2 This file is part of GNUnet.
3 Copyright (C) 2001-2015 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18 Boston, MA 02110-1301, USA.
21 * @file cadet/gnunet-service-cadet_connection.c
22 * @brief GNUnet CADET service connection handling
23 * @author Bartlomiej Polot
26 #include "gnunet_util_lib.h"
27 #include "gnunet_statistics_service.h"
28 #include "cadet_path.h"
29 #include "cadet_protocol.h"
31 #include "gnunet-service-cadet_connection.h"
32 #include "gnunet-service-cadet_peer.h"
33 #include "gnunet-service-cadet_tunnel.h"
37 * Should we run somewhat expensive checks on our invariants?
39 #define CHECK_INVARIANTS 0
42 #define LOG(level, ...) GNUNET_log_from (level,"cadet-con",__VA_ARGS__)
43 #define LOG2(level, ...) GNUNET_log_from_nocheck(level,"cadet-con",__VA_ARGS__)
46 #define CADET_MAX_POLL_TIME GNUNET_TIME_relative_multiply (\
47 GNUNET_TIME_UNIT_MINUTES,\
52 /******************************************************************************/
53 /******************************** STRUCTS **********************************/
54 /******************************************************************************/
57 * 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.
75 unsigned int queue_max;
78 * ID of the last packet sent towards the peer.
80 uint32_t last_pid_sent;
83 * ID of the last packet received from the peer.
85 uint32_t last_pid_recv;
88 * Bitmap of past 32 messages received:
89 * - LSB being @c last_pid_recv.
90 * - MSB being @c last_pid_recv - 31 (mod UINTMAX).
95 * Last ACK sent to the peer (peer can't send more than this PID).
97 uint32_t last_ack_sent;
100 * Last ACK sent towards the origin (for traffic towards leaf node).
102 uint32_t last_ack_recv;
105 * Task to poll the peer in case of a lost ACK causes stall.
107 struct GNUNET_SCHEDULER_Task *poll_task;
110 * How frequently to poll for ACKs.
112 struct GNUNET_TIME_Relative poll_time;
115 * Queued poll message, to cancel if not necessary anymore (got ACK).
117 struct CadetConnectionQueue *poll_msg;
120 * Queued poll message, to cancel if not necessary anymore (got ACK).
122 struct CadetConnectionQueue *ack_msg;
126 * Keep a record of the last messages sent on this connection.
128 struct CadetConnectionPerformance
131 * Circular buffer for storing measurements.
133 double usecsperbyte[AVG_MSGS];
136 * Running average of @c usecsperbyte.
141 * How many values of @c usecsperbyte are valid.
146 * Index of the next "free" position in @c usecsperbyte.
153 * Struct containing all information regarding a connection to a peer.
155 struct CadetConnection
158 * Tunnel this connection is part of.
160 struct CadetTunnel *t;
163 * Flow control information for traffic fwd.
165 struct CadetFlowControl fwd_fc;
168 * Flow control information for traffic bck.
170 struct CadetFlowControl bck_fc;
173 * Measure connection performance on the endpoint.
175 struct CadetConnectionPerformance *perf;
178 * ID of the connection.
180 struct GNUNET_CADET_Hash id;
183 * Path being used for the tunnel. At the origin of the connection
184 * it's a pointer to the destination's path pool, otherwise just a copy.
186 struct CadetPeerPath *path;
189 * Task to keep the used paths alive at the owner,
190 * time tunnel out on all the other peers.
192 struct GNUNET_SCHEDULER_Task *fwd_maintenance_task;
195 * Task to keep the used paths alive at the destination,
196 * time tunnel out on all the other peers.
198 struct GNUNET_SCHEDULER_Task *bck_maintenance_task;
201 * Queue handle for maintainance traffic. One handle for FWD and BCK since
202 * one peer never needs to maintain both directions (no loopback connections).
204 struct CadetPeerQueue *maintenance_q;
207 * Should equal #get_next_hop(), or NULL if that peer disconnected.
209 struct CadetPeer *next_peer;
212 * Should equal #get_prev_hop(), or NULL if that peer disconnected.
214 struct CadetPeer *prev_peer;
217 * State of the connection.
219 enum CadetConnectionState state;
222 * Position of the local peer in the path.
224 unsigned int own_pos;
227 * Pending message count.
229 unsigned int pending_messages;
233 * - if 0, connection in use.
234 * - if 1, destroy on last message.
235 * - if 2, connection is being destroyed don't re-enter.
240 * In-connection-map flag. Sometimes, when @e destroy is set but
241 * actual destruction is delayed to enable us to finish processing
242 * queues (i.e. in the direction that is still working), we remove
243 * the connection from the map to prevent it from still being
244 * found (and used) by accident. This flag is set to #GNUNET_YES
245 * for a connection that is not in the #connections map. Should
246 * only be #GNUNET_YES if #destroy is also non-zero.
251 * Counter to do exponential backoff when creating a connection (max 64).
253 unsigned short create_retry;
256 * Task to check if connection has duplicates.
258 struct GNUNET_SCHEDULER_Task *check_duplicates_task;
263 * Handle for messages queued but not yet sent.
265 struct CadetConnectionQueue
268 * Peer queue handle, to cancel if necessary.
270 struct CadetPeerQueue *q;
273 * Continuation to call once sent.
278 * Closure for @e cont.
283 * Was this a forced message? (Do not account for it)
288 /******************************************************************************/
289 /******************************* GLOBALS ***********************************/
290 /******************************************************************************/
293 * Global handle to the statistics service.
295 extern struct GNUNET_STATISTICS_Handle *stats;
298 * Local peer own ID (memory efficient handle).
300 extern GNUNET_PEER_Id myid;
303 * Local peer own ID (full value).
305 extern struct GNUNET_PeerIdentity my_full_id;
308 * Connections known, indexed by cid (CadetConnection).
310 static struct GNUNET_CONTAINER_MultiHashMap *connections;
313 * How many connections are we willing to maintain.
314 * Local connections are always allowed, even if there are more connections than max.
316 static unsigned long long max_connections;
319 * How many messages *in total* are we willing to queue, divide by number of
320 * connections to get connection queue size.
322 static unsigned long long max_msgs_queue;
325 * How often to send path keepalives. Paths timeout after 4 missed.
327 static struct GNUNET_TIME_Relative refresh_connection_time;
330 * How often to send path create / ACKs.
332 static struct GNUNET_TIME_Relative create_connection_time;
335 /******************************************************************************/
336 /******************************** STATIC ***********************************/
337 /******************************************************************************/
341 #if 0 // avoid compiler warning for unused static function
343 fc_debug (struct CadetFlowControl *fc)
345 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
346 fc->last_pid_recv, fc->last_ack_sent);
347 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
348 fc->last_pid_sent, fc->last_ack_recv);
349 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
350 fc->queue_n, fc->queue_max);
354 connection_debug (struct CadetConnection *c)
358 LOG (GNUNET_ERROR_TYPE_INFO, "DEBUG NULL CONNECTION\n");
361 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
362 peer2s (c->t->peer), GCC_2s (c));
363 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
364 c->state, c->pending_messages);
365 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
366 fc_debug (&c->fwd_fc);
367 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
368 fc_debug (&c->bck_fc);
374 * Schedule next keepalive task, taking in consideration
375 * the connection state and number of retries.
377 * @param c Connection for which to schedule the next keepalive.
378 * @param fwd Direction for the next keepalive.
381 schedule_next_keepalive (struct CadetConnection *c, int fwd);
385 * Resets the connection timeout task, some other message has done the
387 * - For the first peer on the direction this means to send
388 * a keepalive or a path confirmation message (either create or ACK).
389 * - For all other peers, this means to destroy the connection,
390 * due to lack of activity.
391 * Starts the timeout if no timeout was running (connection just created).
393 * @param c Connection whose timeout to reset.
394 * @param fwd Is this forward?
397 connection_reset_timeout (struct CadetConnection *c, int fwd);
401 * Get string description for tunnel state. Reentrant.
403 * @param s Tunnel state.
405 * @return String representation.
408 GCC_state2s (enum CadetConnectionState s)
412 case CADET_CONNECTION_NEW:
413 return "CADET_CONNECTION_NEW";
414 case CADET_CONNECTION_SENT:
415 return "CADET_CONNECTION_SENT";
416 case CADET_CONNECTION_ACK:
417 return "CADET_CONNECTION_ACK";
418 case CADET_CONNECTION_READY:
419 return "CADET_CONNECTION_READY";
420 case CADET_CONNECTION_DESTROYED:
421 return "CADET_CONNECTION_DESTROYED";
422 case CADET_CONNECTION_BROKEN:
423 return "CADET_CONNECTION_BROKEN";
426 LOG (GNUNET_ERROR_TYPE_ERROR, " conn state %u unknown!\n", s);
427 return "CADET_CONNECTION_STATE_ERROR";
433 * Initialize a Flow Control structure to the initial state.
435 * @param fc Flow Control structure to initialize.
438 fc_init (struct CadetFlowControl *fc)
440 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
441 fc->last_pid_recv = (uint32_t) -1;
442 fc->last_ack_sent = (uint32_t) 0;
443 fc->last_ack_recv = (uint32_t) 0;
444 fc->poll_task = NULL;
445 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
447 fc->queue_max = (max_msgs_queue / max_connections) + 1;
454 * @param cid Connection ID.
456 static struct CadetConnection *
457 connection_get (const struct GNUNET_CADET_Hash *cid)
459 return GNUNET_CONTAINER_multihashmap_get (connections, GC_h2hc (cid));
464 * Change the connection state. Cannot change a connection marked as destroyed.
466 * @param c Connection to change.
467 * @param state New state to set.
470 connection_change_state (struct CadetConnection* c,
471 enum CadetConnectionState state)
473 LOG (GNUNET_ERROR_TYPE_DEBUG,
474 "Connection %s state %s -> %s\n",
475 GCC_2s (c), GCC_state2s (c->state), GCC_state2s (state));
476 if (CADET_CONNECTION_DESTROYED <= c->state) /* Destroyed or broken. */
478 LOG (GNUNET_ERROR_TYPE_DEBUG, "state not changing anymore\n");
482 if (CADET_CONNECTION_READY == state)
488 * Callback called when a queued ACK message is sent.
490 * @param cls Closure (FC).
491 * @param c Connection this message was on.
492 * @param q Queue handler this call invalidates.
493 * @param type Type of message sent.
494 * @param fwd Was this a FWD going message?
495 * @param size Size of the message.
499 struct CadetConnection *c,
500 struct CadetConnectionQueue *q,
501 uint16_t type, int fwd, size_t size)
503 struct CadetFlowControl *fc = cls;
510 * Send an ACK on the connection, informing the predecessor about
511 * the available buffer space. Should not be called in case the peer
512 * is origin (no predecessor) in the @c fwd direction.
514 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
515 * the ACK itself goes "back" (dest->root).
517 * @param c Connection on which to send the ACK.
518 * @param buffer How much space free to advertise?
519 * @param fwd Is this FWD ACK? (Going dest -> root)
520 * @param force Don't optimize out.
523 send_ack (struct CadetConnection *c, unsigned int buffer, int fwd, int force)
525 struct CadetFlowControl *next_fc;
526 struct CadetFlowControl *prev_fc;
527 struct GNUNET_CADET_ACK msg;
531 /* If origin, there is no connection to send ACKs. Wrong function! */
532 GCC_check_connections ();
533 if (GCC_is_origin (c, fwd))
535 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection %s is origin in %s\n",
536 GCC_2s (c), GC_f2s (fwd));
541 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
542 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
544 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection send %s ack on %s\n",
545 GC_f2s (fwd), GCC_2s (c));
547 /* Check if we need to transmit the ACK. */
548 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
549 if (3 < delta && buffer < delta && GNUNET_NO == force)
551 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
552 LOG (GNUNET_ERROR_TYPE_DEBUG,
553 " last pid recv: %u, last ack sent: %u\n",
554 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
555 GCC_check_connections ();
559 /* Ok, ACK might be necessary, what PID to ACK? */
560 ack = prev_fc->last_pid_recv + buffer;
561 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
562 LOG (GNUNET_ERROR_TYPE_DEBUG,
563 " last pid %u, last ack %u, qmax %u, q %u\n",
564 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
565 next_fc->queue_max, next_fc->queue_n);
566 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
568 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
569 GCC_check_connections ();
573 /* Check if message is already in queue */
574 if (NULL != prev_fc->ack_msg)
576 if (GC_is_pid_bigger (ack, prev_fc->last_ack_sent))
578 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
579 GCC_cancel (prev_fc->ack_msg);
580 /* GCC_cancel triggers ack_sent(), which clears fc->ack_msg */
584 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
585 GCC_check_connections ();
590 prev_fc->last_ack_sent = ack;
592 /* Build ACK message and send on conn */
593 msg.header.size = htons (sizeof (msg));
594 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_ACK);
595 msg.ack = htonl (ack);
598 prev_fc->ack_msg = GCC_send_prebuilt_message (&msg.header, UINT16_MAX, ack,
601 GNUNET_assert (NULL != prev_fc->ack_msg);
602 GCC_check_connections ();
607 * Callback called when a connection queued message is sent.
609 * Calculates the average time and connection packet tracking.
611 * @param cls Closure (ConnectionQueue Handle).
612 * @param c Connection this message was on.
613 * @param sent Was it really sent? (Could have been canceled)
614 * @param type Type of message sent.
615 * @param pid Packet ID, or 0 if not applicable (create, destroy, etc).
616 * @param fwd Was this a FWD going message?
617 * @param size Size of the message.
618 * @param wait Time spent waiting for core (only the time for THIS message)
619 * @return #GNUNET_YES if connection was destroyed, #GNUNET_NO otherwise.
622 conn_message_sent (void *cls,
623 struct CadetConnection *c, int sent,
624 uint16_t type, uint32_t pid, int fwd, size_t size,
625 struct GNUNET_TIME_Relative wait)
627 struct CadetConnectionPerformance *p;
628 struct CadetFlowControl *fc;
629 struct CadetConnectionQueue *q = cls;
633 GCC_check_connections ();
634 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection message_sent\n");
636 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
638 fc = fwd ? &c->fwd_fc : &c->bck_fc;
639 LOG (GNUNET_ERROR_TYPE_DEBUG, " %ssent %s %s pid %u\n",
640 sent ? "" : "not ", GC_f2s (fwd), GC_m2s (type), pid);
646 LOG (GNUNET_ERROR_TYPE_DEBUG, " calling cont\n");
647 q->cont (q->cont_cls, c, q, type, fwd, size);
651 else if (type == GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED
652 || type == GNUNET_MESSAGE_TYPE_CADET_AX)
654 /* If NULL == q and ENCRYPTED == type, message must have been ch_mngmnt */
663 if (type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN
664 && type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY)
666 LOG (GNUNET_ERROR_TYPE_ERROR, "Message %s sent on NULL connection!\n",
669 GCC_check_connections ();
672 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P- %p %u\n", c, c->pending_messages);
673 c->pending_messages--;
674 if ( (GNUNET_YES == c->destroy) &&
675 (0 == c->pending_messages) )
677 LOG (GNUNET_ERROR_TYPE_DEBUG,
678 "! destroying connection!\n");
680 GCC_check_connections ();
683 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
686 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
687 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
688 c->maintenance_q = NULL;
689 /* Don't trigger a keepalive for sent ACKs, only SYN and SYNACKs */
690 if (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE == type || !fwd)
691 schedule_next_keepalive (c, fwd);
694 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
695 case GNUNET_MESSAGE_TYPE_CADET_AX:
696 if (GNUNET_YES == sent)
698 GNUNET_assert (NULL != q);
699 fc->last_pid_sent = pid;
700 if (GC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
701 GCC_start_poll (c, fwd);
702 GCC_send_ack (c, fwd, GNUNET_NO);
703 connection_reset_timeout (c, fwd);
706 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
707 if (GNUNET_NO == forced)
710 LOG (GNUNET_ERROR_TYPE_DEBUG,
711 "! accounting pid %u\n",
716 LOG (GNUNET_ERROR_TYPE_DEBUG,
717 "! forced, Q_N not accounting pid %u\n",
722 case GNUNET_MESSAGE_TYPE_CADET_KX:
723 if (GNUNET_YES == sent)
724 connection_reset_timeout (c, fwd);
727 case GNUNET_MESSAGE_TYPE_CADET_POLL:
731 case GNUNET_MESSAGE_TYPE_CADET_ACK:
735 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
736 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
740 LOG (GNUNET_ERROR_TYPE_ERROR, "%s unknown\n", GC_m2s (type));
744 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
747 return GNUNET_NO; /* Only endpoints are interested in timing. */
750 usecsperbyte = ((double) wait.rel_value_us) / size;
751 if (p->size == AVG_MSGS)
753 /* Array is full. Substract oldest value, add new one and store. */
754 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
755 p->usecsperbyte[p->idx] = usecsperbyte;
756 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
760 /* Array not yet full. Add current value to avg and store. */
761 p->usecsperbyte[p->idx] = usecsperbyte;
763 p->avg += p->usecsperbyte[p->idx];
767 p->idx = (p->idx + 1) % AVG_MSGS;
768 GCC_check_connections ();
774 * Get the previous hop in a connection
776 * @param c Connection.
778 * @return Previous peer in the connection.
780 static struct CadetPeer *
781 get_prev_hop (const struct CadetConnection *c)
787 LOG (GNUNET_ERROR_TYPE_DEBUG,
788 " get prev hop %s [%u/%u]\n",
789 GCC_2s (c), c->own_pos, c->path->length);
790 if (0 == c->own_pos || c->path->length < 2)
791 id = c->path->peers[0];
793 id = c->path->peers[c->own_pos - 1];
795 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
796 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
798 return GCP_get_short (id, GNUNET_YES);
803 * Get the next hop in a connection
805 * @param c Connection.
807 * @return Next peer in the connection.
809 static struct CadetPeer *
810 get_next_hop (const struct CadetConnection *c)
817 LOG (GNUNET_ERROR_TYPE_DEBUG, " get next hop %s [%u/%u]\n",
818 GCC_2s (c), c->own_pos, c->path->length);
819 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
820 id = c->path->peers[c->path->length - 1];
822 id = c->path->peers[c->own_pos + 1];
824 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
825 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
827 return GCP_get_short (id, GNUNET_YES);
832 * Check that the direct neighbours (previous and next hop)
833 * are properly associated with this connection.
835 * @param c connection to check
838 check_neighbours (const struct CadetConnection *c)
841 return; /* nothing to check */
842 GCP_check_connection (get_next_hop (c), c);
843 GCP_check_connection (get_prev_hop (c), c);
848 * Helper for #GCC_check_connections(). Calls #check_neighbours().
852 * @param value the `struct CadetConnection` to check
853 * @return #GNUNET_OK (continue to iterate)
856 check_connection (void *cls,
857 const struct GNUNET_HashCode *key,
860 struct CadetConnection *c = value;
862 check_neighbours (c);
868 * Check invariants for all connections using #check_neighbours().
871 GCC_check_connections ()
873 if (0 == CHECK_INVARIANTS)
875 if (NULL == connections)
877 GNUNET_CONTAINER_multihashmap_iterate (connections,
884 * Get the hop in a connection.
886 * @param c Connection.
887 * @param fwd Next in the FWD direction?
889 * @return Next peer in the connection.
891 static struct CadetPeer *
892 get_hop (struct CadetConnection *c, int fwd)
894 return (fwd) ? get_next_hop (c) : get_prev_hop (c);
899 * Get a bit mask for a message received out-of-order.
901 * @param last_pid_recv Last PID we received prior to the out-of-order.
902 * @param ooo_pid PID of the out-of-order message.
905 get_recv_bitmask (uint32_t last_pid_recv, uint32_t ooo_pid)
907 return 1 << (last_pid_recv - ooo_pid);
912 * Check is an out-of-order message is ok:
913 * - at most 31 messages behind.
916 * @param last_pid_recv Last in-order PID received.
919 is_ooo_ok (uint32_t last_pid_recv, uint32_t ooo_pid, uint32_t ooo_bitmap)
923 if (GC_is_pid_bigger (last_pid_recv - 31, ooo_pid))
926 mask = get_recv_bitmask (last_pid_recv, ooo_pid);
927 if (0 != (ooo_bitmap & mask))
935 * Is traffic coming from this sender 'FWD' traffic?
937 * @param c Connection to check.
938 * @param sender Peer identity of neighbor.
940 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
941 * the traffic is 'FWD'.
942 * #GNUNET_NO for BCK.
943 * #GNUNET_SYSERR for errors.
946 is_fwd (const struct CadetConnection *c,
947 const struct GNUNET_PeerIdentity *sender)
951 id = GNUNET_PEER_search (sender);
952 if (GCP_get_short_id (get_prev_hop (c)) == id)
955 if (GCP_get_short_id (get_next_hop (c)) == id)
959 return GNUNET_SYSERR;
964 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
965 * or a first CONNECTION_ACK directed to us.
967 * @param connection Connection to confirm.
968 * @param fwd Should we send it FWD? (root->dest)
969 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
972 send_connection_ack (struct CadetConnection *connection, int fwd)
974 struct CadetTunnel *t;
975 size_t size = sizeof (struct GNUNET_CADET_ConnectionACK);
977 GCC_check_connections ();
979 LOG (GNUNET_ERROR_TYPE_INFO,
980 "==> { C %s ACK} %19s on conn %s (%p) %s [%5u]\n",
981 GC_f2s (!fwd), "", GCC_2s (connection), connection, GC_f2s (fwd), size);
982 GCP_queue_add (get_hop (connection, fwd), NULL,
983 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK, UINT16_MAX, 0,
984 size, connection, fwd, &conn_message_sent, NULL);
985 connection->pending_messages++;
986 if (CADET_TUNNEL_NEW == GCT_get_cstate (t))
987 GCT_change_cstate (t, CADET_TUNNEL_WAITING);
988 if (CADET_CONNECTION_READY != connection->state)
989 connection_change_state (connection, CADET_CONNECTION_SENT);
990 GCC_check_connections ();
995 * Send a notification that a connection is broken.
997 * @param c Connection that is broken.
998 * @param id1 Peer that has disconnected.
999 * @param id2 Peer that has disconnected.
1000 * @param fwd Direction towards which to send it.
1003 send_broken (struct CadetConnection *c,
1004 const struct GNUNET_PeerIdentity *id1,
1005 const struct GNUNET_PeerIdentity *id2,
1008 struct GNUNET_CADET_ConnectionBroken msg;
1010 GCC_check_connections ();
1011 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1012 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1016 GNUNET_assert (NULL ==
1017 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, 0, c, fwd,
1018 GNUNET_YES, NULL, NULL));
1019 GCC_check_connections ();
1024 * Send a notification that a connection is broken, when a connection
1025 * isn't even known to the local peer or soon to be destroyed.
1027 * @param connection_id Connection ID.
1028 * @param id1 Peer that has disconnected, probably local peer.
1029 * @param id2 Peer that has disconnected can be NULL if unknown.
1030 * @param peer Peer to notify (neighbor who sent the connection).
1033 send_broken_unknown (const struct GNUNET_CADET_Hash *connection_id,
1034 const struct GNUNET_PeerIdentity *id1,
1035 const struct GNUNET_PeerIdentity *id2,
1036 const struct GNUNET_PeerIdentity *peer_id)
1038 struct GNUNET_CADET_ConnectionBroken *msg;
1039 struct CadetPeer *neighbor;
1041 GCC_check_connections ();
1042 LOG (GNUNET_ERROR_TYPE_INFO, "--> BROKEN on unknown connection %s\n",
1043 GNUNET_h2s (GC_h2hc (connection_id)));
1045 msg = GNUNET_new (struct GNUNET_CADET_ConnectionBroken);
1046 msg->header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1047 msg->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1048 msg->cid = *connection_id;
1053 memset (&msg->peer2, 0, sizeof (msg->peer2));
1054 neighbor = GCP_get (peer_id, GNUNET_NO); /* We MUST know neighbor. */
1055 GNUNET_assert (NULL != neighbor);
1056 GCP_queue_add (neighbor, msg, GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN,
1057 UINT16_MAX, 2, sizeof (struct GNUNET_CADET_ConnectionBroken),
1058 NULL, GNUNET_SYSERR, /* connection, fwd */
1059 NULL, NULL); /* continuation */
1060 GCC_check_connections ();
1065 * Send keepalive packets for a connection.
1067 * @param c Connection to keep alive..
1068 * @param fwd Is this a FWD keepalive? (owner -> dest).
1071 send_connection_keepalive (struct CadetConnection *c, int fwd)
1073 struct GNUNET_MessageHeader msg;
1074 struct CadetFlowControl *fc;
1076 GCC_check_connections ();
1077 LOG (GNUNET_ERROR_TYPE_INFO,
1078 "keepalive %s for connection %s\n",
1079 GC_f2s (fwd), GCC_2s (c));
1081 GNUNET_assert (NULL != c->t);
1082 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1083 if (0 < fc->queue_n || GNUNET_YES == GCT_has_queued_traffic (c->t))
1085 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, traffic in queue\n");
1089 GNUNET_STATISTICS_update (stats, "# keepalives sent", 1, GNUNET_NO);
1091 GNUNET_assert (NULL != c->t);
1092 msg.size = htons (sizeof (msg));
1093 msg.type = htons (GNUNET_MESSAGE_TYPE_CADET_KEEPALIVE);
1095 GNUNET_assert (NULL ==
1096 GCT_send_prebuilt_message (&msg, c->t, c,
1097 GNUNET_NO, NULL, NULL));
1098 GCC_check_connections ();
1103 * Send CONNECTION_{CREATE/ACK} packets for a connection.
1105 * @param c Connection for which to send the message.
1106 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
1109 connection_recreate (struct CadetConnection *c, int fwd)
1111 LOG (GNUNET_ERROR_TYPE_DEBUG,
1112 "sending connection recreate\n");
1114 GCC_send_create (c);
1116 send_connection_ack (c, GNUNET_NO);
1121 * Generic connection timer management.
1122 * Depending on the role of the peer in the connection will send the
1123 * appropriate message (build or keepalive)
1125 * @param c Conncetion to maintain.
1126 * @param fwd Is FWD?
1129 connection_maintain (struct CadetConnection *c, int fwd)
1131 if (GNUNET_NO != c->destroy)
1133 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, being destroyed\n");
1140 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1144 if (CADET_TUNNEL_SEARCHING == GCT_get_cstate (c->t))
1146 /* If status is SEARCHING, why is there a connection? Should be WAITING */
1148 GCT_debug (c->t, GNUNET_ERROR_TYPE_ERROR);
1149 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, tunnel SEARCHING\n");
1150 schedule_next_keepalive (c, fwd);
1155 case CADET_CONNECTION_NEW:
1158 case CADET_CONNECTION_SENT:
1159 connection_recreate (c, fwd);
1161 case CADET_CONNECTION_READY:
1162 send_connection_keepalive (c, fwd);
1171 * Keep the connection alive.
1173 * @param c Connection to keep alive.
1174 * @param fwd Direction.
1175 * @param shutdown Are we shutting down? (Don't send traffic)
1176 * Non-zero value for true, not necessarily GNUNET_YES.
1179 connection_keepalive (struct CadetConnection *c, int fwd, int shutdown)
1181 GCC_check_connections ();
1182 LOG (GNUNET_ERROR_TYPE_DEBUG,
1183 "%s keepalive for %s\n",
1184 GC_f2s (fwd), GCC_2s (c));
1187 c->fwd_maintenance_task = NULL;
1189 c->bck_maintenance_task = NULL;
1191 if (GNUNET_NO != shutdown)
1194 connection_maintain (c, fwd);
1195 GCC_check_connections ();
1196 /* Next execution will be scheduled by message_sent or _maintain*/
1201 * Keep the connection alive in the FWD direction.
1203 * @param cls Closure (connection to keepalive).
1204 * @param tc TaskContext.
1207 connection_fwd_keepalive (void *cls,
1208 const struct GNUNET_SCHEDULER_TaskContext *tc)
1210 GCC_check_connections ();
1211 connection_keepalive ((struct CadetConnection *) cls,
1213 tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN);
1214 GCC_check_connections ();
1219 * Keep the connection alive in the BCK direction.
1221 * @param cls Closure (connection to keepalive).
1222 * @param tc TaskContext.
1225 connection_bck_keepalive (void *cls,
1226 const struct GNUNET_SCHEDULER_TaskContext *tc)
1228 GCC_check_connections ();
1229 connection_keepalive ((struct CadetConnection *) cls,
1231 tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN);
1232 GCC_check_connections ();
1237 * Schedule next keepalive task, taking in consideration
1238 * the connection state and number of retries.
1240 * If the peer is not the origin, do nothing.
1242 * @param c Connection for which to schedule the next keepalive.
1243 * @param fwd Direction for the next keepalive.
1246 schedule_next_keepalive (struct CadetConnection *c, int fwd)
1248 struct GNUNET_TIME_Relative delay;
1249 struct GNUNET_SCHEDULER_Task * *task_id;
1250 GNUNET_SCHEDULER_TaskCallback keepalive_task;
1252 GCC_check_connections ();
1253 if (GNUNET_NO == GCC_is_origin (c, fwd))
1256 /* Calculate delay to use, depending on the state of the connection */
1257 if (CADET_CONNECTION_READY == c->state)
1259 delay = refresh_connection_time;
1263 if (1 > c->create_retry)
1264 c->create_retry = 1;
1265 delay = GNUNET_TIME_relative_multiply (create_connection_time,
1267 if (c->create_retry < 64)
1268 c->create_retry *= 2;
1271 /* Select direction-dependent parameters */
1272 if (GNUNET_YES == fwd)
1274 task_id = &c->fwd_maintenance_task;
1275 keepalive_task = &connection_fwd_keepalive;
1279 task_id = &c->bck_maintenance_task;
1280 keepalive_task = &connection_bck_keepalive;
1283 /* Check that no one scheduled it before us */
1284 if (NULL != *task_id)
1286 /* No need for a _break. It can happen for instance when sending a SYNACK
1287 * for a duplicate SYN: the first SYNACK scheduled the task. */
1288 GNUNET_SCHEDULER_cancel (*task_id);
1291 /* Schedule the task */
1292 *task_id = GNUNET_SCHEDULER_add_delayed (delay,
1295 LOG (GNUNET_ERROR_TYPE_DEBUG,
1296 "next keepalive in %s\n",
1297 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1298 GCC_check_connections ();
1303 * @brief Re-initiate traffic on this connection if necessary.
1305 * Check if there is traffic queued towards this peer
1306 * and the core transmit handle is NULL (traffic was stalled).
1307 * If so, call core tmt rdy.
1309 * @param c Connection on which initiate traffic.
1310 * @param fwd Is this about fwd traffic?
1313 connection_unlock_queue (struct CadetConnection *c, int fwd)
1315 struct CadetPeer *peer;
1317 GCC_check_connections ();
1318 LOG (GNUNET_ERROR_TYPE_DEBUG,
1319 "connection_unlock_queue %s on %s\n",
1320 GC_f2s (fwd), GCC_2s (c));
1322 if (GCC_is_terminal (c, fwd))
1324 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal, can unlock!\n");
1328 peer = get_hop (c, fwd);
1329 GCP_queue_unlock (peer, c);
1330 GCC_check_connections ();
1335 * Cancel all transmissions that belong to a certain connection.
1337 * If the connection is scheduled for destruction and no more messages are left,
1338 * the connection will be destroyed by the continuation call.
1340 * @param c Connection which to cancel. Might be destroyed during this call.
1341 * @param fwd Cancel fwd traffic?
1344 connection_cancel_queues (struct CadetConnection *c,
1347 struct CadetFlowControl *fc;
1348 struct CadetPeer *peer;
1350 GCC_check_connections ();
1351 LOG (GNUNET_ERROR_TYPE_DEBUG,
1352 "Cancel %s queues for connection %s\n",
1353 GC_f2s (fwd), GCC_2s (c));
1360 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1361 if (NULL != fc->poll_task)
1363 GNUNET_SCHEDULER_cancel (fc->poll_task);
1364 fc->poll_task = NULL;
1365 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL task for fc %p\n", fc);
1367 if (NULL != fc->poll_msg)
1369 GCC_cancel (fc->poll_msg);
1370 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL msg for fc %p\n", fc);
1372 peer = get_hop (c, fwd);
1373 GCP_queue_cancel (peer, c);
1374 GCC_check_connections ();
1379 * Function called if a connection has been stalled for a while,
1380 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1382 * @param cls Closure (poll ctx).
1383 * @param tc TaskContext.
1386 connection_poll (void *cls,
1387 const struct GNUNET_SCHEDULER_TaskContext *tc);
1391 * Callback called when a queued POLL message is sent.
1393 * @param cls Closure (flow control context).
1394 * @param c Connection this message was on.
1395 * @param q Queue handler this call invalidates.
1396 * @param type Type of message sent.
1397 * @param fwd Was this a FWD going message?
1398 * @param size Size of the message.
1401 poll_sent (void *cls,
1402 struct CadetConnection *c,
1403 struct CadetConnectionQueue *q,
1404 uint16_t type, int fwd, size_t size)
1406 struct CadetFlowControl *fc = cls;
1408 GNUNET_assert (fc->poll_msg == q);
1409 fc->poll_msg = NULL;
1410 if (2 == c->destroy)
1412 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL canceled on shutdown\n");
1415 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL sent for %s, scheduling new one!\n",
1417 GNUNET_assert (NULL == fc->poll_task);
1418 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1419 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1422 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1427 * Function called if a connection has been stalled for a while,
1428 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1430 * @param cls Closure (poll ctx).
1431 * @param tc TaskContext.
1434 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1436 struct CadetFlowControl *fc = cls;
1437 struct GNUNET_CADET_Poll msg;
1438 struct CadetConnection *c;
1441 fc->poll_task = NULL;
1442 GCC_check_connections ();
1443 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1449 fwd = fc == &c->fwd_fc;
1450 LOG (GNUNET_ERROR_TYPE_DEBUG, "Polling connection %s %s\n",
1451 GCC_2s (c), GC_f2s (fwd));
1453 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_POLL);
1454 msg.header.size = htons (sizeof (msg));
1455 msg.pid = htonl (fc->last_pid_sent);
1456 LOG (GNUNET_ERROR_TYPE_DEBUG, " last pid sent: %u\n", fc->last_pid_sent);
1458 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, fc->last_pid_sent, c,
1459 fc == &c->fwd_fc, GNUNET_YES, &poll_sent, fc);
1460 GNUNET_assert (NULL != fc->poll_msg);
1461 GCC_check_connections ();
1466 * Resend all queued messages for a connection on other connections of the
1467 * same tunnel, if possible. The connection WILL BE DESTROYED by this function.
1469 * @param c Connection whose messages to resend.
1470 * @param fwd Resend fwd messages?
1473 resend_messages_and_destroy (struct CadetConnection *c, int fwd)
1475 struct GNUNET_MessageHeader *out_msg;
1476 struct CadetTunnel *t = c->t;
1477 struct CadetPeer *neighbor;
1478 unsigned int pending;
1481 GCC_check_connections ();
1482 c->state = CADET_CONNECTION_DESTROYED;
1483 c->destroy = GNUNET_YES;
1485 destroyed = GNUNET_NO;
1486 neighbor = get_hop (c, fwd);
1487 pending = c->pending_messages;
1489 while (NULL != (out_msg = GCP_connection_pop (neighbor, c, &destroyed)))
1492 GCT_resend_message (out_msg, t);
1493 GNUNET_free (out_msg);
1496 /* All pending messages should have been popped,
1497 * and the connection destroyed by the continuation.
1499 if (GNUNET_YES != destroyed)
1504 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1505 if (NULL != t) GCT_debug (t, GNUNET_ERROR_TYPE_ERROR);
1509 GCC_check_connections ();
1514 * Generic connection timeout implementation.
1516 * Timeout function due to lack of keepalive/traffic from an endpoint.
1517 * Destroys connection if called.
1519 * @param c Connection to destroy.
1520 * @param fwd Was the timeout from the origin? (FWD timeout)
1523 connection_timeout (struct CadetConnection *c, int fwd)
1525 struct CadetFlowControl *reverse_fc;
1527 GCC_check_connections ();
1528 reverse_fc = fwd ? &c->bck_fc : &c->fwd_fc;
1530 LOG (GNUNET_ERROR_TYPE_INFO,
1531 "Connection %s %s timed out. Destroying.\n",
1534 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1536 if (GCC_is_origin (c, fwd)) /* Loopback? Something is wrong! */
1542 /* If dest, salvage queued traffic. */
1543 if (GCC_is_origin (c, !fwd))
1545 const struct GNUNET_PeerIdentity *next_hop;
1547 next_hop = GCP_get_id (fwd ? get_prev_hop (c) : get_next_hop (c));
1548 send_broken_unknown (&c->id, &my_full_id, NULL, next_hop);
1549 if (0 < reverse_fc->queue_n)
1550 resend_messages_and_destroy (c, !fwd);
1551 GCC_check_connections ();
1556 GCC_check_connections ();
1561 * Timeout function due to lack of keepalive/traffic from the owner.
1562 * Destroys connection if called.
1564 * @param cls Closure (connection to destroy).
1565 * @param tc TaskContext.
1568 connection_fwd_timeout (void *cls,
1569 const struct GNUNET_SCHEDULER_TaskContext *tc)
1571 struct CadetConnection *c = cls;
1573 c->fwd_maintenance_task = NULL;
1574 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1576 GCC_check_connections ();
1577 connection_timeout (c, GNUNET_YES);
1578 GCC_check_connections ();
1583 * Timeout function due to lack of keepalive/traffic from the destination.
1584 * Destroys connection if called.
1586 * @param cls Closure (connection to destroy).
1587 * @param tc TaskContext
1590 connection_bck_timeout (void *cls,
1591 const struct GNUNET_SCHEDULER_TaskContext *tc)
1593 struct CadetConnection *c = cls;
1595 c->bck_maintenance_task = NULL;
1596 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1598 GCC_check_connections ();
1599 connection_timeout (c, GNUNET_NO);
1600 GCC_check_connections ();
1605 * Resets the connection timeout task, some other message has done the
1607 * - For the first peer on the direction this means to send
1608 * a keepalive or a path confirmation message (either create or ACK).
1609 * - For all other peers, this means to destroy the connection,
1610 * due to lack of activity.
1611 * Starts the timeout if no timeout was running (connection just created).
1613 * @param c Connection whose timeout to reset.
1614 * @param fwd Is this forward?
1616 * TODO use heap to improve efficiency of scheduler.
1619 connection_reset_timeout (struct CadetConnection *c, int fwd)
1621 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1622 if (GCC_is_origin (c, fwd)) /* Startpoint */
1624 schedule_next_keepalive (c, fwd);
1626 else /* Relay, endpoint. */
1628 struct GNUNET_TIME_Relative delay;
1629 struct GNUNET_SCHEDULER_Task * *ti;
1630 GNUNET_SCHEDULER_TaskCallback f;
1632 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1635 GNUNET_SCHEDULER_cancel (*ti);
1636 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1637 LOG (GNUNET_ERROR_TYPE_DEBUG,
1638 " timing out in %s\n",
1639 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_NO));
1640 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1641 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1647 * Iterator to compare each connection's path with the path of a new connection.
1649 * If the connection conincides, the c member of path is set to the connection
1650 * and the destroy flag of the connection is set.
1652 * @param cls Closure (new path).
1653 * @param c Connection in the tunnel to check.
1656 check_path (void *cls, struct CadetConnection *c)
1658 struct CadetConnection *new_conn = cls;
1659 struct CadetPeerPath *path = new_conn->path;
1661 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking %s (%p), length %u\n",
1662 GCC_2s (c), c, c->path->length);
1665 && c->destroy == GNUNET_NO
1666 && c->state != CADET_CONNECTION_BROKEN
1667 && c->state != CADET_CONNECTION_DESTROYED
1668 && path_equivalent (path, c->path))
1670 new_conn->destroy = GNUNET_YES;
1671 new_conn->path->c = c;
1672 LOG (GNUNET_ERROR_TYPE_DEBUG, " MATCH!\n");
1678 * Finds out if this path is already being used by an existing connection.
1680 * Checks the tunnel towards the destination to see if it contains
1681 * any connection with the same path.
1683 * If the existing connection is ready, it is kept.
1684 * Otherwise if the sender has a smaller ID that ours, we accept it (and
1685 * the peer will eventually reject our attempt).
1687 * @param path Path to check.
1688 * @return #GNUNET_YES if the tunnel has a connection with the same path,
1689 * #GNUNET_NO otherwise.
1692 does_connection_exist (struct CadetConnection *conn)
1694 struct CadetPeer *p;
1695 struct CadetTunnel *t;
1696 struct CadetConnection *c;
1698 p = GCP_get_short (conn->path->peers[0], GNUNET_NO);
1701 t = GCP_get_tunnel (p);
1705 LOG (GNUNET_ERROR_TYPE_DEBUG, "Checking for duplicates\n");
1707 GCT_iterate_connections (t, &check_path, conn);
1709 if (GNUNET_YES == conn->destroy)
1712 conn->destroy = GNUNET_NO;
1713 conn->path->c = conn;
1714 LOG (GNUNET_ERROR_TYPE_DEBUG, " found duplicate of %s\n", GCC_2s (conn));
1715 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate: %s\n", GCC_2s (c));
1716 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1717 if (CADET_CONNECTION_READY == c->state)
1719 /* The other peer confirmed a live connection with this path,
1720 * why is it trying to duplicate it. */
1721 GNUNET_STATISTICS_update (stats, "# duplicate connections", 1, GNUNET_NO);
1724 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate not valid, connection unique\n");
1729 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s has no duplicates\n", GCC_2s (conn));
1736 * @brief Check if the tunnel this connection belongs to has any other
1737 * connection with the same path, and destroy one if so.
1739 * @param cls Closure (connection to check).
1740 * @param tc Task context.
1743 check_duplicates (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1745 struct CadetConnection *c = cls;
1747 c->check_duplicates_task = NULL;
1748 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1751 if (GNUNET_YES == does_connection_exist (c))
1753 GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1754 send_broken (c, &my_full_id, &my_full_id, GCC_is_origin (c, GNUNET_YES));
1762 * Wait for enough time to let any dead connections time out and check for
1763 * any remaining duplicates.
1765 * @param c Connection that is a potential duplicate.
1768 schedule_check_duplicates (struct CadetConnection *c)
1770 struct GNUNET_TIME_Relative delay;
1772 if (NULL != c->check_duplicates_task)
1775 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 5);
1776 c->check_duplicates_task = GNUNET_SCHEDULER_add_delayed (delay,
1784 * Add the connection to the list of both neighbors.
1786 * @param c Connection.
1788 * @return #GNUNET_OK if everything went fine
1789 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1792 register_neighbors (struct CadetConnection *c)
1794 c->next_peer = get_next_hop (c);
1795 c->prev_peer = get_prev_hop (c);
1796 GNUNET_assert (c->next_peer != c->prev_peer);
1797 LOG (GNUNET_ERROR_TYPE_DEBUG,
1798 "register neighbors for connection %s\n",
1800 path_debug (c->path);
1801 LOG (GNUNET_ERROR_TYPE_DEBUG,
1802 "own pos %u\n", c->own_pos);
1803 LOG (GNUNET_ERROR_TYPE_DEBUG,
1804 "putting connection %s to next peer %p\n",
1807 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n",
1809 GCP_2s (c->next_peer));
1810 LOG (GNUNET_ERROR_TYPE_DEBUG,
1811 "putting connection %s to prev peer %p\n",
1814 LOG (GNUNET_ERROR_TYPE_DEBUG,
1815 "prev peer %p %s\n",
1817 GCP_2s (c->prev_peer));
1819 if ( (GNUNET_NO == GCP_is_neighbor (c->next_peer)) ||
1820 (GNUNET_NO == GCP_is_neighbor (c->prev_peer)) )
1822 if (GCC_is_origin (c, GNUNET_YES))
1823 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1824 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1826 LOG (GNUNET_ERROR_TYPE_DEBUG,
1827 " register neighbors failed\n");
1828 LOG (GNUNET_ERROR_TYPE_DEBUG,
1829 " prev: %s, neighbor?: %d\n",
1830 GCP_2s (c->prev_peer),
1831 GCP_is_neighbor (c->prev_peer));
1832 LOG (GNUNET_ERROR_TYPE_DEBUG,
1833 " next: %s, neighbor?: %d\n",
1834 GCP_2s (c->next_peer),
1835 GCP_is_neighbor (c->next_peer));
1836 return GNUNET_SYSERR;
1838 GCP_add_connection (c->next_peer, c, GNUNET_NO);
1839 GCP_add_connection (c->prev_peer, c, GNUNET_YES);
1846 * Remove the connection from the list of both neighbors.
1848 * @param c Connection.
1851 unregister_neighbors (struct CadetConnection *c)
1853 // struct CadetPeer *peer; FIXME dont use next_peer, prev_peer
1854 /* Either already unregistered or never got registered, it's ok either way. */
1855 if (NULL == c->path)
1857 if (NULL != c->next_peer)
1859 GCP_remove_connection (c->next_peer, c);
1860 c->next_peer = NULL;
1862 if (NULL != c->prev_peer)
1864 GCP_remove_connection (c->prev_peer, c);
1865 c->prev_peer = NULL;
1871 * Invalidates all paths towards all peers that comprise the connection which
1872 * rely on the disconnected peer.
1874 * ~O(n^3) (peers in connection * paths/peer * links/path)
1876 * @param c Connection whose peers' paths to clean.
1877 * @param disconnected Peer that disconnected.
1880 invalidate_paths (struct CadetConnection *c, struct CadetPeer *disconnected)
1882 struct CadetPeer *peer;
1885 for (i = 0; i < c->path->length; i++)
1887 peer = GCP_get_short (c->path->peers[i], GNUNET_NO);
1889 GCP_notify_broken_link (peer, &my_full_id, GCP_get_id (disconnected));
1895 * Bind the connection to the peer and the tunnel to that peer.
1897 * If the peer has no tunnel, create one. Update tunnel and connection
1898 * data structres to reflect new status.
1900 * @param c Connection.
1904 add_to_peer (struct CadetConnection *c,
1905 struct CadetPeer *peer)
1907 GCP_add_tunnel (peer);
1908 c->t = GCP_get_tunnel (peer);
1909 GCT_add_connection (c->t, c);
1914 * Log receipt of message on stderr (INFO level).
1916 * @param message Message received.
1917 * @param peer Peer who sent the message.
1918 * @param hash Connection ID.
1921 log_message (const struct GNUNET_MessageHeader *message,
1922 const struct GNUNET_PeerIdentity *peer,
1923 const struct GNUNET_CADET_Hash *hash)
1929 size = ntohs (message->size);
1930 type = ntohs (message->type);
1933 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
1934 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
1935 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
1936 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
1942 LOG (GNUNET_ERROR_TYPE_INFO, "<%s %s on conn %s from %s, %6u bytes\n",
1943 arrow, GC_m2s (type), GNUNET_h2s (GC_h2hc (hash)),
1944 GNUNET_i2s (peer), (unsigned int) size);
1947 /******************************************************************************/
1948 /******************************** API ***********************************/
1949 /******************************************************************************/
1952 * Core handler for connection creation.
1954 * @param cls Closure (unused).
1955 * @param peer Sender (neighbor).
1956 * @param message Message.
1957 * @return #GNUNET_OK to keep the connection open,
1958 * #GNUNET_SYSERR to close it (signal serious error)
1961 GCC_handle_create (void *cls,
1962 const struct GNUNET_PeerIdentity *peer,
1963 const struct GNUNET_MessageHeader *message)
1965 struct GNUNET_CADET_ConnectionCreate *msg;
1966 struct GNUNET_PeerIdentity *id;
1967 struct GNUNET_CADET_Hash *cid;
1968 struct CadetPeerPath *path;
1969 struct CadetPeer *dest_peer;
1970 struct CadetPeer *orig_peer;
1971 struct CadetConnection *c;
1972 unsigned int own_pos;
1975 GCC_check_connections ();
1977 size = ntohs (message->size);
1978 if (size < sizeof (struct GNUNET_CADET_ConnectionCreate))
1980 GNUNET_break_op (0);
1984 /* Calculate hops */
1985 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
1986 if (size % sizeof (struct GNUNET_PeerIdentity))
1988 GNUNET_break_op (0);
1991 if (0 != size % sizeof (struct GNUNET_PeerIdentity))
1993 GNUNET_break_op (0);
1996 size /= sizeof (struct GNUNET_PeerIdentity);
1999 GNUNET_break_op (0);
2002 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
2004 /* Get parameters */
2005 msg = (struct GNUNET_CADET_ConnectionCreate *) message;
2007 log_message (message, peer, cid);
2008 id = (struct GNUNET_PeerIdentity *) &msg[1];
2009 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
2011 /* Create connection */
2012 c = connection_get (cid);
2015 path = path_build_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
2016 size, myid, &own_pos);
2019 /* Path was malformed, probably our own ID was not in it. */
2020 GNUNET_STATISTICS_update (stats, "# malformed paths", 1, GNUNET_NO);
2021 GNUNET_break_op (0);
2027 /* We received this request from a neighbor, we cannot be origin */
2028 GNUNET_STATISTICS_update (stats, "# fake paths", 1, GNUNET_NO);
2029 GNUNET_break_op (0);
2030 path_destroy (path);
2034 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
2035 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
2036 c = GCC_new (cid, NULL, path, own_pos);
2039 if (path->length - 1 == own_pos)
2041 /* If we are destination, why did the creation fail? */
2043 path_destroy (path);
2044 GCC_check_connections ();
2047 send_broken_unknown (cid, &my_full_id,
2048 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
2050 path_destroy (path);
2051 GCC_check_connections ();
2054 GCP_add_path_to_all (path, GNUNET_NO);
2055 connection_reset_timeout (c, GNUNET_YES);
2059 path = path_duplicate (c->path);
2061 if (CADET_CONNECTION_NEW == c->state)
2062 connection_change_state (c, CADET_CONNECTION_SENT);
2064 /* Remember peers */
2065 dest_peer = GCP_get (&id[size - 1], GNUNET_YES);
2066 orig_peer = GCP_get (&id[0], GNUNET_YES);
2068 /* Is it a connection to us? */
2069 if (c->own_pos == path->length - 1)
2071 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
2072 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
2074 add_to_peer (c, orig_peer);
2075 if (GNUNET_YES == does_connection_exist (c))
2077 /* Peer created a connection equal to one we think exists
2079 * Solution: Keep both and postpone disambiguation. In the meantime
2080 * the connection will time out or peer will inform us it is broken.
2083 * - Use explicit duplicate.
2084 * - Accept new conn and destroy the old. (interruption in higher level)
2085 * - Keep the one with higher ID / created by peer with higher ID. */
2086 schedule_check_duplicates (c);
2089 if (CADET_TUNNEL_NEW == GCT_get_cstate (c->t))
2090 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
2092 send_connection_ack (c, GNUNET_NO);
2093 if (CADET_CONNECTION_SENT == c->state)
2094 connection_change_state (c, CADET_CONNECTION_ACK);
2098 /* It's for somebody else! Retransmit. */
2099 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
2100 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
2101 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
2102 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c,
2103 GNUNET_YES, GNUNET_YES,
2106 path_destroy (path);
2107 GCC_check_connections ();
2113 * Core handler for path confirmations.
2115 * @param cls closure
2116 * @param message message
2117 * @param peer peer identity this notification is about
2118 * @return #GNUNET_OK to keep the connection open,
2119 * #GNUNET_SYSERR to close it (signal serious error)
2122 GCC_handle_confirm (void *cls,
2123 const struct GNUNET_PeerIdentity *peer,
2124 const struct GNUNET_MessageHeader *message)
2126 struct GNUNET_CADET_ConnectionACK *msg;
2127 struct CadetConnection *c;
2128 struct CadetPeerPath *p;
2129 struct CadetPeer *pi;
2130 enum CadetConnectionState oldstate;
2133 GCC_check_connections ();
2134 msg = (struct GNUNET_CADET_ConnectionACK *) message;
2135 log_message (message, peer, &msg->cid);
2136 c = connection_get (&msg->cid);
2139 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
2141 LOG (GNUNET_ERROR_TYPE_DEBUG,
2142 " don't know the connection!\n");
2143 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2144 GCC_check_connections ();
2148 if (GNUNET_NO != c->destroy)
2150 GNUNET_assert (CADET_CONNECTION_DESTROYED == c->state);
2151 LOG (GNUNET_ERROR_TYPE_DEBUG,
2152 "connection %s being destroyed, ignoring confirm\n",
2154 GCC_check_connections ();
2158 oldstate = c->state;
2159 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
2160 pi = GCP_get (peer, GNUNET_YES);
2161 if (get_next_hop (c) == pi)
2163 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
2165 if (CADET_CONNECTION_SENT == oldstate)
2166 connection_change_state (c, CADET_CONNECTION_ACK);
2168 else if (get_prev_hop (c) == pi)
2170 LOG (GNUNET_ERROR_TYPE_DEBUG, " FINAL ACK\n");
2172 connection_change_state (c, CADET_CONNECTION_READY);
2176 GNUNET_break_op (0);
2180 connection_reset_timeout (c, fwd);
2182 /* Add path to peers? */
2186 GCP_add_path_to_all (p, GNUNET_YES);
2193 /* Message for us as creator? */
2194 if (GCC_is_origin (c, GNUNET_YES))
2196 if (GNUNET_NO != fwd)
2198 GNUNET_break_op (0);
2201 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
2203 /* If just created, cancel the short timeout and start a long one */
2204 if (CADET_CONNECTION_SENT == oldstate)
2205 connection_reset_timeout (c, GNUNET_YES);
2207 /* Change connection state */
2208 connection_change_state (c, CADET_CONNECTION_READY);
2209 send_connection_ack (c, GNUNET_YES);
2211 /* Change tunnel state, trigger KX */
2212 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2213 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2214 GCC_check_connections ();
2218 /* Message for us as destination? */
2219 if (GCC_is_terminal (c, GNUNET_YES))
2221 if (GNUNET_YES != fwd)
2223 GNUNET_break_op (0);
2226 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
2228 /* If just created, cancel the short timeout and start a long one */
2229 if (CADET_CONNECTION_ACK == oldstate)
2230 connection_reset_timeout (c, GNUNET_NO);
2232 /* Change tunnel state */
2233 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2234 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2235 GCC_check_connections ();
2239 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2240 GNUNET_assert (NULL ==
2241 GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2242 GNUNET_YES, NULL, NULL));
2243 GCC_check_connections ();
2249 * Core handler for notifications of broken connections.
2251 * @param cls Closure (unused).
2252 * @param id Peer identity of sending neighbor.
2253 * @param message Message.
2254 * @return #GNUNET_OK to keep the connection open,
2255 * #GNUNET_SYSERR to close it (signal serious error)
2258 GCC_handle_broken (void* cls,
2259 const struct GNUNET_PeerIdentity* id,
2260 const struct GNUNET_MessageHeader* message)
2262 struct GNUNET_CADET_ConnectionBroken *msg;
2263 struct CadetConnection *c;
2264 struct CadetTunnel *t;
2268 GCC_check_connections ();
2269 msg = (struct GNUNET_CADET_ConnectionBroken *) message;
2270 log_message (message, id, &msg->cid);
2271 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2272 GNUNET_i2s (&msg->peer1));
2273 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2274 GNUNET_i2s (&msg->peer2));
2275 c = connection_get (&msg->cid);
2278 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
2279 GCC_check_connections ();
2285 fwd = is_fwd (c, id);
2286 c->destroy = GNUNET_YES;
2287 if (GCC_is_terminal (c, fwd))
2289 struct CadetPeer *endpoint;
2293 /* A terminal connection should not have 't' set to NULL. */
2295 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
2298 endpoint = GCP_get_short (c->path->peers[c->path->length - 1], GNUNET_YES);
2299 if (2 < c->path->length)
2300 path_invalidate (c->path);
2301 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
2303 c->state = CADET_CONNECTION_BROKEN;
2304 GCT_remove_connection (t, c);
2307 pending = c->pending_messages;
2309 resend_messages_and_destroy (c, !fwd);
2315 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2316 GNUNET_YES, NULL, NULL));
2317 connection_cancel_queues (c, !fwd);
2319 GCC_check_connections ();
2325 * Core handler for tunnel destruction
2327 * @param cls Closure (unused).
2328 * @param peer Peer identity of sending neighbor.
2329 * @param message Message.
2330 * @return #GNUNET_OK to keep the connection open,
2331 * #GNUNET_SYSERR to close it (signal serious error)
2334 GCC_handle_destroy (void *cls,
2335 const struct GNUNET_PeerIdentity *peer,
2336 const struct GNUNET_MessageHeader *message)
2338 const struct GNUNET_CADET_ConnectionDestroy *msg;
2339 struct CadetConnection *c;
2342 GCC_check_connections ();
2343 msg = (const struct GNUNET_CADET_ConnectionDestroy *) message;
2344 log_message (message, peer, &msg->cid);
2345 c = connection_get (&msg->cid);
2348 /* Probably already got the message from another path,
2349 * destroyed the tunnel and retransmitted to children.
2352 GNUNET_STATISTICS_update (stats,
2353 "# control on unknown connection",
2355 LOG (GNUNET_ERROR_TYPE_DEBUG,
2356 " connection unknown: already destroyed?\n");
2357 GCC_check_connections ();
2360 fwd = is_fwd (c, peer);
2361 if (GNUNET_SYSERR == fwd)
2363 GNUNET_break_op (0); /* FIXME */
2366 if (GNUNET_NO == GCC_is_terminal (c, fwd))
2368 GNUNET_assert (NULL ==
2369 GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2370 GNUNET_YES, NULL, NULL));
2372 else if (0 == c->pending_messages)
2374 LOG (GNUNET_ERROR_TYPE_DEBUG, " directly destroying connection!\n");
2376 GCC_check_connections ();
2379 c->destroy = GNUNET_YES;
2380 c->state = CADET_CONNECTION_DESTROYED;
2383 GCT_remove_connection (c->t, c);
2386 GCC_check_connections ();
2392 * Check the message against internal state and test if it goes FWD or BCK.
2394 * Updates the PID, state and timeout values for the connection.
2396 * @param message Message to check. It must belong to an existing connection.
2397 * @param minimum_size The message cannot be smaller than this value.
2398 * @param cid Connection ID (even if @a c is NULL, the ID is still needed).
2399 * @param c Connection this message should belong. If NULL, check fails.
2400 * @param neighbor Neighbor that sent the message.
2403 check_message (const struct GNUNET_MessageHeader *message,
2404 size_t minimum_size,
2405 const struct GNUNET_CADET_Hash* cid,
2406 struct CadetConnection *c,
2407 const struct GNUNET_PeerIdentity *neighbor,
2410 GNUNET_PEER_Id neighbor_id;
2411 struct CadetFlowControl *fc;
2412 struct CadetPeer *hop;
2417 if (ntohs (message->size) < minimum_size)
2419 GNUNET_break_op (0);
2420 LOG (GNUNET_ERROR_TYPE_WARNING, "Size %u < %u\n",
2421 ntohs (message->size), minimum_size);
2422 return GNUNET_SYSERR;
2425 /* Check connection */
2428 GNUNET_STATISTICS_update (stats,
2429 "# unknown connection",
2431 LOG (GNUNET_ERROR_TYPE_DEBUG,
2432 "%s on unknown connection %s\n",
2433 GC_m2s (ntohs (message->type)),
2434 GNUNET_h2s (GC_h2hc (cid)));
2435 send_broken_unknown (cid,
2439 return GNUNET_SYSERR;
2442 /* Check if origin is as expected */
2443 neighbor_id = GNUNET_PEER_search (neighbor);
2444 hop = get_prev_hop (c);
2445 if (neighbor_id == GCP_get_short_id (hop))
2451 hop = get_next_hop (c);
2452 GNUNET_break (hop == c->next_peer);
2453 if (neighbor_id == GCP_get_short_id (hop))
2459 /* Unexpected peer sending traffic on a connection. */
2460 GNUNET_break_op (0);
2461 return GNUNET_SYSERR;
2465 /* Check PID for payload messages */
2466 type = ntohs (message->type);
2467 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type
2468 || GNUNET_MESSAGE_TYPE_CADET_AX == type)
2470 fc = fwd ? &c->bck_fc : &c->fwd_fc;
2471 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u - %u)\n",
2472 pid, fc->last_pid_recv + 1, fc->last_ack_sent);
2473 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
2475 GNUNET_break_op (0);
2476 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
2477 LOG (GNUNET_ERROR_TYPE_WARNING, "Received PID %u, (prev %u), ACK %u\n",
2478 pid, fc->last_pid_recv, fc->last_ack_sent);
2479 return GNUNET_SYSERR;
2481 if (GC_is_pid_bigger (pid, fc->last_pid_recv))
2485 delta = pid - fc->last_pid_recv;
2486 fc->last_pid_recv = pid;
2487 fc->recv_bitmap <<= delta;
2488 fc->recv_bitmap |= 1;
2492 GNUNET_STATISTICS_update (stats, "# out of order PID", 1, GNUNET_NO);
2493 if (GNUNET_NO == is_ooo_ok (fc->last_pid_recv, pid, fc->recv_bitmap))
2495 LOG (GNUNET_ERROR_TYPE_WARNING, "PID %u unexpected (%u+), dropping!\n",
2496 pid, fc->last_pid_recv - 31);
2497 return GNUNET_SYSERR;
2499 fc->recv_bitmap |= get_recv_bitmask (fc->last_pid_recv, pid);
2503 /* Count as connection confirmation. */
2504 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2506 connection_change_state (c, CADET_CONNECTION_READY);
2509 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2510 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2513 connection_reset_timeout (c, fwd);
2520 * Generic handler for cadet network encrypted traffic.
2522 * @param peer Peer identity this notification is about.
2523 * @param msg Encrypted message.
2524 * @return #GNUNET_OK to keep the connection open,
2525 * #GNUNET_SYSERR to close it (signal serious error)
2528 handle_cadet_encrypted (const struct GNUNET_PeerIdentity *peer,
2529 const struct GNUNET_MessageHeader *message)
2531 const struct GNUNET_CADET_Encrypted *otr_msg;
2532 const struct GNUNET_CADET_AX *ax_msg;
2533 const struct GNUNET_CADET_Hash* cid;
2534 struct CadetConnection *c;
2535 size_t minimum_size;
2541 GCC_check_connections ();
2542 if (GNUNET_MESSAGE_TYPE_CADET_AX == ntohs (message->type))
2544 overhead = sizeof (struct GNUNET_CADET_AX);
2545 ax_msg = (const struct GNUNET_CADET_AX *) message;
2547 pid = ntohl (ax_msg->pid);
2552 overhead = sizeof (struct GNUNET_CADET_Encrypted);
2553 otr_msg = (const struct GNUNET_CADET_Encrypted *) message;
2554 cid = &otr_msg->cid;
2555 pid = ntohl (otr_msg->pid);
2558 log_message (message, peer, cid);
2560 minimum_size = sizeof (struct GNUNET_MessageHeader) + overhead;
2561 c = connection_get (cid);
2562 fwd = check_message (message,
2569 /* If something went wrong, discard message. */
2570 if (GNUNET_SYSERR == fwd)
2572 GCC_check_connections ();
2576 /* Is this message for us? */
2577 if (GCC_is_terminal (c, fwd))
2579 GNUNET_STATISTICS_update (stats, "# received encrypted", 1, GNUNET_NO);
2583 GNUNET_break (GNUNET_NO != c->destroy);
2586 GCT_handle_encrypted (c->t, message);
2587 GCC_send_ack (c, fwd, GNUNET_NO);
2588 GCC_check_connections ();
2592 /* Message not for us: forward to next hop */
2593 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2594 if (NULL != otr_msg) /* only otr has ttl */
2596 ttl = ntohl (otr_msg->ttl);
2597 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
2600 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
2601 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
2602 GCC_send_ack (c, fwd, GNUNET_NO);
2603 GCC_check_connections ();
2608 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2609 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2610 GNUNET_NO, NULL, NULL));
2611 GCC_check_connections ();
2617 * Generic handler for cadet network encrypted traffic.
2619 * @param peer Peer identity this notification is about.
2620 * @param msg Encrypted message.
2621 * @return #GNUNET_OK to keep the connection open,
2622 * #GNUNET_SYSERR to close it (signal serious error)
2625 handle_cadet_kx (const struct GNUNET_PeerIdentity *peer,
2626 const struct GNUNET_CADET_KX *msg)
2628 const struct GNUNET_CADET_Hash* cid;
2629 struct CadetConnection *c;
2630 size_t expected_size;
2633 GCC_check_connections ();
2635 log_message (&msg->header, peer, cid);
2637 expected_size = sizeof (struct GNUNET_CADET_KX)
2638 + sizeof (struct GNUNET_MessageHeader);
2639 c = connection_get (cid);
2640 fwd = check_message (&msg->header,
2647 /* If something went wrong, discard message. */
2648 if (GNUNET_SYSERR == fwd)
2651 /* Is this message for us? */
2652 if (GCC_is_terminal (c, fwd))
2654 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2655 GNUNET_STATISTICS_update (stats, "# received KX", 1, GNUNET_NO);
2661 GCT_handle_kx (c->t, &msg[1].header);
2662 GCC_check_connections ();
2666 /* Message not for us: forward to next hop */
2667 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2668 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2669 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2670 GNUNET_NO, NULL, NULL));
2671 GCC_check_connections ();
2677 * Core handler for key exchange traffic (ephemeral key, ping, pong).
2679 * @param cls Closure (unused).
2680 * @param message Message received.
2681 * @param peer Peer who sent the message.
2682 * @return #GNUNET_OK to keep the connection open,
2683 * #GNUNET_SYSERR to close it (signal serious error)
2686 GCC_handle_kx (void *cls,
2687 const struct GNUNET_PeerIdentity *peer,
2688 const struct GNUNET_MessageHeader *message)
2690 GCC_check_connections ();
2691 return handle_cadet_kx (peer, (struct GNUNET_CADET_KX *) message);
2696 * Core handler for encrypted cadet network traffic (channel mgmt, data).
2698 * @param cls Closure (unused).
2699 * @param message Message received.
2700 * @param peer Peer who sent the message.
2701 * @return #GNUNET_OK to keep the connection open,
2702 * #GNUNET_SYSERR to close it (signal serious error)
2705 GCC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
2706 const struct GNUNET_MessageHeader *message)
2708 GCC_check_connections ();
2709 return handle_cadet_encrypted (peer, message);
2714 * Core handler for cadet network traffic point-to-point acks.
2716 * @param cls closure
2717 * @param message message
2718 * @param peer peer identity this notification is about
2719 * @return #GNUNET_OK to keep the connection open,
2720 * #GNUNET_SYSERR to close it (signal serious error)
2723 GCC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
2724 const struct GNUNET_MessageHeader *message)
2726 struct GNUNET_CADET_ACK *msg;
2727 struct CadetConnection *c;
2728 struct CadetFlowControl *fc;
2733 GCC_check_connections ();
2734 msg = (struct GNUNET_CADET_ACK *) message;
2735 log_message (message, peer, &msg->cid);
2736 c = connection_get (&msg->cid);
2739 GNUNET_STATISTICS_update (stats,
2740 "# ack on unknown connection",
2743 send_broken_unknown (&msg->cid,
2747 GCC_check_connections ();
2751 /* Is this a forward or backward ACK? */
2752 id = GNUNET_PEER_search (peer);
2753 if (GCP_get_short_id (get_next_hop (c)) == id)
2758 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2765 GNUNET_break_op (0);
2769 ack = ntohl (msg->ack);
2770 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s ACK %u (was %u)\n",
2771 GC_f2s (fwd), ack, fc->last_ack_recv);
2772 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2773 fc->last_ack_recv = ack;
2775 /* Cancel polling if the ACK is big enough. */
2776 if (NULL != fc->poll_task &&
2777 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2779 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2780 GNUNET_SCHEDULER_cancel (fc->poll_task);
2781 fc->poll_task = NULL;
2782 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2785 connection_unlock_queue (c, fwd);
2786 GCC_check_connections ();
2792 * Core handler for cadet network traffic point-to-point ack polls.
2794 * @param cls closure
2795 * @param message message
2796 * @param peer peer identity this notification is about
2797 * @return #GNUNET_OK to keep the connection open,
2798 * #GNUNET_SYSERR to close it (signal serious error)
2801 GCC_handle_poll (void *cls,
2802 const struct GNUNET_PeerIdentity *peer,
2803 const struct GNUNET_MessageHeader *message)
2805 struct GNUNET_CADET_Poll *msg;
2806 struct CadetConnection *c;
2807 struct CadetFlowControl *fc;
2812 GCC_check_connections ();
2813 msg = (struct GNUNET_CADET_Poll *) message;
2814 log_message (message, peer, &msg->cid);
2815 c = connection_get (&msg->cid);
2818 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2820 LOG (GNUNET_ERROR_TYPE_DEBUG,
2821 "POLL message on unknown connection %s!\n",
2822 GNUNET_h2s (GC_h2hc (&msg->cid)));
2823 send_broken_unknown (&msg->cid,
2827 GCC_check_connections ();
2831 /* Is this a forward or backward ACK?
2832 * Note: a poll should never be needed in a loopback case,
2833 * since there is no possiblility of packet loss there, so
2834 * this way of discerining FWD/BCK should not be a problem.
2836 id = GNUNET_PEER_search (peer);
2837 if (GCP_get_short_id (get_next_hop (c)) == id)
2839 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2842 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2844 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2849 GNUNET_break_op (0);
2853 pid = ntohl (msg->pid);
2854 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2855 fc->last_pid_recv = pid;
2856 fwd = fc == &c->bck_fc;
2857 GCC_send_ack (c, fwd, GNUNET_YES);
2858 GCC_check_connections ();
2865 * Send an ACK on the appropriate connection/channel, depending on
2866 * the direction and the position of the peer.
2868 * @param c Which connection to send the hop-by-hop ACK.
2869 * @param fwd Is this a fwd ACK? (will go dest->root).
2870 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2873 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
2875 unsigned int buffer;
2877 GCC_check_connections ();
2878 LOG (GNUNET_ERROR_TYPE_DEBUG, "GCC send %s ACK on %s\n",
2879 GC_f2s (fwd), GCC_2s (c));
2887 if (GNUNET_NO != c->destroy)
2889 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2890 GCC_check_connections ();
2894 /* Get available buffer space */
2895 if (GCC_is_terminal (c, fwd))
2897 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2898 buffer = GCT_get_channels_buffer (c->t);
2902 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2903 buffer = GCC_get_buffer (c, fwd);
2905 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2906 if (0 == buffer && GNUNET_NO == force)
2908 GCC_check_connections ();
2912 /* Send available buffer space */
2913 if (GCC_is_origin (c, fwd))
2915 GNUNET_assert (NULL != c->t);
2916 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2917 GCT_unchoke_channels (c->t);
2921 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2922 send_ack (c, buffer, fwd, force);
2924 GCC_check_connections ();
2929 * Initialize the connections subsystem
2931 * @param c Configuration handle.
2934 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2936 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2938 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2941 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2942 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2943 GNUNET_SCHEDULER_shutdown ();
2948 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2951 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2952 "CADET", "MAX_CONNECTIONS", "MISSING");
2953 GNUNET_SCHEDULER_shutdown ();
2958 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2959 &refresh_connection_time))
2961 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2962 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2963 GNUNET_SCHEDULER_shutdown ();
2966 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2967 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2972 * Destroy each connection on shutdown.
2974 * @param cls Closure (unused).
2975 * @param key Current key code (CID, unused).
2976 * @param value Value in the hash map (`struct CadetConnection`)
2978 * @return #GNUNET_YES, because we should continue to iterate
2981 shutdown_iterator (void *cls,
2982 const struct GNUNET_HashCode *key,
2985 struct CadetConnection *c = value;
2987 c->state = CADET_CONNECTION_DESTROYED;
2994 * Shut down the connections subsystem.
2999 LOG (GNUNET_ERROR_TYPE_DEBUG, "Shutting down connections\n");
3000 GCC_check_connections ();
3001 GNUNET_CONTAINER_multihashmap_iterate (connections,
3004 GNUNET_CONTAINER_multihashmap_destroy (connections);
3010 * Create a connection.
3012 * @param cid Connection ID (either created locally or imposed remotely).
3013 * @param t Tunnel this connection belongs to (or NULL);
3014 * @param path Path this connection has to use (copy is made).
3015 * @param own_pos Own position in the @c path path.
3017 * @return Newly created connection, NULL in case of error (own id not in path).
3019 struct CadetConnection *
3020 GCC_new (const struct GNUNET_CADET_Hash *cid,
3021 struct CadetTunnel *t,
3022 struct CadetPeerPath *path,
3023 unsigned int own_pos)
3025 struct CadetConnection *c;
3026 struct CadetPeerPath *cpath;
3028 GCC_check_connections ();
3029 cpath = path_duplicate (path);
3030 GNUNET_assert (NULL != cpath);
3031 c = GNUNET_new (struct CadetConnection);
3033 GNUNET_assert (GNUNET_OK ==
3034 GNUNET_CONTAINER_multihashmap_put (connections,
3036 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
3037 fc_init (&c->fwd_fc);
3038 fc_init (&c->bck_fc);
3043 GNUNET_assert (own_pos <= cpath->length - 1);
3044 c->own_pos = own_pos;
3047 if (GNUNET_OK != register_neighbors (c))
3051 /* We were the origin of this request, this means we have invalid
3052 * info about the paths to reach the destination. We must invalidate
3053 * the *original* path to avoid trying it again in the next minute.
3055 if (2 < path->length)
3056 path_invalidate (path);
3060 GCT_debug(t, GNUNET_ERROR_TYPE_WARNING);
3064 path_destroy (c->path);
3069 LOG (GNUNET_ERROR_TYPE_INFO, "New connection %s\n", GCC_2s (c));
3070 GCC_check_connections ();
3076 GCC_destroy (struct CadetConnection *c)
3078 GCC_check_connections ();
3085 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
3086 return; /* -> message_sent -> GCC_destroy. Don't loop. */
3089 LOG (GNUNET_ERROR_TYPE_DEBUG,
3090 "destroying connection %s\n",
3092 LOG (GNUNET_ERROR_TYPE_DEBUG,
3093 " fc's f: %p, b: %p\n",
3094 &c->fwd_fc, &c->bck_fc);
3095 LOG (GNUNET_ERROR_TYPE_DEBUG,
3096 " fc tasks f: %u, b: %u\n",
3097 c->fwd_fc.poll_task,
3098 c->bck_fc.poll_task);
3100 /* Cancel all traffic */
3101 if (NULL != c->path)
3103 connection_cancel_queues (c, GNUNET_YES);
3104 connection_cancel_queues (c, GNUNET_NO);
3106 unregister_neighbors (c);
3107 path_destroy (c->path);
3110 /* Delete from tunnel */
3112 GCT_remove_connection (c->t, c);
3114 if (NULL != c->check_duplicates_task)
3115 GNUNET_SCHEDULER_cancel (c->check_duplicates_task);
3116 if (NULL != c->fwd_maintenance_task)
3117 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
3118 if (NULL != c->bck_maintenance_task)
3119 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
3121 if (GNUNET_NO == c->was_removed)
3123 GNUNET_break (GNUNET_YES ==
3124 GNUNET_CONTAINER_multihashmap_remove (connections,
3128 GNUNET_STATISTICS_update (stats,
3133 GCC_check_connections ();
3138 * Get the connection ID.
3140 * @param c Connection to get the ID from.
3142 * @return ID of the connection.
3144 const struct GNUNET_CADET_Hash *
3145 GCC_get_id (const struct CadetConnection *c)
3152 * Get the connection ID.
3154 * @param c Connection to get the ID from.
3156 * @return ID of the connection.
3158 const struct GNUNET_HashCode *
3159 GCC_get_h (const struct CadetConnection *c)
3161 return GC_h2hc (&c->id);
3166 * Get the connection path.
3168 * @param c Connection to get the path from.
3170 * @return path used by the connection.
3172 const struct CadetPeerPath *
3173 GCC_get_path (const struct CadetConnection *c)
3175 if (GNUNET_NO == c->destroy)
3182 * Get the connection state.
3184 * @param c Connection to get the state from.
3186 * @return state of the connection.
3188 enum CadetConnectionState
3189 GCC_get_state (const struct CadetConnection *c)
3195 * Get the connection tunnel.
3197 * @param c Connection to get the tunnel from.
3199 * @return tunnel of the connection.
3201 struct CadetTunnel *
3202 GCC_get_tunnel (const struct CadetConnection *c)
3209 * Get free buffer space in a connection.
3211 * @param c Connection.
3212 * @param fwd Is query about FWD traffic?
3214 * @return Free buffer space [0 - max_msgs_queue/max_connections]
3217 GCC_get_buffer (struct CadetConnection *c, int fwd)
3219 struct CadetFlowControl *fc;
3221 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3223 LOG (GNUNET_ERROR_TYPE_DEBUG, " Get %s buffer on %s: %u - %u\n",
3224 GC_f2s (fwd), GCC_2s (c), fc->queue_max, fc->queue_n);
3225 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
3227 return (fc->queue_max - fc->queue_n);
3232 * Get how many messages have we allowed to send to us from a direction.
3234 * @param c Connection.
3235 * @param fwd Are we asking about traffic from FWD (BCK messages)?
3237 * @return last_ack_sent - last_pid_recv
3240 GCC_get_allowed (struct CadetConnection *c, int fwd)
3242 struct CadetFlowControl *fc;
3244 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3245 if (CADET_CONNECTION_READY != c->state
3246 || GC_is_pid_bigger (fc->last_pid_recv, fc->last_ack_sent))
3250 return (fc->last_ack_sent - fc->last_pid_recv);
3255 * Get messages queued in a connection.
3257 * @param c Connection.
3258 * @param fwd Is query about FWD traffic?
3260 * @return Number of messages queued.
3263 GCC_get_qn (struct CadetConnection *c, int fwd)
3265 struct CadetFlowControl *fc;
3267 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3274 * Get next PID to use.
3276 * @param c Connection.
3277 * @param fwd Is query about FWD traffic?
3279 * @return Last PID used + 1.
3282 GCC_get_pid (struct CadetConnection *c, int fwd)
3284 struct CadetFlowControl *fc;
3286 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3288 return fc->last_pid_sent + 1;
3293 * Allow the connection to advertise a buffer of the given size.
3295 * The connection will send an @c fwd ACK message (so: in direction !fwd)
3296 * allowing up to last_pid_recv + buffer.
3298 * @param c Connection.
3299 * @param buffer How many more messages the connection can accept.
3300 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
3303 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
3305 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
3306 GCC_2s (c), buffer, GC_f2s (fwd));
3307 send_ack (c, buffer, fwd, GNUNET_NO);
3312 * Notify other peers on a connection of a broken link. Mark connections
3313 * to destroy after all traffic has been sent.
3315 * @param c Connection on which there has been a disconnection.
3316 * @param peer Peer that disconnected.
3319 GCC_neighbor_disconnected (struct CadetConnection *c, struct CadetPeer *peer)
3321 struct CadetPeer *hop;
3325 GCC_check_connections ();
3326 strncpy (peer_name, GCP_2s (peer), 16);
3327 peer_name[15] = '\0';
3328 LOG (GNUNET_ERROR_TYPE_DEBUG,
3329 "shutting down %s, %s disconnected\n",
3330 GCC_2s (c), peer_name);
3332 invalidate_paths (c, peer);
3334 hop = get_prev_hop (c);
3337 /* Path was NULL, we should have deleted the connection. */
3341 fwd = (peer == hop);
3342 if ( (GNUNET_YES == GCC_is_terminal (c, fwd)) ||
3343 (GNUNET_NO != c->destroy) )
3345 /* Local shutdown, or other peer already down (hence 'c->destroy');
3346 so there is no one to notify about this, just clean up. */
3348 GCC_check_connections ();
3351 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
3352 /* Connection will have at least one pending message
3353 * (the one we just scheduled), so delay destruction
3354 * and remove from map so we don't use accidentally. */
3355 c->destroy = GNUNET_YES;
3356 c->state = CADET_CONNECTION_DESTROYED;
3357 GNUNET_assert (GNUNET_NO == c->was_removed);
3358 c->was_removed = GNUNET_YES;
3359 GNUNET_break (GNUNET_YES ==
3360 GNUNET_CONTAINER_multihashmap_remove (connections,
3363 /* Cancel queue in the direction that just died. */
3364 connection_cancel_queues (c, ! fwd);
3365 GCC_stop_poll (c, ! fwd);
3366 unregister_neighbors (c);
3367 GCC_check_connections ();
3372 * Is this peer the first one on the connection?
3374 * @param c Connection.
3375 * @param fwd Is this about fwd traffic?
3377 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
3380 GCC_is_origin (struct CadetConnection *c, int fwd)
3382 if (!fwd && c->path->length - 1 == c->own_pos )
3384 if (fwd && 0 == c->own_pos)
3391 * Is this peer the last one on the connection?
3393 * @param c Connection.
3394 * @param fwd Is this about fwd traffic?
3395 * Note that the ROOT is the terminal for BCK traffic!
3397 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
3400 GCC_is_terminal (struct CadetConnection *c, int fwd)
3402 return GCC_is_origin (c, ! fwd);
3407 * See if we are allowed to send by the next hop in the given direction.
3409 * @param c Connection.
3410 * @param fwd Is this about fwd traffic?
3412 * @return #GNUNET_YES in case it's OK to send.
3415 GCC_is_sendable (struct CadetConnection *c, int fwd)
3417 struct CadetFlowControl *fc;
3419 LOG (GNUNET_ERROR_TYPE_DEBUG,
3420 " checking sendability of %s traffic on %s\n",
3421 GC_f2s (fwd), GCC_2s (c));
3427 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3428 LOG (GNUNET_ERROR_TYPE_DEBUG,
3429 " last ack recv: %u, last pid sent: %u\n",
3430 fc->last_ack_recv, fc->last_pid_sent);
3431 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
3433 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
3436 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
3442 * Check if this connection is a direct one (never trim a direct connection).
3444 * @param c Connection.
3446 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
3449 GCC_is_direct (struct CadetConnection *c)
3451 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
3456 * Sends an already built message on a connection, properly registering
3457 * all used resources.
3459 * @param message Message to send. Function makes a copy of it.
3460 * If message is not hop-by-hop, decrements TTL of copy.
3461 * @param payload_type Type of payload, in case the message is encrypted.
3462 * @param c Connection on which this message is transmitted.
3463 * @param fwd Is this a fwd message?
3464 * @param force Force the connection to accept the message (buffer overfill).
3465 * @param cont Continuation called once message is sent. Can be NULL.
3466 * @param cont_cls Closure for @c cont.
3468 * @return Handle to cancel the message before it's sent.
3469 * NULL on error or if @c cont is NULL.
3470 * Invalid on @c cont call.
3472 struct CadetConnectionQueue *
3473 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
3474 uint16_t payload_type, uint32_t payload_id,
3475 struct CadetConnection *c, int fwd, int force,
3476 GCC_sent cont, void *cont_cls)
3478 struct CadetFlowControl *fc;
3479 struct CadetConnectionQueue *q;
3485 GCC_check_connections ();
3486 size = ntohs (message->size);
3487 data = GNUNET_malloc (size);
3488 memcpy (data, message, size);
3489 type = ntohs (message->type);
3490 LOG (GNUNET_ERROR_TYPE_INFO,
3491 "--> %s (%s %4u) on conn %s (%p) %s [%5u]\n",
3492 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), c,
3495 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3496 droppable = GNUNET_NO == force;
3499 struct GNUNET_CADET_AX *axmsg;
3500 struct GNUNET_CADET_Encrypted *emsg;
3501 struct GNUNET_CADET_KX *kmsg;
3502 struct GNUNET_CADET_ACK *amsg;
3503 struct GNUNET_CADET_Poll *pmsg;
3504 struct GNUNET_CADET_ConnectionDestroy *dmsg;
3505 struct GNUNET_CADET_ConnectionBroken *bmsg;
3508 case GNUNET_MESSAGE_TYPE_CADET_AX:
3509 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
3510 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
3512 emsg = (struct GNUNET_CADET_Encrypted *) data;
3513 ttl = ntohl (emsg->ttl);
3516 GNUNET_break_op (0);
3521 emsg->ttl = htonl (ttl - 1);
3525 axmsg = (struct GNUNET_CADET_AX *) data;
3528 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
3529 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
3530 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
3531 if (GNUNET_YES == droppable)
3537 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
3541 case GNUNET_MESSAGE_TYPE_CADET_KX:
3542 kmsg = (struct GNUNET_CADET_KX *) data;
3546 case GNUNET_MESSAGE_TYPE_CADET_ACK:
3547 amsg = (struct GNUNET_CADET_ACK *) data;
3549 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
3550 droppable = GNUNET_NO;
3553 case GNUNET_MESSAGE_TYPE_CADET_POLL:
3554 pmsg = (struct GNUNET_CADET_Poll *) data;
3556 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL %u\n", ntohl (pmsg->pid));
3557 droppable = GNUNET_NO;
3560 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
3561 dmsg = (struct GNUNET_CADET_ConnectionDestroy *) data;
3565 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
3566 bmsg = (struct GNUNET_CADET_ConnectionBroken *) data;
3570 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
3571 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
3580 if (fc->queue_n > fc->queue_max && droppable)
3582 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
3585 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue full: %u/%u\n",
3586 fc->queue_n, fc->queue_max);
3587 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type
3588 || GNUNET_MESSAGE_TYPE_CADET_AX == type)
3593 return NULL; /* Drop this message */
3596 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %s %u\n",
3597 GCC_2s (c), c->pending_messages);
3598 c->pending_messages++;
3600 q = GNUNET_new (struct CadetConnectionQueue);
3601 q->forced = !droppable;
3602 q->q = GCP_queue_add (get_hop (c, fwd), data, type, payload_type, payload_id,
3603 size, c, fwd, &conn_message_sent, q);
3606 LOG (GNUNET_ERROR_TYPE_DEBUG, "dropping msg on %s, NULL q\n", GCC_2s (c));
3609 GCC_check_connections ();
3613 q->cont_cls = cont_cls;
3614 GCC_check_connections ();
3615 return (NULL == cont) ? NULL : q;
3620 * Cancel a previously sent message while it's in the queue.
3622 * ONLY can be called before the continuation given to the send function
3623 * is called. Once the continuation is called, the message is no longer in the
3626 * @param q Handle to the queue.
3629 GCC_cancel (struct CadetConnectionQueue *q)
3631 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GCC cancel message\n");
3633 /* queue destroy calls message_sent, which calls q->cont and frees q */
3634 GCP_queue_destroy (q->q, GNUNET_YES, GNUNET_NO, 0);
3635 GCC_check_connections ();
3640 * Sends a CREATE CONNECTION message for a path to a peer.
3641 * Changes the connection and tunnel states if necessary.
3643 * @param connection Connection to create.
3646 GCC_send_create (struct CadetConnection *connection)
3648 enum CadetTunnelCState state;
3651 GCC_check_connections ();
3652 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3653 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
3655 LOG (GNUNET_ERROR_TYPE_INFO, "==> %s %19s on conn %s (%p) FWD [%5u]\n",
3656 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE), "",
3657 GCC_2s (connection), connection, size);
3658 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3659 connection, connection->pending_messages);
3660 connection->pending_messages++;
3662 connection->maintenance_q =
3663 GCP_queue_add (get_next_hop (connection), NULL,
3664 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, UINT16_MAX, 0,
3665 size, connection, GNUNET_YES, &conn_message_sent, NULL);
3667 state = GCT_get_cstate (connection->t);
3668 if (CADET_TUNNEL_SEARCHING == state || CADET_TUNNEL_NEW == state)
3669 GCT_change_cstate (connection->t, CADET_TUNNEL_WAITING);
3670 if (CADET_CONNECTION_NEW == connection->state)
3671 connection_change_state (connection, CADET_CONNECTION_SENT);
3672 GCC_check_connections ();
3677 * Send a message to all peers in this connection that the connection
3678 * is no longer valid.
3680 * If some peer should not receive the message, it should be zero'ed out
3681 * before calling this function.
3683 * @param c The connection whose peers to notify.
3686 GCC_send_destroy (struct CadetConnection *c)
3688 struct GNUNET_CADET_ConnectionDestroy msg;
3690 if (GNUNET_YES == c->destroy)
3692 GCC_check_connections ();
3693 msg.header.size = htons (sizeof (msg));
3694 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
3696 LOG (GNUNET_ERROR_TYPE_DEBUG,
3697 " sending connection destroy for connection %s\n",
3700 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3701 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3703 GNUNET_YES, NULL, NULL));
3704 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3705 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3707 GNUNET_YES, NULL, NULL));
3708 c->destroy = GNUNET_YES;
3709 c->state = CADET_CONNECTION_DESTROYED;
3710 GCC_check_connections ();
3715 * @brief Start a polling timer for the connection.
3717 * When a neighbor does not accept more traffic on the connection it could be
3718 * caused by a simple congestion or by a lost ACK. Polling enables to check
3719 * for the lastest ACK status for a connection.
3721 * @param c Connection.
3722 * @param fwd Should we poll in the FWD direction?
3725 GCC_start_poll (struct CadetConnection *c, int fwd)
3727 struct CadetFlowControl *fc;
3729 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3730 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL %s requested\n",
3732 if (NULL != fc->poll_task || NULL != fc->poll_msg)
3734 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL already in progress (t: %p, m: %p)\n",
3735 fc->poll_task, fc->poll_msg);
3738 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL started on request\n");
3739 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
3746 * @brief Stop polling a connection for ACKs.
3748 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3750 * @param c Connection.
3751 * @param fwd Should we stop the poll in the FWD direction?
3754 GCC_stop_poll (struct CadetConnection *c, int fwd)
3756 struct CadetFlowControl *fc;
3758 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3759 if (NULL != fc->poll_task)
3761 GNUNET_SCHEDULER_cancel (fc->poll_task);
3762 fc->poll_task = NULL;
3764 if (NULL != fc->poll_msg)
3766 GCC_cancel (fc->poll_msg);
3767 fc->poll_msg = NULL;
3773 * Get a (static) string for a connection.
3775 * @param c Connection.
3778 GCC_2s (const struct CadetConnection *c)
3785 static char buf[128];
3787 SPRINTF (buf, "%s (->%s)",
3788 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3791 return GNUNET_h2s (GC_h2hc (&c->id));
3796 * Log all possible info about the connection state.
3798 * @param c Connection to debug.
3799 * @param level Debug level to use.
3802 GCC_debug (const struct CadetConnection *c, enum GNUNET_ErrorType level)
3807 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
3809 __FILE__, __FUNCTION__, __LINE__);
3815 LOG2 (level, "CCC DEBUG NULL CONNECTION\n");
3819 LOG2 (level, "CCC DEBUG CONNECTION %s\n", GCC_2s (c));
3820 s = path_2s (c->path);
3821 LOG2 (level, "CCC path %s, own pos: %u\n", s, c->own_pos);
3823 LOG2 (level, "CCC state: %s, destroy: %u\n",
3824 GCC_state2s (c->state), c->destroy);
3825 LOG2 (level, "CCC pending messages: %u\n", c->pending_messages);
3826 if (NULL != c->perf)
3827 LOG2 (level, "CCC us/byte: %f\n", c->perf->avg);
3829 LOG2 (level, "CCC FWD flow control:\n");
3830 LOG2 (level, "CCC queue: %u/%u\n", c->fwd_fc.queue_n, c->fwd_fc.queue_max);
3831 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3832 c->fwd_fc.last_pid_sent, c->fwd_fc.last_pid_recv);
3833 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3834 c->fwd_fc.last_ack_sent, c->fwd_fc.last_ack_recv);
3835 LOG2 (level, "CCC recv PID bitmap: %X\n", c->fwd_fc.recv_bitmap);
3836 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3837 c->fwd_fc.poll_task, c->fwd_fc.poll_msg, c->fwd_fc.ack_msg);
3839 LOG2 (level, "CCC BCK flow control:\n");
3840 LOG2 (level, "CCC queue: %u/%u\n", c->bck_fc.queue_n, c->bck_fc.queue_max);
3841 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3842 c->bck_fc.last_pid_sent, c->bck_fc.last_pid_recv);
3843 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3844 c->bck_fc.last_ack_sent, c->bck_fc.last_ack_recv);
3845 LOG2 (level, "CCC recv PID bitmap: %X\n", c->bck_fc.recv_bitmap);
3846 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3847 c->bck_fc.poll_task, c->bck_fc.poll_msg, c->bck_fc.ack_msg);
3849 LOG2 (level, "CCC DEBUG CONNECTION END\n");