2 This file is part of GNUnet.
3 (C) 2001-2013 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file mesh/gnunet-service-mesh_connection.c
23 * @brief GNUnet MESH service connection handling
24 * @author Bartlomiej Polot
28 #include "gnunet_util_lib.h"
30 #include "gnunet_statistics_service.h"
32 #include "mesh_path.h"
33 #include "mesh_protocol.h"
35 #include "gnunet-service-mesh_connection.h"
36 #include "gnunet-service-mesh_peer.h"
37 #include "gnunet-service-mesh_tunnel.h"
40 #define LOG(level, ...) GNUNET_log_from (level,"mesh-con",__VA_ARGS__)
42 #define MESH_MAX_POLL_TIME GNUNET_TIME_relative_multiply (\
43 GNUNET_TIME_UNIT_MINUTES,\
48 /******************************************************************************/
49 /******************************** STRUCTS **********************************/
50 /******************************************************************************/
53 * Struct to encapsulate all the Flow Control information to a peer to which
54 * we are directly connected (on a core level).
56 struct MeshFlowControl
59 * Connection this controls.
61 struct MeshConnection *c;
64 * How many messages are in the queue on this connection.
69 * How many messages do we accept in the queue.
71 unsigned int queue_max;
79 * ID of the last packet sent towards the peer.
81 uint32_t last_pid_sent;
84 * ID of the last packet received from the peer.
86 uint32_t last_pid_recv;
89 * Last ACK sent to the peer (peer can't send more than this PID).
91 uint32_t last_ack_sent;
94 * Last ACK sent towards the origin (for traffic towards leaf node).
96 uint32_t last_ack_recv;
99 * Task to poll the peer in case of a lost ACK causes stall.
101 GNUNET_SCHEDULER_TaskIdentifier poll_task;
104 * How frequently to poll for ACKs.
106 struct GNUNET_TIME_Relative poll_time;
109 * Queued poll message, to cancel if not necessary anymore (got ACK).
111 struct MeshConnectionQueue *poll_msg;
114 * Queued poll message, to cancel if not necessary anymore (got ACK).
116 struct MeshConnectionQueue *ack_msg;
120 * Keep a record of the last messages sent on this connection.
122 struct MeshConnectionPerformance
125 * Circular buffer for storing measurements.
127 double usecsperbyte[AVG_MSGS];
130 * Running average of @c usecsperbyte.
135 * How many values of @c usecsperbyte are valid.
140 * Index of the next "free" position in @c usecsperbyte.
147 * Struct containing all information regarding a connection to a peer.
149 struct MeshConnection
152 * Tunnel this connection is part of.
154 struct MeshTunnel3 *t;
157 * Flow control information for traffic fwd.
159 struct MeshFlowControl fwd_fc;
162 * Flow control information for traffic bck.
164 struct MeshFlowControl bck_fc;
167 * Measure connection performance on the endpoint.
169 struct MeshConnectionPerformance *perf;
172 * ID of the connection.
174 struct GNUNET_HashCode id;
177 * State of the connection.
179 enum MeshConnectionState state;
182 * Path being used for the tunnel. 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 a notification that a connection is broken, when a connection
795 * isn't even created.
797 * @param connection_id Connection ID.
798 * @param id1 Peer that has disconnected.
799 * @param id2 Peer that has disconnected.
800 * @param peer Peer to notify (neighbor who sent the connection).
803 send_broken2 (struct GNUNET_HashCode *connection_id,
804 const struct GNUNET_PeerIdentity *id1,
805 const struct GNUNET_PeerIdentity *id2,
806 GNUNET_PEER_Id peer_id)
808 struct GNUNET_MESH_ConnectionBroken *msg;
809 struct MeshPeer *neighbor;
811 msg = GNUNET_new (struct GNUNET_MESH_ConnectionBroken);
812 msg->header.size = htons (sizeof (struct GNUNET_MESH_ConnectionBroken));
813 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN);
814 msg->cid = *connection_id;
817 neighbor = GMP_get_short (peer_id);
818 GMP_queue_add (neighbor, msg,
819 GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED,
820 sizeof (struct GNUNET_MESH_ConnectionBroken),
821 NULL, GNUNET_SYSERR, /* connection, fwd */
822 NULL, NULL); /* continuation */
827 * Send keepalive packets for a connection.
829 * @param c Connection to keep alive..
830 * @param fwd Is this a FWD keepalive? (owner -> dest).
833 connection_keepalive (struct MeshConnection *c, int fwd)
835 struct GNUNET_MESH_ConnectionKeepAlive *msg;
836 size_t size = sizeof (struct GNUNET_MESH_ConnectionKeepAlive);
839 LOG (GNUNET_ERROR_TYPE_DEBUG,
840 "sending %s keepalive for connection %s]\n",
841 GM_f2s (fwd), GMC_2s (c));
843 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) cbuf;
844 msg->header.size = htons (size);
845 msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_KEEPALIVE);
847 msg->reserved = htonl (0);
849 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_YES, NULL, NULL);
854 * Send CONNECTION_{CREATE/ACK} packets for a connection.
856 * @param c Connection for which to send the message.
857 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
860 connection_recreate (struct MeshConnection *c, int fwd)
862 LOG (GNUNET_ERROR_TYPE_DEBUG, "sending connection recreate\n");
866 send_connection_ack (c, GNUNET_NO);
871 * Generic connection timer management.
872 * Depending on the role of the peer in the connection will send the
873 * appropriate message (build or keepalive)
875 * @param c Conncetion to maintain.
879 connection_maintain (struct MeshConnection *c, int fwd)
881 if (GNUNET_NO != c->destroy)
884 if (MESH_TUNNEL3_SEARCHING == GMT_get_cstate (c->t))
886 /* TODO DHT GET with RO_BART */
891 case MESH_CONNECTION_NEW:
894 case MESH_CONNECTION_SENT:
895 connection_recreate (c, fwd);
897 case MESH_CONNECTION_READY:
898 connection_keepalive (c, fwd);
907 connection_fwd_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
909 struct MeshConnection *c = cls;
910 struct GNUNET_TIME_Relative delay;
912 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
913 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
916 connection_maintain (c, GNUNET_YES);
917 delay = c->state == MESH_CONNECTION_READY ?
918 refresh_connection_time : create_connection_time;
919 c->fwd_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
920 &connection_fwd_keepalive,
926 connection_bck_keepalive (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
928 struct MeshConnection *c = cls;
929 struct GNUNET_TIME_Relative delay;
931 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
932 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
935 connection_maintain (c, GNUNET_NO);
936 delay = c->state == MESH_CONNECTION_READY ?
937 refresh_connection_time : create_connection_time;
938 c->bck_maintenance_task = GNUNET_SCHEDULER_add_delayed (delay,
939 &connection_bck_keepalive,
945 * @brief Re-initiate traffic on this connection if necessary.
947 * Check if there is traffic queued towards this peer
948 * and the core transmit handle is NULL (traffic was stalled).
949 * If so, call core tmt rdy.
951 * @param c Connection on which initiate traffic.
952 * @param fwd Is this about fwd traffic?
955 connection_unlock_queue (struct MeshConnection *c, int fwd)
957 struct MeshPeer *peer;
959 LOG (GNUNET_ERROR_TYPE_DEBUG,
960 "connection_unlock_queue %s on %s\n",
961 GM_f2s (fwd), GMC_2s (c));
963 if (GMC_is_terminal (c, fwd))
965 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal!\n");
969 peer = get_hop (c, fwd);
970 GMP_queue_unlock (peer, c);
975 * Cancel all transmissions that belong to a certain connection.
977 * If the connection is scheduled for destruction and no more messages are left,
978 * the connection will be destroyed by the continuation call.
980 * @param c Connection which to cancel. Might be destroyed during this call.
981 * @param fwd Cancel fwd traffic?
984 connection_cancel_queues (struct MeshConnection *c, int fwd)
986 struct MeshFlowControl *fc;
987 struct MeshPeer *peer;
989 LOG (GNUNET_ERROR_TYPE_DEBUG,
990 " *** Cancel %s queues for connection %s\n",
991 GM_f2s (fwd), GMC_2s (c));
998 fc = fwd ? &c->fwd_fc : &c->bck_fc;
999 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
1001 GNUNET_SCHEDULER_cancel (fc->poll_task);
1002 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1003 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Cancel POLL in ccq for fc %p\n", fc);
1005 peer = get_hop (c, fwd);
1006 GMP_queue_cancel (peer, c);
1011 * Function called if a connection has been stalled for a while,
1012 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1014 * @param cls Closure (poll ctx).
1015 * @param tc TaskContext.
1018 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
1022 * Callback called when a queued POLL message is sent.
1024 * @param cls Closure (FC).
1025 * @param c Connection this message was on.
1026 * @param q Queue handler this call invalidates.
1027 * @param type Type of message sent.
1028 * @param fwd Was this a FWD going message?
1029 * @param size Size of the message.
1032 poll_sent (void *cls,
1033 struct MeshConnection *c,
1034 struct MeshConnectionQueue *q,
1035 uint16_t type, int fwd, size_t size)
1037 struct MeshFlowControl *fc = cls;
1039 if (2 == c->destroy)
1041 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL canceled on shutdown\n");
1044 LOG (GNUNET_ERROR_TYPE_DEBUG,
1045 " *** POLL sent for , scheduling new one!\n");
1046 fc->poll_msg = NULL;
1047 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1048 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1049 &connection_poll, fc);
1050 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1055 * Function called if a connection has been stalled for a while,
1056 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1058 * @param cls Closure (poll ctx).
1059 * @param tc TaskContext.
1062 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1064 struct MeshFlowControl *fc = cls;
1065 struct GNUNET_MESH_Poll msg;
1066 struct MeshConnection *c;
1068 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1069 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1075 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Polling!\n");
1076 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** connection [%s]\n", GMC_2s (c));
1077 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** %s\n",
1078 fc == &c->fwd_fc ? "FWD" : "BCK");
1080 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_POLL);
1081 msg.header.size = htons (sizeof (msg));
1082 msg.pid = htonl (fc->last_pid_sent);
1083 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** last pid sent: %u!\n", fc->last_pid_sent);
1084 fc->poll_msg = GMC_send_prebuilt_message (&msg.header, c,
1085 fc == &c->fwd_fc, GNUNET_YES,
1091 * Timeout function due to lack of keepalive/traffic from the owner.
1092 * Destroys connection if called.
1094 * @param cls Closure (connection to destroy).
1095 * @param tc TaskContext.
1098 connection_fwd_timeout (void *cls,
1099 const struct GNUNET_SCHEDULER_TaskContext *tc)
1101 struct MeshConnection *c = cls;
1103 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1104 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1107 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s FWD timed out. Destroying.\n",
1109 if (GMC_is_origin (c, GNUNET_YES)) /* If local, leave. */
1120 * Timeout function due to lack of keepalive/traffic from the destination.
1121 * Destroys connection if called.
1123 * @param cls Closure (connection to destroy).
1124 * @param tc TaskContext
1127 connection_bck_timeout (void *cls,
1128 const struct GNUNET_SCHEDULER_TaskContext *tc)
1130 struct MeshConnection *c = cls;
1132 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1133 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1136 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s BCK timed out. Destroying.\n",
1139 if (GMC_is_origin (c, GNUNET_NO)) /* If local, leave. */
1150 * Resets the connection timeout task, some other message has done the
1152 * - For the first peer on the direction this means to send
1153 * a keepalive or a path confirmation message (either create or ACK).
1154 * - For all other peers, this means to destroy the connection,
1155 * due to lack of activity.
1156 * Starts the timeout if no timeout was running (connection just created).
1158 * @param c Connection whose timeout to reset.
1159 * @param fwd Is this forward?
1161 * TODO use heap to improve efficiency of scheduler.
1164 connection_reset_timeout (struct MeshConnection *c, int fwd)
1166 GNUNET_SCHEDULER_TaskIdentifier *ti;
1167 GNUNET_SCHEDULER_Task f;
1169 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1171 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GM_f2s (fwd));
1173 if (GNUNET_SCHEDULER_NO_TASK != *ti)
1174 GNUNET_SCHEDULER_cancel (*ti);
1176 if (GMC_is_origin (c, fwd)) /* Startpoint */
1178 f = fwd ? &connection_fwd_keepalive : &connection_bck_keepalive;
1179 *ti = GNUNET_SCHEDULER_add_delayed (refresh_connection_time, f, c);
1181 else /* Relay, endpoint. */
1183 struct GNUNET_TIME_Relative delay;
1185 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1186 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1187 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1193 * Add the connection to the list of both neighbors.
1195 * @param c Connection.
1197 * @return #GNUNET_OK if everything went fine
1198 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1201 register_neighbors (struct MeshConnection *c)
1203 struct MeshPeer *next_peer;
1204 struct MeshPeer *prev_peer;
1206 next_peer = get_next_hop (c);
1207 prev_peer = get_prev_hop (c);
1209 LOG (GNUNET_ERROR_TYPE_DEBUG, "register neighbors for connection %s\n",
1211 path_debug (c->path);
1212 LOG (GNUNET_ERROR_TYPE_DEBUG, "own pos %u\n", c->own_pos);
1213 LOG (GNUNET_ERROR_TYPE_DEBUG, "putting connection %s to next peer %p\n",
1214 GMC_2s (c), next_peer);
1215 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n", next_peer, GMP_2s (next_peer));
1216 LOG (GNUNET_ERROR_TYPE_DEBUG, "putting connection %s to prev peer %p\n",
1217 GMC_2s (c), prev_peer);
1218 LOG (GNUNET_ERROR_TYPE_DEBUG, "prev peer %p %s\n", prev_peer, GMP_2s (prev_peer));
1220 if (GNUNET_NO == GMP_is_neighbor (next_peer)
1221 || GNUNET_NO == GMP_is_neighbor (prev_peer))
1223 if (GMC_is_origin (c, GNUNET_YES))
1224 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1225 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1227 LOG (GNUNET_ERROR_TYPE_DEBUG, " register neighbors failed\n");
1228 LOG (GNUNET_ERROR_TYPE_DEBUG, " prev: %s, neighbor?: %d\n",
1229 GMP_2s (prev_peer), GMP_is_neighbor (prev_peer));
1230 LOG (GNUNET_ERROR_TYPE_DEBUG, " next: %s, neighbor?: %d\n",
1231 GMP_2s (next_peer), GMP_is_neighbor (next_peer));
1232 return GNUNET_SYSERR;
1235 GMP_add_connection (next_peer, c);
1236 GMP_add_connection (prev_peer, c);
1243 * Remove the connection from the list of both neighbors.
1245 * @param c Connection.
1248 unregister_neighbors (struct MeshConnection *c)
1250 struct MeshPeer *peer;
1252 peer = get_next_hop (c);
1253 if (GNUNET_OK != GMP_remove_connection (peer, c))
1255 GNUNET_assert (MESH_CONNECTION_NEW == c->state
1256 || MESH_CONNECTION_DESTROYED == c->state);
1257 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate: %u\n", c->state);
1258 if (NULL != c->t) GMT_debug (c->t);
1261 peer = get_prev_hop (c);
1262 if (GNUNET_OK != GMP_remove_connection (peer, c))
1264 GNUNET_assert (MESH_CONNECTION_NEW == c->state
1265 || MESH_CONNECTION_DESTROYED == c->state);
1266 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate: %u\n", c->state);
1267 if (NULL != c->t) GMT_debug (c->t);
1273 * Bind the connection to the peer and the tunnel to that peer.
1275 * If the peer has no tunnel, create one. Update tunnel and connection
1276 * data structres to reflect new status.
1278 * @param c Connection.
1282 add_to_peer (struct MeshConnection *c, struct MeshPeer *peer)
1284 GMP_add_tunnel (peer);
1285 c->t = GMP_get_tunnel (peer);
1286 GMT_add_connection (c->t, c);
1291 * Builds a path from a PeerIdentity array.
1293 * @param peers PeerIdentity array.
1294 * @param size Size of the @c peers array.
1295 * @param own_pos Output parameter: own position in the path.
1297 * @return Fixed and shortened path.
1299 static struct MeshPeerPath *
1300 build_path_from_peer_ids (struct GNUNET_PeerIdentity *peers,
1302 unsigned int *own_pos)
1304 struct MeshPeerPath *path;
1305 GNUNET_PEER_Id shortid;
1308 unsigned int offset;
1311 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating path...\n");
1312 path = path_new (size);
1315 for (i = 0; i < size; i++)
1317 LOG (GNUNET_ERROR_TYPE_DEBUG, " - %u: taking %s\n",
1318 i, GNUNET_i2s (&peers[i]));
1319 shortid = GNUNET_PEER_intern (&peers[i]);
1321 /* Check for loops / duplicates */
1322 for (j = 0; j < i - offset; j++)
1324 if (path->peers[j] == shortid)
1326 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists at pos %u\n", j);
1328 LOG (GNUNET_ERROR_TYPE_DEBUG, " offset now\n", offset);
1329 GNUNET_PEER_change_rc (shortid, -1);
1332 LOG (GNUNET_ERROR_TYPE_DEBUG, " storing at %u\n", i - offset);
1333 path->peers[i - offset] = shortid;
1334 if (path->peers[i] == myid)
1337 path->length -= offset;
1339 if (path->peers[*own_pos] != myid)
1341 /* create path: self not found in path through self */
1342 GNUNET_break_op (0);
1343 path_destroy (path);
1350 /******************************************************************************/
1351 /******************************** API ***********************************/
1352 /******************************************************************************/
1355 * Core handler for connection creation.
1357 * @param cls Closure (unused).
1358 * @param peer Sender (neighbor).
1359 * @param message Message.
1361 * @return GNUNET_OK to keep the connection open,
1362 * GNUNET_SYSERR to close it (signal serious error)
1365 GMC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
1366 const struct GNUNET_MessageHeader *message)
1368 struct GNUNET_MESH_ConnectionCreate *msg;
1369 struct GNUNET_PeerIdentity *id;
1370 struct GNUNET_HashCode *cid;
1371 struct MeshPeerPath *path;
1372 struct MeshPeer *dest_peer;
1373 struct MeshPeer *orig_peer;
1374 struct MeshConnection *c;
1375 unsigned int own_pos;
1378 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1379 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection create msg\n");
1382 size = ntohs (message->size);
1383 if (size < sizeof (struct GNUNET_MESH_ConnectionCreate))
1385 GNUNET_break_op (0);
1389 /* Calculate hops */
1390 size -= sizeof (struct GNUNET_MESH_ConnectionCreate);
1391 if (size % sizeof (struct GNUNET_PeerIdentity))
1393 GNUNET_break_op (0);
1396 size /= sizeof (struct GNUNET_PeerIdentity);
1399 GNUNET_break_op (0);
1402 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1404 /* Get parameters */
1405 msg = (struct GNUNET_MESH_ConnectionCreate *) message;
1407 id = (struct GNUNET_PeerIdentity *) &msg[1];
1408 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s (%s->).\n",
1409 GNUNET_h2s (cid), GNUNET_i2s (id));
1411 /* Create connection */
1412 c = connection_get (cid);
1415 path = build_path_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
1421 GNUNET_break_op (0);
1424 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1425 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1426 c = GMC_new (cid, NULL, path_duplicate (path), own_pos);
1429 if (path->length - 1 == own_pos)
1431 /* If we are destination, why did the creation fail? */
1435 send_broken2 (cid, &my_full_id,
1436 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
1437 path->peers[own_pos - 1]);
1438 path_destroy (path);
1441 GMP_add_path_to_all (path, GNUNET_NO);
1442 connection_reset_timeout (c, GNUNET_YES);
1446 path = path_duplicate (c->path);
1448 if (MESH_CONNECTION_NEW == c->state)
1449 connection_change_state (c, MESH_CONNECTION_SENT);
1451 /* Remember peers */
1452 dest_peer = GMP_get (&id[size - 1]);
1453 orig_peer = GMP_get (&id[0]);
1455 /* Is it a connection to us? */
1456 if (c->own_pos == size - 1)
1458 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1459 GMP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
1461 add_to_peer (c, orig_peer);
1462 if (MESH_TUNNEL3_NEW == GMT_get_cstate (c->t))
1463 GMT_change_cstate (c->t, MESH_TUNNEL3_WAITING);
1465 send_connection_ack (c, GNUNET_NO);
1466 if (MESH_CONNECTION_SENT == c->state)
1467 connection_change_state (c, MESH_CONNECTION_ACK);
1469 /* Keep tunnel alive in direction dest->owner*/
1470 if (GNUNET_SCHEDULER_NO_TASK == c->bck_maintenance_task)
1472 c->bck_maintenance_task =
1473 GNUNET_SCHEDULER_add_delayed (create_connection_time,
1474 &connection_bck_keepalive, c);
1479 /* It's for somebody else! Retransmit. */
1480 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
1481 GMP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1482 GMP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
1483 GMC_send_prebuilt_message (message, c, GNUNET_YES, GNUNET_YES,
1486 path_destroy (path);
1492 * Core handler for path confirmations.
1494 * @param cls closure
1495 * @param message message
1496 * @param peer peer identity this notification is about
1498 * @return GNUNET_OK to keep the connection open,
1499 * GNUNET_SYSERR to close it (signal serious error)
1502 GMC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
1503 const struct GNUNET_MessageHeader *message)
1505 struct GNUNET_MESH_ConnectionACK *msg;
1506 struct MeshConnection *c;
1507 struct MeshPeerPath *p;
1508 struct MeshPeer *pi;
1509 enum MeshConnectionState oldstate;
1512 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1513 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received a connection ACK msg\n");
1514 msg = (struct GNUNET_MESH_ConnectionACK *) message;
1515 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n",
1516 GNUNET_h2s (&msg->cid));
1517 c = connection_get (&msg->cid);
1520 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1522 LOG (GNUNET_ERROR_TYPE_DEBUG, " don't know the connection!\n");
1526 if (GNUNET_NO != c->destroy)
1528 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection being destroyed\n");
1532 oldstate = c->state;
1533 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
1534 pi = GMP_get (peer);
1535 if (get_next_hop (c) == pi)
1537 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
1539 if (MESH_CONNECTION_SENT == oldstate)
1540 connection_change_state (c, MESH_CONNECTION_ACK);
1542 else if (get_prev_hop (c) == pi)
1544 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK\n");
1546 connection_change_state (c, MESH_CONNECTION_READY);
1550 GNUNET_break_op (0);
1554 connection_reset_timeout (c, fwd);
1556 /* Add path to peers? */
1560 GMP_add_path_to_all (p, GNUNET_YES);
1567 /* Message for us as creator? */
1568 if (GMC_is_origin (c, GNUNET_YES))
1570 if (GNUNET_NO != fwd)
1572 GNUNET_break_op (0);
1575 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
1577 /* If just created, cancel the short timeout and start a long one */
1578 if (MESH_CONNECTION_SENT == oldstate)
1579 connection_reset_timeout (c, GNUNET_YES);
1581 /* Change connection state */
1582 connection_change_state (c, MESH_CONNECTION_READY);
1583 send_connection_ack (c, GNUNET_YES);
1585 /* Change tunnel state, trigger KX */
1586 if (MESH_TUNNEL3_WAITING == GMT_get_cstate (c->t))
1587 GMT_change_cstate (c->t, MESH_TUNNEL3_READY);
1592 /* Message for us as destination? */
1593 if (GMC_is_terminal (c, GNUNET_YES))
1595 if (GNUNET_YES != fwd)
1597 GNUNET_break_op (0);
1600 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
1602 /* If just created, cancel the short timeout and start a long one */
1603 if (MESH_CONNECTION_ACK == oldstate)
1604 connection_reset_timeout (c, GNUNET_NO);
1606 /* Change tunnel state */
1607 if (MESH_TUNNEL3_WAITING == GMT_get_cstate (c->t))
1608 GMT_change_cstate (c->t, MESH_TUNNEL3_READY);
1613 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1614 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
1620 * Core handler for notifications of broken paths
1622 * @param cls Closure (unused).
1623 * @param id Peer identity of sending neighbor.
1624 * @param message Message.
1626 * @return GNUNET_OK to keep the connection open,
1627 * GNUNET_SYSERR to close it (signal serious error)
1630 GMC_handle_broken (void* cls,
1631 const struct GNUNET_PeerIdentity* id,
1632 const struct GNUNET_MessageHeader* message)
1634 struct GNUNET_MESH_ConnectionBroken *msg;
1635 struct MeshConnection *c;
1638 LOG (GNUNET_ERROR_TYPE_DEBUG,
1639 "Received a CONNECTION BROKEN msg from %s\n", GNUNET_i2s (id));
1640 msg = (struct GNUNET_MESH_ConnectionBroken *) message;
1641 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1642 GNUNET_i2s (&msg->peer1));
1643 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1644 GNUNET_i2s (&msg->peer2));
1645 c = connection_get (&msg->cid);
1648 GNUNET_break_op (0);
1652 fwd = is_fwd (c, id);
1653 if (GMC_is_terminal (c, fwd))
1655 if (0 < c->pending_messages)
1656 c->destroy = GNUNET_YES;
1662 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
1663 c->destroy = GNUNET_YES;
1664 connection_cancel_queues (c, !fwd);
1673 * Core handler for tunnel destruction
1675 * @param cls Closure (unused).
1676 * @param peer Peer identity of sending neighbor.
1677 * @param message Message.
1679 * @return GNUNET_OK to keep the connection open,
1680 * GNUNET_SYSERR to close it (signal serious error)
1683 GMC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
1684 const struct GNUNET_MessageHeader *message)
1686 struct GNUNET_MESH_ConnectionDestroy *msg;
1687 struct MeshConnection *c;
1690 msg = (struct GNUNET_MESH_ConnectionDestroy *) message;
1691 LOG (GNUNET_ERROR_TYPE_DEBUG,
1692 "Got a CONNECTION DESTROY message from %s\n",
1694 LOG (GNUNET_ERROR_TYPE_DEBUG,
1695 " for connection %s\n",
1696 GNUNET_h2s (&msg->cid));
1697 c = connection_get (&msg->cid);
1700 /* Probably already got the message from another path,
1701 * destroyed the tunnel and retransmitted to children.
1704 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1706 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection unknown: already destroyed?\n");
1709 fwd = is_fwd (c, peer);
1710 if (GNUNET_SYSERR == fwd)
1712 GNUNET_break_op (0); /* FIXME */
1715 if (GNUNET_NO == GMC_is_terminal (c, fwd))
1716 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
1717 else if (0 == c->pending_messages)
1719 LOG (GNUNET_ERROR_TYPE_DEBUG, "! directly destroying connection!\n");
1723 c->destroy = GNUNET_YES;
1724 c->state = MESH_CONNECTION_DESTROYED;
1727 GMT_remove_connection (c->t, c);
1735 * Generic handler for mesh network encrypted traffic.
1737 * @param peer Peer identity this notification is about.
1738 * @param msg Encrypted message.
1740 * @return GNUNET_OK to keep the connection open,
1741 * GNUNET_SYSERR to close it (signal serious error)
1744 handle_mesh_encrypted (const struct GNUNET_PeerIdentity *peer,
1745 const struct GNUNET_MESH_Encrypted *msg)
1747 struct MeshConnection *c;
1748 struct MeshPeer *neighbor;
1749 struct MeshFlowControl *fc;
1750 GNUNET_PEER_Id peer_id;
1758 size = ntohs (msg->header.size);
1760 sizeof (struct GNUNET_MESH_Encrypted) +
1761 sizeof (struct GNUNET_MessageHeader))
1763 GNUNET_break_op (0);
1766 type = ntohs (msg->header.type);
1767 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1768 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message (#%u) from %s\n",
1769 GM_m2s (type), ntohl (msg->pid), GNUNET_i2s (peer));
1771 /* Check connection */
1772 c = connection_get (&msg->cid);
1775 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1776 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING enc on unknown connection %s\n",
1777 GNUNET_h2s (&msg->cid));
1781 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n", GMC_2s (c));
1783 /* Check if origin is as expected */
1784 neighbor = get_prev_hop (c);
1785 peer_id = GNUNET_PEER_search (peer);
1786 if (peer_id == GMP_get_short_id (neighbor))
1792 neighbor = get_next_hop (c);
1793 if (peer_id == GMP_get_short_id (neighbor))
1799 /* Unexpected peer sending traffic on a connection. */
1800 GNUNET_break_op (0);
1806 fc = fwd ? &c->bck_fc : &c->fwd_fc;
1807 pid = ntohl (msg->pid);
1808 if (GM_is_pid_bigger (pid, fc->last_ack_sent))
1810 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
1811 LOG (GNUNET_ERROR_TYPE_DEBUG,
1812 "WARNING Received PID %u, (prev %u), ACK %u\n",
1813 pid, fc->last_pid_recv, fc->last_ack_sent);
1816 if (GNUNET_NO == GM_is_pid_bigger (pid, fc->last_pid_recv))
1818 GNUNET_STATISTICS_update (stats, "# duplicate PID", 1, GNUNET_NO);
1819 LOG (GNUNET_ERROR_TYPE_DEBUG,
1820 " Pid %u not expected (%u+), dropping!\n",
1821 pid, fc->last_pid_recv + 1);
1824 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1825 connection_change_state (c, MESH_CONNECTION_READY);
1826 connection_reset_timeout (c, fwd);
1827 fc->last_pid_recv = pid;
1829 /* Is this message for us? */
1830 if (GMC_is_terminal (c, fwd))
1832 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1833 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1837 GNUNET_break (GNUNET_NO != c->destroy);
1840 fc->last_pid_recv = pid;
1841 GMT_handle_encrypted (c->t, msg);
1842 GMC_send_ack (c, fwd, GNUNET_NO);
1846 /* Message not for us: forward to next hop */
1847 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1848 ttl = ntohl (msg->ttl);
1849 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
1852 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
1853 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
1854 GMC_send_ack (c, fwd, GNUNET_NO);
1858 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1859 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_NO, NULL, NULL);
1865 * Generic handler for mesh network encrypted traffic.
1867 * @param peer Peer identity this notification is about.
1868 * @param msg Encrypted message.
1870 * @return GNUNET_OK to keep the connection open,
1871 * GNUNET_SYSERR to close it (signal serious error)
1874 handle_mesh_kx (const struct GNUNET_PeerIdentity *peer,
1875 const struct GNUNET_MESH_KX *msg)
1877 struct MeshConnection *c;
1878 struct MeshPeer *neighbor;
1879 GNUNET_PEER_Id peer_id;
1885 size = ntohs (msg->header.size);
1887 sizeof (struct GNUNET_MESH_Encrypted) +
1888 sizeof (struct GNUNET_MessageHeader))
1890 GNUNET_break_op (0);
1893 type = ntohs (msg->header.type);
1894 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
1895 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a %s message from %s\n",
1896 GM_m2s (type), GNUNET_i2s (peer));
1898 /* Check connection */
1899 c = connection_get (&msg->cid);
1902 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1903 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING kx on unknown connection %s\n",
1904 GNUNET_h2s (&msg->cid));
1907 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n", GMC_2s (c));
1909 /* Check if origin is as expected */
1910 neighbor = get_prev_hop (c);
1911 peer_id = GNUNET_PEER_search (peer);
1912 if (peer_id == GMP_get_short_id (neighbor))
1918 neighbor = get_next_hop (c);
1919 if (peer_id == GMP_get_short_id (neighbor))
1925 /* Unexpected peer sending traffic on a connection. */
1926 GNUNET_break_op (0);
1931 /* Count as connection confirmation. */
1932 if (MESH_CONNECTION_SENT == c->state || MESH_CONNECTION_ACK == c->state)
1934 connection_change_state (c, MESH_CONNECTION_READY);
1937 if (MESH_TUNNEL3_WAITING == GMT_get_cstate (c->t))
1938 GMT_change_cstate (c->t, MESH_TUNNEL3_READY);
1941 connection_reset_timeout (c, fwd);
1943 /* Is this message for us? */
1944 if (GMC_is_terminal (c, fwd))
1946 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
1947 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
1953 GMT_handle_kx (c->t, &msg[1].header);
1957 /* Message not for us: forward to next hop */
1958 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1959 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
1960 GMC_send_prebuilt_message (&msg->header, c, fwd, GNUNET_NO, NULL, NULL);
1967 * Core handler for encrypted mesh network traffic (channel mgmt, data).
1969 * @param cls Closure (unused).
1970 * @param message Message received.
1971 * @param peer Peer who sent the message.
1973 * @return GNUNET_OK to keep the connection open,
1974 * GNUNET_SYSERR to close it (signal serious error)
1977 GMC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
1978 const struct GNUNET_MessageHeader *message)
1980 return handle_mesh_encrypted (peer,
1981 (struct GNUNET_MESH_Encrypted *)message);
1986 * Core handler for key exchange traffic (ephemeral key, ping, pong).
1988 * @param cls Closure (unused).
1989 * @param message Message received.
1990 * @param peer Peer who sent the message.
1992 * @return GNUNET_OK to keep the connection open,
1993 * GNUNET_SYSERR to close it (signal serious error)
1996 GMC_handle_kx (void *cls, const struct GNUNET_PeerIdentity *peer,
1997 const struct GNUNET_MessageHeader *message)
1999 return handle_mesh_kx (peer,
2000 (struct GNUNET_MESH_KX *) message);
2005 * Core handler for mesh network traffic point-to-point acks.
2007 * @param cls closure
2008 * @param message message
2009 * @param peer peer identity this notification is about
2011 * @return GNUNET_OK to keep the connection open,
2012 * GNUNET_SYSERR to close it (signal serious error)
2015 GMC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
2016 const struct GNUNET_MessageHeader *message)
2018 struct GNUNET_MESH_ACK *msg;
2019 struct MeshConnection *c;
2020 struct MeshFlowControl *fc;
2025 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
2026 LOG (GNUNET_ERROR_TYPE_DEBUG, "Got an ACK packet from %s!\n",
2028 msg = (struct GNUNET_MESH_ACK *) message;
2030 c = connection_get (&msg->cid);
2034 GNUNET_STATISTICS_update (stats, "# ack on unknown connection", 1,
2039 /* Is this a forward or backward ACK? */
2040 id = GNUNET_PEER_search (peer);
2041 if (GMP_get_short_id (get_next_hop (c)) == id)
2043 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
2047 else if (GMP_get_short_id (get_prev_hop (c)) == id)
2049 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
2055 GNUNET_break_op (0);
2059 ack = ntohl (msg->ack);
2060 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u (was %u)\n",
2061 ack, fc->last_ack_recv);
2062 if (GM_is_pid_bigger (ack, fc->last_ack_recv))
2063 fc->last_ack_recv = ack;
2065 /* Cancel polling if the ACK is big enough. */
2066 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task &&
2067 GM_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2069 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2070 GNUNET_SCHEDULER_cancel (fc->poll_task);
2071 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2072 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2075 connection_unlock_queue (c, fwd);
2082 * Core handler for mesh network traffic point-to-point ack polls.
2084 * @param cls closure
2085 * @param message message
2086 * @param peer peer identity this notification is about
2088 * @return GNUNET_OK to keep the connection open,
2089 * GNUNET_SYSERR to close it (signal serious error)
2092 GMC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
2093 const struct GNUNET_MessageHeader *message)
2095 struct GNUNET_MESH_Poll *msg;
2096 struct MeshConnection *c;
2097 struct MeshFlowControl *fc;
2102 LOG (GNUNET_ERROR_TYPE_DEBUG, "\n\n");
2103 LOG (GNUNET_ERROR_TYPE_DEBUG,
2104 "Got a POLL message from %s!\n",
2107 msg = (struct GNUNET_MESH_Poll *) message;
2109 c = connection_get (&msg->cid);
2113 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2115 LOG (GNUNET_ERROR_TYPE_DEBUG,
2116 "WARNING POLL message on unknown connection %s!\n",
2117 GNUNET_h2s (&msg->cid));
2121 /* Is this a forward or backward ACK?
2122 * Note: a poll should never be needed in a loopback case,
2123 * since there is no possiblility of packet loss there, so
2124 * this way of discerining FWD/BCK should not be a problem.
2126 id = GNUNET_PEER_search (peer);
2127 if (GMP_get_short_id (get_next_hop (c)) == id)
2129 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2132 else if (GMP_get_short_id (get_prev_hop (c)) == id)
2134 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2139 GNUNET_break_op (0);
2143 pid = ntohl (msg->pid);
2144 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2145 fc->last_pid_recv = pid;
2146 fwd = fc == &c->bck_fc;
2147 GMC_send_ack (c, fwd, GNUNET_YES);
2154 * Core handler for mesh keepalives.
2156 * @param cls closure
2157 * @param message message
2158 * @param peer peer identity this notification is about
2159 * @return GNUNET_OK to keep the connection open,
2160 * GNUNET_SYSERR to close it (signal serious error)
2162 * TODO: Check who we got this from, to validate route.
2165 GMC_handle_keepalive (void *cls, const struct GNUNET_PeerIdentity *peer,
2166 const struct GNUNET_MessageHeader *message)
2168 struct GNUNET_MESH_ConnectionKeepAlive *msg;
2169 struct MeshConnection *c;
2170 struct MeshPeer *neighbor;
2171 GNUNET_PEER_Id peer_id;
2174 msg = (struct GNUNET_MESH_ConnectionKeepAlive *) message;
2175 LOG (GNUNET_ERROR_TYPE_DEBUG, "got a keepalive packet from %s\n",
2178 c = connection_get (&msg->cid);
2181 GNUNET_STATISTICS_update (stats, "# keepalive on unknown connection", 1,
2186 /* Check if origin is as expected TODO refactor and reuse */
2187 peer_id = GNUNET_PEER_search (peer);
2188 neighbor = get_prev_hop (c);
2189 if (peer_id == GMP_get_short_id (neighbor))
2195 neighbor = get_next_hop (c);
2196 if (peer_id == GMP_get_short_id (neighbor))
2202 GNUNET_break_op (0);
2207 connection_change_state (c, MESH_CONNECTION_READY);
2208 connection_reset_timeout (c, fwd);
2210 if (GMC_is_terminal (c, fwd))
2213 GNUNET_STATISTICS_update (stats, "# keepalives forwarded", 1, GNUNET_NO);
2214 GMC_send_prebuilt_message (message, c, fwd, GNUNET_YES, NULL, NULL);
2221 * Send an ACK on the appropriate connection/channel, depending on
2222 * the direction and the position of the peer.
2224 * @param c Which connection to send the hop-by-hop ACK.
2225 * @param fwd Is this a fwd ACK? (will go dest->root).
2226 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2229 GMC_send_ack (struct MeshConnection *c, int fwd, int force)
2231 unsigned int buffer;
2233 LOG (GNUNET_ERROR_TYPE_DEBUG,
2234 "GMC send %s ACK on %s\n",
2235 GM_f2s (fwd), GMC_2s (c));
2243 if (GNUNET_NO != c->destroy)
2245 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2249 /* Get available buffer space */
2250 if (GMC_is_terminal (c, fwd))
2252 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2253 buffer = GMT_get_channels_buffer (c->t);
2257 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2258 buffer = GMC_get_buffer (c, fwd);
2260 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2261 if (0 == buffer && GNUNET_NO == force)
2264 /* Send available buffer space */
2265 if (GMC_is_origin (c, fwd))
2267 GNUNET_assert (NULL != c->t);
2268 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2269 GMT_unchoke_channels (c->t);
2273 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2274 send_ack (c, buffer, fwd, force);
2280 * Initialize the connections subsystem
2282 * @param c Configuration handle.
2285 GMC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2287 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2289 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_MSGS_QUEUE",
2292 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2293 "MESH", "MAX_MSGS_QUEUE", "MISSING");
2294 GNUNET_SCHEDULER_shutdown ();
2299 GNUNET_CONFIGURATION_get_value_number (c, "MESH", "MAX_CONNECTIONS",
2302 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2303 "MESH", "MAX_CONNECTIONS", "MISSING");
2304 GNUNET_SCHEDULER_shutdown ();
2309 GNUNET_CONFIGURATION_get_value_time (c, "MESH", "REFRESH_CONNECTION_TIME",
2310 &refresh_connection_time))
2312 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2313 "MESH", "REFRESH_CONNECTION_TIME", "MISSING");
2314 GNUNET_SCHEDULER_shutdown ();
2317 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2318 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_YES);
2323 * Destroy each connection on shutdown.
2325 * @param cls Closure (unused).
2326 * @param key Current key code (CID, unused).
2327 * @param value Value in the hash map (connection)
2329 * @return #GNUNET_YES, because we should continue to iterate,
2332 shutdown_iterator (void *cls,
2333 const struct GNUNET_HashCode *key,
2336 struct MeshConnection *c = value;
2344 * Shut down the connections subsystem.
2349 GNUNET_CONTAINER_multihashmap_iterate (connections, &shutdown_iterator, NULL);
2350 GNUNET_CONTAINER_multihashmap_destroy (connections);
2355 struct MeshConnection *
2356 GMC_new (const struct GNUNET_HashCode *cid,
2357 struct MeshTunnel3 *t,
2358 struct MeshPeerPath *p,
2359 unsigned int own_pos)
2361 struct MeshConnection *c;
2363 c = GNUNET_new (struct MeshConnection);
2365 GNUNET_assert (GNUNET_OK ==
2366 GNUNET_CONTAINER_multihashmap_put (connections,
2368 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2369 fc_init (&c->fwd_fc);
2370 fc_init (&c->bck_fc);
2375 GNUNET_assert (own_pos <= p->length - 1);
2376 c->own_pos = own_pos;
2379 if (GNUNET_OK != register_neighbors (c))
2383 path_invalidate (c->path);
2393 c->fwd_maintenance_task =
2394 GNUNET_SCHEDULER_add_delayed (create_connection_time,
2395 &connection_fwd_keepalive, c);
2403 GMC_destroy (struct MeshConnection *c)
2411 if (2 == c->destroy) /* cancel queues -> GMP_queue_cancel -> q_destroy -> */
2412 return; /* -> message_sent -> GMC_destroy. Don't loop. */
2415 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying connection %s\n", GMC_2s (c));
2416 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc's f: %p, b: %p\n",
2417 &c->fwd_fc, &c->bck_fc);
2418 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2419 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2421 /* Cancel all traffic */
2422 if (NULL != c->path)
2424 connection_cancel_queues (c, GNUNET_YES);
2425 connection_cancel_queues (c, GNUNET_NO);
2426 unregister_neighbors (c);
2429 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2430 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2432 /* Cancel maintainance task (keepalive/timeout) */
2433 if (NULL != c->fwd_fc.poll_msg)
2435 GMC_cancel (c->fwd_fc.poll_msg);
2436 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg FWD canceled\n");
2438 if (NULL != c->bck_fc.poll_msg)
2440 GMC_cancel (c->bck_fc.poll_msg);
2441 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg BCK canceled\n");
2444 /* Delete from tunnel */
2446 GMT_remove_connection (c->t, c);
2448 if (GNUNET_NO == GMC_is_origin (c, GNUNET_YES) && NULL != c->path)
2449 path_destroy (c->path);
2450 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_maintenance_task)
2451 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2452 if (GNUNET_SCHEDULER_NO_TASK != c->bck_maintenance_task)
2453 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2454 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_fc.poll_task)
2456 GNUNET_SCHEDULER_cancel (c->fwd_fc.poll_task);
2457 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL FWD canceled\n");
2459 if (GNUNET_SCHEDULER_NO_TASK != c->bck_fc.poll_task)
2461 GNUNET_SCHEDULER_cancel (c->bck_fc.poll_task);
2462 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL BCK canceled\n");
2465 GNUNET_break (GNUNET_YES ==
2466 GNUNET_CONTAINER_multihashmap_remove (connections, &c->id, c));
2468 GNUNET_STATISTICS_update (stats, "# connections", -1, GNUNET_NO);
2473 * Get the connection ID.
2475 * @param c Connection to get the ID from.
2477 * @return ID of the connection.
2479 const struct GNUNET_HashCode *
2480 GMC_get_id (const struct MeshConnection *c)
2487 * Get the connection path.
2489 * @param c Connection to get the path from.
2491 * @return path used by the connection.
2493 const struct MeshPeerPath *
2494 GMC_get_path (const struct MeshConnection *c)
2496 if (GNUNET_NO == c->destroy)
2503 * Get the connection state.
2505 * @param c Connection to get the state from.
2507 * @return state of the connection.
2509 enum MeshConnectionState
2510 GMC_get_state (const struct MeshConnection *c)
2516 * Get the connection tunnel.
2518 * @param c Connection to get the tunnel from.
2520 * @return tunnel of the connection.
2522 struct MeshTunnel3 *
2523 GMC_get_tunnel (const struct MeshConnection *c)
2530 * Get free buffer space in a connection.
2532 * @param c Connection.
2533 * @param fwd Is query about FWD traffic?
2535 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2538 GMC_get_buffer (struct MeshConnection *c, int fwd)
2540 struct MeshFlowControl *fc;
2542 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2544 return (fc->queue_max - fc->queue_n);
2548 * Get how many messages have we allowed to send to us from a direction.
2550 * @param c Connection.
2551 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2553 * @return last_ack_sent - last_pid_recv
2556 GMC_get_allowed (struct MeshConnection *c, int fwd)
2558 struct MeshFlowControl *fc;
2560 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2561 if (GM_is_pid_bigger(fc->last_pid_recv, fc->last_ack_sent))
2565 return (fc->last_ack_sent - fc->last_pid_recv);
2569 * Get messages queued in a connection.
2571 * @param c Connection.
2572 * @param fwd Is query about FWD traffic?
2574 * @return Number of messages queued.
2577 GMC_get_qn (struct MeshConnection *c, int fwd)
2579 struct MeshFlowControl *fc;
2581 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2588 * Allow the connection to advertise a buffer of the given size.
2590 * The connection will send an @c fwd ACK message (so: in direction !fwd)
2591 * allowing up to last_pid_recv + buffer.
2593 * @param c Connection.
2594 * @param buffer How many more messages the connection can accept.
2595 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
2598 GMC_allow (struct MeshConnection *c, unsigned int buffer, int fwd)
2600 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
2601 GMC_2s (c), buffer, GM_f2s (fwd));
2602 send_ack (c, buffer, fwd, GNUNET_NO);
2607 * Notify other peers on a connection of a broken link. Mark connections
2608 * to destroy after all traffic has been sent.
2610 * @param c Connection on which there has been a disconnection.
2611 * @param peer Peer that disconnected.
2614 GMC_notify_broken (struct MeshConnection *c,
2615 struct MeshPeer *peer)
2619 LOG (GNUNET_ERROR_TYPE_DEBUG,
2620 " notify broken on %s due to %s disconnect\n",
2621 GMC_2s (c), GMP_2s (peer));
2623 fwd = peer == get_prev_hop (c);
2625 if (GNUNET_YES == GMC_is_terminal (c, fwd))
2627 /* Local shutdown, no one to notify about this. */
2631 if (GNUNET_NO == c->destroy)
2632 send_broken (c, &my_full_id, GMP_get_id (peer), fwd);
2634 /* Connection will have at least one pending message
2635 * (the one we just scheduled), so no point in checking whether to
2636 * destroy immediately. */
2637 c->destroy = GNUNET_YES;
2638 c->state = MESH_CONNECTION_DESTROYED;
2641 * Cancel all queues, if no message is left, connection will be destroyed.
2643 connection_cancel_queues (c, !fwd);
2650 * Is this peer the first one on the connection?
2652 * @param c Connection.
2653 * @param fwd Is this about fwd traffic?
2655 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
2658 GMC_is_origin (struct MeshConnection *c, int fwd)
2660 if (!fwd && c->path->length - 1 == c->own_pos )
2662 if (fwd && 0 == c->own_pos)
2669 * Is this peer the last one on the connection?
2671 * @param c Connection.
2672 * @param fwd Is this about fwd traffic?
2673 * Note that the ROOT is the terminal for BCK traffic!
2675 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
2678 GMC_is_terminal (struct MeshConnection *c, int fwd)
2680 return GMC_is_origin (c, !fwd);
2685 * See if we are allowed to send by the next hop in the given direction.
2687 * @param c Connection.
2688 * @param fwd Is this about fwd traffic?
2690 * @return #GNUNET_YES in case it's OK to send.
2693 GMC_is_sendable (struct MeshConnection *c, int fwd)
2695 struct MeshFlowControl *fc;
2697 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2698 if (GM_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2704 * Sends an already built message on a connection, properly registering
2705 * all used resources.
2707 * @param message Message to send. Function makes a copy of it.
2708 * If message is not hop-by-hop, decrements TTL of copy.
2709 * @param c Connection on which this message is transmitted.
2710 * @param fwd Is this a fwd message?
2711 * @param force Force the connection to accept the message (buffer overfill).
2712 * @param cont Continuation called once message is sent. Can be NULL.
2713 * @param cont_cls Closure for @c cont.
2715 * @return Handle to cancel the message before it's sent.
2716 * NULL on error or if @c cont is NULL.
2717 * Invalid on @c cont call.
2719 struct MeshConnectionQueue *
2720 GMC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2721 struct MeshConnection *c, int fwd, int force,
2722 GMC_sent cont, void *cont_cls)
2724 struct MeshFlowControl *fc;
2725 struct MeshConnectionQueue *q;
2731 size = ntohs (message->size);
2732 data = GNUNET_malloc (size);
2733 memcpy (data, message, size);
2734 type = ntohs (message->type);
2735 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send %s (%u bytes) on connection %s\n",
2736 GM_m2s (type), size, GMC_2s (c));
2738 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2739 droppable = GNUNET_NO == force;
2742 struct GNUNET_MESH_Encrypted *emsg;
2743 struct GNUNET_MESH_KX *kmsg;
2744 struct GNUNET_MESH_ACK *amsg;
2745 struct GNUNET_MESH_Poll *pmsg;
2746 struct GNUNET_MESH_ConnectionDestroy *dmsg;
2747 struct GNUNET_MESH_ConnectionBroken *bmsg;
2750 case GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED:
2751 emsg = (struct GNUNET_MESH_Encrypted *) data;
2752 ttl = ntohl (emsg->ttl);
2755 GNUNET_break_op (0);
2760 emsg->ttl = htonl (ttl - 1);
2761 emsg->pid = htonl (fc->next_pid++);
2762 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
2763 if (GNUNET_YES == droppable)
2766 LOG (GNUNET_ERROR_TYPE_DEBUG, "pid %u\n", ntohl (emsg->pid));
2767 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
2768 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
2772 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
2774 if (GM_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
2776 GMC_start_poll (c, fwd);
2780 case GNUNET_MESSAGE_TYPE_MESH_KX:
2781 kmsg = (struct GNUNET_MESH_KX *) data;
2785 case GNUNET_MESSAGE_TYPE_MESH_ACK:
2786 amsg = (struct GNUNET_MESH_ACK *) data;
2788 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
2789 droppable = GNUNET_NO;
2792 case GNUNET_MESSAGE_TYPE_MESH_POLL:
2793 pmsg = (struct GNUNET_MESH_Poll *) data;
2795 LOG (GNUNET_ERROR_TYPE_DEBUG, " poll %u\n", ntohl (pmsg->pid));
2796 droppable = GNUNET_NO;
2799 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY:
2800 dmsg = (struct GNUNET_MESH_ConnectionDestroy *) data;
2805 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_BROKEN:
2806 bmsg = (struct GNUNET_MESH_ConnectionBroken *) data;
2811 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE:
2812 case GNUNET_MESSAGE_TYPE_MESH_CONNECTION_ACK:
2813 case GNUNET_MESSAGE_TYPE_MESH_KEEPALIVE:
2822 if (fc->queue_n > fc->queue_max && droppable)
2824 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
2827 LOG (GNUNET_ERROR_TYPE_DEBUG,
2828 "queue full: %u/%u\n",
2829 fc->queue_n, fc->queue_max);
2830 if (GNUNET_MESSAGE_TYPE_MESH_ENCRYPTED == type)
2836 return NULL; /* Drop this message */
2839 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u\n", c, c->pending_messages);
2840 c->pending_messages++;
2842 q = GNUNET_new (struct MeshConnectionQueue);
2843 q->forced = !droppable;
2844 q->q = GMP_queue_add (get_hop (c, fwd), data, type, size, c, fwd,
2848 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING dropping msg on %s\n", GMC_2s (c));
2854 q->cont_cls = cont_cls;
2860 * Cancel a previously sent message while it's in the queue.
2862 * ONLY can be called before the continuation given to the send function
2863 * is called. Once the continuation is called, the message is no longer in the
2866 * @param q Handle to the queue.
2869 GMC_cancel (struct MeshConnectionQueue *q)
2871 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GMC cancel message\n");
2873 /* queue destroy calls message_sent, which calls q->cont and frees q */
2874 GMP_queue_destroy (q->q, GNUNET_YES);
2879 * Sends a CREATE CONNECTION message for a path to a peer.
2880 * Changes the connection and tunnel states if necessary.
2882 * @param connection Connection to create.
2885 GMC_send_create (struct MeshConnection *connection)
2887 enum MeshTunnel3CState state;
2890 size = sizeof (struct GNUNET_MESH_ConnectionCreate);
2891 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
2893 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send connection create\n");
2894 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
2895 connection, connection->pending_messages);
2896 connection->pending_messages++;
2898 GMP_queue_add (get_next_hop (connection), NULL,
2899 GNUNET_MESSAGE_TYPE_MESH_CONNECTION_CREATE,
2900 size, connection, GNUNET_YES, &message_sent, NULL);
2902 state = GMT_get_cstate (connection->t);
2903 if (MESH_TUNNEL3_SEARCHING == state || MESH_TUNNEL3_NEW == state)
2904 GMT_change_cstate (connection->t, MESH_TUNNEL3_WAITING);
2905 if (MESH_CONNECTION_NEW == connection->state)
2906 connection_change_state (connection, MESH_CONNECTION_SENT);
2911 * Send a message to all peers in this connection that the connection
2912 * is no longer valid.
2914 * If some peer should not receive the message, it should be zero'ed out
2915 * before calling this function.
2917 * @param c The connection whose peers to notify.
2920 GMC_send_destroy (struct MeshConnection *c)
2922 struct GNUNET_MESH_ConnectionDestroy msg;
2924 if (GNUNET_YES == c->destroy)
2927 msg.header.size = htons (sizeof (msg));
2928 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CONNECTION_DESTROY);;
2930 LOG (GNUNET_ERROR_TYPE_DEBUG,
2931 " sending connection destroy for connection %s\n",
2934 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_YES))
2935 GMC_send_prebuilt_message (&msg.header, c,
2936 GNUNET_YES, GNUNET_YES, NULL, NULL);
2937 if (GNUNET_NO == GMC_is_terminal (c, GNUNET_NO))
2938 GMC_send_prebuilt_message (&msg.header, c,
2939 GNUNET_NO, GNUNET_YES, NULL, NULL);
2940 c->destroy = GNUNET_YES;
2941 c->state = MESH_CONNECTION_DESTROYED;
2946 * @brief Start a polling timer for the connection.
2948 * When a neighbor does not accept more traffic on the connection it could be
2949 * caused by a simple congestion or by a lost ACK. Polling enables to check
2950 * for the lastest ACK status for a connection.
2952 * @param c Connection.
2953 * @param fwd Should we poll in the FWD direction?
2956 GMC_start_poll (struct MeshConnection *c, int fwd)
2958 struct MeshFlowControl *fc;
2960 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2961 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL %s requested\n",
2963 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task || NULL != fc->poll_msg)
2965 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** not needed (%u, %p)\n",
2966 fc->poll_task, fc->poll_msg);
2969 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL started on request\n");
2970 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
2977 * @brief Stop polling a connection for ACKs.
2979 * Once we have enough ACKs for future traffic, polls are no longer necessary.
2981 * @param c Connection.
2982 * @param fwd Should we stop the poll in the FWD direction?
2985 GMC_stop_poll (struct MeshConnection *c, int fwd)
2987 struct MeshFlowControl *fc;
2989 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2990 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
2992 GNUNET_SCHEDULER_cancel (fc->poll_task);
2993 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2998 * Get a (static) string for a connection.
3000 * @param c Connection.
3003 GMC_2s (const struct MeshConnection *c)
3010 static char buf[128];
3012 sprintf (buf, "%s (->%s)", GNUNET_h2s (&c->id), GMT_2s (c->t));
3015 return GNUNET_h2s (&c->id);