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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));
664 ch->dest = GNUNET_new (struct CadetChannelClient);
666 ch->dest->client_ready = GNUNET_YES;
673 ch->t = GCP_get_tunnel (destination,
675 ch->retry_time = CADET_INITIAL_RETRANSMIT_TIME;
676 ch->ctn = GCT_add_channel (ch->t,
679 GNUNET_STATISTICS_update (stats,
683 LOG (GNUNET_ERROR_TYPE_DEBUG,
684 "Created channel to port %s at peer %s for %s using %s\n",
686 GCP_2s (destination),
688 (GNUNET_YES == ch->is_loopback) ? "loopback" : GCT_2s (ch->t));
694 * We had an incoming channel to a port that is closed.
695 * It has not been opened for a while, drop it.
697 * @param cls the channel to drop
700 timeout_closed_cb (void *cls)
702 struct CadetChannel *ch = cls;
704 ch->retry_control_task = NULL;
705 LOG (GNUNET_ERROR_TYPE_DEBUG,
706 "Closing incoming channel to port %s from peer %s due to timeout\n",
707 GNUNET_h2s (&ch->port),
708 GCP_2s (GCT_get_destination (ch->t)));
709 channel_destroy (ch);
714 * Create a new channel based on a request coming in over the network.
716 * @param t tunnel to the remote peer
717 * @param ctn identifier of this channel in the tunnel
718 * @param port desired local port
719 * @param options options for the channel
720 * @return handle to the new channel
722 struct CadetChannel *
723 GCCH_channel_incoming_new (struct CadetTunnel *t,
724 struct GNUNET_CADET_ChannelTunnelNumber ctn,
725 const struct GNUNET_HashCode *port,
728 struct CadetChannel *ch;
729 struct CadetClient *c;
731 ch = GNUNET_new (struct CadetChannel);
735 ch->retry_time = CADET_INITIAL_RETRANSMIT_TIME;
736 ch->nobuffer = (0 != (options & GNUNET_CADET_OPTION_NOBUFFER));
737 ch->reliable = (0 != (options & GNUNET_CADET_OPTION_RELIABLE));
738 ch->out_of_order = (0 != (options & GNUNET_CADET_OPTION_OUT_OF_ORDER));
739 ch->max_pending_messages = (ch->nobuffer) ? 1 : 4; /* FIXME: 4!? Do not hardcode! */
740 GNUNET_STATISTICS_update (stats,
745 c = GNUNET_CONTAINER_multihashmap_get (open_ports,
749 /* port closed, wait for it to possibly open */
750 ch->state = CADET_CHANNEL_LOOSE;
751 (void) GNUNET_CONTAINER_multihashmap_put (loose_channels,
754 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
755 ch->retry_control_task
756 = GNUNET_SCHEDULER_add_delayed (TIMEOUT_CLOSED_PORT,
759 LOG (GNUNET_ERROR_TYPE_DEBUG,
760 "Created loose incoming channel to port %s from peer %s\n",
761 GNUNET_h2s (&ch->port),
762 GCP_2s (GCT_get_destination (ch->t)));
769 GNUNET_STATISTICS_update (stats,
778 * Function called once the tunnel confirms that we sent the
779 * ACK message. Just remembers it was sent, we do not expect
782 * @param cls our `struct CadetChannel`.
783 * @param cid identifier of the connection within the tunnel, NULL
784 * if transmission failed
787 send_ack_cb (void *cls,
788 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cid)
790 struct CadetChannel *ch = cls;
792 GNUNET_assert (NULL != ch->last_control_qe);
793 ch->last_control_qe = NULL;
798 * Compute and send the current #GNUNET_MESSAGE_TYPE_CADET_CHANNEL_APP_DATA_ACK to the other peer.
800 * @param ch channel to send the #GNUNET_MESSAGE_TYPE_CADET_CHANNEL_APP_DATA_ACK for
803 send_channel_data_ack (struct CadetChannel *ch)
805 struct GNUNET_CADET_ChannelDataAckMessage msg;
807 if (GNUNET_NO == ch->reliable)
808 return; /* no ACKs */
809 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CHANNEL_APP_DATA_ACK);
810 msg.header.size = htons (sizeof (msg));
812 msg.mid.mid = htonl (ntohl (ch->mid_recv.mid));
813 msg.futures = GNUNET_htonll (ch->mid_futures);
814 LOG (GNUNET_ERROR_TYPE_DEBUG,
815 "Sending DATA_ACK %u:%llX via %s\n",
816 (unsigned int) ntohl (msg.mid.mid),
817 (unsigned long long) ch->mid_futures,
819 if (NULL != ch->last_control_qe)
820 GCT_send_cancel (ch->last_control_qe);
821 ch->last_control_qe = GCT_send (ch->t,
829 * Send our initial #GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN_ACK to the client confirming that the
832 * @param cls the `struct CadetChannel`
835 send_open_ack (void *cls)
837 struct CadetChannel *ch = cls;
838 struct GNUNET_CADET_ChannelManageMessage msg;
840 LOG (GNUNET_ERROR_TYPE_DEBUG,
841 "Sending CHANNEL_OPEN_ACK on %s\n",
843 ch->retry_control_task = NULL;
844 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN_ACK);
845 msg.header.size = htons (sizeof (msg));
846 msg.reserved = htonl (0);
848 if (NULL != ch->last_control_qe)
849 GCT_send_cancel (ch->last_control_qe);
850 ch->last_control_qe = GCT_send (ch->t,
858 * We got a #GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN message again for
859 * this channel. If the binding was successful, (re)transmit the
860 * #GNUNET_MESSAGE_TYPE_CADET_CHANNEL_OPEN_ACK.
862 * @param ch channel that got the duplicate open
863 * @param cti identifier of the connection that delivered the message
866 GCCH_handle_duplicate_open (struct CadetChannel *ch,
867 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti)
869 if (NULL == ch->dest)
871 LOG (GNUNET_ERROR_TYPE_DEBUG,
872 "Ignoring duplicate CHANNEL_OPEN on %s: port is closed\n",
876 if (NULL != ch->retry_control_task)
878 LOG (GNUNET_ERROR_TYPE_DEBUG,
879 "Ignoring duplicate CHANNEL_OPEN on %s: control message is pending\n",
883 LOG (GNUNET_ERROR_TYPE_DEBUG,
884 "Retransmitting CHANNEL_OPEN_ACK on %s\n",
886 ch->retry_control_task
887 = GNUNET_SCHEDULER_add_now (&send_open_ack,
893 * Send a #GNUNET_MESSAGE_TYPE_CADET_LOCAL_ACK to the client to solicit more messages.
895 * @param ch channel the ack is for
896 * @param to_owner #GNUNET_YES to send to owner,
897 * #GNUNET_NO to send to dest
900 send_ack_to_client (struct CadetChannel *ch,
903 struct GNUNET_MQ_Envelope *env;
904 struct GNUNET_CADET_LocalAck *ack;
905 struct CadetChannelClient *ccc;
907 ccc = (GNUNET_YES == to_owner) ? ch->owner : ch->dest;
910 /* This can happen if we are just getting ACKs after
911 our local client already disconnected. */
912 GNUNET_assert (GNUNET_YES == ch->destroy);
915 env = GNUNET_MQ_msg (ack,
916 GNUNET_MESSAGE_TYPE_CADET_LOCAL_ACK);
918 LOG (GNUNET_ERROR_TYPE_DEBUG,
919 "Sending CADET_LOCAL_ACK to %s (%s) at ccn %X (%u/%u pending)\n",
921 (GNUNET_YES == to_owner) ? "owner" : "dest",
922 ntohl (ack->ccn.channel_of_client),
923 ch->pending_messages,
924 ch->max_pending_messages);
925 GSC_send_to_client (ccc->c,
931 * A client is bound to the port that we have a channel
932 * open to. Send the acknowledgement for the connection
933 * request and establish the link with the client.
935 * @param ch open incoming channel
936 * @param c client listening on the respective port
939 GCCH_bind (struct CadetChannel *ch,
940 struct CadetClient *c)
943 struct CadetChannelClient *cccd;
945 LOG (GNUNET_ERROR_TYPE_DEBUG,
946 "Binding %s from %s to port %s of %s\n",
949 GNUNET_h2s (&ch->port),
951 if (NULL != ch->retry_control_task)
953 /* there might be a timeout task here */
954 GNUNET_SCHEDULER_cancel (ch->retry_control_task);
955 ch->retry_control_task = NULL;
959 options |= GNUNET_CADET_OPTION_NOBUFFER;
961 options |= GNUNET_CADET_OPTION_RELIABLE;
962 if (ch->out_of_order)
963 options |= GNUNET_CADET_OPTION_OUT_OF_ORDER;
964 cccd = GNUNET_new (struct CadetChannelClient);
967 cccd->client_ready = GNUNET_YES;
968 cccd->ccn = GSC_bind (c,
970 (GNUNET_YES == ch->is_loopback)
971 ? GCP_get (&my_full_id,
973 : GCT_get_destination (ch->t),
976 GNUNET_assert (ntohl (cccd->ccn.channel_of_client) <
977 GNUNET_CADET_LOCAL_CHANNEL_ID_CLI);
978 ch->mid_recv.mid = htonl (1); /* The OPEN counts as message 0! */
979 if (GNUNET_YES == ch->is_loopback)
981 ch->state = CADET_CHANNEL_OPEN_SENT;
982 GCCH_handle_channel_open_ack (ch,
987 /* notify other peer that we accepted the connection */
988 ch->state = CADET_CHANNEL_READY;
989 ch->retry_control_task
990 = GNUNET_SCHEDULER_add_now (&send_open_ack,
993 /* give client it's initial supply of ACKs */
994 GNUNET_assert (ntohl (cccd->ccn.channel_of_client) <
995 GNUNET_CADET_LOCAL_CHANNEL_ID_CLI);
996 for (unsigned int i=0;i<ch->max_pending_messages;i++)
997 send_ack_to_client (ch,
1003 * Destroy locally created channel. Called by the local client, so no
1004 * need to tell the client.
1006 * @param ch channel to destroy
1007 * @param c client that caused the destruction
1008 * @param ccn client number of the client @a c
1011 GCCH_channel_local_destroy (struct CadetChannel *ch,
1012 struct CadetClient *c,
1013 struct GNUNET_CADET_ClientChannelNumber ccn)
1015 LOG (GNUNET_ERROR_TYPE_DEBUG,
1016 "%s asks for destruction of %s\n",
1019 GNUNET_assert (NULL != c);
1020 if ( (NULL != ch->owner) &&
1021 (c == ch->owner->c) &&
1022 (ccn.channel_of_client == ch->owner->ccn.channel_of_client) )
1024 free_channel_client (ch->owner);
1027 else if ( (NULL != ch->dest) &&
1028 (c == ch->dest->c) &&
1029 (ccn.channel_of_client == ch->dest->ccn.channel_of_client) )
1031 free_channel_client (ch->dest);
1039 if (GNUNET_YES == ch->destroy)
1041 /* other end already destroyed, with the local client gone, no need
1042 to finish transmissions, just destroy immediately. */
1043 channel_destroy (ch);
1046 if ( (NULL != ch->head_sent) ||
1047 (NULL != ch->owner) ||
1048 (NULL != ch->dest) )
1050 /* Wait for other end to destroy us as well,
1051 and otherwise allow send queue to be transmitted first */
1052 ch->destroy = GNUNET_YES;
1055 /* If the we ever sent the CHANNEL_CREATE, we need to send a destroy message. */
1058 case CADET_CHANNEL_NEW:
1061 case CADET_CHANNEL_LOOSE:
1062 GSC_drop_loose_channel (&ch->port,
1066 GCT_send_channel_destroy (ch->t,
1069 /* Nothing left to do, just finish destruction */
1070 channel_destroy (ch);
1075 * We got an acknowledgement for the creation of the channel
1076 * (the port is open on the other side). Begin transmissions.
1078 * @param ch channel to destroy
1079 * @param cti identifier of the connection that delivered the message
1082 GCCH_handle_channel_open_ack (struct CadetChannel *ch,
1083 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti)
1087 case CADET_CHANNEL_NEW:
1088 /* this should be impossible */
1091 case CADET_CHANNEL_LOOSE:
1092 /* This makes no sense. */
1093 GNUNET_break_op (0);
1095 case CADET_CHANNEL_OPEN_SENT:
1096 if (NULL == ch->owner)
1098 /* We're not the owner, wrong direction! */
1099 GNUNET_break_op (0);
1102 LOG (GNUNET_ERROR_TYPE_DEBUG,
1103 "Received CHANNEL_OPEN_ACK for waiting %s, entering READY state\n",
1105 if (NULL != ch->retry_control_task) /* can be NULL if ch->is_loopback */
1107 GNUNET_SCHEDULER_cancel (ch->retry_control_task);
1108 ch->retry_control_task = NULL;
1110 ch->state = CADET_CHANNEL_READY;
1111 /* On first connect, send client as many ACKs as we allow messages
1113 for (unsigned int i=0;i<ch->max_pending_messages;i++)
1114 send_ack_to_client (ch,
1117 case CADET_CHANNEL_READY:
1118 /* duplicate ACK, maybe we retried the CREATE. Ignore. */
1119 LOG (GNUNET_ERROR_TYPE_DEBUG,
1120 "Received duplicate channel OPEN_ACK for %s\n",
1122 GNUNET_STATISTICS_update (stats,
1123 "# duplicate CREATE_ACKs",
1132 * Test if element @a e1 comes before element @a e2.
1134 * @param cls closure, to a flag where we indicate duplicate packets
1135 * @param m1 a message of to sort
1136 * @param m2 another message to sort
1137 * @return #GNUNET_YES if @e1 < @e2, otherwise #GNUNET_NO
1140 is_before (void *cls,
1141 struct CadetOutOfOrderMessage *m1,
1142 struct CadetOutOfOrderMessage *m2)
1144 int *duplicate = cls;
1145 uint32_t v1 = ntohl (m1->mid.mid);
1146 uint32_t v2 = ntohl (m2->mid.mid);
1151 *duplicate = GNUNET_YES;
1152 if (delta > (uint32_t) INT_MAX)
1154 /* in overflow range, we can safely assume we wrapped around */
1159 /* result is small, thus v2 > v1, thus m1 < m2 */
1166 * We got payload data for a channel. Pass it on to the client
1167 * and send an ACK to the other end (once flow control allows it!)
1169 * @param ch channel that got data
1170 * @param cti identifier of the connection that delivered the message
1171 * @param msg message that was received
1174 GCCH_handle_channel_plaintext_data (struct CadetChannel *ch,
1175 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti,
1176 const struct GNUNET_CADET_ChannelAppDataMessage *msg)
1178 struct GNUNET_MQ_Envelope *env;
1179 struct GNUNET_CADET_LocalData *ld;
1180 struct CadetChannelClient *ccc;
1181 size_t payload_size;
1182 struct CadetOutOfOrderMessage *com;
1189 GNUNET_assert (GNUNET_NO == ch->is_loopback);
1190 if ( (GNUNET_YES == ch->destroy) &&
1191 (NULL == ch->owner) &&
1192 (NULL == ch->dest) )
1194 /* This client is gone, but we still have messages to send to
1195 the other end (which is why @a ch is not yet dead). However,
1196 we cannot pass messages to our client anymore. */
1197 LOG (GNUNET_ERROR_TYPE_DEBUG,
1198 "Dropping incoming payload on %s as this end is already closed\n",
1200 /* send back DESTROY notification to stop further retransmissions! */
1201 GCT_send_channel_destroy (ch->t,
1205 payload_size = ntohs (msg->header.size) - sizeof (*msg);
1206 env = GNUNET_MQ_msg_extra (ld,
1208 GNUNET_MESSAGE_TYPE_CADET_LOCAL_DATA);
1209 ld->ccn = (NULL == ch->dest) ? ch->owner->ccn : ch->dest->ccn;
1210 GNUNET_memcpy (&ld[1],
1213 ccc = (NULL != ch->owner) ? ch->owner : ch->dest;
1214 if ( (GNUNET_YES == ccc->client_ready) &&
1215 ( (GNUNET_YES == ch->out_of_order) ||
1216 (msg->mid.mid == ch->mid_recv.mid) ) )
1218 LOG (GNUNET_ERROR_TYPE_DEBUG,
1219 "Giving %u bytes of payload with MID %u from %s to client %s\n",
1220 (unsigned int) payload_size,
1221 ntohl (msg->mid.mid),
1224 ccc->client_ready = GNUNET_NO;
1225 GSC_send_to_client (ccc->c,
1227 ch->mid_recv.mid = htonl (1 + ntohl (ch->mid_recv.mid));
1228 ch->mid_futures >>= 1;
1229 send_channel_data_ack (ch);
1233 if (GNUNET_YES == ch->reliable)
1235 /* check if message ought to be dropped because it is ancient/too distant/duplicate */
1236 mid_min = ntohl (ch->mid_recv.mid);
1237 mid_max = mid_min + ch->max_pending_messages;
1238 mid_msg = ntohl (msg->mid.mid);
1239 if ( ( (uint32_t) (mid_msg - mid_min) > ch->max_pending_messages) ||
1240 ( (uint32_t) (mid_max - mid_msg) > ch->max_pending_messages) )
1242 LOG (GNUNET_ERROR_TYPE_DEBUG,
1243 "%s at %u drops ancient or far-future message %u\n",
1245 (unsigned int) mid_min,
1246 ntohl (msg->mid.mid));
1248 GNUNET_STATISTICS_update (stats,
1249 "# duplicate DATA (ancient or future)",
1252 GNUNET_MQ_discard (env);
1253 send_channel_data_ack (ch);
1256 /* mark bit for future ACKs */
1257 delta = mid_msg - mid_min - 1; /* overflow/underflow are OK here */
1260 if (0 != (ch->mid_futures & (1LLU << delta)))
1262 /* Duplicate within the queue, drop also */
1263 LOG (GNUNET_ERROR_TYPE_DEBUG,
1264 "Duplicate payload of %u bytes on %s (mid %u) dropped\n",
1265 (unsigned int) payload_size,
1267 ntohl (msg->mid.mid));
1268 GNUNET_STATISTICS_update (stats,
1272 GNUNET_MQ_discard (env);
1273 send_channel_data_ack (ch);
1276 ch->mid_futures |= (1LLU << delta);
1277 LOG (GNUNET_ERROR_TYPE_DEBUG,
1278 "Marked bit %llX for mid %u (base: %u); now: %llX\n",
1285 else /* ! ch->reliable */
1287 /* Channel is unreliable, so we do not ACK. But we also cannot
1288 allow buffering everything, so check if we have space... */
1289 if (ccc->num_recv >= ch->max_pending_messages)
1291 struct CadetOutOfOrderMessage *drop;
1293 /* Yep, need to drop. Drop the oldest message in
1295 LOG (GNUNET_ERROR_TYPE_DEBUG,
1296 "Queue full due slow client on %s, dropping oldest message\n",
1298 GNUNET_STATISTICS_update (stats,
1299 "# messages dropped due to slow client",
1302 drop = ccc->head_recv;
1303 GNUNET_CONTAINER_DLL_remove (ccc->head_recv,
1307 GNUNET_MQ_discard (drop->env);
1312 /* Insert message into sorted out-of-order queue */
1313 com = GNUNET_new (struct CadetOutOfOrderMessage);
1314 com->mid = msg->mid;
1316 duplicate = GNUNET_NO;
1317 GNUNET_CONTAINER_DLL_insert_sorted (struct CadetOutOfOrderMessage,
1324 if (GNUNET_YES == duplicate)
1326 /* Duplicate within the queue, drop also (this is not covered by
1327 the case above if "delta" >= 64, which could be the case if
1328 max_pending_messages is also >= 64 or if our client is unready
1329 and we are seeing retransmissions of the message our client is
1331 LOG (GNUNET_ERROR_TYPE_DEBUG,
1332 "Duplicate payload of %u bytes on %s (mid %u) dropped\n",
1333 (unsigned int) payload_size,
1335 ntohl (msg->mid.mid));
1336 GNUNET_STATISTICS_update (stats,
1340 GNUNET_CONTAINER_DLL_remove (ccc->head_recv,
1344 GNUNET_MQ_discard (com->env);
1346 send_channel_data_ack (ch);
1349 LOG (GNUNET_ERROR_TYPE_DEBUG,
1350 "Queued %s payload of %u bytes on %s-%X(%p) (mid %u, need %u first)\n",
1351 (GNUNET_YES == ccc->client_ready)
1353 : "client-not-ready",
1354 (unsigned int) payload_size,
1356 ntohl (ccc->ccn.channel_of_client),
1358 ntohl (msg->mid.mid),
1359 ntohl (ch->mid_recv.mid));
1360 /* NOTE: this ACK we _could_ skip, as the packet is out-of-order and
1361 the sender may already be transmitting the previous one. Needs
1362 experimental evaluation to see if/when this ACK helps or
1363 hurts. (We might even want another option.) */
1364 send_channel_data_ack (ch);
1369 * Function called once the tunnel has sent one of our messages.
1370 * If the message is unreliable, simply frees the `crm`. If the
1371 * message was reliable, calculate retransmission time and
1372 * wait for ACK (or retransmit).
1374 * @param cls the `struct CadetReliableMessage` that was sent
1375 * @param cid identifier of the connection within the tunnel, NULL
1376 * if transmission failed
1379 data_sent_cb (void *cls,
1380 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cid);
1384 * We need to retry a transmission, the last one took too long to
1387 * @param cls the `struct CadetChannel` where we need to retransmit
1390 retry_transmission (void *cls)
1392 struct CadetChannel *ch = cls;
1393 struct CadetReliableMessage *crm = ch->head_sent;
1395 ch->retry_data_task = NULL;
1396 GNUNET_assert (NULL == crm->qe);
1397 LOG (GNUNET_ERROR_TYPE_DEBUG,
1398 "Retrying transmission on %s of message %u\n",
1400 (unsigned int) ntohl (crm->data_message->mid.mid));
1401 crm->qe = GCT_send (ch->t,
1402 &crm->data_message->header,
1405 GNUNET_assert (NULL == ch->retry_data_task);
1410 * We got an PLAINTEXT_DATA_ACK for a message in our queue, remove it from
1411 * the queue and tell our client that it can send more.
1413 * @param ch the channel that got the PLAINTEXT_DATA_ACK
1414 * @param cti identifier of the connection that delivered the message
1415 * @param crm the message that got acknowledged
1418 handle_matching_ack (struct CadetChannel *ch,
1419 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti,
1420 struct CadetReliableMessage *crm)
1422 GNUNET_CONTAINER_DLL_remove (ch->head_sent,
1425 ch->pending_messages--;
1426 GNUNET_assert (ch->pending_messages < ch->max_pending_messages);
1427 LOG (GNUNET_ERROR_TYPE_DEBUG,
1428 "Received DATA_ACK on %s for message %u (%u ACKs pending)\n",
1430 (unsigned int) ntohl (crm->data_message->mid.mid),
1431 ch->pending_messages);
1432 if (NULL != crm->qe)
1434 GCT_send_cancel (crm->qe);
1437 if ( (1 == crm->num_transmissions) &&
1440 GCC_ack_observed (cti);
1441 if (0 == memcmp (cti,
1442 &crm->connection_taken,
1443 sizeof (struct GNUNET_CADET_ConnectionTunnelIdentifier)))
1445 GCC_latency_observed (cti,
1446 GNUNET_TIME_absolute_get_duration (crm->first_transmission_time));
1449 GNUNET_free (crm->data_message);
1451 send_ack_to_client (ch,
1459 * We got an acknowledgement for payload data for a channel.
1460 * Possibly resume transmissions.
1462 * @param ch channel that got the ack
1463 * @param cti identifier of the connection that delivered the message
1464 * @param ack details about what was received
1467 GCCH_handle_channel_plaintext_data_ack (struct CadetChannel *ch,
1468 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti,
1469 const struct GNUNET_CADET_ChannelDataAckMessage *ack)
1471 struct CadetReliableMessage *crm;
1472 struct CadetReliableMessage *crmn;
1478 GNUNET_break (GNUNET_NO == ch->is_loopback);
1479 if (GNUNET_NO == ch->reliable)
1481 /* not expecting ACKs on unreliable channel, odd */
1482 GNUNET_break_op (0);
1485 /* mid_base is the MID of the next message that the
1486 other peer expects (i.e. that is missing!), everything
1487 LOWER (but excluding mid_base itself) was received. */
1488 mid_base = ntohl (ack->mid.mid);
1489 mid_mask = GNUNET_htonll (ack->futures);
1491 for (crm = ch->head_sent;
1496 delta = (unsigned int) (ntohl (crm->data_message->mid.mid) - mid_base);
1497 if (delta >= UINT_MAX - ch->max_pending_messages)
1499 /* overflow, means crm was a bit in the past, so this ACK counts for it. */
1500 LOG (GNUNET_ERROR_TYPE_DEBUG,
1501 "Got DATA_ACK with base %u satisfying past message %u on %s\n",
1502 (unsigned int) mid_base,
1503 ntohl (crm->data_message->mid.mid),
1505 handle_matching_ack (ch,
1514 LOG (GNUNET_ERROR_TYPE_DEBUG,
1515 "Testing bit %llX for mid %u (base: %u)\n",
1517 ntohl (crm->data_message->mid.mid),
1519 if (0 != (mid_mask & (1LLU << delta)))
1521 LOG (GNUNET_ERROR_TYPE_DEBUG,
1522 "Got DATA_ACK with mask for %u on %s\n",
1523 ntohl (crm->data_message->mid.mid),
1525 handle_matching_ack (ch,
1531 if (GNUNET_NO == found)
1533 /* ACK for message we already dropped, might have been a
1534 duplicate ACK? Ignore. */
1535 LOG (GNUNET_ERROR_TYPE_DEBUG,
1536 "Duplicate DATA_ACK on %s, ignoring\n",
1538 GNUNET_STATISTICS_update (stats,
1539 "# duplicate DATA_ACKs",
1544 if (NULL != ch->retry_data_task)
1546 GNUNET_SCHEDULER_cancel (ch->retry_data_task);
1547 ch->retry_data_task = NULL;
1549 if ( (NULL != ch->head_sent) &&
1550 (NULL == ch->head_sent->qe) )
1552 = GNUNET_SCHEDULER_add_at (ch->head_sent->next_retry,
1553 &retry_transmission,
1559 * Destroy channel, based on the other peer closing the
1560 * connection. Also needs to remove this channel from
1563 * @param ch channel to destroy
1564 * @param cti identifier of the connection that delivered the message,
1565 * NULL if we are simulating receiving a destroy due to shutdown
1568 GCCH_handle_remote_destroy (struct CadetChannel *ch,
1569 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cti)
1571 struct CadetChannelClient *ccc;
1573 GNUNET_assert (GNUNET_NO == ch->is_loopback);
1574 LOG (GNUNET_ERROR_TYPE_DEBUG,
1575 "Received remote channel DESTROY for %s\n",
1577 if (GNUNET_YES == ch->destroy)
1579 /* Local client already gone, this is instant-death. */
1580 channel_destroy (ch);
1583 ccc = (NULL != ch->owner) ? ch->owner : ch->dest;
1584 if (NULL != ccc->head_recv)
1586 LOG (GNUNET_ERROR_TYPE_WARNING,
1587 "Lost end of transmission due to remote shutdown on %s\n",
1589 /* FIXME: change API to notify client about truncated transmission! */
1591 ch->destroy = GNUNET_YES;
1592 GSC_handle_remote_channel_destroy (ccc->c,
1595 channel_destroy (ch);
1600 * Test if element @a e1 comes before element @a e2.
1602 * @param cls closure, to a flag where we indicate duplicate packets
1603 * @param crm1 an element of to sort
1604 * @param crm2 another element to sort
1605 * @return #GNUNET_YES if @e1 < @e2, otherwise #GNUNET_NO
1608 cmp_crm_by_next_retry (void *cls,
1609 struct CadetReliableMessage *crm1,
1610 struct CadetReliableMessage *crm2)
1612 if (crm1->next_retry.abs_value_us <
1613 crm2->next_retry.abs_value_us)
1620 * Function called once the tunnel has sent one of our messages.
1621 * If the message is unreliable, simply frees the `crm`. If the
1622 * message was reliable, calculate retransmission time and
1623 * wait for ACK (or retransmit).
1625 * @param cls the `struct CadetReliableMessage` that was sent
1626 * @param cid identifier of the connection within the tunnel, NULL
1627 * if transmission failed
1630 data_sent_cb (void *cls,
1631 const struct GNUNET_CADET_ConnectionTunnelIdentifier *cid)
1633 struct CadetReliableMessage *crm = cls;
1634 struct CadetChannel *ch = crm->ch;
1636 GNUNET_assert (GNUNET_NO == ch->is_loopback);
1637 GNUNET_assert (NULL != crm->qe);
1639 GNUNET_CONTAINER_DLL_remove (ch->head_sent,
1642 if (GNUNET_NO == ch->reliable)
1644 GNUNET_free (crm->data_message);
1646 ch->pending_messages--;
1647 send_ack_to_client (ch,
1655 /* There was an error sending. */
1656 crm->num_transmissions = GNUNET_SYSERR;
1658 else if (GNUNET_SYSERR != crm->num_transmissions)
1660 /* Increment transmission counter, and possibly store @a cid
1661 if this was the first transmission. */
1662 crm->num_transmissions++;
1663 if (1 == crm->num_transmissions)
1665 crm->first_transmission_time = GNUNET_TIME_absolute_get ();
1666 crm->connection_taken = *cid;
1667 GCC_ack_expected (cid);
1670 if ( (0 == crm->retry_delay.rel_value_us) &&
1673 struct CadetConnection *cc = GCC_lookup (cid);
1676 crm->retry_delay = GCC_get_metrics (cc)->aged_latency;
1678 crm->retry_delay = ch->retry_time;
1680 crm->retry_delay = GNUNET_TIME_STD_BACKOFF (crm->retry_delay);
1681 crm->retry_delay = GNUNET_TIME_relative_max (crm->retry_delay,
1683 crm->next_retry = GNUNET_TIME_relative_to_absolute (crm->retry_delay);
1685 GNUNET_CONTAINER_DLL_insert_sorted (struct CadetReliableMessage,
1686 cmp_crm_by_next_retry,
1691 LOG (GNUNET_ERROR_TYPE_DEBUG,
1692 "Message %u sent, next transmission on %s in %s\n",
1693 (unsigned int) ntohl (crm->data_message->mid.mid),
1695 GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_remaining (ch->head_sent->next_retry),
1697 if (NULL == ch->head_sent->qe)
1699 if (NULL != ch->retry_data_task)
1700 GNUNET_SCHEDULER_cancel (ch->retry_data_task);
1702 = GNUNET_SCHEDULER_add_at (ch->head_sent->next_retry,
1703 &retry_transmission,
1710 * Handle data given by a client.
1712 * Check whether the client is allowed to send in this tunnel, save if
1713 * channel is reliable and send an ACK to the client if there is still
1714 * buffer space in the tunnel.
1716 * @param ch Channel.
1717 * @param sender_ccn ccn of the sender
1718 * @param buf payload to transmit.
1719 * @param buf_len number of bytes in @a buf
1720 * @return #GNUNET_OK if everything goes well,
1721 * #GNUNET_SYSERR in case of an error.
1724 GCCH_handle_local_data (struct CadetChannel *ch,
1725 struct GNUNET_CADET_ClientChannelNumber sender_ccn,
1729 struct CadetReliableMessage *crm;
1731 if (ch->pending_messages > ch->max_pending_messages)
1734 return GNUNET_SYSERR;
1736 if (GNUNET_YES == ch->destroy)
1738 /* we are going down, drop messages */
1741 ch->pending_messages++;
1743 if (GNUNET_YES == ch->is_loopback)
1745 struct CadetChannelClient *receiver;
1746 struct GNUNET_MQ_Envelope *env;
1747 struct GNUNET_CADET_LocalData *ld;
1750 env = GNUNET_MQ_msg_extra (ld,
1752 GNUNET_MESSAGE_TYPE_CADET_LOCAL_DATA);
1753 if ( (NULL != ch->owner) &&
1754 (sender_ccn.channel_of_client ==
1755 ch->owner->ccn.channel_of_client) )
1757 receiver = ch->dest;
1758 to_owner = GNUNET_NO;
1760 else if ( (NULL != ch->dest) &&
1761 (sender_ccn.channel_of_client ==
1762 ch->dest->ccn.channel_of_client) )
1764 receiver = ch->owner;
1765 to_owner = GNUNET_YES;
1770 return GNUNET_SYSERR;
1772 ld->ccn = receiver->ccn;
1773 GNUNET_memcpy (&ld[1],
1776 if (GNUNET_YES == receiver->client_ready)
1778 GSC_send_to_client (receiver->c,
1780 send_ack_to_client (ch,
1785 struct CadetOutOfOrderMessage *oom;
1787 oom = GNUNET_new (struct CadetOutOfOrderMessage);
1789 GNUNET_CONTAINER_DLL_insert_tail (receiver->head_recv,
1790 receiver->tail_recv,
1792 receiver->num_recv++;
1797 /* Everything is correct, send the message. */
1798 crm = GNUNET_malloc (sizeof (*crm));
1800 crm->data_message = GNUNET_malloc (sizeof (struct GNUNET_CADET_ChannelAppDataMessage)
1802 crm->data_message->header.size = htons (sizeof (struct GNUNET_CADET_ChannelAppDataMessage) + buf_len);
1803 crm->data_message->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CHANNEL_APP_DATA);
1804 ch->mid_send.mid = htonl (ntohl (ch->mid_send.mid) + 1);
1805 crm->data_message->mid = ch->mid_send;
1806 crm->data_message->ctn = ch->ctn;
1807 GNUNET_memcpy (&crm->data_message[1],
1810 GNUNET_CONTAINER_DLL_insert_tail (ch->head_sent,
1813 LOG (GNUNET_ERROR_TYPE_DEBUG,
1814 "Sending message %u from local client to %s with %u bytes\n",
1815 ntohl (crm->data_message->mid.mid),
1818 if (NULL != ch->retry_data_task)
1820 GNUNET_SCHEDULER_cancel (ch->retry_data_task);
1821 ch->retry_data_task = NULL;
1823 crm->qe = GCT_send (ch->t,
1824 &crm->data_message->header,
1827 GNUNET_assert (NULL == ch->retry_data_task);
1833 * Handle ACK from client on local channel. Means the client is ready
1834 * for more data, see if we have any for it.
1836 * @param ch channel to destroy
1837 * @param client_ccn ccn of the client sending the ack
1840 GCCH_handle_local_ack (struct CadetChannel *ch,
1841 struct GNUNET_CADET_ClientChannelNumber client_ccn)
1843 struct CadetChannelClient *ccc;
1844 struct CadetOutOfOrderMessage *com;
1846 if ( (NULL != ch->owner) &&
1847 (ch->owner->ccn.channel_of_client == client_ccn.channel_of_client) )
1849 else if ( (NULL != ch->dest) &&
1850 (ch->dest->ccn.channel_of_client == client_ccn.channel_of_client) )
1854 ccc->client_ready = GNUNET_YES;
1855 com = ccc->head_recv;
1858 LOG (GNUNET_ERROR_TYPE_DEBUG,
1859 "Got LOCAL_ACK, %s-%X ready to receive more data, but none pending on %s-%X(%p)!\n",
1861 ntohl (client_ccn.channel_of_client),
1863 ntohl (ccc->ccn.channel_of_client),
1865 return; /* none pending */
1867 if (GNUNET_YES == ch->is_loopback)
1871 /* Messages are always in-order, just send */
1872 GNUNET_CONTAINER_DLL_remove (ccc->head_recv,
1876 GSC_send_to_client (ccc->c,
1878 /* Notify sender that we can receive more */
1879 if (ccc->ccn.channel_of_client ==
1880 ch->owner->ccn.channel_of_client)
1882 to_owner = GNUNET_NO;
1886 GNUNET_assert (ccc->ccn.channel_of_client ==
1887 ch->dest->ccn.channel_of_client);
1888 to_owner = GNUNET_YES;
1890 send_ack_to_client (ch,
1896 if ( (com->mid.mid != ch->mid_recv.mid) &&
1897 (GNUNET_NO == ch->out_of_order) &&
1898 (GNUNET_YES == ch->reliable) )
1900 LOG (GNUNET_ERROR_TYPE_DEBUG,
1901 "Got LOCAL_ACK, %s-%X ready to receive more data (but next one is out-of-order %u vs. %u)!\n",
1903 ntohl (ccc->ccn.channel_of_client),
1904 ntohl (com->mid.mid),
1905 ntohl (ch->mid_recv.mid));
1906 return; /* missing next one in-order */
1909 LOG (GNUNET_ERROR_TYPE_DEBUG,
1910 "Got LOCAL_ACK, giving payload message %u to %s-%X on %s\n",
1911 ntohl (com->mid.mid),
1913 ntohl (ccc->ccn.channel_of_client),
1916 /* all good, pass next message to client */
1917 GNUNET_CONTAINER_DLL_remove (ccc->head_recv,
1921 /* FIXME: if unreliable, this is not aggressive
1922 enough, as it would be OK to have lost some! */
1924 ch->mid_recv.mid = htonl (1 + ntohl (com->mid.mid));
1925 ch->mid_futures >>= 1; /* equivalent to division by 2 */
1926 ccc->client_ready = GNUNET_NO;
1927 GSC_send_to_client (ccc->c,
1930 send_channel_data_ack (ch);
1931 if (NULL != ccc->head_recv)
1933 if (GNUNET_NO == ch->destroy)
1935 GCT_send_channel_destroy (ch->t,
1937 channel_destroy (ch);
1941 #define LOG2(level, ...) GNUNET_log_from_nocheck(level,"cadet-chn",__VA_ARGS__)
1947 * @param ch Channel.
1948 * @param level Debug level to use.
1951 GCCH_debug (struct CadetChannel *ch,
1952 enum GNUNET_ErrorType level)
1956 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
1958 __FILE__, __FUNCTION__, __LINE__);
1964 LOG2 (level, "CHN *** DEBUG NULL CHANNEL ***\n");
1972 if (NULL != ch->owner)
1975 "CHN origin %s ready %s local-id: %u\n",
1976 GSC_2s (ch->owner->c),
1977 ch->owner->client_ready ? "YES" : "NO",
1978 ntohl (ch->owner->ccn.channel_of_client));
1980 if (NULL != ch->dest)
1983 "CHN destination %s ready %s local-id: %u\n",
1984 GSC_2s (ch->dest->c),
1985 ch->dest->client_ready ? "YES" : "NO",
1986 ntohl (ch->dest->ccn.channel_of_client));
1989 "CHN Message IDs recv: %d (%LLX), send: %d\n",
1990 ntohl (ch->mid_recv.mid),
1991 (unsigned long long) ch->mid_futures,
1992 ntohl (ch->mid_send.mid));
1997 /* end of gnunet-service-cadet-new_channel.c */