2 This file is part of GNUnet.
3 (C) 2013 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., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
23 #include "gnunet_util_lib.h"
25 #include "gnunet_statistics_service.h"
28 #include "mesh_protocol.h"
30 #include "gnunet-service-mesh_channel.h"
31 #include "gnunet-service-mesh_local.h"
32 #include "gnunet-service-mesh_tunnel.h"
33 #include "gnunet-service-mesh_peer.h"
35 #define LOG(level, ...) GNUNET_log_from(level,"mesh-chn",__VA_ARGS__)
37 #define MESH_RETRANSMIT_TIME GNUNET_TIME_UNIT_SECONDS
38 #define MESH_RETRANSMIT_MARGIN 4
42 * All the states a connection can be in.
47 * Uninitialized status, should never appear in operation.
52 * Connection create message sent, waiting for ACK.
57 * Connection confirmed, ready to carry traffic.
64 * Info holder for channel messages in queues.
66 struct MeshChannelQueue
71 struct MeshTunnel3Queue *q;
74 * Message type (DATA/DATA_ACK)
79 * Message copy (for DATAs, to start retransmission timer)
81 struct MeshReliableMessage *copy;
84 * Reliability (for DATA_ACKs, to access rel->ack_q)
86 struct MeshChannelReliability *rel;
91 * Info needed to retry a message in case it gets lost.
93 struct MeshReliableMessage
96 * Double linked list, FIFO style
98 struct MeshReliableMessage *next;
99 struct MeshReliableMessage *prev;
102 * Type of message (payload, channel management).
107 * Tunnel Reliability queue this message is in.
109 struct MeshChannelReliability *rel;
112 * ID of the message (ACK needed to free)
119 struct MeshTunnel3Queue *q;
122 * When was this message issued (to calculate ACK delay)
124 struct GNUNET_TIME_Absolute timestamp;
126 /* struct GNUNET_MESH_Data with payload */
131 * Info about the traffic state for a client in a channel.
133 struct MeshChannelReliability
136 * Channel this is about.
138 struct MeshChannel *ch;
141 * DLL of messages sent and not yet ACK'd.
143 struct MeshReliableMessage *head_sent;
144 struct MeshReliableMessage *tail_sent;
147 * DLL of messages received out of order.
149 struct MeshReliableMessage *head_recv;
150 struct MeshReliableMessage *tail_recv;
158 * Next MID to use for outgoing traffic.
163 * Next MID expected for incoming traffic.
168 * Handle for queued DATA_ACKs.
170 struct MeshChannelQueue *ack_q;
173 * Can we send data to the client?
178 * Can the client send data to us?
183 * Task to resend/poll in case no ACK is received.
185 GNUNET_SCHEDULER_TaskIdentifier retry_task;
188 * Counter for exponential backoff.
190 struct GNUNET_TIME_Relative retry_timer;
193 * How long does it usually take to get an ACK.
195 struct GNUNET_TIME_Relative expected_delay;
200 * Struct containing all information regarding a channel to a remote client.
205 * Tunnel this channel is in.
207 struct MeshTunnel3 *t;
210 * Destination port of the channel.
215 * Global channel number ( < GNUNET_MESH_LOCAL_CHANNEL_ID_CLI)
217 MESH_ChannelNumber gid;
220 * Local tunnel number for root (owner) client.
221 * ( >= GNUNET_MESH_LOCAL_CHANNEL_ID_CLI or 0 )
223 MESH_ChannelNumber lid_root;
226 * Local tunnel number for local destination clients (incoming number)
227 * ( >= GNUNET_MESH_LOCAL_CHANNEL_ID_SERV or 0).
229 MESH_ChannelNumber lid_dest;
234 enum MeshChannelState state;
237 * Is the tunnel bufferless (minimum latency)?
242 * Is the tunnel reliable?
247 * Last time the channel was used
249 struct GNUNET_TIME_Absolute timestamp;
252 * Client owner of the tunnel, if any
254 struct MeshClient *root;
257 * Client destination of the tunnel, if any.
259 struct MeshClient *dest;
262 * Flag to signal the destruction of the channel.
263 * If this is set GNUNET_YES the channel will be destroyed
264 * when the queue is empty.
269 * Total messages pending for this channel, payload or not.
271 unsigned int pending_messages;
275 * Only present (non-NULL) at the owner of a tunnel.
277 struct MeshChannelReliability *root_rel;
281 * Only present (non-NULL) at the destination of a tunnel.
283 struct MeshChannelReliability *dest_rel;
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 /******************************************************************************/
304 /******************************** STATIC ***********************************/
305 /******************************************************************************/
308 * Destroy a reliable message after it has been acknowledged, either by
309 * direct mid ACK or bitfield. Updates the appropriate data structures and
310 * timers and frees all memory.
312 * @param copy Message that is no longer needed: remote peer got it.
313 * @param update_time Is the timing information relevant?
314 * If this message is ACK in a batch the timing information
315 * is skewed by the retransmission, count only for the
316 * retransmitted message.
319 rel_message_free (struct MeshReliableMessage *copy, int update_time);
322 * We have received a message out of order, or the client is not ready.
323 * Buffer it until we receive an ACK from the client or the missing
324 * message from the channel.
326 * @param msg Message to buffer (MUST be of type MESH_DATA).
327 * @param rel Reliability data to the corresponding direction.
330 add_buffered_data (const struct GNUNET_MESH_Data *msg,
331 struct MeshChannelReliability *rel)
333 struct MeshReliableMessage *copy;
334 struct MeshReliableMessage *prev;
338 size = ntohs (msg->header.size);
339 mid = ntohl (msg->mid);
341 LOG (GNUNET_ERROR_TYPE_DEBUG, "add_buffered_data %u\n", mid);
343 copy = GNUNET_malloc (sizeof (*copy) + size);
346 copy->type = GNUNET_MESSAGE_TYPE_MESH_DATA;
347 memcpy (©[1], msg, size);
351 // FIXME do something better than O(n), although n < 64...
352 // FIXME start from the end (most messages are the latest ones)
353 for (prev = rel->head_recv; NULL != prev; prev = prev->next)
355 LOG (GNUNET_ERROR_TYPE_DEBUG, " prev %u\n", prev->mid);
356 if (GM_is_pid_bigger (prev->mid, mid))
358 LOG (GNUNET_ERROR_TYPE_DEBUG, " bingo!\n");
359 GNUNET_CONTAINER_DLL_insert_before (rel->head_recv, rel->tail_recv,
364 LOG (GNUNET_ERROR_TYPE_DEBUG, " insert at tail!\n");
365 GNUNET_CONTAINER_DLL_insert_tail (rel->head_recv, rel->tail_recv, copy);
366 LOG (GNUNET_ERROR_TYPE_DEBUG, "add_buffered_data END\n");
370 * Add a destination client to a channel, initializing all data structures
371 * in the channel and the client.
373 * @param ch Channel to which add the destination.
374 * @param c Client which to add to the channel.
377 add_destination (struct MeshChannel *ch, struct MeshClient *c)
379 if (NULL != ch->dest)
385 /* Assign local id as destination */
386 ch->lid_dest = GML_get_next_chid (c);
388 /* Store in client's hashmap */
389 GML_channel_add (c, ch->lid_dest, ch);
391 GNUNET_break (NULL == ch->dest_rel);
392 ch->dest_rel = GNUNET_new (struct MeshChannelReliability);
393 ch->dest_rel->ch = ch;
394 ch->dest_rel->expected_delay = MESH_RETRANSMIT_TIME;
401 * Send data to a client.
403 * If the client is ready, send directly, otherwise buffer while listening
407 * @param msg Message.
408 * @param fwd Is this a fwd (root->dest) message?
411 send_client_data (struct MeshChannel *ch,
412 const struct GNUNET_MESH_Data *msg,
417 if (ch->dest_rel->client_ready)
418 GML_send_data (ch->dest, msg, ch->lid_dest);
420 add_buffered_data (msg, ch->dest_rel);
424 if (ch->root_rel->client_ready)
425 GML_send_data (ch->root, msg, ch->lid_root);
427 add_buffered_data (msg, ch->root_rel);
433 * Send a buffered message to the client, for in order delivery or
434 * as result of client ACK.
436 * @param ch Channel on which to empty the message buffer.
437 * @param c Client to send to.
438 * @param fwd Is this to send FWD data?.
441 send_client_buffered_data (struct MeshChannel *ch,
442 struct MeshClient *c,
445 struct MeshReliableMessage *copy;
446 struct MeshChannelReliability *rel;
448 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_buffered_data\n");
449 rel = fwd ? ch->dest_rel : ch->root_rel;
450 if (GNUNET_NO == rel->client_ready)
452 LOG (GNUNET_ERROR_TYPE_DEBUG, "client not ready\n");
456 copy = rel->head_recv;
457 /* We never buffer channel management messages */
460 if (copy->mid == rel->mid_recv || GNUNET_NO == ch->reliable)
462 struct GNUNET_MESH_Data *msg = (struct GNUNET_MESH_Data *) ©[1];
464 LOG (GNUNET_ERROR_TYPE_DEBUG,
465 " have %u! now expecting %u\n",
466 copy->mid, rel->mid_recv + 1);
467 send_client_data (ch, msg, fwd);
470 GNUNET_CONTAINER_DLL_remove (rel->head_recv, rel->tail_recv, copy);
475 LOG (GNUNET_ERROR_TYPE_DEBUG,
476 " reliable && don't have %u, next is %u\n",
482 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_buffered_data END\n");
487 * Allow a client to send more data.
489 * In case the client was already allowed to send data, do nothing.
492 * @param fwd Is this a FWD ACK? (FWD ACKs are sent to root)
495 send_client_ack (struct MeshChannel *ch, int fwd)
497 struct MeshChannelReliability *rel = fwd ? ch->root_rel : ch->dest_rel;
499 LOG (GNUNET_ERROR_TYPE_DEBUG,
500 " sending %s ack to client on channel %s\n",
501 GM_f2s (fwd), GMCH_2s (ch));
509 if (GNUNET_YES == rel->client_allowed)
511 LOG (GNUNET_ERROR_TYPE_DEBUG, " already allowed\n");
514 rel->client_allowed = GNUNET_YES;
516 GML_send_ack (fwd ? ch->root : ch->dest, fwd ? ch->lid_root : ch->lid_dest);
521 * Notify the root that the destination rejected the channel.
523 * @param ch Rejected channel.
526 send_client_nack (struct MeshChannel *ch)
528 if (NULL == ch->root)
533 GML_send_nack (ch->root, ch->lid_root);
538 * Notify a client that the channel is no longer valid.
540 * @param ch Channel that is destroyed.
541 * @param local_only Should we try to send it to other peers?
544 send_destroy (struct MeshChannel *ch, int local_only)
546 struct GNUNET_MESH_ChannelManage msg;
548 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY);
549 msg.header.size = htons (sizeof (msg));
550 msg.chid = htonl (ch->gid);
552 /* If root is not NULL, notify.
553 * If it's NULL, check lid_root. When a local destroy comes in, root
554 * is set to NULL but lid_root is left untouched. In this case, do nothing,
555 * the client is the one who reuqested the channel to be destroyed.
557 if (NULL != ch->root)
558 GML_send_channel_destroy (ch->root, ch->lid_root);
559 else if (0 == ch->lid_root && GNUNET_NO == local_only)
560 GMCH_send_prebuilt_message (&msg.header, ch, GNUNET_NO, GNUNET_NO);
562 if (NULL != ch->dest)
563 GML_send_channel_destroy (ch->dest, ch->lid_dest);
564 else if (0 == ch->lid_dest && GNUNET_NO == local_only)
565 GMCH_send_prebuilt_message (&msg.header, ch, GNUNET_YES, GNUNET_NO);
570 * Destroy all reliable messages queued for a channel,
571 * during a channel destruction.
572 * Frees the reliability structure itself.
574 * @param rel Reliability data for a channel.
577 channel_rel_free_all (struct MeshChannelReliability *rel)
579 struct MeshReliableMessage *copy;
580 struct MeshReliableMessage *next;
585 for (copy = rel->head_recv; NULL != copy; copy = next)
588 GNUNET_CONTAINER_DLL_remove (rel->head_recv, rel->tail_recv, copy);
591 for (copy = rel->head_sent; NULL != copy; copy = next)
594 GNUNET_CONTAINER_DLL_remove (rel->head_sent, rel->tail_sent, copy);
597 if (GNUNET_SCHEDULER_NO_TASK != rel->retry_task)
598 GNUNET_SCHEDULER_cancel (rel->retry_task);
604 * Mark future messages as ACK'd.
606 * @param rel Reliability data.
607 * @param msg DataACK message with a bitfield of future ACK'd messages.
610 channel_rel_free_sent (struct MeshChannelReliability *rel,
611 const struct GNUNET_MESH_DataACK *msg)
613 struct MeshReliableMessage *copy;
614 struct MeshReliableMessage *next;
621 bitfield = msg->futures;
622 mid = ntohl (msg->mid);
623 LOG (GNUNET_ERROR_TYPE_DEBUG,
624 "!!! free_sent_reliable %u %llX\n",
626 LOG (GNUNET_ERROR_TYPE_DEBUG,
627 " rel %p, head %p\n",
628 rel, rel->head_sent);
629 for (i = 0, copy = rel->head_sent;
630 i < 64 && NULL != copy && 0 != bitfield;
633 LOG (GNUNET_ERROR_TYPE_DEBUG,
634 " trying bit %u (mid %u)\n",
637 if (0 == (bitfield & mask))
640 LOG (GNUNET_ERROR_TYPE_DEBUG, " set!\n");
641 /* Bit was set, clear the bit from the bitfield */
644 /* The i-th bit was set. Do we have that copy? */
645 /* Skip copies with mid < target */
646 target = mid + i + 1;
647 LOG (GNUNET_ERROR_TYPE_DEBUG, " target %u\n", target);
648 while (NULL != copy && GM_is_pid_bigger (target, copy->mid))
651 /* Did we run out of copies? (previously freed, it's ok) */
654 LOG (GNUNET_ERROR_TYPE_DEBUG, "run out of copies...\n");
658 /* Did we overshoot the target? (previously freed, it's ok) */
659 if (GM_is_pid_bigger (copy->mid, target))
661 LOG (GNUNET_ERROR_TYPE_DEBUG, " next copy %u\n", copy->mid);
665 /* Now copy->mid == target, free it */
667 rel_message_free (copy, GNUNET_YES);
670 LOG (GNUNET_ERROR_TYPE_DEBUG, "free_sent_reliable END\n");
675 * We haven't received an ACK after a certain time: restransmit the message.
677 * @param cls Closure (MeshReliableMessage with the message to restransmit)
678 * @param tc TaskContext.
681 channel_retransmit_message (void *cls,
682 const struct GNUNET_SCHEDULER_TaskContext *tc)
684 struct MeshChannelReliability *rel = cls;
685 struct MeshReliableMessage *copy;
686 struct MeshChannel *ch;
687 struct GNUNET_MESH_Data *payload;
690 rel->retry_task = GNUNET_SCHEDULER_NO_TASK;
691 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
695 copy = rel->head_sent;
702 payload = (struct GNUNET_MESH_Data *) ©[1];
703 fwd = (rel == ch->root_rel);
705 /* Message not found in the queue that we are going to use. */
706 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! RETRANSMIT %u\n", copy->mid);
708 GMCH_send_prebuilt_message (&payload->header, ch, fwd, GNUNET_YES);
709 GNUNET_STATISTICS_update (stats, "# data retransmitted", 1, GNUNET_NO);
711 copy->timestamp = GNUNET_TIME_absolute_get();
712 rel->retry_timer = GNUNET_TIME_STD_BACKOFF (rel->retry_timer);
713 rel->retry_task = GNUNET_SCHEDULER_add_delayed (rel->retry_timer,
714 &channel_retransmit_message,
720 * Destroy a reliable message after it has been acknowledged, either by
721 * direct mid ACK or bitfield. Updates the appropriate data structures and
722 * timers and frees all memory.
724 * @param copy Message that is no longer needed: remote peer got it.
725 * @param update_time Is the timing information relevant?
726 * If this message is ACK in a batch the timing information
727 * is skewed by the retransmission, count only for the
728 * retransmitted message.
731 rel_message_free (struct MeshReliableMessage *copy, int update_time)
733 struct MeshChannelReliability *rel;
734 struct GNUNET_TIME_Relative time;
737 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! Freeing %u\n", copy->mid);
740 time = GNUNET_TIME_absolute_get_duration (copy->timestamp);
741 rel->expected_delay.rel_value_us *= 7;
742 rel->expected_delay.rel_value_us += time.rel_value_us;
743 rel->expected_delay.rel_value_us /= 8;
744 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! took %s\n",
745 GNUNET_STRINGS_relative_time_to_string (time, GNUNET_NO));
746 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! new expected delay %s\n",
747 GNUNET_STRINGS_relative_time_to_string (rel->expected_delay,
749 rel->retry_timer = rel->expected_delay;
753 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! batch free, ignoring timing\n");
755 GNUNET_CONTAINER_DLL_remove (rel->head_sent, rel->tail_sent, copy);
761 * Confirm we got a channel create.
763 * @param ch The channel to confirm.
764 * @param fwd Should we send a FWD ACK? (going dest->root)
767 channel_send_ack (struct MeshChannel *ch, int fwd)
769 struct GNUNET_MESH_ChannelManage msg;
771 msg.header.size = htons (sizeof (msg));
772 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK);
773 LOG (GNUNET_ERROR_TYPE_DEBUG,
774 " sending channel %s ack for channel %s\n",
775 GM_f2s (fwd), GMCH_2s (ch));
777 msg.chid = htonl (ch->gid);
778 GMCH_send_prebuilt_message (&msg.header, ch, !fwd, GNUNET_NO);
783 * Notify that a channel create didn't succeed.
785 * @param ch The channel to reject.
788 channel_send_nack (struct MeshChannel *ch)
790 struct GNUNET_MESH_ChannelManage msg;
792 msg.header.size = htons (sizeof (msg));
793 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK);
794 LOG (GNUNET_ERROR_TYPE_DEBUG,
795 " sending channel NACK for channel %s\n",
798 msg.chid = htonl (ch->gid);
799 GMCH_send_prebuilt_message (&msg.header, ch, GNUNET_NO, GNUNET_NO);
804 * Channel was ACK'd by remote peer, mark as ready and cancel retransmission.
806 * @param ch Channel to mark as ready.
807 * @param fwd Was the ACK message a FWD ACK? (dest->root, SYNACK)
810 channel_confirm (struct MeshChannel *ch, int fwd)
812 struct MeshChannelReliability *rel;
813 struct MeshReliableMessage *copy;
814 struct MeshReliableMessage *next;
816 LOG (GNUNET_ERROR_TYPE_DEBUG,
817 " channel confirm %s %s:%X\n",
818 GM_f2s (fwd), GMT_2s (ch->t), ch->gid);
819 ch->state = MESH_CHANNEL_READY;
821 rel = fwd ? ch->root_rel : ch->dest_rel;
822 rel->client_ready = GNUNET_YES;
823 for (copy = rel->head_sent; NULL != copy; copy = next)
825 struct GNUNET_MessageHeader *msg;
828 msg = (struct GNUNET_MessageHeader *) ©[1];
829 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE)
831 rel_message_free (copy, GNUNET_YES);
835 send_client_ack (ch, fwd);
837 /* In case of a FWD ACK (SYNACK) send a BCK ACK (ACK). */
839 channel_send_ack (ch, !fwd);
844 * Message has been sent: start retransmission timer.
846 * @param cls Closure (queue structure).
848 * @param q Queue handler (no longer valid).
849 * @param type Type of message.
850 * @param size Size of the message.
853 ch_message_sent (void *cls,
854 struct MeshTunnel3 *t,
855 struct MeshTunnel3Queue *q,
856 uint16_t type, size_t size)
858 struct MeshChannelQueue *ch_q = cls;
859 struct MeshReliableMessage *copy = ch_q->copy;
860 struct MeshChannelReliability *rel;
864 case GNUNET_MESSAGE_TYPE_MESH_DATA:
865 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! SENT %u %s\n",
866 copy->mid, GM_m2s (type));
867 copy->timestamp = GNUNET_TIME_absolute_get ();
869 if (GNUNET_SCHEDULER_NO_TASK == rel->retry_task)
872 GNUNET_TIME_relative_multiply (rel->expected_delay,
873 MESH_RETRANSMIT_MARGIN);
875 GNUNET_SCHEDULER_add_delayed (rel->retry_timer,
876 &channel_retransmit_message,
882 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
884 GNUNET_assert (rel->ack_q == ch_q);
898 * Save a copy to retransmit in case it gets lost.
900 * Initializes all needed callbacks and timers.
902 * @param ch Channel this message goes on.
903 * @param msg Message to copy.
904 * @param fwd Is this fwd traffic?
906 static struct MeshReliableMessage *
907 channel_save_copy (struct MeshChannel *ch,
908 const struct GNUNET_MessageHeader *msg,
911 struct MeshChannelReliability *rel;
912 struct MeshReliableMessage *copy;
917 rel = fwd ? ch->root_rel : ch->dest_rel;
918 mid = rel->mid_send - 1;
919 type = ntohs (msg->type);
920 size = ntohs (msg->size);
922 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! SAVE %u %s\n", mid, GM_m2s (type));
923 copy = GNUNET_malloc (sizeof (struct MeshReliableMessage) + size);
927 memcpy (©[1], msg, size);
928 GNUNET_CONTAINER_DLL_insert_tail (rel->head_sent, rel->tail_sent, copy);
935 * Create a new channel.
937 * @param t Tunnel this channel is in.
938 * @param owner Client that owns the channel, NULL for foreign channels.
939 * @param lid_root Local ID for root client.
941 * @return A new initialized channel. NULL on error.
943 static struct MeshChannel *
944 channel_new (struct MeshTunnel3 *t,
945 struct MeshClient *owner,
946 MESH_ChannelNumber lid_root)
948 struct MeshChannel *ch;
950 ch = GNUNET_new (struct MeshChannel);
952 ch->lid_root = lid_root;
955 GNUNET_STATISTICS_update (stats, "# channels", 1, GNUNET_NO);
959 ch->gid = GMT_get_next_chid (t);
960 GML_channel_add (owner, lid_root, ch);
962 GMT_add_channel (t, ch);
969 * Set options in a channel, extracted from a bit flag field
971 * @param ch Channel to set options to.
972 * @param options Bit array in host byte order.
975 channel_set_options (struct MeshChannel *ch, uint32_t options)
977 ch->nobuffer = (options & GNUNET_MESH_OPTION_NOBUFFER) != 0 ?
978 GNUNET_YES : GNUNET_NO;
979 ch->reliable = (options & GNUNET_MESH_OPTION_RELIABLE) != 0 ?
980 GNUNET_YES : GNUNET_NO;
984 is_loopback (const struct MeshChannel *ch)
987 return GMT_is_loopback (ch->t);
989 return (NULL != ch->root && NULL != ch->dest);
994 * Handle a loopback message: call the appropriate handler for the message type.
996 * @param ch Channel this message is on.
997 * @param msgh Message header.
998 * @param fwd Is this FWD traffic?
1001 handle_loopback (struct MeshChannel *ch,
1002 const struct GNUNET_MessageHeader *msgh,
1007 type = ntohs (msgh->type);
1008 LOG (GNUNET_ERROR_TYPE_DEBUG,
1009 "Loopback %s %s message!\n",
1010 GM_f2s (fwd), GM_m2s (type));
1014 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1015 /* Don't send hop ACK, wait for client to ACK */
1016 GMCH_handle_data (ch, (struct GNUNET_MESH_Data *) msgh, fwd);
1019 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1020 GMCH_handle_data_ack (ch, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1023 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1024 GMCH_handle_create (ch->t,
1025 (struct GNUNET_MESH_ChannelCreate *) msgh);
1028 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1029 GMCH_handle_ack (ch,
1030 (struct GNUNET_MESH_ChannelManage *) msgh,
1034 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1035 GMCH_handle_nack (ch);
1038 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1039 GMCH_handle_destroy (ch,
1040 (struct GNUNET_MESH_ChannelManage *) msgh,
1045 GNUNET_break_op (0);
1046 LOG (GNUNET_ERROR_TYPE_DEBUG,
1047 "end-to-end message not known (%u)\n",
1048 ntohs (msgh->type));
1054 /******************************************************************************/
1055 /******************************** API ***********************************/
1056 /******************************************************************************/
1059 * Destroy a channel and free all resources.
1061 * @param ch Channel to destroy.
1064 GMCH_destroy (struct MeshChannel *ch)
1066 struct MeshClient *c;
1071 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying channel %s:%u\n",
1072 GMT_2s (ch->t), ch->gid);
1078 GML_channel_remove (c, ch->lid_root, ch);
1084 GML_channel_remove (c, ch->lid_dest, ch);
1087 channel_rel_free_all (ch->root_rel);
1088 channel_rel_free_all (ch->dest_rel);
1090 GMT_remove_channel (ch->t, ch);
1091 GNUNET_STATISTICS_update (stats, "# channels", -1, GNUNET_NO);
1100 * @param ch Channel.
1105 GMCH_get_id (const struct MeshChannel *ch)
1112 * Get the channel tunnel.
1114 * @param ch Channel to get the tunnel from.
1116 * @return tunnel of the channel.
1118 struct MeshTunnel3 *
1119 GMCH_get_tunnel (const struct MeshChannel *ch)
1126 * Get free buffer space towards the client on a specific channel.
1128 * @param ch Channel.
1129 * @param fwd Is query about FWD traffic?
1131 * @return Free buffer space [0 - 64]
1134 GMCH_get_buffer (struct MeshChannel *ch, int fwd)
1136 struct MeshChannelReliability *rel;
1138 rel = fwd ? ch->dest_rel : ch->root_rel;
1140 /* If rel is NULL it means that the end is not yet created,
1141 * most probably is a loopback channel at the point of sending
1142 * the ChannelCreate to itself.
1147 return (64 - rel->n_recv);
1152 * Get flow control status of end point: is client allow to send?
1154 * @param ch Channel.
1155 * @param fwd Is query about FWD traffic? (Request root status).
1157 * @return #GNUNET_YES if client is allowed to send us data.
1160 GMCH_get_allowed (struct MeshChannel *ch, int fwd)
1162 struct MeshChannelReliability *rel;
1164 rel = fwd ? ch->root_rel : ch->dest_rel;
1166 return rel->client_allowed;
1171 * Is the root client for this channel on this peer?
1173 * @param ch Channel.
1174 * @param fwd Is this for fwd traffic?
1176 * @return #GNUNET_YES in case it is.
1179 GMCH_is_origin (struct MeshChannel *ch, int fwd)
1181 struct MeshClient *c;
1183 c = fwd ? ch->root : ch->dest;
1189 * Is the destination client for this channel on this peer?
1191 * @param ch Channel.
1192 * @param fwd Is this for fwd traffic?
1194 * @return #GNUNET_YES in case it is.
1197 GMCH_is_terminal (struct MeshChannel *ch, int fwd)
1199 struct MeshClient *c;
1201 c = fwd ? ch->dest : ch->root;
1207 * Notify the destination client that a new incoming channel was created.
1209 * @param ch Channel that was created.
1212 GMCH_send_create (struct MeshChannel *ch)
1216 if (NULL == ch->dest)
1220 opt |= GNUNET_YES == ch->reliable ? GNUNET_MESH_OPTION_RELIABLE : 0;
1221 opt |= GNUNET_YES == ch->nobuffer ? GNUNET_MESH_OPTION_NOBUFFER : 0;
1222 GML_send_channel_create (ch->dest, ch->lid_dest, ch->port, opt,
1223 GMT_get_destination (ch->t));
1229 * Send an end-to-end ACK message for the most recent in-sequence payload.
1231 * If channel is not reliable, do nothing.
1233 * @param ch Channel this is about.
1234 * @param fwd Is for FWD traffic? (ACK dest->owner)
1237 GMCH_send_data_ack (struct MeshChannel *ch, int fwd)
1239 struct GNUNET_MESH_DataACK msg;
1240 struct MeshChannelReliability *rel;
1241 struct MeshReliableMessage *copy;
1246 if (GNUNET_NO == ch->reliable)
1250 rel = fwd ? ch->dest_rel : ch->root_rel;
1251 ack = rel->mid_recv - 1;
1252 LOG (GNUNET_ERROR_TYPE_DEBUG,
1253 " !! Send DATA_ACK for %u\n",
1256 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_DATA_ACK);
1257 msg.header.size = htons (sizeof (msg));
1258 msg.chid = htonl (ch->gid);
1260 for (copy = rel->head_recv; NULL != copy; copy = copy->next)
1262 if (copy->type != GNUNET_MESSAGE_TYPE_MESH_DATA)
1264 LOG (GNUNET_ERROR_TYPE_DEBUG,
1265 "!! Type %s, expected DATA\n",
1266 GM_m2s (copy->type));
1269 if (copy->mid == ack + 1)
1274 delta = copy->mid - (ack + 1);
1277 mask = 0x1LL << delta;
1278 msg.futures |= mask;
1279 LOG (GNUNET_ERROR_TYPE_DEBUG,
1280 " !! setting bit for %u (delta %u) (%llX) -> %llX\n",
1281 copy->mid, delta, mask, msg.futures);
1283 msg.mid = htonl (ack);
1284 LOG (GNUNET_ERROR_TYPE_DEBUG,
1285 "!!! ACK for %u, futures %llX\n",
1288 GMCH_send_prebuilt_message (&msg.header, ch, !fwd, GNUNET_NO);
1289 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_data_ack END\n");
1294 * Allow a client to send us more data, in case it was choked.
1296 * @param ch Channel.
1297 * @param fwd Is this about FWD traffic? (Root client).
1300 GMCH_allow_client (struct MeshChannel *ch, int fwd)
1302 struct MeshChannelReliability *rel;
1303 unsigned int buffer;
1305 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMCH allow\n");
1307 if (MESH_CHANNEL_READY != ch->state)
1309 LOG (GNUNET_ERROR_TYPE_DEBUG, " channel not ready yet!\n");
1313 if (GNUNET_YES == ch->reliable)
1315 rel = fwd ? ch->root_rel : ch->dest_rel;
1321 if (NULL != rel->head_sent && 64 <= rel->mid_send - rel->head_sent->mid)
1323 LOG (GNUNET_ERROR_TYPE_DEBUG, " too big MID gap! Wait for ACK.\n");
1328 if (is_loopback (ch))
1329 buffer = GMCH_get_buffer (ch, fwd);
1331 buffer = GMT_get_connections_buffer (ch->t);
1335 LOG (GNUNET_ERROR_TYPE_DEBUG, " no buffer space.\n");
1339 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space %u, allowing\n", buffer);
1340 send_client_ack (ch, fwd);
1347 * @param ch Channel.
1350 GMCH_debug (struct MeshChannel *ch)
1354 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CHANNEL ***\n");
1357 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %s:%X (%p)\n",
1358 GMT_2s (ch->t), ch->gid, ch);
1359 LOG (GNUNET_ERROR_TYPE_DEBUG, " root %p/%p\n",
1360 ch->root, ch->root_rel);
1361 if (NULL != ch->root)
1363 LOG (GNUNET_ERROR_TYPE_DEBUG, " cli %s\n", GML_2s (ch->root));
1364 LOG (GNUNET_ERROR_TYPE_DEBUG, " ready %s\n",
1365 ch->root_rel->client_ready ? "YES" : "NO");
1366 LOG (GNUNET_ERROR_TYPE_DEBUG, " id %X\n", ch->lid_root);
1368 LOG (GNUNET_ERROR_TYPE_DEBUG, " dest %p/%p\n",
1369 ch->dest, ch->dest_rel);
1370 if (NULL != ch->dest)
1372 LOG (GNUNET_ERROR_TYPE_DEBUG, " cli %s\n", GML_2s (ch->dest));
1373 LOG (GNUNET_ERROR_TYPE_DEBUG, " ready %s\n",
1374 ch->dest_rel->client_ready ? "YES" : "NO");
1375 LOG (GNUNET_ERROR_TYPE_DEBUG, " id %X\n", ch->lid_dest);
1381 * Handle an ACK given by a client.
1383 * Mark client as ready and send him any buffered data we could have for him.
1385 * @param ch Channel.
1386 * @param fwd Is this a "FWD ACK"? (FWD ACKs are sent by dest and go BCK)
1389 GMCH_handle_local_ack (struct MeshChannel *ch, int fwd)
1391 struct MeshChannelReliability *rel;
1392 struct MeshClient *c;
1394 rel = fwd ? ch->dest_rel : ch->root_rel;
1395 c = fwd ? ch->dest : ch->root;
1397 rel->client_ready = GNUNET_YES;
1398 send_client_buffered_data (ch, c, fwd);
1399 if (is_loopback (ch))
1401 unsigned int buffer;
1403 buffer = GMCH_get_buffer (ch, fwd);
1405 GMCH_allow_client (ch, fwd);
1409 GMT_send_connection_acks (ch->t);
1414 * Handle data given by a client.
1416 * Check whether the client is allowed to send in this tunnel, save if channel
1417 * is reliable and send an ACK to the client if there is still buffer space
1420 * @param ch Channel.
1421 * @param c Client which sent the data.
1422 * @param message Message.
1423 * @param fwd Is this a FWD data?
1425 * @return GNUNET_OK if everything goes well, GNUNET_SYSERR in case of en error.
1428 GMCH_handle_local_data (struct MeshChannel *ch,
1429 struct MeshClient *c,
1430 struct GNUNET_MessageHeader *message,
1433 struct MeshChannelReliability *rel;
1434 struct GNUNET_MESH_Data *payload;
1435 size_t size = ntohs (message->size);
1436 uint16_t p2p_size = sizeof(struct GNUNET_MESH_Data) + size;
1437 unsigned char cbuf[p2p_size];
1439 /* Is the client in the channel? */
1446 GNUNET_break_op (0);
1447 return GNUNET_SYSERR;
1450 rel = fwd ? ch->root_rel : ch->dest_rel;
1452 if (GNUNET_NO == rel->client_allowed)
1454 GNUNET_break_op (0);
1455 return GNUNET_SYSERR;
1458 rel->client_allowed = GNUNET_NO;
1460 /* Ok, everything is correct, send the message. */
1461 payload = (struct GNUNET_MESH_Data *) cbuf;
1462 payload->mid = htonl (rel->mid_send);
1464 memcpy (&payload[1], message, size);
1465 payload->header.size = htons (p2p_size);
1466 payload->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_DATA);
1467 payload->chid = htonl (ch->gid);
1468 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channel...\n");
1469 GMCH_send_prebuilt_message (&payload->header, ch, fwd, GNUNET_NO);
1471 if (is_loopback (ch))
1473 if (GMCH_get_buffer (ch, fwd) > 0)
1474 send_client_ack (ch, fwd);
1479 if (GMT_get_connections_buffer (ch->t) > 0)
1481 send_client_ack (ch, fwd);
1489 * Handle a channel destroy requested by a client.
1491 * Destroy the channel and the tunnel in case this was the last channel.
1493 * @param ch Channel.
1494 * @param c Client that requested the destruction (to avoid notifying him).
1495 * @param is_root Is the request coming from root?
1498 GMCH_handle_local_destroy (struct MeshChannel *ch,
1499 struct MeshClient *c,
1502 struct MeshTunnel3 *t;
1504 /* Cleanup after the tunnel */
1505 if (GNUNET_NO == is_root && c == ch->dest)
1507 LOG (GNUNET_ERROR_TYPE_DEBUG, " Client %s is destination.\n", GML_2s (c));
1508 GML_client_delete_channel (c, ch, ch->lid_dest);
1511 if (GNUNET_YES == is_root && c == ch->root)
1513 LOG (GNUNET_ERROR_TYPE_DEBUG, " Client %s is owner.\n", GML_2s (c));
1514 GML_client_delete_channel (c, ch, ch->lid_root);
1519 send_destroy (ch, GNUNET_NO);
1521 GMT_destroy_if_empty (t);
1526 * Handle a channel create requested by a client.
1528 * Create the channel and the tunnel in case this was the first0 channel.
1530 * @param c Client that requested the creation (will be the root).
1531 * @param msg Create Channel message.
1533 * @return GNUNET_OK if everything went fine, GNUNET_SYSERR otherwise.
1536 GMCH_handle_local_create (struct MeshClient *c,
1537 struct GNUNET_MESH_ChannelMessage *msg)
1539 struct MeshChannel *ch;
1540 struct MeshTunnel3 *t;
1541 struct MeshPeer *peer;
1542 MESH_ChannelNumber chid;
1544 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s:%u\n",
1545 GNUNET_i2s (&msg->peer), ntohl (msg->port));
1546 chid = ntohl (msg->channel_id);
1548 /* Sanity check for duplicate channel IDs */
1549 if (NULL != GML_channel_get (c, chid))
1552 return GNUNET_SYSERR;
1555 peer = GMP_get (&msg->peer);
1556 GMP_add_tunnel (peer);
1557 t = GMP_get_tunnel (peer);
1559 if (GMP_get_short_id (peer) == myid)
1561 GMT_change_cstate (t, MESH_TUNNEL3_READY);
1568 /* Create channel */
1569 ch = channel_new (t, c, chid);
1573 return GNUNET_SYSERR;
1575 ch->port = ntohl (msg->port);
1576 channel_set_options (ch, ntohl (msg->opt));
1578 /* In unreliable channels, we'll use the DLL to buffer BCK data */
1579 ch->root_rel = GNUNET_new (struct MeshChannelReliability);
1580 ch->root_rel->ch = ch;
1581 ch->root_rel->expected_delay = MESH_RETRANSMIT_TIME;
1583 LOG (GNUNET_ERROR_TYPE_DEBUG, "CREATED CHANNEL %s\n", GMCH_2s (ch));
1585 /* Send create channel */
1587 struct GNUNET_MESH_ChannelCreate msgcc;
1589 msgcc.header.size = htons (sizeof (msgcc));
1590 msgcc.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE);
1591 msgcc.chid = htonl (ch->gid);
1592 msgcc.port = msg->port;
1593 msgcc.opt = msg->opt;
1595 GMT_send_prebuilt_message (&msgcc.header, t, ch, GNUNET_YES, NULL, NULL);
1602 * Handler for mesh network payload traffic.
1604 * @param ch Channel for the message.
1605 * @param msg Unencryted data message.
1606 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1607 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1608 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1609 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1612 GMCH_handle_data (struct MeshChannel *ch,
1613 const struct GNUNET_MESH_Data *msg,
1616 struct MeshChannelReliability *rel;
1617 struct MeshClient *c;
1620 /* If this is a remote (non-loopback) channel, find 'fwd'. */
1621 if (GNUNET_SYSERR == fwd)
1623 if (is_loopback (ch))
1625 /* It is a loopback channel after all... */
1629 fwd = (NULL != ch->dest) ? GNUNET_YES : GNUNET_NO;
1632 /* Initialize FWD/BCK data */
1633 c = fwd ? ch->dest : ch->root;
1634 rel = fwd ? ch->dest_rel : ch->root_rel;
1642 GNUNET_STATISTICS_update (stats, "# data received", 1, GNUNET_NO);
1644 mid = ntohl (msg->mid);
1645 LOG (GNUNET_ERROR_TYPE_DEBUG, "!! got mid %u\n", mid);
1647 if (GNUNET_NO == ch->reliable ||
1648 ( !GM_is_pid_bigger (rel->mid_recv, mid) &&
1649 GM_is_pid_bigger (rel->mid_recv + 64, mid) ) )
1651 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! RECV %u\n", mid);
1652 if (GNUNET_YES == ch->reliable)
1654 /* Is this the exact next expected messasge? */
1655 if (mid == rel->mid_recv)
1657 LOG (GNUNET_ERROR_TYPE_DEBUG, "as expected\n");
1659 send_client_data (ch, msg, fwd);
1663 LOG (GNUNET_ERROR_TYPE_DEBUG, "save for later\n");
1664 add_buffered_data (msg, rel);
1669 /* Tunnel is unreliable: send to clients directly */
1670 /* FIXME: accept Out Of Order traffic */
1671 rel->mid_recv = mid + 1;
1672 send_client_data (ch, msg, fwd);
1677 GNUNET_break_op (0);
1678 LOG (GNUNET_ERROR_TYPE_DEBUG,
1679 " MID %u not expected (%u - %u), dropping!\n",
1680 mid, rel->mid_recv, rel->mid_recv + 63);
1683 GMCH_send_data_ack (ch, fwd);
1688 * Handler for mesh network traffic end-to-end ACKs.
1690 * @param ch Channel on which we got this message.
1691 * @param msg Data message.
1692 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1693 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1694 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1695 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1698 GMCH_handle_data_ack (struct MeshChannel *ch,
1699 const struct GNUNET_MESH_DataACK *msg,
1702 struct MeshChannelReliability *rel;
1703 struct MeshReliableMessage *copy;
1704 struct MeshReliableMessage *next;
1708 /* If this is a remote (non-loopback) channel, find 'fwd'. */
1709 if (GNUNET_SYSERR == fwd)
1711 if (is_loopback (ch))
1713 /* It is a loopback channel after all... */
1717 /* Inverted: if message came 'FWD' is a 'BCK ACK'. */
1718 fwd = (NULL != ch->dest) ? GNUNET_NO : GNUNET_YES;
1721 ack = ntohl (msg->mid);
1722 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! %s ACK %u\n",
1723 (GNUNET_YES == fwd) ? "FWD" : "BCK", ack);
1725 if (GNUNET_YES == fwd)
1735 GNUNET_break_op (0);
1739 /* Free ACK'd copies: no need to retransmit those anymore */
1740 for (work = GNUNET_NO, copy = rel->head_sent; copy != NULL; copy = next)
1742 if (GM_is_pid_bigger (copy->mid, ack))
1744 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! head %u, out!\n", copy->mid);
1745 channel_rel_free_sent (rel, msg);
1749 LOG (GNUNET_ERROR_TYPE_DEBUG, " !! id %u\n", copy->mid);
1751 rel_message_free (copy, GNUNET_YES);
1754 /* ACK client if needed */
1755 GMCH_allow_client (ch, fwd);
1757 /* If some message was free'd, update the retransmission delay */
1758 if (GNUNET_YES == work)
1760 if (GNUNET_SCHEDULER_NO_TASK != rel->retry_task)
1762 GNUNET_SCHEDULER_cancel (rel->retry_task);
1763 if (NULL == rel->head_sent)
1765 rel->retry_task = GNUNET_SCHEDULER_NO_TASK;
1769 struct GNUNET_TIME_Absolute new_target;
1770 struct GNUNET_TIME_Relative delay;
1772 delay = GNUNET_TIME_relative_multiply (rel->retry_timer,
1773 MESH_RETRANSMIT_MARGIN);
1774 new_target = GNUNET_TIME_absolute_add (rel->head_sent->timestamp,
1776 delay = GNUNET_TIME_absolute_get_remaining (new_target);
1778 GNUNET_SCHEDULER_add_delayed (delay,
1779 &channel_retransmit_message,
1790 * Handler for channel create messages.
1792 * Does not have fwd parameter because it's always 'FWD': channel is incoming.
1794 * @param t Tunnel this channel will be in.
1795 * @param msg Channel crate message.
1797 struct MeshChannel *
1798 GMCH_handle_create (struct MeshTunnel3 *t,
1799 const struct GNUNET_MESH_ChannelCreate *msg)
1801 MESH_ChannelNumber chid;
1802 struct MeshChannel *ch;
1803 struct MeshClient *c;
1805 chid = ntohl (msg->chid);
1807 ch = GMT_get_channel (t, chid);
1810 /* Create channel */
1811 ch = channel_new (t, NULL, 0);
1814 channel_set_options (ch, ntohl (msg->opt));
1816 /* Find a destination client */
1817 ch->port = ntohl (msg->port);
1818 LOG (GNUNET_ERROR_TYPE_DEBUG, " port %u\n", ch->port);
1819 c = GML_client_get_by_port (ch->port);
1822 /* TODO send reject */
1823 LOG (GNUNET_ERROR_TYPE_DEBUG, " no client has port registered\n");
1824 if (is_loopback (ch))
1826 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback: destroy on handler\n");
1827 channel_send_nack (ch);
1831 LOG (GNUNET_ERROR_TYPE_DEBUG, " not loopback: destroy now\n");
1832 channel_send_nack (ch);
1839 LOG (GNUNET_ERROR_TYPE_DEBUG, " client %p has port registered\n", c);
1842 add_destination (ch, c);
1843 if (GNUNET_YES == ch->reliable)
1844 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! Reliable\n");
1846 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! Not Reliable\n");
1848 GMCH_send_create (ch);
1849 channel_send_ack (ch, GNUNET_YES);
1856 * Handler for channel NACK messages.
1858 * NACK messages always go dest -> root, no need for 'fwd' or 'msg' parameter.
1860 * @param ch Channel.
1863 GMCH_handle_nack (struct MeshChannel *ch)
1865 send_client_nack (ch);
1871 * Handler for channel ack messages.
1873 * @param ch Channel.
1874 * @param msg Message.
1875 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1876 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1877 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1878 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1881 GMCH_handle_ack (struct MeshChannel *ch,
1882 const struct GNUNET_MESH_ChannelManage *msg,
1885 /* If this is a remote (non-loopback) channel, find 'fwd'. */
1886 if (GNUNET_SYSERR == fwd)
1888 if (is_loopback (ch))
1890 /* It is a loopback channel after all... */
1894 fwd = (NULL != ch->dest) ? GNUNET_YES : GNUNET_NO;
1897 channel_confirm (ch, !fwd);
1902 * Handler for channel destroy messages.
1904 * @param ch Channel to be destroyed of.
1905 * @param msg Message.
1906 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1907 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1908 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1909 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1912 GMCH_handle_destroy (struct MeshChannel *ch,
1913 const struct GNUNET_MESH_ChannelManage *msg,
1916 struct MeshTunnel3 *t;
1918 /* If this is a remote (non-loopback) channel, find 'fwd'. */
1919 if (GNUNET_SYSERR == fwd)
1921 if (is_loopback (ch))
1923 /* It is a loopback channel after all... */
1927 fwd = (NULL != ch->dest) ? GNUNET_YES : GNUNET_NO;
1931 if ( (fwd && NULL == ch->dest) || (!fwd && NULL == ch->root) )
1933 /* Not for us (don't destroy twice a half-open loopback channel) */
1938 send_destroy (ch, GNUNET_YES);
1940 GMT_destroy_if_empty (t);
1945 * Sends an already built message on a channel.
1947 * If the channel is on a loopback tunnel, notifies the appropriate destination
1950 * On a normal channel passes the message to the tunnel for encryption and
1951 * sending on a connection.
1953 * This function DOES NOT save the message for retransmission.
1955 * @param message Message to send. Function makes a copy of it.
1956 * @param ch Channel on which this message is transmitted.
1957 * @param fwd Is this a fwd message?
1958 * @param retransmission Is this a retransmission? (Don't save a copy)
1961 GMCH_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
1962 struct MeshChannel *ch, int fwd,
1967 type = ntohs (message->type);
1968 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMCH Send %s %s on channel %s\n",
1969 GM_f2s (fwd), GM_m2s (type),
1972 if (GMT_is_loopback (ch->t))
1974 handle_loopback (ch, message, fwd);
1978 if (GNUNET_YES == ch->reliable && GNUNET_NO == retransmission
1979 && GNUNET_MESSAGE_TYPE_MESH_DATA == type)
1981 struct MeshChannelQueue *q;
1983 q = GNUNET_new (struct MeshChannelQueue);
1985 q->copy = channel_save_copy (ch, message, fwd);
1986 q->q = GMT_send_prebuilt_message (message, ch->t, ch, fwd,
1987 &ch_message_sent, q);
1988 /* Don't store q itself: we never need to cancel messages */
1990 else if (GNUNET_MESSAGE_TYPE_MESH_DATA_ACK == type)
1992 struct MeshChannelReliability *rel;
1994 rel = fwd ? ch->root_rel : ch->dest_rel;
1995 if (NULL != rel->ack_q)
1997 GMT_cancel (rel->ack_q->q);
1998 /* ch_message_sent is called, freeing ack_q */
2000 rel->ack_q = GNUNET_new (struct MeshChannelQueue);
2001 rel->ack_q->type = type;
2002 rel->ack_q->rel = rel;
2003 rel->ack_q->q = GMT_send_prebuilt_message (message, ch->t, ch, fwd,
2004 &ch_message_sent, rel->ack_q);
2007 GNUNET_break (NULL == GMT_send_prebuilt_message (message, ch->t, ch, fwd,
2013 * Get the static string for identification of the channel.
2015 * @param ch Channel.
2017 * @return Static string with the channel IDs.
2020 GMCH_2s (const struct MeshChannel *ch)
2022 static char buf[64];
2025 return "(NULL Channel)";
2027 sprintf (buf, "%s:%u gid:%X (%X / %X)",
2028 GMT_2s (ch->t), ch->port, ch->gid, ch->lid_root, ch->lid_dest);