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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);
1082 msg.reserved = htonl (0);
1085 GNUNET_assert (NULL ==
1086 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, 0, c, fwd,
1087 GNUNET_YES, NULL, NULL));
1088 GCC_check_connections ();
1093 * Send a notification that a connection is broken, when a connection
1094 * isn't even known to the local peer or soon to be destroyed.
1096 * @param connection_id Connection ID.
1097 * @param id1 Peer that has disconnected, probably local peer.
1098 * @param id2 Peer that has disconnected can be NULL if unknown.
1099 * @param neighbor Peer to notify (neighbor who sent the connection).
1102 send_broken_unknown (const struct GNUNET_CADET_Hash *connection_id,
1103 const struct GNUNET_PeerIdentity *id1,
1104 const struct GNUNET_PeerIdentity *id2,
1105 struct CadetPeer *neighbor)
1107 struct GNUNET_CADET_ConnectionBroken msg;
1109 GCC_check_connections ();
1110 LOG (GNUNET_ERROR_TYPE_INFO, "--> BROKEN on unknown connection %s\n",
1111 GNUNET_h2s (GC_h2hc (connection_id)));
1113 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1114 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1115 msg.cid = *connection_id;
1116 msg.reserved = htonl (0);
1121 memset (&msg.peer2, 0, sizeof (msg.peer2));
1122 GNUNET_assert (NULL != GCP_send (neighbor, &msg.header,
1124 NULL, GNUNET_SYSERR, /* connection, fwd */
1125 NULL, NULL)); /* continuation */
1126 GCC_check_connections ();
1131 * Send keepalive packets for a connection.
1133 * @param c Connection to keep alive..
1134 * @param fwd Is this a FWD keepalive? (owner -> dest).
1137 send_connection_keepalive (struct CadetConnection *c, int fwd)
1139 struct GNUNET_MessageHeader msg;
1140 struct CadetFlowControl *fc;
1143 GCC_check_connections ();
1144 LOG (GNUNET_ERROR_TYPE_INFO,
1145 "keepalive %s for connection %s\n",
1146 GC_f2s (fwd), GCC_2s (c));
1148 GNUNET_assert (NULL != c->t);
1149 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1150 tunnel_ready = GNUNET_YES == GCT_has_queued_traffic (c->t)
1151 && CADET_TUNNEL_KEY_OK <= GCT_get_estate (c->t);
1152 if (0 < fc->queue_n || tunnel_ready)
1154 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, traffic in queue\n");
1158 GNUNET_STATISTICS_update (stats, "# keepalives sent", 1, GNUNET_NO);
1160 GNUNET_assert (NULL != c->t);
1161 msg.size = htons (sizeof (msg));
1162 msg.type = htons (GNUNET_MESSAGE_TYPE_CADET_KEEPALIVE);
1164 GNUNET_assert (NULL ==
1165 GCT_send_prebuilt_message (&msg, c->t, c,
1166 GNUNET_NO, NULL, NULL));
1167 GCC_check_connections ();
1172 * Send CONNECTION_{CREATE/ACK} packets for a connection.
1174 * @param c Connection for which to send the message.
1175 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
1178 connection_recreate (struct CadetConnection *c, int fwd)
1180 LOG (GNUNET_ERROR_TYPE_DEBUG,
1181 "sending connection recreate\n");
1183 GCC_send_create (c);
1185 send_connection_ack (c, GNUNET_NO);
1190 * Generic connection timer management.
1191 * Depending on the role of the peer in the connection will send the
1192 * appropriate message (build or keepalive)
1194 * @param c Conncetion to maintain.
1195 * @param fwd Is FWD?
1198 connection_maintain (struct CadetConnection *c, int fwd)
1200 if (GNUNET_NO != c->destroy)
1202 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, being destroyed\n");
1209 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1213 if (CADET_TUNNEL_SEARCHING == GCT_get_cstate (c->t))
1215 /* If status is SEARCHING, why is there a connection? Should be WAITING */
1217 GCT_debug (c->t, GNUNET_ERROR_TYPE_ERROR);
1218 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, tunnel SEARCHING\n");
1219 schedule_next_keepalive (c, fwd);
1224 case CADET_CONNECTION_NEW:
1227 case CADET_CONNECTION_SENT:
1228 connection_recreate (c, fwd);
1230 case CADET_CONNECTION_READY:
1231 send_connection_keepalive (c, fwd);
1240 * Keep the connection alive.
1242 * @param c Connection to keep alive.
1243 * @param fwd Direction.
1246 connection_keepalive (struct CadetConnection *c,
1249 GCC_check_connections ();
1250 LOG (GNUNET_ERROR_TYPE_DEBUG,
1251 "%s keepalive for %s\n",
1252 GC_f2s (fwd), GCC_2s (c));
1255 c->fwd_maintenance_task = NULL;
1257 c->bck_maintenance_task = NULL;
1258 connection_maintain (c, fwd);
1259 GCC_check_connections ();
1260 /* Next execution will be scheduled by message_sent or _maintain*/
1265 * Keep the connection alive in the FWD direction.
1267 * @param cls Closure (connection to keepalive).
1270 connection_fwd_keepalive (void *cls)
1272 struct CadetConnection *c = cls;
1274 GCC_check_connections ();
1275 connection_keepalive (c,
1277 GCC_check_connections ();
1282 * Keep the connection alive in the BCK direction.
1284 * @param cls Closure (connection to keepalive).
1287 connection_bck_keepalive (void *cls)
1289 struct CadetConnection *c = cls;
1291 GCC_check_connections ();
1292 connection_keepalive (c,
1294 GCC_check_connections ();
1299 * Schedule next keepalive task, taking in consideration
1300 * the connection state and number of retries.
1302 * If the peer is not the origin, do nothing.
1304 * @param c Connection for which to schedule the next keepalive.
1305 * @param fwd Direction for the next keepalive.
1308 schedule_next_keepalive (struct CadetConnection *c, int fwd)
1310 struct GNUNET_TIME_Relative delay;
1311 struct GNUNET_SCHEDULER_Task * *task_id;
1312 GNUNET_SCHEDULER_TaskCallback keepalive_task;
1314 GCC_check_connections ();
1315 if (GNUNET_NO == GCC_is_origin (c, fwd))
1318 /* Calculate delay to use, depending on the state of the connection */
1319 if (CADET_CONNECTION_READY == c->state)
1321 delay = refresh_connection_time;
1325 if (1 > c->create_retry)
1326 c->create_retry = 1;
1327 delay = GNUNET_TIME_relative_multiply (create_connection_time,
1329 if (c->create_retry < 64) // TODO make configurable
1330 c->create_retry *= 2;
1333 /* Select direction-dependent parameters */
1334 if (GNUNET_YES == fwd)
1336 task_id = &c->fwd_maintenance_task;
1337 keepalive_task = &connection_fwd_keepalive;
1341 task_id = &c->bck_maintenance_task;
1342 keepalive_task = &connection_bck_keepalive;
1345 /* Check that no one scheduled it before us */
1346 if (NULL != *task_id)
1348 /* No need for a _break. It can happen for instance when sending a SYNACK
1349 * for a duplicate SYN: the first SYNACK scheduled the task. */
1350 GNUNET_SCHEDULER_cancel (*task_id);
1353 /* Schedule the task */
1354 *task_id = GNUNET_SCHEDULER_add_delayed (delay,
1357 LOG (GNUNET_ERROR_TYPE_DEBUG,
1358 "next keepalive in %s\n",
1359 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1360 GCC_check_connections ();
1365 * Cancel all transmissions that belong to a certain connection.
1367 * If the connection is scheduled for destruction and no more messages are left,
1368 * the connection will be destroyed by the continuation call.
1370 * @param c Connection which to cancel. Might be destroyed during this call.
1371 * @param fwd Cancel fwd traffic?
1374 connection_cancel_queues (struct CadetConnection *c,
1377 struct CadetFlowControl *fc;
1379 GCC_check_connections ();
1380 LOG (GNUNET_ERROR_TYPE_DEBUG,
1381 "Cancel %s queues for connection %s\n",
1382 GC_f2s (fwd), GCC_2s (c));
1389 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1390 if (NULL != fc->poll_task)
1392 GNUNET_SCHEDULER_cancel (fc->poll_task);
1393 fc->poll_task = NULL;
1394 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL task for fc %p\n", fc);
1396 if (NULL != fc->poll_msg)
1398 GCC_cancel (fc->poll_msg);
1399 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL msg for fc %p\n", fc);
1402 while (NULL != fc->q_head)
1404 GCC_cancel (fc->q_head);
1406 GCC_check_connections ();
1411 * Function called if a connection has been stalled for a while,
1412 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1414 * @param cls Closure (poll ctx).
1417 send_connection_poll (void *cls);
1421 * Callback called when a queued POLL message is sent.
1423 * @param cls Closure (flow control context).
1424 * @param c Connection this message was on.
1425 * @param q Queue handler this call invalidates.
1426 * @param type Type of message sent.
1427 * @param fwd Was this a FWD going message?
1428 * @param size Size of the message.
1431 poll_sent (void *cls,
1432 struct CadetConnection *c,
1433 struct CadetConnectionQueue *q,
1434 uint16_t type, int fwd, size_t size)
1436 struct CadetFlowControl *fc = cls;
1438 GNUNET_assert (fc->poll_msg == q);
1439 fc->poll_msg = NULL;
1440 if (2 == c->destroy)
1442 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL canceled on shutdown\n");
1445 if (0 == fc->queue_max)
1447 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL cancelled: neighbor disconnected\n");
1450 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL sent for %s, scheduling new one!\n",
1452 GNUNET_assert (NULL == fc->poll_task);
1453 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1454 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1455 &send_connection_poll,
1457 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1462 * Function called if a connection has been stalled for a while,
1463 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1465 * @param cls Closure (poll ctx).
1468 send_connection_poll (void *cls)
1470 struct CadetFlowControl *fc = cls;
1471 struct GNUNET_CADET_Poll msg;
1472 struct CadetConnection *c;
1475 fc->poll_task = NULL;
1476 GCC_check_connections ();
1478 fwd = fc == &c->fwd_fc;
1479 LOG (GNUNET_ERROR_TYPE_DEBUG, "Polling connection %s %s\n",
1480 GCC_2s (c), GC_f2s (fwd));
1482 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_POLL);
1483 msg.header.size = htons (sizeof (msg));
1485 msg.pid = htonl (fc->last_pid_sent);
1486 LOG (GNUNET_ERROR_TYPE_DEBUG, " last pid sent: %u\n", fc->last_pid_sent);
1488 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, fc->last_pid_sent, c,
1489 fc == &c->fwd_fc, GNUNET_YES, &poll_sent, fc);
1490 GNUNET_assert (NULL != fc->poll_msg);
1491 GCC_check_connections ();
1496 * Generic connection timeout implementation.
1498 * Timeout function due to lack of keepalive/traffic from an endpoint.
1499 * Destroys connection if called.
1501 * @param c Connection to destroy.
1502 * @param fwd Was the timeout from the origin? (FWD timeout)
1505 connection_timeout (struct CadetConnection *c, int fwd)
1507 GCC_check_connections ();
1509 LOG (GNUNET_ERROR_TYPE_INFO,
1510 "Connection %s %s timed out. Destroying.\n",
1513 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1515 if (GCC_is_origin (c, fwd)) /* Loopback? Something is wrong! */
1521 /* If dest, send "broken" notification. */
1522 if (GCC_is_terminal (c, fwd))
1524 struct CadetPeer *next_hop;
1526 next_hop = fwd ? get_prev_hop (c) : get_next_hop (c);
1527 send_broken_unknown (&c->id, &my_full_id, NULL, next_hop);
1531 GCC_check_connections ();
1536 * Timeout function due to lack of keepalive/traffic from the owner.
1537 * Destroys connection if called.
1539 * @param cls Closure (connection to destroy).
1542 connection_fwd_timeout (void *cls)
1544 struct CadetConnection *c = cls;
1546 c->fwd_maintenance_task = NULL;
1547 GCC_check_connections ();
1548 connection_timeout (c, GNUNET_YES);
1549 GCC_check_connections ();
1554 * Timeout function due to lack of keepalive/traffic from the destination.
1555 * Destroys connection if called.
1557 * @param cls Closure (connection to destroy).
1560 connection_bck_timeout (void *cls)
1562 struct CadetConnection *c = cls;
1564 c->bck_maintenance_task = NULL;
1565 GCC_check_connections ();
1566 connection_timeout (c, GNUNET_NO);
1567 GCC_check_connections ();
1572 * Resets the connection timeout task, some other message has done the
1574 * - For the first peer on the direction this means to send
1575 * a keepalive or a path confirmation message (either create or ACK).
1576 * - For all other peers, this means to destroy the connection,
1577 * due to lack of activity.
1578 * Starts the timeout if no timeout was running (connection just created).
1580 * @param c Connection whose timeout to reset.
1581 * @param fwd Is this forward?
1583 * TODO use heap to improve efficiency of scheduler.
1586 connection_reset_timeout (struct CadetConnection *c, int fwd)
1588 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1589 if (GCC_is_origin (c, fwd)) /* Startpoint */
1591 schedule_next_keepalive (c, fwd);
1592 if (NULL != c->maintenance_q)
1594 GCP_send_cancel (c->maintenance_q);
1595 c->maintenance_q = NULL; /* Is set to NULL by conn_message_sent anyway */
1598 else /* Relay, endpoint. */
1600 struct GNUNET_TIME_Relative delay;
1601 struct GNUNET_SCHEDULER_Task * *ti;
1602 GNUNET_SCHEDULER_TaskCallback f;
1604 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1607 GNUNET_SCHEDULER_cancel (*ti);
1608 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1609 LOG (GNUNET_ERROR_TYPE_DEBUG,
1610 " timing out in %s\n",
1611 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_NO));
1612 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1613 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1619 * Iterator to compare each connection's path with the path of a new connection.
1621 * If the connection coincides, the c member of path is set to the connection
1622 * and the destroy flag of the connection is set.
1624 * @param cls Closure (new path).
1625 * @param c Connection in the tunnel to check.
1628 check_path (void *cls, struct CadetConnection *c)
1630 struct CadetConnection *new_conn = cls;
1631 struct CadetPeerPath *path = new_conn->path;
1633 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking %s (%p), length %u\n",
1634 GCC_2s (c), c, c->path->length);
1637 && GNUNET_NO == c->destroy
1638 && CADET_CONNECTION_BROKEN != c->state
1639 && CADET_CONNECTION_DESTROYED != c->state
1640 && path_equivalent (path, c->path))
1642 new_conn->destroy = GNUNET_YES; /* Do not mark_destroyed, */
1643 new_conn->path->c = c; /* this is only a flag for the Iterator. */
1644 LOG (GNUNET_ERROR_TYPE_DEBUG, " MATCH!\n");
1650 * Finds out if this path is already being used by an existing connection.
1652 * Checks the tunnel towards the destination to see if it contains
1653 * any connection with the same path.
1655 * If the existing connection is ready, it is kept.
1656 * Otherwise if the sender has a smaller ID that ours, we accept it (and
1657 * the peer will eventually reject our attempt).
1659 * @param path Path to check.
1660 * @return #GNUNET_YES if the tunnel has a connection with the same path,
1661 * #GNUNET_NO otherwise.
1664 does_connection_exist (struct CadetConnection *conn)
1666 struct CadetPeer *p;
1667 struct CadetTunnel *t;
1668 struct CadetConnection *c;
1670 p = GCP_get_short (conn->path->peers[0], GNUNET_NO);
1673 t = GCP_get_tunnel (p);
1677 LOG (GNUNET_ERROR_TYPE_DEBUG, "Checking for duplicates\n");
1679 GCT_iterate_connections (t, &check_path, conn);
1681 if (GNUNET_YES == conn->destroy)
1684 conn->destroy = GNUNET_NO;
1685 conn->path->c = conn;
1686 LOG (GNUNET_ERROR_TYPE_DEBUG, " found duplicate of %s\n", GCC_2s (conn));
1687 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate: %s\n", GCC_2s (c));
1688 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1689 if (CADET_CONNECTION_READY == c->state)
1691 /* The other peer confirmed a live connection with this path,
1692 * why are they trying to duplicate it? */
1693 GNUNET_STATISTICS_update (stats, "# duplicate connections", 1, GNUNET_NO);
1696 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate not ready, connection unique\n");
1701 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s has no duplicates\n", GCC_2s (conn));
1708 * @brief Check if the tunnel this connection belongs to has any other
1709 * connection with the same path, and destroy one if so.
1711 * @param cls Closure (connection to check).
1714 check_duplicates (void *cls)
1716 struct CadetConnection *c = cls;
1718 c->check_duplicates_task = NULL;
1719 if (GNUNET_YES == does_connection_exist (c))
1721 GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1722 send_broken (c, &my_full_id, &my_full_id, GCC_is_origin (c, GNUNET_YES));
1729 * Wait for enough time to let any dead connections time out and check for
1730 * any remaining duplicates.
1732 * @param c Connection that is a potential duplicate.
1735 schedule_check_duplicates (struct CadetConnection *c)
1737 struct GNUNET_TIME_Relative delay;
1739 if (NULL != c->check_duplicates_task)
1741 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 5);
1742 c->check_duplicates_task = GNUNET_SCHEDULER_add_delayed (delay,
1749 * Add the connection to the list of both neighbors.
1751 * @param c Connection.
1753 * @return #GNUNET_OK if everything went fine
1754 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1757 register_neighbors (struct CadetConnection *c)
1759 c->next_peer = get_next_hop (c);
1760 c->prev_peer = get_prev_hop (c);
1761 GNUNET_assert (c->next_peer != c->prev_peer);
1762 LOG (GNUNET_ERROR_TYPE_DEBUG,
1763 "register neighbors for connection %s\n",
1765 path_debug (c->path);
1766 LOG (GNUNET_ERROR_TYPE_DEBUG,
1767 "own pos %u\n", c->own_pos);
1768 LOG (GNUNET_ERROR_TYPE_DEBUG,
1769 "putting connection %s to next peer %p\n",
1772 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n",
1774 GCP_2s (c->next_peer));
1775 LOG (GNUNET_ERROR_TYPE_DEBUG,
1776 "putting connection %s to prev peer %p\n",
1779 LOG (GNUNET_ERROR_TYPE_DEBUG,
1780 "prev peer %p %s\n",
1782 GCP_2s (c->prev_peer));
1784 if ( (GNUNET_NO == GCP_is_neighbor (c->next_peer)) ||
1785 (GNUNET_NO == GCP_is_neighbor (c->prev_peer)) )
1787 if (GCC_is_origin (c, GNUNET_YES))
1788 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1789 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1791 LOG (GNUNET_ERROR_TYPE_DEBUG,
1792 " register neighbors failed\n");
1793 LOG (GNUNET_ERROR_TYPE_DEBUG,
1794 " prev: %s, neighbor?: %d\n",
1795 GCP_2s (c->prev_peer),
1796 GCP_is_neighbor (c->prev_peer));
1797 LOG (GNUNET_ERROR_TYPE_DEBUG,
1798 " next: %s, neighbor?: %d\n",
1799 GCP_2s (c->next_peer),
1800 GCP_is_neighbor (c->next_peer));
1801 return GNUNET_SYSERR;
1803 GCP_add_connection (c->next_peer, c, GNUNET_NO);
1804 GCP_add_connection (c->prev_peer, c, GNUNET_YES);
1811 * Remove the connection from the list of both neighbors.
1813 * @param c Connection.
1816 unregister_neighbors (struct CadetConnection *c)
1818 // struct CadetPeer *peer; FIXME dont use next_peer, prev_peer
1819 /* Either already unregistered or never got registered, it's ok either way. */
1820 if (NULL == c->path)
1822 if (NULL != c->next_peer)
1824 GCP_remove_connection (c->next_peer, c);
1825 c->next_peer = NULL;
1827 if (NULL != c->prev_peer)
1829 GCP_remove_connection (c->prev_peer, c);
1830 c->prev_peer = NULL;
1836 * Invalidates all paths towards all peers that comprise the connection which
1837 * rely on the disconnected peer.
1839 * ~O(n^3) (peers in connection * paths/peer * links/path)
1841 * @param c Connection whose peers' paths to clean.
1842 * @param disconnected Peer that disconnected.
1845 invalidate_paths (struct CadetConnection *c,
1846 struct CadetPeer *disconnected)
1848 struct CadetPeer *peer;
1851 for (i = 0; i < c->path->length; i++)
1853 peer = GCP_get_short (c->path->peers[i], GNUNET_NO);
1855 GCP_notify_broken_link (peer, &my_full_id, GCP_get_id (disconnected));
1861 * Bind the connection to the peer and the tunnel to that peer.
1863 * If the peer has no tunnel, create one. Update tunnel and connection
1864 * data structres to reflect new status.
1866 * @param c Connection.
1870 add_to_peer (struct CadetConnection *c,
1871 struct CadetPeer *peer)
1873 GCP_add_tunnel (peer);
1874 c->t = GCP_get_tunnel (peer);
1875 GCT_add_connection (c->t, c);
1880 * Log receipt of message on stderr (INFO level).
1882 * @param message Message received.
1883 * @param peer Peer who sent the message.
1884 * @param conn_id Connection ID of the message.
1887 log_message (const struct GNUNET_MessageHeader *message,
1888 const struct CadetPeer *peer,
1889 const struct GNUNET_CADET_Hash *conn_id)
1895 size = ntohs (message->size);
1896 type = ntohs (message->type);
1899 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
1900 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
1901 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
1902 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
1908 LOG (GNUNET_ERROR_TYPE_INFO, "<%s %s on conn %s from %s, %6u bytes\n",
1909 arrow, GC_m2s (type), GNUNET_h2s (GC_h2hc (conn_id)),
1910 GCP_2s(peer), (unsigned int) size);
1913 /******************************************************************************/
1914 /******************************** API ***********************************/
1915 /******************************************************************************/
1918 * Handler for connection creation.
1920 * @param peer Message sender (neighbor).
1921 * @param msg Message itself.
1924 GCC_handle_create (struct CadetPeer *peer,
1925 const struct GNUNET_CADET_ConnectionCreate *msg)
1927 const struct GNUNET_CADET_Hash *cid;
1928 struct GNUNET_PeerIdentity *id;
1929 struct CadetPeerPath *path;
1930 struct CadetPeer *dest_peer;
1931 struct CadetPeer *orig_peer;
1932 struct CadetConnection *c;
1933 unsigned int own_pos;
1936 GCC_check_connections ();
1937 size = ntohs (msg->header.size);
1939 /* Calculate hops */
1940 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
1941 if (0 != size % sizeof (struct GNUNET_PeerIdentity))
1943 GNUNET_break_op (0);
1946 size /= sizeof (struct GNUNET_PeerIdentity);
1949 GNUNET_break_op (0);
1952 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1954 /* Get parameters */
1956 log_message (&msg->header, peer, cid);
1957 id = (struct GNUNET_PeerIdentity *) &msg[1];
1958 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
1960 /* Create connection */
1961 c = connection_get (cid);
1964 path = path_build_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
1965 size, myid, &own_pos);
1968 /* Path was malformed, probably our own ID was not in it. */
1969 GNUNET_STATISTICS_update (stats, "# malformed paths", 1, GNUNET_NO);
1970 GNUNET_break_op (0);
1975 /* We received this request from a neighbor, we cannot be origin */
1976 GNUNET_STATISTICS_update (stats, "# fake paths", 1, GNUNET_NO);
1977 GNUNET_break_op (0);
1978 path_destroy (path);
1982 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1983 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1984 c = GCC_new (cid, NULL, path, own_pos);
1987 if (path->length - 1 == own_pos)
1989 /* If we are destination, why did the creation fail? */
1991 path_destroy (path);
1992 GCC_check_connections ();
1995 send_broken_unknown (cid, &my_full_id,
1996 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
1998 path_destroy (path);
1999 GCC_check_connections ();
2002 GCP_add_path_to_all (path, GNUNET_NO);
2003 connection_reset_timeout (c, GNUNET_YES);
2007 path = path_duplicate (c->path);
2009 if (CADET_CONNECTION_NEW == c->state)
2010 connection_change_state (c, CADET_CONNECTION_SENT);
2012 /* Remember peers */
2013 dest_peer = GCP_get (&id[size - 1], GNUNET_YES);
2014 orig_peer = GCP_get (&id[0], GNUNET_YES);
2016 /* Is it a connection to us? */
2017 if (c->own_pos == path->length - 1)
2019 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
2020 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
2022 add_to_peer (c, orig_peer);
2023 if (GNUNET_YES == does_connection_exist (c))
2025 /* Peer created a connection equal to one we think exists
2027 * Solution: Keep both and postpone disambiguation. In the meantime
2028 * the connection will time out or peer will inform us it is broken.
2031 * - Use explicit duplicate.
2032 * - Accept new conn and destroy the old. (interruption in higher level)
2033 * - Keep the one with higher ID / created by peer with higher ID. */
2034 schedule_check_duplicates (c);
2037 if (CADET_TUNNEL_NEW == GCT_get_cstate (c->t))
2038 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
2039 if (NULL == c->maintenance_q)
2040 send_connection_ack (c, GNUNET_NO);
2041 if (CADET_CONNECTION_SENT == c->state)
2042 connection_change_state (c, CADET_CONNECTION_ACK);
2046 /* It's for somebody else! Retransmit. */
2047 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
2048 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
2049 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
2050 GNUNET_assert (NULL ==
2051 GCC_send_prebuilt_message (&msg->header, 0, 0, c,
2052 GNUNET_YES, GNUNET_YES,
2055 path_destroy (path);
2056 GCC_check_connections ();
2061 * Handler for connection confirmations.
2063 * @param peer Message sender (neighbor).
2064 * @param msg Message itself.
2067 GCC_handle_confirm (struct CadetPeer *peer,
2068 const struct GNUNET_CADET_ConnectionACK *msg)
2070 struct CadetConnection *c;
2071 enum CadetConnectionState oldstate;
2074 GCC_check_connections ();
2075 log_message (&msg->header, peer, &msg->cid);
2076 c = connection_get (&msg->cid);
2079 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
2081 LOG (GNUNET_ERROR_TYPE_DEBUG,
2082 " don't know the connection!\n");
2083 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2084 GCC_check_connections ();
2087 if (GNUNET_NO != c->destroy)
2089 GNUNET_assert (CADET_CONNECTION_DESTROYED == c->state);
2090 GNUNET_STATISTICS_update (stats, "# control on dying connection",
2092 LOG (GNUNET_ERROR_TYPE_DEBUG,
2093 "connection %s being destroyed, ignoring confirm\n",
2095 GCC_check_connections ();
2099 oldstate = c->state;
2100 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GCP_2s (peer));
2101 if (get_next_hop (c) == peer)
2103 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
2105 if (CADET_CONNECTION_SENT == oldstate)
2106 connection_change_state (c, CADET_CONNECTION_ACK);
2108 else if (get_prev_hop (c) == peer)
2110 LOG (GNUNET_ERROR_TYPE_DEBUG, " FINAL ACK\n");
2112 connection_change_state (c, CADET_CONNECTION_READY);
2116 GNUNET_STATISTICS_update (stats, "# control on connection from wrong peer",
2118 GNUNET_break_op (0);
2122 connection_reset_timeout (c, fwd);
2124 /* Add path to peers? */
2125 if (NULL != c->path)
2127 GCP_add_path_to_all (c->path, GNUNET_YES);
2134 /* Message for us as creator? */
2135 if (GNUNET_YES == GCC_is_origin (c, GNUNET_YES))
2137 if (GNUNET_NO != fwd)
2142 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
2144 /* If just created, cancel the short timeout and start a long one */
2145 if (CADET_CONNECTION_SENT == oldstate)
2146 connection_reset_timeout (c, GNUNET_YES);
2148 /* Change connection state, send ACK */
2149 connection_change_state (c, CADET_CONNECTION_READY);
2150 send_connection_ack (c, GNUNET_YES);
2152 /* Change tunnel state, trigger KX */
2153 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2154 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2155 GCC_check_connections ();
2159 /* Message for us as destination? */
2160 if (GCC_is_terminal (c, GNUNET_YES))
2162 if (GNUNET_YES != fwd)
2167 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
2169 /* If just created, cancel the short timeout and start a long one */
2170 if (CADET_CONNECTION_ACK == oldstate)
2171 connection_reset_timeout (c, GNUNET_NO);
2173 /* Change tunnel state */
2174 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2175 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2176 GCC_check_connections ();
2180 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2181 GNUNET_assert (NULL ==
2182 GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2183 GNUNET_YES, NULL, NULL));
2184 GCC_check_connections ();
2190 * Handler for notifications of broken connections.
2192 * @param peer Message sender (neighbor).
2193 * @param msg Message itself.
2196 GCC_handle_broken (struct CadetPeer *peer,
2197 const struct GNUNET_CADET_ConnectionBroken *msg)
2199 struct CadetConnection *c;
2200 struct CadetTunnel *t;
2203 GCC_check_connections ();
2204 log_message (&msg->header, peer, &msg->cid);
2205 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n", GNUNET_i2s (&msg->peer1));
2206 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n", GNUNET_i2s (&msg->peer2));
2207 c = connection_get (&msg->cid);
2210 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
2211 GNUNET_STATISTICS_update (stats, "# duplicate CONNECTION_BROKEN",
2213 GCC_check_connections ();
2219 fwd = is_fwd (c, peer);
2220 if (GNUNET_SYSERR == fwd)
2222 GNUNET_break_op (0);
2223 GCC_check_connections ();
2227 if (GCC_is_terminal (c, fwd))
2229 struct CadetPeer *endpoint;
2233 /* A terminal connection should not have 't' set to NULL. */
2235 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
2238 endpoint = GCP_get_short (c->path->peers[c->path->length - 1], GNUNET_YES);
2239 if (2 < c->path->length)
2240 path_invalidate (c->path);
2241 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
2243 connection_change_state (c, CADET_CONNECTION_BROKEN);
2244 GCT_remove_connection (t, c);
2251 GNUNET_assert (NULL ==
2252 GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2253 GNUNET_YES, NULL, NULL));
2254 connection_cancel_queues (c, !fwd);
2256 GCC_check_connections ();
2262 * Handler for notifications of destroyed connections.
2264 * @param peer Message sender (neighbor).
2265 * @param msg Message itself.
2268 GCC_handle_destroy (struct CadetPeer *peer,
2269 const struct GNUNET_CADET_ConnectionDestroy *msg)
2271 struct CadetConnection *c;
2274 GCC_check_connections ();
2275 log_message (&msg->header, peer, &msg->cid);
2276 c = connection_get (&msg->cid);
2279 /* Probably already got the message from another path,
2280 * destroyed the tunnel and retransmitted to children.
2283 GNUNET_STATISTICS_update (stats,
2284 "# control on unknown connection",
2286 LOG (GNUNET_ERROR_TYPE_DEBUG,
2287 " connection unknown destroyed: previously destroyed?\n");
2288 GCC_check_connections ();
2292 fwd = is_fwd (c, peer);
2293 if (GNUNET_SYSERR == fwd)
2295 GNUNET_break_op (0);
2296 GCC_check_connections ();
2300 if (GNUNET_NO == GCC_is_terminal (c, fwd))
2302 GNUNET_assert (NULL ==
2303 GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2304 GNUNET_YES, NULL, NULL));
2306 else if (0 == c->pending_messages)
2308 LOG (GNUNET_ERROR_TYPE_DEBUG, " directly destroying connection!\n");
2310 GCC_check_connections ();
2316 GCT_remove_connection (c->t, c);
2319 GCC_check_connections ();
2325 * Handler for cadet network traffic hop-by-hop acks.
2327 * @param peer Message sender (neighbor).
2328 * @param msg Message itself.
2331 GCC_handle_ack (struct CadetPeer *peer,
2332 const struct GNUNET_CADET_ACK *msg)
2334 struct CadetConnection *c;
2335 struct CadetFlowControl *fc;
2339 GCC_check_connections ();
2340 log_message (&msg->header, peer, &msg->cid);
2341 c = connection_get (&msg->cid);
2344 GNUNET_STATISTICS_update (stats,
2345 "# ack on unknown connection",
2348 send_broken_unknown (&msg->cid,
2352 GCC_check_connections ();
2356 /* Is this a forward or backward ACK? */
2357 if (get_next_hop (c) == peer)
2362 else if (get_prev_hop (c) == peer)
2369 GNUNET_break_op (0);
2373 ack = ntohl (msg->ack);
2374 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s ACK %u (was %u)\n",
2375 GC_f2s (fwd), ack, fc->last_ack_recv);
2376 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2377 fc->last_ack_recv = ack;
2379 /* Cancel polling if the ACK is big enough. */
2380 if (NULL != fc->poll_task &&
2381 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2383 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2384 GNUNET_SCHEDULER_cancel (fc->poll_task);
2385 fc->poll_task = NULL;
2386 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2389 GCC_check_connections ();
2394 * Handler for cadet network traffic hop-by-hop data counter polls.
2396 * @param peer Message sender (neighbor).
2397 * @param msg Message itself.
2400 GCC_handle_poll (struct CadetPeer *peer,
2401 const struct GNUNET_CADET_Poll *msg)
2403 struct CadetConnection *c;
2404 struct CadetFlowControl *fc;
2408 GCC_check_connections ();
2409 log_message (&msg->header, peer, &msg->cid);
2410 c = connection_get (&msg->cid);
2413 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2415 LOG (GNUNET_ERROR_TYPE_DEBUG,
2416 "POLL message on unknown connection %s!\n",
2417 GNUNET_h2s (GC_h2hc (&msg->cid)));
2418 send_broken_unknown (&msg->cid,
2422 GCC_check_connections ();
2426 /* Is this a forward or backward ACK?
2427 * Note: a poll should never be needed in a loopback case,
2428 * since there is no possiblility of packet loss there, so
2429 * this way of discerining FWD/BCK should not be a problem.
2431 if (get_next_hop (c) == peer)
2433 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2436 else if (get_prev_hop (c) == peer)
2438 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2443 GNUNET_break_op (0);
2447 pid = ntohl (msg->pid);
2448 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2449 fc->last_pid_recv = pid;
2450 fwd = fc == &c->bck_fc;
2451 GCC_send_ack (c, fwd, GNUNET_YES);
2452 GCC_check_connections ();
2457 * Check the message against internal state and test if it goes FWD or BCK.
2459 * Updates the PID, state and timeout values for the connection.
2461 * @param message Message to check. It must belong to an existing connection.
2462 * @param cid Connection ID (even if @a c is NULL, the ID is still needed).
2463 * @param c Connection this message should belong. If NULL, check fails.
2464 * @param sender Neighbor that sent the message.
2466 * @return #GNUNET_YES if the message goes FWD.
2467 * #GNUNET_NO if it goes BCK.
2468 * #GNUNET_SYSERR if there is an error (unauthorized sender, ...).
2471 check_message (const struct GNUNET_MessageHeader *message,
2472 const struct GNUNET_CADET_Hash* cid,
2473 struct CadetConnection *c,
2474 struct CadetPeer *sender,
2477 struct CadetFlowControl *fc;
2478 struct CadetPeer *hop;
2482 /* Check connection */
2485 GNUNET_STATISTICS_update (stats,
2486 "# unknown connection",
2488 LOG (GNUNET_ERROR_TYPE_DEBUG,
2489 "%s on unknown connection %s\n",
2490 GC_m2s (ntohs (message->type)),
2491 GNUNET_h2s (GC_h2hc (cid)));
2492 send_broken_unknown (cid,
2496 return GNUNET_SYSERR;
2499 /* Check if origin is as expected */
2500 hop = get_prev_hop (c);
2507 hop = get_next_hop (c);
2508 GNUNET_break (hop == c->next_peer);
2515 /* Unexpected peer sending traffic on a connection. */
2516 GNUNET_break_op (0);
2517 return GNUNET_SYSERR;
2521 /* Check PID for payload messages */
2522 type = ntohs (message->type);
2523 if (GNUNET_MESSAGE_TYPE_CADET_AX == type)
2525 fc = fwd ? &c->bck_fc : &c->fwd_fc;
2526 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u - %u)\n",
2527 pid, fc->last_pid_recv + 1, fc->last_ack_sent);
2528 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
2530 GNUNET_break_op (0);
2531 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
2532 LOG (GNUNET_ERROR_TYPE_WARNING, "Received PID %u, (prev %u), ACK %u\n",
2533 pid, fc->last_pid_recv, fc->last_ack_sent);
2534 return GNUNET_SYSERR;
2536 if (GC_is_pid_bigger (pid, fc->last_pid_recv))
2540 delta = pid - fc->last_pid_recv;
2541 fc->last_pid_recv = pid;
2542 fc->recv_bitmap <<= delta;
2543 fc->recv_bitmap |= 1;
2547 GNUNET_STATISTICS_update (stats, "# out of order PID", 1, GNUNET_NO);
2548 if (GNUNET_NO == is_ooo_ok (fc->last_pid_recv, pid, fc->recv_bitmap))
2550 LOG (GNUNET_ERROR_TYPE_WARNING, "PID %u unexpected (%u+), dropping!\n",
2551 pid, fc->last_pid_recv - 31);
2552 return GNUNET_SYSERR;
2554 fc->recv_bitmap |= get_recv_bitmask (fc->last_pid_recv, pid);
2558 /* Count as connection confirmation. */
2559 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2561 connection_change_state (c, CADET_CONNECTION_READY);
2564 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2565 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2568 connection_reset_timeout (c, fwd);
2575 * Handler for key exchange traffic (Axolotl KX).
2577 * @param peer Message sender (neighbor).
2578 * @param msg Message itself.
2581 GCC_handle_kx (struct CadetPeer *peer,
2582 const struct GNUNET_CADET_KX *msg)
2584 const struct GNUNET_CADET_Hash* cid;
2585 struct CadetConnection *c;
2588 GCC_check_connections ();
2590 log_message (&msg->header, peer, cid);
2592 c = connection_get (cid);
2593 fwd = check_message (&msg->header,
2599 /* If something went wrong, discard message. */
2600 if (GNUNET_SYSERR == fwd)
2602 GNUNET_break_op (0);
2603 GCC_check_connections ();
2607 /* Is this message for us? */
2608 if (GCC_is_terminal (c, fwd))
2610 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2611 GNUNET_STATISTICS_update (stats, "# received KX", 1, GNUNET_NO);
2617 GCT_handle_kx (c->t, &msg[1].header);
2618 GCC_check_connections ();
2622 /* Message not for us: forward to next hop */
2623 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2624 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2625 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2626 GNUNET_NO, NULL, NULL));
2627 GCC_check_connections ();
2632 * Handler for encrypted cadet network traffic (channel mgmt, data).
2634 * @param peer Message sender (neighbor).
2635 * @param msg Message itself.
2638 GCC_handle_encrypted (struct CadetPeer *peer,
2639 const struct GNUNET_CADET_AX *msg)
2641 const struct GNUNET_CADET_Hash* cid;
2642 struct CadetConnection *c;
2646 GCC_check_connections ();
2648 pid = ntohl (msg->pid);
2649 log_message (&msg->header, peer, cid);
2651 c = connection_get (cid);
2652 fwd = check_message (&msg->header,
2658 /* If something went wrong, discard message. */
2659 if (GNUNET_SYSERR == fwd)
2661 GNUNET_break_op (0);
2662 GCC_check_connections ();
2666 /* Is this message for us? */
2667 if (GCC_is_terminal (c, fwd))
2669 GNUNET_STATISTICS_update (stats, "# received encrypted", 1, GNUNET_NO);
2673 GNUNET_break (GNUNET_NO != c->destroy);
2676 GCT_handle_encrypted (c->t, &msg->header);
2677 GCC_send_ack (c, fwd, GNUNET_NO);
2678 GCC_check_connections ();
2682 /* Message not for us: forward to next hop */
2683 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2684 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2685 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2686 GNUNET_NO, NULL, NULL));
2687 GCC_check_connections ();
2692 * Initialize the connections subsystem
2694 * @param c Configuration handle.
2697 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2699 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2701 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2704 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2705 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2706 GNUNET_SCHEDULER_shutdown ();
2711 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2714 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2715 "CADET", "MAX_CONNECTIONS", "MISSING");
2716 GNUNET_SCHEDULER_shutdown ();
2721 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2722 &refresh_connection_time))
2724 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2725 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2726 GNUNET_SCHEDULER_shutdown ();
2729 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2730 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2735 * Destroy each connection on shutdown.
2737 * @param cls Closure (unused).
2738 * @param key Current key code (CID, unused).
2739 * @param value Value in the hash map (`struct CadetConnection`)
2741 * @return #GNUNET_YES, because we should continue to iterate
2744 shutdown_iterator (void *cls,
2745 const struct GNUNET_HashCode *key,
2748 struct CadetConnection *c = value;
2750 c->state = CADET_CONNECTION_DESTROYED;
2757 * Shut down the connections subsystem.
2762 LOG (GNUNET_ERROR_TYPE_DEBUG, "Shutting down connections\n");
2763 GCC_check_connections ();
2764 GNUNET_CONTAINER_multihashmap_iterate (connections,
2767 GNUNET_CONTAINER_multihashmap_destroy (connections);
2773 * Create a connection.
2775 * @param cid Connection ID (either created locally or imposed remotely).
2776 * @param t Tunnel this connection belongs to (or NULL for transit connections);
2777 * @param path Path this connection has to use (copy is made).
2778 * @param own_pos Own position in the @c path path.
2780 * @return Newly created connection.
2781 * NULL in case of error: own id not in path, wrong neighbors, ...
2783 struct CadetConnection *
2784 GCC_new (const struct GNUNET_CADET_Hash *cid,
2785 struct CadetTunnel *t,
2786 struct CadetPeerPath *path,
2787 unsigned int own_pos)
2789 struct CadetConnection *c;
2790 struct CadetPeerPath *cpath;
2792 GCC_check_connections ();
2793 cpath = path_duplicate (path);
2794 GNUNET_assert (NULL != cpath);
2795 c = GNUNET_new (struct CadetConnection);
2797 GNUNET_assert (GNUNET_OK ==
2798 GNUNET_CONTAINER_multihashmap_put (connections,
2800 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2801 fc_init (&c->fwd_fc);
2802 fc_init (&c->bck_fc);
2807 GNUNET_assert (own_pos <= cpath->length - 1);
2808 c->own_pos = own_pos;
2811 if (GNUNET_OK != register_neighbors (c))
2815 /* We were the origin of this request, this means we have invalid
2816 * info about the paths to reach the destination. We must invalidate
2817 * the *original* path to avoid trying it again in the next minute.
2819 if (2 < path->length)
2820 path_invalidate (path);
2824 GCT_debug(t, GNUNET_ERROR_TYPE_WARNING);
2828 path_destroy (c->path);
2833 LOG (GNUNET_ERROR_TYPE_INFO, "New connection %s\n", GCC_2s (c));
2834 GCC_check_connections ();
2840 * Connection is no longer needed: destroy it.
2842 * Cancels all pending traffic (including possible DESTROY messages), all
2843 * maintenance tasks and removes the connection from neighbor peers and tunnel.
2845 * @param c Connection to destroy.
2848 GCC_destroy (struct CadetConnection *c)
2850 GCC_check_connections ();
2857 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
2858 return; /* -> message_sent -> GCC_destroy. Don't loop. */
2861 LOG (GNUNET_ERROR_TYPE_DEBUG,
2862 "destroying connection %s\n",
2864 LOG (GNUNET_ERROR_TYPE_DEBUG,
2865 " fc's f: %p, b: %p\n",
2866 &c->fwd_fc, &c->bck_fc);
2867 LOG (GNUNET_ERROR_TYPE_DEBUG,
2868 " fc tasks f: %u, b: %u\n",
2869 c->fwd_fc.poll_task,
2870 c->bck_fc.poll_task);
2872 /* Cancel all traffic */
2873 if (NULL != c->path)
2875 connection_cancel_queues (c, GNUNET_YES);
2876 connection_cancel_queues (c, GNUNET_NO);
2877 if (NULL != c->maintenance_q)
2879 GCP_send_cancel (c->maintenance_q);
2880 c->maintenance_q = NULL;
2883 unregister_neighbors (c);
2884 path_destroy (c->path);
2887 /* Delete from tunnel */
2889 GCT_remove_connection (c->t, c);
2891 if (NULL != c->check_duplicates_task)
2892 GNUNET_SCHEDULER_cancel (c->check_duplicates_task);
2893 if (NULL != c->fwd_maintenance_task)
2894 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2895 if (NULL != c->bck_maintenance_task)
2896 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2898 if (GNUNET_NO == c->was_removed)
2900 GNUNET_break (GNUNET_YES ==
2901 GNUNET_CONTAINER_multihashmap_remove (connections,
2905 GNUNET_STATISTICS_update (stats,
2910 GCC_check_connections ();
2915 * Get the connection ID.
2917 * @param c Connection to get the ID from.
2919 * @return ID of the connection.
2921 const struct GNUNET_CADET_Hash *
2922 GCC_get_id (const struct CadetConnection *c)
2929 * Get the connection ID.
2931 * @param c Connection to get the ID from.
2933 * @return ID of the connection.
2935 const struct GNUNET_HashCode *
2936 GCC_get_h (const struct CadetConnection *c)
2938 return GC_h2hc (&c->id);
2943 * Get the connection path.
2945 * @param c Connection to get the path from.
2947 * @return path used by the connection.
2949 const struct CadetPeerPath *
2950 GCC_get_path (const struct CadetConnection *c)
2952 if (GNUNET_NO == c->destroy)
2959 * Get the connection state.
2961 * @param c Connection to get the state from.
2963 * @return state of the connection.
2965 enum CadetConnectionState
2966 GCC_get_state (const struct CadetConnection *c)
2972 * Get the connection tunnel.
2974 * @param c Connection to get the tunnel from.
2976 * @return tunnel of the connection.
2978 struct CadetTunnel *
2979 GCC_get_tunnel (const struct CadetConnection *c)
2986 * Get free buffer space in a connection.
2988 * @param c Connection.
2989 * @param fwd Is query about FWD traffic?
2991 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2994 GCC_get_buffer (struct CadetConnection *c, int fwd)
2996 struct CadetFlowControl *fc;
2998 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3000 LOG (GNUNET_ERROR_TYPE_DEBUG, " Get %s buffer on %s: %u - %u\n",
3001 GC_f2s (fwd), GCC_2s (c), fc->queue_max, fc->queue_n);
3002 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
3004 return (fc->queue_max - fc->queue_n);
3009 * Get how many messages have we allowed to send to us from a direction.
3011 * @param c Connection.
3012 * @param fwd Are we asking about traffic from FWD (BCK messages)?
3014 * @return last_ack_sent - last_pid_recv
3017 GCC_get_allowed (struct CadetConnection *c, int fwd)
3019 struct CadetFlowControl *fc;
3021 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3022 if (CADET_CONNECTION_READY != c->state
3023 || GC_is_pid_bigger (fc->last_pid_recv, fc->last_ack_sent))
3027 return (fc->last_ack_sent - fc->last_pid_recv);
3032 * Get messages queued in a connection.
3034 * @param c Connection.
3035 * @param fwd Is query about FWD traffic?
3037 * @return Number of messages queued.
3040 GCC_get_qn (struct CadetConnection *c, int fwd)
3042 struct CadetFlowControl *fc;
3044 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3051 * Get next PID to use.
3053 * @param c Connection.
3054 * @param fwd Is query about FWD traffic?
3056 * @return Next PID to use.
3059 GCC_get_pid (struct CadetConnection *c, int fwd)
3061 struct CadetFlowControl *fc;
3064 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3072 * Allow the connection to advertise a buffer of the given size.
3074 * The connection will send an @c fwd ACK message (so: in direction !fwd)
3075 * allowing up to last_pid_recv + buffer.
3077 * @param c Connection.
3078 * @param buffer How many more messages the connection can accept.
3079 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
3082 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
3084 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
3085 GCC_2s (c), buffer, GC_f2s (fwd));
3086 send_ack (c, buffer, fwd, GNUNET_NO);
3091 * Notify other peers on a connection of a broken link. Mark connections
3092 * to destroy after all traffic has been sent.
3094 * @param c Connection on which there has been a disconnection.
3095 * @param peer Peer that disconnected.
3098 GCC_neighbor_disconnected (struct CadetConnection *c, struct CadetPeer *peer)
3100 struct CadetFlowControl *fc;
3104 GCC_check_connections ();
3105 strncpy (peer_name, GCP_2s (peer), 16);
3106 peer_name[15] = '\0';
3107 LOG (GNUNET_ERROR_TYPE_DEBUG,
3108 "shutting down %s, %s disconnected\n",
3109 GCC_2s (c), peer_name);
3111 invalidate_paths (c, peer);
3113 fwd = is_fwd (c, peer);
3114 if (GNUNET_SYSERR == fwd)
3119 if ( (GNUNET_YES == GCC_is_terminal (c, fwd)) ||
3120 (GNUNET_NO != c->destroy) )
3122 /* Local shutdown, or other peer already down (hence 'c->destroy');
3123 so there is no one to notify about this, just clean up. */
3125 GCC_check_connections ();
3128 /* Mark FlowControl towards the peer as unavaliable. */
3129 fc = fwd ? &c->bck_fc : &c->fwd_fc;
3132 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
3134 /* Connection will have at least one pending message
3135 * (the one we just scheduled), so delay destruction
3136 * and remove from map so we don't use accidentally. */
3138 GNUNET_assert (GNUNET_NO == c->was_removed);
3139 c->was_removed = GNUNET_YES;
3140 GNUNET_break (GNUNET_YES ==
3141 GNUNET_CONTAINER_multihashmap_remove (connections,
3144 /* Cancel queue in the direction that just died. */
3145 connection_cancel_queues (c, ! fwd);
3146 GCC_stop_poll (c, ! fwd);
3147 unregister_neighbors (c);
3148 GCC_check_connections ();
3153 * Is this peer the first one on the connection?
3155 * @param c Connection.
3156 * @param fwd Is this about fwd traffic?
3158 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
3161 GCC_is_origin (struct CadetConnection *c, int fwd)
3163 if (!fwd && c->path->length - 1 == c->own_pos )
3165 if (fwd && 0 == c->own_pos)
3172 * Is this peer the last one on the connection?
3174 * @param c Connection.
3175 * @param fwd Is this about fwd traffic?
3176 * Note that the ROOT is the terminal for BCK traffic!
3178 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
3181 GCC_is_terminal (struct CadetConnection *c, int fwd)
3183 return GCC_is_origin (c, ! fwd);
3188 * See if we are allowed to send by the next hop in the given direction.
3190 * @param c Connection.
3191 * @param fwd Is this about fwd traffic?
3193 * @return #GNUNET_YES in case it's OK to send.
3196 GCC_is_sendable (struct CadetConnection *c, int fwd)
3198 struct CadetFlowControl *fc;
3200 LOG (GNUNET_ERROR_TYPE_DEBUG,
3201 " checking sendability of %s traffic on %s\n",
3202 GC_f2s (fwd), GCC_2s (c));
3208 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3209 LOG (GNUNET_ERROR_TYPE_DEBUG,
3210 " last ack recv: %u, last pid sent: %u\n",
3211 fc->last_ack_recv, fc->last_pid_sent);
3212 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
3214 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
3217 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
3223 * Check if this connection is a direct one (never trim a direct connection).
3225 * @param c Connection.
3227 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
3230 GCC_is_direct (struct CadetConnection *c)
3232 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
3237 * Internal implementation of the send function.
3239 * Sends an completely built message on a connection, properly registering
3240 * all used resources.
3242 * @param message Message to send.
3243 * @param payload_type Type of payload, in case the message is encrypted.
3244 * @param payload_id ID of the payload (PID, ACK, ...).
3245 * @param c Connection on which this message is transmitted.
3246 * @param fwd Is this a fwd message?
3247 * @param force Force the connection to accept the message (buffer overfill).
3248 * @param cont Continuation called once message is sent. Can be NULL.
3249 * @param cont_cls Closure for @c cont.
3251 * @return Handle to cancel the message before it's sent.
3252 * NULL on error or if @c cont is NULL.
3253 * Invalid on @c cont call.
3255 static struct CadetConnectionQueue *
3256 send_prebuilt_message (const struct GNUNET_MessageHeader *message,
3257 uint16_t payload_type, uint32_t payload_id,
3258 struct CadetConnection *c, int fwd, int force,
3259 GCC_sent cont, void *cont_cls)
3261 struct CadetFlowControl *fc;
3262 struct CadetConnectionQueue *q;
3266 GCC_check_connections ();
3267 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3268 if (0 == fc->queue_max)
3274 size = ntohs (message->size);
3275 type = ntohs (message->type);
3276 LOG (GNUNET_ERROR_TYPE_INFO,
3277 "--> %s (%s %4u) on conn %s (%p) %s [%5u]\n",
3278 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), c,
3282 case GNUNET_MESSAGE_TYPE_CADET_AX:
3283 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
3284 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
3285 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
3286 if (GNUNET_NO == force)
3292 case GNUNET_MESSAGE_TYPE_CADET_KX:
3295 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
3296 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
3297 GNUNET_break (0); /* Should've used specific functions. */
3300 case GNUNET_MESSAGE_TYPE_CADET_ACK:
3301 case GNUNET_MESSAGE_TYPE_CADET_POLL:
3302 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
3303 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
3304 GNUNET_assert (GNUNET_YES == force);
3312 if (fc->queue_n > fc->queue_max && GNUNET_NO == force)
3314 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
3317 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue full: %u/%u\n",
3318 fc->queue_n, fc->queue_max);
3319 if (GNUNET_MESSAGE_TYPE_CADET_AX == type)
3323 return NULL; /* Drop this message */
3326 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %s %u\n",
3327 GCC_2s (c), c->pending_messages);
3328 c->pending_messages++;
3330 q = GNUNET_new (struct CadetConnectionQueue);
3332 q->peer_q = GCP_send (get_hop (c, fwd), message,
3333 payload_type, payload_id,
3335 &conn_message_sent, q);
3336 if (NULL == q->peer_q)
3338 LOG (GNUNET_ERROR_TYPE_DEBUG, "dropping msg on %s, NULL q\n", GCC_2s (c));
3340 GCC_check_connections ();
3344 q->cont_cls = cont_cls;
3345 GNUNET_CONTAINER_DLL_insert (fc->q_head, fc->q_tail, q);
3346 GCC_check_connections ();
3347 return (NULL == cont) ? NULL : q;
3352 * Sends an already built message on a connection, properly registering
3353 * all used resources.
3355 * @param message Message to send.
3356 * @param payload_type Type of payload, in case the message is encrypted.
3357 * @param payload_id ID of the payload (PID, ACK, ...).
3358 * @param c Connection on which this message is transmitted.
3359 * @param fwd Is this a fwd message?
3360 * @param force Force the connection to accept the message (buffer overfill).
3361 * @param cont Continuation called once message is sent. Can be NULL.
3362 * @param cont_cls Closure for @c cont.
3364 * @return Handle to cancel the message before it's sent.
3365 * NULL on error or if @c cont is NULL.
3366 * Invalid on @c cont call.
3368 struct CadetConnectionQueue *
3369 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
3370 uint16_t payload_type, uint32_t payload_id,
3371 struct CadetConnection *c, int fwd, int force,
3372 GCC_sent cont, void *cont_cls)
3377 size = ntohs (message->size);
3378 type = ntohs (message->type);
3380 /* Allocate a copy of the message on the stack, so we can modify it as needed,
3381 * adding the Connection ID, PID, and other data the Tunnel layer doesn't
3384 if (GNUNET_MESSAGE_TYPE_CADET_AX == type
3385 || GNUNET_MESSAGE_TYPE_CADET_KX == type)
3387 struct GNUNET_MessageHeader *copy;
3388 unsigned char cbuf[size];
3390 copy = (struct GNUNET_MessageHeader *) cbuf;
3391 GNUNET_memcpy (copy, message, size);
3392 if (GNUNET_MESSAGE_TYPE_CADET_AX == type)
3394 struct GNUNET_CADET_AX *axmsg;
3396 axmsg = (struct GNUNET_CADET_AX *) copy;
3398 axmsg->pid = htonl (GCC_get_pid (c, fwd));
3400 else /* case GNUNET_MESSAGE_TYPE_CADET_KX */
3402 struct GNUNET_CADET_KX *kmsg;
3404 GNUNET_assert (GNUNET_MESSAGE_TYPE_CADET_KX == type);
3405 kmsg = (struct GNUNET_CADET_KX *) copy;
3406 kmsg->reserved = htonl (0);
3409 return send_prebuilt_message (copy, payload_type, payload_id,
3413 return send_prebuilt_message (message, payload_type, payload_id,
3421 * Cancel a previously sent message while it's in the queue.
3423 * ONLY can be called before the continuation given to the send function
3424 * is called. Once the continuation is called, the message is no longer in the
3427 * @param q Handle to the queue.
3430 GCC_cancel (struct CadetConnectionQueue *q)
3432 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GCC cancel message\n");
3434 /* send_cancel calls message_sent, which calls q->cont and frees q */
3435 GCP_send_cancel (q->peer_q);
3436 GCC_check_connections ();
3441 * Sends a CREATE CONNECTION message for a path to a peer.
3442 * Changes the connection and tunnel states if necessary.
3444 * @param c Connection to create.
3447 GCC_send_create (struct CadetConnection *c)
3449 enum CadetTunnelCState state;
3452 GCC_check_connections ();
3453 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3454 size += c->path->length * sizeof (struct GNUNET_PeerIdentity);
3456 /* Allocate message on the stack */
3457 unsigned char cbuf[size];
3458 struct GNUNET_CADET_ConnectionCreate *msg;
3459 struct GNUNET_PeerIdentity *peers;
3461 msg = (struct GNUNET_CADET_ConnectionCreate *) cbuf;
3462 msg->header.size = htons (size);
3463 msg->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE);
3464 msg->reserved = htonl (0);
3465 msg->cid = *GCC_get_id (c);
3466 peers = (struct GNUNET_PeerIdentity *) &msg[1];
3467 for (int i = 0; i < c->path->length; i++)
3469 GNUNET_PEER_resolve (c->path->peers[i], peers++);
3471 GNUNET_assert (NULL == c->maintenance_q);
3472 c->maintenance_q = GCP_send (get_next_hop (c),
3474 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, 0,
3476 &conn_message_sent, NULL);
3479 LOG (GNUNET_ERROR_TYPE_INFO, "==> %s %19s on conn %s (%p) FWD [%5u]\n",
3480 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE), "",
3481 GCC_2s (c), c, size);
3482 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3483 c, c->pending_messages);
3484 c->pending_messages++;
3486 state = GCT_get_cstate (c->t);
3487 if (CADET_TUNNEL_SEARCHING == state || CADET_TUNNEL_NEW == state)
3488 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
3489 if (CADET_CONNECTION_NEW == c->state)
3490 connection_change_state (c, CADET_CONNECTION_SENT);
3491 GCC_check_connections ();
3496 * Send an ACK on the appropriate connection/channel, depending on
3497 * the direction and the position of the peer.
3499 * @param c Which connection to send the hop-by-hop ACK.
3500 * @param fwd Is this a fwd ACK? (will go dest->root).
3501 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
3504 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
3506 unsigned int buffer;
3508 GCC_check_connections ();
3509 LOG (GNUNET_ERROR_TYPE_DEBUG, "GCC send %s ACK on %s\n",
3510 GC_f2s (fwd), GCC_2s (c));
3518 if (GNUNET_NO != c->destroy)
3520 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
3521 GCC_check_connections ();
3525 /* Get available buffer space */
3526 if (GCC_is_terminal (c, fwd))
3528 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
3529 buffer = GCT_get_channels_buffer (c->t);
3533 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
3534 buffer = GCC_get_buffer (c, fwd);
3536 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
3537 if (0 == buffer && GNUNET_NO == force)
3539 GCC_check_connections ();
3543 /* Send available buffer space */
3544 if (GNUNET_YES == GCC_is_origin (c, fwd))
3546 GNUNET_assert (NULL != c->t);
3547 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
3548 GCT_unchoke_channels (c->t);
3552 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
3553 send_ack (c, buffer, fwd, force);
3555 GCC_check_connections ();
3560 * Send a message to all peers in this connection that the connection
3561 * is no longer valid.
3563 * If some peer should not receive the message, it should be zero'ed out
3564 * before calling this function.
3566 * @param c The connection whose peers to notify.
3569 GCC_send_destroy (struct CadetConnection *c)
3571 struct GNUNET_CADET_ConnectionDestroy msg;
3573 if (GNUNET_YES == c->destroy)
3575 GCC_check_connections ();
3576 msg.header.size = htons (sizeof (msg));
3577 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
3579 msg.reserved = htonl (0);
3580 LOG (GNUNET_ERROR_TYPE_DEBUG,
3581 " sending connection destroy for connection %s\n",
3584 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3585 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3587 GNUNET_YES, NULL, NULL));
3588 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3589 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3591 GNUNET_YES, NULL, NULL));
3593 GCC_check_connections ();
3598 * @brief Start a polling timer for the connection.
3600 * When a neighbor does not accept more traffic on the connection it could be
3601 * caused by a simple congestion or by a lost ACK. Polling enables to check
3602 * for the lastest ACK status for a connection.
3604 * @param c Connection.
3605 * @param fwd Should we poll in the FWD direction?
3608 GCC_start_poll (struct CadetConnection *c, int fwd)
3610 struct CadetFlowControl *fc;
3612 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3613 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL %s requested\n",
3615 if (NULL != fc->poll_task || NULL != fc->poll_msg)
3617 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL already in progress (t: %p, m: %p)\n",
3618 fc->poll_task, fc->poll_msg);
3621 if (0 == fc->queue_max)
3623 /* Should not be needed, traffic should've been cancelled. */
3625 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL not possible, peer disconnected\n");
3628 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL started on request\n");
3629 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
3630 &send_connection_poll,
3636 * @brief Stop polling a connection for ACKs.
3638 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3640 * @param c Connection.
3641 * @param fwd Should we stop the poll in the FWD direction?
3644 GCC_stop_poll (struct CadetConnection *c, int fwd)
3646 struct CadetFlowControl *fc;
3648 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3649 if (NULL != fc->poll_task)
3651 GNUNET_SCHEDULER_cancel (fc->poll_task);
3652 fc->poll_task = NULL;
3654 if (NULL != fc->poll_msg)
3656 GCC_cancel (fc->poll_msg);
3657 fc->poll_msg = NULL;
3663 * Get a (static) string for a connection.
3665 * @param c Connection.
3668 GCC_2s (const struct CadetConnection *c)
3675 static char buf[128];
3677 SPRINTF (buf, "%s (->%s)",
3678 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3681 return GNUNET_h2s (GC_h2hc (&c->id));
3686 * Log all possible info about the connection state.
3688 * @param c Connection to debug.
3689 * @param level Debug level to use.
3692 GCC_debug (const struct CadetConnection *c, enum GNUNET_ErrorType level)
3697 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
3699 __FILE__, __FUNCTION__, __LINE__);
3705 LOG2 (level, "CCC DEBUG NULL CONNECTION\n");
3709 LOG2 (level, "CCC DEBUG CONNECTION %s\n", GCC_2s (c));
3710 s = path_2s (c->path);
3711 LOG2 (level, "CCC path %s, own pos: %u\n", s, c->own_pos);
3713 LOG2 (level, "CCC state: %s, destroy: %u\n",
3714 GCC_state2s (c->state), c->destroy);
3715 LOG2 (level, "CCC pending messages: %u\n", c->pending_messages);
3716 if (NULL != c->perf)
3717 LOG2 (level, "CCC us/byte: %f\n", c->perf->avg);
3719 LOG2 (level, "CCC FWD flow control:\n");
3720 LOG2 (level, "CCC queue: %u/%u\n", c->fwd_fc.queue_n, c->fwd_fc.queue_max);
3721 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3722 c->fwd_fc.last_pid_sent, c->fwd_fc.last_pid_recv);
3723 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3724 c->fwd_fc.last_ack_sent, c->fwd_fc.last_ack_recv);
3725 LOG2 (level, "CCC recv PID bitmap: %X\n", c->fwd_fc.recv_bitmap);
3726 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3727 c->fwd_fc.poll_task, c->fwd_fc.poll_msg, c->fwd_fc.ack_msg);
3729 LOG2 (level, "CCC BCK flow control:\n");
3730 LOG2 (level, "CCC queue: %u/%u\n", c->bck_fc.queue_n, c->bck_fc.queue_max);
3731 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3732 c->bck_fc.last_pid_sent, c->bck_fc.last_pid_recv);
3733 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3734 c->bck_fc.last_ack_sent, c->bck_fc.last_ack_recv);
3735 LOG2 (level, "CCC recv PID bitmap: %X\n", c->bck_fc.recv_bitmap);
3736 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3737 c->bck_fc.poll_task, c->bck_fc.poll_msg, c->bck_fc.ack_msg);
3739 LOG2 (level, "CCC DEBUG CONNECTION END\n");