2 This file is part of GNUnet.
3 (C) 2009, 2010, 2011 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file transport/transport_api.c
23 * @brief library to access the low-level P2P IO service
24 * @author Christian Grothoff
27 * - adjust testcases to use new 'try connect' style (should be easy, breaks API compatibility!)
28 * - adjust core service to use new 'try connect' style (should be MUCH nicer there as well!)
32 #include "gnunet_constants.h"
33 #include "gnunet_bandwidth_lib.h"
34 #include "gnunet_client_lib.h"
35 #include "gnunet_constants.h"
36 #include "gnunet_container_lib.h"
37 #include "gnunet_arm_service.h"
38 #include "gnunet_hello_lib.h"
39 #include "gnunet_protocols.h"
40 #include "gnunet_server_lib.h"
41 #include "gnunet_time_lib.h"
42 #include "gnunet_transport_service.h"
43 #include "transport.h"
45 #define LOG(kind,...) GNUNET_log_from (kind, "transport-api",__VA_ARGS__)
48 * How large to start with for the hashmap of neighbours.
50 #define STARTING_NEIGHBOURS_SIZE 16
53 * Handle for a message that should be transmitted to the service.
54 * Used for both control messages and normal messages.
56 struct GNUNET_TRANSPORT_TransmitHandle
60 * We keep all requests in a DLL.
62 struct GNUNET_TRANSPORT_TransmitHandle *next;
65 * We keep all requests in a DLL.
67 struct GNUNET_TRANSPORT_TransmitHandle *prev;
70 * Neighbour for this handle, NULL for control messages.
72 struct Neighbour *neighbour;
75 * Function to call when notify_size bytes are available
78 GNUNET_CONNECTION_TransmitReadyNotify notify;
86 * Timeout for this request, 0 for control messages.
88 struct GNUNET_TIME_Absolute timeout;
91 * Task to trigger request timeout if the request is stalled due to
94 GNUNET_SCHEDULER_TaskIdentifier timeout_task;
97 * How many bytes is our notify callback waiting for?
102 * How important is this message? Not used for control messages.
110 * Entry in hash table of all of our current neighbours.
115 * Overall transport handle.
117 struct GNUNET_TRANSPORT_Handle *h;
120 * Active transmit handle or NULL.
122 struct GNUNET_TRANSPORT_TransmitHandle *th;
125 * Identity of this neighbour.
127 struct GNUNET_PeerIdentity id;
130 * Outbound bandwidh tracker.
132 struct GNUNET_BANDWIDTH_Tracker out_tracker;
135 * Entry in our readyness heap (which is sorted by 'next_ready'
136 * value). NULL if there is no pending transmission request for
137 * this neighbour or if we're waiting for 'is_ready' to become
138 * true AFTER the 'out_tracker' suggested that this peer's quota
139 * has been satisfied (so once 'is_ready' goes to GNUNET_YES,
140 * we should immediately go back into the heap).
142 struct GNUNET_CONTAINER_HeapNode *hn;
145 * Is this peer currently ready to receive a message?
150 * Sending consumed more bytes on wire than payload was announced
151 * This overhead is added to the delay of next sending operation
153 size_t traffic_overhead;
158 * Linked list of functions to call whenever our HELLO is updated.
160 struct GNUNET_TRANSPORT_GetHelloHandle
164 * This is a doubly linked list.
166 struct GNUNET_TRANSPORT_GetHelloHandle *next;
169 * This is a doubly linked list.
171 struct GNUNET_TRANSPORT_GetHelloHandle *prev;
176 struct GNUNET_TRANSPORT_Handle *handle;
179 * Callback to call once we got our HELLO.
181 GNUNET_TRANSPORT_HelloUpdateCallback rec;
192 * Handle for the transport service (includes all of the
193 * state for the transport service).
195 struct GNUNET_TRANSPORT_Handle
199 * Closure for the callbacks.
204 * Function to call for received data.
206 GNUNET_TRANSPORT_ReceiveCallback rec;
209 * function to call on connect events
211 GNUNET_TRANSPORT_NotifyConnect nc_cb;
214 * function to call on disconnect events
216 GNUNET_TRANSPORT_NotifyDisconnect nd_cb;
219 * Head of DLL of control messages.
221 struct GNUNET_TRANSPORT_TransmitHandle *control_head;
224 * Tail of DLL of control messages.
226 struct GNUNET_TRANSPORT_TransmitHandle *control_tail;
229 * The current HELLO message for this peer. Updated
230 * whenever transports change their addresses.
232 struct GNUNET_HELLO_Message *my_hello;
235 * My client connection to the transport service.
237 struct GNUNET_CLIENT_Connection *client;
240 * Handle to our registration with the client for notification.
242 struct GNUNET_CLIENT_TransmitHandle *cth;
245 * Linked list of pending requests for our HELLO.
247 struct GNUNET_TRANSPORT_GetHelloHandle *hwl_head;
250 * Linked list of pending requests for our HELLO.
252 struct GNUNET_TRANSPORT_GetHelloHandle *hwl_tail;
257 const struct GNUNET_CONFIGURATION_Handle *cfg;
260 * Hash map of the current connected neighbours of this peer.
261 * Maps peer identities to 'struct Neighbour' entries.
263 struct GNUNET_CONTAINER_MultiHashMap *neighbours;
266 * Heap sorting peers with pending messages by the timestamps that
267 * specify when we could next send a message to the respective peer.
268 * Excludes control messages (which can always go out immediately).
269 * Maps time stamps to 'struct Neighbour' entries.
271 struct GNUNET_CONTAINER_Heap *ready_heap;
274 * Peer identity as assumed by this process, or all zeros.
276 struct GNUNET_PeerIdentity self;
279 * ID of the task trying to reconnect to the service.
281 GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
284 * ID of the task trying to trigger transmission for a peer while
285 * maintaining bandwidth quotas. In use if there are no control
286 * messages and the smallest entry in the 'ready_heap' has a time
287 * stamp in the future.
289 GNUNET_SCHEDULER_TaskIdentifier quota_task;
292 * Delay until we try to reconnect.
294 struct GNUNET_TIME_Relative reconnect_delay;
297 * Should we check that 'self' matches what the service thinks?
298 * (if GNUNET_NO, then 'self' is all zeros!).
303 * Reconnect in progress
310 * Schedule the task to send one message, either from the control
311 * list or the peer message queues to the service.
313 * @param h transport service to schedule a transmission for
316 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h);
320 * Function that will schedule the job that will try
321 * to connect us again to the client.
323 * @param h transport service to reconnect
326 disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h);
330 * Get the neighbour list entry for the given peer
332 * @param h our context
333 * @param peer peer to look up
334 * @return NULL if no such peer entry exists
336 static struct Neighbour *
337 neighbour_find (struct GNUNET_TRANSPORT_Handle *h,
338 const struct GNUNET_PeerIdentity *peer)
340 return GNUNET_CONTAINER_multihashmap_get (h->neighbours, &peer->hashPubKey);
345 * Add neighbour to our list
347 * @return NULL if this API is currently disconnecting from the service
349 static struct Neighbour *
350 neighbour_add (struct GNUNET_TRANSPORT_Handle *h,
351 const struct GNUNET_PeerIdentity *pid)
355 LOG (GNUNET_ERROR_TYPE_DEBUG, "Creating entry for neighbour `%4s'.\n",
357 n = GNUNET_malloc (sizeof (struct Neighbour));
360 n->is_ready = GNUNET_YES;
361 n->traffic_overhead = 0;
362 GNUNET_BANDWIDTH_tracker_init (&n->out_tracker,
363 GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
364 MAX_BANDWIDTH_CARRY_S);
365 GNUNET_assert (GNUNET_OK ==
366 GNUNET_CONTAINER_multihashmap_put (h->neighbours,
367 &n->id.hashPubKey, n,
368 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
374 * Iterator over hash map entries, for deleting state of a neighbour.
376 * @param cls the 'struct GNUNET_TRANSPORT_Handle*'
377 * @param key peer identity
378 * @param value value in the hash map, the neighbour entry to delete
379 * @return GNUNET_YES if we should continue to
384 neighbour_delete (void *cls, const struct GNUNET_HashCode * key, void *value)
386 struct GNUNET_TRANSPORT_Handle *handle = cls;
387 struct Neighbour *n = value;
389 if (NULL != handle->nd_cb)
390 handle->nd_cb (handle->cls, &n->id);
391 GNUNET_assert (NULL == n->th);
392 GNUNET_assert (NULL == n->hn);
393 GNUNET_assert (GNUNET_YES ==
394 GNUNET_CONTAINER_multihashmap_remove (handle->neighbours, key,
402 * Function we use for handling incoming messages.
404 * @param cls closure (struct GNUNET_TRANSPORT_Handle *)
405 * @param msg message received, NULL on timeout or fatal error
408 demultiplexer (void *cls, const struct GNUNET_MessageHeader *msg)
410 struct GNUNET_TRANSPORT_Handle *h = cls;
411 const struct DisconnectInfoMessage *dim;
412 const struct ConnectInfoMessage *cim;
413 const struct InboundMessage *im;
414 const struct GNUNET_MessageHeader *imm;
415 const struct SendOkMessage *okm;
416 const struct QuotaSetMessage *qm;
417 const struct GNUNET_ATS_Information *ats;
418 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
419 struct GNUNET_TRANSPORT_GetHelloHandle *next_hwl;
421 struct GNUNET_PeerIdentity me;
425 uint32_t bytes_physical;
427 GNUNET_assert (h->client != NULL);
430 LOG (GNUNET_ERROR_TYPE_DEBUG,
431 "Error receiving from transport service, disconnecting temporarily.\n");
432 disconnect_and_schedule_reconnect (h);
435 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
436 GNUNET_TIME_UNIT_FOREVER_REL);
437 size = ntohs (msg->size);
438 switch (ntohs (msg->type))
440 case GNUNET_MESSAGE_TYPE_HELLO:
442 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg, &me))
447 LOG (GNUNET_ERROR_TYPE_DEBUG,
448 "Receiving (my own) `%s' message, I am `%4s'.\n", "HELLO",
450 GNUNET_free_non_null (h->my_hello);
452 if (size < sizeof (struct GNUNET_MessageHeader))
457 h->my_hello = GNUNET_malloc (size);
458 memcpy (h->my_hello, msg, size);
462 next_hwl = hwl->next;
463 hwl->rec (hwl->rec_cls,
464 (const struct GNUNET_MessageHeader *) h->my_hello);
468 case GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT:
469 if (size < sizeof (struct ConnectInfoMessage))
474 cim = (const struct ConnectInfoMessage *) msg;
475 ats_count = ntohl (cim->ats_count);
477 sizeof (struct ConnectInfoMessage) +
478 ats_count * sizeof (struct GNUNET_ATS_Information))
483 ats = (const struct GNUNET_ATS_Information *) &cim[1];
484 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n",
485 "CONNECT", GNUNET_i2s (&cim->id));
486 n = neighbour_find (h, &cim->id);
492 n = neighbour_add (h, &cim->id);
493 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s' with quota %u\n",
494 "CONNECT", GNUNET_i2s (&cim->id), ntohl (cim->quota_out.value__));
495 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, cim->quota_out);
496 if (h->nc_cb != NULL)
497 h->nc_cb (h->cls, &n->id, ats, ats_count);
499 case GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT:
500 if (size != sizeof (struct DisconnectInfoMessage))
505 dim = (const struct DisconnectInfoMessage *) msg;
506 GNUNET_break (ntohl (dim->reserved) == 0);
507 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n",
508 "DISCONNECT", GNUNET_i2s (&dim->peer));
509 n = neighbour_find (h, &dim->peer);
515 neighbour_delete (h, &dim->peer.hashPubKey, n);
517 case GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK:
518 if (size != sizeof (struct SendOkMessage))
523 okm = (const struct SendOkMessage *) msg;
524 bytes_msg = ntohl (okm->bytes_msg);
525 bytes_physical = ntohl (okm->bytes_physical);
526 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message, transmission %s.\n",
527 "SEND_OK", ntohl (okm->success) == GNUNET_OK ? "succeeded" : "failed");
529 n = neighbour_find (h, &okm->peer);
533 if (bytes_physical >= bytes_msg)
535 LOG (GNUNET_ERROR_TYPE_DEBUG, "Overhead for %u byte message: %u \n",
536 bytes_msg, bytes_physical - bytes_msg);
537 n->traffic_overhead += bytes_physical - bytes_msg;
539 GNUNET_break (GNUNET_NO == n->is_ready);
540 n->is_ready = GNUNET_YES;
541 if ((n->th != NULL) && (n->hn == NULL))
543 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != n->th->timeout_task);
544 GNUNET_SCHEDULER_cancel (n->th->timeout_task);
545 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
546 /* we've been waiting for this (congestion, not quota,
547 * caused delayed transmission) */
548 n->hn = GNUNET_CONTAINER_heap_insert (h->ready_heap, n, 0);
549 schedule_transmission (h);
552 case GNUNET_MESSAGE_TYPE_TRANSPORT_RECV:
553 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message.\n", "RECV");
555 sizeof (struct InboundMessage) + sizeof (struct GNUNET_MessageHeader))
560 im = (const struct InboundMessage *) msg;
561 ats_count = ntohl (im->ats_count);
562 ats = (const struct GNUNET_ATS_Information *) &im[1];
563 imm = (const struct GNUNET_MessageHeader *) &ats[ats_count];
564 if (ntohs (imm->size) + sizeof (struct InboundMessage) +
565 ats_count * sizeof (struct GNUNET_ATS_Information) != size)
570 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received message of type %u from `%4s'.\n",
571 ntohs (imm->type), GNUNET_i2s (&im->peer));
572 n = neighbour_find (h, &im->peer);
579 h->rec (h->cls, &im->peer, imm, ats, ats_count);
581 case GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA:
582 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message.\n", "SET_QUOTA");
583 if (size != sizeof (struct QuotaSetMessage))
588 qm = (const struct QuotaSetMessage *) msg;
589 n = neighbour_find (h, &qm->peer);
592 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s' with quota %u\n",
593 "SET_QUOTA", GNUNET_i2s (&qm->peer), ntohl (qm->quota.value__));
594 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, qm->quota);
597 LOG (GNUNET_ERROR_TYPE_ERROR,
598 _("Received unexpected message of type %u in %s:%u\n"),
599 ntohs (msg->type), __FILE__, __LINE__);
607 * A transmission request could not be satisfied because of
608 * network congestion. Notify the initiator and clean up.
610 * @param cls the 'struct GNUNET_TRANSPORT_TransmitHandle'
611 * @param tc scheduler context
614 timeout_request_due_to_congestion (void *cls,
615 const struct GNUNET_SCHEDULER_TaskContext
618 struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
619 struct Neighbour *n = th->neighbour;
621 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
622 GNUNET_assert (th == n->th);
623 GNUNET_assert (NULL == n->hn);
625 th->notify (th->notify_cls, 0, NULL);
631 * Transmit message(s) to service.
633 * @param cls handle to transport
634 * @param size number of bytes available in buf
635 * @param buf where to copy the message
636 * @return number of bytes copied to buf
639 transport_notify_ready (void *cls, size_t size, void *buf)
641 struct GNUNET_TRANSPORT_Handle *h = cls;
642 struct GNUNET_TRANSPORT_TransmitHandle *th;
645 struct OutboundMessage obm;
650 GNUNET_assert (NULL != h->client);
654 /* transmission failed */
655 disconnect_and_schedule_reconnect (h);
661 /* first send control messages */
662 while ((NULL != (th = h->control_head)) && (th->notify_size <= size))
664 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
665 nret = th->notify (th->notify_cls, size, &cbuf[ret]);
666 LOG (GNUNET_ERROR_TYPE_DEBUG, "Added %u bytes of control message at %u\n",
673 /* then, if possible and no control messages pending, send data messages */
674 while ((NULL == h->control_head) &&
675 (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))))
677 if (GNUNET_YES != n->is_ready)
679 /* peer not ready, wait for notification! */
680 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
682 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == n->th->timeout_task);
683 n->th->timeout_task =
684 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
686 &timeout_request_due_to_congestion,
691 if (th->notify_size + sizeof (struct OutboundMessage) > size)
692 break; /* does not fit */
693 if (GNUNET_BANDWIDTH_tracker_get_delay
694 (&n->out_tracker, th->notify_size).rel_value > 0)
695 break; /* too early */
696 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
699 n->is_ready = GNUNET_NO;
700 GNUNET_assert (size >= sizeof (struct OutboundMessage));
702 th->notify (th->notify_cls, size - sizeof (struct OutboundMessage),
703 &cbuf[ret + sizeof (struct OutboundMessage)]);
704 GNUNET_assert (mret <= size - sizeof (struct OutboundMessage));
707 GNUNET_assert (mret + sizeof (struct OutboundMessage) <
708 GNUNET_SERVER_MAX_MESSAGE_SIZE);
709 obm.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND);
710 obm.header.size = htons (mret + sizeof (struct OutboundMessage));
711 obm.priority = htonl (th->priority);
713 GNUNET_TIME_relative_hton (GNUNET_TIME_absolute_get_remaining
716 memcpy (&cbuf[ret], &obm, sizeof (struct OutboundMessage));
717 ret += (mret + sizeof (struct OutboundMessage));
718 size -= (mret + sizeof (struct OutboundMessage));
719 GNUNET_BANDWIDTH_tracker_consume (&n->out_tracker, mret);
723 /* if there are more pending messages, try to schedule those */
724 schedule_transmission (h);
725 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u bytes to transport service\n",
732 * Schedule the task to send one message, either from the control
733 * list or the peer message queues to the service.
735 * @param cls transport service to schedule a transmission for
736 * @param tc scheduler context
739 schedule_transmission_task (void *cls,
740 const struct GNUNET_SCHEDULER_TaskContext *tc)
742 struct GNUNET_TRANSPORT_Handle *h = cls;
744 struct GNUNET_TRANSPORT_TransmitHandle *th;
747 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
748 GNUNET_assert (NULL != h->client);
749 /* destroy all requests that have timed out */
750 while ((NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))) &&
751 (GNUNET_TIME_absolute_get_remaining (n->th->timeout).rel_value == 0))
753 /* notify client that the request could not be satisfied within
754 * the given time constraints */
757 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
759 LOG (GNUNET_ERROR_TYPE_DEBUG,
760 "Signalling timeout for transmission to peer %s due to congestion\n",
761 GNUNET_i2s (&n->id));
762 GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
767 if (NULL != h->control_head)
769 size = h->control_head->notify_size;
773 n = GNUNET_CONTAINER_heap_peek (h->ready_heap);
775 return; /* no pending messages */
776 size = n->th->notify_size + sizeof (struct OutboundMessage);
778 LOG (GNUNET_ERROR_TYPE_DEBUG, "Calling notify_transmit_ready\n");
780 GNUNET_CLIENT_notify_transmit_ready (h->client, size,
781 GNUNET_TIME_UNIT_FOREVER_REL,
782 GNUNET_NO, &transport_notify_ready,
784 GNUNET_assert (NULL != h->cth);
789 * Schedule the task to send one message, either from the control
790 * list or the peer message queues to the service.
792 * @param h transport service to schedule a transmission for
795 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h)
797 struct GNUNET_TIME_Relative delay;
800 GNUNET_assert (NULL != h->client);
801 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
803 GNUNET_SCHEDULER_cancel (h->quota_task);
804 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
806 if (NULL != h->control_head)
807 delay = GNUNET_TIME_UNIT_ZERO;
808 else if (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap)))
811 GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker,
812 n->th->notify_size + n->traffic_overhead);
813 n->traffic_overhead = 0;
816 return; /* no work to be done */
817 LOG (GNUNET_ERROR_TYPE_DEBUG,
818 "Scheduling next transmission to service in %llu ms\n",
819 (unsigned long long) delay.rel_value);
821 GNUNET_SCHEDULER_add_delayed (delay, &schedule_transmission_task, h);
826 * Queue control request for transmission to the transport
829 * @param h handle to the transport service
830 * @param size number of bytes to be transmitted
831 * @param notify function to call to get the content
832 * @param notify_cls closure for notify
835 schedule_control_transmit (struct GNUNET_TRANSPORT_Handle *h, size_t size,
836 GNUNET_CONNECTION_TransmitReadyNotify notify,
839 struct GNUNET_TRANSPORT_TransmitHandle *th;
841 LOG (GNUNET_ERROR_TYPE_DEBUG, "Control transmit of %u bytes requested\n",
843 th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle));
845 th->notify_cls = notify_cls;
846 th->notify_size = size;
847 GNUNET_CONTAINER_DLL_insert_tail (h->control_head, h->control_tail, th);
848 schedule_transmission (h);
853 * Transmit START message to service.
856 * @param size number of bytes available in buf
857 * @param buf where to copy the message
858 * @return number of bytes copied to buf
861 send_start (void *cls, size_t size, void *buf)
863 struct GNUNET_TRANSPORT_Handle *h = cls;
864 struct StartMessage s;
869 /* Can only be shutdown, just give up */
870 LOG (GNUNET_ERROR_TYPE_DEBUG,
871 "Shutdown while trying to transmit `%s' request.\n", "START");
874 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "START");
875 GNUNET_assert (size >= sizeof (struct StartMessage));
876 s.header.size = htons (sizeof (struct StartMessage));
877 s.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_START);
883 s.options = htonl (options);
885 memcpy (buf, &s, sizeof (struct StartMessage));
886 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
887 GNUNET_TIME_UNIT_FOREVER_REL);
888 return sizeof (struct StartMessage);
893 * Try again to connect to transport service.
895 * @param cls the handle to the transport service
896 * @param tc scheduler context
899 reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
901 struct GNUNET_TRANSPORT_Handle *h = cls;
903 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
904 if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
906 /* shutdown, just give up */
909 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connecting to transport service.\n");
910 GNUNET_assert (h->client == NULL);
911 GNUNET_assert (h->control_head == NULL);
912 GNUNET_assert (h->control_tail == NULL);
913 h->client = GNUNET_CLIENT_connect ("transport", h->cfg);
914 GNUNET_assert (h->client != NULL);
915 schedule_control_transmit (h, sizeof (struct StartMessage), &send_start, h);
920 * Function that will schedule the job that will try
921 * to connect us again to the client.
923 * @param h transport service to reconnect
926 disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h)
928 struct GNUNET_TRANSPORT_TransmitHandle *th;
930 GNUNET_assert (h->reconnect_task == GNUNET_SCHEDULER_NO_TASK);
933 GNUNET_CLIENT_notify_transmit_ready_cancel (h->cth);
936 if (NULL != h->client)
938 GNUNET_CLIENT_disconnect (h->client);
941 /* Forget about all neighbours that we used to be connected to */
942 GNUNET_CONTAINER_multihashmap_iterate (h->neighbours, &neighbour_delete, h);
943 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
945 GNUNET_SCHEDULER_cancel (h->quota_task);
946 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
948 while ((NULL != (th = h->control_head)))
950 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
951 th->notify (th->notify_cls, 0, NULL);
954 LOG (GNUNET_ERROR_TYPE_DEBUG,
955 "Scheduling task to reconnect to transport service in %llu ms.\n",
956 h->reconnect_delay.rel_value);
958 GNUNET_SCHEDULER_add_delayed (h->reconnect_delay, &reconnect, h);
959 h->reconnect_delay = GNUNET_TIME_STD_BACKOFF (h->reconnect_delay);
964 * Send REQUEST_CONNECT message to the service.
966 * @param cls the 'struct GNUNET_PeerIdentity'
967 * @param size number of bytes available in buf
968 * @param buf where to copy the message
969 * @return number of bytes copied to buf
972 send_try_connect (void *cls, size_t size, void *buf)
974 struct GNUNET_PeerIdentity *pid = cls;
975 struct TransportRequestConnectMessage msg;
982 LOG (GNUNET_ERROR_TYPE_DEBUG,
983 "Transmitting `%s' request with respect to `%4s'.\n", "REQUEST_CONNECT",
985 GNUNET_assert (size >= sizeof (struct TransportRequestConnectMessage));
986 msg.header.size = htons (sizeof (struct TransportRequestConnectMessage));
987 msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_CONNECT);
988 msg.reserved = htonl (0);
990 memcpy (buf, &msg, sizeof (msg));
992 return sizeof (struct TransportRequestConnectMessage);
996 * Ask the transport service to establish a connection to
999 * @param handle connection to transport service
1000 * @param target who we should try to connect to
1001 * @return GNUNET_OK if request can be scheduled
1002 * GNUNET_NO please retry later because we are reconnecting
1003 * GNUNET_SYSERR on failure
1006 GNUNET_TRANSPORT_try_connect (struct GNUNET_TRANSPORT_Handle *handle,
1007 const struct GNUNET_PeerIdentity *target)
1009 struct GNUNET_PeerIdentity *pid;
1010 if (NULL == handle->client)
1012 if (GNUNET_SCHEDULER_NO_TASK == handle->reconnect_task)
1013 return GNUNET_SYSERR; /* this should never happen */
1015 return GNUNET_NO; /* please retry */
1018 pid = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
1020 schedule_control_transmit (handle,
1021 sizeof (struct TransportRequestConnectMessage),
1022 &send_try_connect, pid);
1027 struct SendHelloContext
1029 GNUNET_SCHEDULER_Task cont;
1033 struct GNUNET_MessageHeader *msg;
1037 * Send HELLO message to the service.
1039 * @param cls the HELLO message to send
1040 * @param size number of bytes available in buf
1041 * @param buf where to copy the message
1042 * @return number of bytes copied to buf
1045 send_hello (void *cls, size_t size, void *buf)
1047 struct SendHelloContext *shc = cls;
1048 struct GNUNET_MessageHeader *msg = shc->msg;
1050 struct GNUNET_SCHEDULER_TaskContext tc;
1051 tc.read_ready = NULL;
1052 tc.write_ready = NULL;
1053 tc.reason = GNUNET_SCHEDULER_REASON_TIMEOUT;
1057 LOG (GNUNET_ERROR_TYPE_DEBUG,
1058 "Timeout while trying to transmit `%s' request.\n", "HELLO");
1059 if (NULL != shc->cont)
1060 shc->cont (shc->cls, &tc);
1065 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "HELLO");
1066 ssize = ntohs (msg->size);
1067 GNUNET_assert (size >= ssize);
1068 memcpy (buf, msg, ssize);
1070 tc.reason = GNUNET_SCHEDULER_REASON_READ_READY;
1071 if (NULL != shc->cont)
1072 shc->cont (shc->cls, &tc);
1079 * Offer the transport service the HELLO of another peer. Note that
1080 * the transport service may just ignore this message if the HELLO is
1081 * malformed or useless due to our local configuration.
1083 * @param handle connection to transport service
1084 * @param hello the hello message
1085 * @param cont continuation to call when HELLO has been sent,
1086 * tc reason GNUNET_SCHEDULER_REASON_TIMEOUT for fail
1087 * tc reasong GNUNET_SCHEDULER_REASON_READ_READY for success
1088 * @param cls closure for continuation
1092 GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle,
1093 const struct GNUNET_MessageHeader *hello,
1094 GNUNET_SCHEDULER_Task cont, void *cls)
1097 struct GNUNET_PeerIdentity peer;
1098 struct GNUNET_MessageHeader *msg;
1099 struct SendHelloContext * shc;
1100 struct GNUNET_SCHEDULER_TaskContext tc;
1102 tc.read_ready = NULL;
1103 tc.write_ready = NULL;
1104 tc.reason = GNUNET_SCHEDULER_REASON_TIMEOUT;
1106 if (NULL == handle->client)
1112 GNUNET_break (ntohs (hello->type) == GNUNET_MESSAGE_TYPE_HELLO);
1113 size = ntohs (hello->size);
1114 GNUNET_break (size >= sizeof (struct GNUNET_MessageHeader));
1116 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) hello, &peer))
1124 msg = GNUNET_malloc (size);
1125 memcpy (msg, hello, size);
1126 LOG (GNUNET_ERROR_TYPE_DEBUG,
1127 "Offering `%s' message of `%4s' to transport for validation.\n", "HELLO",
1128 GNUNET_i2s (&peer));
1129 shc = GNUNET_malloc (sizeof (struct SendHelloContext));
1133 schedule_control_transmit (handle, size, &send_hello, shc);
1138 * Obtain the HELLO message for this peer.
1140 * @param handle connection to transport service
1141 * @param rec function to call with the HELLO, sender will be our peer
1142 * identity; message and sender will be NULL on timeout
1143 * (handshake with transport service pending/failed).
1144 * cost estimate will be 0.
1145 * @param rec_cls closure for rec
1146 * @return handle to cancel the operation
1148 struct GNUNET_TRANSPORT_GetHelloHandle *
1149 GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle,
1150 GNUNET_TRANSPORT_HelloUpdateCallback rec,
1153 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
1155 hwl = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_GetHelloHandle));
1157 hwl->rec_cls = rec_cls;
1158 hwl->handle = handle;
1159 GNUNET_CONTAINER_DLL_insert (handle->hwl_head, handle->hwl_tail, hwl);
1160 if (handle->my_hello != NULL)
1161 rec (rec_cls, (const struct GNUNET_MessageHeader *) handle->my_hello);
1167 * Stop receiving updates about changes to our HELLO message.
1169 * @param ghh handle to cancel
1172 GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_GetHelloHandle *ghh)
1174 struct GNUNET_TRANSPORT_Handle *handle = ghh->handle;
1176 GNUNET_CONTAINER_DLL_remove (handle->hwl_head, handle->hwl_tail, ghh);
1182 * Connect to the transport service. Note that the connection may
1183 * complete (or fail) asynchronously.
1185 * @param cfg configuration to use
1186 * @param self our own identity (API should check that it matches
1187 * the identity found by transport), or NULL (no check)
1188 * @param cls closure for the callbacks
1189 * @param rec receive function to call
1190 * @param nc function to call on connect events
1191 * @param nd function to call on disconnect events
1193 struct GNUNET_TRANSPORT_Handle *
1194 GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
1195 const struct GNUNET_PeerIdentity *self, void *cls,
1196 GNUNET_TRANSPORT_ReceiveCallback rec,
1197 GNUNET_TRANSPORT_NotifyConnect nc,
1198 GNUNET_TRANSPORT_NotifyDisconnect nd)
1200 struct GNUNET_TRANSPORT_Handle *ret;
1202 ret = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_Handle));
1206 ret->check_self = GNUNET_YES;
1213 ret->reconnect_delay = GNUNET_TIME_UNIT_ZERO;
1215 GNUNET_CONTAINER_multihashmap_create (STARTING_NEIGHBOURS_SIZE, GNUNET_YES);
1217 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1218 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connecting to transport service.\n");
1219 ret->client = GNUNET_CLIENT_connect ("transport", cfg);
1220 if (ret->client == NULL)
1225 schedule_control_transmit (ret, sizeof (struct StartMessage), &send_start, ret);
1231 * Disconnect from the transport service.
1233 * @param handle handle to the service as returned from GNUNET_TRANSPORT_connect
1236 GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle)
1238 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transport disconnect called!\n");
1239 /* this disconnects all neighbours... */
1240 if (handle->reconnect_task == GNUNET_SCHEDULER_NO_TASK)
1241 disconnect_and_schedule_reconnect (handle);
1242 /* and now we stop trying to connect again... */
1243 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
1245 GNUNET_SCHEDULER_cancel (handle->reconnect_task);
1246 handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1248 GNUNET_CONTAINER_multihashmap_destroy (handle->neighbours);
1249 handle->neighbours = NULL;
1250 if (handle->quota_task != GNUNET_SCHEDULER_NO_TASK)
1252 GNUNET_SCHEDULER_cancel (handle->quota_task);
1253 handle->quota_task = GNUNET_SCHEDULER_NO_TASK;
1255 GNUNET_free_non_null (handle->my_hello);
1256 handle->my_hello = NULL;
1257 GNUNET_assert (handle->hwl_head == NULL);
1258 GNUNET_assert (handle->hwl_tail == NULL);
1259 GNUNET_CONTAINER_heap_destroy (handle->ready_heap);
1260 handle->ready_heap = NULL;
1261 GNUNET_free (handle);
1266 * Check if we could queue a message of the given size for
1267 * transmission. The transport service will take both its
1268 * internal buffers and bandwidth limits imposed by the
1269 * other peer into consideration when answering this query.
1271 * @param handle connection to transport service
1272 * @param target who should receive the message
1273 * @param size how big is the message we want to transmit?
1274 * @param priority how important is the message?
1275 * @param timeout after how long should we give up (and call
1276 * notify with buf NULL and size 0)?
1277 * @param notify function to call when we are ready to
1278 * send such a message
1279 * @param notify_cls closure for notify
1280 * @return NULL if someone else is already waiting to be notified
1281 * non-NULL if the notify callback was queued (can be used to cancel
1282 * using GNUNET_TRANSPORT_notify_transmit_ready_cancel)
1284 struct GNUNET_TRANSPORT_TransmitHandle *
1285 GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle,
1286 const struct GNUNET_PeerIdentity
1287 *target, size_t size, uint32_t priority,
1288 struct GNUNET_TIME_Relative timeout,
1289 GNUNET_CONNECTION_TransmitReadyNotify
1290 notify, void *notify_cls)
1292 struct Neighbour *n;
1293 struct GNUNET_TRANSPORT_TransmitHandle *th;
1294 struct GNUNET_TIME_Relative delay;
1296 n = neighbour_find (handle, target);
1299 /* use GNUNET_TRANSPORT_try_connect first, only use this function
1300 * once a connection has been established */
1306 /* attempt to send two messages at the same time to the same peer */
1310 GNUNET_assert (NULL == n->hn);
1311 th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle));
1313 th->notify = notify;
1314 th->notify_cls = notify_cls;
1315 th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1316 th->notify_size = size;
1317 th->priority = priority;
1319 /* calculate when our transmission should be ready */
1320 delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, size + n->traffic_overhead);
1321 n->traffic_overhead = 0;
1322 if (delay.rel_value > timeout.rel_value)
1323 delay.rel_value = 0; /* notify immediately (with failure) */
1324 LOG (GNUNET_ERROR_TYPE_DEBUG,
1325 "Bandwidth tracker allows next transmission to peer %s in %llu ms\n",
1326 GNUNET_i2s (target), (unsigned long long) delay.rel_value);
1327 n->hn = GNUNET_CONTAINER_heap_insert (handle->ready_heap, n, delay.rel_value);
1328 schedule_transmission (handle);
1334 * Cancel the specified transmission-ready notification.
1336 * @param th handle returned from GNUNET_TRANSPORT_notify_transmit_ready
1339 GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct
1340 GNUNET_TRANSPORT_TransmitHandle
1343 struct Neighbour *n;
1345 GNUNET_assert (NULL == th->next);
1346 GNUNET_assert (NULL == th->prev);
1348 GNUNET_assert (th == n->th);
1352 GNUNET_CONTAINER_heap_remove_node (n->hn);
1357 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != th->timeout_task);
1358 GNUNET_SCHEDULER_cancel (th->timeout_task);
1359 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
1365 /* end of transport_api.c */