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21 * @file cadet/gnunet-service-cadet-new_channel.c
22 * @brief logical links between CADET clients
23 * @author Bartlomiej Polot
24 * @author Christian Grothoff
27 * - Congestion/flow control:
28 * + estimate max bandwidth using bursts and use to for CONGESTION CONTROL!
29 * (and figure out how/where to use this!)
30 * + figure out flow control without ACKs (unreliable traffic!)
31 * - revisit handling of 'unbuffered' traffic!
32 * (need to push down through tunnel into connection selection)
33 * - revisit handling of 'buffered' traffic: 4 is a rather small buffer; maybe
34 * reserve more bits in 'options' to allow for buffer size control?
37 #include "gnunet_util_lib.h"
39 #include "gnunet_statistics_service.h"
40 #include "gnunet-service-cadet-new.h"
41 #include "gnunet-service-cadet-new_channel.h"
42 #include "gnunet-service-cadet-new_connection.h"
43 #include "gnunet-service-cadet-new_tunnels.h"
44 #include "gnunet-service-cadet-new_peer.h"
45 #include "gnunet-service-cadet-new_paths.h"
47 #define LOG(level,...) GNUNET_log_from (level,"cadet-chn",__VA_ARGS__)
50 * How long do we initially wait before retransmitting?
52 #define CADET_INITIAL_RETRANSMIT_TIME GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MILLISECONDS, 250)
55 * How long do we wait before dropping state about incoming
56 * connection to closed port?
58 #define TIMEOUT_CLOSED_PORT GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 30)
61 * How long do we wait at least before retransmitting ever?
63 #define MIN_RTT_DELAY GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MILLISECONDS, 75)
66 * Maximum message ID into the future we accept for out-of-order messages.
67 * If the message is more than this into the future, we drop it. This is
68 * important both to detect values that are actually in the past, as well
69 * as to limit adversarially triggerable memory consumption.
71 * Note that right now we have "max_pending_messages = 4" hard-coded in
72 * the logic below, so a value of 4 would suffice here. But we plan to
73 * allow larger windows in the future...
75 #define MAX_OUT_OF_ORDER_DISTANCE 1024
79 * All the states a channel can be in.
81 enum CadetChannelState
84 * Uninitialized status, should never appear in operation.
89 * Channel is to a port that is not open, we're waiting for the
95 * CHANNEL_OPEN message sent, waiting for CHANNEL_OPEN_ACK.
97 CADET_CHANNEL_OPEN_SENT,
100 * Connection confirmed, ready to carry traffic.
107 * Info needed to retry a message in case it gets lost.
108 * Note that we DO use this structure also for unreliable
111 struct CadetReliableMessage
114 * Double linked list, FIFO style
116 struct CadetReliableMessage *next;
119 * Double linked list, FIFO style
121 struct CadetReliableMessage *prev;
124 * Which channel is this message in?
126 struct CadetChannel *ch;
129 * Entry in the tunnels queue for this message, NULL if it has left
130 * the tunnel. Used to cancel transmission in case we receive an
133 struct CadetTunnelQueueEntry *qe;
136 * Data message we are trying to send.
138 struct GNUNET_CADET_ChannelAppDataMessage *data_message;
141 * How soon should we retry if we fail to get an ACK?
142 * Messages in the queue are sorted by this value.
144 struct GNUNET_TIME_Absolute next_retry;
147 * How long do we wait for an ACK after transmission?
148 * Use for the back-off calculation.
150 struct GNUNET_TIME_Relative retry_delay;
153 * Time when we first successfully transmitted the message
154 * (that is, set @e num_transmissions to 1).
156 struct GNUNET_TIME_Absolute first_transmission_time;
159 * Identifier of the connection that this message took when it
160 * was first transmitted. Only useful if @e num_transmissions is 1.
162 struct GNUNET_CADET_ConnectionTunnelIdentifier connection_taken;
165 * How often was this message transmitted? #GNUNET_SYSERR if there
166 * was an error transmitting the message, #GNUNET_NO if it was not
167 * yet transmitted ever, otherwise the number of (re) transmissions.
169 int num_transmissions;
175 * List of received out-of-order data messages.
177 struct CadetOutOfOrderMessage
180 * Double linked list, FIFO style
182 struct CadetOutOfOrderMessage *next;
185 * Double linked list, FIFO style
187 struct CadetOutOfOrderMessage *prev;
190 * ID of the message (messages up to this point needed
191 * before we give this one to the client).
193 struct ChannelMessageIdentifier mid;
196 * The envelope with the payload of the out-of-order message
198 struct GNUNET_MQ_Envelope *env;
204 * Client endpoint of a `struct CadetChannel`. A channel may be a
205 * loopback channel, in which case it has two of these endpoints.
206 * Note that flow control also is required in both directions.
208 struct CadetChannelClient
211 * Client handle. Not by itself sufficient to designate
212 * the client endpoint, as the same client handle may
213 * be used for both the owner and the destination, and
214 * we thus also need the channel ID to identify the client.
216 struct CadetClient *c;
219 * Head of DLL of messages received out of order or while client was unready.
221 struct CadetOutOfOrderMessage *head_recv;
224 * Tail DLL of messages received out of order or while client was unready.
226 struct CadetOutOfOrderMessage *tail_recv;
229 * Local tunnel number for this client.
230 * (if owner >= #GNUNET_CADET_LOCAL_CHANNEL_ID_CLI,
231 * otherwise < #GNUNET_CADET_LOCAL_CHANNEL_ID_CLI)
233 struct GNUNET_CADET_ClientChannelNumber ccn;
236 * Number of entries currently in @a head_recv DLL.
238 unsigned int num_recv;
241 * Can we send data to the client?
249 * Struct containing all information regarding a channel to a remote client.
254 * Tunnel this channel is in.
256 struct CadetTunnel *t;
259 * Client owner of the tunnel, if any.
260 * (Used if this channel represends the initiating end of the tunnel.)
262 struct CadetChannelClient *owner;
265 * Client destination of the tunnel, if any.
266 * (Used if this channel represents the listening end of the tunnel.)
268 struct CadetChannelClient *dest;
271 * Last entry in the tunnel's queue relating to control messages
272 * (#GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN or
273 * #GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN_ACK). Used to cancel
274 * transmission in case we receive updated information.
276 struct CadetTunnelQueueEntry *last_control_qe;
279 * Head of DLL of messages sent and not yet ACK'd.
281 struct CadetReliableMessage *head_sent;
284 * Tail of DLL of messages sent and not yet ACK'd.
286 struct CadetReliableMessage *tail_sent;
289 * Task to resend/poll in case no ACK is received.
291 struct GNUNET_SCHEDULER_Task *retry_control_task;
294 * Task to resend/poll in case no ACK is received.
296 struct GNUNET_SCHEDULER_Task *retry_data_task;
299 * Last time the channel was used
301 struct GNUNET_TIME_Absolute timestamp;
304 * Destination port of the channel.
306 struct GNUNET_HashCode port;
309 * Counter for exponential backoff.
311 struct GNUNET_TIME_Relative retry_time;
314 * Bitfield of already-received messages past @e mid_recv.
316 uint64_t mid_futures;
319 * Next MID expected for incoming traffic.
321 struct ChannelMessageIdentifier mid_recv;
324 * Next MID to use for outgoing traffic.
326 struct ChannelMessageIdentifier mid_send;
329 * Total (reliable) messages pending ACK for this channel.
331 unsigned int pending_messages;
334 * Maximum (reliable) messages pending ACK for this channel
335 * before we throttle the client.
337 unsigned int max_pending_messages;
340 * Number identifying this channel in its tunnel.
342 struct GNUNET_CADET_ChannelTunnelNumber ctn;
347 enum CadetChannelState state;
350 * Count how many ACKs we skipped, used to prevent long
351 * sequences of ACK skipping.
353 unsigned int skip_ack_series;
356 * Is the tunnel bufferless (minimum latency)?
361 * Is the tunnel reliable?
366 * Is the tunnel out-of-order?
371 * Is this channel a loopback channel, where the destination is us again?
376 * Flag to signal the destruction of the channel. If this is set to
377 * #GNUNET_YES the channel will be destroyed once the queue is
386 * Get the static string for identification of the channel.
390 * @return Static string with the channel IDs.
393 GCCH_2s (const struct CadetChannel *ch)
395 static char buf[128];
397 GNUNET_snprintf (buf,
399 "Channel %s:%s ctn:%X(%X/%X)",
400 (GNUNET_YES == ch->is_loopback)
402 : GNUNET_i2s (GCP_get_id (GCT_get_destination (ch->t))),
403 GNUNET_h2s (&ch->port),
405 (NULL == ch->owner) ? 0 : ntohl (ch->owner->ccn.channel_of_client),
406 (NULL == ch->dest) ? 0 : ntohl (ch->dest->ccn.channel_of_client));
412 * Get the channel's public ID.
416 * @return ID used to identify the channel with the remote peer.
418 struct GNUNET_CADET_ChannelTunnelNumber
419 GCCH_get_id (const struct CadetChannel *ch)
426 * Release memory associated with @a ccc
428 * @param ccc data structure to clean up
431 free_channel_client (struct CadetChannelClient *ccc)
433 struct CadetOutOfOrderMessage *com;
435 while (NULL != (com = ccc->head_recv))
437 GNUNET_CONTAINER_DLL_remove (ccc->head_recv,
441 GNUNET_MQ_discard (com->env);
449 * Destroy the given channel.
451 * @param ch channel to destroy
454 channel_destroy (struct CadetChannel *ch)
456 struct CadetReliableMessage *crm;
458 while (NULL != (crm = ch->head_sent))
460 GNUNET_assert (ch == crm->ch);
463 GCT_send_cancel (crm->qe);
466 GNUNET_CONTAINER_DLL_remove (ch->head_sent,
469 GNUNET_free (crm->data_message);
472 if (NULL != ch->owner)
474 free_channel_client (ch->owner);
477 if (NULL != ch->dest)
479 free_channel_client (ch->dest);
482 if (NULL != ch->last_control_qe)
484 GCT_send_cancel (ch->last_control_qe);
485 ch->last_control_qe = NULL;
487 if (NULL != ch->retry_data_task)
489 GNUNET_SCHEDULER_cancel (ch->retry_data_task);
490 ch->retry_data_task = NULL;
492 if (NULL != ch->retry_control_task)
494 GNUNET_SCHEDULER_cancel (ch->retry_control_task);
495 ch->retry_control_task = NULL;
497 if (GNUNET_NO == ch->is_loopback)
499 GCT_remove_channel (ch->t,
509 * Send a channel create message.
511 * @param cls Channel for which to send.
514 send_channel_open (void *cls);
518 * Function called once the tunnel confirms that we sent the
519 * create message. Delays for a bit until we retry.
521 * @param cls our `struct CadetChannel`.
522 * @param cid identifier of the connection within the tunnel, NULL
523 * if transmission failed
526 channel_open_sent_cb (void *cls,
527 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cid)
529 struct CadetChannel *ch = cls;
531 GNUNET_assert (NULL != ch->last_control_qe);
532 ch->last_control_qe = NULL;
533 ch->retry_time = GNUNET_TIME_STD_BACKOFF (ch->retry_time);
534 LOG (GNUNET_ERROR_TYPE_DEBUG,
535 "Sent CADET_CHANNEL_OPEN on %s, retrying in %s\n",
537 GNUNET_STRINGS_relative_time_to_string (ch->retry_time,
539 ch->retry_control_task
540 = GNUNET_SCHEDULER_add_delayed (ch->retry_time,
547 * Send a channel open message.
549 * @param cls Channel for which to send.
552 send_channel_open (void *cls)
554 struct CadetChannel *ch = cls;
555 struct GNUNET_CADET_ChannelOpenMessage msgcc;
558 ch->retry_control_task = NULL;
559 LOG (GNUNET_ERROR_TYPE_DEBUG,
560 "Sending CHANNEL_OPEN message for %s\n",
564 options |= GNUNET_CADET_OPTION_NOBUFFER;
566 options |= GNUNET_CADET_OPTION_RELIABLE;
567 if (ch->out_of_order)
568 options |= GNUNET_CADET_OPTION_OUT_OF_ORDER;
569 msgcc.header.size = htons (sizeof (msgcc));
570 msgcc.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN);
571 msgcc.opt = htonl (options);
572 msgcc.port = ch->port;
574 ch->state = CADET_CHANNEL_OPEN_SENT;
575 if (NULL != ch->last_control_qe)
576 GCT_send_cancel (ch->last_control_qe);
577 ch->last_control_qe = GCT_send (ch->t,
579 &channel_open_sent_cb,
581 GNUNET_assert (NULL == ch->retry_control_task);
586 * Function called once and only once after a channel was bound
587 * to its tunnel via #GCT_add_channel() is ready for transmission.
588 * Note that this is only the case for channels that this peer
589 * initiates, as for incoming channels we assume that they are
590 * ready for transmission immediately upon receiving the open
591 * message. Used to bootstrap the #GCT_send() process.
593 * @param ch the channel for which the tunnel is now ready
596 GCCH_tunnel_up (struct CadetChannel *ch)
598 GNUNET_assert (NULL == ch->retry_control_task);
599 LOG (GNUNET_ERROR_TYPE_DEBUG,
600 "Tunnel up, sending CHANNEL_OPEN on %s now\n",
602 ch->retry_control_task
603 = GNUNET_SCHEDULER_add_now (&send_channel_open,
609 * Create a new channel.
611 * @param owner local client owning the channel
612 * @param ccn local number of this channel at the @a owner
613 * @param destination peer to which we should build the channel
614 * @param port desired port at @a destination
615 * @param options options for the channel
616 * @return handle to the new channel
618 struct CadetChannel *
619 GCCH_channel_local_new (struct CadetClient *owner,
620 struct GNUNET_CADET_ClientChannelNumber ccn,
621 struct CadetPeer *destination,
622 const struct GNUNET_HashCode *port,
625 struct CadetChannel *ch;
626 struct CadetChannelClient *ccco;
628 ccco = GNUNET_new (struct CadetChannelClient);
631 ccco->client_ready = GNUNET_YES;
633 ch = GNUNET_new (struct CadetChannel);
634 ch->mid_recv.mid = htonl (1); /* The OPEN_ACK counts as message 0! */
635 ch->nobuffer = (0 != (options & GNUNET_CADET_OPTION_NOBUFFER));
636 ch->reliable = (0 != (options & GNUNET_CADET_OPTION_RELIABLE));
637 ch->out_of_order = (0 != (options & GNUNET_CADET_OPTION_OUT_OF_ORDER));
638 ch->max_pending_messages = (ch->nobuffer) ? 1 : 4; /* FIXME: 4!? Do not hardcode! */
641 if (0 == memcmp (&my_full_id,
642 GCP_get_id (destination),
643 sizeof (struct GNUNET_PeerIdentity)))
645 struct CadetClient *c;
647 ch->is_loopback = GNUNET_YES;
648 c = GNUNET_CONTAINER_multihashmap_get (open_ports,
652 /* port closed, wait for it to possibly open */
653 ch->state = CADET_CHANNEL_LOOSE;
654 (void) GNUNET_CONTAINER_multihashmap_put (loose_channels,
657 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
658 LOG (GNUNET_ERROR_TYPE_DEBUG,
659 "Created loose incoming loopback channel to port %s\n",
660 GNUNET_h2s (&ch->port));
670 ch->t = GCP_get_tunnel (destination,
672 ch->retry_time = CADET_INITIAL_RETRANSMIT_TIME;
673 ch->ctn = GCT_add_channel (ch->t,
676 GNUNET_STATISTICS_update (stats,
680 LOG (GNUNET_ERROR_TYPE_DEBUG,
681 "Created channel to port %s at peer %s for %s using %s\n",
683 GCP_2s (destination),
685 (GNUNET_YES == ch->is_loopback) ? "loopback" : GCT_2s (ch->t));
691 * We had an incoming channel to a port that is closed.
692 * It has not been opened for a while, drop it.
694 * @param cls the channel to drop
697 timeout_closed_cb (void *cls)
699 struct CadetChannel *ch = cls;
701 ch->retry_control_task = NULL;
702 LOG (GNUNET_ERROR_TYPE_DEBUG,
703 "Closing incoming channel to port %s from peer %s due to timeout\n",
704 GNUNET_h2s (&ch->port),
705 GCP_2s (GCT_get_destination (ch->t)));
706 channel_destroy (ch);
711 * Create a new channel based on a request coming in over the network.
713 * @param t tunnel to the remote peer
714 * @param ctn identifier of this channel in the tunnel
715 * @param port desired local port
716 * @param options options for the channel
717 * @return handle to the new channel
719 struct CadetChannel *
720 GCCH_channel_incoming_new (struct CadetTunnel *t,
721 struct GNUNET_CADET_ChannelTunnelNumber ctn,
722 const struct GNUNET_HashCode *port,
725 struct CadetChannel *ch;
726 struct CadetClient *c;
728 ch = GNUNET_new (struct CadetChannel);
732 ch->retry_time = CADET_INITIAL_RETRANSMIT_TIME;
733 ch->nobuffer = (0 != (options & GNUNET_CADET_OPTION_NOBUFFER));
734 ch->reliable = (0 != (options & GNUNET_CADET_OPTION_RELIABLE));
735 ch->out_of_order = (0 != (options & GNUNET_CADET_OPTION_OUT_OF_ORDER));
736 ch->max_pending_messages = (ch->nobuffer) ? 1 : 4; /* FIXME: 4!? Do not hardcode! */
737 GNUNET_STATISTICS_update (stats,
742 c = GNUNET_CONTAINER_multihashmap_get (open_ports,
746 /* port closed, wait for it to possibly open */
747 ch->state = CADET_CHANNEL_LOOSE;
748 (void) GNUNET_CONTAINER_multihashmap_put (loose_channels,
751 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
752 GNUNET_assert (NULL == ch->retry_control_task);
753 ch->retry_control_task
754 = GNUNET_SCHEDULER_add_delayed (TIMEOUT_CLOSED_PORT,
757 LOG (GNUNET_ERROR_TYPE_DEBUG,
758 "Created loose incoming channel to port %s from peer %s\n",
759 GNUNET_h2s (&ch->port),
760 GCP_2s (GCT_get_destination (ch->t)));
767 GNUNET_STATISTICS_update (stats,
776 * Function called once the tunnel confirms that we sent the
777 * ACK message. Just remembers it was sent, we do not expect
780 * @param cls our `struct CadetChannel`.
781 * @param cid identifier of the connection within the tunnel, NULL
782 * if transmission failed
785 send_ack_cb (void *cls,
786 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cid)
788 struct CadetChannel *ch = cls;
790 GNUNET_assert (NULL != ch->last_control_qe);
791 ch->last_control_qe = NULL;
796 * Compute and send the current #GNUNET_MESSAGE_TYPE_CADET_CHANNEL_APP_DATA_ACK to the other peer.
798 * @param ch channel to send the #GNUNET_MESSAGE_TYPE_CADET_CHANNEL_APP_DATA_ACK for
801 send_channel_data_ack (struct CadetChannel *ch)
803 struct GNUNET_CADET_ChannelDataAckMessage msg;
805 if (GNUNET_NO == ch->reliable)
806 return; /* no ACKs */
807 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CHANNEL_APP_DATA_ACK);
808 msg.header.size = htons (sizeof (msg));
810 msg.mid.mid = htonl (ntohl (ch->mid_recv.mid));
811 msg.futures = GNUNET_htonll (ch->mid_futures);
812 LOG (GNUNET_ERROR_TYPE_DEBUG,
813 "Sending DATA_ACK %u:%llX via %s\n",
814 (unsigned int) ntohl (msg.mid.mid),
815 (unsigned long long) ch->mid_futures,
817 if (NULL != ch->last_control_qe)
818 GCT_send_cancel (ch->last_control_qe);
819 ch->last_control_qe = GCT_send (ch->t,
827 * Send our initial #GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN_ACK to the client confirming that the
830 * @param cls the `struct CadetChannel`
833 send_open_ack (void *cls)
835 struct CadetChannel *ch = cls;
836 struct GNUNET_CADET_ChannelManageMessage msg;
838 ch->retry_control_task = NULL;
839 LOG (GNUNET_ERROR_TYPE_DEBUG,
840 "Sending CHANNEL_OPEN_ACK on %s\n",
842 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN_ACK);
843 msg.header.size = htons (sizeof (msg));
844 msg.reserved = htonl (0);
846 if (NULL != ch->last_control_qe)
847 GCT_send_cancel (ch->last_control_qe);
848 ch->last_control_qe = GCT_send (ch->t,
856 * We got a #GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN message again for
857 * this channel. If the binding was successful, (re)transmit the
858 * #GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN_ACK.
860 * @param ch channel that got the duplicate open
861 * @param cti identifier of the connection that delivered the message
864 GCCH_handle_duplicate_open (struct CadetChannel *ch,
865 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti)
867 if (NULL == ch->dest)
869 LOG (GNUNET_ERROR_TYPE_DEBUG,
870 "Ignoring duplicate CHANNEL_OPEN on %s: port is closed\n",
874 if (NULL != ch->retry_control_task)
876 LOG (GNUNET_ERROR_TYPE_DEBUG,
877 "Ignoring duplicate CHANNEL_OPEN on %s: control message is pending\n",
881 LOG (GNUNET_ERROR_TYPE_DEBUG,
882 "Retransmitting CHANNEL_OPEN_ACK on %s\n",
884 ch->retry_control_task
885 = GNUNET_SCHEDULER_add_now (&send_open_ack,
891 * Send a #GNUNET_MESSAGE_TYPE_CADET_LOCAL_ACK to the client to solicit more messages.
893 * @param ch channel the ack is for
894 * @param to_owner #GNUNET_YES to send to owner,
895 * #GNUNET_NO to send to dest
898 send_ack_to_client (struct CadetChannel *ch,
901 struct GNUNET_MQ_Envelope *env;
902 struct GNUNET_CADET_LocalAck *ack;
903 struct CadetChannelClient *ccc;
905 ccc = (GNUNET_YES == to_owner) ? ch->owner : ch->dest;
908 /* This can happen if we are just getting ACKs after
909 our local client already disconnected. */
910 GNUNET_assert (GNUNET_YES == ch->destroy);
913 env = GNUNET_MQ_msg (ack,
914 GNUNET_MESSAGE_TYPE_CADET_LOCAL_ACK);
916 LOG (GNUNET_ERROR_TYPE_DEBUG,
917 "Sending CADET_LOCAL_ACK to %s (%s) at ccn %X (%u/%u pending)\n",
919 (GNUNET_YES == to_owner) ? "owner" : "dest",
920 ntohl (ack->ccn.channel_of_client),
921 ch->pending_messages,
922 ch->max_pending_messages);
923 GSC_send_to_client (ccc->c,
929 * A client is bound to the port that we have a channel
930 * open to. Send the acknowledgement for the connection
931 * request and establish the link with the client.
933 * @param ch open incoming channel
934 * @param c client listening on the respective port
937 GCCH_bind (struct CadetChannel *ch,
938 struct CadetClient *c)
941 struct CadetChannelClient *cccd;
943 LOG (GNUNET_ERROR_TYPE_DEBUG,
944 "Binding %s from %s to port %s of %s\n",
947 GNUNET_h2s (&ch->port),
949 if (NULL != ch->retry_control_task)
951 /* there might be a timeout task here */
952 GNUNET_SCHEDULER_cancel (ch->retry_control_task);
953 ch->retry_control_task = NULL;
957 options |= GNUNET_CADET_OPTION_NOBUFFER;
959 options |= GNUNET_CADET_OPTION_RELIABLE;
960 if (ch->out_of_order)
961 options |= GNUNET_CADET_OPTION_OUT_OF_ORDER;
962 cccd = GNUNET_new (struct CadetChannelClient);
963 GNUNET_assert (NULL == ch->dest);
966 cccd->client_ready = GNUNET_YES;
967 cccd->ccn = GSC_bind (c,
969 (GNUNET_YES == ch->is_loopback)
970 ? GCP_get (&my_full_id,
972 : GCT_get_destination (ch->t),
975 GNUNET_assert (ntohl (cccd->ccn.channel_of_client) <
976 GNUNET_CADET_LOCAL_CHANNEL_ID_CLI);
977 ch->mid_recv.mid = htonl (1); /* The OPEN counts as message 0! */
978 if (GNUNET_YES == ch->is_loopback)
980 ch->state = CADET_CHANNEL_OPEN_SENT;
981 GCCH_handle_channel_open_ack (ch,
986 /* notify other peer that we accepted the connection */
987 ch->state = CADET_CHANNEL_READY;
988 ch->retry_control_task
989 = GNUNET_SCHEDULER_add_now (&send_open_ack,
992 /* give client it's initial supply of ACKs */
993 GNUNET_assert (ntohl (cccd->ccn.channel_of_client) <
994 GNUNET_CADET_LOCAL_CHANNEL_ID_CLI);
995 for (unsigned int i=0;i<ch->max_pending_messages;i++)
996 send_ack_to_client (ch,
1002 * One of our clients has disconnected, tell the other one that we
1003 * are finished. Done asynchronously to avoid concurrent modification
1004 * issues if this is the same client.
1006 * @param cls the `struct CadetChannel` where one of the ends is now dead
1009 signal_remote_destroy_cb (void *cls)
1011 struct CadetChannel *ch = cls;
1012 struct CadetChannelClient *ccc;
1014 /* Find which end is left... */
1015 ch->retry_control_task = NULL;
1016 ccc = (NULL != ch->owner) ? ch->owner : ch->dest;
1017 GSC_handle_remote_channel_destroy (ccc->c,
1020 channel_destroy (ch);
1025 * Destroy locally created channel. Called by the local client, so no
1026 * need to tell the client.
1028 * @param ch channel to destroy
1029 * @param c client that caused the destruction
1030 * @param ccn client number of the client @a c
1033 GCCH_channel_local_destroy (struct CadetChannel *ch,
1034 struct CadetClient *c,
1035 struct GNUNET_CADET_ClientChannelNumber ccn)
1037 LOG (GNUNET_ERROR_TYPE_DEBUG,
1038 "%s asks for destruction of %s\n",
1041 GNUNET_assert (NULL != c);
1042 if ( (NULL != ch->owner) &&
1043 (c == ch->owner->c) &&
1044 (ccn.channel_of_client == ch->owner->ccn.channel_of_client) )
1046 free_channel_client (ch->owner);
1049 else if ( (NULL != ch->dest) &&
1050 (c == ch->dest->c) &&
1051 (ccn.channel_of_client == ch->dest->ccn.channel_of_client) )
1053 free_channel_client (ch->dest);
1061 if (GNUNET_YES == ch->destroy)
1063 /* other end already destroyed, with the local client gone, no need
1064 to finish transmissions, just destroy immediately. */
1065 channel_destroy (ch);
1068 if ( (NULL != ch->head_sent) &&
1069 ( (NULL != ch->owner) ||
1070 (NULL != ch->dest) ) )
1072 /* Wait for other end to destroy us as well,
1073 and otherwise allow send queue to be transmitted first */
1074 ch->destroy = GNUNET_YES;
1077 if ( (GNUNET_YES == ch->is_loopback) &&
1078 ( (NULL != ch->owner) ||
1079 (NULL != ch->dest) ) )
1081 if (NULL != ch->retry_control_task)
1082 GNUNET_SCHEDULER_cancel (ch->retry_control_task);
1083 ch->retry_control_task
1084 = GNUNET_SCHEDULER_add_now (&signal_remote_destroy_cb,
1088 if (GNUNET_NO == ch->is_loopback)
1090 /* If the we ever sent the CHANNEL_CREATE, we need to send a destroy message. */
1093 case CADET_CHANNEL_NEW:
1094 /* We gave up on a channel that we created as a client to a remote
1095 target, but that never went anywhere. Nothing to do here. */
1097 case CADET_CHANNEL_LOOSE:
1098 GSC_drop_loose_channel (&ch->port,
1102 GCT_send_channel_destroy (ch->t,
1106 /* Nothing left to do, just finish destruction */
1107 channel_destroy (ch);
1112 * We got an acknowledgement for the creation of the channel
1113 * (the port is open on the other side). Begin transmissions.
1115 * @param ch channel to destroy
1116 * @param cti identifier of the connection that delivered the message
1119 GCCH_handle_channel_open_ack (struct CadetChannel *ch,
1120 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti)
1124 case CADET_CHANNEL_NEW:
1125 /* this should be impossible */
1128 case CADET_CHANNEL_LOOSE:
1129 /* This makes no sense. */
1130 GNUNET_break_op (0);
1132 case CADET_CHANNEL_OPEN_SENT:
1133 if (NULL == ch->owner)
1135 /* We're not the owner, wrong direction! */
1136 GNUNET_break_op (0);
1139 LOG (GNUNET_ERROR_TYPE_DEBUG,
1140 "Received CHANNEL_OPEN_ACK for waiting %s, entering READY state\n",
1142 if (NULL != ch->retry_control_task) /* can be NULL if ch->is_loopback */
1144 GNUNET_SCHEDULER_cancel (ch->retry_control_task);
1145 ch->retry_control_task = NULL;
1147 ch->state = CADET_CHANNEL_READY;
1148 /* On first connect, send client as many ACKs as we allow messages
1150 for (unsigned int i=0;i<ch->max_pending_messages;i++)
1151 send_ack_to_client (ch,
1154 case CADET_CHANNEL_READY:
1155 /* duplicate ACK, maybe we retried the CREATE. Ignore. */
1156 LOG (GNUNET_ERROR_TYPE_DEBUG,
1157 "Received duplicate channel OPEN_ACK for %s\n",
1159 GNUNET_STATISTICS_update (stats,
1160 "# duplicate CREATE_ACKs",
1169 * Test if element @a e1 comes before element @a e2.
1171 * @param cls closure, to a flag where we indicate duplicate packets
1172 * @param m1 a message of to sort
1173 * @param m2 another message to sort
1174 * @return #GNUNET_YES if @e1 < @e2, otherwise #GNUNET_NO
1177 is_before (void *cls,
1178 struct CadetOutOfOrderMessage *m1,
1179 struct CadetOutOfOrderMessage *m2)
1181 int *duplicate = cls;
1182 uint32_t v1 = ntohl (m1->mid.mid);
1183 uint32_t v2 = ntohl (m2->mid.mid);
1188 *duplicate = GNUNET_YES;
1189 if (delta > (uint32_t) INT_MAX)
1191 /* in overflow range, we can safely assume we wrapped around */
1196 /* result is small, thus v2 > v1, thus m1 < m2 */
1203 * We got payload data for a channel. Pass it on to the client
1204 * and send an ACK to the other end (once flow control allows it!)
1206 * @param ch channel that got data
1207 * @param cti identifier of the connection that delivered the message
1208 * @param msg message that was received
1211 GCCH_handle_channel_plaintext_data (struct CadetChannel *ch,
1212 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti,
1213 const struct GNUNET_CADET_ChannelAppDataMessage *msg)
1215 struct GNUNET_MQ_Envelope *env;
1216 struct GNUNET_CADET_LocalData *ld;
1217 struct CadetChannelClient *ccc;
1218 size_t payload_size;
1219 struct CadetOutOfOrderMessage *com;
1226 GNUNET_assert (GNUNET_NO == ch->is_loopback);
1227 if ( (GNUNET_YES == ch->destroy) &&
1228 (NULL == ch->owner) &&
1229 (NULL == ch->dest) )
1231 /* This client is gone, but we still have messages to send to
1232 the other end (which is why @a ch is not yet dead). However,
1233 we cannot pass messages to our client anymore. */
1234 LOG (GNUNET_ERROR_TYPE_DEBUG,
1235 "Dropping incoming payload on %s as this end is already closed\n",
1237 /* send back DESTROY notification to stop further retransmissions! */
1238 GCT_send_channel_destroy (ch->t,
1242 payload_size = ntohs (msg->header.size) - sizeof (*msg);
1243 env = GNUNET_MQ_msg_extra (ld,
1245 GNUNET_MESSAGE_TYPE_CADET_LOCAL_DATA);
1246 ld->ccn = (NULL == ch->dest) ? ch->owner->ccn : ch->dest->ccn;
1247 GNUNET_memcpy (&ld[1],
1250 ccc = (NULL != ch->owner) ? ch->owner : ch->dest;
1251 if ( (GNUNET_YES == ccc->client_ready) &&
1252 ( (GNUNET_YES == ch->out_of_order) ||
1253 (msg->mid.mid == ch->mid_recv.mid) ) )
1255 LOG (GNUNET_ERROR_TYPE_DEBUG,
1256 "Giving %u bytes of payload with MID %u from %s to client %s\n",
1257 (unsigned int) payload_size,
1258 ntohl (msg->mid.mid),
1261 ccc->client_ready = GNUNET_NO;
1262 GSC_send_to_client (ccc->c,
1264 ch->mid_recv.mid = htonl (1 + ntohl (ch->mid_recv.mid));
1265 ch->mid_futures >>= 1;
1266 send_channel_data_ack (ch);
1270 if (GNUNET_YES == ch->reliable)
1272 /* check if message ought to be dropped because it is ancient/too distant/duplicate */
1273 mid_min = ntohl (ch->mid_recv.mid);
1274 mid_max = mid_min + ch->max_pending_messages;
1275 mid_msg = ntohl (msg->mid.mid);
1276 if ( ( (uint32_t) (mid_msg - mid_min) > ch->max_pending_messages) ||
1277 ( (uint32_t) (mid_max - mid_msg) > ch->max_pending_messages) )
1279 LOG (GNUNET_ERROR_TYPE_DEBUG,
1280 "%s at %u drops ancient or far-future message %u\n",
1282 (unsigned int) mid_min,
1283 ntohl (msg->mid.mid));
1285 GNUNET_STATISTICS_update (stats,
1286 "# duplicate DATA (ancient or future)",
1289 GNUNET_MQ_discard (env);
1290 send_channel_data_ack (ch);
1293 /* mark bit for future ACKs */
1294 delta = mid_msg - mid_min - 1; /* overflow/underflow are OK here */
1297 if (0 != (ch->mid_futures & (1LLU << delta)))
1299 /* Duplicate within the queue, drop also */
1300 LOG (GNUNET_ERROR_TYPE_DEBUG,
1301 "Duplicate payload of %u bytes on %s (mid %u) dropped\n",
1302 (unsigned int) payload_size,
1304 ntohl (msg->mid.mid));
1305 GNUNET_STATISTICS_update (stats,
1309 GNUNET_MQ_discard (env);
1310 send_channel_data_ack (ch);
1313 ch->mid_futures |= (1LLU << delta);
1314 LOG (GNUNET_ERROR_TYPE_DEBUG,
1315 "Marked bit %llX for mid %u (base: %u); now: %llX\n",
1322 else /* ! ch->reliable */
1324 /* Channel is unreliable, so we do not ACK. But we also cannot
1325 allow buffering everything, so check if we have space... */
1326 if (ccc->num_recv >= ch->max_pending_messages)
1328 struct CadetOutOfOrderMessage *drop;
1330 /* Yep, need to drop. Drop the oldest message in
1332 LOG (GNUNET_ERROR_TYPE_DEBUG,
1333 "Queue full due slow client on %s, dropping oldest message\n",
1335 GNUNET_STATISTICS_update (stats,
1336 "# messages dropped due to slow client",
1339 drop = ccc->head_recv;
1340 GNUNET_CONTAINER_DLL_remove (ccc->head_recv,
1344 GNUNET_MQ_discard (drop->env);
1349 /* Insert message into sorted out-of-order queue */
1350 com = GNUNET_new (struct CadetOutOfOrderMessage);
1351 com->mid = msg->mid;
1353 duplicate = GNUNET_NO;
1354 GNUNET_CONTAINER_DLL_insert_sorted (struct CadetOutOfOrderMessage,
1361 if (GNUNET_YES == duplicate)
1363 /* Duplicate within the queue, drop also (this is not covered by
1364 the case above if "delta" >= 64, which could be the case if
1365 max_pending_messages is also >= 64 or if our client is unready
1366 and we are seeing retransmissions of the message our client is
1368 LOG (GNUNET_ERROR_TYPE_DEBUG,
1369 "Duplicate payload of %u bytes on %s (mid %u) dropped\n",
1370 (unsigned int) payload_size,
1372 ntohl (msg->mid.mid));
1373 GNUNET_STATISTICS_update (stats,
1377 GNUNET_CONTAINER_DLL_remove (ccc->head_recv,
1381 GNUNET_MQ_discard (com->env);
1383 send_channel_data_ack (ch);
1386 LOG (GNUNET_ERROR_TYPE_DEBUG,
1387 "Queued %s payload of %u bytes on %s-%X(%p) (mid %u, need %u first)\n",
1388 (GNUNET_YES == ccc->client_ready)
1390 : "client-not-ready",
1391 (unsigned int) payload_size,
1393 ntohl (ccc->ccn.channel_of_client),
1395 ntohl (msg->mid.mid),
1396 ntohl (ch->mid_recv.mid));
1397 /* NOTE: this ACK we _could_ skip, as the packet is out-of-order and
1398 the sender may already be transmitting the previous one. Needs
1399 experimental evaluation to see if/when this ACK helps or
1400 hurts. (We might even want another option.) */
1401 send_channel_data_ack (ch);
1406 * Function called once the tunnel has sent one of our messages.
1407 * If the message is unreliable, simply frees the `crm`. If the
1408 * message was reliable, calculate retransmission time and
1409 * wait for ACK (or retransmit).
1411 * @param cls the `struct CadetReliableMessage` that was sent
1412 * @param cid identifier of the connection within the tunnel, NULL
1413 * if transmission failed
1416 data_sent_cb (void *cls,
1417 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cid);
1421 * We need to retry a transmission, the last one took too long to
1424 * @param cls the `struct CadetChannel` where we need to retransmit
1427 retry_transmission (void *cls)
1429 struct CadetChannel *ch = cls;
1430 struct CadetReliableMessage *crm = ch->head_sent;
1432 ch->retry_data_task = NULL;
1433 GNUNET_assert (NULL == crm->qe);
1434 LOG (GNUNET_ERROR_TYPE_DEBUG,
1435 "Retrying transmission on %s of message %u\n",
1437 (unsigned int) ntohl (crm->data_message->mid.mid));
1438 crm->qe = GCT_send (ch->t,
1439 &crm->data_message->header,
1442 GNUNET_assert (NULL == ch->retry_data_task);
1447 * We got an PLAINTEXT_DATA_ACK for a message in our queue, remove it from
1448 * the queue and tell our client that it can send more.
1450 * @param ch the channel that got the PLAINTEXT_DATA_ACK
1451 * @param cti identifier of the connection that delivered the message
1452 * @param crm the message that got acknowledged
1455 handle_matching_ack (struct CadetChannel *ch,
1456 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti,
1457 struct CadetReliableMessage *crm)
1459 GNUNET_CONTAINER_DLL_remove (ch->head_sent,
1462 ch->pending_messages--;
1463 GNUNET_assert (ch->pending_messages < ch->max_pending_messages);
1464 LOG (GNUNET_ERROR_TYPE_DEBUG,
1465 "Received DATA_ACK on %s for message %u (%u ACKs pending)\n",
1467 (unsigned int) ntohl (crm->data_message->mid.mid),
1468 ch->pending_messages);
1469 if (NULL != crm->qe)
1471 GCT_send_cancel (crm->qe);
1474 if ( (1 == crm->num_transmissions) &&
1477 GCC_ack_observed (cti);
1478 if (0 == memcmp (cti,
1479 &crm->connection_taken,
1480 sizeof (struct GNUNET_CADET_ConnectionTunnelIdentifier)))
1482 GCC_latency_observed (cti,
1483 GNUNET_TIME_absolute_get_duration (crm->first_transmission_time));
1486 GNUNET_free (crm->data_message);
1488 send_ack_to_client (ch,
1496 * We got an acknowledgement for payload data for a channel.
1497 * Possibly resume transmissions.
1499 * @param ch channel that got the ack
1500 * @param cti identifier of the connection that delivered the message
1501 * @param ack details about what was received
1504 GCCH_handle_channel_plaintext_data_ack (struct CadetChannel *ch,
1505 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti,
1506 const struct GNUNET_CADET_ChannelDataAckMessage *ack)
1508 struct CadetReliableMessage *crm;
1509 struct CadetReliableMessage *crmn;
1515 GNUNET_break (GNUNET_NO == ch->is_loopback);
1516 if (GNUNET_NO == ch->reliable)
1518 /* not expecting ACKs on unreliable channel, odd */
1519 GNUNET_break_op (0);
1522 /* mid_base is the MID of the next message that the
1523 other peer expects (i.e. that is missing!), everything
1524 LOWER (but excluding mid_base itself) was received. */
1525 mid_base = ntohl (ack->mid.mid);
1526 mid_mask = GNUNET_htonll (ack->futures);
1528 for (crm = ch->head_sent;
1533 delta = (unsigned int) (ntohl (crm->data_message->mid.mid) - mid_base);
1534 if (delta >= UINT_MAX - ch->max_pending_messages)
1536 /* overflow, means crm was a bit in the past, so this ACK counts for it. */
1537 LOG (GNUNET_ERROR_TYPE_DEBUG,
1538 "Got DATA_ACK with base %u satisfying past message %u on %s\n",
1539 (unsigned int) mid_base,
1540 ntohl (crm->data_message->mid.mid),
1542 handle_matching_ack (ch,
1551 LOG (GNUNET_ERROR_TYPE_DEBUG,
1552 "Testing bit %llX for mid %u (base: %u)\n",
1554 ntohl (crm->data_message->mid.mid),
1556 if (0 != (mid_mask & (1LLU << delta)))
1558 LOG (GNUNET_ERROR_TYPE_DEBUG,
1559 "Got DATA_ACK with mask for %u on %s\n",
1560 ntohl (crm->data_message->mid.mid),
1562 handle_matching_ack (ch,
1568 if (GNUNET_NO == found)
1570 /* ACK for message we already dropped, might have been a
1571 duplicate ACK? Ignore. */
1572 LOG (GNUNET_ERROR_TYPE_DEBUG,
1573 "Duplicate DATA_ACK on %s, ignoring\n",
1575 GNUNET_STATISTICS_update (stats,
1576 "# duplicate DATA_ACKs",
1581 if (NULL != ch->retry_data_task)
1583 GNUNET_SCHEDULER_cancel (ch->retry_data_task);
1584 ch->retry_data_task = NULL;
1586 if ( (NULL != ch->head_sent) &&
1587 (NULL == ch->head_sent->qe) )
1589 = GNUNET_SCHEDULER_add_at (ch->head_sent->next_retry,
1590 &retry_transmission,
1596 * Destroy channel, based on the other peer closing the
1597 * connection. Also needs to remove this channel from
1600 * @param ch channel to destroy
1601 * @param cti identifier of the connection that delivered the message,
1602 * NULL if we are simulating receiving a destroy due to shutdown
1605 GCCH_handle_remote_destroy (struct CadetChannel *ch,
1606 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti)
1608 struct CadetChannelClient *ccc;
1610 GNUNET_assert (GNUNET_NO == ch->is_loopback);
1611 LOG (GNUNET_ERROR_TYPE_DEBUG,
1612 "Received remote channel DESTROY for %s\n",
1614 if (GNUNET_YES == ch->destroy)
1616 /* Local client already gone, this is instant-death. */
1617 channel_destroy (ch);
1620 ccc = (NULL != ch->owner) ? ch->owner : ch->dest;
1621 if ( (NULL != ccc) &&
1622 (NULL != ccc->head_recv) )
1624 LOG (GNUNET_ERROR_TYPE_WARNING,
1625 "Lost end of transmission due to remote shutdown on %s\n",
1627 /* FIXME: change API to notify client about truncated transmission! */
1629 ch->destroy = GNUNET_YES;
1631 GSC_handle_remote_channel_destroy (ccc->c,
1634 channel_destroy (ch);
1639 * Test if element @a e1 comes before element @a e2.
1641 * @param cls closure, to a flag where we indicate duplicate packets
1642 * @param crm1 an element of to sort
1643 * @param crm2 another element to sort
1644 * @return #GNUNET_YES if @e1 < @e2, otherwise #GNUNET_NO
1647 cmp_crm_by_next_retry (void *cls,
1648 struct CadetReliableMessage *crm1,
1649 struct CadetReliableMessage *crm2)
1651 if (crm1->next_retry.abs_value_us <
1652 crm2->next_retry.abs_value_us)
1659 * Function called once the tunnel has sent one of our messages.
1660 * If the message is unreliable, simply frees the `crm`. If the
1661 * message was reliable, calculate retransmission time and
1662 * wait for ACK (or retransmit).
1664 * @param cls the `struct CadetReliableMessage` that was sent
1665 * @param cid identifier of the connection within the tunnel, NULL
1666 * if transmission failed
1669 data_sent_cb (void *cls,
1670 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cid)
1672 struct CadetReliableMessage *crm = cls;
1673 struct CadetChannel *ch = crm->ch;
1675 GNUNET_assert (GNUNET_NO == ch->is_loopback);
1676 GNUNET_assert (NULL != crm->qe);
1678 GNUNET_CONTAINER_DLL_remove (ch->head_sent,
1681 if (GNUNET_NO == ch->reliable)
1683 GNUNET_free (crm->data_message);
1685 ch->pending_messages--;
1686 send_ack_to_client (ch,
1694 /* There was an error sending. */
1695 crm->num_transmissions = GNUNET_SYSERR;
1697 else if (GNUNET_SYSERR != crm->num_transmissions)
1699 /* Increment transmission counter, and possibly store @a cid
1700 if this was the first transmission. */
1701 crm->num_transmissions++;
1702 if (1 == crm->num_transmissions)
1704 crm->first_transmission_time = GNUNET_TIME_absolute_get ();
1705 crm->connection_taken = *cid;
1706 GCC_ack_expected (cid);
1709 if ( (0 == crm->retry_delay.rel_value_us) &&
1712 struct CadetConnection *cc = GCC_lookup (cid);
1715 crm->retry_delay = GCC_get_metrics (cc)->aged_latency;
1717 crm->retry_delay = ch->retry_time;
1719 crm->retry_delay = GNUNET_TIME_STD_BACKOFF (crm->retry_delay);
1720 crm->retry_delay = GNUNET_TIME_relative_max (crm->retry_delay,
1722 crm->next_retry = GNUNET_TIME_relative_to_absolute (crm->retry_delay);
1724 GNUNET_CONTAINER_DLL_insert_sorted (struct CadetReliableMessage,
1725 cmp_crm_by_next_retry,
1730 LOG (GNUNET_ERROR_TYPE_DEBUG,
1731 "Message %u sent, next transmission on %s in %s\n",
1732 (unsigned int) ntohl (crm->data_message->mid.mid),
1734 GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_remaining (ch->head_sent->next_retry),
1736 if (NULL == ch->head_sent->qe)
1738 if (NULL != ch->retry_data_task)
1739 GNUNET_SCHEDULER_cancel (ch->retry_data_task);
1741 = GNUNET_SCHEDULER_add_at (ch->head_sent->next_retry,
1742 &retry_transmission,
1749 * Handle data given by a client.
1751 * Check whether the client is allowed to send in this tunnel, save if
1752 * channel is reliable and send an ACK to the client if there is still
1753 * buffer space in the tunnel.
1755 * @param ch Channel.
1756 * @param sender_ccn ccn of the sender
1757 * @param buf payload to transmit.
1758 * @param buf_len number of bytes in @a buf
1759 * @return #GNUNET_OK if everything goes well,
1760 * #GNUNET_SYSERR in case of an error.
1763 GCCH_handle_local_data (struct CadetChannel *ch,
1764 struct GNUNET_CADET_ClientChannelNumber sender_ccn,
1768 struct CadetReliableMessage *crm;
1770 if (ch->pending_messages > ch->max_pending_messages)
1773 return GNUNET_SYSERR;
1775 if (GNUNET_YES == ch->destroy)
1777 /* we are going down, drop messages */
1780 ch->pending_messages++;
1782 if (GNUNET_YES == ch->is_loopback)
1784 struct CadetChannelClient *receiver;
1785 struct GNUNET_MQ_Envelope *env;
1786 struct GNUNET_CADET_LocalData *ld;
1789 env = GNUNET_MQ_msg_extra (ld,
1791 GNUNET_MESSAGE_TYPE_CADET_LOCAL_DATA);
1792 if ( (NULL != ch->owner) &&
1793 (sender_ccn.channel_of_client ==
1794 ch->owner->ccn.channel_of_client) )
1796 receiver = ch->dest;
1797 ack_to_owner = GNUNET_YES;
1799 else if ( (NULL != ch->dest) &&
1800 (sender_ccn.channel_of_client ==
1801 ch->dest->ccn.channel_of_client) )
1803 receiver = ch->owner;
1804 ack_to_owner = GNUNET_NO;
1809 return GNUNET_SYSERR;
1811 ld->ccn = receiver->ccn;
1812 GNUNET_memcpy (&ld[1],
1815 if (GNUNET_YES == receiver->client_ready)
1817 ch->pending_messages--;
1818 GSC_send_to_client (receiver->c,
1820 send_ack_to_client (ch,
1825 struct CadetOutOfOrderMessage *oom;
1827 oom = GNUNET_new (struct CadetOutOfOrderMessage);
1829 GNUNET_CONTAINER_DLL_insert_tail (receiver->head_recv,
1830 receiver->tail_recv,
1832 receiver->num_recv++;
1837 /* Everything is correct, send the message. */
1838 crm = GNUNET_malloc (sizeof (*crm));
1840 crm->data_message = GNUNET_malloc (sizeof (struct GNUNET_CADET_ChannelAppDataMessage)
1842 crm->data_message->header.size = htons (sizeof (struct GNUNET_CADET_ChannelAppDataMessage) + buf_len);
1843 crm->data_message->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CHANNEL_APP_DATA);
1844 ch->mid_send.mid = htonl (ntohl (ch->mid_send.mid) + 1);
1845 crm->data_message->mid = ch->mid_send;
1846 crm->data_message->ctn = ch->ctn;
1847 GNUNET_memcpy (&crm->data_message[1],
1850 GNUNET_CONTAINER_DLL_insert_tail (ch->head_sent,
1853 LOG (GNUNET_ERROR_TYPE_DEBUG,
1854 "Sending message %u from local client to %s with %u bytes\n",
1855 ntohl (crm->data_message->mid.mid),
1858 if (NULL != ch->retry_data_task)
1860 GNUNET_SCHEDULER_cancel (ch->retry_data_task);
1861 ch->retry_data_task = NULL;
1863 crm->qe = GCT_send (ch->t,
1864 &crm->data_message->header,
1867 GNUNET_assert (NULL == ch->retry_data_task);
1873 * Handle ACK from client on local channel. Means the client is ready
1874 * for more data, see if we have any for it.
1876 * @param ch channel to destroy
1877 * @param client_ccn ccn of the client sending the ack
1880 GCCH_handle_local_ack (struct CadetChannel *ch,
1881 struct GNUNET_CADET_ClientChannelNumber client_ccn)
1883 struct CadetChannelClient *ccc;
1884 struct CadetOutOfOrderMessage *com;
1886 if ( (NULL != ch->owner) &&
1887 (ch->owner->ccn.channel_of_client == client_ccn.channel_of_client) )
1889 else if ( (NULL != ch->dest) &&
1890 (ch->dest->ccn.channel_of_client == client_ccn.channel_of_client) )
1894 ccc->client_ready = GNUNET_YES;
1895 com = ccc->head_recv;
1898 LOG (GNUNET_ERROR_TYPE_DEBUG,
1899 "Got LOCAL_ACK, %s-%X ready to receive more data, but none pending on %s-%X(%p)!\n",
1901 ntohl (client_ccn.channel_of_client),
1903 ntohl (ccc->ccn.channel_of_client),
1905 return; /* none pending */
1907 if (GNUNET_YES == ch->is_loopback)
1911 /* Messages are always in-order, just send */
1912 GNUNET_CONTAINER_DLL_remove (ccc->head_recv,
1916 GSC_send_to_client (ccc->c,
1918 /* Notify sender that we can receive more */
1919 if (ccc->ccn.channel_of_client ==
1920 ch->owner->ccn.channel_of_client)
1922 to_owner = GNUNET_NO;
1926 GNUNET_assert (ccc->ccn.channel_of_client ==
1927 ch->dest->ccn.channel_of_client);
1928 to_owner = GNUNET_YES;
1930 send_ack_to_client (ch,
1936 if ( (com->mid.mid != ch->mid_recv.mid) &&
1937 (GNUNET_NO == ch->out_of_order) &&
1938 (GNUNET_YES == ch->reliable) )
1940 LOG (GNUNET_ERROR_TYPE_DEBUG,
1941 "Got LOCAL_ACK, %s-%X ready to receive more data (but next one is out-of-order %u vs. %u)!\n",
1943 ntohl (ccc->ccn.channel_of_client),
1944 ntohl (com->mid.mid),
1945 ntohl (ch->mid_recv.mid));
1946 return; /* missing next one in-order */
1949 LOG (GNUNET_ERROR_TYPE_DEBUG,
1950 "Got LOCAL_ACK, giving payload message %u to %s-%X on %s\n",
1951 ntohl (com->mid.mid),
1953 ntohl (ccc->ccn.channel_of_client),
1956 /* all good, pass next message to client */
1957 GNUNET_CONTAINER_DLL_remove (ccc->head_recv,
1961 /* FIXME: if unreliable, this is not aggressive
1962 enough, as it would be OK to have lost some! */
1964 ch->mid_recv.mid = htonl (1 + ntohl (com->mid.mid));
1965 ch->mid_futures >>= 1; /* equivalent to division by 2 */
1966 ccc->client_ready = GNUNET_NO;
1967 GSC_send_to_client (ccc->c,
1970 send_channel_data_ack (ch);
1971 if (NULL != ccc->head_recv)
1973 if (GNUNET_NO == ch->destroy)
1975 GCT_send_channel_destroy (ch->t,
1977 channel_destroy (ch);
1981 #define LOG2(level, ...) GNUNET_log_from_nocheck(level,"cadet-chn",__VA_ARGS__)
1987 * @param ch Channel.
1988 * @param level Debug level to use.
1991 GCCH_debug (struct CadetChannel *ch,
1992 enum GNUNET_ErrorType level)
1996 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
1998 __FILE__, __FUNCTION__, __LINE__);
2004 LOG2 (level, "CHN *** DEBUG NULL CHANNEL ***\n");
2012 if (NULL != ch->owner)
2015 "CHN origin %s ready %s local-id: %u\n",
2016 GSC_2s (ch->owner->c),
2017 ch->owner->client_ready ? "YES" : "NO",
2018 ntohl (ch->owner->ccn.channel_of_client));
2020 if (NULL != ch->dest)
2023 "CHN destination %s ready %s local-id: %u\n",
2024 GSC_2s (ch->dest->c),
2025 ch->dest->client_ready ? "YES" : "NO",
2026 ntohl (ch->dest->ccn.channel_of_client));
2029 "CHN Message IDs recv: %d (%LLX), send: %d\n",
2030 ntohl (ch->mid_recv.mid),
2031 (unsigned long long) ch->mid_futures,
2032 ntohl (ch->mid_send.mid));
2037 /* end of gnunet-service-cadet-new_channel.c */