624 GNUNET_break_op (0);
1628 pid = ntohl (msg->pid);
1629 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n",
1630 pid, fc->last_pid_recv);
1631 fc->last_pid_recv = pid;
1632 fwd = fc == &c->fwd_fc;
1633 GMC_send_ack (c, fwd);
1640 * Core handler for mesh keepalives.
1642 * @param cls closure
1643 * @param message message
1644 * @param peer peer identity this notification is about
1645 * @return GNUNET_OK to keep the connection open,
1646 * GNUNET_SYSERR to close it (signal serious error)
1648 * TODO: Check who we got this from, to validate route.
1651 GMC_handle_keepalive (void *cls, const struct GNUNET_PeerIdentity *peer,
1652 const struct GNUNET_MessageHeader *message)
1654 struct GNUNET_MESH_ConnectionKeepAlive *msg;
1655 struct MeshConnection *c;
1656 struct MeshPeer *neighbor;
1659 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) message;
1660 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a keepalive packet from %s\n",
1663 c = connection_get (&msg->cid);
1666 GNUNET_STATISTICS_update (stats, "# keepalive on unknown connection", 1,
1671 fwd = GNUNET_MESSAGE_TYPE_MESH_FWD_KEEPALIVE == ntohs (message->type) ?
1672 GNUNET_YES : GNUNET_NO;
1674 /* Check if origin is as expected */
1675 neighbor = get_hop (c, fwd);
1676 if (GNUNET_PEER_search (peer) != GMP_get_short_id (neighbor))
1678 GNUNET_break_op (0);
1682 connection_change_state (c, MESH_CONNECTION_READY);
1683 connection_reset_timeout (c, fwd);
1685 if (GMC_is_terminal (c, fwd))
1688 GNUNET_STATISTICS_update (stats, "# keepalives forwarded", 1, GNUNET_NO);
1689 GMC_send_prebuilt_message (message, c, NULL, fwd);
1696 * Send an ACK on the appropriate connection/channel, depending on
1697 * the direction and the position of the peer.
1699 * @param c Which connection to send the hop-by-hop ACK.
1700 * @param fwd Is this a fwd ACK? (will go dest->root)
1703 GMC_send_ack (struct MeshConnection *c, int fwd)
1705 unsigned int buffer;
1707 LOG (GNUNET_ERROR_TYPE_DEBUG,
1708 "GMC send %s ACK on %s\n",
1709 fwd ? "FWD" : "BCK", GMC_2s (c));
1717 /* Get available buffer space */
1718 if (GMC_is_terminal (c, fwd))
1720 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
1721 buffer = GMT_get_buffer (c->t, fwd);
1725 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
1726 buffer = GMC_get_buffer (c, fwd);
1728 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
1730 /* Send available buffer space */
1731 if (GMC_is_origin (c, fwd))
1733 GNUNET_assert (NULL != c->t);
1734 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
1737 LOG (GNUNET_ERROR_TYPE_DEBUG, " really sending!\n");
1738 GMT_unchoke_channels (c->t, fwd);
1743 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
1744 send_ack (c, buffer, fwd);
1750 * Initialize the connections subsystem
1752 * @param c Configuration handle.
1755 GMC_init (const struct GNUNET_CONFIGURATION_Handle *c)
1757 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
1759 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_MSGS_QUEUE",
1762 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
1763 "MESH", "MAX_MSGS_QUEUE", "MISSING");
1764 GNUNET_SCHEDULER_shutdown ();
1769 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_CONNECTIONS",
1772 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
1773 "MESH", "MAX_CONNECTIONS", "MISSING");
1774 GNUNET_SCHEDULER_shutdown ();
1779 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REFRESH_CONNECTION_TIME",
1780 &refresh_connection_time))
1782 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
1783 "MESH", "REFRESH_CONNECTION_TIME", "MISSING");
1784 GNUNET_SCHEDULER_shutdown ();
1787 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_YES);
1791 * Shut down the connections subsystem.
1796 GNUNET_CONTAINER_multihashmap_destroy (connections);
1800 struct MeshConnection *
1801 GMC_new (const struct GNUNET_HashCode *cid,
1802 struct MeshTunnel3 *t,
1803 struct MeshPeerPath *p,
1804 unsigned int own_pos)
1806 struct MeshConnection *c;
1808 c = GNUNET_new (struct MeshConnection);
1810 GNUNET_CONTAINER_multihashmap_put (connections, &c->id, c,
1811 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST);
1812 fc_init (&c->fwd_fc);
1813 fc_init (&c->bck_fc);
1818 if (own_pos > p->length - 1)
1824 c->own_pos = own_pos;
1829 c->fwd_maintenance_task =
1830 GNUNET_SCHEDULER_add_delayed (refresh_connection_time,
1831 &connection_fwd_keepalive, c);
1833 register_neighbors (c);
1839 GMC_destroy (struct MeshConnection *c)
1844 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying connection %s\n", GMC_2s (c));
1846 /* Cancel all traffic */
1847 connection_cancel_queues (c, GNUNET_YES);
1848 connection_cancel_queues (c, GNUNET_NO);
1850 /* Cancel maintainance task (keepalive/timeout) */
1851 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_maintenance_task)
1852 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
1853 if (GNUNET_SCHEDULER_NO_TASK != c->bck_maintenance_task)
1854 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
1856 /* Unregister from neighbors */
1857 unregister_neighbors (c);
1860 GNUNET_STATISTICS_update (stats, "# connections", -1, GNUNET_NO);
1862 GMT_remove_connection (c->t, c);
1867 * Get the connection ID.
1869 * @param c Connection to get the ID from.
1871 * @return ID of the connection.
1873 const struct GNUNET_HashCode *
1874 GMC_get_id (const struct MeshConnection *c)
1881 * Get the connection path.
1883 * @param c Connection to get the path from.
1885 * @return path used by the connection.
1887 const struct MeshPeerPath *
1888 GMC_get_path (const struct MeshConnection *c)
1895 * Get the connection state.
1897 * @param c Connection to get the state from.
1899 * @return state of the connection.
1901 enum MeshConnectionState
1902 GMC_get_state (const struct MeshConnection *c)
1908 * Get the connection tunnel.
1910 * @param c Connection to get the tunnel from.
1912 * @return tunnel of the connection.
1914 struct MeshTunnel3 *
1915 GMC_get_tunnel (const struct MeshConnection *c)
1922 * Get free buffer space in a connection.
1924 * @param c Connection.
1925 * @param fwd Is query about FWD traffic?
1927 * @return Free buffer space [0 - max_msgs_queue/max_connections]
1930 GMC_get_buffer (struct MeshConnection *c, int fwd)
1932 struct MeshFlowControl *fc;
1934 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1936 return (fc->queue_max - fc->queue_n);
1940 * Get how many messages have we allowed to send to us from a direction..
1942 * @param c Connection.
1943 * @param fwd Are we asking about traffic from FWD (BCK messages)?
1945 * @return last_ack_sent - last_pid_recv
1948 GMC_get_allowed (struct MeshConnection *c, int fwd)
1950 struct MeshFlowControl *fc;
1952 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1953 if (GMC_is_pid_bigger(fc->last_pid_recv, fc->last_ack_sent))
1957 return (fc->last_ack_sent - fc->last_pid_recv);
1961 * Get messages queued in a connection.
1963 * @param c Connection.
1964 * @param fwd Is query about FWD traffic?
1966 * @return Number of messages queued.
1969 GMC_get_qn (struct MeshConnection *c, int fwd)
1971 struct MeshFlowControl *fc;
1973 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1980 * Allow the connection to advertise a buffer of the given size.
1982 * The connection will send an @c fwd ACK message (so: in direction !fwd)
1983 * allowing up to last_pid_recv + buffer.
1985 * @param c Connection.
1986 * @param buffer How many more messages the connection can accept.
1987 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
1990 GMC_allow (struct MeshConnection *c, unsigned int buffer, int fwd)
1992 send_ack (c, buffer, fwd);
1997 * Notify other peers on a connection of a broken link. Mark connections
1998 * to destroy after all traffic has been sent.
2000 * @param c Connection on which there has been a disconnection.
2001 * @param peer Peer that disconnected.
2004 GMC_notify_broken (struct MeshConnection *c,
2005 struct MeshPeer *peer)
2009 fwd = peer == get_prev_hop (c);
2011 connection_cancel_queues (c, !fwd);
2012 if (GMC_is_terminal (c, fwd))
2014 /* Local shutdown, no one to notify about this. */
2019 send_broken (c, &my_full_id, GMP_get_id (peer), fwd);
2021 /* Connection will have at least one pending message
2022 * (the one we just scheduled), so no point in checking whether to
2023 * destroy immediately. */
2024 c->destroy = GNUNET_YES;
2031 * Is this peer the first one on the connection?
2033 * @param c Connection.
2034 * @param fwd Is this about fwd traffic?
2036 * @return GNUNET_YES if origin, GNUNET_NO if relay/terminal.
2039 GMC_is_origin (struct MeshConnection *c, int fwd)
2041 if (!fwd && c->path->length - 1 == c->own_pos )
2043 if (fwd && 0 == c->own_pos)
2050 * Is this peer the last one on the connection?
2052 * @param c Connection.
2053 * @param fwd Is this about fwd traffic?
2054 * Note that the ROOT is the terminal for BCK traffic!
2056 * @return GNUNET_YES if terminal, GNUNET_NO if relay/origin.
2059 GMC_is_terminal (struct MeshConnection *c, int fwd)
2061 return GMC_is_origin (c, !fwd);
2066 * See if we are allowed to send by the next hop in the given direction.
2068 * @param c Connection.
2069 * @param fwd Is this about fwd traffic?
2071 * @return GNUNET_YES in case it's OK.
2074 GMC_is_sendable (struct MeshConnection *c, int fwd)
2076 struct MeshFlowControl *fc;
2078 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2079 if (GMC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2085 * Sends an already built message on a connection, properly registering
2086 * all used resources.
2088 * @param message Message to send. Function makes a copy of it.
2089 * If message is not hop-by-hop, decrements TTL of copy.
2090 * @param c Connection on which this message is transmitted.
2091 * @param ch Channel on which this message is transmitted, or NULL.
2092 * @param fwd Is this a fwd message?
2095 GMC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2096 struct MeshConnection *c,
2097 struct MeshChannel *ch,
2100 struct MeshFlowControl *fc;
2106 size = ntohs (message->size);
2107 data = GNUNET_malloc (size);
2108 memcpy (data, message, size);
2109 type = ntohs (message->type);
2110 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send %s (%u) on connection %s\n",
2111 GNUNET_MESH_DEBUG_M2S (type), size, GMC_2s (c));
2113 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2114 droppable = GNUNET_YES;
2117 struct GNUNET_MESH_Encrypted *emsg;
2118 struct GNUNET_MESH_ACK *amsg;
2119 struct GNUNET_MESH_Poll *pmsg;
2120 struct GNUNET_MESH_ConnectionDestroy *dmsg;
2121 struct GNUNET_MESH_ConnectionBroken *bmsg;
2124 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
2125 emsg = (struct GNUNET_MESH_Encrypted *) data;
2126 ttl = ntohl (emsg->ttl);
2129 GNUNET_break_op (0);
2133 emsg->ttl = htonl (ttl - 1);
2134 emsg->pid = htonl (fwd ? c->fwd_fc.next_pid++ : c->bck_fc.next_pid++);
2135 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
2137 LOG (GNUNET_ERROR_TYPE_DEBUG, "pid %u\n", ntohl (emsg->pid));
2138 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid %u\n", fc->last_pid_sent);
2139 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", fc->last_ack_recv);
2140 if (GMC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
2142 GMC_start_poll (c, fwd);
2146 case GNUNET_MESSAGE_TYPE_MESH_ACK:
2147 amsg = (struct GNUNET_MESH_ACK *) data;
2149 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
2150 droppable = GNUNET_NO;
2153 case GNUNET_MESSAGE_TYPE_MESH_POLL:
2154 pmsg = (struct GNUNET_MESH_Poll *) data;
2156 pmsg->pid = htonl (fwd ? c->fwd_fc.last_pid_sent : c->bck_fc.last_pid_sent);
2157 LOG (GNUNET_ERROR_TYPE_DEBUG, " poll %u\n", ntohl (pmsg->pid));
2158 droppable = GNUNET_NO;
2161 case GNUNET_MESSAGE_TYPE_MESH_TUNNEL_DESTROY:
2162 dmsg = (struct GNUNET_MESH_ConnectionDestroy *) data;
2167 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN:
2168 bmsg = (struct GNUNET_MESH_ConnectionBroken *) data;
2173 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE:
2174 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK:
2181 if (fc->queue_n >= fc->queue_max && droppable)
2183 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
2186 LOG (GNUNET_ERROR_TYPE_DEBUG,
2187 "queue full: %u/%u\n",
2188 fc->queue_n, fc->queue_max);
2189 return; /* Drop this message */
2192 c->pending_messages++;
2194 GMP_queue_add (get_hop (c, fwd), data, type, size, c, ch, fwd,
2195 &message_sent, NULL);
2200 * Sends a CREATE CONNECTION message for a path to a peer.
2201 * Changes the connection and tunnel states if necessary.
2203 * @param connection Connection to create.
2206 GMC_send_create (struct MeshConnection *connection)
2208 enum MeshTunnel3State state;
2211 size = sizeof (struct GNUNET_MESH_ConnectionCreate);
2212 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
2213 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection create\n");
2214 GMP_queue_add (get_next_hop (connection), NULL,
2215 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE,
2216 size, connection, NULL,
2217 GNUNET_YES, &message_sent, NULL);
2218 state = GMT_get_state (connection->t);
2219 if (MESH_TUNNEL3_SEARCHING == state || MESH_TUNNEL3_NEW == state)
2220 GMT_change_state (connection->t, MESH_TUNNEL3_WAITING);
2221 if (MESH_CONNECTION_NEW == connection->state)
2222 connection_change_state (connection, MESH_CONNECTION_SENT);
2227 * Send a message to all peers in this connection that the connection
2228 * is no longer valid.
2230 * If some peer should not receive the message, it should be zero'ed out
2231 * before calling this function.
2233 * @param c The connection whose peers to notify.
2236 GMC_send_destroy (struct MeshConnection *c)
2238 struct GNUNET_MESH_ConnectionDestroy msg;
2240 if (GNUNET_YES == c->destroy)
2243 msg.header.size = htons (sizeof (msg));
2244 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_TUNNEL_DESTROY);;
2246 LOG (GNUNET_ERROR_TYPE_DEBUG,
2247 " sending connection destroy for connection %s\n",
2250 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_YES))
2251 GMC_send_prebuilt_message (&msg.header, c, NULL, GNUNET_YES);
2252 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_NO))
2253 GMC_send_prebuilt_message (&msg.header, c, NULL, GNUNET_NO);
2254 c->destroy = GNUNET_YES;
2259 * @brief Start a polling timer for the connection.
2261 * When a neighbor does not accept more traffic on the connection it could be
2262 * caused by a simple congestion or by a lost ACK. Polling enables to check
2263 * for the lastest ACK status for a connection.
2265 * @param c Connection.
2266 * @param fwd Should we poll in the FWD direction?
2269 GMC_start_poll (struct MeshConnection *c, int fwd)
2271 struct MeshFlowControl *fc;
2273 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2274 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
2278 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
2285 * @brief Stop polling a connection for ACKs.
2287 * Once we have enough ACKs for future traffic, polls are no longer necessary.
2289 * @param c Connection.
2290 * @param fwd Should we stop the poll in the FWD direction?
2293 GMC_stop_poll (struct MeshConnection *c, int fwd)
2295 struct MeshFlowControl *fc;
2297 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2298 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
2300 GNUNET_SCHEDULER_cancel (fc->poll_task);
2301 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2306 * Get a (static) string for a connection.
2308 * @param c Connection.
2311 GMC_2s (struct MeshConnection *c)
2315 static char buf[128];
2317 sprintf (buf, "%s (->%s)", GNUNET_h2s (&c->id), GMT_2s (c->t));
2320 return GNUNET_h2s (&c->id);