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 * Resend all queued messages for a connection on other connections of the
1262 * same tunnel, if possible. The connection WILL BE DESTROYED by this function.
1264 * @param c Connection whose messages to resend.
1265 * @param fwd Resend fwd messages?
1268 resend_messages_and_destroy (struct CadetConnection *c, int fwd)
1270 struct GNUNET_MessageHeader *out_msg;
1271 struct CadetTunnel *t = c->t;
1272 struct CadetPeer *neighbor;
1275 c->state = CADET_CONNECTION_DESTROYED;
1276 c->destroy = GNUNET_YES;
1278 destroyed = GNUNET_NO;
1279 neighbor = get_hop (c, fwd);
1281 while (NULL != (out_msg = GCP_connection_pop (neighbor, c, &destroyed)))
1284 GCT_resend_message (out_msg, t);
1285 GNUNET_free (out_msg);
1288 /* All pending messages should have been popped,
1289 * and the connection destroyed by the continuation.
1291 if (GNUNET_YES != destroyed)
1294 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1295 GCT_debug (t, GNUNET_ERROR_TYPE_ERROR);
1302 * Timeout function due to lack of keepalive/traffic from the owner.
1303 * Destroys connection if called.
1305 * @param cls Closure (connection to destroy).
1306 * @param tc TaskContext.
1309 connection_fwd_timeout (void *cls,
1310 const struct GNUNET_SCHEDULER_TaskContext *tc)
1312 struct CadetConnection *c = cls;
1314 c->fwd_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1315 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1318 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s FWD timed out. Destroying.\n",
1320 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1322 if (GCC_is_origin (c, GNUNET_YES)) /* If local, leave. */
1328 /* If dest, salvage queued traffic. */
1329 if (GCC_is_origin (c, GNUNET_NO) && 0 < c->bck_fc.queue_n)
1331 resend_messages_and_destroy (c, GNUNET_NO);
1340 * Timeout function due to lack of keepalive/traffic from the destination.
1341 * Destroys connection if called.
1343 * FIXME refactor and merge with connection_fwd_timeout.
1345 * @param cls Closure (connection to destroy).
1346 * @param tc TaskContext
1349 connection_bck_timeout (void *cls,
1350 const struct GNUNET_SCHEDULER_TaskContext *tc)
1352 struct CadetConnection *c = cls;
1354 c->bck_maintenance_task = GNUNET_SCHEDULER_NO_TASK;
1355 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1358 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s BCK timed out. Destroying.\n",
1361 if (GCC_is_origin (c, GNUNET_NO)) /* If local, leave. */
1367 /* If dest, salvage queued traffic. */
1368 if (GCC_is_origin (c, GNUNET_YES) && 0 < c->fwd_fc.queue_n)
1370 resend_messages_and_destroy (c, GNUNET_YES);
1379 * Resets the connection timeout task, some other message has done the
1381 * - For the first peer on the direction this means to send
1382 * a keepalive or a path confirmation message (either create or ACK).
1383 * - For all other peers, this means to destroy the connection,
1384 * due to lack of activity.
1385 * Starts the timeout if no timeout was running (connection just created).
1387 * @param c Connection whose timeout to reset.
1388 * @param fwd Is this forward?
1390 * TODO use heap to improve efficiency of scheduler.
1393 connection_reset_timeout (struct CadetConnection *c, int fwd)
1395 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1397 if (GCC_is_origin (c, fwd)) /* Startpoint */
1399 schedule_next_keepalive (c, fwd);
1401 else /* Relay, endpoint. */
1403 struct GNUNET_TIME_Relative delay;
1404 GNUNET_SCHEDULER_TaskIdentifier *ti;
1405 GNUNET_SCHEDULER_Task f;
1407 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1409 if (GNUNET_SCHEDULER_NO_TASK != *ti)
1410 GNUNET_SCHEDULER_cancel (*ti);
1411 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1412 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1413 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1419 * Add the connection to the list of both neighbors.
1421 * @param c Connection.
1423 * @return #GNUNET_OK if everything went fine
1424 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1427 register_neighbors (struct CadetConnection *c)
1429 struct CadetPeer *next_peer;
1430 struct CadetPeer *prev_peer;
1432 next_peer = get_next_hop (c);
1433 prev_peer = get_prev_hop (c);
1435 LOG (GNUNET_ERROR_TYPE_DEBUG, "register neighbors for connection %s\n",
1437 path_debug (c->path);
1438 LOG (GNUNET_ERROR_TYPE_DEBUG, "own pos %u\n", c->own_pos);
1439 LOG (GNUNET_ERROR_TYPE_DEBUG, "putting connection %s to next peer %p\n",
1440 GCC_2s (c), next_peer);
1441 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n", next_peer, GCP_2s (next_peer));
1442 LOG (GNUNET_ERROR_TYPE_DEBUG, "putting connection %s to prev peer %p\n",
1443 GCC_2s (c), prev_peer);
1444 LOG (GNUNET_ERROR_TYPE_DEBUG, "prev peer %p %s\n", prev_peer, GCP_2s (prev_peer));
1446 if (GNUNET_NO == GCP_is_neighbor (next_peer)
1447 || GNUNET_NO == GCP_is_neighbor (prev_peer))
1449 if (GCC_is_origin (c, GNUNET_YES))
1450 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1451 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1453 LOG (GNUNET_ERROR_TYPE_DEBUG, " register neighbors failed\n");
1454 LOG (GNUNET_ERROR_TYPE_DEBUG, " prev: %s, neighbor?: %d\n",
1455 GCP_2s (prev_peer), GCP_is_neighbor (prev_peer));
1456 LOG (GNUNET_ERROR_TYPE_DEBUG, " next: %s, neighbor?: %d\n",
1457 GCP_2s (next_peer), GCP_is_neighbor (next_peer));
1458 return GNUNET_SYSERR;
1461 GCP_add_connection (next_peer, c);
1462 GCP_add_connection (prev_peer, c);
1469 * Remove the connection from the list of both neighbors.
1471 * @param c Connection.
1474 unregister_neighbors (struct CadetConnection *c)
1476 struct CadetPeer *peer;
1478 peer = get_next_hop (c);
1479 if (GNUNET_OK != GCP_remove_connection (peer, c))
1481 GNUNET_assert (CADET_CONNECTION_NEW == c->state
1482 || CADET_CONNECTION_DESTROYED <= c->state);
1483 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate: %u\n", c->state);
1484 if (NULL != c->t) GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1487 peer = get_prev_hop (c);
1488 if (GNUNET_OK != GCP_remove_connection (peer, c))
1490 GNUNET_assert (CADET_CONNECTION_NEW == c->state
1491 || CADET_CONNECTION_DESTROYED <= c->state);
1492 LOG (GNUNET_ERROR_TYPE_DEBUG, " cstate: %u\n", c->state);
1493 if (NULL != c->t) GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1499 * Bind the connection to the peer and the tunnel to that peer.
1501 * If the peer has no tunnel, create one. Update tunnel and connection
1502 * data structres to reflect new status.
1504 * @param c Connection.
1508 add_to_peer (struct CadetConnection *c, struct CadetPeer *peer)
1510 GCP_add_tunnel (peer);
1511 c->t = GCP_get_tunnel (peer);
1512 GCT_add_connection (c->t, c);
1517 * Log receipt of message on stderr (INFO level).
1519 * @param message Message received.
1520 * @param peer Peer who sent the message.
1521 * @param hash Connection ID.
1524 log_message (const struct GNUNET_MessageHeader *message,
1525 const struct GNUNET_PeerIdentity *peer,
1526 const struct GNUNET_CADET_Hash *hash)
1528 LOG (GNUNET_ERROR_TYPE_INFO, "\n");
1529 LOG (GNUNET_ERROR_TYPE_INFO, "\n");
1530 LOG (GNUNET_ERROR_TYPE_INFO, "<-- %s on connection %s from %s\n",
1531 GC_m2s (ntohs (message->type)), GNUNET_h2s (GC_h2hc (hash)),
1535 /******************************************************************************/
1536 /******************************** API ***********************************/
1537 /******************************************************************************/
1540 * Core handler for connection creation.
1542 * @param cls Closure (unused).
1543 * @param peer Sender (neighbor).
1544 * @param message Message.
1546 * @return GNUNET_OK to keep the connection open,
1547 * GNUNET_SYSERR to close it (signal serious error)
1550 GCC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
1551 const struct GNUNET_MessageHeader *message)
1553 struct GNUNET_CADET_ConnectionCreate *msg;
1554 struct GNUNET_PeerIdentity *id;
1555 struct GNUNET_CADET_Hash *cid;
1556 struct CadetPeerPath *path;
1557 struct CadetPeer *dest_peer;
1558 struct CadetPeer *orig_peer;
1559 struct CadetConnection *c;
1560 unsigned int own_pos;
1564 size = ntohs (message->size);
1565 if (size < sizeof (struct GNUNET_CADET_ConnectionCreate))
1567 GNUNET_break_op (0);
1571 /* Calculate hops */
1572 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
1573 if (size % sizeof (struct GNUNET_PeerIdentity))
1575 GNUNET_break_op (0);
1578 size /= sizeof (struct GNUNET_PeerIdentity);
1581 GNUNET_break_op (0);
1584 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1586 /* Get parameters */
1587 msg = (struct GNUNET_CADET_ConnectionCreate *) message;
1589 log_message (message, peer, cid);
1590 id = (struct GNUNET_PeerIdentity *) &msg[1];
1591 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
1593 /* Create connection */
1594 c = connection_get (cid);
1597 path = path_build_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
1598 size, myid, &own_pos);
1604 GNUNET_break_op (0);
1605 path_destroy (path);
1608 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1609 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1610 c = GCC_new (cid, NULL, path, own_pos);
1613 if (path->length - 1 == own_pos)
1615 /* If we are destination, why did the creation fail? */
1617 path_destroy (path);
1620 send_broken_unknown (cid, &my_full_id,
1621 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
1623 path_destroy (path);
1626 GCP_add_path_to_all (path, GNUNET_NO);
1627 connection_reset_timeout (c, GNUNET_YES);
1631 path = path_duplicate (c->path);
1633 if (CADET_CONNECTION_NEW == c->state)
1634 connection_change_state (c, CADET_CONNECTION_SENT);
1636 /* Remember peers */
1637 dest_peer = GCP_get (&id[size - 1]);
1638 orig_peer = GCP_get (&id[0]);
1640 /* Is it a connection to us? */
1641 if (c->own_pos == path->length - 1)
1643 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1644 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
1646 add_to_peer (c, orig_peer);
1647 if (CADET_TUNNEL_NEW == GCT_get_cstate (c->t))
1648 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
1650 send_connection_ack (c, GNUNET_NO);
1651 if (CADET_CONNECTION_SENT == c->state)
1652 connection_change_state (c, CADET_CONNECTION_ACK);
1656 /* It's for somebody else! Retransmit. */
1657 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
1658 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1659 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
1660 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c,
1661 GNUNET_YES, GNUNET_YES,
1664 path_destroy (path);
1670 * Core handler for path confirmations.
1672 * @param cls closure
1673 * @param message message
1674 * @param peer peer identity this notification is about
1676 * @return GNUNET_OK to keep the connection open,
1677 * GNUNET_SYSERR to close it (signal serious error)
1680 GCC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
1681 const struct GNUNET_MessageHeader *message)
1683 struct GNUNET_CADET_ConnectionACK *msg;
1684 struct CadetConnection *c;
1685 struct CadetPeerPath *p;
1686 struct CadetPeer *pi;
1687 enum CadetConnectionState oldstate;
1690 msg = (struct GNUNET_CADET_ConnectionACK *) message;
1691 log_message (message, peer, &msg->cid);
1692 c = connection_get (&msg->cid);
1695 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1697 LOG (GNUNET_ERROR_TYPE_DEBUG, " don't know the connection!\n");
1698 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
1702 if (GNUNET_NO != c->destroy)
1704 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection being destroyed\n");
1708 oldstate = c->state;
1709 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
1710 pi = GCP_get (peer);
1711 if (get_next_hop (c) == pi)
1713 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
1715 if (CADET_CONNECTION_SENT == oldstate)
1716 connection_change_state (c, CADET_CONNECTION_ACK);
1718 else if (get_prev_hop (c) == pi)
1720 LOG (GNUNET_ERROR_TYPE_DEBUG, " FINAL ACK\n");
1722 connection_change_state (c, CADET_CONNECTION_READY);
1726 GNUNET_break_op (0);
1730 connection_reset_timeout (c, fwd);
1732 /* Add path to peers? */
1736 GCP_add_path_to_all (p, GNUNET_YES);
1743 /* Message for us as creator? */
1744 if (GCC_is_origin (c, GNUNET_YES))
1746 if (GNUNET_NO != fwd)
1748 GNUNET_break_op (0);
1751 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
1753 /* If just created, cancel the short timeout and start a long one */
1754 if (CADET_CONNECTION_SENT == oldstate)
1755 connection_reset_timeout (c, GNUNET_YES);
1757 /* Change connection state */
1758 connection_change_state (c, CADET_CONNECTION_READY);
1759 send_connection_ack (c, GNUNET_YES);
1761 /* Change tunnel state, trigger KX */
1762 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
1763 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
1768 /* Message for us as destination? */
1769 if (GCC_is_terminal (c, GNUNET_YES))
1771 if (GNUNET_YES != fwd)
1773 GNUNET_break_op (0);
1776 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
1778 /* If just created, cancel the short timeout and start a long one */
1779 if (CADET_CONNECTION_ACK == oldstate)
1780 connection_reset_timeout (c, GNUNET_NO);
1782 /* Change tunnel state */
1783 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
1784 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
1789 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1790 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
1791 GNUNET_YES, NULL, NULL));
1797 * Core handler for notifications of broken connections.
1799 * @param cls Closure (unused).
1800 * @param id Peer identity of sending neighbor.
1801 * @param message Message.
1803 * @return GNUNET_OK to keep the connection open,
1804 * GNUNET_SYSERR to close it (signal serious error)
1807 GCC_handle_broken (void* cls,
1808 const struct GNUNET_PeerIdentity* id,
1809 const struct GNUNET_MessageHeader* message)
1811 struct GNUNET_CADET_ConnectionBroken *msg;
1812 struct CadetConnection *c;
1813 struct CadetTunnel *t;
1817 msg = (struct GNUNET_CADET_ConnectionBroken *) message;
1818 log_message (message, id, &msg->cid);
1819 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1820 GNUNET_i2s (&msg->peer1));
1821 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
1822 GNUNET_i2s (&msg->peer2));
1823 c = connection_get (&msg->cid);
1826 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
1831 fwd = is_fwd (c, id);
1832 c->destroy = GNUNET_YES;
1833 if (GCC_is_terminal (c, fwd))
1835 struct CadetPeer *endpoint;
1839 /* A terminal connection should not have 't' set to NULL. */
1841 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1844 endpoint = GCP_get_short (c->path->peers[c->path->length - 1]);
1845 path_invalidate (c->path);
1846 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
1848 c->state = CADET_CONNECTION_BROKEN;
1849 GCT_remove_connection (t, c);
1852 pending = c->pending_messages;
1854 resend_messages_and_destroy (c, !fwd);
1860 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
1861 GNUNET_YES, NULL, NULL));
1862 connection_cancel_queues (c, !fwd);
1870 * Core handler for tunnel destruction
1872 * @param cls Closure (unused).
1873 * @param peer Peer identity of sending neighbor.
1874 * @param message Message.
1876 * @return GNUNET_OK to keep the connection open,
1877 * GNUNET_SYSERR to close it (signal serious error)
1880 GCC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
1881 const struct GNUNET_MessageHeader *message)
1883 struct GNUNET_CADET_ConnectionDestroy *msg;
1884 struct CadetConnection *c;
1887 msg = (struct GNUNET_CADET_ConnectionDestroy *) message;
1888 log_message (message, peer, &msg->cid);
1889 c = connection_get (&msg->cid);
1892 /* Probably already got the message from another path,
1893 * destroyed the tunnel and retransmitted to children.
1896 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
1898 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection unknown: already destroyed?\n");
1901 fwd = is_fwd (c, peer);
1902 if (GNUNET_SYSERR == fwd)
1904 GNUNET_break_op (0); /* FIXME */
1907 if (GNUNET_NO == GCC_is_terminal (c, fwd))
1908 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
1909 GNUNET_YES, NULL, NULL));
1910 else if (0 == c->pending_messages)
1912 LOG (GNUNET_ERROR_TYPE_DEBUG, " directly destroying connection!\n");
1916 c->destroy = GNUNET_YES;
1917 c->state = CADET_CONNECTION_DESTROYED;
1920 GCT_remove_connection (c->t, c);
1928 * Generic handler for cadet network encrypted traffic.
1930 * @param peer Peer identity this notification is about.
1931 * @param msg Encrypted message.
1933 * @return GNUNET_OK to keep the connection open,
1934 * GNUNET_SYSERR to close it (signal serious error)
1937 handle_cadet_encrypted (const struct GNUNET_PeerIdentity *peer,
1938 const struct GNUNET_CADET_Encrypted *msg)
1940 struct CadetConnection *c;
1941 struct CadetPeer *neighbor;
1942 struct CadetFlowControl *fc;
1943 GNUNET_PEER_Id peer_id;
1949 log_message (&msg->header, peer, &msg->cid);
1952 size = ntohs (msg->header.size);
1954 sizeof (struct GNUNET_CADET_Encrypted) +
1955 sizeof (struct GNUNET_MessageHeader))
1957 GNUNET_break_op (0);
1961 /* Check connection */
1962 c = connection_get (&msg->cid);
1965 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
1966 LOG (GNUNET_ERROR_TYPE_DEBUG, "enc on unknown connection %s\n",
1967 GNUNET_h2s (GC_h2hc (&msg->cid)));
1968 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
1972 LOG (GNUNET_ERROR_TYPE_DEBUG, " connection %s\n", GCC_2s (c));
1974 /* Check if origin is as expected */
1975 neighbor = get_prev_hop (c);
1976 peer_id = GNUNET_PEER_search (peer);
1977 if (peer_id == GCP_get_short_id (neighbor))
1983 neighbor = get_next_hop (c);
1984 if (peer_id == GCP_get_short_id (neighbor))
1990 /* Unexpected peer sending traffic on a connection. */
1991 GNUNET_break_op (0);
1997 fc = fwd ? &c->bck_fc : &c->fwd_fc;
1998 pid = ntohl (msg->pid);
1999 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u+)\n",
2000 pid, fc->last_pid_recv + 1);
2001 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
2003 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
2004 GNUNET_break_op (0);
2005 LOG (GNUNET_ERROR_TYPE_WARNING,
2006 "Received PID %u, (prev %u), ACK %u\n",
2007 pid, fc->last_pid_recv, fc->last_ack_sent);
2010 if (GNUNET_NO == GC_is_pid_bigger (pid, fc->last_pid_recv))
2012 GNUNET_STATISTICS_update (stats, "# duplicate PID", 1, GNUNET_NO);
2013 LOG (GNUNET_ERROR_TYPE_DEBUG,
2014 " PID %u not expected (%u+), dropping!\n",
2015 pid, fc->last_pid_recv + 1);
2018 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2019 connection_change_state (c, CADET_CONNECTION_READY);
2020 connection_reset_timeout (c, fwd);
2021 fc->last_pid_recv = pid;
2023 /* Is this message for us? */
2024 if (GCC_is_terminal (c, fwd))
2026 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2027 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
2031 GNUNET_break (GNUNET_NO != c->destroy);
2034 fc->last_pid_recv = pid;
2035 GCT_handle_encrypted (c->t, msg);
2036 GCC_send_ack (c, fwd, GNUNET_NO);
2040 /* Message not for us: forward to next hop */
2041 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2042 ttl = ntohl (msg->ttl);
2043 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
2046 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
2047 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
2048 GCC_send_ack (c, fwd, GNUNET_NO);
2052 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2053 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2054 GNUNET_NO, NULL, NULL));
2060 * Generic handler for cadet network encrypted traffic.
2062 * @param peer Peer identity this notification is about.
2063 * @param msg Encrypted message.
2065 * @return GNUNET_OK to keep the connection open,
2066 * GNUNET_SYSERR to close it (signal serious error)
2069 handle_cadet_kx (const struct GNUNET_PeerIdentity *peer,
2070 const struct GNUNET_CADET_KX *msg)
2072 struct CadetConnection *c;
2073 struct CadetPeer *neighbor;
2074 GNUNET_PEER_Id peer_id;
2078 log_message (&msg->header, peer, &msg->cid);
2081 size = ntohs (msg->header.size);
2083 sizeof (struct GNUNET_CADET_KX) +
2084 sizeof (struct GNUNET_MessageHeader))
2086 GNUNET_break_op (0);
2090 /* Check connection */
2091 c = connection_get (&msg->cid);
2094 GNUNET_STATISTICS_update (stats, "# unknown connection", 1, GNUNET_NO);
2095 LOG (GNUNET_ERROR_TYPE_DEBUG, "kx on unknown connection %s\n",
2096 GNUNET_h2s (GC_h2hc (&msg->cid)));
2097 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2100 LOG (GNUNET_ERROR_TYPE_DEBUG, " on connection %s\n", GCC_2s (c));
2102 /* Check if origin is as expected */
2103 neighbor = get_prev_hop (c);
2104 peer_id = GNUNET_PEER_search (peer);
2105 if (peer_id == GCP_get_short_id (neighbor))
2111 neighbor = get_next_hop (c);
2112 if (peer_id == GCP_get_short_id (neighbor))
2118 /* Unexpected peer sending traffic on a connection. */
2119 GNUNET_break_op (0);
2124 /* Count as connection confirmation. */
2125 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2127 connection_change_state (c, CADET_CONNECTION_READY);
2130 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2131 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2134 connection_reset_timeout (c, fwd);
2136 /* Is this message for us? */
2137 if (GCC_is_terminal (c, fwd))
2139 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2140 GNUNET_STATISTICS_update (stats, "# messages received", 1, GNUNET_NO);
2146 GCT_handle_kx (c->t, &msg[1].header);
2150 /* Message not for us: forward to next hop */
2151 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2152 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2153 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2154 GNUNET_NO, NULL, NULL));
2161 * Core handler for encrypted cadet network traffic (channel mgmt, data).
2163 * @param cls Closure (unused).
2164 * @param message Message received.
2165 * @param peer Peer who sent the message.
2167 * @return GNUNET_OK to keep the connection open,
2168 * GNUNET_SYSERR to close it (signal serious error)
2171 GCC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
2172 const struct GNUNET_MessageHeader *message)
2174 return handle_cadet_encrypted (peer,
2175 (struct GNUNET_CADET_Encrypted *)message);
2180 * Core handler for key exchange traffic (ephemeral key, ping, pong).
2182 * @param cls Closure (unused).
2183 * @param message Message received.
2184 * @param peer Peer who sent the message.
2186 * @return GNUNET_OK to keep the connection open,
2187 * GNUNET_SYSERR to close it (signal serious error)
2190 GCC_handle_kx (void *cls, const struct GNUNET_PeerIdentity *peer,
2191 const struct GNUNET_MessageHeader *message)
2193 return handle_cadet_kx (peer,
2194 (struct GNUNET_CADET_KX *) message);
2199 * Core handler for cadet network traffic point-to-point acks.
2201 * @param cls closure
2202 * @param message message
2203 * @param peer peer identity this notification is about
2205 * @return GNUNET_OK to keep the connection open,
2206 * GNUNET_SYSERR to close it (signal serious error)
2209 GCC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
2210 const struct GNUNET_MessageHeader *message)
2212 struct GNUNET_CADET_ACK *msg;
2213 struct CadetConnection *c;
2214 struct CadetFlowControl *fc;
2219 msg = (struct GNUNET_CADET_ACK *) message;
2220 log_message (message, peer, &msg->cid);
2221 c = connection_get (&msg->cid);
2224 GNUNET_STATISTICS_update (stats, "# ack on unknown connection", 1,
2226 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2230 /* Is this a forward or backward ACK? */
2231 id = GNUNET_PEER_search (peer);
2232 if (GCP_get_short_id (get_next_hop (c)) == id)
2234 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD ACK\n");
2238 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2240 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK ACK\n");
2246 GNUNET_break_op (0);
2250 ack = ntohl (msg->ack);
2251 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u (was %u)\n",
2252 ack, fc->last_ack_recv);
2253 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2254 fc->last_ack_recv = ack;
2256 /* Cancel polling if the ACK is big enough. */
2257 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task &&
2258 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2260 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2261 GNUNET_SCHEDULER_cancel (fc->poll_task);
2262 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
2263 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2266 connection_unlock_queue (c, fwd);
2273 * Core handler for cadet network traffic point-to-point ack polls.
2275 * @param cls closure
2276 * @param message message
2277 * @param peer peer identity this notification is about
2279 * @return GNUNET_OK to keep the connection open,
2280 * GNUNET_SYSERR to close it (signal serious error)
2283 GCC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
2284 const struct GNUNET_MessageHeader *message)
2286 struct GNUNET_CADET_Poll *msg;
2287 struct CadetConnection *c;
2288 struct CadetFlowControl *fc;
2293 msg = (struct GNUNET_CADET_Poll *) message;
2294 log_message (message, peer, &msg->cid);
2295 c = connection_get (&msg->cid);
2298 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2300 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL message on unknown connection %s!\n",
2301 GNUNET_h2s (GC_h2hc (&msg->cid)));
2302 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2306 /* Is this a forward or backward ACK?
2307 * Note: a poll should never be needed in a loopback case,
2308 * since there is no possiblility of packet loss there, so
2309 * this way of discerining FWD/BCK should not be a problem.
2311 id = GNUNET_PEER_search (peer);
2312 if (GCP_get_short_id (get_next_hop (c)) == id)
2314 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2317 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2319 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2324 GNUNET_break_op (0);
2328 pid = ntohl (msg->pid);
2329 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2330 fc->last_pid_recv = pid;
2331 fwd = fc == &c->bck_fc;
2332 GCC_send_ack (c, fwd, GNUNET_YES);
2339 * Send an ACK on the appropriate connection/channel, depending on
2340 * the direction and the position of the peer.
2342 * @param c Which connection to send the hop-by-hop ACK.
2343 * @param fwd Is this a fwd ACK? (will go dest->root).
2344 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2347 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
2349 unsigned int buffer;
2351 LOG (GNUNET_ERROR_TYPE_DEBUG,
2352 "GMC send %s ACK on %s\n",
2353 GC_f2s (fwd), GCC_2s (c));
2361 if (GNUNET_NO != c->destroy)
2363 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2367 /* Get available buffer space */
2368 if (GCC_is_terminal (c, fwd))
2370 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2371 buffer = GCT_get_channels_buffer (c->t);
2375 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2376 buffer = GCC_get_buffer (c, fwd);
2378 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2379 if (0 == buffer && GNUNET_NO == force)
2382 /* Send available buffer space */
2383 if (GCC_is_origin (c, fwd))
2385 GNUNET_assert (NULL != c->t);
2386 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2387 GCT_unchoke_channels (c->t);
2391 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2392 send_ack (c, buffer, fwd, force);
2398 * Initialize the connections subsystem
2400 * @param c Configuration handle.
2403 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2405 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2407 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2410 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2411 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2412 GNUNET_SCHEDULER_shutdown ();
2417 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2420 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2421 "CADET", "MAX_CONNECTIONS", "MISSING");
2422 GNUNET_SCHEDULER_shutdown ();
2427 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2428 &refresh_connection_time))
2430 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2431 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2432 GNUNET_SCHEDULER_shutdown ();
2435 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2436 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2441 * Destroy each connection on shutdown.
2443 * @param cls Closure (unused).
2444 * @param key Current key code (CID, unused).
2445 * @param value Value in the hash map (connection)
2447 * @return #GNUNET_YES, because we should continue to iterate,
2450 shutdown_iterator (void *cls,
2451 const struct GNUNET_HashCode *key,
2454 struct CadetConnection *c = value;
2462 * Shut down the connections subsystem.
2467 GNUNET_CONTAINER_multihashmap_iterate (connections, &shutdown_iterator, NULL);
2468 GNUNET_CONTAINER_multihashmap_destroy (connections);
2474 * Create a connection.
2476 * @param cid Connection ID (either created locally or imposed remotely).
2477 * @param t Tunnel this connection belongs to (or NULL);
2478 * @param path Path this connection has to use (copy is made).
2479 * @param own_pos Own position in the @c path path.
2481 * @return Newly created connection, NULL in case of error (own id not in path).
2483 struct CadetConnection *
2484 GCC_new (const struct GNUNET_CADET_Hash *cid,
2485 struct CadetTunnel *t,
2486 struct CadetPeerPath *path,
2487 unsigned int own_pos)
2489 struct CadetConnection *c;
2490 struct CadetPeerPath *p;
2492 p = path_duplicate (path);
2493 c = GNUNET_new (struct CadetConnection);
2495 GNUNET_assert (GNUNET_OK ==
2496 GNUNET_CONTAINER_multihashmap_put (connections,
2498 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2499 fc_init (&c->fwd_fc);
2500 fc_init (&c->bck_fc);
2505 GNUNET_assert (own_pos <= p->length - 1);
2506 c->own_pos = own_pos;
2510 if (GNUNET_OK != register_neighbors (c))
2514 path_invalidate (c->path);
2527 GCC_destroy (struct CadetConnection *c)
2535 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
2536 return; /* -> message_sent -> GCC_destroy. Don't loop. */
2539 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying connection %s\n", GCC_2s (c));
2540 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc's f: %p, b: %p\n",
2541 &c->fwd_fc, &c->bck_fc);
2542 LOG (GNUNET_ERROR_TYPE_DEBUG, " fc tasks f: %u, b: %u\n",
2543 c->fwd_fc.poll_task, c->bck_fc.poll_task);
2545 /* Cancel all traffic */
2546 if (NULL != c->path)
2548 connection_cancel_queues (c, GNUNET_YES);
2549 connection_cancel_queues (c, GNUNET_NO);
2550 unregister_neighbors (c);
2553 /* Cancel maintainance task (keepalive/timeout) */
2554 if (NULL != c->fwd_fc.poll_msg)
2556 GCC_cancel (c->fwd_fc.poll_msg);
2557 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg FWD canceled\n");
2559 if (NULL != c->bck_fc.poll_msg)
2561 GCC_cancel (c->bck_fc.poll_msg);
2562 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL msg BCK canceled\n");
2565 /* Delete from tunnel */
2567 GCT_remove_connection (c->t, c);
2569 if (GNUNET_NO == GCC_is_origin (c, GNUNET_YES) && NULL != c->path)
2570 path_destroy (c->path);
2571 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_maintenance_task)
2572 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2573 if (GNUNET_SCHEDULER_NO_TASK != c->bck_maintenance_task)
2574 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2575 if (GNUNET_SCHEDULER_NO_TASK != c->fwd_fc.poll_task)
2577 GNUNET_SCHEDULER_cancel (c->fwd_fc.poll_task);
2578 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL FWD canceled\n");
2580 if (GNUNET_SCHEDULER_NO_TASK != c->bck_fc.poll_task)
2582 GNUNET_SCHEDULER_cancel (c->bck_fc.poll_task);
2583 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL BCK canceled\n");
2586 GNUNET_break (GNUNET_YES ==
2587 GNUNET_CONTAINER_multihashmap_remove (connections,
2590 GNUNET_STATISTICS_update (stats, "# connections", -1, GNUNET_NO);
2595 * Get the connection ID.
2597 * @param c Connection to get the ID from.
2599 * @return ID of the connection.
2601 const struct GNUNET_CADET_Hash *
2602 GCC_get_id (const struct CadetConnection *c)
2609 * Get the connection ID.
2611 * @param c Connection to get the ID from.
2613 * @return ID of the connection.
2615 const struct GNUNET_HashCode *
2616 GCC_get_h (const struct CadetConnection *c)
2618 return GC_h2hc (&c->id);
2623 * Get the connection path.
2625 * @param c Connection to get the path from.
2627 * @return path used by the connection.
2629 const struct CadetPeerPath *
2630 GCC_get_path (const struct CadetConnection *c)
2632 if (GNUNET_NO == c->destroy)
2639 * Get the connection state.
2641 * @param c Connection to get the state from.
2643 * @return state of the connection.
2645 enum CadetConnectionState
2646 GCC_get_state (const struct CadetConnection *c)
2652 * Get the connection tunnel.
2654 * @param c Connection to get the tunnel from.
2656 * @return tunnel of the connection.
2658 struct CadetTunnel *
2659 GCC_get_tunnel (const struct CadetConnection *c)
2666 * Get free buffer space in a connection.
2668 * @param c Connection.
2669 * @param fwd Is query about FWD traffic?
2671 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2674 GCC_get_buffer (struct CadetConnection *c, int fwd)
2676 struct CadetFlowControl *fc;
2678 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2680 return (fc->queue_max - fc->queue_n);
2684 * Get how many messages have we allowed to send to us from a direction.
2686 * @param c Connection.
2687 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2689 * @return last_ack_sent - last_pid_recv
2692 GCC_get_allowed (struct CadetConnection *c, int fwd)
2694 struct CadetFlowControl *fc;
2696 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2697 if (GC_is_pid_bigger (fc->last_pid_recv, fc->last_ack_sent))
2701 return (fc->last_ack_sent - fc->last_pid_recv);
2705 * Get messages queued in a connection.
2707 * @param c Connection.
2708 * @param fwd Is query about FWD traffic?
2710 * @return Number of messages queued.
2713 GCC_get_qn (struct CadetConnection *c, int fwd)
2715 struct CadetFlowControl *fc;
2717 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2724 * Get next PID to use.
2726 * @param c Connection.
2727 * @param fwd Is query about FWD traffic?
2729 * @return Last PID used + 1.
2732 GCC_get_pid (struct CadetConnection *c, int fwd)
2734 struct CadetFlowControl *fc;
2736 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2738 return fc->last_pid_sent + 1;
2743 * Allow the connection to advertise a buffer of the given size.
2745 * The connection will send an @c fwd ACK message (so: in direction !fwd)
2746 * allowing up to last_pid_recv + buffer.
2748 * @param c Connection.
2749 * @param buffer How many more messages the connection can accept.
2750 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
2753 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
2755 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
2756 GCC_2s (c), buffer, GC_f2s (fwd));
2757 send_ack (c, buffer, fwd, GNUNET_NO);
2762 * Notify other peers on a connection of a broken link. Mark connections
2763 * to destroy after all traffic has been sent.
2765 * @param c Connection on which there has been a disconnection.
2766 * @param peer Peer that disconnected.
2769 GCC_notify_broken (struct CadetConnection *c,
2770 struct CadetPeer *peer)
2774 LOG (GNUNET_ERROR_TYPE_DEBUG,
2775 " notify broken on %s due to %s disconnect\n",
2776 GCC_2s (c), GCP_2s (peer));
2778 fwd = peer == get_prev_hop (c);
2780 if (GNUNET_YES == GCC_is_terminal (c, fwd))
2782 /* Local shutdown, no one to notify about this. */
2786 if (GNUNET_NO == c->destroy)
2787 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
2789 /* Connection will have at least one pending message
2790 * (the one we just scheduled), so no point in checking whether to
2791 * destroy immediately. */
2792 c->destroy = GNUNET_YES;
2793 c->state = CADET_CONNECTION_DESTROYED;
2796 * Cancel all queues, if no message is left, connection will be destroyed.
2798 connection_cancel_queues (c, !fwd);
2805 * Is this peer the first one on the connection?
2807 * @param c Connection.
2808 * @param fwd Is this about fwd traffic?
2810 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
2813 GCC_is_origin (struct CadetConnection *c, int fwd)
2815 if (!fwd && c->path->length - 1 == c->own_pos )
2817 if (fwd && 0 == c->own_pos)
2824 * Is this peer the last one on the connection?
2826 * @param c Connection.
2827 * @param fwd Is this about fwd traffic?
2828 * Note that the ROOT is the terminal for BCK traffic!
2830 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
2833 GCC_is_terminal (struct CadetConnection *c, int fwd)
2835 return GCC_is_origin (c, !fwd);
2840 * See if we are allowed to send by the next hop in the given direction.
2842 * @param c Connection.
2843 * @param fwd Is this about fwd traffic?
2845 * @return #GNUNET_YES in case it's OK to send.
2848 GCC_is_sendable (struct CadetConnection *c, int fwd)
2850 struct CadetFlowControl *fc;
2852 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking sendability of %s traffic on %s\n",
2853 GC_f2s (fwd), GCC_2s (c));
2859 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2860 LOG (GNUNET_ERROR_TYPE_DEBUG,
2861 " last ack recv: %u, last pid sent: %u\n",
2862 fc->last_ack_recv, fc->last_pid_sent);
2863 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2865 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
2868 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
2874 * Check if this connection is a direct one (never trim a direct connection).
2876 * @param c Connection.
2878 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
2881 GCC_is_direct (struct CadetConnection *c)
2883 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
2887 * Sends an already built message on a connection, properly registering
2888 * all used resources.
2890 * @param message Message to send. Function makes a copy of it.
2891 * If message is not hop-by-hop, decrements TTL of copy.
2892 * @param payload_type Type of payload, in case the message is encrypted.
2893 * @param c Connection on which this message is transmitted.
2894 * @param fwd Is this a fwd message?
2895 * @param force Force the connection to accept the message (buffer overfill).
2896 * @param cont Continuation called once message is sent. Can be NULL.
2897 * @param cont_cls Closure for @c cont.
2899 * @return Handle to cancel the message before it's sent.
2900 * NULL on error or if @c cont is NULL.
2901 * Invalid on @c cont call.
2903 struct CadetConnectionQueue *
2904 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2905 uint16_t payload_type, uint32_t payload_id,
2906 struct CadetConnection *c, int fwd, int force,
2907 GCC_sent cont, void *cont_cls)
2909 struct CadetFlowControl *fc;
2910 struct CadetConnectionQueue *q;
2916 size = ntohs (message->size);
2917 data = GNUNET_malloc (size);
2918 memcpy (data, message, size);
2919 type = ntohs (message->type);
2920 LOG (GNUNET_ERROR_TYPE_INFO, "--> %s (%s %u) on connection %s (%u bytes)\n",
2921 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), size);
2923 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2924 droppable = GNUNET_NO == force;
2927 struct GNUNET_CADET_Encrypted *emsg;
2928 struct GNUNET_CADET_KX *kmsg;
2929 struct GNUNET_CADET_ACK *amsg;
2930 struct GNUNET_CADET_Poll *pmsg;
2931 struct GNUNET_CADET_ConnectionDestroy *dmsg;
2932 struct GNUNET_CADET_ConnectionBroken *bmsg;
2935 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
2936 emsg = (struct GNUNET_CADET_Encrypted *) data;
2937 ttl = ntohl (emsg->ttl);
2940 GNUNET_break_op (0);
2945 emsg->ttl = htonl (ttl - 1);
2946 emsg->pid = htonl (0);
2947 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
2948 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
2949 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
2950 if (GNUNET_YES == droppable)
2956 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
2958 if (GC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
2960 GCC_start_poll (c, fwd);
2964 case GNUNET_MESSAGE_TYPE_CADET_KX:
2965 kmsg = (struct GNUNET_CADET_KX *) data;
2969 case GNUNET_MESSAGE_TYPE_CADET_ACK:
2970 amsg = (struct GNUNET_CADET_ACK *) data;
2972 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
2973 droppable = GNUNET_NO;
2976 case GNUNET_MESSAGE_TYPE_CADET_POLL:
2977 pmsg = (struct GNUNET_CADET_Poll *) data;
2979 LOG (GNUNET_ERROR_TYPE_DEBUG, " poll %u\n", ntohl (pmsg->pid));
2980 droppable = GNUNET_NO;
2983 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
2984 dmsg = (struct GNUNET_CADET_ConnectionDestroy *) data;
2988 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
2989 bmsg = (struct GNUNET_CADET_ConnectionBroken *) data;
2993 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
2994 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
3003 if (fc->queue_n > fc->queue_max && droppable)
3005 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
3008 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue full: %u/%u\n",
3009 fc->queue_n, fc->queue_max);
3010 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
3015 return NULL; /* Drop this message */
3018 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %s %u\n",
3019 GCC_2s (c), c->pending_messages);
3020 c->pending_messages++;
3022 q = GNUNET_new (struct CadetConnectionQueue);
3023 q->forced = !droppable;
3024 q->q = GCP_queue_add (get_hop (c, fwd), data, type, payload_type, payload_id,
3025 size, c, fwd, &conn_message_sent, q);
3028 LOG (GNUNET_ERROR_TYPE_DEBUG, "dropping msg on %s, NULL q\n", GCC_2s (c));
3034 q->cont_cls = cont_cls;
3035 return (NULL == cont) ? NULL : q;
3040 * Cancel a previously sent message while it's in the queue.
3042 * ONLY can be called before the continuation given to the send function
3043 * is called. Once the continuation is called, the message is no longer in the
3046 * @param q Handle to the queue.
3049 GCC_cancel (struct CadetConnectionQueue *q)
3051 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GMC cancel message\n");
3053 /* queue destroy calls message_sent, which calls q->cont and frees q */
3054 GCP_queue_destroy (q->q, GNUNET_YES, GNUNET_NO, 0);
3059 * Sends a CREATE CONNECTION message for a path to a peer.
3060 * Changes the connection and tunnel states if necessary.
3062 * @param connection Connection to create.
3065 GCC_send_create (struct CadetConnection *connection)
3067 enum CadetTunnelCState state;
3070 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3071 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
3073 LOG (GNUNET_ERROR_TYPE_INFO, "===> %s on connection %s (%u bytes)\n",
3074 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE),
3075 GCC_2s (connection), size);
3076 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3077 connection, connection->pending_messages);
3078 connection->pending_messages++;
3080 connection->maintenance_q =
3081 GCP_queue_add (get_next_hop (connection), NULL,
3082 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, 0, 0,
3083 size, connection, GNUNET_YES, &conn_message_sent, NULL);
3085 state = GCT_get_cstate (connection->t);
3086 if (CADET_TUNNEL_SEARCHING == state || CADET_TUNNEL_NEW == state)
3087 GCT_change_cstate (connection->t, CADET_TUNNEL_WAITING);
3088 if (CADET_CONNECTION_NEW == connection->state)
3089 connection_change_state (connection, CADET_CONNECTION_SENT);
3094 * Send a message to all peers in this connection that the connection
3095 * is no longer valid.
3097 * If some peer should not receive the message, it should be zero'ed out
3098 * before calling this function.
3100 * @param c The connection whose peers to notify.
3103 GCC_send_destroy (struct CadetConnection *c)
3105 struct GNUNET_CADET_ConnectionDestroy msg;
3107 if (GNUNET_YES == c->destroy)
3110 msg.header.size = htons (sizeof (msg));
3111 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
3113 LOG (GNUNET_ERROR_TYPE_DEBUG,
3114 " sending connection destroy for connection %s\n",
3117 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3118 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, 0, 0, c,
3119 GNUNET_YES, GNUNET_YES,
3121 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3122 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, 0, 0, c,
3123 GNUNET_NO, GNUNET_YES,
3125 c->destroy = GNUNET_YES;
3126 c->state = CADET_CONNECTION_DESTROYED;
3131 * @brief Start a polling timer for the connection.
3133 * When a neighbor does not accept more traffic on the connection it could be
3134 * caused by a simple congestion or by a lost ACK. Polling enables to check
3135 * for the lastest ACK status for a connection.
3137 * @param c Connection.
3138 * @param fwd Should we poll in the FWD direction?
3141 GCC_start_poll (struct CadetConnection *c, int fwd)
3143 struct CadetFlowControl *fc;
3145 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3146 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL %s requested\n",
3148 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task || NULL != fc->poll_msg)
3150 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** not needed (%u, %p)\n",
3151 fc->poll_task, fc->poll_msg);
3154 LOG (GNUNET_ERROR_TYPE_DEBUG, " *** POLL started on request\n");
3155 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
3162 * @brief Stop polling a connection for ACKs.
3164 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3166 * @param c Connection.
3167 * @param fwd Should we stop the poll in the FWD direction?
3170 GCC_stop_poll (struct CadetConnection *c, int fwd)
3172 struct CadetFlowControl *fc;
3174 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3175 if (GNUNET_SCHEDULER_NO_TASK != fc->poll_task)
3177 GNUNET_SCHEDULER_cancel (fc->poll_task);
3178 fc->poll_task = GNUNET_SCHEDULER_NO_TASK;
3183 * Get a (static) string for a connection.
3185 * @param c Connection.
3188 GCC_2s (const struct CadetConnection *c)
3195 static char buf[128];
3197 SPRINTF (buf, "%s (->%s)",
3198 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3201 return GNUNET_h2s (GC_h2hc (&c->id));
3206 * Log all possible info about the connection state.
3208 * @param c Connection to debug.
3209 * @param level Debug level to use.
3212 GCC_debug (const struct CadetConnection *c, enum GNUNET_ErrorType level)
3217 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
3219 __FILE__, __FUNCTION__, __LINE__);
3225 LOG2 (level, "CCC DEBUG NULL CONNECTION\n");
3229 LOG2 (level, "CCC DEBUG CONNECTION %s\n", GCC_2s (c));
3230 s = path_2s (c->path);
3231 LOG2 (level, "CCC path %s, own pos: %u\n", s, c->own_pos);
3233 LOG2 (level, "CCC state: %s, destroy: %u\n",
3234 GCC_state2s (c->state), c->destroy);
3235 LOG2 (level, "CCC pending messages: %u\n", c->pending_messages);
3236 if (NULL != c->perf)
3237 LOG2 (level, "CCC us/byte: %f\n", c->perf->avg);
3239 LOG2 (level, "CCC FWD flow control:\n");
3240 LOG2 (level, "CCC queue: %u/%u\n", c->fwd_fc.queue_n, c->fwd_fc.queue_max);
3241 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3242 c->fwd_fc.last_pid_sent, c->fwd_fc.last_pid_recv);
3243 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3244 c->fwd_fc.last_ack_sent, c->fwd_fc.last_ack_recv);
3245 LOG2 (level, "CCC POLL: task %d, msg %p, msg_ack %p)\n",
3246 c->fwd_fc.poll_task, c->fwd_fc.poll_msg, c->fwd_fc.ack_msg);
3248 LOG2 (level, "CCC BCK flow control:\n");
3249 LOG2 (level, "CCC queue: %u/%u\n", c->bck_fc.queue_n, c->bck_fc.queue_max);
3250 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3251 c->bck_fc.last_pid_sent, c->bck_fc.last_pid_recv);
3252 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3253 c->bck_fc.last_ack_sent, c->bck_fc.last_ack_recv);
3254 LOG2 (level, "CCC POLL: task %d, msg %p, msg_ack %p)\n",
3255 c->bck_fc.poll_task, c->bck_fc.poll_msg, c->bck_fc.ack_msg);
3257 LOG2 (level, "CCC DEBUG CONNECTION END\n");