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21 * @file cadet/gnunet-service-cadet_connection.c
22 * @brief GNUnet CADET service connection handling
23 * @author Bartlomiej Polot
26 #include "gnunet_util_lib.h"
27 #include "gnunet_statistics_service.h"
28 #include "cadet_path.h"
29 #include "cadet_protocol.h"
31 #include "gnunet-service-cadet_connection.h"
32 #include "gnunet-service-cadet_peer.h"
33 #include "gnunet-service-cadet_tunnel.h"
37 * Should we run somewhat expensive checks on our invariants?
39 #define CHECK_INVARIANTS 0
42 #define LOG(level, ...) GNUNET_log_from (level,"cadet-con",__VA_ARGS__)
43 #define LOG2(level, ...) GNUNET_log_from_nocheck(level,"cadet-con",__VA_ARGS__)
46 #define CADET_MAX_POLL_TIME GNUNET_TIME_relative_multiply (\
47 GNUNET_TIME_UNIT_MINUTES,\
52 /******************************************************************************/
53 /******************************** STRUCTS **********************************/
54 /******************************************************************************/
57 * Struct to encapsulate all the Flow Control information to a peer to which
58 * we are directly connected (on a core level).
60 struct CadetFlowControl
63 * Connection this controls.
65 struct CadetConnection *c;
68 * How many messages are in the queue on this connection.
73 * How many messages do we accept in the queue.
74 * If 0, the connection is broken in this direction (next hop disconnected).
76 unsigned int queue_max;
79 * ID of the last packet sent towards the peer.
81 uint32_t last_pid_sent;
84 * ID of the last packet received from the peer.
86 uint32_t last_pid_recv;
89 * Bitmap of past 32 messages received:
90 * - LSB being @c last_pid_recv.
91 * - MSB being @c last_pid_recv - 31 (mod UINTMAX).
96 * Last ACK sent to the peer (peer can't send more than this PID).
98 uint32_t last_ack_sent;
101 * Last ACK sent towards the origin (for traffic towards leaf node).
103 uint32_t last_ack_recv;
106 * Task to poll the peer in case of a lost ACK causes stall.
108 struct GNUNET_SCHEDULER_Task *poll_task;
111 * How frequently to poll for ACKs.
113 struct GNUNET_TIME_Relative poll_time;
116 * Queued poll message, to cancel if not necessary anymore (got ACK).
118 struct CadetConnectionQueue *poll_msg;
121 * Queued poll message, to cancel if not necessary anymore (got ACK).
123 struct CadetConnectionQueue *ack_msg;
127 * Keep a record of the last messages sent on this connection.
129 struct CadetConnectionPerformance
132 * Circular buffer for storing measurements.
134 double usecsperbyte[AVG_MSGS];
137 * Running average of @c usecsperbyte.
142 * How many values of @c usecsperbyte are valid.
147 * Index of the next "free" position in @c usecsperbyte.
154 * Struct containing all information regarding a connection to a peer.
156 struct CadetConnection
159 * Tunnel this connection is part of.
161 struct CadetTunnel *t;
164 * Flow control information for traffic fwd.
166 struct CadetFlowControl fwd_fc;
169 * Flow control information for traffic bck.
171 struct CadetFlowControl bck_fc;
174 * Measure connection performance on the endpoint.
176 struct CadetConnectionPerformance *perf;
179 * ID of the connection.
181 struct GNUNET_CADET_Hash id;
184 * Path being used for the tunnel. At the origin of the connection
185 * it's a pointer to the destination's path pool, otherwise just a copy.
187 struct CadetPeerPath *path;
190 * Task to keep the used paths alive at the owner,
191 * time tunnel out on all the other peers.
193 struct GNUNET_SCHEDULER_Task *fwd_maintenance_task;
196 * Task to keep the used paths alive at the destination,
197 * time tunnel out on all the other peers.
199 struct GNUNET_SCHEDULER_Task *bck_maintenance_task;
202 * Queue handle for maintainance traffic. One handle for FWD and BCK since
203 * one peer never needs to maintain both directions (no loopback connections).
205 struct CadetPeerQueue *maintenance_q;
208 * Should equal #get_next_hop(), or NULL if that peer disconnected.
210 struct CadetPeer *next_peer;
213 * Should equal #get_prev_hop(), or NULL if that peer disconnected.
215 struct CadetPeer *prev_peer;
218 * State of the connection.
220 enum CadetConnectionState state;
223 * Position of the local peer in the path.
225 unsigned int own_pos;
228 * Pending message count.
230 unsigned int pending_messages;
234 * - if 0, connection in use.
235 * - if 1, destroy on last message.
236 * - if 2, connection is being destroyed don't re-enter.
241 * In-connection-map flag. Sometimes, when @e destroy is set but
242 * actual destruction is delayed to enable us to finish processing
243 * queues (i.e. in the direction that is still working), we remove
244 * the connection from the map to prevent it from still being
245 * found (and used) by accident. This flag is set to #GNUNET_YES
246 * for a connection that is not in the #connections map. Should
247 * only be #GNUNET_YES if #destroy is also non-zero.
252 * Counter to do exponential backoff when creating a connection (max 64).
254 unsigned short create_retry;
257 * Task to check if connection has duplicates.
259 struct GNUNET_SCHEDULER_Task *check_duplicates_task;
264 * Handle for messages queued but not yet sent.
266 struct CadetConnectionQueue
269 * Peer queue handle, to cancel if necessary.
271 struct CadetPeerQueue *q;
274 * Continuation to call once sent.
279 * Closure for @e cont.
284 * Was this a forced message? (Do not account for it)
289 /******************************************************************************/
290 /******************************* GLOBALS ***********************************/
291 /******************************************************************************/
294 * Global handle to the statistics service.
296 extern struct GNUNET_STATISTICS_Handle *stats;
299 * Local peer own ID (memory efficient handle).
301 extern GNUNET_PEER_Id myid;
304 * Local peer own ID (full value).
306 extern struct GNUNET_PeerIdentity my_full_id;
309 * Connections known, indexed by cid (CadetConnection).
311 static struct GNUNET_CONTAINER_MultiHashMap *connections;
314 * How many connections are we willing to maintain.
315 * Local connections are always allowed, even if there are more connections than max.
317 static unsigned long long max_connections;
320 * How many messages *in total* are we willing to queue, divide by number of
321 * connections to get connection queue size.
323 static unsigned long long max_msgs_queue;
326 * How often to send path keepalives. Paths timeout after 4 missed.
328 static struct GNUNET_TIME_Relative refresh_connection_time;
331 * How often to send path create / ACKs.
333 static struct GNUNET_TIME_Relative create_connection_time;
336 /******************************************************************************/
337 /******************************** STATIC ***********************************/
338 /******************************************************************************/
342 #if 0 // avoid compiler warning for unused static function
344 fc_debug (struct CadetFlowControl *fc)
346 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
347 fc->last_pid_recv, fc->last_ack_sent);
348 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
349 fc->last_pid_sent, fc->last_ack_recv);
350 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
351 fc->queue_n, fc->queue_max);
355 connection_debug (struct CadetConnection *c)
359 LOG (GNUNET_ERROR_TYPE_INFO, "DEBUG NULL CONNECTION\n");
362 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
363 peer2s (c->t->peer), GCC_2s (c));
364 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
365 c->state, c->pending_messages);
366 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
367 fc_debug (&c->fwd_fc);
368 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
369 fc_debug (&c->bck_fc);
375 * Schedule next keepalive task, taking in consideration
376 * the connection state and number of retries.
378 * @param c Connection for which to schedule the next keepalive.
379 * @param fwd Direction for the next keepalive.
382 schedule_next_keepalive (struct CadetConnection *c, int fwd);
386 * Resets the connection timeout task, some other message has done the
388 * - For the first peer on the direction this means to send
389 * a keepalive or a path confirmation message (either create or ACK).
390 * - For all other peers, this means to destroy the connection,
391 * due to lack of activity.
392 * Starts the timeout if no timeout was running (connection just created).
394 * @param c Connection whose timeout to reset.
395 * @param fwd Is this forward?
398 connection_reset_timeout (struct CadetConnection *c, int fwd);
402 * Get string description for tunnel state. Reentrant.
404 * @param s Tunnel state.
406 * @return String representation.
409 GCC_state2s (enum CadetConnectionState s)
413 case CADET_CONNECTION_NEW:
414 return "CADET_CONNECTION_NEW";
415 case CADET_CONNECTION_SENT:
416 return "CADET_CONNECTION_SENT";
417 case CADET_CONNECTION_ACK:
418 return "CADET_CONNECTION_ACK";
419 case CADET_CONNECTION_READY:
420 return "CADET_CONNECTION_READY";
421 case CADET_CONNECTION_DESTROYED:
422 return "CADET_CONNECTION_DESTROYED";
423 case CADET_CONNECTION_BROKEN:
424 return "CADET_CONNECTION_BROKEN";
427 LOG (GNUNET_ERROR_TYPE_ERROR, " conn state %u unknown!\n", s);
428 return "CADET_CONNECTION_STATE_ERROR";
434 * Initialize a Flow Control structure to the initial state.
436 * @param fc Flow Control structure to initialize.
439 fc_init (struct CadetFlowControl *fc)
441 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
442 fc->last_pid_recv = (uint32_t) -1;
443 fc->last_ack_sent = (uint32_t) 0;
444 fc->last_ack_recv = (uint32_t) 0;
445 fc->poll_task = NULL;
446 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
448 fc->queue_max = (max_msgs_queue / max_connections) + 1;
455 * @param cid Connection ID.
457 * @return conntection with the given ID @cid or NULL if not found.
459 static struct CadetConnection *
460 connection_get (const struct GNUNET_CADET_Hash *cid)
462 return GNUNET_CONTAINER_multihashmap_get (connections, GC_h2hc (cid));
467 * Mark a connection as "destroyed", to send all pending traffic and freeing
468 * all associated resources, without accepting new status changes on it.
470 * @param c Connection to mark as destroyed.
473 mark_destroyed (struct CadetConnection *c)
475 c->destroy = GNUNET_YES;
476 connection_change_state (c, CADET_CONNECTION_DESTROYED);
481 * Change the connection state. Cannot change a connection marked as destroyed.
483 * @param c Connection to change.
484 * @param state New state to set.
487 connection_change_state (struct CadetConnection* c,
488 enum CadetConnectionState state)
490 LOG (GNUNET_ERROR_TYPE_DEBUG,
491 "Connection %s state %s -> %s\n",
492 GCC_2s (c), GCC_state2s (c->state), GCC_state2s (state));
493 if (CADET_CONNECTION_DESTROYED <= c->state) /* Destroyed or broken. */
495 LOG (GNUNET_ERROR_TYPE_DEBUG, "state not changing anymore\n");
499 if (CADET_CONNECTION_READY == state)
505 * Callback called when a queued ACK message is sent.
507 * @param cls Closure (FC).
508 * @param c Connection this message was on.
509 * @param q Queue handler this call invalidates.
510 * @param type Type of message sent.
511 * @param fwd Was this a FWD going message?
512 * @param size Size of the message.
516 struct CadetConnection *c,
517 struct CadetConnectionQueue *q,
518 uint16_t type, int fwd, size_t size)
520 struct CadetFlowControl *fc = cls;
527 * Send an ACK on the connection, informing the predecessor about
528 * the available buffer space. Should not be called in case the peer
529 * is origin (no predecessor) in the @c fwd direction.
531 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
532 * the ACK itself goes "back" (dest->root).
534 * @param c Connection on which to send the ACK.
535 * @param buffer How much space free to advertise?
536 * @param fwd Is this FWD ACK? (Going dest -> root)
537 * @param force Don't optimize out.
540 send_ack (struct CadetConnection *c, unsigned int buffer, int fwd, int force)
542 struct CadetFlowControl *next_fc;
543 struct CadetFlowControl *prev_fc;
544 struct GNUNET_CADET_ACK msg;
548 /* If origin, there is no connection to send ACKs. Wrong function! */
549 GCC_check_connections ();
550 if (GCC_is_origin (c, fwd))
552 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection %s is origin in %s\n",
553 GCC_2s (c), GC_f2s (fwd));
558 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
559 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
561 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection send %s ack on %s\n",
562 GC_f2s (fwd), GCC_2s (c));
564 /* Check if we need to transmit the ACK. */
565 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
566 if (3 < delta && buffer < delta && GNUNET_NO == force)
568 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
569 LOG (GNUNET_ERROR_TYPE_DEBUG,
570 " last pid recv: %u, last ack sent: %u\n",
571 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
572 GCC_check_connections ();
576 /* Ok, ACK might be necessary, what PID to ACK? */
577 ack = prev_fc->last_pid_recv + buffer;
578 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
579 LOG (GNUNET_ERROR_TYPE_DEBUG,
580 " last pid %u, last ack %u, qmax %u, q %u\n",
581 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
582 next_fc->queue_max, next_fc->queue_n);
583 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
585 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
586 GCC_check_connections ();
590 /* Check if message is already in queue */
591 if (NULL != prev_fc->ack_msg)
593 if (GC_is_pid_bigger (ack, prev_fc->last_ack_sent))
595 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
596 GCC_cancel (prev_fc->ack_msg);
597 /* GCC_cancel triggers ack_sent(), which clears fc->ack_msg */
601 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
602 GCC_check_connections ();
607 prev_fc->last_ack_sent = ack;
609 /* Build ACK message and send on conn */
610 msg.header.size = htons (sizeof (msg));
611 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_ACK);
612 msg.ack = htonl (ack);
615 prev_fc->ack_msg = GCC_send_prebuilt_message (&msg.header, UINT16_MAX, ack,
618 GNUNET_assert (NULL != prev_fc->ack_msg);
619 GCC_check_connections ();
624 * Callback called when a connection queued message is sent.
626 * Calculates the average time and connection packet tracking.
628 * @param cls Closure (ConnectionQueue Handle).
629 * @param c Connection this message was on.
630 * @param sent Was it really sent? (Could have been canceled)
631 * @param type Type of message sent.
632 * @param pid Packet ID, or 0 if not applicable (create, destroy, etc).
633 * @param fwd Was this a FWD going message?
634 * @param size Size of the message.
635 * @param wait Time spent waiting for core (only the time for THIS message)
636 * @return #GNUNET_YES if connection was destroyed, #GNUNET_NO otherwise.
639 conn_message_sent (void *cls,
640 struct CadetConnection *c, int sent,
641 uint16_t type, uint32_t pid, int fwd, size_t size,
642 struct GNUNET_TIME_Relative wait)
644 struct CadetConnectionPerformance *p;
645 struct CadetFlowControl *fc;
646 struct CadetConnectionQueue *q = cls;
650 GCC_check_connections ();
651 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection message_sent\n");
653 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
655 fc = fwd ? &c->fwd_fc : &c->bck_fc;
656 LOG (GNUNET_ERROR_TYPE_DEBUG, " %ssent %s %s pid %u\n",
657 sent ? "" : "not ", GC_f2s (fwd), GC_m2s (type), pid);
663 LOG (GNUNET_ERROR_TYPE_DEBUG, " calling cont\n");
664 q->cont (q->cont_cls, c, q, type, fwd, size);
668 else if (type == GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED
669 || type == GNUNET_MESSAGE_TYPE_CADET_AX)
671 /* If NULL == q and ENCRYPTED == type, message must have been ch_mngmnt */
680 if (type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN
681 && type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY)
683 LOG (GNUNET_ERROR_TYPE_ERROR, "Message %s sent on NULL connection!\n",
686 GCC_check_connections ();
689 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P- %p %u\n", c, c->pending_messages);
690 c->pending_messages--;
691 if ( (GNUNET_YES == c->destroy) &&
692 (0 == c->pending_messages) )
694 LOG (GNUNET_ERROR_TYPE_DEBUG,
695 "! destroying connection!\n");
697 GCC_check_connections ();
700 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
703 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
704 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
705 c->maintenance_q = NULL;
706 /* Don't trigger a keepalive for sent ACKs, only SYN and SYNACKs */
707 if (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE == type || !fwd)
708 schedule_next_keepalive (c, fwd);
711 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
712 case GNUNET_MESSAGE_TYPE_CADET_AX:
713 if (GNUNET_YES == sent)
715 GNUNET_assert (NULL != q);
716 fc->last_pid_sent = pid;
717 if (GC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
718 GCC_start_poll (c, fwd);
719 GCC_send_ack (c, fwd, GNUNET_NO);
720 connection_reset_timeout (c, fwd);
723 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
724 if (GNUNET_NO == forced)
727 LOG (GNUNET_ERROR_TYPE_DEBUG,
728 "! accounting pid %u\n",
733 LOG (GNUNET_ERROR_TYPE_DEBUG,
734 "! forced, Q_N not accounting pid %u\n",
739 case GNUNET_MESSAGE_TYPE_CADET_KX:
740 if (GNUNET_YES == sent)
741 connection_reset_timeout (c, fwd);
744 case GNUNET_MESSAGE_TYPE_CADET_POLL:
748 case GNUNET_MESSAGE_TYPE_CADET_ACK:
752 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
753 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
757 LOG (GNUNET_ERROR_TYPE_ERROR, "%s unknown\n", GC_m2s (type));
761 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
764 return GNUNET_NO; /* Only endpoints are interested in timing. */
767 usecsperbyte = ((double) wait.rel_value_us) / size;
768 if (p->size == AVG_MSGS)
770 /* Array is full. Substract oldest value, add new one and store. */
771 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
772 p->usecsperbyte[p->idx] = usecsperbyte;
773 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
777 /* Array not yet full. Add current value to avg and store. */
778 p->usecsperbyte[p->idx] = usecsperbyte;
780 p->avg += p->usecsperbyte[p->idx];
784 p->idx = (p->idx + 1) % AVG_MSGS;
785 GCC_check_connections ();
791 * Get the previous hop in a connection
793 * @param c Connection.
795 * @return Previous peer in the connection.
797 static struct CadetPeer *
798 get_prev_hop (const struct CadetConnection *c)
804 LOG (GNUNET_ERROR_TYPE_DEBUG,
805 " get prev hop %s [%u/%u]\n",
806 GCC_2s (c), c->own_pos, c->path->length);
807 if (0 == c->own_pos || c->path->length < 2)
808 id = c->path->peers[0];
810 id = c->path->peers[c->own_pos - 1];
812 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
813 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
815 return GCP_get_short (id, GNUNET_YES);
820 * Get the next hop in a connection
822 * @param c Connection.
824 * @return Next peer in the connection.
826 static struct CadetPeer *
827 get_next_hop (const struct CadetConnection *c)
834 LOG (GNUNET_ERROR_TYPE_DEBUG, " get next hop %s [%u/%u]\n",
835 GCC_2s (c), c->own_pos, c->path->length);
836 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
837 id = c->path->peers[c->path->length - 1];
839 id = c->path->peers[c->own_pos + 1];
841 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
842 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
844 return GCP_get_short (id, GNUNET_YES);
849 * Check that the direct neighbours (previous and next hop)
850 * are properly associated with this connection.
852 * @param c connection to check
855 check_neighbours (const struct CadetConnection *c)
858 return; /* nothing to check */
859 GCP_check_connection (get_next_hop (c), c);
860 GCP_check_connection (get_prev_hop (c), c);
865 * Helper for #GCC_check_connections(). Calls #check_neighbours().
869 * @param value the `struct CadetConnection` to check
870 * @return #GNUNET_OK (continue to iterate)
873 check_connection (void *cls,
874 const struct GNUNET_HashCode *key,
877 struct CadetConnection *c = value;
879 check_neighbours (c);
885 * Check invariants for all connections using #check_neighbours().
888 GCC_check_connections ()
890 if (0 == CHECK_INVARIANTS)
892 if (NULL == connections)
894 GNUNET_CONTAINER_multihashmap_iterate (connections,
901 * Get the hop in a connection.
903 * @param c Connection.
904 * @param fwd Next in the FWD direction?
906 * @return Next peer in the connection.
908 static struct CadetPeer *
909 get_hop (struct CadetConnection *c, int fwd)
911 return (fwd) ? get_next_hop (c) : get_prev_hop (c);
916 * Get a bit mask for a message received out-of-order.
918 * @param last_pid_recv Last PID we received prior to the out-of-order.
919 * @param ooo_pid PID of the out-of-order message.
922 get_recv_bitmask (uint32_t last_pid_recv, uint32_t ooo_pid)
924 return 1 << (last_pid_recv - ooo_pid);
929 * Check is an out-of-order message is ok:
930 * - at most 31 messages behind.
933 * @param last_pid_recv Last in-order PID received.
936 is_ooo_ok (uint32_t last_pid_recv, uint32_t ooo_pid, uint32_t ooo_bitmap)
940 if (GC_is_pid_bigger (last_pid_recv - 31, ooo_pid))
943 mask = get_recv_bitmask (last_pid_recv, ooo_pid);
944 if (0 != (ooo_bitmap & mask))
952 * Is traffic coming from this sender 'FWD' traffic?
954 * @param c Connection to check.
955 * @param sender Peer identity of neighbor.
957 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
958 * the traffic is 'FWD'.
959 * #GNUNET_NO for BCK.
960 * #GNUNET_SYSERR for errors.
963 is_fwd (const struct CadetConnection *c,
964 const struct GNUNET_PeerIdentity *sender)
968 id = GNUNET_PEER_search (sender);
969 if (GCP_get_short_id (get_prev_hop (c)) == id)
972 if (GCP_get_short_id (get_next_hop (c)) == id)
976 return GNUNET_SYSERR;
981 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
982 * or a first CONNECTION_ACK directed to us.
984 * @param connection Connection to confirm.
985 * @param fwd Should we send it FWD? (root->dest)
986 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
989 send_connection_ack (struct CadetConnection *connection, int fwd)
991 struct CadetTunnel *t;
992 size_t size = sizeof (struct GNUNET_CADET_ConnectionACK);
994 GCC_check_connections ();
996 LOG (GNUNET_ERROR_TYPE_INFO,
997 "==> { C %s ACK} %19s on conn %s (%p) %s [%5u]\n",
998 GC_f2s (!fwd), "", GCC_2s (connection), connection, GC_f2s (fwd), size);
999 GCP_queue_add (get_hop (connection, fwd), NULL,
1000 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK, UINT16_MAX, 0,
1001 size, connection, fwd, &conn_message_sent, NULL);
1002 connection->pending_messages++;
1003 if (CADET_TUNNEL_NEW == GCT_get_cstate (t))
1004 GCT_change_cstate (t, CADET_TUNNEL_WAITING);
1005 if (CADET_CONNECTION_READY != connection->state)
1006 connection_change_state (connection, CADET_CONNECTION_SENT);
1007 GCC_check_connections ();
1012 * Send a notification that a connection is broken.
1014 * @param c Connection that is broken.
1015 * @param id1 Peer that has disconnected.
1016 * @param id2 Peer that has disconnected.
1017 * @param fwd Direction towards which to send it.
1020 send_broken (struct CadetConnection *c,
1021 const struct GNUNET_PeerIdentity *id1,
1022 const struct GNUNET_PeerIdentity *id2,
1025 struct GNUNET_CADET_ConnectionBroken msg;
1027 GCC_check_connections ();
1028 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1029 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1033 GNUNET_assert (NULL ==
1034 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, 0, c, fwd,
1035 GNUNET_YES, NULL, NULL));
1036 GCC_check_connections ();
1041 * Send a notification that a connection is broken, when a connection
1042 * isn't even known to the local peer or soon to be destroyed.
1044 * @param connection_id Connection ID.
1045 * @param id1 Peer that has disconnected, probably local peer.
1046 * @param id2 Peer that has disconnected can be NULL if unknown.
1047 * @param peer Peer to notify (neighbor who sent the connection).
1050 send_broken_unknown (const struct GNUNET_CADET_Hash *connection_id,
1051 const struct GNUNET_PeerIdentity *id1,
1052 const struct GNUNET_PeerIdentity *id2,
1053 const struct GNUNET_PeerIdentity *peer_id)
1055 struct GNUNET_CADET_ConnectionBroken *msg;
1056 struct CadetPeer *neighbor;
1058 GCC_check_connections ();
1059 LOG (GNUNET_ERROR_TYPE_INFO, "--> BROKEN on unknown connection %s\n",
1060 GNUNET_h2s (GC_h2hc (connection_id)));
1062 msg = GNUNET_new (struct GNUNET_CADET_ConnectionBroken);
1063 msg->header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1064 msg->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1065 msg->cid = *connection_id;
1070 memset (&msg->peer2, 0, sizeof (msg->peer2));
1071 neighbor = GCP_get (peer_id, GNUNET_NO); /* We MUST know neighbor. */
1072 GNUNET_assert (NULL != neighbor);
1073 GCP_queue_add (neighbor, msg, GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN,
1074 UINT16_MAX, 2, sizeof (struct GNUNET_CADET_ConnectionBroken),
1075 NULL, GNUNET_SYSERR, /* connection, fwd */
1076 NULL, NULL); /* continuation */
1077 GCC_check_connections ();
1082 * Send keepalive packets for a connection.
1084 * @param c Connection to keep alive..
1085 * @param fwd Is this a FWD keepalive? (owner -> dest).
1088 send_connection_keepalive (struct CadetConnection *c, int fwd)
1090 struct GNUNET_MessageHeader msg;
1091 struct CadetFlowControl *fc;
1093 GCC_check_connections ();
1094 LOG (GNUNET_ERROR_TYPE_INFO,
1095 "keepalive %s for connection %s\n",
1096 GC_f2s (fwd), GCC_2s (c));
1098 GNUNET_assert (NULL != c->t);
1099 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1100 if (0 < fc->queue_n || GNUNET_YES == GCT_has_queued_traffic (c->t))
1102 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, traffic in queue\n");
1106 GNUNET_STATISTICS_update (stats, "# keepalives sent", 1, GNUNET_NO);
1108 GNUNET_assert (NULL != c->t);
1109 msg.size = htons (sizeof (msg));
1110 msg.type = htons (GNUNET_MESSAGE_TYPE_CADET_KEEPALIVE);
1112 GNUNET_assert (NULL ==
1113 GCT_send_prebuilt_message (&msg, c->t, c,
1114 GNUNET_NO, NULL, NULL));
1115 GCC_check_connections ();
1120 * Send CONNECTION_{CREATE/ACK} packets for a connection.
1122 * @param c Connection for which to send the message.
1123 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
1126 connection_recreate (struct CadetConnection *c, int fwd)
1128 LOG (GNUNET_ERROR_TYPE_DEBUG,
1129 "sending connection recreate\n");
1131 GCC_send_create (c);
1133 send_connection_ack (c, GNUNET_NO);
1138 * Generic connection timer management.
1139 * Depending on the role of the peer in the connection will send the
1140 * appropriate message (build or keepalive)
1142 * @param c Conncetion to maintain.
1143 * @param fwd Is FWD?
1146 connection_maintain (struct CadetConnection *c, int fwd)
1148 if (GNUNET_NO != c->destroy)
1150 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, being destroyed\n");
1157 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1161 if (CADET_TUNNEL_SEARCHING == GCT_get_cstate (c->t))
1163 /* If status is SEARCHING, why is there a connection? Should be WAITING */
1165 GCT_debug (c->t, GNUNET_ERROR_TYPE_ERROR);
1166 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, tunnel SEARCHING\n");
1167 schedule_next_keepalive (c, fwd);
1172 case CADET_CONNECTION_NEW:
1175 case CADET_CONNECTION_SENT:
1176 connection_recreate (c, fwd);
1178 case CADET_CONNECTION_READY:
1179 send_connection_keepalive (c, fwd);
1188 * Keep the connection alive.
1190 * @param c Connection to keep alive.
1191 * @param fwd Direction.
1192 * @param shutdown Are we shutting down? (Don't send traffic)
1193 * Non-zero value for true, not necessarily GNUNET_YES.
1196 connection_keepalive (struct CadetConnection *c, int fwd, int shutdown)
1198 GCC_check_connections ();
1199 LOG (GNUNET_ERROR_TYPE_DEBUG,
1200 "%s keepalive for %s\n",
1201 GC_f2s (fwd), GCC_2s (c));
1204 c->fwd_maintenance_task = NULL;
1206 c->bck_maintenance_task = NULL;
1208 if (GNUNET_NO != shutdown)
1211 connection_maintain (c, fwd);
1212 GCC_check_connections ();
1213 /* Next execution will be scheduled by message_sent or _maintain*/
1218 * Keep the connection alive in the FWD direction.
1220 * @param cls Closure (connection to keepalive).
1221 * @param tc TaskContext.
1224 connection_fwd_keepalive (void *cls,
1225 const struct GNUNET_SCHEDULER_TaskContext *tc)
1227 GCC_check_connections ();
1228 connection_keepalive ((struct CadetConnection *) cls,
1230 tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN);
1231 GCC_check_connections ();
1236 * Keep the connection alive in the BCK direction.
1238 * @param cls Closure (connection to keepalive).
1239 * @param tc TaskContext.
1242 connection_bck_keepalive (void *cls,
1243 const struct GNUNET_SCHEDULER_TaskContext *tc)
1245 GCC_check_connections ();
1246 connection_keepalive ((struct CadetConnection *) cls,
1248 tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN);
1249 GCC_check_connections ();
1254 * Schedule next keepalive task, taking in consideration
1255 * the connection state and number of retries.
1257 * If the peer is not the origin, do nothing.
1259 * @param c Connection for which to schedule the next keepalive.
1260 * @param fwd Direction for the next keepalive.
1263 schedule_next_keepalive (struct CadetConnection *c, int fwd)
1265 struct GNUNET_TIME_Relative delay;
1266 struct GNUNET_SCHEDULER_Task * *task_id;
1267 GNUNET_SCHEDULER_TaskCallback keepalive_task;
1269 GCC_check_connections ();
1270 if (GNUNET_NO == GCC_is_origin (c, fwd))
1273 /* Calculate delay to use, depending on the state of the connection */
1274 if (CADET_CONNECTION_READY == c->state)
1276 delay = refresh_connection_time;
1280 if (1 > c->create_retry)
1281 c->create_retry = 1;
1282 delay = GNUNET_TIME_relative_multiply (create_connection_time,
1284 if (c->create_retry < 64)
1285 c->create_retry *= 2;
1288 /* Select direction-dependent parameters */
1289 if (GNUNET_YES == fwd)
1291 task_id = &c->fwd_maintenance_task;
1292 keepalive_task = &connection_fwd_keepalive;
1296 task_id = &c->bck_maintenance_task;
1297 keepalive_task = &connection_bck_keepalive;
1300 /* Check that no one scheduled it before us */
1301 if (NULL != *task_id)
1303 /* No need for a _break. It can happen for instance when sending a SYNACK
1304 * for a duplicate SYN: the first SYNACK scheduled the task. */
1305 GNUNET_SCHEDULER_cancel (*task_id);
1308 /* Schedule the task */
1309 *task_id = GNUNET_SCHEDULER_add_delayed (delay,
1312 LOG (GNUNET_ERROR_TYPE_DEBUG,
1313 "next keepalive in %s\n",
1314 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1315 GCC_check_connections ();
1320 * @brief Re-initiate traffic on this connection if necessary.
1322 * Check if there is traffic queued towards this peer
1323 * and the core transmit handle is NULL (traffic was stalled).
1324 * If so, call core tmt rdy.
1326 * @param c Connection on which initiate traffic.
1327 * @param fwd Is this about fwd traffic?
1330 connection_unlock_queue (struct CadetConnection *c, int fwd)
1332 struct CadetPeer *peer;
1334 GCC_check_connections ();
1335 LOG (GNUNET_ERROR_TYPE_DEBUG,
1336 "connection_unlock_queue %s on %s\n",
1337 GC_f2s (fwd), GCC_2s (c));
1339 if (GCC_is_terminal (c, fwd))
1341 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal, can unlock!\n");
1345 peer = get_hop (c, fwd);
1346 GCP_queue_unlock (peer, c);
1347 GCC_check_connections ();
1352 * Cancel all transmissions that belong to a certain connection.
1354 * If the connection is scheduled for destruction and no more messages are left,
1355 * the connection will be destroyed by the continuation call.
1357 * @param c Connection which to cancel. Might be destroyed during this call.
1358 * @param fwd Cancel fwd traffic?
1361 connection_cancel_queues (struct CadetConnection *c,
1364 struct CadetFlowControl *fc;
1365 struct CadetPeer *peer;
1367 GCC_check_connections ();
1368 LOG (GNUNET_ERROR_TYPE_DEBUG,
1369 "Cancel %s queues for connection %s\n",
1370 GC_f2s (fwd), GCC_2s (c));
1377 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1378 if (NULL != fc->poll_task)
1380 GNUNET_SCHEDULER_cancel (fc->poll_task);
1381 fc->poll_task = NULL;
1382 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL task for fc %p\n", fc);
1384 if (NULL != fc->poll_msg)
1386 GCC_cancel (fc->poll_msg);
1387 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL msg for fc %p\n", fc);
1389 peer = get_hop (c, fwd);
1390 GCP_queue_cancel (peer, c);
1391 GCC_check_connections ();
1396 * Function called if a connection has been stalled for a while,
1397 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1399 * @param cls Closure (poll ctx).
1400 * @param tc TaskContext.
1403 connection_poll (void *cls,
1404 const struct GNUNET_SCHEDULER_TaskContext *tc);
1408 * Callback called when a queued POLL message is sent.
1410 * @param cls Closure (flow control context).
1411 * @param c Connection this message was on.
1412 * @param q Queue handler this call invalidates.
1413 * @param type Type of message sent.
1414 * @param fwd Was this a FWD going message?
1415 * @param size Size of the message.
1418 poll_sent (void *cls,
1419 struct CadetConnection *c,
1420 struct CadetConnectionQueue *q,
1421 uint16_t type, int fwd, size_t size)
1423 struct CadetFlowControl *fc = cls;
1425 GNUNET_assert (fc->poll_msg == q);
1426 fc->poll_msg = NULL;
1427 if (2 == c->destroy)
1429 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL canceled on shutdown\n");
1432 if (0 == fc->queue_max)
1434 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL cancelled: neighbor disconnected\n");
1437 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL sent for %s, scheduling new one!\n",
1439 GNUNET_assert (NULL == fc->poll_task);
1440 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1441 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1444 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1449 * Function called if a connection has been stalled for a while,
1450 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1452 * @param cls Closure (poll ctx).
1453 * @param tc TaskContext.
1456 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1458 struct CadetFlowControl *fc = cls;
1459 struct GNUNET_CADET_Poll msg;
1460 struct CadetConnection *c;
1463 fc->poll_task = NULL;
1464 GCC_check_connections ();
1465 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1471 fwd = fc == &c->fwd_fc;
1472 LOG (GNUNET_ERROR_TYPE_DEBUG, "Polling connection %s %s\n",
1473 GCC_2s (c), GC_f2s (fwd));
1475 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_POLL);
1476 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 * Resend all queued messages for a connection on other connections of the
1489 * same tunnel, if possible. The connection WILL BE DESTROYED by this function.
1491 * @param c Connection whose messages to resend.
1492 * @param fwd Resend fwd messages?
1495 resend_messages_and_destroy (struct CadetConnection *c, int fwd)
1497 struct GNUNET_MessageHeader *out_msg;
1498 struct CadetTunnel *t = c->t;
1499 struct CadetPeer *neighbor;
1500 unsigned int pending;
1503 GCC_check_connections ();
1506 destroyed = GNUNET_NO;
1507 neighbor = get_hop (c, fwd);
1508 pending = c->pending_messages;
1510 while (NULL != (out_msg = GCP_connection_pop (neighbor, c, &destroyed)))
1513 GCT_resend_message (out_msg, t);
1514 GNUNET_free (out_msg);
1517 /* All pending messages should have been popped,
1518 * and the connection destroyed by the continuation.
1520 if (GNUNET_YES != destroyed)
1525 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1526 if (NULL != t) GCT_debug (t, GNUNET_ERROR_TYPE_ERROR);
1530 GCC_check_connections ();
1535 * Generic connection timeout implementation.
1537 * Timeout function due to lack of keepalive/traffic from an endpoint.
1538 * Destroys connection if called.
1540 * @param c Connection to destroy.
1541 * @param fwd Was the timeout from the origin? (FWD timeout)
1544 connection_timeout (struct CadetConnection *c, int fwd)
1546 struct CadetFlowControl *reverse_fc;
1548 GCC_check_connections ();
1549 reverse_fc = fwd ? &c->bck_fc : &c->fwd_fc;
1551 LOG (GNUNET_ERROR_TYPE_INFO,
1552 "Connection %s %s timed out. Destroying.\n",
1555 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1557 if (GCC_is_origin (c, fwd)) /* Loopback? Something is wrong! */
1563 /* If dest, salvage queued traffic. */
1564 if (GCC_is_origin (c, !fwd))
1566 const struct GNUNET_PeerIdentity *next_hop;
1568 next_hop = GCP_get_id (fwd ? get_prev_hop (c) : get_next_hop (c));
1569 send_broken_unknown (&c->id, &my_full_id, NULL, next_hop);
1570 if (0 < reverse_fc->queue_n)
1571 resend_messages_and_destroy (c, !fwd);
1572 GCC_check_connections ();
1577 GCC_check_connections ();
1582 * Timeout function due to lack of keepalive/traffic from the owner.
1583 * Destroys connection if called.
1585 * @param cls Closure (connection to destroy).
1586 * @param tc TaskContext.
1589 connection_fwd_timeout (void *cls,
1590 const struct GNUNET_SCHEDULER_TaskContext *tc)
1592 struct CadetConnection *c = cls;
1594 c->fwd_maintenance_task = NULL;
1595 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1597 GCC_check_connections ();
1598 connection_timeout (c, GNUNET_YES);
1599 GCC_check_connections ();
1604 * Timeout function due to lack of keepalive/traffic from the destination.
1605 * Destroys connection if called.
1607 * @param cls Closure (connection to destroy).
1608 * @param tc TaskContext
1611 connection_bck_timeout (void *cls,
1612 const struct GNUNET_SCHEDULER_TaskContext *tc)
1614 struct CadetConnection *c = cls;
1616 c->bck_maintenance_task = NULL;
1617 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1619 GCC_check_connections ();
1620 connection_timeout (c, GNUNET_NO);
1621 GCC_check_connections ();
1626 * Resets the connection timeout task, some other message has done the
1628 * - For the first peer on the direction this means to send
1629 * a keepalive or a path confirmation message (either create or ACK).
1630 * - For all other peers, this means to destroy the connection,
1631 * due to lack of activity.
1632 * Starts the timeout if no timeout was running (connection just created).
1634 * @param c Connection whose timeout to reset.
1635 * @param fwd Is this forward?
1637 * TODO use heap to improve efficiency of scheduler.
1640 connection_reset_timeout (struct CadetConnection *c, int fwd)
1642 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1643 if (GCC_is_origin (c, fwd)) /* Startpoint */
1645 schedule_next_keepalive (c, fwd);
1647 else /* Relay, endpoint. */
1649 struct GNUNET_TIME_Relative delay;
1650 struct GNUNET_SCHEDULER_Task * *ti;
1651 GNUNET_SCHEDULER_TaskCallback f;
1653 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1656 GNUNET_SCHEDULER_cancel (*ti);
1657 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1658 LOG (GNUNET_ERROR_TYPE_DEBUG,
1659 " timing out in %s\n",
1660 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_NO));
1661 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1662 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1668 * Iterator to compare each connection's path with the path of a new connection.
1670 * If the connection coincides, the c member of path is set to the connection
1671 * and the destroy flag of the connection is set.
1673 * @param cls Closure (new path).
1674 * @param c Connection in the tunnel to check.
1677 check_path (void *cls, struct CadetConnection *c)
1679 struct CadetConnection *new_conn = cls;
1680 struct CadetPeerPath *path = new_conn->path;
1682 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking %s (%p), length %u\n",
1683 GCC_2s (c), c, c->path->length);
1686 && GNUNET_NO == c->destroy
1687 && CADET_CONNECTION_BROKEN != c->state
1688 && CADET_CONNECTION_DESTROYED != c->state
1689 && path_equivalent (path, c->path))
1691 new_conn->destroy = GNUNET_YES; /* Do not mark_destroyed, */
1692 new_conn->path->c = c; /* this is only a flag for the Iterator. */
1693 LOG (GNUNET_ERROR_TYPE_DEBUG, " MATCH!\n");
1699 * Finds out if this path is already being used by an existing connection.
1701 * Checks the tunnel towards the destination to see if it contains
1702 * any connection with the same path.
1704 * If the existing connection is ready, it is kept.
1705 * Otherwise if the sender has a smaller ID that ours, we accept it (and
1706 * the peer will eventually reject our attempt).
1708 * @param path Path to check.
1709 * @return #GNUNET_YES if the tunnel has a connection with the same path,
1710 * #GNUNET_NO otherwise.
1713 does_connection_exist (struct CadetConnection *conn)
1715 struct CadetPeer *p;
1716 struct CadetTunnel *t;
1717 struct CadetConnection *c;
1719 p = GCP_get_short (conn->path->peers[0], GNUNET_NO);
1722 t = GCP_get_tunnel (p);
1726 LOG (GNUNET_ERROR_TYPE_DEBUG, "Checking for duplicates\n");
1728 GCT_iterate_connections (t, &check_path, conn);
1730 if (GNUNET_YES == conn->destroy)
1733 conn->destroy = GNUNET_NO;
1734 conn->path->c = conn;
1735 LOG (GNUNET_ERROR_TYPE_DEBUG, " found duplicate of %s\n", GCC_2s (conn));
1736 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate: %s\n", GCC_2s (c));
1737 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1738 if (CADET_CONNECTION_READY == c->state)
1740 /* The other peer confirmed a live connection with this path,
1741 * why is it trying to duplicate it. */
1742 GNUNET_STATISTICS_update (stats, "# duplicate connections", 1, GNUNET_NO);
1745 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate not valid, connection unique\n");
1750 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s has no duplicates\n", GCC_2s (conn));
1757 * @brief Check if the tunnel this connection belongs to has any other
1758 * connection with the same path, and destroy one if so.
1760 * @param cls Closure (connection to check).
1761 * @param tc Task context.
1764 check_duplicates (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1766 struct CadetConnection *c = cls;
1768 c->check_duplicates_task = NULL;
1769 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1772 if (GNUNET_YES == does_connection_exist (c))
1774 GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1775 send_broken (c, &my_full_id, &my_full_id, GCC_is_origin (c, GNUNET_YES));
1783 * Wait for enough time to let any dead connections time out and check for
1784 * any remaining duplicates.
1786 * @param c Connection that is a potential duplicate.
1789 schedule_check_duplicates (struct CadetConnection *c)
1791 struct GNUNET_TIME_Relative delay;
1793 if (NULL != c->check_duplicates_task)
1796 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 5);
1797 c->check_duplicates_task = GNUNET_SCHEDULER_add_delayed (delay,
1805 * Add the connection to the list of both neighbors.
1807 * @param c Connection.
1809 * @return #GNUNET_OK if everything went fine
1810 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1813 register_neighbors (struct CadetConnection *c)
1815 c->next_peer = get_next_hop (c);
1816 c->prev_peer = get_prev_hop (c);
1817 GNUNET_assert (c->next_peer != c->prev_peer);
1818 LOG (GNUNET_ERROR_TYPE_DEBUG,
1819 "register neighbors for connection %s\n",
1821 path_debug (c->path);
1822 LOG (GNUNET_ERROR_TYPE_DEBUG,
1823 "own pos %u\n", c->own_pos);
1824 LOG (GNUNET_ERROR_TYPE_DEBUG,
1825 "putting connection %s to next peer %p\n",
1828 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n",
1830 GCP_2s (c->next_peer));
1831 LOG (GNUNET_ERROR_TYPE_DEBUG,
1832 "putting connection %s to prev peer %p\n",
1835 LOG (GNUNET_ERROR_TYPE_DEBUG,
1836 "prev peer %p %s\n",
1838 GCP_2s (c->prev_peer));
1840 if ( (GNUNET_NO == GCP_is_neighbor (c->next_peer)) ||
1841 (GNUNET_NO == GCP_is_neighbor (c->prev_peer)) )
1843 if (GCC_is_origin (c, GNUNET_YES))
1844 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1845 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1847 LOG (GNUNET_ERROR_TYPE_DEBUG,
1848 " register neighbors failed\n");
1849 LOG (GNUNET_ERROR_TYPE_DEBUG,
1850 " prev: %s, neighbor?: %d\n",
1851 GCP_2s (c->prev_peer),
1852 GCP_is_neighbor (c->prev_peer));
1853 LOG (GNUNET_ERROR_TYPE_DEBUG,
1854 " next: %s, neighbor?: %d\n",
1855 GCP_2s (c->next_peer),
1856 GCP_is_neighbor (c->next_peer));
1857 return GNUNET_SYSERR;
1859 GCP_add_connection (c->next_peer, c, GNUNET_NO);
1860 GCP_add_connection (c->prev_peer, c, GNUNET_YES);
1867 * Remove the connection from the list of both neighbors.
1869 * @param c Connection.
1872 unregister_neighbors (struct CadetConnection *c)
1874 // struct CadetPeer *peer; FIXME dont use next_peer, prev_peer
1875 /* Either already unregistered or never got registered, it's ok either way. */
1876 if (NULL == c->path)
1878 if (NULL != c->next_peer)
1880 GCP_remove_connection (c->next_peer, c);
1881 c->next_peer = NULL;
1883 if (NULL != c->prev_peer)
1885 GCP_remove_connection (c->prev_peer, c);
1886 c->prev_peer = NULL;
1892 * Invalidates all paths towards all peers that comprise the connection which
1893 * rely on the disconnected peer.
1895 * ~O(n^3) (peers in connection * paths/peer * links/path)
1897 * @param c Connection whose peers' paths to clean.
1898 * @param disconnected Peer that disconnected.
1901 invalidate_paths (struct CadetConnection *c, struct CadetPeer *disconnected)
1903 struct CadetPeer *peer;
1906 for (i = 0; i < c->path->length; i++)
1908 peer = GCP_get_short (c->path->peers[i], GNUNET_NO);
1910 GCP_notify_broken_link (peer, &my_full_id, GCP_get_id (disconnected));
1916 * Bind the connection to the peer and the tunnel to that peer.
1918 * If the peer has no tunnel, create one. Update tunnel and connection
1919 * data structres to reflect new status.
1921 * @param c Connection.
1925 add_to_peer (struct CadetConnection *c,
1926 struct CadetPeer *peer)
1928 GCP_add_tunnel (peer);
1929 c->t = GCP_get_tunnel (peer);
1930 GCT_add_connection (c->t, c);
1935 * Log receipt of message on stderr (INFO level).
1937 * @param message Message received.
1938 * @param peer Peer who sent the message.
1939 * @param hash Connection ID.
1942 log_message (const struct GNUNET_MessageHeader *message,
1943 const struct GNUNET_PeerIdentity *peer,
1944 const struct GNUNET_CADET_Hash *hash)
1950 size = ntohs (message->size);
1951 type = ntohs (message->type);
1954 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
1955 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
1956 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
1957 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
1963 LOG (GNUNET_ERROR_TYPE_INFO, "<%s %s on conn %s from %s, %6u bytes\n",
1964 arrow, GC_m2s (type), GNUNET_h2s (GC_h2hc (hash)),
1965 GNUNET_i2s (peer), (unsigned int) size);
1968 /******************************************************************************/
1969 /******************************** API ***********************************/
1970 /******************************************************************************/
1973 * Core handler for connection creation.
1975 * @param cls Closure (unused).
1976 * @param peer Sender (neighbor).
1977 * @param message Message.
1978 * @return #GNUNET_OK to keep the connection open,
1979 * #GNUNET_SYSERR to close it (signal serious error)
1982 GCC_handle_create (void *cls,
1983 const struct GNUNET_PeerIdentity *peer,
1984 const struct GNUNET_MessageHeader *message)
1986 struct GNUNET_CADET_ConnectionCreate *msg;
1987 struct GNUNET_PeerIdentity *id;
1988 struct GNUNET_CADET_Hash *cid;
1989 struct CadetPeerPath *path;
1990 struct CadetPeer *dest_peer;
1991 struct CadetPeer *orig_peer;
1992 struct CadetConnection *c;
1993 unsigned int own_pos;
1996 GCC_check_connections ();
1998 size = ntohs (message->size);
1999 if (size < sizeof (struct GNUNET_CADET_ConnectionCreate))
2001 GNUNET_break_op (0);
2005 /* Calculate hops */
2006 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
2007 if (size % sizeof (struct GNUNET_PeerIdentity))
2009 GNUNET_break_op (0);
2012 if (0 != size % sizeof (struct GNUNET_PeerIdentity))
2014 GNUNET_break_op (0);
2017 size /= sizeof (struct GNUNET_PeerIdentity);
2020 GNUNET_break_op (0);
2023 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
2025 /* Get parameters */
2026 msg = (struct GNUNET_CADET_ConnectionCreate *) message;
2028 log_message (message, peer, cid);
2029 id = (struct GNUNET_PeerIdentity *) &msg[1];
2030 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
2032 /* Create connection */
2033 c = connection_get (cid);
2036 path = path_build_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
2037 size, myid, &own_pos);
2040 /* Path was malformed, probably our own ID was not in it. */
2041 GNUNET_STATISTICS_update (stats, "# malformed paths", 1, GNUNET_NO);
2042 GNUNET_break_op (0);
2048 /* We received this request from a neighbor, we cannot be origin */
2049 GNUNET_STATISTICS_update (stats, "# fake paths", 1, GNUNET_NO);
2050 GNUNET_break_op (0);
2051 path_destroy (path);
2055 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
2056 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
2057 c = GCC_new (cid, NULL, path, own_pos);
2060 if (path->length - 1 == own_pos)
2062 /* If we are destination, why did the creation fail? */
2064 path_destroy (path);
2065 GCC_check_connections ();
2068 send_broken_unknown (cid, &my_full_id,
2069 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
2071 path_destroy (path);
2072 GCC_check_connections ();
2075 GCP_add_path_to_all (path, GNUNET_NO);
2076 connection_reset_timeout (c, GNUNET_YES);
2080 path = path_duplicate (c->path);
2082 if (CADET_CONNECTION_NEW == c->state)
2083 connection_change_state (c, CADET_CONNECTION_SENT);
2085 /* Remember peers */
2086 dest_peer = GCP_get (&id[size - 1], GNUNET_YES);
2087 orig_peer = GCP_get (&id[0], GNUNET_YES);
2089 /* Is it a connection to us? */
2090 if (c->own_pos == path->length - 1)
2092 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
2093 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
2095 add_to_peer (c, orig_peer);
2096 if (GNUNET_YES == does_connection_exist (c))
2098 /* Peer created a connection equal to one we think exists
2100 * Solution: Keep both and postpone disambiguation. In the meantime
2101 * the connection will time out or peer will inform us it is broken.
2104 * - Use explicit duplicate.
2105 * - Accept new conn and destroy the old. (interruption in higher level)
2106 * - Keep the one with higher ID / created by peer with higher ID. */
2107 schedule_check_duplicates (c);
2110 if (CADET_TUNNEL_NEW == GCT_get_cstate (c->t))
2111 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
2113 send_connection_ack (c, GNUNET_NO);
2114 if (CADET_CONNECTION_SENT == c->state)
2115 connection_change_state (c, CADET_CONNECTION_ACK);
2119 /* It's for somebody else! Retransmit. */
2120 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
2121 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
2122 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
2123 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c,
2124 GNUNET_YES, GNUNET_YES,
2127 path_destroy (path);
2128 GCC_check_connections ();
2134 * Core handler for path confirmations.
2136 * @param cls closure
2137 * @param message message
2138 * @param peer peer identity this notification is about
2139 * @return #GNUNET_OK to keep the connection open,
2140 * #GNUNET_SYSERR to close it (signal serious error)
2143 GCC_handle_confirm (void *cls,
2144 const struct GNUNET_PeerIdentity *peer,
2145 const struct GNUNET_MessageHeader *message)
2147 struct GNUNET_CADET_ConnectionACK *msg;
2148 struct CadetConnection *c;
2149 struct CadetPeerPath *p;
2150 struct CadetPeer *pi;
2151 enum CadetConnectionState oldstate;
2154 GCC_check_connections ();
2155 msg = (struct GNUNET_CADET_ConnectionACK *) message;
2156 log_message (message, peer, &msg->cid);
2157 c = connection_get (&msg->cid);
2160 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
2162 LOG (GNUNET_ERROR_TYPE_DEBUG,
2163 " don't know the connection!\n");
2164 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2165 GCC_check_connections ();
2169 if (GNUNET_NO != c->destroy)
2171 GNUNET_assert (CADET_CONNECTION_DESTROYED == c->state);
2172 LOG (GNUNET_ERROR_TYPE_DEBUG,
2173 "connection %s being destroyed, ignoring confirm\n",
2175 GCC_check_connections ();
2179 oldstate = c->state;
2180 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
2181 pi = GCP_get (peer, GNUNET_YES);
2182 if (get_next_hop (c) == pi)
2184 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
2186 if (CADET_CONNECTION_SENT == oldstate)
2187 connection_change_state (c, CADET_CONNECTION_ACK);
2189 else if (get_prev_hop (c) == pi)
2191 LOG (GNUNET_ERROR_TYPE_DEBUG, " FINAL ACK\n");
2193 connection_change_state (c, CADET_CONNECTION_READY);
2197 GNUNET_break_op (0);
2201 connection_reset_timeout (c, fwd);
2203 /* Add path to peers? */
2207 GCP_add_path_to_all (p, GNUNET_YES);
2214 /* Message for us as creator? */
2215 if (GCC_is_origin (c, GNUNET_YES))
2217 if (GNUNET_NO != fwd)
2219 GNUNET_break_op (0);
2222 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
2224 /* If just created, cancel the short timeout and start a long one */
2225 if (CADET_CONNECTION_SENT == oldstate)
2226 connection_reset_timeout (c, GNUNET_YES);
2228 /* Change connection state */
2229 connection_change_state (c, CADET_CONNECTION_READY);
2230 send_connection_ack (c, GNUNET_YES);
2232 /* Change tunnel state, trigger KX */
2233 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2234 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2235 GCC_check_connections ();
2239 /* Message for us as destination? */
2240 if (GCC_is_terminal (c, GNUNET_YES))
2242 if (GNUNET_YES != fwd)
2244 GNUNET_break_op (0);
2247 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
2249 /* If just created, cancel the short timeout and start a long one */
2250 if (CADET_CONNECTION_ACK == oldstate)
2251 connection_reset_timeout (c, GNUNET_NO);
2253 /* Change tunnel state */
2254 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2255 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2256 GCC_check_connections ();
2260 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2261 GNUNET_assert (NULL ==
2262 GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2263 GNUNET_YES, NULL, NULL));
2264 GCC_check_connections ();
2270 * Core handler for notifications of broken connections.
2272 * @param cls Closure (unused).
2273 * @param id Peer identity of sending neighbor.
2274 * @param message Message.
2275 * @return #GNUNET_OK to keep the connection open,
2276 * #GNUNET_SYSERR to close it (signal serious error)
2279 GCC_handle_broken (void* cls,
2280 const struct GNUNET_PeerIdentity* id,
2281 const struct GNUNET_MessageHeader* message)
2283 struct GNUNET_CADET_ConnectionBroken *msg;
2284 struct CadetConnection *c;
2285 struct CadetTunnel *t;
2289 GCC_check_connections ();
2290 msg = (struct GNUNET_CADET_ConnectionBroken *) message;
2291 log_message (message, id, &msg->cid);
2292 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2293 GNUNET_i2s (&msg->peer1));
2294 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2295 GNUNET_i2s (&msg->peer2));
2296 c = connection_get (&msg->cid);
2299 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
2300 GCC_check_connections ();
2306 fwd = is_fwd (c, id);
2308 if (GCC_is_terminal (c, fwd))
2310 struct CadetPeer *endpoint;
2314 /* A terminal connection should not have 't' set to NULL. */
2316 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
2319 endpoint = GCP_get_short (c->path->peers[c->path->length - 1], GNUNET_YES);
2320 if (2 < c->path->length)
2321 path_invalidate (c->path);
2322 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
2324 c->state = CADET_CONNECTION_BROKEN;
2325 GCT_remove_connection (t, c);
2328 pending = c->pending_messages;
2330 resend_messages_and_destroy (c, !fwd);
2336 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2337 GNUNET_YES, NULL, NULL));
2338 connection_cancel_queues (c, !fwd);
2340 GCC_check_connections ();
2346 * Core handler for tunnel destruction
2348 * @param cls Closure (unused).
2349 * @param peer Peer identity of sending neighbor.
2350 * @param message Message.
2351 * @return #GNUNET_OK to keep the connection open,
2352 * #GNUNET_SYSERR to close it (signal serious error)
2355 GCC_handle_destroy (void *cls,
2356 const struct GNUNET_PeerIdentity *peer,
2357 const struct GNUNET_MessageHeader *message)
2359 const struct GNUNET_CADET_ConnectionDestroy *msg;
2360 struct CadetConnection *c;
2363 GCC_check_connections ();
2364 msg = (const struct GNUNET_CADET_ConnectionDestroy *) message;
2365 log_message (message, peer, &msg->cid);
2366 c = connection_get (&msg->cid);
2369 /* Probably already got the message from another path,
2370 * destroyed the tunnel and retransmitted to children.
2373 GNUNET_STATISTICS_update (stats,
2374 "# control on unknown connection",
2376 LOG (GNUNET_ERROR_TYPE_DEBUG,
2377 " connection unknown: already destroyed?\n");
2378 GCC_check_connections ();
2381 fwd = is_fwd (c, peer);
2382 if (GNUNET_SYSERR == fwd)
2384 GNUNET_break_op (0); /* FIXME */
2387 if (GNUNET_NO == GCC_is_terminal (c, fwd))
2389 GNUNET_assert (NULL ==
2390 GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2391 GNUNET_YES, NULL, NULL));
2393 else if (0 == c->pending_messages)
2395 LOG (GNUNET_ERROR_TYPE_DEBUG, " directly destroying connection!\n");
2397 GCC_check_connections ();
2403 GCT_remove_connection (c->t, c);
2406 GCC_check_connections ();
2412 * Check the message against internal state and test if it goes FWD or BCK.
2414 * Updates the PID, state and timeout values for the connection.
2416 * @param message Message to check. It must belong to an existing connection.
2417 * @param minimum_size The message cannot be smaller than this value.
2418 * @param cid Connection ID (even if @a c is NULL, the ID is still needed).
2419 * @param c Connection this message should belong. If NULL, check fails.
2420 * @param neighbor Neighbor that sent the message.
2423 check_message (const struct GNUNET_MessageHeader *message,
2424 size_t minimum_size,
2425 const struct GNUNET_CADET_Hash* cid,
2426 struct CadetConnection *c,
2427 const struct GNUNET_PeerIdentity *neighbor,
2430 GNUNET_PEER_Id neighbor_id;
2431 struct CadetFlowControl *fc;
2432 struct CadetPeer *hop;
2437 if (ntohs (message->size) < minimum_size)
2439 GNUNET_break_op (0);
2440 LOG (GNUNET_ERROR_TYPE_WARNING, "Size %u < %u\n",
2441 ntohs (message->size), minimum_size);
2442 return GNUNET_SYSERR;
2445 /* Check connection */
2448 GNUNET_STATISTICS_update (stats,
2449 "# unknown connection",
2451 LOG (GNUNET_ERROR_TYPE_DEBUG,
2452 "%s on unknown connection %s\n",
2453 GC_m2s (ntohs (message->type)),
2454 GNUNET_h2s (GC_h2hc (cid)));
2455 send_broken_unknown (cid,
2459 return GNUNET_SYSERR;
2462 /* Check if origin is as expected */
2463 neighbor_id = GNUNET_PEER_search (neighbor);
2464 hop = get_prev_hop (c);
2465 if (neighbor_id == GCP_get_short_id (hop))
2471 hop = get_next_hop (c);
2472 GNUNET_break (hop == c->next_peer);
2473 if (neighbor_id == GCP_get_short_id (hop))
2479 /* Unexpected peer sending traffic on a connection. */
2480 GNUNET_break_op (0);
2481 return GNUNET_SYSERR;
2485 /* Check PID for payload messages */
2486 type = ntohs (message->type);
2487 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type
2488 || GNUNET_MESSAGE_TYPE_CADET_AX == type)
2490 fc = fwd ? &c->bck_fc : &c->fwd_fc;
2491 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u - %u)\n",
2492 pid, fc->last_pid_recv + 1, fc->last_ack_sent);
2493 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
2495 GNUNET_break_op (0);
2496 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
2497 LOG (GNUNET_ERROR_TYPE_WARNING, "Received PID %u, (prev %u), ACK %u\n",
2498 pid, fc->last_pid_recv, fc->last_ack_sent);
2499 return GNUNET_SYSERR;
2501 if (GC_is_pid_bigger (pid, fc->last_pid_recv))
2505 delta = pid - fc->last_pid_recv;
2506 fc->last_pid_recv = pid;
2507 fc->recv_bitmap <<= delta;
2508 fc->recv_bitmap |= 1;
2512 GNUNET_STATISTICS_update (stats, "# out of order PID", 1, GNUNET_NO);
2513 if (GNUNET_NO == is_ooo_ok (fc->last_pid_recv, pid, fc->recv_bitmap))
2515 LOG (GNUNET_ERROR_TYPE_WARNING, "PID %u unexpected (%u+), dropping!\n",
2516 pid, fc->last_pid_recv - 31);
2517 return GNUNET_SYSERR;
2519 fc->recv_bitmap |= get_recv_bitmask (fc->last_pid_recv, pid);
2523 /* Count as connection confirmation. */
2524 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2526 connection_change_state (c, CADET_CONNECTION_READY);
2529 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2530 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2533 connection_reset_timeout (c, fwd);
2540 * Generic handler for cadet network encrypted traffic.
2542 * @param peer Peer identity this notification is about.
2543 * @param msg Encrypted message.
2544 * @return #GNUNET_OK to keep the connection open,
2545 * #GNUNET_SYSERR to close it (signal serious error)
2548 handle_cadet_encrypted (const struct GNUNET_PeerIdentity *peer,
2549 const struct GNUNET_MessageHeader *message)
2551 const struct GNUNET_CADET_Encrypted *otr_msg;
2552 const struct GNUNET_CADET_AX *ax_msg;
2553 const struct GNUNET_CADET_Hash* cid;
2554 struct CadetConnection *c;
2555 size_t minimum_size;
2561 GCC_check_connections ();
2562 if (GNUNET_MESSAGE_TYPE_CADET_AX == ntohs (message->type))
2564 overhead = sizeof (struct GNUNET_CADET_AX);
2565 ax_msg = (const struct GNUNET_CADET_AX *) message;
2567 pid = ntohl (ax_msg->pid);
2572 overhead = sizeof (struct GNUNET_CADET_Encrypted);
2573 otr_msg = (const struct GNUNET_CADET_Encrypted *) message;
2574 cid = &otr_msg->cid;
2575 pid = ntohl (otr_msg->pid);
2578 log_message (message, peer, cid);
2580 minimum_size = sizeof (struct GNUNET_MessageHeader) + overhead;
2581 c = connection_get (cid);
2582 fwd = check_message (message,
2589 /* If something went wrong, discard message. */
2590 if (GNUNET_SYSERR == fwd)
2592 GCC_check_connections ();
2596 /* Is this message for us? */
2597 if (GCC_is_terminal (c, fwd))
2599 GNUNET_STATISTICS_update (stats, "# received encrypted", 1, GNUNET_NO);
2603 GNUNET_break (GNUNET_NO != c->destroy);
2606 GCT_handle_encrypted (c->t, message);
2607 GCC_send_ack (c, fwd, GNUNET_NO);
2608 GCC_check_connections ();
2612 /* Message not for us: forward to next hop */
2613 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2614 if (NULL != otr_msg) /* only otr has ttl */
2616 ttl = ntohl (otr_msg->ttl);
2617 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
2620 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
2621 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
2622 GCC_send_ack (c, fwd, GNUNET_NO);
2623 GCC_check_connections ();
2628 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2629 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2630 GNUNET_NO, NULL, NULL));
2631 GCC_check_connections ();
2637 * Generic handler for cadet network encrypted traffic.
2639 * @param peer Peer identity this notification is about.
2640 * @param msg Encrypted message.
2641 * @return #GNUNET_OK to keep the connection open,
2642 * #GNUNET_SYSERR to close it (signal serious error)
2645 handle_cadet_kx (const struct GNUNET_PeerIdentity *peer,
2646 const struct GNUNET_CADET_KX *msg)
2648 const struct GNUNET_CADET_Hash* cid;
2649 struct CadetConnection *c;
2650 size_t expected_size;
2653 GCC_check_connections ();
2655 log_message (&msg->header, peer, cid);
2657 expected_size = sizeof (struct GNUNET_CADET_KX)
2658 + sizeof (struct GNUNET_MessageHeader);
2659 c = connection_get (cid);
2660 fwd = check_message (&msg->header,
2667 /* If something went wrong, discard message. */
2668 if (GNUNET_SYSERR == fwd)
2671 /* Is this message for us? */
2672 if (GCC_is_terminal (c, fwd))
2674 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2675 GNUNET_STATISTICS_update (stats, "# received KX", 1, GNUNET_NO);
2681 GCT_handle_kx (c->t, &msg[1].header);
2682 GCC_check_connections ();
2686 /* Message not for us: forward to next hop */
2687 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2688 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2689 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2690 GNUNET_NO, NULL, NULL));
2691 GCC_check_connections ();
2697 * Core handler for key exchange traffic (ephemeral key, ping, pong).
2699 * @param cls Closure (unused).
2700 * @param message Message received.
2701 * @param peer Peer who sent the message.
2702 * @return #GNUNET_OK to keep the connection open,
2703 * #GNUNET_SYSERR to close it (signal serious error)
2706 GCC_handle_kx (void *cls,
2707 const struct GNUNET_PeerIdentity *peer,
2708 const struct GNUNET_MessageHeader *message)
2710 GCC_check_connections ();
2711 return handle_cadet_kx (peer, (struct GNUNET_CADET_KX *) message);
2716 * Core handler for encrypted cadet network traffic (channel mgmt, data).
2718 * @param cls Closure (unused).
2719 * @param message Message received.
2720 * @param peer Peer who sent the message.
2721 * @return #GNUNET_OK to keep the connection open,
2722 * #GNUNET_SYSERR to close it (signal serious error)
2725 GCC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
2726 const struct GNUNET_MessageHeader *message)
2728 GCC_check_connections ();
2729 return handle_cadet_encrypted (peer, message);
2734 * Core handler for cadet network traffic point-to-point acks.
2736 * @param cls closure
2737 * @param message message
2738 * @param peer peer identity this notification is about
2739 * @return #GNUNET_OK to keep the connection open,
2740 * #GNUNET_SYSERR to close it (signal serious error)
2743 GCC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
2744 const struct GNUNET_MessageHeader *message)
2746 struct GNUNET_CADET_ACK *msg;
2747 struct CadetConnection *c;
2748 struct CadetFlowControl *fc;
2753 GCC_check_connections ();
2754 msg = (struct GNUNET_CADET_ACK *) message;
2755 log_message (message, peer, &msg->cid);
2756 c = connection_get (&msg->cid);
2759 GNUNET_STATISTICS_update (stats,
2760 "# ack on unknown connection",
2763 send_broken_unknown (&msg->cid,
2767 GCC_check_connections ();
2771 /* Is this a forward or backward ACK? */
2772 id = GNUNET_PEER_search (peer);
2773 if (GCP_get_short_id (get_next_hop (c)) == id)
2778 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2785 GNUNET_break_op (0);
2789 ack = ntohl (msg->ack);
2790 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s ACK %u (was %u)\n",
2791 GC_f2s (fwd), ack, fc->last_ack_recv);
2792 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2793 fc->last_ack_recv = ack;
2795 /* Cancel polling if the ACK is big enough. */
2796 if (NULL != fc->poll_task &&
2797 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2799 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2800 GNUNET_SCHEDULER_cancel (fc->poll_task);
2801 fc->poll_task = NULL;
2802 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2805 connection_unlock_queue (c, fwd);
2806 GCC_check_connections ();
2812 * Core handler for cadet network traffic point-to-point ack polls.
2814 * @param cls closure
2815 * @param message message
2816 * @param peer peer identity this notification is about
2817 * @return #GNUNET_OK to keep the connection open,
2818 * #GNUNET_SYSERR to close it (signal serious error)
2821 GCC_handle_poll (void *cls,
2822 const struct GNUNET_PeerIdentity *peer,
2823 const struct GNUNET_MessageHeader *message)
2825 struct GNUNET_CADET_Poll *msg;
2826 struct CadetConnection *c;
2827 struct CadetFlowControl *fc;
2832 GCC_check_connections ();
2833 msg = (struct GNUNET_CADET_Poll *) message;
2834 log_message (message, peer, &msg->cid);
2835 c = connection_get (&msg->cid);
2838 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2840 LOG (GNUNET_ERROR_TYPE_DEBUG,
2841 "POLL message on unknown connection %s!\n",
2842 GNUNET_h2s (GC_h2hc (&msg->cid)));
2843 send_broken_unknown (&msg->cid,
2847 GCC_check_connections ();
2851 /* Is this a forward or backward ACK?
2852 * Note: a poll should never be needed in a loopback case,
2853 * since there is no possiblility of packet loss there, so
2854 * this way of discerining FWD/BCK should not be a problem.
2856 id = GNUNET_PEER_search (peer);
2857 if (GCP_get_short_id (get_next_hop (c)) == id)
2859 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2862 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2864 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2869 GNUNET_break_op (0);
2873 pid = ntohl (msg->pid);
2874 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2875 fc->last_pid_recv = pid;
2876 fwd = fc == &c->bck_fc;
2877 GCC_send_ack (c, fwd, GNUNET_YES);
2878 GCC_check_connections ();
2885 * Send an ACK on the appropriate connection/channel, depending on
2886 * the direction and the position of the peer.
2888 * @param c Which connection to send the hop-by-hop ACK.
2889 * @param fwd Is this a fwd ACK? (will go dest->root).
2890 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2893 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
2895 unsigned int buffer;
2897 GCC_check_connections ();
2898 LOG (GNUNET_ERROR_TYPE_DEBUG, "GCC send %s ACK on %s\n",
2899 GC_f2s (fwd), GCC_2s (c));
2907 if (GNUNET_NO != c->destroy)
2909 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2910 GCC_check_connections ();
2914 /* Get available buffer space */
2915 if (GCC_is_terminal (c, fwd))
2917 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2918 buffer = GCT_get_channels_buffer (c->t);
2922 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2923 buffer = GCC_get_buffer (c, fwd);
2925 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2926 if (0 == buffer && GNUNET_NO == force)
2928 GCC_check_connections ();
2932 /* Send available buffer space */
2933 if (GCC_is_origin (c, fwd))
2935 GNUNET_assert (NULL != c->t);
2936 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2937 GCT_unchoke_channels (c->t);
2941 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2942 send_ack (c, buffer, fwd, force);
2944 GCC_check_connections ();
2949 * Initialize the connections subsystem
2951 * @param c Configuration handle.
2954 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2956 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2958 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2961 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2962 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2963 GNUNET_SCHEDULER_shutdown ();
2968 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2971 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2972 "CADET", "MAX_CONNECTIONS", "MISSING");
2973 GNUNET_SCHEDULER_shutdown ();
2978 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2979 &refresh_connection_time))
2981 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2982 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2983 GNUNET_SCHEDULER_shutdown ();
2986 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2987 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2992 * Destroy each connection on shutdown.
2994 * @param cls Closure (unused).
2995 * @param key Current key code (CID, unused).
2996 * @param value Value in the hash map (`struct CadetConnection`)
2998 * @return #GNUNET_YES, because we should continue to iterate
3001 shutdown_iterator (void *cls,
3002 const struct GNUNET_HashCode *key,
3005 struct CadetConnection *c = value;
3007 c->state = CADET_CONNECTION_DESTROYED;
3014 * Shut down the connections subsystem.
3019 LOG (GNUNET_ERROR_TYPE_DEBUG, "Shutting down connections\n");
3020 GCC_check_connections ();
3021 GNUNET_CONTAINER_multihashmap_iterate (connections,
3024 GNUNET_CONTAINER_multihashmap_destroy (connections);
3030 * Create a connection.
3032 * @param cid Connection ID (either created locally or imposed remotely).
3033 * @param t Tunnel this connection belongs to (or NULL);
3034 * @param path Path this connection has to use (copy is made).
3035 * @param own_pos Own position in the @c path path.
3037 * @return Newly created connection, NULL in case of error (own id not in path).
3039 struct CadetConnection *
3040 GCC_new (const struct GNUNET_CADET_Hash *cid,
3041 struct CadetTunnel *t,
3042 struct CadetPeerPath *path,
3043 unsigned int own_pos)
3045 struct CadetConnection *c;
3046 struct CadetPeerPath *cpath;
3048 GCC_check_connections ();
3049 cpath = path_duplicate (path);
3050 GNUNET_assert (NULL != cpath);
3051 c = GNUNET_new (struct CadetConnection);
3053 GNUNET_assert (GNUNET_OK ==
3054 GNUNET_CONTAINER_multihashmap_put (connections,
3056 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
3057 fc_init (&c->fwd_fc);
3058 fc_init (&c->bck_fc);
3063 GNUNET_assert (own_pos <= cpath->length - 1);
3064 c->own_pos = own_pos;
3067 if (GNUNET_OK != register_neighbors (c))
3071 /* We were the origin of this request, this means we have invalid
3072 * info about the paths to reach the destination. We must invalidate
3073 * the *original* path to avoid trying it again in the next minute.
3075 if (2 < path->length)
3076 path_invalidate (path);
3080 GCT_debug(t, GNUNET_ERROR_TYPE_WARNING);
3084 path_destroy (c->path);
3089 LOG (GNUNET_ERROR_TYPE_INFO, "New connection %s\n", GCC_2s (c));
3090 GCC_check_connections ();
3096 GCC_destroy (struct CadetConnection *c)
3098 GCC_check_connections ();
3105 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
3106 return; /* -> message_sent -> GCC_destroy. Don't loop. */
3109 LOG (GNUNET_ERROR_TYPE_DEBUG,
3110 "destroying connection %s\n",
3112 LOG (GNUNET_ERROR_TYPE_DEBUG,
3113 " fc's f: %p, b: %p\n",
3114 &c->fwd_fc, &c->bck_fc);
3115 LOG (GNUNET_ERROR_TYPE_DEBUG,
3116 " fc tasks f: %u, b: %u\n",
3117 c->fwd_fc.poll_task,
3118 c->bck_fc.poll_task);
3120 /* Cancel all traffic */
3121 if (NULL != c->path)
3123 connection_cancel_queues (c, GNUNET_YES);
3124 connection_cancel_queues (c, GNUNET_NO);
3126 unregister_neighbors (c);
3127 path_destroy (c->path);
3130 /* Delete from tunnel */
3132 GCT_remove_connection (c->t, c);
3134 if (NULL != c->check_duplicates_task)
3135 GNUNET_SCHEDULER_cancel (c->check_duplicates_task);
3136 if (NULL != c->fwd_maintenance_task)
3137 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
3138 if (NULL != c->bck_maintenance_task)
3139 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
3141 if (GNUNET_NO == c->was_removed)
3143 GNUNET_break (GNUNET_YES ==
3144 GNUNET_CONTAINER_multihashmap_remove (connections,
3148 GNUNET_STATISTICS_update (stats,
3153 GCC_check_connections ();
3158 * Get the connection ID.
3160 * @param c Connection to get the ID from.
3162 * @return ID of the connection.
3164 const struct GNUNET_CADET_Hash *
3165 GCC_get_id (const struct CadetConnection *c)
3172 * Get the connection ID.
3174 * @param c Connection to get the ID from.
3176 * @return ID of the connection.
3178 const struct GNUNET_HashCode *
3179 GCC_get_h (const struct CadetConnection *c)
3181 return GC_h2hc (&c->id);
3186 * Get the connection path.
3188 * @param c Connection to get the path from.
3190 * @return path used by the connection.
3192 const struct CadetPeerPath *
3193 GCC_get_path (const struct CadetConnection *c)
3195 if (GNUNET_NO == c->destroy)
3202 * Get the connection state.
3204 * @param c Connection to get the state from.
3206 * @return state of the connection.
3208 enum CadetConnectionState
3209 GCC_get_state (const struct CadetConnection *c)
3215 * Get the connection tunnel.
3217 * @param c Connection to get the tunnel from.
3219 * @return tunnel of the connection.
3221 struct CadetTunnel *
3222 GCC_get_tunnel (const struct CadetConnection *c)
3229 * Get free buffer space in a connection.
3231 * @param c Connection.
3232 * @param fwd Is query about FWD traffic?
3234 * @return Free buffer space [0 - max_msgs_queue/max_connections]
3237 GCC_get_buffer (struct CadetConnection *c, int fwd)
3239 struct CadetFlowControl *fc;
3241 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3243 LOG (GNUNET_ERROR_TYPE_DEBUG, " Get %s buffer on %s: %u - %u\n",
3244 GC_f2s (fwd), GCC_2s (c), fc->queue_max, fc->queue_n);
3245 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
3247 return (fc->queue_max - fc->queue_n);
3252 * Get how many messages have we allowed to send to us from a direction.
3254 * @param c Connection.
3255 * @param fwd Are we asking about traffic from FWD (BCK messages)?
3257 * @return last_ack_sent - last_pid_recv
3260 GCC_get_allowed (struct CadetConnection *c, int fwd)
3262 struct CadetFlowControl *fc;
3264 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3265 if (CADET_CONNECTION_READY != c->state
3266 || GC_is_pid_bigger (fc->last_pid_recv, fc->last_ack_sent))
3270 return (fc->last_ack_sent - fc->last_pid_recv);
3275 * Get messages queued in a connection.
3277 * @param c Connection.
3278 * @param fwd Is query about FWD traffic?
3280 * @return Number of messages queued.
3283 GCC_get_qn (struct CadetConnection *c, int fwd)
3285 struct CadetFlowControl *fc;
3287 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3294 * Get next PID to use.
3296 * @param c Connection.
3297 * @param fwd Is query about FWD traffic?
3299 * @return Last PID used + 1.
3302 GCC_get_pid (struct CadetConnection *c, int fwd)
3304 struct CadetFlowControl *fc;
3306 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3308 return fc->last_pid_sent + 1;
3313 * Allow the connection to advertise a buffer of the given size.
3315 * The connection will send an @c fwd ACK message (so: in direction !fwd)
3316 * allowing up to last_pid_recv + buffer.
3318 * @param c Connection.
3319 * @param buffer How many more messages the connection can accept.
3320 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
3323 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
3325 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
3326 GCC_2s (c), buffer, GC_f2s (fwd));
3327 send_ack (c, buffer, fwd, GNUNET_NO);
3332 * Notify other peers on a connection of a broken link. Mark connections
3333 * to destroy after all traffic has been sent.
3335 * @param c Connection on which there has been a disconnection.
3336 * @param peer Peer that disconnected.
3339 GCC_neighbor_disconnected (struct CadetConnection *c, struct CadetPeer *peer)
3341 struct CadetFlowControl *fc;
3342 struct CadetPeer *hop;
3346 GCC_check_connections ();
3347 strncpy (peer_name, GCP_2s (peer), 16);
3348 peer_name[15] = '\0';
3349 LOG (GNUNET_ERROR_TYPE_DEBUG,
3350 "shutting down %s, %s disconnected\n",
3351 GCC_2s (c), peer_name);
3353 invalidate_paths (c, peer);
3355 hop = get_prev_hop (c);
3358 /* Path was NULL, we should have deleted the connection. */
3362 fwd = (peer == hop);
3363 if ( (GNUNET_YES == GCC_is_terminal (c, fwd)) ||
3364 (GNUNET_NO != c->destroy) )
3366 /* Local shutdown, or other peer already down (hence 'c->destroy');
3367 so there is no one to notify about this, just clean up. */
3369 GCC_check_connections ();
3372 /* Mark FlowControl towards the peer as unavaliable. */
3373 fc = fwd ? &c->bck_fc : &c->fwd_fc;
3376 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
3378 /* Connection will have at least one pending message
3379 * (the one we just scheduled), so delay destruction
3380 * and remove from map so we don't use accidentally. */
3382 GNUNET_assert (GNUNET_NO == c->was_removed);
3383 c->was_removed = GNUNET_YES;
3384 GNUNET_break (GNUNET_YES ==
3385 GNUNET_CONTAINER_multihashmap_remove (connections,
3388 /* Cancel queue in the direction that just died. */
3389 connection_cancel_queues (c, ! fwd);
3390 GCC_stop_poll (c, ! fwd);
3391 unregister_neighbors (c);
3392 GCC_check_connections ();
3397 * Is this peer the first one on the connection?
3399 * @param c Connection.
3400 * @param fwd Is this about fwd traffic?
3402 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
3405 GCC_is_origin (struct CadetConnection *c, int fwd)
3407 if (!fwd && c->path->length - 1 == c->own_pos )
3409 if (fwd && 0 == c->own_pos)
3416 * Is this peer the last one on the connection?
3418 * @param c Connection.
3419 * @param fwd Is this about fwd traffic?
3420 * Note that the ROOT is the terminal for BCK traffic!
3422 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
3425 GCC_is_terminal (struct CadetConnection *c, int fwd)
3427 return GCC_is_origin (c, ! fwd);
3432 * See if we are allowed to send by the next hop in the given direction.
3434 * @param c Connection.
3435 * @param fwd Is this about fwd traffic?
3437 * @return #GNUNET_YES in case it's OK to send.
3440 GCC_is_sendable (struct CadetConnection *c, int fwd)
3442 struct CadetFlowControl *fc;
3444 LOG (GNUNET_ERROR_TYPE_DEBUG,
3445 " checking sendability of %s traffic on %s\n",
3446 GC_f2s (fwd), GCC_2s (c));
3452 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3453 LOG (GNUNET_ERROR_TYPE_DEBUG,
3454 " last ack recv: %u, last pid sent: %u\n",
3455 fc->last_ack_recv, fc->last_pid_sent);
3456 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
3458 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
3461 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
3467 * Check if this connection is a direct one (never trim a direct connection).
3469 * @param c Connection.
3471 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
3474 GCC_is_direct (struct CadetConnection *c)
3476 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
3481 * Sends an already built message on a connection, properly registering
3482 * all used resources.
3484 * @param message Message to send. Function makes a copy of it.
3485 * If message is not hop-by-hop, decrements TTL of copy.
3486 * @param payload_type Type of payload, in case the message is encrypted.
3487 * @param c Connection on which this message is transmitted.
3488 * @param fwd Is this a fwd message?
3489 * @param force Force the connection to accept the message (buffer overfill).
3490 * @param cont Continuation called once message is sent. Can be NULL.
3491 * @param cont_cls Closure for @c cont.
3493 * @return Handle to cancel the message before it's sent.
3494 * NULL on error or if @c cont is NULL.
3495 * Invalid on @c cont call.
3497 struct CadetConnectionQueue *
3498 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
3499 uint16_t payload_type, uint32_t payload_id,
3500 struct CadetConnection *c, int fwd, int force,
3501 GCC_sent cont, void *cont_cls)
3503 struct CadetFlowControl *fc;
3504 struct CadetConnectionQueue *q;
3510 GCC_check_connections ();
3511 size = ntohs (message->size);
3512 data = GNUNET_malloc (size);
3513 memcpy (data, message, size);
3514 type = ntohs (message->type);
3515 LOG (GNUNET_ERROR_TYPE_INFO,
3516 "--> %s (%s %4u) on conn %s (%p) %s [%5u]\n",
3517 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), c,
3520 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3521 if (0 == fc->queue_max)
3526 droppable = GNUNET_NO == force;
3529 struct GNUNET_CADET_AX *axmsg;
3530 struct GNUNET_CADET_Encrypted *emsg;
3531 struct GNUNET_CADET_KX *kmsg;
3532 struct GNUNET_CADET_ACK *amsg;
3533 struct GNUNET_CADET_Poll *pmsg;
3534 struct GNUNET_CADET_ConnectionDestroy *dmsg;
3535 struct GNUNET_CADET_ConnectionBroken *bmsg;
3538 case GNUNET_MESSAGE_TYPE_CADET_AX:
3539 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
3540 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
3542 emsg = (struct GNUNET_CADET_Encrypted *) data;
3543 ttl = ntohl (emsg->ttl);
3546 GNUNET_break_op (0);
3551 emsg->ttl = htonl (ttl - 1);
3555 axmsg = (struct GNUNET_CADET_AX *) data;
3558 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
3559 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
3560 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
3561 if (GNUNET_YES == droppable)
3567 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
3571 case GNUNET_MESSAGE_TYPE_CADET_KX:
3572 kmsg = (struct GNUNET_CADET_KX *) data;
3576 case GNUNET_MESSAGE_TYPE_CADET_ACK:
3577 amsg = (struct GNUNET_CADET_ACK *) data;
3579 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
3580 droppable = GNUNET_NO;
3583 case GNUNET_MESSAGE_TYPE_CADET_POLL:
3584 pmsg = (struct GNUNET_CADET_Poll *) data;
3586 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL %u\n", ntohl (pmsg->pid));
3587 droppable = GNUNET_NO;
3590 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
3591 dmsg = (struct GNUNET_CADET_ConnectionDestroy *) data;
3595 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
3596 bmsg = (struct GNUNET_CADET_ConnectionBroken *) data;
3600 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
3601 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
3610 if (fc->queue_n > fc->queue_max && droppable)
3612 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
3615 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue full: %u/%u\n",
3616 fc->queue_n, fc->queue_max);
3617 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type
3618 || GNUNET_MESSAGE_TYPE_CADET_AX == type)
3623 return NULL; /* Drop this message */
3626 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %s %u\n",
3627 GCC_2s (c), c->pending_messages);
3628 c->pending_messages++;
3630 q = GNUNET_new (struct CadetConnectionQueue);
3631 q->forced = !droppable;
3632 q->q = GCP_queue_add (get_hop (c, fwd), data, type, payload_type, payload_id,
3633 size, c, fwd, &conn_message_sent, q);
3636 LOG (GNUNET_ERROR_TYPE_DEBUG, "dropping msg on %s, NULL q\n", GCC_2s (c));
3639 GCC_check_connections ();
3643 q->cont_cls = cont_cls;
3644 GCC_check_connections ();
3645 return (NULL == cont) ? NULL : q;
3650 * Cancel a previously sent message while it's in the queue.
3652 * ONLY can be called before the continuation given to the send function
3653 * is called. Once the continuation is called, the message is no longer in the
3656 * @param q Handle to the queue.
3659 GCC_cancel (struct CadetConnectionQueue *q)
3661 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GCC cancel message\n");
3663 /* queue destroy calls message_sent, which calls q->cont and frees q */
3664 GCP_queue_destroy (q->q, GNUNET_YES, GNUNET_NO, 0);
3665 GCC_check_connections ();
3670 * Sends a CREATE CONNECTION message for a path to a peer.
3671 * Changes the connection and tunnel states if necessary.
3673 * @param connection Connection to create.
3676 GCC_send_create (struct CadetConnection *connection)
3678 enum CadetTunnelCState state;
3681 GCC_check_connections ();
3682 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3683 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
3685 LOG (GNUNET_ERROR_TYPE_INFO, "==> %s %19s on conn %s (%p) FWD [%5u]\n",
3686 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE), "",
3687 GCC_2s (connection), connection, size);
3688 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3689 connection, connection->pending_messages);
3690 connection->pending_messages++;
3692 connection->maintenance_q =
3693 GCP_queue_add (get_next_hop (connection), NULL,
3694 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, UINT16_MAX, 0,
3695 size, connection, GNUNET_YES, &conn_message_sent, NULL);
3697 state = GCT_get_cstate (connection->t);
3698 if (CADET_TUNNEL_SEARCHING == state || CADET_TUNNEL_NEW == state)
3699 GCT_change_cstate (connection->t, CADET_TUNNEL_WAITING);
3700 if (CADET_CONNECTION_NEW == connection->state)
3701 connection_change_state (connection, CADET_CONNECTION_SENT);
3702 GCC_check_connections ();
3707 * Send a message to all peers in this connection that the connection
3708 * is no longer valid.
3710 * If some peer should not receive the message, it should be zero'ed out
3711 * before calling this function.
3713 * @param c The connection whose peers to notify.
3716 GCC_send_destroy (struct CadetConnection *c)
3718 struct GNUNET_CADET_ConnectionDestroy msg;
3720 if (GNUNET_YES == c->destroy)
3722 GCC_check_connections ();
3723 msg.header.size = htons (sizeof (msg));
3724 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
3726 LOG (GNUNET_ERROR_TYPE_DEBUG,
3727 " sending connection destroy for connection %s\n",
3730 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3731 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3733 GNUNET_YES, NULL, NULL));
3734 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3735 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3737 GNUNET_YES, NULL, NULL));
3739 GCC_check_connections ();
3744 * @brief Start a polling timer for the connection.
3746 * When a neighbor does not accept more traffic on the connection it could be
3747 * caused by a simple congestion or by a lost ACK. Polling enables to check
3748 * for the lastest ACK status for a connection.
3750 * @param c Connection.
3751 * @param fwd Should we poll in the FWD direction?
3754 GCC_start_poll (struct CadetConnection *c, int fwd)
3756 struct CadetFlowControl *fc;
3758 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3759 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL %s requested\n",
3761 if (NULL != fc->poll_task || NULL != fc->poll_msg)
3763 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL already in progress (t: %p, m: %p)\n",
3764 fc->poll_task, fc->poll_msg);
3767 if (0 == fc->queue_max)
3769 /* Should not be needed, traffic should've been cancelled. */
3771 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL not possible, peer disconnected\n");
3774 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL started on request\n");
3775 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
3782 * @brief Stop polling a connection for ACKs.
3784 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3786 * @param c Connection.
3787 * @param fwd Should we stop the poll in the FWD direction?
3790 GCC_stop_poll (struct CadetConnection *c, int fwd)
3792 struct CadetFlowControl *fc;
3794 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3795 if (NULL != fc->poll_task)
3797 GNUNET_SCHEDULER_cancel (fc->poll_task);
3798 fc->poll_task = NULL;
3800 if (NULL != fc->poll_msg)
3802 GCC_cancel (fc->poll_msg);
3803 fc->poll_msg = NULL;
3809 * Get a (static) string for a connection.
3811 * @param c Connection.
3814 GCC_2s (const struct CadetConnection *c)
3821 static char buf[128];
3823 SPRINTF (buf, "%s (->%s)",
3824 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3827 return GNUNET_h2s (GC_h2hc (&c->id));
3832 * Log all possible info about the connection state.
3834 * @param c Connection to debug.
3835 * @param level Debug level to use.
3838 GCC_debug (const struct CadetConnection *c, enum GNUNET_ErrorType level)
3843 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
3845 __FILE__, __FUNCTION__, __LINE__);
3851 LOG2 (level, "CCC DEBUG NULL CONNECTION\n");
3855 LOG2 (level, "CCC DEBUG CONNECTION %s\n", GCC_2s (c));
3856 s = path_2s (c->path);
3857 LOG2 (level, "CCC path %s, own pos: %u\n", s, c->own_pos);
3859 LOG2 (level, "CCC state: %s, destroy: %u\n",
3860 GCC_state2s (c->state), c->destroy);
3861 LOG2 (level, "CCC pending messages: %u\n", c->pending_messages);
3862 if (NULL != c->perf)
3863 LOG2 (level, "CCC us/byte: %f\n", c->perf->avg);
3865 LOG2 (level, "CCC FWD flow control:\n");
3866 LOG2 (level, "CCC queue: %u/%u\n", c->fwd_fc.queue_n, c->fwd_fc.queue_max);
3867 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3868 c->fwd_fc.last_pid_sent, c->fwd_fc.last_pid_recv);
3869 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3870 c->fwd_fc.last_ack_sent, c->fwd_fc.last_ack_recv);
3871 LOG2 (level, "CCC recv PID bitmap: %X\n", c->fwd_fc.recv_bitmap);
3872 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3873 c->fwd_fc.poll_task, c->fwd_fc.poll_msg, c->fwd_fc.ack_msg);
3875 LOG2 (level, "CCC BCK flow control:\n");
3876 LOG2 (level, "CCC queue: %u/%u\n", c->bck_fc.queue_n, c->bck_fc.queue_max);
3877 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3878 c->bck_fc.last_pid_sent, c->bck_fc.last_pid_recv);
3879 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3880 c->bck_fc.last_ack_sent, c->bck_fc.last_ack_recv);
3881 LOG2 (level, "CCC recv PID bitmap: %X\n", c->bck_fc.recv_bitmap);
3882 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3883 c->bck_fc.poll_task, c->bck_fc.poll_msg, c->bck_fc.ack_msg);
3885 LOG2 (level, "CCC DEBUG CONNECTION END\n");