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 MeshChannelQueue *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 (reliable) messages pending ACK for this channel.
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.rel_value_us = 0;
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);
471 LOG (GNUNET_ERROR_TYPE_DEBUG, " COPYFREE RECV %p\n", copy);
476 LOG (GNUNET_ERROR_TYPE_DEBUG,
477 " reliable && don't have %u, next is %u\n",
483 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_buffered_data END\n");
488 * Allow a client to send more data.
490 * In case the client was already allowed to send data, do nothing.
493 * @param fwd Is this a FWD ACK? (FWD ACKs are sent to root)
496 send_client_ack (struct MeshChannel *ch, int fwd)
498 struct MeshChannelReliability *rel = fwd ? ch->root_rel : ch->dest_rel;
500 LOG (GNUNET_ERROR_TYPE_DEBUG,
501 " sending %s ack to client on channel %s\n",
502 GM_f2s (fwd), GMCH_2s (ch));
510 if (GNUNET_YES == rel->client_allowed)
512 LOG (GNUNET_ERROR_TYPE_DEBUG, " already allowed\n");
515 rel->client_allowed = GNUNET_YES;
517 GML_send_ack (fwd ? ch->root : ch->dest, fwd ? ch->lid_root : ch->lid_dest);
522 * Notify the root that the destination rejected the channel.
524 * @param ch Rejected channel.
527 send_client_nack (struct MeshChannel *ch)
529 if (NULL == ch->root)
534 GML_send_nack (ch->root, ch->lid_root);
539 * Notify a client that the channel is no longer valid.
541 * @param ch Channel that is destroyed.
542 * @param local_only Should we avoid sending it to other peers?
545 send_destroy (struct MeshChannel *ch, int local_only)
547 struct GNUNET_MESH_ChannelManage msg;
549 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY);
550 msg.header.size = htons (sizeof (msg));
551 msg.chid = htonl (ch->gid);
553 /* If root is not NULL, notify.
554 * If it's NULL, check lid_root. When a local destroy comes in, root
555 * is set to NULL but lid_root is left untouched. In this case, do nothing,
556 * the client is the one who reuqested the channel to be destroyed.
558 if (NULL != ch->root)
559 GML_send_channel_destroy (ch->root, ch->lid_root);
560 else if (0 == ch->lid_root && GNUNET_NO == local_only)
561 GMCH_send_prebuilt_message (&msg.header, ch, GNUNET_NO, NULL);
563 if (NULL != ch->dest)
564 GML_send_channel_destroy (ch->dest, ch->lid_dest);
565 else if (0 == ch->lid_dest && GNUNET_NO == local_only)
566 GMCH_send_prebuilt_message (&msg.header, ch, GNUNET_YES, NULL);
571 * Destroy all reliable messages queued for a channel,
572 * during a channel destruction.
573 * Frees the reliability structure itself.
575 * @param rel Reliability data for a channel.
578 channel_rel_free_all (struct MeshChannelReliability *rel)
580 struct MeshReliableMessage *copy;
581 struct MeshReliableMessage *next;
586 for (copy = rel->head_recv; NULL != copy; copy = next)
589 GNUNET_CONTAINER_DLL_remove (rel->head_recv, rel->tail_recv, copy);
590 LOG (GNUNET_ERROR_TYPE_DEBUG, " COPYFREE BATCH RECV %p\n", copy);
593 for (copy = rel->head_sent; NULL != copy; copy = next)
596 GNUNET_CONTAINER_DLL_remove (rel->head_sent, rel->tail_sent, copy);
597 LOG (GNUNET_ERROR_TYPE_DEBUG, " COPYFREE BATCH %p\n", copy);
600 if (GNUNET_SCHEDULER_NO_TASK != rel->retry_task)
602 GNUNET_SCHEDULER_cancel (rel->retry_task);
604 if (NULL != rel->ack_q)
605 GMT_cancel (rel->ack_q->q);
611 * Mark future messages as ACK'd.
613 * @param rel Reliability data.
614 * @param msg DataACK message with a bitfield of future ACK'd messages.
617 channel_rel_free_sent (struct MeshChannelReliability *rel,
618 const struct GNUNET_MESH_DataACK *msg)
620 struct MeshReliableMessage *copy;
621 struct MeshReliableMessage *next;
628 bitfield = msg->futures;
629 mid = ntohl (msg->mid);
630 LOG (GNUNET_ERROR_TYPE_DEBUG,
631 "!!! free_sent_reliable %u %llX\n",
633 LOG (GNUNET_ERROR_TYPE_DEBUG,
634 " rel %p, head %p\n",
635 rel, rel->head_sent);
636 for (i = 0, copy = rel->head_sent;
637 i < 64 && NULL != copy && 0 != bitfield;
640 LOG (GNUNET_ERROR_TYPE_DEBUG,
641 " trying bit %u (mid %u)\n",
644 if (0 == (bitfield & mask))
647 LOG (GNUNET_ERROR_TYPE_DEBUG, " set!\n");
648 /* Bit was set, clear the bit from the bitfield */
651 /* The i-th bit was set. Do we have that copy? */
652 /* Skip copies with mid < target */
653 target = mid + i + 1;
654 LOG (GNUNET_ERROR_TYPE_DEBUG, " target %u\n", target);
655 while (NULL != copy && GM_is_pid_bigger (target, copy->mid))
658 /* Did we run out of copies? (previously freed, it's ok) */
661 LOG (GNUNET_ERROR_TYPE_DEBUG, "run out of copies...\n");
665 /* Did we overshoot the target? (previously freed, it's ok) */
666 if (GM_is_pid_bigger (copy->mid, target))
668 LOG (GNUNET_ERROR_TYPE_DEBUG, " next copy %u\n", copy->mid);
672 /* Now copy->mid == target, free it */
674 rel_message_free (copy, GNUNET_YES);
677 LOG (GNUNET_ERROR_TYPE_DEBUG, "free_sent_reliable END\n");
682 * We haven't received an ACK after a certain time: restransmit the message.
684 * @param cls Closure (MeshReliableMessage with the message to restransmit)
685 * @param tc TaskContext.
688 channel_retransmit_message (void *cls,
689 const struct GNUNET_SCHEDULER_TaskContext *tc)
691 struct MeshChannelReliability *rel = cls;
692 struct MeshReliableMessage *copy;
693 struct MeshChannel *ch;
694 struct GNUNET_MESH_Data *payload;
697 rel->retry_task = GNUNET_SCHEDULER_NO_TASK;
698 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
702 copy = rel->head_sent;
709 payload = (struct GNUNET_MESH_Data *) ©[1];
710 fwd = (rel == ch->root_rel);
712 /* Message not found in the queue that we are going to use. */
713 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! RETRANSMIT %u\n", copy->mid);
715 GMCH_send_prebuilt_message (&payload->header, ch, fwd, copy);
716 GNUNET_STATISTICS_update (stats, "# data retransmitted", 1, GNUNET_NO);
721 * Destroy a reliable message after it has been acknowledged, either by
722 * direct mid ACK or bitfield. Updates the appropriate data structures and
723 * timers and frees all memory.
725 * @param copy Message that is no longer needed: remote peer got it.
726 * @param update_time Is the timing information relevant?
727 * If this message is ACK in a batch the timing information
728 * is skewed by the retransmission, count only for the
729 * retransmitted message.
732 rel_message_free (struct MeshReliableMessage *copy, int update_time)
734 struct MeshChannelReliability *rel;
735 struct GNUNET_TIME_Relative time;
738 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! Freeing %u\n", copy->mid);
741 time = GNUNET_TIME_absolute_get_duration (copy->timestamp);
742 if (0 == rel->expected_delay.rel_value_us)
743 rel->expected_delay = time;
746 rel->expected_delay.rel_value_us *= 7;
747 rel->expected_delay.rel_value_us += time.rel_value_us;
748 rel->expected_delay.rel_value_us /= 8;
750 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! took %s\n",
751 GNUNET_STRINGS_relative_time_to_string (time, GNUNET_NO));
752 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! new expected delay %s\n",
753 GNUNET_STRINGS_relative_time_to_string (rel->expected_delay,
755 rel->retry_timer = rel->expected_delay;
759 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! batch free, ignoring timing\n");
761 rel->ch->pending_messages--;
762 if (GNUNET_NO != rel->ch->destroy && 0 == rel->ch->pending_messages)
764 struct MeshTunnel3 *t = rel->ch->t;
765 GMCH_destroy (rel->ch);
766 GMT_destroy_if_empty (t);
770 GMT_cancel (copy->q->q);
772 GNUNET_CONTAINER_DLL_remove (rel->head_sent, rel->tail_sent, copy);
773 LOG (GNUNET_ERROR_TYPE_DEBUG, " COPYFREE %p\n", copy);
779 * Confirm we got a channel create.
781 * @param ch The channel to confirm.
782 * @param fwd Should we send a FWD ACK? (going dest->root)
785 channel_send_ack (struct MeshChannel *ch, int fwd)
787 struct GNUNET_MESH_ChannelManage msg;
789 msg.header.size = htons (sizeof (msg));
790 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK);
791 LOG (GNUNET_ERROR_TYPE_DEBUG,
792 " sending channel %s ack for channel %s\n",
793 GM_f2s (fwd), GMCH_2s (ch));
795 msg.chid = htonl (ch->gid);
796 GMCH_send_prebuilt_message (&msg.header, ch, !fwd, NULL);
801 * Notify that a channel create didn't succeed.
803 * @param ch The channel to reject.
806 channel_send_nack (struct MeshChannel *ch)
808 struct GNUNET_MESH_ChannelManage msg;
810 msg.header.size = htons (sizeof (msg));
811 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK);
812 LOG (GNUNET_ERROR_TYPE_DEBUG,
813 " sending channel NACK for channel %s\n",
816 msg.chid = htonl (ch->gid);
817 GMCH_send_prebuilt_message (&msg.header, ch, GNUNET_NO, NULL);
822 * Channel was ACK'd by remote peer, mark as ready and cancel retransmission.
824 * @param ch Channel to mark as ready.
825 * @param fwd Was the ACK message a FWD ACK? (dest->root, SYNACK)
828 channel_confirm (struct MeshChannel *ch, int fwd)
830 struct MeshChannelReliability *rel;
831 struct MeshReliableMessage *copy;
832 struct MeshReliableMessage *next;
834 LOG (GNUNET_ERROR_TYPE_DEBUG,
835 " channel confirm %s %s:%X\n",
836 GM_f2s (fwd), GMT_2s (ch->t), ch->gid);
837 ch->state = MESH_CHANNEL_READY;
839 rel = fwd ? ch->root_rel : ch->dest_rel;
840 rel->client_ready = GNUNET_YES;
841 for (copy = rel->head_sent; NULL != copy; copy = next)
843 struct GNUNET_MessageHeader *msg;
846 msg = (struct GNUNET_MessageHeader *) ©[1];
847 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE)
849 rel_message_free (copy, GNUNET_YES);
853 send_client_ack (ch, fwd);
855 /* In case of a FWD ACK (SYNACK) send a BCK ACK (ACK). */
857 channel_send_ack (ch, !fwd);
862 * Message has been sent: start retransmission timer.
864 * @param cls Closure (queue structure).
866 * @param q Queue handler (no longer valid).
867 * @param type Type of message.
868 * @param size Size of the message.
871 ch_message_sent (void *cls,
872 struct MeshTunnel3 *t,
873 struct MeshTunnel3Queue *q,
874 uint16_t type, size_t size)
876 struct MeshChannelQueue *ch_q = cls;
877 struct MeshReliableMessage *copy = ch_q->copy;
878 struct MeshChannelReliability *rel;
882 case GNUNET_MESSAGE_TYPE_MESH_DATA:
883 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! SENT %u %s (c: %p, q: %p)\n",
884 copy->mid, GM_m2s (type), copy, copy->q);
885 GNUNET_assert (ch_q == copy->q);
886 copy->timestamp = GNUNET_TIME_absolute_get ();
888 if (GNUNET_SCHEDULER_NO_TASK == rel->retry_task)
890 if (0 != rel->expected_delay.rel_value_us)
893 GNUNET_TIME_relative_multiply (rel->expected_delay,
894 MESH_RETRANSMIT_MARGIN);
898 rel->retry_timer = MESH_RETRANSMIT_TIME;
901 GNUNET_SCHEDULER_add_delayed (rel->retry_timer,
902 &channel_retransmit_message,
909 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
911 GNUNET_assert (rel->ack_q == ch_q);
927 * Save a copy to retransmit in case it gets lost.
929 * Initializes all needed callbacks and timers.
931 * @param ch Channel this message goes on.
932 * @param msg Message to copy.
933 * @param fwd Is this fwd traffic?
935 static struct MeshReliableMessage *
936 channel_save_copy (struct MeshChannel *ch,
937 const struct GNUNET_MessageHeader *msg,
940 struct MeshChannelReliability *rel;
941 struct MeshReliableMessage *copy;
946 rel = fwd ? ch->root_rel : ch->dest_rel;
947 mid = rel->mid_send - 1;
948 type = ntohs (msg->type);
949 size = ntohs (msg->size);
951 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! SAVE %u %s\n", mid, GM_m2s (type));
952 copy = GNUNET_malloc (sizeof (struct MeshReliableMessage) + size);
953 LOG (GNUNET_ERROR_TYPE_DEBUG, " at %p\n", copy);
957 memcpy (©[1], msg, size);
958 GNUNET_CONTAINER_DLL_insert_tail (rel->head_sent, rel->tail_sent, copy);
959 ch->pending_messages++;
966 * Create a new channel.
968 * @param t Tunnel this channel is in.
969 * @param owner Client that owns the channel, NULL for foreign channels.
970 * @param lid_root Local ID for root client.
972 * @return A new initialized channel. NULL on error.
974 static struct MeshChannel *
975 channel_new (struct MeshTunnel3 *t,
976 struct MeshClient *owner,
977 MESH_ChannelNumber lid_root)
979 struct MeshChannel *ch;
981 ch = GNUNET_new (struct MeshChannel);
983 ch->lid_root = lid_root;
986 GNUNET_STATISTICS_update (stats, "# channels", 1, GNUNET_NO);
990 ch->gid = GMT_get_next_chid (t);
991 GML_channel_add (owner, lid_root, ch);
993 GMT_add_channel (t, ch);
1000 * Set options in a channel, extracted from a bit flag field
1002 * @param ch Channel to set options to.
1003 * @param options Bit array in host byte order.
1006 channel_set_options (struct MeshChannel *ch, uint32_t options)
1008 ch->nobuffer = (options & GNUNET_MESH_OPTION_NOBUFFER) != 0 ?
1009 GNUNET_YES : GNUNET_NO;
1010 ch->reliable = (options & GNUNET_MESH_OPTION_RELIABLE) != 0 ?
1011 GNUNET_YES : GNUNET_NO;
1015 is_loopback (const struct MeshChannel *ch)
1018 return GMT_is_loopback (ch->t);
1020 return (NULL != ch->root && NULL != ch->dest);
1025 * Handle a loopback message: call the appropriate handler for the message type.
1027 * @param ch Channel this message is on.
1028 * @param msgh Message header.
1029 * @param fwd Is this FWD traffic?
1032 handle_loopback (struct MeshChannel *ch,
1033 const struct GNUNET_MessageHeader *msgh,
1038 type = ntohs (msgh->type);
1039 LOG (GNUNET_ERROR_TYPE_DEBUG,
1040 "Loopback %s %s message!\n",
1041 GM_f2s (fwd), GM_m2s (type));
1045 case GNUNET_MESSAGE_TYPE_MESH_DATA:
1046 /* Don't send hop ACK, wait for client to ACK */
1047 GMCH_handle_data (ch, (struct GNUNET_MESH_Data *) msgh, fwd);
1050 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
1051 GMCH_handle_data_ack (ch, (struct GNUNET_MESH_DataACK *) msgh, fwd);
1054 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
1055 GMCH_handle_create (ch->t,
1056 (struct GNUNET_MESH_ChannelCreate *) msgh);
1059 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
1060 GMCH_handle_ack (ch,
1061 (struct GNUNET_MESH_ChannelManage *) msgh,
1065 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_NACK:
1066 GMCH_handle_nack (ch);
1069 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
1070 GMCH_handle_destroy (ch,
1071 (struct GNUNET_MESH_ChannelManage *) msgh,
1076 GNUNET_break_op (0);
1077 LOG (GNUNET_ERROR_TYPE_DEBUG,
1078 "end-to-end message not known (%u)\n",
1079 ntohs (msgh->type));
1085 /******************************************************************************/
1086 /******************************** API ***********************************/
1087 /******************************************************************************/
1090 * Destroy a channel and free all resources.
1092 * @param ch Channel to destroy.
1095 GMCH_destroy (struct MeshChannel *ch)
1097 struct MeshClient *c;
1102 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying channel %s:%u\n",
1103 GMT_2s (ch->t), ch->gid);
1109 GML_channel_remove (c, ch->lid_root, ch);
1115 GML_channel_remove (c, ch->lid_dest, ch);
1118 channel_rel_free_all (ch->root_rel);
1119 channel_rel_free_all (ch->dest_rel);
1121 GMT_remove_channel (ch->t, ch);
1122 GNUNET_STATISTICS_update (stats, "# channels", -1, GNUNET_NO);
1131 * @param ch Channel.
1136 GMCH_get_id (const struct MeshChannel *ch)
1143 * Get the channel tunnel.
1145 * @param ch Channel to get the tunnel from.
1147 * @return tunnel of the channel.
1149 struct MeshTunnel3 *
1150 GMCH_get_tunnel (const struct MeshChannel *ch)
1157 * Get free buffer space towards the client on a specific channel.
1159 * @param ch Channel.
1160 * @param fwd Is query about FWD traffic?
1162 * @return Free buffer space [0 - 64]
1165 GMCH_get_buffer (struct MeshChannel *ch, int fwd)
1167 struct MeshChannelReliability *rel;
1169 rel = fwd ? ch->dest_rel : ch->root_rel;
1171 /* If rel is NULL it means that the end is not yet created,
1172 * most probably is a loopback channel at the point of sending
1173 * the ChannelCreate to itself.
1178 return (64 - rel->n_recv);
1183 * Get flow control status of end point: is client allow to send?
1185 * @param ch Channel.
1186 * @param fwd Is query about FWD traffic? (Request root status).
1188 * @return #GNUNET_YES if client is allowed to send us data.
1191 GMCH_get_allowed (struct MeshChannel *ch, int fwd)
1193 struct MeshChannelReliability *rel;
1195 rel = fwd ? ch->root_rel : ch->dest_rel;
1199 /* Probably shutting down: root/dest NULL'ed to mark disconnection */
1200 GNUNET_break (GNUNET_NO != ch->destroy);
1204 return rel->client_allowed;
1209 * Is the root client for this channel on this peer?
1211 * @param ch Channel.
1212 * @param fwd Is this for fwd traffic?
1214 * @return #GNUNET_YES in case it is.
1217 GMCH_is_origin (struct MeshChannel *ch, int fwd)
1219 struct MeshClient *c;
1221 c = fwd ? ch->root : ch->dest;
1227 * Is the destination client for this channel on this peer?
1229 * @param ch Channel.
1230 * @param fwd Is this for fwd traffic?
1232 * @return #GNUNET_YES in case it is.
1235 GMCH_is_terminal (struct MeshChannel *ch, int fwd)
1237 struct MeshClient *c;
1239 c = fwd ? ch->dest : ch->root;
1245 * Notify the destination client that a new incoming channel was created.
1247 * @param ch Channel that was created.
1250 GMCH_send_create (struct MeshChannel *ch)
1254 if (NULL == ch->dest)
1258 opt |= GNUNET_YES == ch->reliable ? GNUNET_MESH_OPTION_RELIABLE : 0;
1259 opt |= GNUNET_YES == ch->nobuffer ? GNUNET_MESH_OPTION_NOBUFFER : 0;
1260 GML_send_channel_create (ch->dest, ch->lid_dest, ch->port, opt,
1261 GMT_get_destination (ch->t));
1267 * Send an end-to-end ACK message for the most recent in-sequence payload.
1269 * If channel is not reliable, do nothing.
1271 * @param ch Channel this is about.
1272 * @param fwd Is for FWD traffic? (ACK dest->owner)
1275 GMCH_send_data_ack (struct MeshChannel *ch, int fwd)
1277 struct GNUNET_MESH_DataACK msg;
1278 struct MeshChannelReliability *rel;
1279 struct MeshReliableMessage *copy;
1284 if (GNUNET_NO == ch->reliable)
1288 rel = fwd ? ch->dest_rel : ch->root_rel;
1289 ack = rel->mid_recv - 1;
1290 LOG (GNUNET_ERROR_TYPE_DEBUG,
1291 " !! Send DATA_ACK for %u\n",
1294 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_DATA_ACK);
1295 msg.header.size = htons (sizeof (msg));
1296 msg.chid = htonl (ch->gid);
1298 for (copy = rel->head_recv; NULL != copy; copy = copy->next)
1300 if (copy->type != GNUNET_MESSAGE_TYPE_MESH_DATA)
1302 LOG (GNUNET_ERROR_TYPE_DEBUG,
1303 "!! Type %s, expected DATA\n",
1304 GM_m2s (copy->type));
1307 if (copy->mid == ack + 1)
1312 delta = copy->mid - (ack + 1);
1315 mask = 0x1LL << delta;
1316 msg.futures |= mask;
1317 LOG (GNUNET_ERROR_TYPE_DEBUG,
1318 " !! setting bit for %u (delta %u) (%llX) -> %llX\n",
1319 copy->mid, delta, mask, msg.futures);
1321 msg.mid = htonl (ack);
1322 LOG (GNUNET_ERROR_TYPE_DEBUG,
1323 "!!! ACK for %u, futures %llX\n",
1326 GMCH_send_prebuilt_message (&msg.header, ch, !fwd, NULL);
1327 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_data_ack END\n");
1332 * Allow a client to send us more data, in case it was choked.
1334 * @param ch Channel.
1335 * @param fwd Is this about FWD traffic? (Root client).
1338 GMCH_allow_client (struct MeshChannel *ch, int fwd)
1340 struct MeshChannelReliability *rel;
1341 unsigned int buffer;
1343 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMCH allow\n");
1345 if (MESH_CHANNEL_READY != ch->state)
1347 LOG (GNUNET_ERROR_TYPE_DEBUG, " channel not ready yet!\n");
1351 if (GNUNET_YES == ch->reliable)
1353 rel = fwd ? ch->root_rel : ch->dest_rel;
1356 GNUNET_break (GNUNET_NO != ch->destroy);
1359 if (NULL != rel->head_sent && 64 <= rel->mid_send - rel->head_sent->mid)
1361 LOG (GNUNET_ERROR_TYPE_DEBUG, " too big MID gap! Wait for ACK.\n");
1366 if (is_loopback (ch))
1367 buffer = GMCH_get_buffer (ch, fwd);
1369 buffer = GMT_get_connections_buffer (ch->t);
1373 LOG (GNUNET_ERROR_TYPE_DEBUG, " no buffer space.\n");
1377 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space %u, allowing\n", buffer);
1378 send_client_ack (ch, fwd);
1385 * @param ch Channel.
1388 GMCH_debug (struct MeshChannel *ch)
1392 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CHANNEL ***\n");
1395 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %s:%X (%p)\n",
1396 GMT_2s (ch->t), ch->gid, ch);
1397 LOG (GNUNET_ERROR_TYPE_DEBUG, " root %p/%p\n",
1398 ch->root, ch->root_rel);
1399 if (NULL != ch->root)
1401 LOG (GNUNET_ERROR_TYPE_DEBUG, " cli %s\n", GML_2s (ch->root));
1402 LOG (GNUNET_ERROR_TYPE_DEBUG, " ready %s\n",
1403 ch->root_rel->client_ready ? "YES" : "NO");
1404 LOG (GNUNET_ERROR_TYPE_DEBUG, " id %X\n", ch->lid_root);
1406 LOG (GNUNET_ERROR_TYPE_DEBUG, " dest %p/%p\n",
1407 ch->dest, ch->dest_rel);
1408 if (NULL != ch->dest)
1410 LOG (GNUNET_ERROR_TYPE_DEBUG, " cli %s\n", GML_2s (ch->dest));
1411 LOG (GNUNET_ERROR_TYPE_DEBUG, " ready %s\n",
1412 ch->dest_rel->client_ready ? "YES" : "NO");
1413 LOG (GNUNET_ERROR_TYPE_DEBUG, " id %X\n", ch->lid_dest);
1419 * Handle an ACK given by a client.
1421 * Mark client as ready and send him any buffered data we could have for him.
1423 * @param ch Channel.
1424 * @param fwd Is this a "FWD ACK"? (FWD ACKs are sent by dest and go BCK)
1427 GMCH_handle_local_ack (struct MeshChannel *ch, int fwd)
1429 struct MeshChannelReliability *rel;
1430 struct MeshClient *c;
1432 rel = fwd ? ch->dest_rel : ch->root_rel;
1433 c = fwd ? ch->dest : ch->root;
1435 rel->client_ready = GNUNET_YES;
1436 send_client_buffered_data (ch, c, fwd);
1437 if (is_loopback (ch))
1439 unsigned int buffer;
1441 buffer = GMCH_get_buffer (ch, fwd);
1443 GMCH_allow_client (ch, fwd);
1447 GMT_send_connection_acks (ch->t);
1452 * Handle data given by a client.
1454 * Check whether the client is allowed to send in this tunnel, save if channel
1455 * is reliable and send an ACK to the client if there is still buffer space
1458 * @param ch Channel.
1459 * @param c Client which sent the data.
1460 * @param message Message.
1461 * @param fwd Is this a FWD data?
1463 * @return GNUNET_OK if everything goes well, GNUNET_SYSERR in case of en error.
1466 GMCH_handle_local_data (struct MeshChannel *ch,
1467 struct MeshClient *c,
1468 struct GNUNET_MessageHeader *message,
1471 struct MeshChannelReliability *rel;
1472 struct GNUNET_MESH_Data *payload;
1473 size_t size = ntohs (message->size);
1474 uint16_t p2p_size = sizeof(struct GNUNET_MESH_Data) + size;
1475 unsigned char cbuf[p2p_size];
1477 /* Is the client in the channel? */
1484 GNUNET_break_op (0);
1485 return GNUNET_SYSERR;
1488 rel = fwd ? ch->root_rel : ch->dest_rel;
1490 if (GNUNET_NO == rel->client_allowed)
1492 GNUNET_break_op (0);
1493 return GNUNET_SYSERR;
1496 rel->client_allowed = GNUNET_NO;
1498 /* Ok, everything is correct, send the message. */
1499 payload = (struct GNUNET_MESH_Data *) cbuf;
1500 payload->mid = htonl (rel->mid_send);
1502 memcpy (&payload[1], message, size);
1503 payload->header.size = htons (p2p_size);
1504 payload->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_DATA);
1505 payload->chid = htonl (ch->gid);
1506 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channel...\n");
1507 GMCH_send_prebuilt_message (&payload->header, ch, fwd, NULL);
1509 if (is_loopback (ch))
1511 if (GMCH_get_buffer (ch, fwd) > 0)
1512 send_client_ack (ch, fwd);
1517 if (GMT_get_connections_buffer (ch->t) > 0)
1519 send_client_ack (ch, fwd);
1527 * Handle a channel destroy requested by a client.
1529 * Destroy the channel and the tunnel in case this was the last channel.
1531 * @param ch Channel.
1532 * @param c Client that requested the destruction (to avoid notifying him).
1533 * @param is_root Is the request coming from root?
1536 GMCH_handle_local_destroy (struct MeshChannel *ch,
1537 struct MeshClient *c,
1540 struct MeshTunnel3 *t;
1542 ch->destroy = GNUNET_YES;
1543 /* Cleanup after the tunnel */
1544 if (GNUNET_NO == is_root && c == ch->dest)
1546 LOG (GNUNET_ERROR_TYPE_DEBUG, " Client %s is destination.\n", GML_2s (c));
1547 GML_client_delete_channel (c, ch, ch->lid_dest);
1550 if (GNUNET_YES == is_root && c == ch->root)
1552 LOG (GNUNET_ERROR_TYPE_DEBUG, " Client %s is owner.\n", GML_2s (c));
1553 GML_client_delete_channel (c, ch, ch->lid_root);
1558 send_destroy (ch, GNUNET_NO);
1559 if (0 == ch->pending_messages)
1562 GMT_destroy_if_empty (t);
1568 * Handle a channel create requested by a client.
1570 * Create the channel and the tunnel in case this was the first0 channel.
1572 * @param c Client that requested the creation (will be the root).
1573 * @param msg Create Channel message.
1575 * @return GNUNET_OK if everything went fine, GNUNET_SYSERR otherwise.
1578 GMCH_handle_local_create (struct MeshClient *c,
1579 struct GNUNET_MESH_ChannelMessage *msg)
1581 struct MeshChannel *ch;
1582 struct MeshTunnel3 *t;
1583 struct MeshPeer *peer;
1584 MESH_ChannelNumber chid;
1586 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s:%u\n",
1587 GNUNET_i2s (&msg->peer), ntohl (msg->port));
1588 chid = ntohl (msg->channel_id);
1590 /* Sanity check for duplicate channel IDs */
1591 if (NULL != GML_channel_get (c, chid))
1594 return GNUNET_SYSERR;
1597 peer = GMP_get (&msg->peer);
1598 GMP_add_tunnel (peer);
1599 t = GMP_get_tunnel (peer);
1601 if (GMP_get_short_id (peer) == myid)
1603 GMT_change_cstate (t, MESH_TUNNEL3_READY);
1610 /* Create channel */
1611 ch = channel_new (t, c, chid);
1615 return GNUNET_SYSERR;
1617 ch->port = ntohl (msg->port);
1618 channel_set_options (ch, ntohl (msg->opt));
1620 /* In unreliable channels, we'll use the DLL to buffer BCK data */
1621 ch->root_rel = GNUNET_new (struct MeshChannelReliability);
1622 ch->root_rel->ch = ch;
1623 ch->root_rel->expected_delay.rel_value_us = 0;
1625 LOG (GNUNET_ERROR_TYPE_DEBUG, "CREATED CHANNEL %s\n", GMCH_2s (ch));
1627 /* Send create channel */
1629 struct GNUNET_MESH_ChannelCreate msgcc;
1631 msgcc.header.size = htons (sizeof (msgcc));
1632 msgcc.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE);
1633 msgcc.chid = htonl (ch->gid);
1634 msgcc.port = msg->port;
1635 msgcc.opt = msg->opt;
1637 /* FIXME retransmit if lost */
1638 GMT_send_prebuilt_message (&msgcc.header, t, ch,
1639 GNUNET_YES, GNUNET_YES, NULL, NULL);
1646 * Handler for mesh network payload traffic.
1648 * @param ch Channel for the message.
1649 * @param msg Unencryted data message.
1650 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1651 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1652 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1653 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1656 GMCH_handle_data (struct MeshChannel *ch,
1657 const struct GNUNET_MESH_Data *msg,
1660 struct MeshChannelReliability *rel;
1661 struct MeshClient *c;
1664 /* If this is a remote (non-loopback) channel, find 'fwd'. */
1665 if (GNUNET_SYSERR == fwd)
1667 if (is_loopback (ch))
1669 /* It is a loopback channel after all... */
1673 fwd = (NULL != ch->dest) ? GNUNET_YES : GNUNET_NO;
1676 /* Initialize FWD/BCK data */
1677 c = fwd ? ch->dest : ch->root;
1678 rel = fwd ? ch->dest_rel : ch->root_rel;
1686 GNUNET_STATISTICS_update (stats, "# data received", 1, GNUNET_NO);
1688 mid = ntohl (msg->mid);
1689 LOG (GNUNET_ERROR_TYPE_DEBUG, "!! got mid %u\n", mid);
1691 if (GNUNET_NO == ch->reliable ||
1692 ( !GM_is_pid_bigger (rel->mid_recv, mid) &&
1693 GM_is_pid_bigger (rel->mid_recv + 64, mid) ) )
1695 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! RECV %u\n", mid);
1696 if (GNUNET_YES == ch->reliable)
1698 /* Is this the exact next expected messasge? */
1699 if (mid == rel->mid_recv)
1701 LOG (GNUNET_ERROR_TYPE_DEBUG, "as expected\n");
1703 send_client_data (ch, msg, fwd);
1707 LOG (GNUNET_ERROR_TYPE_DEBUG, "save for later\n");
1708 add_buffered_data (msg, rel);
1713 /* Tunnel is unreliable: send to clients directly */
1714 /* FIXME: accept Out Of Order traffic */
1715 rel->mid_recv = mid + 1;
1716 send_client_data (ch, msg, fwd);
1721 GNUNET_break_op (GM_is_pid_bigger (rel->mid_recv, mid));
1722 LOG (GNUNET_ERROR_TYPE_DEBUG,
1723 " !!! MID %u not expected (%u - %u), dropping!\n",
1724 mid, rel->mid_recv, rel->mid_recv + 63);
1727 GMCH_send_data_ack (ch, fwd);
1732 * Handler for mesh network traffic end-to-end ACKs.
1734 * @param ch Channel on which we got this message.
1735 * @param msg Data message.
1736 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1737 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1738 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1739 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1742 GMCH_handle_data_ack (struct MeshChannel *ch,
1743 const struct GNUNET_MESH_DataACK *msg,
1746 struct MeshChannelReliability *rel;
1747 struct MeshReliableMessage *copy;
1748 struct MeshReliableMessage *next;
1752 /* If this is a remote (non-loopback) channel, find 'fwd'. */
1753 if (GNUNET_SYSERR == fwd)
1755 if (is_loopback (ch))
1757 /* It is a loopback channel after all... */
1761 /* Inverted: if message came 'FWD' is a 'BCK ACK'. */
1762 fwd = (NULL != ch->dest) ? GNUNET_NO : GNUNET_YES;
1765 ack = ntohl (msg->mid);
1766 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! %s ACK %u\n",
1767 (GNUNET_YES == fwd) ? "FWD" : "BCK", ack);
1769 if (GNUNET_YES == fwd)
1779 GNUNET_break_op (0);
1783 /* Free ACK'd copies: no need to retransmit those anymore */
1784 for (work = GNUNET_NO, copy = rel->head_sent; copy != NULL; copy = next)
1786 if (GM_is_pid_bigger (copy->mid, ack))
1788 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! head %u, out!\n", copy->mid);
1789 channel_rel_free_sent (rel, msg);
1793 LOG (GNUNET_ERROR_TYPE_DEBUG, " !! id %u\n", copy->mid);
1795 rel_message_free (copy, GNUNET_YES);
1798 /* ACK client if needed */
1799 GMCH_allow_client (ch, fwd);
1801 /* If some message was free'd, update the retransmission delay */
1802 if (GNUNET_YES == work)
1804 if (GNUNET_SCHEDULER_NO_TASK != rel->retry_task)
1806 GNUNET_SCHEDULER_cancel (rel->retry_task);
1807 if (NULL != rel->head_sent && NULL == rel->head_sent->q)
1809 struct GNUNET_TIME_Absolute new_target;
1810 struct GNUNET_TIME_Relative delay;
1812 delay = GNUNET_TIME_relative_multiply (rel->retry_timer,
1813 MESH_RETRANSMIT_MARGIN);
1814 new_target = GNUNET_TIME_absolute_add (rel->head_sent->timestamp,
1816 delay = GNUNET_TIME_absolute_get_remaining (new_target);
1818 GNUNET_SCHEDULER_add_delayed (delay,
1819 &channel_retransmit_message,
1822 else /* either no more traffic to ack or traffic has just been queued */
1824 rel->retry_task = GNUNET_SCHEDULER_NO_TASK;
1827 else /* work was done but no task was pending? shouldn't happen! */
1836 * Handler for channel create messages.
1838 * Does not have fwd parameter because it's always 'FWD': channel is incoming.
1840 * @param t Tunnel this channel will be in.
1841 * @param msg Channel crate message.
1843 struct MeshChannel *
1844 GMCH_handle_create (struct MeshTunnel3 *t,
1845 const struct GNUNET_MESH_ChannelCreate *msg)
1847 MESH_ChannelNumber chid;
1848 struct MeshChannel *ch;
1849 struct MeshClient *c;
1851 chid = ntohl (msg->chid);
1853 ch = GMT_get_channel (t, chid);
1856 /* Create channel */
1857 ch = channel_new (t, NULL, 0);
1860 channel_set_options (ch, ntohl (msg->opt));
1862 /* Find a destination client */
1863 ch->port = ntohl (msg->port);
1864 LOG (GNUNET_ERROR_TYPE_DEBUG, " port %u\n", ch->port);
1865 c = GML_client_get_by_port (ch->port);
1868 /* TODO send reject */
1869 LOG (GNUNET_ERROR_TYPE_DEBUG, " no client has port registered\n");
1870 if (is_loopback (ch))
1872 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback: destroy on handler\n");
1873 channel_send_nack (ch);
1877 LOG (GNUNET_ERROR_TYPE_DEBUG, " not loopback: destroy now\n");
1878 channel_send_nack (ch);
1885 LOG (GNUNET_ERROR_TYPE_DEBUG, " client %p has port registered\n", c);
1888 add_destination (ch, c);
1889 if (GNUNET_YES == ch->reliable)
1890 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! Reliable\n");
1892 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! Not Reliable\n");
1894 GMCH_send_create (ch);
1895 channel_send_ack (ch, GNUNET_YES);
1902 * Handler for channel NACK messages.
1904 * NACK messages always go dest -> root, no need for 'fwd' or 'msg' parameter.
1906 * @param ch Channel.
1909 GMCH_handle_nack (struct MeshChannel *ch)
1911 send_client_nack (ch);
1917 * Handler for channel ack messages.
1919 * @param ch Channel.
1920 * @param msg Message.
1921 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1922 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1923 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1924 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1927 GMCH_handle_ack (struct MeshChannel *ch,
1928 const struct GNUNET_MESH_ChannelManage *msg,
1931 /* If this is a remote (non-loopback) channel, find 'fwd'. */
1932 if (GNUNET_SYSERR == fwd)
1934 if (is_loopback (ch))
1936 /* It is a loopback channel after all... */
1940 fwd = (NULL != ch->dest) ? GNUNET_YES : GNUNET_NO;
1943 channel_confirm (ch, !fwd);
1948 * Handler for channel destroy messages.
1950 * @param ch Channel to be destroyed of.
1951 * @param msg Message.
1952 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1953 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1954 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1955 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1958 GMCH_handle_destroy (struct MeshChannel *ch,
1959 const struct GNUNET_MESH_ChannelManage *msg,
1962 struct MeshTunnel3 *t;
1964 /* If this is a remote (non-loopback) channel, find 'fwd'. */
1965 if (GNUNET_SYSERR == fwd)
1967 if (is_loopback (ch))
1969 /* It is a loopback channel after all... */
1973 fwd = (NULL != ch->dest) ? GNUNET_YES : GNUNET_NO;
1977 if ( (fwd && NULL == ch->dest) || (!fwd && NULL == ch->root) )
1979 /* Not for us (don't destroy twice a half-open loopback channel) */
1984 send_destroy (ch, GNUNET_YES);
1986 GMT_destroy_if_empty (t);
1991 * Sends an already built message on a channel.
1993 * If the channel is on a loopback tunnel, notifies the appropriate destination
1996 * On a normal channel passes the message to the tunnel for encryption and
1997 * sending on a connection.
1999 * This function DOES NOT save the message for retransmission.
2001 * @param message Message to send. Function makes a copy of it.
2002 * @param ch Channel on which this message is transmitted.
2003 * @param fwd Is this a fwd message?
2004 * @param existing_copy This is a retransmission, don't save a copy.
2007 GMCH_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2008 struct MeshChannel *ch, int fwd,
2009 void *existing_copy)
2013 type = ntohs (message->type);
2014 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMCH Send %s %s on channel %s\n",
2015 GM_f2s (fwd), GM_m2s (type),
2018 if (GMT_is_loopback (ch->t))
2020 handle_loopback (ch, message, fwd);
2026 case GNUNET_MESSAGE_TYPE_MESH_DATA:
2028 if (GNUNET_YES == ch->reliable)
2030 struct MeshChannelQueue *q;
2032 q = GNUNET_new (struct MeshChannelQueue);
2034 if (NULL == existing_copy)
2035 q->copy = channel_save_copy (ch, message, fwd);
2038 q->copy = (struct MeshReliableMessage *) existing_copy;
2039 if (NULL != q->copy->q)
2041 /* Last retransmission was queued but not yet sent!
2042 * This retransmission was scheduled by a ch_message_sent which
2043 * followed a very fast RTT, so the tiny delay made the
2044 * retransmission function to execute before the previous
2045 * retransmitted message even had a chance to leave the peer.
2046 * Cancel this message and wait until the pending
2047 * retransmission leaves the peer and ch_message_sent starts
2048 * the timer for the next one.
2053 LOG (GNUNET_ERROR_TYPE_DEBUG,
2054 " using existing copy: %p {r:%p q:%p t:%u}\n",
2056 q->copy->rel, q->copy->q, q->copy->type);
2058 LOG (GNUNET_ERROR_TYPE_DEBUG, " new q: %p\n", q);
2060 q->q = GMT_send_prebuilt_message (message, ch->t, ch,
2061 fwd, NULL != existing_copy,
2062 &ch_message_sent, q);
2063 /* q itself is stored in copy */
2067 GNUNET_break (NULL == GMT_send_prebuilt_message (message, ch->t, ch,
2073 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
2075 struct MeshChannelReliability *rel;
2077 rel = fwd ? ch->root_rel : ch->dest_rel;
2078 if (NULL != rel->ack_q)
2080 GMT_cancel (rel->ack_q->q);
2081 /* ch_message_sent is called, freeing ack_q */
2083 rel->ack_q = GNUNET_new (struct MeshChannelQueue);
2084 rel->ack_q->type = type;
2085 rel->ack_q->rel = rel;
2086 rel->ack_q->q = GMT_send_prebuilt_message (message, ch->t, ch,
2093 GNUNET_break (NULL == GMT_send_prebuilt_message (message, ch->t, ch,
2101 * Get the static string for identification of the channel.
2103 * @param ch Channel.
2105 * @return Static string with the channel IDs.
2108 GMCH_2s (const struct MeshChannel *ch)
2110 static char buf[64];
2113 return "(NULL Channel)";
2115 sprintf (buf, "%s:%u gid:%X (%X / %X)",
2116 GMT_2s (ch->t), ch->port, ch->gid, ch->lid_root, ch->lid_dest);