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__)
41 #define LOG2(level, ...) GNUNET_log_from_nocheck(level,"cadet-con",__VA_ARGS__)
44 #define CADET_MAX_POLL_TIME GNUNET_TIME_relative_multiply (\
45 GNUNET_TIME_UNIT_MINUTES,\
50 /******************************************************************************/
51 /******************************** STRUCTS **********************************/
52 /******************************************************************************/
55 * Struct to encapsulate all the Flow Control information to a peer to which
56 * we are directly connected (on a core level).
58 struct CadetFlowControl
61 * Connection this controls.
63 struct CadetConnection *c;
66 * How many messages are in the queue on this connection.
71 * How many messages do we accept in the queue.
73 unsigned int queue_max;
76 * ID of the last packet sent towards the peer.
78 uint32_t last_pid_sent;
81 * ID of the last packet received from the peer.
83 uint32_t last_pid_recv;
86 * Last ACK sent to the peer (peer can't send more than this PID).
88 uint32_t last_ack_sent;
91 * Last ACK sent towards the origin (for traffic towards leaf node).
93 uint32_t last_ack_recv;
96 * Task to poll the peer in case of a lost ACK causes stall.
98 GNUNET_SCHEDULER_TaskIdentifier poll_task;
101 * How frequently to poll for ACKs.
103 struct GNUNET_TIME_Relative poll_time;
106 * Queued poll message, to cancel if not necessary anymore (got ACK).
108 struct CadetConnectionQueue *poll_msg;
111 * Queued poll message, to cancel if not necessary anymore (got ACK).
113 struct CadetConnectionQueue *ack_msg;
117 * Keep a record of the last messages sent on this connection.
119 struct CadetConnectionPerformance
122 * Circular buffer for storing measurements.
124 double usecsperbyte[AVG_MSGS];
127 * Running average of @c usecsperbyte.
132 * How many values of @c usecsperbyte are valid.
137 * Index of the next "free" position in @c usecsperbyte.
144 * Struct containing all information regarding a connection to a peer.
146 struct CadetConnection
149 * Tunnel this connection is part of.
151 struct CadetTunnel *t;
154 * Flow control information for traffic fwd.
156 struct CadetFlowControl fwd_fc;
159 * Flow control information for traffic bck.
161 struct CadetFlowControl bck_fc;
164 * Measure connection performance on the endpoint.
166 struct CadetConnectionPerformance *perf;
169 * ID of the connection.
171 struct GNUNET_CADET_Hash id;
174 * State of the connection.
176 enum CadetConnectionState state;
179 * Path being used for the tunnel. At the origin of the connection
180 * it's a pointer to the destination's path pool, otherwise just a copy.
182 struct CadetPeerPath *path;
185 * Position of the local peer in the path.
187 unsigned int own_pos;
190 * Task to keep the used paths alive at the owner,
191 * time tunnel out on all the other peers.
193 GNUNET_SCHEDULER_TaskIdentifier fwd_maintenance_task;
196 * Task to keep the used paths alive at the destination,
197 * time tunnel out on all the other peers.
199 GNUNET_SCHEDULER_TaskIdentifier bck_maintenance_task;
202 * Queue handle for maintainance traffic. One handle for FWD and BCK since
203 * one peer never needs to maintain both directions (no loopback connections).
205 struct CadetPeerQueue *maintenance_q;
208 * Counter to do exponential backoff when creating a connection (max 64).
210 unsigned short create_retry;
213 * Pending message count.
215 int pending_messages;
218 * Destroy flag: if true, destroy on last message.
224 * Handle for messages queued but not yet sent.
226 struct CadetConnectionQueue
229 * Peer queue handle, to cancel if necessary.
231 struct CadetPeerQueue *q;
234 * Was this a forced message? (Do not account for it)
239 * Continuation to call once sent.
244 * Closure for @c cont.
249 /******************************************************************************/
250 /******************************* GLOBALS ***********************************/
251 /******************************************************************************/
254 * Global handle to the statistics service.
256 extern struct GNUNET_STATISTICS_Handle *stats;
259 * Local peer own ID (memory efficient handle).
261 extern GNUNET_PEER_Id myid;
264 * Local peer own ID (full value).
266 extern struct GNUNET_PeerIdentity my_full_id;
269 * Connections known, indexed by cid (CadetConnection).
271 static struct GNUNET_CONTAINER_MultiHashMap *connections;
274 * How many connections are we willing to maintain.
275 * Local connections are always allowed, even if there are more connections than max.
277 static unsigned long long max_connections;
280 * How many messages *in total* are we willing to queue, divide by number of
281 * connections to get connection queue size.
283 static unsigned long long max_msgs_queue;
286 * How often to send path keepalives. Paths timeout after 4 missed.
288 static struct GNUNET_TIME_Relative refresh_connection_time;
291 * How often to send path create / ACKs.
293 static struct GNUNET_TIME_Relative create_connection_time;
296 /******************************************************************************/
297 /******************************** STATIC ***********************************/
298 /******************************************************************************/
300 #if 0 // avoid compiler warning for unused static function
302 fc_debug (struct CadetFlowControl *fc)
304 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
305 fc->last_pid_recv, fc->last_ack_sent);
306 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
307 fc->last_pid_sent, fc->last_ack_recv);
308 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
309 fc->queue_n, fc->queue_max);
313 connection_debug (struct CadetConnection *c)
317 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CONNECTION ***\n");
320 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
321 peer2s (c->t->peer), GCC_2s (c));
322 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
323 c->state, c->pending_messages);
324 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
325 fc_debug (&c->fwd_fc);
326 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
327 fc_debug (&c->bck_fc);
333 * Schedule next keepalive task, taking in consideration
334 * the connection state and number of retries.
336 * @param c Connection for which to schedule the next keepalive.
337 * @param fwd Direction for the next keepalive.
340 schedule_next_keepalive (struct CadetConnection *c, int fwd);
344 * Resets the connection timeout task, some other message has done the
346 * - For the first peer on the direction this means to send
347 * a keepalive or a path confirmation message (either create or ACK).
348 * - For all other peers, this means to destroy the connection,
349 * due to lack of activity.
350 * Starts the timeout if no timeout was running (connection just created).
352 * @param c Connection whose timeout to reset.
353 * @param fwd Is this forward?
356 connection_reset_timeout (struct CadetConnection *c, int fwd);
360 * Get string description for tunnel state. Reentrant.
362 * @param s Tunnel state.
364 * @return String representation.
367 GCC_state2s (enum CadetConnectionState s)
371 case CADET_CONNECTION_NEW:
372 return "CADET_CONNECTION_NEW";
373 case CADET_CONNECTION_SENT:
374 return "CADET_CONNECTION_SENT";
375 case CADET_CONNECTION_ACK:
376 return "CADET_CONNECTION_ACK";
377 case CADET_CONNECTION_READY:
378 return "CADET_CONNECTION_READY";
379 case CADET_CONNECTION_DESTROYED:
380 return "CADET_CONNECTION_DESTROYED";
381 case CADET_CONNECTION_BROKEN:
382 return "CADET_CONNECTION_BROKEN";
385 LOG (GNUNET_ERROR_TYPE_ERROR, " conn state %u unknown!\n", s);
386 return "CADET_CONNECTION_STATE_ERROR";
392 * Initialize a Flow Control structure to the initial state.
394 * @param fc Flow Control structure to initialize.
397 fc_init (struct CadetFlowControl *fc)
399 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
400 fc->last_pid_recv = (uint32_t) -1;
401 fc->last_ack_sent = (uint32_t) 0;
402 fc->last_ack_recv = (uint32_t) 0;
403 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
404 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
406 fc->queue_max = (max_msgs_queue / max_connections) + 1;
413 * @param cid Connection ID.
415 static struct CadetConnection *
416 connection_get (const struct GNUNET_CADET_Hash *cid)
418 return GNUNET_CONTAINER_multihashmap_get (connections, GC_h2hc (cid));
423 connection_change_state (struct CadetConnection* c,
424 enum CadetConnectionState state)
426 LOG (GNUNET_ERROR_TYPE_DEBUG,
427 "Connection %s state %s -> %s\n",
428 GCC_2s (c), GCC_state2s (c->state), GCC_state2s (state));
429 if (CADET_CONNECTION_DESTROYED <= c->state) /* Destroyed or broken. */
431 LOG (GNUNET_ERROR_TYPE_DEBUG, "state not changing anymore\n");
435 if (CADET_CONNECTION_READY == state)
441 * Callback called when a queued ACK message is sent.
443 * @param cls Closure (FC).
444 * @param c Connection this message was on.
445 * @param q Queue handler this call invalidates.
446 * @param type Type of message sent.
447 * @param fwd Was this a FWD going message?
448 * @param size Size of the message.
452 struct CadetConnection *c,
453 struct CadetConnectionQueue *q,
454 uint16_t type, int fwd, size_t size)
456 struct CadetFlowControl *fc = cls;
463 * Send an ACK on the connection, informing the predecessor about
464 * the available buffer space. Should not be called in case the peer
465 * is origin (no predecessor) in the @c fwd direction.
467 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
468 * the ACK itself goes "back" (dest->root).
470 * @param c Connection on which to send the ACK.
471 * @param buffer How much space free to advertise?
472 * @param fwd Is this FWD ACK? (Going dest -> root)
473 * @param force Don't optimize out.
476 send_ack (struct CadetConnection *c, unsigned int buffer, int fwd, int force)
478 struct CadetFlowControl *next_fc;
479 struct CadetFlowControl *prev_fc;
480 struct GNUNET_CADET_ACK msg;
484 /* If origin, there is no connection to send ACKs. Wrong function! */
485 if (GCC_is_origin (c, fwd))
487 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection %s is origin in %s\n",
488 GCC_2s (c), GC_f2s (fwd));
493 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
494 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
496 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection send %s ack on %s\n",
497 GC_f2s (fwd), GCC_2s (c));
499 /* Check if we need to transmit the ACK. */
500 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
501 if (3 < delta && buffer < delta && GNUNET_NO == force)
503 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
504 LOG (GNUNET_ERROR_TYPE_DEBUG,
505 " last pid recv: %u, last ack sent: %u\n",
506 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
510 /* Ok, ACK might be necessary, what PID to ACK? */
511 ack = prev_fc->last_pid_recv + buffer;
512 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
513 LOG (GNUNET_ERROR_TYPE_DEBUG,
514 " last pid %u, last ack %u, qmax %u, q %u\n",
515 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
516 next_fc->queue_max, next_fc->queue_n);
517 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
519 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
523 /* Check if message is already in queue */
524 if (NULL != prev_fc->ack_msg)
526 if (GC_is_pid_bigger (ack, prev_fc->last_ack_sent))
528 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
529 GCC_cancel (prev_fc->ack_msg);
530 /* GCC_cancel triggers ack_sent(), which clears fc->ack_msg */
534 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
539 prev_fc->last_ack_sent = ack;
541 /* Build ACK message and send on connection */
542 msg.header.size = htons (sizeof (msg));
543 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_ACK);
544 msg.ack = htonl (ack);
547 prev_fc->ack_msg = GCC_send_prebuilt_message (&msg.header, 0, ack, c,
550 GNUNET_assert (NULL != prev_fc->ack_msg);
555 * Callback called when a connection queued message is sent.
557 * Calculates the average time and connection packet tracking.
559 * @param cls Closure (ConnectionQueue Handle).
560 * @param c Connection this message was on.
561 * @param sent Was it really sent? (Could have been canceled)
562 * @param type Type of message sent.
563 * @param pid Packet ID, or 0 if not applicable (create, destroy, etc).
564 * @param fwd Was this a FWD going message?
565 * @param size Size of the message.
566 * @param wait Time spent waiting for core (only the time for THIS message)
568 * @return #GNUNET_YES if connection was destroyed, #GNUNET_NO otherwise.
571 conn_message_sent (void *cls,
572 struct CadetConnection *c, int sent,
573 uint16_t type, uint32_t pid, int fwd, size_t size,
574 struct GNUNET_TIME_Relative wait)
576 struct CadetConnectionPerformance *p;
577 struct CadetFlowControl *fc;
578 struct CadetConnectionQueue *q = cls;
582 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection message_sent\n");
584 fc = fwd ? &c->fwd_fc : &c->bck_fc;
585 LOG (GNUNET_ERROR_TYPE_DEBUG, " %ssent %s %s\n",
586 sent ? "" : "not ", GC_f2s (fwd), GC_m2s (type));
592 LOG (GNUNET_ERROR_TYPE_DEBUG, " calling cont\n");
593 q->cont (q->cont_cls, c, q, type, fwd, size);
597 else if (type == GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED)
599 /* If NULL == q and ENCRYPTED == type, message must have been ch_mngmnt */
608 if (type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN
609 && type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY)
611 LOG (GNUNET_ERROR_TYPE_ERROR, "Message %s sent on NULL connection!\n",
616 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P- %p %u\n", c, c->pending_messages);
617 c->pending_messages--;
618 if (GNUNET_YES == c->destroy && 0 == c->pending_messages)
620 LOG (GNUNET_ERROR_TYPE_DEBUG, "! destroying connection!\n");
624 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
627 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
628 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
629 c->maintenance_q = NULL;
630 /* Don't trigger a keepalive for sent ACKs, only SYN and SYNACKs */
631 if (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE == type || !fwd)
632 schedule_next_keepalive (c, fwd);
635 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
636 if (GNUNET_YES == sent)
638 GNUNET_assert (NULL != q);
639 fc->last_pid_sent = pid; // FIXME
640 GCC_send_ack (c, fwd, GNUNET_NO);
641 connection_reset_timeout (c, fwd);
644 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
645 if (GNUNET_NO == forced)
648 LOG (GNUNET_ERROR_TYPE_DEBUG,
649 "! accounting pid %u\n",
654 LOG (GNUNET_ERROR_TYPE_DEBUG,
655 "! forced, Q_N not accounting pid %u\n",
660 case GNUNET_MESSAGE_TYPE_CADET_KX:
661 if (GNUNET_YES == sent)
662 connection_reset_timeout (c, fwd);
665 case GNUNET_MESSAGE_TYPE_CADET_POLL:
669 case GNUNET_MESSAGE_TYPE_CADET_ACK:
676 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
679 return GNUNET_NO; /* Only endpoints are interested in timing. */
682 usecsperbyte = ((double) wait.rel_value_us) / size;
683 if (p->size == AVG_MSGS)
685 /* Array is full. Substract oldest value, add new one and store. */
686 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
687 p->usecsperbyte[p->idx] = usecsperbyte;
688 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
692 /* Array not yet full. Add current value to avg and store. */
693 p->usecsperbyte[p->idx] = usecsperbyte;
695 p->avg += p->usecsperbyte[p->idx];
699 p->idx = (p->idx + 1) % AVG_MSGS;
705 * Get the previous hop in a connection
707 * @param c Connection.
709 * @return Previous peer in the connection.
711 static struct CadetPeer *
712 get_prev_hop (const struct CadetConnection *c)
716 LOG (GNUNET_ERROR_TYPE_DEBUG, " get prev hop %s [%u/%u]\n",
717 GCC_2s (c), c->own_pos, c->path->length);
718 if (0 == c->own_pos || c->path->length < 2)
719 id = c->path->peers[0];
721 id = c->path->peers[c->own_pos - 1];
723 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
724 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
726 return GCP_get_short (id);
731 * Get the next hop in a connection
733 * @param c Connection.
735 * @return Next peer in the connection.
737 static struct CadetPeer *
738 get_next_hop (const struct CadetConnection *c)
742 LOG (GNUNET_ERROR_TYPE_DEBUG, " get next hop %s [%u/%u]\n",
743 GCC_2s (c), c->own_pos, c->path->length);
744 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
745 id = c->path->peers[c->path->length - 1];
747 id = c->path->peers[c->own_pos + 1];
749 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
750 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
752 return GCP_get_short (id);
757 * Get the hop in a connection.
759 * @param c Connection.
760 * @param fwd Next hop?
762 * @return Next peer in the connection.
764 static struct CadetPeer *
765 get_hop (struct CadetConnection *c, int fwd)
768 return get_next_hop (c);
769 return get_prev_hop (c);
774 * Is traffic coming from this sender 'FWD' traffic?
776 * @param c Connection to check.
777 * @param sender Peer identity of neighbor.
779 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
780 * the traffic is 'FWD'.
781 * #GNUNET_NO for BCK.
782 * #GNUNET_SYSERR for errors.
785 is_fwd (const struct CadetConnection *c,
786 const struct GNUNET_PeerIdentity *sender)
790 id = GNUNET_PEER_search (sender);
791 if (GCP_get_short_id (get_prev_hop (c)) == id)
794 if (GCP_get_short_id (get_next_hop (c)) == id)
798 return GNUNET_SYSERR;
803 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
804 * or a first CONNECTION_ACK directed to us.
806 * @param connection Connection to confirm.
807 * @param fwd Should we send it FWD? (root->dest)
808 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
811 send_connection_ack (struct CadetConnection *connection, int fwd)
813 struct CadetTunnel *t;
816 LOG (GNUNET_ERROR_TYPE_INFO, "===> {%14s ACK} on connection %s\n",
817 GC_f2s (!fwd), GCC_2s (connection));
818 GCP_queue_add (get_hop (connection, fwd), NULL,
819 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK, 0, 0,
820 sizeof (struct GNUNET_CADET_ConnectionACK),
821 connection, fwd, &conn_message_sent, NULL);
822 connection->pending_messages++;
823 if (CADET_TUNNEL_NEW == GCT_get_cstate (t))
824 GCT_change_cstate (t, CADET_TUNNEL_WAITING);
825 if (CADET_CONNECTION_READY != connection->state)
826 connection_change_state (connection, CADET_CONNECTION_SENT);
831 * Send a notification that a connection is broken.
833 * @param c Connection that is broken.
834 * @param id1 Peer that has disconnected.
835 * @param id2 Peer that has disconnected.
836 * @param fwd Direction towards which to send it.
839 send_broken (struct CadetConnection *c,
840 const struct GNUNET_PeerIdentity *id1,
841 const struct GNUNET_PeerIdentity *id2,
844 struct GNUNET_CADET_ConnectionBroken msg;
846 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
847 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
851 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, 0, 0, c, fwd,
852 GNUNET_YES, NULL, NULL));
857 * Send a notification that a connection is broken, when a connection
858 * isn't even known to the local peer.
860 * @param connection_id Connection ID.
861 * @param id1 Peer that has disconnected, probably local peer.
862 * @param id2 Peer that has disconnected can be NULL if unknown.
863 * @param peer Peer to notify (neighbor who sent the connection).
866 send_broken_unknown (const struct GNUNET_CADET_Hash *connection_id,
867 const struct GNUNET_PeerIdentity *id1,
868 const struct GNUNET_PeerIdentity *id2,
869 const struct GNUNET_PeerIdentity *peer_id)
871 struct GNUNET_CADET_ConnectionBroken *msg;
872 struct CadetPeer *neighbor;
874 LOG (GNUNET_ERROR_TYPE_INFO, "===> BROKEN on unknown connection %s\n",
875 GNUNET_h2s (GC_h2hc (connection_id)));
877 msg = GNUNET_new (struct GNUNET_CADET_ConnectionBroken);
878 msg->header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
879 msg->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
880 msg->cid = *connection_id;
885 memset (&msg->peer2, 0, sizeof (msg->peer2));
886 neighbor = GCP_get (peer_id);
887 GCP_queue_add (neighbor, msg, GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN,
888 0, 2, sizeof (struct GNUNET_CADET_ConnectionBroken),
889 NULL, GNUNET_SYSERR, /* connection, fwd */
890 NULL, NULL); /* continuation */
895 * Send keepalive packets for a connection.
897 * @param c Connection to keep alive..
898 * @param fwd Is this a FWD keepalive? (owner -> dest).
901 send_connection_keepalive (struct CadetConnection *c, int fwd)
903 struct GNUNET_MessageHeader msg;
904 struct CadetFlowControl *fc;
906 LOG (GNUNET_ERROR_TYPE_INFO, "keepalive %s for connection %s\n",
907 GC_f2s (fwd), GCC_2s (c));
909 fc = fwd ? &c->fwd_fc : &c->bck_fc;
912 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, traffic in queue\n");
916 GNUNET_STATISTICS_update (stats, "# keepalives sent", 1, GNUNET_NO);
918 GNUNET_assert (NULL != c->t);
919 msg.size = htons (sizeof (msg));
920 msg.type = htons (GNUNET_MESSAGE_TYPE_CADET_KEEPALIVE);
922 GNUNET_assert (NULL ==
923 GCT_send_prebuilt_message (&msg, c->t, c,
924 GNUNET_NO, NULL, NULL));
929 * Send CONNECTION_{CREATE/ACK} packets for a connection.
931 * @param c Connection for which to send the message.
932 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
935 connection_recreate (struct CadetConnection *c, int fwd)
937 LOG (GNUNET_ERROR_TYPE_DEBUG, "sending connection recreate\n");
941 send_connection_ack (c, GNUNET_NO);
946 * Generic connection timer management.
947 * Depending on the role of the peer in the connection will send the
948 * appropriate message (build or keepalive)
950 * @param c Conncetion to maintain.
954 connection_maintain (struct CadetConnection *c, int fwd)
956 if (GNUNET_NO != c->destroy)
958 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, being destroyed\n");
965 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
969 if (CADET_TUNNEL_SEARCHING == GCT_get_cstate (c->t))
971 /* If status is SEARCHING, why is there a connection? Should be WAITING */
973 GCT_debug (c->t, GNUNET_ERROR_TYPE_ERROR);
974 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, tunnel SEARCHING\n");
975 schedule_next_keepalive (c, fwd);
980 case CADET_CONNECTION_NEW:
983 case CADET_CONNECTION_SENT:
984 connection_recreate (c, fwd);
986 case CADET_CONNECTION_READY:
987 send_connection_keepalive (c, fwd);
997 * Keep the connection alive.
999 * @param c Connection to keep alive.
1000 * @param fwd Direction.
1001 * @param shutdown Are we shutting down? (Don't send traffic)
1002 * Non-zero value for true, not necessarily GNUNET_YES.
1005 connection_keepalive (struct CadetConnection *c, int fwd, int shutdown)
1007 LOG (GNUNET_ERROR_TYPE_DEBUG, "%s keepalive for %s\n",
1008 GC_f2s (fwd), GCC_2s (c));
1011 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1013 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1015 if (GNUNET_NO != shutdown)
1018 connection_maintain (c, fwd);
1020 /* Next execution will be scheduled by message_sent or _maintain*/
1025 * Keep the connection alive in the FWD direction.
1027 * @param cls Closure (connection to keepalive).
1028 * @param tc TaskContext.
1031 connection_fwd_keepalive (void *cls,
1032 const struct GNUNET_SCHEDULER_TaskContext *tc)
1034 connection_keepalive ((struct CadetConnection *) cls,
1036 tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN);
1041 * Keep the connection alive in the BCK direction.
1043 * @param cls Closure (connection to keepalive).
1044 * @param tc TaskContext.
1047 connection_bck_keepalive (void *cls,
1048 const struct GNUNET_SCHEDULER_TaskContext *tc)
1050 connection_keepalive ((struct CadetConnection *) cls,
1052 tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN);
1057 * Schedule next keepalive task, taking in consideration
1058 * the connection state and number of retries.
1060 * If the peer is not the origin, do nothing.
1062 * @param c Connection for which to schedule the next keepalive.
1063 * @param fwd Direction for the next keepalive.
1066 schedule_next_keepalive (struct CadetConnection *c, int fwd)
1068 struct GNUNET_TIME_Relative delay;
1069 GNUNET_SCHEDULER_TaskIdentifier *task_id;
1070 GNUNET_SCHEDULER_Task keepalive_task;
1072 if (GNUNET_NO == GCC_is_origin (c, fwd))
1075 /* Calculate delay to use, depending on the state of the connection */
1076 if (CADET_CONNECTION_READY == c->state)
1078 delay = refresh_connection_time;
1082 if (1 > c->create_retry)
1083 c->create_retry = 1;
1084 delay = GNUNET_TIME_relative_multiply (create_connection_time,
1086 if (c->create_retry < 64)
1087 c->create_retry *= 2;
1090 /* Select direction-dependent parameters */
1091 if (GNUNET_YES == fwd)
1093 task_id = &c->fwd_maintenance_task;
1094 keepalive_task = &connection_fwd_keepalive;
1098 task_id = &c->bck_maintenance_task;
1099 keepalive_task = &connection_bck_keepalive;
1102 /* Check that no one scheduled it before us */
1103 if (GNUNET_SCHEDULER_NO_TASK != *task_id)
1105 /* No need for a _break. It can happen for instance when sending a SYNACK
1106 * for a duplicate SYN: the first SYNACK scheduled the task. */
1107 GNUNET_SCHEDULER_cancel (*task_id);
1110 /* Schedule the task */
1111 *task_id = GNUNET_SCHEDULER_add_delayed (delay, keepalive_task, c);
1112 LOG (GNUNET_ERROR_TYPE_DEBUG, "next keepalive in %s\n",
1113 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1118 * @brief Re-initiate traffic on this connection if necessary.
1120 * Check if there is traffic queued towards this peer
1121 * and the core transmit handle is NULL (traffic was stalled).
1122 * If so, call core tmt rdy.
1124 * @param c Connection on which initiate traffic.
1125 * @param fwd Is this about fwd traffic?
1128 connection_unlock_queue (struct CadetConnection *c, int fwd)
1130 struct CadetPeer *peer;
1132 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection_unlock_queue %s on %s\n",
1133 GC_f2s (fwd), GCC_2s (c));
1135 if (GCC_is_terminal (c, fwd))
1137 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal, can unlock!\n");
1141 peer = get_hop (c, fwd);
1142 GCP_queue_unlock (peer, c);
1147 * Cancel all transmissions that belong to a certain connection.
1149 * If the connection is scheduled for destruction and no more messages are left,
1150 * the connection will be destroyed by the continuation call.
1152 * @param c Connection which to cancel. Might be destroyed during this call.
1153 * @param fwd Cancel fwd traffic?
1156 connection_cancel_queues (struct CadetConnection *c, int fwd)
1158 struct CadetFlowControl *fc;
1159 struct CadetPeer *peer;
1161 LOG (GNUNET_ERROR_TYPE_DEBUG,
1162 " *** Cancel %s queues for connection %s\n",
1163 GC_f2s (fwd), GCC_2s (c));
1170 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1171 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
1173 GNUNET_SCHEDULER_cancel (fc->poll_task);
1174 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1175 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Cancel POLL in ccq for fc %p\n", fc);
1177 peer = get_hop (c, fwd);
1178 GCP_queue_cancel (peer, c);
1183 * Function called if a connection has been stalled for a while,
1184 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1186 * @param cls Closure (poll ctx).
1187 * @param tc TaskContext.
1190 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
1194 * Callback called when a queued POLL message is sent.
1196 * @param cls Closure (FC).
1197 * @param c Connection this message was on.
1198 * @param q Queue handler this call invalidates.
1199 * @param type Type of message sent.
1200 * @param fwd Was this a FWD going message?
1201 * @param size Size of the message.
1204 poll_sent (void *cls,
1205 struct CadetConnection *c,
1206 struct CadetConnectionQueue *q,
1207 uint16_t type, int fwd, size_t size)
1209 struct CadetFlowControl *fc = cls;
1211 if (2 == c->destroy)
1213 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL canceled on shutdown\n");
1216 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL sent for , scheduling new one!\n");
1217 fc->poll_msg = NULL;
1218 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1219 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1220 &connection_poll, fc);
1221 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1226 * Function called if a connection has been stalled for a while,
1227 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1229 * @param cls Closure (poll ctx).
1230 * @param tc TaskContext.
1233 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1235 struct CadetFlowControl *fc = cls;
1236 struct GNUNET_CADET_Poll msg;
1237 struct CadetConnection *c;
1239 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
1240 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1246 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** Polling connection %s %s\n",
1247 GCC_2s (c), fc == &c->fwd_fc ? "FWD" : "BCK");
1249 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_POLL);
1250 msg.header.size = htons (sizeof (msg));
1251 msg.pid = htonl (fc->last_pid_sent);
1252 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** last pid sent: %u!\n", fc->last_pid_sent);
1254 GCC_send_prebuilt_message (&msg.header, 0, fc->last_pid_sent, c,
1255 fc == &c->fwd_fc, GNUNET_YES, &poll_sent, fc);
1256 GNUNET_assert (NULL != fc->poll_msg);
1261 * Timeout function due to lack of keepalive/traffic from the owner.
1262 * Destroys connection if called.
1264 * @param cls Closure (connection to destroy).
1265 * @param tc TaskContext.
1268 connection_fwd_timeout (void *cls,
1269 const struct GNUNET_SCHEDULER_TaskContext *tc)
1271 struct CadetConnection *c = cls;
1273 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1274 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1277 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s FWD timed out. Destroying.\n",
1279 if (GCC_is_origin (c, GNUNET_YES)) /* If local, leave. */
1285 /* If dest, salvage queued traffic. */
1286 if (GCC_is_origin (c, GNUNET_NO) && 0 < c->bck_fc.queue_n)
1288 struct GNUNET_MessageHeader *out_msg;
1289 struct CadetPeer *neighbor;
1290 struct CadetTunnel *t;
1294 c->destroy = GNUNET_YES;
1295 destroyed = GNUNET_NO;
1296 neighbor = get_hop (c, GNUNET_NO);
1298 /* GCP_connection_pop could destroy the connection! */
1299 while (NULL != (out_msg = GCP_connection_pop (neighbor, c, &destroyed)))
1301 GCT_resend_message (out_msg, t);
1303 /* All pending messages should have been popped,
1304 * and the connection destroyed by the continuation.
1306 if (GNUNET_YES != destroyed)
1309 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1320 * Timeout function due to lack of keepalive/traffic from the destination.
1321 * Destroys connection if called.
1323 * FIXME refactor and merge with connection_fwd_timeout.
1325 * @param cls Closure (connection to destroy).
1326 * @param tc TaskContext
1329 connection_bck_timeout (void *cls,
1330 const struct GNUNET_SCHEDULER_TaskContext *tc)
1332 struct CadetConnection *c = cls;
1334 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1335 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1338 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s BCK timed out. Destroying.\n",
1341 if (GCC_is_origin (c, GNUNET_NO)) /* If local, leave. */
1347 /* If dest, salvage queued traffic. */
1348 if (GCC_is_origin (c, GNUNET_YES) && 0 < c->fwd_fc.queue_n)
1350 struct GNUNET_MessageHeader *out_msg;
1351 struct CadetPeer *neighbor;
1352 struct CadetTunnel *t;
1356 c->destroy = GNUNET_YES;
1357 destroyed = GNUNET_NO;
1358 neighbor = get_hop (c, GNUNET_YES);
1360 /* GCP_connection_pop could destroy the connection! */
1361 while (NULL != (out_msg = GCP_connection_pop (neighbor, c, &destroyed)))
1363 GCT_resend_message (out_msg, t);
1365 /* All pending messages should have been popped,
1366 * and the connection destroyed by the continuation.
1368 if (GNUNET_YES != destroyed)
1371 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1382 * Resets the connection timeout task, some other message has done the
1384 * - For the first peer on the direction this means to send
1385 * a keepalive or a path confirmation message (either create or ACK).
1386 * - For all other peers, this means to destroy the connection,
1387 * due to lack of activity.
1388 * Starts the timeout if no timeout was running (connection just created).
1390 * @param c Connection whose timeout to reset.
1391 * @param fwd Is this forward?
1393 * TODO use heap to improve efficiency of scheduler.
1396 connection_reset_timeout (struct CadetConnection *c, int fwd)
1398 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1400 if (GCC_is_origin (c, fwd)) /* Startpoint */
1402 schedule_next_keepalive (c, fwd);
1404 else /* Relay, endpoint. */
1406 struct GNUNET_TIME_Relative delay;
1407 GNUNET_SCHEDULER_TaskIdentifier *ti;
1408 GNUNET_SCHEDULER_Task f;
1410 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1412 if (GNUNET_SCHEDULER_NO_TASK != *ti)
1413 GNUNET_SCHEDULER_cancel (*ti);
1414 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1415 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1416 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1422 * Add the connection to the list of both neighbors.
1424 * @param c Connection.
1426 * @return #GNUNET_OK if everything went fine
1427 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1430 register_neighbors (struct CadetConnection *c)
1432 struct CadetPeer *next_peer;
1433 struct CadetPeer *prev_peer;
1435 next_peer = get_next_hop (c);
1436 prev_peer = get_prev_hop (c);
1438 LOG (GNUNET_ERROR_TYPE_DEBUG, "register neighbors for connection %s\n",
1440 path_debug (c->path);
1441 LOG (GNUNET_ERROR_TYPE_DEBUG, "own pos %u\n", c->own_pos);
1442 LOG (GNUNET_ERROR_TYPE_DEBUG, "putting connection %s to next peer %p\n",
1443 GCC_2s (c), next_peer);
1444 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n", next_peer, GCP_2s (next_peer));
1445 LOG (GNUNET_ERROR_TYPE_DEBUG, "putting connection %s to prev peer %p\n",
1446 GCC_2s (c), prev_peer);
1447 LOG (GNUNET_ERROR_TYPE_DEBUG, "prev peer %p %s\n", prev_peer, GCP_2s (prev_peer));
1449 if (GNUNET_NO == GCP_is_neighbor (next_peer)
1450 || GNUNET_NO == GCP_is_neighbor (prev_peer))
1452 if (GCC_is_origin (c, GNUNET_YES))
1453 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1454 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1456 LOG (GNUNET_ERROR_TYPE_DEBUG, " register neighbors failed\n");
1457 LOG (GNUNET_ERROR_TYPE_DEBUG, " prev: %s, neighbor?: %d\n",
1458 GCP_2s (prev_peer), GCP_is_neighbor (prev_peer));
1459 LOG (GNUNET_ERROR_TYPE_DEBUG, " next: %s, neighbor?: %d\n",
1460 GCP_2s (next_peer), GCP_is_neighbor (next_peer));
1461 return GNUNET_SYSERR;
1464 GCP_add_connection (next_peer, c);
1465 GCP_add_connection (prev_peer, c);
1472 * Remove the connection from the list of both neighbors.
1474 * @param c Connection.
1477 unregister_neighbors (struct CadetConnection *c)
1479 struct CadetPeer *peer;
1481 peer = get_next_hop (c);
1482 if (GNUNET_OK != GCP_remove_connection (peer, c))
1484 GNUNET_assert (CADET_CONNECTION_NEW == c->state
1485 || CADET_CONNECTION_DESTROYED <= c->state);
1486 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate: %u\n", c->state);
1487 if (NULL != c->t) GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1490 peer = get_prev_hop (c);
1491 if (GNUNET_OK != GCP_remove_connection (peer, c))
1493 GNUNET_assert (CADET_CONNECTION_NEW == c->state
1494 || CADET_CONNECTION_DESTROYED <= c->state);
1495 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate: %u\n", c->state);
1496 if (NULL != c->t) GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1502 * Bind the connection to the peer and the tunnel to that peer.
1504 * If the peer has no tunnel, create one. Update tunnel and connection
1505 * data structres to reflect new status.
1507 * @param c Connection.
1511 add_to_peer (struct CadetConnection *c, struct CadetPeer *peer)
1513 GCP_add_tunnel (peer);
1514 c->t = GCP_get_tunnel (peer);
1515 GCT_add_connection (c->t, c);
1520 * Log receipt of message on stderr (INFO level).
1522 * @param message Message received.
1523 * @param peer Peer who sent the message.
1524 * @param hash Connection ID.
1527 log_message (const struct GNUNET_MessageHeader *message,
1528 const struct GNUNET_PeerIdentity *peer,
1529 const struct GNUNET_CADET_Hash *hash)
1531 LOG (GNUNET_ERROR_TYPE_INFO, "<-- %s on connection %s from %s\n",
1532 GC_m2s (ntohs (message->type)), GNUNET_h2s (GC_h2hc (hash)),
1536 /******************************************************************************/
1537 /******************************** API ***********************************/
1538 /******************************************************************************/
1541 * Core handler for connection creation.
1543 * @param cls Closure (unused).
1544 * @param peer Sender (neighbor).
1545 * @param message Message.
1547 * @return GNUNET_OK to keep the connection open,
1548 * GNUNET_SYSERR to close it (signal serious error)
1551 GCC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
1552 const struct GNUNET_MessageHeader *message)
1554 struct GNUNET_CADET_ConnectionCreate *msg;
1555 struct GNUNET_PeerIdentity *id;
1556 struct GNUNET_CADET_Hash *cid;
1557 struct CadetPeerPath *path;
1558 struct CadetPeer *dest_peer;
1559 struct CadetPeer *orig_peer;
1560 struct CadetConnection *c;
1561 unsigned int own_pos;
1565 size = ntohs (message->size);
1566 if (size < sizeof (struct GNUNET_CADET_ConnectionCreate))
1568 GNUNET_break_op (0);
1572 /* Calculate hops */
1573 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
1574 if (size % sizeof (struct GNUNET_PeerIdentity))
1576 GNUNET_break_op (0);
1579 size /= sizeof (struct GNUNET_PeerIdentity);
1582 GNUNET_break_op (0);
1585 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1587 /* Get parameters */
1588 msg = (struct GNUNET_CADET_ConnectionCreate *) message;
1590 log_message (message, peer, cid);
1591 id = (struct GNUNET_PeerIdentity *) &msg[1];
1592 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
1594 /* Create connection */
1595 c = connection_get (cid);
1598 path = path_build_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
1599 size, myid, &own_pos);
1605 GNUNET_break_op (0);
1606 path_destroy (path);
1609 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1610 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1611 c = GCC_new (cid, NULL, path_duplicate (path), own_pos);
1614 if (path->length - 1 == own_pos)
1616 /* If we are destination, why did the creation fail? */
1618 path_destroy (path);
1621 send_broken_unknown (cid, &my_full_id,
1622 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
1624 path_destroy (path);
1627 GCP_add_path_to_all (path, GNUNET_NO);
1628 connection_reset_timeout (c, GNUNET_YES);
1632 path = path_duplicate (c->path);
1634 if (CADET_CONNECTION_NEW == c->state)
1635 connection_change_state (c, CADET_CONNECTION_SENT);
1637 /* Remember peers */
1638 dest_peer = GCP_get (&id[size - 1]);
1639 orig_peer = GCP_get (&id[0]);
1641 /* Is it a connection to us? */
1642 if (c->own_pos == path->length - 1)
1644 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1645 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
1647 add_to_peer (c, orig_peer);
1648 if (CADET_TUNNEL_NEW == GCT_get_cstate (c->t))
1649 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
1651 send_connection_ack (c, GNUNET_NO);
1652 if (CADET_CONNECTION_SENT == c->state)
1653 connection_change_state (c, CADET_CONNECTION_ACK);
1657 /* It's for somebody else! Retransmit. */
1658 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
1659 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1660 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
1661 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c,
1662 GNUNET_YES, GNUNET_YES,
1665 path_destroy (path);
1671 * Core handler for path confirmations.
1673 * @param cls closure
1674 * @param message message
1675 * @param peer peer identity this notification is about
1677 * @return GNUNET_OK to keep the connection open,
1678 * GNUNET_SYSERR to close it (signal serious error)
1681 GCC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
1682 const struct GNUNET_MessageHeader *message)
1684 struct GNUNET_CADET_ConnectionACK *msg;
1685 struct CadetConnection *c;
1686 struct CadetPeerPath *p;
1687 struct CadetPeer *pi;
1688 enum CadetConnectionState oldstate;
1691 msg = (struct GNUNET_CADET_ConnectionACK *) message;
1692 log_message (message, peer, &msg->cid);
1693 c = connection_get (&msg->cid);
1696 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1698 LOG (GNUNET_ERROR_TYPE_DEBUG, " don't know the connection!\n");
1699 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
1703 if (GNUNET_NO != c->destroy)
1705 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection being destroyed\n");
1709 oldstate = c->state;
1710 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
1711 pi = GCP_get (peer);
1712 if (get_next_hop (c) == pi)
1714 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
1716 if (CADET_CONNECTION_SENT == oldstate)
1717 connection_change_state (c, CADET_CONNECTION_ACK);
1719 else if (get_prev_hop (c) == pi)
1721 LOG (GNUNET_ERROR_TYPE_DEBUG, " FINAL ACK\n");
1723 connection_change_state (c, CADET_CONNECTION_READY);
1727 GNUNET_break_op (0);
1731 connection_reset_timeout (c, fwd);
1733 /* Add path to peers? */
1737 GCP_add_path_to_all (p, GNUNET_YES);
1744 /* Message for us as creator? */
1745 if (GCC_is_origin (c, GNUNET_YES))
1747 if (GNUNET_NO != fwd)
1749 GNUNET_break_op (0);
1752 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
1754 /* If just created, cancel the short timeout and start a long one */
1755 if (CADET_CONNECTION_SENT == oldstate)
1756 connection_reset_timeout (c, GNUNET_YES);
1758 /* Change connection state */
1759 connection_change_state (c, CADET_CONNECTION_READY);
1760 send_connection_ack (c, GNUNET_YES);
1762 /* Change tunnel state, trigger KX */
1763 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
1764 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
1769 /* Message for us as destination? */
1770 if (GCC_is_terminal (c, GNUNET_YES))
1772 if (GNUNET_YES != fwd)
1774 GNUNET_break_op (0);
1777 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
1779 /* If just created, cancel the short timeout and start a long one */
1780 if (CADET_CONNECTION_ACK == oldstate)
1781 connection_reset_timeout (c, GNUNET_NO);
1783 /* Change tunnel state */
1784 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
1785 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
1790 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1791 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
1792 GNUNET_YES, NULL, NULL));
1798 * Core handler for notifications of broken connections.
1800 * @param cls Closure (unused).
1801 * @param id Peer identity of sending neighbor.
1802 * @param message Message.
1804 * @return GNUNET_OK to keep the connection open,
1805 * GNUNET_SYSERR to close it (signal serious error)
1808 GCC_handle_broken (void* cls,
1809 const struct GNUNET_PeerIdentity* id,
1810 const struct GNUNET_MessageHeader* message)
1812 struct GNUNET_CADET_ConnectionBroken *msg;
1813 struct CadetConnection *c;
1814 struct CadetTunnel *t;
1818 msg = (struct GNUNET_CADET_ConnectionBroken *) message;
1819 log_message (message, id, &msg->cid);
1820 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1821 GNUNET_i2s (&msg->peer1));
1822 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1823 GNUNET_i2s (&msg->peer2));
1824 c = connection_get (&msg->cid);
1827 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
1832 fwd = is_fwd (c, id);
1833 c->destroy = GNUNET_YES;
1834 if (GCC_is_terminal (c, fwd))
1836 struct GNUNET_MessageHeader *out_msg;
1837 struct CadetPeer *neighbor;
1838 struct CadetPeer *endpoint;
1842 /* A terminal connection should not have 't' set to NULL. */
1844 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1847 neighbor = get_hop (c, !fwd);
1848 endpoint = GCP_get_short (c->path->peers[c->path->length - 1]);
1849 path_invalidate (c->path);
1850 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
1852 c->state = CADET_CONNECTION_BROKEN;
1853 GCT_remove_connection (t, c);
1856 pending = c->pending_messages;
1861 destroyed = GNUNET_NO;
1863 /* GCP_connection_pop could destroy the connection! */
1864 while (NULL != (out_msg = GCP_connection_pop (neighbor, c, &destroyed)))
1866 GCT_resend_message (out_msg, t);
1869 /* All pending messages should have been popped,
1870 * and the connection destroyed by the continuation,
1871 * except if the queue was empty. */
1872 if (GNUNET_YES != destroyed)
1875 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1876 GCT_debug (t, GNUNET_ERROR_TYPE_ERROR);
1887 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
1888 GNUNET_YES, NULL, NULL));
1889 connection_cancel_queues (c, !fwd);
1897 * Core handler for tunnel destruction
1899 * @param cls Closure (unused).
1900 * @param peer Peer identity of sending neighbor.
1901 * @param message Message.
1903 * @return GNUNET_OK to keep the connection open,
1904 * GNUNET_SYSERR to close it (signal serious error)
1907 GCC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
1908 const struct GNUNET_MessageHeader *message)
1910 struct GNUNET_CADET_ConnectionDestroy *msg;
1911 struct CadetConnection *c;
1914 msg = (struct GNUNET_CADET_ConnectionDestroy *) message;
1915 log_message (message, peer, &msg->cid);
1916 c = connection_get (&msg->cid);
1919 /* Probably already got the message from another path,
1920 * destroyed the tunnel and retransmitted to children.
1923 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1925 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection unknown: already destroyed?\n");
1928 fwd = is_fwd (c, peer);
1929 if (GNUNET_SYSERR == fwd)
1931 GNUNET_break_op (0); /* FIXME */
1934 if (GNUNET_NO == GCC_is_terminal (c, fwd))
1935 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
1936 GNUNET_YES, NULL, NULL));
1937 else if (0 == c->pending_messages)
1939 LOG (GNUNET_ERROR_TYPE_DEBUG, " directly destroying connection!\n");
1943 c->destroy = GNUNET_YES;
1944 c->state = CADET_CONNECTION_DESTROYED;
1947 GCT_remove_connection (c->t, c);
1955 * Generic handler for cadet network encrypted traffic.
1957 * @param peer Peer identity this notification is about.
1958 * @param msg Encrypted message.
1960 * @return GNUNET_OK to keep the connection open,
1961 * GNUNET_SYSERR to close it (signal serious error)
1964 handle_cadet_encrypted (const struct GNUNET_PeerIdentity *peer,
1965 const struct GNUNET_CADET_Encrypted *msg)
1967 struct CadetConnection *c;
1968 struct CadetPeer *neighbor;
1969 struct CadetFlowControl *fc;
1970 GNUNET_PEER_Id peer_id;
1976 log_message (&msg->header, peer, &msg->cid);
1979 size = ntohs (msg->header.size);
1981 sizeof (struct GNUNET_CADET_Encrypted) +
1982 sizeof (struct GNUNET_MessageHeader))
1984 GNUNET_break_op (0);
1988 /* Check connection */
1989 c = connection_get (&msg->cid);
1992 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1993 LOG (GNUNET_ERROR_TYPE_DEBUG, "enc on unknown connection %s\n",
1994 GNUNET_h2s (GC_h2hc (&msg->cid)));
1995 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
1999 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s\n", GCC_2s (c));
2001 /* Check if origin is as expected */
2002 neighbor = get_prev_hop (c);
2003 peer_id = GNUNET_PEER_search (peer);
2004 if (peer_id == GCP_get_short_id (neighbor))
2010 neighbor = get_next_hop (c);
2011 if (peer_id == GCP_get_short_id (neighbor))
2017 /* Unexpected peer sending traffic on a connection. */
2018 GNUNET_break_op (0);
2024 fc = fwd ? &c->bck_fc : &c->fwd_fc;
2025 pid = ntohl (msg->pid);
2026 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u+)\n",
2027 pid, fc->last_pid_recv + 1);
2028 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
2030 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
2031 GNUNET_break_op (0);
2032 LOG (GNUNET_ERROR_TYPE_WARNING,
2033 "Received PID %u, (prev %u), ACK %u\n",
2034 pid, fc->last_pid_recv, fc->last_ack_sent);
2037 if (GNUNET_NO == GC_is_pid_bigger (pid, fc->last_pid_recv))
2039 GNUNET_STATISTICS_update (stats, "# duplicate PID", 1, GNUNET_NO);
2040 LOG (GNUNET_ERROR_TYPE_DEBUG,
2041 " PID %u not expected (%u+), dropping!\n",
2042 pid, fc->last_pid_recv + 1);
2045 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2046 connection_change_state (c, CADET_CONNECTION_READY);
2047 connection_reset_timeout (c, fwd);
2048 fc->last_pid_recv = pid;
2050 /* Is this message for us? */
2051 if (GCC_is_terminal (c, fwd))
2053 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2054 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
2058 GNUNET_break (GNUNET_NO != c->destroy);
2061 fc->last_pid_recv = pid;
2062 GCT_handle_encrypted (c->t, msg);
2063 GCC_send_ack (c, fwd, GNUNET_NO);
2067 /* Message not for us: forward to next hop */
2068 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2069 ttl = ntohl (msg->ttl);
2070 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
2073 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
2074 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
2075 GCC_send_ack (c, fwd, GNUNET_NO);
2079 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2080 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2081 GNUNET_NO, NULL, NULL));
2087 * Generic handler for cadet network encrypted traffic.
2089 * @param peer Peer identity this notification is about.
2090 * @param msg Encrypted message.
2092 * @return GNUNET_OK to keep the connection open,
2093 * GNUNET_SYSERR to close it (signal serious error)
2096 handle_cadet_kx (const struct GNUNET_PeerIdentity *peer,
2097 const struct GNUNET_CADET_KX *msg)
2099 struct CadetConnection *c;
2100 struct CadetPeer *neighbor;
2101 GNUNET_PEER_Id peer_id;
2105 log_message (&msg->header, peer, &msg->cid);
2108 size = ntohs (msg->header.size);
2110 sizeof (struct GNUNET_CADET_KX) +
2111 sizeof (struct GNUNET_MessageHeader))
2113 GNUNET_break_op (0);
2117 /* Check connection */
2118 c = connection_get (&msg->cid);
2121 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
2122 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx on unknown connection %s\n",
2123 GNUNET_h2s (GC_h2hc (&msg->cid)));
2124 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2127 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n", GCC_2s (c));
2129 /* Check if origin is as expected */
2130 neighbor = get_prev_hop (c);
2131 peer_id = GNUNET_PEER_search (peer);
2132 if (peer_id == GCP_get_short_id (neighbor))
2138 neighbor = get_next_hop (c);
2139 if (peer_id == GCP_get_short_id (neighbor))
2145 /* Unexpected peer sending traffic on a connection. */
2146 GNUNET_break_op (0);
2151 /* Count as connection confirmation. */
2152 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2154 connection_change_state (c, CADET_CONNECTION_READY);
2157 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2158 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2161 connection_reset_timeout (c, fwd);
2163 /* Is this message for us? */
2164 if (GCC_is_terminal (c, fwd))
2166 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2167 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
2173 GCT_handle_kx (c->t, &msg[1].header);
2177 /* Message not for us: forward to next hop */
2178 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2179 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2180 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2181 GNUNET_NO, NULL, NULL));
2188 * Core handler for encrypted cadet network traffic (channel mgmt, data).
2190 * @param cls Closure (unused).
2191 * @param message Message received.
2192 * @param peer Peer who sent the message.
2194 * @return GNUNET_OK to keep the connection open,
2195 * GNUNET_SYSERR to close it (signal serious error)
2198 GCC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
2199 const struct GNUNET_MessageHeader *message)
2201 return handle_cadet_encrypted (peer,
2202 (struct GNUNET_CADET_Encrypted *)message);
2207 * Core handler for key exchange traffic (ephemeral key, ping, pong).
2209 * @param cls Closure (unused).
2210 * @param message Message received.
2211 * @param peer Peer who sent the message.
2213 * @return GNUNET_OK to keep the connection open,
2214 * GNUNET_SYSERR to close it (signal serious error)
2217 GCC_handle_kx (void *cls, const struct GNUNET_PeerIdentity *peer,
2218 const struct GNUNET_MessageHeader *message)
2220 return handle_cadet_kx (peer,
2221 (struct GNUNET_CADET_KX *) message);
2226 * Core handler for cadet network traffic point-to-point acks.
2228 * @param cls closure
2229 * @param message message
2230 * @param peer peer identity this notification is about
2232 * @return GNUNET_OK to keep the connection open,
2233 * GNUNET_SYSERR to close it (signal serious error)
2236 GCC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
2237 const struct GNUNET_MessageHeader *message)
2239 struct GNUNET_CADET_ACK *msg;
2240 struct CadetConnection *c;
2241 struct CadetFlowControl *fc;
2246 msg = (struct GNUNET_CADET_ACK *) message;
2247 log_message (message, peer, &msg->cid);
2248 c = connection_get (&msg->cid);
2251 GNUNET_STATISTICS_update (stats, "# ack on unknown connection", 1,
2253 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2257 /* Is this a forward or backward ACK? */
2258 id = GNUNET_PEER_search (peer);
2259 if (GCP_get_short_id (get_next_hop (c)) == id)
2261 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
2265 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2267 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
2273 GNUNET_break_op (0);
2277 ack = ntohl (msg->ack);
2278 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u (was %u)\n",
2279 ack, fc->last_ack_recv);
2280 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2281 fc->last_ack_recv = ack;
2283 /* Cancel polling if the ACK is big enough. */
2284 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task &&
2285 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2287 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2288 GNUNET_SCHEDULER_cancel (fc->poll_task);
2289 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2290 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2293 connection_unlock_queue (c, fwd);
2300 * Core handler for cadet network traffic point-to-point ack polls.
2302 * @param cls closure
2303 * @param message message
2304 * @param peer peer identity this notification is about
2306 * @return GNUNET_OK to keep the connection open,
2307 * GNUNET_SYSERR to close it (signal serious error)
2310 GCC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
2311 const struct GNUNET_MessageHeader *message)
2313 struct GNUNET_CADET_Poll *msg;
2314 struct CadetConnection *c;
2315 struct CadetFlowControl *fc;
2320 msg = (struct GNUNET_CADET_Poll *) message;
2321 log_message (message, peer, &msg->cid);
2322 c = connection_get (&msg->cid);
2325 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2327 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL message on unknown connection %s!\n",
2328 GNUNET_h2s (GC_h2hc (&msg->cid)));
2329 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2333 /* Is this a forward or backward ACK?
2334 * Note: a poll should never be needed in a loopback case,
2335 * since there is no possiblility of packet loss there, so
2336 * this way of discerining FWD/BCK should not be a problem.
2338 id = GNUNET_PEER_search (peer);
2339 if (GCP_get_short_id (get_next_hop (c)) == id)
2341 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2344 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2346 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2351 GNUNET_break_op (0);
2355 pid = ntohl (msg->pid);
2356 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2357 fc->last_pid_recv = pid;
2358 fwd = fc == &c->bck_fc;
2359 GCC_send_ack (c, fwd, GNUNET_YES);
2366 * Send an ACK on the appropriate connection/channel, depending on
2367 * the direction and the position of the peer.
2369 * @param c Which connection to send the hop-by-hop ACK.
2370 * @param fwd Is this a fwd ACK? (will go dest->root).
2371 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2374 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
2376 unsigned int buffer;
2378 LOG (GNUNET_ERROR_TYPE_DEBUG,
2379 "GMC send %s ACK on %s\n",
2380 GC_f2s (fwd), GCC_2s (c));
2388 if (GNUNET_NO != c->destroy)
2390 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2394 /* Get available buffer space */
2395 if (GCC_is_terminal (c, fwd))
2397 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2398 buffer = GCT_get_channels_buffer (c->t);
2402 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2403 buffer = GCC_get_buffer (c, fwd);
2405 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2406 if (0 == buffer && GNUNET_NO == force)
2409 /* Send available buffer space */
2410 if (GCC_is_origin (c, fwd))
2412 GNUNET_assert (NULL != c->t);
2413 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2414 GCT_unchoke_channels (c->t);
2418 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2419 send_ack (c, buffer, fwd, force);
2425 * Initialize the connections subsystem
2427 * @param c Configuration handle.
2430 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2432 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2434 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2437 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2438 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2439 GNUNET_SCHEDULER_shutdown ();
2444 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2447 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2448 "CADET", "MAX_CONNECTIONS", "MISSING");
2449 GNUNET_SCHEDULER_shutdown ();
2454 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2455 &refresh_connection_time))
2457 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2458 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2459 GNUNET_SCHEDULER_shutdown ();
2462 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2463 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2468 * Destroy each connection on shutdown.
2470 * @param cls Closure (unused).
2471 * @param key Current key code (CID, unused).
2472 * @param value Value in the hash map (connection)
2474 * @return #GNUNET_YES, because we should continue to iterate,
2477 shutdown_iterator (void *cls,
2478 const struct GNUNET_HashCode *key,
2481 struct CadetConnection *c = value;
2489 * Shut down the connections subsystem.
2494 GNUNET_CONTAINER_multihashmap_iterate (connections, &shutdown_iterator, NULL);
2495 GNUNET_CONTAINER_multihashmap_destroy (connections);
2500 struct CadetConnection *
2501 GCC_new (const struct GNUNET_CADET_Hash *cid,
2502 struct CadetTunnel *t,
2503 struct CadetPeerPath *p,
2504 unsigned int own_pos)
2506 struct CadetConnection *c;
2508 c = GNUNET_new (struct CadetConnection);
2510 GNUNET_assert (GNUNET_OK ==
2511 GNUNET_CONTAINER_multihashmap_put (connections,
2513 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2514 fc_init (&c->fwd_fc);
2515 fc_init (&c->bck_fc);
2520 GNUNET_assert (own_pos <= p->length - 1);
2521 c->own_pos = own_pos;
2525 if (GNUNET_OK != register_neighbors (c))
2529 path_invalidate (c->path);
2542 GCC_destroy (struct CadetConnection *c)
2550 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
2551 return; /* -> message_sent -> GCC_destroy. Don't loop. */
2554 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying connection %s\n", GCC_2s (c));
2555 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc's f: %p, b: %p\n",
2556 &c->fwd_fc, &c->bck_fc);
2557 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2558 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2560 /* Cancel all traffic */
2561 if (NULL != c->path)
2563 connection_cancel_queues (c, GNUNET_YES);
2564 connection_cancel_queues (c, GNUNET_NO);
2565 unregister_neighbors (c);
2568 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2569 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2571 /* Cancel maintainance task (keepalive/timeout) */
2572 if (NULL != c->fwd_fc.poll_msg)
2574 GCC_cancel (c->fwd_fc.poll_msg);
2575 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg FWD canceled\n");
2577 if (NULL != c->bck_fc.poll_msg)
2579 GCC_cancel (c->bck_fc.poll_msg);
2580 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg BCK canceled\n");
2583 /* Delete from tunnel */
2585 GCT_remove_connection (c->t, c);
2587 if (GNUNET_NO == GCC_is_origin (c, GNUNET_YES) && NULL != c->path)
2588 path_destroy (c->path);
2589 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_maintenance_task)
2590 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2591 if (GNUNET_SCHEDULER_NO_TASK != c->bck_maintenance_task)
2592 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2593 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_fc.poll_task)
2595 GNUNET_SCHEDULER_cancel (c->fwd_fc.poll_task);
2596 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL FWD canceled\n");
2598 if (GNUNET_SCHEDULER_NO_TASK != c->bck_fc.poll_task)
2600 GNUNET_SCHEDULER_cancel (c->bck_fc.poll_task);
2601 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL BCK canceled\n");
2604 GNUNET_break (GNUNET_YES ==
2605 GNUNET_CONTAINER_multihashmap_remove (connections,
2608 GNUNET_STATISTICS_update (stats, "# connections", -1, GNUNET_NO);
2613 * Get the connection ID.
2615 * @param c Connection to get the ID from.
2617 * @return ID of the connection.
2619 const struct GNUNET_CADET_Hash *
2620 GCC_get_id (const struct CadetConnection *c)
2627 * Get the connection ID.
2629 * @param c Connection to get the ID from.
2631 * @return ID of the connection.
2633 const struct GNUNET_HashCode *
2634 GCC_get_h (const struct CadetConnection *c)
2636 return GC_h2hc (&c->id);
2641 * Get the connection path.
2643 * @param c Connection to get the path from.
2645 * @return path used by the connection.
2647 const struct CadetPeerPath *
2648 GCC_get_path (const struct CadetConnection *c)
2650 if (GNUNET_NO == c->destroy)
2657 * Get the connection state.
2659 * @param c Connection to get the state from.
2661 * @return state of the connection.
2663 enum CadetConnectionState
2664 GCC_get_state (const struct CadetConnection *c)
2670 * Get the connection tunnel.
2672 * @param c Connection to get the tunnel from.
2674 * @return tunnel of the connection.
2676 struct CadetTunnel *
2677 GCC_get_tunnel (const struct CadetConnection *c)
2684 * Get free buffer space in a connection.
2686 * @param c Connection.
2687 * @param fwd Is query about FWD traffic?
2689 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2692 GCC_get_buffer (struct CadetConnection *c, int fwd)
2694 struct CadetFlowControl *fc;
2696 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2698 return (fc->queue_max - fc->queue_n);
2702 * Get how many messages have we allowed to send to us from a direction.
2704 * @param c Connection.
2705 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2707 * @return last_ack_sent - last_pid_recv
2710 GCC_get_allowed (struct CadetConnection *c, int fwd)
2712 struct CadetFlowControl *fc;
2714 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2715 if (GC_is_pid_bigger (fc->last_pid_recv, fc->last_ack_sent))
2719 return (fc->last_ack_sent - fc->last_pid_recv);
2723 * Get messages queued in a connection.
2725 * @param c Connection.
2726 * @param fwd Is query about FWD traffic?
2728 * @return Number of messages queued.
2731 GCC_get_qn (struct CadetConnection *c, int fwd)
2733 struct CadetFlowControl *fc;
2735 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2742 * Get next PID to use.
2744 * @param c Connection.
2745 * @param fwd Is query about FWD traffic?
2747 * @return Last PID used + 1.
2750 GCC_get_pid (struct CadetConnection *c, int fwd)
2752 struct CadetFlowControl *fc;
2754 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2756 return fc->last_pid_sent + 1;
2761 * Allow the connection to advertise a buffer of the given size.
2763 * The connection will send an @c fwd ACK message (so: in direction !fwd)
2764 * allowing up to last_pid_recv + buffer.
2766 * @param c Connection.
2767 * @param buffer How many more messages the connection can accept.
2768 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
2771 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
2773 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
2774 GCC_2s (c), buffer, GC_f2s (fwd));
2775 send_ack (c, buffer, fwd, GNUNET_NO);
2780 * Notify other peers on a connection of a broken link. Mark connections
2781 * to destroy after all traffic has been sent.
2783 * @param c Connection on which there has been a disconnection.
2784 * @param peer Peer that disconnected.
2787 GCC_notify_broken (struct CadetConnection *c,
2788 struct CadetPeer *peer)
2792 LOG (GNUNET_ERROR_TYPE_DEBUG,
2793 " notify broken on %s due to %s disconnect\n",
2794 GCC_2s (c), GCP_2s (peer));
2796 fwd = peer == get_prev_hop (c);
2798 if (GNUNET_YES == GCC_is_terminal (c, fwd))
2800 /* Local shutdown, no one to notify about this. */
2804 if (GNUNET_NO == c->destroy)
2805 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
2807 /* Connection will have at least one pending message
2808 * (the one we just scheduled), so no point in checking whether to
2809 * destroy immediately. */
2810 c->destroy = GNUNET_YES;
2811 c->state = CADET_CONNECTION_DESTROYED;
2814 * Cancel all queues, if no message is left, connection will be destroyed.
2816 connection_cancel_queues (c, !fwd);
2823 * Is this peer the first one on the connection?
2825 * @param c Connection.
2826 * @param fwd Is this about fwd traffic?
2828 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
2831 GCC_is_origin (struct CadetConnection *c, int fwd)
2833 if (!fwd && c->path->length - 1 == c->own_pos )
2835 if (fwd && 0 == c->own_pos)
2842 * Is this peer the last one on the connection?
2844 * @param c Connection.
2845 * @param fwd Is this about fwd traffic?
2846 * Note that the ROOT is the terminal for BCK traffic!
2848 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
2851 GCC_is_terminal (struct CadetConnection *c, int fwd)
2853 return GCC_is_origin (c, !fwd);
2858 * See if we are allowed to send by the next hop in the given direction.
2860 * @param c Connection.
2861 * @param fwd Is this about fwd traffic?
2863 * @return #GNUNET_YES in case it's OK to send.
2866 GCC_is_sendable (struct CadetConnection *c, int fwd)
2868 struct CadetFlowControl *fc;
2870 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking sendability of %s traffic on %s\n",
2871 GC_f2s (fwd), GCC_2s (c));
2877 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2878 LOG (GNUNET_ERROR_TYPE_DEBUG,
2879 " last ack recv: %u, last pid sent: %u\n",
2880 fc->last_ack_recv, fc->last_pid_sent);
2881 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2883 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
2886 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
2892 * Check if this connection is a direct one (never trim a direct connection).
2894 * @param c Connection.
2896 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
2899 GCC_is_direct (struct CadetConnection *c)
2901 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
2905 * Sends an already built message on a connection, properly registering
2906 * all used resources.
2908 * @param message Message to send. Function makes a copy of it.
2909 * If message is not hop-by-hop, decrements TTL of copy.
2910 * @param payload_type Type of payload, in case the message is encrypted.
2911 * @param c Connection on which this message is transmitted.
2912 * @param fwd Is this a fwd message?
2913 * @param force Force the connection to accept the message (buffer overfill).
2914 * @param cont Continuation called once message is sent. Can be NULL.
2915 * @param cont_cls Closure for @c cont.
2917 * @return Handle to cancel the message before it's sent.
2918 * NULL on error or if @c cont is NULL.
2919 * Invalid on @c cont call.
2921 struct CadetConnectionQueue *
2922 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2923 uint16_t payload_type, uint32_t payload_id,
2924 struct CadetConnection *c, int fwd, int force,
2925 GCC_sent cont, void *cont_cls)
2927 struct CadetFlowControl *fc;
2928 struct CadetConnectionQueue *q;
2934 size = ntohs (message->size);
2935 data = GNUNET_malloc (size);
2936 memcpy (data, message, size);
2937 type = ntohs (message->type);
2938 LOG (GNUNET_ERROR_TYPE_INFO, "--> %s (%s %u) on connection %s (%u bytes)\n",
2939 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), size);
2941 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2942 droppable = GNUNET_NO == force;
2945 struct GNUNET_CADET_Encrypted *emsg;
2946 struct GNUNET_CADET_KX *kmsg;
2947 struct GNUNET_CADET_ACK *amsg;
2948 struct GNUNET_CADET_Poll *pmsg;
2949 struct GNUNET_CADET_ConnectionDestroy *dmsg;
2950 struct GNUNET_CADET_ConnectionBroken *bmsg;
2953 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
2954 emsg = (struct GNUNET_CADET_Encrypted *) data;
2955 ttl = ntohl (emsg->ttl);
2958 GNUNET_break_op (0);
2963 emsg->ttl = htonl (ttl - 1);
2964 emsg->pid = htonl (0);
2965 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
2966 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
2967 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
2968 if (GNUNET_YES == droppable)
2974 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
2976 if (GC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
2978 GCC_start_poll (c, fwd);
2982 case GNUNET_MESSAGE_TYPE_CADET_KX:
2983 kmsg = (struct GNUNET_CADET_KX *) data;
2987 case GNUNET_MESSAGE_TYPE_CADET_ACK:
2988 amsg = (struct GNUNET_CADET_ACK *) data;
2990 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
2991 droppable = GNUNET_NO;
2994 case GNUNET_MESSAGE_TYPE_CADET_POLL:
2995 pmsg = (struct GNUNET_CADET_Poll *) data;
2997 LOG (GNUNET_ERROR_TYPE_DEBUG, " poll %u\n", ntohl (pmsg->pid));
2998 droppable = GNUNET_NO;
3001 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
3002 dmsg = (struct GNUNET_CADET_ConnectionDestroy *) data;
3006 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
3007 bmsg = (struct GNUNET_CADET_ConnectionBroken *) data;
3011 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
3012 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
3021 if (fc->queue_n > fc->queue_max && droppable)
3023 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
3026 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue full: %u/%u\n",
3027 fc->queue_n, fc->queue_max);
3028 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
3033 return NULL; /* Drop this message */
3036 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %s %u\n",
3037 GCC_2s (c), c->pending_messages);
3038 c->pending_messages++;
3040 q = GNUNET_new (struct CadetConnectionQueue);
3041 q->forced = !droppable;
3042 q->q = GCP_queue_add (get_hop (c, fwd), data, type, payload_type, payload_id,
3043 size, c, fwd, &conn_message_sent, q);
3046 LOG (GNUNET_ERROR_TYPE_DEBUG, "dropping msg on %s, NULL q\n", GCC_2s (c));
3052 q->cont_cls = cont_cls;
3053 return (NULL == cont) ? NULL : q;
3058 * Cancel a previously sent message while it's in the queue.
3060 * ONLY can be called before the continuation given to the send function
3061 * is called. Once the continuation is called, the message is no longer in the
3064 * @param q Handle to the queue.
3067 GCC_cancel (struct CadetConnectionQueue *q)
3069 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GMC cancel message\n");
3071 /* queue destroy calls message_sent, which calls q->cont and frees q */
3072 GCP_queue_destroy (q->q, GNUNET_YES, GNUNET_NO, 0);
3077 * Sends a CREATE CONNECTION message for a path to a peer.
3078 * Changes the connection and tunnel states if necessary.
3080 * @param connection Connection to create.
3083 GCC_send_create (struct CadetConnection *connection)
3085 enum CadetTunnelCState state;
3088 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3089 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
3091 LOG (GNUNET_ERROR_TYPE_INFO, "===> %s on connection %s (%u bytes)\n",
3092 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE),
3093 GCC_2s (connection), size);
3094 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3095 connection, connection->pending_messages);
3096 connection->pending_messages++;
3098 connection->maintenance_q =
3099 GCP_queue_add (get_next_hop (connection), NULL,
3100 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, 0, 0,
3101 size, connection, GNUNET_YES, &conn_message_sent, NULL);
3103 state = GCT_get_cstate (connection->t);
3104 if (CADET_TUNNEL_SEARCHING == state || CADET_TUNNEL_NEW == state)
3105 GCT_change_cstate (connection->t, CADET_TUNNEL_WAITING);
3106 if (CADET_CONNECTION_NEW == connection->state)
3107 connection_change_state (connection, CADET_CONNECTION_SENT);
3112 * Send a message to all peers in this connection that the connection
3113 * is no longer valid.
3115 * If some peer should not receive the message, it should be zero'ed out
3116 * before calling this function.
3118 * @param c The connection whose peers to notify.
3121 GCC_send_destroy (struct CadetConnection *c)
3123 struct GNUNET_CADET_ConnectionDestroy msg;
3125 if (GNUNET_YES == c->destroy)
3128 msg.header.size = htons (sizeof (msg));
3129 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
3131 LOG (GNUNET_ERROR_TYPE_DEBUG,
3132 " sending connection destroy for connection %s\n",
3135 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3136 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, 0, 0, c,
3137 GNUNET_YES, GNUNET_YES,
3139 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3140 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, 0, 0, c,
3141 GNUNET_NO, GNUNET_YES,
3143 c->destroy = GNUNET_YES;
3144 c->state = CADET_CONNECTION_DESTROYED;
3149 * @brief Start a polling timer for the connection.
3151 * When a neighbor does not accept more traffic on the connection it could be
3152 * caused by a simple congestion or by a lost ACK. Polling enables to check
3153 * for the lastest ACK status for a connection.
3155 * @param c Connection.
3156 * @param fwd Should we poll in the FWD direction?
3159 GCC_start_poll (struct CadetConnection *c, int fwd)
3161 struct CadetFlowControl *fc;
3163 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3164 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL %s requested\n",
3166 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task || NULL != fc->poll_msg)
3168 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** not needed (%u, %p)\n",
3169 fc->poll_task, fc->poll_msg);
3172 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL started on request\n");
3173 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
3180 * @brief Stop polling a connection for ACKs.
3182 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3184 * @param c Connection.
3185 * @param fwd Should we stop the poll in the FWD direction?
3188 GCC_stop_poll (struct CadetConnection *c, int fwd)
3190 struct CadetFlowControl *fc;
3192 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3193 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
3195 GNUNET_SCHEDULER_cancel (fc->poll_task);
3196 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
3201 * Get a (static) string for a connection.
3203 * @param c Connection.
3206 GCC_2s (const struct CadetConnection *c)
3213 static char buf[128];
3215 sprintf (buf, "%s (->%s)",
3216 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3219 return GNUNET_h2s (GC_h2hc (&c->id));
3224 * Log all possible info about the connection state.
3226 * @param c Connection to debug.
3227 * @param level Debug level to use.
3230 GCC_debug (const struct CadetConnection *c, enum GNUNET_ErrorType level)
3235 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
3237 __FILE__, __FUNCTION__, __LINE__);
3243 LOG2 (level, "CCC DEBUG NULL CONNECTION\n");
3247 LOG2 (level, "CCC DEBUG CONNECTION %s\n", GCC_2s (c));
3248 s = path_2s (c->path);
3249 LOG2 (level, "CCC path %s, own pos: %u\n", s, c->own_pos);
3251 LOG2 (level, "CCC state: %s, destroy: %u\n",
3252 GCC_state2s (c->state), c->destroy);
3253 LOG2 (level, "CCC pending messages: %u\n", c->pending_messages);
3254 if (NULL != c->perf)
3255 LOG2 (level, "CCC us/byte: %f\n", c->perf->avg);
3257 LOG2 (level, "CCC FWD flow control:\n");
3258 LOG2 (level, "CCC queue: %u/%u\n", c->fwd_fc.queue_n, c->fwd_fc.queue_max);
3259 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3260 c->fwd_fc.last_pid_sent, c->fwd_fc.last_pid_recv);
3261 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3262 c->fwd_fc.last_ack_sent, c->fwd_fc.last_ack_recv);
3263 LOG2 (level, "CCC POLL: task %d, msg %p, msg_ack %p)\n",
3264 c->fwd_fc.poll_task, c->fwd_fc.poll_msg, c->fwd_fc.ack_msg);
3266 LOG2 (level, "CCC BCK flow control:\n");
3267 LOG2 (level, "CCC queue: %u/%u\n", c->bck_fc.queue_n, c->bck_fc.queue_max);
3268 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3269 c->bck_fc.last_pid_sent, c->bck_fc.last_pid_recv);
3270 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3271 c->bck_fc.last_ack_sent, c->bck_fc.last_ack_recv);
3272 LOG2 (level, "CCC POLL: task %d, msg %p, msg_ack %p)\n",
3273 c->bck_fc.poll_task, c->bck_fc.poll_msg, c->bck_fc.ack_msg);
3275 LOG2 (level, "CCC DEBUG CONNECTION END\n");