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21 * @file cadet/gnunet-service-cadet_connection.c
22 * @brief GNUnet CADET service connection handling
23 * @author Bartlomiej Polot
26 #include "gnunet_util_lib.h"
27 #include "gnunet_statistics_service.h"
28 #include "cadet_path.h"
29 #include "cadet_protocol.h"
31 #include "gnunet-service-cadet_connection.h"
32 #include "gnunet-service-cadet_peer.h"
33 #include "gnunet-service-cadet_tunnel.h"
37 * Should we run somewhat expensive checks on our invariants?
39 #define CHECK_INVARIANTS 0
42 #define LOG(level, ...) GNUNET_log_from (level,"cadet-con",__VA_ARGS__)
43 #define LOG2(level, ...) GNUNET_log_from_nocheck(level,"cadet-con",__VA_ARGS__)
46 #define CADET_MAX_POLL_TIME GNUNET_TIME_relative_multiply (\
47 GNUNET_TIME_UNIT_MINUTES,\
52 /******************************************************************************/
53 /******************************** STRUCTS **********************************/
54 /******************************************************************************/
57 * Struct to encapsulate all the Flow Control information to a peer to which
58 * we are directly connected (on a core level).
60 struct CadetFlowControl
63 * Connection this controls.
65 struct CadetConnection *c;
68 * How many messages are in the queue on this connection.
73 * How many messages do we accept in the queue.
74 * If 0, the connection is broken in this direction (next hop disconnected).
76 unsigned int queue_max;
79 * ID of the last packet sent towards the peer.
81 uint32_t last_pid_sent;
84 * ID of the last packet received from the peer.
86 uint32_t last_pid_recv;
89 * Bitmap of past 32 messages received:
90 * - LSB being @c last_pid_recv.
91 * - MSB being @c last_pid_recv - 31 (mod UINTMAX).
96 * Last ACK sent to the peer (peer can't send more than this PID).
98 uint32_t last_ack_sent;
101 * Last ACK sent towards the origin (for traffic towards leaf node).
103 uint32_t last_ack_recv;
106 * Task to poll the peer in case of a lost ACK causes stall.
108 struct GNUNET_SCHEDULER_Task *poll_task;
111 * How frequently to poll for ACKs.
113 struct GNUNET_TIME_Relative poll_time;
116 * Queued poll message, to cancel if not necessary anymore (got ACK).
118 struct CadetConnectionQueue *poll_msg;
121 * Queued poll message, to cancel if not necessary anymore (got ACK).
123 struct CadetConnectionQueue *ack_msg;
127 * Keep a record of the last messages sent on this connection.
129 struct CadetConnectionPerformance
132 * Circular buffer for storing measurements.
134 double usecsperbyte[AVG_MSGS];
137 * Running average of @c usecsperbyte.
142 * How many values of @c usecsperbyte are valid.
147 * Index of the next "free" position in @c usecsperbyte.
154 * Struct containing all information regarding a connection to a peer.
156 struct CadetConnection
159 * Tunnel this connection is part of.
161 struct CadetTunnel *t;
164 * Flow control information for traffic fwd.
166 struct CadetFlowControl fwd_fc;
169 * Flow control information for traffic bck.
171 struct CadetFlowControl bck_fc;
174 * Measure connection performance on the endpoint.
176 struct CadetConnectionPerformance *perf;
179 * ID of the connection.
181 struct GNUNET_CADET_Hash id;
184 * Path being used for the tunnel. At the origin of the connection
185 * it's a pointer to the destination's path pool, otherwise just a copy.
187 struct CadetPeerPath *path;
190 * Task to keep the used paths alive at the owner,
191 * time tunnel out on all the other peers.
193 struct GNUNET_SCHEDULER_Task *fwd_maintenance_task;
196 * Task to keep the used paths alive at the destination,
197 * time tunnel out on all the other peers.
199 struct GNUNET_SCHEDULER_Task *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 * Should equal #get_next_hop(), or NULL if that peer disconnected.
210 struct CadetPeer *next_peer;
213 * Should equal #get_prev_hop(), or NULL if that peer disconnected.
215 struct CadetPeer *prev_peer;
218 * State of the connection.
220 enum CadetConnectionState state;
223 * Position of the local peer in the path.
225 unsigned int own_pos;
228 * Pending message count.
230 unsigned int pending_messages;
234 * - if 0, connection in use.
235 * - if 1, destroy on last message.
236 * - if 2, connection is being destroyed don't re-enter.
241 * In-connection-map flag. Sometimes, when @e destroy is set but
242 * actual destruction is delayed to enable us to finish processing
243 * queues (i.e. in the direction that is still working), we remove
244 * the connection from the map to prevent it from still being
245 * found (and used) by accident. This flag is set to #GNUNET_YES
246 * for a connection that is not in the #connections map. Should
247 * only be #GNUNET_YES if #destroy is also non-zero.
252 * Counter to do exponential backoff when creating a connection (max 64).
254 unsigned short create_retry;
257 * Task to check if connection has duplicates.
259 struct GNUNET_SCHEDULER_Task *check_duplicates_task;
264 * Handle for messages queued but not yet sent.
266 struct CadetConnectionQueue
269 * Peer queue handle, to cancel if necessary.
271 struct CadetPeerQueue *q;
274 * Continuation to call once sent.
279 * Closure for @e cont.
284 * Was this a forced message? (Do not account for it)
289 /******************************************************************************/
290 /******************************* GLOBALS ***********************************/
291 /******************************************************************************/
294 * Global handle to the statistics service.
296 extern struct GNUNET_STATISTICS_Handle *stats;
299 * Local peer own ID (memory efficient handle).
301 extern GNUNET_PEER_Id myid;
304 * Local peer own ID (full value).
306 extern struct GNUNET_PeerIdentity my_full_id;
309 * Connections known, indexed by cid (CadetConnection).
311 static struct GNUNET_CONTAINER_MultiHashMap *connections;
314 * How many connections are we willing to maintain.
315 * Local connections are always allowed, even if there are more connections than max.
317 static unsigned long long max_connections;
320 * How many messages *in total* are we willing to queue, divide by number of
321 * connections to get connection queue size.
323 static unsigned long long max_msgs_queue;
326 * How often to send path keepalives. Paths timeout after 4 missed.
328 static struct GNUNET_TIME_Relative refresh_connection_time;
331 * How often to send path create / ACKs.
333 static struct GNUNET_TIME_Relative create_connection_time;
336 /******************************************************************************/
337 /******************************** STATIC ***********************************/
338 /******************************************************************************/
342 #if 0 // avoid compiler warning for unused static function
344 fc_debug (struct CadetFlowControl *fc)
346 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
347 fc->last_pid_recv, fc->last_ack_sent);
348 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
349 fc->last_pid_sent, fc->last_ack_recv);
350 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
351 fc->queue_n, fc->queue_max);
355 connection_debug (struct CadetConnection *c)
359 LOG (GNUNET_ERROR_TYPE_INFO, "DEBUG NULL CONNECTION\n");
362 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
363 peer2s (c->t->peer), GCC_2s (c));
364 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
365 c->state, c->pending_messages);
366 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
367 fc_debug (&c->fwd_fc);
368 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
369 fc_debug (&c->bck_fc);
375 * Schedule next keepalive task, taking in consideration
376 * the connection state and number of retries.
378 * @param c Connection for which to schedule the next keepalive.
379 * @param fwd Direction for the next keepalive.
382 schedule_next_keepalive (struct CadetConnection *c, int fwd);
386 * Resets the connection timeout task, some other message has done the
388 * - For the first peer on the direction this means to send
389 * a keepalive or a path confirmation message (either create or ACK).
390 * - For all other peers, this means to destroy the connection,
391 * due to lack of activity.
392 * Starts the timeout if no timeout was running (connection just created).
394 * @param c Connection whose timeout to reset.
395 * @param fwd Is this forward?
398 connection_reset_timeout (struct CadetConnection *c, int fwd);
402 * Get string description for tunnel state. Reentrant.
404 * @param s Tunnel state.
406 * @return String representation.
409 GCC_state2s (enum CadetConnectionState s)
413 case CADET_CONNECTION_NEW:
414 return "CADET_CONNECTION_NEW";
415 case CADET_CONNECTION_SENT:
416 return "CADET_CONNECTION_SENT";
417 case CADET_CONNECTION_ACK:
418 return "CADET_CONNECTION_ACK";
419 case CADET_CONNECTION_READY:
420 return "CADET_CONNECTION_READY";
421 case CADET_CONNECTION_DESTROYED:
422 return "CADET_CONNECTION_DESTROYED";
423 case CADET_CONNECTION_BROKEN:
424 return "CADET_CONNECTION_BROKEN";
427 LOG (GNUNET_ERROR_TYPE_ERROR, " conn state %u unknown!\n", s);
428 return "CADET_CONNECTION_STATE_ERROR";
434 * Initialize a Flow Control structure to the initial state.
436 * @param fc Flow Control structure to initialize.
439 fc_init (struct CadetFlowControl *fc)
441 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
442 fc->last_pid_recv = (uint32_t) -1;
443 fc->last_ack_sent = (uint32_t) 0;
444 fc->last_ack_recv = (uint32_t) 0;
445 fc->poll_task = NULL;
446 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
448 fc->queue_max = (max_msgs_queue / max_connections) + 1;
455 * @param cid Connection ID.
457 * @return conntection with the given ID @cid or NULL if not found.
459 static struct CadetConnection *
460 connection_get (const struct GNUNET_CADET_Hash *cid)
462 return GNUNET_CONTAINER_multihashmap_get (connections, GC_h2hc (cid));
467 * Change the connection state. Cannot change a connection marked as destroyed.
469 * @param c Connection to change.
470 * @param state New state to set.
473 connection_change_state (struct CadetConnection* c,
474 enum CadetConnectionState state)
476 LOG (GNUNET_ERROR_TYPE_DEBUG,
477 "Connection %s state %s -> %s\n",
478 GCC_2s (c), GCC_state2s (c->state), GCC_state2s (state));
479 if (CADET_CONNECTION_DESTROYED <= c->state) /* Destroyed or broken. */
481 LOG (GNUNET_ERROR_TYPE_DEBUG, "state not changing anymore\n");
485 if (CADET_CONNECTION_READY == state)
491 * Mark a connection as "destroyed", to send all pending traffic and freeing
492 * all associated resources, without accepting new status changes on it.
494 * @param c Connection to mark as destroyed.
497 mark_destroyed (struct CadetConnection *c)
499 c->destroy = GNUNET_YES;
500 connection_change_state (c, CADET_CONNECTION_DESTROYED);
505 * Callback called when a queued ACK message is sent.
507 * @param cls Closure (FC).
508 * @param c Connection this message was on.
509 * @param q Queue handler this call invalidates.
510 * @param type Type of message sent.
511 * @param fwd Was this a FWD going message?
512 * @param size Size of the message.
516 struct CadetConnection *c,
517 struct CadetConnectionQueue *q,
518 uint16_t type, int fwd, size_t size)
520 struct CadetFlowControl *fc = cls;
527 * Send an ACK on the connection, informing the predecessor about
528 * the available buffer space. Should not be called in case the peer
529 * is origin (no predecessor) in the @c fwd direction.
531 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
532 * the ACK itself goes "back" (dest->root).
534 * @param c Connection on which to send the ACK.
535 * @param buffer How much space free to advertise?
536 * @param fwd Is this FWD ACK? (Going dest -> root)
537 * @param force Don't optimize out.
540 send_ack (struct CadetConnection *c, unsigned int buffer, int fwd, int force)
542 struct CadetFlowControl *next_fc;
543 struct CadetFlowControl *prev_fc;
544 struct GNUNET_CADET_ACK msg;
548 /* If origin, there is no connection to send ACKs. Wrong function! */
549 GCC_check_connections ();
550 if (GCC_is_origin (c, fwd))
552 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection %s is origin in %s\n",
553 GCC_2s (c), GC_f2s (fwd));
558 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
559 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
561 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection send %s ack on %s\n",
562 GC_f2s (fwd), GCC_2s (c));
564 /* Check if we need to transmit the ACK. */
565 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
566 if (3 < delta && buffer < delta && GNUNET_NO == force)
568 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
569 LOG (GNUNET_ERROR_TYPE_DEBUG,
570 " last pid recv: %u, last ack sent: %u\n",
571 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
572 GCC_check_connections ();
576 /* Ok, ACK might be necessary, what PID to ACK? */
577 ack = prev_fc->last_pid_recv + buffer;
578 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
579 LOG (GNUNET_ERROR_TYPE_DEBUG,
580 " last pid %u, last ack %u, qmax %u, q %u\n",
581 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
582 next_fc->queue_max, next_fc->queue_n);
583 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
585 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
586 GCC_check_connections ();
590 /* Check if message is already in queue */
591 if (NULL != prev_fc->ack_msg)
593 if (GC_is_pid_bigger (ack, prev_fc->last_ack_sent))
595 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
596 GCC_cancel (prev_fc->ack_msg);
597 /* GCC_cancel triggers ack_sent(), which clears fc->ack_msg */
601 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
602 GCC_check_connections ();
607 prev_fc->last_ack_sent = ack;
609 /* Build ACK message and send on conn */
610 msg.header.size = htons (sizeof (msg));
611 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_ACK);
612 msg.ack = htonl (ack);
615 prev_fc->ack_msg = GCC_send_prebuilt_message (&msg.header, UINT16_MAX, ack,
618 GNUNET_assert (NULL != prev_fc->ack_msg);
619 GCC_check_connections ();
624 * Callback called when a connection queued message is sent.
626 * Calculates the average time and connection packet tracking.
628 * @param cls Closure (ConnectionQueue Handle).
629 * @param c Connection this message was on.
630 * @param sent Was it really sent? (Could have been canceled)
631 * @param type Type of message sent.
632 * @param pid Packet ID, or 0 if not applicable (create, destroy, etc).
633 * @param fwd Was this a FWD going message?
634 * @param size Size of the message.
635 * @param wait Time spent waiting for core (only the time for THIS message)
636 * @return #GNUNET_YES if connection was destroyed, #GNUNET_NO otherwise.
639 conn_message_sent (void *cls,
640 struct CadetConnection *c, int sent,
641 uint16_t type, uint32_t pid, int fwd, size_t size,
642 struct GNUNET_TIME_Relative wait)
644 struct CadetConnectionPerformance *p;
645 struct CadetFlowControl *fc;
646 struct CadetConnectionQueue *q = cls;
650 GCC_check_connections ();
651 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection message_sent\n");
653 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
655 fc = fwd ? &c->fwd_fc : &c->bck_fc;
656 LOG (GNUNET_ERROR_TYPE_DEBUG, " %ssent %s %s pid %u\n",
657 sent ? "" : "not ", GC_f2s (fwd), GC_m2s (type), pid);
663 LOG (GNUNET_ERROR_TYPE_DEBUG, " calling cont\n");
664 q->cont (q->cont_cls, c, q, type, fwd, size);
668 else if (type == GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED
669 || type == GNUNET_MESSAGE_TYPE_CADET_AX)
671 /* If NULL == q and ENCRYPTED == type, message must have been ch_mngmnt */
680 if (type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN
681 && type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY)
683 LOG (GNUNET_ERROR_TYPE_ERROR, "Message %s sent on NULL connection!\n",
686 GCC_check_connections ();
689 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P- %p %u\n", c, c->pending_messages);
690 c->pending_messages--;
691 if ( (GNUNET_YES == c->destroy) &&
692 (0 == c->pending_messages) )
694 LOG (GNUNET_ERROR_TYPE_DEBUG,
695 "! destroying connection!\n");
697 GCC_check_connections ();
700 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
703 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
704 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
705 c->maintenance_q = NULL;
706 /* Don't trigger a keepalive for sent ACKs, only SYN and SYNACKs */
707 if (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE == type || !fwd)
708 schedule_next_keepalive (c, fwd);
711 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
712 case GNUNET_MESSAGE_TYPE_CADET_AX:
713 if (GNUNET_YES == sent)
715 GNUNET_assert (NULL != q);
716 fc->last_pid_sent = pid;
717 if (GC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
718 GCC_start_poll (c, fwd);
719 GCC_send_ack (c, fwd, GNUNET_NO);
720 connection_reset_timeout (c, fwd);
723 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
724 if (GNUNET_NO == forced)
727 LOG (GNUNET_ERROR_TYPE_DEBUG,
728 "! accounting pid %u\n",
733 LOG (GNUNET_ERROR_TYPE_DEBUG,
734 "! forced, Q_N not accounting pid %u\n",
739 case GNUNET_MESSAGE_TYPE_CADET_KX:
740 if (GNUNET_YES == sent)
741 connection_reset_timeout (c, fwd);
744 case GNUNET_MESSAGE_TYPE_CADET_POLL:
748 case GNUNET_MESSAGE_TYPE_CADET_ACK:
752 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
753 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
757 LOG (GNUNET_ERROR_TYPE_ERROR, "%s unknown\n", GC_m2s (type));
761 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
764 return GNUNET_NO; /* Only endpoints are interested in timing. */
767 usecsperbyte = ((double) wait.rel_value_us) / size;
768 if (p->size == AVG_MSGS)
770 /* Array is full. Substract oldest value, add new one and store. */
771 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
772 p->usecsperbyte[p->idx] = usecsperbyte;
773 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
777 /* Array not yet full. Add current value to avg and store. */
778 p->usecsperbyte[p->idx] = usecsperbyte;
780 p->avg += p->usecsperbyte[p->idx];
784 p->idx = (p->idx + 1) % AVG_MSGS;
785 GCC_check_connections ();
791 * Get the previous hop in a connection
793 * @param c Connection.
795 * @return Previous peer in the connection.
797 static struct CadetPeer *
798 get_prev_hop (const struct CadetConnection *c)
804 LOG (GNUNET_ERROR_TYPE_DEBUG,
805 " get prev hop %s [%u/%u]\n",
806 GCC_2s (c), c->own_pos, c->path->length);
807 if (0 == c->own_pos || c->path->length < 2)
808 id = c->path->peers[0];
810 id = c->path->peers[c->own_pos - 1];
812 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
813 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
815 return GCP_get_short (id, GNUNET_YES);
820 * Get the next hop in a connection
822 * @param c Connection.
824 * @return Next peer in the connection.
826 static struct CadetPeer *
827 get_next_hop (const struct CadetConnection *c)
834 LOG (GNUNET_ERROR_TYPE_DEBUG, " get next hop %s [%u/%u]\n",
835 GCC_2s (c), c->own_pos, c->path->length);
836 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
837 id = c->path->peers[c->path->length - 1];
839 id = c->path->peers[c->own_pos + 1];
841 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
842 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
844 return GCP_get_short (id, GNUNET_YES);
849 * Check that the direct neighbours (previous and next hop)
850 * are properly associated with this connection.
852 * @param c connection to check
855 check_neighbours (const struct CadetConnection *c)
858 return; /* nothing to check */
859 GCP_check_connection (get_next_hop (c), c);
860 GCP_check_connection (get_prev_hop (c), c);
865 * Helper for #GCC_check_connections(). Calls #check_neighbours().
869 * @param value the `struct CadetConnection` to check
870 * @return #GNUNET_OK (continue to iterate)
873 check_connection (void *cls,
874 const struct GNUNET_HashCode *key,
877 struct CadetConnection *c = value;
879 check_neighbours (c);
885 * Check invariants for all connections using #check_neighbours().
888 GCC_check_connections ()
890 if (0 == CHECK_INVARIANTS)
892 if (NULL == connections)
894 GNUNET_CONTAINER_multihashmap_iterate (connections,
901 * Get the hop in a connection.
903 * @param c Connection.
904 * @param fwd Next in the FWD direction?
906 * @return Next peer in the connection.
908 static struct CadetPeer *
909 get_hop (struct CadetConnection *c, int fwd)
911 return (fwd) ? get_next_hop (c) : get_prev_hop (c);
916 * Get a bit mask for a message received out-of-order.
918 * @param last_pid_recv Last PID we received prior to the out-of-order.
919 * @param ooo_pid PID of the out-of-order message.
922 get_recv_bitmask (uint32_t last_pid_recv, uint32_t ooo_pid)
924 return 1 << (last_pid_recv - ooo_pid);
929 * Check is an out-of-order message is ok:
930 * - at most 31 messages behind.
933 * @param last_pid_recv Last in-order PID received.
936 is_ooo_ok (uint32_t last_pid_recv, uint32_t ooo_pid, uint32_t ooo_bitmap)
940 if (GC_is_pid_bigger (last_pid_recv - 31, ooo_pid))
943 mask = get_recv_bitmask (last_pid_recv, ooo_pid);
944 if (0 != (ooo_bitmap & mask))
952 * Is traffic coming from this sender 'FWD' traffic?
954 * @param c Connection to check.
955 * @param sender Peer identity of neighbor.
957 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
958 * the traffic is 'FWD'.
959 * #GNUNET_NO for BCK.
960 * #GNUNET_SYSERR for errors.
963 is_fwd (const struct CadetConnection *c,
964 const struct GNUNET_PeerIdentity *sender)
968 id = GNUNET_PEER_search (sender);
969 if (GCP_get_short_id (get_prev_hop (c)) == id)
972 if (GCP_get_short_id (get_next_hop (c)) == id)
976 return GNUNET_SYSERR;
981 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
982 * or a first CONNECTION_ACK directed to us.
984 * @param connection Connection to confirm.
985 * @param fwd Should we send it FWD? (root->dest)
986 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
989 send_connection_ack (struct CadetConnection *connection, int fwd)
991 struct CadetTunnel *t;
992 size_t size = sizeof (struct GNUNET_CADET_ConnectionACK);
994 GCC_check_connections ();
996 LOG (GNUNET_ERROR_TYPE_INFO,
997 "==> { C %s ACK} %19s on conn %s (%p) %s [%5u]\n",
998 GC_f2s (!fwd), "", GCC_2s (connection), connection, GC_f2s (fwd), size);
999 GCP_queue_add (get_hop (connection, fwd), NULL,
1000 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK, UINT16_MAX, 0,
1001 size, connection, fwd, &conn_message_sent, NULL);
1002 connection->pending_messages++;
1003 if (CADET_TUNNEL_NEW == GCT_get_cstate (t))
1004 GCT_change_cstate (t, CADET_TUNNEL_WAITING);
1005 if (CADET_CONNECTION_READY != connection->state)
1006 connection_change_state (connection, CADET_CONNECTION_SENT);
1007 GCC_check_connections ();
1012 * Send a notification that a connection is broken.
1014 * @param c Connection that is broken.
1015 * @param id1 Peer that has disconnected.
1016 * @param id2 Peer that has disconnected.
1017 * @param fwd Direction towards which to send it.
1020 send_broken (struct CadetConnection *c,
1021 const struct GNUNET_PeerIdentity *id1,
1022 const struct GNUNET_PeerIdentity *id2,
1025 struct GNUNET_CADET_ConnectionBroken msg;
1027 GCC_check_connections ();
1028 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1029 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1033 GNUNET_assert (NULL ==
1034 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, 0, c, fwd,
1035 GNUNET_YES, NULL, NULL));
1036 GCC_check_connections ();
1041 * Send a notification that a connection is broken, when a connection
1042 * isn't even known to the local peer or soon to be destroyed.
1044 * @param connection_id Connection ID.
1045 * @param id1 Peer that has disconnected, probably local peer.
1046 * @param id2 Peer that has disconnected can be NULL if unknown.
1047 * @param peer Peer to notify (neighbor who sent the connection).
1050 send_broken_unknown (const struct GNUNET_CADET_Hash *connection_id,
1051 const struct GNUNET_PeerIdentity *id1,
1052 const struct GNUNET_PeerIdentity *id2,
1053 const struct GNUNET_PeerIdentity *peer_id)
1055 struct GNUNET_CADET_ConnectionBroken *msg;
1056 struct CadetPeerQueue *q;
1057 struct CadetPeer *neighbor;
1059 GCC_check_connections ();
1060 LOG (GNUNET_ERROR_TYPE_INFO, "--> BROKEN on unknown connection %s\n",
1061 GNUNET_h2s (GC_h2hc (connection_id)));
1063 msg = GNUNET_new (struct GNUNET_CADET_ConnectionBroken);
1064 msg->header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1065 msg->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1066 msg->cid = *connection_id;
1071 memset (&msg->peer2, 0, sizeof (msg->peer2));
1072 neighbor = GCP_get (peer_id, GNUNET_NO); /* We MUST know neighbor. */
1073 GNUNET_assert (NULL != neighbor);
1074 q = GCP_queue_add (neighbor, msg, GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN,
1076 sizeof (struct GNUNET_CADET_ConnectionBroken),
1077 NULL, GNUNET_SYSERR, /* connection, fwd */
1078 NULL, NULL); /* continuation */
1079 GNUNET_assert (NULL != q);
1080 GCC_check_connections ();
1085 * Send keepalive packets for a connection.
1087 * @param c Connection to keep alive..
1088 * @param fwd Is this a FWD keepalive? (owner -> dest).
1091 send_connection_keepalive (struct CadetConnection *c, int fwd)
1093 struct GNUNET_MessageHeader msg;
1094 struct CadetFlowControl *fc;
1096 GCC_check_connections ();
1097 LOG (GNUNET_ERROR_TYPE_INFO,
1098 "keepalive %s for connection %s\n",
1099 GC_f2s (fwd), GCC_2s (c));
1101 GNUNET_assert (NULL != c->t);
1102 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1103 if (0 < fc->queue_n || GNUNET_YES == GCT_has_queued_traffic (c->t))
1105 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, traffic in queue\n");
1109 GNUNET_STATISTICS_update (stats, "# keepalives sent", 1, GNUNET_NO);
1111 GNUNET_assert (NULL != c->t);
1112 msg.size = htons (sizeof (msg));
1113 msg.type = htons (GNUNET_MESSAGE_TYPE_CADET_KEEPALIVE);
1115 GNUNET_assert (NULL ==
1116 GCT_send_prebuilt_message (&msg, c->t, c,
1117 GNUNET_NO, NULL, NULL));
1118 GCC_check_connections ();
1123 * Send CONNECTION_{CREATE/ACK} packets for a connection.
1125 * @param c Connection for which to send the message.
1126 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
1129 connection_recreate (struct CadetConnection *c, int fwd)
1131 LOG (GNUNET_ERROR_TYPE_DEBUG,
1132 "sending connection recreate\n");
1134 GCC_send_create (c);
1136 send_connection_ack (c, GNUNET_NO);
1141 * Generic connection timer management.
1142 * Depending on the role of the peer in the connection will send the
1143 * appropriate message (build or keepalive)
1145 * @param c Conncetion to maintain.
1146 * @param fwd Is FWD?
1149 connection_maintain (struct CadetConnection *c, int fwd)
1151 if (GNUNET_NO != c->destroy)
1153 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, being destroyed\n");
1160 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1164 if (CADET_TUNNEL_SEARCHING == GCT_get_cstate (c->t))
1166 /* If status is SEARCHING, why is there a connection? Should be WAITING */
1168 GCT_debug (c->t, GNUNET_ERROR_TYPE_ERROR);
1169 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, tunnel SEARCHING\n");
1170 schedule_next_keepalive (c, fwd);
1175 case CADET_CONNECTION_NEW:
1178 case CADET_CONNECTION_SENT:
1179 connection_recreate (c, fwd);
1181 case CADET_CONNECTION_READY:
1182 send_connection_keepalive (c, fwd);
1191 * Keep the connection alive.
1193 * @param c Connection to keep alive.
1194 * @param fwd Direction.
1197 connection_keepalive (struct CadetConnection *c,
1200 GCC_check_connections ();
1201 LOG (GNUNET_ERROR_TYPE_DEBUG,
1202 "%s keepalive for %s\n",
1203 GC_f2s (fwd), GCC_2s (c));
1206 c->fwd_maintenance_task = NULL;
1208 c->bck_maintenance_task = NULL;
1209 connection_maintain (c, fwd);
1210 GCC_check_connections ();
1211 /* Next execution will be scheduled by message_sent or _maintain*/
1216 * Keep the connection alive in the FWD direction.
1218 * @param cls Closure (connection to keepalive).
1221 connection_fwd_keepalive (void *cls)
1223 struct CadetConnection *c = cls;
1225 GCC_check_connections ();
1226 connection_keepalive (c,
1228 GCC_check_connections ();
1233 * Keep the connection alive in the BCK direction.
1235 * @param cls Closure (connection to keepalive).
1238 connection_bck_keepalive (void *cls)
1240 struct CadetConnection *c = cls;
1242 GCC_check_connections ();
1243 connection_keepalive (c,
1245 GCC_check_connections ();
1250 * Schedule next keepalive task, taking in consideration
1251 * the connection state and number of retries.
1253 * If the peer is not the origin, do nothing.
1255 * @param c Connection for which to schedule the next keepalive.
1256 * @param fwd Direction for the next keepalive.
1259 schedule_next_keepalive (struct CadetConnection *c, int fwd)
1261 struct GNUNET_TIME_Relative delay;
1262 struct GNUNET_SCHEDULER_Task * *task_id;
1263 GNUNET_SCHEDULER_TaskCallback keepalive_task;
1265 GCC_check_connections ();
1266 if (GNUNET_NO == GCC_is_origin (c, fwd))
1269 /* Calculate delay to use, depending on the state of the connection */
1270 if (CADET_CONNECTION_READY == c->state)
1272 delay = refresh_connection_time;
1276 if (1 > c->create_retry)
1277 c->create_retry = 1;
1278 delay = GNUNET_TIME_relative_multiply (create_connection_time,
1280 if (c->create_retry < 64)
1281 c->create_retry *= 2;
1284 /* Select direction-dependent parameters */
1285 if (GNUNET_YES == fwd)
1287 task_id = &c->fwd_maintenance_task;
1288 keepalive_task = &connection_fwd_keepalive;
1292 task_id = &c->bck_maintenance_task;
1293 keepalive_task = &connection_bck_keepalive;
1296 /* Check that no one scheduled it before us */
1297 if (NULL != *task_id)
1299 /* No need for a _break. It can happen for instance when sending a SYNACK
1300 * for a duplicate SYN: the first SYNACK scheduled the task. */
1301 GNUNET_SCHEDULER_cancel (*task_id);
1304 /* Schedule the task */
1305 *task_id = GNUNET_SCHEDULER_add_delayed (delay,
1308 LOG (GNUNET_ERROR_TYPE_DEBUG,
1309 "next keepalive in %s\n",
1310 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1311 GCC_check_connections ();
1316 * @brief Re-initiate traffic on this connection if necessary.
1318 * Check if there is traffic queued towards this peer
1319 * and the core transmit handle is NULL (traffic was stalled).
1320 * If so, call core tmt rdy.
1322 * @param c Connection on which initiate traffic.
1323 * @param fwd Is this about fwd traffic?
1326 connection_unlock_queue (struct CadetConnection *c, int fwd)
1328 struct CadetPeer *peer;
1330 GCC_check_connections ();
1331 LOG (GNUNET_ERROR_TYPE_DEBUG,
1332 "connection_unlock_queue %s on %s\n",
1333 GC_f2s (fwd), GCC_2s (c));
1335 if (GCC_is_terminal (c, fwd))
1337 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal, can unlock!\n");
1341 peer = get_hop (c, fwd);
1342 GCP_queue_unlock (peer, c);
1343 GCC_check_connections ();
1348 * Cancel all transmissions that belong to a certain connection.
1350 * If the connection is scheduled for destruction and no more messages are left,
1351 * the connection will be destroyed by the continuation call.
1353 * @param c Connection which to cancel. Might be destroyed during this call.
1354 * @param fwd Cancel fwd traffic?
1357 connection_cancel_queues (struct CadetConnection *c,
1360 struct CadetFlowControl *fc;
1361 struct CadetPeer *peer;
1363 GCC_check_connections ();
1364 LOG (GNUNET_ERROR_TYPE_DEBUG,
1365 "Cancel %s queues for connection %s\n",
1366 GC_f2s (fwd), GCC_2s (c));
1373 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1374 if (NULL != fc->poll_task)
1376 GNUNET_SCHEDULER_cancel (fc->poll_task);
1377 fc->poll_task = NULL;
1378 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL task for fc %p\n", fc);
1380 if (NULL != fc->poll_msg)
1382 GCC_cancel (fc->poll_msg);
1383 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL msg for fc %p\n", fc);
1385 peer = get_hop (c, fwd);
1386 GCP_queue_cancel (peer, c);
1387 GCC_check_connections ();
1392 * Function called if a connection has been stalled for a while,
1393 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1395 * @param cls Closure (poll ctx).
1398 connection_poll (void *cls);
1402 * Callback called when a queued POLL message is sent.
1404 * @param cls Closure (flow control context).
1405 * @param c Connection this message was on.
1406 * @param q Queue handler this call invalidates.
1407 * @param type Type of message sent.
1408 * @param fwd Was this a FWD going message?
1409 * @param size Size of the message.
1412 poll_sent (void *cls,
1413 struct CadetConnection *c,
1414 struct CadetConnectionQueue *q,
1415 uint16_t type, int fwd, size_t size)
1417 struct CadetFlowControl *fc = cls;
1419 GNUNET_assert (fc->poll_msg == q);
1420 fc->poll_msg = NULL;
1421 if (2 == c->destroy)
1423 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL canceled on shutdown\n");
1426 if (0 == fc->queue_max)
1428 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL cancelled: neighbor disconnected\n");
1431 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL sent for %s, scheduling new one!\n",
1433 GNUNET_assert (NULL == fc->poll_task);
1434 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1435 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1438 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1443 * Function called if a connection has been stalled for a while,
1444 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1446 * @param cls Closure (poll ctx).
1449 connection_poll (void *cls)
1451 struct CadetFlowControl *fc = cls;
1452 struct GNUNET_CADET_Poll msg;
1453 struct CadetConnection *c;
1456 fc->poll_task = NULL;
1457 GCC_check_connections ();
1459 fwd = fc == &c->fwd_fc;
1460 LOG (GNUNET_ERROR_TYPE_DEBUG, "Polling connection %s %s\n",
1461 GCC_2s (c), GC_f2s (fwd));
1463 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_POLL);
1464 msg.header.size = htons (sizeof (msg));
1465 msg.pid = htonl (fc->last_pid_sent);
1466 LOG (GNUNET_ERROR_TYPE_DEBUG, " last pid sent: %u\n", fc->last_pid_sent);
1468 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, fc->last_pid_sent, c,
1469 fc == &c->fwd_fc, GNUNET_YES, &poll_sent, fc);
1470 GNUNET_assert (NULL != fc->poll_msg);
1471 GCC_check_connections ();
1476 * Resend all queued messages for a connection on other connections of the
1477 * same tunnel, if possible. The connection WILL BE DESTROYED by this function.
1479 * @param c Connection whose messages to resend.
1480 * @param fwd Resend fwd messages?
1483 resend_messages_and_destroy (struct CadetConnection *c, int fwd)
1485 struct GNUNET_MessageHeader *out_msg;
1486 struct CadetTunnel *t = c->t;
1487 struct CadetPeer *neighbor;
1488 unsigned int pending;
1491 GCC_check_connections ();
1494 destroyed = GNUNET_NO;
1495 neighbor = get_hop (c, fwd);
1496 pending = c->pending_messages;
1498 while (NULL != (out_msg = GCP_connection_pop (neighbor, c, &destroyed)))
1501 GCT_resend_message (out_msg, t);
1502 GNUNET_free (out_msg);
1505 /* All pending messages should have been popped,
1506 * and the connection destroyed by the continuation.
1508 if (GNUNET_YES != destroyed)
1513 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1514 if (NULL != t) GCT_debug (t, GNUNET_ERROR_TYPE_ERROR);
1518 GCC_check_connections ();
1523 * Generic connection timeout implementation.
1525 * Timeout function due to lack of keepalive/traffic from an endpoint.
1526 * Destroys connection if called.
1528 * @param c Connection to destroy.
1529 * @param fwd Was the timeout from the origin? (FWD timeout)
1532 connection_timeout (struct CadetConnection *c, int fwd)
1534 struct CadetFlowControl *reverse_fc;
1536 GCC_check_connections ();
1537 reverse_fc = fwd ? &c->bck_fc : &c->fwd_fc;
1539 LOG (GNUNET_ERROR_TYPE_INFO,
1540 "Connection %s %s timed out. Destroying.\n",
1543 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1545 if (GCC_is_origin (c, fwd)) /* Loopback? Something is wrong! */
1551 /* If dest, salvage queued traffic. */
1552 if (GCC_is_terminal (c, fwd))
1554 const struct GNUNET_PeerIdentity *next_hop;
1556 next_hop = GCP_get_id (fwd ? get_prev_hop (c) : get_next_hop (c));
1557 send_broken_unknown (&c->id, &my_full_id, NULL, next_hop);
1558 if (0 < reverse_fc->queue_n)
1559 resend_messages_and_destroy (c, !fwd);
1560 GCC_check_connections ();
1565 GCC_check_connections ();
1570 * Timeout function due to lack of keepalive/traffic from the owner.
1571 * Destroys connection if called.
1573 * @param cls Closure (connection to destroy).
1576 connection_fwd_timeout (void *cls)
1578 struct CadetConnection *c = cls;
1580 c->fwd_maintenance_task = NULL;
1581 GCC_check_connections ();
1582 connection_timeout (c, GNUNET_YES);
1583 GCC_check_connections ();
1588 * Timeout function due to lack of keepalive/traffic from the destination.
1589 * Destroys connection if called.
1591 * @param cls Closure (connection to destroy).
1594 connection_bck_timeout (void *cls)
1596 struct CadetConnection *c = cls;
1598 c->bck_maintenance_task = NULL;
1599 GCC_check_connections ();
1600 connection_timeout (c, GNUNET_NO);
1601 GCC_check_connections ();
1606 * Resets the connection timeout task, some other message has done the
1608 * - For the first peer on the direction this means to send
1609 * a keepalive or a path confirmation message (either create or ACK).
1610 * - For all other peers, this means to destroy the connection,
1611 * due to lack of activity.
1612 * Starts the timeout if no timeout was running (connection just created).
1614 * @param c Connection whose timeout to reset.
1615 * @param fwd Is this forward?
1617 * TODO use heap to improve efficiency of scheduler.
1620 connection_reset_timeout (struct CadetConnection *c, int fwd)
1622 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1623 if (GCC_is_origin (c, fwd)) /* Startpoint */
1625 schedule_next_keepalive (c, fwd);
1627 else /* Relay, endpoint. */
1629 struct GNUNET_TIME_Relative delay;
1630 struct GNUNET_SCHEDULER_Task * *ti;
1631 GNUNET_SCHEDULER_TaskCallback f;
1633 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1636 GNUNET_SCHEDULER_cancel (*ti);
1637 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1638 LOG (GNUNET_ERROR_TYPE_DEBUG,
1639 " timing out in %s\n",
1640 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_NO));
1641 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1642 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1648 * Iterator to compare each connection's path with the path of a new connection.
1650 * If the connection coincides, the c member of path is set to the connection
1651 * and the destroy flag of the connection is set.
1653 * @param cls Closure (new path).
1654 * @param c Connection in the tunnel to check.
1657 check_path (void *cls, struct CadetConnection *c)
1659 struct CadetConnection *new_conn = cls;
1660 struct CadetPeerPath *path = new_conn->path;
1662 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking %s (%p), length %u\n",
1663 GCC_2s (c), c, c->path->length);
1666 && GNUNET_NO == c->destroy
1667 && CADET_CONNECTION_BROKEN != c->state
1668 && CADET_CONNECTION_DESTROYED != c->state
1669 && path_equivalent (path, c->path))
1671 new_conn->destroy = GNUNET_YES; /* Do not mark_destroyed, */
1672 new_conn->path->c = c; /* this is only a flag for the Iterator. */
1673 LOG (GNUNET_ERROR_TYPE_DEBUG, " MATCH!\n");
1679 * Finds out if this path is already being used by an existing connection.
1681 * Checks the tunnel towards the destination to see if it contains
1682 * any connection with the same path.
1684 * If the existing connection is ready, it is kept.
1685 * Otherwise if the sender has a smaller ID that ours, we accept it (and
1686 * the peer will eventually reject our attempt).
1688 * @param path Path to check.
1689 * @return #GNUNET_YES if the tunnel has a connection with the same path,
1690 * #GNUNET_NO otherwise.
1693 does_connection_exist (struct CadetConnection *conn)
1695 struct CadetPeer *p;
1696 struct CadetTunnel *t;
1697 struct CadetConnection *c;
1699 p = GCP_get_short (conn->path->peers[0], GNUNET_NO);
1702 t = GCP_get_tunnel (p);
1706 LOG (GNUNET_ERROR_TYPE_DEBUG, "Checking for duplicates\n");
1708 GCT_iterate_connections (t, &check_path, conn);
1710 if (GNUNET_YES == conn->destroy)
1713 conn->destroy = GNUNET_NO;
1714 conn->path->c = conn;
1715 LOG (GNUNET_ERROR_TYPE_DEBUG, " found duplicate of %s\n", GCC_2s (conn));
1716 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate: %s\n", GCC_2s (c));
1717 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1718 if (CADET_CONNECTION_READY == c->state)
1720 /* The other peer confirmed a live connection with this path,
1721 * why are they trying to duplicate it? */
1722 GNUNET_STATISTICS_update (stats, "# duplicate connections", 1, GNUNET_NO);
1725 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate not valid, connection unique\n");
1730 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s has no duplicates\n", GCC_2s (conn));
1737 * @brief Check if the tunnel this connection belongs to has any other
1738 * connection with the same path, and destroy one if so.
1740 * @param cls Closure (connection to check).
1743 check_duplicates (void *cls)
1745 struct CadetConnection *c = cls;
1747 c->check_duplicates_task = NULL;
1748 if (GNUNET_YES == does_connection_exist (c))
1750 GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1751 send_broken (c, &my_full_id, &my_full_id, GCC_is_origin (c, GNUNET_YES));
1758 * Wait for enough time to let any dead connections time out and check for
1759 * any remaining duplicates.
1761 * @param c Connection that is a potential duplicate.
1764 schedule_check_duplicates (struct CadetConnection *c)
1766 struct GNUNET_TIME_Relative delay;
1768 if (NULL != c->check_duplicates_task)
1770 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 5);
1771 c->check_duplicates_task = GNUNET_SCHEDULER_add_delayed (delay,
1778 * Add the connection to the list of both neighbors.
1780 * @param c Connection.
1782 * @return #GNUNET_OK if everything went fine
1783 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1786 register_neighbors (struct CadetConnection *c)
1788 c->next_peer = get_next_hop (c);
1789 c->prev_peer = get_prev_hop (c);
1790 GNUNET_assert (c->next_peer != c->prev_peer);
1791 LOG (GNUNET_ERROR_TYPE_DEBUG,
1792 "register neighbors for connection %s\n",
1794 path_debug (c->path);
1795 LOG (GNUNET_ERROR_TYPE_DEBUG,
1796 "own pos %u\n", c->own_pos);
1797 LOG (GNUNET_ERROR_TYPE_DEBUG,
1798 "putting connection %s to next peer %p\n",
1801 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n",
1803 GCP_2s (c->next_peer));
1804 LOG (GNUNET_ERROR_TYPE_DEBUG,
1805 "putting connection %s to prev peer %p\n",
1808 LOG (GNUNET_ERROR_TYPE_DEBUG,
1809 "prev peer %p %s\n",
1811 GCP_2s (c->prev_peer));
1813 if ( (GNUNET_NO == GCP_is_neighbor (c->next_peer)) ||
1814 (GNUNET_NO == GCP_is_neighbor (c->prev_peer)) )
1816 if (GCC_is_origin (c, GNUNET_YES))
1817 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1818 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1820 LOG (GNUNET_ERROR_TYPE_DEBUG,
1821 " register neighbors failed\n");
1822 LOG (GNUNET_ERROR_TYPE_DEBUG,
1823 " prev: %s, neighbor?: %d\n",
1824 GCP_2s (c->prev_peer),
1825 GCP_is_neighbor (c->prev_peer));
1826 LOG (GNUNET_ERROR_TYPE_DEBUG,
1827 " next: %s, neighbor?: %d\n",
1828 GCP_2s (c->next_peer),
1829 GCP_is_neighbor (c->next_peer));
1830 return GNUNET_SYSERR;
1832 GCP_add_connection (c->next_peer, c, GNUNET_NO);
1833 GCP_add_connection (c->prev_peer, c, GNUNET_YES);
1840 * Remove the connection from the list of both neighbors.
1842 * @param c Connection.
1845 unregister_neighbors (struct CadetConnection *c)
1847 // struct CadetPeer *peer; FIXME dont use next_peer, prev_peer
1848 /* Either already unregistered or never got registered, it's ok either way. */
1849 if (NULL == c->path)
1851 if (NULL != c->next_peer)
1853 GCP_remove_connection (c->next_peer, c);
1854 c->next_peer = NULL;
1856 if (NULL != c->prev_peer)
1858 GCP_remove_connection (c->prev_peer, c);
1859 c->prev_peer = NULL;
1865 * Invalidates all paths towards all peers that comprise the connection which
1866 * rely on the disconnected peer.
1868 * ~O(n^3) (peers in connection * paths/peer * links/path)
1870 * @param c Connection whose peers' paths to clean.
1871 * @param disconnected Peer that disconnected.
1874 invalidate_paths (struct CadetConnection *c,
1875 struct CadetPeer *disconnected)
1877 struct CadetPeer *peer;
1880 for (i = 0; i < c->path->length; i++)
1882 peer = GCP_get_short (c->path->peers[i], GNUNET_NO);
1884 GCP_notify_broken_link (peer, &my_full_id, GCP_get_id (disconnected));
1890 * Bind the connection to the peer and the tunnel to that peer.
1892 * If the peer has no tunnel, create one. Update tunnel and connection
1893 * data structres to reflect new status.
1895 * @param c Connection.
1899 add_to_peer (struct CadetConnection *c,
1900 struct CadetPeer *peer)
1902 GCP_add_tunnel (peer);
1903 c->t = GCP_get_tunnel (peer);
1904 GCT_add_connection (c->t, c);
1909 * Log receipt of message on stderr (INFO level).
1911 * @param message Message received.
1912 * @param peer Peer who sent the message.
1913 * @param hash Connection ID.
1916 log_message (const struct GNUNET_MessageHeader *message,
1917 const struct GNUNET_PeerIdentity *peer,
1918 const struct GNUNET_CADET_Hash *hash)
1924 size = ntohs (message->size);
1925 type = ntohs (message->type);
1928 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
1929 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
1930 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
1931 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
1937 LOG (GNUNET_ERROR_TYPE_INFO, "<%s %s on conn %s from %s, %6u bytes\n",
1938 arrow, GC_m2s (type), GNUNET_h2s (GC_h2hc (hash)),
1939 GNUNET_i2s (peer), (unsigned int) size);
1942 /******************************************************************************/
1943 /******************************** API ***********************************/
1944 /******************************************************************************/
1947 * Core handler for connection creation.
1949 * @param cls Closure (unused).
1950 * @param peer Sender (neighbor).
1951 * @param message Message.
1952 * @return #GNUNET_OK to keep the connection open,
1953 * #GNUNET_SYSERR to close it (signal serious error)
1956 GCC_handle_create (void *cls,
1957 const struct GNUNET_PeerIdentity *peer,
1958 const struct GNUNET_MessageHeader *message)
1960 struct GNUNET_CADET_ConnectionCreate *msg;
1961 struct GNUNET_PeerIdentity *id;
1962 struct GNUNET_CADET_Hash *cid;
1963 struct CadetPeerPath *path;
1964 struct CadetPeer *dest_peer;
1965 struct CadetPeer *orig_peer;
1966 struct CadetConnection *c;
1967 unsigned int own_pos;
1970 GCC_check_connections ();
1972 size = ntohs (message->size);
1973 if (size < sizeof (struct GNUNET_CADET_ConnectionCreate))
1975 GNUNET_break_op (0);
1979 /* Calculate hops */
1980 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
1981 if (size % sizeof (struct GNUNET_PeerIdentity))
1983 GNUNET_break_op (0);
1986 if (0 != size % sizeof (struct GNUNET_PeerIdentity))
1988 GNUNET_break_op (0);
1991 size /= sizeof (struct GNUNET_PeerIdentity);
1994 GNUNET_break_op (0);
1997 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1999 /* Get parameters */
2000 msg = (struct GNUNET_CADET_ConnectionCreate *) message;
2002 log_message (message, peer, cid);
2003 id = (struct GNUNET_PeerIdentity *) &msg[1];
2004 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
2006 /* Create connection */
2007 c = connection_get (cid);
2010 path = path_build_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
2011 size, myid, &own_pos);
2014 /* Path was malformed, probably our own ID was not in it. */
2015 GNUNET_STATISTICS_update (stats, "# malformed paths", 1, GNUNET_NO);
2016 GNUNET_break_op (0);
2022 /* We received this request from a neighbor, we cannot be origin */
2023 GNUNET_STATISTICS_update (stats, "# fake paths", 1, GNUNET_NO);
2024 GNUNET_break_op (0);
2025 path_destroy (path);
2029 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
2030 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
2031 c = GCC_new (cid, NULL, path, own_pos);
2034 if (path->length - 1 == own_pos)
2036 /* If we are destination, why did the creation fail? */
2038 path_destroy (path);
2039 GCC_check_connections ();
2042 send_broken_unknown (cid, &my_full_id,
2043 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
2045 path_destroy (path);
2046 GCC_check_connections ();
2049 GCP_add_path_to_all (path, GNUNET_NO);
2050 connection_reset_timeout (c, GNUNET_YES);
2054 path = path_duplicate (c->path);
2056 if (CADET_CONNECTION_NEW == c->state)
2057 connection_change_state (c, CADET_CONNECTION_SENT);
2059 /* Remember peers */
2060 dest_peer = GCP_get (&id[size - 1], GNUNET_YES);
2061 orig_peer = GCP_get (&id[0], GNUNET_YES);
2063 /* Is it a connection to us? */
2064 if (c->own_pos == path->length - 1)
2066 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
2067 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
2069 add_to_peer (c, orig_peer);
2070 if (GNUNET_YES == does_connection_exist (c))
2072 /* Peer created a connection equal to one we think exists
2074 * Solution: Keep both and postpone disambiguation. In the meantime
2075 * the connection will time out or peer will inform us it is broken.
2078 * - Use explicit duplicate.
2079 * - Accept new conn and destroy the old. (interruption in higher level)
2080 * - Keep the one with higher ID / created by peer with higher ID. */
2081 schedule_check_duplicates (c);
2084 if (CADET_TUNNEL_NEW == GCT_get_cstate (c->t))
2085 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
2087 send_connection_ack (c, GNUNET_NO);
2088 if (CADET_CONNECTION_SENT == c->state)
2089 connection_change_state (c, CADET_CONNECTION_ACK);
2093 /* It's for somebody else! Retransmit. */
2094 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
2095 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
2096 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
2097 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c,
2098 GNUNET_YES, GNUNET_YES,
2101 path_destroy (path);
2102 GCC_check_connections ();
2108 * Core handler for path confirmations.
2110 * @param cls closure
2111 * @param message message
2112 * @param peer peer identity this notification is about
2113 * @return #GNUNET_OK to keep the connection open,
2114 * #GNUNET_SYSERR to close it (signal serious error)
2117 GCC_handle_confirm (void *cls,
2118 const struct GNUNET_PeerIdentity *peer,
2119 const struct GNUNET_MessageHeader *message)
2121 struct GNUNET_CADET_ConnectionACK *msg;
2122 struct CadetConnection *c;
2123 struct CadetPeerPath *p;
2124 struct CadetPeer *pi;
2125 enum CadetConnectionState oldstate;
2128 GCC_check_connections ();
2129 msg = (struct GNUNET_CADET_ConnectionACK *) message;
2130 log_message (message, peer, &msg->cid);
2131 c = connection_get (&msg->cid);
2134 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
2136 LOG (GNUNET_ERROR_TYPE_DEBUG,
2137 " don't know the connection!\n");
2138 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2139 GCC_check_connections ();
2143 if (GNUNET_NO != c->destroy)
2145 GNUNET_assert (CADET_CONNECTION_DESTROYED == c->state);
2146 LOG (GNUNET_ERROR_TYPE_DEBUG,
2147 "connection %s being destroyed, ignoring confirm\n",
2149 GCC_check_connections ();
2153 oldstate = c->state;
2154 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
2155 pi = GCP_get (peer, GNUNET_YES);
2156 if (get_next_hop (c) == pi)
2158 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
2160 if (CADET_CONNECTION_SENT == oldstate)
2161 connection_change_state (c, CADET_CONNECTION_ACK);
2163 else if (get_prev_hop (c) == pi)
2165 LOG (GNUNET_ERROR_TYPE_DEBUG, " FINAL ACK\n");
2167 connection_change_state (c, CADET_CONNECTION_READY);
2171 GNUNET_break_op (0);
2175 connection_reset_timeout (c, fwd);
2177 /* Add path to peers? */
2181 GCP_add_path_to_all (p, GNUNET_YES);
2188 /* Message for us as creator? */
2189 if (GCC_is_origin (c, GNUNET_YES))
2191 if (GNUNET_NO != fwd)
2193 GNUNET_break_op (0);
2196 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
2198 /* If just created, cancel the short timeout and start a long one */
2199 if (CADET_CONNECTION_SENT == oldstate)
2200 connection_reset_timeout (c, GNUNET_YES);
2202 /* Change connection state */
2203 connection_change_state (c, CADET_CONNECTION_READY);
2204 send_connection_ack (c, GNUNET_YES);
2206 /* Change tunnel state, trigger KX */
2207 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2208 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2209 GCC_check_connections ();
2213 /* Message for us as destination? */
2214 if (GCC_is_terminal (c, GNUNET_YES))
2216 if (GNUNET_YES != fwd)
2218 GNUNET_break_op (0);
2221 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
2223 /* If just created, cancel the short timeout and start a long one */
2224 if (CADET_CONNECTION_ACK == oldstate)
2225 connection_reset_timeout (c, GNUNET_NO);
2227 /* Change tunnel state */
2228 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2229 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2230 GCC_check_connections ();
2234 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2235 GNUNET_assert (NULL ==
2236 GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2237 GNUNET_YES, NULL, NULL));
2238 GCC_check_connections ();
2244 * Core handler for notifications of broken connections.
2246 * @param cls Closure (unused).
2247 * @param id Peer identity of sending neighbor.
2248 * @param message Message.
2249 * @return #GNUNET_OK to keep the connection open,
2250 * #GNUNET_SYSERR to close it (signal serious error)
2253 GCC_handle_broken (void* cls,
2254 const struct GNUNET_PeerIdentity* id,
2255 const struct GNUNET_MessageHeader* message)
2257 struct GNUNET_CADET_ConnectionBroken *msg;
2258 struct CadetConnection *c;
2259 struct CadetTunnel *t;
2263 GCC_check_connections ();
2264 msg = (struct GNUNET_CADET_ConnectionBroken *) message;
2265 log_message (message, id, &msg->cid);
2266 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2267 GNUNET_i2s (&msg->peer1));
2268 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2269 GNUNET_i2s (&msg->peer2));
2270 c = connection_get (&msg->cid);
2273 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
2274 GCC_check_connections ();
2280 fwd = is_fwd (c, id);
2282 if (GCC_is_terminal (c, fwd))
2284 struct CadetPeer *endpoint;
2288 /* A terminal connection should not have 't' set to NULL. */
2290 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
2293 endpoint = GCP_get_short (c->path->peers[c->path->length - 1], GNUNET_YES);
2294 if (2 < c->path->length)
2295 path_invalidate (c->path);
2296 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
2298 connection_change_state (c, CADET_CONNECTION_BROKEN);
2299 GCT_remove_connection (t, c);
2302 pending = c->pending_messages;
2304 resend_messages_and_destroy (c, !fwd);
2310 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2311 GNUNET_YES, NULL, NULL));
2312 connection_cancel_queues (c, !fwd);
2314 GCC_check_connections ();
2320 * Core handler for tunnel destruction
2322 * @param cls Closure (unused).
2323 * @param peer Peer identity of sending neighbor.
2324 * @param message Message.
2325 * @return #GNUNET_OK to keep the connection open,
2326 * #GNUNET_SYSERR to close it (signal serious error)
2329 GCC_handle_destroy (void *cls,
2330 const struct GNUNET_PeerIdentity *peer,
2331 const struct GNUNET_MessageHeader *message)
2333 const struct GNUNET_CADET_ConnectionDestroy *msg;
2334 struct CadetConnection *c;
2337 GCC_check_connections ();
2338 msg = (const struct GNUNET_CADET_ConnectionDestroy *) message;
2339 log_message (message, peer, &msg->cid);
2340 c = connection_get (&msg->cid);
2343 /* Probably already got the message from another path,
2344 * destroyed the tunnel and retransmitted to children.
2347 GNUNET_STATISTICS_update (stats,
2348 "# control on unknown connection",
2350 LOG (GNUNET_ERROR_TYPE_DEBUG,
2351 " connection unknown: already destroyed?\n");
2352 GCC_check_connections ();
2355 fwd = is_fwd (c, peer);
2356 if (GNUNET_SYSERR == fwd)
2358 GNUNET_break_op (0); /* FIXME */
2361 if (GNUNET_NO == GCC_is_terminal (c, fwd))
2363 GNUNET_assert (NULL ==
2364 GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2365 GNUNET_YES, NULL, NULL));
2367 else if (0 == c->pending_messages)
2369 LOG (GNUNET_ERROR_TYPE_DEBUG, " directly destroying connection!\n");
2371 GCC_check_connections ();
2377 GCT_remove_connection (c->t, c);
2380 GCC_check_connections ();
2386 * Check the message against internal state and test if it goes FWD or BCK.
2388 * Updates the PID, state and timeout values for the connection.
2390 * @param message Message to check. It must belong to an existing connection.
2391 * @param minimum_size The message cannot be smaller than this value.
2392 * @param cid Connection ID (even if @a c is NULL, the ID is still needed).
2393 * @param c Connection this message should belong. If NULL, check fails.
2394 * @param neighbor Neighbor that sent the message.
2397 check_message (const struct GNUNET_MessageHeader *message,
2398 size_t minimum_size,
2399 const struct GNUNET_CADET_Hash* cid,
2400 struct CadetConnection *c,
2401 const struct GNUNET_PeerIdentity *neighbor,
2404 GNUNET_PEER_Id neighbor_id;
2405 struct CadetFlowControl *fc;
2406 struct CadetPeer *hop;
2411 if (ntohs (message->size) < minimum_size)
2413 GNUNET_break_op (0);
2414 LOG (GNUNET_ERROR_TYPE_WARNING, "Size %u < %u\n",
2415 ntohs (message->size), minimum_size);
2416 return GNUNET_SYSERR;
2419 /* Check connection */
2422 GNUNET_STATISTICS_update (stats,
2423 "# unknown connection",
2425 LOG (GNUNET_ERROR_TYPE_DEBUG,
2426 "%s on unknown connection %s\n",
2427 GC_m2s (ntohs (message->type)),
2428 GNUNET_h2s (GC_h2hc (cid)));
2429 send_broken_unknown (cid,
2433 return GNUNET_SYSERR;
2436 /* Check if origin is as expected */
2437 neighbor_id = GNUNET_PEER_search (neighbor);
2438 hop = get_prev_hop (c);
2439 if (neighbor_id == GCP_get_short_id (hop))
2445 hop = get_next_hop (c);
2446 GNUNET_break (hop == c->next_peer);
2447 if (neighbor_id == GCP_get_short_id (hop))
2453 /* Unexpected peer sending traffic on a connection. */
2454 GNUNET_break_op (0);
2455 return GNUNET_SYSERR;
2459 /* Check PID for payload messages */
2460 type = ntohs (message->type);
2461 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type
2462 || GNUNET_MESSAGE_TYPE_CADET_AX == type)
2464 fc = fwd ? &c->bck_fc : &c->fwd_fc;
2465 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u - %u)\n",
2466 pid, fc->last_pid_recv + 1, fc->last_ack_sent);
2467 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
2469 GNUNET_break_op (0);
2470 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
2471 LOG (GNUNET_ERROR_TYPE_WARNING, "Received PID %u, (prev %u), ACK %u\n",
2472 pid, fc->last_pid_recv, fc->last_ack_sent);
2473 return GNUNET_SYSERR;
2475 if (GC_is_pid_bigger (pid, fc->last_pid_recv))
2479 delta = pid - fc->last_pid_recv;
2480 fc->last_pid_recv = pid;
2481 fc->recv_bitmap <<= delta;
2482 fc->recv_bitmap |= 1;
2486 GNUNET_STATISTICS_update (stats, "# out of order PID", 1, GNUNET_NO);
2487 if (GNUNET_NO == is_ooo_ok (fc->last_pid_recv, pid, fc->recv_bitmap))
2489 LOG (GNUNET_ERROR_TYPE_WARNING, "PID %u unexpected (%u+), dropping!\n",
2490 pid, fc->last_pid_recv - 31);
2491 return GNUNET_SYSERR;
2493 fc->recv_bitmap |= get_recv_bitmask (fc->last_pid_recv, pid);
2497 /* Count as connection confirmation. */
2498 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2500 connection_change_state (c, CADET_CONNECTION_READY);
2503 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2504 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2507 connection_reset_timeout (c, fwd);
2514 * Generic handler for cadet network encrypted traffic.
2516 * @param peer Peer identity this notification is about.
2517 * @param msg Encrypted message.
2518 * @return #GNUNET_OK to keep the connection open,
2519 * #GNUNET_SYSERR to close it (signal serious error)
2522 handle_cadet_encrypted (const struct GNUNET_PeerIdentity *peer,
2523 const struct GNUNET_MessageHeader *message)
2525 const struct GNUNET_CADET_Encrypted *otr_msg;
2526 const struct GNUNET_CADET_AX *ax_msg;
2527 const struct GNUNET_CADET_Hash* cid;
2528 struct CadetConnection *c;
2529 size_t minimum_size;
2535 GCC_check_connections ();
2536 if (GNUNET_MESSAGE_TYPE_CADET_AX == ntohs (message->type))
2538 overhead = sizeof (struct GNUNET_CADET_AX);
2539 ax_msg = (const struct GNUNET_CADET_AX *) message;
2541 pid = ntohl (ax_msg->pid);
2546 overhead = sizeof (struct GNUNET_CADET_Encrypted);
2547 otr_msg = (const struct GNUNET_CADET_Encrypted *) message;
2548 cid = &otr_msg->cid;
2549 pid = ntohl (otr_msg->pid);
2552 log_message (message, peer, cid);
2554 minimum_size = sizeof (struct GNUNET_MessageHeader) + overhead;
2555 c = connection_get (cid);
2556 fwd = check_message (message,
2563 /* If something went wrong, discard message. */
2564 if (GNUNET_SYSERR == fwd)
2566 GCC_check_connections ();
2570 /* Is this message for us? */
2571 if (GCC_is_terminal (c, fwd))
2573 GNUNET_STATISTICS_update (stats, "# received encrypted", 1, GNUNET_NO);
2577 GNUNET_break (GNUNET_NO != c->destroy);
2580 GCT_handle_encrypted (c->t, message);
2581 GCC_send_ack (c, fwd, GNUNET_NO);
2582 GCC_check_connections ();
2586 /* Message not for us: forward to next hop */
2587 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2588 if (NULL != otr_msg) /* only otr has ttl */
2590 ttl = ntohl (otr_msg->ttl);
2591 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
2594 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
2595 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
2596 GCC_send_ack (c, fwd, GNUNET_NO);
2597 GCC_check_connections ();
2602 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2603 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2604 GNUNET_NO, NULL, NULL));
2605 GCC_check_connections ();
2611 * Generic handler for cadet network encrypted traffic.
2613 * @param peer Peer identity this notification is about.
2614 * @param msg Encrypted message.
2615 * @return #GNUNET_OK to keep the connection open,
2616 * #GNUNET_SYSERR to close it (signal serious error)
2619 handle_cadet_kx (const struct GNUNET_PeerIdentity *peer,
2620 const struct GNUNET_CADET_KX *msg)
2622 const struct GNUNET_CADET_Hash* cid;
2623 struct CadetConnection *c;
2624 size_t expected_size;
2627 GCC_check_connections ();
2629 log_message (&msg->header, peer, cid);
2631 expected_size = sizeof (struct GNUNET_CADET_KX)
2632 + sizeof (struct GNUNET_MessageHeader);
2633 c = connection_get (cid);
2634 fwd = check_message (&msg->header,
2641 /* If something went wrong, discard message. */
2642 if (GNUNET_SYSERR == fwd)
2645 /* Is this message for us? */
2646 if (GCC_is_terminal (c, fwd))
2648 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2649 GNUNET_STATISTICS_update (stats, "# received KX", 1, GNUNET_NO);
2655 GCT_handle_kx (c->t, &msg[1].header);
2656 GCC_check_connections ();
2660 /* Message not for us: forward to next hop */
2661 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2662 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2663 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2664 GNUNET_NO, NULL, NULL));
2665 GCC_check_connections ();
2671 * Core handler for key exchange traffic (ephemeral key, ping, pong).
2673 * @param cls Closure (unused).
2674 * @param message Message received.
2675 * @param peer Peer who sent the message.
2676 * @return #GNUNET_OK to keep the connection open,
2677 * #GNUNET_SYSERR to close it (signal serious error)
2680 GCC_handle_kx (void *cls,
2681 const struct GNUNET_PeerIdentity *peer,
2682 const struct GNUNET_MessageHeader *message)
2684 GCC_check_connections ();
2685 return handle_cadet_kx (peer, (struct GNUNET_CADET_KX *) message);
2690 * Core handler for encrypted cadet network traffic (channel mgmt, data).
2692 * @param cls Closure (unused).
2693 * @param message Message received.
2694 * @param peer Peer who sent the message.
2695 * @return #GNUNET_OK to keep the connection open,
2696 * #GNUNET_SYSERR to close it (signal serious error)
2699 GCC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
2700 const struct GNUNET_MessageHeader *message)
2702 GCC_check_connections ();
2703 return handle_cadet_encrypted (peer, message);
2708 * Core handler for cadet network traffic point-to-point acks.
2710 * @param cls closure
2711 * @param message message
2712 * @param peer peer identity this notification is about
2713 * @return #GNUNET_OK to keep the connection open,
2714 * #GNUNET_SYSERR to close it (signal serious error)
2717 GCC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
2718 const struct GNUNET_MessageHeader *message)
2720 struct GNUNET_CADET_ACK *msg;
2721 struct CadetConnection *c;
2722 struct CadetFlowControl *fc;
2727 GCC_check_connections ();
2728 msg = (struct GNUNET_CADET_ACK *) message;
2729 log_message (message, peer, &msg->cid);
2730 c = connection_get (&msg->cid);
2733 GNUNET_STATISTICS_update (stats,
2734 "# ack on unknown connection",
2737 send_broken_unknown (&msg->cid,
2741 GCC_check_connections ();
2745 /* Is this a forward or backward ACK? */
2746 id = GNUNET_PEER_search (peer);
2747 if (GCP_get_short_id (get_next_hop (c)) == id)
2752 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2759 GNUNET_break_op (0);
2763 ack = ntohl (msg->ack);
2764 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s ACK %u (was %u)\n",
2765 GC_f2s (fwd), ack, fc->last_ack_recv);
2766 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2767 fc->last_ack_recv = ack;
2769 /* Cancel polling if the ACK is big enough. */
2770 if (NULL != fc->poll_task &&
2771 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2773 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2774 GNUNET_SCHEDULER_cancel (fc->poll_task);
2775 fc->poll_task = NULL;
2776 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2779 connection_unlock_queue (c, fwd);
2780 GCC_check_connections ();
2786 * Core handler for cadet network traffic point-to-point ack polls.
2788 * @param cls closure
2789 * @param message message
2790 * @param peer peer identity this notification is about
2791 * @return #GNUNET_OK to keep the connection open,
2792 * #GNUNET_SYSERR to close it (signal serious error)
2795 GCC_handle_poll (void *cls,
2796 const struct GNUNET_PeerIdentity *peer,
2797 const struct GNUNET_MessageHeader *message)
2799 struct GNUNET_CADET_Poll *msg;
2800 struct CadetConnection *c;
2801 struct CadetFlowControl *fc;
2806 GCC_check_connections ();
2807 msg = (struct GNUNET_CADET_Poll *) message;
2808 log_message (message, peer, &msg->cid);
2809 c = connection_get (&msg->cid);
2812 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2814 LOG (GNUNET_ERROR_TYPE_DEBUG,
2815 "POLL message on unknown connection %s!\n",
2816 GNUNET_h2s (GC_h2hc (&msg->cid)));
2817 send_broken_unknown (&msg->cid,
2821 GCC_check_connections ();
2825 /* Is this a forward or backward ACK?
2826 * Note: a poll should never be needed in a loopback case,
2827 * since there is no possiblility of packet loss there, so
2828 * this way of discerining FWD/BCK should not be a problem.
2830 id = GNUNET_PEER_search (peer);
2831 if (GCP_get_short_id (get_next_hop (c)) == id)
2833 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2836 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2838 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2843 GNUNET_break_op (0);
2847 pid = ntohl (msg->pid);
2848 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2849 fc->last_pid_recv = pid;
2850 fwd = fc == &c->bck_fc;
2851 GCC_send_ack (c, fwd, GNUNET_YES);
2852 GCC_check_connections ();
2859 * Send an ACK on the appropriate connection/channel, depending on
2860 * the direction and the position of the peer.
2862 * @param c Which connection to send the hop-by-hop ACK.
2863 * @param fwd Is this a fwd ACK? (will go dest->root).
2864 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2867 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
2869 unsigned int buffer;
2871 GCC_check_connections ();
2872 LOG (GNUNET_ERROR_TYPE_DEBUG, "GCC send %s ACK on %s\n",
2873 GC_f2s (fwd), GCC_2s (c));
2881 if (GNUNET_NO != c->destroy)
2883 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2884 GCC_check_connections ();
2888 /* Get available buffer space */
2889 if (GCC_is_terminal (c, fwd))
2891 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2892 buffer = GCT_get_channels_buffer (c->t);
2896 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2897 buffer = GCC_get_buffer (c, fwd);
2899 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2900 if (0 == buffer && GNUNET_NO == force)
2902 GCC_check_connections ();
2906 /* Send available buffer space */
2907 if (GCC_is_origin (c, fwd))
2909 GNUNET_assert (NULL != c->t);
2910 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2911 GCT_unchoke_channels (c->t);
2915 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2916 send_ack (c, buffer, fwd, force);
2918 GCC_check_connections ();
2923 * Initialize the connections subsystem
2925 * @param c Configuration handle.
2928 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2930 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2932 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2935 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2936 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2937 GNUNET_SCHEDULER_shutdown ();
2942 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2945 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2946 "CADET", "MAX_CONNECTIONS", "MISSING");
2947 GNUNET_SCHEDULER_shutdown ();
2952 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2953 &refresh_connection_time))
2955 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2956 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2957 GNUNET_SCHEDULER_shutdown ();
2960 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2961 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2966 * Destroy each connection on shutdown.
2968 * @param cls Closure (unused).
2969 * @param key Current key code (CID, unused).
2970 * @param value Value in the hash map (`struct CadetConnection`)
2972 * @return #GNUNET_YES, because we should continue to iterate
2975 shutdown_iterator (void *cls,
2976 const struct GNUNET_HashCode *key,
2979 struct CadetConnection *c = value;
2981 c->state = CADET_CONNECTION_DESTROYED;
2988 * Shut down the connections subsystem.
2993 LOG (GNUNET_ERROR_TYPE_DEBUG, "Shutting down connections\n");
2994 GCC_check_connections ();
2995 GNUNET_CONTAINER_multihashmap_iterate (connections,
2998 GNUNET_CONTAINER_multihashmap_destroy (connections);
3004 * Create a connection.
3006 * @param cid Connection ID (either created locally or imposed remotely).
3007 * @param t Tunnel this connection belongs to (or NULL);
3008 * @param path Path this connection has to use (copy is made).
3009 * @param own_pos Own position in the @c path path.
3011 * @return Newly created connection, NULL in case of error (own id not in path).
3013 struct CadetConnection *
3014 GCC_new (const struct GNUNET_CADET_Hash *cid,
3015 struct CadetTunnel *t,
3016 struct CadetPeerPath *path,
3017 unsigned int own_pos)
3019 struct CadetConnection *c;
3020 struct CadetPeerPath *cpath;
3022 GCC_check_connections ();
3023 cpath = path_duplicate (path);
3024 GNUNET_assert (NULL != cpath);
3025 c = GNUNET_new (struct CadetConnection);
3027 GNUNET_assert (GNUNET_OK ==
3028 GNUNET_CONTAINER_multihashmap_put (connections,
3030 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
3031 fc_init (&c->fwd_fc);
3032 fc_init (&c->bck_fc);
3037 GNUNET_assert (own_pos <= cpath->length - 1);
3038 c->own_pos = own_pos;
3041 if (GNUNET_OK != register_neighbors (c))
3045 /* We were the origin of this request, this means we have invalid
3046 * info about the paths to reach the destination. We must invalidate
3047 * the *original* path to avoid trying it again in the next minute.
3049 if (2 < path->length)
3050 path_invalidate (path);
3054 GCT_debug(t, GNUNET_ERROR_TYPE_WARNING);
3058 path_destroy (c->path);
3063 LOG (GNUNET_ERROR_TYPE_INFO, "New connection %s\n", GCC_2s (c));
3064 GCC_check_connections ();
3070 GCC_destroy (struct CadetConnection *c)
3072 GCC_check_connections ();
3079 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
3080 return; /* -> message_sent -> GCC_destroy. Don't loop. */
3083 LOG (GNUNET_ERROR_TYPE_DEBUG,
3084 "destroying connection %s\n",
3086 LOG (GNUNET_ERROR_TYPE_DEBUG,
3087 " fc's f: %p, b: %p\n",
3088 &c->fwd_fc, &c->bck_fc);
3089 LOG (GNUNET_ERROR_TYPE_DEBUG,
3090 " fc tasks f: %u, b: %u\n",
3091 c->fwd_fc.poll_task,
3092 c->bck_fc.poll_task);
3094 /* Cancel all traffic */
3095 if (NULL != c->path)
3097 connection_cancel_queues (c, GNUNET_YES);
3098 connection_cancel_queues (c, GNUNET_NO);
3100 unregister_neighbors (c);
3101 path_destroy (c->path);
3104 /* Delete from tunnel */
3106 GCT_remove_connection (c->t, c);
3108 if (NULL != c->check_duplicates_task)
3109 GNUNET_SCHEDULER_cancel (c->check_duplicates_task);
3110 if (NULL != c->fwd_maintenance_task)
3111 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
3112 if (NULL != c->bck_maintenance_task)
3113 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
3115 if (GNUNET_NO == c->was_removed)
3117 GNUNET_break (GNUNET_YES ==
3118 GNUNET_CONTAINER_multihashmap_remove (connections,
3122 GNUNET_STATISTICS_update (stats,
3127 GCC_check_connections ();
3132 * Get the connection ID.
3134 * @param c Connection to get the ID from.
3136 * @return ID of the connection.
3138 const struct GNUNET_CADET_Hash *
3139 GCC_get_id (const struct CadetConnection *c)
3146 * Get the connection ID.
3148 * @param c Connection to get the ID from.
3150 * @return ID of the connection.
3152 const struct GNUNET_HashCode *
3153 GCC_get_h (const struct CadetConnection *c)
3155 return GC_h2hc (&c->id);
3160 * Get the connection path.
3162 * @param c Connection to get the path from.
3164 * @return path used by the connection.
3166 const struct CadetPeerPath *
3167 GCC_get_path (const struct CadetConnection *c)
3169 if (GNUNET_NO == c->destroy)
3176 * Get the connection state.
3178 * @param c Connection to get the state from.
3180 * @return state of the connection.
3182 enum CadetConnectionState
3183 GCC_get_state (const struct CadetConnection *c)
3189 * Get the connection tunnel.
3191 * @param c Connection to get the tunnel from.
3193 * @return tunnel of the connection.
3195 struct CadetTunnel *
3196 GCC_get_tunnel (const struct CadetConnection *c)
3203 * Get free buffer space in a connection.
3205 * @param c Connection.
3206 * @param fwd Is query about FWD traffic?
3208 * @return Free buffer space [0 - max_msgs_queue/max_connections]
3211 GCC_get_buffer (struct CadetConnection *c, int fwd)
3213 struct CadetFlowControl *fc;
3215 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3217 LOG (GNUNET_ERROR_TYPE_DEBUG, " Get %s buffer on %s: %u - %u\n",
3218 GC_f2s (fwd), GCC_2s (c), fc->queue_max, fc->queue_n);
3219 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
3221 return (fc->queue_max - fc->queue_n);
3226 * Get how many messages have we allowed to send to us from a direction.
3228 * @param c Connection.
3229 * @param fwd Are we asking about traffic from FWD (BCK messages)?
3231 * @return last_ack_sent - last_pid_recv
3234 GCC_get_allowed (struct CadetConnection *c, int fwd)
3236 struct CadetFlowControl *fc;
3238 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3239 if (CADET_CONNECTION_READY != c->state
3240 || GC_is_pid_bigger (fc->last_pid_recv, fc->last_ack_sent))
3244 return (fc->last_ack_sent - fc->last_pid_recv);
3249 * Get messages queued in a connection.
3251 * @param c Connection.
3252 * @param fwd Is query about FWD traffic?
3254 * @return Number of messages queued.
3257 GCC_get_qn (struct CadetConnection *c, int fwd)
3259 struct CadetFlowControl *fc;
3261 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3268 * Get next PID to use.
3270 * @param c Connection.
3271 * @param fwd Is query about FWD traffic?
3273 * @return Last PID used + 1.
3276 GCC_get_pid (struct CadetConnection *c, int fwd)
3278 struct CadetFlowControl *fc;
3280 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3282 return fc->last_pid_sent + 1;
3287 * Allow the connection to advertise a buffer of the given size.
3289 * The connection will send an @c fwd ACK message (so: in direction !fwd)
3290 * allowing up to last_pid_recv + buffer.
3292 * @param c Connection.
3293 * @param buffer How many more messages the connection can accept.
3294 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
3297 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
3299 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
3300 GCC_2s (c), buffer, GC_f2s (fwd));
3301 send_ack (c, buffer, fwd, GNUNET_NO);
3306 * Notify other peers on a connection of a broken link. Mark connections
3307 * to destroy after all traffic has been sent.
3309 * @param c Connection on which there has been a disconnection.
3310 * @param peer Peer that disconnected.
3313 GCC_neighbor_disconnected (struct CadetConnection *c, struct CadetPeer *peer)
3315 struct CadetFlowControl *fc;
3316 struct CadetPeer *hop;
3320 GCC_check_connections ();
3321 strncpy (peer_name, GCP_2s (peer), 16);
3322 peer_name[15] = '\0';
3323 LOG (GNUNET_ERROR_TYPE_DEBUG,
3324 "shutting down %s, %s disconnected\n",
3325 GCC_2s (c), peer_name);
3327 invalidate_paths (c, peer);
3329 hop = get_prev_hop (c);
3332 /* Path was NULL, we should have deleted the connection. */
3336 fwd = (peer == hop);
3337 if ( (GNUNET_YES == GCC_is_terminal (c, fwd)) ||
3338 (GNUNET_NO != c->destroy) )
3340 /* Local shutdown, or other peer already down (hence 'c->destroy');
3341 so there is no one to notify about this, just clean up. */
3343 GCC_check_connections ();
3346 /* Mark FlowControl towards the peer as unavaliable. */
3347 fc = fwd ? &c->bck_fc : &c->fwd_fc;
3350 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
3352 /* Connection will have at least one pending message
3353 * (the one we just scheduled), so delay destruction
3354 * and remove from map so we don't use accidentally. */
3356 GNUNET_assert (GNUNET_NO == c->was_removed);
3357 c->was_removed = GNUNET_YES;
3358 GNUNET_break (GNUNET_YES ==
3359 GNUNET_CONTAINER_multihashmap_remove (connections,
3362 /* Cancel queue in the direction that just died. */
3363 connection_cancel_queues (c, ! fwd);
3364 GCC_stop_poll (c, ! fwd);
3365 unregister_neighbors (c);
3366 GCC_check_connections ();
3371 * Is this peer the first one on the connection?
3373 * @param c Connection.
3374 * @param fwd Is this about fwd traffic?
3376 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
3379 GCC_is_origin (struct CadetConnection *c, int fwd)
3381 if (!fwd && c->path->length - 1 == c->own_pos )
3383 if (fwd && 0 == c->own_pos)
3390 * Is this peer the last one on the connection?
3392 * @param c Connection.
3393 * @param fwd Is this about fwd traffic?
3394 * Note that the ROOT is the terminal for BCK traffic!
3396 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
3399 GCC_is_terminal (struct CadetConnection *c, int fwd)
3401 return GCC_is_origin (c, ! fwd);
3406 * See if we are allowed to send by the next hop in the given direction.
3408 * @param c Connection.
3409 * @param fwd Is this about fwd traffic?
3411 * @return #GNUNET_YES in case it's OK to send.
3414 GCC_is_sendable (struct CadetConnection *c, int fwd)
3416 struct CadetFlowControl *fc;
3418 LOG (GNUNET_ERROR_TYPE_DEBUG,
3419 " checking sendability of %s traffic on %s\n",
3420 GC_f2s (fwd), GCC_2s (c));
3426 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3427 LOG (GNUNET_ERROR_TYPE_DEBUG,
3428 " last ack recv: %u, last pid sent: %u\n",
3429 fc->last_ack_recv, fc->last_pid_sent);
3430 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
3432 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
3435 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
3441 * Check if this connection is a direct one (never trim a direct connection).
3443 * @param c Connection.
3445 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
3448 GCC_is_direct (struct CadetConnection *c)
3450 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
3455 * Sends an already built message on a connection, properly registering
3456 * all used resources.
3458 * @param message Message to send. Function makes a copy of it.
3459 * If message is not hop-by-hop, decrements TTL of copy.
3460 * @param payload_type Type of payload, in case the message is encrypted.
3461 * @param c Connection on which this message is transmitted.
3462 * @param fwd Is this a fwd message?
3463 * @param force Force the connection to accept the message (buffer overfill).
3464 * @param cont Continuation called once message is sent. Can be NULL.
3465 * @param cont_cls Closure for @c cont.
3467 * @return Handle to cancel the message before it's sent.
3468 * NULL on error or if @c cont is NULL.
3469 * Invalid on @c cont call.
3471 struct CadetConnectionQueue *
3472 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
3473 uint16_t payload_type, uint32_t payload_id,
3474 struct CadetConnection *c, int fwd, int force,
3475 GCC_sent cont, void *cont_cls)
3477 struct CadetFlowControl *fc;
3478 struct CadetConnectionQueue *q;
3484 GCC_check_connections ();
3485 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3486 if (0 == fc->queue_max)
3492 size = ntohs (message->size);
3493 data = GNUNET_malloc (size);
3494 GNUNET_memcpy (data, message, size);
3495 type = ntohs (message->type);
3496 LOG (GNUNET_ERROR_TYPE_INFO,
3497 "--> %s (%s %4u) on conn %s (%p) %s [%5u]\n",
3498 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), c,
3500 droppable = GNUNET_NO == force;
3503 struct GNUNET_CADET_AX *axmsg;
3504 struct GNUNET_CADET_Encrypted *emsg;
3505 struct GNUNET_CADET_KX *kmsg;
3506 struct GNUNET_CADET_ACK *amsg;
3507 struct GNUNET_CADET_Poll *pmsg;
3508 struct GNUNET_CADET_ConnectionDestroy *dmsg;
3509 struct GNUNET_CADET_ConnectionBroken *bmsg;
3512 case GNUNET_MESSAGE_TYPE_CADET_AX:
3513 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
3514 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
3516 emsg = (struct GNUNET_CADET_Encrypted *) data;
3517 ttl = ntohl (emsg->ttl);
3520 GNUNET_break_op (0);
3525 emsg->ttl = htonl (ttl - 1);
3529 axmsg = (struct GNUNET_CADET_AX *) data;
3532 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
3533 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
3534 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
3535 if (GNUNET_YES == droppable)
3541 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
3545 case GNUNET_MESSAGE_TYPE_CADET_KX:
3546 kmsg = (struct GNUNET_CADET_KX *) data;
3550 case GNUNET_MESSAGE_TYPE_CADET_ACK:
3551 amsg = (struct GNUNET_CADET_ACK *) data;
3553 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
3554 droppable = GNUNET_NO;
3557 case GNUNET_MESSAGE_TYPE_CADET_POLL:
3558 pmsg = (struct GNUNET_CADET_Poll *) data;
3560 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL %u\n", ntohl (pmsg->pid));
3561 droppable = GNUNET_NO;
3564 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
3565 dmsg = (struct GNUNET_CADET_ConnectionDestroy *) data;
3569 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
3570 bmsg = (struct GNUNET_CADET_ConnectionBroken *) data;
3574 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
3575 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
3584 if (fc->queue_n > fc->queue_max && droppable)
3586 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
3589 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue full: %u/%u\n",
3590 fc->queue_n, fc->queue_max);
3591 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type
3592 || GNUNET_MESSAGE_TYPE_CADET_AX == type)
3597 return NULL; /* Drop this message */
3600 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %s %u\n",
3601 GCC_2s (c), c->pending_messages);
3602 c->pending_messages++;
3604 q = GNUNET_new (struct CadetConnectionQueue);
3605 q->forced = !droppable;
3606 q->q = GCP_queue_add (get_hop (c, fwd), data, type, payload_type, payload_id,
3607 size, c, fwd, &conn_message_sent, q);
3610 LOG (GNUNET_ERROR_TYPE_DEBUG, "dropping msg on %s, NULL q\n", GCC_2s (c));
3613 GCC_check_connections ();
3617 q->cont_cls = cont_cls;
3618 GCC_check_connections ();
3619 return (NULL == cont) ? NULL : q;
3624 * Cancel a previously sent message while it's in the queue.
3626 * ONLY can be called before the continuation given to the send function
3627 * is called. Once the continuation is called, the message is no longer in the
3630 * @param q Handle to the queue.
3633 GCC_cancel (struct CadetConnectionQueue *q)
3635 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GCC cancel message\n");
3637 /* queue destroy calls message_sent, which calls q->cont and frees q */
3638 GCP_queue_destroy (q->q, GNUNET_YES, GNUNET_NO, 0);
3639 GCC_check_connections ();
3644 * Sends a CREATE CONNECTION message for a path to a peer.
3645 * Changes the connection and tunnel states if necessary.
3647 * @param connection Connection to create.
3650 GCC_send_create (struct CadetConnection *connection)
3652 enum CadetTunnelCState state;
3655 GCC_check_connections ();
3656 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3657 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
3659 LOG (GNUNET_ERROR_TYPE_INFO, "==> %s %19s on conn %s (%p) FWD [%5u]\n",
3660 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE), "",
3661 GCC_2s (connection), connection, size);
3662 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3663 connection, connection->pending_messages);
3664 connection->pending_messages++;
3666 connection->maintenance_q =
3667 GCP_queue_add (get_next_hop (connection), NULL,
3668 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, UINT16_MAX, 0,
3669 size, connection, GNUNET_YES, &conn_message_sent, NULL);
3671 state = GCT_get_cstate (connection->t);
3672 if (CADET_TUNNEL_SEARCHING == state || CADET_TUNNEL_NEW == state)
3673 GCT_change_cstate (connection->t, CADET_TUNNEL_WAITING);
3674 if (CADET_CONNECTION_NEW == connection->state)
3675 connection_change_state (connection, CADET_CONNECTION_SENT);
3676 GCC_check_connections ();
3681 * Send a message to all peers in this connection that the connection
3682 * is no longer valid.
3684 * If some peer should not receive the message, it should be zero'ed out
3685 * before calling this function.
3687 * @param c The connection whose peers to notify.
3690 GCC_send_destroy (struct CadetConnection *c)
3692 struct GNUNET_CADET_ConnectionDestroy msg;
3694 if (GNUNET_YES == c->destroy)
3696 GCC_check_connections ();
3697 msg.header.size = htons (sizeof (msg));
3698 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
3700 LOG (GNUNET_ERROR_TYPE_DEBUG,
3701 " sending connection destroy for connection %s\n",
3704 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3705 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3707 GNUNET_YES, NULL, NULL));
3708 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3709 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3711 GNUNET_YES, NULL, NULL));
3713 GCC_check_connections ();
3718 * @brief Start a polling timer for the connection.
3720 * When a neighbor does not accept more traffic on the connection it could be
3721 * caused by a simple congestion or by a lost ACK. Polling enables to check
3722 * for the lastest ACK status for a connection.
3724 * @param c Connection.
3725 * @param fwd Should we poll in the FWD direction?
3728 GCC_start_poll (struct CadetConnection *c, int fwd)
3730 struct CadetFlowControl *fc;
3732 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3733 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL %s requested\n",
3735 if (NULL != fc->poll_task || NULL != fc->poll_msg)
3737 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL already in progress (t: %p, m: %p)\n",
3738 fc->poll_task, fc->poll_msg);
3741 if (0 == fc->queue_max)
3743 /* Should not be needed, traffic should've been cancelled. */
3745 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL not possible, peer disconnected\n");
3748 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL started on request\n");
3749 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
3756 * @brief Stop polling a connection for ACKs.
3758 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3760 * @param c Connection.
3761 * @param fwd Should we stop the poll in the FWD direction?
3764 GCC_stop_poll (struct CadetConnection *c, int fwd)
3766 struct CadetFlowControl *fc;
3768 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3769 if (NULL != fc->poll_task)
3771 GNUNET_SCHEDULER_cancel (fc->poll_task);
3772 fc->poll_task = NULL;
3774 if (NULL != fc->poll_msg)
3776 GCC_cancel (fc->poll_msg);
3777 fc->poll_msg = NULL;
3783 * Get a (static) string for a connection.
3785 * @param c Connection.
3788 GCC_2s (const struct CadetConnection *c)
3795 static char buf[128];
3797 SPRINTF (buf, "%s (->%s)",
3798 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3801 return GNUNET_h2s (GC_h2hc (&c->id));
3806 * Log all possible info about the connection state.
3808 * @param c Connection to debug.
3809 * @param level Debug level to use.
3812 GCC_debug (const struct CadetConnection *c, enum GNUNET_ErrorType level)
3817 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
3819 __FILE__, __FUNCTION__, __LINE__);
3825 LOG2 (level, "CCC DEBUG NULL CONNECTION\n");
3829 LOG2 (level, "CCC DEBUG CONNECTION %s\n", GCC_2s (c));
3830 s = path_2s (c->path);
3831 LOG2 (level, "CCC path %s, own pos: %u\n", s, c->own_pos);
3833 LOG2 (level, "CCC state: %s, destroy: %u\n",
3834 GCC_state2s (c->state), c->destroy);
3835 LOG2 (level, "CCC pending messages: %u\n", c->pending_messages);
3836 if (NULL != c->perf)
3837 LOG2 (level, "CCC us/byte: %f\n", c->perf->avg);
3839 LOG2 (level, "CCC FWD flow control:\n");
3840 LOG2 (level, "CCC queue: %u/%u\n", c->fwd_fc.queue_n, c->fwd_fc.queue_max);
3841 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3842 c->fwd_fc.last_pid_sent, c->fwd_fc.last_pid_recv);
3843 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3844 c->fwd_fc.last_ack_sent, c->fwd_fc.last_ack_recv);
3845 LOG2 (level, "CCC recv PID bitmap: %X\n", c->fwd_fc.recv_bitmap);
3846 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3847 c->fwd_fc.poll_task, c->fwd_fc.poll_msg, c->fwd_fc.ack_msg);
3849 LOG2 (level, "CCC BCK flow control:\n");
3850 LOG2 (level, "CCC queue: %u/%u\n", c->bck_fc.queue_n, c->bck_fc.queue_max);
3851 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3852 c->bck_fc.last_pid_sent, c->bck_fc.last_pid_recv);
3853 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3854 c->bck_fc.last_ack_sent, c->bck_fc.last_ack_recv);
3855 LOG2 (level, "CCC recv PID bitmap: %X\n", c->bck_fc.recv_bitmap);
3856 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3857 c->bck_fc.poll_task, c->bck_fc.poll_msg, c->bck_fc.ack_msg);
3859 LOG2 (level, "CCC DEBUG CONNECTION END\n");