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 #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 (FC).
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 if (2 == c->destroy)
1410 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL canceled on shutdown\n");
1413 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL sent for %s, scheduling new one!\n",
1415 fc->poll_msg = NULL;
1416 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1417 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1420 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1425 * Function called if a connection has been stalled for a while,
1426 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1428 * @param cls Closure (poll ctx).
1429 * @param tc TaskContext.
1432 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1434 struct CadetFlowControl *fc = cls;
1435 struct GNUNET_CADET_Poll msg;
1436 struct CadetConnection *c;
1439 fc->poll_task = NULL;
1440 GCC_check_connections ();
1441 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1447 fwd = fc == &c->fwd_fc;
1448 LOG (GNUNET_ERROR_TYPE_DEBUG, "Polling connection %s %s\n",
1449 GCC_2s (c), GC_f2s (fwd));
1451 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_POLL);
1452 msg.header.size = htons (sizeof (msg));
1453 msg.pid = htonl (fc->last_pid_sent);
1454 LOG (GNUNET_ERROR_TYPE_DEBUG, " last pid sent: %u\n", fc->last_pid_sent);
1456 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, fc->last_pid_sent, c,
1457 fc == &c->fwd_fc, GNUNET_YES, &poll_sent, fc);
1458 GNUNET_assert (NULL != fc->poll_msg);
1459 GCC_check_connections ();
1464 * Resend all queued messages for a connection on other connections of the
1465 * same tunnel, if possible. The connection WILL BE DESTROYED by this function.
1467 * @param c Connection whose messages to resend.
1468 * @param fwd Resend fwd messages?
1471 resend_messages_and_destroy (struct CadetConnection *c, int fwd)
1473 struct GNUNET_MessageHeader *out_msg;
1474 struct CadetTunnel *t = c->t;
1475 struct CadetPeer *neighbor;
1476 unsigned int pending;
1479 GCC_check_connections ();
1480 c->state = CADET_CONNECTION_DESTROYED;
1481 c->destroy = GNUNET_YES;
1483 destroyed = GNUNET_NO;
1484 neighbor = get_hop (c, fwd);
1485 pending = c->pending_messages;
1487 while (NULL != (out_msg = GCP_connection_pop (neighbor, c, &destroyed)))
1490 GCT_resend_message (out_msg, t);
1491 GNUNET_free (out_msg);
1494 /* All pending messages should have been popped,
1495 * and the connection destroyed by the continuation.
1497 if (GNUNET_YES != destroyed)
1502 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1503 if (NULL != t) GCT_debug (t, GNUNET_ERROR_TYPE_ERROR);
1507 GCC_check_connections ();
1512 * Generic connection timeout implementation.
1514 * Timeout function due to lack of keepalive/traffic from an endpoint.
1515 * Destroys connection if called.
1517 * @param c Connection to destroy.
1518 * @param fwd Was the timeout from the origin? (FWD timeout)
1521 connection_timeout (struct CadetConnection *c, int fwd)
1523 struct CadetFlowControl *reverse_fc;
1525 GCC_check_connections ();
1526 reverse_fc = fwd ? &c->bck_fc : &c->fwd_fc;
1528 LOG (GNUNET_ERROR_TYPE_INFO,
1529 "Connection %s %s timed out. Destroying.\n",
1532 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1534 if (GCC_is_origin (c, fwd)) /* Loopback? Something is wrong! */
1540 /* If dest, salvage queued traffic. */
1541 if (GCC_is_origin (c, !fwd))
1543 const struct GNUNET_PeerIdentity *next_hop;
1545 next_hop = GCP_get_id (fwd ? get_prev_hop (c) : get_next_hop (c));
1546 send_broken_unknown (&c->id, &my_full_id, NULL, next_hop);
1547 if (0 < reverse_fc->queue_n)
1548 resend_messages_and_destroy (c, !fwd);
1549 GCC_check_connections ();
1554 GCC_check_connections ();
1559 * Timeout function due to lack of keepalive/traffic from the owner.
1560 * Destroys connection if called.
1562 * @param cls Closure (connection to destroy).
1563 * @param tc TaskContext.
1566 connection_fwd_timeout (void *cls,
1567 const struct GNUNET_SCHEDULER_TaskContext *tc)
1569 struct CadetConnection *c = cls;
1571 c->fwd_maintenance_task = NULL;
1572 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1574 GCC_check_connections ();
1575 connection_timeout (c, GNUNET_YES);
1576 GCC_check_connections ();
1581 * Timeout function due to lack of keepalive/traffic from the destination.
1582 * Destroys connection if called.
1584 * @param cls Closure (connection to destroy).
1585 * @param tc TaskContext
1588 connection_bck_timeout (void *cls,
1589 const struct GNUNET_SCHEDULER_TaskContext *tc)
1591 struct CadetConnection *c = cls;
1593 c->bck_maintenance_task = NULL;
1594 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1596 GCC_check_connections ();
1597 connection_timeout (c, GNUNET_NO);
1598 GCC_check_connections ();
1603 * Resets the connection timeout task, some other message has done the
1605 * - For the first peer on the direction this means to send
1606 * a keepalive or a path confirmation message (either create or ACK).
1607 * - For all other peers, this means to destroy the connection,
1608 * due to lack of activity.
1609 * Starts the timeout if no timeout was running (connection just created).
1611 * @param c Connection whose timeout to reset.
1612 * @param fwd Is this forward?
1614 * TODO use heap to improve efficiency of scheduler.
1617 connection_reset_timeout (struct CadetConnection *c, int fwd)
1619 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1620 if (GCC_is_origin (c, fwd)) /* Startpoint */
1622 schedule_next_keepalive (c, fwd);
1624 else /* Relay, endpoint. */
1626 struct GNUNET_TIME_Relative delay;
1627 struct GNUNET_SCHEDULER_Task * *ti;
1628 GNUNET_SCHEDULER_TaskCallback f;
1630 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1633 GNUNET_SCHEDULER_cancel (*ti);
1634 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1635 LOG (GNUNET_ERROR_TYPE_DEBUG,
1636 " timing out in %s\n",
1637 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_NO));
1638 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1639 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1645 * Iterator to compare each connection's path with the path of a new connection.
1647 * If the connection conincides, the c member of path is set to the connection
1648 * and the destroy flag of the connection is set.
1650 * @param cls Closure (new path).
1651 * @param c Connection in the tunnel to check.
1654 check_path (void *cls, struct CadetConnection *c)
1656 struct CadetConnection *new_conn = cls;
1657 struct CadetPeerPath *path = new_conn->path;
1659 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking %s (%p), length %u\n",
1660 GCC_2s (c), c, c->path->length);
1663 && c->destroy == GNUNET_NO
1664 && c->state != CADET_CONNECTION_BROKEN
1665 && c->state != CADET_CONNECTION_DESTROYED
1666 && path_equivalent (path, c->path))
1668 new_conn->destroy = GNUNET_YES;
1669 new_conn->path->c = c;
1670 LOG (GNUNET_ERROR_TYPE_DEBUG, " MATCH!\n");
1676 * Finds out if this path is already being used by an existing connection.
1678 * Checks the tunnel towards the destination to see if it contains
1679 * any connection with the same path.
1681 * If the existing connection is ready, it is kept.
1682 * Otherwise if the sender has a smaller ID that ours, we accept it (and
1683 * the peer will eventually reject our attempt).
1685 * @param path Path to check.
1686 * @return #GNUNET_YES if the tunnel has a connection with the same path,
1687 * #GNUNET_NO otherwise.
1690 does_connection_exist (struct CadetConnection *conn)
1692 struct CadetPeer *p;
1693 struct CadetTunnel *t;
1694 struct CadetConnection *c;
1696 p = GCP_get_short (conn->path->peers[0], GNUNET_NO);
1699 t = GCP_get_tunnel (p);
1703 LOG (GNUNET_ERROR_TYPE_DEBUG, "Checking for duplicates\n");
1705 GCT_iterate_connections (t, &check_path, conn);
1707 if (GNUNET_YES == conn->destroy)
1710 conn->destroy = GNUNET_NO;
1711 conn->path->c = conn;
1712 LOG (GNUNET_ERROR_TYPE_DEBUG, " found duplicate of %s\n", GCC_2s (conn));
1713 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate: %s\n", GCC_2s (c));
1714 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1715 if (CADET_CONNECTION_READY == c->state)
1717 /* The other peer confirmed a live connection with this path,
1718 * why is it trying to duplicate it. */
1719 GNUNET_STATISTICS_update (stats, "# duplicate connections", 1, GNUNET_NO);
1722 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate not valid, connection unique\n");
1727 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s has no duplicates\n", GCC_2s (conn));
1734 * @brief Check if the tunnel this connection belongs to has any other
1735 * connection with the same path, and destroy one if so.
1737 * @param cls Closure (connection to check).
1738 * @param tc Task context.
1741 check_duplicates (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1743 struct CadetConnection *c = cls;
1745 c->check_duplicates_task = NULL;
1746 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1749 if (GNUNET_YES == does_connection_exist (c))
1751 GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1752 send_broken (c, &my_full_id, &my_full_id, GCC_is_origin (c, GNUNET_YES));
1760 * Wait for enough time to let any dead connections time out and check for
1761 * any remaining duplicates.
1763 * @param c Connection that is a potential duplicate.
1766 schedule_check_duplicates (struct CadetConnection *c)
1768 struct GNUNET_TIME_Relative delay;
1770 if (NULL != c->check_duplicates_task)
1773 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 5);
1774 c->check_duplicates_task = GNUNET_SCHEDULER_add_delayed (delay,
1782 * Add the connection to the list of both neighbors.
1784 * @param c Connection.
1786 * @return #GNUNET_OK if everything went fine
1787 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1790 register_neighbors (struct CadetConnection *c)
1792 c->next_peer = get_next_hop (c);
1793 c->prev_peer = get_prev_hop (c);
1794 GNUNET_assert (c->next_peer != c->prev_peer);
1795 LOG (GNUNET_ERROR_TYPE_DEBUG,
1796 "register neighbors for connection %s\n",
1798 path_debug (c->path);
1799 LOG (GNUNET_ERROR_TYPE_DEBUG,
1800 "own pos %u\n", c->own_pos);
1801 LOG (GNUNET_ERROR_TYPE_DEBUG,
1802 "putting connection %s to next peer %p\n",
1805 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n",
1807 GCP_2s (c->next_peer));
1808 LOG (GNUNET_ERROR_TYPE_DEBUG,
1809 "putting connection %s to prev peer %p\n",
1812 LOG (GNUNET_ERROR_TYPE_DEBUG,
1813 "prev peer %p %s\n",
1815 GCP_2s (c->prev_peer));
1817 if ( (GNUNET_NO == GCP_is_neighbor (c->next_peer)) ||
1818 (GNUNET_NO == GCP_is_neighbor (c->prev_peer)) )
1820 if (GCC_is_origin (c, GNUNET_YES))
1821 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1822 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1824 LOG (GNUNET_ERROR_TYPE_DEBUG,
1825 " register neighbors failed\n");
1826 LOG (GNUNET_ERROR_TYPE_DEBUG,
1827 " prev: %s, neighbor?: %d\n",
1828 GCP_2s (c->prev_peer),
1829 GCP_is_neighbor (c->prev_peer));
1830 LOG (GNUNET_ERROR_TYPE_DEBUG,
1831 " next: %s, neighbor?: %d\n",
1832 GCP_2s (c->next_peer),
1833 GCP_is_neighbor (c->next_peer));
1834 return GNUNET_SYSERR;
1836 GCP_add_connection (c->next_peer, c, GNUNET_NO);
1837 GCP_add_connection (c->prev_peer, c, GNUNET_YES);
1844 * Remove the connection from the list of both neighbors.
1846 * @param c Connection.
1849 unregister_neighbors (struct CadetConnection *c)
1851 // struct CadetPeer *peer; FIXME dont use next_peer, prev_peer
1852 /* Either already unregistered or never got registered, it's ok either way. */
1853 if (NULL == c->path)
1855 if (NULL != c->next_peer)
1857 GCP_remove_connection (c->next_peer, c);
1858 c->next_peer = NULL;
1860 if (NULL != c->prev_peer)
1862 GCP_remove_connection (c->prev_peer, c);
1863 c->prev_peer = NULL;
1869 * Invalidates all paths towards all peers that comprise the connection which
1870 * rely on the disconnected peer.
1872 * ~O(n^3) (peers in connection * paths/peer * links/path)
1874 * @param c Connection whose peers' paths to clean.
1875 * @param disconnected Peer that disconnected.
1878 invalidate_paths (struct CadetConnection *c, struct CadetPeer *disconnected)
1880 struct CadetPeer *peer;
1883 for (i = 0; i < c->path->length; i++)
1885 peer = GCP_get_short (c->path->peers[i], GNUNET_NO);
1887 GCP_notify_broken_link (peer, &my_full_id, GCP_get_id (disconnected));
1893 * Bind the connection to the peer and the tunnel to that peer.
1895 * If the peer has no tunnel, create one. Update tunnel and connection
1896 * data structres to reflect new status.
1898 * @param c Connection.
1902 add_to_peer (struct CadetConnection *c,
1903 struct CadetPeer *peer)
1905 GCP_add_tunnel (peer);
1906 c->t = GCP_get_tunnel (peer);
1907 GCT_add_connection (c->t, c);
1912 * Log receipt of message on stderr (INFO level).
1914 * @param message Message received.
1915 * @param peer Peer who sent the message.
1916 * @param hash Connection ID.
1919 log_message (const struct GNUNET_MessageHeader *message,
1920 const struct GNUNET_PeerIdentity *peer,
1921 const struct GNUNET_CADET_Hash *hash)
1927 size = ntohs (message->size);
1928 type = ntohs (message->type);
1931 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
1932 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
1933 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
1934 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
1940 LOG (GNUNET_ERROR_TYPE_INFO, "<%s %s on conn %s from %s, %6u bytes\n",
1941 arrow, GC_m2s (type), GNUNET_h2s (GC_h2hc (hash)),
1942 GNUNET_i2s (peer), (unsigned int) size);
1945 /******************************************************************************/
1946 /******************************** API ***********************************/
1947 /******************************************************************************/
1950 * Core handler for connection creation.
1952 * @param cls Closure (unused).
1953 * @param peer Sender (neighbor).
1954 * @param message Message.
1955 * @return #GNUNET_OK to keep the connection open,
1956 * #GNUNET_SYSERR to close it (signal serious error)
1959 GCC_handle_create (void *cls,
1960 const struct GNUNET_PeerIdentity *peer,
1961 const struct GNUNET_MessageHeader *message)
1963 struct GNUNET_CADET_ConnectionCreate *msg;
1964 struct GNUNET_PeerIdentity *id;
1965 struct GNUNET_CADET_Hash *cid;
1966 struct CadetPeerPath *path;
1967 struct CadetPeer *dest_peer;
1968 struct CadetPeer *orig_peer;
1969 struct CadetConnection *c;
1970 unsigned int own_pos;
1973 GCC_check_connections ();
1975 size = ntohs (message->size);
1976 if (size < sizeof (struct GNUNET_CADET_ConnectionCreate))
1978 GNUNET_break_op (0);
1982 /* Calculate hops */
1983 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
1984 if (size % sizeof (struct GNUNET_PeerIdentity))
1986 GNUNET_break_op (0);
1989 if (0 != size % sizeof (struct GNUNET_PeerIdentity))
1991 GNUNET_break_op (0);
1994 size /= sizeof (struct GNUNET_PeerIdentity);
1997 GNUNET_break_op (0);
2000 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
2002 /* Get parameters */
2003 msg = (struct GNUNET_CADET_ConnectionCreate *) message;
2005 log_message (message, peer, cid);
2006 id = (struct GNUNET_PeerIdentity *) &msg[1];
2007 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
2009 /* Create connection */
2010 c = connection_get (cid);
2013 path = path_build_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
2014 size, myid, &own_pos);
2017 /* Path was malformed, probably our own ID was not in it. */
2018 GNUNET_STATISTICS_update (stats, "# malformed paths", 1, GNUNET_NO);
2019 GNUNET_break_op (0);
2025 /* We received this request from a neighbor, we cannot be origin */
2026 GNUNET_STATISTICS_update (stats, "# fake paths", 1, GNUNET_NO);
2027 GNUNET_break_op (0);
2028 path_destroy (path);
2032 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
2033 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
2034 c = GCC_new (cid, NULL, path, own_pos);
2037 if (path->length - 1 == own_pos)
2039 /* If we are destination, why did the creation fail? */
2041 path_destroy (path);
2042 GCC_check_connections ();
2045 send_broken_unknown (cid, &my_full_id,
2046 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
2048 path_destroy (path);
2049 GCC_check_connections ();
2052 GCP_add_path_to_all (path, GNUNET_NO);
2053 connection_reset_timeout (c, GNUNET_YES);
2057 path = path_duplicate (c->path);
2059 if (CADET_CONNECTION_NEW == c->state)
2060 connection_change_state (c, CADET_CONNECTION_SENT);
2062 /* Remember peers */
2063 dest_peer = GCP_get (&id[size - 1], GNUNET_YES);
2064 orig_peer = GCP_get (&id[0], GNUNET_YES);
2066 /* Is it a connection to us? */
2067 if (c->own_pos == path->length - 1)
2069 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
2070 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
2072 add_to_peer (c, orig_peer);
2073 if (GNUNET_YES == does_connection_exist (c))
2075 /* Peer created a connection equal to one we think exists
2077 * Solution: Keep both and postpone disambiguation. In the meantime
2078 * the connection will time out or peer will inform us it is broken.
2081 * - Use explicit duplicate.
2082 * - Accept new conn and destroy the old. (interruption in higher level)
2083 * - Keep the one with higher ID / created by peer with higher ID. */
2084 schedule_check_duplicates (c);
2087 if (CADET_TUNNEL_NEW == GCT_get_cstate (c->t))
2088 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
2090 send_connection_ack (c, GNUNET_NO);
2091 if (CADET_CONNECTION_SENT == c->state)
2092 connection_change_state (c, CADET_CONNECTION_ACK);
2096 /* It's for somebody else! Retransmit. */
2097 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
2098 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
2099 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
2100 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c,
2101 GNUNET_YES, GNUNET_YES,
2104 path_destroy (path);
2105 GCC_check_connections ();
2111 * Core handler for path confirmations.
2113 * @param cls closure
2114 * @param message message
2115 * @param peer peer identity this notification is about
2116 * @return #GNUNET_OK to keep the connection open,
2117 * #GNUNET_SYSERR to close it (signal serious error)
2120 GCC_handle_confirm (void *cls,
2121 const struct GNUNET_PeerIdentity *peer,
2122 const struct GNUNET_MessageHeader *message)
2124 struct GNUNET_CADET_ConnectionACK *msg;
2125 struct CadetConnection *c;
2126 struct CadetPeerPath *p;
2127 struct CadetPeer *pi;
2128 enum CadetConnectionState oldstate;
2131 GCC_check_connections ();
2132 msg = (struct GNUNET_CADET_ConnectionACK *) message;
2133 log_message (message, peer, &msg->cid);
2134 c = connection_get (&msg->cid);
2137 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
2139 LOG (GNUNET_ERROR_TYPE_DEBUG,
2140 " don't know the connection!\n");
2141 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2142 GCC_check_connections ();
2146 if (GNUNET_NO != c->destroy)
2148 GNUNET_assert (CADET_CONNECTION_DESTROYED != c->state);
2149 LOG (GNUNET_ERROR_TYPE_DEBUG,
2150 "connection %s being destroyed, ignoring confirm\n",
2152 GCC_check_connections ();
2156 oldstate = c->state;
2157 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
2158 pi = GCP_get (peer, GNUNET_YES);
2159 if (get_next_hop (c) == pi)
2161 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
2163 if (CADET_CONNECTION_SENT == oldstate)
2164 connection_change_state (c, CADET_CONNECTION_ACK);
2166 else if (get_prev_hop (c) == pi)
2168 LOG (GNUNET_ERROR_TYPE_DEBUG, " FINAL ACK\n");
2170 connection_change_state (c, CADET_CONNECTION_READY);
2174 GNUNET_break_op (0);
2178 connection_reset_timeout (c, fwd);
2180 /* Add path to peers? */
2184 GCP_add_path_to_all (p, GNUNET_YES);
2191 /* Message for us as creator? */
2192 if (GCC_is_origin (c, GNUNET_YES))
2194 if (GNUNET_NO != fwd)
2196 GNUNET_break_op (0);
2199 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
2201 /* If just created, cancel the short timeout and start a long one */
2202 if (CADET_CONNECTION_SENT == oldstate)
2203 connection_reset_timeout (c, GNUNET_YES);
2205 /* Change connection state */
2206 connection_change_state (c, CADET_CONNECTION_READY);
2207 send_connection_ack (c, GNUNET_YES);
2209 /* Change tunnel state, trigger KX */
2210 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2211 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2212 GCC_check_connections ();
2216 /* Message for us as destination? */
2217 if (GCC_is_terminal (c, GNUNET_YES))
2219 if (GNUNET_YES != fwd)
2221 GNUNET_break_op (0);
2224 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
2226 /* If just created, cancel the short timeout and start a long one */
2227 if (CADET_CONNECTION_ACK == oldstate)
2228 connection_reset_timeout (c, GNUNET_NO);
2230 /* Change tunnel state */
2231 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2232 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2233 GCC_check_connections ();
2237 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2238 GNUNET_assert (NULL ==
2239 GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2240 GNUNET_YES, NULL, NULL));
2241 GCC_check_connections ();
2247 * Core handler for notifications of broken connections.
2249 * @param cls Closure (unused).
2250 * @param id Peer identity of sending neighbor.
2251 * @param message Message.
2252 * @return #GNUNET_OK to keep the connection open,
2253 * #GNUNET_SYSERR to close it (signal serious error)
2256 GCC_handle_broken (void* cls,
2257 const struct GNUNET_PeerIdentity* id,
2258 const struct GNUNET_MessageHeader* message)
2260 struct GNUNET_CADET_ConnectionBroken *msg;
2261 struct CadetConnection *c;
2262 struct CadetTunnel *t;
2266 GCC_check_connections ();
2267 msg = (struct GNUNET_CADET_ConnectionBroken *) message;
2268 log_message (message, id, &msg->cid);
2269 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2270 GNUNET_i2s (&msg->peer1));
2271 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2272 GNUNET_i2s (&msg->peer2));
2273 c = connection_get (&msg->cid);
2276 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
2277 GCC_check_connections ();
2283 fwd = is_fwd (c, id);
2284 c->destroy = GNUNET_YES;
2285 if (GCC_is_terminal (c, fwd))
2287 struct CadetPeer *endpoint;
2291 /* A terminal connection should not have 't' set to NULL. */
2293 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
2296 endpoint = GCP_get_short (c->path->peers[c->path->length - 1], GNUNET_YES);
2297 if (2 < c->path->length)
2298 path_invalidate (c->path);
2299 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
2301 c->state = CADET_CONNECTION_BROKEN;
2302 GCT_remove_connection (t, c);
2305 pending = c->pending_messages;
2307 resend_messages_and_destroy (c, !fwd);
2313 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2314 GNUNET_YES, NULL, NULL));
2315 connection_cancel_queues (c, !fwd);
2317 GCC_check_connections ();
2323 * Core handler for tunnel destruction
2325 * @param cls Closure (unused).
2326 * @param peer Peer identity of sending neighbor.
2327 * @param message Message.
2328 * @return #GNUNET_OK to keep the connection open,
2329 * #GNUNET_SYSERR to close it (signal serious error)
2332 GCC_handle_destroy (void *cls,
2333 const struct GNUNET_PeerIdentity *peer,
2334 const struct GNUNET_MessageHeader *message)
2336 const struct GNUNET_CADET_ConnectionDestroy *msg;
2337 struct CadetConnection *c;
2340 GCC_check_connections ();
2341 msg = (const struct GNUNET_CADET_ConnectionDestroy *) message;
2342 log_message (message, peer, &msg->cid);
2343 c = connection_get (&msg->cid);
2346 /* Probably already got the message from another path,
2347 * destroyed the tunnel and retransmitted to children.
2350 GNUNET_STATISTICS_update (stats,
2351 "# control on unknown connection",
2353 LOG (GNUNET_ERROR_TYPE_DEBUG,
2354 " connection unknown: already destroyed?\n");
2355 GCC_check_connections ();
2358 fwd = is_fwd (c, peer);
2359 if (GNUNET_SYSERR == fwd)
2361 GNUNET_break_op (0); /* FIXME */
2364 if (GNUNET_NO == GCC_is_terminal (c, fwd))
2366 GNUNET_assert (NULL ==
2367 GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2368 GNUNET_YES, NULL, NULL));
2370 else if (0 == c->pending_messages)
2372 LOG (GNUNET_ERROR_TYPE_DEBUG, " directly destroying connection!\n");
2374 GCC_check_connections ();
2377 c->destroy = GNUNET_YES;
2378 c->state = CADET_CONNECTION_DESTROYED;
2381 GCT_remove_connection (c->t, c);
2384 GCC_check_connections ();
2390 * Check the message against internal state and test if it goes FWD or BCK.
2392 * Updates the PID, state and timeout values for the connection.
2394 * @param message Message to check. It must belong to an existing connection.
2395 * @param minimum_size The message cannot be smaller than this value.
2396 * @param cid Connection ID (even if @a c is NULL, the ID is still needed).
2397 * @param c Connection this message should belong. If NULL, check fails.
2398 * @param neighbor Neighbor that sent the message.
2401 check_message (const struct GNUNET_MessageHeader *message,
2402 size_t minimum_size,
2403 const struct GNUNET_CADET_Hash* cid,
2404 struct CadetConnection *c,
2405 const struct GNUNET_PeerIdentity *neighbor,
2408 GNUNET_PEER_Id neighbor_id;
2409 struct CadetFlowControl *fc;
2410 struct CadetPeer *hop;
2415 if (ntohs (message->size) < minimum_size)
2417 GNUNET_break_op (0);
2418 LOG (GNUNET_ERROR_TYPE_WARNING, "Size %u < %u\n",
2419 ntohs (message->size), minimum_size);
2420 return GNUNET_SYSERR;
2423 /* Check connection */
2426 GNUNET_STATISTICS_update (stats,
2427 "# unknown connection",
2429 LOG (GNUNET_ERROR_TYPE_DEBUG,
2430 "%s on unknown connection %s\n",
2431 GC_m2s (ntohs (message->type)),
2432 GNUNET_h2s (GC_h2hc (cid)));
2433 send_broken_unknown (cid,
2437 return GNUNET_SYSERR;
2440 /* Check if origin is as expected */
2441 neighbor_id = GNUNET_PEER_search (neighbor);
2442 hop = get_prev_hop (c);
2443 if (neighbor_id == GCP_get_short_id (hop))
2449 hop = get_next_hop (c);
2450 GNUNET_break (hop == c->next_peer);
2451 if (neighbor_id == GCP_get_short_id (hop))
2457 /* Unexpected peer sending traffic on a connection. */
2458 GNUNET_break_op (0);
2459 return GNUNET_SYSERR;
2463 /* Check PID for payload messages */
2464 type = ntohs (message->type);
2465 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type
2466 || GNUNET_MESSAGE_TYPE_CADET_AX == type)
2468 fc = fwd ? &c->bck_fc : &c->fwd_fc;
2469 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u - %u)\n",
2470 pid, fc->last_pid_recv + 1, fc->last_ack_sent);
2471 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
2473 GNUNET_break_op (0);
2474 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
2475 LOG (GNUNET_ERROR_TYPE_WARNING, "Received PID %u, (prev %u), ACK %u\n",
2476 pid, fc->last_pid_recv, fc->last_ack_sent);
2477 return GNUNET_SYSERR;
2479 if (GC_is_pid_bigger (pid, fc->last_pid_recv))
2483 delta = pid - fc->last_pid_recv;
2484 fc->last_pid_recv = pid;
2485 fc->recv_bitmap <<= delta;
2486 fc->recv_bitmap |= 1;
2490 GNUNET_STATISTICS_update (stats, "# out of order PID", 1, GNUNET_NO);
2491 if (GNUNET_NO == is_ooo_ok (fc->last_pid_recv, pid, fc->recv_bitmap))
2493 LOG (GNUNET_ERROR_TYPE_WARNING, "PID %u unexpected (%u+), dropping!\n",
2494 pid, fc->last_pid_recv - 31);
2495 return GNUNET_SYSERR;
2497 fc->recv_bitmap |= get_recv_bitmask (fc->last_pid_recv, pid);
2501 /* Count as connection confirmation. */
2502 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2504 connection_change_state (c, CADET_CONNECTION_READY);
2507 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2508 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2511 connection_reset_timeout (c, fwd);
2518 * Generic handler for cadet network encrypted traffic.
2520 * @param peer Peer identity this notification is about.
2521 * @param msg Encrypted message.
2522 * @return #GNUNET_OK to keep the connection open,
2523 * #GNUNET_SYSERR to close it (signal serious error)
2526 handle_cadet_encrypted (const struct GNUNET_PeerIdentity *peer,
2527 const struct GNUNET_MessageHeader *message)
2529 const struct GNUNET_CADET_Encrypted *otr_msg;
2530 const struct GNUNET_CADET_AX *ax_msg;
2531 const struct GNUNET_CADET_Hash* cid;
2532 struct CadetConnection *c;
2533 size_t minimum_size;
2539 GCC_check_connections ();
2540 if (GNUNET_MESSAGE_TYPE_CADET_AX == ntohs (message->type))
2542 overhead = sizeof (struct GNUNET_CADET_AX);
2543 ax_msg = (const struct GNUNET_CADET_AX *) message;
2545 pid = ntohl (ax_msg->pid);
2550 overhead = sizeof (struct GNUNET_CADET_Encrypted);
2551 otr_msg = (const struct GNUNET_CADET_Encrypted *) message;
2552 cid = &otr_msg->cid;
2553 pid = ntohl (otr_msg->pid);
2556 log_message (message, peer, cid);
2558 minimum_size = sizeof (struct GNUNET_MessageHeader) + overhead;
2559 c = connection_get (cid);
2560 fwd = check_message (message,
2567 /* If something went wrong, discard message. */
2568 if (GNUNET_SYSERR == fwd)
2570 GCC_check_connections ();
2574 /* Is this message for us? */
2575 if (GCC_is_terminal (c, fwd))
2577 GNUNET_STATISTICS_update (stats, "# received encrypted", 1, GNUNET_NO);
2581 GNUNET_break (GNUNET_NO != c->destroy);
2584 GCT_handle_encrypted (c->t, message);
2585 GCC_send_ack (c, fwd, GNUNET_NO);
2586 GCC_check_connections ();
2590 /* Message not for us: forward to next hop */
2591 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2592 if (NULL != otr_msg) /* only otr has ttl */
2594 ttl = ntohl (otr_msg->ttl);
2595 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
2598 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
2599 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
2600 GCC_send_ack (c, fwd, GNUNET_NO);
2601 GCC_check_connections ();
2606 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2607 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2608 GNUNET_NO, NULL, NULL));
2609 GCC_check_connections ();
2615 * Generic handler for cadet network encrypted traffic.
2617 * @param peer Peer identity this notification is about.
2618 * @param msg Encrypted message.
2619 * @return #GNUNET_OK to keep the connection open,
2620 * #GNUNET_SYSERR to close it (signal serious error)
2623 handle_cadet_kx (const struct GNUNET_PeerIdentity *peer,
2624 const struct GNUNET_CADET_KX *msg)
2626 const struct GNUNET_CADET_Hash* cid;
2627 struct CadetConnection *c;
2628 size_t expected_size;
2631 GCC_check_connections ();
2633 log_message (&msg->header, peer, cid);
2635 expected_size = sizeof (struct GNUNET_CADET_KX)
2636 + sizeof (struct GNUNET_MessageHeader);
2637 c = connection_get (cid);
2638 fwd = check_message (&msg->header,
2645 /* If something went wrong, discard message. */
2646 if (GNUNET_SYSERR == fwd)
2649 /* Is this message for us? */
2650 if (GCC_is_terminal (c, fwd))
2652 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2653 GNUNET_STATISTICS_update (stats, "# received KX", 1, GNUNET_NO);
2659 GCT_handle_kx (c->t, &msg[1].header);
2660 GCC_check_connections ();
2664 /* Message not for us: forward to next hop */
2665 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2666 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2667 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2668 GNUNET_NO, NULL, NULL));
2669 GCC_check_connections ();
2675 * Core handler for key exchange traffic (ephemeral key, ping, pong).
2677 * @param cls Closure (unused).
2678 * @param message Message received.
2679 * @param peer Peer who sent the message.
2680 * @return #GNUNET_OK to keep the connection open,
2681 * #GNUNET_SYSERR to close it (signal serious error)
2684 GCC_handle_kx (void *cls,
2685 const struct GNUNET_PeerIdentity *peer,
2686 const struct GNUNET_MessageHeader *message)
2688 GCC_check_connections ();
2689 return handle_cadet_kx (peer, (struct GNUNET_CADET_KX *) message);
2694 * Core handler for encrypted cadet network traffic (channel mgmt, data).
2696 * @param cls Closure (unused).
2697 * @param message Message received.
2698 * @param peer Peer who sent the message.
2699 * @return #GNUNET_OK to keep the connection open,
2700 * #GNUNET_SYSERR to close it (signal serious error)
2703 GCC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
2704 const struct GNUNET_MessageHeader *message)
2706 GCC_check_connections ();
2707 return handle_cadet_encrypted (peer, message);
2712 * Core handler for cadet network traffic point-to-point acks.
2714 * @param cls closure
2715 * @param message message
2716 * @param peer peer identity this notification is about
2717 * @return #GNUNET_OK to keep the connection open,
2718 * #GNUNET_SYSERR to close it (signal serious error)
2721 GCC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
2722 const struct GNUNET_MessageHeader *message)
2724 struct GNUNET_CADET_ACK *msg;
2725 struct CadetConnection *c;
2726 struct CadetFlowControl *fc;
2731 GCC_check_connections ();
2732 msg = (struct GNUNET_CADET_ACK *) message;
2733 log_message (message, peer, &msg->cid);
2734 c = connection_get (&msg->cid);
2737 GNUNET_STATISTICS_update (stats,
2738 "# ack on unknown connection",
2741 send_broken_unknown (&msg->cid,
2745 GCC_check_connections ();
2749 /* Is this a forward or backward ACK? */
2750 id = GNUNET_PEER_search (peer);
2751 if (GCP_get_short_id (get_next_hop (c)) == id)
2756 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2763 GNUNET_break_op (0);
2767 ack = ntohl (msg->ack);
2768 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s ACK %u (was %u)\n",
2769 GC_f2s (fwd), ack, fc->last_ack_recv);
2770 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2771 fc->last_ack_recv = ack;
2773 /* Cancel polling if the ACK is big enough. */
2774 if (NULL != fc->poll_task &&
2775 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2777 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2778 GNUNET_SCHEDULER_cancel (fc->poll_task);
2779 fc->poll_task = NULL;
2780 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2783 connection_unlock_queue (c, fwd);
2784 GCC_check_connections ();
2790 * Core handler for cadet network traffic point-to-point ack polls.
2792 * @param cls closure
2793 * @param message message
2794 * @param peer peer identity this notification is about
2795 * @return #GNUNET_OK to keep the connection open,
2796 * #GNUNET_SYSERR to close it (signal serious error)
2799 GCC_handle_poll (void *cls,
2800 const struct GNUNET_PeerIdentity *peer,
2801 const struct GNUNET_MessageHeader *message)
2803 struct GNUNET_CADET_Poll *msg;
2804 struct CadetConnection *c;
2805 struct CadetFlowControl *fc;
2810 GCC_check_connections ();
2811 msg = (struct GNUNET_CADET_Poll *) message;
2812 log_message (message, peer, &msg->cid);
2813 c = connection_get (&msg->cid);
2816 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2818 LOG (GNUNET_ERROR_TYPE_DEBUG,
2819 "POLL message on unknown connection %s!\n",
2820 GNUNET_h2s (GC_h2hc (&msg->cid)));
2821 send_broken_unknown (&msg->cid,
2825 GCC_check_connections ();
2829 /* Is this a forward or backward ACK?
2830 * Note: a poll should never be needed in a loopback case,
2831 * since there is no possiblility of packet loss there, so
2832 * this way of discerining FWD/BCK should not be a problem.
2834 id = GNUNET_PEER_search (peer);
2835 if (GCP_get_short_id (get_next_hop (c)) == id)
2837 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2840 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2842 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2847 GNUNET_break_op (0);
2851 pid = ntohl (msg->pid);
2852 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2853 fc->last_pid_recv = pid;
2854 fwd = fc == &c->bck_fc;
2855 GCC_send_ack (c, fwd, GNUNET_YES);
2856 GCC_check_connections ();
2863 * Send an ACK on the appropriate connection/channel, depending on
2864 * the direction and the position of the peer.
2866 * @param c Which connection to send the hop-by-hop ACK.
2867 * @param fwd Is this a fwd ACK? (will go dest->root).
2868 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2871 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
2873 unsigned int buffer;
2875 GCC_check_connections ();
2876 LOG (GNUNET_ERROR_TYPE_DEBUG, "GCC send %s ACK on %s\n",
2877 GC_f2s (fwd), GCC_2s (c));
2885 if (GNUNET_NO != c->destroy)
2887 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2888 GCC_check_connections ();
2892 /* Get available buffer space */
2893 if (GCC_is_terminal (c, fwd))
2895 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2896 buffer = GCT_get_channels_buffer (c->t);
2900 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2901 buffer = GCC_get_buffer (c, fwd);
2903 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2904 if (0 == buffer && GNUNET_NO == force)
2906 GCC_check_connections ();
2910 /* Send available buffer space */
2911 if (GCC_is_origin (c, fwd))
2913 GNUNET_assert (NULL != c->t);
2914 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2915 GCT_unchoke_channels (c->t);
2919 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2920 send_ack (c, buffer, fwd, force);
2922 GCC_check_connections ();
2927 * Initialize the connections subsystem
2929 * @param c Configuration handle.
2932 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2934 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2936 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2939 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2940 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2941 GNUNET_SCHEDULER_shutdown ();
2946 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2949 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2950 "CADET", "MAX_CONNECTIONS", "MISSING");
2951 GNUNET_SCHEDULER_shutdown ();
2956 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2957 &refresh_connection_time))
2959 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2960 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2961 GNUNET_SCHEDULER_shutdown ();
2964 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2965 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2970 * Destroy each connection on shutdown.
2972 * @param cls Closure (unused).
2973 * @param key Current key code (CID, unused).
2974 * @param value Value in the hash map (`struct CadetConnection`)
2976 * @return #GNUNET_YES, because we should continue to iterate
2979 shutdown_iterator (void *cls,
2980 const struct GNUNET_HashCode *key,
2983 struct CadetConnection *c = value;
2985 c->state = CADET_CONNECTION_DESTROYED;
2992 * Shut down the connections subsystem.
2997 LOG (GNUNET_ERROR_TYPE_DEBUG, "Shutting down connections\n");
2998 GCC_check_connections ();
2999 GNUNET_CONTAINER_multihashmap_iterate (connections,
3002 GNUNET_CONTAINER_multihashmap_destroy (connections);
3008 * Create a connection.
3010 * @param cid Connection ID (either created locally or imposed remotely).
3011 * @param t Tunnel this connection belongs to (or NULL);
3012 * @param path Path this connection has to use (copy is made).
3013 * @param own_pos Own position in the @c path path.
3015 * @return Newly created connection, NULL in case of error (own id not in path).
3017 struct CadetConnection *
3018 GCC_new (const struct GNUNET_CADET_Hash *cid,
3019 struct CadetTunnel *t,
3020 struct CadetPeerPath *path,
3021 unsigned int own_pos)
3023 struct CadetConnection *c;
3024 struct CadetPeerPath *cpath;
3026 GCC_check_connections ();
3027 cpath = path_duplicate (path);
3028 GNUNET_assert (NULL != cpath);
3029 c = GNUNET_new (struct CadetConnection);
3031 GNUNET_assert (GNUNET_OK ==
3032 GNUNET_CONTAINER_multihashmap_put (connections,
3034 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
3035 fc_init (&c->fwd_fc);
3036 fc_init (&c->bck_fc);
3041 GNUNET_assert (own_pos <= cpath->length - 1);
3042 c->own_pos = own_pos;
3045 if (GNUNET_OK != register_neighbors (c))
3049 /* We were the origin of this request, this means we have invalid
3050 * info about the paths to reach the destination. We must invalidate
3051 * the *original* path to avoid trying it again in the next minute.
3053 if (2 < path->length)
3054 path_invalidate (path);
3058 GCT_debug(t, GNUNET_ERROR_TYPE_WARNING);
3062 path_destroy (c->path);
3067 LOG (GNUNET_ERROR_TYPE_INFO, "New connection %s\n", GCC_2s (c));
3068 GCC_check_connections ();
3074 GCC_destroy (struct CadetConnection *c)
3076 GCC_check_connections ();
3083 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
3084 return; /* -> message_sent -> GCC_destroy. Don't loop. */
3087 LOG (GNUNET_ERROR_TYPE_DEBUG,
3088 "destroying connection %s\n",
3090 LOG (GNUNET_ERROR_TYPE_DEBUG,
3091 " fc's f: %p, b: %p\n",
3092 &c->fwd_fc, &c->bck_fc);
3093 LOG (GNUNET_ERROR_TYPE_DEBUG,
3094 " fc tasks f: %u, b: %u\n",
3095 c->fwd_fc.poll_task,
3096 c->bck_fc.poll_task);
3098 /* Cancel all traffic */
3099 if (NULL != c->path)
3101 connection_cancel_queues (c, GNUNET_YES);
3102 connection_cancel_queues (c, GNUNET_NO);
3104 unregister_neighbors (c);
3105 path_destroy (c->path);
3108 /* Delete from tunnel */
3110 GCT_remove_connection (c->t, c);
3112 if (NULL != c->check_duplicates_task)
3113 GNUNET_SCHEDULER_cancel (c->check_duplicates_task);
3114 if (NULL != c->fwd_maintenance_task)
3115 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
3116 if (NULL != c->bck_maintenance_task)
3117 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
3119 if (GNUNET_NO == c->was_removed)
3121 GNUNET_break (GNUNET_YES ==
3122 GNUNET_CONTAINER_multihashmap_remove (connections,
3126 GNUNET_STATISTICS_update (stats,
3131 GCC_check_connections ();
3136 * Get the connection ID.
3138 * @param c Connection to get the ID from.
3140 * @return ID of the connection.
3142 const struct GNUNET_CADET_Hash *
3143 GCC_get_id (const struct CadetConnection *c)
3150 * Get the connection ID.
3152 * @param c Connection to get the ID from.
3154 * @return ID of the connection.
3156 const struct GNUNET_HashCode *
3157 GCC_get_h (const struct CadetConnection *c)
3159 return GC_h2hc (&c->id);
3164 * Get the connection path.
3166 * @param c Connection to get the path from.
3168 * @return path used by the connection.
3170 const struct CadetPeerPath *
3171 GCC_get_path (const struct CadetConnection *c)
3173 if (GNUNET_NO == c->destroy)
3180 * Get the connection state.
3182 * @param c Connection to get the state from.
3184 * @return state of the connection.
3186 enum CadetConnectionState
3187 GCC_get_state (const struct CadetConnection *c)
3193 * Get the connection tunnel.
3195 * @param c Connection to get the tunnel from.
3197 * @return tunnel of the connection.
3199 struct CadetTunnel *
3200 GCC_get_tunnel (const struct CadetConnection *c)
3207 * Get free buffer space in a connection.
3209 * @param c Connection.
3210 * @param fwd Is query about FWD traffic?
3212 * @return Free buffer space [0 - max_msgs_queue/max_connections]
3215 GCC_get_buffer (struct CadetConnection *c, int fwd)
3217 struct CadetFlowControl *fc;
3219 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3221 LOG (GNUNET_ERROR_TYPE_DEBUG, " Get %s buffer on %s: %u - %u\n",
3222 GC_f2s (fwd), GCC_2s (c), fc->queue_max, fc->queue_n);
3223 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
3225 return (fc->queue_max - fc->queue_n);
3230 * Get how many messages have we allowed to send to us from a direction.
3232 * @param c Connection.
3233 * @param fwd Are we asking about traffic from FWD (BCK messages)?
3235 * @return last_ack_sent - last_pid_recv
3238 GCC_get_allowed (struct CadetConnection *c, int fwd)
3240 struct CadetFlowControl *fc;
3242 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3243 if (CADET_CONNECTION_READY != c->state
3244 || GC_is_pid_bigger (fc->last_pid_recv, fc->last_ack_sent))
3248 return (fc->last_ack_sent - fc->last_pid_recv);
3253 * Get messages queued in a connection.
3255 * @param c Connection.
3256 * @param fwd Is query about FWD traffic?
3258 * @return Number of messages queued.
3261 GCC_get_qn (struct CadetConnection *c, int fwd)
3263 struct CadetFlowControl *fc;
3265 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3272 * Get next PID to use.
3274 * @param c Connection.
3275 * @param fwd Is query about FWD traffic?
3277 * @return Last PID used + 1.
3280 GCC_get_pid (struct CadetConnection *c, int fwd)
3282 struct CadetFlowControl *fc;
3284 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3286 return fc->last_pid_sent + 1;
3291 * Allow the connection to advertise a buffer of the given size.
3293 * The connection will send an @c fwd ACK message (so: in direction !fwd)
3294 * allowing up to last_pid_recv + buffer.
3296 * @param c Connection.
3297 * @param buffer How many more messages the connection can accept.
3298 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
3301 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
3303 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
3304 GCC_2s (c), buffer, GC_f2s (fwd));
3305 send_ack (c, buffer, fwd, GNUNET_NO);
3310 * Notify other peers on a connection of a broken link. Mark connections
3311 * to destroy after all traffic has been sent.
3313 * @param c Connection on which there has been a disconnection.
3314 * @param peer Peer that disconnected.
3317 GCC_neighbor_disconnected (struct CadetConnection *c, struct CadetPeer *peer)
3319 struct CadetPeer *hop;
3323 GCC_check_connections ();
3324 strncpy (peer_name, GCP_2s (peer), 16);
3325 peer_name[15] = '\0';
3326 LOG (GNUNET_ERROR_TYPE_DEBUG,
3327 "shutting down %s, %s disconnected\n",
3328 GCC_2s (c), peer_name);
3330 invalidate_paths (c, peer);
3332 hop = get_prev_hop (c);
3335 /* Path was NULL, we should have deleted the connection. */
3339 fwd = (peer == hop);
3340 if ( (GNUNET_YES == GCC_is_terminal (c, fwd)) ||
3341 (GNUNET_NO != c->destroy) )
3343 /* Local shutdown, or other peer already down (hence 'c->destroy');
3344 so there is no one to notify about this, just clean up. */
3346 GCC_check_connections ();
3349 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
3350 /* Connection will have at least one pending message
3351 * (the one we just scheduled), so delay destruction
3352 * and remove from map so we don't use accidentally. */
3353 c->destroy = GNUNET_YES;
3354 c->state = CADET_CONNECTION_DESTROYED;
3355 GNUNET_assert (GNUNET_NO == c->was_removed);
3356 c->was_removed = GNUNET_YES;
3357 GNUNET_break (GNUNET_YES ==
3358 GNUNET_CONTAINER_multihashmap_remove (connections,
3361 /* Cancel queue in the direction that just died. */
3362 connection_cancel_queues (c, ! fwd);
3363 GCC_stop_poll (c, ! fwd);
3364 unregister_neighbors (c);
3365 GCC_check_connections ();
3370 * Is this peer the first one on the connection?
3372 * @param c Connection.
3373 * @param fwd Is this about fwd traffic?
3375 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
3378 GCC_is_origin (struct CadetConnection *c, int fwd)
3380 if (!fwd && c->path->length - 1 == c->own_pos )
3382 if (fwd && 0 == c->own_pos)
3389 * Is this peer the last one on the connection?
3391 * @param c Connection.
3392 * @param fwd Is this about fwd traffic?
3393 * Note that the ROOT is the terminal for BCK traffic!
3395 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
3398 GCC_is_terminal (struct CadetConnection *c, int fwd)
3400 return GCC_is_origin (c, ! fwd);
3405 * See if we are allowed to send by the next hop in the given direction.
3407 * @param c Connection.
3408 * @param fwd Is this about fwd traffic?
3410 * @return #GNUNET_YES in case it's OK to send.
3413 GCC_is_sendable (struct CadetConnection *c, int fwd)
3415 struct CadetFlowControl *fc;
3417 LOG (GNUNET_ERROR_TYPE_DEBUG,
3418 " checking sendability of %s traffic on %s\n",
3419 GC_f2s (fwd), GCC_2s (c));
3425 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3426 LOG (GNUNET_ERROR_TYPE_DEBUG,
3427 " last ack recv: %u, last pid sent: %u\n",
3428 fc->last_ack_recv, fc->last_pid_sent);
3429 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
3431 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
3434 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
3440 * Check if this connection is a direct one (never trim a direct connection).
3442 * @param c Connection.
3444 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
3447 GCC_is_direct (struct CadetConnection *c)
3449 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
3454 * Sends an already built message on a connection, properly registering
3455 * all used resources.
3457 * @param message Message to send. Function makes a copy of it.
3458 * If message is not hop-by-hop, decrements TTL of copy.
3459 * @param payload_type Type of payload, in case the message is encrypted.
3460 * @param c Connection on which this message is transmitted.
3461 * @param fwd Is this a fwd message?
3462 * @param force Force the connection to accept the message (buffer overfill).
3463 * @param cont Continuation called once message is sent. Can be NULL.
3464 * @param cont_cls Closure for @c cont.
3466 * @return Handle to cancel the message before it's sent.
3467 * NULL on error or if @c cont is NULL.
3468 * Invalid on @c cont call.
3470 struct CadetConnectionQueue *
3471 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
3472 uint16_t payload_type, uint32_t payload_id,
3473 struct CadetConnection *c, int fwd, int force,
3474 GCC_sent cont, void *cont_cls)
3476 struct CadetFlowControl *fc;
3477 struct CadetConnectionQueue *q;
3483 GCC_check_connections ();
3484 size = ntohs (message->size);
3485 data = GNUNET_malloc (size);
3486 memcpy (data, message, size);
3487 type = ntohs (message->type);
3488 LOG (GNUNET_ERROR_TYPE_INFO,
3489 "--> %s (%s %4u) on conn %s (%p) %s [%5u]\n",
3490 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), c,
3493 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3494 droppable = GNUNET_NO == force;
3497 struct GNUNET_CADET_AX *axmsg;
3498 struct GNUNET_CADET_Encrypted *emsg;
3499 struct GNUNET_CADET_KX *kmsg;
3500 struct GNUNET_CADET_ACK *amsg;
3501 struct GNUNET_CADET_Poll *pmsg;
3502 struct GNUNET_CADET_ConnectionDestroy *dmsg;
3503 struct GNUNET_CADET_ConnectionBroken *bmsg;
3506 case GNUNET_MESSAGE_TYPE_CADET_AX:
3507 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
3508 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
3510 emsg = (struct GNUNET_CADET_Encrypted *) data;
3511 ttl = ntohl (emsg->ttl);
3514 GNUNET_break_op (0);
3519 emsg->ttl = htonl (ttl - 1);
3523 axmsg = (struct GNUNET_CADET_AX *) data;
3526 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
3527 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
3528 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
3529 if (GNUNET_YES == droppable)
3535 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
3539 case GNUNET_MESSAGE_TYPE_CADET_KX:
3540 kmsg = (struct GNUNET_CADET_KX *) data;
3544 case GNUNET_MESSAGE_TYPE_CADET_ACK:
3545 amsg = (struct GNUNET_CADET_ACK *) data;
3547 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
3548 droppable = GNUNET_NO;
3551 case GNUNET_MESSAGE_TYPE_CADET_POLL:
3552 pmsg = (struct GNUNET_CADET_Poll *) data;
3554 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL %u\n", ntohl (pmsg->pid));
3555 droppable = GNUNET_NO;
3558 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
3559 dmsg = (struct GNUNET_CADET_ConnectionDestroy *) data;
3563 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
3564 bmsg = (struct GNUNET_CADET_ConnectionBroken *) data;
3568 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
3569 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
3578 if (fc->queue_n > fc->queue_max && droppable)
3580 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
3583 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue full: %u/%u\n",
3584 fc->queue_n, fc->queue_max);
3585 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type
3586 || GNUNET_MESSAGE_TYPE_CADET_AX == type)
3591 return NULL; /* Drop this message */
3594 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %s %u\n",
3595 GCC_2s (c), c->pending_messages);
3596 c->pending_messages++;
3598 q = GNUNET_new (struct CadetConnectionQueue);
3599 q->forced = !droppable;
3600 q->q = GCP_queue_add (get_hop (c, fwd), data, type, payload_type, payload_id,
3601 size, c, fwd, &conn_message_sent, q);
3604 LOG (GNUNET_ERROR_TYPE_DEBUG, "dropping msg on %s, NULL q\n", GCC_2s (c));
3607 GCC_check_connections ();
3611 q->cont_cls = cont_cls;
3612 GCC_check_connections ();
3613 return (NULL == cont) ? NULL : q;
3618 * Cancel a previously sent message while it's in the queue.
3620 * ONLY can be called before the continuation given to the send function
3621 * is called. Once the continuation is called, the message is no longer in the
3624 * @param q Handle to the queue.
3627 GCC_cancel (struct CadetConnectionQueue *q)
3629 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GCC cancel message\n");
3631 /* queue destroy calls message_sent, which calls q->cont and frees q */
3632 GCP_queue_destroy (q->q, GNUNET_YES, GNUNET_NO, 0);
3633 GCC_check_connections ();
3638 * Sends a CREATE CONNECTION message for a path to a peer.
3639 * Changes the connection and tunnel states if necessary.
3641 * @param connection Connection to create.
3644 GCC_send_create (struct CadetConnection *connection)
3646 enum CadetTunnelCState state;
3649 GCC_check_connections ();
3650 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3651 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
3653 LOG (GNUNET_ERROR_TYPE_INFO, "==> %s %19s on conn %s (%p) FWD [%5u]\n",
3654 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE), "",
3655 GCC_2s (connection), connection, size);
3656 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3657 connection, connection->pending_messages);
3658 connection->pending_messages++;
3660 connection->maintenance_q =
3661 GCP_queue_add (get_next_hop (connection), NULL,
3662 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, UINT16_MAX, 0,
3663 size, connection, GNUNET_YES, &conn_message_sent, NULL);
3665 state = GCT_get_cstate (connection->t);
3666 if (CADET_TUNNEL_SEARCHING == state || CADET_TUNNEL_NEW == state)
3667 GCT_change_cstate (connection->t, CADET_TUNNEL_WAITING);
3668 if (CADET_CONNECTION_NEW == connection->state)
3669 connection_change_state (connection, CADET_CONNECTION_SENT);
3670 GCC_check_connections ();
3675 * Send a message to all peers in this connection that the connection
3676 * is no longer valid.
3678 * If some peer should not receive the message, it should be zero'ed out
3679 * before calling this function.
3681 * @param c The connection whose peers to notify.
3684 GCC_send_destroy (struct CadetConnection *c)
3686 struct GNUNET_CADET_ConnectionDestroy msg;
3688 if (GNUNET_YES == c->destroy)
3690 GCC_check_connections ();
3691 msg.header.size = htons (sizeof (msg));
3692 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
3694 LOG (GNUNET_ERROR_TYPE_DEBUG,
3695 " sending connection destroy for connection %s\n",
3698 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3699 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3701 GNUNET_YES, NULL, NULL));
3702 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3703 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, UINT16_MAX,
3705 GNUNET_YES, NULL, NULL));
3706 c->destroy = GNUNET_YES;
3707 c->state = CADET_CONNECTION_DESTROYED;
3708 GCC_check_connections ();
3713 * @brief Start a polling timer for the connection.
3715 * When a neighbor does not accept more traffic on the connection it could be
3716 * caused by a simple congestion or by a lost ACK. Polling enables to check
3717 * for the lastest ACK status for a connection.
3719 * @param c Connection.
3720 * @param fwd Should we poll in the FWD direction?
3723 GCC_start_poll (struct CadetConnection *c, int fwd)
3725 struct CadetFlowControl *fc;
3727 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3728 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL %s requested\n",
3730 if (NULL != fc->poll_task || NULL != fc->poll_msg)
3732 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL not needed (%p, %p)\n",
3733 fc->poll_task, fc->poll_msg);
3736 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL started on request\n");
3737 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
3744 * @brief Stop polling a connection for ACKs.
3746 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3748 * @param c Connection.
3749 * @param fwd Should we stop the poll in the FWD direction?
3752 GCC_stop_poll (struct CadetConnection *c, int fwd)
3754 struct CadetFlowControl *fc;
3756 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3757 if (NULL != fc->poll_task)
3759 GNUNET_SCHEDULER_cancel (fc->poll_task);
3760 fc->poll_task = NULL;
3766 * Get a (static) string for a connection.
3768 * @param c Connection.
3771 GCC_2s (const struct CadetConnection *c)
3778 static char buf[128];
3780 SPRINTF (buf, "%s (->%s)",
3781 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3784 return GNUNET_h2s (GC_h2hc (&c->id));
3789 * Log all possible info about the connection state.
3791 * @param c Connection to debug.
3792 * @param level Debug level to use.
3795 GCC_debug (const struct CadetConnection *c, enum GNUNET_ErrorType level)
3800 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
3802 __FILE__, __FUNCTION__, __LINE__);
3808 LOG2 (level, "CCC DEBUG NULL CONNECTION\n");
3812 LOG2 (level, "CCC DEBUG CONNECTION %s\n", GCC_2s (c));
3813 s = path_2s (c->path);
3814 LOG2 (level, "CCC path %s, own pos: %u\n", s, c->own_pos);
3816 LOG2 (level, "CCC state: %s, destroy: %u\n",
3817 GCC_state2s (c->state), c->destroy);
3818 LOG2 (level, "CCC pending messages: %u\n", c->pending_messages);
3819 if (NULL != c->perf)
3820 LOG2 (level, "CCC us/byte: %f\n", c->perf->avg);
3822 LOG2 (level, "CCC FWD flow control:\n");
3823 LOG2 (level, "CCC queue: %u/%u\n", c->fwd_fc.queue_n, c->fwd_fc.queue_max);
3824 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3825 c->fwd_fc.last_pid_sent, c->fwd_fc.last_pid_recv);
3826 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3827 c->fwd_fc.last_ack_sent, c->fwd_fc.last_ack_recv);
3828 LOG2 (level, "CCC recv PID bitmap: %X\n", c->fwd_fc.recv_bitmap);
3829 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3830 c->fwd_fc.poll_task, c->fwd_fc.poll_msg, c->fwd_fc.ack_msg);
3832 LOG2 (level, "CCC BCK flow control:\n");
3833 LOG2 (level, "CCC queue: %u/%u\n", c->bck_fc.queue_n, c->bck_fc.queue_max);
3834 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3835 c->bck_fc.last_pid_sent, c->bck_fc.last_pid_recv);
3836 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3837 c->bck_fc.last_ack_sent, c->bck_fc.last_ack_recv);
3838 LOG2 (level, "CCC recv PID bitmap: %X\n", c->bck_fc.recv_bitmap);
3839 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3840 c->bck_fc.poll_task, c->bck_fc.poll_msg, c->bck_fc.ack_msg);
3842 LOG2 (level, "CCC DEBUG CONNECTION END\n");