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;
258 * Handle for messages queued but not yet sent.
260 struct CadetConnectionQueue
263 * Peer queue handle, to cancel if necessary.
265 struct CadetPeerQueue *q;
268 * Continuation to call once sent.
273 * Closure for @e cont.
278 * Was this a forced message? (Do not account for it)
283 /******************************************************************************/
284 /******************************* GLOBALS ***********************************/
285 /******************************************************************************/
288 * Global handle to the statistics service.
290 extern struct GNUNET_STATISTICS_Handle *stats;
293 * Local peer own ID (memory efficient handle).
295 extern GNUNET_PEER_Id myid;
298 * Local peer own ID (full value).
300 extern struct GNUNET_PeerIdentity my_full_id;
303 * Connections known, indexed by cid (CadetConnection).
305 static struct GNUNET_CONTAINER_MultiHashMap *connections;
308 * How many connections are we willing to maintain.
309 * Local connections are always allowed, even if there are more connections than max.
311 static unsigned long long max_connections;
314 * How many messages *in total* are we willing to queue, divide by number of
315 * connections to get connection queue size.
317 static unsigned long long max_msgs_queue;
320 * How often to send path keepalives. Paths timeout after 4 missed.
322 static struct GNUNET_TIME_Relative refresh_connection_time;
325 * How often to send path create / ACKs.
327 static struct GNUNET_TIME_Relative create_connection_time;
330 /******************************************************************************/
331 /******************************** STATIC ***********************************/
332 /******************************************************************************/
336 #if 0 // avoid compiler warning for unused static function
338 fc_debug (struct CadetFlowControl *fc)
340 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
341 fc->last_pid_recv, fc->last_ack_sent);
342 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
343 fc->last_pid_sent, fc->last_ack_recv);
344 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
345 fc->queue_n, fc->queue_max);
349 connection_debug (struct CadetConnection *c)
353 LOG (GNUNET_ERROR_TYPE_INFO, "DEBUG NULL CONNECTION\n");
356 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
357 peer2s (c->t->peer), GCC_2s (c));
358 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
359 c->state, c->pending_messages);
360 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
361 fc_debug (&c->fwd_fc);
362 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
363 fc_debug (&c->bck_fc);
369 * Schedule next keepalive task, taking in consideration
370 * the connection state and number of retries.
372 * @param c Connection for which to schedule the next keepalive.
373 * @param fwd Direction for the next keepalive.
376 schedule_next_keepalive (struct CadetConnection *c, int fwd);
380 * Resets the connection timeout task, some other message has done the
382 * - For the first peer on the direction this means to send
383 * a keepalive or a path confirmation message (either create or ACK).
384 * - For all other peers, this means to destroy the connection,
385 * due to lack of activity.
386 * Starts the timeout if no timeout was running (connection just created).
388 * @param c Connection whose timeout to reset.
389 * @param fwd Is this forward?
392 connection_reset_timeout (struct CadetConnection *c, int fwd);
396 * Get string description for tunnel state. Reentrant.
398 * @param s Tunnel state.
400 * @return String representation.
403 GCC_state2s (enum CadetConnectionState s)
407 case CADET_CONNECTION_NEW:
408 return "CADET_CONNECTION_NEW";
409 case CADET_CONNECTION_SENT:
410 return "CADET_CONNECTION_SENT";
411 case CADET_CONNECTION_ACK:
412 return "CADET_CONNECTION_ACK";
413 case CADET_CONNECTION_READY:
414 return "CADET_CONNECTION_READY";
415 case CADET_CONNECTION_DESTROYED:
416 return "CADET_CONNECTION_DESTROYED";
417 case CADET_CONNECTION_BROKEN:
418 return "CADET_CONNECTION_BROKEN";
421 LOG (GNUNET_ERROR_TYPE_ERROR, " conn state %u unknown!\n", s);
422 return "CADET_CONNECTION_STATE_ERROR";
428 * Initialize a Flow Control structure to the initial state.
430 * @param fc Flow Control structure to initialize.
433 fc_init (struct CadetFlowControl *fc)
435 fc->last_pid_sent = (uint32_t) -1; /* Next (expected) = 0 */
436 fc->last_pid_recv = (uint32_t) -1;
437 fc->last_ack_sent = (uint32_t) 0;
438 fc->last_ack_recv = (uint32_t) 0;
439 fc->poll_task = NULL;
440 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
442 fc->queue_max = (max_msgs_queue / max_connections) + 1;
449 * @param cid Connection ID.
451 static struct CadetConnection *
452 connection_get (const struct GNUNET_CADET_Hash *cid)
454 return GNUNET_CONTAINER_multihashmap_get (connections, GC_h2hc (cid));
459 connection_change_state (struct CadetConnection* c,
460 enum CadetConnectionState state)
462 LOG (GNUNET_ERROR_TYPE_DEBUG,
463 "Connection %s state %s -> %s\n",
464 GCC_2s (c), GCC_state2s (c->state), GCC_state2s (state));
465 if (CADET_CONNECTION_DESTROYED <= c->state) /* Destroyed or broken. */
467 LOG (GNUNET_ERROR_TYPE_DEBUG, "state not changing anymore\n");
471 if (CADET_CONNECTION_READY == state)
477 * Callback called when a queued ACK message is sent.
479 * @param cls Closure (FC).
480 * @param c Connection this message was on.
481 * @param q Queue handler this call invalidates.
482 * @param type Type of message sent.
483 * @param fwd Was this a FWD going message?
484 * @param size Size of the message.
488 struct CadetConnection *c,
489 struct CadetConnectionQueue *q,
490 uint16_t type, int fwd, size_t size)
492 struct CadetFlowControl *fc = cls;
499 * Send an ACK on the connection, informing the predecessor about
500 * the available buffer space. Should not be called in case the peer
501 * is origin (no predecessor) in the @c fwd direction.
503 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
504 * the ACK itself goes "back" (dest->root).
506 * @param c Connection on which to send the ACK.
507 * @param buffer How much space free to advertise?
508 * @param fwd Is this FWD ACK? (Going dest -> root)
509 * @param force Don't optimize out.
512 send_ack (struct CadetConnection *c, unsigned int buffer, int fwd, int force)
514 struct CadetFlowControl *next_fc;
515 struct CadetFlowControl *prev_fc;
516 struct GNUNET_CADET_ACK msg;
520 /* If origin, there is no connection to send ACKs. Wrong function! */
521 GCC_check_connections ();
522 if (GCC_is_origin (c, fwd))
524 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection %s is origin in %s\n",
525 GCC_2s (c), GC_f2s (fwd));
530 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
531 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
533 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection send %s ack on %s\n",
534 GC_f2s (fwd), GCC_2s (c));
536 /* Check if we need to transmit the ACK. */
537 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
538 if (3 < delta && buffer < delta && GNUNET_NO == force)
540 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer > 3\n");
541 LOG (GNUNET_ERROR_TYPE_DEBUG,
542 " last pid recv: %u, last ack sent: %u\n",
543 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
544 GCC_check_connections ();
548 /* Ok, ACK might be necessary, what PID to ACK? */
549 ack = prev_fc->last_pid_recv + buffer;
550 LOG (GNUNET_ERROR_TYPE_DEBUG, " ACK %u\n", ack);
551 LOG (GNUNET_ERROR_TYPE_DEBUG,
552 " last pid %u, last ack %u, qmax %u, q %u\n",
553 prev_fc->last_pid_recv, prev_fc->last_ack_sent,
554 next_fc->queue_max, next_fc->queue_n);
555 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
557 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
558 GCC_check_connections ();
562 /* Check if message is already in queue */
563 if (NULL != prev_fc->ack_msg)
565 if (GC_is_pid_bigger (ack, prev_fc->last_ack_sent))
567 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
568 GCC_cancel (prev_fc->ack_msg);
569 /* GCC_cancel triggers ack_sent(), which clears fc->ack_msg */
573 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
574 GCC_check_connections ();
579 prev_fc->last_ack_sent = ack;
581 /* Build ACK message and send on connection */
582 msg.header.size = htons (sizeof (msg));
583 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_ACK);
584 msg.ack = htonl (ack);
587 prev_fc->ack_msg = GCC_send_prebuilt_message (&msg.header, 0, ack, c,
590 GNUNET_assert (NULL != prev_fc->ack_msg);
591 GCC_check_connections ();
596 * Callback called when a connection queued message is sent.
598 * Calculates the average time and connection packet tracking.
600 * @param cls Closure (ConnectionQueue Handle).
601 * @param c Connection this message was on.
602 * @param sent Was it really sent? (Could have been canceled)
603 * @param type Type of message sent.
604 * @param pid Packet ID, or 0 if not applicable (create, destroy, etc).
605 * @param fwd Was this a FWD going message?
606 * @param size Size of the message.
607 * @param wait Time spent waiting for core (only the time for THIS message)
608 * @return #GNUNET_YES if connection was destroyed, #GNUNET_NO otherwise.
611 conn_message_sent (void *cls,
612 struct CadetConnection *c, int sent,
613 uint16_t type, uint32_t pid, int fwd, size_t size,
614 struct GNUNET_TIME_Relative wait)
616 struct CadetConnectionPerformance *p;
617 struct CadetFlowControl *fc;
618 struct CadetConnectionQueue *q = cls;
622 GCC_check_connections ();
623 LOG (GNUNET_ERROR_TYPE_DEBUG, "connection message_sent\n");
625 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
627 fc = fwd ? &c->fwd_fc : &c->bck_fc;
628 LOG (GNUNET_ERROR_TYPE_DEBUG, " %ssent %s %s pid %u\n",
629 sent ? "" : "not ", GC_f2s (fwd), GC_m2s (type), pid);
635 LOG (GNUNET_ERROR_TYPE_DEBUG, " calling cont\n");
636 q->cont (q->cont_cls, c, q, type, fwd, size);
640 else if (type == GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED
641 || type == GNUNET_MESSAGE_TYPE_CADET_AX)
643 /* If NULL == q and ENCRYPTED == type, message must have been ch_mngmnt */
652 if (type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN
653 && type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY)
655 LOG (GNUNET_ERROR_TYPE_ERROR, "Message %s sent on NULL connection!\n",
658 GCC_check_connections ();
661 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P- %p %u\n", c, c->pending_messages);
662 c->pending_messages--;
663 if ( (GNUNET_YES == c->destroy) &&
664 (0 == c->pending_messages) )
666 LOG (GNUNET_ERROR_TYPE_DEBUG,
667 "! destroying connection!\n");
669 GCC_check_connections ();
672 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
675 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
676 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
677 c->maintenance_q = NULL;
678 /* Don't trigger a keepalive for sent ACKs, only SYN and SYNACKs */
679 if (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE == type || !fwd)
680 schedule_next_keepalive (c, fwd);
683 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
684 case GNUNET_MESSAGE_TYPE_CADET_AX:
685 if (GNUNET_YES == sent)
687 GNUNET_assert (NULL != q);
688 fc->last_pid_sent = pid;
689 if (GC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
690 GCC_start_poll (c, fwd);
691 GCC_send_ack (c, fwd, GNUNET_NO);
692 connection_reset_timeout (c, fwd);
695 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
696 if (GNUNET_NO == forced)
699 LOG (GNUNET_ERROR_TYPE_DEBUG,
700 "! accounting pid %u\n",
705 LOG (GNUNET_ERROR_TYPE_DEBUG,
706 "! forced, Q_N not accounting pid %u\n",
711 case GNUNET_MESSAGE_TYPE_CADET_KX:
712 if (GNUNET_YES == sent)
713 connection_reset_timeout (c, fwd);
716 case GNUNET_MESSAGE_TYPE_CADET_POLL:
720 case GNUNET_MESSAGE_TYPE_CADET_ACK:
724 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
728 LOG (GNUNET_ERROR_TYPE_ERROR, "%s unknown\n", GC_m2s (type));
732 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
735 return GNUNET_NO; /* Only endpoints are interested in timing. */
738 usecsperbyte = ((double) wait.rel_value_us) / size;
739 if (p->size == AVG_MSGS)
741 /* Array is full. Substract oldest value, add new one and store. */
742 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
743 p->usecsperbyte[p->idx] = usecsperbyte;
744 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
748 /* Array not yet full. Add current value to avg and store. */
749 p->usecsperbyte[p->idx] = usecsperbyte;
751 p->avg += p->usecsperbyte[p->idx];
755 p->idx = (p->idx + 1) % AVG_MSGS;
756 GCC_check_connections ();
762 * Get the previous hop in a connection
764 * @param c Connection.
766 * @return Previous peer in the connection.
768 static struct CadetPeer *
769 get_prev_hop (const struct CadetConnection *c)
775 LOG (GNUNET_ERROR_TYPE_DEBUG,
776 " get prev hop %s [%u/%u]\n",
777 GCC_2s (c), c->own_pos, c->path->length);
778 if (0 == c->own_pos || c->path->length < 2)
779 id = c->path->peers[0];
781 id = c->path->peers[c->own_pos - 1];
783 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
784 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
786 return GCP_get_short (id, GNUNET_YES);
791 * Get the next hop in a connection
793 * @param c Connection.
795 * @return Next peer in the connection.
797 static struct CadetPeer *
798 get_next_hop (const struct CadetConnection *c)
805 LOG (GNUNET_ERROR_TYPE_DEBUG, " get next hop %s [%u/%u]\n",
806 GCC_2s (c), c->own_pos, c->path->length);
807 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
808 id = c->path->peers[c->path->length - 1];
810 id = c->path->peers[c->own_pos + 1];
812 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
813 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
815 return GCP_get_short (id, GNUNET_YES);
820 * Check that the direct neighbours (previous and next hop)
821 * are properly associated with this connection.
823 * @param c connection to check
826 check_neighbours (const struct CadetConnection *c)
829 return; /* nothing to check */
830 GCP_check_connection (get_next_hop (c), c);
831 GCP_check_connection (get_prev_hop (c), c);
836 * Helper for #check_connections(). Calls #check_neighbours().
840 * @param value the `struct CadetConnection` to check
841 * @return #GNUNET_OK (continue to iterate)
844 check_connection (void *cls,
845 const struct GNUNET_HashCode *key,
848 struct CadetConnection *c = value;
850 check_neighbours (c);
856 * Check invariants for all connections using #check_neighbours().
859 GCC_check_connections ()
861 if (0 == CHECK_INVARIANTS)
863 if (NULL == connections)
865 GNUNET_CONTAINER_multihashmap_iterate (connections,
872 * Get the hop in a connection.
874 * @param c Connection.
875 * @param fwd Next in the FWD direction?
877 * @return Next peer in the connection.
879 static struct CadetPeer *
880 get_hop (struct CadetConnection *c, int fwd)
882 return (fwd) ? get_next_hop (c) : get_prev_hop (c);
887 * Get a bit mask for a message received out-of-order.
889 * @param last_pid_recv Last PID we received prior to the out-of-order.
890 * @param ooo_pid PID of the out-of-order message.
893 get_recv_bitmask (uint32_t last_pid_recv, uint32_t ooo_pid)
895 return 1 << (last_pid_recv - ooo_pid);
900 * Check is an out-of-order message is ok:
901 * - at most 31 messages behind.
904 * @param last_pid_recv Last in-order PID received.
907 is_ooo_ok (uint32_t last_pid_recv, uint32_t ooo_pid, uint32_t ooo_bitmap)
911 if (GC_is_pid_bigger (last_pid_recv - 31, ooo_pid))
914 mask = get_recv_bitmask (last_pid_recv, ooo_pid);
915 if (0 != (ooo_bitmap & mask))
923 * Is traffic coming from this sender 'FWD' traffic?
925 * @param c Connection to check.
926 * @param sender Peer identity of neighbor.
928 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
929 * the traffic is 'FWD'.
930 * #GNUNET_NO for BCK.
931 * #GNUNET_SYSERR for errors.
934 is_fwd (const struct CadetConnection *c,
935 const struct GNUNET_PeerIdentity *sender)
939 id = GNUNET_PEER_search (sender);
940 if (GCP_get_short_id (get_prev_hop (c)) == id)
943 if (GCP_get_short_id (get_next_hop (c)) == id)
947 return GNUNET_SYSERR;
952 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
953 * or a first CONNECTION_ACK directed to us.
955 * @param connection Connection to confirm.
956 * @param fwd Should we send it FWD? (root->dest)
957 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
960 send_connection_ack (struct CadetConnection *connection, int fwd)
962 struct CadetTunnel *t;
964 GCC_check_connections ();
966 LOG (GNUNET_ERROR_TYPE_INFO, "---> {%14s ACK} on connection %s\n",
967 GC_f2s (!fwd), GCC_2s (connection));
968 GCP_queue_add (get_hop (connection, fwd), NULL,
969 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK, 0, 0,
970 sizeof (struct GNUNET_CADET_ConnectionACK),
971 connection, fwd, &conn_message_sent, NULL);
972 connection->pending_messages++;
973 if (CADET_TUNNEL_NEW == GCT_get_cstate (t))
974 GCT_change_cstate (t, CADET_TUNNEL_WAITING);
975 if (CADET_CONNECTION_READY != connection->state)
976 connection_change_state (connection, CADET_CONNECTION_SENT);
977 GCC_check_connections ();
982 * Send a notification that a connection is broken.
984 * @param c Connection that is broken.
985 * @param id1 Peer that has disconnected.
986 * @param id2 Peer that has disconnected.
987 * @param fwd Direction towards which to send it.
990 send_broken (struct CadetConnection *c,
991 const struct GNUNET_PeerIdentity *id1,
992 const struct GNUNET_PeerIdentity *id2,
995 struct GNUNET_CADET_ConnectionBroken msg;
997 GCC_check_connections ();
998 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
999 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1003 GNUNET_assert (NULL ==
1004 GCC_send_prebuilt_message (&msg.header, 0, 0, c, fwd,
1005 GNUNET_YES, NULL, NULL));
1006 GCC_check_connections ();
1011 * Send a notification that a connection is broken, when a connection
1012 * isn't even known to the local peer or soon to be destroyed.
1014 * @param connection_id Connection ID.
1015 * @param id1 Peer that has disconnected, probably local peer.
1016 * @param id2 Peer that has disconnected can be NULL if unknown.
1017 * @param peer Peer to notify (neighbor who sent the connection).
1020 send_broken_unknown (const struct GNUNET_CADET_Hash *connection_id,
1021 const struct GNUNET_PeerIdentity *id1,
1022 const struct GNUNET_PeerIdentity *id2,
1023 const struct GNUNET_PeerIdentity *peer_id)
1025 struct GNUNET_CADET_ConnectionBroken *msg;
1026 struct CadetPeer *neighbor;
1028 GCC_check_connections ();
1029 LOG (GNUNET_ERROR_TYPE_INFO, "---> BROKEN on unknown connection %s\n",
1030 GNUNET_h2s (GC_h2hc (connection_id)));
1032 msg = GNUNET_new (struct GNUNET_CADET_ConnectionBroken);
1033 msg->header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1034 msg->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1035 msg->cid = *connection_id;
1040 memset (&msg->peer2, 0, sizeof (msg->peer2));
1041 neighbor = GCP_get (peer_id, GNUNET_NO); /* We MUST know neighbor. */
1042 GNUNET_assert (NULL != neighbor);
1043 GCP_queue_add (neighbor, msg, GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN,
1044 0, 2, sizeof (struct GNUNET_CADET_ConnectionBroken),
1045 NULL, GNUNET_SYSERR, /* connection, fwd */
1046 NULL, NULL); /* continuation */
1047 GCC_check_connections ();
1052 * Send keepalive packets for a connection.
1054 * @param c Connection to keep alive..
1055 * @param fwd Is this a FWD keepalive? (owner -> dest).
1058 send_connection_keepalive (struct CadetConnection *c, int fwd)
1060 struct GNUNET_MessageHeader msg;
1061 struct CadetFlowControl *fc;
1063 GCC_check_connections ();
1064 LOG (GNUNET_ERROR_TYPE_INFO,
1065 "keepalive %s for connection %s\n",
1066 GC_f2s (fwd), GCC_2s (c));
1068 GNUNET_assert (NULL != c->t);
1069 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1070 if (0 < fc->queue_n || GNUNET_YES == GCT_has_queued_traffic (c->t))
1072 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, traffic in queue\n");
1076 GNUNET_STATISTICS_update (stats, "# keepalives sent", 1, GNUNET_NO);
1078 GNUNET_assert (NULL != c->t);
1079 msg.size = htons (sizeof (msg));
1080 msg.type = htons (GNUNET_MESSAGE_TYPE_CADET_KEEPALIVE);
1082 GNUNET_assert (NULL ==
1083 GCT_send_prebuilt_message (&msg, c->t, c,
1084 GNUNET_NO, NULL, NULL));
1085 GCC_check_connections ();
1090 * Send CONNECTION_{CREATE/ACK} packets for a connection.
1092 * @param c Connection for which to send the message.
1093 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
1096 connection_recreate (struct CadetConnection *c, int fwd)
1098 LOG (GNUNET_ERROR_TYPE_DEBUG,
1099 "sending connection recreate\n");
1101 GCC_send_create (c);
1103 send_connection_ack (c, GNUNET_NO);
1108 * Generic connection timer management.
1109 * Depending on the role of the peer in the connection will send the
1110 * appropriate message (build or keepalive)
1112 * @param c Conncetion to maintain.
1113 * @param fwd Is FWD?
1116 connection_maintain (struct CadetConnection *c, int fwd)
1118 if (GNUNET_NO != c->destroy)
1120 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, being destroyed\n");
1127 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1131 if (CADET_TUNNEL_SEARCHING == GCT_get_cstate (c->t))
1133 /* If status is SEARCHING, why is there a connection? Should be WAITING */
1135 GCT_debug (c->t, GNUNET_ERROR_TYPE_ERROR);
1136 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, tunnel SEARCHING\n");
1137 schedule_next_keepalive (c, fwd);
1142 case CADET_CONNECTION_NEW:
1145 case CADET_CONNECTION_SENT:
1146 connection_recreate (c, fwd);
1148 case CADET_CONNECTION_READY:
1149 send_connection_keepalive (c, fwd);
1158 * Keep the connection alive.
1160 * @param c Connection to keep alive.
1161 * @param fwd Direction.
1162 * @param shutdown Are we shutting down? (Don't send traffic)
1163 * Non-zero value for true, not necessarily GNUNET_YES.
1166 connection_keepalive (struct CadetConnection *c, int fwd, int shutdown)
1168 GCC_check_connections ();
1169 LOG (GNUNET_ERROR_TYPE_DEBUG,
1170 "%s keepalive for %s\n",
1171 GC_f2s (fwd), GCC_2s (c));
1174 c->fwd_maintenance_task = NULL;
1176 c->bck_maintenance_task = NULL;
1178 if (GNUNET_NO != shutdown)
1181 connection_maintain (c, fwd);
1182 GCC_check_connections ();
1183 /* Next execution will be scheduled by message_sent or _maintain*/
1188 * Keep the connection alive in the FWD direction.
1190 * @param cls Closure (connection to keepalive).
1191 * @param tc TaskContext.
1194 connection_fwd_keepalive (void *cls,
1195 const struct GNUNET_SCHEDULER_TaskContext *tc)
1197 GCC_check_connections ();
1198 connection_keepalive ((struct CadetConnection *) cls,
1200 tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN);
1201 GCC_check_connections ();
1206 * Keep the connection alive in the BCK direction.
1208 * @param cls Closure (connection to keepalive).
1209 * @param tc TaskContext.
1212 connection_bck_keepalive (void *cls,
1213 const struct GNUNET_SCHEDULER_TaskContext *tc)
1215 GCC_check_connections ();
1216 connection_keepalive ((struct CadetConnection *) cls,
1218 tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN);
1219 GCC_check_connections ();
1224 * Schedule next keepalive task, taking in consideration
1225 * the connection state and number of retries.
1227 * If the peer is not the origin, do nothing.
1229 * @param c Connection for which to schedule the next keepalive.
1230 * @param fwd Direction for the next keepalive.
1233 schedule_next_keepalive (struct CadetConnection *c, int fwd)
1235 struct GNUNET_TIME_Relative delay;
1236 struct GNUNET_SCHEDULER_Task * *task_id;
1237 GNUNET_SCHEDULER_TaskCallback keepalive_task;
1239 GCC_check_connections ();
1240 if (GNUNET_NO == GCC_is_origin (c, fwd))
1243 /* Calculate delay to use, depending on the state of the connection */
1244 if (CADET_CONNECTION_READY == c->state)
1246 delay = refresh_connection_time;
1250 if (1 > c->create_retry)
1251 c->create_retry = 1;
1252 delay = GNUNET_TIME_relative_multiply (create_connection_time,
1254 if (c->create_retry < 64)
1255 c->create_retry *= 2;
1258 /* Select direction-dependent parameters */
1259 if (GNUNET_YES == fwd)
1261 task_id = &c->fwd_maintenance_task;
1262 keepalive_task = &connection_fwd_keepalive;
1266 task_id = &c->bck_maintenance_task;
1267 keepalive_task = &connection_bck_keepalive;
1270 /* Check that no one scheduled it before us */
1271 if (NULL != *task_id)
1273 /* No need for a _break. It can happen for instance when sending a SYNACK
1274 * for a duplicate SYN: the first SYNACK scheduled the task. */
1275 GNUNET_SCHEDULER_cancel (*task_id);
1278 /* Schedule the task */
1279 *task_id = GNUNET_SCHEDULER_add_delayed (delay,
1282 LOG (GNUNET_ERROR_TYPE_DEBUG, "next keepalive in %s\n",
1283 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1284 GCC_check_connections ();
1289 * @brief Re-initiate traffic on this connection if necessary.
1291 * Check if there is traffic queued towards this peer
1292 * and the core transmit handle is NULL (traffic was stalled).
1293 * If so, call core tmt rdy.
1295 * @param c Connection on which initiate traffic.
1296 * @param fwd Is this about fwd traffic?
1299 connection_unlock_queue (struct CadetConnection *c, int fwd)
1301 struct CadetPeer *peer;
1303 GCC_check_connections ();
1304 LOG (GNUNET_ERROR_TYPE_DEBUG,
1305 "connection_unlock_queue %s on %s\n",
1306 GC_f2s (fwd), GCC_2s (c));
1308 if (GCC_is_terminal (c, fwd))
1310 LOG (GNUNET_ERROR_TYPE_DEBUG, " is terminal, can unlock!\n");
1314 peer = get_hop (c, fwd);
1315 GCP_queue_unlock (peer, c);
1316 GCC_check_connections ();
1321 * Cancel all transmissions that belong to a certain connection.
1323 * If the connection is scheduled for destruction and no more messages are left,
1324 * the connection will be destroyed by the continuation call.
1326 * @param c Connection which to cancel. Might be destroyed during this call.
1327 * @param fwd Cancel fwd traffic?
1330 connection_cancel_queues (struct CadetConnection *c,
1333 struct CadetFlowControl *fc;
1334 struct CadetPeer *peer;
1336 GCC_check_connections ();
1337 LOG (GNUNET_ERROR_TYPE_DEBUG,
1338 "Cancel %s queues for connection %s\n",
1339 GC_f2s (fwd), GCC_2s (c));
1346 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1347 if (NULL != fc->poll_task)
1349 GNUNET_SCHEDULER_cancel (fc->poll_task);
1350 fc->poll_task = NULL;
1351 LOG (GNUNET_ERROR_TYPE_DEBUG, "Cancel POLL in ccq for fc %p\n", fc);
1353 peer = get_hop (c, fwd);
1354 GCP_queue_cancel (peer, c);
1355 GCC_check_connections ();
1360 * Function called if a connection has been stalled for a while,
1361 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1363 * @param cls Closure (poll ctx).
1364 * @param tc TaskContext.
1367 connection_poll (void *cls,
1368 const struct GNUNET_SCHEDULER_TaskContext *tc);
1372 * Callback called when a queued POLL message is sent.
1374 * @param cls Closure (FC).
1375 * @param c Connection this message was on.
1376 * @param q Queue handler this call invalidates.
1377 * @param type Type of message sent.
1378 * @param fwd Was this a FWD going message?
1379 * @param size Size of the message.
1382 poll_sent (void *cls,
1383 struct CadetConnection *c,
1384 struct CadetConnectionQueue *q,
1385 uint16_t type, int fwd, size_t size)
1387 struct CadetFlowControl *fc = cls;
1389 if (2 == c->destroy)
1391 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL canceled on shutdown\n");
1394 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL sent for %s, scheduling new one!\n",
1396 fc->poll_msg = NULL;
1397 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
1398 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
1401 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
1406 * Function called if a connection has been stalled for a while,
1407 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1409 * @param cls Closure (poll ctx).
1410 * @param tc TaskContext.
1413 connection_poll (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1415 struct CadetFlowControl *fc = cls;
1416 struct GNUNET_CADET_Poll msg;
1417 struct CadetConnection *c;
1420 fc->poll_task = NULL;
1421 GCC_check_connections ();
1422 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1428 fwd = fc == &c->fwd_fc;
1429 LOG (GNUNET_ERROR_TYPE_DEBUG, "Polling connection %s %s\n",
1430 GCC_2s (c), GC_f2s (fwd));
1432 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_POLL);
1433 msg.header.size = htons (sizeof (msg));
1434 msg.pid = htonl (fc->last_pid_sent);
1435 LOG (GNUNET_ERROR_TYPE_DEBUG, " last pid sent: %u\n", fc->last_pid_sent);
1437 GCC_send_prebuilt_message (&msg.header, 0, fc->last_pid_sent, c,
1438 fc == &c->fwd_fc, GNUNET_YES, &poll_sent, fc);
1439 GNUNET_assert (NULL != fc->poll_msg);
1440 GCC_check_connections ();
1445 * Resend all queued messages for a connection on other connections of the
1446 * same tunnel, if possible. The connection WILL BE DESTROYED by this function.
1448 * @param c Connection whose messages to resend.
1449 * @param fwd Resend fwd messages?
1452 resend_messages_and_destroy (struct CadetConnection *c, int fwd)
1454 struct GNUNET_MessageHeader *out_msg;
1455 struct CadetTunnel *t = c->t;
1456 struct CadetPeer *neighbor;
1457 unsigned int pending;
1460 GCC_check_connections ();
1461 c->state = CADET_CONNECTION_DESTROYED;
1462 c->destroy = GNUNET_YES;
1464 destroyed = GNUNET_NO;
1465 neighbor = get_hop (c, fwd);
1466 pending = c->pending_messages;
1468 while (NULL != (out_msg = GCP_connection_pop (neighbor, c, &destroyed)))
1471 GCT_resend_message (out_msg, t);
1472 GNUNET_free (out_msg);
1475 /* All pending messages should have been popped,
1476 * and the connection destroyed by the continuation.
1478 if (GNUNET_YES != destroyed)
1483 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1484 if (NULL != t) GCT_debug (t, GNUNET_ERROR_TYPE_ERROR);
1488 GCC_check_connections ();
1493 * Generic connection timeout implementation.
1495 * Timeout function due to lack of keepalive/traffic from an endpoint.
1496 * Destroys connection if called.
1498 * @param c Connection to destroy.
1499 * @param fwd Was the timeout from the origin? (FWD timeout)
1502 connection_timeout (struct CadetConnection *c, int fwd)
1504 struct CadetFlowControl *reverse_fc;
1506 GCC_check_connections ();
1507 reverse_fc = fwd ? &c->bck_fc : &c->fwd_fc;
1509 LOG (GNUNET_ERROR_TYPE_INFO,
1510 "Connection %s %s timed out. Destroying.\n",
1513 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1515 if (GCC_is_origin (c, fwd)) /* Loopback? Something is wrong! */
1521 /* If dest, salvage queued traffic. */
1522 if (GCC_is_origin (c, !fwd))
1524 const struct GNUNET_PeerIdentity *next_hop;
1526 next_hop = GCP_get_id (fwd ? get_prev_hop (c) : get_next_hop (c));
1527 send_broken_unknown (&c->id, &my_full_id, NULL, next_hop);
1528 if (0 < reverse_fc->queue_n)
1529 resend_messages_and_destroy (c, !fwd);
1530 GCC_check_connections ();
1535 GCC_check_connections ();
1540 * Timeout function due to lack of keepalive/traffic from the owner.
1541 * Destroys connection if called.
1543 * @param cls Closure (connection to destroy).
1544 * @param tc TaskContext.
1547 connection_fwd_timeout (void *cls,
1548 const struct GNUNET_SCHEDULER_TaskContext *tc)
1550 struct CadetConnection *c = cls;
1552 c->fwd_maintenance_task = NULL;
1553 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1555 GCC_check_connections ();
1556 connection_timeout (c, GNUNET_YES);
1557 GCC_check_connections ();
1562 * Timeout function due to lack of keepalive/traffic from the destination.
1563 * Destroys connection if called.
1565 * @param cls Closure (connection to destroy).
1566 * @param tc TaskContext
1569 connection_bck_timeout (void *cls,
1570 const struct GNUNET_SCHEDULER_TaskContext *tc)
1572 struct CadetConnection *c = cls;
1574 c->bck_maintenance_task = NULL;
1575 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1577 GCC_check_connections ();
1578 connection_timeout (c, GNUNET_NO);
1579 GCC_check_connections ();
1584 * Resets the connection timeout task, some other message has done the
1586 * - For the first peer on the direction this means to send
1587 * a keepalive or a path confirmation message (either create or ACK).
1588 * - For all other peers, this means to destroy the connection,
1589 * due to lack of activity.
1590 * Starts the timeout if no timeout was running (connection just created).
1592 * @param c Connection whose timeout to reset.
1593 * @param fwd Is this forward?
1595 * TODO use heap to improve efficiency of scheduler.
1598 connection_reset_timeout (struct CadetConnection *c, int fwd)
1600 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1601 if (GCC_is_origin (c, fwd)) /* Startpoint */
1603 schedule_next_keepalive (c, fwd);
1605 else /* Relay, endpoint. */
1607 struct GNUNET_TIME_Relative delay;
1608 struct GNUNET_SCHEDULER_Task * *ti;
1609 GNUNET_SCHEDULER_TaskCallback f;
1611 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1614 GNUNET_SCHEDULER_cancel (*ti);
1615 delay = GNUNET_TIME_relative_multiply (refresh_connection_time, 4);
1616 LOG (GNUNET_ERROR_TYPE_DEBUG, " timing out in %s\n",
1617 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_NO));
1618 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1619 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1625 * Add the connection to the list of both neighbors.
1627 * @param c Connection.
1629 * @return #GNUNET_OK if everything went fine
1630 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1633 register_neighbors (struct CadetConnection *c)
1635 c->next_peer = get_next_hop (c);
1636 c->prev_peer = get_prev_hop (c);
1637 GNUNET_assert (c->next_peer != c->prev_peer);
1638 LOG (GNUNET_ERROR_TYPE_DEBUG,
1639 "register neighbors for connection %s\n",
1641 path_debug (c->path);
1642 LOG (GNUNET_ERROR_TYPE_DEBUG,
1643 "own pos %u\n", c->own_pos);
1644 LOG (GNUNET_ERROR_TYPE_DEBUG,
1645 "putting connection %s to next peer %p\n",
1648 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n",
1650 GCP_2s (c->next_peer));
1651 LOG (GNUNET_ERROR_TYPE_DEBUG,
1652 "putting connection %s to prev peer %p\n",
1655 LOG (GNUNET_ERROR_TYPE_DEBUG,
1656 "prev peer %p %s\n",
1658 GCP_2s (c->prev_peer));
1660 if ( (GNUNET_NO == GCP_is_neighbor (c->next_peer)) ||
1661 (GNUNET_NO == GCP_is_neighbor (c->prev_peer)) )
1663 if (GCC_is_origin (c, GNUNET_YES))
1664 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1665 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1667 LOG (GNUNET_ERROR_TYPE_DEBUG,
1668 " register neighbors failed\n");
1669 LOG (GNUNET_ERROR_TYPE_DEBUG,
1670 " prev: %s, neighbor?: %d\n",
1671 GCP_2s (c->prev_peer),
1672 GCP_is_neighbor (c->prev_peer));
1673 LOG (GNUNET_ERROR_TYPE_DEBUG,
1674 " next: %s, neighbor?: %d\n",
1675 GCP_2s (c->next_peer),
1676 GCP_is_neighbor (c->next_peer));
1677 return GNUNET_SYSERR;
1679 GCP_add_connection (c->next_peer, c, GNUNET_NO);
1680 GCP_add_connection (c->prev_peer, c, GNUNET_YES);
1687 * Remove the connection from the list of both neighbors.
1689 * @param c Connection.
1692 unregister_neighbors (struct CadetConnection *c)
1694 /* Either already unregistered or never got registered, it's ok either way. */
1695 if (NULL == c->path)
1697 if (NULL != c->next_peer)
1699 GCP_remove_connection (c->next_peer, c);
1700 c->next_peer = NULL;
1702 if (NULL != c->prev_peer)
1704 GCP_remove_connection (c->prev_peer, c);
1705 c->prev_peer = NULL;
1711 * Bind the connection to the peer and the tunnel to that peer.
1713 * If the peer has no tunnel, create one. Update tunnel and connection
1714 * data structres to reflect new status.
1716 * @param c Connection.
1720 add_to_peer (struct CadetConnection *c,
1721 struct CadetPeer *peer)
1723 GCP_add_tunnel (peer);
1724 c->t = GCP_get_tunnel (peer);
1725 GCT_add_connection (c->t, c);
1730 * Iterator to compare each connection's path with the path of a new connection.
1732 * If the connection conincides, the c member of path is set to the connection
1733 * and the destroy flag of the connection is set.
1735 * @param cls Closure (new path).
1736 * @param c Connection in the tunnel to check.
1739 check_path (void *cls, struct CadetConnection *c)
1741 struct CadetConnection *new_conn = cls;
1742 struct CadetPeerPath *path = new_conn->path;
1744 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking %s (%p), length %u\n",
1745 GCC_2s (c), c, c->path->length);
1748 && c->destroy == GNUNET_NO
1749 && c->state != CADET_CONNECTION_BROKEN
1750 && c->state != CADET_CONNECTION_DESTROYED
1751 && path_equivalent (path, c->path))
1753 new_conn->destroy = GNUNET_YES;
1754 new_conn->path->c = c;
1755 LOG (GNUNET_ERROR_TYPE_DEBUG, " MATCH!\n");
1761 * Finds out if this path is already being used by and existing connection.
1763 * Checks the tunnel towards the first peer in the path to see if it contains
1764 * any connection with the same path.
1766 * If the existing connection is ready, it is kept.
1767 * Otherwise if the sender has a smaller ID that ours, we accept it (and
1768 * the peer will eventually reject our attempt).
1770 * @param path Path to check.
1771 * @return #GNUNET_YES if the tunnel has a connection with the same path,
1772 * #GNUNET_NO otherwise.
1775 does_connection_exist (struct CadetConnection *conn)
1777 struct CadetPeer *p;
1778 struct CadetTunnel *t;
1779 struct CadetConnection *c;
1781 p = GCP_get_short (conn->path->peers[0], GNUNET_NO);
1784 t = GCP_get_tunnel (p);
1788 LOG (GNUNET_ERROR_TYPE_DEBUG,
1789 "Checking for duplicates\n");
1791 GCT_iterate_connections (t, &check_path, conn);
1793 if (GNUNET_YES == conn->destroy)
1796 conn->destroy = GNUNET_NO;
1797 conn->path->c = conn;
1798 LOG (GNUNET_ERROR_TYPE_DEBUG, " found duplicate of %s\n", GCC_2s (conn));
1799 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate: %s\n", GCC_2s (c));
1800 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1801 if (CADET_CONNECTION_READY == c->state)
1803 /* The other peer confirmed a live connection with this path,
1804 * why is it trying to duplicate it. */
1808 if (GNUNET_CRYPTO_cmp_peer_identity (&my_full_id, GCP_get_id (p)) > 0)
1810 struct CadetPeer *neighbor;
1812 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate allowed (killing old)\n");
1813 if (GCC_is_origin (c, GNUNET_YES))
1814 neighbor = get_next_hop (c);
1816 neighbor = get_prev_hop (c);
1817 send_broken_unknown (&c->id, &my_full_id, NULL,
1818 GCP_get_id (neighbor));
1827 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s has no duplicates\n", GCC_2s (conn));
1834 * Log receipt of message on stderr (INFO level).
1836 * @param message Message received.
1837 * @param peer Peer who sent the message.
1838 * @param hash Connection ID.
1841 log_message (const struct GNUNET_MessageHeader *message,
1842 const struct GNUNET_PeerIdentity *peer,
1843 const struct GNUNET_CADET_Hash *hash)
1847 size = ntohs (message->size);
1848 LOG (GNUNET_ERROR_TYPE_INFO, "\n");
1849 LOG (GNUNET_ERROR_TYPE_INFO, "\n");
1850 LOG (GNUNET_ERROR_TYPE_INFO, "<-- %s on connection %s from %s, %6u bytes\n",
1851 GC_m2s (ntohs (message->type)), GNUNET_h2s (GC_h2hc (hash)),
1852 GNUNET_i2s (peer), (unsigned int) size);
1855 /******************************************************************************/
1856 /******************************** API ***********************************/
1857 /******************************************************************************/
1860 * Core handler for connection creation.
1862 * @param cls Closure (unused).
1863 * @param peer Sender (neighbor).
1864 * @param message Message.
1865 * @return #GNUNET_OK to keep the connection open,
1866 * #GNUNET_SYSERR to close it (signal serious error)
1869 GCC_handle_create (void *cls,
1870 const struct GNUNET_PeerIdentity *peer,
1871 const struct GNUNET_MessageHeader *message)
1873 struct GNUNET_CADET_ConnectionCreate *msg;
1874 struct GNUNET_PeerIdentity *id;
1875 struct GNUNET_CADET_Hash *cid;
1876 struct CadetPeerPath *path;
1877 struct CadetPeer *dest_peer;
1878 struct CadetPeer *orig_peer;
1879 struct CadetConnection *c;
1880 unsigned int own_pos;
1883 GCC_check_connections ();
1885 size = ntohs (message->size);
1886 if (size < sizeof (struct GNUNET_CADET_ConnectionCreate))
1888 GNUNET_break_op (0);
1892 /* Calculate hops */
1893 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
1894 if (size % sizeof (struct GNUNET_PeerIdentity))
1896 GNUNET_break_op (0);
1899 if (0 != size % sizeof (struct GNUNET_PeerIdentity))
1901 GNUNET_break_op (0);
1904 size /= sizeof (struct GNUNET_PeerIdentity);
1907 GNUNET_break_op (0);
1910 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1912 /* Get parameters */
1913 msg = (struct GNUNET_CADET_ConnectionCreate *) message;
1915 log_message (message, peer, cid);
1916 id = (struct GNUNET_PeerIdentity *) &msg[1];
1917 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
1919 /* Create connection */
1920 c = connection_get (cid);
1923 path = path_build_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
1924 size, myid, &own_pos);
1927 /* Path was malformed, probably our own ID was not in it. */
1928 GNUNET_STATISTICS_update (stats, "# malformed paths", 1, GNUNET_NO);
1929 GNUNET_break_op (0);
1935 /* We received this request from a neighbor, we cannot be origin */
1936 GNUNET_STATISTICS_update (stats, "# fake paths", 1, GNUNET_NO);
1937 GNUNET_break_op (0);
1938 path_destroy (path);
1942 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1943 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1944 c = GCC_new (cid, NULL, path, own_pos);
1947 if (path->length - 1 == own_pos)
1949 /* If we are destination, why did the creation fail? */
1951 path_destroy (path);
1952 GCC_check_connections ();
1955 send_broken_unknown (cid, &my_full_id,
1956 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
1958 path_destroy (path);
1959 GCC_check_connections ();
1962 GCP_add_path_to_all (path, GNUNET_NO);
1963 connection_reset_timeout (c, GNUNET_YES);
1967 path = path_duplicate (c->path);
1969 if (CADET_CONNECTION_NEW == c->state)
1970 connection_change_state (c, CADET_CONNECTION_SENT);
1972 /* Remember peers */
1973 dest_peer = GCP_get (&id[size - 1], GNUNET_YES);
1974 orig_peer = GCP_get (&id[0], GNUNET_YES);
1976 /* Is it a connection to us? */
1977 if (c->own_pos == path->length - 1)
1979 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1980 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
1982 add_to_peer (c, orig_peer);
1983 if (GNUNET_YES == does_connection_exist (c))
1985 // FIXME Peer created a connection equal to one we think exists
1986 // and is fine. What should we do?
1987 // Use explicit duplicate?
1988 // Accept new conn and destroy the old? (interruption in higher level)
1989 // Keep both and postpone disambiguation?
1990 // Keep the one created by peer with higher ID?
1991 // For now: reject new connection until current confirmed dead
1992 GNUNET_break_op (0);
1993 GCC_debug (c, GNUNET_ERROR_TYPE_WARNING);
1994 path_destroy (path);
1996 send_broken_unknown (cid, &my_full_id, NULL, peer);
1997 GCC_check_connections ();
2001 if (CADET_TUNNEL_NEW == GCT_get_cstate (c->t))
2002 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
2004 send_connection_ack (c, GNUNET_NO);
2005 if (CADET_CONNECTION_SENT == c->state)
2006 connection_change_state (c, CADET_CONNECTION_ACK);
2010 /* It's for somebody else! Retransmit. */
2011 LOG (GNUNET_ERROR_TYPE_DEBUG, " Retransmitting.\n");
2012 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
2013 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
2014 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c,
2015 GNUNET_YES, GNUNET_YES,
2018 path_destroy (path);
2019 GCC_check_connections ();
2025 * Core handler for path confirmations.
2027 * @param cls closure
2028 * @param message message
2029 * @param peer peer identity this notification is about
2030 * @return #GNUNET_OK to keep the connection open,
2031 * #GNUNET_SYSERR to close it (signal serious error)
2034 GCC_handle_confirm (void *cls,
2035 const struct GNUNET_PeerIdentity *peer,
2036 const struct GNUNET_MessageHeader *message)
2038 struct GNUNET_CADET_ConnectionACK *msg;
2039 struct CadetConnection *c;
2040 struct CadetPeerPath *p;
2041 struct CadetPeer *pi;
2042 enum CadetConnectionState oldstate;
2045 GCC_check_connections ();
2046 msg = (struct GNUNET_CADET_ConnectionACK *) message;
2047 log_message (message, peer, &msg->cid);
2048 c = connection_get (&msg->cid);
2051 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
2053 LOG (GNUNET_ERROR_TYPE_DEBUG,
2054 " don't know the connection!\n");
2055 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2056 GCC_check_connections ();
2060 oldstate = c->state;
2061 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GNUNET_i2s (peer));
2062 pi = GCP_get (peer, GNUNET_YES);
2063 if (get_next_hop (c) == pi)
2065 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
2067 if (CADET_CONNECTION_SENT == oldstate)
2068 connection_change_state (c, CADET_CONNECTION_ACK);
2070 else if (get_prev_hop (c) == pi)
2072 LOG (GNUNET_ERROR_TYPE_DEBUG, " FINAL ACK\n");
2074 connection_change_state (c, CADET_CONNECTION_READY);
2078 GNUNET_break_op (0);
2082 connection_reset_timeout (c, fwd);
2084 /* Add path to peers? */
2088 GCP_add_path_to_all (p, GNUNET_YES);
2095 /* Message for us as creator? */
2096 if (GCC_is_origin (c, GNUNET_YES))
2098 if (GNUNET_NO != fwd)
2100 GNUNET_break_op (0);
2103 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
2105 /* If just created, cancel the short timeout and start a long one */
2106 if (CADET_CONNECTION_SENT == oldstate)
2107 connection_reset_timeout (c, GNUNET_YES);
2109 /* Change connection state */
2110 connection_change_state (c, CADET_CONNECTION_READY);
2111 send_connection_ack (c, GNUNET_YES);
2113 /* Change tunnel state, trigger KX */
2114 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2115 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2116 GCC_check_connections ();
2120 /* Message for us as destination? */
2121 if (GCC_is_terminal (c, GNUNET_YES))
2123 if (GNUNET_YES != fwd)
2125 GNUNET_break_op (0);
2128 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
2130 /* If just created, cancel the short timeout and start a long one */
2131 if (CADET_CONNECTION_ACK == oldstate)
2132 connection_reset_timeout (c, GNUNET_NO);
2134 /* Change tunnel state */
2135 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2136 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2137 GCC_check_connections ();
2141 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2142 GNUNET_assert (NULL ==
2143 GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2144 GNUNET_YES, NULL, NULL));
2145 GCC_check_connections ();
2151 * Core handler for notifications of broken connections.
2153 * @param cls Closure (unused).
2154 * @param id Peer identity of sending neighbor.
2155 * @param message Message.
2156 * @return #GNUNET_OK to keep the connection open,
2157 * #GNUNET_SYSERR to close it (signal serious error)
2160 GCC_handle_broken (void* cls,
2161 const struct GNUNET_PeerIdentity* id,
2162 const struct GNUNET_MessageHeader* message)
2164 struct GNUNET_CADET_ConnectionBroken *msg;
2165 struct CadetConnection *c;
2166 struct CadetTunnel *t;
2170 GCC_check_connections ();
2171 msg = (struct GNUNET_CADET_ConnectionBroken *) message;
2172 log_message (message, id, &msg->cid);
2173 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2174 GNUNET_i2s (&msg->peer1));
2175 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n",
2176 GNUNET_i2s (&msg->peer2));
2177 c = connection_get (&msg->cid);
2180 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
2181 GCC_check_connections ();
2187 fwd = is_fwd (c, id);
2188 c->destroy = GNUNET_YES;
2189 if (GCC_is_terminal (c, fwd))
2191 struct CadetPeer *endpoint;
2195 /* A terminal connection should not have 't' set to NULL. */
2197 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
2200 endpoint = GCP_get_short (c->path->peers[c->path->length - 1], GNUNET_YES);
2201 if (2 < c->path->length)
2202 path_invalidate (c->path);
2203 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
2205 c->state = CADET_CONNECTION_BROKEN;
2206 GCT_remove_connection (t, c);
2209 pending = c->pending_messages;
2211 resend_messages_and_destroy (c, !fwd);
2217 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2218 GNUNET_YES, NULL, NULL));
2219 connection_cancel_queues (c, !fwd);
2221 GCC_check_connections ();
2227 * Core handler for tunnel destruction
2229 * @param cls Closure (unused).
2230 * @param peer Peer identity of sending neighbor.
2231 * @param message Message.
2232 * @return #GNUNET_OK to keep the connection open,
2233 * #GNUNET_SYSERR to close it (signal serious error)
2236 GCC_handle_destroy (void *cls,
2237 const struct GNUNET_PeerIdentity *peer,
2238 const struct GNUNET_MessageHeader *message)
2240 const struct GNUNET_CADET_ConnectionDestroy *msg;
2241 struct CadetConnection *c;
2244 GCC_check_connections ();
2245 msg = (const struct GNUNET_CADET_ConnectionDestroy *) message;
2246 log_message (message, peer, &msg->cid);
2247 c = connection_get (&msg->cid);
2250 /* Probably already got the message from another path,
2251 * destroyed the tunnel and retransmitted to children.
2254 GNUNET_STATISTICS_update (stats,
2255 "# control on unknown connection",
2257 LOG (GNUNET_ERROR_TYPE_DEBUG,
2258 " connection unknown: already destroyed?\n");
2259 GCC_check_connections ();
2262 fwd = is_fwd (c, peer);
2263 if (GNUNET_SYSERR == fwd)
2265 GNUNET_break_op (0); /* FIXME */
2268 if (GNUNET_NO == GCC_is_terminal (c, fwd))
2270 GNUNET_assert (NULL ==
2271 GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2272 GNUNET_YES, NULL, NULL));
2274 else if (0 == c->pending_messages)
2276 LOG (GNUNET_ERROR_TYPE_DEBUG,
2277 " directly destroying connection!\n");
2279 GCC_check_connections ();
2282 c->destroy = GNUNET_YES;
2283 c->state = CADET_CONNECTION_DESTROYED;
2286 GCT_remove_connection (c->t, c);
2289 GCC_check_connections ();
2295 * Check the message against internal state and test if it goes FWD or BCK.
2297 * Updates the PID, state and timeout values for the connection.
2299 * @param message Message to check. It must belong to an existing connection.
2300 * @param minimum_size The message cannot be smaller than this value.
2301 * @param cid Connection ID (even if @a c is NULL, the ID is still needed).
2302 * @param c Connection this message should belong. If NULL, check fails.
2303 * @param neighbor Neighbor that sent the message.
2306 check_message (const struct GNUNET_MessageHeader *message,
2307 size_t minimum_size,
2308 const struct GNUNET_CADET_Hash* cid,
2309 struct CadetConnection *c,
2310 const struct GNUNET_PeerIdentity *neighbor,
2313 GNUNET_PEER_Id neighbor_id;
2314 struct CadetFlowControl *fc;
2315 struct CadetPeer *hop;
2320 if (ntohs (message->size) < minimum_size)
2322 GNUNET_break_op (0);
2323 LOG (GNUNET_ERROR_TYPE_WARNING, "Size %u < %u\n",
2324 ntohs (message->size), minimum_size);
2325 return GNUNET_SYSERR;
2328 /* Check connection */
2331 GNUNET_STATISTICS_update (stats,
2332 "# unknown connection",
2334 LOG (GNUNET_ERROR_TYPE_DEBUG,
2335 "%s on unknown connection %s\n",
2336 GC_m2s (ntohs (message->type)),
2337 GNUNET_h2s (GC_h2hc (cid)));
2338 send_broken_unknown (cid,
2342 return GNUNET_SYSERR;
2345 /* Check if origin is as expected */
2346 neighbor_id = GNUNET_PEER_search (neighbor);
2347 hop = get_prev_hop (c);
2348 if (neighbor_id == GCP_get_short_id (hop))
2354 hop = get_next_hop (c);
2355 GNUNET_break (hop == c->next_peer);
2356 if (neighbor_id == GCP_get_short_id (hop))
2362 /* Unexpected peer sending traffic on a connection. */
2363 GNUNET_break_op (0);
2364 return GNUNET_SYSERR;
2368 /* Check PID for payload messages */
2369 type = ntohs (message->type);
2370 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type
2371 || GNUNET_MESSAGE_TYPE_CADET_AX == type)
2373 fc = fwd ? &c->bck_fc : &c->fwd_fc;
2374 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u - %u)\n",
2375 pid, fc->last_pid_recv + 1, fc->last_ack_sent);
2376 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
2378 GNUNET_break_op (0);
2379 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
2380 LOG (GNUNET_ERROR_TYPE_WARNING, "Received PID %u, (prev %u), ACK %u\n",
2381 pid, fc->last_pid_recv, fc->last_ack_sent);
2382 return GNUNET_SYSERR;
2384 if (GC_is_pid_bigger (pid, fc->last_pid_recv))
2388 delta = pid - fc->last_pid_recv;
2389 fc->last_pid_recv = pid;
2390 fc->recv_bitmap <<= delta;
2391 fc->recv_bitmap |= 1;
2395 GNUNET_STATISTICS_update (stats, "# out of order PID", 1, GNUNET_NO);
2396 if (GNUNET_NO == is_ooo_ok (fc->last_pid_recv, pid, fc->recv_bitmap))
2398 LOG (GNUNET_ERROR_TYPE_WARNING, "PID %u unexpected (%u+), dropping!\n",
2399 pid, fc->last_pid_recv - 31);
2400 return GNUNET_SYSERR;
2402 fc->recv_bitmap |= get_recv_bitmask (fc->last_pid_recv, pid);
2406 /* Count as connection confirmation. */
2407 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2409 connection_change_state (c, CADET_CONNECTION_READY);
2412 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2413 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2416 connection_reset_timeout (c, fwd);
2423 * Generic handler for cadet network encrypted traffic.
2425 * @param peer Peer identity this notification is about.
2426 * @param msg Encrypted message.
2427 * @return #GNUNET_OK to keep the connection open,
2428 * #GNUNET_SYSERR to close it (signal serious error)
2431 handle_cadet_encrypted (const struct GNUNET_PeerIdentity *peer,
2432 const struct GNUNET_MessageHeader *message)
2434 const struct GNUNET_CADET_Encrypted *otr_msg;
2435 const struct GNUNET_CADET_AX *ax_msg;
2436 const struct GNUNET_CADET_Hash* cid;
2437 struct CadetConnection *c;
2438 size_t minumum_size;
2444 GCC_check_connections ();
2445 if (GNUNET_MESSAGE_TYPE_CADET_AX == ntohs (message->type))
2447 overhead = sizeof (struct GNUNET_CADET_AX);
2448 ax_msg = (const struct GNUNET_CADET_AX *) message;
2450 pid = ntohl (ax_msg->pid);
2455 overhead = sizeof (struct GNUNET_CADET_Encrypted);
2456 otr_msg = (const struct GNUNET_CADET_Encrypted *) message;
2457 cid = &otr_msg->cid;
2458 pid = ntohl (otr_msg->pid);
2461 log_message (message, peer, cid);
2463 minumum_size = sizeof (struct GNUNET_MessageHeader) + overhead;
2464 c = connection_get (cid);
2465 fwd = check_message (message,
2472 /* If something went wrong, discard message. */
2473 if (GNUNET_SYSERR == fwd)
2475 GCC_check_connections ();
2479 /* Is this message for us? */
2480 if (GCC_is_terminal (c, fwd))
2482 GNUNET_STATISTICS_update (stats, "# received encrypted", 1, GNUNET_NO);
2486 GNUNET_break (GNUNET_NO != c->destroy);
2489 GCT_handle_encrypted (c->t, message);
2490 GCC_send_ack (c, fwd, GNUNET_NO);
2491 GCC_check_connections ();
2495 /* Message not for us: forward to next hop */
2496 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2497 if (NULL != otr_msg) /* only otr has ttl */
2499 ttl = ntohl (otr_msg->ttl);
2500 LOG (GNUNET_ERROR_TYPE_DEBUG, " ttl: %u\n", ttl);
2503 GNUNET_STATISTICS_update (stats, "# TTL drops", 1, GNUNET_NO);
2504 LOG (GNUNET_ERROR_TYPE_WARNING, " TTL is 0, DROPPING!\n");
2505 GCC_send_ack (c, fwd, GNUNET_NO);
2506 GCC_check_connections ();
2511 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2512 GNUNET_assert (NULL == GCC_send_prebuilt_message (message, 0, 0, c, fwd,
2513 GNUNET_NO, NULL, NULL));
2514 GCC_check_connections ();
2520 * Generic handler for cadet network encrypted traffic.
2522 * @param peer Peer identity this notification is about.
2523 * @param msg Encrypted message.
2524 * @return #GNUNET_OK to keep the connection open,
2525 * #GNUNET_SYSERR to close it (signal serious error)
2528 handle_cadet_kx (const struct GNUNET_PeerIdentity *peer,
2529 const struct GNUNET_CADET_KX *msg)
2531 const struct GNUNET_CADET_Hash* cid;
2532 struct CadetConnection *c;
2533 size_t expected_size;
2536 GCC_check_connections ();
2538 log_message (&msg->header, peer, cid);
2540 expected_size = sizeof (struct GNUNET_CADET_KX)
2541 + sizeof (struct GNUNET_MessageHeader);
2542 c = connection_get (cid);
2543 fwd = check_message (&msg->header,
2550 /* If something went wrong, discard message. */
2551 if (GNUNET_SYSERR == fwd)
2554 /* Is this message for us? */
2555 if (GCC_is_terminal (c, fwd))
2557 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2558 GNUNET_STATISTICS_update (stats, "# received KX", 1, GNUNET_NO);
2564 GCT_handle_kx (c->t, &msg[1].header);
2565 GCC_check_connections ();
2569 /* Message not for us: forward to next hop */
2570 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2571 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2572 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2573 GNUNET_NO, NULL, NULL));
2574 GCC_check_connections ();
2580 * Core handler for key exchange traffic (ephemeral key, ping, pong).
2582 * @param cls Closure (unused).
2583 * @param message Message received.
2584 * @param peer Peer who sent the message.
2585 * @return #GNUNET_OK to keep the connection open,
2586 * #GNUNET_SYSERR to close it (signal serious error)
2589 GCC_handle_kx (void *cls,
2590 const struct GNUNET_PeerIdentity *peer,
2591 const struct GNUNET_MessageHeader *message)
2593 GCC_check_connections ();
2594 return handle_cadet_kx (peer, (struct GNUNET_CADET_KX *) message);
2599 * Core handler for encrypted cadet network traffic (channel mgmt, data).
2601 * @param cls Closure (unused).
2602 * @param message Message received.
2603 * @param peer Peer who sent the message.
2604 * @return #GNUNET_OK to keep the connection open,
2605 * #GNUNET_SYSERR to close it (signal serious error)
2608 GCC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
2609 const struct GNUNET_MessageHeader *message)
2611 GCC_check_connections ();
2612 return handle_cadet_encrypted (peer, message);
2617 * Core handler for cadet network traffic point-to-point acks.
2619 * @param cls closure
2620 * @param message message
2621 * @param peer peer identity this notification is about
2622 * @return #GNUNET_OK to keep the connection open,
2623 * #GNUNET_SYSERR to close it (signal serious error)
2626 GCC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
2627 const struct GNUNET_MessageHeader *message)
2629 struct GNUNET_CADET_ACK *msg;
2630 struct CadetConnection *c;
2631 struct CadetFlowControl *fc;
2636 GCC_check_connections ();
2637 msg = (struct GNUNET_CADET_ACK *) message;
2638 log_message (message, peer, &msg->cid);
2639 c = connection_get (&msg->cid);
2642 GNUNET_STATISTICS_update (stats,
2643 "# ack on unknown connection",
2646 send_broken_unknown (&msg->cid,
2650 GCC_check_connections ();
2654 /* Is this a forward or backward ACK? */
2655 id = GNUNET_PEER_search (peer);
2656 if (GCP_get_short_id (get_next_hop (c)) == id)
2661 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2668 GNUNET_break_op (0);
2672 ack = ntohl (msg->ack);
2673 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s ACK %u (was %u)\n",
2674 GC_f2s (fwd), ack, fc->last_ack_recv);
2675 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2676 fc->last_ack_recv = ack;
2678 /* Cancel polling if the ACK is big enough. */
2679 if (NULL != fc->poll_task &&
2680 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2682 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2683 GNUNET_SCHEDULER_cancel (fc->poll_task);
2684 fc->poll_task = NULL;
2685 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2688 connection_unlock_queue (c, fwd);
2689 GCC_check_connections ();
2695 * Core handler for cadet network traffic point-to-point ack polls.
2697 * @param cls closure
2698 * @param message message
2699 * @param peer peer identity this notification is about
2700 * @return #GNUNET_OK to keep the connection open,
2701 * #GNUNET_SYSERR to close it (signal serious error)
2704 GCC_handle_poll (void *cls,
2705 const struct GNUNET_PeerIdentity *peer,
2706 const struct GNUNET_MessageHeader *message)
2708 struct GNUNET_CADET_Poll *msg;
2709 struct CadetConnection *c;
2710 struct CadetFlowControl *fc;
2715 GCC_check_connections ();
2716 msg = (struct GNUNET_CADET_Poll *) message;
2717 log_message (message, peer, &msg->cid);
2718 c = connection_get (&msg->cid);
2721 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2723 LOG (GNUNET_ERROR_TYPE_DEBUG,
2724 "POLL message on unknown connection %s!\n",
2725 GNUNET_h2s (GC_h2hc (&msg->cid)));
2726 send_broken_unknown (&msg->cid,
2730 GCC_check_connections ();
2734 /* Is this a forward or backward ACK?
2735 * Note: a poll should never be needed in a loopback case,
2736 * since there is no possiblility of packet loss there, so
2737 * this way of discerining FWD/BCK should not be a problem.
2739 id = GNUNET_PEER_search (peer);
2740 if (GCP_get_short_id (get_next_hop (c)) == id)
2742 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2745 else if (GCP_get_short_id (get_prev_hop (c)) == id)
2747 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2752 GNUNET_break_op (0);
2756 pid = ntohl (msg->pid);
2757 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2758 fc->last_pid_recv = pid;
2759 fwd = fc == &c->bck_fc;
2760 GCC_send_ack (c, fwd, GNUNET_YES);
2761 GCC_check_connections ();
2768 * Send an ACK on the appropriate connection/channel, depending on
2769 * the direction and the position of the peer.
2771 * @param c Which connection to send the hop-by-hop ACK.
2772 * @param fwd Is this a fwd ACK? (will go dest->root).
2773 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
2776 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
2778 unsigned int buffer;
2780 GCC_check_connections ();
2781 LOG (GNUNET_ERROR_TYPE_DEBUG, "GCC send %s ACK on %s\n",
2782 GC_f2s (fwd), GCC_2s (c));
2790 if (GNUNET_NO != c->destroy)
2792 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
2793 GCC_check_connections ();
2797 /* Get available buffer space */
2798 if (GCC_is_terminal (c, fwd))
2800 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
2801 buffer = GCT_get_channels_buffer (c->t);
2805 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
2806 buffer = GCC_get_buffer (c, fwd);
2808 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
2809 if (0 == buffer && GNUNET_NO == force)
2811 GCC_check_connections ();
2815 /* Send available buffer space */
2816 if (GCC_is_origin (c, fwd))
2818 GNUNET_assert (NULL != c->t);
2819 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
2820 GCT_unchoke_channels (c->t);
2824 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
2825 send_ack (c, buffer, fwd, force);
2827 GCC_check_connections ();
2832 * Initialize the connections subsystem
2834 * @param c Configuration handle.
2837 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2839 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2841 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2844 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2845 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2846 GNUNET_SCHEDULER_shutdown ();
2851 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2854 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2855 "CADET", "MAX_CONNECTIONS", "MISSING");
2856 GNUNET_SCHEDULER_shutdown ();
2861 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2862 &refresh_connection_time))
2864 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2865 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2866 GNUNET_SCHEDULER_shutdown ();
2869 create_connection_time = GNUNET_TIME_UNIT_SECONDS;
2870 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2875 * Destroy each connection on shutdown.
2877 * @param cls Closure (unused).
2878 * @param key Current key code (CID, unused).
2879 * @param value Value in the hash map (`struct CadetConnection`)
2881 * @return #GNUNET_YES, because we should continue to iterate
2884 shutdown_iterator (void *cls,
2885 const struct GNUNET_HashCode *key,
2888 struct CadetConnection *c = value;
2890 c->state = CADET_CONNECTION_DESTROYED;
2897 * Shut down the connections subsystem.
2902 GCC_check_connections ();
2903 GNUNET_CONTAINER_multihashmap_iterate (connections,
2906 GNUNET_CONTAINER_multihashmap_destroy (connections);
2912 * Create a connection.
2914 * @param cid Connection ID (either created locally or imposed remotely).
2915 * @param t Tunnel this connection belongs to (or NULL);
2916 * @param path Path this connection has to use (copy is made).
2917 * @param own_pos Own position in the @c path path.
2919 * @return Newly created connection, NULL in case of error (own id not in path).
2921 struct CadetConnection *
2922 GCC_new (const struct GNUNET_CADET_Hash *cid,
2923 struct CadetTunnel *t,
2924 struct CadetPeerPath *path,
2925 unsigned int own_pos)
2927 struct CadetConnection *c;
2928 struct CadetPeerPath *p;
2930 GCC_check_connections ();
2931 p = path_duplicate (path);
2932 c = GNUNET_new (struct CadetConnection);
2934 GNUNET_assert (GNUNET_OK ==
2935 GNUNET_CONTAINER_multihashmap_put (connections,
2937 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2938 fc_init (&c->fwd_fc);
2939 fc_init (&c->bck_fc);
2944 GNUNET_assert (own_pos <= p->length - 1);
2945 c->own_pos = own_pos;
2948 GNUNET_assert (NULL != p);
2949 if (GNUNET_OK != register_neighbors (c))
2953 /* We were the origin of this request, this means we have invalid
2954 * info about the paths to reach the destination. We must invalidate
2955 * the *original* path to avoid trying it again in the next minute.
2957 path_invalidate (path);
2960 path_destroy (c->path);
2965 LOG (GNUNET_ERROR_TYPE_INFO, "New connection %s\n", GCC_2s (c));
2966 GCC_check_connections ();
2972 GCC_destroy (struct CadetConnection *c)
2974 GCC_check_connections ();
2981 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
2982 return; /* -> message_sent -> GCC_destroy. Don't loop. */
2985 LOG (GNUNET_ERROR_TYPE_DEBUG,
2986 "destroying connection %s\n",
2988 LOG (GNUNET_ERROR_TYPE_DEBUG,
2989 " fc's f: %p, b: %p\n",
2990 &c->fwd_fc, &c->bck_fc);
2991 LOG (GNUNET_ERROR_TYPE_DEBUG,
2992 " fc tasks f: %u, b: %u\n",
2993 c->fwd_fc.poll_task,
2994 c->bck_fc.poll_task);
2996 /* Cancel all traffic */
2997 if (NULL != c->path)
2999 connection_cancel_queues (c, GNUNET_YES);
3000 connection_cancel_queues (c, GNUNET_NO);
3002 unregister_neighbors (c);
3003 path_destroy (c->path);
3006 /* Cancel maintainance task (keepalive/timeout) */
3007 if (NULL != c->fwd_fc.poll_msg)
3009 GCC_cancel (c->fwd_fc.poll_msg);
3010 LOG (GNUNET_ERROR_TYPE_DEBUG,
3011 " POLL msg FWD canceled\n");
3013 if (NULL != c->bck_fc.poll_msg)
3015 GCC_cancel (c->bck_fc.poll_msg);
3016 LOG (GNUNET_ERROR_TYPE_DEBUG,
3017 " POLL msg BCK canceled\n");
3020 /* Delete from tunnel */
3022 GCT_remove_connection (c->t, c);
3024 if (NULL != c->fwd_maintenance_task)
3025 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
3026 if (NULL != c->bck_maintenance_task)
3027 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
3028 if (NULL != c->fwd_fc.poll_task)
3030 GNUNET_SCHEDULER_cancel (c->fwd_fc.poll_task);
3031 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL task FWD canceled\n");
3033 if (NULL != c->bck_fc.poll_task)
3035 GNUNET_SCHEDULER_cancel (c->bck_fc.poll_task);
3036 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL task BCK canceled\n");
3038 if (GNUNET_NO == c->was_removed)
3040 GNUNET_break (GNUNET_YES ==
3041 GNUNET_CONTAINER_multihashmap_remove (connections,
3045 GNUNET_STATISTICS_update (stats,
3050 GCC_check_connections ();
3055 * Get the connection ID.
3057 * @param c Connection to get the ID from.
3059 * @return ID of the connection.
3061 const struct GNUNET_CADET_Hash *
3062 GCC_get_id (const struct CadetConnection *c)
3069 * Get the connection ID.
3071 * @param c Connection to get the ID from.
3073 * @return ID of the connection.
3075 const struct GNUNET_HashCode *
3076 GCC_get_h (const struct CadetConnection *c)
3078 return GC_h2hc (&c->id);
3083 * Get the connection path.
3085 * @param c Connection to get the path from.
3087 * @return path used by the connection.
3089 const struct CadetPeerPath *
3090 GCC_get_path (const struct CadetConnection *c)
3092 if (GNUNET_NO == c->destroy)
3099 * Get the connection state.
3101 * @param c Connection to get the state from.
3103 * @return state of the connection.
3105 enum CadetConnectionState
3106 GCC_get_state (const struct CadetConnection *c)
3112 * Get the connection tunnel.
3114 * @param c Connection to get the tunnel from.
3116 * @return tunnel of the connection.
3118 struct CadetTunnel *
3119 GCC_get_tunnel (const struct CadetConnection *c)
3126 * Get free buffer space in a connection.
3128 * @param c Connection.
3129 * @param fwd Is query about FWD traffic?
3131 * @return Free buffer space [0 - max_msgs_queue/max_connections]
3134 GCC_get_buffer (struct CadetConnection *c, int fwd)
3136 struct CadetFlowControl *fc;
3138 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3140 LOG (GNUNET_ERROR_TYPE_DEBUG, " Get %s buffer on %s: %u - %u\n",
3141 GC_f2s (fwd), GCC_2s (c), fc->queue_max, fc->queue_n);
3142 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
3144 return (fc->queue_max - fc->queue_n);
3149 * Get how many messages have we allowed to send to us from a direction.
3151 * @param c Connection.
3152 * @param fwd Are we asking about traffic from FWD (BCK messages)?
3154 * @return last_ack_sent - last_pid_recv
3157 GCC_get_allowed (struct CadetConnection *c, int fwd)
3159 struct CadetFlowControl *fc;
3161 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3162 if (CADET_CONNECTION_READY != c->state
3163 || GC_is_pid_bigger (fc->last_pid_recv, fc->last_ack_sent))
3167 return (fc->last_ack_sent - fc->last_pid_recv);
3172 * Get messages queued in a connection.
3174 * @param c Connection.
3175 * @param fwd Is query about FWD traffic?
3177 * @return Number of messages queued.
3180 GCC_get_qn (struct CadetConnection *c, int fwd)
3182 struct CadetFlowControl *fc;
3184 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3191 * Get next PID to use.
3193 * @param c Connection.
3194 * @param fwd Is query about FWD traffic?
3196 * @return Last PID used + 1.
3199 GCC_get_pid (struct CadetConnection *c, int fwd)
3201 struct CadetFlowControl *fc;
3203 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3205 return fc->last_pid_sent + 1;
3210 * Allow the connection to advertise a buffer of the given size.
3212 * The connection will send an @c fwd ACK message (so: in direction !fwd)
3213 * allowing up to last_pid_recv + buffer.
3215 * @param c Connection.
3216 * @param buffer How many more messages the connection can accept.
3217 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
3220 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
3222 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
3223 GCC_2s (c), buffer, GC_f2s (fwd));
3224 send_ack (c, buffer, fwd, GNUNET_NO);
3229 * Notify other peers on a connection of a broken link. Mark connections
3230 * to destroy after all traffic has been sent.
3232 * @param c Connection on which there has been a disconnection.
3233 * @param peer Peer that disconnected.
3236 GCC_notify_broken (struct CadetConnection *c,
3237 struct CadetPeer *peer)
3239 struct CadetPeer *hop;
3242 GCC_check_connections ();
3243 LOG (GNUNET_ERROR_TYPE_DEBUG,
3244 "Notify broken on %s due to %s disconnect\n",
3247 hop = get_prev_hop (c);
3250 /* Path was NULL, we should have deleted the connection. */
3254 fwd = (peer == hop);
3255 if ( (GNUNET_YES == GCC_is_terminal (c, fwd)) ||
3256 (GNUNET_YES == c->destroy) )
3258 /* Local shutdown, or other peer already down (hence 'c->destroy');
3259 so there is no one to notify about this, just clean up. */
3261 GCC_check_connections ();
3264 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
3265 /* Connection will have at least one pending message
3266 * (the one we just scheduled), so delay destruction
3267 * and remove from map so we don't use accidentally. */
3268 c->destroy = GNUNET_YES;
3269 c->state = CADET_CONNECTION_DESTROYED;
3270 GNUNET_assert (GNUNET_NO == c->was_removed);
3271 c->was_removed = GNUNET_YES;
3272 GNUNET_break (GNUNET_YES ==
3273 GNUNET_CONTAINER_multihashmap_remove (connections,
3276 /* Cancel queue in the direction that just died. */
3277 connection_cancel_queues (c, ! fwd);
3278 unregister_neighbors (c);
3279 GCC_check_connections ();
3284 * Is this peer the first one on the connection?
3286 * @param c Connection.
3287 * @param fwd Is this about fwd traffic?
3289 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
3292 GCC_is_origin (struct CadetConnection *c, int fwd)
3294 if (!fwd && c->path->length - 1 == c->own_pos )
3296 if (fwd && 0 == c->own_pos)
3303 * Is this peer the last one on the connection?
3305 * @param c Connection.
3306 * @param fwd Is this about fwd traffic?
3307 * Note that the ROOT is the terminal for BCK traffic!
3309 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
3312 GCC_is_terminal (struct CadetConnection *c, int fwd)
3314 return GCC_is_origin (c, ! fwd);
3319 * See if we are allowed to send by the next hop in the given direction.
3321 * @param c Connection.
3322 * @param fwd Is this about fwd traffic?
3324 * @return #GNUNET_YES in case it's OK to send.
3327 GCC_is_sendable (struct CadetConnection *c, int fwd)
3329 struct CadetFlowControl *fc;
3331 LOG (GNUNET_ERROR_TYPE_DEBUG,
3332 " checking sendability of %s traffic on %s\n",
3333 GC_f2s (fwd), GCC_2s (c));
3339 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3340 LOG (GNUNET_ERROR_TYPE_DEBUG,
3341 " last ack recv: %u, last pid sent: %u\n",
3342 fc->last_ack_recv, fc->last_pid_sent);
3343 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
3345 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
3348 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
3354 * Check if this connection is a direct one (never trim a direct connection).
3356 * @param c Connection.
3358 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
3361 GCC_is_direct (struct CadetConnection *c)
3363 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
3368 * Sends an already built message on a connection, properly registering
3369 * all used resources.
3371 * @param message Message to send. Function makes a copy of it.
3372 * If message is not hop-by-hop, decrements TTL of copy.
3373 * @param payload_type Type of payload, in case the message is encrypted.
3374 * @param c Connection on which this message is transmitted.
3375 * @param fwd Is this a fwd message?
3376 * @param force Force the connection to accept the message (buffer overfill).
3377 * @param cont Continuation called once message is sent. Can be NULL.
3378 * @param cont_cls Closure for @c cont.
3380 * @return Handle to cancel the message before it's sent.
3381 * NULL on error or if @c cont is NULL.
3382 * Invalid on @c cont call.
3384 struct CadetConnectionQueue *
3385 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
3386 uint16_t payload_type, uint32_t payload_id,
3387 struct CadetConnection *c, int fwd, int force,
3388 GCC_sent cont, void *cont_cls)
3390 struct CadetFlowControl *fc;
3391 struct CadetConnectionQueue *q;
3397 GCC_check_connections ();
3398 size = ntohs (message->size);
3399 data = GNUNET_malloc (size);
3400 memcpy (data, message, size);
3401 type = ntohs (message->type);
3402 LOG (GNUNET_ERROR_TYPE_INFO, "--> %s (%s %4u) on connection %s (%u bytes)\n",
3403 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), size);
3405 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3406 droppable = GNUNET_NO == force;
3409 struct GNUNET_CADET_AX *axmsg;
3410 struct GNUNET_CADET_Encrypted *emsg;
3411 struct GNUNET_CADET_KX *kmsg;
3412 struct GNUNET_CADET_ACK *amsg;
3413 struct GNUNET_CADET_Poll *pmsg;
3414 struct GNUNET_CADET_ConnectionDestroy *dmsg;
3415 struct GNUNET_CADET_ConnectionBroken *bmsg;
3418 case GNUNET_MESSAGE_TYPE_CADET_AX:
3419 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
3420 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
3422 emsg = (struct GNUNET_CADET_Encrypted *) data;
3423 ttl = ntohl (emsg->ttl);
3426 GNUNET_break_op (0);
3431 emsg->ttl = htonl (ttl - 1);
3435 axmsg = (struct GNUNET_CADET_AX *) data;
3438 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u\n", fc, fc->queue_n);
3439 LOG (GNUNET_ERROR_TYPE_DEBUG, "last pid sent %u\n", fc->last_pid_sent);
3440 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack recv %u\n", fc->last_ack_recv);
3441 if (GNUNET_YES == droppable)
3447 LOG (GNUNET_ERROR_TYPE_DEBUG, " not droppable, Q_N stays the same\n");
3451 case GNUNET_MESSAGE_TYPE_CADET_KX:
3452 kmsg = (struct GNUNET_CADET_KX *) data;
3456 case GNUNET_MESSAGE_TYPE_CADET_ACK:
3457 amsg = (struct GNUNET_CADET_ACK *) data;
3459 LOG (GNUNET_ERROR_TYPE_DEBUG, " ack %u\n", ntohl (amsg->ack));
3460 droppable = GNUNET_NO;
3463 case GNUNET_MESSAGE_TYPE_CADET_POLL:
3464 pmsg = (struct GNUNET_CADET_Poll *) data;
3466 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL %u\n", ntohl (pmsg->pid));
3467 droppable = GNUNET_NO;
3470 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
3471 dmsg = (struct GNUNET_CADET_ConnectionDestroy *) data;
3475 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
3476 bmsg = (struct GNUNET_CADET_ConnectionBroken *) data;
3480 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
3481 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
3490 if (fc->queue_n > fc->queue_max && droppable)
3492 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
3495 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue full: %u/%u\n",
3496 fc->queue_n, fc->queue_max);
3497 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type
3498 || GNUNET_MESSAGE_TYPE_CADET_AX == type)
3503 return NULL; /* Drop this message */
3506 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %s %u\n",
3507 GCC_2s (c), c->pending_messages);
3508 c->pending_messages++;
3510 q = GNUNET_new (struct CadetConnectionQueue);
3511 q->forced = !droppable;
3512 q->q = GCP_queue_add (get_hop (c, fwd), data, type, payload_type, payload_id,
3513 size, c, fwd, &conn_message_sent, q);
3516 LOG (GNUNET_ERROR_TYPE_DEBUG, "dropping msg on %s, NULL q\n", GCC_2s (c));
3519 GCC_check_connections ();
3523 q->cont_cls = cont_cls;
3524 GCC_check_connections ();
3525 return (NULL == cont) ? NULL : q;
3530 * Cancel a previously sent message while it's in the queue.
3532 * ONLY can be called before the continuation given to the send function
3533 * is called. Once the continuation is called, the message is no longer in the
3536 * @param q Handle to the queue.
3539 GCC_cancel (struct CadetConnectionQueue *q)
3541 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GCC cancel message\n");
3543 /* queue destroy calls message_sent, which calls q->cont and frees q */
3544 GCP_queue_destroy (q->q, GNUNET_YES, GNUNET_NO, 0);
3545 GCC_check_connections ();
3550 * Sends a CREATE CONNECTION message for a path to a peer.
3551 * Changes the connection and tunnel states if necessary.
3553 * @param connection Connection to create.
3556 GCC_send_create (struct CadetConnection *connection)
3558 enum CadetTunnelCState state;
3561 GCC_check_connections ();
3562 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3563 size += connection->path->length * sizeof (struct GNUNET_PeerIdentity);
3565 LOG (GNUNET_ERROR_TYPE_INFO, "---> %s on connection %s (%u bytes)\n",
3566 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE),
3567 GCC_2s (connection), size);
3568 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3569 connection, connection->pending_messages);
3570 connection->pending_messages++;
3572 connection->maintenance_q =
3573 GCP_queue_add (get_next_hop (connection), NULL,
3574 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, 0, 0,
3575 size, connection, GNUNET_YES, &conn_message_sent, NULL);
3577 state = GCT_get_cstate (connection->t);
3578 if (CADET_TUNNEL_SEARCHING == state || CADET_TUNNEL_NEW == state)
3579 GCT_change_cstate (connection->t, CADET_TUNNEL_WAITING);
3580 if (CADET_CONNECTION_NEW == connection->state)
3581 connection_change_state (connection, CADET_CONNECTION_SENT);
3582 GCC_check_connections ();
3587 * Send a message to all peers in this connection that the connection
3588 * is no longer valid.
3590 * If some peer should not receive the message, it should be zero'ed out
3591 * before calling this function.
3593 * @param c The connection whose peers to notify.
3596 GCC_send_destroy (struct CadetConnection *c)
3598 struct GNUNET_CADET_ConnectionDestroy msg;
3600 if (GNUNET_YES == c->destroy)
3602 GCC_check_connections ();
3603 msg.header.size = htons (sizeof (msg));
3604 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
3606 LOG (GNUNET_ERROR_TYPE_DEBUG,
3607 " sending connection destroy for connection %s\n",
3610 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3611 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, 0, 0, c,
3612 GNUNET_YES, GNUNET_YES,
3614 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3615 GNUNET_assert (NULL == GCC_send_prebuilt_message (&msg.header, 0, 0, c,
3616 GNUNET_NO, GNUNET_YES,
3618 c->destroy = GNUNET_YES;
3619 c->state = CADET_CONNECTION_DESTROYED;
3620 GCC_check_connections ();
3625 * @brief Start a polling timer for the connection.
3627 * When a neighbor does not accept more traffic on the connection it could be
3628 * caused by a simple congestion or by a lost ACK. Polling enables to check
3629 * for the lastest ACK status for a connection.
3631 * @param c Connection.
3632 * @param fwd Should we poll in the FWD direction?
3635 GCC_start_poll (struct CadetConnection *c, int fwd)
3637 struct CadetFlowControl *fc;
3639 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3640 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL %s requested\n",
3642 if (NULL != fc->poll_task || NULL != fc->poll_msg)
3644 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL not needed (%p, %p)\n",
3645 fc->poll_task, fc->poll_msg);
3648 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL started on request\n");
3649 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
3656 * @brief Stop polling a connection for ACKs.
3658 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3660 * @param c Connection.
3661 * @param fwd Should we stop the poll in the FWD direction?
3664 GCC_stop_poll (struct CadetConnection *c, int fwd)
3666 struct CadetFlowControl *fc;
3668 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3669 if (NULL != fc->poll_task)
3671 GNUNET_SCHEDULER_cancel (fc->poll_task);
3672 fc->poll_task = NULL;
3678 * Get a (static) string for a connection.
3680 * @param c Connection.
3683 GCC_2s (const struct CadetConnection *c)
3690 static char buf[128];
3692 SPRINTF (buf, "%s (->%s)",
3693 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3696 return GNUNET_h2s (GC_h2hc (&c->id));
3701 * Log all possible info about the connection state.
3703 * @param c Connection to debug.
3704 * @param level Debug level to use.
3707 GCC_debug (const struct CadetConnection *c, enum GNUNET_ErrorType level)
3712 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
3714 __FILE__, __FUNCTION__, __LINE__);
3720 LOG2 (level, "CCC DEBUG NULL CONNECTION\n");
3724 LOG2 (level, "CCC DEBUG CONNECTION %s\n", GCC_2s (c));
3725 s = path_2s (c->path);
3726 LOG2 (level, "CCC path %s, own pos: %u\n", s, c->own_pos);
3728 LOG2 (level, "CCC state: %s, destroy: %u\n",
3729 GCC_state2s (c->state), c->destroy);
3730 LOG2 (level, "CCC pending messages: %u\n", c->pending_messages);
3731 if (NULL != c->perf)
3732 LOG2 (level, "CCC us/byte: %f\n", c->perf->avg);
3734 LOG2 (level, "CCC FWD flow control:\n");
3735 LOG2 (level, "CCC queue: %u/%u\n", c->fwd_fc.queue_n, c->fwd_fc.queue_max);
3736 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3737 c->fwd_fc.last_pid_sent, c->fwd_fc.last_pid_recv);
3738 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3739 c->fwd_fc.last_ack_sent, c->fwd_fc.last_ack_recv);
3740 LOG2 (level, "CCC recv PID bitmap: %X\n", c->fwd_fc.recv_bitmap);
3741 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3742 c->fwd_fc.poll_task, c->fwd_fc.poll_msg, c->fwd_fc.ack_msg);
3744 LOG2 (level, "CCC BCK flow control:\n");
3745 LOG2 (level, "CCC queue: %u/%u\n", c->bck_fc.queue_n, c->bck_fc.queue_max);
3746 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3747 c->bck_fc.last_pid_sent, c->bck_fc.last_pid_recv);
3748 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3749 c->bck_fc.last_ack_sent, c->bck_fc.last_ack_recv);
3750 LOG2 (level, "CCC recv PID bitmap: %X\n", c->bck_fc.recv_bitmap);
3751 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3752 c->bck_fc.poll_task, c->bck_fc.poll_msg, c->bck_fc.ack_msg);
3754 LOG2 (level, "CCC DEBUG CONNECTION END\n");