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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 * Handle for messages queued but not yet sent.
59 struct CadetConnectionQueue
62 struct CadetConnectionQueue *next;
63 struct CadetConnectionQueue *prev;
66 * Peer queue handle, to cancel if necessary.
68 struct CadetPeerQueue *peer_q;
71 * Continuation to call once sent.
76 * Closure for @e cont.
81 * Was this a forced message? (Do not account for it)
88 * Struct to encapsulate all the Flow Control information to a peer to which
89 * we are directly connected (on a core level).
91 struct CadetFlowControl
94 * Connection this controls.
96 struct CadetConnection *c;
98 struct CadetConnectionQueue *q_head;
99 struct CadetConnectionQueue *q_tail;
102 * How many messages are in the queue on this connection.
104 unsigned int queue_n;
107 * How many messages do we accept in the queue.
108 * If 0, the connection is broken in this direction (next hop disconnected).
110 unsigned int queue_max;
113 * ID of the next packet to send.
118 * ID of the last packet sent towards the peer.
120 uint32_t last_pid_sent;
123 * ID of the last packet received from the peer.
125 uint32_t last_pid_recv;
128 * Bitmap of past 32 messages received:
129 * - LSB being @c last_pid_recv.
130 * - MSB being @c last_pid_recv - 31 (mod UINTMAX).
132 uint32_t recv_bitmap;
135 * Last ACK sent to the peer (peer can't send more than this PID).
137 uint32_t last_ack_sent;
140 * Last ACK sent towards the origin (for traffic towards leaf node).
142 uint32_t last_ack_recv;
145 * Task to poll the peer in case of a lost ACK causes stall.
147 struct GNUNET_SCHEDULER_Task *poll_task;
150 * How frequently to poll for ACKs.
152 struct GNUNET_TIME_Relative poll_time;
155 * Queued poll message, to cancel if not necessary anymore (got ACK).
157 struct CadetConnectionQueue *poll_msg;
160 * Queued poll message, to cancel if not necessary anymore (got ACK).
162 struct CadetConnectionQueue *ack_msg;
166 * Keep a record of the last messages sent on this connection.
168 struct CadetConnectionPerformance
171 * Circular buffer for storing measurements.
173 double usecsperbyte[AVG_MSGS];
176 * Running average of @c usecsperbyte.
181 * How many values of @c usecsperbyte are valid.
186 * Index of the next "free" position in @c usecsperbyte.
193 * Struct containing all information regarding a connection to a peer.
195 struct CadetConnection
198 * Tunnel this connection is part of.
200 struct CadetTunnel *t;
203 * Flow control information for traffic fwd.
205 struct CadetFlowControl fwd_fc;
208 * Flow control information for traffic bck.
210 struct CadetFlowControl bck_fc;
213 * Measure connection performance on the endpoint.
215 struct CadetConnectionPerformance *perf;
218 * ID of the connection.
220 struct GNUNET_CADET_Hash id;
223 * Path being used for the tunnel. At the origin of the connection
224 * it's a pointer to the destination's path pool, otherwise just a copy.
226 struct CadetPeerPath *path;
229 * Task to keep the used paths alive at the owner,
230 * time tunnel out on all the other peers.
232 struct GNUNET_SCHEDULER_Task *fwd_maintenance_task;
235 * Task to keep the used paths alive at the destination,
236 * time tunnel out on all the other peers.
238 struct GNUNET_SCHEDULER_Task *bck_maintenance_task;
241 * Queue handle for maintainance traffic. One handle for FWD and BCK since
242 * one peer never needs to maintain both directions (no loopback connections).
244 struct CadetPeerQueue *maintenance_q;
247 * Should equal #get_next_hop(), or NULL if that peer disconnected.
249 struct CadetPeer *next_peer;
252 * Should equal #get_prev_hop(), or NULL if that peer disconnected.
254 struct CadetPeer *prev_peer;
257 * State of the connection.
259 enum CadetConnectionState state;
262 * Position of the local peer in the path.
264 unsigned int own_pos;
267 * Pending message count.
269 unsigned int pending_messages;
273 * - if 0, connection in use.
274 * - if 1, destroy on last message.
275 * - if 2, connection is being destroyed don't re-enter.
280 * In-connection-map flag. Sometimes, when @e destroy is set but
281 * actual destruction is delayed to enable us to finish processing
282 * queues (i.e. in the direction that is still working), we remove
283 * the connection from the map to prevent it from still being
284 * found (and used) by accident. This flag is set to #GNUNET_YES
285 * for a connection that is not in the #connections map. Should
286 * only be #GNUNET_YES if #destroy is also non-zero.
291 * Counter to do exponential backoff when creating a connection (max 64).
293 unsigned short create_retry;
296 * Task to check if connection has duplicates.
298 struct GNUNET_SCHEDULER_Task *check_duplicates_task;
302 /******************************************************************************/
303 /******************************* GLOBALS ***********************************/
304 /******************************************************************************/
307 * Global handle to the statistics service.
309 extern struct GNUNET_STATISTICS_Handle *stats;
312 * Local peer own ID (memory efficient handle).
314 extern GNUNET_PEER_Id myid;
317 * Local peer own ID (full value).
319 extern struct GNUNET_PeerIdentity my_full_id;
322 * Connections known, indexed by cid (CadetConnection).
324 static struct GNUNET_CONTAINER_MultiHashMap *connections;
327 * How many connections are we willing to maintain.
328 * Local connections are always allowed,
329 * even if there are more connections than max.
331 static unsigned long long max_connections;
334 * How many messages *in total* are we willing to queue, divide by number of
335 * connections to get connection queue size.
337 static unsigned long long max_msgs_queue;
340 * How often to send path keepalives. Paths timeout after 4 missed.
342 static struct GNUNET_TIME_Relative refresh_connection_time;
345 * How often to send path create / ACKs.
347 static struct GNUNET_TIME_Relative create_connection_time;
350 /******************************************************************************/
351 /******************************** STATIC ***********************************/
352 /******************************************************************************/
356 #if 0 // avoid compiler warning for unused static function
358 fc_debug (struct CadetFlowControl *fc)
360 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
361 fc->last_pid_recv, fc->last_ack_sent);
362 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
363 fc->last_pid_sent, fc->last_ack_recv);
364 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
365 fc->queue_n, fc->queue_max);
369 connection_debug (struct CadetConnection *c)
373 LOG (GNUNET_ERROR_TYPE_INFO, "DEBUG NULL CONNECTION\n");
376 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
377 peer2s (c->t->peer), GCC_2s (c));
378 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
379 c->state, c->pending_messages);
380 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
381 fc_debug (&c->fwd_fc);
382 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
383 fc_debug (&c->bck_fc);
389 * Schedule next keepalive task, taking in consideration
390 * the connection state and number of retries.
392 * @param c Connection for which to schedule the next keepalive.
393 * @param fwd Direction for the next keepalive.
396 schedule_next_keepalive (struct CadetConnection *c, int fwd);
400 * Resets the connection timeout task, some other message has done the
402 * - For the first peer on the direction this means to send
403 * a keepalive or a path confirmation message (either create or ACK).
404 * - For all other peers, this means to destroy the connection,
405 * due to lack of activity.
406 * Starts the timeout if no timeout was running (connection just created).
408 * @param c Connection whose timeout to reset.
409 * @param fwd Is this forward?
412 connection_reset_timeout (struct CadetConnection *c, int fwd);
416 * Get string description for tunnel state. Reentrant.
418 * @param s Tunnel state.
420 * @return String representation.
423 GCC_state2s (enum CadetConnectionState s)
427 case CADET_CONNECTION_NEW:
428 return "CADET_CONNECTION_NEW";
429 case CADET_CONNECTION_SENT:
430 return "CADET_CONNECTION_SENT";
431 case CADET_CONNECTION_ACK:
432 return "CADET_CONNECTION_ACK";
433 case CADET_CONNECTION_READY:
434 return "CADET_CONNECTION_READY";
435 case CADET_CONNECTION_DESTROYED:
436 return "CADET_CONNECTION_DESTROYED";
437 case CADET_CONNECTION_BROKEN:
438 return "CADET_CONNECTION_BROKEN";
441 LOG (GNUNET_ERROR_TYPE_ERROR, " conn state %u unknown!\n", s);
442 return "CADET_CONNECTION_STATE_ERROR";
448 * Initialize a Flow Control structure to the initial state.
450 * @param fc Flow Control structure to initialize.
453 fc_init (struct CadetFlowControl *fc)
455 fc->next_pid = (uint32_t) 0;
456 fc->last_pid_sent = (uint32_t) -1;
457 fc->last_pid_recv = (uint32_t) -1;
458 fc->last_ack_sent = (uint32_t) 0;
459 fc->last_ack_recv = (uint32_t) 0;
460 fc->poll_task = NULL;
461 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
463 fc->queue_max = (max_msgs_queue / max_connections) + 1;
470 * @param cid Connection ID.
472 * @return conntection with the given ID @cid or NULL if not found.
474 static struct CadetConnection *
475 connection_get (const struct GNUNET_CADET_Hash *cid)
477 return GNUNET_CONTAINER_multihashmap_get (connections, GC_h2hc (cid));
482 * Change the connection state. Cannot change a connection marked as destroyed.
484 * @param c Connection to change.
485 * @param state New state to set.
488 connection_change_state (struct CadetConnection* c,
489 enum CadetConnectionState state)
491 LOG (GNUNET_ERROR_TYPE_DEBUG,
492 "Connection %s state %s -> %s\n",
493 GCC_2s (c), GCC_state2s (c->state), GCC_state2s (state));
494 if (CADET_CONNECTION_DESTROYED <= c->state) /* Destroyed or broken. */
496 LOG (GNUNET_ERROR_TYPE_DEBUG, "state not changing anymore\n");
500 if (CADET_CONNECTION_READY == state)
506 * Mark a connection as "destroyed", to send all pending traffic and freeing
507 * all associated resources, without accepting new status changes on it.
509 * @param c Connection to mark as destroyed.
512 mark_destroyed (struct CadetConnection *c)
514 c->destroy = GNUNET_YES;
515 connection_change_state (c, CADET_CONNECTION_DESTROYED);
520 * Callback called when a queued ACK message is sent.
522 * @param cls Closure (FC).
523 * @param c Connection this message was on.
524 * @param q Queue handler this call invalidates.
525 * @param type Type of message sent.
526 * @param fwd Was this a FWD going message?
527 * @param size Size of the message.
531 struct CadetConnection *c,
532 struct CadetConnectionQueue *q,
533 uint16_t type, int fwd, size_t size)
535 struct CadetFlowControl *fc = cls;
542 * Send an ACK on the connection, informing the predecessor about
543 * the available buffer space. Should not be called in case the peer
544 * is origin (no predecessor) in the @c fwd direction.
546 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
547 * the ACK itself goes "back" (dest->root).
549 * @param c Connection on which to send the ACK.
550 * @param buffer How much space free to advertise?
551 * @param fwd Is this FWD ACK? (Going dest -> root)
552 * @param force Don't optimize out.
555 send_ack (struct CadetConnection *c, unsigned int buffer, int fwd, int force)
557 struct CadetFlowControl *next_fc;
558 struct CadetFlowControl *prev_fc;
559 struct GNUNET_CADET_ACK msg;
563 /* If origin, there is no connection to send ACKs. Wrong function! */
564 GCC_check_connections ();
565 if (GCC_is_origin (c, fwd))
567 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection %s is origin in %s\n",
568 GCC_2s (c), GC_f2s (fwd));
573 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
574 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
576 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection send %s ack on %s\n",
577 GC_f2s (fwd), GCC_2s (c));
579 /* Check if we need to transmit the ACK. */
580 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
581 if (3 < delta && buffer < delta && GNUNET_NO == force)
583 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
584 LOG (GNUNET_ERROR_TYPE_DEBUG,
585 " last pid recv: %u, last ack sent: %u\n",
586 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
587 GCC_check_connections ();
591 /* Ok, ACK might be necessary, what PID to ACK? */
592 ack = prev_fc->last_pid_recv + buffer;
593 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
594 LOG (GNUNET_ERROR_TYPE_DEBUG,
595 " last pid %u, last ack %u, qmax %u, q %u\n",
596 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
597 next_fc->queue_max, next_fc->queue_n);
598 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
600 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
601 GCC_check_connections ();
605 /* Check if message is already in queue */
606 if (NULL != prev_fc->ack_msg)
608 if (GC_is_pid_bigger (ack, prev_fc->last_ack_sent))
610 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
611 GCC_cancel (prev_fc->ack_msg);
612 /* GCC_cancel triggers ack_sent(), which clears fc->ack_msg */
616 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
617 GCC_check_connections ();
622 prev_fc->last_ack_sent = ack;
624 /* Build ACK message and send on conn */
625 msg.header.size = htons (sizeof (msg));
626 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_ACK);
627 msg.ack = htonl (ack);
630 prev_fc->ack_msg = GCC_send_prebuilt_message (&msg.header, UINT16_MAX, ack,
633 GNUNET_assert (NULL != prev_fc->ack_msg);
634 GCC_check_connections ();
639 * Update performance information if we are a connection's endpoint.
641 * @param c Connection to update.
642 * @param wait How much time did we wait to send the last message.
643 * @param size Size of the last message.
646 update_perf (struct CadetConnection *c,
647 struct GNUNET_TIME_Relative wait,
650 struct CadetConnectionPerformance *p;
654 return; /* Only endpoints are interested in timing. */
657 usecsperbyte = ((double) wait.rel_value_us) / size;
658 if (p->size == AVG_MSGS)
660 /* Array is full. Substract oldest value, add new one and store. */
661 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
662 p->usecsperbyte[p->idx] = usecsperbyte;
663 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
667 /* Array not yet full. Add current value to avg and store. */
668 p->usecsperbyte[p->idx] = usecsperbyte;
670 p->avg += p->usecsperbyte[p->idx];
674 p->idx = (p->idx + 1) % AVG_MSGS;
679 * Callback called when a connection queued message is sent.
681 * Calculates the average time and connection packet tracking.
683 * @param cls Closure (ConnectionQueue Handle), can be NULL.
684 * @param c Connection this message was on.
685 * @param fwd Was this a FWD going message?
686 * @param sent Was it really sent? (Could have been canceled)
687 * @param type Type of message sent.
688 * @param payload_type Type of payload, if applicable.
689 * @param pid Message ID, or 0 if not applicable (create, destroy, etc).
690 * @param size Size of the message.
691 * @param wait Time spent waiting for core (only the time for THIS message)
694 conn_message_sent (void *cls,
695 struct CadetConnection *c, int fwd, int sent,
696 uint16_t type, uint16_t payload_type, uint32_t pid,
698 struct GNUNET_TIME_Relative wait)
700 struct CadetConnectionQueue *q = cls;
701 struct CadetFlowControl *fc;
704 GCC_check_connections ();
705 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection message_sent\n");
707 /* If c is NULL, nothing to update. */
710 if (type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN
711 && type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY)
713 LOG (GNUNET_ERROR_TYPE_ERROR, "Message %s sent on NULL connection!\n",
716 GCC_check_connections ();
720 LOG (GNUNET_ERROR_TYPE_DEBUG, " %ssent %s %s pid %u\n",
721 sent ? "" : "not ", GC_f2s (fwd),
722 GC_m2s (type), GC_m2s (payload_type), pid);
723 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
725 /* Update flow control info. */
726 fc = fwd ? &c->fwd_fc : &c->bck_fc;
730 GNUNET_CONTAINER_DLL_remove (fc->q_head, fc->q_tail, q);
734 LOG (GNUNET_ERROR_TYPE_DEBUG, " calling cont\n");
735 q->cont (q->cont_cls, c, q, type, fwd, size);
739 else if (type == GNUNET_MESSAGE_TYPE_CADET_AX)
741 /* SHOULD NO LONGER HAPPEN FIXME: REMOVE CASE */
742 // If NULL == q and ENCRYPTED == type, message must have been ch_mngmnt
744 GNUNET_assert (0); // FIXME
746 else /* CONN_CREATE or CONN_ACK */
751 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P- %p %u\n", c, c->pending_messages);
752 c->pending_messages--;
753 if ( (GNUNET_YES == c->destroy) &&
754 (0 == c->pending_messages) )
756 LOG (GNUNET_ERROR_TYPE_DEBUG,
757 "! destroying connection!\n");
759 GCC_check_connections ();
763 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
766 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
767 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
768 c->maintenance_q = NULL;
769 /* Don't trigger a keepalive for sent ACKs, only SYN and SYNACKs */
770 if (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE == type || !fwd)
771 schedule_next_keepalive (c, fwd);
774 case GNUNET_MESSAGE_TYPE_CADET_AX:
775 if (GNUNET_YES == sent)
777 GNUNET_assert (NULL != q);
778 fc->last_pid_sent = pid;
779 if (GC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
780 GCC_start_poll (c, fwd);
781 GCC_send_ack (c, fwd, GNUNET_NO);
782 connection_reset_timeout (c, fwd);
785 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
786 if (GNUNET_NO == forced)
789 LOG (GNUNET_ERROR_TYPE_DEBUG,
790 "! accounting pid %u\n",
795 LOG (GNUNET_ERROR_TYPE_DEBUG,
796 "! forced, Q_N not accounting pid %u\n",
801 case GNUNET_MESSAGE_TYPE_CADET_KX:
802 if (GNUNET_YES == sent)
803 connection_reset_timeout (c, fwd);
806 case GNUNET_MESSAGE_TYPE_CADET_POLL:
810 case GNUNET_MESSAGE_TYPE_CADET_ACK:
814 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
815 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
819 LOG (GNUNET_ERROR_TYPE_ERROR, "%s unknown\n", GC_m2s (type));
823 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
825 update_perf (c, wait, size);
826 GCC_check_connections ();
831 * Get the previous hop in a connection
833 * @param c Connection.
835 * @return Previous peer in the connection.
837 static struct CadetPeer *
838 get_prev_hop (const struct CadetConnection *c)
844 LOG (GNUNET_ERROR_TYPE_DEBUG,
845 " get prev hop %s [%u/%u]\n",
846 GCC_2s (c), c->own_pos, c->path->length);
847 if (0 == c->own_pos || c->path->length < 2)
848 id = c->path->peers[0];
850 id = c->path->peers[c->own_pos - 1];
852 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
853 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
855 return GCP_get_short (id, GNUNET_YES);
860 * Get the next hop in a connection
862 * @param c Connection.
864 * @return Next peer in the connection.
866 static struct CadetPeer *
867 get_next_hop (const struct CadetConnection *c)
874 LOG (GNUNET_ERROR_TYPE_DEBUG, " get next hop %s [%u/%u]\n",
875 GCC_2s (c), c->own_pos, c->path->length);
876 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
877 id = c->path->peers[c->path->length - 1];
879 id = c->path->peers[c->own_pos + 1];
881 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
882 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
884 return GCP_get_short (id, GNUNET_YES);
889 * Check that the direct neighbours (previous and next hop)
890 * are properly associated with this connection.
892 * @param c connection to check
895 check_neighbours (const struct CadetConnection *c)
898 return; /* nothing to check */
899 GCP_check_connection (get_next_hop (c), c);
900 GCP_check_connection (get_prev_hop (c), c);
905 * Helper for #GCC_check_connections(). Calls #check_neighbours().
909 * @param value the `struct CadetConnection` to check
910 * @return #GNUNET_OK (continue to iterate)
913 check_connection (void *cls,
914 const struct GNUNET_HashCode *key,
917 struct CadetConnection *c = value;
919 check_neighbours (c);
925 * Check invariants for all connections using #check_neighbours().
928 GCC_check_connections ()
930 if (0 == CHECK_INVARIANTS)
932 if (NULL == connections)
934 GNUNET_CONTAINER_multihashmap_iterate (connections,
941 * Get the hop in a connection.
943 * @param c Connection.
944 * @param fwd Next in the FWD direction?
946 * @return Next peer in the connection.
948 static struct CadetPeer *
949 get_hop (struct CadetConnection *c, int fwd)
951 return (fwd) ? get_next_hop (c) : get_prev_hop (c);
956 * Get a bit mask for a message received out-of-order.
958 * @param last_pid_recv Last PID we received prior to the out-of-order.
959 * @param ooo_pid PID of the out-of-order message.
962 get_recv_bitmask (uint32_t last_pid_recv, uint32_t ooo_pid)
964 return 1 << (last_pid_recv - ooo_pid);
969 * Check is an out-of-order message is ok:
970 * - at most 31 messages behind.
973 * @param last_pid_recv Last in-order PID received.
976 is_ooo_ok (uint32_t last_pid_recv, uint32_t ooo_pid, uint32_t ooo_bitmap)
980 if (GC_is_pid_bigger (last_pid_recv - 31, ooo_pid))
983 mask = get_recv_bitmask (last_pid_recv, ooo_pid);
984 if (0 != (ooo_bitmap & mask))
992 * Is traffic coming from this sender 'FWD' traffic?
994 * @param c Connection to check.
995 * @param sender Short peer identity of neighbor.
997 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
998 * the traffic is 'FWD'.
999 * #GNUNET_NO for BCK.
1000 * #GNUNET_SYSERR for errors (sender isn't a hop in the connection).
1003 is_fwd (const struct CadetConnection *c,
1004 const struct CadetPeer *sender)
1008 id = GCP_get_short_id (sender);
1009 if (GCP_get_short_id (get_prev_hop (c)) == id)
1012 if (GCP_get_short_id (get_next_hop (c)) == id)
1015 return GNUNET_SYSERR;
1020 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
1021 * or a first CONNECTION_ACK directed to us.
1023 * @param c Connection to confirm.
1024 * @param fwd Should we send it FWD? (root->dest)
1025 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
1028 send_connection_ack (struct CadetConnection *c, int fwd)
1030 struct GNUNET_CADET_ConnectionACK msg;
1031 struct CadetTunnel *t;
1032 size_t size = sizeof (struct GNUNET_CADET_ConnectionACK);
1034 GCC_check_connections ();
1036 LOG (GNUNET_ERROR_TYPE_INFO,
1037 "==> { C %s ACK} %19s on conn %s (%p) %s [%5u]\n",
1038 GC_f2s (!fwd), "", GCC_2s (c), c, GC_f2s (fwd), size);
1040 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionACK));
1041 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK);
1042 msg.reserved = htonl (0);
1045 GNUNET_assert (NULL == c->maintenance_q);
1046 c->maintenance_q = GCP_send (get_hop (c, fwd), &msg.header,
1047 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK, 0,
1049 &conn_message_sent, NULL);
1050 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (conn`ACK)\n",
1051 c, c->pending_messages);
1052 c->pending_messages++;
1054 if (CADET_TUNNEL_NEW == GCT_get_cstate (t))
1055 GCT_change_cstate (t, CADET_TUNNEL_WAITING);
1056 if (CADET_CONNECTION_READY != c->state)
1057 connection_change_state (c, CADET_CONNECTION_SENT);
1058 GCC_check_connections ();
1063 * Send a notification that a connection is broken.
1065 * @param c Connection that is broken.
1066 * @param id1 Peer that has disconnected.
1067 * @param id2 Peer that has disconnected.
1068 * @param fwd Direction towards which to send it.
1071 send_broken (struct CadetConnection *c,
1072 const struct GNUNET_PeerIdentity *id1,
1073 const struct GNUNET_PeerIdentity *id2,
1076 struct GNUNET_CADET_ConnectionBroken msg;
1078 GCC_check_connections ();
1079 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1080 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1084 GNUNET_assert (NULL ==
1085 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, 0, c, fwd,
1086 GNUNET_YES, NULL, NULL));
1087 GCC_check_connections ();
1092 * Send a notification that a connection is broken, when a connection
1093 * isn't even known to the local peer or soon to be destroyed.
1095 * @param connection_id Connection ID.
1096 * @param id1 Peer that has disconnected, probably local peer.
1097 * @param id2 Peer that has disconnected can be NULL if unknown.
1098 * @param neighbor Peer to notify (neighbor who sent the connection).
1101 send_broken_unknown (const struct GNUNET_CADET_Hash *connection_id,
1102 const struct GNUNET_PeerIdentity *id1,
1103 const struct GNUNET_PeerIdentity *id2,
1104 struct CadetPeer *neighbor)
1106 struct GNUNET_CADET_ConnectionBroken msg;
1108 GCC_check_connections ();
1109 LOG (GNUNET_ERROR_TYPE_INFO, "--> BROKEN on unknown connection %s\n",
1110 GNUNET_h2s (GC_h2hc (connection_id)));
1112 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1113 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1114 msg.cid = *connection_id;
1119 memset (&msg.peer2, 0, sizeof (msg.peer2));
1120 GNUNET_assert (NULL != GCP_send (neighbor, &msg.header,
1122 NULL, GNUNET_SYSERR, /* connection, fwd */
1123 NULL, NULL)); /* continuation */
1124 GCC_check_connections ();
1129 * Send keepalive packets for a connection.
1131 * @param c Connection to keep alive..
1132 * @param fwd Is this a FWD keepalive? (owner -> dest).
1135 send_connection_keepalive (struct CadetConnection *c, int fwd)
1137 struct GNUNET_MessageHeader msg;
1138 struct CadetFlowControl *fc;
1141 GCC_check_connections ();
1142 LOG (GNUNET_ERROR_TYPE_INFO,
1143 "keepalive %s for connection %s\n",
1144 GC_f2s (fwd), GCC_2s (c));
1146 GNUNET_assert (NULL != c->t);
1147 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1148 tunnel_ready = GNUNET_YES == GCT_has_queued_traffic (c->t)
1149 && CADET_TUNNEL_KEY_OK <= GCT_get_estate (c->t);
1150 if (0 < fc->queue_n || tunnel_ready)
1152 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, traffic in queue\n");
1156 GNUNET_STATISTICS_update (stats, "# keepalives sent", 1, GNUNET_NO);
1158 GNUNET_assert (NULL != c->t);
1159 msg.size = htons (sizeof (msg));
1160 msg.type = htons (GNUNET_MESSAGE_TYPE_CADET_KEEPALIVE);
1162 GNUNET_assert (NULL ==
1163 GCT_send_prebuilt_message (&msg, c->t, c,
1164 GNUNET_NO, NULL, NULL));
1165 GCC_check_connections ();
1170 * Send CONNECTION_{CREATE/ACK} packets for a connection.
1172 * @param c Connection for which to send the message.
1173 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
1176 connection_recreate (struct CadetConnection *c, int fwd)
1178 LOG (GNUNET_ERROR_TYPE_DEBUG,
1179 "sending connection recreate\n");
1181 GCC_send_create (c);
1183 send_connection_ack (c, GNUNET_NO);
1188 * Generic connection timer management.
1189 * Depending on the role of the peer in the connection will send the
1190 * appropriate message (build or keepalive)
1192 * @param c Conncetion to maintain.
1193 * @param fwd Is FWD?
1196 connection_maintain (struct CadetConnection *c, int fwd)
1198 if (GNUNET_NO != c->destroy)
1200 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, being destroyed\n");
1207 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1211 if (CADET_TUNNEL_SEARCHING == GCT_get_cstate (c->t))
1213 /* If status is SEARCHING, why is there a connection? Should be WAITING */
1215 GCT_debug (c->t, GNUNET_ERROR_TYPE_ERROR);
1216 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, tunnel SEARCHING\n");
1217 schedule_next_keepalive (c, fwd);
1222 case CADET_CONNECTION_NEW:
1225 case CADET_CONNECTION_SENT:
1226 connection_recreate (c, fwd);
1228 case CADET_CONNECTION_READY:
1229 send_connection_keepalive (c, fwd);
1238 * Keep the connection alive.
1240 * @param c Connection to keep alive.
1241 * @param fwd Direction.
1244 connection_keepalive (struct CadetConnection *c,
1247 GCC_check_connections ();
1248 LOG (GNUNET_ERROR_TYPE_DEBUG,
1249 "%s keepalive for %s\n",
1250 GC_f2s (fwd), GCC_2s (c));
1253 c->fwd_maintenance_task = NULL;
1255 c->bck_maintenance_task = NULL;
1256 connection_maintain (c, fwd);
1257 GCC_check_connections ();
1258 /* Next execution will be scheduled by message_sent or _maintain*/
1263 * Keep the connection alive in the FWD direction.
1265 * @param cls Closure (connection to keepalive).
1268 connection_fwd_keepalive (void *cls)
1270 struct CadetConnection *c = cls;
1272 GCC_check_connections ();
1273 connection_keepalive (c,
1275 GCC_check_connections ();
1280 * Keep the connection alive in the BCK direction.
1282 * @param cls Closure (connection to keepalive).
1285 connection_bck_keepalive (void *cls)
1287 struct CadetConnection *c = cls;
1289 GCC_check_connections ();
1290 connection_keepalive (c,
1292 GCC_check_connections ();
1297 * Schedule next keepalive task, taking in consideration
1298 * the connection state and number of retries.
1300 * If the peer is not the origin, do nothing.
1302 * @param c Connection for which to schedule the next keepalive.
1303 * @param fwd Direction for the next keepalive.
1306 schedule_next_keepalive (struct CadetConnection *c, int fwd)
1308 struct GNUNET_TIME_Relative delay;
1309 struct GNUNET_SCHEDULER_Task * *task_id;
1310 GNUNET_SCHEDULER_TaskCallback keepalive_task;
1312 GCC_check_connections ();
1313 if (GNUNET_NO == GCC_is_origin (c, fwd))
1316 /* Calculate delay to use, depending on the state of the connection */
1317 if (CADET_CONNECTION_READY == c->state)
1319 delay = refresh_connection_time;
1323 if (1 > c->create_retry)
1324 c->create_retry = 1;
1325 delay = GNUNET_TIME_relative_multiply (create_connection_time,
1327 if (c->create_retry < 64) // TODO make configurable
1328 c->create_retry *= 2;
1331 /* Select direction-dependent parameters */
1332 if (GNUNET_YES == fwd)
1334 task_id = &c->fwd_maintenance_task;
1335 keepalive_task = &connection_fwd_keepalive;
1339 task_id = &c->bck_maintenance_task;
1340 keepalive_task = &connection_bck_keepalive;
1343 /* Check that no one scheduled it before us */
1344 if (NULL != *task_id)
1346 /* No need for a _break. It can happen for instance when sending a SYNACK
1347 * for a duplicate SYN: the first SYNACK scheduled the task. */
1348 GNUNET_SCHEDULER_cancel (*task_id);
1351 /* Schedule the task */
1352 *task_id = GNUNET_SCHEDULER_add_delayed (delay,
1355 LOG (GNUNET_ERROR_TYPE_DEBUG,
1356 "next keepalive in %s\n",
1357 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1358 GCC_check_connections ();
1363 * Cancel all transmissions that belong to a certain connection.
1365 * If the connection is scheduled for destruction and no more messages are left,
1366 * the connection will be destroyed by the continuation call.
1368 * @param c Connection which to cancel. Might be destroyed during this call.
1369 * @param fwd Cancel fwd traffic?
1372 connection_cancel_queues (struct CadetConnection *c,
1375 struct CadetFlowControl *fc;
1377 GCC_check_connections ();
1378 LOG (GNUNET_ERROR_TYPE_DEBUG,
1379 "Cancel %s queues for connection %s\n",
1380 GC_f2s (fwd), GCC_2s (c));
1387 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1388 if (NULL != fc->poll_task)
1390 GNUNET_SCHEDULER_cancel (fc->poll_task);
1391 fc->poll_task = NULL;
1392 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL task for fc %p\n", fc);
1394 if (NULL != fc->poll_msg)
1396 GCC_cancel (fc->poll_msg);
1397 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL msg for fc %p\n", fc);
1400 while (NULL != fc->q_head)
1402 GCC_cancel (fc->q_head);
1404 GCC_check_connections ();
1409 * Function called if a connection has been stalled for a while,
1410 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1412 * @param cls Closure (poll ctx).
1415 connection_poll (void *cls);
1419 * Callback called when a queued POLL message is sent.
1421 * @param cls Closure (flow control context).
1422 * @param c Connection this message was on.
1423 * @param q Queue handler this call invalidates.
1424 * @param type Type of message sent.
1425 * @param fwd Was this a FWD going message?
1426 * @param size Size of the message.
1429 poll_sent (void *cls,
1430 struct CadetConnection *c,
1431 struct CadetConnectionQueue *q,
1432 uint16_t type, int fwd, size_t size)
1434 struct CadetFlowControl *fc = cls;
1436 GNUNET_assert (fc->poll_msg == q);
1437 fc->poll_msg = NULL;
1438 if (2 == c->destroy)
1440 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL canceled on shutdown\n");
1443 if (0 == fc->queue_max)
1445 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL cancelled: neighbor disconnected\n");
1448 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL sent for %s, scheduling new one!\n",
1450 GNUNET_assert (NULL == fc->poll_task);
1451 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1452 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1455 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1460 * Function called if a connection has been stalled for a while,
1461 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1463 * @param cls Closure (poll ctx).
1466 connection_poll (void *cls)
1468 struct CadetFlowControl *fc = cls;
1469 struct GNUNET_CADET_Poll msg;
1470 struct CadetConnection *c;
1473 fc->poll_task = NULL;
1474 GCC_check_connections ();
1476 fwd = fc == &c->fwd_fc;
1477 LOG (GNUNET_ERROR_TYPE_DEBUG, "Polling connection %s %s\n",
1478 GCC_2s (c), GC_f2s (fwd));
1480 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_POLL);
1481 msg.header.size = htons (sizeof (msg));
1482 msg.pid = htonl (fc->last_pid_sent);
1483 LOG (GNUNET_ERROR_TYPE_DEBUG, " last pid sent: %u\n", fc->last_pid_sent);
1485 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, fc->last_pid_sent, c,
1486 fc == &c->fwd_fc, GNUNET_YES, &poll_sent, fc);
1487 GNUNET_assert (NULL != fc->poll_msg);
1488 GCC_check_connections ();
1493 * Generic connection timeout implementation.
1495 * Timeout function due to lack of keepalive/traffic from an endpoint.
1496 * Destroys connection if called.
1498 * @param c Connection to destroy.
1499 * @param fwd Was the timeout from the origin? (FWD timeout)
1502 connection_timeout (struct CadetConnection *c, int fwd)
1504 GCC_check_connections ();
1506 LOG (GNUNET_ERROR_TYPE_INFO,
1507 "Connection %s %s timed out. Destroying.\n",
1510 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1512 if (GCC_is_origin (c, fwd)) /* Loopback? Something is wrong! */
1518 /* If dest, send "broken" notification. */
1519 if (GCC_is_terminal (c, fwd))
1521 struct CadetPeer *next_hop;
1523 next_hop = fwd ? get_prev_hop (c) : get_next_hop (c);
1524 send_broken_unknown (&c->id, &my_full_id, NULL, next_hop);
1528 GCC_check_connections ();
1533 * Timeout function due to lack of keepalive/traffic from the owner.
1534 * Destroys connection if called.
1536 * @param cls Closure (connection to destroy).
1539 connection_fwd_timeout (void *cls)
1541 struct CadetConnection *c = cls;
1543 c->fwd_maintenance_task = NULL;
1544 GCC_check_connections ();
1545 connection_timeout (c, GNUNET_YES);
1546 GCC_check_connections ();
1551 * Timeout function due to lack of keepalive/traffic from the destination.
1552 * Destroys connection if called.
1554 * @param cls Closure (connection to destroy).
1557 connection_bck_timeout (void *cls)
1559 struct CadetConnection *c = cls;
1561 c->bck_maintenance_task = NULL;
1562 GCC_check_connections ();
1563 connection_timeout (c, GNUNET_NO);
1564 GCC_check_connections ();
1569 * Resets the connection timeout task, some other message has done the
1571 * - For the first peer on the direction this means to send
1572 * a keepalive or a path confirmation message (either create or ACK).
1573 * - For all other peers, this means to destroy the connection,
1574 * due to lack of activity.
1575 * Starts the timeout if no timeout was running (connection just created).
1577 * @param c Connection whose timeout to reset.
1578 * @param fwd Is this forward?
1580 * TODO use heap to improve efficiency of scheduler.
1583 connection_reset_timeout (struct CadetConnection *c, int fwd)
1585 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1586 if (GCC_is_origin (c, fwd)) /* Startpoint */
1588 schedule_next_keepalive (c, fwd);
1589 if (NULL != c->maintenance_q)
1591 GCP_send_cancel (c->maintenance_q);
1592 c->maintenance_q = NULL; /* Is set to NULL by conn_message_sent anyway */
1595 else /* Relay, endpoint. */
1597 struct GNUNET_TIME_Relative delay;
1598 struct GNUNET_SCHEDULER_Task * *ti;
1599 GNUNET_SCHEDULER_TaskCallback f;
1601 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1604 GNUNET_SCHEDULER_cancel (*ti);
1605 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1606 LOG (GNUNET_ERROR_TYPE_DEBUG,
1607 " timing out in %s\n",
1608 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_NO));
1609 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1610 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1616 * Iterator to compare each connection's path with the path of a new connection.
1618 * If the connection coincides, the c member of path is set to the connection
1619 * and the destroy flag of the connection is set.
1621 * @param cls Closure (new path).
1622 * @param c Connection in the tunnel to check.
1625 check_path (void *cls, struct CadetConnection *c)
1627 struct CadetConnection *new_conn = cls;
1628 struct CadetPeerPath *path = new_conn->path;
1630 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking %s (%p), length %u\n",
1631 GCC_2s (c), c, c->path->length);
1634 && GNUNET_NO == c->destroy
1635 && CADET_CONNECTION_BROKEN != c->state
1636 && CADET_CONNECTION_DESTROYED != c->state
1637 && path_equivalent (path, c->path))
1639 new_conn->destroy = GNUNET_YES; /* Do not mark_destroyed, */
1640 new_conn->path->c = c; /* this is only a flag for the Iterator. */
1641 LOG (GNUNET_ERROR_TYPE_DEBUG, " MATCH!\n");
1647 * Finds out if this path is already being used by an existing connection.
1649 * Checks the tunnel towards the destination to see if it contains
1650 * any connection with the same path.
1652 * If the existing connection is ready, it is kept.
1653 * Otherwise if the sender has a smaller ID that ours, we accept it (and
1654 * the peer will eventually reject our attempt).
1656 * @param path Path to check.
1657 * @return #GNUNET_YES if the tunnel has a connection with the same path,
1658 * #GNUNET_NO otherwise.
1661 does_connection_exist (struct CadetConnection *conn)
1663 struct CadetPeer *p;
1664 struct CadetTunnel *t;
1665 struct CadetConnection *c;
1667 p = GCP_get_short (conn->path->peers[0], GNUNET_NO);
1670 t = GCP_get_tunnel (p);
1674 LOG (GNUNET_ERROR_TYPE_DEBUG, "Checking for duplicates\n");
1676 GCT_iterate_connections (t, &check_path, conn);
1678 if (GNUNET_YES == conn->destroy)
1681 conn->destroy = GNUNET_NO;
1682 conn->path->c = conn;
1683 LOG (GNUNET_ERROR_TYPE_DEBUG, " found duplicate of %s\n", GCC_2s (conn));
1684 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate: %s\n", GCC_2s (c));
1685 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1686 if (CADET_CONNECTION_READY == c->state)
1688 /* The other peer confirmed a live connection with this path,
1689 * why are they trying to duplicate it? */
1690 GNUNET_STATISTICS_update (stats, "# duplicate connections", 1, GNUNET_NO);
1693 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate not ready, connection unique\n");
1698 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s has no duplicates\n", GCC_2s (conn));
1705 * @brief Check if the tunnel this connection belongs to has any other
1706 * connection with the same path, and destroy one if so.
1708 * @param cls Closure (connection to check).
1711 check_duplicates (void *cls)
1713 struct CadetConnection *c = cls;
1715 c->check_duplicates_task = NULL;
1716 if (GNUNET_YES == does_connection_exist (c))
1718 GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1719 send_broken (c, &my_full_id, &my_full_id, GCC_is_origin (c, GNUNET_YES));
1726 * Wait for enough time to let any dead connections time out and check for
1727 * any remaining duplicates.
1729 * @param c Connection that is a potential duplicate.
1732 schedule_check_duplicates (struct CadetConnection *c)
1734 struct GNUNET_TIME_Relative delay;
1736 if (NULL != c->check_duplicates_task)
1738 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 5);
1739 c->check_duplicates_task = GNUNET_SCHEDULER_add_delayed (delay,
1746 * Add the connection to the list of both neighbors.
1748 * @param c Connection.
1750 * @return #GNUNET_OK if everything went fine
1751 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1754 register_neighbors (struct CadetConnection *c)
1756 c->next_peer = get_next_hop (c);
1757 c->prev_peer = get_prev_hop (c);
1758 GNUNET_assert (c->next_peer != c->prev_peer);
1759 LOG (GNUNET_ERROR_TYPE_DEBUG,
1760 "register neighbors for connection %s\n",
1762 path_debug (c->path);
1763 LOG (GNUNET_ERROR_TYPE_DEBUG,
1764 "own pos %u\n", c->own_pos);
1765 LOG (GNUNET_ERROR_TYPE_DEBUG,
1766 "putting connection %s to next peer %p\n",
1769 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n",
1771 GCP_2s (c->next_peer));
1772 LOG (GNUNET_ERROR_TYPE_DEBUG,
1773 "putting connection %s to prev peer %p\n",
1776 LOG (GNUNET_ERROR_TYPE_DEBUG,
1777 "prev peer %p %s\n",
1779 GCP_2s (c->prev_peer));
1781 if ( (GNUNET_NO == GCP_is_neighbor (c->next_peer)) ||
1782 (GNUNET_NO == GCP_is_neighbor (c->prev_peer)) )
1784 if (GCC_is_origin (c, GNUNET_YES))
1785 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1786 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1788 LOG (GNUNET_ERROR_TYPE_DEBUG,
1789 " register neighbors failed\n");
1790 LOG (GNUNET_ERROR_TYPE_DEBUG,
1791 " prev: %s, neighbor?: %d\n",
1792 GCP_2s (c->prev_peer),
1793 GCP_is_neighbor (c->prev_peer));
1794 LOG (GNUNET_ERROR_TYPE_DEBUG,
1795 " next: %s, neighbor?: %d\n",
1796 GCP_2s (c->next_peer),
1797 GCP_is_neighbor (c->next_peer));
1798 return GNUNET_SYSERR;
1800 GCP_add_connection (c->next_peer, c, GNUNET_NO);
1801 GCP_add_connection (c->prev_peer, c, GNUNET_YES);
1808 * Remove the connection from the list of both neighbors.
1810 * @param c Connection.
1813 unregister_neighbors (struct CadetConnection *c)
1815 // struct CadetPeer *peer; FIXME dont use next_peer, prev_peer
1816 /* Either already unregistered or never got registered, it's ok either way. */
1817 if (NULL == c->path)
1819 if (NULL != c->next_peer)
1821 GCP_remove_connection (c->next_peer, c);
1822 c->next_peer = NULL;
1824 if (NULL != c->prev_peer)
1826 GCP_remove_connection (c->prev_peer, c);
1827 c->prev_peer = NULL;
1833 * Invalidates all paths towards all peers that comprise the connection which
1834 * rely on the disconnected peer.
1836 * ~O(n^3) (peers in connection * paths/peer * links/path)
1838 * @param c Connection whose peers' paths to clean.
1839 * @param disconnected Peer that disconnected.
1842 invalidate_paths (struct CadetConnection *c,
1843 struct CadetPeer *disconnected)
1845 struct CadetPeer *peer;
1848 for (i = 0; i < c->path->length; i++)
1850 peer = GCP_get_short (c->path->peers[i], GNUNET_NO);
1852 GCP_notify_broken_link (peer, &my_full_id, GCP_get_id (disconnected));
1858 * Bind the connection to the peer and the tunnel to that peer.
1860 * If the peer has no tunnel, create one. Update tunnel and connection
1861 * data structres to reflect new status.
1863 * @param c Connection.
1867 add_to_peer (struct CadetConnection *c,
1868 struct CadetPeer *peer)
1870 GCP_add_tunnel (peer);
1871 c->t = GCP_get_tunnel (peer);
1872 GCT_add_connection (c->t, c);
1877 * Log receipt of message on stderr (INFO level).
1879 * @param message Message received.
1880 * @param peer Peer who sent the message.
1881 * @param conn_id Connection ID of the message.
1884 log_message (const struct GNUNET_MessageHeader *message,
1885 const struct CadetPeer *peer,
1886 const struct GNUNET_CADET_Hash *conn_id)
1892 size = ntohs (message->size);
1893 type = ntohs (message->type);
1896 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
1897 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
1898 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
1899 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
1905 LOG (GNUNET_ERROR_TYPE_INFO, "<%s %s on conn %s from %s, %6u bytes\n",
1906 arrow, GC_m2s (type), GNUNET_h2s (GC_h2hc (conn_id)),
1907 GCP_2s(peer), (unsigned int) size);
1910 /******************************************************************************/
1911 /******************************** API ***********************************/
1912 /******************************************************************************/
1915 * Handler for connection creation.
1917 * @param peer Message sender (neighbor).
1918 * @param msg Message itself.
1921 GCC_handle_create (struct CadetPeer *peer,
1922 const struct GNUNET_CADET_ConnectionCreate *msg)
1924 const struct GNUNET_CADET_Hash *cid;
1925 struct GNUNET_PeerIdentity *id;
1926 struct CadetPeerPath *path;
1927 struct CadetPeer *dest_peer;
1928 struct CadetPeer *orig_peer;
1929 struct CadetConnection *c;
1930 unsigned int own_pos;
1933 GCC_check_connections ();
1934 size = ntohs (msg->header.size);
1936 /* Calculate hops */
1937 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
1938 if (0 != size % sizeof (struct GNUNET_PeerIdentity))
1940 GNUNET_break_op (0);
1943 size /= sizeof (struct GNUNET_PeerIdentity);
1946 GNUNET_break_op (0);
1949 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1951 /* Get parameters */
1953 log_message (&msg->header, peer, cid);
1954 id = (struct GNUNET_PeerIdentity *) &msg[1];
1955 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
1957 /* Create connection */
1958 c = connection_get (cid);
1961 path = path_build_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
1962 size, myid, &own_pos);
1965 /* Path was malformed, probably our own ID was not in it. */
1966 GNUNET_STATISTICS_update (stats, "# malformed paths", 1, GNUNET_NO);
1967 GNUNET_break_op (0);
1972 /* We received this request from a neighbor, we cannot be origin */
1973 GNUNET_STATISTICS_update (stats, "# fake paths", 1, GNUNET_NO);
1974 GNUNET_break_op (0);
1975 path_destroy (path);
1979 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1980 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1981 c = GCC_new (cid, NULL, path, own_pos);
1984 if (path->length - 1 == own_pos)
1986 /* If we are destination, why did the creation fail? */
1988 path_destroy (path);
1989 GCC_check_connections ();
1992 send_broken_unknown (cid, &my_full_id,
1993 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
1995 path_destroy (path);
1996 GCC_check_connections ();
1999 GCP_add_path_to_all (path, GNUNET_NO);
2000 connection_reset_timeout (c, GNUNET_YES);
2004 path = path_duplicate (c->path);
2006 if (CADET_CONNECTION_NEW == c->state)
2007 connection_change_state (c, CADET_CONNECTION_SENT);
2009 /* Remember peers */
2010 dest_peer = GCP_get (&id[size - 1], GNUNET_YES);
2011 orig_peer = GCP_get (&id[0], GNUNET_YES);
2013 /* Is it a connection to us? */
2014 if (c->own_pos == path->length - 1)
2016 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
2017 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
2019 add_to_peer (c, orig_peer);
2020 if (GNUNET_YES == does_connection_exist (c))
2022 /* Peer created a connection equal to one we think exists
2024 * Solution: Keep both and postpone disambiguation. In the meantime
2025 * the connection will time out or peer will inform us it is broken.
2028 * - Use explicit duplicate.
2029 * - Accept new conn and destroy the old. (interruption in higher level)
2030 * - Keep the one with higher ID / created by peer with higher ID. */
2031 schedule_check_duplicates (c);
2034 if (CADET_TUNNEL_NEW == GCT_get_cstate (c->t))
2035 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
2037 send_connection_ack (c, GNUNET_NO);
2038 if (CADET_CONNECTION_SENT == c->state)
2039 connection_change_state (c, CADET_CONNECTION_ACK);
2043 /* It's for somebody else! Retransmit. */
2044 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
2045 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
2046 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
2047 GNUNET_assert (NULL ==
2048 GCC_send_prebuilt_message (&msg->header, 0, 0, c,
2049 GNUNET_YES, GNUNET_YES,
2052 path_destroy (path);
2053 GCC_check_connections ();
2058 * Handler for connection confirmations.
2060 * @param peer Message sender (neighbor).
2061 * @param msg Message itself.
2064 GCC_handle_confirm (struct CadetPeer *peer,
2065 const struct GNUNET_CADET_ConnectionACK *msg)
2067 struct CadetConnection *c;
2068 enum CadetConnectionState oldstate;
2071 GCC_check_connections ();
2072 log_message (&msg->header, peer, &msg->cid);
2073 c = connection_get (&msg->cid);
2076 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
2078 LOG (GNUNET_ERROR_TYPE_DEBUG,
2079 " don't know the connection!\n");
2080 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2081 GCC_check_connections ();
2084 if (GNUNET_NO != c->destroy)
2086 GNUNET_assert (CADET_CONNECTION_DESTROYED == c->state);
2087 GNUNET_STATISTICS_update (stats, "# control on dying connection",
2089 LOG (GNUNET_ERROR_TYPE_DEBUG,
2090 "connection %s being destroyed, ignoring confirm\n",
2092 GCC_check_connections ();
2096 oldstate = c->state;
2097 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GCP_2s (peer));
2098 if (get_next_hop (c) == peer)
2100 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
2102 if (CADET_CONNECTION_SENT == oldstate)
2103 connection_change_state (c, CADET_CONNECTION_ACK);
2105 else if (get_prev_hop (c) == peer)
2107 LOG (GNUNET_ERROR_TYPE_DEBUG, " FINAL ACK\n");
2109 connection_change_state (c, CADET_CONNECTION_READY);
2113 GNUNET_STATISTICS_update (stats, "# control on connection from wrong peer",
2115 GNUNET_break_op (0);
2119 connection_reset_timeout (c, fwd);
2121 /* Add path to peers? */
2122 if (NULL != c->path)
2124 GCP_add_path_to_all (c->path, GNUNET_YES);
2131 /* Message for us as creator? */
2132 if (GNUNET_YES == GCC_is_origin (c, GNUNET_YES))
2134 if (GNUNET_NO != fwd)
2139 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
2141 /* If just created, cancel the short timeout and start a long one */
2142 if (CADET_CONNECTION_SENT == oldstate)
2143 connection_reset_timeout (c, GNUNET_YES);
2145 /* Change connection state, send ACK */
2146 connection_change_state (c, CADET_CONNECTION_READY);
2147 send_connection_ack (c, GNUNET_YES);
2149 /* Change tunnel state, trigger KX */
2150 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2151 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2152 GCC_check_connections ();
2156 /* Message for us as destination? */
2157 if (GCC_is_terminal (c, GNUNET_YES))
2159 if (GNUNET_YES != fwd)
2164 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
2166 /* If just created, cancel the short timeout and start a long one */
2167 if (CADET_CONNECTION_ACK == oldstate)
2168 connection_reset_timeout (c, GNUNET_NO);
2170 /* Change tunnel state */
2171 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2172 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2173 GCC_check_connections ();
2177 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2178 GNUNET_assert (NULL ==
2179 GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2180 GNUNET_YES, NULL, NULL));
2181 GCC_check_connections ();
2187 * Handler for notifications of broken connections.
2189 * @param peer Message sender (neighbor).
2190 * @param msg Message itself.
2193 GCC_handle_broken (struct CadetPeer *peer,
2194 const struct GNUNET_CADET_ConnectionBroken *msg)
2196 struct CadetConnection *c;
2197 struct CadetTunnel *t;
2200 GCC_check_connections ();
2201 log_message (&msg->header, peer, &msg->cid);
2202 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2203 GNUNET_i2s (&msg->peer1));
2204 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2205 GNUNET_i2s (&msg->peer2));
2206 c = connection_get (&msg->cid);
2209 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
2210 GNUNET_STATISTICS_update (stats, "# duplicate CONNECTION_BROKEN",
2212 GCC_check_connections ();
2218 fwd = is_fwd (c, peer);
2219 if (GNUNET_SYSERR == fwd)
2221 GNUNET_break_op (0);
2222 GCC_check_connections ();
2226 if (GCC_is_terminal (c, fwd))
2228 struct CadetPeer *endpoint;
2232 /* A terminal connection should not have 't' set to NULL. */
2234 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
2237 endpoint = GCP_get_short (c->path->peers[c->path->length - 1], GNUNET_YES);
2238 if (2 < c->path->length)
2239 path_invalidate (c->path);
2240 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
2242 connection_change_state (c, CADET_CONNECTION_BROKEN);
2243 GCT_remove_connection (t, c);
2250 GNUNET_assert (NULL ==
2251 GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2252 GNUNET_YES, NULL, NULL));
2253 connection_cancel_queues (c, !fwd);
2255 GCC_check_connections ();
2261 * Handler for notifications of destroyed connections.
2263 * @param peer Message sender (neighbor).
2264 * @param msg Message itself.
2267 GCC_handle_destroy (struct CadetPeer *peer,
2268 const struct GNUNET_CADET_ConnectionDestroy *msg)
2270 struct CadetConnection *c;
2273 GCC_check_connections ();
2274 log_message (&msg->header, peer, &msg->cid);
2275 c = connection_get (&msg->cid);
2278 /* Probably already got the message from another path,
2279 * destroyed the tunnel and retransmitted to children.
2282 GNUNET_STATISTICS_update (stats,
2283 "# control on unknown connection",
2285 LOG (GNUNET_ERROR_TYPE_DEBUG,
2286 " connection unknown destroyed: previously destroyed?\n");
2287 GCC_check_connections ();
2291 fwd = is_fwd (c, peer);
2292 if (GNUNET_SYSERR == fwd)
2294 GNUNET_break_op (0);
2295 GCC_check_connections ();
2299 if (GNUNET_NO == GCC_is_terminal (c, fwd))
2301 GNUNET_assert (NULL ==
2302 GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2303 GNUNET_YES, NULL, NULL));
2305 else if (0 == c->pending_messages)
2307 LOG (GNUNET_ERROR_TYPE_DEBUG, " directly destroying connection!\n");
2309 GCC_check_connections ();
2315 GCT_remove_connection (c->t, c);
2318 GCC_check_connections ();
2324 * Handler for cadet network traffic hop-by-hop acks.
2326 * @param peer Message sender (neighbor).
2327 * @param msg Message itself.
2330 GCC_handle_ack (struct CadetPeer *peer,
2331 const struct GNUNET_CADET_ACK *msg)
2333 struct CadetConnection *c;
2334 struct CadetFlowControl *fc;
2338 GCC_check_connections ();
2339 log_message (&msg->header, peer, &msg->cid);
2340 c = connection_get (&msg->cid);
2343 GNUNET_STATISTICS_update (stats,
2344 "# ack on unknown connection",
2347 send_broken_unknown (&msg->cid,
2351 GCC_check_connections ();
2355 /* Is this a forward or backward ACK? */
2356 if (get_next_hop (c) == peer)
2361 else if (get_prev_hop (c) == peer)
2368 GNUNET_break_op (0);
2372 ack = ntohl (msg->ack);
2373 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s ACK %u (was %u)\n",
2374 GC_f2s (fwd), ack, fc->last_ack_recv);
2375 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2376 fc->last_ack_recv = ack;
2378 /* Cancel polling if the ACK is big enough. */
2379 if (NULL != fc->poll_task &&
2380 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2382 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2383 GNUNET_SCHEDULER_cancel (fc->poll_task);
2384 fc->poll_task = NULL;
2385 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2388 GCC_check_connections ();
2393 * Handler for cadet network traffic hop-by-hop data counter polls.
2395 * @param peer Message sender (neighbor).
2396 * @param msg Message itself.
2399 GCC_handle_poll (struct CadetPeer *peer,
2400 const struct GNUNET_CADET_Poll *msg)
2402 struct CadetConnection *c;
2403 struct CadetFlowControl *fc;
2407 GCC_check_connections ();
2408 log_message (&msg->header, peer, &msg->cid);
2409 c = connection_get (&msg->cid);
2412 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2414 LOG (GNUNET_ERROR_TYPE_DEBUG,
2415 "POLL message on unknown connection %s!\n",
2416 GNUNET_h2s (GC_h2hc (&msg->cid)));
2417 send_broken_unknown (&msg->cid,
2421 GCC_check_connections ();
2425 /* Is this a forward or backward ACK?
2426 * Note: a poll should never be needed in a loopback case,
2427 * since there is no possiblility of packet loss there, so
2428 * this way of discerining FWD/BCK should not be a problem.
2430 if (get_next_hop (c) == peer)
2432 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2435 else if (get_prev_hop (c) == peer)
2437 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2442 GNUNET_break_op (0);
2446 pid = ntohl (msg->pid);
2447 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2448 fc->last_pid_recv = pid;
2449 fwd = fc == &c->bck_fc;
2450 GCC_send_ack (c, fwd, GNUNET_YES);
2451 GCC_check_connections ();
2456 * Check the message against internal state and test if it goes FWD or BCK.
2458 * Updates the PID, state and timeout values for the connection.
2460 * @param message Message to check. It must belong to an existing connection.
2461 * @param cid Connection ID (even if @a c is NULL, the ID is still needed).
2462 * @param c Connection this message should belong. If NULL, check fails.
2463 * @param sender Neighbor that sent the message.
2465 * @return #GNUNET_YES if the message goes FWD.
2466 * #GNUNET_NO if it goes BCK.
2467 * #GNUNET_SYSERR if there is an error (unauthorized sender, ...).
2470 check_message (const struct GNUNET_MessageHeader *message,
2471 const struct GNUNET_CADET_Hash* cid,
2472 struct CadetConnection *c,
2473 struct CadetPeer *sender,
2476 struct CadetFlowControl *fc;
2477 struct CadetPeer *hop;
2481 /* Check connection */
2484 GNUNET_STATISTICS_update (stats,
2485 "# unknown connection",
2487 LOG (GNUNET_ERROR_TYPE_DEBUG,
2488 "%s on unknown connection %s\n",
2489 GC_m2s (ntohs (message->type)),
2490 GNUNET_h2s (GC_h2hc (cid)));
2491 send_broken_unknown (cid,
2495 return GNUNET_SYSERR;
2498 /* Check if origin is as expected */
2499 hop = get_prev_hop (c);
2506 hop = get_next_hop (c);
2507 GNUNET_break (hop == c->next_peer);
2514 /* Unexpected peer sending traffic on a connection. */
2515 GNUNET_break_op (0);
2516 return GNUNET_SYSERR;
2520 /* Check PID for payload messages */
2521 type = ntohs (message->type);
2522 if (GNUNET_MESSAGE_TYPE_CADET_AX == type)
2524 fc = fwd ? &c->bck_fc : &c->fwd_fc;
2525 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u - %u)\n",
2526 pid, fc->last_pid_recv + 1, fc->last_ack_sent);
2527 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
2529 GNUNET_break_op (0);
2530 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
2531 LOG (GNUNET_ERROR_TYPE_WARNING, "Received PID %u, (prev %u), ACK %u\n",
2532 pid, fc->last_pid_recv, fc->last_ack_sent);
2533 return GNUNET_SYSERR;
2535 if (GC_is_pid_bigger (pid, fc->last_pid_recv))
2539 delta = pid - fc->last_pid_recv;
2540 fc->last_pid_recv = pid;
2541 fc->recv_bitmap <<= delta;
2542 fc->recv_bitmap |= 1;
2546 GNUNET_STATISTICS_update (stats, "# out of order PID", 1, GNUNET_NO);
2547 if (GNUNET_NO == is_ooo_ok (fc->last_pid_recv, pid, fc->recv_bitmap))
2549 LOG (GNUNET_ERROR_TYPE_WARNING, "PID %u unexpected (%u+), dropping!\n",
2550 pid, fc->last_pid_recv - 31);
2551 return GNUNET_SYSERR;
2553 fc->recv_bitmap |= get_recv_bitmask (fc->last_pid_recv, pid);
2557 /* Count as connection confirmation. */
2558 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2560 connection_change_state (c, CADET_CONNECTION_READY);
2563 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2564 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2567 connection_reset_timeout (c, fwd);
2574 * Handler for key exchange traffic (Axolotl KX).
2576 * @param peer Message sender (neighbor).
2577 * @param msg Message itself.
2580 GCC_handle_kx (struct CadetPeer *peer,
2581 const struct GNUNET_CADET_KX *msg)
2583 const struct GNUNET_CADET_Hash* cid;
2584 struct CadetConnection *c;
2587 GCC_check_connections ();
2589 log_message (&msg->header, peer, cid);
2591 c = connection_get (cid);
2592 fwd = check_message (&msg->header,
2598 /* If something went wrong, discard message. */
2599 if (GNUNET_SYSERR == fwd)
2601 GNUNET_break_op (0);
2602 GCC_check_connections ();
2606 /* Is this message for us? */
2607 if (GCC_is_terminal (c, fwd))
2609 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2610 GNUNET_STATISTICS_update (stats, "# received KX", 1, GNUNET_NO);
2616 GCT_handle_kx (c->t, &msg[1].header);
2617 GCC_check_connections ();
2621 /* Message not for us: forward to next hop */
2622 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2623 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2624 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2625 GNUNET_NO, NULL, NULL));
2626 GCC_check_connections ();
2631 * Handler for encrypted cadet network traffic (channel mgmt, data).
2633 * @param peer Message sender (neighbor).
2634 * @param msg Message itself.
2637 GCC_handle_encrypted (struct CadetPeer *peer,
2638 const struct GNUNET_CADET_AX *msg)
2640 const struct GNUNET_CADET_Hash* cid;
2641 struct CadetConnection *c;
2645 GCC_check_connections ();
2647 pid = ntohl (msg->pid);
2648 log_message (&msg->header, peer, cid);
2650 c = connection_get (cid);
2651 fwd = check_message (&msg->header,
2657 /* If something went wrong, discard message. */
2658 if (GNUNET_SYSERR == fwd)
2660 GNUNET_break_op (0);
2661 GCC_check_connections ();
2665 /* Is this message for us? */
2666 if (GCC_is_terminal (c, fwd))
2668 GNUNET_STATISTICS_update (stats, "# received encrypted", 1, GNUNET_NO);
2672 GNUNET_break (GNUNET_NO != c->destroy);
2675 GCT_handle_encrypted (c->t, &msg->header);
2676 GCC_send_ack (c, fwd, GNUNET_NO);
2677 GCC_check_connections ();
2681 /* Message not for us: forward to next hop */
2682 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2683 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2684 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2685 GNUNET_NO, NULL, NULL));
2686 GCC_check_connections ();
2691 * Initialize the connections subsystem
2693 * @param c Configuration handle.
2696 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2698 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2700 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2703 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2704 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2705 GNUNET_SCHEDULER_shutdown ();
2710 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2713 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2714 "CADET", "MAX_CONNECTIONS", "MISSING");
2715 GNUNET_SCHEDULER_shutdown ();
2720 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2721 &refresh_connection_time))
2723 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2724 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2725 GNUNET_SCHEDULER_shutdown ();
2728 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2729 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2734 * Destroy each connection on shutdown.
2736 * @param cls Closure (unused).
2737 * @param key Current key code (CID, unused).
2738 * @param value Value in the hash map (`struct CadetConnection`)
2740 * @return #GNUNET_YES, because we should continue to iterate
2743 shutdown_iterator (void *cls,
2744 const struct GNUNET_HashCode *key,
2747 struct CadetConnection *c = value;
2749 c->state = CADET_CONNECTION_DESTROYED;
2756 * Shut down the connections subsystem.
2761 LOG (GNUNET_ERROR_TYPE_DEBUG, "Shutting down connections\n");
2762 GCC_check_connections ();
2763 GNUNET_CONTAINER_multihashmap_iterate (connections,
2766 GNUNET_CONTAINER_multihashmap_destroy (connections);
2772 * Create a connection.
2774 * @param cid Connection ID (either created locally or imposed remotely).
2775 * @param t Tunnel this connection belongs to (or NULL for transit connections);
2776 * @param path Path this connection has to use (copy is made).
2777 * @param own_pos Own position in the @c path path.
2779 * @return Newly created connection.
2780 * NULL in case of error: own id not in path, wrong neighbors, ...
2782 struct CadetConnection *
2783 GCC_new (const struct GNUNET_CADET_Hash *cid,
2784 struct CadetTunnel *t,
2785 struct CadetPeerPath *path,
2786 unsigned int own_pos)
2788 struct CadetConnection *c;
2789 struct CadetPeerPath *cpath;
2791 GCC_check_connections ();
2792 cpath = path_duplicate (path);
2793 GNUNET_assert (NULL != cpath);
2794 c = GNUNET_new (struct CadetConnection);
2796 GNUNET_assert (GNUNET_OK ==
2797 GNUNET_CONTAINER_multihashmap_put (connections,
2799 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2800 fc_init (&c->fwd_fc);
2801 fc_init (&c->bck_fc);
2806 GNUNET_assert (own_pos <= cpath->length - 1);
2807 c->own_pos = own_pos;
2810 if (GNUNET_OK != register_neighbors (c))
2814 /* We were the origin of this request, this means we have invalid
2815 * info about the paths to reach the destination. We must invalidate
2816 * the *original* path to avoid trying it again in the next minute.
2818 if (2 < path->length)
2819 path_invalidate (path);
2823 GCT_debug(t, GNUNET_ERROR_TYPE_WARNING);
2827 path_destroy (c->path);
2832 LOG (GNUNET_ERROR_TYPE_INFO, "New connection %s\n", GCC_2s (c));
2833 GCC_check_connections ();
2839 * Connection is no longer needed: destroy it.
2841 * Cancels all pending traffic (including possible DESTROY messages), all
2842 * maintenance tasks and removes the connection from neighbor peers and tunnel.
2844 * @param c Connection to destroy.
2847 GCC_destroy (struct CadetConnection *c)
2849 GCC_check_connections ();
2856 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
2857 return; /* -> message_sent -> GCC_destroy. Don't loop. */
2860 LOG (GNUNET_ERROR_TYPE_DEBUG,
2861 "destroying connection %s\n",
2863 LOG (GNUNET_ERROR_TYPE_DEBUG,
2864 " fc's f: %p, b: %p\n",
2865 &c->fwd_fc, &c->bck_fc);
2866 LOG (GNUNET_ERROR_TYPE_DEBUG,
2867 " fc tasks f: %u, b: %u\n",
2868 c->fwd_fc.poll_task,
2869 c->bck_fc.poll_task);
2871 /* Cancel all traffic */
2872 if (NULL != c->path)
2874 connection_cancel_queues (c, GNUNET_YES);
2875 connection_cancel_queues (c, GNUNET_NO);
2876 if (NULL != c->maintenance_q)
2878 GCP_send_cancel (c->maintenance_q);
2879 c->maintenance_q = NULL;
2882 unregister_neighbors (c);
2883 path_destroy (c->path);
2886 /* Delete from tunnel */
2888 GCT_remove_connection (c->t, c);
2890 if (NULL != c->check_duplicates_task)
2891 GNUNET_SCHEDULER_cancel (c->check_duplicates_task);
2892 if (NULL != c->fwd_maintenance_task)
2893 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2894 if (NULL != c->bck_maintenance_task)
2895 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2897 if (GNUNET_NO == c->was_removed)
2899 GNUNET_break (GNUNET_YES ==
2900 GNUNET_CONTAINER_multihashmap_remove (connections,
2904 GNUNET_STATISTICS_update (stats,
2909 GCC_check_connections ();
2914 * Get the connection ID.
2916 * @param c Connection to get the ID from.
2918 * @return ID of the connection.
2920 const struct GNUNET_CADET_Hash *
2921 GCC_get_id (const struct CadetConnection *c)
2928 * Get the connection ID.
2930 * @param c Connection to get the ID from.
2932 * @return ID of the connection.
2934 const struct GNUNET_HashCode *
2935 GCC_get_h (const struct CadetConnection *c)
2937 return GC_h2hc (&c->id);
2942 * Get the connection path.
2944 * @param c Connection to get the path from.
2946 * @return path used by the connection.
2948 const struct CadetPeerPath *
2949 GCC_get_path (const struct CadetConnection *c)
2951 if (GNUNET_NO == c->destroy)
2958 * Get the connection state.
2960 * @param c Connection to get the state from.
2962 * @return state of the connection.
2964 enum CadetConnectionState
2965 GCC_get_state (const struct CadetConnection *c)
2971 * Get the connection tunnel.
2973 * @param c Connection to get the tunnel from.
2975 * @return tunnel of the connection.
2977 struct CadetTunnel *
2978 GCC_get_tunnel (const struct CadetConnection *c)
2985 * Get free buffer space in a connection.
2987 * @param c Connection.
2988 * @param fwd Is query about FWD traffic?
2990 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2993 GCC_get_buffer (struct CadetConnection *c, int fwd)
2995 struct CadetFlowControl *fc;
2997 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2999 LOG (GNUNET_ERROR_TYPE_DEBUG, " Get %s buffer on %s: %u - %u\n",
3000 GC_f2s (fwd), GCC_2s (c), fc->queue_max, fc->queue_n);
3001 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
3003 return (fc->queue_max - fc->queue_n);
3008 * Get how many messages have we allowed to send to us from a direction.
3010 * @param c Connection.
3011 * @param fwd Are we asking about traffic from FWD (BCK messages)?
3013 * @return last_ack_sent - last_pid_recv
3016 GCC_get_allowed (struct CadetConnection *c, int fwd)
3018 struct CadetFlowControl *fc;
3020 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3021 if (CADET_CONNECTION_READY != c->state
3022 || GC_is_pid_bigger (fc->last_pid_recv, fc->last_ack_sent))
3026 return (fc->last_ack_sent - fc->last_pid_recv);
3031 * Get messages queued in a connection.
3033 * @param c Connection.
3034 * @param fwd Is query about FWD traffic?
3036 * @return Number of messages queued.
3039 GCC_get_qn (struct CadetConnection *c, int fwd)
3041 struct CadetFlowControl *fc;
3043 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3050 * Get next PID to use.
3052 * @param c Connection.
3053 * @param fwd Is query about FWD traffic?
3055 * @return Next PID to use.
3058 GCC_get_pid (struct CadetConnection *c, int fwd)
3060 struct CadetFlowControl *fc;
3063 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3071 * Allow the connection to advertise a buffer of the given size.
3073 * The connection will send an @c fwd ACK message (so: in direction !fwd)
3074 * allowing up to last_pid_recv + buffer.
3076 * @param c Connection.
3077 * @param buffer How many more messages the connection can accept.
3078 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
3081 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
3083 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
3084 GCC_2s (c), buffer, GC_f2s (fwd));
3085 send_ack (c, buffer, fwd, GNUNET_NO);
3090 * Notify other peers on a connection of a broken link. Mark connections
3091 * to destroy after all traffic has been sent.
3093 * @param c Connection on which there has been a disconnection.
3094 * @param peer Peer that disconnected.
3097 GCC_neighbor_disconnected (struct CadetConnection *c, struct CadetPeer *peer)
3099 struct CadetFlowControl *fc;
3103 GCC_check_connections ();
3104 strncpy (peer_name, GCP_2s (peer), 16);
3105 peer_name[15] = '\0';
3106 LOG (GNUNET_ERROR_TYPE_DEBUG,
3107 "shutting down %s, %s disconnected\n",
3108 GCC_2s (c), peer_name);
3110 invalidate_paths (c, peer);
3112 fwd = is_fwd (c, peer);
3113 if (GNUNET_SYSERR == fwd)
3118 if ( (GNUNET_YES == GCC_is_terminal (c, fwd)) ||
3119 (GNUNET_NO != c->destroy) )
3121 /* Local shutdown, or other peer already down (hence 'c->destroy');
3122 so there is no one to notify about this, just clean up. */
3124 GCC_check_connections ();
3127 /* Mark FlowControl towards the peer as unavaliable. */
3128 fc = fwd ? &c->bck_fc : &c->fwd_fc;
3131 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
3133 /* Connection will have at least one pending message
3134 * (the one we just scheduled), so delay destruction
3135 * and remove from map so we don't use accidentally. */
3137 GNUNET_assert (GNUNET_NO == c->was_removed);
3138 c->was_removed = GNUNET_YES;
3139 GNUNET_break (GNUNET_YES ==
3140 GNUNET_CONTAINER_multihashmap_remove (connections,
3143 /* Cancel queue in the direction that just died. */
3144 connection_cancel_queues (c, ! fwd);
3145 GCC_stop_poll (c, ! fwd);
3146 unregister_neighbors (c);
3147 GCC_check_connections ();
3152 * Is this peer the first one on the connection?
3154 * @param c Connection.
3155 * @param fwd Is this about fwd traffic?
3157 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
3160 GCC_is_origin (struct CadetConnection *c, int fwd)
3162 if (!fwd && c->path->length - 1 == c->own_pos )
3164 if (fwd && 0 == c->own_pos)
3171 * Is this peer the last one on the connection?
3173 * @param c Connection.
3174 * @param fwd Is this about fwd traffic?
3175 * Note that the ROOT is the terminal for BCK traffic!
3177 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
3180 GCC_is_terminal (struct CadetConnection *c, int fwd)
3182 return GCC_is_origin (c, ! fwd);
3187 * See if we are allowed to send by the next hop in the given direction.
3189 * @param c Connection.
3190 * @param fwd Is this about fwd traffic?
3192 * @return #GNUNET_YES in case it's OK to send.
3195 GCC_is_sendable (struct CadetConnection *c, int fwd)
3197 struct CadetFlowControl *fc;
3199 LOG (GNUNET_ERROR_TYPE_DEBUG,
3200 " checking sendability of %s traffic on %s\n",
3201 GC_f2s (fwd), GCC_2s (c));
3207 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3208 LOG (GNUNET_ERROR_TYPE_DEBUG,
3209 " last ack recv: %u, last pid sent: %u\n",
3210 fc->last_ack_recv, fc->last_pid_sent);
3211 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
3213 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
3216 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
3222 * Check if this connection is a direct one (never trim a direct connection).
3224 * @param c Connection.
3226 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
3229 GCC_is_direct (struct CadetConnection *c)
3231 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
3236 * Sends an already built message on a connection, properly registering
3237 * all used resources.
3239 * @param message Message to send. Function makes a copy of it.
3240 * If message is not hop-by-hop, decrements TTL of copy.
3241 * @param payload_type Type of payload, in case the message is encrypted.
3242 * @param payload_id ID of the payload (PID, ACK, ...).
3243 * @param c Connection on which this message is transmitted.
3244 * @param fwd Is this a fwd message?
3245 * @param force Force the connection to accept the message (buffer overfill).
3246 * @param cont Continuation called once message is sent. Can be NULL.
3247 * @param cont_cls Closure for @c cont.
3249 * @return Handle to cancel the message before it's sent.
3250 * NULL on error or if @c cont is NULL.
3251 * Invalid on @c cont call.
3253 struct CadetConnectionQueue *
3254 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
3255 uint16_t payload_type, uint32_t payload_id,
3256 struct CadetConnection *c, int fwd, int force,
3257 GCC_sent cont, void *cont_cls)
3259 struct GNUNET_CADET_AX *axmsg;
3260 struct GNUNET_CADET_KX *kmsg;
3261 struct GNUNET_CADET_ACK *amsg;
3262 struct GNUNET_CADET_Poll *pmsg;
3263 struct GNUNET_CADET_ConnectionDestroy *dmsg;
3264 struct GNUNET_CADET_ConnectionBroken *bmsg;
3265 struct CadetFlowControl *fc;
3266 struct CadetConnectionQueue *q;
3267 struct GNUNET_MessageHeader *copy;
3272 GCC_check_connections ();
3273 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3274 if (0 == fc->queue_max)
3280 size = ntohs (message->size);
3281 copy = GNUNET_malloc (size);
3282 GNUNET_memcpy (copy, message, size);
3283 type = ntohs (message->type);
3284 LOG (GNUNET_ERROR_TYPE_INFO,
3285 "--> %s (%s %4u) on conn %s (%p) %s [%5u]\n",
3286 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), c,
3288 droppable = (GNUNET_NO == force);
3291 case GNUNET_MESSAGE_TYPE_CADET_AX:
3292 axmsg = (struct GNUNET_CADET_AX *) copy;
3294 axmsg->pid = htonl (GCC_get_pid (c, fwd));
3295 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
3296 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
3297 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
3298 if (GNUNET_YES == droppable)
3304 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
3308 case GNUNET_MESSAGE_TYPE_CADET_KX:
3309 kmsg = (struct GNUNET_CADET_KX *) copy;
3310 kmsg->reserved = htonl (0);
3314 case GNUNET_MESSAGE_TYPE_CADET_ACK:
3315 amsg = (struct GNUNET_CADET_ACK *) copy;
3317 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
3318 droppable = GNUNET_NO;
3321 case GNUNET_MESSAGE_TYPE_CADET_POLL:
3322 pmsg = (struct GNUNET_CADET_Poll *) copy;
3324 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL %u\n", ntohl (pmsg->pid));
3325 droppable = GNUNET_NO;
3328 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
3329 dmsg = (struct GNUNET_CADET_ConnectionDestroy *) copy;
3330 dmsg->reserved = htonl (0);
3334 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
3335 bmsg = (struct GNUNET_CADET_ConnectionBroken *) copy;
3336 bmsg->reserved = htonl (0);
3340 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
3341 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
3342 GNUNET_break (0); /* Should've used specific functions. */
3351 if (fc->queue_n > fc->queue_max && droppable)
3353 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
3356 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue full: %u/%u\n",
3357 fc->queue_n, fc->queue_max);
3358 if (GNUNET_MESSAGE_TYPE_CADET_AX == type)
3363 return NULL; /* Drop this message */
3366 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %s %u\n",
3367 GCC_2s (c), c->pending_messages);
3368 c->pending_messages++;
3370 q = GNUNET_new (struct CadetConnectionQueue);
3371 q->forced = !droppable;
3372 q->peer_q = GCP_send (get_hop (c, fwd), copy,
3373 payload_type, payload_id,
3375 &conn_message_sent, q);
3376 if (NULL == q->peer_q)
3378 LOG (GNUNET_ERROR_TYPE_DEBUG, "dropping msg on %s, NULL q\n", GCC_2s (c));
3381 GCC_check_connections ();
3385 q->cont_cls = cont_cls;
3386 GNUNET_CONTAINER_DLL_insert (fc->q_head, fc->q_tail, q);
3387 GCC_check_connections ();
3388 return (NULL == cont) ? NULL : q;
3393 * Cancel a previously sent message while it's in the queue.
3395 * ONLY can be called before the continuation given to the send function
3396 * is called. Once the continuation is called, the message is no longer in the
3399 * @param q Handle to the queue.
3402 GCC_cancel (struct CadetConnectionQueue *q)
3404 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GCC cancel message\n");
3406 /* send_cancel calls message_sent, which calls q->cont and frees q */
3407 GCP_send_cancel (q->peer_q);
3408 GCC_check_connections ();
3413 * Sends a CREATE CONNECTION message for a path to a peer.
3414 * Changes the connection and tunnel states if necessary.
3416 * @param c Connection to create.
3419 GCC_send_create (struct CadetConnection *c)
3421 enum CadetTunnelCState state;
3424 GCC_check_connections ();
3425 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3426 size += c->path->length * sizeof (struct GNUNET_PeerIdentity);
3428 /* Allocate message on the stack */
3429 unsigned char cbuf[size];
3430 struct GNUNET_CADET_ConnectionCreate *msg;
3431 struct GNUNET_PeerIdentity *peers;
3433 msg = (struct GNUNET_CADET_ConnectionCreate *) cbuf;
3434 msg->header.size = htons (size);
3435 msg->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE);
3436 msg->reserved = htonl (0);
3437 msg->cid = *GCC_get_id (c);
3438 peers = (struct GNUNET_PeerIdentity *) &msg[1];
3439 for (int i = 0; i < c->path->length; i++)
3441 GNUNET_PEER_resolve (c->path->peers[i], peers++);
3443 GNUNET_assert (NULL == c->maintenance_q);
3444 c->maintenance_q = GCP_send (get_next_hop (c),
3446 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, 0,
3448 &conn_message_sent, NULL);
3451 LOG (GNUNET_ERROR_TYPE_INFO, "==> %s %19s on conn %s (%p) FWD [%5u]\n",
3452 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE), "",
3453 GCC_2s (c), c, size);
3454 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3455 c, c->pending_messages);
3456 c->pending_messages++;
3458 state = GCT_get_cstate (c->t);
3459 if (CADET_TUNNEL_SEARCHING == state || CADET_TUNNEL_NEW == state)
3460 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
3461 if (CADET_CONNECTION_NEW == c->state)
3462 connection_change_state (c, CADET_CONNECTION_SENT);
3463 GCC_check_connections ();
3468 * Send an ACK on the appropriate connection/channel, depending on
3469 * the direction and the position of the peer.
3471 * @param c Which connection to send the hop-by-hop ACK.
3472 * @param fwd Is this a fwd ACK? (will go dest->root).
3473 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
3476 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
3478 unsigned int buffer;
3480 GCC_check_connections ();
3481 LOG (GNUNET_ERROR_TYPE_DEBUG, "GCC send %s ACK on %s\n",
3482 GC_f2s (fwd), GCC_2s (c));
3490 if (GNUNET_NO != c->destroy)
3492 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
3493 GCC_check_connections ();
3497 /* Get available buffer space */
3498 if (GCC_is_terminal (c, fwd))
3500 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
3501 buffer = GCT_get_channels_buffer (c->t);
3505 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
3506 buffer = GCC_get_buffer (c, fwd);
3508 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
3509 if (0 == buffer && GNUNET_NO == force)
3511 GCC_check_connections ();
3515 /* Send available buffer space */
3516 if (GNUNET_YES == GCC_is_origin (c, fwd))
3518 GNUNET_assert (NULL != c->t);
3519 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
3520 GCT_unchoke_channels (c->t);
3524 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
3525 send_ack (c, buffer, fwd, force);
3527 GCC_check_connections ();
3532 * Send a message to all peers in this connection that the connection
3533 * is no longer valid.
3535 * If some peer should not receive the message, it should be zero'ed out
3536 * before calling this function.
3538 * @param c The connection whose peers to notify.
3541 GCC_send_destroy (struct CadetConnection *c)
3543 struct GNUNET_CADET_ConnectionDestroy msg;
3545 if (GNUNET_YES == c->destroy)
3547 GCC_check_connections ();
3548 msg.header.size = htons (sizeof (msg));
3549 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
3551 LOG (GNUNET_ERROR_TYPE_DEBUG,
3552 " sending connection destroy for connection %s\n",
3555 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3556 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3558 GNUNET_YES, NULL, NULL));
3559 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3560 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3562 GNUNET_YES, NULL, NULL));
3564 GCC_check_connections ();
3569 * @brief Start a polling timer for the connection.
3571 * When a neighbor does not accept more traffic on the connection it could be
3572 * caused by a simple congestion or by a lost ACK. Polling enables to check
3573 * for the lastest ACK status for a connection.
3575 * @param c Connection.
3576 * @param fwd Should we poll in the FWD direction?
3579 GCC_start_poll (struct CadetConnection *c, int fwd)
3581 struct CadetFlowControl *fc;
3583 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3584 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL %s requested\n",
3586 if (NULL != fc->poll_task || NULL != fc->poll_msg)
3588 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL already in progress (t: %p, m: %p)\n",
3589 fc->poll_task, fc->poll_msg);
3592 if (0 == fc->queue_max)
3594 /* Should not be needed, traffic should've been cancelled. */
3596 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL not possible, peer disconnected\n");
3599 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL started on request\n");
3600 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
3607 * @brief Stop polling a connection for ACKs.
3609 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3611 * @param c Connection.
3612 * @param fwd Should we stop the poll in the FWD direction?
3615 GCC_stop_poll (struct CadetConnection *c, int fwd)
3617 struct CadetFlowControl *fc;
3619 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3620 if (NULL != fc->poll_task)
3622 GNUNET_SCHEDULER_cancel (fc->poll_task);
3623 fc->poll_task = NULL;
3625 if (NULL != fc->poll_msg)
3627 GCC_cancel (fc->poll_msg);
3628 fc->poll_msg = NULL;
3634 * Get a (static) string for a connection.
3636 * @param c Connection.
3639 GCC_2s (const struct CadetConnection *c)
3646 static char buf[128];
3648 SPRINTF (buf, "%s (->%s)",
3649 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3652 return GNUNET_h2s (GC_h2hc (&c->id));
3657 * Log all possible info about the connection state.
3659 * @param c Connection to debug.
3660 * @param level Debug level to use.
3663 GCC_debug (const struct CadetConnection *c, enum GNUNET_ErrorType level)
3668 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
3670 __FILE__, __FUNCTION__, __LINE__);
3676 LOG2 (level, "CCC DEBUG NULL CONNECTION\n");
3680 LOG2 (level, "CCC DEBUG CONNECTION %s\n", GCC_2s (c));
3681 s = path_2s (c->path);
3682 LOG2 (level, "CCC path %s, own pos: %u\n", s, c->own_pos);
3684 LOG2 (level, "CCC state: %s, destroy: %u\n",
3685 GCC_state2s (c->state), c->destroy);
3686 LOG2 (level, "CCC pending messages: %u\n", c->pending_messages);
3687 if (NULL != c->perf)
3688 LOG2 (level, "CCC us/byte: %f\n", c->perf->avg);
3690 LOG2 (level, "CCC FWD flow control:\n");
3691 LOG2 (level, "CCC queue: %u/%u\n", c->fwd_fc.queue_n, c->fwd_fc.queue_max);
3692 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3693 c->fwd_fc.last_pid_sent, c->fwd_fc.last_pid_recv);
3694 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3695 c->fwd_fc.last_ack_sent, c->fwd_fc.last_ack_recv);
3696 LOG2 (level, "CCC recv PID bitmap: %X\n", c->fwd_fc.recv_bitmap);
3697 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3698 c->fwd_fc.poll_task, c->fwd_fc.poll_msg, c->fwd_fc.ack_msg);
3700 LOG2 (level, "CCC BCK flow control:\n");
3701 LOG2 (level, "CCC queue: %u/%u\n", c->bck_fc.queue_n, c->bck_fc.queue_max);
3702 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3703 c->bck_fc.last_pid_sent, c->bck_fc.last_pid_recv);
3704 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3705 c->bck_fc.last_ack_sent, c->bck_fc.last_ack_recv);
3706 LOG2 (level, "CCC recv PID bitmap: %X\n", c->bck_fc.recv_bitmap);
3707 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3708 c->bck_fc.poll_task, c->bck_fc.poll_msg, c->bck_fc.ack_msg);
3710 LOG2 (level, "CCC DEBUG CONNECTION END\n");