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");
330 * Send data to a client.
332 * If the client is ready, send directly, otherwise buffer while listening
336 * @param msg Message.
337 * @param fwd Is this a fwd (root->dest) message?
340 send_client_data (struct MeshChannel *ch,
341 const struct GNUNET_MESH_Data *msg,
346 if (ch->dest_rel->client_ready)
347 GML_send_data (ch->dest, msg, ch->lid_dest);
349 add_buffered_data (msg, ch->dest_rel);
353 if (ch->root_rel->client_ready)
354 GML_send_data (ch->root, msg, ch->lid_root);
356 add_buffered_data (msg, ch->root_rel);
362 * Add a client to a channel, initializing all needed data structures.
364 * @param ch Channel to which add the client.
365 * @param c Client which to add to the channel.
368 GMCH_add_client (struct MeshChannel *ch, struct MeshClient *c)
370 if (NULL != ch->dest)
376 /* Assign local id as destination */
377 ch->lid_dest = GML_get_next_chid (c);
379 /* Store in client's hashmap */
380 GML_channel_add (c, ch->lid_dest, ch);
382 GNUNET_break (NULL == ch->dest_rel);
383 ch->dest_rel = GNUNET_new (struct MeshChannelReliability);
384 ch->dest_rel->ch = ch;
385 ch->dest_rel->expected_delay = MESH_RETRANSMIT_TIME;
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 the ACK fwd?
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 CREATE message sent fwd?
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 channel_send_ack (ch, fwd);
660 * Save a copy to retransmit in case it gets lost.
662 * Initializes all needed callbacks and timers.
664 * @param ch Channel this message goes on.
665 * @param msg Message to copy.
666 * @param fwd Is this fwd traffic?
669 channel_save_copy (struct MeshChannel *ch,
670 const struct GNUNET_MessageHeader *msg,
673 struct MeshChannelReliability *rel;
674 struct MeshReliableMessage *copy;
679 rel = fwd ? ch->root_rel : ch->dest_rel;
681 type = ntohs (msg->type);
682 size = ntohs (msg->size);
684 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! SAVE %u\n", mid);
685 copy = GNUNET_malloc (sizeof (struct MeshReliableMessage) + size);
687 copy->timestamp = GNUNET_TIME_absolute_get ();
690 memcpy (©[1], msg, size);
692 LOG (GNUNET_ERROR_TYPE_DEBUG, " n_sent %u\n", rel->n_sent);
693 GNUNET_CONTAINER_DLL_insert_tail (rel->head_sent, rel->tail_sent, copy);
694 if (GNUNET_SCHEDULER_NO_TASK == rel->retry_task)
697 GNUNET_TIME_relative_multiply (rel->expected_delay,
698 MESH_RETRANSMIT_MARGIN);
700 GNUNET_SCHEDULER_add_delayed (rel->retry_timer,
701 &channel_retransmit_message,
709 * Send a buffered message to the client, for in order delivery or
710 * as result of client ACK.
712 * @param ch Channel on which to empty the message buffer.
713 * @param c Client to send to.
714 * @param fwd Is this to send FWD data?.
717 send_client_buffered_data (struct MeshChannel *ch,
718 struct MeshClient *c,
721 struct MeshReliableMessage *copy;
722 struct MeshChannelReliability *rel;
724 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_buffered_data\n");
725 rel = fwd ? ch->dest_rel : ch->root_rel;
726 if (GNUNET_NO == rel->client_ready)
728 LOG (GNUNET_ERROR_TYPE_DEBUG, "client not ready\n");
732 copy = rel->head_recv;
733 /* We never buffer channel management messages */
736 if (copy->mid == rel->mid_recv || GNUNET_NO == ch->reliable)
738 struct GNUNET_MESH_Data *msg = (struct GNUNET_MESH_Data *) ©[1];
740 LOG (GNUNET_ERROR_TYPE_DEBUG,
741 " have %u! now expecting %u\n",
742 copy->mid, rel->mid_recv + 1);
743 send_client_data (ch, msg, fwd);
746 GNUNET_CONTAINER_DLL_remove (rel->head_recv, rel->tail_recv, copy);
751 LOG (GNUNET_ERROR_TYPE_DEBUG,
752 " reliable && don't have %u, next is %u\n",
758 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_buffered_data END\n");
765 * Destroy a channel and free all resources.
767 * @param ch Channel to destroy.
770 channel_destroy (struct MeshChannel *ch)
772 struct MeshClient *c;
777 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying channel %s:%u\n",
778 GMT_2s (ch->t), ch->gid);
784 GML_channel_remove (c, ch->lid_root, ch);
790 GML_channel_remove (c, ch->lid_dest, ch);
793 channel_rel_free_all (ch->root_rel);
794 channel_rel_free_all (ch->dest_rel);
796 GMT_remove_channel (ch->t, ch);
797 GNUNET_STATISTICS_update (stats, "# channels", -1, GNUNET_NO);
804 * Create a new channel.
806 * @param t Tunnel this channel is in.
807 * @param owner Client that owns the channel, NULL for foreign channels.
808 * @param lid_root Local ID for root client.
810 * @return A new initialized channel. NULL on error.
812 static struct MeshChannel *
813 channel_new (struct MeshTunnel3 *t,
814 struct MeshClient *owner,
815 MESH_ChannelNumber lid_root)
817 struct MeshChannel *ch;
819 ch = GNUNET_new (struct MeshChannel);
821 ch->lid_root = lid_root;
824 GNUNET_STATISTICS_update (stats, "# channels", 1, GNUNET_NO);
828 ch->gid = GMT_get_next_chid (t);
829 GML_channel_add (owner, lid_root, ch);
831 GMT_add_channel (t, ch);
838 * Set options in a channel, extracted from a bit flag field
840 * @param ch Channel to set options to.
841 * @param options Bit array in host byte order.
844 channel_set_options (struct MeshChannel *ch, uint32_t options)
846 ch->nobuffer = (options & GNUNET_MESH_OPTION_NOBUFFER) != 0 ?
847 GNUNET_YES : GNUNET_NO;
848 ch->reliable = (options & GNUNET_MESH_OPTION_RELIABLE) != 0 ?
849 GNUNET_YES : GNUNET_NO;
854 * Handle a loopback message: call the appropriate handler for the message type.
856 * @param ch Channel this message is on.
857 * @param msgh Message header.
858 * @param fwd Is this FWD traffic?
861 handle_loopback (struct MeshChannel *ch,
862 const struct GNUNET_MessageHeader *msgh,
867 type = ntohs (msgh->type);
868 LOG (GNUNET_ERROR_TYPE_DEBUG,
869 "Loopback %s message!\n",
870 GNUNET_MESH_DEBUG_M2S (type));
874 case GNUNET_MESSAGE_TYPE_MESH_DATA:
875 /* Don't send hop ACK, wait for client to ACK */
876 GMCH_handle_data (ch, (struct GNUNET_MESH_Data *) msgh, fwd);
879 case GNUNET_MESSAGE_TYPE_MESH_DATA_ACK:
880 GMCH_handle_data_ack (ch, (struct GNUNET_MESH_DataACK *) msgh, fwd);
883 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE:
884 GMCH_handle_create (ch->t,
885 (struct GNUNET_MESH_ChannelCreate *) msgh,
889 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_ACK:
891 (struct GNUNET_MESH_ChannelManage *) msgh,
895 case GNUNET_MESSAGE_TYPE_MESH_CHANNEL_DESTROY:
896 GMCH_handle_destroy (ch,
897 (struct GNUNET_MESH_ChannelManage *) msgh,
903 LOG (GNUNET_ERROR_TYPE_DEBUG,
904 "end-to-end message not known (%u)\n",
911 /******************************************************************************/
912 /******************************** API ***********************************/
913 /******************************************************************************/
923 GMCH_get_id (const struct MeshChannel *ch)
930 * Get the channel tunnel.
932 * @param ch Channel to get the tunnel from.
934 * @return tunnel of the channel.
937 GMCH_get_tunnel (const struct MeshChannel *ch)
944 * Get free buffer space towards the client on a specific channel.
947 * @param fwd Is query about FWD traffic?
949 * @return Free buffer space [0 - 64]
952 GMCH_get_buffer (struct MeshChannel *ch, int fwd)
954 struct MeshChannelReliability *rel;
956 rel = fwd ? ch->dest_rel : ch->root_rel;
958 /* If rel is NULL it means that the end is not yet created,
959 * most probably is a loopback channel at the point of sending
960 * the ChannelCreate to itself.
965 return (64 - rel->n_recv);
970 * Is the root client for this channel on this peer?
973 * @param fwd Is this for fwd traffic?
975 * @return GNUNET_YES in case it is.
978 GMCH_is_origin (struct MeshChannel *ch, int fwd)
980 struct MeshClient *c;
982 c = fwd ? ch->root : ch->dest;
988 * Is the destination client for this channel on this peer?
991 * @param fwd Is this for fwd traffic?
993 * @return GNUNET_YES in case it is.
996 GMCH_is_terminal (struct MeshChannel *ch, int fwd)
998 struct MeshClient *c;
1000 c = fwd ? ch->dest : ch->root;
1006 * Notify the destination client that a new incoming channel was created.
1008 * @param ch Channel that was created.
1011 GMCH_send_create (struct MeshChannel *ch)
1015 if (NULL == ch->dest)
1019 opt |= GNUNET_YES == ch->reliable ? GNUNET_MESH_OPTION_RELIABLE : 0;
1020 opt |= GNUNET_YES == ch->nobuffer ? GNUNET_MESH_OPTION_NOBUFFER : 0;
1021 GML_send_channel_create (ch->dest, ch->lid_dest, ch->port, opt,
1022 GMT_get_destination (ch->t));
1027 * Notify a client that the channel is no longer valid.
1028 * FIXME send on tunnel if some client == NULL?
1030 * @param ch Channel that is destroyed.
1033 GMCH_send_destroy (struct MeshChannel *ch)
1035 if (NULL != ch->root)
1036 GML_send_channel_destroy (ch->root, ch->lid_root);
1038 if (NULL != ch->dest)
1039 GML_send_channel_destroy (ch->dest, ch->lid_dest);
1044 * Send data on a channel.
1046 * If the destination is local, send it to client, otherwise encrypt and
1050 * @param msg Message.
1051 * @param fwd Is this a fwd (root->dest) message?
1054 GMCH_send_data (struct MeshChannel *ch,
1055 const struct GNUNET_MESH_Data *msg,
1058 if (GMCH_is_terminal (ch, fwd))
1060 GML_send_data (fwd ? ch->dest : ch->root,
1062 fwd ? ch->lid_dest : ch->lid_root);
1066 GMT_send_prebuilt_message (&msg->header, ch->t, ch, fwd);
1072 * Send an end-to-end ACK message for the most recent in-sequence payload.
1074 * If channel is not reliable, do nothing.
1076 * @param ch Channel this is about.
1077 * @param fwd Is for FWD traffic? (ACK dest->owner)
1080 GMCH_send_data_ack (struct MeshChannel *ch, int fwd)
1082 struct GNUNET_MESH_DataACK msg;
1083 struct MeshChannelReliability *rel;
1084 struct MeshReliableMessage *copy;
1089 if (GNUNET_NO == ch->reliable)
1093 rel = fwd ? ch->dest_rel : ch->root_rel;
1094 LOG (GNUNET_ERROR_TYPE_DEBUG,
1095 "send_data_ack for %u\n",
1098 type = GNUNET_MESSAGE_TYPE_MESH_DATA_ACK;
1099 msg.header.type = htons (type);
1100 msg.header.size = htons (sizeof (msg));
1101 msg.chid = htonl (ch->gid);
1102 msg.mid = htonl (rel->mid_recv - 1);
1104 for (copy = rel->head_recv; NULL != copy; copy = copy->next)
1106 if (copy->type != type)
1108 delta = copy->mid - rel->mid_recv;
1111 mask = 0x1LL << delta;
1112 msg.futures |= mask;
1113 LOG (GNUNET_ERROR_TYPE_DEBUG,
1114 " setting bit for %u (delta %u) (%llX) -> %llX\n",
1115 copy->mid, delta, mask, msg.futures);
1117 LOG (GNUNET_ERROR_TYPE_DEBUG, " final futures %llX\n", msg.futures);
1119 GMCH_send_prebuilt_message (&msg.header, ch, fwd);
1120 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_data_ack END\n");
1127 * @param ch Channel.
1130 GMCH_debug (struct MeshChannel *ch)
1134 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CHANNEL ***\n");
1137 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %s:%X (%p)\n",
1138 GMT_2s (ch->t), ch->gid, ch);
1139 LOG (GNUNET_ERROR_TYPE_DEBUG, " root %p/%p\n",
1140 ch->root, ch->root_rel);
1141 if (NULL != ch->root)
1143 LOG (GNUNET_ERROR_TYPE_DEBUG, " cli %s\n", GML_2s (ch->root));
1144 LOG (GNUNET_ERROR_TYPE_DEBUG, " ready %s\n",
1145 ch->root_rel->client_ready ? "YES" : "NO");
1146 LOG (GNUNET_ERROR_TYPE_DEBUG, " id %X\n", ch->lid_root);
1148 LOG (GNUNET_ERROR_TYPE_DEBUG, " dest %p/%p\n",
1149 ch->dest, ch->dest_rel);
1150 if (NULL != ch->dest)
1152 LOG (GNUNET_ERROR_TYPE_DEBUG, " cli %s\n", GML_2s (ch->dest));
1153 LOG (GNUNET_ERROR_TYPE_DEBUG, " ready %s\n",
1154 ch->dest_rel->client_ready ? "YES" : "NO");
1155 LOG (GNUNET_ERROR_TYPE_DEBUG, " id %X\n", ch->lid_dest);
1161 * Handle an ACK given by a client.
1163 * Mark client as ready and send him any buffered data we could have for him.
1165 * @param ch Channel.
1166 * @param fwd Is this a "FWD ACK"? (FWD ACKs are sent by root and go BCK)
1169 GMCH_handle_local_ack (struct MeshChannel *ch, int fwd)
1171 struct MeshChannelReliability *rel;
1172 struct MeshClient *c;
1174 rel = fwd ? ch->dest_rel : ch->root_rel;
1175 c = fwd ? ch->dest : ch->root;
1177 rel->client_ready = GNUNET_YES;
1178 send_client_buffered_data (ch, c, fwd);
1179 GMC_send_ack (NULL, ch, fwd);
1184 * Handle data given by a client.
1186 * Check whether the client is allowed to send in this tunnel, save if channel
1187 * is reliable and send an ACK to the client if there is still buffer space
1190 * @param ch Channel.
1191 * @param fwd Is this a FWD data?
1193 * @return GNUNET_OK if everything goes well, GNUNET_SYSERR in case of en error.
1196 GMCH_handle_local_data (struct MeshChannel *ch,
1197 struct MeshClient *c,
1198 struct GNUNET_MessageHeader *message,
1201 struct MeshChannelReliability *rel;
1202 struct GNUNET_MESH_Data *payload;
1203 size_t size = ntohs (message->size);
1204 uint16_t p2p_size = sizeof(struct GNUNET_MESH_Data) + size;
1205 unsigned char cbuf[p2p_size];
1207 /* Is the client in the channel? */
1215 return GNUNET_SYSERR;
1218 rel = fwd ? ch->root_rel : ch->dest_rel;
1220 /* Ok, everything is correct, send the message. */
1221 payload = (struct GNUNET_MESH_Data *) cbuf;
1222 payload->mid = htonl (rel->mid_send);
1224 memcpy (&payload[1], message, size);
1225 payload->header.size = htons (p2p_size);
1226 payload->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_DATA);
1227 payload->chid = htonl (ch->gid);
1228 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channel...\n");
1229 GMCH_send_prebuilt_message (&payload->header, ch, fwd);
1231 if (GNUNET_YES == ch->reliable)
1232 channel_save_copy (ch, &payload->header, fwd);
1233 if (GMT_get_buffer (ch->t, fwd) > 0)
1234 GML_send_ack (c, fwd ? ch->lid_root : ch->lid_dest);
1241 * Handle a channel destroy requested by a client.
1243 * Destroy the channel and the tunnel in case this was the last channel.
1245 * @param ch Channel.
1246 * @param c Client that requested the destruction (to avoid notifying him).
1249 GMCH_handle_local_destroy (struct MeshChannel *ch,
1250 struct MeshClient *c)
1252 struct MeshTunnel3 *t;
1254 /* Cleanup after the tunnel */
1257 LOG (GNUNET_ERROR_TYPE_DEBUG, " Client %s is destination.\n", GML_2s (c));
1258 GML_client_delete_channel (c, ch, ch->lid_dest);
1263 LOG (GNUNET_ERROR_TYPE_DEBUG, " Client %s is owner.\n", GML_2s (c));
1264 GML_client_delete_channel (c, ch, ch->lid_root);
1269 GMCH_send_destroy (ch);
1270 channel_destroy (ch);
1271 GMT_destroy_if_empty (t);
1276 * Handle a channel create requested by a client.
1278 * Create the channel and the tunnel in case this was the first0 channel.
1280 * @param c Client that requested the creation (will be the root).
1281 * @param msg Create Channel message.
1283 * @return GNUNET_OK if everything went fine, GNUNET_SYSERR otherwise.
1286 GMCH_handle_local_create (struct MeshClient *c,
1287 struct GNUNET_MESH_ChannelMessage *msg)
1289 struct MeshChannel *ch;
1290 struct MeshTunnel3 *t;
1291 struct MeshPeer *peer;
1292 MESH_ChannelNumber chid;
1294 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s:%u\n",
1295 GNUNET_i2s (&msg->peer), ntohl (msg->port));
1296 chid = ntohl (msg->channel_id);
1298 /* Sanity check for duplicate channel IDs */
1299 if (NULL != GML_channel_get (c, chid))
1302 return GNUNET_SYSERR;
1305 peer = GMP_get (&msg->peer);
1306 GMP_add_tunnel (peer);
1307 t = GMP_get_tunnel (peer);
1309 if (GMP_get_short_id (peer) == myid)
1311 GMT_change_state (t, MESH_TUNNEL3_READY);
1318 /* Create channel */
1319 ch = channel_new (t, c, chid);
1323 return GNUNET_SYSERR;
1325 ch->port = ntohl (msg->port);
1326 channel_set_options (ch, ntohl (msg->opt));
1328 /* In unreliable channels, we'll use the DLL to buffer BCK data */
1329 ch->root_rel = GNUNET_new (struct MeshChannelReliability);
1330 ch->root_rel->ch = ch;
1331 ch->root_rel->expected_delay = MESH_RETRANSMIT_TIME;
1333 LOG (GNUNET_ERROR_TYPE_DEBUG, "CREATED CHANNEL %s\n", GMCH_2s (ch));
1335 /* Send create channel */
1337 struct GNUNET_MESH_ChannelCreate msgcc;
1339 msgcc.header.size = htons (sizeof (msgcc));
1340 msgcc.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_CHANNEL_CREATE);
1341 msgcc.chid = htonl (ch->gid);
1342 msgcc.port = msg->port;
1343 msgcc.opt = msg->opt;
1345 GMT_queue_data (t, ch, &msgcc.header, GNUNET_YES);
1351 * Handler for mesh network payload traffic.
1353 * @param ch Channel for the message.
1354 * @param message Unencryted data message.
1355 * @param fwd Is this FWD traffic? GNUNET_YES : GNUNET_NO;
1358 GMCH_handle_data (struct MeshChannel *ch,
1359 const struct GNUNET_MESH_Data *msg,
1362 struct MeshChannelReliability *rel;
1363 struct MeshClient *c;
1366 /* Initialize FWD/BCK data */
1367 c = fwd ? ch->dest : ch->root;
1368 rel = fwd ? ch->dest_rel : ch->root_rel;
1376 GNUNET_STATISTICS_update (stats, "# data received", 1, GNUNET_NO);
1378 mid = ntohl (msg->mid);
1379 LOG (GNUNET_ERROR_TYPE_DEBUG, " mid %u\n", mid);
1381 if (GNUNET_NO == ch->reliable ||
1382 ( !GMC_is_pid_bigger (rel->mid_recv, mid) &&
1383 GMC_is_pid_bigger (rel->mid_recv + 64, mid) ) )
1385 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! RECV %u\n", mid);
1386 if (GNUNET_YES == ch->reliable)
1388 /* Is this the exact next expected messasge? */
1389 if (mid == rel->mid_recv)
1391 LOG (GNUNET_ERROR_TYPE_DEBUG, "as expected\n");
1393 send_client_data (ch, msg, fwd);
1397 LOG (GNUNET_ERROR_TYPE_DEBUG, "save for later\n");
1398 add_buffered_data (msg, rel);
1403 /* Tunnel is unreliable: send to clients directly */
1404 /* FIXME: accept Out Of Order traffic */
1405 rel->mid_recv = mid + 1;
1406 send_client_data (ch, msg, fwd);
1411 GNUNET_break_op (0);
1412 LOG (GNUNET_ERROR_TYPE_DEBUG,
1413 " MID %u not expected (%u - %u), dropping!\n",
1414 mid, rel->mid_recv, rel->mid_recv + 64);
1417 GMCH_send_data_ack (ch, fwd);
1422 * Handler for mesh network traffic end-to-end ACKs.
1424 * @param t Tunnel on which we got this message.
1425 * @param message Data message.
1426 * @param fwd Is this a fwd ACK? (dest->orig)
1429 GMCH_handle_data_ack (struct MeshChannel *ch,
1430 const struct GNUNET_MESH_DataACK *msg,
1433 struct MeshChannelReliability *rel;
1434 struct MeshReliableMessage *copy;
1435 struct MeshReliableMessage *next;
1439 ack = ntohl (msg->mid);
1440 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! %s ACK %u\n",
1441 (GNUNET_YES == fwd) ? "FWD" : "BCK", ack);
1443 if (GNUNET_YES == fwd)
1457 for (work = GNUNET_NO, copy = rel->head_sent; copy != NULL; copy = next)
1459 if (GMC_is_pid_bigger (copy->mid, ack))
1461 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! head %u, out!\n", copy->mid);
1462 channel_rel_free_sent (rel, msg);
1466 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! id %u\n", copy->mid);
1468 rel_message_free (copy);
1470 /* ACK client if needed */
1471 // channel_send_ack (t, type, GNUNET_MESSAGE_TYPE_MESH_UNICAST_ACK == type);
1473 /* If some message was free'd, update the retransmission delay*/
1474 if (GNUNET_YES == work)
1476 if (GNUNET_SCHEDULER_NO_TASK != rel->retry_task)
1478 GNUNET_SCHEDULER_cancel (rel->retry_task);
1479 if (NULL == rel->head_sent)
1481 rel->retry_task = GNUNET_SCHEDULER_NO_TASK;
1485 struct GNUNET_TIME_Absolute new_target;
1486 struct GNUNET_TIME_Relative delay;
1488 delay = GNUNET_TIME_relative_multiply (rel->retry_timer,
1489 MESH_RETRANSMIT_MARGIN);
1490 new_target = GNUNET_TIME_absolute_add (rel->head_sent->timestamp,
1492 delay = GNUNET_TIME_absolute_get_remaining (new_target);
1494 GNUNET_SCHEDULER_add_delayed (delay,
1495 &channel_retransmit_message,
1506 * Handler for channel create messages.
1508 * @param t Tunnel this channel will be in.
1509 * @param msg Message.
1510 * @param fwd Is this FWD traffic? GNUNET_YES : GNUNET_NO;
1512 struct MeshChannel *
1513 GMCH_handle_create (struct MeshTunnel3 *t,
1514 const struct GNUNET_MESH_ChannelCreate *msg,
1517 MESH_ChannelNumber chid;
1518 struct MeshChannel *ch;
1519 struct MeshClient *c;
1522 chid = ntohl (msg->chid);
1524 /* Create channel */
1525 ch = channel_new (t, NULL, 0);
1527 channel_set_options (ch, ntohl (msg->opt));
1529 /* Find a destination client */
1530 port = ntohl (msg->port);
1531 LOG (GNUNET_ERROR_TYPE_DEBUG, " port %u\n", port);
1532 c = GML_client_get_by_port (port);
1535 /* TODO send reject */
1536 LOG (GNUNET_ERROR_TYPE_DEBUG, " no client has port registered\n");
1537 channel_destroy (ch);
1541 GMCH_add_client (ch, c);
1542 if (GNUNET_YES == ch->reliable)
1543 LOG (GNUNET_ERROR_TYPE_DEBUG, "!!! Reliable\n");
1545 GMCH_send_create (ch);
1546 GMCH_send_data_ack (ch, fwd);
1547 channel_send_ack (ch, !fwd);
1549 if (GNUNET_NO == ch->dest_rel->client_ready)
1551 GML_send_ack (ch->dest, ch->lid_dest);
1552 ch->dest_rel->client_ready = GNUNET_YES;
1560 * Handler for channel ack messages.
1562 * @param ch Channel.
1563 * @param msg Message.
1564 * @param fwd Is this FWD traffic? GNUNET_YES : GNUNET_NO;
1567 GMCH_handle_ack (struct MeshChannel *ch,
1568 const struct GNUNET_MESH_ChannelManage *msg,
1571 channel_confirm (ch, !fwd);
1576 * Handler for channel destroy messages.
1578 * @param ch Channel to be destroyed of.
1579 * @param msg Message.
1580 * @param fwd Is this FWD traffic? GNUNET_YES : GNUNET_NO;
1583 GMCH_handle_destroy (struct MeshChannel *ch,
1584 const struct GNUNET_MESH_ChannelManage *msg,
1587 struct MeshTunnel3 *t;
1590 if ( (fwd && NULL == ch->dest) || (!fwd && NULL == ch->root) )
1592 /* Not for us (don't destroy twice a half-open loopback channel) */
1597 GMCH_send_destroy (ch);
1598 channel_destroy (ch);
1599 GMT_destroy_if_empty (t);
1604 * Sends an already built message on a channel.
1606 * If the channel is on a loopback tunnel, notifies the appropriate destination
1609 * On a normal channel passes the message to the tunnel for encryption and
1610 * sending on a connection.
1612 * This function DOES NOT save the message for retransmission.
1614 * @param message Message to send. Function makes a copy of it.
1615 * @param ch Channel on which this message is transmitted.
1616 * @param fwd Is this a fwd message?
1619 GMCH_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
1620 struct MeshChannel *ch, int fwd)
1622 LOG (GNUNET_ERROR_TYPE_DEBUG, "Send on Channel %s:%X %s\n",
1623 GMT_2s (ch->t), ch->gid, fwd ? "FWD" : "BCK");
1624 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s\n",
1625 GNUNET_MESH_DEBUG_M2S (ntohs (message->type)));
1627 if (GMT_is_loopback (ch->t))
1629 handle_loopback (ch, message, fwd);
1633 GMT_send_prebuilt_message (message, ch->t, ch, fwd);
1638 * Get the static string for identification of the channel.
1640 * @param ch Channel.
1642 * @return Static string with the channel IDs.
1645 GMCH_2s (const struct MeshChannel *ch)
1647 static char buf[64];
1650 return "(NULL Channel)";
1652 sprintf (buf, "%s:%X (%X / %X)",
1653 GMT_2s (ch->t), ch->gid, ch->lid_root, ch->lid_dest);