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.
10 GNUnet is distributed in the hope that it will be useful, but
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 cadet/gnunet-service-cadet_connection.c
23 * @brief GNUnet CADET service connection handling
24 * @author Bartlomiej Polot
28 #include "gnunet_util_lib.h"
30 #include "gnunet_statistics_service.h"
32 #include "cadet_path.h"
33 #include "cadet_protocol.h"
35 #include "gnunet-service-cadet_connection.h"
36 #include "gnunet-service-cadet_peer.h"
37 #include "gnunet-service-cadet_tunnel.h"
40 #define LOG(level, ...) GNUNET_log_from (level,"cadet-con",__VA_ARGS__)
42 #define CADET_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 CadetFlowControl
59 * Connection this controls.
61 struct CadetConnection *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;
74 * ID of the last packet sent towards the peer.
76 uint32_t last_pid_sent;
79 * ID of the last packet received from the peer.
81 uint32_t last_pid_recv;
84 * Last ACK sent to the peer (peer can't send more than this PID).
86 uint32_t last_ack_sent;
89 * Last ACK sent towards the origin (for traffic towards leaf node).
91 uint32_t last_ack_recv;
94 * Task to poll the peer in case of a lost ACK causes stall.
96 GNUNET_SCHEDULER_TaskIdentifier poll_task;
99 * How frequently to poll for ACKs.
101 struct GNUNET_TIME_Relative poll_time;
104 * Queued poll message, to cancel if not necessary anymore (got ACK).
106 struct CadetConnectionQueue *poll_msg;
109 * Queued poll message, to cancel if not necessary anymore (got ACK).
111 struct CadetConnectionQueue *ack_msg;
115 * Keep a record of the last messages sent on this connection.
117 struct CadetConnectionPerformance
120 * Circular buffer for storing measurements.
122 double usecsperbyte[AVG_MSGS];
125 * Running average of @c usecsperbyte.
130 * How many values of @c usecsperbyte are valid.
135 * Index of the next "free" position in @c usecsperbyte.
142 * Struct containing all information regarding a connection to a peer.
144 struct CadetConnection
147 * Tunnel this connection is part of.
149 struct CadetTunnel *t;
152 * Flow control information for traffic fwd.
154 struct CadetFlowControl fwd_fc;
157 * Flow control information for traffic bck.
159 struct CadetFlowControl bck_fc;
162 * Measure connection performance on the endpoint.
164 struct CadetConnectionPerformance *perf;
167 * ID of the connection.
169 struct GNUNET_CADET_Hash id;
172 * State of the connection.
174 enum CadetConnectionState state;
177 * Path being used for the tunnel. At the origin of the connection
178 * it's a pointer to the destination's path pool, otherwise just a copy.
180 struct CadetPeerPath *path;
183 * Position of the local peer in the path.
185 unsigned int own_pos;
188 * Task to keep the used paths alive at the owner,
189 * time tunnel out on all the other peers.
191 GNUNET_SCHEDULER_TaskIdentifier fwd_maintenance_task;
194 * Task to keep the used paths alive at the destination,
195 * time tunnel out on all the other peers.
197 GNUNET_SCHEDULER_TaskIdentifier bck_maintenance_task;
200 * Queue handle for maintainance traffic. One handle for FWD and BCK since
201 * one peer never needs to maintain both directions (no loopback connections).
203 struct CadetPeerQueue *maintenance_q;
206 * Counter to do exponential backoff when creating a connection (max 64).
208 unsigned short create_retry;
211 * Pending message count.
213 int pending_messages;
216 * Destroy flag: if true, destroy on last message.
222 * Handle for messages queued but not yet sent.
224 struct CadetConnectionQueue
227 * Peer queue handle, to cancel if necessary.
229 struct CadetPeerQueue *q;
232 * Was this a forced message? (Do not account for it)
237 * Continuation to call once sent.
242 * Closure for @c cont.
247 /******************************************************************************/
248 /******************************* GLOBALS ***********************************/
249 /******************************************************************************/
252 * Global handle to the statistics service.
254 extern struct GNUNET_STATISTICS_Handle *stats;
257 * Local peer own ID (memory efficient handle).
259 extern GNUNET_PEER_Id myid;
262 * Local peer own ID (full value).
264 extern struct GNUNET_PeerIdentity my_full_id;
267 * Connections known, indexed by cid (CadetConnection).
269 static struct GNUNET_CONTAINER_MultiHashMap *connections;
272 * How many connections are we willing to maintain.
273 * Local connections are always allowed, even if there are more connections than max.
275 static unsigned long long max_connections;
278 * How many messages *in total* are we willing to queue, divide by number of
279 * connections to get connection queue size.
281 static unsigned long long max_msgs_queue;
284 * How often to send path keepalives. Paths timeout after 4 missed.
286 static struct GNUNET_TIME_Relative refresh_connection_time;
289 * How often to send path create / ACKs.
291 static struct GNUNET_TIME_Relative create_connection_time;
294 /******************************************************************************/
295 /******************************** STATIC ***********************************/
296 /******************************************************************************/
298 #if 0 // avoid compiler warning for unused static function
300 fc_debug (struct CadetFlowControl *fc)
302 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
303 fc->last_pid_recv, fc->last_ack_sent);
304 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
305 fc->last_pid_sent, fc->last_ack_recv);
306 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
307 fc->queue_n, fc->queue_max);
311 connection_debug (struct CadetConnection *c)
315 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CONNECTION ***\n");
318 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
319 peer2s (c->t->peer), GCC_2s (c));
320 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
321 c->state, c->pending_messages);
322 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
323 fc_debug (&c->fwd_fc);
324 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
325 fc_debug (&c->bck_fc);
331 * Schedule next keepalive task, taking in consideration
332 * the connection state and number of retries.
334 * @param c Connection for which to schedule the next keepalive.
335 * @param fwd Direction for the next keepalive.
338 schedule_next_keepalive (struct CadetConnection *c, int fwd);
342 * Resets the connection timeout task, some other message has done the
344 * - For the first peer on the direction this means to send
345 * a keepalive or a path confirmation message (either create or ACK).
346 * - For all other peers, this means to destroy the connection,
347 * due to lack of activity.
348 * Starts the timeout if no timeout was running (connection just created).
350 * @param c Connection whose timeout to reset.
351 * @param fwd Is this forward?
354 connection_reset_timeout (struct CadetConnection *c, int fwd);
358 * Get string description for tunnel state. Reentrant.
360 * @param s Tunnel state.
362 * @return String representation.
365 GCC_state2s (enum CadetConnectionState s)
369 case CADET_CONNECTION_NEW:
370 return "CADET_CONNECTION_NEW";
371 case CADET_CONNECTION_SENT:
372 return "CADET_CONNECTION_SENT";
373 case CADET_CONNECTION_ACK:
374 return "CADET_CONNECTION_ACK";
375 case CADET_CONNECTION_READY:
376 return "CADET_CONNECTION_READY";
377 case CADET_CONNECTION_DESTROYED:
378 return "CADET_CONNECTION_DESTROYED";
380 return "CADET_CONNECTION_STATE_ERROR";
386 * Initialize a Flow Control structure to the initial state.
388 * @param fc Flow Control structure to initialize.
391 fc_init (struct CadetFlowControl *fc)
393 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
394 fc->last_pid_recv = (uint32_t) -1;
395 fc->last_ack_sent = (uint32_t) 0;
396 fc->last_ack_recv = (uint32_t) 0;
397 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
398 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
400 fc->queue_max = (max_msgs_queue / max_connections) + 1;
407 * @param cid Connection ID.
409 static struct CadetConnection *
410 connection_get (const struct GNUNET_CADET_Hash *cid)
412 return GNUNET_CONTAINER_multihashmap_get (connections, GC_h2hc (cid));
417 connection_change_state (struct CadetConnection* c,
418 enum CadetConnectionState state)
420 LOG (GNUNET_ERROR_TYPE_DEBUG,
421 "Connection %s state %s -> %s\n",
422 GCC_2s (c), GCC_state2s (c->state), GCC_state2s (state));
423 if (CADET_CONNECTION_DESTROYED == c->state)
425 LOG (GNUNET_ERROR_TYPE_DEBUG, "state not changing anymore\n");
429 if (CADET_CONNECTION_READY == state)
435 * Callback called when a queued ACK message is sent.
437 * @param cls Closure (FC).
438 * @param c Connection this message was on.
439 * @param q Queue handler this call invalidates.
440 * @param type Type of message sent.
441 * @param fwd Was this a FWD going message?
442 * @param size Size of the message.
446 struct CadetConnection *c,
447 struct CadetConnectionQueue *q,
448 uint16_t type, int fwd, size_t size)
450 struct CadetFlowControl *fc = cls;
457 * Send an ACK on the connection, informing the predecessor about
458 * the available buffer space. Should not be called in case the peer
459 * is origin (no predecessor) in the @c fwd direction.
461 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
462 * the ACK itself goes "back" (dest->root).
464 * @param c Connection on which to send the ACK.
465 * @param buffer How much space free to advertise?
466 * @param fwd Is this FWD ACK? (Going dest -> root)
467 * @param force Don't optimize out.
470 send_ack (struct CadetConnection *c, unsigned int buffer, int fwd, int force)
472 struct CadetFlowControl *next_fc;
473 struct CadetFlowControl *prev_fc;
474 struct GNUNET_CADET_ACK msg;
478 /* If origin, there is no connection to send ACKs. Wrong function! */
479 if (GCC_is_origin (c, fwd))
481 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection %s is origin in %s\n",
482 GCC_2s (c), GC_f2s (fwd));
487 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
488 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
490 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection send %s ack on %s\n",
491 GC_f2s (fwd), GCC_2s (c));
493 /* Check if we need to transmit the ACK. */
494 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
495 if (3 < delta && buffer < delta && GNUNET_NO == force)
497 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
498 LOG (GNUNET_ERROR_TYPE_DEBUG,
499 " last pid recv: %u, last ack sent: %u\n",
500 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
504 /* Ok, ACK might be necessary, what PID to ACK? */
505 ack = prev_fc->last_pid_recv + buffer;
506 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
507 LOG (GNUNET_ERROR_TYPE_DEBUG,
508 " last pid %u, last ack %u, qmax %u, q %u\n",
509 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
510 next_fc->queue_max, next_fc->queue_n);
511 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
513 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
517 /* Check if message is already in queue */
518 if (NULL != prev_fc->ack_msg)
520 if (GC_is_pid_bigger (ack, prev_fc->last_ack_sent))
522 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
523 GCC_cancel (prev_fc->ack_msg);
524 /* GCC_cancel triggers ack_sent(), which clears fc->ack_msg */
528 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
533 prev_fc->last_ack_sent = ack;
535 /* Build ACK message and send on connection */
536 msg.header.size = htons (sizeof (msg));
537 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_ACK);
538 msg.ack = htonl (ack);
541 prev_fc->ack_msg = GCC_send_prebuilt_message (&msg.header,
542 GNUNET_MESSAGE_TYPE_CADET_ACK,
543 ack, c, !fwd, GNUNET_YES,
549 * Callback called when a connection queued message is sent.
551 * Calculates the average time and connection packet tracking.
553 * @param cls Closure (ConnectionQueue Handle).
554 * @param c Connection this message was on.
555 * @param sent Was it really sent? (Could have been canceled)
556 * @param type Type of message sent.
557 * @param pid Packet ID, or 0 if not applicable (create, destroy, etc).
558 * @param fwd Was this a FWD going message?
559 * @param size Size of the message.
560 * @param wait Time spent waiting for core (only the time for THIS message)
563 conn_message_sent (void *cls,
564 struct CadetConnection *c, int sent,
565 uint16_t type, uint32_t pid, int fwd, size_t size,
566 struct GNUNET_TIME_Relative wait)
568 struct CadetConnectionPerformance *p;
569 struct CadetFlowControl *fc;
570 struct CadetConnectionQueue *q = cls;
574 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection message_sent\n");
576 fc = fwd ? &c->fwd_fc : &c->bck_fc;
577 LOG (GNUNET_ERROR_TYPE_DEBUG, " %ssent %s %s\n",
578 sent ? "" : "not ", GC_f2s (fwd), GC_m2s (type));
584 LOG (GNUNET_ERROR_TYPE_DEBUG, " calling cont\n");
585 q->cont (q->cont_cls, c, q, type, fwd, size);
589 else if (type == GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED)
591 /* If NULL == q and ENCRYPTED == type, message must have been ch_mngmnt */
600 GNUNET_break (type == GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN ||
601 type == GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
602 LOG (GNUNET_ERROR_TYPE_ERROR, "Message %s sent on NULL connection!\n",
606 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P- %p %u\n", c, c->pending_messages);
607 c->pending_messages--;
608 if (GNUNET_YES == c->destroy && 0 == c->pending_messages)
610 LOG (GNUNET_ERROR_TYPE_DEBUG, "! destroying connection!\n");
614 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
617 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
618 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
619 c->maintenance_q = NULL;
620 /* Don't trigger a keepalive for sent ACKs, only SYN and SYNACKs */
621 if (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE == type || !fwd)
622 schedule_next_keepalive (c, fwd);
625 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
626 if (GNUNET_YES == sent)
628 GNUNET_assert (NULL != q);
629 fc->last_pid_sent = pid; // FIXME
630 GCC_send_ack (c, fwd, GNUNET_NO);
631 connection_reset_timeout (c, fwd);
634 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
635 if (GNUNET_NO == forced)
638 LOG (GNUNET_ERROR_TYPE_DEBUG,
639 "! accounting pid %u\n",
644 LOG (GNUNET_ERROR_TYPE_DEBUG,
645 "! forced, Q_N not accounting pid %u\n",
650 case GNUNET_MESSAGE_TYPE_CADET_KX:
651 if (GNUNET_YES == sent)
652 connection_reset_timeout (c, fwd);
655 case GNUNET_MESSAGE_TYPE_CADET_POLL:
659 case GNUNET_MESSAGE_TYPE_CADET_ACK:
666 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
669 return; /* Only endpoints are interested in timing. */
672 usecsperbyte = ((double) wait.rel_value_us) / size;
673 if (p->size == AVG_MSGS)
675 /* Array is full. Substract oldest value, add new one and store. */
676 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
677 p->usecsperbyte[p->idx] = usecsperbyte;
678 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
682 /* Array not yet full. Add current value to avg and store. */
683 p->usecsperbyte[p->idx] = usecsperbyte;
685 p->avg += p->usecsperbyte[p->idx];
689 p->idx = (p->idx + 1) % AVG_MSGS;
694 * Get the previous hop in a connection
696 * @param c Connection.
698 * @return Previous peer in the connection.
700 static struct CadetPeer *
701 get_prev_hop (const struct CadetConnection *c)
705 LOG (GNUNET_ERROR_TYPE_DEBUG, " get prev hop %s [%u/%u]\n",
706 GCC_2s (c), c->own_pos, c->path->length);
707 if (0 == c->own_pos || c->path->length < 2)
708 id = c->path->peers[0];
710 id = c->path->peers[c->own_pos - 1];
712 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
713 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
715 return GCP_get_short (id);
720 * Get the next hop in a connection
722 * @param c Connection.
724 * @return Next peer in the connection.
726 static struct CadetPeer *
727 get_next_hop (const struct CadetConnection *c)
731 LOG (GNUNET_ERROR_TYPE_DEBUG, " get next hop %s [%u/%u]\n",
732 GCC_2s (c), c->own_pos, c->path->length);
733 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
734 id = c->path->peers[c->path->length - 1];
736 id = c->path->peers[c->own_pos + 1];
738 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
739 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
741 return GCP_get_short (id);
746 * Get the hop in a connection.
748 * @param c Connection.
749 * @param fwd Next hop?
751 * @return Next peer in the connection.
753 static struct CadetPeer *
754 get_hop (struct CadetConnection *c, int fwd)
757 return get_next_hop (c);
758 return get_prev_hop (c);
763 * Is traffic coming from this sender 'FWD' traffic?
765 * @param c Connection to check.
766 * @param sender Peer identity of neighbor.
768 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
769 * the traffic is 'FWD'.
770 * #GNUNET_NO for BCK.
771 * #GNUNET_SYSERR for errors.
774 is_fwd (const struct CadetConnection *c,
775 const struct GNUNET_PeerIdentity *sender)
779 id = GNUNET_PEER_search (sender);
780 if (GCP_get_short_id (get_prev_hop (c)) == id)
783 if (GCP_get_short_id (get_next_hop (c)) == id)
787 return GNUNET_SYSERR;
792 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
793 * or a first CONNECTION_ACK directed to us.
795 * @param connection Connection to confirm.
796 * @param fwd Should we send it FWD? (root->dest)
797 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
800 send_connection_ack (struct CadetConnection *connection, int fwd)
802 struct CadetTunnel *t;
805 LOG (GNUNET_ERROR_TYPE_INFO, "===> {%14s ACK} on connection %s\n",
806 GC_f2s (!fwd), GCC_2s (connection));
807 GCP_queue_add (get_hop (connection, fwd), NULL,
808 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK,
809 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK, 0,
810 sizeof (struct GNUNET_CADET_ConnectionACK),
811 connection, fwd, &conn_message_sent, NULL);
812 connection->pending_messages++;
813 if (CADET_TUNNEL3_NEW == GCT_get_cstate (t))
814 GCT_change_cstate (t, CADET_TUNNEL3_WAITING);
815 if (CADET_CONNECTION_READY != connection->state)
816 connection_change_state (connection, CADET_CONNECTION_SENT);
821 * Send a notification that a connection is broken.
823 * @param c Connection that is broken.
824 * @param id1 Peer that has disconnected.
825 * @param id2 Peer that has disconnected.
826 * @param fwd Direction towards which to send it.
829 send_broken (struct CadetConnection *c,
830 const struct GNUNET_PeerIdentity *id1,
831 const struct GNUNET_PeerIdentity *id2,
834 struct GNUNET_CADET_ConnectionBroken msg;
836 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
837 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
841 GCC_send_prebuilt_message (&msg.header,
842 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN, 0,
843 c, fwd, GNUNET_YES, NULL, NULL);
848 * Send a notification that a connection is broken, when a connection
849 * isn't even known to the local peer.
851 * @param connection_id Connection ID.
852 * @param id1 Peer that has disconnected, probably local peer.
853 * @param id2 Peer that has disconnected can be NULL if unknown.
854 * @param peer Peer to notify (neighbor who sent the connection).
857 send_broken_unknown (const struct GNUNET_CADET_Hash *connection_id,
858 const struct GNUNET_PeerIdentity *id1,
859 const struct GNUNET_PeerIdentity *id2,
860 const struct GNUNET_PeerIdentity *peer_id)
862 struct GNUNET_CADET_ConnectionBroken *msg;
863 struct CadetPeer *neighbor;
865 LOG (GNUNET_ERROR_TYPE_INFO, "===> BROKEN on unknown connection %s\n",
866 GNUNET_h2s (GC_h2hc (connection_id)));
868 msg = GNUNET_new (struct GNUNET_CADET_ConnectionBroken);
869 msg->header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
870 msg->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
871 msg->cid = *connection_id;
876 memset (&msg->peer2, 0, sizeof (msg->peer2));
877 neighbor = GCP_get (peer_id);
878 GCP_queue_add (neighbor, msg,
879 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN,
880 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN, 2,
881 sizeof (struct GNUNET_CADET_ConnectionBroken),
882 NULL, GNUNET_SYSERR, /* connection, fwd */
883 NULL, NULL); /* continuation */
888 * Send keepalive packets for a connection.
890 * @param c Connection to keep alive..
891 * @param fwd Is this a FWD keepalive? (owner -> dest).
894 send_connection_keepalive (struct CadetConnection *c, int fwd)
896 struct GNUNET_MessageHeader msg;
897 struct CadetFlowControl *fc;
899 LOG (GNUNET_ERROR_TYPE_INFO,
900 "keepalive %s for connection %s\n",
901 GC_f2s (fwd), GCC_2s (c));
903 fc = fwd ? &c->fwd_fc : &c->bck_fc;
906 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, traffic in queue\n");
909 GNUNET_STATISTICS_update (stats, "# keepalives sent", 1, GNUNET_NO);
911 GNUNET_assert (NULL != c->t);
912 msg.size = htons (sizeof (msg));
913 msg.type = htons (GNUNET_MESSAGE_TYPE_CADET_KEEPALIVE);
915 GNUNET_assert (NULL ==
916 GCT_send_prebuilt_message (&msg, c->t, c,
917 GNUNET_NO, NULL, NULL));
922 * Send CONNECTION_{CREATE/ACK} packets for a connection.
924 * @param c Connection for which to send the message.
925 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
928 connection_recreate (struct CadetConnection *c, int fwd)
930 LOG (GNUNET_ERROR_TYPE_DEBUG, "sending connection recreate\n");
934 send_connection_ack (c, GNUNET_NO);
939 * Generic connection timer management.
940 * Depending on the role of the peer in the connection will send the
941 * appropriate message (build or keepalive)
943 * @param c Conncetion to maintain.
947 connection_maintain (struct CadetConnection *c, int fwd)
949 if (GNUNET_NO != c->destroy)
952 if (CADET_TUNNEL3_SEARCHING == GCT_get_cstate (c->t))
954 /* TODO DHT GET with RO_BART */
959 case CADET_CONNECTION_NEW:
962 case CADET_CONNECTION_SENT:
963 connection_recreate (c, fwd);
965 case CADET_CONNECTION_READY:
966 send_connection_keepalive (c, fwd);
976 * Keep the connection alive.
978 * @param c Connection to keep alive.
979 * @param fwd Direction.
980 * @param shutdown Are we shutting down? (Don't send traffic)
981 * Non-zero value for true, not necessarily GNUNET_YES.
984 connection_keepalive (struct CadetConnection *c, int fwd, int shutdown)
986 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s keepalive for %s\n",
987 GC_f2s (fwd), GCC_2s (c));
990 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
992 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
994 if (GNUNET_NO != shutdown)
997 connection_maintain (c, fwd);
999 /* Next execution will be scheduled by message_sent */
1004 * Keep the connection alive in the FWD direction.
1006 * @param cls Closure (connection to keepalive).
1007 * @param tc TaskContext.
1010 connection_fwd_keepalive (void *cls,
1011 const struct GNUNET_SCHEDULER_TaskContext *tc)
1013 connection_keepalive ((struct CadetConnection *) cls,
1015 tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN);
1020 * Keep the connection alive in the BCK direction.
1022 * @param cls Closure (connection to keepalive).
1023 * @param tc TaskContext.
1026 connection_bck_keepalive (void *cls,
1027 const struct GNUNET_SCHEDULER_TaskContext *tc)
1029 connection_keepalive ((struct CadetConnection *) cls,
1031 tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN);
1036 * Schedule next keepalive task, taking in consideration
1037 * the connection state and number of retries.
1039 * If the peer is not the origin, do nothing.
1041 * @param c Connection for which to schedule the next keepalive.
1042 * @param fwd Direction for the next keepalive.
1045 schedule_next_keepalive (struct CadetConnection *c, int fwd)
1047 struct GNUNET_TIME_Relative delay;
1048 GNUNET_SCHEDULER_TaskIdentifier *task_id;
1049 GNUNET_SCHEDULER_Task keepalive_task;
1051 if (GNUNET_NO == GCC_is_origin (c, fwd))
1054 /* Calculate delay to use, depending on the state of the connection */
1055 if (CADET_CONNECTION_READY == c->state)
1057 delay = refresh_connection_time;
1061 if (1 > c->create_retry)
1062 c->create_retry = 1;
1063 delay = GNUNET_TIME_relative_multiply (create_connection_time,
1065 if (c->create_retry < 64)
1066 c->create_retry *= 2;
1069 /* Select direction-dependent parameters */
1070 if (GNUNET_YES == fwd)
1072 task_id = &c->fwd_maintenance_task;
1073 keepalive_task = &connection_fwd_keepalive;
1077 task_id = &c->bck_maintenance_task;
1078 keepalive_task = &connection_bck_keepalive;
1081 /* Check that no one scheduled it before us */
1082 if (GNUNET_SCHEDULER_NO_TASK != *task_id)
1084 /* No need for a _break. It can happen for instance when sending a SYNACK
1085 * for a duplicate SYN: the first SYNACK scheduled the task. */
1086 GNUNET_SCHEDULER_cancel (*task_id);
1089 /* Schedule the task */
1090 *task_id = GNUNET_SCHEDULER_add_delayed (delay, keepalive_task, c);
1091 LOG (GNUNET_ERROR_TYPE_DEBUG, "next keepalive in %s\n",
1092 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1097 * @brief Re-initiate traffic on this connection if necessary.
1099 * Check if there is traffic queued towards this peer
1100 * and the core transmit handle is NULL (traffic was stalled).
1101 * If so, call core tmt rdy.
1103 * @param c Connection on which initiate traffic.
1104 * @param fwd Is this about fwd traffic?
1107 connection_unlock_queue (struct CadetConnection *c, int fwd)
1109 struct CadetPeer *peer;
1111 LOG (GNUNET_ERROR_TYPE_DEBUG,
1112 "connection_unlock_queue %s on %s\n",
1113 GC_f2s (fwd), GCC_2s (c));
1115 if (GCC_is_terminal (c, fwd))
1117 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal!\n");
1121 peer = get_hop (c, fwd);
1122 GCP_queue_unlock (peer, c);
1127 * Cancel all transmissions that belong to a certain connection.
1129 * If the connection is scheduled for destruction and no more messages are left,
1130 * the connection will be destroyed by the continuation call.
1132 * @param c Connection which to cancel. Might be destroyed during this call.
1133 * @param fwd Cancel fwd traffic?
1136 connection_cancel_queues (struct CadetConnection *c, int fwd)
1138 struct CadetFlowControl *fc;
1139 struct CadetPeer *peer;
1141 LOG (GNUNET_ERROR_TYPE_DEBUG,
1142 " *** Cancel %s queues for connection %s\n",
1143 GC_f2s (fwd), GCC_2s (c));
1150 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1151 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
1153 GNUNET_SCHEDULER_cancel (fc->poll_task);
1154 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1155 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Cancel POLL in ccq for fc %p\n", fc);
1157 peer = get_hop (c, fwd);
1158 GCP_queue_cancel (peer, c);
1163 * Function called if a connection has been stalled for a while,
1164 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1166 * @param cls Closure (poll ctx).
1167 * @param tc TaskContext.
1170 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
1174 * Callback called when a queued POLL message is sent.
1176 * @param cls Closure (FC).
1177 * @param c Connection this message was on.
1178 * @param q Queue handler this call invalidates.
1179 * @param type Type of message sent.
1180 * @param fwd Was this a FWD going message?
1181 * @param size Size of the message.
1184 poll_sent (void *cls,
1185 struct CadetConnection *c,
1186 struct CadetConnectionQueue *q,
1187 uint16_t type, int fwd, size_t size)
1189 struct CadetFlowControl *fc = cls;
1191 if (2 == c->destroy)
1193 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL canceled on shutdown\n");
1196 LOG (GNUNET_ERROR_TYPE_DEBUG,
1197 " *** POLL sent for , scheduling new one!\n");
1198 fc->poll_msg = NULL;
1199 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1200 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1201 &connection_poll, fc);
1202 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1207 * Function called if a connection has been stalled for a while,
1208 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1210 * @param cls Closure (poll ctx).
1211 * @param tc TaskContext.
1214 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1216 struct CadetFlowControl *fc = cls;
1217 struct GNUNET_CADET_Poll msg;
1218 struct CadetConnection *c;
1220 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1221 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1227 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Polling connection %s %s\n",
1228 GCC_2s (c), fc == &c->fwd_fc ? "FWD" : "BCK");
1230 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_POLL);
1231 msg.header.size = htons (sizeof (msg));
1232 msg.pid = htonl (fc->last_pid_sent);
1233 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** last pid sent: %u!\n", fc->last_pid_sent);
1235 GCC_send_prebuilt_message (&msg.header,
1236 GNUNET_MESSAGE_TYPE_CADET_POLL,
1238 c, fc == &c->fwd_fc, GNUNET_YES,
1244 * Timeout function due to lack of keepalive/traffic from the owner.
1245 * Destroys connection if called.
1247 * @param cls Closure (connection to destroy).
1248 * @param tc TaskContext.
1251 connection_fwd_timeout (void *cls,
1252 const struct GNUNET_SCHEDULER_TaskContext *tc)
1254 struct CadetConnection *c = cls;
1256 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1257 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1260 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s FWD timed out. Destroying.\n",
1262 if (GCC_is_origin (c, GNUNET_YES)) /* If local, leave. */
1273 * Timeout function due to lack of keepalive/traffic from the destination.
1274 * Destroys connection if called.
1276 * @param cls Closure (connection to destroy).
1277 * @param tc TaskContext
1280 connection_bck_timeout (void *cls,
1281 const struct GNUNET_SCHEDULER_TaskContext *tc)
1283 struct CadetConnection *c = cls;
1285 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1286 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1289 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s BCK timed out. Destroying.\n",
1292 if (GCC_is_origin (c, GNUNET_NO)) /* If local, leave. */
1303 * Resets the connection timeout task, some other message has done the
1305 * - For the first peer on the direction this means to send
1306 * a keepalive or a path confirmation message (either create or ACK).
1307 * - For all other peers, this means to destroy the connection,
1308 * due to lack of activity.
1309 * Starts the timeout if no timeout was running (connection just created).
1311 * @param c Connection whose timeout to reset.
1312 * @param fwd Is this forward?
1314 * TODO use heap to improve efficiency of scheduler.
1317 connection_reset_timeout (struct CadetConnection *c, int fwd)
1319 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1321 if (GCC_is_origin (c, fwd)) /* Startpoint */
1323 schedule_next_keepalive (c, fwd);
1325 else /* Relay, endpoint. */
1327 struct GNUNET_TIME_Relative delay;
1328 GNUNET_SCHEDULER_TaskIdentifier *ti;
1329 GNUNET_SCHEDULER_Task f;
1331 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1333 if (GNUNET_SCHEDULER_NO_TASK != *ti)
1334 GNUNET_SCHEDULER_cancel (*ti);
1335 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1336 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1337 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1343 * Add the connection to the list of both neighbors.
1345 * @param c Connection.
1347 * @return #GNUNET_OK if everything went fine
1348 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1351 register_neighbors (struct CadetConnection *c)
1353 struct CadetPeer *next_peer;
1354 struct CadetPeer *prev_peer;
1356 next_peer = get_next_hop (c);
1357 prev_peer = get_prev_hop (c);
1359 LOG (GNUNET_ERROR_TYPE_DEBUG, "register neighbors for connection %s\n",
1361 path_debug (c->path);
1362 LOG (GNUNET_ERROR_TYPE_DEBUG, "own pos %u\n", c->own_pos);
1363 LOG (GNUNET_ERROR_TYPE_DEBUG, "putting connection %s to next peer %p\n",
1364 GCC_2s (c), next_peer);
1365 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n", next_peer, GCP_2s (next_peer));
1366 LOG (GNUNET_ERROR_TYPE_DEBUG, "putting connection %s to prev peer %p\n",
1367 GCC_2s (c), prev_peer);
1368 LOG (GNUNET_ERROR_TYPE_DEBUG, "prev peer %p %s\n", prev_peer, GCP_2s (prev_peer));
1370 if (GNUNET_NO == GCP_is_neighbor (next_peer)
1371 || GNUNET_NO == GCP_is_neighbor (prev_peer))
1373 if (GCC_is_origin (c, GNUNET_YES))
1374 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1375 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1377 LOG (GNUNET_ERROR_TYPE_DEBUG, " register neighbors failed\n");
1378 LOG (GNUNET_ERROR_TYPE_DEBUG, " prev: %s, neighbor?: %d\n",
1379 GCP_2s (prev_peer), GCP_is_neighbor (prev_peer));
1380 LOG (GNUNET_ERROR_TYPE_DEBUG, " next: %s, neighbor?: %d\n",
1381 GCP_2s (next_peer), GCP_is_neighbor (next_peer));
1382 return GNUNET_SYSERR;
1385 GCP_add_connection (next_peer, c);
1386 GCP_add_connection (prev_peer, c);
1393 * Remove the connection from the list of both neighbors.
1395 * @param c Connection.
1398 unregister_neighbors (struct CadetConnection *c)
1400 struct CadetPeer *peer;
1402 peer = get_next_hop (c);
1403 if (GNUNET_OK != GCP_remove_connection (peer, c))
1405 GNUNET_assert (CADET_CONNECTION_NEW == c->state
1406 || CADET_CONNECTION_DESTROYED == c->state);
1407 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate: %u\n", c->state);
1408 if (NULL != c->t) GCT_debug (c->t);
1411 peer = get_prev_hop (c);
1412 if (GNUNET_OK != GCP_remove_connection (peer, c))
1414 GNUNET_assert (CADET_CONNECTION_NEW == c->state
1415 || CADET_CONNECTION_DESTROYED == c->state);
1416 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate: %u\n", c->state);
1417 if (NULL != c->t) GCT_debug (c->t);
1423 * Bind the connection to the peer and the tunnel to that peer.
1425 * If the peer has no tunnel, create one. Update tunnel and connection
1426 * data structres to reflect new status.
1428 * @param c Connection.
1432 add_to_peer (struct CadetConnection *c, struct CadetPeer *peer)
1434 GCP_add_tunnel (peer);
1435 c->t = GCP_get_tunnel (peer);
1436 GCT_add_connection (c->t, c);
1441 * Builds a path from a PeerIdentity array.
1443 * @param peers PeerIdentity array.
1444 * @param size Size of the @c peers array.
1445 * @param own_pos Output parameter: own position in the path.
1447 * @return Fixed and shortened path.
1449 static struct CadetPeerPath *
1450 build_path_from_peer_ids (struct GNUNET_PeerIdentity *peers,
1452 unsigned int *own_pos)
1454 struct CadetPeerPath *path;
1455 GNUNET_PEER_Id shortid;
1458 unsigned int offset;
1461 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating path...\n");
1462 path = path_new (size);
1465 for (i = 0; i < size; i++)
1467 LOG (GNUNET_ERROR_TYPE_DEBUG, " - %u: taking %s\n",
1468 i, GNUNET_i2s (&peers[i]));
1469 shortid = GNUNET_PEER_intern (&peers[i]);
1471 /* Check for loops / duplicates */
1472 for (j = 0; j < i - offset; j++)
1474 if (path->peers[j] == shortid)
1476 LOG (GNUNET_ERROR_TYPE_DEBUG, " already exists at pos %u\n", j);
1478 LOG (GNUNET_ERROR_TYPE_DEBUG, " offset now %u\n", offset);
1479 GNUNET_PEER_change_rc (shortid, -1);
1482 LOG (GNUNET_ERROR_TYPE_DEBUG, " storing at %u\n", i - offset);
1483 path->peers[i - offset] = shortid;
1484 if (path->peers[i - offset] == myid)
1485 *own_pos = i - offset;
1487 path->length -= offset;
1489 if (path->peers[*own_pos] != myid)
1491 /* create path: self not found in path through self */
1492 GNUNET_break_op (0);
1493 path_destroy (path);
1502 * Log receipt of message on stderr (INFO level).
1504 * @param message Message received.
1505 * @param peer Peer who sent the message.
1506 * @param hash Connection ID.
1509 log_message (const struct GNUNET_MessageHeader *message,
1510 const struct GNUNET_PeerIdentity *peer,
1511 const struct GNUNET_CADET_Hash *hash)
1513 LOG (GNUNET_ERROR_TYPE_INFO, "<-- %s on connection %s from %s\n",
1514 GC_m2s (ntohs (message->type)), GNUNET_h2s (GC_h2hc (hash)),
1518 /******************************************************************************/
1519 /******************************** API ***********************************/
1520 /******************************************************************************/
1523 * Core handler for connection creation.
1525 * @param cls Closure (unused).
1526 * @param peer Sender (neighbor).
1527 * @param message Message.
1529 * @return GNUNET_OK to keep the connection open,
1530 * GNUNET_SYSERR to close it (signal serious error)
1533 GCC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
1534 const struct GNUNET_MessageHeader *message)
1536 struct GNUNET_CADET_ConnectionCreate *msg;
1537 struct GNUNET_PeerIdentity *id;
1538 struct GNUNET_CADET_Hash *cid;
1539 struct CadetPeerPath *path;
1540 struct CadetPeer *dest_peer;
1541 struct CadetPeer *orig_peer;
1542 struct CadetConnection *c;
1543 unsigned int own_pos;
1547 size = ntohs (message->size);
1548 if (size < sizeof (struct GNUNET_CADET_ConnectionCreate))
1550 GNUNET_break_op (0);
1554 /* Calculate hops */
1555 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
1556 if (size % sizeof (struct GNUNET_PeerIdentity))
1558 GNUNET_break_op (0);
1561 size /= sizeof (struct GNUNET_PeerIdentity);
1564 GNUNET_break_op (0);
1567 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1569 /* Get parameters */
1570 msg = (struct GNUNET_CADET_ConnectionCreate *) message;
1572 log_message (message, peer, cid);
1573 id = (struct GNUNET_PeerIdentity *) &msg[1];
1574 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
1576 /* Create connection */
1577 c = connection_get (cid);
1580 path = build_path_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
1586 GNUNET_break_op (0);
1587 path_destroy (path);
1590 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1591 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1592 c = GCC_new (cid, NULL, path_duplicate (path), own_pos);
1595 if (path->length - 1 == own_pos)
1597 /* If we are destination, why did the creation fail? */
1601 send_broken_unknown (cid, &my_full_id,
1602 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
1604 path_destroy (path);
1607 GCP_add_path_to_all (path, GNUNET_NO);
1608 connection_reset_timeout (c, GNUNET_YES);
1612 path = path_duplicate (c->path);
1614 if (CADET_CONNECTION_NEW == c->state)
1615 connection_change_state (c, CADET_CONNECTION_SENT);
1617 /* Remember peers */
1618 dest_peer = GCP_get (&id[size - 1]);
1619 orig_peer = GCP_get (&id[0]);
1621 /* Is it a connection to us? */
1622 if (c->own_pos == path->length - 1)
1624 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1625 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
1627 add_to_peer (c, orig_peer);
1628 if (CADET_TUNNEL3_NEW == GCT_get_cstate (c->t))
1629 GCT_change_cstate (c->t, CADET_TUNNEL3_WAITING);
1631 send_connection_ack (c, GNUNET_NO);
1632 if (CADET_CONNECTION_SENT == c->state)
1633 connection_change_state (c, CADET_CONNECTION_ACK);
1637 /* It's for somebody else! Retransmit. */
1638 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
1639 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1640 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
1641 GCC_send_prebuilt_message (message,
1642 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, 0,
1643 c, GNUNET_YES, GNUNET_YES,
1646 path_destroy (path);
1652 * Core handler for path confirmations.
1654 * @param cls closure
1655 * @param message message
1656 * @param peer peer identity this notification is about
1658 * @return GNUNET_OK to keep the connection open,
1659 * GNUNET_SYSERR to close it (signal serious error)
1662 GCC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
1663 const struct GNUNET_MessageHeader *message)
1665 struct GNUNET_CADET_ConnectionACK *msg;
1666 struct CadetConnection *c;
1667 struct CadetPeerPath *p;
1668 struct CadetPeer *pi;
1669 enum CadetConnectionState oldstate;
1672 msg = (struct GNUNET_CADET_ConnectionACK *) message;
1673 log_message (message, peer, &msg->cid);
1674 c = connection_get (&msg->cid);
1677 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1679 LOG (GNUNET_ERROR_TYPE_DEBUG, " don't know the connection!\n");
1680 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
1684 if (GNUNET_NO != c->destroy)
1686 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection being destroyed\n");
1690 oldstate = c->state;
1691 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
1692 pi = GCP_get (peer);
1693 if (get_next_hop (c) == pi)
1695 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
1697 if (CADET_CONNECTION_SENT == oldstate)
1698 connection_change_state (c, CADET_CONNECTION_ACK);
1700 else if (get_prev_hop (c) == pi)
1702 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK\n");
1704 connection_change_state (c, CADET_CONNECTION_READY);
1708 GNUNET_break_op (0);
1712 connection_reset_timeout (c, fwd);
1714 /* Add path to peers? */
1718 GCP_add_path_to_all (p, GNUNET_YES);
1725 /* Message for us as creator? */
1726 if (GCC_is_origin (c, GNUNET_YES))
1728 if (GNUNET_NO != fwd)
1730 GNUNET_break_op (0);
1733 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
1735 /* If just created, cancel the short timeout and start a long one */
1736 if (CADET_CONNECTION_SENT == oldstate)
1737 connection_reset_timeout (c, GNUNET_YES);
1739 /* Change connection state */
1740 connection_change_state (c, CADET_CONNECTION_READY);
1741 send_connection_ack (c, GNUNET_YES);
1743 /* Change tunnel state, trigger KX */
1744 if (CADET_TUNNEL3_WAITING == GCT_get_cstate (c->t))
1745 GCT_change_cstate (c->t, CADET_TUNNEL3_READY);
1750 /* Message for us as destination? */
1751 if (GCC_is_terminal (c, GNUNET_YES))
1753 if (GNUNET_YES != fwd)
1755 GNUNET_break_op (0);
1758 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
1760 /* If just created, cancel the short timeout and start a long one */
1761 if (CADET_CONNECTION_ACK == oldstate)
1762 connection_reset_timeout (c, GNUNET_NO);
1764 /* Change tunnel state */
1765 if (CADET_TUNNEL3_WAITING == GCT_get_cstate (c->t))
1766 GCT_change_cstate (c->t, CADET_TUNNEL3_READY);
1771 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1772 GCC_send_prebuilt_message (message,
1773 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK, 0,
1774 c, fwd, GNUNET_YES, NULL, NULL);
1780 * Core handler for notifications of broken connections.
1782 * @param cls Closure (unused).
1783 * @param id Peer identity of sending neighbor.
1784 * @param message Message.
1786 * @return GNUNET_OK to keep the connection open,
1787 * GNUNET_SYSERR to close it (signal serious error)
1790 GCC_handle_broken (void* cls,
1791 const struct GNUNET_PeerIdentity* id,
1792 const struct GNUNET_MessageHeader* message)
1794 struct GNUNET_CADET_ConnectionBroken *msg;
1795 struct CadetConnection *c;
1798 msg = (struct GNUNET_CADET_ConnectionBroken *) message;
1799 log_message (message, id, &msg->cid);
1800 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1801 GNUNET_i2s (&msg->peer1));
1802 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1803 GNUNET_i2s (&msg->peer2));
1804 c = connection_get (&msg->cid);
1807 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
1811 fwd = is_fwd (c, id);
1812 if (GCC_is_terminal (c, fwd))
1814 struct GNUNET_MessageHeader *out_msg;
1815 struct CadetPeer *neighbor;
1816 struct CadetPeer *endpoint;
1818 neighbor = get_hop (c, !fwd);
1819 endpoint = GCP_get_short (c->path->peers[c->path->length - 1]);
1820 path_invalidate (c->path);
1821 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
1822 c->state = CADET_CONNECTION_DESTROYED;
1823 while (NULL != (out_msg = GCP_connection_pop (neighbor, c)))
1825 GNUNET_assert (NULL ==
1826 GCT_send_prebuilt_message (out_msg, c->t, NULL, GNUNET_YES,
1834 GCC_send_prebuilt_message (message,
1835 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN, 0,
1836 c, fwd, GNUNET_YES, NULL, NULL);
1837 c->destroy = GNUNET_YES;
1838 connection_cancel_queues (c, !fwd);
1847 * Core handler for tunnel destruction
1849 * @param cls Closure (unused).
1850 * @param peer Peer identity of sending neighbor.
1851 * @param message Message.
1853 * @return GNUNET_OK to keep the connection open,
1854 * GNUNET_SYSERR to close it (signal serious error)
1857 GCC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
1858 const struct GNUNET_MessageHeader *message)
1860 struct GNUNET_CADET_ConnectionDestroy *msg;
1861 struct CadetConnection *c;
1864 msg = (struct GNUNET_CADET_ConnectionDestroy *) message;
1865 log_message (message, peer, &msg->cid);
1866 c = connection_get (&msg->cid);
1869 /* Probably already got the message from another path,
1870 * destroyed the tunnel and retransmitted to children.
1873 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1875 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection unknown: already destroyed?\n");
1878 fwd = is_fwd (c, peer);
1879 if (GNUNET_SYSERR == fwd)
1881 GNUNET_break_op (0); /* FIXME */
1884 if (GNUNET_NO == GCC_is_terminal (c, fwd))
1885 GCC_send_prebuilt_message (message,
1886 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY, 0,
1887 c, fwd, GNUNET_YES, NULL, NULL);
1888 else if (0 == c->pending_messages)
1890 LOG (GNUNET_ERROR_TYPE_DEBUG, " directly destroying connection!\n");
1894 c->destroy = GNUNET_YES;
1895 c->state = CADET_CONNECTION_DESTROYED;
1898 GCT_remove_connection (c->t, c);
1906 * Generic handler for cadet network encrypted traffic.
1908 * @param peer Peer identity this notification is about.
1909 * @param msg Encrypted message.
1911 * @return GNUNET_OK to keep the connection open,
1912 * GNUNET_SYSERR to close it (signal serious error)
1915 handle_cadet_encrypted (const struct GNUNET_PeerIdentity *peer,
1916 const struct GNUNET_CADET_Encrypted *msg)
1918 struct CadetConnection *c;
1919 struct CadetPeer *neighbor;
1920 struct CadetFlowControl *fc;
1921 GNUNET_PEER_Id peer_id;
1927 log_message (&msg->header, peer, &msg->cid);
1930 size = ntohs (msg->header.size);
1932 sizeof (struct GNUNET_CADET_Encrypted) +
1933 sizeof (struct GNUNET_MessageHeader))
1935 GNUNET_break_op (0);
1939 /* Check connection */
1940 c = connection_get (&msg->cid);
1943 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1944 LOG (GNUNET_ERROR_TYPE_DEBUG, "enc on unknown connection %s\n",
1945 GNUNET_h2s (GC_h2hc (&msg->cid)));
1946 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
1950 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s\n", GCC_2s (c));
1952 /* Check if origin is as expected */
1953 neighbor = get_prev_hop (c);
1954 peer_id = GNUNET_PEER_search (peer);
1955 if (peer_id == GCP_get_short_id (neighbor))
1961 neighbor = get_next_hop (c);
1962 if (peer_id == GCP_get_short_id (neighbor))
1968 /* Unexpected peer sending traffic on a connection. */
1969 GNUNET_break_op (0);
1975 fc = fwd ? &c->bck_fc : &c->fwd_fc;
1976 pid = ntohl (msg->pid);
1977 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u+)\n",
1978 pid, fc->last_pid_recv + 1);
1979 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
1981 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
1982 GNUNET_break_op (0);
1983 LOG (GNUNET_ERROR_TYPE_WARNING,
1984 "Received PID %u, (prev %u), ACK %u\n",
1985 pid, fc->last_pid_recv, fc->last_ack_sent);
1988 if (GNUNET_NO == GC_is_pid_bigger (pid, fc->last_pid_recv))
1990 GNUNET_STATISTICS_update (stats, "# duplicate PID", 1, GNUNET_NO);
1991 LOG (GNUNET_ERROR_TYPE_DEBUG,
1992 " PID %u not expected (%u+), dropping!\n",
1993 pid, fc->last_pid_recv + 1);
1996 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
1997 connection_change_state (c, CADET_CONNECTION_READY);
1998 connection_reset_timeout (c, fwd);
1999 fc->last_pid_recv = pid;
2001 /* Is this message for us? */
2002 if (GCC_is_terminal (c, fwd))
2004 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2005 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
2009 GNUNET_break (GNUNET_NO != c->destroy);
2012 fc->last_pid_recv = pid;
2013 GCT_handle_encrypted (c->t, msg);
2014 GCC_send_ack (c, fwd, GNUNET_NO);
2018 /* Message not for us: forward to next hop */
2019 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2020 ttl = ntohl (msg->ttl);
2021 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
2024 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
2025 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
2026 GCC_send_ack (c, fwd, GNUNET_NO);
2030 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2031 GCC_send_prebuilt_message (&msg->header,
2032 GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED, 0,
2033 c, fwd, GNUNET_NO, NULL, NULL);
2039 * Generic handler for cadet network encrypted traffic.
2041 * @param peer Peer identity this notification is about.
2042 * @param msg Encrypted message.
2044 * @return GNUNET_OK to keep the connection open,
2045 * GNUNET_SYSERR to close it (signal serious error)
2048 handle_cadet_kx (const struct GNUNET_PeerIdentity *peer,
2049 const struct GNUNET_CADET_KX *msg)
2051 struct CadetConnection *c;
2052 struct CadetPeer *neighbor;
2053 GNUNET_PEER_Id peer_id;
2057 log_message (&msg->header, peer, &msg->cid);
2060 size = ntohs (msg->header.size);
2062 sizeof (struct GNUNET_CADET_KX) +
2063 sizeof (struct GNUNET_MessageHeader))
2065 GNUNET_break_op (0);
2069 /* Check connection */
2070 c = connection_get (&msg->cid);
2073 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
2074 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx on unknown connection %s\n",
2075 GNUNET_h2s (GC_h2hc (&msg->cid)));
2076 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2079 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n", GCC_2s (c));
2081 /* Check if origin is as expected */
2082 neighbor = get_prev_hop (c);
2083 peer_id = GNUNET_PEER_search (peer);
2084 if (peer_id == GCP_get_short_id (neighbor))
2090 neighbor = get_next_hop (c);
2091 if (peer_id == GCP_get_short_id (neighbor))
2097 /* Unexpected peer sending traffic on a connection. */
2098 GNUNET_break_op (0);
2103 /* Count as connection confirmation. */
2104 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2106 connection_change_state (c, CADET_CONNECTION_READY);
2109 if (CADET_TUNNEL3_WAITING == GCT_get_cstate (c->t))
2110 GCT_change_cstate (c->t, CADET_TUNNEL3_READY);
2113 connection_reset_timeout (c, fwd);
2115 /* Is this message for us? */
2116 if (GCC_is_terminal (c, fwd))
2118 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2119 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
2125 GCT_handle_kx (c->t, &msg[1].header);
2129 /* Message not for us: forward to next hop */
2130 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2131 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2132 GCC_send_prebuilt_message (&msg->header, GNUNET_MESSAGE_TYPE_CADET_KX, 0,
2133 c, fwd, GNUNET_NO, NULL, NULL);
2140 * Core handler for encrypted cadet network traffic (channel mgmt, data).
2142 * @param cls Closure (unused).
2143 * @param message Message received.
2144 * @param peer Peer who sent the message.
2146 * @return GNUNET_OK to keep the connection open,
2147 * GNUNET_SYSERR to close it (signal serious error)
2150 GCC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
2151 const struct GNUNET_MessageHeader *message)
2153 return handle_cadet_encrypted (peer,
2154 (struct GNUNET_CADET_Encrypted *)message);
2159 * Core handler for key exchange traffic (ephemeral key, ping, pong).
2161 * @param cls Closure (unused).
2162 * @param message Message received.
2163 * @param peer Peer who sent the message.
2165 * @return GNUNET_OK to keep the connection open,
2166 * GNUNET_SYSERR to close it (signal serious error)
2169 GCC_handle_kx (void *cls, const struct GNUNET_PeerIdentity *peer,
2170 const struct GNUNET_MessageHeader *message)
2172 return handle_cadet_kx (peer,
2173 (struct GNUNET_CADET_KX *) message);
2178 * Core handler for cadet network traffic point-to-point acks.
2180 * @param cls closure
2181 * @param message message
2182 * @param peer peer identity this notification is about
2184 * @return GNUNET_OK to keep the connection open,
2185 * GNUNET_SYSERR to close it (signal serious error)
2188 GCC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
2189 const struct GNUNET_MessageHeader *message)
2191 struct GNUNET_CADET_ACK *msg;
2192 struct CadetConnection *c;
2193 struct CadetFlowControl *fc;
2198 msg = (struct GNUNET_CADET_ACK *) message;
2199 log_message (message, peer, &msg->cid);
2200 c = connection_get (&msg->cid);
2203 GNUNET_STATISTICS_update (stats, "# ack on unknown connection", 1,
2205 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2209 /* Is this a forward or backward ACK? */
2210 id = GNUNET_PEER_search (peer);
2211 if (GCP_get_short_id (get_next_hop (c)) == id)
2213 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
2217 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2219 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
2225 GNUNET_break_op (0);
2229 ack = ntohl (msg->ack);
2230 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u (was %u)\n",
2231 ack, fc->last_ack_recv);
2232 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2233 fc->last_ack_recv = ack;
2235 /* Cancel polling if the ACK is big enough. */
2236 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task &&
2237 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2239 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2240 GNUNET_SCHEDULER_cancel (fc->poll_task);
2241 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2242 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2245 connection_unlock_queue (c, fwd);
2252 * Core handler for cadet network traffic point-to-point ack polls.
2254 * @param cls closure
2255 * @param message message
2256 * @param peer peer identity this notification is about
2258 * @return GNUNET_OK to keep the connection open,
2259 * GNUNET_SYSERR to close it (signal serious error)
2262 GCC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
2263 const struct GNUNET_MessageHeader *message)
2265 struct GNUNET_CADET_Poll *msg;
2266 struct CadetConnection *c;
2267 struct CadetFlowControl *fc;
2272 msg = (struct GNUNET_CADET_Poll *) message;
2273 log_message (message, peer, &msg->cid);
2274 c = connection_get (&msg->cid);
2277 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2279 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL message on unknown connection %s!\n",
2280 GNUNET_h2s (GC_h2hc (&msg->cid)));
2281 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2285 /* Is this a forward or backward ACK?
2286 * Note: a poll should never be needed in a loopback case,
2287 * since there is no possiblility of packet loss there, so
2288 * this way of discerining FWD/BCK should not be a problem.
2290 id = GNUNET_PEER_search (peer);
2291 if (GCP_get_short_id (get_next_hop (c)) == id)
2293 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2296 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2298 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2303 GNUNET_break_op (0);
2307 pid = ntohl (msg->pid);
2308 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2309 fc->last_pid_recv = pid;
2310 fwd = fc == &c->bck_fc;
2311 GCC_send_ack (c, fwd, GNUNET_YES);
2318 * Send an ACK on the appropriate connection/channel, depending on
2319 * the direction and the position of the peer.
2321 * @param c Which connection to send the hop-by-hop ACK.
2322 * @param fwd Is this a fwd ACK? (will go dest->root).
2323 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2326 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
2328 unsigned int buffer;
2330 LOG (GNUNET_ERROR_TYPE_DEBUG,
2331 "GMC send %s ACK on %s\n",
2332 GC_f2s (fwd), GCC_2s (c));
2340 if (GNUNET_NO != c->destroy)
2342 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2346 /* Get available buffer space */
2347 if (GCC_is_terminal (c, fwd))
2349 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2350 buffer = GCT_get_channels_buffer (c->t);
2354 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2355 buffer = GCC_get_buffer (c, fwd);
2357 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2358 if (0 == buffer && GNUNET_NO == force)
2361 /* Send available buffer space */
2362 if (GCC_is_origin (c, fwd))
2364 GNUNET_assert (NULL != c->t);
2365 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2366 GCT_unchoke_channels (c->t);
2370 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2371 send_ack (c, buffer, fwd, force);
2377 * Initialize the connections subsystem
2379 * @param c Configuration handle.
2382 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2384 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2386 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2389 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2390 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2391 GNUNET_SCHEDULER_shutdown ();
2396 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2399 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2400 "CADET", "MAX_CONNECTIONS", "MISSING");
2401 GNUNET_SCHEDULER_shutdown ();
2406 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2407 &refresh_connection_time))
2409 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2410 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2411 GNUNET_SCHEDULER_shutdown ();
2414 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2415 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2420 * Destroy each connection on shutdown.
2422 * @param cls Closure (unused).
2423 * @param key Current key code (CID, unused).
2424 * @param value Value in the hash map (connection)
2426 * @return #GNUNET_YES, because we should continue to iterate,
2429 shutdown_iterator (void *cls,
2430 const struct GNUNET_HashCode *key,
2433 struct CadetConnection *c = value;
2441 * Shut down the connections subsystem.
2446 GNUNET_CONTAINER_multihashmap_iterate (connections, &shutdown_iterator, NULL);
2447 GNUNET_CONTAINER_multihashmap_destroy (connections);
2452 struct CadetConnection *
2453 GCC_new (const struct GNUNET_CADET_Hash *cid,
2454 struct CadetTunnel *t,
2455 struct CadetPeerPath *p,
2456 unsigned int own_pos)
2458 struct CadetConnection *c;
2460 c = GNUNET_new (struct CadetConnection);
2462 GNUNET_assert (GNUNET_OK ==
2463 GNUNET_CONTAINER_multihashmap_put (connections,
2465 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2466 fc_init (&c->fwd_fc);
2467 fc_init (&c->bck_fc);
2472 GNUNET_assert (own_pos <= p->length - 1);
2473 c->own_pos = own_pos;
2477 if (GNUNET_OK != register_neighbors (c))
2481 path_invalidate (c->path);
2494 GCC_destroy (struct CadetConnection *c)
2502 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
2503 return; /* -> message_sent -> GCC_destroy. Don't loop. */
2506 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying connection %s\n", GCC_2s (c));
2507 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc's f: %p, b: %p\n",
2508 &c->fwd_fc, &c->bck_fc);
2509 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2510 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2512 /* Cancel all traffic */
2513 if (NULL != c->path)
2515 connection_cancel_queues (c, GNUNET_YES);
2516 connection_cancel_queues (c, GNUNET_NO);
2517 unregister_neighbors (c);
2520 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2521 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2523 /* Cancel maintainance task (keepalive/timeout) */
2524 if (NULL != c->fwd_fc.poll_msg)
2526 GCC_cancel (c->fwd_fc.poll_msg);
2527 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg FWD canceled\n");
2529 if (NULL != c->bck_fc.poll_msg)
2531 GCC_cancel (c->bck_fc.poll_msg);
2532 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg BCK canceled\n");
2535 /* Delete from tunnel */
2537 GCT_remove_connection (c->t, c);
2539 if (GNUNET_NO == GCC_is_origin (c, GNUNET_YES) && NULL != c->path)
2540 path_destroy (c->path);
2541 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_maintenance_task)
2542 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2543 if (GNUNET_SCHEDULER_NO_TASK != c->bck_maintenance_task)
2544 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2545 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_fc.poll_task)
2547 GNUNET_SCHEDULER_cancel (c->fwd_fc.poll_task);
2548 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL FWD canceled\n");
2550 if (GNUNET_SCHEDULER_NO_TASK != c->bck_fc.poll_task)
2552 GNUNET_SCHEDULER_cancel (c->bck_fc.poll_task);
2553 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL BCK canceled\n");
2556 GNUNET_break (GNUNET_YES ==
2557 GNUNET_CONTAINER_multihashmap_remove (connections,
2560 GNUNET_STATISTICS_update (stats, "# connections", -1, GNUNET_NO);
2565 * Get the connection ID.
2567 * @param c Connection to get the ID from.
2569 * @return ID of the connection.
2571 const struct GNUNET_CADET_Hash *
2572 GCC_get_id (const struct CadetConnection *c)
2579 * Get the connection ID.
2581 * @param c Connection to get the ID from.
2583 * @return ID of the connection.
2585 const struct GNUNET_HashCode *
2586 GCC_get_h (const struct CadetConnection *c)
2588 return GC_h2hc (&c->id);
2593 * Get the connection path.
2595 * @param c Connection to get the path from.
2597 * @return path used by the connection.
2599 const struct CadetPeerPath *
2600 GCC_get_path (const struct CadetConnection *c)
2602 if (GNUNET_NO == c->destroy)
2609 * Get the connection state.
2611 * @param c Connection to get the state from.
2613 * @return state of the connection.
2615 enum CadetConnectionState
2616 GCC_get_state (const struct CadetConnection *c)
2622 * Get the connection tunnel.
2624 * @param c Connection to get the tunnel from.
2626 * @return tunnel of the connection.
2628 struct CadetTunnel *
2629 GCC_get_tunnel (const struct CadetConnection *c)
2636 * Get free buffer space in a connection.
2638 * @param c Connection.
2639 * @param fwd Is query about FWD traffic?
2641 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2644 GCC_get_buffer (struct CadetConnection *c, int fwd)
2646 struct CadetFlowControl *fc;
2648 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2650 return (fc->queue_max - fc->queue_n);
2654 * Get how many messages have we allowed to send to us from a direction.
2656 * @param c Connection.
2657 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2659 * @return last_ack_sent - last_pid_recv
2662 GCC_get_allowed (struct CadetConnection *c, int fwd)
2664 struct CadetFlowControl *fc;
2666 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2667 if (GC_is_pid_bigger(fc->last_pid_recv, fc->last_ack_sent))
2671 return (fc->last_ack_sent - fc->last_pid_recv);
2675 * Get messages queued in a connection.
2677 * @param c Connection.
2678 * @param fwd Is query about FWD traffic?
2680 * @return Number of messages queued.
2683 GCC_get_qn (struct CadetConnection *c, int fwd)
2685 struct CadetFlowControl *fc;
2687 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2694 * Get next PID to use.
2696 * @param c Connection.
2697 * @param fwd Is query about FWD traffic?
2699 * @return Last PID used + 1.
2702 GCC_get_pid (struct CadetConnection *c, int fwd)
2704 struct CadetFlowControl *fc;
2706 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2708 return fc->last_pid_sent + 1;
2713 * Allow the connection to advertise a buffer of the given size.
2715 * The connection will send an @c fwd ACK message (so: in direction !fwd)
2716 * allowing up to last_pid_recv + buffer.
2718 * @param c Connection.
2719 * @param buffer How many more messages the connection can accept.
2720 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
2723 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
2725 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
2726 GCC_2s (c), buffer, GC_f2s (fwd));
2727 send_ack (c, buffer, fwd, GNUNET_NO);
2732 * Notify other peers on a connection of a broken link. Mark connections
2733 * to destroy after all traffic has been sent.
2735 * @param c Connection on which there has been a disconnection.
2736 * @param peer Peer that disconnected.
2739 GCC_notify_broken (struct CadetConnection *c,
2740 struct CadetPeer *peer)
2744 LOG (GNUNET_ERROR_TYPE_DEBUG,
2745 " notify broken on %s due to %s disconnect\n",
2746 GCC_2s (c), GCP_2s (peer));
2748 fwd = peer == get_prev_hop (c);
2750 if (GNUNET_YES == GCC_is_terminal (c, fwd))
2752 /* Local shutdown, no one to notify about this. */
2756 if (GNUNET_NO == c->destroy)
2757 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
2759 /* Connection will have at least one pending message
2760 * (the one we just scheduled), so no point in checking whether to
2761 * destroy immediately. */
2762 c->destroy = GNUNET_YES;
2763 c->state = CADET_CONNECTION_DESTROYED;
2766 * Cancel all queues, if no message is left, connection will be destroyed.
2768 connection_cancel_queues (c, !fwd);
2775 * Is this peer the first one on the connection?
2777 * @param c Connection.
2778 * @param fwd Is this about fwd traffic?
2780 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
2783 GCC_is_origin (struct CadetConnection *c, int fwd)
2785 if (!fwd && c->path->length - 1 == c->own_pos )
2787 if (fwd && 0 == c->own_pos)
2794 * Is this peer the last one on the connection?
2796 * @param c Connection.
2797 * @param fwd Is this about fwd traffic?
2798 * Note that the ROOT is the terminal for BCK traffic!
2800 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
2803 GCC_is_terminal (struct CadetConnection *c, int fwd)
2805 return GCC_is_origin (c, !fwd);
2810 * See if we are allowed to send by the next hop in the given direction.
2812 * @param c Connection.
2813 * @param fwd Is this about fwd traffic?
2815 * @return #GNUNET_YES in case it's OK to send.
2818 GCC_is_sendable (struct CadetConnection *c, int fwd)
2820 struct CadetFlowControl *fc;
2822 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking sendability of %s traffic on %s\n",
2823 GC_f2s (fwd), GCC_2s (c));
2829 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2830 LOG (GNUNET_ERROR_TYPE_DEBUG,
2831 " last ack recv: %u, last pid sent: %u\n",
2832 fc->last_ack_recv, fc->last_pid_sent);
2833 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2835 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
2838 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
2844 * Check if this connection is a direct one (never trim a direct connection).
2846 * @param c Connection.
2848 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
2851 GCC_is_direct (struct CadetConnection *c)
2853 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
2857 * Sends an already built message on a connection, properly registering
2858 * all used resources.
2860 * @param message Message to send. Function makes a copy of it.
2861 * If message is not hop-by-hop, decrements TTL of copy.
2862 * @param payload_type Type of payload, in case the message is encrypted.
2863 * @param c Connection on which this message is transmitted.
2864 * @param fwd Is this a fwd message?
2865 * @param force Force the connection to accept the message (buffer overfill).
2866 * @param cont Continuation called once message is sent. Can be NULL.
2867 * @param cont_cls Closure for @c cont.
2869 * @return Handle to cancel the message before it's sent.
2870 * NULL on error or if @c cont is NULL.
2871 * Invalid on @c cont call.
2873 struct CadetConnectionQueue *
2874 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2875 uint16_t payload_type, uint32_t payload_id,
2876 struct CadetConnection *c, int fwd, int force,
2877 GCC_sent cont, void *cont_cls)
2879 struct CadetFlowControl *fc;
2880 struct CadetConnectionQueue *q;
2886 size = ntohs (message->size);
2887 data = GNUNET_malloc (size);
2888 memcpy (data, message, size);
2889 type = ntohs (message->type);
2890 LOG (GNUNET_ERROR_TYPE_INFO, "--> %s (%s %u) on connection %s (%u bytes)\n",
2891 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), size);
2893 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2894 droppable = GNUNET_NO == force;
2897 struct GNUNET_CADET_Encrypted *emsg;
2898 struct GNUNET_CADET_KX *kmsg;
2899 struct GNUNET_CADET_ACK *amsg;
2900 struct GNUNET_CADET_Poll *pmsg;
2901 struct GNUNET_CADET_ConnectionDestroy *dmsg;
2902 struct GNUNET_CADET_ConnectionBroken *bmsg;
2905 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
2906 emsg = (struct GNUNET_CADET_Encrypted *) data;
2907 ttl = ntohl (emsg->ttl);
2910 GNUNET_break_op (0);
2915 emsg->ttl = htonl (ttl - 1);
2916 emsg->pid = htonl (0);
2917 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
2918 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
2919 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
2920 if (GNUNET_YES == droppable)
2926 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
2928 if (GC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
2930 GCC_start_poll (c, fwd);
2934 case GNUNET_MESSAGE_TYPE_CADET_KX:
2935 kmsg = (struct GNUNET_CADET_KX *) data;
2939 case GNUNET_MESSAGE_TYPE_CADET_ACK:
2940 amsg = (struct GNUNET_CADET_ACK *) data;
2942 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
2943 droppable = GNUNET_NO;
2946 case GNUNET_MESSAGE_TYPE_CADET_POLL:
2947 pmsg = (struct GNUNET_CADET_Poll *) data;
2949 LOG (GNUNET_ERROR_TYPE_DEBUG, " poll %u\n", ntohl (pmsg->pid));
2950 droppable = GNUNET_NO;
2953 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
2954 dmsg = (struct GNUNET_CADET_ConnectionDestroy *) data;
2958 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
2959 bmsg = (struct GNUNET_CADET_ConnectionBroken *) data;
2963 case GNUNET_MESSAGE_TYPE_CADET_KEEPALIVE:
2966 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
2967 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
2976 if (fc->queue_n > fc->queue_max && droppable)
2978 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
2981 LOG (GNUNET_ERROR_TYPE_DEBUG,
2982 "queue full: %u/%u\n",
2983 fc->queue_n, fc->queue_max);
2984 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
2989 return NULL; /* Drop this message */
2992 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u\n", c, c->pending_messages);
2993 // c->pending_messages++;
2995 q = GNUNET_new (struct CadetConnectionQueue);
2996 q->forced = !droppable;
2997 q->q = GCP_queue_add (get_hop (c, fwd), data, type, payload_type, payload_id,
2998 size, c, fwd, &conn_message_sent, q);
3001 LOG (GNUNET_ERROR_TYPE_DEBUG, "WARNING dropping msg on %s\n", GCC_2s (c));
3007 q->cont_cls = cont_cls;
3008 return (NULL == cont) ? NULL : q;
3013 * Cancel a previously sent message while it's in the queue.
3015 * ONLY can be called before the continuation given to the send function
3016 * is called. Once the continuation is called, the message is no longer in the
3019 * @param q Handle to the queue.
3022 GCC_cancel (struct CadetConnectionQueue *q)
3024 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GMC cancel message\n");
3026 /* queue destroy calls message_sent, which calls q->cont and frees q */
3027 GCP_queue_destroy (q->q, GNUNET_YES, GNUNET_NO, 0);
3032 * Sends a CREATE CONNECTION message for a path to a peer.
3033 * Changes the connection and tunnel states if necessary.
3035 * @param connection Connection to create.
3038 GCC_send_create (struct CadetConnection *connection)
3040 enum CadetTunnelCState state;
3043 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3044 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
3046 LOG (GNUNET_ERROR_TYPE_INFO, "===> %s on connection %s (%u bytes)\n",
3047 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE),
3048 GCC_2s (connection), size);
3049 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3050 connection, connection->pending_messages);
3051 connection->pending_messages++;
3053 connection->maintenance_q =
3054 GCP_queue_add (get_next_hop (connection), NULL,
3055 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE,
3056 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, 0,
3057 size, connection, GNUNET_YES, &conn_message_sent, NULL);
3059 state = GCT_get_cstate (connection->t);
3060 if (CADET_TUNNEL3_SEARCHING == state || CADET_TUNNEL3_NEW == state)
3061 GCT_change_cstate (connection->t, CADET_TUNNEL3_WAITING);
3062 if (CADET_CONNECTION_NEW == connection->state)
3063 connection_change_state (connection, CADET_CONNECTION_SENT);
3068 * Send a message to all peers in this connection that the connection
3069 * is no longer valid.
3071 * If some peer should not receive the message, it should be zero'ed out
3072 * before calling this function.
3074 * @param c The connection whose peers to notify.
3077 GCC_send_destroy (struct CadetConnection *c)
3079 struct GNUNET_CADET_ConnectionDestroy msg;
3081 if (GNUNET_YES == c->destroy)
3084 msg.header.size = htons (sizeof (msg));
3085 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);;
3087 LOG (GNUNET_ERROR_TYPE_DEBUG,
3088 " sending connection destroy for connection %s\n",
3091 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3092 GCC_send_prebuilt_message (&msg.header,
3093 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY, 0,
3094 c, GNUNET_YES, GNUNET_YES, NULL, NULL);
3095 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3096 GCC_send_prebuilt_message (&msg.header,
3097 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY, 0,
3098 c, GNUNET_NO, GNUNET_YES, NULL, NULL);
3099 c->destroy = GNUNET_YES;
3100 c->state = CADET_CONNECTION_DESTROYED;
3105 * @brief Start a polling timer for the connection.
3107 * When a neighbor does not accept more traffic on the connection it could be
3108 * caused by a simple congestion or by a lost ACK. Polling enables to check
3109 * for the lastest ACK status for a connection.
3111 * @param c Connection.
3112 * @param fwd Should we poll in the FWD direction?
3115 GCC_start_poll (struct CadetConnection *c, int fwd)
3117 struct CadetFlowControl *fc;
3119 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3120 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL %s requested\n",
3122 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task || NULL != fc->poll_msg)
3124 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** not needed (%u, %p)\n",
3125 fc->poll_task, fc->poll_msg);
3128 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL started on request\n");
3129 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
3136 * @brief Stop polling a connection for ACKs.
3138 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3140 * @param c Connection.
3141 * @param fwd Should we stop the poll in the FWD direction?
3144 GCC_stop_poll (struct CadetConnection *c, int fwd)
3146 struct CadetFlowControl *fc;
3148 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3149 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
3151 GNUNET_SCHEDULER_cancel (fc->poll_task);
3152 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
3157 * Get a (static) string for a connection.
3159 * @param c Connection.
3162 GCC_2s (const struct CadetConnection *c)
3169 static char buf[128];
3171 sprintf (buf, "%s (->%s)",
3172 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3175 return GNUNET_h2s (GC_h2hc (&c->id));