2 This file is part of GNUnet.
3 Copyright (C) 2001-2015 GNUnet e.V.
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18 Boston, MA 02110-1301, USA.
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 GCC_check_connections ();
564 GNUNET_assert (GNUNET_NO == GCC_is_origin (c, fwd));
566 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
567 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
569 LOG (GNUNET_ERROR_TYPE_DEBUG, "send %s ack on %s\n",
570 GC_f2s (fwd), GCC_2s (c));
572 /* Check if we need to transmit the ACK. */
573 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
574 if (3 < delta && buffer < delta && GNUNET_NO == force)
576 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, delta > 3\n");
577 LOG (GNUNET_ERROR_TYPE_DEBUG,
578 " last pid recv: %u, last ack sent: %u\n",
579 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
580 GCC_check_connections ();
584 /* Ok, ACK might be necessary, what PID to ACK? */
585 ack = prev_fc->last_pid_recv + buffer;
586 LOG (GNUNET_ERROR_TYPE_DEBUG,
587 " ACK %u, last PID %u, last ACK %u, qmax %u, q %u\n",
588 ack, prev_fc->last_pid_recv, prev_fc->last_ack_sent,
589 next_fc->queue_max, next_fc->queue_n);
590 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
592 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
593 GCC_check_connections ();
597 /* Check if message is already in queue */
598 if (NULL != prev_fc->ack_msg)
600 if (GC_is_pid_bigger (ack, prev_fc->last_ack_sent))
602 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
603 GCC_cancel (prev_fc->ack_msg);
604 /* GCC_cancel triggers ack_sent(), which clears fc->ack_msg */
608 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
609 GCC_check_connections ();
614 prev_fc->last_ack_sent = ack;
616 /* Build ACK message and send on conn */
617 msg.header.size = htons (sizeof (msg));
618 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_ACK);
619 msg.ack = htonl (ack);
622 prev_fc->ack_msg = GCC_send_prebuilt_message (&msg.header, UINT16_MAX, ack,
625 GNUNET_assert (NULL != prev_fc->ack_msg);
626 GCC_check_connections ();
631 * Update performance information if we are a connection's endpoint.
633 * @param c Connection to update.
634 * @param wait How much time did we wait to send the last message.
635 * @param size Size of the last message.
638 update_perf (struct CadetConnection *c,
639 struct GNUNET_TIME_Relative wait,
642 struct CadetConnectionPerformance *p;
646 return; /* Only endpoints are interested in timing. */
649 usecsperbyte = ((double) wait.rel_value_us) / size;
650 if (p->size == AVG_MSGS)
652 /* Array is full. Substract oldest value, add new one and store. */
653 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
654 p->usecsperbyte[p->idx] = usecsperbyte;
655 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
659 /* Array not yet full. Add current value to avg and store. */
660 p->usecsperbyte[p->idx] = usecsperbyte;
662 p->avg += p->usecsperbyte[p->idx];
666 p->idx = (p->idx + 1) % AVG_MSGS;
671 * Callback called when a connection queued message is sent.
673 * Calculates the average time and connection packet tracking.
675 * @param cls Closure (ConnectionQueue Handle), can be NULL.
676 * @param c Connection this message was on.
677 * @param fwd Was this a FWD going message?
678 * @param sent Was it really sent? (Could have been canceled)
679 * @param type Type of message sent.
680 * @param payload_type Type of payload, if applicable.
681 * @param pid Message ID, or 0 if not applicable (create, destroy, etc).
682 * @param size Size of the message.
683 * @param wait Time spent waiting for core (only the time for THIS message)
686 conn_message_sent (void *cls,
687 struct CadetConnection *c, int fwd, int sent,
688 uint16_t type, uint16_t payload_type, uint32_t pid,
690 struct GNUNET_TIME_Relative wait)
692 struct CadetConnectionQueue *q = cls;
693 struct CadetFlowControl *fc;
696 GCC_check_connections ();
697 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection message_sent\n");
699 /* If c is NULL, nothing to update. */
702 if (type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN
703 && type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY)
705 LOG (GNUNET_ERROR_TYPE_ERROR, "Message %s sent on NULL connection!\n",
708 GCC_check_connections ();
712 LOG (GNUNET_ERROR_TYPE_DEBUG, " %ssent %s %s pid %u\n",
713 sent ? "" : "not ", GC_f2s (fwd),
714 GC_m2s (type), GC_m2s (payload_type), pid);
715 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
717 /* Update flow control info. */
718 fc = fwd ? &c->fwd_fc : &c->bck_fc;
722 GNUNET_CONTAINER_DLL_remove (fc->q_head, fc->q_tail, q);
726 LOG (GNUNET_ERROR_TYPE_DEBUG, " calling cont\n");
727 q->cont (q->cont_cls, c, q, type, fwd, size);
731 else if (type == GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED)
733 /* SHOULD NO LONGER HAPPEN FIXME: REMOVE CASE */
734 // If NULL == q and ENCRYPTED == type, message must have been ch_mngmnt
736 GNUNET_assert (0); // FIXME
738 else /* CONN_CREATE or CONN_ACK */
743 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P- %p %u\n", c, c->pending_messages);
744 c->pending_messages--;
745 if ( (GNUNET_YES == c->destroy) &&
746 (0 == c->pending_messages) )
748 LOG (GNUNET_ERROR_TYPE_DEBUG,
749 "! destroying connection!\n");
751 GCC_check_connections ();
755 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
758 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
759 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
760 c->maintenance_q = NULL;
761 /* Don't trigger a keepalive for sent ACKs, only SYN and SYNACKs */
762 if (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE == type || !fwd)
763 schedule_next_keepalive (c, fwd);
766 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
767 if (GNUNET_YES == sent)
769 GNUNET_assert (NULL != q);
770 fc->last_pid_sent = pid;
771 if (GC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
772 GCC_start_poll (c, fwd);
773 GCC_send_ack (c, fwd, GNUNET_NO);
774 connection_reset_timeout (c, fwd);
777 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
778 if (GNUNET_NO == forced)
781 LOG (GNUNET_ERROR_TYPE_DEBUG,
782 "! accounting pid %u\n",
787 LOG (GNUNET_ERROR_TYPE_DEBUG,
788 "! forced, Q_N not accounting pid %u\n",
793 case GNUNET_MESSAGE_TYPE_CADET_KX:
794 if (GNUNET_YES == sent)
795 connection_reset_timeout (c, fwd);
798 case GNUNET_MESSAGE_TYPE_CADET_POLL:
802 case GNUNET_MESSAGE_TYPE_CADET_ACK:
806 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
807 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
811 LOG (GNUNET_ERROR_TYPE_ERROR, "%s unknown\n", GC_m2s (type));
815 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
817 update_perf (c, wait, size);
818 GCC_check_connections ();
823 * Get the previous hop in a connection
825 * @param c Connection.
827 * @return Previous peer in the connection.
829 static struct CadetPeer *
830 get_prev_hop (const struct CadetConnection *c)
836 LOG (GNUNET_ERROR_TYPE_DEBUG,
837 " get prev hop %s [%u/%u]\n",
838 GCC_2s (c), c->own_pos, c->path->length);
839 if (0 == c->own_pos || c->path->length < 2)
840 id = c->path->peers[0];
842 id = c->path->peers[c->own_pos - 1];
844 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
845 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
847 return GCP_get_short (id, GNUNET_YES);
852 * Get the next hop in a connection
854 * @param c Connection.
856 * @return Next peer in the connection.
858 static struct CadetPeer *
859 get_next_hop (const struct CadetConnection *c)
866 LOG (GNUNET_ERROR_TYPE_DEBUG, " get next hop %s [%u/%u]\n",
867 GCC_2s (c), c->own_pos, c->path->length);
868 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
869 id = c->path->peers[c->path->length - 1];
871 id = c->path->peers[c->own_pos + 1];
873 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
874 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
876 return GCP_get_short (id, GNUNET_YES);
881 * Check that the direct neighbours (previous and next hop)
882 * are properly associated with this connection.
884 * @param c connection to check
887 check_neighbours (const struct CadetConnection *c)
890 return; /* nothing to check */
891 GCP_check_connection (get_next_hop (c), c);
892 GCP_check_connection (get_prev_hop (c), c);
897 * Helper for #GCC_check_connections(). Calls #check_neighbours().
901 * @param value the `struct CadetConnection` to check
902 * @return #GNUNET_OK (continue to iterate)
905 check_connection (void *cls,
906 const struct GNUNET_HashCode *key,
909 struct CadetConnection *c = value;
911 check_neighbours (c);
917 * Check invariants for all connections using #check_neighbours().
920 GCC_check_connections ()
922 if (0 == CHECK_INVARIANTS)
924 if (NULL == connections)
926 GNUNET_CONTAINER_multihashmap_iterate (connections,
933 * Get the hop in a connection.
935 * @param c Connection.
936 * @param fwd Next in the FWD direction?
938 * @return Next peer in the connection.
940 static struct CadetPeer *
941 get_hop (struct CadetConnection *c, int fwd)
943 return (fwd) ? get_next_hop (c) : get_prev_hop (c);
948 * Get a bit mask for a message received out-of-order.
950 * @param last_pid_recv Last PID we received prior to the out-of-order.
951 * @param ooo_pid PID of the out-of-order message.
954 get_recv_bitmask (uint32_t last_pid_recv, uint32_t ooo_pid)
956 return 1 << (last_pid_recv - ooo_pid);
961 * Check is an out-of-order message is ok:
962 * - at most 31 messages behind.
965 * @param last_pid_recv Last in-order PID received.
968 is_ooo_ok (uint32_t last_pid_recv, uint32_t ooo_pid, uint32_t ooo_bitmap)
972 if (GC_is_pid_bigger (last_pid_recv - 31, ooo_pid))
975 mask = get_recv_bitmask (last_pid_recv, ooo_pid);
976 if (0 != (ooo_bitmap & mask))
984 * Is traffic coming from this sender 'FWD' traffic?
986 * @param c Connection to check.
987 * @param sender Short peer identity of neighbor.
989 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
990 * the traffic is 'FWD'.
991 * #GNUNET_NO for BCK.
992 * #GNUNET_SYSERR for errors (sender isn't a hop in the connection).
995 is_fwd (const struct CadetConnection *c,
996 const struct CadetPeer *sender)
1000 id = GCP_get_short_id (sender);
1001 if (GCP_get_short_id (get_prev_hop (c)) == id)
1004 if (GCP_get_short_id (get_next_hop (c)) == id)
1007 return GNUNET_SYSERR;
1012 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
1013 * or a first CONNECTION_ACK directed to us.
1015 * @param c Connection to confirm.
1016 * @param fwd Should we send it FWD? (root->dest)
1017 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
1020 send_connection_ack (struct CadetConnection *c, int fwd)
1022 struct GNUNET_CADET_ConnectionACK msg;
1023 struct CadetTunnel *t;
1024 const uint16_t size = sizeof (struct GNUNET_CADET_ConnectionACK);
1025 const uint16_t type = GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK;
1027 GCC_check_connections ();
1029 LOG (GNUNET_ERROR_TYPE_INFO,
1030 "==> %s ({ C %s ACK} 0) on conn %s (%p) %s [%5u]\n",
1031 GC_m2s (type), GC_f2s (!fwd), GCC_2s (c), c, GC_f2s (fwd), size);
1033 msg.header.size = htons (size);
1034 msg.header.type = htons (type);
1035 msg.reserved = htonl (0);
1038 GNUNET_assert (NULL == c->maintenance_q);
1039 c->maintenance_q = GCP_send (get_hop (c, fwd), &msg.header,
1040 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK, 0,
1042 &conn_message_sent, NULL);
1043 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (conn`ACK)\n",
1044 c, c->pending_messages);
1045 c->pending_messages++;
1047 if (CADET_TUNNEL_NEW == GCT_get_cstate (t))
1048 GCT_change_cstate (t, CADET_TUNNEL_WAITING);
1049 if (CADET_CONNECTION_READY != c->state)
1050 connection_change_state (c, CADET_CONNECTION_SENT);
1051 GCC_check_connections ();
1056 * Send a notification that a connection is broken.
1058 * @param c Connection that is broken.
1059 * @param id1 Peer that has disconnected.
1060 * @param id2 Peer that has disconnected.
1061 * @param fwd Direction towards which to send it.
1064 send_broken (struct CadetConnection *c,
1065 const struct GNUNET_PeerIdentity *id1,
1066 const struct GNUNET_PeerIdentity *id2,
1069 struct GNUNET_CADET_ConnectionBroken msg;
1071 GCC_check_connections ();
1072 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1073 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1075 msg.reserved = htonl (0);
1078 (void) GCC_send_prebuilt_message (&msg.header, UINT16_MAX, 0, c, fwd,
1079 GNUNET_YES, NULL, NULL);
1080 GCC_check_connections ();
1085 * Send a notification that a connection is broken, when a connection
1086 * isn't even known to the local peer or soon to be destroyed.
1088 * @param connection_id Connection ID.
1089 * @param id1 Peer that has disconnected, probably local peer.
1090 * @param id2 Peer that has disconnected can be NULL if unknown.
1091 * @param neighbor Peer to notify (neighbor who sent the connection).
1094 send_broken_unknown (const struct GNUNET_CADET_Hash *connection_id,
1095 const struct GNUNET_PeerIdentity *id1,
1096 const struct GNUNET_PeerIdentity *id2,
1097 struct CadetPeer *neighbor)
1099 struct GNUNET_CADET_ConnectionBroken msg;
1101 GCC_check_connections ();
1102 LOG (GNUNET_ERROR_TYPE_INFO, "--> BROKEN on unknown connection %s\n",
1103 GNUNET_h2s (GC_h2hc (connection_id)));
1105 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1106 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1107 msg.cid = *connection_id;
1108 msg.reserved = htonl (0);
1113 memset (&msg.peer2, 0, sizeof (msg.peer2));
1114 GNUNET_assert (NULL != GCP_send (neighbor, &msg.header,
1116 NULL, GNUNET_SYSERR, /* connection, fwd */
1117 NULL, NULL)); /* continuation */
1118 GCC_check_connections ();
1123 * Send keepalive packets for a connection.
1125 * @param c Connection to keep alive..
1126 * @param fwd Is this a FWD keepalive? (owner -> dest).
1129 send_connection_keepalive (struct CadetConnection *c, int fwd)
1131 struct GNUNET_MessageHeader msg;
1132 struct CadetFlowControl *fc;
1135 GCC_check_connections ();
1136 LOG (GNUNET_ERROR_TYPE_INFO,
1137 "keepalive %s for connection %s\n",
1138 GC_f2s (fwd), GCC_2s (c));
1140 GNUNET_assert (NULL != c->t);
1141 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1142 tunnel_ready = GNUNET_YES == GCT_has_queued_traffic (c->t)
1143 && CADET_TUNNEL_KEY_OK <= GCT_get_estate (c->t);
1144 if (0 < fc->queue_n || tunnel_ready)
1146 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, traffic in queue\n");
1150 GNUNET_STATISTICS_update (stats, "# keepalives sent", 1, GNUNET_NO);
1152 GNUNET_assert (NULL != c->t);
1153 msg.size = htons (sizeof (msg));
1154 msg.type = htons (GNUNET_MESSAGE_TYPE_CADET_KEEPALIVE);
1156 GNUNET_assert (NULL ==
1157 GCT_send_prebuilt_message (&msg, c->t, c,
1158 GNUNET_NO, NULL, NULL));
1159 GCC_check_connections ();
1164 * Send CONNECTION_{CREATE/ACK} packets for a connection.
1166 * @param c Connection for which to send the message.
1167 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
1170 connection_recreate (struct CadetConnection *c, int fwd)
1172 LOG (GNUNET_ERROR_TYPE_DEBUG,
1173 "sending connection recreate\n");
1175 GCC_send_create (c);
1177 send_connection_ack (c, GNUNET_NO);
1182 * Generic connection timer management.
1183 * Depending on the role of the peer in the connection will send the
1184 * appropriate message (build or keepalive)
1186 * @param c Conncetion to maintain.
1187 * @param fwd Is FWD?
1190 connection_maintain (struct CadetConnection *c, int fwd)
1192 if (GNUNET_NO != c->destroy)
1194 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, being destroyed\n");
1201 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1205 if (CADET_TUNNEL_SEARCHING == GCT_get_cstate (c->t))
1207 /* If status is SEARCHING, why is there a connection? Should be WAITING */
1209 GCT_debug (c->t, GNUNET_ERROR_TYPE_ERROR);
1210 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, tunnel SEARCHING\n");
1211 schedule_next_keepalive (c, fwd);
1216 case CADET_CONNECTION_NEW:
1219 case CADET_CONNECTION_SENT:
1220 connection_recreate (c, fwd);
1222 case CADET_CONNECTION_READY:
1223 send_connection_keepalive (c, fwd);
1232 * Keep the connection alive.
1234 * @param c Connection to keep alive.
1235 * @param fwd Direction.
1238 connection_keepalive (struct CadetConnection *c,
1241 GCC_check_connections ();
1242 LOG (GNUNET_ERROR_TYPE_DEBUG,
1243 "%s keepalive for %s\n",
1244 GC_f2s (fwd), GCC_2s (c));
1247 c->fwd_maintenance_task = NULL;
1249 c->bck_maintenance_task = NULL;
1250 connection_maintain (c, fwd);
1251 GCC_check_connections ();
1252 /* Next execution will be scheduled by message_sent or _maintain*/
1257 * Keep the connection alive in the FWD direction.
1259 * @param cls Closure (connection to keepalive).
1262 connection_fwd_keepalive (void *cls)
1264 struct CadetConnection *c = cls;
1266 GCC_check_connections ();
1267 connection_keepalive (c,
1269 GCC_check_connections ();
1274 * Keep the connection alive in the BCK direction.
1276 * @param cls Closure (connection to keepalive).
1279 connection_bck_keepalive (void *cls)
1281 struct CadetConnection *c = cls;
1283 GCC_check_connections ();
1284 connection_keepalive (c,
1286 GCC_check_connections ();
1291 * Schedule next keepalive task, taking in consideration
1292 * the connection state and number of retries.
1294 * If the peer is not the origin, do nothing.
1296 * @param c Connection for which to schedule the next keepalive.
1297 * @param fwd Direction for the next keepalive.
1300 schedule_next_keepalive (struct CadetConnection *c, int fwd)
1302 struct GNUNET_TIME_Relative delay;
1303 struct GNUNET_SCHEDULER_Task * *task_id;
1304 GNUNET_SCHEDULER_TaskCallback keepalive_task;
1306 GCC_check_connections ();
1307 if (GNUNET_NO == GCC_is_origin (c, fwd))
1310 /* Calculate delay to use, depending on the state of the connection */
1311 if (CADET_CONNECTION_READY == c->state)
1313 delay = refresh_connection_time;
1317 if (1 > c->create_retry)
1318 c->create_retry = 1;
1319 delay = GNUNET_TIME_relative_multiply (create_connection_time,
1321 if (c->create_retry < 64) // TODO make configurable
1322 c->create_retry *= 2;
1325 /* Select direction-dependent parameters */
1326 if (GNUNET_YES == fwd)
1328 task_id = &c->fwd_maintenance_task;
1329 keepalive_task = &connection_fwd_keepalive;
1333 task_id = &c->bck_maintenance_task;
1334 keepalive_task = &connection_bck_keepalive;
1337 /* Check that no one scheduled it before us */
1338 if (NULL != *task_id)
1340 /* No need for a _break. It can happen for instance when sending a SYNACK
1341 * for a duplicate SYN: the first SYNACK scheduled the task. */
1342 GNUNET_SCHEDULER_cancel (*task_id);
1345 /* Schedule the task */
1346 *task_id = GNUNET_SCHEDULER_add_delayed (delay,
1349 LOG (GNUNET_ERROR_TYPE_DEBUG,
1350 "next keepalive in %s\n",
1351 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1352 GCC_check_connections ();
1357 * Cancel all transmissions that belong to a certain connection.
1359 * If the connection is scheduled for destruction and no more messages are left,
1360 * the connection will be destroyed by the continuation call.
1362 * @param c Connection which to cancel. Might be destroyed during this call.
1363 * @param fwd Cancel fwd traffic?
1366 connection_cancel_queues (struct CadetConnection *c,
1369 struct CadetFlowControl *fc;
1371 GCC_check_connections ();
1372 LOG (GNUNET_ERROR_TYPE_DEBUG,
1373 "Cancel %s queues for connection %s\n",
1374 GC_f2s (fwd), GCC_2s (c));
1381 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1382 if (NULL != fc->poll_task)
1384 GNUNET_SCHEDULER_cancel (fc->poll_task);
1385 fc->poll_task = NULL;
1386 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL task for fc %p\n", fc);
1388 if (NULL != fc->poll_msg)
1390 GCC_cancel (fc->poll_msg);
1391 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL msg for fc %p\n", fc);
1394 while (NULL != fc->q_head)
1396 GCC_cancel (fc->q_head);
1398 GCC_check_connections ();
1403 * Function called if a connection has been stalled for a while,
1404 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1406 * @param cls Closure (poll ctx).
1409 send_connection_poll (void *cls);
1413 * Callback called when a queued POLL message is sent.
1415 * @param cls Closure (flow control context).
1416 * @param c Connection this message was on.
1417 * @param q Queue handler this call invalidates.
1418 * @param type Type of message sent.
1419 * @param fwd Was this a FWD going message?
1420 * @param size Size of the message.
1423 poll_sent (void *cls,
1424 struct CadetConnection *c,
1425 struct CadetConnectionQueue *q,
1426 uint16_t type, int fwd, size_t size)
1428 struct CadetFlowControl *fc = cls;
1430 GNUNET_assert (fc->poll_msg == q);
1431 fc->poll_msg = NULL;
1432 if (2 == c->destroy)
1434 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL canceled on shutdown\n");
1437 if (0 == fc->queue_max)
1439 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL cancelled: neighbor disconnected\n");
1442 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL sent for %s, scheduling new one!\n",
1444 GNUNET_assert (NULL == fc->poll_task);
1445 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1446 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1447 &send_connection_poll,
1449 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1454 * Function called if a connection has been stalled for a while,
1455 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1457 * @param cls Closure (poll ctx).
1460 send_connection_poll (void *cls)
1462 struct CadetFlowControl *fc = cls;
1463 struct GNUNET_CADET_Poll msg;
1464 struct CadetConnection *c;
1467 fc->poll_task = NULL;
1468 GCC_check_connections ();
1470 fwd = fc == &c->fwd_fc;
1471 LOG (GNUNET_ERROR_TYPE_DEBUG, "Polling connection %s %s\n",
1472 GCC_2s (c), GC_f2s (fwd));
1474 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_POLL);
1475 msg.header.size = htons (sizeof (msg));
1477 msg.pid = htonl (fc->last_pid_sent);
1478 LOG (GNUNET_ERROR_TYPE_DEBUG, " last pid sent: %u\n", fc->last_pid_sent);
1480 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, fc->last_pid_sent, c,
1481 fc == &c->fwd_fc, GNUNET_YES, &poll_sent, fc);
1482 GNUNET_assert (NULL != fc->poll_msg);
1483 GCC_check_connections ();
1488 * Generic connection timeout implementation.
1490 * Timeout function due to lack of keepalive/traffic from an endpoint.
1491 * Destroys connection if called.
1493 * @param c Connection to destroy.
1494 * @param fwd Was the timeout from the origin? (FWD timeout)
1497 connection_timeout (struct CadetConnection *c, int fwd)
1499 GCC_check_connections ();
1501 LOG (GNUNET_ERROR_TYPE_INFO,
1502 "Connection %s %s timed out. Destroying.\n",
1505 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1507 if (GCC_is_origin (c, fwd)) /* Loopback? Something is wrong! */
1513 /* If dest, send "broken" notification. */
1514 if (GCC_is_terminal (c, fwd))
1516 struct CadetPeer *next_hop;
1518 next_hop = fwd ? get_prev_hop (c) : get_next_hop (c);
1519 send_broken_unknown (&c->id, &my_full_id, NULL, next_hop);
1523 GCC_check_connections ();
1528 * Timeout function due to lack of keepalive/traffic from the owner.
1529 * Destroys connection if called.
1531 * @param cls Closure (connection to destroy).
1534 connection_fwd_timeout (void *cls)
1536 struct CadetConnection *c = cls;
1538 c->fwd_maintenance_task = NULL;
1539 GCC_check_connections ();
1540 connection_timeout (c, GNUNET_YES);
1541 GCC_check_connections ();
1546 * Timeout function due to lack of keepalive/traffic from the destination.
1547 * Destroys connection if called.
1549 * @param cls Closure (connection to destroy).
1552 connection_bck_timeout (void *cls)
1554 struct CadetConnection *c = cls;
1556 c->bck_maintenance_task = NULL;
1557 GCC_check_connections ();
1558 connection_timeout (c, GNUNET_NO);
1559 GCC_check_connections ();
1564 * Resets the connection timeout task, some other message has done the
1566 * - For the first peer on the direction this means to send
1567 * a keepalive or a path confirmation message (either create or ACK).
1568 * - For all other peers, this means to destroy the connection,
1569 * due to lack of activity.
1570 * Starts the timeout if no timeout was running (connection just created).
1572 * @param c Connection whose timeout to reset.
1573 * @param fwd Is this forward?
1575 * TODO use heap to improve efficiency of scheduler.
1578 connection_reset_timeout (struct CadetConnection *c, int fwd)
1580 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1581 if (GCC_is_origin (c, fwd)) /* Startpoint */
1583 schedule_next_keepalive (c, fwd);
1584 if (NULL != c->maintenance_q)
1586 GCP_send_cancel (c->maintenance_q);
1587 c->maintenance_q = NULL; /* Is set to NULL by conn_message_sent anyway */
1590 else /* Relay, endpoint. */
1592 struct GNUNET_TIME_Relative delay;
1593 struct GNUNET_SCHEDULER_Task * *ti;
1594 GNUNET_SCHEDULER_TaskCallback f;
1596 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1599 GNUNET_SCHEDULER_cancel (*ti);
1600 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1601 LOG (GNUNET_ERROR_TYPE_DEBUG,
1602 " timing out in %s\n",
1603 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_NO));
1604 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1605 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1611 * Iterator to compare each connection's path with the path of a new connection.
1613 * If the connection coincides, the c member of path is set to the connection
1614 * and the destroy flag of the connection is set.
1616 * @param cls Closure (new path).
1617 * @param c Connection in the tunnel to check.
1620 check_path (void *cls, struct CadetConnection *c)
1622 struct CadetConnection *new_conn = cls;
1623 struct CadetPeerPath *path = new_conn->path;
1625 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking %s (%p), length %u\n",
1626 GCC_2s (c), c, c->path->length);
1629 && GNUNET_NO == c->destroy
1630 && CADET_CONNECTION_BROKEN != c->state
1631 && CADET_CONNECTION_DESTROYED != c->state
1632 && path_equivalent (path, c->path))
1634 new_conn->destroy = GNUNET_YES; /* Do not mark_destroyed, */
1635 new_conn->path->c = c; /* this is only a flag for the Iterator. */
1636 LOG (GNUNET_ERROR_TYPE_DEBUG, " MATCH!\n");
1642 * Finds out if this path is already being used by an existing connection.
1644 * Checks the tunnel towards the destination to see if it contains
1645 * any connection with the same path.
1647 * If the existing connection is ready, it is kept.
1648 * Otherwise if the sender has a smaller ID that ours, we accept it (and
1649 * the peer will eventually reject our attempt).
1651 * @param path Path to check.
1652 * @return #GNUNET_YES if the tunnel has a connection with the same path,
1653 * #GNUNET_NO otherwise.
1656 does_connection_exist (struct CadetConnection *conn)
1658 struct CadetPeer *p;
1659 struct CadetTunnel *t;
1660 struct CadetConnection *c;
1662 p = GCP_get_short (conn->path->peers[0], GNUNET_NO);
1665 t = GCP_get_tunnel (p);
1669 LOG (GNUNET_ERROR_TYPE_DEBUG, "Checking for duplicates\n");
1671 GCT_iterate_connections (t, &check_path, conn);
1673 if (GNUNET_YES == conn->destroy)
1676 conn->destroy = GNUNET_NO;
1677 conn->path->c = conn;
1678 LOG (GNUNET_ERROR_TYPE_DEBUG, " found duplicate of %s\n", GCC_2s (conn));
1679 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate: %s\n", GCC_2s (c));
1680 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1681 if (CADET_CONNECTION_READY == c->state)
1683 /* The other peer confirmed a live connection with this path,
1684 * why are they trying to duplicate it? */
1685 GNUNET_STATISTICS_update (stats, "# duplicate connections", 1, GNUNET_NO);
1688 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate not ready, connection unique\n");
1693 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s has no duplicates\n", GCC_2s (conn));
1700 * @brief Check if the tunnel this connection belongs to has any other
1701 * connection with the same path, and destroy one if so.
1703 * @param cls Closure (connection to check).
1706 check_duplicates (void *cls)
1708 struct CadetConnection *c = cls;
1710 c->check_duplicates_task = NULL;
1711 if (GNUNET_YES == does_connection_exist (c))
1713 GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1714 send_broken (c, &my_full_id, &my_full_id, GCC_is_origin (c, GNUNET_YES));
1721 * Wait for enough time to let any dead connections time out and check for
1722 * any remaining duplicates.
1724 * @param c Connection that is a potential duplicate.
1727 schedule_check_duplicates (struct CadetConnection *c)
1729 struct GNUNET_TIME_Relative delay;
1731 if (NULL != c->check_duplicates_task)
1733 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 5);
1734 c->check_duplicates_task = GNUNET_SCHEDULER_add_delayed (delay,
1741 * Add the connection to the list of both neighbors.
1743 * @param c Connection.
1745 * @return #GNUNET_OK if everything went fine
1746 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1749 register_neighbors (struct CadetConnection *c)
1751 c->next_peer = get_next_hop (c);
1752 c->prev_peer = get_prev_hop (c);
1753 GNUNET_assert (c->next_peer != c->prev_peer);
1754 LOG (GNUNET_ERROR_TYPE_DEBUG,
1755 "register neighbors for connection %s\n",
1757 path_debug (c->path);
1758 LOG (GNUNET_ERROR_TYPE_DEBUG,
1759 "own pos %u\n", c->own_pos);
1760 LOG (GNUNET_ERROR_TYPE_DEBUG,
1761 "putting connection %s to next peer %p\n",
1764 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n",
1766 GCP_2s (c->next_peer));
1767 LOG (GNUNET_ERROR_TYPE_DEBUG,
1768 "putting connection %s to prev peer %p\n",
1771 LOG (GNUNET_ERROR_TYPE_DEBUG,
1772 "prev peer %p %s\n",
1774 GCP_2s (c->prev_peer));
1776 if ( (GNUNET_NO == GCP_is_neighbor (c->next_peer)) ||
1777 (GNUNET_NO == GCP_is_neighbor (c->prev_peer)) )
1779 if (GCC_is_origin (c, GNUNET_YES))
1780 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1781 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1783 LOG (GNUNET_ERROR_TYPE_DEBUG,
1784 " register neighbors failed\n");
1785 LOG (GNUNET_ERROR_TYPE_DEBUG,
1786 " prev: %s, neighbor?: %d\n",
1787 GCP_2s (c->prev_peer),
1788 GCP_is_neighbor (c->prev_peer));
1789 LOG (GNUNET_ERROR_TYPE_DEBUG,
1790 " next: %s, neighbor?: %d\n",
1791 GCP_2s (c->next_peer),
1792 GCP_is_neighbor (c->next_peer));
1793 return GNUNET_SYSERR;
1795 GCP_add_connection (c->next_peer, c, GNUNET_NO);
1796 GCP_add_connection (c->prev_peer, c, GNUNET_YES);
1803 * Remove the connection from the list of both neighbors.
1805 * @param c Connection.
1808 unregister_neighbors (struct CadetConnection *c)
1810 // struct CadetPeer *peer; FIXME dont use next_peer, prev_peer
1811 /* Either already unregistered or never got registered, it's ok either way. */
1812 if (NULL == c->path)
1814 if (NULL != c->next_peer)
1816 GCP_remove_connection (c->next_peer, c);
1817 c->next_peer = NULL;
1819 if (NULL != c->prev_peer)
1821 GCP_remove_connection (c->prev_peer, c);
1822 c->prev_peer = NULL;
1828 * Invalidates all paths towards all peers that comprise the connection which
1829 * rely on the disconnected peer.
1831 * ~O(n^3) (peers in connection * paths/peer * links/path)
1833 * @param c Connection whose peers' paths to clean.
1834 * @param disconnected Peer that disconnected.
1837 invalidate_paths (struct CadetConnection *c,
1838 struct CadetPeer *disconnected)
1840 struct CadetPeer *peer;
1843 for (i = 0; i < c->path->length; i++)
1845 peer = GCP_get_short (c->path->peers[i], GNUNET_NO);
1847 GCP_notify_broken_link (peer, &my_full_id, GCP_get_id (disconnected));
1853 * Bind the connection to the peer and the tunnel to that peer.
1855 * If the peer has no tunnel, create one. Update tunnel and connection
1856 * data structres to reflect new status.
1858 * @param c Connection.
1862 add_to_peer (struct CadetConnection *c,
1863 struct CadetPeer *peer)
1865 GCP_add_tunnel (peer);
1866 c->t = GCP_get_tunnel (peer);
1867 GCT_add_connection (c->t, c);
1872 * Log receipt of message on stderr (INFO level).
1874 * @param message Message received.
1875 * @param peer Peer who sent the message.
1876 * @param conn_id Connection ID of the message.
1879 log_message (const struct GNUNET_MessageHeader *message,
1880 const struct CadetPeer *peer,
1881 const struct GNUNET_CADET_Hash *conn_id)
1887 size = ntohs (message->size);
1888 type = ntohs (message->type);
1891 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
1892 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
1893 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
1894 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
1900 LOG (GNUNET_ERROR_TYPE_INFO, "<%s %s on conn %s from %s, %6u bytes\n",
1901 arrow, GC_m2s (type), GNUNET_h2s (GC_h2hc (conn_id)),
1902 GCP_2s(peer), (unsigned int) size);
1905 /******************************************************************************/
1906 /******************************** API ***********************************/
1907 /******************************************************************************/
1910 * Handler for connection creation.
1912 * @param peer Message sender (neighbor).
1913 * @param msg Message itself.
1916 GCC_handle_create (struct CadetPeer *peer,
1917 const struct GNUNET_CADET_ConnectionCreate *msg)
1919 const struct GNUNET_CADET_Hash *cid;
1920 struct GNUNET_PeerIdentity *id;
1921 struct CadetPeerPath *path;
1922 struct CadetPeer *dest_peer;
1923 struct CadetPeer *orig_peer;
1924 struct CadetConnection *c;
1925 unsigned int own_pos;
1928 GCC_check_connections ();
1929 size = ntohs (msg->header.size);
1931 /* Calculate hops */
1932 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
1933 if (0 != size % sizeof (struct GNUNET_PeerIdentity))
1935 GNUNET_break_op (0);
1938 size /= sizeof (struct GNUNET_PeerIdentity);
1941 GNUNET_break_op (0);
1944 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1946 /* Get parameters */
1948 log_message (&msg->header, peer, cid);
1949 id = (struct GNUNET_PeerIdentity *) &msg[1];
1950 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
1952 /* Create connection */
1953 c = connection_get (cid);
1956 path = path_build_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
1957 size, myid, &own_pos);
1960 /* Path was malformed, probably our own ID was not in it. */
1961 GNUNET_STATISTICS_update (stats, "# malformed paths", 1, GNUNET_NO);
1962 GNUNET_break_op (0);
1967 /* We received this request from a neighbor, we cannot be origin */
1968 GNUNET_STATISTICS_update (stats, "# fake paths", 1, GNUNET_NO);
1969 GNUNET_break_op (0);
1970 path_destroy (path);
1974 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1975 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1976 c = GCC_new (cid, NULL, path, own_pos);
1979 if (path->length - 1 == own_pos)
1981 /* If we are destination, why did the creation fail? */
1983 path_destroy (path);
1984 GCC_check_connections ();
1987 send_broken_unknown (cid, &my_full_id,
1988 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
1990 path_destroy (path);
1991 GCC_check_connections ();
1994 GCP_add_path_to_all (path, GNUNET_NO);
1995 connection_reset_timeout (c, GNUNET_YES);
1999 path = path_duplicate (c->path);
2001 if (CADET_CONNECTION_NEW == c->state)
2002 connection_change_state (c, CADET_CONNECTION_SENT);
2004 /* Remember peers */
2005 dest_peer = GCP_get (&id[size - 1], GNUNET_YES);
2006 orig_peer = GCP_get (&id[0], GNUNET_YES);
2008 /* Is it a connection to us? */
2009 if (c->own_pos == path->length - 1)
2011 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
2012 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
2014 add_to_peer (c, orig_peer);
2015 if (GNUNET_YES == does_connection_exist (c))
2017 /* Peer created a connection equal to one we think exists
2019 * Solution: Keep both and postpone disambiguation. In the meantime
2020 * the connection will time out or peer will inform us it is broken.
2023 * - Use explicit duplicate.
2024 * - Accept new conn and destroy the old. (interruption in higher level)
2025 * - Keep the one with higher ID / created by peer with higher ID. */
2026 schedule_check_duplicates (c);
2029 if (CADET_TUNNEL_NEW == GCT_get_cstate (c->t))
2030 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
2031 if (NULL == c->maintenance_q)
2032 send_connection_ack (c, GNUNET_NO);
2033 if (CADET_CONNECTION_SENT == c->state)
2034 connection_change_state (c, CADET_CONNECTION_ACK);
2038 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2039 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
2040 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
2041 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c,
2042 GNUNET_YES, GNUNET_YES, NULL, NULL);
2044 path_destroy (path);
2045 GCC_check_connections ();
2050 * Handler for connection confirmations.
2052 * @param peer Message sender (neighbor).
2053 * @param msg Message itself.
2056 GCC_handle_confirm (struct CadetPeer *peer,
2057 const struct GNUNET_CADET_ConnectionACK *msg)
2059 struct CadetConnection *c;
2060 enum CadetConnectionState oldstate;
2063 GCC_check_connections ();
2064 log_message (&msg->header, peer, &msg->cid);
2065 c = connection_get (&msg->cid);
2068 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
2070 LOG (GNUNET_ERROR_TYPE_DEBUG,
2071 " don't know the connection!\n");
2072 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2073 GCC_check_connections ();
2076 if (GNUNET_NO != c->destroy)
2078 GNUNET_assert (CADET_CONNECTION_DESTROYED == c->state);
2079 GNUNET_STATISTICS_update (stats, "# control on dying connection",
2081 LOG (GNUNET_ERROR_TYPE_DEBUG,
2082 "connection %s being destroyed, ignoring confirm\n",
2084 GCC_check_connections ();
2088 oldstate = c->state;
2089 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GCP_2s (peer));
2090 if (get_next_hop (c) == peer)
2092 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
2094 if (CADET_CONNECTION_SENT == oldstate)
2095 connection_change_state (c, CADET_CONNECTION_ACK);
2097 else if (get_prev_hop (c) == peer)
2099 LOG (GNUNET_ERROR_TYPE_DEBUG, " FINAL ACK\n");
2101 connection_change_state (c, CADET_CONNECTION_READY);
2105 GNUNET_STATISTICS_update (stats, "# control on connection from wrong peer",
2107 GNUNET_break_op (0);
2111 connection_reset_timeout (c, fwd);
2113 GNUNET_assert (NULL != c->path);
2114 GCP_add_path_to_all (c->path, GNUNET_YES);
2116 /* Message for us as creator? */
2117 if (GNUNET_YES == GCC_is_origin (c, GNUNET_YES))
2119 if (GNUNET_NO != fwd)
2124 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
2126 /* If just created, cancel the short timeout and start a long one */
2127 if (CADET_CONNECTION_SENT == oldstate)
2129 c->create_retry = 1;
2130 connection_reset_timeout (c, GNUNET_YES);
2133 /* Change connection state, send ACK */
2134 connection_change_state (c, CADET_CONNECTION_READY);
2135 send_connection_ack (c, GNUNET_YES);
2137 /* Change tunnel state, trigger KX */
2138 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2139 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2140 GCC_check_connections ();
2144 /* Message for us as destination? */
2145 if (GCC_is_terminal (c, GNUNET_YES))
2147 if (GNUNET_YES != fwd)
2152 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
2154 /* If just created, cancel the short timeout and start a long one */
2155 if (CADET_CONNECTION_ACK == oldstate)
2156 connection_reset_timeout (c, GNUNET_NO);
2158 /* Change tunnel state */
2159 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2160 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2161 GCC_check_connections ();
2165 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2166 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2167 GNUNET_YES, NULL, NULL);
2169 GCC_check_connections ();
2174 * Handler for notifications of broken connections.
2176 * @param peer Message sender (neighbor).
2177 * @param msg Message itself.
2180 GCC_handle_broken (struct CadetPeer *peer,
2181 const struct GNUNET_CADET_ConnectionBroken *msg)
2183 struct CadetConnection *c;
2184 struct CadetTunnel *t;
2187 GCC_check_connections ();
2188 log_message (&msg->header, peer, &msg->cid);
2189 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n", GNUNET_i2s (&msg->peer1));
2190 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n", GNUNET_i2s (&msg->peer2));
2191 c = connection_get (&msg->cid);
2194 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
2195 GNUNET_STATISTICS_update (stats, "# duplicate CONNECTION_BROKEN",
2197 GCC_check_connections ();
2203 fwd = is_fwd (c, peer);
2204 if (GNUNET_SYSERR == fwd)
2206 GNUNET_break_op (0);
2207 GCC_check_connections ();
2211 if (GCC_is_terminal (c, fwd))
2213 struct CadetPeer *endpoint;
2217 /* A terminal connection should not have 't' set to NULL. */
2219 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
2222 endpoint = GCP_get_short (c->path->peers[c->path->length - 1], GNUNET_YES);
2223 if (2 < c->path->length)
2224 path_invalidate (c->path);
2225 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
2227 connection_change_state (c, CADET_CONNECTION_BROKEN);
2228 GCT_remove_connection (t, c);
2235 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2236 GNUNET_YES, NULL, NULL);
2237 connection_cancel_queues (c, !fwd);
2239 GCC_check_connections ();
2245 * Handler for notifications of destroyed connections.
2247 * @param peer Message sender (neighbor).
2248 * @param msg Message itself.
2251 GCC_handle_destroy (struct CadetPeer *peer,
2252 const struct GNUNET_CADET_ConnectionDestroy *msg)
2254 struct CadetConnection *c;
2257 GCC_check_connections ();
2258 log_message (&msg->header, peer, &msg->cid);
2259 c = connection_get (&msg->cid);
2262 /* Probably already got the message from another path,
2263 * destroyed the tunnel and retransmitted to children.
2266 GNUNET_STATISTICS_update (stats,
2267 "# control on unknown connection",
2269 LOG (GNUNET_ERROR_TYPE_DEBUG,
2270 " connection unknown destroyed: previously destroyed?\n");
2271 GCC_check_connections ();
2275 fwd = is_fwd (c, peer);
2276 if (GNUNET_SYSERR == fwd)
2278 GNUNET_break_op (0);
2279 GCC_check_connections ();
2283 if (GNUNET_NO == GCC_is_terminal (c, fwd))
2285 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2286 GNUNET_YES, NULL, NULL);
2288 else if (0 == c->pending_messages)
2290 LOG (GNUNET_ERROR_TYPE_DEBUG, " directly destroying connection!\n");
2292 GCC_check_connections ();
2298 GCT_remove_connection (c->t, c);
2301 GCC_check_connections ();
2307 * Handler for cadet network traffic hop-by-hop acks.
2309 * @param peer Message sender (neighbor).
2310 * @param msg Message itself.
2313 GCC_handle_ack (struct CadetPeer *peer,
2314 const struct GNUNET_CADET_ACK *msg)
2316 struct CadetConnection *c;
2317 struct CadetFlowControl *fc;
2321 GCC_check_connections ();
2322 log_message (&msg->header, peer, &msg->cid);
2323 c = connection_get (&msg->cid);
2326 GNUNET_STATISTICS_update (stats,
2327 "# ack on unknown connection",
2330 send_broken_unknown (&msg->cid,
2334 GCC_check_connections ();
2338 /* Is this a forward or backward ACK? */
2339 if (get_next_hop (c) == peer)
2344 else if (get_prev_hop (c) == peer)
2351 GNUNET_break_op (0);
2355 ack = ntohl (msg->ack);
2356 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s ACK %u (was %u)\n",
2357 GC_f2s (fwd), ack, fc->last_ack_recv);
2358 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2359 fc->last_ack_recv = ack;
2361 /* Cancel polling if the ACK is big enough. */
2362 if (NULL != fc->poll_task &&
2363 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2365 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2366 GNUNET_SCHEDULER_cancel (fc->poll_task);
2367 fc->poll_task = NULL;
2368 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2371 GCC_check_connections ();
2376 * Handler for cadet network traffic hop-by-hop data counter polls.
2378 * @param peer Message sender (neighbor).
2379 * @param msg Message itself.
2382 GCC_handle_poll (struct CadetPeer *peer,
2383 const struct GNUNET_CADET_Poll *msg)
2385 struct CadetConnection *c;
2386 struct CadetFlowControl *fc;
2390 GCC_check_connections ();
2391 log_message (&msg->header, peer, &msg->cid);
2392 c = connection_get (&msg->cid);
2395 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2397 LOG (GNUNET_ERROR_TYPE_DEBUG,
2398 "POLL message on unknown connection %s!\n",
2399 GNUNET_h2s (GC_h2hc (&msg->cid)));
2400 send_broken_unknown (&msg->cid,
2404 GCC_check_connections ();
2408 /* Is this a forward or backward ACK?
2409 * Note: a poll should never be needed in a loopback case,
2410 * since there is no possiblility of packet loss there, so
2411 * this way of discerining FWD/BCK should not be a problem.
2413 if (get_next_hop (c) == peer)
2415 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2418 else if (get_prev_hop (c) == peer)
2420 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2425 GNUNET_break_op (0);
2429 pid = ntohl (msg->pid);
2430 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2431 fc->last_pid_recv = pid;
2432 fwd = fc == &c->bck_fc;
2433 GCC_send_ack (c, fwd, GNUNET_YES);
2434 GCC_check_connections ();
2439 * Check the message against internal state and test if it goes FWD or BCK.
2441 * Updates the PID, state and timeout values for the connection.
2443 * @param message Message to check. It must belong to an existing connection.
2444 * @param cid Connection ID (even if @a c is NULL, the ID is still needed).
2445 * @param c Connection this message should belong. If NULL, check fails.
2446 * @param sender Neighbor that sent the message.
2448 * @return #GNUNET_YES if the message goes FWD.
2449 * #GNUNET_NO if it goes BCK.
2450 * #GNUNET_SYSERR if there is an error (unauthorized sender, ...).
2453 check_message (const struct GNUNET_MessageHeader *message,
2454 const struct GNUNET_CADET_Hash* cid,
2455 struct CadetConnection *c,
2456 struct CadetPeer *sender,
2459 struct CadetFlowControl *fc;
2460 struct CadetPeer *hop;
2464 /* Check connection */
2467 GNUNET_STATISTICS_update (stats,
2468 "# unknown connection",
2470 LOG (GNUNET_ERROR_TYPE_DEBUG,
2471 "%s on unknown connection %s\n",
2472 GC_m2s (ntohs (message->type)),
2473 GNUNET_h2s (GC_h2hc (cid)));
2474 send_broken_unknown (cid,
2478 return GNUNET_SYSERR;
2481 /* Check if origin is as expected */
2482 hop = get_prev_hop (c);
2489 hop = get_next_hop (c);
2490 GNUNET_break (hop == c->next_peer);
2497 /* Unexpected peer sending traffic on a connection. */
2498 GNUNET_break_op (0);
2499 return GNUNET_SYSERR;
2503 /* Check PID for payload messages */
2504 type = ntohs (message->type);
2505 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
2507 fc = fwd ? &c->bck_fc : &c->fwd_fc;
2508 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u - %u)\n",
2509 pid, fc->last_pid_recv + 1, fc->last_ack_sent);
2510 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
2512 GNUNET_break_op (0);
2513 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
2514 LOG (GNUNET_ERROR_TYPE_WARNING, "Received PID %u, (prev %u), ACK %u\n",
2515 pid, fc->last_pid_recv, fc->last_ack_sent);
2516 return GNUNET_SYSERR;
2518 if (GC_is_pid_bigger (pid, fc->last_pid_recv))
2522 delta = pid - fc->last_pid_recv;
2523 fc->last_pid_recv = pid;
2524 fc->recv_bitmap <<= delta;
2525 fc->recv_bitmap |= 1;
2529 GNUNET_STATISTICS_update (stats, "# out of order PID", 1, GNUNET_NO);
2530 if (GNUNET_NO == is_ooo_ok (fc->last_pid_recv, pid, fc->recv_bitmap))
2532 LOG (GNUNET_ERROR_TYPE_WARNING, "PID %u unexpected (%u+), dropping!\n",
2533 pid, fc->last_pid_recv - 31);
2534 return GNUNET_SYSERR;
2536 fc->recv_bitmap |= get_recv_bitmask (fc->last_pid_recv, pid);
2540 /* Count as connection confirmation. */
2541 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2543 connection_change_state (c, CADET_CONNECTION_READY);
2546 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2547 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2550 connection_reset_timeout (c, fwd);
2557 * Handler for key exchange traffic (Axolotl KX).
2559 * @param peer Message sender (neighbor).
2560 * @param msg Message itself.
2563 GCC_handle_kx (struct CadetPeer *peer,
2564 const struct GNUNET_CADET_KX *msg)
2566 const struct GNUNET_CADET_Hash* cid;
2567 struct CadetConnection *c;
2570 GCC_check_connections ();
2572 log_message (&msg->header, peer, cid);
2574 c = connection_get (cid);
2575 fwd = check_message (&msg->header,
2581 /* If something went wrong, discard message. */
2582 if (GNUNET_SYSERR == fwd)
2584 GNUNET_break_op (0);
2585 GCC_check_connections ();
2589 /* Is this message for us? */
2590 if (GCC_is_terminal (c, fwd))
2592 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2593 GNUNET_STATISTICS_update (stats, "# received KX", 1, GNUNET_NO);
2599 GCT_handle_kx (c->t, msg);
2600 GCC_check_connections ();
2604 /* Message not for us: forward to next hop */
2605 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2606 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2607 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2608 GNUNET_NO, NULL, NULL);
2609 GCC_check_connections ();
2614 * Handler for encrypted cadet network traffic (channel mgmt, data).
2616 * @param peer Message sender (neighbor).
2617 * @param msg Message itself.
2620 GCC_handle_encrypted (struct CadetPeer *peer,
2621 const struct GNUNET_CADET_Encrypted *msg)
2623 const struct GNUNET_CADET_Hash* cid;
2624 struct CadetConnection *c;
2628 GCC_check_connections ();
2630 pid = ntohl (msg->pid);
2631 log_message (&msg->header, peer, cid);
2633 c = connection_get (cid);
2634 fwd = check_message (&msg->header,
2640 /* If something went wrong, discard message. */
2641 if (GNUNET_SYSERR == fwd)
2643 GNUNET_break_op (0);
2644 GCC_check_connections ();
2648 /* Is this message for us? */
2649 if (GCC_is_terminal (c, fwd))
2651 GNUNET_STATISTICS_update (stats, "# received encrypted", 1, GNUNET_NO);
2655 GNUNET_break (GNUNET_NO != c->destroy);
2658 GCT_handle_encrypted (c->t, msg);
2659 GCC_send_ack (c, fwd, GNUNET_NO);
2660 GCC_check_connections ();
2664 /* Message not for us: forward to next hop */
2665 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2666 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2667 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2668 GNUNET_NO, NULL, NULL);
2669 GCC_check_connections ();
2674 * Initialize the connections subsystem
2676 * @param c Configuration handle.
2679 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2681 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2683 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2686 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2687 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2688 GNUNET_SCHEDULER_shutdown ();
2693 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2696 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2697 "CADET", "MAX_CONNECTIONS", "MISSING");
2698 GNUNET_SCHEDULER_shutdown ();
2703 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2704 &refresh_connection_time))
2706 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2707 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2708 GNUNET_SCHEDULER_shutdown ();
2711 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2712 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2717 * Destroy each connection on shutdown.
2719 * @param cls Closure (unused).
2720 * @param key Current key code (CID, unused).
2721 * @param value Value in the hash map (`struct CadetConnection`)
2723 * @return #GNUNET_YES, because we should continue to iterate
2726 shutdown_iterator (void *cls,
2727 const struct GNUNET_HashCode *key,
2730 struct CadetConnection *c = value;
2732 c->state = CADET_CONNECTION_DESTROYED;
2739 * Shut down the connections subsystem.
2744 LOG (GNUNET_ERROR_TYPE_DEBUG, "Shutting down connections\n");
2745 GCC_check_connections ();
2746 GNUNET_CONTAINER_multihashmap_iterate (connections,
2749 GNUNET_CONTAINER_multihashmap_destroy (connections);
2755 * Create a connection.
2757 * @param cid Connection ID (either created locally or imposed remotely).
2758 * @param t Tunnel this connection belongs to (or NULL for transit connections);
2759 * @param path Path this connection has to use (copy is made).
2760 * @param own_pos Own position in the @c path path.
2762 * @return Newly created connection.
2763 * NULL in case of error: own id not in path, wrong neighbors, ...
2765 struct CadetConnection *
2766 GCC_new (const struct GNUNET_CADET_Hash *cid,
2767 struct CadetTunnel *t,
2768 struct CadetPeerPath *path,
2769 unsigned int own_pos)
2771 struct CadetConnection *c;
2772 struct CadetPeerPath *cpath;
2774 GCC_check_connections ();
2775 cpath = path_duplicate (path);
2776 GNUNET_assert (NULL != cpath);
2777 c = GNUNET_new (struct CadetConnection);
2779 GNUNET_assert (GNUNET_OK ==
2780 GNUNET_CONTAINER_multihashmap_put (connections,
2782 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2783 fc_init (&c->fwd_fc);
2784 fc_init (&c->bck_fc);
2789 GNUNET_assert (own_pos <= cpath->length - 1);
2790 c->own_pos = own_pos;
2793 if (GNUNET_OK != register_neighbors (c))
2797 /* We were the origin of this request, this means we have invalid
2798 * info about the paths to reach the destination. We must invalidate
2799 * the *original* path to avoid trying it again in the next minute.
2801 if (2 < path->length)
2802 path_invalidate (path);
2806 GCT_debug(t, GNUNET_ERROR_TYPE_WARNING);
2810 path_destroy (c->path);
2815 LOG (GNUNET_ERROR_TYPE_INFO, "New connection %s\n", GCC_2s (c));
2816 GCC_check_connections ();
2822 * Connection is no longer needed: destroy it.
2824 * Cancels all pending traffic (including possible DESTROY messages), all
2825 * maintenance tasks and removes the connection from neighbor peers and tunnel.
2827 * @param c Connection to destroy.
2830 GCC_destroy (struct CadetConnection *c)
2832 GCC_check_connections ();
2839 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
2840 return; /* -> message_sent -> GCC_destroy. Don't loop. */
2843 LOG (GNUNET_ERROR_TYPE_DEBUG,
2844 "destroying connection %s\n",
2846 LOG (GNUNET_ERROR_TYPE_DEBUG,
2847 " fc's f: %p, b: %p\n",
2848 &c->fwd_fc, &c->bck_fc);
2849 LOG (GNUNET_ERROR_TYPE_DEBUG,
2850 " fc tasks f: %u, b: %u\n",
2851 c->fwd_fc.poll_task,
2852 c->bck_fc.poll_task);
2854 /* Cancel all traffic */
2855 if (NULL != c->path)
2857 connection_cancel_queues (c, GNUNET_YES);
2858 connection_cancel_queues (c, GNUNET_NO);
2859 if (NULL != c->maintenance_q)
2861 GCP_send_cancel (c->maintenance_q);
2862 c->maintenance_q = NULL;
2865 unregister_neighbors (c);
2866 path_destroy (c->path);
2869 /* Delete from tunnel */
2871 GCT_remove_connection (c->t, c);
2873 if (NULL != c->check_duplicates_task)
2874 GNUNET_SCHEDULER_cancel (c->check_duplicates_task);
2875 if (NULL != c->fwd_maintenance_task)
2876 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2877 if (NULL != c->bck_maintenance_task)
2878 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2880 if (GNUNET_NO == c->was_removed)
2882 GNUNET_break (GNUNET_YES ==
2883 GNUNET_CONTAINER_multihashmap_remove (connections,
2887 GNUNET_STATISTICS_update (stats,
2892 GCC_check_connections ();
2897 * Get the connection ID.
2899 * @param c Connection to get the ID from.
2901 * @return ID of the connection.
2903 const struct GNUNET_CADET_Hash *
2904 GCC_get_id (const struct CadetConnection *c)
2911 * Get the connection ID.
2913 * @param c Connection to get the ID from.
2915 * @return ID of the connection.
2917 const struct GNUNET_HashCode *
2918 GCC_get_h (const struct CadetConnection *c)
2920 return GC_h2hc (&c->id);
2925 * Get the connection path.
2927 * @param c Connection to get the path from.
2929 * @return path used by the connection.
2931 const struct CadetPeerPath *
2932 GCC_get_path (const struct CadetConnection *c)
2934 if (GNUNET_NO == c->destroy)
2941 * Get the connection state.
2943 * @param c Connection to get the state from.
2945 * @return state of the connection.
2947 enum CadetConnectionState
2948 GCC_get_state (const struct CadetConnection *c)
2954 * Get the connection tunnel.
2956 * @param c Connection to get the tunnel from.
2958 * @return tunnel of the connection.
2960 struct CadetTunnel *
2961 GCC_get_tunnel (const struct CadetConnection *c)
2968 * Get free buffer space in a connection.
2970 * @param c Connection.
2971 * @param fwd Is query about FWD traffic?
2973 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2976 GCC_get_buffer (struct CadetConnection *c, int fwd)
2978 struct CadetFlowControl *fc;
2980 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2982 LOG (GNUNET_ERROR_TYPE_DEBUG, " Get %s buffer on %s: %u - %u\n",
2983 GC_f2s (fwd), GCC_2s (c), fc->queue_max, fc->queue_n);
2984 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
2986 return (fc->queue_max - fc->queue_n);
2991 * Get how many messages have we allowed to send to us from a direction.
2993 * @param c Connection.
2994 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2996 * @return last_ack_sent - last_pid_recv
2999 GCC_get_allowed (struct CadetConnection *c, int fwd)
3001 struct CadetFlowControl *fc;
3003 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3004 if (CADET_CONNECTION_READY != c->state
3005 || GC_is_pid_bigger (fc->last_pid_recv, fc->last_ack_sent))
3009 return (fc->last_ack_sent - fc->last_pid_recv);
3014 * Get messages queued in a connection.
3016 * @param c Connection.
3017 * @param fwd Is query about FWD traffic?
3019 * @return Number of messages queued.
3022 GCC_get_qn (struct CadetConnection *c, int fwd)
3024 struct CadetFlowControl *fc;
3026 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3033 * Get next PID to use.
3035 * @param c Connection.
3036 * @param fwd Is query about FWD traffic?
3038 * @return Next PID to use.
3041 GCC_get_pid (struct CadetConnection *c, int fwd)
3043 struct CadetFlowControl *fc;
3046 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3054 * Allow the connection to advertise a buffer of the given size.
3056 * The connection will send an @c fwd ACK message (so: in direction !fwd)
3057 * allowing up to last_pid_recv + buffer.
3059 * @param c Connection.
3060 * @param buffer How many more messages the connection can accept.
3061 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
3064 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
3066 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
3067 GCC_2s (c), buffer, GC_f2s (fwd));
3068 send_ack (c, buffer, fwd, GNUNET_NO);
3073 * Notify other peers on a connection of a broken link. Mark connections
3074 * to destroy after all traffic has been sent.
3076 * @param c Connection on which there has been a disconnection.
3077 * @param peer Peer that disconnected.
3080 GCC_neighbor_disconnected (struct CadetConnection *c, struct CadetPeer *peer)
3082 struct CadetFlowControl *fc;
3086 GCC_check_connections ();
3087 strncpy (peer_name, GCP_2s (peer), 16);
3088 peer_name[15] = '\0';
3089 LOG (GNUNET_ERROR_TYPE_DEBUG,
3090 "shutting down %s, %s disconnected\n",
3091 GCC_2s (c), peer_name);
3093 invalidate_paths (c, peer);
3095 fwd = is_fwd (c, peer);
3096 if (GNUNET_SYSERR == fwd)
3101 if ( (GNUNET_YES == GCC_is_terminal (c, fwd)) ||
3102 (GNUNET_NO != c->destroy) )
3104 /* Local shutdown, or other peer already down (hence 'c->destroy');
3105 so there is no one to notify about this, just clean up. */
3107 GCC_check_connections ();
3110 /* Mark FlowControl towards the peer as unavaliable. */
3111 fc = fwd ? &c->bck_fc : &c->fwd_fc;
3114 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
3116 /* Connection will have at least one pending message
3117 * (the one we just scheduled), so delay destruction
3118 * and remove from map so we don't use accidentally. */
3120 GNUNET_assert (GNUNET_NO == c->was_removed);
3121 c->was_removed = GNUNET_YES;
3122 GNUNET_break (GNUNET_YES ==
3123 GNUNET_CONTAINER_multihashmap_remove (connections,
3126 /* Cancel queue in the direction that just died. */
3127 connection_cancel_queues (c, ! fwd);
3128 GCC_stop_poll (c, ! fwd);
3129 unregister_neighbors (c);
3130 GCC_check_connections ();
3135 * Is this peer the first one on the connection?
3137 * @param c Connection.
3138 * @param fwd Is this about fwd traffic?
3140 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
3143 GCC_is_origin (struct CadetConnection *c, int fwd)
3145 if (!fwd && c->path->length - 1 == c->own_pos )
3147 if (fwd && 0 == c->own_pos)
3154 * Is this peer the last one on the connection?
3156 * @param c Connection.
3157 * @param fwd Is this about fwd traffic?
3158 * Note that the ROOT is the terminal for BCK traffic!
3160 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
3163 GCC_is_terminal (struct CadetConnection *c, int fwd)
3165 return GCC_is_origin (c, ! fwd);
3170 * See if we are allowed to send by the next hop in the given direction.
3172 * @param c Connection.
3173 * @param fwd Is this about fwd traffic?
3175 * @return #GNUNET_YES in case it's OK to send.
3178 GCC_is_sendable (struct CadetConnection *c, int fwd)
3180 struct CadetFlowControl *fc;
3182 LOG (GNUNET_ERROR_TYPE_DEBUG,
3183 " checking sendability of %s traffic on %s\n",
3184 GC_f2s (fwd), GCC_2s (c));
3190 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3191 LOG (GNUNET_ERROR_TYPE_DEBUG,
3192 " last ack recv: %u, last pid sent: %u\n",
3193 fc->last_ack_recv, fc->last_pid_sent);
3194 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
3196 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
3199 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
3205 * Check if this connection is a direct one (never trim a direct connection).
3207 * @param c Connection.
3209 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
3212 GCC_is_direct (struct CadetConnection *c)
3214 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
3219 * Sends a completely built message on a connection, properly registering
3220 * all used resources.
3222 * @param message Message to send.
3223 * @param payload_type Type of payload, in case the message is encrypted.
3224 * 0 for restransmissions (when type is no longer known)
3225 * UINT16_MAX when not applicable.
3226 * @param payload_id ID of the payload (PID, ACK, ...).
3227 * @param c Connection on which this message is transmitted.
3228 * @param fwd Is this a fwd message?
3229 * @param force Force the connection to accept the message (buffer overfill).
3230 * @param cont Continuation called once message is sent. Can be NULL.
3231 * @param cont_cls Closure for @c cont.
3233 * @return Handle to cancel the message before it's sent.
3234 * NULL on error or if @c cont is NULL.
3235 * Invalid on @c cont call.
3237 struct CadetConnectionQueue *
3238 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
3239 uint16_t payload_type, uint32_t payload_id,
3240 struct CadetConnection *c, int fwd, int force,
3241 GCC_sent cont, void *cont_cls)
3243 struct CadetFlowControl *fc;
3244 struct CadetConnectionQueue *q;
3248 size = ntohs (message->size);
3249 type = ntohs (message->type);
3251 GCC_check_connections ();
3252 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3253 if (0 == fc->queue_max)
3259 LOG (GNUNET_ERROR_TYPE_INFO,
3260 "--> %s (%s %4u) on conn %s (%p) %s [%5u]\n",
3261 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), c,
3265 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
3266 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
3267 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
3268 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
3269 if (GNUNET_NO == force)
3275 case GNUNET_MESSAGE_TYPE_CADET_KX:
3278 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
3279 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
3280 /* Should've only be used for restransmissions. */
3281 GNUNET_break (0 == payload_type);
3284 case GNUNET_MESSAGE_TYPE_CADET_ACK:
3285 case GNUNET_MESSAGE_TYPE_CADET_POLL:
3286 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
3287 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
3288 GNUNET_assert (GNUNET_YES == force);
3296 if (fc->queue_n > fc->queue_max && GNUNET_NO == force)
3298 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
3301 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue full: %u/%u\n",
3302 fc->queue_n, fc->queue_max);
3303 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
3307 return NULL; /* Drop this message */
3310 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %s %u\n",
3311 GCC_2s (c), c->pending_messages);
3312 c->pending_messages++;
3314 q = GNUNET_new (struct CadetConnectionQueue);
3316 q->peer_q = GCP_send (get_hop (c, fwd), message,
3317 payload_type, payload_id,
3319 &conn_message_sent, q);
3320 if (NULL == q->peer_q)
3322 LOG (GNUNET_ERROR_TYPE_DEBUG, "dropping msg on %s, NULL q\n", GCC_2s (c));
3324 GCC_check_connections ();
3328 q->cont_cls = cont_cls;
3329 GNUNET_CONTAINER_DLL_insert (fc->q_head, fc->q_tail, q);
3330 GCC_check_connections ();
3336 * Cancel a previously sent message while it's in the queue.
3338 * ONLY can be called before the continuation given to the send function
3339 * is called. Once the continuation is called, the message is no longer in the
3342 * @param q Handle to the queue.
3345 GCC_cancel (struct CadetConnectionQueue *q)
3347 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GCC cancel message\n");
3349 /* send_cancel calls message_sent, which calls q->cont and frees q */
3350 GCP_send_cancel (q->peer_q);
3351 GCC_check_connections ();
3356 * Sends a CREATE CONNECTION message for a path to a peer.
3357 * Changes the connection and tunnel states if necessary.
3359 * @param c Connection to create.
3362 GCC_send_create (struct CadetConnection *c)
3364 enum CadetTunnelCState state;
3367 GCC_check_connections ();
3368 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3369 size += c->path->length * sizeof (struct GNUNET_PeerIdentity);
3371 /* Allocate message on the stack */
3372 unsigned char cbuf[size];
3373 struct GNUNET_CADET_ConnectionCreate *msg;
3374 struct GNUNET_PeerIdentity *peers;
3376 msg = (struct GNUNET_CADET_ConnectionCreate *) cbuf;
3377 msg->header.size = htons (size);
3378 msg->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE);
3379 msg->reserved = htonl (0);
3380 msg->cid = *GCC_get_id (c);
3381 peers = (struct GNUNET_PeerIdentity *) &msg[1];
3382 for (int i = 0; i < c->path->length; i++)
3384 GNUNET_PEER_resolve (c->path->peers[i], peers++);
3386 GNUNET_assert (NULL == c->maintenance_q);
3387 c->maintenance_q = GCP_send (get_next_hop (c),
3389 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, 0,
3391 &conn_message_sent, NULL);
3394 LOG (GNUNET_ERROR_TYPE_INFO, "==> %s %19s on conn %s (%p) FWD [%5u]\n",
3395 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE), "",
3396 GCC_2s (c), c, size);
3397 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3398 c, c->pending_messages);
3399 c->pending_messages++;
3401 state = GCT_get_cstate (c->t);
3402 if (CADET_TUNNEL_SEARCHING == state || CADET_TUNNEL_NEW == state)
3403 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
3404 if (CADET_CONNECTION_NEW == c->state)
3405 connection_change_state (c, CADET_CONNECTION_SENT);
3406 GCC_check_connections ();
3411 * Send an ACK on the appropriate connection/channel, depending on
3412 * the direction and the position of the peer.
3414 * @param c Which connection to send the hop-by-hop ACK.
3415 * @param fwd Is this a fwd ACK? (will go dest->root).
3416 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
3419 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
3421 unsigned int buffer;
3423 GCC_check_connections ();
3424 LOG (GNUNET_ERROR_TYPE_DEBUG, "GCC send %s ACK on %s\n",
3425 GC_f2s (fwd), GCC_2s (c));
3433 if (GNUNET_NO != c->destroy)
3435 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
3436 GCC_check_connections ();
3440 /* Get available buffer space */
3441 if (GCC_is_terminal (c, fwd))
3443 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
3444 buffer = GCT_get_channels_buffer (c->t);
3448 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
3449 buffer = GCC_get_buffer (c, fwd);
3451 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
3452 if (0 == buffer && GNUNET_NO == force)
3454 GCC_check_connections ();
3458 /* Send available buffer space */
3459 if (GNUNET_YES == GCC_is_origin (c, fwd))
3461 GNUNET_assert (NULL != c->t);
3462 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
3463 GCT_unchoke_channels (c->t);
3467 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
3468 send_ack (c, buffer, fwd, force);
3470 GCC_check_connections ();
3475 * Send a message to all peers in this connection that the connection
3476 * is no longer valid.
3478 * If some peer should not receive the message, it should be zero'ed out
3479 * before calling this function.
3481 * @param c The connection whose peers to notify.
3484 GCC_send_destroy (struct CadetConnection *c)
3486 struct GNUNET_CADET_ConnectionDestroy msg;
3488 if (GNUNET_YES == c->destroy)
3490 GCC_check_connections ();
3491 msg.header.size = htons (sizeof (msg));
3492 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
3494 msg.reserved = htonl (0);
3495 LOG (GNUNET_ERROR_TYPE_DEBUG,
3496 " sending connection destroy for connection %s\n",
3499 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3500 (void) GCC_send_prebuilt_message (&msg.header, UINT16_MAX, 0, c,
3501 GNUNET_YES, GNUNET_YES, NULL, NULL);
3502 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3503 (void) GCC_send_prebuilt_message (&msg.header, UINT16_MAX, 0, c,
3504 GNUNET_NO, GNUNET_YES, NULL, NULL);
3506 GCC_check_connections ();
3511 * @brief Start a polling timer for the connection.
3513 * When a neighbor does not accept more traffic on the connection it could be
3514 * caused by a simple congestion or by a lost ACK. Polling enables to check
3515 * for the lastest ACK status for a connection.
3517 * @param c Connection.
3518 * @param fwd Should we poll in the FWD direction?
3521 GCC_start_poll (struct CadetConnection *c, int fwd)
3523 struct CadetFlowControl *fc;
3525 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3526 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL %s requested\n",
3528 if (NULL != fc->poll_task || NULL != fc->poll_msg)
3530 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL already in progress (t: %p, m: %p)\n",
3531 fc->poll_task, fc->poll_msg);
3534 if (0 == fc->queue_max)
3536 /* Should not be needed, traffic should've been cancelled. */
3538 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL not possible, peer disconnected\n");
3541 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL started on request\n");
3542 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
3543 &send_connection_poll,
3549 * @brief Stop polling a connection for ACKs.
3551 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3553 * @param c Connection.
3554 * @param fwd Should we stop the poll in the FWD direction?
3557 GCC_stop_poll (struct CadetConnection *c, int fwd)
3559 struct CadetFlowControl *fc;
3561 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3562 if (NULL != fc->poll_task)
3564 GNUNET_SCHEDULER_cancel (fc->poll_task);
3565 fc->poll_task = NULL;
3567 if (NULL != fc->poll_msg)
3569 GCC_cancel (fc->poll_msg);
3570 fc->poll_msg = NULL;
3576 * Get a (static) string for a connection.
3578 * @param c Connection.
3581 GCC_2s (const struct CadetConnection *c)
3588 static char buf[128];
3590 SPRINTF (buf, "%s (->%s)",
3591 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3594 return GNUNET_h2s (GC_h2hc (&c->id));
3599 * Log all possible info about the connection state.
3601 * @param c Connection to debug.
3602 * @param level Debug level to use.
3605 GCC_debug (const struct CadetConnection *c, enum GNUNET_ErrorType level)
3610 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
3612 __FILE__, __FUNCTION__, __LINE__);
3618 LOG2 (level, "CCC DEBUG NULL CONNECTION\n");
3622 LOG2 (level, "CCC DEBUG CONNECTION %s\n", GCC_2s (c));
3623 s = path_2s (c->path);
3624 LOG2 (level, "CCC path %s, own pos: %u\n", s, c->own_pos);
3626 LOG2 (level, "CCC state: %s, destroy: %u\n",
3627 GCC_state2s (c->state), c->destroy);
3628 LOG2 (level, "CCC pending messages: %u\n", c->pending_messages);
3629 if (NULL != c->perf)
3630 LOG2 (level, "CCC us/byte: %f\n", c->perf->avg);
3632 LOG2 (level, "CCC FWD flow control:\n");
3633 LOG2 (level, "CCC queue: %u/%u\n", c->fwd_fc.queue_n, c->fwd_fc.queue_max);
3634 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3635 c->fwd_fc.last_pid_sent, c->fwd_fc.last_pid_recv);
3636 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3637 c->fwd_fc.last_ack_sent, c->fwd_fc.last_ack_recv);
3638 LOG2 (level, "CCC recv PID bitmap: %X\n", c->fwd_fc.recv_bitmap);
3639 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3640 c->fwd_fc.poll_task, c->fwd_fc.poll_msg, c->fwd_fc.ack_msg);
3642 LOG2 (level, "CCC BCK flow control:\n");
3643 LOG2 (level, "CCC queue: %u/%u\n", c->bck_fc.queue_n, c->bck_fc.queue_max);
3644 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3645 c->bck_fc.last_pid_sent, c->bck_fc.last_pid_recv);
3646 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3647 c->bck_fc.last_ack_sent, c->bck_fc.last_ack_recv);
3648 LOG2 (level, "CCC recv PID bitmap: %X\n", c->bck_fc.recv_bitmap);
3649 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3650 c->bck_fc.poll_task, c->bck_fc.poll_msg, c->bck_fc.ack_msg);
3652 LOG2 (level, "CCC DEBUG CONNECTION END\n");