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_enc.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..
65 * Info needed to retry a message in case it gets lost.
67 struct MeshReliableMessage
70 * Double linked list, FIFO style
72 struct MeshReliableMessage *next;
73 struct MeshReliableMessage *prev;
76 * Type of message (payload, channel management).
81 * Tunnel Reliability queue this message is in.
83 struct MeshChannelReliability *rel;
86 * ID of the message (ACK needed to free)
91 * When was this message issued (to calculate ACK delay)
93 struct GNUNET_TIME_Absolute timestamp;
95 /* struct GNUNET_MESH_Data with payload */
100 * Info about the traffic state for a client in a channel.
102 struct MeshChannelReliability
105 * Channel this is about.
107 struct MeshChannel *ch;
110 * DLL of messages sent and not yet ACK'd.
112 struct MeshReliableMessage *head_sent;
113 struct MeshReliableMessage *tail_sent;
116 * Messages pending to send.
121 * DLL of messages received out of order.
123 struct MeshReliableMessage *head_recv;
124 struct MeshReliableMessage *tail_recv;
132 * Next MID to use for outgoing traffic.
137 * Next MID expected for incoming traffic.
142 * Can we send data to the client?
147 * Task to resend/poll in case no ACK is received.
149 GNUNET_SCHEDULER_TaskIdentifier retry_task;
152 * Counter for exponential backoff.
154 struct GNUNET_TIME_Relative retry_timer;
157 * How long does it usually take to get an ACK.
159 struct GNUNET_TIME_Relative expected_delay;
164 * Struct containing all information regarding a channel to a remote client.
169 * Tunnel this channel is in.
171 struct MeshTunnel3 *t;
174 * Destination port of the channel.
179 * Global channel number ( < GNUNET_MESH_LOCAL_CHANNEL_ID_CLI)
181 MESH_ChannelNumber gid;
184 * Local tunnel number for root (owner) client.
185 * ( >= GNUNET_MESH_LOCAL_CHANNEL_ID_CLI or 0 )
187 MESH_ChannelNumber lid_root;
190 * Local tunnel number for local destination clients (incoming number)
191 * ( >= GNUNET_MESH_LOCAL_CHANNEL_ID_SERV or 0).
193 MESH_ChannelNumber lid_dest;
198 enum MeshChannelState state;
201 * Is the tunnel bufferless (minimum latency)?
206 * Is the tunnel reliable?
211 * Last time the channel was used
213 struct GNUNET_TIME_Absolute timestamp;
216 * Client owner of the tunnel, if any
218 struct MeshClient *root;
221 * Client destination of the tunnel, if any.
223 struct MeshClient *dest;
226 * Flag to signal the destruction of the channel.
227 * If this is set GNUNET_YES the channel will be destroyed
228 * when the queue is empty.
233 * Total messages pending for this channel, payload or not.
235 unsigned int pending_messages;
239 * Only present (non-NULL) at the owner of a tunnel.
241 struct MeshChannelReliability *root_rel;
245 * Only present (non-NULL) at the destination of a tunnel.
247 struct MeshChannelReliability *dest_rel;
252 /******************************************************************************/
253 /******************************* GLOBALS ***********************************/
254 /******************************************************************************/
257 * Global handle to the statistics service.
259 extern struct GNUNET_STATISTICS_Handle *stats;
262 * Local peer own ID (memory efficient handle).
264 extern GNUNET_PEER_Id myid;
267 /******************************************************************************/
268 /******************************** STATIC ***********************************/
269 /******************************************************************************/
272 * Destroy a reliable message after it has been acknowledged, either by
273 * direct mid ACK or bitfield. Updates the appropriate data structures and
274 * timers and frees all memory.
276 * @param copy Message that is no longer needed: remote peer got it.
279 rel_message_free (struct MeshReliableMessage *copy);
282 * We have received a message out of order, or the client is not ready.
283 * Buffer it until we receive an ACK from the client or the missing
284 * message from the channel.
286 * @param msg Message to buffer (MUST be of type MESH_DATA).
287 * @param rel Reliability data to the corresponding direction.
290 add_buffered_data (const struct GNUNET_MESH_Data *msg,
291 struct MeshChannelReliability *rel)
293 struct MeshReliableMessage *copy;
294 struct MeshReliableMessage *prev;
298 size = ntohs (msg->header.size);
299 mid = ntohl (msg->mid);
301 LOG (GNUNET_ERROR_TYPE_DEBUG, "add_buffered_data %u\n", mid);
303 copy = GNUNET_malloc (sizeof (*copy) + size);
306 memcpy (©[1], msg, size);
310 // FIXME do something better than O(n), although n < 64...
311 // FIXME start from the end (most messages are the latest ones)
312 for (prev = rel->head_recv; NULL != prev; prev = prev->next)
314 LOG (GNUNET_ERROR_TYPE_DEBUG, " prev %u\n", prev->mid);
315 if (GMC_is_pid_bigger (prev->mid, mid))
317 LOG (GNUNET_ERROR_TYPE_DEBUG, " bingo!\n");
318 GNUNET_CONTAINER_DLL_insert_before (rel->head_recv, rel->tail_recv,
323 LOG (GNUNET_ERROR_TYPE_DEBUG, " insert at tail!\n");
324 GNUNET_CONTAINER_DLL_insert_tail (rel->head_recv, rel->tail_recv, copy);
325 LOG (GNUNET_ERROR_TYPE_DEBUG, "add_buffered_data END\n");
329 * Add a destination client to a channel, initializing all data structures
330 * in the channel and the client.
332 * @param ch Channel to which add the destination.
333 * @param c Client which to add to the channel.
336 add_destination (struct MeshChannel *ch, struct MeshClient *c)
338 if (NULL != ch->dest)
344 /* Assign local id as destination */
345 ch->lid_dest = GML_get_next_chid (c);
347 /* Store in client's hashmap */
348 GML_channel_add (c, ch->lid_dest, ch);
350 GNUNET_break (NULL == ch->dest_rel);
351 ch->dest_rel = GNUNET_new (struct MeshChannelReliability);
352 ch->dest_rel->ch = ch;
353 ch->dest_rel->expected_delay = MESH_RETRANSMIT_TIME;
360 * Send data to a client.
362 * If the client is ready, send directly, otherwise buffer while listening
366 * @param msg Message.
367 * @param fwd Is this a fwd (root->dest) message?
370 send_client_data (struct MeshChannel *ch,
371 const struct GNUNET_MESH_Data *msg,
376 if (ch->dest_rel->client_ready)
377 GML_send_data (ch->dest, msg, ch->lid_dest);
379 add_buffered_data (msg, ch->dest_rel);
383 if (ch->root_rel->client_ready)
384 GML_send_data (ch->root, msg, ch->lid_root);
386 add_buffered_data (msg, ch->root_rel);
392 * Destroy all reliable messages queued for a channel,
393 * during a channel destruction.
394 * Frees the reliability structure itself.
396 * @param rel Reliability data for a channel.
399 channel_rel_free_all (struct MeshChannelReliability *rel)
401 struct MeshReliableMessage *copy;
402 struct MeshReliableMessage *next;
407 for (copy = rel->head_recv; NULL != copy; copy = next)
410 GNUNET_CONTAINER_DLL_remove (rel->head_recv, rel->tail_recv, copy);
413 for (copy = rel->head_sent; NULL != copy; copy = next)
416 GNUNET_CONTAINER_DLL_remove (rel->head_sent, rel->tail_sent, copy);
419 if (GNUNET_SCHEDULER_NO_TASK != rel->retry_task)
420 GNUNET_SCHEDULER_cancel (rel->retry_task);
426 * Mark future messages as ACK'd.
428 * @param rel Reliability data.
429 * @param msg DataACK message with a bitfield of future ACK'd messages.
432 channel_rel_free_sent (struct MeshChannelReliability *rel,
433 const struct GNUNET_MESH_DataACK *msg)
435 struct MeshReliableMessage *copy;
436 struct MeshReliableMessage *next;
443 bitfield = msg->futures;
444 mid = ntohl (msg->mid);
445 LOG (GNUNET_ERROR_TYPE_DEBUG,
446 "free_sent_reliable %u %llX\n",
448 LOG (GNUNET_ERROR_TYPE_DEBUG,
449 " rel %p, head %p\n",
450 rel, rel->head_sent);
451 for (i = 0, copy = rel->head_sent;
452 i < 64 && NULL != copy && 0 != bitfield;
455 LOG (GNUNET_ERROR_TYPE_DEBUG,
456 " trying bit %u (mid %u)\n",
459 if (0 == (bitfield & mask))
462 LOG (GNUNET_ERROR_TYPE_DEBUG, " set!\n");
463 /* Bit was set, clear the bit from the bitfield */
466 /* The i-th bit was set. Do we have that copy? */
467 /* Skip copies with mid < target */
468 target = mid + i + 1;
469 LOG (GNUNET_ERROR_TYPE_DEBUG, " target %u\n", target);
470 while (NULL != copy && GMC_is_pid_bigger (target, copy->mid))
473 /* Did we run out of copies? (previously freed, it's ok) */
476 LOG (GNUNET_ERROR_TYPE_DEBUG, "run out of copies...\n");
480 /* Did we overshoot the target? (previously freed, it's ok) */
481 if (GMC_is_pid_bigger (copy->mid, target))
483 LOG (GNUNET_ERROR_TYPE_DEBUG, " next copy %u\n", copy->mid);
487 /* Now copy->mid == target, free it */
489 rel_message_free (copy);
492 LOG (GNUNET_ERROR_TYPE_DEBUG, "free_sent_reliable END\n");
497 * We haven't received an ACK after a certain time: restransmit the message.
499 * @param cls Closure (MeshReliableMessage with the message to restransmit)
500 * @param tc TaskContext.
503 channel_retransmit_message (void *cls,
504 const struct GNUNET_SCHEDULER_TaskContext *tc)
506 struct MeshChannelReliability *rel = cls;
507 struct MeshReliableMessage *copy;
508 struct MeshChannel *ch;
509 struct GNUNET_MESH_Data *payload;
512 rel->retry_task = GNUNET_SCHEDULER_NO_TASK;
513 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
517 copy = rel->head_sent;
524 /* Search the message to be retransmitted in the outgoing queue.
525 * Check only the queue for the connection that is going to be used,
526 * if the message is stuck in some other connection's queue we shouldn't
528 * - cancelling it and sending the new one doesn't guarantee it's delivery,
529 * the old connection could be temporary stalled or the queue happened to
530 * be long at time of insertion.
531 * - not sending the new one could cause terrible delays the old connection
534 // FIXME access to queue elements is limited
535 payload = (struct GNUNET_MESH_Data *) ©[1];
536 fwd = (rel == ch->root_rel);
537 // c = GMT_get_connection (ch->t, fwd);
538 // hop = connection_get_hop (c, fwd);
539 // for (q = hop->queue_head; NULL != q; q = q->next)
541 // if (ntohs (payload->header.type) == q->type && ch == q->ch)
543 // struct GNUNET_MESH_Data *queued_data = q->cls;
545 // if (queued_data->mid == payload->mid)
550 /* Message not found in the queue that we are going to use. */
553 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! RETRANSMIT %u\n", copy->mid);
555 GMCH_send_prebuilt_message (&payload->header, ch, fwd);
556 GNUNET_STATISTICS_update (stats, "# data retransmitted", 1, GNUNET_NO);
560 // LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! ALREADY IN QUEUE %u\n", copy->mid);
563 rel->retry_timer = GNUNET_TIME_STD_BACKOFF (rel->retry_timer);
564 rel->retry_task = GNUNET_SCHEDULER_add_delayed (rel->retry_timer,
565 &channel_retransmit_message,
571 * Destroy a reliable message after it has been acknowledged, either by
572 * direct mid ACK or bitfield. Updates the appropriate data structures and
573 * timers and frees all memory.
575 * @param copy Message that is no longer needed: remote peer got it.
578 rel_message_free (struct MeshReliableMessage *copy)
580 struct MeshChannelReliability *rel;
581 struct GNUNET_TIME_Relative time;
584 time = GNUNET_TIME_absolute_get_duration (copy->timestamp);
585 rel->expected_delay.rel_value_us *= 7;
586 rel->expected_delay.rel_value_us += time.rel_value_us;
587 rel->expected_delay.rel_value_us /= 8;
589 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! Freeing %u\n", copy->mid);
590 LOG (GNUNET_ERROR_TYPE_DEBUG, " n_sent %u\n", rel->n_sent);
591 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! took %s\n",
592 GNUNET_STRINGS_relative_time_to_string (time, GNUNET_NO));
593 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! new expected delay %s\n",
594 GNUNET_STRINGS_relative_time_to_string (rel->expected_delay,
596 rel->retry_timer = rel->expected_delay;
597 GNUNET_CONTAINER_DLL_remove (rel->head_sent, rel->tail_sent, copy);
603 * Confirm we got a channel create.
605 * @param ch The channel to confirm.
606 * @param fwd Should we send a FWD ACK? (going dest->root)
609 channel_send_ack (struct MeshChannel *ch, int fwd)
611 struct GNUNET_MESH_ChannelManage msg;
613 msg.header.size = htons (sizeof (msg));
614 msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK);
615 LOG (GNUNET_ERROR_TYPE_DEBUG,
616 " sending channel %s ack for channel %s\n",
617 fwd ? "FWD" : "BCK", GMCH_2s (ch));
619 msg.chid = htonl (ch->gid);
620 GMCH_send_prebuilt_message (&msg.header, ch, !fwd);
625 * Channel was ACK'd by remote peer, mark as ready and cancel retransmission.
627 * @param ch Channel to mark as ready.
628 * @param fwd Was the ACK message sent fwd? (dest->root, SYNACK)
631 channel_confirm (struct MeshChannel *ch, int fwd)
633 struct MeshChannelReliability *rel;
634 struct MeshReliableMessage *copy;
635 struct MeshReliableMessage *next;
637 LOG (GNUNET_ERROR_TYPE_DEBUG,
638 " channel confirm %s %s:%X\n",
639 fwd ? "FWD" : "BCK", GMT_2s (ch->t), ch->gid);
640 ch->state = MESH_CHANNEL_READY;
642 rel = fwd ? ch->root_rel : ch->dest_rel;
643 for (copy = rel->head_sent; NULL != copy; copy = next)
645 struct GNUNET_MessageHeader *msg;
648 msg = (struct GNUNET_MessageHeader *) ©[1];
649 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE)
651 rel_message_free (copy);
655 GML_send_ack (fwd ? ch->root : ch->dest, fwd ? ch->lid_root : ch->lid_dest);
657 /* In case of a FWD ACk (SYNACK) send a BCK ACK (ACK). */
659 channel_send_ack (ch, !fwd);
664 * Save a copy to retransmit in case it gets lost.
666 * Initializes all needed callbacks and timers.
668 * @param ch Channel this message goes on.
669 * @param msg Message to copy.
670 * @param fwd Is this fwd traffic?
673 channel_save_copy (struct MeshChannel *ch,
674 const struct GNUNET_MessageHeader *msg,
677 struct MeshChannelReliability *rel;
678 struct MeshReliableMessage *copy;
683 rel = fwd ? ch->root_rel : ch->dest_rel;
685 type = ntohs (msg->type);
686 size = ntohs (msg->size);
688 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! SAVE %u\n", mid);
689 copy = GNUNET_malloc (sizeof (struct MeshReliableMessage) + size);
691 copy->timestamp = GNUNET_TIME_absolute_get ();
694 memcpy (©[1], msg, size);
696 LOG (GNUNET_ERROR_TYPE_DEBUG, " n_sent %u\n", rel->n_sent);
697 GNUNET_CONTAINER_DLL_insert_tail (rel->head_sent, rel->tail_sent, copy);
698 if (GNUNET_SCHEDULER_NO_TASK == rel->retry_task)
701 GNUNET_TIME_relative_multiply (rel->expected_delay,
702 MESH_RETRANSMIT_MARGIN);
704 GNUNET_SCHEDULER_add_delayed (rel->retry_timer,
705 &channel_retransmit_message,
713 * Send a buffered message to the client, for in order delivery or
714 * as result of client ACK.
716 * @param ch Channel on which to empty the message buffer.
717 * @param c Client to send to.
718 * @param fwd Is this to send FWD data?.
721 send_client_buffered_data (struct MeshChannel *ch,
722 struct MeshClient *c,
725 struct MeshReliableMessage *copy;
726 struct MeshChannelReliability *rel;
728 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_buffered_data\n");
729 rel = fwd ? ch->dest_rel : ch->root_rel;
730 if (GNUNET_NO == rel->client_ready)
732 LOG (GNUNET_ERROR_TYPE_DEBUG, "client not ready\n");
736 copy = rel->head_recv;
737 /* We never buffer channel management messages */
740 if (copy->mid == rel->mid_recv || GNUNET_NO == ch->reliable)
742 struct GNUNET_MESH_Data *msg = (struct GNUNET_MESH_Data *) ©[1];
744 LOG (GNUNET_ERROR_TYPE_DEBUG,
745 " have %u! now expecting %u\n",
746 copy->mid, rel->mid_recv + 1);
747 send_client_data (ch, msg, fwd);
750 GNUNET_CONTAINER_DLL_remove (rel->head_recv, rel->tail_recv, copy);
755 LOG (GNUNET_ERROR_TYPE_DEBUG,
756 " reliable && don't have %u, next is %u\n",
762 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_buffered_data END\n");
769 * Destroy a channel and free all resources.
771 * @param ch Channel to destroy.
774 channel_destroy (struct MeshChannel *ch)
776 struct MeshClient *c;
781 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying channel %s:%u\n",
782 GMT_2s (ch->t), ch->gid);
788 GML_channel_remove (c, ch->lid_root, ch);
794 GML_channel_remove (c, ch->lid_dest, ch);
797 channel_rel_free_all (ch->root_rel);
798 channel_rel_free_all (ch->dest_rel);
800 GMT_remove_channel (ch->t, ch);
801 GNUNET_STATISTICS_update (stats, "# channels", -1, GNUNET_NO);
808 * Create a new channel.
810 * @param t Tunnel this channel is in.
811 * @param owner Client that owns the channel, NULL for foreign channels.
812 * @param lid_root Local ID for root client.
814 * @return A new initialized channel. NULL on error.
816 static struct MeshChannel *
817 channel_new (struct MeshTunnel3 *t,
818 struct MeshClient *owner,
819 MESH_ChannelNumber lid_root)
821 struct MeshChannel *ch;
823 ch = GNUNET_new (struct MeshChannel);
825 ch->lid_root = lid_root;
828 GNUNET_STATISTICS_update (stats, "# channels", 1, GNUNET_NO);
832 ch->gid = GMT_get_next_chid (t);
833 GML_channel_add (owner, lid_root, ch);
835 GMT_add_channel (t, ch);
842 * Set options in a channel, extracted from a bit flag field
844 * @param ch Channel to set options to.
845 * @param options Bit array in host byte order.
848 channel_set_options (struct MeshChannel *ch, uint32_t options)
850 ch->nobuffer = (options & GNUNET_MESH_OPTION_NOBUFFER) != 0 ?
851 GNUNET_YES : GNUNET_NO;
852 ch->reliable = (options & GNUNET_MESH_OPTION_RELIABLE) != 0 ?
853 GNUNET_YES : GNUNET_NO;
858 * Handle a loopback message: call the appropriate handler for the message type.
860 * @param ch Channel this message is on.
861 * @param msgh Message header.
862 * @param fwd Is this FWD traffic?
865 handle_loopback (struct MeshChannel *ch,
866 const struct GNUNET_MessageHeader *msgh,
871 type = ntohs (msgh->type);
872 LOG (GNUNET_ERROR_TYPE_DEBUG,
873 "Loopback %s %s message!\n",
874 fwd ? "FWD" : "BCK", GNUNET_MESH_DEBUG_M2S (type));
878 case GNUNET_MESSAGE_TYPE_MESH_DATA:
879 /* Don't send hop ACK, wait for client to ACK */
880 GMCH_handle_data (ch, (struct GNUNET_MESH_Data *) msgh, fwd);
883 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
884 GMCH_handle_data_ack (ch, (struct GNUNET_MESH_DataACK *) msgh, fwd);
887 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
888 GMCH_handle_create (ch->t,
889 (struct GNUNET_MESH_ChannelCreate *) msgh,
893 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
895 (struct GNUNET_MESH_ChannelManage *) msgh,
899 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
900 GMCH_handle_destroy (ch,
901 (struct GNUNET_MESH_ChannelManage *) msgh,
907 LOG (GNUNET_ERROR_TYPE_DEBUG,
908 "end-to-end message not known (%u)\n",
915 /******************************************************************************/
916 /******************************** API ***********************************/
917 /******************************************************************************/
928 GMCH_get_id (const struct MeshChannel *ch)
935 * Get the channel tunnel.
937 * @param ch Channel to get the tunnel from.
939 * @return tunnel of the channel.
942 GMCH_get_tunnel (const struct MeshChannel *ch)
949 * Get free buffer space towards the client on a specific channel.
952 * @param fwd Is query about FWD traffic?
954 * @return Free buffer space [0 - 64]
957 GMCH_get_buffer (struct MeshChannel *ch, int fwd)
959 struct MeshChannelReliability *rel;
961 rel = fwd ? ch->dest_rel : ch->root_rel;
963 /* If rel is NULL it means that the end is not yet created,
964 * most probably is a loopback channel at the point of sending
965 * the ChannelCreate to itself.
970 return (64 - rel->n_recv);
975 * Is the root client for this channel on this peer?
978 * @param fwd Is this for fwd traffic?
980 * @return GNUNET_YES in case it is.
983 GMCH_is_origin (struct MeshChannel *ch, int fwd)
985 struct MeshClient *c;
987 c = fwd ? ch->root : ch->dest;
993 * Is the destination client for this channel on this peer?
996 * @param fwd Is this for fwd traffic?
998 * @return GNUNET_YES in case it is.
1001 GMCH_is_terminal (struct MeshChannel *ch, int fwd)
1003 struct MeshClient *c;
1005 c = fwd ? ch->dest : ch->root;
1011 * Notify the destination client that a new incoming channel was created.
1013 * @param ch Channel that was created.
1016 GMCH_send_create (struct MeshChannel *ch)
1020 if (NULL == ch->dest)
1024 opt |= GNUNET_YES == ch->reliable ? GNUNET_MESH_OPTION_RELIABLE : 0;
1025 opt |= GNUNET_YES == ch->nobuffer ? GNUNET_MESH_OPTION_NOBUFFER : 0;
1026 GML_send_channel_create (ch->dest, ch->lid_dest, ch->port, opt,
1027 GMT_get_destination (ch->t));
1032 * Notify a client that the channel is no longer valid.
1033 * FIXME send on tunnel if some client == NULL?
1035 * @param ch Channel that is destroyed.
1038 GMCH_send_destroy (struct MeshChannel *ch)
1040 if (NULL != ch->root)
1041 GML_send_channel_destroy (ch->root, ch->lid_root);
1043 if (NULL != ch->dest)
1044 GML_send_channel_destroy (ch->dest, ch->lid_dest);
1049 * Send data on a channel.
1051 * If the destination is local, send it to client, otherwise encrypt and
1055 * @param msg Message.
1056 * @param fwd Is this a fwd (root->dest) message?
1059 GMCH_send_data (struct MeshChannel *ch,
1060 const struct GNUNET_MESH_Data *msg,
1063 if (GMCH_is_terminal (ch, fwd))
1065 GML_send_data (fwd ? ch->dest : ch->root,
1067 fwd ? ch->lid_dest : ch->lid_root);
1071 GMT_send_prebuilt_message (&msg->header, ch->t, ch, fwd);
1077 * Send an end-to-end ACK message for the most recent in-sequence payload.
1079 * If channel is not reliable, do nothing.
1081 * @param ch Channel this is about.
1082 * @param fwd Is for FWD traffic? (ACK dest->owner)
1085 GMCH_send_data_ack (struct MeshChannel *ch, int fwd)
1087 struct GNUNET_MESH_DataACK msg;
1088 struct MeshChannelReliability *rel;
1089 struct MeshReliableMessage *copy;
1094 if (GNUNET_NO == ch->reliable)
1098 rel = fwd ? ch->dest_rel : ch->root_rel;
1099 LOG (GNUNET_ERROR_TYPE_DEBUG,
1100 "send_data_ack for %u\n",
1103 type = GNUNET_MESSAGE_TYPE_MESH_DATA_ACK;
1104 msg.header.type = htons (type);
1105 msg.header.size = htons (sizeof (msg));
1106 msg.chid = htonl (ch->gid);
1107 msg.mid = htonl (rel->mid_recv - 1);
1109 for (copy = rel->head_recv; NULL != copy; copy = copy->next)
1111 if (copy->type != type)
1113 delta = copy->mid - rel->mid_recv;
1116 mask = 0x1LL << delta;
1117 msg.futures |= mask;
1118 LOG (GNUNET_ERROR_TYPE_DEBUG,
1119 " setting bit for %u (delta %u) (%llX) -> %llX\n",
1120 copy->mid, delta, mask, msg.futures);
1122 LOG (GNUNET_ERROR_TYPE_DEBUG, " final futures %llX\n", msg.futures);
1124 GMCH_send_prebuilt_message (&msg.header, ch, fwd);
1125 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_data_ack END\n");
1132 * @param ch Channel.
1135 GMCH_debug (struct MeshChannel *ch)
1139 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CHANNEL ***\n");
1142 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %s:%X (%p)\n",
1143 GMT_2s (ch->t), ch->gid, ch);
1144 LOG (GNUNET_ERROR_TYPE_DEBUG, " root %p/%p\n",
1145 ch->root, ch->root_rel);
1146 if (NULL != ch->root)
1148 LOG (GNUNET_ERROR_TYPE_DEBUG, " cli %s\n", GML_2s (ch->root));
1149 LOG (GNUNET_ERROR_TYPE_DEBUG, " ready %s\n",
1150 ch->root_rel->client_ready ? "YES" : "NO");
1151 LOG (GNUNET_ERROR_TYPE_DEBUG, " id %X\n", ch->lid_root);
1153 LOG (GNUNET_ERROR_TYPE_DEBUG, " dest %p/%p\n",
1154 ch->dest, ch->dest_rel);
1155 if (NULL != ch->dest)
1157 LOG (GNUNET_ERROR_TYPE_DEBUG, " cli %s\n", GML_2s (ch->dest));
1158 LOG (GNUNET_ERROR_TYPE_DEBUG, " ready %s\n",
1159 ch->dest_rel->client_ready ? "YES" : "NO");
1160 LOG (GNUNET_ERROR_TYPE_DEBUG, " id %X\n", ch->lid_dest);
1166 * Handle an ACK given by a client.
1168 * Mark client as ready and send him any buffered data we could have for him.
1170 * @param ch Channel.
1171 * @param fwd Is this a "FWD ACK"? (FWD ACKs are sent by root and go BCK)
1174 GMCH_handle_local_ack (struct MeshChannel *ch, int fwd)
1176 struct MeshChannelReliability *rel;
1177 struct MeshClient *c;
1179 rel = fwd ? ch->dest_rel : ch->root_rel;
1180 c = fwd ? ch->dest : ch->root;
1182 rel->client_ready = GNUNET_YES;
1183 send_client_buffered_data (ch, c, fwd);
1184 GMC_send_ack (NULL, ch, fwd);
1189 * Handle data given by a client.
1191 * Check whether the client is allowed to send in this tunnel, save if channel
1192 * is reliable and send an ACK to the client if there is still buffer space
1195 * @param ch Channel.
1196 * @param fwd Is this a FWD data?
1198 * @return GNUNET_OK if everything goes well, GNUNET_SYSERR in case of en error.
1201 GMCH_handle_local_data (struct MeshChannel *ch,
1202 struct MeshClient *c,
1203 struct GNUNET_MessageHeader *message,
1206 struct MeshChannelReliability *rel;
1207 struct GNUNET_MESH_Data *payload;
1208 size_t size = ntohs (message->size);
1209 uint16_t p2p_size = sizeof(struct GNUNET_MESH_Data) + size;
1210 unsigned char cbuf[p2p_size];
1212 /* Is the client in the channel? */
1220 return GNUNET_SYSERR;
1223 rel = fwd ? ch->root_rel : ch->dest_rel;
1225 /* Ok, everything is correct, send the message. */
1226 payload = (struct GNUNET_MESH_Data *) cbuf;
1227 payload->mid = htonl (rel->mid_send);
1229 memcpy (&payload[1], message, size);
1230 payload->header.size = htons (p2p_size);
1231 payload->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_DATA);
1232 payload->chid = htonl (ch->gid);
1233 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channel...\n");
1234 GMCH_send_prebuilt_message (&payload->header, ch, fwd);
1236 if (GNUNET_YES == ch->reliable)
1237 channel_save_copy (ch, &payload->header, fwd);
1238 if (GMT_get_buffer (ch->t, fwd) > 0)
1240 MESH_ChannelNumber ackid;
1241 ackid = fwd ? ch->lid_root : ch->lid_dest;
1242 LOG (GNUNET_ERROR_TYPE_DEBUG,
1243 " sending ack to client (%X)\n", ackid);
1244 GML_send_ack (c, ackid);
1252 * Handle a channel destroy requested by a client.
1254 * Destroy the channel and the tunnel in case this was the last channel.
1256 * @param ch Channel.
1257 * @param c Client that requested the destruction (to avoid notifying him).
1260 GMCH_handle_local_destroy (struct MeshChannel *ch,
1261 struct MeshClient *c)
1263 struct MeshTunnel3 *t;
1265 /* Cleanup after the tunnel */
1268 LOG (GNUNET_ERROR_TYPE_DEBUG, " Client %s is destination.\n", GML_2s (c));
1269 GML_client_delete_channel (c, ch, ch->lid_dest);
1274 LOG (GNUNET_ERROR_TYPE_DEBUG, " Client %s is owner.\n", GML_2s (c));
1275 GML_client_delete_channel (c, ch, ch->lid_root);
1280 GMCH_send_destroy (ch);
1281 channel_destroy (ch);
1282 GMT_destroy_if_empty (t);
1287 * Handle a channel create requested by a client.
1289 * Create the channel and the tunnel in case this was the first0 channel.
1291 * @param c Client that requested the creation (will be the root).
1292 * @param msg Create Channel message.
1294 * @return GNUNET_OK if everything went fine, GNUNET_SYSERR otherwise.
1297 GMCH_handle_local_create (struct MeshClient *c,
1298 struct GNUNET_MESH_ChannelMessage *msg)
1300 struct MeshChannel *ch;
1301 struct MeshTunnel3 *t;
1302 struct MeshPeer *peer;
1303 MESH_ChannelNumber chid;
1305 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s:%u\n",
1306 GNUNET_i2s (&msg->peer), ntohl (msg->port));
1307 chid = ntohl (msg->channel_id);
1309 /* Sanity check for duplicate channel IDs */
1310 if (NULL != GML_channel_get (c, chid))
1313 return GNUNET_SYSERR;
1316 peer = GMP_get (&msg->peer);
1317 GMP_add_tunnel (peer);
1318 t = GMP_get_tunnel (peer);
1320 if (GMP_get_short_id (peer) == myid)
1322 GMT_change_state (t, MESH_TUNNEL3_READY);
1329 /* Create channel */
1330 ch = channel_new (t, c, chid);
1334 return GNUNET_SYSERR;
1336 ch->port = ntohl (msg->port);
1337 channel_set_options (ch, ntohl (msg->opt));
1339 /* In unreliable channels, we'll use the DLL to buffer BCK data */
1340 ch->root_rel = GNUNET_new (struct MeshChannelReliability);
1341 ch->root_rel->ch = ch;
1342 ch->root_rel->expected_delay = MESH_RETRANSMIT_TIME;
1344 LOG (GNUNET_ERROR_TYPE_DEBUG, "CREATED CHANNEL %s\n", GMCH_2s (ch));
1346 /* Send create channel */
1348 struct GNUNET_MESH_ChannelCreate msgcc;
1350 msgcc.header.size = htons (sizeof (msgcc));
1351 msgcc.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE);
1352 msgcc.chid = htonl (ch->gid);
1353 msgcc.port = msg->port;
1354 msgcc.opt = msg->opt;
1356 GMT_queue_data (t, ch, &msgcc.header, GNUNET_YES);
1362 * Handler for mesh network payload traffic.
1364 * @param ch Channel for the message.
1365 * @param message Unencryted data message.
1366 * @param fwd Is this FWD traffic? GNUNET_YES : GNUNET_NO;
1369 GMCH_handle_data (struct MeshChannel *ch,
1370 const struct GNUNET_MESH_Data *msg,
1373 struct MeshChannelReliability *rel;
1374 struct MeshClient *c;
1377 /* Initialize FWD/BCK data */
1378 c = fwd ? ch->dest : ch->root;
1379 rel = fwd ? ch->dest_rel : ch->root_rel;
1387 GNUNET_STATISTICS_update (stats, "# data received", 1, GNUNET_NO);
1389 mid = ntohl (msg->mid);
1390 LOG (GNUNET_ERROR_TYPE_DEBUG, " mid %u\n", mid);
1392 if (GNUNET_NO == ch->reliable ||
1393 ( !GMC_is_pid_bigger (rel->mid_recv, mid) &&
1394 GMC_is_pid_bigger (rel->mid_recv + 64, mid) ) )
1396 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! RECV %u\n", mid);
1397 if (GNUNET_YES == ch->reliable)
1399 /* Is this the exact next expected messasge? */
1400 if (mid == rel->mid_recv)
1402 LOG (GNUNET_ERROR_TYPE_DEBUG, "as expected\n");
1404 send_client_data (ch, msg, fwd);
1408 LOG (GNUNET_ERROR_TYPE_DEBUG, "save for later\n");
1409 add_buffered_data (msg, rel);
1414 /* Tunnel is unreliable: send to clients directly */
1415 /* FIXME: accept Out Of Order traffic */
1416 rel->mid_recv = mid + 1;
1417 send_client_data (ch, msg, fwd);
1422 GNUNET_break_op (0);
1423 LOG (GNUNET_ERROR_TYPE_DEBUG,
1424 " MID %u not expected (%u - %u), dropping!\n",
1425 mid, rel->mid_recv, rel->mid_recv + 64);
1428 GMCH_send_data_ack (ch, fwd);
1433 * Handler for mesh network traffic end-to-end ACKs.
1435 * @param t Tunnel on which we got this message.
1436 * @param message Data message.
1437 * @param fwd Is this a fwd ACK? (dest->orig)
1440 GMCH_handle_data_ack (struct MeshChannel *ch,
1441 const struct GNUNET_MESH_DataACK *msg,
1444 struct MeshChannelReliability *rel;
1445 struct MeshReliableMessage *copy;
1446 struct MeshReliableMessage *next;
1450 ack = ntohl (msg->mid);
1451 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! %s ACK %u\n",
1452 (GNUNET_YES == fwd) ? "FWD" : "BCK", ack);
1454 if (GNUNET_YES == fwd)
1468 for (work = GNUNET_NO, copy = rel->head_sent; copy != NULL; copy = next)
1470 if (GMC_is_pid_bigger (copy->mid, ack))
1472 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! head %u, out!\n", copy->mid);
1473 channel_rel_free_sent (rel, msg);
1477 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! id %u\n", copy->mid);
1479 rel_message_free (copy);
1481 /* ACK client if needed */
1482 // channel_send_ack (t, type, GNUNET_MESSAGE_TYPE_MESH_UNICAST_ACK == type);
1484 /* If some message was free'd, update the retransmission delay*/
1485 if (GNUNET_YES == work)
1487 if (GNUNET_SCHEDULER_NO_TASK != rel->retry_task)
1489 GNUNET_SCHEDULER_cancel (rel->retry_task);
1490 if (NULL == rel->head_sent)
1492 rel->retry_task = GNUNET_SCHEDULER_NO_TASK;
1496 struct GNUNET_TIME_Absolute new_target;
1497 struct GNUNET_TIME_Relative delay;
1499 delay = GNUNET_TIME_relative_multiply (rel->retry_timer,
1500 MESH_RETRANSMIT_MARGIN);
1501 new_target = GNUNET_TIME_absolute_add (rel->head_sent->timestamp,
1503 delay = GNUNET_TIME_absolute_get_remaining (new_target);
1505 GNUNET_SCHEDULER_add_delayed (delay,
1506 &channel_retransmit_message,
1517 * Handler for channel create messages.
1519 * @param t Tunnel this channel will be in.
1520 * @param msg Message.
1521 * @param fwd Is this FWD traffic? GNUNET_YES : GNUNET_NO;
1523 struct MeshChannel *
1524 GMCH_handle_create (struct MeshTunnel3 *t,
1525 const struct GNUNET_MESH_ChannelCreate *msg,
1528 MESH_ChannelNumber chid;
1529 struct MeshChannel *ch;
1530 struct MeshClient *c;
1533 chid = ntohl (msg->chid);
1535 ch = GMT_get_channel (t, chid);
1538 /* Create channel */
1539 ch = channel_new (t, NULL, 0);
1542 channel_set_options (ch, ntohl (msg->opt));
1544 /* Find a destination client */
1545 port = ntohl (msg->port);
1546 LOG (GNUNET_ERROR_TYPE_DEBUG, " port %u\n", port);
1547 c = GML_client_get_by_port (port);
1550 /* TODO send reject */
1551 LOG (GNUNET_ERROR_TYPE_DEBUG, " no client has port registered\n");
1552 channel_destroy (ch);
1557 LOG (GNUNET_ERROR_TYPE_DEBUG, " client %p has port registered\n", c);
1560 add_destination (ch, c);
1561 if (GNUNET_YES == ch->reliable)
1562 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! Reliable\n");
1564 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! Not Reliable\n");
1566 GMCH_send_create (ch);
1567 channel_send_ack (ch, fwd);
1574 * Handler for channel ack messages.
1576 * @param ch Channel.
1577 * @param msg Message.
1578 * @param fwd Is this FWD traffic? GNUNET_YES : GNUNET_NO;
1581 GMCH_handle_ack (struct MeshChannel *ch,
1582 const struct GNUNET_MESH_ChannelManage *msg,
1585 channel_confirm (ch, !fwd);
1590 * Handler for channel destroy messages.
1592 * @param ch Channel to be destroyed of.
1593 * @param msg Message.
1594 * @param fwd Is this FWD traffic? GNUNET_YES : GNUNET_NO;
1597 GMCH_handle_destroy (struct MeshChannel *ch,
1598 const struct GNUNET_MESH_ChannelManage *msg,
1601 struct MeshTunnel3 *t;
1604 if ( (fwd && NULL == ch->dest) || (!fwd && NULL == ch->root) )
1606 /* Not for us (don't destroy twice a half-open loopback channel) */
1611 GMCH_send_destroy (ch);
1612 channel_destroy (ch);
1613 GMT_destroy_if_empty (t);
1618 * Sends an already built message on a channel.
1620 * If the channel is on a loopback tunnel, notifies the appropriate destination
1623 * On a normal channel passes the message to the tunnel for encryption and
1624 * sending on a connection.
1626 * This function DOES NOT save the message for retransmission.
1628 * @param message Message to send. Function makes a copy of it.
1629 * @param ch Channel on which this message is transmitted.
1630 * @param fwd Is this a fwd message?
1633 GMCH_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
1634 struct MeshChannel *ch, int fwd)
1636 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMCH Send %s %s on channel %s\n",
1637 fwd ? "FWD" : "BCK", GNUNET_MESH_DEBUG_M2S (ntohs (message->type)),
1640 if (GMT_is_loopback (ch->t))
1642 handle_loopback (ch, message, fwd);
1646 GMT_send_prebuilt_message (message, ch->t, ch, fwd);
1651 * Get the static string for identification of the channel.
1653 * @param ch Channel.
1655 * @return Static string with the channel IDs.
1658 GMCH_2s (const struct MeshChannel *ch)
1660 static char buf[64];
1663 return "(NULL Channel)";
1665 sprintf (buf, "%s:%X (%X / %X)",
1666 GMT_2s (ch->t), ch->gid, ch->lid_root, ch->lid_dest);