2 This file is part of GNUnet.
3 (C) 2001-2013 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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22 * @file mesh/gnunet-service-mesh_connection.c
23 * @brief GNUnet MESH service connection handling
24 * @author Bartlomiej Polot
28 #include "gnunet_util_lib.h"
30 #include "gnunet_statistics_service.h"
32 #include "mesh_path.h"
33 #include "mesh_protocol.h"
35 #include "gnunet-service-mesh_connection.h"
36 #include "gnunet-service-mesh_peer.h"
37 #include "gnunet-service-mesh_tunnel.h"
40 #define LOG(level, ...) GNUNET_log_from (level,"mesh-con",__VA_ARGS__)
42 #define MESH_MAX_POLL_TIME GNUNET_TIME_relative_multiply (\
43 GNUNET_TIME_UNIT_MINUTES,\
48 /******************************************************************************/
49 /******************************** STRUCTS **********************************/
50 /******************************************************************************/
53 * Struct to encapsulate all the Flow Control information to a peer to which
54 * we are directly connected (on a core level).
56 struct MeshFlowControl
59 * Connection this controls.
61 struct MeshConnection *c;
64 * How many messages are in the queue on this connection.
69 * How many messages do we accept in the queue.
71 unsigned int queue_max;
79 * ID of the last packet sent towards the peer.
81 uint32_t last_pid_sent;
84 * ID of the last packet received from the peer.
86 uint32_t last_pid_recv;
89 * Last ACK sent to the peer (peer can't send more than this PID).
91 uint32_t last_ack_sent;
94 * Last ACK sent towards the origin (for traffic towards leaf node).
96 uint32_t last_ack_recv;
99 * Task to poll the peer in case of a lost ACK causes stall.
101 GNUNET_SCHEDULER_TaskIdentifier poll_task;
104 * How frequently to poll for ACKs.
106 struct GNUNET_TIME_Relative poll_time;
109 * Queued poll message, to cancel if not necessary anymore (got ACK).
111 struct MeshConnectionQueue *poll_msg;
114 * Queued poll message, to cancel if not necessary anymore (got ACK).
116 struct MeshConnectionQueue *ack_msg;
120 * Keep a record of the last messages sent on this connection.
122 struct MeshConnectionPerformance
125 * Circular buffer for storing measurements.
127 double usecsperbyte[AVG_MSGS];
130 * Running average of @c usecsperbyte.
135 * How many values of @c usecsperbyte are valid.
140 * Index of the next "free" position in @c usecsperbyte.
147 * Struct containing all information regarding a connection to a peer.
149 struct MeshConnection
152 * Tunnel this connection is part of.
154 struct MeshTunnel3 *t;
157 * Flow control information for traffic fwd.
159 struct MeshFlowControl fwd_fc;
162 * Flow control information for traffic bck.
164 struct MeshFlowControl bck_fc;
167 * Measure connection performance on the endpoint.
169 struct MeshConnectionPerformance *perf;
172 * ID of the connection.
174 struct GNUNET_HashCode id;
177 * State of the connection.
179 enum MeshConnectionState state;
182 * Path being used for the tunnel. At the origin of the connection
183 * it's a pointer to the destination's path pool, otherwise just a copy.
185 struct MeshPeerPath *path;
188 * Position of the local peer in the path.
190 unsigned int own_pos;
193 * Task to keep the used paths alive at the owner,
194 * time tunnel out on all the other peers.
196 GNUNET_SCHEDULER_TaskIdentifier fwd_maintenance_task;
199 * Task to keep the used paths alive at the destination,
200 * time tunnel out on all the other peers.
202 GNUNET_SCHEDULER_TaskIdentifier bck_maintenance_task;
205 * Pending message count.
207 int pending_messages;
210 * Destroy flag: if true, destroy on last message.
216 * Handle for messages queued but not yet sent.
218 struct MeshConnectionQueue
221 * Peer queue handle, to cancel if necessary.
223 struct MeshPeerQueue *q;
226 * Was this a forced message? (Do not account for it)
231 * Continuation to call once sent.
236 * Closure for @c cont.
241 /******************************************************************************/
242 /******************************* GLOBALS ***********************************/
243 /******************************************************************************/
246 * Global handle to the statistics service.
248 extern struct GNUNET_STATISTICS_Handle *stats;
251 * Local peer own ID (memory efficient handle).
253 extern GNUNET_PEER_Id myid;
256 * Local peer own ID (full value).
258 extern struct GNUNET_PeerIdentity my_full_id;
261 * Connections known, indexed by cid (MeshConnection).
263 static struct GNUNET_CONTAINER_MultiHashMap *connections;
266 * How many connections are we willing to maintain.
267 * Local connections are always allowed, even if there are more connections than max.
269 static unsigned long long max_connections;
272 * How many messages *in total* are we willing to queue, divide by number of
273 * connections to get connection queue size.
275 static unsigned long long max_msgs_queue;
278 * How often to send path keepalives. Paths timeout after 4 missed.
280 static struct GNUNET_TIME_Relative refresh_connection_time;
283 * How often to send path create / ACKs.
285 static struct GNUNET_TIME_Relative create_connection_time;
288 /******************************************************************************/
289 /******************************** STATIC ***********************************/
290 /******************************************************************************/
292 #if 0 // avoid compiler warning for unused static function
294 fc_debug (struct MeshFlowControl *fc)
296 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
297 fc->last_pid_recv, fc->last_ack_sent);
298 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
299 fc->last_pid_sent, fc->last_ack_recv);
300 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
301 fc->queue_n, fc->queue_max);
305 connection_debug (struct MeshConnection *c)
309 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CONNECTION ***\n");
312 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
313 peer2s (c->t->peer), GMC_2s (c));
314 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
315 c->state, c->pending_messages);
316 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
317 fc_debug (&c->fwd_fc);
318 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
319 fc_debug (&c->bck_fc);
324 * Get string description for tunnel state.
326 * @param s Tunnel state.
328 * @return String representation.
331 GMC_state2s (enum MeshConnectionState s)
335 case MESH_CONNECTION_NEW:
336 return "MESH_CONNECTION_NEW";
337 case MESH_CONNECTION_SENT:
338 return "MESH_CONNECTION_SENT";
339 case MESH_CONNECTION_ACK:
340 return "MESH_CONNECTION_ACK";
341 case MESH_CONNECTION_READY:
342 return "MESH_CONNECTION_READY";
343 case MESH_CONNECTION_DESTROYED:
344 return "MESH_CONNECTION_DESTROYED";
346 return "MESH_CONNECTION_STATE_ERROR";
352 * Initialize a Flow Control structure to the initial state.
354 * @param fc Flow Control structure to initialize.
357 fc_init (struct MeshFlowControl *fc)
360 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
361 fc->last_pid_recv = (uint32_t) -1;
362 fc->last_ack_sent = (uint32_t) 0;
363 fc->last_ack_recv = (uint32_t) 0;
364 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
365 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
367 fc->queue_max = (max_msgs_queue / max_connections) + 1;
374 * @param cid Connection ID.
376 static struct MeshConnection *
377 connection_get (const struct GNUNET_HashCode *cid)
379 return GNUNET_CONTAINER_multihashmap_get (connections, cid);
384 connection_change_state (struct MeshConnection* c,
385 enum MeshConnectionState state)
387 LOG (GNUNET_ERROR_TYPE_DEBUG,
388 "Connection %s state was %s\n",
389 GMC_2s (c), GMC_state2s (c->state));
390 if (MESH_CONNECTION_DESTROYED == c->state)
392 LOG (GNUNET_ERROR_TYPE_DEBUG, "state not changing anymore\n");
395 LOG (GNUNET_ERROR_TYPE_DEBUG,
396 "Connection %s state is now %s\n",
397 GMC_2s (c), GMC_state2s (state));
403 * Callback called when a queued ACK message is sent.
405 * @param cls Closure (FC).
406 * @param c Connection this message was on.
407 * @param q Queue handler this call invalidates.
408 * @param type Type of message sent.
409 * @param fwd Was this a FWD going message?
410 * @param size Size of the message.
414 struct MeshConnection *c,
415 struct MeshConnectionQueue *q,
416 uint16_t type, int fwd, size_t size)
418 struct MeshFlowControl *fc = cls;
425 * Send an ACK on the connection, informing the predecessor about
426 * the available buffer space. Should not be called in case the peer
427 * is origin (no predecessor) in the @c fwd direction.
429 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
430 * the ACK itself goes "back" (dest->root).
432 * @param c Connection on which to send the ACK.
433 * @param buffer How much space free to advertise?
434 * @param fwd Is this FWD ACK? (Going dest -> root)
435 * @param force Don't optimize out.
438 send_ack (struct MeshConnection *c, unsigned int buffer, int fwd, int force)
440 struct MeshFlowControl *next_fc;
441 struct MeshFlowControl *prev_fc;
442 struct GNUNET_MESH_ACK msg;
446 /* If origin, there is no connection to send ACKs. Wrong function! */
447 if (GMC_is_origin (c, fwd))
449 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection %s is origin in %s\n",
450 GMC_2s (c), GM_f2s (fwd));
455 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
456 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
458 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection send %s ack on %s\n",
459 GM_f2s (fwd), GMC_2s (c));
461 /* Check if we need to transmit the ACK. */
462 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
463 if (3 < delta && buffer < delta && GNUNET_NO == force)
465 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
466 LOG (GNUNET_ERROR_TYPE_DEBUG,
467 " last pid recv: %u, last ack sent: %u\n",
468 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
472 /* Ok, ACK might be necessary, what PID to ACK? */
473 ack = prev_fc->last_pid_recv + buffer;
474 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
475 LOG (GNUNET_ERROR_TYPE_DEBUG,
476 " last pid %u, last ack %u, qmax %u, q %u\n",
477 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
478 next_fc->queue_max, next_fc->queue_n);
479 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
481 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
485 /* Check if message is already in queue */
486 if (NULL != prev_fc->ack_msg)
488 if (GM_is_pid_bigger (ack, prev_fc->last_ack_sent))
490 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
491 GMC_cancel (prev_fc->ack_msg);
492 /* GMC_cancel triggers ack_sent(), which clears fc->ack_msg */
496 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
501 prev_fc->last_ack_sent = ack;
503 /* Build ACK message and send on connection */
504 msg.header.size = htons (sizeof (msg));
505 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_ACK);
506 msg.ack = htonl (ack);
509 prev_fc->ack_msg = GMC_send_prebuilt_message (&msg.header, c,
516 * Callback called when a queued message is sent.
518 * Calculates the average time and connection packet tracking.
520 * @param cls Closure (ConnectionQueue Handle).
521 * @param c Connection this message was on.
522 * @param type Type of message sent.
523 * @param fwd Was this a FWD going message?
524 * @param size Size of the message.
525 * @param wait Time spent waiting for core (only the time for THIS message)
528 message_sent (void *cls,
529 struct MeshConnection *c, uint16_t type,
530 int fwd, size_t size,
531 struct GNUNET_TIME_Relative wait)
533 struct MeshConnectionPerformance *p;
534 struct MeshFlowControl *fc;
535 struct MeshConnectionQueue *q = cls;
539 fc = fwd ? &c->fwd_fc : &c->bck_fc;
540 LOG (GNUNET_ERROR_TYPE_DEBUG,
544 LOG (GNUNET_ERROR_TYPE_DEBUG, "! C_P- %p %u\n", c, c->pending_messages);
550 LOG (GNUNET_ERROR_TYPE_DEBUG, "! calling cont\n");
551 q->cont (q->cont_cls, c, q, type, fwd, size);
555 else if (type == GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED)
557 /* If NULL == q and ENCRYPTED == type, message must have been ch_mngmnt */
564 c->pending_messages--;
565 if (GNUNET_YES == c->destroy && 0 == c->pending_messages)
567 LOG (GNUNET_ERROR_TYPE_DEBUG, "! destroying connection!\n");
571 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
574 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
576 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
577 if (GNUNET_NO == forced)
580 LOG (GNUNET_ERROR_TYPE_DEBUG,
581 "! accounting pid %u\n",
586 LOG (GNUNET_ERROR_TYPE_DEBUG,
587 "! forced, Q_N not accounting pid %u\n",
590 GMC_send_ack (c, fwd, GNUNET_NO);
593 case GNUNET_MESSAGE_TYPE_MESH_POLL:
597 case GNUNET_MESSAGE_TYPE_MESH_ACK:
604 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
607 return; /* Only endpoints are interested in timing. */
610 usecsperbyte = ((double) wait.rel_value_us) / size;
611 if (p->size == AVG_MSGS)
613 /* Array is full. Substract oldest value, add new one and store. */
614 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
615 p->usecsperbyte[p->idx] = usecsperbyte;
616 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
620 /* Array not yet full. Add current value to avg and store. */
621 p->usecsperbyte[p->idx] = usecsperbyte;
623 p->avg += p->usecsperbyte[p->idx];
627 p->idx = (p->idx + 1) % AVG_MSGS;
632 * Get the previous hop in a connection
634 * @param c Connection.
636 * @return Previous peer in the connection.
638 static struct MeshPeer *
639 get_prev_hop (const struct MeshConnection *c)
643 LOG (GNUNET_ERROR_TYPE_DEBUG, " get prev hop %s [%u/%u]\n",
644 GMC_2s (c), c->own_pos, c->path->length);
645 if (0 == c->own_pos || c->path->length < 2)
647 LOG (GNUNET_ERROR_TYPE_DEBUG, " own pos is zero\n");
648 id = c->path->peers[0];
652 LOG (GNUNET_ERROR_TYPE_DEBUG, " own pos is NOT zero\n");
653 id = c->path->peers[c->own_pos - 1];
656 LOG (GNUNET_ERROR_TYPE_DEBUG, " id: %u\n", id);
657 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s\n", GNUNET_i2s (GNUNET_PEER_resolve2 (id)));
658 return GMP_get_short (id);
663 * Get the next hop in a connection
665 * @param c Connection.
667 * @return Next peer in the connection.
669 static struct MeshPeer *
670 get_next_hop (const struct MeshConnection *c)
674 LOG (GNUNET_ERROR_TYPE_DEBUG, " get next hop %s [%u/%u]\n",
675 GMC_2s (c), c->own_pos, c->path->length);
676 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
678 LOG (GNUNET_ERROR_TYPE_DEBUG, " own pos is end\n");
679 id = c->path->peers[c->path->length - 1];
683 LOG (GNUNET_ERROR_TYPE_DEBUG, " own pos is NOT end\n");
684 id = c->path->peers[c->own_pos + 1];
687 LOG (GNUNET_ERROR_TYPE_DEBUG, " id: %u\n", id);
688 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s\n", GNUNET_i2s (GNUNET_PEER_resolve2 (id)));
690 return GMP_get_short (id);
695 * Get the hop in a connection.
697 * @param c Connection.
698 * @param fwd Next hop?
700 * @return Next peer in the connection.
702 static struct MeshPeer *
703 get_hop (struct MeshConnection *c, int fwd)
706 return get_next_hop (c);
707 return get_prev_hop (c);
712 * Is traffic coming from this sender 'FWD' traffic?
714 * @param c Connection to check.
715 * @param sender Peer identity of neighbor.
717 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
718 * the traffic is 'FWD'.
719 * #GNUNET_NO for BCK.
720 * #GNUNET_SYSERR for errors.
723 is_fwd (const struct MeshConnection *c,
724 const struct GNUNET_PeerIdentity *sender)
728 id = GNUNET_PEER_search (sender);
729 if (GMP_get_short_id (get_prev_hop (c)) == id)
732 if (GMP_get_short_id (get_next_hop (c)) == id)
736 return GNUNET_SYSERR;
741 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
742 * or a first CONNECTION_ACK directed to us.
744 * @param connection Connection to confirm.
745 * @param fwd Should we send it FWD? (root->dest)
746 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
749 send_connection_ack (struct MeshConnection *connection, int fwd)
751 struct MeshTunnel3 *t;
754 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection %s ACK\n",
756 GMP_queue_add (get_hop (connection, fwd), NULL,
757 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK,
758 sizeof (struct GNUNET_MESH_ConnectionACK),
759 connection, fwd, &message_sent, NULL);
760 connection->pending_messages++;
761 if (MESH_TUNNEL3_NEW == GMT_get_cstate (t))
762 GMT_change_cstate (t, MESH_TUNNEL3_WAITING);
763 if (MESH_CONNECTION_READY != connection->state)
764 connection_change_state (connection, MESH_CONNECTION_SENT);
769 * Send a notification that a connection is broken.
771 * @param c Connection that is broken.
772 * @param id1 Peer that has disconnected.
773 * @param id2 Peer that has disconnected.
774 * @param fwd Direction towards which to send it.
777 send_broken (struct MeshConnection *c,
778 const struct GNUNET_PeerIdentity *id1,
779 const struct GNUNET_PeerIdentity *id2,
782 struct GNUNET_MESH_ConnectionBroken msg;
784 msg.header.size = htons (sizeof (struct GNUNET_MESH_ConnectionBroken));
785 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN);
789 GMC_send_prebuilt_message (&msg.header, c, fwd, GNUNET_YES, NULL, NULL);
794 * Send keepalive packets for a connection.
796 * @param c Connection to keep alive..
797 * @param fwd Is this a FWD keepalive? (owner -> dest).
800 connection_keepalive (struct MeshConnection *c, int fwd)
802 struct GNUNET_MESH_ConnectionKeepAlive *msg;
803 size_t size = sizeof (struct GNUNET_MESH_ConnectionKeepAlive);
806 LOG (GNUNET_ERROR_TYPE_DEBUG,
807 "sending %s keepalive for connection %s]\n",
808 GM_f2s (fwd), GMC_2s (c));
810 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) cbuf;
811 msg->header.size = htons (size);
812 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KEEPALIVE);
814 msg->reserved = htonl (0);
816 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_YES, NULL, NULL);
821 * Send CONNECTION_{CREATE/ACK} packets for a connection.
823 * @param c Connection for which to send the message.
824 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
827 connection_recreate (struct MeshConnection *c, int fwd)
829 LOG (GNUNET_ERROR_TYPE_DEBUG, "sending connection recreate\n");
833 send_connection_ack (c, GNUNET_NO);
838 * Generic connection timer management.
839 * Depending on the role of the peer in the connection will send the
840 * appropriate message (build or keepalive)
842 * @param c Conncetion to maintain.
846 connection_maintain (struct MeshConnection *c, int fwd)
848 if (GNUNET_NO != c->destroy)
851 if (MESH_TUNNEL3_SEARCHING == GMT_get_cstate (c->t))
853 /* TODO DHT GET with RO_BART */
858 case MESH_CONNECTION_NEW:
861 case MESH_CONNECTION_SENT:
862 connection_recreate (c, fwd);
864 case MESH_CONNECTION_READY:
865 connection_keepalive (c, fwd);
874 connection_fwd_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
876 struct MeshConnection *c = cls;
877 struct GNUNET_TIME_Relative delay;
879 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
880 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
883 connection_maintain (c, GNUNET_YES);
884 delay = c->state == MESH_CONNECTION_READY ?
885 refresh_connection_time : create_connection_time;
886 c->fwd_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
887 &connection_fwd_keepalive,
893 connection_bck_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
895 struct MeshConnection *c = cls;
896 struct GNUNET_TIME_Relative delay;
898 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
899 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
902 connection_maintain (c, GNUNET_NO);
903 delay = c->state == MESH_CONNECTION_READY ?
904 refresh_connection_time : create_connection_time;
905 c->bck_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
906 &connection_bck_keepalive,
912 * @brief Re-initiate traffic on this connection if necessary.
914 * Check if there is traffic queued towards this peer
915 * and the core transmit handle is NULL (traffic was stalled).
916 * If so, call core tmt rdy.
918 * @param c Connection on which initiate traffic.
919 * @param fwd Is this about fwd traffic?
922 connection_unlock_queue (struct MeshConnection *c, int fwd)
924 struct MeshPeer *peer;
926 LOG (GNUNET_ERROR_TYPE_DEBUG,
927 "connection_unlock_queue %s on %s\n",
928 GM_f2s (fwd), GMC_2s (c));
930 if (GMC_is_terminal (c, fwd))
932 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal!\n");
936 peer = get_hop (c, fwd);
937 GMP_queue_unlock (peer, c);
942 * Cancel all transmissions that belong to a certain connection.
944 * If the connection is scheduled for destruction and no more messages are left,
945 * the connection will be destroyed by the continuation call.
947 * @param c Connection which to cancel. Might be destroyed during this call.
948 * @param fwd Cancel fwd traffic?
951 connection_cancel_queues (struct MeshConnection *c, int fwd)
953 struct MeshFlowControl *fc;
954 struct MeshPeer *peer;
956 LOG (GNUNET_ERROR_TYPE_DEBUG,
957 " *** Cancel %s queues for connection %s\n",
958 GM_f2s (fwd), GMC_2s (c));
965 fc = fwd ? &c->fwd_fc : &c->bck_fc;
966 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
968 GNUNET_SCHEDULER_cancel (fc->poll_task);
969 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
970 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Cancel POLL in ccq for fc %p\n", fc);
972 peer = get_hop (c, fwd);
973 GMP_queue_cancel (peer, c);
978 * Function called if a connection has been stalled for a while,
979 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
981 * @param cls Closure (poll ctx).
982 * @param tc TaskContext.
985 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
989 * Callback called when a queued POLL message is sent.
991 * @param cls Closure (FC).
992 * @param c Connection this message was on.
993 * @param q Queue handler this call invalidates.
994 * @param type Type of message sent.
995 * @param fwd Was this a FWD going message?
996 * @param size Size of the message.
999 poll_sent (void *cls,
1000 struct MeshConnection *c,
1001 struct MeshConnectionQueue *q,
1002 uint16_t type, int fwd, size_t size)
1004 struct MeshFlowControl *fc = cls;
1006 if (2 == c->destroy)
1008 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL canceled on shutdown\n");
1011 LOG (GNUNET_ERROR_TYPE_DEBUG,
1012 " *** POLL sent for , scheduling new one!\n");
1013 fc->poll_msg = NULL;
1014 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1015 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1016 &connection_poll, fc);
1017 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1022 * Function called if a connection has been stalled for a while,
1023 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1025 * @param cls Closure (poll ctx).
1026 * @param tc TaskContext.
1029 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1031 struct MeshFlowControl *fc = cls;
1032 struct GNUNET_MESH_Poll msg;
1033 struct MeshConnection *c;
1035 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1036 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1042 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Polling!\n");
1043 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** connection [%s]\n", GMC_2s (c));
1044 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** %s\n",
1045 fc == &c->fwd_fc ? "FWD" : "BCK");
1047 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_POLL);
1048 msg.header.size = htons (sizeof (msg));
1049 msg.pid = htonl (fc->last_pid_sent);
1050 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** last pid sent: %u!\n", fc->last_pid_sent);
1051 fc->poll_msg = GMC_send_prebuilt_message (&msg.header, c,
1052 fc == &c->fwd_fc, GNUNET_YES,
1058 * Timeout function due to lack of keepalive/traffic from the owner.
1059 * Destroys connection if called.
1061 * @param cls Closure (connection to destroy).
1062 * @param tc TaskContext.
1065 connection_fwd_timeout (void *cls,
1066 const struct GNUNET_SCHEDULER_TaskContext *tc)
1068 struct MeshConnection *c = cls;
1070 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1071 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1074 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s FWD timed out. Destroying.\n",
1076 if (GMC_is_origin (c, GNUNET_YES)) /* If local, leave. */
1087 * Timeout function due to lack of keepalive/traffic from the destination.
1088 * Destroys connection if called.
1090 * @param cls Closure (connection to destroy).
1091 * @param tc TaskContext
1094 connection_bck_timeout (void *cls,
1095 const struct GNUNET_SCHEDULER_TaskContext *tc)
1097 struct MeshConnection *c = cls;
1099 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1100 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1103 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s BCK timed out. Destroying.\n",
1106 if (GMC_is_origin (c, GNUNET_NO)) /* If local, leave. */
1117 * Resets the connection timeout task, some other message has done the
1119 * - For the first peer on the direction this means to send
1120 * a keepalive or a path confirmation message (either create or ACK).
1121 * - For all other peers, this means to destroy the connection,
1122 * due to lack of activity.
1123 * Starts the timeout if no timeout was running (connection just created).
1125 * @param c Connection whose timeout to reset.
1126 * @param fwd Is this forward?
1128 * TODO use heap to improve efficiency of scheduler.
1131 connection_reset_timeout (struct MeshConnection *c, int fwd)
1133 GNUNET_SCHEDULER_TaskIdentifier *ti;
1134 GNUNET_SCHEDULER_Task f;
1136 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1138 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GM_f2s (fwd));
1140 if (GNUNET_SCHEDULER_NO_TASK != *ti)
1141 GNUNET_SCHEDULER_cancel (*ti);
1143 if (GMC_is_origin (c, fwd)) /* Startpoint */
1145 f = fwd ? &connection_fwd_keepalive : &connection_bck_keepalive;
1146 *ti = GNUNET_SCHEDULER_add_delayed (refresh_connection_time, f, c);
1148 else /* Relay, endpoint. */
1150 struct GNUNET_TIME_Relative delay;
1152 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1153 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1154 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1160 * Add the connection to the list of both neighbors.
1162 * @param c Connection.
1164 * @return #GNUNET_OK if everything went fine
1165 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1168 register_neighbors (struct MeshConnection *c)
1170 struct MeshPeer *next_peer;
1171 struct MeshPeer *prev_peer;
1173 next_peer = get_next_hop (c);
1174 prev_peer = get_prev_hop (c);
1176 LOG (GNUNET_ERROR_TYPE_DEBUG, "register neighbors for connection %s\n",
1178 path_debug (c->path);
1179 LOG (GNUNET_ERROR_TYPE_DEBUG, "own pos %u\n", c->own_pos);
1180 LOG (GNUNET_ERROR_TYPE_DEBUG, "putting connection %s to next peer %p\n",
1181 GMC_2s (c), next_peer);
1182 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n", next_peer, GMP_2s (next_peer));
1183 LOG (GNUNET_ERROR_TYPE_DEBUG, "putting connection %s to prev peer %p\n",
1184 GMC_2s (c), prev_peer);
1185 LOG (GNUNET_ERROR_TYPE_DEBUG, "prev peer %p %s\n", prev_peer, GMP_2s (prev_peer));
1187 if (GNUNET_NO == GMP_is_neighbor (next_peer)
1188 || GNUNET_NO == GMP_is_neighbor (prev_peer))
1190 if (GMC_is_origin (c, GNUNET_YES))
1191 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1192 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1194 LOG (GNUNET_ERROR_TYPE_DEBUG, " register neighbors failed\n");
1195 LOG (GNUNET_ERROR_TYPE_DEBUG, " prev: %s, neighbor?: %d\n",
1196 GMP_2s (prev_peer), GMP_is_neighbor (prev_peer));
1197 LOG (GNUNET_ERROR_TYPE_DEBUG, " next: %s, neighbor?: %d\n",
1198 GMP_2s (next_peer), GMP_is_neighbor (next_peer));
1199 return GNUNET_SYSERR;
1202 GMP_add_connection (next_peer, c);
1203 GMP_add_connection (prev_peer, c);
1210 * Remove the connection from the list of both neighbors.
1212 * @param c Connection.
1215 unregister_neighbors (struct MeshConnection *c)
1217 struct MeshPeer *peer;
1219 peer = get_next_hop (c);
1220 if (GNUNET_OK != GMP_remove_connection (peer, c))
1222 GNUNET_assert (MESH_CONNECTION_NEW == c->state
1223 || MESH_CONNECTION_DESTROYED == c->state);
1224 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate: %u\n", c->state);
1225 if (NULL != c->t) GMT_debug (c->t);
1228 peer = get_prev_hop (c);
1229 if (GNUNET_OK != GMP_remove_connection (peer, c))
1231 GNUNET_assert (MESH_CONNECTION_NEW == c->state
1232 || MESH_CONNECTION_DESTROYED == c->state);
1233 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate: %u\n", c->state);
1234 if (NULL != c->t) GMT_debug (c->t);
1240 * Bind the connection to the peer and the tunnel to that peer.
1242 * If the peer has no tunnel, create one. Update tunnel and connection
1243 * data structres to reflect new status.
1245 * @param c Connection.
1249 add_to_peer (struct MeshConnection *c, struct MeshPeer *peer)
1251 GMP_add_tunnel (peer);
1252 c->t = GMP_get_tunnel (peer);
1253 GMT_add_connection (c->t, c);
1258 * Builds a path from a PeerIdentity array.
1260 * @param peers PeerIdentity array.
1261 * @param size Size of the @c peers array.
1262 * @param own_pos Output parameter: own position in the path.
1264 * @return Fixed and shortened path.
1266 static struct MeshPeerPath *
1267 build_path_from_peer_ids (struct GNUNET_PeerIdentity *peers,
1269 unsigned int *own_pos)
1271 struct MeshPeerPath *path;
1272 GNUNET_PEER_Id shortid;
1275 unsigned int offset;
1278 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating path...\n");
1279 path = path_new (size);
1282 for (i = 0; i < size; i++)
1284 LOG (GNUNET_ERROR_TYPE_DEBUG, " - %u: taking %s\n",
1285 i, GNUNET_i2s (&peers[i]));
1286 shortid = GNUNET_PEER_intern (&peers[i]);
1288 /* Check for loops / duplicates */
1289 for (j = 0; j < i - offset; j++)
1291 if (path->peers[j] == shortid)
1293 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists at pos %u\n", j);
1295 LOG (GNUNET_ERROR_TYPE_DEBUG, " offset now\n", offset);
1296 GNUNET_PEER_change_rc (shortid, -1);
1299 LOG (GNUNET_ERROR_TYPE_DEBUG, " storing at %u\n", i - offset);
1300 path->peers[i - offset] = shortid;
1301 if (path->peers[i] == myid)
1304 path->length -= offset;
1306 if (path->peers[*own_pos] != myid)
1308 /* create path: self not found in path through self */
1309 GNUNET_break_op (0);
1310 path_destroy (path);
1317 /******************************************************************************/
1318 /******************************** API ***********************************/
1319 /******************************************************************************/
1322 * Core handler for connection creation.
1324 * @param cls Closure (unused).
1325 * @param peer Sender (neighbor).
1326 * @param message Message.
1328 * @return GNUNET_OK to keep the connection open,
1329 * GNUNET_SYSERR to close it (signal serious error)
1332 GMC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
1333 const struct GNUNET_MessageHeader *message)
1335 struct GNUNET_MESH_ConnectionCreate *msg;
1336 struct GNUNET_PeerIdentity *id;
1337 struct GNUNET_HashCode *cid;
1338 struct MeshPeerPath *path;
1339 struct MeshPeer *dest_peer;
1340 struct MeshPeer *orig_peer;
1341 struct MeshConnection *c;
1342 unsigned int own_pos;
1345 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1346 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection create msg\n");
1349 size = ntohs (message->size);
1350 if (size < sizeof (struct GNUNET_MESH_ConnectionCreate))
1352 GNUNET_break_op (0);
1356 /* Calculate hops */
1357 size -= sizeof (struct GNUNET_MESH_ConnectionCreate);
1358 if (size % sizeof (struct GNUNET_PeerIdentity))
1360 GNUNET_break_op (0);
1363 size /= sizeof (struct GNUNET_PeerIdentity);
1366 GNUNET_break_op (0);
1369 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1371 /* Get parameters */
1372 msg = (struct GNUNET_MESH_ConnectionCreate *) message;
1374 id = (struct GNUNET_PeerIdentity *) &msg[1];
1375 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s (%s->).\n",
1376 GNUNET_h2s (cid), GNUNET_i2s (id));
1378 /* Create connection */
1379 c = connection_get (cid);
1382 path = build_path_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
1386 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1387 GMP_add_path_to_all (path, GNUNET_NO);
1388 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1389 c = GMC_new (cid, NULL, path_duplicate (path), own_pos);
1392 path_destroy (path);
1395 connection_reset_timeout (c, GNUNET_YES);
1399 path = path_duplicate (c->path);
1401 if (MESH_CONNECTION_NEW == c->state)
1402 connection_change_state (c, MESH_CONNECTION_SENT);
1404 /* Remember peers */
1405 dest_peer = GMP_get (&id[size - 1]);
1406 orig_peer = GMP_get (&id[0]);
1408 /* Is it a connection to us? */
1409 if (c->own_pos == size - 1)
1411 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1412 GMP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
1414 add_to_peer (c, orig_peer);
1415 if (MESH_TUNNEL3_NEW == GMT_get_cstate (c->t))
1416 GMT_change_cstate (c->t, MESH_TUNNEL3_WAITING);
1418 send_connection_ack (c, GNUNET_NO);
1419 if (MESH_CONNECTION_SENT == c->state)
1420 connection_change_state (c, MESH_CONNECTION_ACK);
1422 /* Keep tunnel alive in direction dest->owner*/
1423 if (GNUNET_SCHEDULER_NO_TASK == c->bck_maintenance_task)
1425 c->bck_maintenance_task =
1426 GNUNET_SCHEDULER_add_delayed (create_connection_time,
1427 &connection_bck_keepalive, c);
1432 /* It's for somebody else! Retransmit. */
1433 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
1434 GMP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1435 GMP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
1436 GMC_send_prebuilt_message (message, c, GNUNET_YES, GNUNET_YES,
1439 path_destroy (path);
1445 * Core handler for path confirmations.
1447 * @param cls closure
1448 * @param message message
1449 * @param peer peer identity this notification is about
1451 * @return GNUNET_OK to keep the connection open,
1452 * GNUNET_SYSERR to close it (signal serious error)
1455 GMC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
1456 const struct GNUNET_MessageHeader *message)
1458 struct GNUNET_MESH_ConnectionACK *msg;
1459 struct MeshConnection *c;
1460 struct MeshPeerPath *p;
1461 struct MeshPeer *pi;
1462 enum MeshConnectionState oldstate;
1465 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1466 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection ACK msg\n");
1467 msg = (struct GNUNET_MESH_ConnectionACK *) message;
1468 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n",
1469 GNUNET_h2s (&msg->cid));
1470 c = connection_get (&msg->cid);
1473 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1475 LOG (GNUNET_ERROR_TYPE_DEBUG, " don't know the connection!\n");
1479 if (GNUNET_NO != c->destroy)
1481 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection being destroyed\n");
1485 oldstate = c->state;
1486 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
1487 pi = GMP_get (peer);
1488 if (get_next_hop (c) == pi)
1490 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
1492 if (MESH_CONNECTION_SENT == oldstate)
1493 connection_change_state (c, MESH_CONNECTION_ACK);
1495 else if (get_prev_hop (c) == pi)
1497 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK\n");
1499 connection_change_state (c, MESH_CONNECTION_READY);
1503 GNUNET_break_op (0);
1507 connection_reset_timeout (c, fwd);
1509 /* Add path to peers? */
1513 GMP_add_path_to_all (p, GNUNET_YES);
1520 /* Message for us as creator? */
1521 if (GMC_is_origin (c, GNUNET_YES))
1523 if (GNUNET_NO != fwd)
1525 GNUNET_break_op (0);
1528 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
1530 /* If just created, cancel the short timeout and start a long one */
1531 if (MESH_CONNECTION_SENT == oldstate)
1532 connection_reset_timeout (c, GNUNET_YES);
1534 /* Change connection state */
1535 connection_change_state (c, MESH_CONNECTION_READY);
1536 send_connection_ack (c, GNUNET_YES);
1538 /* Change tunnel state, trigger KX */
1539 if (MESH_TUNNEL3_WAITING == GMT_get_cstate (c->t))
1540 GMT_change_cstate (c->t, MESH_TUNNEL3_READY);
1545 /* Message for us as destination? */
1546 if (GMC_is_terminal (c, GNUNET_YES))
1548 if (GNUNET_YES != fwd)
1550 GNUNET_break_op (0);
1553 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
1555 /* If just created, cancel the short timeout and start a long one */
1556 if (MESH_CONNECTION_ACK == oldstate)
1557 connection_reset_timeout (c, GNUNET_NO);
1559 /* Change tunnel state */
1560 if (MESH_TUNNEL3_WAITING == GMT_get_cstate (c->t))
1561 GMT_change_cstate (c->t, MESH_TUNNEL3_READY);
1566 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1567 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
1573 * Core handler for notifications of broken paths
1575 * @param cls Closure (unused).
1576 * @param id Peer identity of sending neighbor.
1577 * @param message Message.
1579 * @return GNUNET_OK to keep the connection open,
1580 * GNUNET_SYSERR to close it (signal serious error)
1583 GMC_handle_broken (void* cls,
1584 const struct GNUNET_PeerIdentity* id,
1585 const struct GNUNET_MessageHeader* message)
1587 struct GNUNET_MESH_ConnectionBroken *msg;
1588 struct MeshConnection *c;
1591 LOG (GNUNET_ERROR_TYPE_DEBUG,
1592 "Received a CONNECTION BROKEN msg from %s\n", GNUNET_i2s (id));
1593 msg = (struct GNUNET_MESH_ConnectionBroken *) message;
1594 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1595 GNUNET_i2s (&msg->peer1));
1596 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1597 GNUNET_i2s (&msg->peer2));
1598 c = connection_get (&msg->cid);
1601 GNUNET_break_op (0);
1605 fwd = is_fwd (c, id);
1606 if (GMC_is_terminal (c, fwd))
1608 if (0 < c->pending_messages)
1609 c->destroy = GNUNET_YES;
1615 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
1616 c->destroy = GNUNET_YES;
1617 connection_cancel_queues (c, !fwd);
1626 * Core handler for tunnel destruction
1628 * @param cls Closure (unused).
1629 * @param peer Peer identity of sending neighbor.
1630 * @param message Message.
1632 * @return GNUNET_OK to keep the connection open,
1633 * GNUNET_SYSERR to close it (signal serious error)
1636 GMC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
1637 const struct GNUNET_MessageHeader *message)
1639 struct GNUNET_MESH_ConnectionDestroy *msg;
1640 struct MeshConnection *c;
1643 msg = (struct GNUNET_MESH_ConnectionDestroy *) message;
1644 LOG (GNUNET_ERROR_TYPE_DEBUG,
1645 "Got a CONNECTION DESTROY message from %s\n",
1647 LOG (GNUNET_ERROR_TYPE_DEBUG,
1648 " for connection %s\n",
1649 GNUNET_h2s (&msg->cid));
1650 c = connection_get (&msg->cid);
1653 /* Probably already got the message from another path,
1654 * destroyed the tunnel and retransmitted to children.
1657 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1659 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection unknown: already destroyed?\n");
1662 fwd = is_fwd (c, peer);
1663 if (GNUNET_SYSERR == fwd)
1665 GNUNET_break_op (0); /* FIXME */
1668 if (GNUNET_NO == GMC_is_terminal (c, fwd))
1669 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
1670 else if (0 == c->pending_messages)
1672 LOG (GNUNET_ERROR_TYPE_DEBUG, "! directly destroying connection!\n");
1676 c->destroy = GNUNET_YES;
1677 c->state = MESH_CONNECTION_DESTROYED;
1680 GMT_remove_connection (c->t, c);
1688 * Generic handler for mesh network encrypted traffic.
1690 * @param peer Peer identity this notification is about.
1691 * @param msg Encrypted message.
1693 * @return GNUNET_OK to keep the connection open,
1694 * GNUNET_SYSERR to close it (signal serious error)
1697 handle_mesh_encrypted (const struct GNUNET_PeerIdentity *peer,
1698 const struct GNUNET_MESH_Encrypted *msg)
1700 struct MeshConnection *c;
1701 struct MeshPeer *neighbor;
1702 struct MeshFlowControl *fc;
1703 GNUNET_PEER_Id peer_id;
1711 size = ntohs (msg->header.size);
1713 sizeof (struct GNUNET_MESH_Encrypted) +
1714 sizeof (struct GNUNET_MessageHeader))
1716 GNUNET_break_op (0);
1719 type = ntohs (msg->header.type);
1720 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1721 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message (#%u) from %s\n",
1722 GM_m2s (type), ntohl (msg->pid), GNUNET_i2s (peer));
1724 /* Check connection */
1725 c = connection_get (&msg->cid);
1728 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1729 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING enc on unknown connection %s\n",
1730 GNUNET_h2s (&msg->cid));
1734 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n", GMC_2s (c));
1736 /* Check if origin is as expected */
1737 neighbor = get_prev_hop (c);
1738 peer_id = GNUNET_PEER_search (peer);
1739 if (peer_id == GMP_get_short_id (neighbor))
1745 neighbor = get_next_hop (c);
1746 if (peer_id == GMP_get_short_id (neighbor))
1752 /* Unexpected peer sending traffic on a connection. */
1753 GNUNET_break_op (0);
1759 fc = fwd ? &c->bck_fc : &c->fwd_fc;
1760 pid = ntohl (msg->pid);
1761 if (GM_is_pid_bigger (pid, fc->last_ack_sent))
1763 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
1764 LOG (GNUNET_ERROR_TYPE_DEBUG,
1765 "WARNING Received PID %u, (prev %u), ACK %u\n",
1766 pid, fc->last_pid_recv, fc->last_ack_sent);
1769 if (GNUNET_NO == GM_is_pid_bigger (pid, fc->last_pid_recv))
1771 GNUNET_STATISTICS_update (stats, "# duplicate PID", 1, GNUNET_NO);
1772 LOG (GNUNET_ERROR_TYPE_DEBUG,
1773 " Pid %u not expected (%u+), dropping!\n",
1774 pid, fc->last_pid_recv + 1);
1777 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1778 connection_change_state (c, MESH_CONNECTION_READY);
1779 connection_reset_timeout (c, fwd);
1780 fc->last_pid_recv = pid;
1782 /* Is this message for us? */
1783 if (GMC_is_terminal (c, fwd))
1785 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1786 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1790 GNUNET_break (GNUNET_NO != c->destroy);
1793 fc->last_pid_recv = pid;
1794 GMT_handle_encrypted (c->t, msg);
1795 GMC_send_ack (c, fwd, GNUNET_NO);
1799 /* Message not for us: forward to next hop */
1800 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1801 ttl = ntohl (msg->ttl);
1802 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
1805 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
1806 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
1807 GMC_send_ack (c, fwd, GNUNET_NO);
1811 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1812 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_NO, NULL, NULL);
1818 * Generic handler for mesh network encrypted traffic.
1820 * @param peer Peer identity this notification is about.
1821 * @param msg Encrypted message.
1823 * @return GNUNET_OK to keep the connection open,
1824 * GNUNET_SYSERR to close it (signal serious error)
1827 handle_mesh_kx (const struct GNUNET_PeerIdentity *peer,
1828 const struct GNUNET_MESH_KX *msg)
1830 struct MeshConnection *c;
1831 struct MeshPeer *neighbor;
1832 GNUNET_PEER_Id peer_id;
1838 size = ntohs (msg->header.size);
1840 sizeof (struct GNUNET_MESH_Encrypted) +
1841 sizeof (struct GNUNET_MessageHeader))
1843 GNUNET_break_op (0);
1846 type = ntohs (msg->header.type);
1847 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1848 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message from %s\n",
1849 GM_m2s (type), GNUNET_i2s (peer));
1851 /* Check connection */
1852 c = connection_get (&msg->cid);
1855 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1856 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING kx on unknown connection %s\n",
1857 GNUNET_h2s (&msg->cid));
1860 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n", GMC_2s (c));
1862 /* Check if origin is as expected */
1863 neighbor = get_prev_hop (c);
1864 peer_id = GNUNET_PEER_search (peer);
1865 if (peer_id == GMP_get_short_id (neighbor))
1871 neighbor = get_next_hop (c);
1872 if (peer_id == GMP_get_short_id (neighbor))
1878 /* Unexpected peer sending traffic on a connection. */
1879 GNUNET_break_op (0);
1884 /* Count as connection confirmation. */
1885 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1887 connection_change_state (c, MESH_CONNECTION_READY);
1890 if (MESH_TUNNEL3_WAITING == GMT_get_cstate (c->t))
1891 GMT_change_cstate (c->t, MESH_TUNNEL3_READY);
1894 connection_reset_timeout (c, fwd);
1896 /* Is this message for us? */
1897 if (GMC_is_terminal (c, fwd))
1899 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1900 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1906 GMT_handle_kx (c->t, &msg[1].header);
1910 /* Message not for us: forward to next hop */
1911 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1912 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1913 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_NO, NULL, NULL);
1920 * Core handler for encrypted mesh network traffic (channel mgmt, data).
1922 * @param cls Closure (unused).
1923 * @param message Message received.
1924 * @param peer Peer who sent the message.
1926 * @return GNUNET_OK to keep the connection open,
1927 * GNUNET_SYSERR to close it (signal serious error)
1930 GMC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
1931 const struct GNUNET_MessageHeader *message)
1933 return handle_mesh_encrypted (peer,
1934 (struct GNUNET_MESH_Encrypted *)message);
1939 * Core handler for key exchange traffic (ephemeral key, ping, pong).
1941 * @param cls Closure (unused).
1942 * @param message Message received.
1943 * @param peer Peer who sent the message.
1945 * @return GNUNET_OK to keep the connection open,
1946 * GNUNET_SYSERR to close it (signal serious error)
1949 GMC_handle_kx (void *cls, const struct GNUNET_PeerIdentity *peer,
1950 const struct GNUNET_MessageHeader *message)
1952 return handle_mesh_kx (peer,
1953 (struct GNUNET_MESH_KX *) message);
1958 * Core handler for mesh network traffic point-to-point acks.
1960 * @param cls closure
1961 * @param message message
1962 * @param peer peer identity this notification is about
1964 * @return GNUNET_OK to keep the connection open,
1965 * GNUNET_SYSERR to close it (signal serious error)
1968 GMC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
1969 const struct GNUNET_MessageHeader *message)
1971 struct GNUNET_MESH_ACK *msg;
1972 struct MeshConnection *c;
1973 struct MeshFlowControl *fc;
1978 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1979 LOG (GNUNET_ERROR_TYPE_DEBUG, "Got an ACK packet from %s!\n",
1981 msg = (struct GNUNET_MESH_ACK *) message;
1983 c = connection_get (&msg->cid);
1987 GNUNET_STATISTICS_update (stats, "# ack on unknown connection", 1,
1992 /* Is this a forward or backward ACK? */
1993 id = GNUNET_PEER_search (peer);
1994 if (GMP_get_short_id (get_next_hop (c)) == id)
1996 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
2000 else if (GMP_get_short_id (get_prev_hop (c)) == id)
2002 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
2008 GNUNET_break_op (0);
2012 ack = ntohl (msg->ack);
2013 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u (was %u)\n",
2014 ack, fc->last_ack_recv);
2015 if (GM_is_pid_bigger (ack, fc->last_ack_recv))
2016 fc->last_ack_recv = ack;
2018 /* Cancel polling if the ACK is big enough. */
2019 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task &&
2020 GM_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2022 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2023 GNUNET_SCHEDULER_cancel (fc->poll_task);
2024 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2025 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2028 connection_unlock_queue (c, fwd);
2035 * Core handler for mesh network traffic point-to-point ack polls.
2037 * @param cls closure
2038 * @param message message
2039 * @param peer peer identity this notification is about
2041 * @return GNUNET_OK to keep the connection open,
2042 * GNUNET_SYSERR to close it (signal serious error)
2045 GMC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
2046 const struct GNUNET_MessageHeader *message)
2048 struct GNUNET_MESH_Poll *msg;
2049 struct MeshConnection *c;
2050 struct MeshFlowControl *fc;
2055 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
2056 LOG (GNUNET_ERROR_TYPE_DEBUG,
2057 "Got a POLL message from %s!\n",
2060 msg = (struct GNUNET_MESH_Poll *) message;
2062 c = connection_get (&msg->cid);
2066 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2068 LOG (GNUNET_ERROR_TYPE_DEBUG,
2069 "WARNING POLL message on unknown connection %s!\n",
2070 GNUNET_h2s (&msg->cid));
2074 /* Is this a forward or backward ACK?
2075 * Note: a poll should never be needed in a loopback case,
2076 * since there is no possiblility of packet loss there, so
2077 * this way of discerining FWD/BCK should not be a problem.
2079 id = GNUNET_PEER_search (peer);
2080 if (GMP_get_short_id (get_next_hop (c)) == id)
2082 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2085 else if (GMP_get_short_id (get_prev_hop (c)) == id)
2087 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2092 GNUNET_break_op (0);
2096 pid = ntohl (msg->pid);
2097 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2098 fc->last_pid_recv = pid;
2099 fwd = fc == &c->bck_fc;
2100 GMC_send_ack (c, fwd, GNUNET_YES);
2107 * Core handler for mesh keepalives.
2109 * @param cls closure
2110 * @param message message
2111 * @param peer peer identity this notification is about
2112 * @return GNUNET_OK to keep the connection open,
2113 * GNUNET_SYSERR to close it (signal serious error)
2115 * TODO: Check who we got this from, to validate route.
2118 GMC_handle_keepalive (void *cls, const struct GNUNET_PeerIdentity *peer,
2119 const struct GNUNET_MessageHeader *message)
2121 struct GNUNET_MESH_ConnectionKeepAlive *msg;
2122 struct MeshConnection *c;
2123 struct MeshPeer *neighbor;
2124 GNUNET_PEER_Id peer_id;
2127 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) message;
2128 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a keepalive packet from %s\n",
2131 c = connection_get (&msg->cid);
2134 GNUNET_STATISTICS_update (stats, "# keepalive on unknown connection", 1,
2139 /* Check if origin is as expected TODO refactor and reuse */
2140 peer_id = GNUNET_PEER_search (peer);
2141 neighbor = get_prev_hop (c);
2142 if (peer_id == GMP_get_short_id (neighbor))
2148 neighbor = get_next_hop (c);
2149 if (peer_id == GMP_get_short_id (neighbor))
2155 GNUNET_break_op (0);
2160 connection_change_state (c, MESH_CONNECTION_READY);
2161 connection_reset_timeout (c, fwd);
2163 if (GMC_is_terminal (c, fwd))
2166 GNUNET_STATISTICS_update (stats, "# keepalives forwarded", 1, GNUNET_NO);
2167 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
2174 * Send an ACK on the appropriate connection/channel, depending on
2175 * the direction and the position of the peer.
2177 * @param c Which connection to send the hop-by-hop ACK.
2178 * @param fwd Is this a fwd ACK? (will go dest->root).
2179 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2182 GMC_send_ack (struct MeshConnection *c, int fwd, int force)
2184 unsigned int buffer;
2186 LOG (GNUNET_ERROR_TYPE_DEBUG,
2187 "GMC send %s ACK on %s\n",
2188 GM_f2s (fwd), GMC_2s (c));
2196 if (GNUNET_NO != c->destroy)
2198 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2202 /* Get available buffer space */
2203 if (GMC_is_terminal (c, fwd))
2205 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2206 buffer = GMT_get_channels_buffer (c->t);
2210 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2211 buffer = GMC_get_buffer (c, fwd);
2213 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2214 if (0 == buffer && GNUNET_NO == force)
2217 /* Send available buffer space */
2218 if (GMC_is_origin (c, fwd))
2220 GNUNET_assert (NULL != c->t);
2221 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2222 GMT_unchoke_channels (c->t);
2226 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2227 send_ack (c, buffer, fwd, force);
2233 * Initialize the connections subsystem
2235 * @param c Configuration handle.
2238 GMC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2240 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2242 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_MSGS_QUEUE",
2245 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2246 "MESH", "MAX_MSGS_QUEUE", "MISSING");
2247 GNUNET_SCHEDULER_shutdown ();
2252 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_CONNECTIONS",
2255 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2256 "MESH", "MAX_CONNECTIONS", "MISSING");
2257 GNUNET_SCHEDULER_shutdown ();
2262 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REFRESH_CONNECTION_TIME",
2263 &refresh_connection_time))
2265 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2266 "MESH", "REFRESH_CONNECTION_TIME", "MISSING");
2267 GNUNET_SCHEDULER_shutdown ();
2270 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2271 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_YES);
2276 * Destroy each connection on shutdown.
2278 * @param cls Closure (unused).
2279 * @param key Current key code (CID, unused).
2280 * @param value Value in the hash map (connection)
2282 * @return #GNUNET_YES, because we should continue to iterate,
2285 shutdown_iterator (void *cls,
2286 const struct GNUNET_HashCode *key,
2289 struct MeshConnection *c = value;
2297 * Shut down the connections subsystem.
2302 GNUNET_CONTAINER_multihashmap_iterate (connections, &shutdown_iterator, NULL);
2303 GNUNET_CONTAINER_multihashmap_destroy (connections);
2308 struct MeshConnection *
2309 GMC_new (const struct GNUNET_HashCode *cid,
2310 struct MeshTunnel3 *t,
2311 struct MeshPeerPath *p,
2312 unsigned int own_pos)
2314 struct MeshConnection *c;
2316 c = GNUNET_new (struct MeshConnection);
2318 GNUNET_assert (GNUNET_OK ==
2319 GNUNET_CONTAINER_multihashmap_put (connections,
2321 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2322 fc_init (&c->fwd_fc);
2323 fc_init (&c->bck_fc);
2328 GNUNET_assert (own_pos <= p->length - 1);
2329 c->own_pos = own_pos;
2332 if (GNUNET_OK != register_neighbors (c))
2336 path_invalidate (c->path);
2346 c->fwd_maintenance_task =
2347 GNUNET_SCHEDULER_add_delayed (create_connection_time,
2348 &connection_fwd_keepalive, c);
2356 GMC_destroy (struct MeshConnection *c)
2364 if (2 == c->destroy) /* cancel queues -> GMP_queue_cancel -> q_destroy -> */
2365 return; /* -> message_sent -> GMC_destroy. Don't loop. */
2368 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying connection %s\n", GMC_2s (c));
2369 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc's f: %p, b: %p\n",
2370 &c->fwd_fc, &c->bck_fc);
2371 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2372 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2374 /* Cancel all traffic */
2375 if (NULL != c->path)
2377 connection_cancel_queues (c, GNUNET_YES);
2378 connection_cancel_queues (c, GNUNET_NO);
2379 unregister_neighbors (c);
2382 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2383 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2385 /* Cancel maintainance task (keepalive/timeout) */
2386 if (NULL != c->fwd_fc.poll_msg)
2388 GMC_cancel (c->fwd_fc.poll_msg);
2389 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg FWD canceled\n");
2391 if (NULL != c->bck_fc.poll_msg)
2393 GMC_cancel (c->bck_fc.poll_msg);
2394 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg BCK canceled\n");
2397 /* Delete from tunnel */
2399 GMT_remove_connection (c->t, c);
2401 if (GNUNET_NO == GMC_is_origin (c, GNUNET_YES) && NULL != c->path)
2402 path_destroy (c->path);
2403 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_maintenance_task)
2404 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2405 if (GNUNET_SCHEDULER_NO_TASK != c->bck_maintenance_task)
2406 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2407 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_fc.poll_task)
2409 GNUNET_SCHEDULER_cancel (c->fwd_fc.poll_task);
2410 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL FWD canceled\n");
2412 if (GNUNET_SCHEDULER_NO_TASK != c->bck_fc.poll_task)
2414 GNUNET_SCHEDULER_cancel (c->bck_fc.poll_task);
2415 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL BCK canceled\n");
2418 GNUNET_break (GNUNET_YES ==
2419 GNUNET_CONTAINER_multihashmap_remove (connections, &c->id, c));
2421 GNUNET_STATISTICS_update (stats, "# connections", -1, GNUNET_NO);
2426 * Get the connection ID.
2428 * @param c Connection to get the ID from.
2430 * @return ID of the connection.
2432 const struct GNUNET_HashCode *
2433 GMC_get_id (const struct MeshConnection *c)
2440 * Get the connection path.
2442 * @param c Connection to get the path from.
2444 * @return path used by the connection.
2446 const struct MeshPeerPath *
2447 GMC_get_path (const struct MeshConnection *c)
2449 if (GNUNET_NO == c->destroy)
2456 * Get the connection state.
2458 * @param c Connection to get the state from.
2460 * @return state of the connection.
2462 enum MeshConnectionState
2463 GMC_get_state (const struct MeshConnection *c)
2469 * Get the connection tunnel.
2471 * @param c Connection to get the tunnel from.
2473 * @return tunnel of the connection.
2475 struct MeshTunnel3 *
2476 GMC_get_tunnel (const struct MeshConnection *c)
2483 * Get free buffer space in a connection.
2485 * @param c Connection.
2486 * @param fwd Is query about FWD traffic?
2488 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2491 GMC_get_buffer (struct MeshConnection *c, int fwd)
2493 struct MeshFlowControl *fc;
2495 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2497 return (fc->queue_max - fc->queue_n);
2501 * Get how many messages have we allowed to send to us from a direction.
2503 * @param c Connection.
2504 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2506 * @return last_ack_sent - last_pid_recv
2509 GMC_get_allowed (struct MeshConnection *c, int fwd)
2511 struct MeshFlowControl *fc;
2513 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2514 if (GM_is_pid_bigger(fc->last_pid_recv, fc->last_ack_sent))
2518 return (fc->last_ack_sent - fc->last_pid_recv);
2522 * Get messages queued in a connection.
2524 * @param c Connection.
2525 * @param fwd Is query about FWD traffic?
2527 * @return Number of messages queued.
2530 GMC_get_qn (struct MeshConnection *c, int fwd)
2532 struct MeshFlowControl *fc;
2534 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2541 * Allow the connection to advertise a buffer of the given size.
2543 * The connection will send an @c fwd ACK message (so: in direction !fwd)
2544 * allowing up to last_pid_recv + buffer.
2546 * @param c Connection.
2547 * @param buffer How many more messages the connection can accept.
2548 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
2551 GMC_allow (struct MeshConnection *c, unsigned int buffer, int fwd)
2553 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
2554 GMC_2s (c), buffer, GM_f2s (fwd));
2555 send_ack (c, buffer, fwd, GNUNET_NO);
2560 * Notify other peers on a connection of a broken link. Mark connections
2561 * to destroy after all traffic has been sent.
2563 * @param c Connection on which there has been a disconnection.
2564 * @param peer Peer that disconnected.
2567 GMC_notify_broken (struct MeshConnection *c,
2568 struct MeshPeer *peer)
2572 LOG (GNUNET_ERROR_TYPE_DEBUG,
2573 " notify broken on %s due to %s disconnect\n",
2574 GMC_2s (c), GMP_2s (peer));
2576 fwd = peer == get_prev_hop (c);
2578 if (GNUNET_YES == GMC_is_terminal (c, fwd))
2580 /* Local shutdown, no one to notify about this. */
2584 if (GNUNET_NO == c->destroy)
2585 send_broken (c, &my_full_id, GMP_get_id (peer), fwd);
2587 /* Connection will have at least one pending message
2588 * (the one we just scheduled), so no point in checking whether to
2589 * destroy immediately. */
2590 c->destroy = GNUNET_YES;
2591 c->state = MESH_CONNECTION_DESTROYED;
2594 * Cancel all queues, if no message is left, connection will be destroyed.
2596 connection_cancel_queues (c, !fwd);
2603 * Is this peer the first one on the connection?
2605 * @param c Connection.
2606 * @param fwd Is this about fwd traffic?
2608 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
2611 GMC_is_origin (struct MeshConnection *c, int fwd)
2613 if (!fwd && c->path->length - 1 == c->own_pos )
2615 if (fwd && 0 == c->own_pos)
2622 * Is this peer the last one on the connection?
2624 * @param c Connection.
2625 * @param fwd Is this about fwd traffic?
2626 * Note that the ROOT is the terminal for BCK traffic!
2628 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
2631 GMC_is_terminal (struct MeshConnection *c, int fwd)
2633 return GMC_is_origin (c, !fwd);
2638 * See if we are allowed to send by the next hop in the given direction.
2640 * @param c Connection.
2641 * @param fwd Is this about fwd traffic?
2643 * @return #GNUNET_YES in case it's OK to send.
2646 GMC_is_sendable (struct MeshConnection *c, int fwd)
2648 struct MeshFlowControl *fc;
2650 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2651 if (GM_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2657 * Sends an already built message on a connection, properly registering
2658 * all used resources.
2660 * @param message Message to send. Function makes a copy of it.
2661 * If message is not hop-by-hop, decrements TTL of copy.
2662 * @param c Connection on which this message is transmitted.
2663 * @param fwd Is this a fwd message?
2664 * @param force Force the connection to accept the message (buffer overfill).
2665 * @param cont Continuation called once message is sent. Can be NULL.
2666 * @param cont_cls Closure for @c cont.
2668 * @return Handle to cancel the message before it's sent.
2669 * NULL on error or if @c cont is NULL.
2670 * Invalid on @c cont call.
2672 struct MeshConnectionQueue *
2673 GMC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2674 struct MeshConnection *c, int fwd, int force,
2675 GMC_sent cont, void *cont_cls)
2677 struct MeshFlowControl *fc;
2678 struct MeshConnectionQueue *q;
2684 size = ntohs (message->size);
2685 data = GNUNET_malloc (size);
2686 memcpy (data, message, size);
2687 type = ntohs (message->type);
2688 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send %s (%u bytes) on connection %s\n",
2689 GM_m2s (type), size, GMC_2s (c));
2691 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2692 droppable = GNUNET_NO == force;
2695 struct GNUNET_MESH_Encrypted *emsg;
2696 struct GNUNET_MESH_KX *kmsg;
2697 struct GNUNET_MESH_ACK *amsg;
2698 struct GNUNET_MESH_Poll *pmsg;
2699 struct GNUNET_MESH_ConnectionDestroy *dmsg;
2700 struct GNUNET_MESH_ConnectionBroken *bmsg;
2703 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
2704 emsg = (struct GNUNET_MESH_Encrypted *) data;
2705 ttl = ntohl (emsg->ttl);
2708 GNUNET_break_op (0);
2713 emsg->ttl = htonl (ttl - 1);
2714 emsg->pid = htonl (fc->next_pid++);
2715 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
2716 if (GNUNET_YES == droppable)
2719 LOG (GNUNET_ERROR_TYPE_DEBUG, "pid %u\n", ntohl (emsg->pid));
2720 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
2721 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
2725 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
2727 if (GM_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
2729 GMC_start_poll (c, fwd);
2733 case GNUNET_MESSAGE_TYPE_MESH_KX:
2734 kmsg = (struct GNUNET_MESH_KX *) data;
2738 case GNUNET_MESSAGE_TYPE_MESH_ACK:
2739 amsg = (struct GNUNET_MESH_ACK *) data;
2741 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
2742 droppable = GNUNET_NO;
2745 case GNUNET_MESSAGE_TYPE_MESH_POLL:
2746 pmsg = (struct GNUNET_MESH_Poll *) data;
2748 LOG (GNUNET_ERROR_TYPE_DEBUG, " poll %u\n", ntohl (pmsg->pid));
2749 droppable = GNUNET_NO;
2752 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY:
2753 dmsg = (struct GNUNET_MESH_ConnectionDestroy *) data;
2758 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN:
2759 bmsg = (struct GNUNET_MESH_ConnectionBroken *) data;
2764 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE:
2765 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK:
2766 case GNUNET_MESSAGE_TYPE_MESH_KEEPALIVE:
2775 if (fc->queue_n > fc->queue_max && droppable)
2777 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
2780 LOG (GNUNET_ERROR_TYPE_DEBUG,
2781 "queue full: %u/%u\n",
2782 fc->queue_n, fc->queue_max);
2783 if (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED == type)
2789 return NULL; /* Drop this message */
2792 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u\n", c, c->pending_messages);
2793 c->pending_messages++;
2795 q = GNUNET_new (struct MeshConnectionQueue);
2796 q->forced = !droppable;
2797 q->q = GMP_queue_add (get_hop (c, fwd), data, type, size, c, fwd,
2801 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING dropping msg on %s\n", GMC_2s (c));
2807 q->cont_cls = cont_cls;
2813 * Cancel a previously sent message while it's in the queue.
2815 * ONLY can be called before the continuation given to the send function
2816 * is called. Once the continuation is called, the message is no longer in the
2819 * @param q Handle to the queue.
2822 GMC_cancel (struct MeshConnectionQueue *q)
2824 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GMC cancel message\n");
2826 /* queue destroy calls message_sent, which calls q->cont and frees q */
2827 GMP_queue_destroy (q->q, GNUNET_YES);
2832 * Sends a CREATE CONNECTION message for a path to a peer.
2833 * Changes the connection and tunnel states if necessary.
2835 * @param connection Connection to create.
2838 GMC_send_create (struct MeshConnection *connection)
2840 enum MeshTunnel3CState state;
2843 size = sizeof (struct GNUNET_MESH_ConnectionCreate);
2844 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
2846 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection create\n");
2847 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
2848 connection, connection->pending_messages);
2849 connection->pending_messages++;
2851 GMP_queue_add (get_next_hop (connection), NULL,
2852 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE,
2853 size, connection, GNUNET_YES, &message_sent, NULL);
2855 state = GMT_get_cstate (connection->t);
2856 if (MESH_TUNNEL3_SEARCHING == state || MESH_TUNNEL3_NEW == state)
2857 GMT_change_cstate (connection->t, MESH_TUNNEL3_WAITING);
2858 if (MESH_CONNECTION_NEW == connection->state)
2859 connection_change_state (connection, MESH_CONNECTION_SENT);
2864 * Send a message to all peers in this connection that the connection
2865 * is no longer valid.
2867 * If some peer should not receive the message, it should be zero'ed out
2868 * before calling this function.
2870 * @param c The connection whose peers to notify.
2873 GMC_send_destroy (struct MeshConnection *c)
2875 struct GNUNET_MESH_ConnectionDestroy msg;
2877 if (GNUNET_YES == c->destroy)
2880 msg.header.size = htons (sizeof (msg));
2881 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY);;
2883 LOG (GNUNET_ERROR_TYPE_DEBUG,
2884 " sending connection destroy for connection %s\n",
2887 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_YES))
2888 GMC_send_prebuilt_message (&msg.header, c,
2889 GNUNET_YES, GNUNET_YES, NULL, NULL);
2890 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_NO))
2891 GMC_send_prebuilt_message (&msg.header, c,
2892 GNUNET_NO, GNUNET_YES, NULL, NULL);
2893 c->destroy = GNUNET_YES;
2894 c->state = MESH_CONNECTION_DESTROYED;
2899 * @brief Start a polling timer for the connection.
2901 * When a neighbor does not accept more traffic on the connection it could be
2902 * caused by a simple congestion or by a lost ACK. Polling enables to check
2903 * for the lastest ACK status for a connection.
2905 * @param c Connection.
2906 * @param fwd Should we poll in the FWD direction?
2909 GMC_start_poll (struct MeshConnection *c, int fwd)
2911 struct MeshFlowControl *fc;
2913 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2914 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL %s requested\n",
2916 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task || NULL != fc->poll_msg)
2918 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** not needed (%u, %p)\n",
2919 fc->poll_task, fc->poll_msg);
2922 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL started on request\n");
2923 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
2930 * @brief Stop polling a connection for ACKs.
2932 * Once we have enough ACKs for future traffic, polls are no longer necessary.
2934 * @param c Connection.
2935 * @param fwd Should we stop the poll in the FWD direction?
2938 GMC_stop_poll (struct MeshConnection *c, int fwd)
2940 struct MeshFlowControl *fc;
2942 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2943 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
2945 GNUNET_SCHEDULER_cancel (fc->poll_task);
2946 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2951 * Get a (static) string for a connection.
2953 * @param c Connection.
2956 GMC_2s (const struct MeshConnection *c)
2963 static char buf[128];
2965 sprintf (buf, "%s (->%s)", GNUNET_h2s (&c->id), GMT_2s (c->t));
2968 return GNUNET_h2s (&c->id);