2 This file is part of GNUnet.
3 Copyright (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., 51 Franklin Street, Fifth Floor,
18 Boston, MA 02110-1301, USA.
23 #include "gnunet_util_lib.h"
25 #include "gnunet_statistics_service.h"
28 #include "cadet_protocol.h"
30 #include "gnunet-service-cadet_channel.h"
31 #include "gnunet-service-cadet_local.h"
32 #include "gnunet-service-cadet_tunnel.h"
33 #include "gnunet-service-cadet_peer.h"
35 #define LOG(level, ...) GNUNET_log_from(level,"cadet-chn",__VA_ARGS__)
37 #define CADET_RETRANSMIT_TIME GNUNET_TIME_relative_multiply(\
38 GNUNET_TIME_UNIT_MILLISECONDS, 250)
39 #define CADET_RETRANSMIT_MARGIN 4
43 * All the states a connection can be in.
45 enum CadetChannelState
48 * Uninitialized status, should never appear in operation.
53 * Connection create message sent, waiting for ACK.
58 * Connection confirmed, ready to carry traffic.
65 * Info holder for channel messages in queues.
67 struct CadetChannelQueue
72 struct CadetTunnelQueue *tq;
75 * Message type (DATA/DATA_ACK)
80 * Message copy (for DATAs, to start retransmission timer)
82 struct CadetReliableMessage *copy;
85 * Reliability (for DATA_ACKs, to access rel->ack_q)
87 struct CadetChannelReliability *rel;
92 * Info needed to retry a message in case it gets lost.
94 struct CadetReliableMessage
97 * Double linked list, FIFO style
99 struct CadetReliableMessage *next;
100 struct CadetReliableMessage *prev;
103 * Type of message (payload, channel management).
108 * Tunnel Reliability queue this message is in.
110 struct CadetChannelReliability *rel;
113 * ID of the message (ACK needed to free)
120 struct CadetChannelQueue *chq;
123 * When was this message issued (to calculate ACK delay)
125 struct GNUNET_TIME_Absolute timestamp;
127 /* struct GNUNET_CADET_Data with payload */
132 * Info about the traffic state for a client in a channel.
134 struct CadetChannelReliability
137 * Channel this is about.
139 struct CadetChannel *ch;
142 * DLL of messages sent and not yet ACK'd.
144 struct CadetReliableMessage *head_sent;
145 struct CadetReliableMessage *tail_sent;
148 * DLL of messages received out of order.
150 struct CadetReliableMessage *head_recv;
151 struct CadetReliableMessage *tail_recv;
159 * Next MID to use for outgoing traffic.
164 * Next MID expected for incoming traffic.
169 * Handle for queued unique data CREATE, DATA_ACK.
171 struct CadetChannelQueue *uniq;
174 * Can we send data to the client?
179 * Can the client send data to us?
184 * Task to resend/poll in case no ACK is received.
186 struct GNUNET_SCHEDULER_Task * retry_task;
189 * Counter for exponential backoff.
191 struct GNUNET_TIME_Relative retry_timer;
194 * How long does it usually take to get an ACK.
196 struct GNUNET_TIME_Relative expected_delay;
201 * Struct containing all information regarding a channel to a remote client.
206 * Tunnel this channel is in.
208 struct CadetTunnel *t;
211 * Destination port of the channel.
216 * Global channel number ( < GNUNET_CADET_LOCAL_CHANNEL_ID_CLI)
218 CADET_ChannelNumber gid;
221 * Local tunnel number for root (owner) client.
222 * ( >= GNUNET_CADET_LOCAL_CHANNEL_ID_CLI or 0 )
224 CADET_ChannelNumber lid_root;
227 * Local tunnel number for local destination clients (incoming number)
228 * ( >= GNUNET_CADET_LOCAL_CHANNEL_ID_SERV or 0).
230 CADET_ChannelNumber lid_dest;
235 enum CadetChannelState state;
238 * Is the tunnel bufferless (minimum latency)?
243 * Is the tunnel reliable?
248 * Last time the channel was used
250 struct GNUNET_TIME_Absolute timestamp;
253 * Client owner of the tunnel, if any
255 struct CadetClient *root;
258 * Client destination of the tunnel, if any.
260 struct CadetClient *dest;
263 * Flag to signal the destruction of the channel.
264 * If this is set GNUNET_YES the channel will be destroyed
265 * when the queue is empty.
270 * Total (reliable) messages pending ACK for this channel.
272 unsigned int pending_messages;
276 * Only present (non-NULL) at the owner of a tunnel.
278 struct CadetChannelReliability *root_rel;
282 * Only present (non-NULL) at the destination of a tunnel.
284 struct CadetChannelReliability *dest_rel;
289 /******************************************************************************/
290 /******************************* GLOBALS ***********************************/
291 /******************************************************************************/
294 * Global handle to the statistics service.
296 extern struct GNUNET_STATISTICS_Handle *stats;
299 * Local peer own ID (memory efficient handle).
301 extern GNUNET_PEER_Id myid;
304 /******************************************************************************/
305 /******************************** STATIC ***********************************/
306 /******************************************************************************/
310 * Destroy a reliable message after it has been acknowledged, either by
311 * direct mid ACK or bitfield. Updates the appropriate data structures and
312 * timers and frees all memory.
314 * @param copy Message that is no longer needed: remote peer got it.
315 * @param update_time Is the timing information relevant?
316 * If this message is ACK in a batch the timing information
317 * is skewed by the retransmission, count only for the
318 * retransmitted message.
320 * @return #GNUNET_YES if channel was destroyed as a result of the call,
321 * #GNUNET_NO otherwise.
324 rel_message_free (struct CadetReliableMessage *copy, int update_time);
327 * send a channel create message.
329 * @param ch Channel for which to send.
332 send_create (struct CadetChannel *ch);
335 * Confirm we got a channel create, FWD ack.
337 * @param ch The channel to confirm.
338 * @param fwd Should we send a FWD ACK? (going dest->root)
341 send_ack (struct CadetChannel *ch, int fwd);
346 * Test if the channel is loopback: both root and dest are on the local peer.
348 * @param ch Channel to test.
350 * @return #GNUNET_YES if channel is loopback, #GNUNET_NO otherwise.
353 is_loopback (const struct CadetChannel *ch)
356 return GCT_is_loopback (ch->t);
358 return (NULL != ch->root && NULL != ch->dest);
363 * Save a copy of the data message for later retransmission.
365 * @param msg Message to copy.
366 * @param mid Message ID.
367 * @param rel Reliability data for retransmission.
369 static struct CadetReliableMessage *
370 copy_message (const struct GNUNET_CADET_Data *msg, uint32_t mid,
371 struct CadetChannelReliability *rel)
373 struct CadetReliableMessage *copy;
376 size = ntohs (msg->header.size);
377 copy = GNUNET_malloc (sizeof (*copy) + size);
380 copy->type = GNUNET_MESSAGE_TYPE_CADET_DATA;
381 memcpy (©[1], msg, size);
387 * We have received a message out of order, or the client is not ready.
388 * Buffer it until we receive an ACK from the client or the missing
389 * message from the channel.
391 * @param msg Message to buffer (MUST be of type CADET_DATA).
392 * @param rel Reliability data to the corresponding direction.
395 add_buffered_data (const struct GNUNET_CADET_Data *msg,
396 struct CadetChannelReliability *rel)
398 struct CadetReliableMessage *copy;
399 struct CadetReliableMessage *prev;
402 mid = ntohl (msg->mid);
404 LOG (GNUNET_ERROR_TYPE_DEBUG, "add_buffered_data MID %u (%u)\n",
409 // FIXME do something better than O(n), although n < 64...
410 // FIXME start from the end (most messages are the latest ones)
411 for (prev = rel->head_recv; NULL != prev; prev = prev->next)
413 LOG (GNUNET_ERROR_TYPE_DEBUG, " prev %u\n", prev->mid);
414 if (prev->mid == mid)
416 LOG (GNUNET_ERROR_TYPE_DEBUG, " already there!\n");
420 else if (GC_is_pid_bigger (prev->mid, mid))
422 LOG (GNUNET_ERROR_TYPE_DEBUG, " bingo!\n");
423 copy = copy_message (msg, mid, rel);
424 GNUNET_CONTAINER_DLL_insert_before (rel->head_recv, rel->tail_recv,
429 copy = copy_message (msg, mid, rel);
430 LOG (GNUNET_ERROR_TYPE_DEBUG, " insert at tail! (now: %u)\n", rel->n_recv);
431 GNUNET_CONTAINER_DLL_insert_tail (rel->head_recv, rel->tail_recv, copy);
432 LOG (GNUNET_ERROR_TYPE_DEBUG, "add_buffered_data END\n");
437 * Add a destination client to a channel, initializing all data structures
438 * in the channel and the client.
440 * @param ch Channel to which add the destination.
441 * @param c Client which to add to the channel.
444 add_destination (struct CadetChannel *ch, struct CadetClient *c)
446 if (NULL != ch->dest)
452 /* Assign local id as destination */
453 ch->lid_dest = GML_get_next_chid (c);
455 /* Store in client's hashmap */
456 GML_channel_add (c, ch->lid_dest, ch);
458 GNUNET_break (NULL == ch->dest_rel);
459 ch->dest_rel = GNUNET_new (struct CadetChannelReliability);
460 ch->dest_rel->ch = ch;
461 ch->dest_rel->expected_delay.rel_value_us = 0;
462 ch->dest_rel->retry_timer = CADET_RETRANSMIT_TIME;
469 * Set options in a channel, extracted from a bit flag field.
471 * @param ch Channel to set options to.
472 * @param options Bit array in host byte order.
475 channel_set_options (struct CadetChannel *ch, uint32_t options)
477 ch->nobuffer = (options & GNUNET_CADET_OPTION_NOBUFFER) != 0 ?
478 GNUNET_YES : GNUNET_NO;
479 ch->reliable = (options & GNUNET_CADET_OPTION_RELIABLE) != 0 ?
480 GNUNET_YES : GNUNET_NO;
485 * Get a bit flag field with the options of a channel.
487 * @param ch Channel to get options from.
489 * @return Bit array in host byte order.
492 channel_get_options (struct CadetChannel *ch)
498 options |= GNUNET_CADET_OPTION_NOBUFFER;
500 options |= GNUNET_CADET_OPTION_RELIABLE;
507 * Notify a client that the channel is no longer valid.
509 * @param ch Channel that is destroyed.
510 * @param local_only Should we avoid sending it to other peers?
513 send_destroy (struct CadetChannel *ch, int local_only)
515 struct GNUNET_CADET_ChannelManage msg;
517 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CHANNEL_DESTROY);
518 msg.header.size = htons (sizeof (msg));
519 msg.chid = htonl (ch->gid);
521 /* If root is not NULL, notify.
522 * If it's NULL, check lid_root. When a local destroy comes in, root
523 * is set to NULL but lid_root is left untouched. In this case, do nothing,
524 * the client is the one who requested the channel to be destroyed.
526 if (NULL != ch->root)
527 GML_send_channel_destroy (ch->root, ch->lid_root);
528 else if (0 == ch->lid_root && GNUNET_NO == local_only)
529 GCCH_send_prebuilt_message (&msg.header, ch, GNUNET_NO, NULL);
531 if (NULL != ch->dest)
532 GML_send_channel_destroy (ch->dest, ch->lid_dest);
533 else if (0 == ch->lid_dest && GNUNET_NO == local_only)
534 GCCH_send_prebuilt_message (&msg.header, ch, GNUNET_YES, NULL);
539 * Notify the destination client that a new incoming channel was created.
541 * @param ch Channel that was created.
544 send_client_create (struct CadetChannel *ch)
548 if (NULL == ch->dest)
552 opt |= GNUNET_YES == ch->reliable ? GNUNET_CADET_OPTION_RELIABLE : 0;
553 opt |= GNUNET_YES == ch->nobuffer ? GNUNET_CADET_OPTION_NOBUFFER : 0;
554 GML_send_channel_create (ch->dest, ch->lid_dest, ch->port, opt,
555 GCT_get_destination (ch->t));
561 * Send data to a client.
563 * If the client is ready, send directly, otherwise buffer while listening
567 * @param msg Message.
568 * @param fwd Is this a fwd (root->dest) message?
571 send_client_data (struct CadetChannel *ch,
572 const struct GNUNET_CADET_Data *msg,
577 if (ch->dest_rel->client_ready)
579 GML_send_data (ch->dest, msg, ch->lid_dest);
580 ch->dest_rel->client_ready = GNUNET_NO;
581 ch->dest_rel->mid_recv++;
584 add_buffered_data (msg, ch->dest_rel);
588 if (ch->root_rel->client_ready)
590 GML_send_data (ch->root, msg, ch->lid_root);
591 ch->root_rel->client_ready = GNUNET_NO;
592 ch->root_rel->mid_recv++;
595 add_buffered_data (msg, ch->root_rel);
601 * Send a buffered message to the client, for in order delivery or
602 * as result of client ACK.
604 * @param ch Channel on which to empty the message buffer.
605 * @param c Client to send to.
606 * @param fwd Is this to send FWD data?.
609 send_client_buffered_data (struct CadetChannel *ch,
610 struct CadetClient *c,
613 struct CadetReliableMessage *copy;
614 struct CadetChannelReliability *rel;
616 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_buffered_data\n");
617 rel = fwd ? ch->dest_rel : ch->root_rel;
618 if (GNUNET_NO == rel->client_ready)
620 LOG (GNUNET_ERROR_TYPE_DEBUG, "client not ready\n");
624 copy = rel->head_recv;
625 /* We never buffer channel management messages */
628 if (copy->mid == rel->mid_recv || GNUNET_NO == ch->reliable)
630 struct GNUNET_CADET_Data *msg = (struct GNUNET_CADET_Data *) ©[1];
632 LOG (GNUNET_ERROR_TYPE_DEBUG, " have %u! now expecting %u\n",
633 copy->mid, rel->mid_recv + 1);
634 send_client_data (ch, msg, fwd);
636 GNUNET_CONTAINER_DLL_remove (rel->head_recv, rel->tail_recv, copy);
637 LOG (GNUNET_ERROR_TYPE_DEBUG, " free copy recv MID %u (%p), %u left\n",
638 copy->mid, copy, rel->n_recv);
640 GCCH_send_data_ack (ch, fwd);
644 LOG (GNUNET_ERROR_TYPE_DEBUG, " reliable && don't have %u, next is %u\n",
645 rel->mid_recv, copy->mid);
646 if (GNUNET_YES == ch->destroy)
648 /* We don't have the next data piece and the remote peer has closed the
649 * channel. We won't receive it anymore, so just destroy the channel.
650 * FIXME: wait some time to allow other connections to
651 * deliver missing messages
653 send_destroy (ch, GNUNET_YES);
658 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_buffered_data END\n");
663 * Allow a client to send more data.
665 * In case the client was already allowed to send data, do nothing.
668 * @param fwd Is this a FWD ACK? (FWD ACKs are sent to root)
671 send_client_ack (struct CadetChannel *ch, int fwd)
673 struct CadetChannelReliability *rel = fwd ? ch->root_rel : ch->dest_rel;
674 struct CadetClient *c = fwd ? ch->root : ch->dest;
678 GNUNET_break (GNUNET_NO != ch->destroy);
681 LOG (GNUNET_ERROR_TYPE_DEBUG,
682 " sending %s ack to client on channel %s\n",
683 GC_f2s (fwd), GCCH_2s (ch));
691 if (GNUNET_YES == rel->client_allowed)
693 LOG (GNUNET_ERROR_TYPE_DEBUG, " already allowed\n");
696 rel->client_allowed = GNUNET_YES;
698 GML_send_ack (c, fwd ? ch->lid_root : ch->lid_dest);
703 * Notify the root that the destination rejected the channel.
705 * @param ch Rejected channel.
708 send_client_nack (struct CadetChannel *ch)
710 if (NULL == ch->root)
715 GML_send_channel_nack (ch->root, ch->lid_root);
720 * We haven't received an ACK after a certain time: restransmit the message.
722 * @param cls Closure (CadetChannelReliability with the message to restransmit)
723 * @param tc TaskContext.
726 channel_retransmit_message (void *cls,
727 const struct GNUNET_SCHEDULER_TaskContext *tc)
729 struct CadetChannelReliability *rel = cls;
730 struct CadetReliableMessage *copy;
731 struct CadetChannel *ch;
732 struct GNUNET_CADET_Data *payload;
735 rel->retry_task = NULL;
736 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
740 copy = rel->head_sent;
743 GNUNET_break (0); // FIXME tripped in rps testcase
747 payload = (struct GNUNET_CADET_Data *) ©[1];
748 fwd = (rel == ch->root_rel);
750 /* Message not found in the queue that we are going to use. */
751 LOG (GNUNET_ERROR_TYPE_DEBUG, "RETRANSMIT MID %u\n", copy->mid);
753 GCCH_send_prebuilt_message (&payload->header, ch, fwd, copy);
754 GNUNET_STATISTICS_update (stats, "# data retransmitted", 1, GNUNET_NO);
759 * We haven't received an Channel ACK after a certain time: resend the CREATE.
761 * @param cls Closure (CadetChannelReliability of the channel to recreate)
762 * @param tc TaskContext.
765 channel_recreate (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
767 struct CadetChannelReliability *rel = cls;
769 rel->retry_task = NULL;
770 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
773 LOG (GNUNET_ERROR_TYPE_DEBUG, "RE-CREATE\n");
774 GNUNET_STATISTICS_update (stats, "# data retransmitted", 1, GNUNET_NO);
776 if (rel == rel->ch->root_rel)
778 send_create (rel->ch);
780 else if (rel == rel->ch->dest_rel)
782 send_ack (rel->ch, GNUNET_YES);
793 * Message has been sent: start retransmission timer.
795 * @param cls Closure (queue structure).
797 * @param q Queue handler (no longer valid).
798 * @param type Type of message.
799 * @param size Size of the message.
802 ch_message_sent (void *cls,
803 struct CadetTunnel *t,
804 struct CadetTunnelQueue *q,
805 uint16_t type, size_t size)
807 struct CadetChannelQueue *chq = cls;
808 struct CadetReliableMessage *copy = chq->copy;
809 struct CadetChannelReliability *rel;
811 LOG (GNUNET_ERROR_TYPE_DEBUG, "channel_message_sent callback %s\n",
816 case GNUNET_MESSAGE_TYPE_CADET_DATA:
817 LOG (GNUNET_ERROR_TYPE_DEBUG, "data MID %u sent\n", copy->mid);
818 GNUNET_assert (chq == copy->chq);
819 copy->timestamp = GNUNET_TIME_absolute_get ();
821 if (NULL == rel->retry_task)
823 LOG (GNUNET_ERROR_TYPE_DEBUG, " scheduling retry in %d * %s\n",
824 CADET_RETRANSMIT_MARGIN,
825 GNUNET_STRINGS_relative_time_to_string (rel->expected_delay,
827 if (0 != rel->expected_delay.rel_value_us)
830 GNUNET_TIME_relative_multiply (rel->expected_delay,
831 CADET_RETRANSMIT_MARGIN);
835 rel->retry_timer = CADET_RETRANSMIT_TIME;
837 LOG (GNUNET_ERROR_TYPE_DEBUG, " using delay %s\n",
838 GNUNET_STRINGS_relative_time_to_string (rel->retry_timer,
841 GNUNET_SCHEDULER_add_delayed (rel->retry_timer,
842 &channel_retransmit_message, rel);
846 LOG (GNUNET_ERROR_TYPE_DEBUG, "retry running %p\n", rel->retry_task);
852 case GNUNET_MESSAGE_TYPE_CADET_DATA_ACK:
853 case GNUNET_MESSAGE_TYPE_CADET_CHANNEL_CREATE:
854 case GNUNET_MESSAGE_TYPE_CADET_CHANNEL_ACK:
855 LOG (GNUNET_ERROR_TYPE_DEBUG, "sent %s\n", GC_m2s (chq->type));
857 GNUNET_assert (rel->uniq == chq);
860 if (CADET_CHANNEL_READY != rel->ch->state
861 && GNUNET_MESSAGE_TYPE_CADET_DATA_ACK != type
862 && GNUNET_NO == rel->ch->destroy)
864 GNUNET_assert (NULL == rel->retry_task);
865 LOG (GNUNET_ERROR_TYPE_DEBUG, "STD BACKOFF %s\n",
866 GNUNET_STRINGS_relative_time_to_string (rel->retry_timer,
868 rel->retry_timer = GNUNET_TIME_STD_BACKOFF (rel->retry_timer);
869 rel->retry_task = GNUNET_SCHEDULER_add_delayed (rel->retry_timer,
870 &channel_recreate, rel);
883 * send a channel create message.
885 * @param ch Channel for which to send.
888 send_create (struct CadetChannel *ch)
890 struct GNUNET_CADET_ChannelCreate msgcc;
892 msgcc.header.size = htons (sizeof (msgcc));
893 msgcc.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CHANNEL_CREATE);
894 msgcc.chid = htonl (ch->gid);
895 msgcc.port = htonl (ch->port);
896 msgcc.opt = htonl (channel_get_options (ch));
898 GCCH_send_prebuilt_message (&msgcc.header, ch, GNUNET_YES, NULL);
903 * Confirm we got a channel create or FWD ack.
905 * @param ch The channel to confirm.
906 * @param fwd Should we send a FWD ACK? (going dest->root)
909 send_ack (struct CadetChannel *ch, int fwd)
911 struct GNUNET_CADET_ChannelManage msg;
913 msg.header.size = htons (sizeof (msg));
914 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CHANNEL_ACK);
915 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending channel %s ack for channel %s\n",
916 GC_f2s (fwd), GCCH_2s (ch));
918 msg.chid = htonl (ch->gid);
919 GCCH_send_prebuilt_message (&msg.header, ch, !fwd, NULL);
924 * Send a message and don't keep any info about it: we won't need to cancel it
927 * @param msg Header of the message to fire away.
928 * @param ch Channel on which the message should go.
929 * @param force Is this a forced (undroppable) message?
932 fire_and_forget (const struct GNUNET_MessageHeader *msg,
933 struct CadetChannel *ch,
936 GNUNET_break (NULL == GCT_send_prebuilt_message (msg, ch->t, NULL,
942 * Notify that a channel create didn't succeed.
944 * @param ch The channel to reject.
947 send_nack (struct CadetChannel *ch)
949 struct GNUNET_CADET_ChannelManage msg;
951 msg.header.size = htons (sizeof (msg));
952 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CHANNEL_NACK);
953 LOG (GNUNET_ERROR_TYPE_DEBUG,
954 " sending channel NACK for channel %s\n",
957 msg.chid = htonl (ch->gid);
958 GCCH_send_prebuilt_message (&msg.header, ch, GNUNET_NO, NULL);
963 * Destroy all reliable messages queued for a channel,
964 * during a channel destruction.
965 * Frees the reliability structure itself.
967 * @param rel Reliability data for a channel.
970 channel_rel_free_all (struct CadetChannelReliability *rel)
972 struct CadetReliableMessage *copy;
973 struct CadetReliableMessage *next;
978 for (copy = rel->head_recv; NULL != copy; copy = next)
981 GNUNET_CONTAINER_DLL_remove (rel->head_recv, rel->tail_recv, copy);
982 LOG (GNUNET_ERROR_TYPE_DEBUG, " COPYFREE ALL RECV %p\n", copy);
983 GNUNET_break (NULL == copy->chq);
986 for (copy = rel->head_sent; NULL != copy; copy = next)
989 GNUNET_CONTAINER_DLL_remove (rel->head_sent, rel->tail_sent, copy);
990 LOG (GNUNET_ERROR_TYPE_DEBUG, " COPYFREE ALL SEND %p\n", copy);
991 if (NULL != copy->chq)
993 if (NULL != copy->chq->tq)
995 GCT_cancel (copy->chq->tq);
996 /* ch_message_sent will free copy->q */
1000 GNUNET_free (copy->chq);
1006 if (NULL != rel->uniq && NULL != rel->uniq->tq)
1008 GCT_cancel (rel->uniq->tq);
1009 /* ch_message_sent is called freeing uniq */
1011 if (NULL != rel->retry_task)
1013 GNUNET_SCHEDULER_cancel (rel->retry_task);
1014 rel->retry_task = NULL;
1021 * Mark future messages as ACK'd.
1023 * @param rel Reliability data.
1024 * @param msg DataACK message with a bitfield of future ACK'd messages.
1026 * @return How many messages have been freed.
1029 channel_rel_free_sent (struct CadetChannelReliability *rel,
1030 const struct GNUNET_CADET_DataACK *msg)
1032 struct CadetReliableMessage *copy;
1033 struct CadetReliableMessage *next;
1041 bitfield = msg->futures;
1042 mid = ntohl (msg->mid);
1043 LOG (GNUNET_ERROR_TYPE_DEBUG, "free_sent_reliable %u %llX\n", mid, bitfield);
1044 LOG (GNUNET_ERROR_TYPE_DEBUG, " rel %p, head %p\n", rel, rel->head_sent);
1045 for (i = 0, r = 0, copy = rel->head_sent;
1046 i < 64 && NULL != copy && 0 != bitfield;
1049 LOG (GNUNET_ERROR_TYPE_DEBUG, " trying bit %u (mid %u)\n", i, mid + i + 1);
1051 if (0 == (bitfield & mask))
1054 LOG (GNUNET_ERROR_TYPE_DEBUG, " set!\n");
1055 /* Bit was set, clear the bit from the bitfield */
1058 /* The i-th bit was set. Do we have that copy? */
1059 /* Skip copies with mid < target */
1060 target = mid + i + 1;
1061 LOG (GNUNET_ERROR_TYPE_DEBUG, " target %u\n", target);
1062 while (NULL != copy && GC_is_pid_bigger (target, copy->mid))
1065 /* Did we run out of copies? (previously freed, it's ok) */
1068 LOG (GNUNET_ERROR_TYPE_DEBUG, "run out of copies...\n");
1072 /* Did we overshoot the target? (previously freed, it's ok) */
1073 if (GC_is_pid_bigger (copy->mid, target))
1075 LOG (GNUNET_ERROR_TYPE_DEBUG, " next copy %u\n", copy->mid);
1076 i += copy->mid - target - 1; /* MID: 90, t = 85, i += 4 (i++ later) */
1077 mask = (0x1LL << (i + 1)) - 1; /* Mask = i-th bit and all before */
1078 bitfield &= ~mask; /* Clear all bits up to MID - 1 */
1082 /* Now copy->mid == target, free it */
1084 GNUNET_break (GNUNET_YES != rel_message_free (copy, GNUNET_YES));
1088 LOG (GNUNET_ERROR_TYPE_DEBUG, "free_sent_reliable END\n");
1094 * Destroy a reliable message after it has been acknowledged, either by
1095 * direct mid ACK or bitfield. Updates the appropriate data structures and
1096 * timers and frees all memory.
1098 * @param copy Message that is no longer needed: remote peer got it.
1099 * @param update_time Is the timing information relevant?
1100 * If this message is ACK in a batch the timing information
1101 * is skewed by the retransmission, count only for the
1102 * retransmitted message.
1104 * @return #GNUNET_YES if channel was destroyed as a result of the call,
1105 * #GNUNET_NO otherwise.
1108 rel_message_free (struct CadetReliableMessage *copy, int update_time)
1110 struct CadetChannelReliability *rel;
1111 struct GNUNET_TIME_Relative time;
1114 LOG (GNUNET_ERROR_TYPE_DEBUG, "Freeing %u\n", copy->mid);
1115 if (GNUNET_YES == update_time)
1117 time = GNUNET_TIME_absolute_get_duration (copy->timestamp);
1118 if (0 == rel->expected_delay.rel_value_us)
1119 rel->expected_delay = time;
1122 rel->expected_delay.rel_value_us *= 7;
1123 rel->expected_delay.rel_value_us += time.rel_value_us;
1124 rel->expected_delay.rel_value_us /= 8;
1126 LOG (GNUNET_ERROR_TYPE_DEBUG, " message time %12s\n",
1127 GNUNET_STRINGS_relative_time_to_string (time, GNUNET_NO));
1128 LOG (GNUNET_ERROR_TYPE_DEBUG, " new delay %12s\n",
1129 GNUNET_STRINGS_relative_time_to_string (rel->expected_delay,
1131 rel->retry_timer = rel->expected_delay;
1135 LOG (GNUNET_ERROR_TYPE_DEBUG, "batch free, ignoring timing\n");
1137 rel->ch->pending_messages--;
1138 if (NULL != copy->chq)
1140 GCT_cancel (copy->chq->tq);
1141 /* copy->q is set to NULL by ch_message_sent */
1143 GNUNET_CONTAINER_DLL_remove (rel->head_sent, rel->tail_sent, copy);
1144 LOG (GNUNET_ERROR_TYPE_DEBUG, " free send copy MID %u at %p\n",
1148 if (GNUNET_NO != rel->ch->destroy && 0 == rel->ch->pending_messages)
1150 GCCH_destroy (rel->ch);
1158 * Channel was ACK'd by remote peer, mark as ready and cancel retransmission.
1160 * @param ch Channel to mark as ready.
1161 * @param fwd Was the ACK message a FWD ACK? (dest->root, SYNACK)
1164 channel_confirm (struct CadetChannel *ch, int fwd)
1166 struct CadetChannelReliability *rel;
1167 enum CadetChannelState oldstate;
1169 rel = fwd ? ch->root_rel : ch->dest_rel;
1172 GNUNET_break (GNUNET_NO != ch->destroy);
1175 LOG (GNUNET_ERROR_TYPE_DEBUG, " channel confirm %s %s\n",
1176 GC_f2s (fwd), GCCH_2s (ch));
1177 oldstate = ch->state;
1178 ch->state = CADET_CHANNEL_READY;
1180 if (CADET_CHANNEL_READY != oldstate || GNUNET_YES == is_loopback (ch))
1182 rel->client_ready = GNUNET_YES;
1183 rel->expected_delay = rel->retry_timer;
1184 LOG (GNUNET_ERROR_TYPE_DEBUG, " confirm retry timer %s\n",
1185 GNUNET_STRINGS_relative_time_to_string (rel->retry_timer, GNUNET_NO));
1186 if (GCT_get_connections_buffer (ch->t) > 0 || GCT_is_loopback (ch->t))
1187 send_client_ack (ch, fwd);
1189 if (NULL != rel->retry_task)
1191 GNUNET_SCHEDULER_cancel (rel->retry_task);
1192 rel->retry_task = NULL;
1194 else if (NULL != rel->uniq)
1196 GCT_cancel (rel->uniq->tq);
1197 /* ch_message_sent will free and NULL uniq */
1199 else if (GNUNET_NO == is_loopback (ch))
1201 /* We SHOULD have been trying to retransmit this! */
1206 /* In case of a FWD ACK (SYNACK) send a BCK ACK (ACK). */
1207 if (GNUNET_YES == fwd)
1208 send_ack (ch, GNUNET_NO);
1213 * Save a copy to retransmit in case it gets lost.
1215 * Initializes all needed callbacks and timers.
1217 * @param ch Channel this message goes on.
1218 * @param msg Message to copy.
1219 * @param fwd Is this fwd traffic?
1221 static struct CadetReliableMessage *
1222 channel_save_copy (struct CadetChannel *ch,
1223 const struct GNUNET_MessageHeader *msg,
1226 struct CadetChannelReliability *rel;
1227 struct CadetReliableMessage *copy;
1232 rel = fwd ? ch->root_rel : ch->dest_rel;
1233 mid = rel->mid_send - 1;
1234 type = ntohs (msg->type);
1235 size = ntohs (msg->size);
1237 LOG (GNUNET_ERROR_TYPE_DEBUG, "save MID %u %s\n", mid, GC_m2s (type));
1238 copy = GNUNET_malloc (sizeof (struct CadetReliableMessage) + size);
1239 LOG (GNUNET_ERROR_TYPE_DEBUG, " at %p\n", copy);
1243 memcpy (©[1], msg, size);
1244 GNUNET_CONTAINER_DLL_insert_tail (rel->head_sent, rel->tail_sent, copy);
1245 ch->pending_messages++;
1252 * Create a new channel.
1254 * @param t Tunnel this channel is in.
1255 * @param owner Client that owns the channel, NULL for foreign channels.
1256 * @param lid_root Local ID for root client.
1258 * @return A new initialized channel. NULL on error.
1260 static struct CadetChannel *
1261 channel_new (struct CadetTunnel *t,
1262 struct CadetClient *owner,
1263 CADET_ChannelNumber lid_root)
1265 struct CadetChannel *ch;
1267 ch = GNUNET_new (struct CadetChannel);
1269 ch->lid_root = lid_root;
1272 GNUNET_STATISTICS_update (stats, "# channels", 1, GNUNET_NO);
1276 ch->gid = GCT_get_next_chid (t);
1277 GML_channel_add (owner, lid_root, ch);
1279 GCT_add_channel (t, ch);
1286 * Handle a loopback message: call the appropriate handler for the message type.
1288 * @param ch Channel this message is on.
1289 * @param msgh Message header.
1290 * @param fwd Is this FWD traffic?
1293 handle_loopback (struct CadetChannel *ch,
1294 const struct GNUNET_MessageHeader *msgh,
1299 type = ntohs (msgh->type);
1300 LOG (GNUNET_ERROR_TYPE_DEBUG,
1301 "Loopback %s %s message!\n",
1302 GC_f2s (fwd), GC_m2s (type));
1306 case GNUNET_MESSAGE_TYPE_CADET_DATA:
1307 /* Don't send hop ACK, wait for client to ACK */
1308 LOG (GNUNET_ERROR_TYPE_DEBUG, "SEND loopback %u (%u)\n",
1309 ntohl (((struct GNUNET_CADET_Data *) msgh)->mid), ntohs (msgh->size));
1310 GCCH_handle_data (ch, (struct GNUNET_CADET_Data *) msgh, fwd);
1313 case GNUNET_MESSAGE_TYPE_CADET_DATA_ACK:
1314 GCCH_handle_data_ack (ch, (struct GNUNET_CADET_DataACK *) msgh, fwd);
1317 case GNUNET_MESSAGE_TYPE_CADET_CHANNEL_CREATE:
1318 GCCH_handle_create (ch->t,
1319 (struct GNUNET_CADET_ChannelCreate *) msgh);
1322 case GNUNET_MESSAGE_TYPE_CADET_CHANNEL_ACK:
1323 GCCH_handle_ack (ch,
1324 (struct GNUNET_CADET_ChannelManage *) msgh,
1328 case GNUNET_MESSAGE_TYPE_CADET_CHANNEL_NACK:
1329 GCCH_handle_nack (ch);
1332 case GNUNET_MESSAGE_TYPE_CADET_CHANNEL_DESTROY:
1333 GCCH_handle_destroy (ch,
1334 (struct GNUNET_CADET_ChannelManage *) msgh,
1339 GNUNET_break_op (0);
1340 LOG (GNUNET_ERROR_TYPE_DEBUG,
1341 "end-to-end message not known (%u)\n",
1342 ntohs (msgh->type));
1348 /******************************************************************************/
1349 /******************************** API ***********************************/
1350 /******************************************************************************/
1353 * Destroy a channel and free all resources.
1355 * @param ch Channel to destroy.
1358 GCCH_destroy (struct CadetChannel *ch)
1360 struct CadetClient *c;
1361 struct CadetTunnel *t;
1365 if (2 == ch->destroy)
1366 return; /* recursive call */
1369 LOG (GNUNET_ERROR_TYPE_DEBUG, "destroying channel %s:%u\n",
1370 GCT_2s (ch->t), ch->gid);
1376 GML_channel_remove (c, ch->lid_root, ch);
1382 GML_channel_remove (c, ch->lid_dest, ch);
1385 channel_rel_free_all (ch->root_rel);
1386 channel_rel_free_all (ch->dest_rel);
1389 GCT_remove_channel (t, ch);
1390 GNUNET_STATISTICS_update (stats, "# channels", -1, GNUNET_NO);
1393 GCT_destroy_if_empty (t);
1398 * Get the channel's public ID.
1400 * @param ch Channel.
1402 * @return ID used to identify the channel with the remote peer.
1405 GCCH_get_id (const struct CadetChannel *ch)
1412 * Get the channel tunnel.
1414 * @param ch Channel to get the tunnel from.
1416 * @return tunnel of the channel.
1418 struct CadetTunnel *
1419 GCCH_get_tunnel (const struct CadetChannel *ch)
1426 * Get free buffer space towards the client on a specific channel.
1428 * @param ch Channel.
1429 * @param fwd Is query about FWD traffic?
1431 * @return Free buffer space [0 - 64]
1434 GCCH_get_buffer (struct CadetChannel *ch, int fwd)
1436 struct CadetChannelReliability *rel;
1438 rel = fwd ? ch->dest_rel : ch->root_rel;
1439 LOG (GNUNET_ERROR_TYPE_DEBUG, " get buffer, channel %s\n", GCCH_2s (ch));
1441 /* If rel is NULL it means that the end is not yet created,
1442 * most probably is a loopback channel at the point of sending
1443 * the ChannelCreate to itself.
1447 LOG (GNUNET_ERROR_TYPE_DEBUG, " rel is NULL: max\n");
1451 LOG (GNUNET_ERROR_TYPE_DEBUG, " n_recv %d\n", rel->n_recv);
1452 return (64 - rel->n_recv);
1457 * Get flow control status of end point: is client allow to send?
1459 * @param ch Channel.
1460 * @param fwd Is query about FWD traffic? (Request root status).
1462 * @return #GNUNET_YES if client is allowed to send us data.
1465 GCCH_get_allowed (struct CadetChannel *ch, int fwd)
1467 struct CadetChannelReliability *rel;
1469 rel = fwd ? ch->root_rel : ch->dest_rel;
1473 /* Probably shutting down: root/dest NULL'ed to mark disconnection */
1474 GNUNET_break (GNUNET_NO != ch->destroy);
1478 return rel->client_allowed;
1483 * Is the root client for this channel on this peer?
1485 * @param ch Channel.
1486 * @param fwd Is this for fwd traffic?
1488 * @return #GNUNET_YES in case it is.
1491 GCCH_is_origin (struct CadetChannel *ch, int fwd)
1493 struct CadetClient *c;
1495 c = fwd ? ch->root : ch->dest;
1501 * Is the destination client for this channel on this peer?
1503 * @param ch Channel.
1504 * @param fwd Is this for fwd traffic?
1506 * @return #GNUNET_YES in case it is.
1509 GCCH_is_terminal (struct CadetChannel *ch, int fwd)
1511 struct CadetClient *c;
1513 c = fwd ? ch->dest : ch->root;
1519 * Send an end-to-end ACK message for the most recent in-sequence payload.
1521 * If channel is not reliable, do nothing.
1523 * @param ch Channel this is about.
1524 * @param fwd Is for FWD traffic? (ACK dest->owner)
1527 GCCH_send_data_ack (struct CadetChannel *ch, int fwd)
1529 struct GNUNET_CADET_DataACK msg;
1530 struct CadetChannelReliability *rel;
1531 struct CadetReliableMessage *copy;
1536 if (GNUNET_NO == ch->reliable)
1539 rel = fwd ? ch->dest_rel : ch->root_rel;
1540 ack = rel->mid_recv - 1;
1542 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_DATA_ACK);
1543 msg.header.size = htons (sizeof (msg));
1544 msg.chid = htonl (ch->gid);
1545 msg.mid = htonl (ack);
1548 for (copy = rel->head_recv; NULL != copy; copy = copy->next)
1550 if (copy->type != GNUNET_MESSAGE_TYPE_CADET_DATA)
1552 LOG (GNUNET_ERROR_TYPE_DEBUG, " Type %s, expected DATA\n",
1553 GC_m2s (copy->type));
1556 GNUNET_assert (GC_is_pid_bigger(copy->mid, ack));
1557 delta = copy->mid - (ack + 1);
1560 mask = 0x1LL << delta;
1561 msg.futures |= mask;
1562 LOG (GNUNET_ERROR_TYPE_DEBUG,
1563 " setting bit for %u (delta %u) (%llX) -> %llX\n",
1564 copy->mid, delta, mask, msg.futures);
1566 LOG (GNUNET_ERROR_TYPE_INFO, "===> DATA_ACK for %u + %llX\n",
1569 GCCH_send_prebuilt_message (&msg.header, ch, !fwd, NULL);
1570 LOG (GNUNET_ERROR_TYPE_DEBUG, "send_data_ack END\n");
1575 * Allow a client to send us more data, in case it was choked.
1577 * @param ch Channel.
1578 * @param fwd Is this about FWD traffic? (Root client).
1581 GCCH_allow_client (struct CadetChannel *ch, int fwd)
1583 struct CadetChannelReliability *rel;
1584 unsigned int buffer;
1586 LOG (GNUNET_ERROR_TYPE_DEBUG, "GMCH allow\n");
1588 if (CADET_CHANNEL_READY != ch->state)
1590 LOG (GNUNET_ERROR_TYPE_DEBUG, " channel not ready yet!\n");
1594 if (GNUNET_YES == ch->reliable)
1596 rel = fwd ? ch->root_rel : ch->dest_rel;
1599 GNUNET_break (GNUNET_NO != ch->destroy);
1602 if (NULL != rel->head_sent)
1604 if (64 <= rel->mid_send - rel->head_sent->mid)
1606 LOG (GNUNET_ERROR_TYPE_DEBUG, " too big MID gap! Wait for ACK.\n");
1611 LOG (GNUNET_ERROR_TYPE_DEBUG, " gap ok: %u - %u\n",
1612 rel->head_sent->mid, rel->mid_send);
1613 struct CadetReliableMessage *aux;
1614 for (aux = rel->head_sent; NULL != aux; aux = aux->next)
1616 LOG (GNUNET_ERROR_TYPE_DEBUG, " - sent mid %u\n", aux->mid);
1622 LOG (GNUNET_ERROR_TYPE_DEBUG, " head sent is NULL\n");
1626 if (is_loopback (ch))
1627 buffer = GCCH_get_buffer (ch, fwd);
1629 buffer = GCT_get_connections_buffer (ch->t);
1633 LOG (GNUNET_ERROR_TYPE_DEBUG, " no buffer space.\n");
1637 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer space %u, allowing\n", buffer);
1638 send_client_ack (ch, fwd);
1645 * @param ch Channel.
1648 GCCH_debug (struct CadetChannel *ch)
1652 LOG (GNUNET_ERROR_TYPE_DEBUG, "*** DEBUG NULL CHANNEL ***\n");
1655 LOG (GNUNET_ERROR_TYPE_DEBUG, "Channel %s:%X (%p)\n",
1656 GCT_2s (ch->t), ch->gid, ch);
1657 LOG (GNUNET_ERROR_TYPE_DEBUG, " root %p/%p\n",
1658 ch->root, ch->root_rel);
1659 if (NULL != ch->root)
1661 LOG (GNUNET_ERROR_TYPE_DEBUG, " cli %s\n", GML_2s (ch->root));
1662 LOG (GNUNET_ERROR_TYPE_DEBUG, " ready %s\n",
1663 ch->root_rel->client_ready ? "YES" : "NO");
1664 LOG (GNUNET_ERROR_TYPE_DEBUG, " id %X\n", ch->lid_root);
1665 LOG (GNUNET_ERROR_TYPE_DEBUG, " recv %d\n", ch->root_rel->n_recv);
1666 LOG (GNUNET_ERROR_TYPE_DEBUG, " MID r: %d, s: %d\n",
1667 ch->root_rel->mid_recv, ch->root_rel->mid_send);
1669 LOG (GNUNET_ERROR_TYPE_DEBUG, " dest %p/%p\n",
1670 ch->dest, ch->dest_rel);
1671 if (NULL != ch->dest)
1673 LOG (GNUNET_ERROR_TYPE_DEBUG, " cli %s\n", GML_2s (ch->dest));
1674 LOG (GNUNET_ERROR_TYPE_DEBUG, " ready %s\n",
1675 ch->dest_rel->client_ready ? "YES" : "NO");
1676 LOG (GNUNET_ERROR_TYPE_DEBUG, " id %X\n", ch->lid_dest);
1677 LOG (GNUNET_ERROR_TYPE_DEBUG, " recv %d\n", ch->dest_rel->n_recv);
1678 LOG (GNUNET_ERROR_TYPE_DEBUG, " MID r: %d, s: %d\n",
1679 ch->dest_rel->mid_recv, ch->dest_rel->mid_send);
1686 * Handle an ACK given by a client.
1688 * Mark client as ready and send him any buffered data we could have for him.
1690 * @param ch Channel.
1691 * @param fwd Is this a "FWD ACK"? (FWD ACKs are sent by dest and go BCK)
1694 GCCH_handle_local_ack (struct CadetChannel *ch, int fwd)
1696 struct CadetChannelReliability *rel;
1697 struct CadetClient *c;
1699 rel = fwd ? ch->dest_rel : ch->root_rel;
1700 c = fwd ? ch->dest : ch->root;
1702 rel->client_ready = GNUNET_YES;
1703 send_client_buffered_data (ch, c, fwd);
1705 if (GNUNET_YES == ch->destroy && 0 == rel->n_recv)
1707 send_destroy (ch, GNUNET_YES);
1711 /* if loopback is marked for destruction, no need to ACK to the other peer,
1712 * it requested the destruction and is already gone, therefore, else if.
1714 else if (is_loopback (ch))
1716 unsigned int buffer;
1718 buffer = GCCH_get_buffer (ch, fwd);
1720 GCCH_allow_client (ch, fwd);
1724 GCT_send_connection_acks (ch->t);
1729 * Handle data given by a client.
1731 * Check whether the client is allowed to send in this tunnel, save if channel
1732 * is reliable and send an ACK to the client if there is still buffer space
1735 * @param ch Channel.
1736 * @param c Client which sent the data.
1737 * @param fwd Is this a FWD data?
1738 * @param message Data message.
1739 * @param size Size of data.
1741 * @return GNUNET_OK if everything goes well, GNUNET_SYSERR in case of en error.
1744 GCCH_handle_local_data (struct CadetChannel *ch,
1745 struct CadetClient *c, int fwd,
1746 const struct GNUNET_MessageHeader *message,
1749 struct CadetChannelReliability *rel;
1750 struct GNUNET_CADET_Data *payload;
1751 uint16_t p2p_size = sizeof(struct GNUNET_CADET_Data) + size;
1752 unsigned char cbuf[p2p_size];
1753 unsigned char buffer;
1755 /* Is the client in the channel? */
1762 GNUNET_break_op (0);
1763 return GNUNET_SYSERR;
1766 rel = fwd ? ch->root_rel : ch->dest_rel;
1768 if (GNUNET_NO == rel->client_allowed)
1770 GNUNET_break_op (0);
1771 return GNUNET_SYSERR;
1774 rel->client_allowed = GNUNET_NO;
1776 /* Ok, everything is correct, send the message. */
1777 payload = (struct GNUNET_CADET_Data *) cbuf;
1778 payload->mid = htonl (rel->mid_send);
1780 memcpy (&payload[1], message, size);
1781 payload->header.size = htons (p2p_size);
1782 payload->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_DATA);
1783 payload->chid = htonl (ch->gid);
1784 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channel...\n");
1785 GCCH_send_prebuilt_message (&payload->header, ch, fwd, NULL);
1787 if (is_loopback (ch))
1788 buffer = GCCH_get_buffer (ch, fwd);
1790 buffer = GCT_get_connections_buffer (ch->t);
1793 GCCH_allow_client (ch, fwd);
1800 * Handle a channel destroy requested by a client.
1802 * TODO: add "reason" field
1804 * Destroy the channel and the tunnel in case this was the last channel.
1806 * @param ch Channel.
1807 * @param c Client that requested the destruction (to avoid notifying him).
1808 * @param is_root Is the request coming from root?
1811 GCCH_handle_local_destroy (struct CadetChannel *ch,
1812 struct CadetClient *c,
1815 ch->destroy = GNUNET_YES;
1816 /* Cleanup after the tunnel */
1817 if (GNUNET_NO == is_root && c == ch->dest)
1819 LOG (GNUNET_ERROR_TYPE_DEBUG, " Client %s is destination.\n", GML_2s (c));
1820 GML_client_delete_channel (c, ch, ch->lid_dest);
1823 if (GNUNET_YES == is_root && c == ch->root)
1825 LOG (GNUNET_ERROR_TYPE_DEBUG, " Client %s is owner.\n", GML_2s (c));
1826 GML_client_delete_channel (c, ch, ch->lid_root);
1830 send_destroy (ch, GNUNET_NO);
1831 if (0 == ch->pending_messages)
1837 * Handle a channel create requested by a client.
1839 * Create the channel and the tunnel in case this was the first0 channel.
1841 * @param c Client that requested the creation (will be the root).
1842 * @param msg Create Channel message.
1844 * @return GNUNET_OK if everything went fine, GNUNET_SYSERR otherwise.
1847 GCCH_handle_local_create (struct CadetClient *c,
1848 struct GNUNET_CADET_ChannelMessage *msg)
1850 struct CadetChannel *ch;
1851 struct CadetTunnel *t;
1852 struct CadetPeer *peer;
1853 CADET_ChannelNumber chid;
1855 LOG (GNUNET_ERROR_TYPE_DEBUG, " towards %s:%u\n",
1856 GNUNET_i2s (&msg->peer), ntohl (msg->port));
1857 chid = ntohl (msg->channel_id);
1859 /* Sanity check for duplicate channel IDs */
1860 if (NULL != GML_channel_get (c, chid))
1863 return GNUNET_SYSERR;
1866 peer = GCP_get (&msg->peer, GNUNET_YES);
1867 GCP_add_tunnel (peer);
1868 t = GCP_get_tunnel (peer);
1870 if (GCP_get_short_id (peer) == myid)
1872 GCT_change_cstate (t, CADET_TUNNEL_READY);
1876 /* FIXME change to a tunnel API, eliminate ch <-> peer connection */
1880 /* Create channel */
1881 ch = channel_new (t, c, chid);
1885 return GNUNET_SYSERR;
1887 ch->port = ntohl (msg->port);
1888 channel_set_options (ch, ntohl (msg->opt));
1890 /* In unreliable channels, we'll use the DLL to buffer BCK data */
1891 ch->root_rel = GNUNET_new (struct CadetChannelReliability);
1892 ch->root_rel->ch = ch;
1893 ch->root_rel->retry_timer = CADET_RETRANSMIT_TIME;
1894 ch->root_rel->expected_delay.rel_value_us = 0;
1896 LOG (GNUNET_ERROR_TYPE_DEBUG, "CREATED CHANNEL %s\n", GCCH_2s (ch));
1905 * Handler for cadet network payload traffic.
1907 * @param ch Channel for the message.
1908 * @param msg Unencryted data message.
1909 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
1910 * #GNUNET_YES if message is FWD on the respective channel (loopback)
1911 * #GNUNET_NO if message is BCK on the respective channel (loopback)
1912 * #GNUNET_SYSERR if message on a one-ended channel (remote)
1915 GCCH_handle_data (struct CadetChannel *ch,
1916 const struct GNUNET_CADET_Data *msg,
1919 struct CadetChannelReliability *rel;
1920 struct CadetClient *c;
1923 /* If this is a remote (non-loopback) channel, find 'fwd'. */
1924 if (GNUNET_SYSERR == fwd)
1926 if (is_loopback (ch))
1928 /* It is a loopback channel after all... */
1932 fwd = (NULL != ch->dest) ? GNUNET_YES : GNUNET_NO;
1935 /* Initialize FWD/BCK data */
1936 c = fwd ? ch->dest : ch->root;
1937 rel = fwd ? ch->dest_rel : ch->root_rel;
1941 GNUNET_break (GNUNET_NO != ch->destroy);
1945 if (CADET_CHANNEL_READY != ch->state)
1947 if (GNUNET_NO == fwd)
1949 /* If we are the root, this means the other peer has sent traffic before
1950 * receiving our ACK. Even if the SYNACK goes missing, no traffic should
1951 * be sent before the ACK.
1953 GNUNET_break_op (0);
1956 /* If we are the dest, this means that the SYNACK got to the root but
1957 * the ACK went missing. Treat this as an ACK.
1959 channel_confirm (ch, GNUNET_NO);
1962 GNUNET_STATISTICS_update (stats, "# data received", 1, GNUNET_NO);
1964 mid = ntohl (msg->mid);
1965 LOG (GNUNET_ERROR_TYPE_INFO, "<=== DATA %u %s on channel %s\n",
1966 mid, GC_f2s (fwd), GCCH_2s (ch));
1968 if (GNUNET_NO == ch->reliable ||
1969 ( !GC_is_pid_bigger (rel->mid_recv, mid) &&
1970 GC_is_pid_bigger (rel->mid_recv + 64, mid) ) )
1972 LOG (GNUNET_ERROR_TYPE_DEBUG, "RECV MID %u (%u)\n",
1973 mid, ntohs (msg->header.size));
1974 if (GNUNET_YES == ch->reliable)
1976 /* Is this the exact next expected messasge? */
1977 if (mid == rel->mid_recv)
1979 LOG (GNUNET_ERROR_TYPE_DEBUG, "as expected, sending to client\n");
1980 send_client_data (ch, msg, fwd);
1984 LOG (GNUNET_ERROR_TYPE_DEBUG, "save for later\n");
1985 add_buffered_data (msg, rel);
1990 /* Tunnel is unreliable: send to clients directly */
1991 /* FIXME: accept Out Of Order traffic */
1992 rel->mid_recv = mid + 1;
1993 send_client_data (ch, msg, fwd);
1998 if (GC_is_pid_bigger (rel->mid_recv, mid))
2000 GNUNET_break_op (0);
2001 LOG (GNUNET_ERROR_TYPE_WARNING,
2002 "MID %u on channel %s not expected (window: %u - %u). Dropping!\n",
2003 mid, GCCH_2s (ch), rel->mid_recv, rel->mid_recv + 63);
2007 LOG (GNUNET_ERROR_TYPE_WARNING,
2008 "Duplicate MID %u, channel %s (expecting MID %u). Re-sending ACK!\n",
2009 mid, GCCH_2s (ch), rel->mid_recv);
2010 if (NULL != rel->uniq)
2012 LOG (GNUNET_ERROR_TYPE_WARNING,
2013 "We are trying to send an ACK, but don't seem have the "
2014 "bandwidth. Try to increase your ats QUOTA in you config file\n");
2020 GCCH_send_data_ack (ch, fwd);
2025 * Handler for cadet network traffic end-to-end ACKs.
2027 * @param ch Channel on which we got this message.
2028 * @param msg Data message.
2029 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
2030 * #GNUNET_YES if message is FWD on the respective channel (loopback)
2031 * #GNUNET_NO if message is BCK on the respective channel (loopback)
2032 * #GNUNET_SYSERR if message on a one-ended channel (remote)
2035 GCCH_handle_data_ack (struct CadetChannel *ch,
2036 const struct GNUNET_CADET_DataACK *msg,
2039 struct CadetChannelReliability *rel;
2040 struct CadetReliableMessage *copy;
2041 struct CadetReliableMessage *next;
2045 /* If this is a remote (non-loopback) channel, find 'fwd'. */
2046 if (GNUNET_SYSERR == fwd)
2048 if (is_loopback (ch))
2050 /* It is a loopback channel after all... */
2054 /* Inverted: if message came 'FWD' is a 'BCK ACK'. */
2055 fwd = (NULL != ch->dest) ? GNUNET_NO : GNUNET_YES;
2058 ack = ntohl (msg->mid);
2059 LOG (GNUNET_ERROR_TYPE_INFO, "<=== %s ACK %u + %llX\n",
2060 GC_f2s (fwd), ack, msg->futures);
2062 if (GNUNET_YES == fwd)
2069 GNUNET_break (GNUNET_NO != ch->destroy);
2073 /* Free ACK'd copies: no need to retransmit those anymore FIXME refactor */
2074 for (work = GNUNET_NO, copy = rel->head_sent; copy != NULL; copy = next)
2076 if (GC_is_pid_bigger (copy->mid, ack))
2078 LOG (GNUNET_ERROR_TYPE_DEBUG, " head %u, out!\n", copy->mid);
2079 if (0 < channel_rel_free_sent (rel, msg))
2084 LOG (GNUNET_ERROR_TYPE_DEBUG, " id %u\n", copy->mid);
2086 if (GNUNET_YES == rel_message_free (copy, GNUNET_YES))
2088 LOG (GNUNET_ERROR_TYPE_DEBUG, " channel destoyed\n");
2093 /* ACK client if needed and possible */
2094 GCCH_allow_client (ch, fwd);
2096 /* If some message was free'd, update the retransmission delay */
2097 if (GNUNET_YES == work)
2099 if (NULL != rel->retry_task)
2101 GNUNET_SCHEDULER_cancel (rel->retry_task);
2102 rel->retry_task = NULL;
2103 if (NULL != rel->head_sent && NULL == rel->head_sent->chq)
2105 struct GNUNET_TIME_Absolute new_target;
2106 struct GNUNET_TIME_Relative delay;
2108 delay = GNUNET_TIME_relative_multiply (rel->retry_timer,
2109 CADET_RETRANSMIT_MARGIN);
2110 new_target = GNUNET_TIME_absolute_add (rel->head_sent->timestamp,
2112 delay = GNUNET_TIME_absolute_get_remaining (new_target);
2114 GNUNET_SCHEDULER_add_delayed (delay,
2115 &channel_retransmit_message,
2121 /* Work was done but no task was pending? Shouldn't happen! */
2129 * Handler for channel create messages.
2131 * Does not have fwd parameter because it's always 'FWD': channel is incoming.
2133 * @param t Tunnel this channel will be in.
2134 * @param msg Channel crate message.
2136 struct CadetChannel *
2137 GCCH_handle_create (struct CadetTunnel *t,
2138 const struct GNUNET_CADET_ChannelCreate *msg)
2140 CADET_ChannelNumber chid;
2141 struct CadetChannel *ch;
2142 struct CadetClient *c;
2145 chid = ntohl (msg->chid);
2146 ch = GCT_get_channel (t, chid);
2149 /* Create channel */
2150 ch = channel_new (t, NULL, 0);
2152 channel_set_options (ch, ntohl (msg->opt));
2153 new_channel = GNUNET_YES;
2157 new_channel = GNUNET_NO;
2160 if (GNUNET_YES == new_channel || GCT_is_loopback (t))
2162 /* Find a destination client */
2163 ch->port = ntohl (msg->port);
2164 LOG (GNUNET_ERROR_TYPE_DEBUG, " port %u\n", ch->port);
2165 c = GML_client_get_by_port (ch->port);
2168 LOG (GNUNET_ERROR_TYPE_DEBUG, " no client has port registered\n");
2169 if (is_loopback (ch))
2171 LOG (GNUNET_ERROR_TYPE_DEBUG, " loopback: destroy on handler\n");
2176 LOG (GNUNET_ERROR_TYPE_DEBUG, " not loopback: destroy now\n");
2184 LOG (GNUNET_ERROR_TYPE_DEBUG, " client %p has port registered\n", c);
2187 add_destination (ch, c);
2188 if (GNUNET_YES == ch->reliable)
2189 LOG (GNUNET_ERROR_TYPE_DEBUG, "Reliable\n");
2191 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not Reliable\n");
2193 send_client_create (ch);
2194 ch->state = CADET_CHANNEL_SENT;
2198 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate create channel\n");
2199 if (NULL != ch->dest_rel->retry_task)
2201 LOG (GNUNET_ERROR_TYPE_DEBUG, " clearing retry task\n");
2202 /* we were waiting to re-send our 'SYNACK', wait no more! */
2203 GNUNET_SCHEDULER_cancel (ch->dest_rel->retry_task);
2204 ch->dest_rel->retry_task = NULL;
2206 else if (NULL != ch->dest_rel->uniq)
2208 /* we are waiting to for our 'SYNACK' to leave the queue, all done! */
2212 send_ack (ch, GNUNET_YES);
2219 * Handler for channel NACK messages.
2221 * NACK messages always go dest -> root, no need for 'fwd' or 'msg' parameter.
2223 * @param ch Channel.
2226 GCCH_handle_nack (struct CadetChannel *ch)
2228 send_client_nack (ch);
2234 * Handler for channel ack messages.
2236 * @param ch Channel.
2237 * @param msg Message.
2238 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
2239 * #GNUNET_YES if message is FWD on the respective channel (loopback)
2240 * #GNUNET_NO if message is BCK on the respective channel (loopback)
2241 * #GNUNET_SYSERR if message on a one-ended channel (remote)
2244 GCCH_handle_ack (struct CadetChannel *ch,
2245 const struct GNUNET_CADET_ChannelManage *msg,
2248 /* If this is a remote (non-loopback) channel, find 'fwd'. */
2249 if (GNUNET_SYSERR == fwd)
2251 if (is_loopback (ch))
2253 /* It is a loopback channel after all... */
2257 fwd = (NULL != ch->dest) ? GNUNET_YES : GNUNET_NO;
2260 channel_confirm (ch, !fwd);
2265 * Handler for channel destroy messages.
2267 * @param ch Channel to be destroyed of.
2268 * @param msg Message.
2269 * @param fwd Is this message fwd? This only is meaningful in loopback channels.
2270 * #GNUNET_YES if message is FWD on the respective channel (loopback)
2271 * #GNUNET_NO if message is BCK on the respective channel (loopback)
2272 * #GNUNET_SYSERR if message on a one-ended channel (remote)
2275 GCCH_handle_destroy (struct CadetChannel *ch,
2276 const struct GNUNET_CADET_ChannelManage *msg,
2279 struct CadetChannelReliability *rel;
2281 /* If this is a remote (non-loopback) channel, find 'fwd'. */
2282 if (GNUNET_SYSERR == fwd)
2284 if (is_loopback (ch))
2286 /* It is a loopback channel after all... */
2290 fwd = (NULL != ch->dest) ? GNUNET_YES : GNUNET_NO;
2294 if ( (fwd && NULL == ch->dest) || (!fwd && NULL == ch->root) )
2296 /* Not for us (don't destroy twice a half-open loopback channel) */
2300 rel = fwd ? ch->dest_rel : ch->root_rel;
2301 if (0 == rel->n_recv)
2303 send_destroy (ch, GNUNET_YES);
2308 ch->destroy = GNUNET_YES;
2314 * Sends an already built message on a channel.
2316 * If the channel is on a loopback tunnel, notifies the appropriate destination
2319 * On a normal channel passes the message to the tunnel for encryption and
2320 * sending on a connection.
2322 * This function DOES NOT save the message for retransmission.
2324 * @param message Message to send. Function makes a copy of it.
2325 * @param ch Channel on which this message is transmitted.
2326 * @param fwd Is this a fwd message?
2327 * @param existing_copy This is a retransmission, don't save a copy.
2330 GCCH_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
2331 struct CadetChannel *ch, int fwd,
2332 void *existing_copy)
2334 struct CadetChannelQueue *chq;
2337 type = ntohs (message->type);
2338 LOG (GNUNET_ERROR_TYPE_INFO, "===> %s %s on channel %s\n",
2339 GC_m2s (type), GC_f2s (fwd), GCCH_2s (ch));
2341 if (GCT_is_loopback (ch->t))
2343 handle_loopback (ch, message, fwd);
2349 struct GNUNET_CADET_Data *payload;
2350 case GNUNET_MESSAGE_TYPE_CADET_DATA:
2352 payload = (struct GNUNET_CADET_Data *) message;
2353 LOG (GNUNET_ERROR_TYPE_INFO, "===> %s %u\n",
2354 GC_m2s (type), ntohl (payload->mid));
2355 if (GNUNET_YES == ch->reliable)
2357 chq = GNUNET_new (struct CadetChannelQueue);
2359 if (NULL == existing_copy)
2360 chq->copy = channel_save_copy (ch, message, fwd);
2363 chq->copy = (struct CadetReliableMessage *) existing_copy;
2364 if (NULL != chq->copy->chq)
2366 /* Last retransmission was queued but not yet sent!
2367 * This retransmission was scheduled by a ch_message_sent which
2368 * followed a very fast RTT, so the tiny delay made the
2369 * retransmission function to execute before the previous
2370 * retransmitted message even had a chance to leave the peer.
2371 * Cancel this message and wait until the pending
2372 * retransmission leaves the peer and ch_message_sent starts
2373 * the timer for the next one.
2376 LOG (GNUNET_ERROR_TYPE_DEBUG,
2377 " exisitng copy not yet transmitted!\n");
2380 LOG (GNUNET_ERROR_TYPE_DEBUG,
2381 " using existing copy: %p {r:%p q:%p t:%u}\n",
2383 chq->copy->rel, chq->copy->chq, chq->copy->type);
2385 LOG (GNUNET_ERROR_TYPE_DEBUG, " new chq: %p\n", chq);
2386 chq->copy->chq = chq;
2387 chq->tq = GCT_send_prebuilt_message (message, ch->t, NULL,
2388 NULL != existing_copy,
2389 &ch_message_sent, chq);
2390 /* q itself is stored in copy */
2391 GNUNET_assert (NULL != chq->tq || GNUNET_NO != ch->destroy);
2395 fire_and_forget (message, ch, GNUNET_NO);
2400 case GNUNET_MESSAGE_TYPE_CADET_DATA_ACK:
2401 case GNUNET_MESSAGE_TYPE_CADET_CHANNEL_CREATE:
2402 case GNUNET_MESSAGE_TYPE_CADET_CHANNEL_ACK:
2403 chq = GNUNET_new (struct CadetChannelQueue);
2405 chq->rel = fwd ? ch->root_rel : ch->dest_rel;
2406 if (NULL != chq->rel->uniq)
2408 if (NULL != chq->rel->uniq->tq)
2410 GCT_cancel (chq->rel->uniq->tq);
2411 /* ch_message_sent is called, freeing and NULLing uniq */
2412 GNUNET_break (NULL == chq->rel->uniq);
2417 GNUNET_free (chq->rel->uniq);
2421 chq->tq = GCT_send_prebuilt_message (message, ch->t, NULL, GNUNET_YES,
2422 &ch_message_sent, chq);
2423 if (NULL == chq->tq)
2426 GCT_debug (ch->t, GNUNET_ERROR_TYPE_ERROR);
2431 chq->rel->uniq = chq;
2435 case GNUNET_MESSAGE_TYPE_CADET_CHANNEL_DESTROY:
2436 case GNUNET_MESSAGE_TYPE_CADET_CHANNEL_NACK:
2437 fire_and_forget (message, ch, GNUNET_YES);
2443 LOG (GNUNET_ERROR_TYPE_DEBUG, "type %s unknown!\n", GC_m2s (type));
2444 fire_and_forget (message, ch, GNUNET_YES);
2450 * Get the static string for identification of the channel.
2452 * @param ch Channel.
2454 * @return Static string with the channel IDs.
2457 GCCH_2s (const struct CadetChannel *ch)
2459 static char buf[64];
2462 return "(NULL Channel)";
2464 SPRINTF (buf, "%s:%u gid:%X (%X / %X)",
2465 GCT_2s (ch->t), ch->port, ch->gid, ch->lid_root, ch->lid_dest);