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.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
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?
153 * Linked list of functions to call whenever our HELLO is updated.
155 struct GNUNET_TRANSPORT_GetHelloHandle
159 * This is a doubly linked list.
161 struct GNUNET_TRANSPORT_GetHelloHandle *next;
164 * This is a doubly linked list.
166 struct GNUNET_TRANSPORT_GetHelloHandle *prev;
171 struct GNUNET_TRANSPORT_Handle *handle;
174 * Callback to call once we got our HELLO.
176 GNUNET_TRANSPORT_HelloUpdateCallback rec;
187 * Handle for the transport service (includes all of the
188 * state for the transport service).
190 struct GNUNET_TRANSPORT_Handle
194 * Closure for the callbacks.
199 * Function to call for received data.
201 GNUNET_TRANSPORT_ReceiveCallback rec;
204 * function to call on connect events
206 GNUNET_TRANSPORT_NotifyConnect nc_cb;
209 * function to call on disconnect events
211 GNUNET_TRANSPORT_NotifyDisconnect nd_cb;
214 * Head of DLL of control messages.
216 struct GNUNET_TRANSPORT_TransmitHandle *control_head;
219 * Tail of DLL of control messages.
221 struct GNUNET_TRANSPORT_TransmitHandle *control_tail;
224 * The current HELLO message for this peer. Updated
225 * whenever transports change their addresses.
227 struct GNUNET_HELLO_Message *my_hello;
230 * My client connection to the transport service.
232 struct GNUNET_CLIENT_Connection *client;
235 * Handle to our registration with the client for notification.
237 struct GNUNET_CLIENT_TransmitHandle *cth;
240 * Linked list of pending requests for our HELLO.
242 struct GNUNET_TRANSPORT_GetHelloHandle *hwl_head;
245 * Linked list of pending requests for our HELLO.
247 struct GNUNET_TRANSPORT_GetHelloHandle *hwl_tail;
252 const struct GNUNET_CONFIGURATION_Handle *cfg;
255 * Hash map of the current connected neighbours of this peer.
256 * Maps peer identities to 'struct Neighbour' entries.
258 struct GNUNET_CONTAINER_MultiHashMap *neighbours;
261 * Heap sorting peers with pending messages by the timestamps that
262 * specify when we could next send a message to the respective peer.
263 * Excludes control messages (which can always go out immediately).
264 * Maps time stamps to 'struct Neighbour' entries.
266 struct GNUNET_CONTAINER_Heap *ready_heap;
269 * Peer identity as assumed by this process, or all zeros.
271 struct GNUNET_PeerIdentity self;
274 * ID of the task trying to reconnect to the service.
276 GNUNET_SCHEDULER_TaskIdentifier reconnect_task;
279 * ID of the task trying to trigger transmission for a peer while
280 * maintaining bandwidth quotas. In use if there are no control
281 * messages and the smallest entry in the 'ready_heap' has a time
282 * stamp in the future.
284 GNUNET_SCHEDULER_TaskIdentifier quota_task;
287 * Delay until we try to reconnect.
289 struct GNUNET_TIME_Relative reconnect_delay;
292 * Should we check that 'self' matches what the service thinks?
293 * (if GNUNET_NO, then 'self' is all zeros!).
300 * Schedule the task to send one message, either from the control
301 * list or the peer message queues to the service.
303 * @param h transport service to schedule a transmission for
306 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h);
310 * Function that will schedule the job that will try
311 * to connect us again to the client.
313 * @param h transport service to reconnect
316 disconnect_and_schedule_reconnect (struct GNUNET_TRANSPORT_Handle *h);
320 * Get the neighbour list entry for the given peer
322 * @param h our context
323 * @param peer peer to look up
324 * @return NULL if no such peer entry exists
326 static struct Neighbour *
327 neighbour_find (struct GNUNET_TRANSPORT_Handle *h,
328 const struct GNUNET_PeerIdentity *peer)
330 return GNUNET_CONTAINER_multihashmap_get (h->neighbours, &peer->hashPubKey);
335 * Add neighbour to our list
337 * @return NULL if this API is currently disconnecting from the service
339 static struct Neighbour *
340 neighbour_add (struct GNUNET_TRANSPORT_Handle *h,
341 const struct GNUNET_PeerIdentity *pid)
345 #if DEBUG_TRANSPORT_API
346 LOG (GNUNET_ERROR_TYPE_DEBUG, "Creating entry for neighbour `%4s'.\n",
349 n = GNUNET_malloc (sizeof (struct Neighbour));
352 n->is_ready = GNUNET_YES;
353 GNUNET_BANDWIDTH_tracker_init (&n->out_tracker,
354 GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
355 MAX_BANDWIDTH_CARRY_S);
356 GNUNET_assert (GNUNET_OK ==
357 GNUNET_CONTAINER_multihashmap_put (h->neighbours,
359 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
365 * Iterator over hash map entries, for deleting state of a neighbour.
367 * @param cls the 'struct GNUNET_TRANSPORT_Handle*'
368 * @param key peer identity
369 * @param value value in the hash map, the neighbour entry to delete
370 * @return GNUNET_YES if we should continue to
375 neighbour_delete (void *cls, const GNUNET_HashCode * key, void *value)
377 struct GNUNET_TRANSPORT_Handle *handle = cls;
378 struct Neighbour *n = value;
380 if (NULL != handle->nd_cb)
381 handle->nd_cb (handle->cls, &n->id);
382 GNUNET_assert (NULL == n->th);
383 GNUNET_assert (NULL == n->hn);
384 GNUNET_assert (GNUNET_YES ==
385 GNUNET_CONTAINER_multihashmap_remove (handle->neighbours, key,
393 * Function we use for handling incoming messages.
395 * @param cls closure (struct GNUNET_TRANSPORT_Handle *)
396 * @param msg message received, NULL on timeout or fatal error
399 demultiplexer (void *cls, const struct GNUNET_MessageHeader *msg)
401 struct GNUNET_TRANSPORT_Handle *h = cls;
402 const struct DisconnectInfoMessage *dim;
403 const struct ConnectInfoMessage *cim;
404 const struct InboundMessage *im;
405 const struct GNUNET_MessageHeader *imm;
406 const struct SendOkMessage *okm;
407 const struct QuotaSetMessage *qm;
408 const struct GNUNET_ATS_Information *ats;
409 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
410 struct GNUNET_TRANSPORT_GetHelloHandle *next_hwl;
412 struct GNUNET_PeerIdentity me;
416 GNUNET_assert (h->client != NULL);
419 #if DEBUG_TRANSPORT_API
420 LOG (GNUNET_ERROR_TYPE_INFO,
421 "Error receiving from transport service, disconnecting temporarily.\n");
423 disconnect_and_schedule_reconnect (h);
426 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
427 GNUNET_TIME_UNIT_FOREVER_REL);
428 size = ntohs (msg->size);
429 switch (ntohs (msg->type))
431 case GNUNET_MESSAGE_TYPE_HELLO:
433 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) msg, &me))
438 #if DEBUG_TRANSPORT_API
439 LOG (GNUNET_ERROR_TYPE_DEBUG,
440 "Receiving (my own) `%s' message, I am `%4s'.\n", "HELLO",
443 GNUNET_free_non_null (h->my_hello);
445 if (size < sizeof (struct GNUNET_MessageHeader))
450 h->my_hello = GNUNET_malloc (size);
451 memcpy (h->my_hello, msg, size);
455 next_hwl = hwl->next;
456 hwl->rec (hwl->rec_cls,
457 (const struct GNUNET_MessageHeader *) h->my_hello);
461 case GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT:
462 if (size < sizeof (struct ConnectInfoMessage))
467 cim = (const struct ConnectInfoMessage *) msg;
468 ats_count = ntohl (cim->ats_count);
470 sizeof (struct ConnectInfoMessage) +
471 ats_count * sizeof (struct GNUNET_ATS_Information))
476 ats = (const struct GNUNET_ATS_Information*) &cim[1];
477 #if DEBUG_TRANSPORT_API
478 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n",
479 "CONNECT", GNUNET_i2s (&cim->id));
481 n = neighbour_find (h, &cim->id);
487 n = neighbour_add (h, &cim->id);
488 if (h->nc_cb != NULL)
489 h->nc_cb (h->cls, &n->id, ats, ats_count);
491 case GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT:
492 if (size != sizeof (struct DisconnectInfoMessage))
497 dim = (const struct DisconnectInfoMessage *) msg;
498 GNUNET_break (ntohl (dim->reserved) == 0);
499 #if DEBUG_TRANSPORT_API_DISCONNECT
500 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message for `%4s'.\n",
501 "DISCONNECT", GNUNET_i2s (&dim->peer));
503 n = neighbour_find (h, &dim->peer);
509 neighbour_delete (h, &dim->peer.hashPubKey, n);
511 case GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK:
512 if (size != sizeof (struct SendOkMessage))
517 okm = (const struct SendOkMessage *) msg;
518 #if DEBUG_TRANSPORT_API
519 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message, transmission %s.\n",
520 "SEND_OK", ntohl (okm->success) == GNUNET_OK ? "succeeded" : "failed");
522 n = neighbour_find (h, &okm->peer);
525 GNUNET_break (GNUNET_NO == n->is_ready);
526 n->is_ready = GNUNET_YES;
527 if ((n->th != NULL) && (n->hn == NULL))
529 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != n->th->timeout_task);
530 GNUNET_SCHEDULER_cancel (n->th->timeout_task);
531 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
532 /* we've been waiting for this (congestion, not quota,
533 * caused delayed transmission) */
534 n->hn = GNUNET_CONTAINER_heap_insert (h->ready_heap, n, 0);
535 schedule_transmission (h);
538 case GNUNET_MESSAGE_TYPE_TRANSPORT_RECV:
539 #if DEBUG_TRANSPORT_API
540 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message.\n", "RECV");
543 sizeof (struct InboundMessage) + sizeof (struct GNUNET_MessageHeader))
548 im = (const struct InboundMessage *) msg;
549 ats_count = ntohl (im->ats_count);
550 ats = (const struct GNUNET_ATS_Information*) &im[1];
551 imm = (const struct GNUNET_MessageHeader *) &ats[ats_count];
552 if (ntohs (imm->size) + sizeof (struct InboundMessage) +
553 ats_count * sizeof (struct GNUNET_ATS_Information) != size)
558 #if DEBUG_TRANSPORT_API
559 LOG (GNUNET_ERROR_TYPE_DEBUG, "Received message of type %u from `%4s'.\n",
560 ntohs (imm->type), GNUNET_i2s (&im->peer));
562 n = neighbour_find (h, &im->peer);
569 h->rec (h->cls, &im->peer, imm, ats, ats_count);
571 case GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA:
572 #if DEBUG_TRANSPORT_API
573 LOG (GNUNET_ERROR_TYPE_DEBUG, "Receiving `%s' message.\n", "SET_QUOTA");
575 if (size != sizeof (struct QuotaSetMessage))
580 qm = (const struct QuotaSetMessage *) msg;
581 n = neighbour_find (h, &qm->peer);
584 GNUNET_BANDWIDTH_tracker_update_quota (&n->out_tracker, qm->quota);
587 LOG (GNUNET_ERROR_TYPE_ERROR,
588 _("Received unexpected message of type %u in %s:%u\n"),
589 ntohs (msg->type), __FILE__, __LINE__);
597 * A transmission request could not be satisfied because of
598 * network congestion. Notify the initiator and clean up.
600 * @param cls the 'struct GNUNET_TRANSPORT_TransmitHandle'
601 * @param tc scheduler context
604 timeout_request_due_to_congestion (void *cls,
605 const struct GNUNET_SCHEDULER_TaskContext
608 struct GNUNET_TRANSPORT_TransmitHandle *th = cls;
609 struct Neighbour *n = th->neighbour;
611 n->th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
612 GNUNET_assert (th == n->th);
613 GNUNET_assert (NULL == n->hn);
615 th->notify (th->notify_cls, 0, NULL);
621 * Transmit message(s) to service.
623 * @param cls handle to transport
624 * @param size number of bytes available in buf
625 * @param buf where to copy the message
626 * @return number of bytes copied to buf
629 transport_notify_ready (void *cls, size_t size, void *buf)
631 struct GNUNET_TRANSPORT_Handle *h = cls;
632 struct GNUNET_TRANSPORT_TransmitHandle *th;
635 struct OutboundMessage obm;
640 GNUNET_assert (NULL != h->client);
644 /* transmission failed */
645 disconnect_and_schedule_reconnect (h);
651 /* first send control messages */
652 while ((NULL != (th = h->control_head)) && (th->notify_size <= size))
654 GNUNET_CONTAINER_DLL_remove (h->control_head, h->control_tail, th);
655 nret = th->notify (th->notify_cls, size, &cbuf[ret]);
656 #if DEBUG_TRANSPORT_API
657 LOG (GNUNET_ERROR_TYPE_DEBUG, "Added %u bytes of control message at %u\n",
665 /* then, if possible and no control messages pending, send data messages */
666 while ((NULL == h->control_head) &&
667 (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))))
669 if (GNUNET_YES != n->is_ready)
671 /* peer not ready, wait for notification! */
672 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
674 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == n->th->timeout_task);
675 n->th->timeout_task =
676 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_absolute_get_remaining
678 &timeout_request_due_to_congestion,
683 if (th->notify_size + sizeof (struct OutboundMessage) > size)
684 break; /* does not fit */
685 if (GNUNET_BANDWIDTH_tracker_get_delay
686 (&n->out_tracker, th->notify_size).rel_value > 0)
687 break; /* too early */
688 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
691 n->is_ready = GNUNET_NO;
692 GNUNET_assert (size >= sizeof (struct OutboundMessage));
694 th->notify (th->notify_cls, size - sizeof (struct OutboundMessage),
695 &cbuf[ret + sizeof (struct OutboundMessage)]);
696 GNUNET_assert (mret <= size - sizeof (struct OutboundMessage));
699 GNUNET_assert (mret + sizeof (struct OutboundMessage) <
700 GNUNET_SERVER_MAX_MESSAGE_SIZE);
701 obm.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND);
702 obm.header.size = htons (mret + sizeof (struct OutboundMessage));
703 obm.priority = htonl (th->priority);
705 GNUNET_TIME_relative_hton (GNUNET_TIME_absolute_get_remaining
708 memcpy (&cbuf[ret], &obm, sizeof (struct OutboundMessage));
709 ret += (mret + sizeof (struct OutboundMessage));
710 size -= (mret + sizeof (struct OutboundMessage));
711 if (NULL == getenv ("infinite-bandwidth"))
712 GNUNET_BANDWIDTH_tracker_consume (&n->out_tracker, mret);
716 /* if there are more pending messages, try to schedule those */
717 schedule_transmission (h);
718 #if DEBUG_TRANSPORT_API
719 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u bytes to transport service\n",
727 * Schedule the task to send one message, either from the control
728 * list or the peer message queues to the service.
730 * @param cls transport service to schedule a transmission for
731 * @param tc scheduler context
734 schedule_transmission_task (void *cls,
735 const struct GNUNET_SCHEDULER_TaskContext *tc)
737 struct GNUNET_TRANSPORT_Handle *h = cls;
739 struct GNUNET_TRANSPORT_TransmitHandle *th;
742 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
743 GNUNET_assert (NULL != h->client);
744 /* destroy all requests that have timed out */
745 while ((NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap))) &&
746 (GNUNET_TIME_absolute_get_remaining (n->th->timeout).rel_value == 0))
748 /* notify client that the request could not be satisfied within
749 * the given time constraints */
752 GNUNET_assert (n == GNUNET_CONTAINER_heap_remove_root (h->ready_heap));
754 #if DEBUG_TRANSPORT_API
755 LOG (GNUNET_ERROR_TYPE_DEBUG,
756 "Signalling timeout for transmission to peer %s due to congestion\n",
757 GNUNET_i2s (&n->id));
759 GNUNET_assert (0 == th->notify (th->notify_cls, 0, NULL));
764 if (NULL != h->control_head)
766 size = h->control_head->notify_size;
770 n = GNUNET_CONTAINER_heap_peek (h->ready_heap);
772 return; /* no pending messages */
773 size = n->th->notify_size + sizeof (struct OutboundMessage);
775 #if DEBUG_TRANSPORT_API
776 LOG (GNUNET_ERROR_TYPE_DEBUG, "Calling notify_transmit_ready\n");
779 GNUNET_CLIENT_notify_transmit_ready (h->client, size,
780 GNUNET_TIME_UNIT_FOREVER_REL,
781 GNUNET_NO, &transport_notify_ready,
783 GNUNET_assert (NULL != h->cth);
788 * Schedule the task to send one message, either from the control
789 * list or the peer message queues to the service.
791 * @param h transport service to schedule a transmission for
794 schedule_transmission (struct GNUNET_TRANSPORT_Handle *h)
796 struct GNUNET_TIME_Relative delay;
799 GNUNET_assert (NULL != h->client);
800 if (h->quota_task != GNUNET_SCHEDULER_NO_TASK)
802 GNUNET_SCHEDULER_cancel (h->quota_task);
803 h->quota_task = GNUNET_SCHEDULER_NO_TASK;
805 if (NULL != h->control_head)
806 delay = GNUNET_TIME_UNIT_ZERO;
807 else if (NULL != (n = GNUNET_CONTAINER_heap_peek (h->ready_heap)))
809 GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker,
812 return; /* no work to be done */
813 #if DEBUG_TRANSPORT_API
814 LOG (GNUNET_ERROR_TYPE_DEBUG,
815 "Scheduling next transmission to service in %llu ms\n",
816 (unsigned long long) delay.rel_value);
819 GNUNET_SCHEDULER_add_delayed (delay, &schedule_transmission_task, h);
824 * Queue control request for transmission to the transport
827 * @param h handle to the transport service
828 * @param size number of bytes to be transmitted
829 * @param notify function to call to get the content
830 * @param notify_cls closure for notify
833 schedule_control_transmit (struct GNUNET_TRANSPORT_Handle *h, size_t size,
834 GNUNET_CONNECTION_TransmitReadyNotify notify,
837 struct GNUNET_TRANSPORT_TransmitHandle *th;
839 #if DEBUG_TRANSPORT_API
840 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;
868 /* Can only be shutdown, just give up */
869 #if DEBUG_TRANSPORT_API
870 LOG (GNUNET_ERROR_TYPE_DEBUG,
871 "Shutdown while trying to transmit `%s' request.\n", "START");
875 #if DEBUG_TRANSPORT_API
876 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "START");
878 GNUNET_assert (size >= sizeof (struct StartMessage));
879 s.header.size = htons (sizeof (struct StartMessage));
880 s.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_START);
881 s.do_check = htonl (h->check_self);
883 memcpy (buf, &s, sizeof (struct StartMessage));
884 GNUNET_CLIENT_receive (h->client, &demultiplexer, h,
885 GNUNET_TIME_UNIT_FOREVER_REL);
886 return sizeof (struct StartMessage);
891 * Try again to connect to transport service.
893 * @param cls the handle to the transport service
894 * @param tc scheduler context
897 reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
899 struct GNUNET_TRANSPORT_Handle *h = cls;
901 h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
902 if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
904 /* shutdown, just give up */
907 #if DEBUG_TRANSPORT_API
908 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);
931 /* Forget about all neighbours that we used to be connected to */
932 GNUNET_CONTAINER_multihashmap_iterate (h->neighbours, &neighbour_delete, h);
935 GNUNET_CLIENT_notify_transmit_ready_cancel (h->cth);
938 if (NULL != h->client)
940 GNUNET_CLIENT_disconnect (h->client, GNUNET_YES);
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 #if DEBUG_TRANSPORT_API
955 LOG (GNUNET_ERROR_TYPE_DEBUG,
956 "Scheduling task to reconnect to transport service in %llu ms.\n",
957 h->reconnect_delay.rel_value);
960 GNUNET_SCHEDULER_add_delayed (h->reconnect_delay, &reconnect, h);
961 if (h->reconnect_delay.rel_value == 0)
963 h->reconnect_delay = GNUNET_TIME_UNIT_MILLISECONDS;
967 h->reconnect_delay = GNUNET_TIME_relative_multiply (h->reconnect_delay, 2);
969 GNUNET_TIME_relative_min (GNUNET_TIME_UNIT_SECONDS, h->reconnect_delay);
975 * Send REQUEST_CONNECT message to the service.
977 * @param cls the 'struct GNUNET_PeerIdentity'
978 * @param size number of bytes available in buf
979 * @param buf where to copy the message
980 * @return number of bytes copied to buf
983 send_try_connect (void *cls, size_t size, void *buf)
985 struct GNUNET_PeerIdentity *pid = cls;
986 struct TransportRequestConnectMessage msg;
993 #if DEBUG_TRANSPORT_API
994 LOG (GNUNET_ERROR_TYPE_DEBUG,
995 "Transmitting `%s' request with respect to `%4s'.\n", "REQUEST_CONNECT",
998 GNUNET_assert (size >= sizeof (struct TransportRequestConnectMessage));
999 msg.header.size = htons (sizeof (struct TransportRequestConnectMessage));
1000 msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_CONNECT);
1001 msg.reserved = htonl (0);
1003 memcpy (buf, &msg, sizeof (msg));
1005 return sizeof (struct TransportRequestConnectMessage);
1010 * Ask the transport service to establish a connection to
1013 * @param handle connection to transport service
1014 * @param target who we should try to connect to
1017 GNUNET_TRANSPORT_try_connect (struct GNUNET_TRANSPORT_Handle *handle,
1018 const struct GNUNET_PeerIdentity *target)
1020 struct GNUNET_PeerIdentity *pid;
1022 if (NULL == handle->client)
1024 pid = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity));
1026 schedule_control_transmit (handle,
1027 sizeof (struct TransportRequestConnectMessage),
1028 &send_try_connect, pid);
1033 * Send HELLO message to the service.
1035 * @param cls the HELLO message to send
1036 * @param size number of bytes available in buf
1037 * @param buf where to copy the message
1038 * @return number of bytes copied to buf
1041 send_hello (void *cls, size_t size, void *buf)
1043 struct GNUNET_MessageHeader *msg = cls;
1048 #if DEBUG_TRANSPORT_TIMEOUT
1049 LOG (GNUNET_ERROR_TYPE_DEBUG,
1050 "Timeout while trying to transmit `%s' request.\n", "HELLO");
1055 #if DEBUG_TRANSPORT_API
1056 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transmitting `%s' request.\n", "HELLO");
1058 ssize = ntohs (msg->size);
1059 GNUNET_assert (size >= ssize);
1060 memcpy (buf, msg, ssize);
1067 * Offer the transport service the HELLO of another peer. Note that
1068 * the transport service may just ignore this message if the HELLO is
1069 * malformed or useless due to our local configuration.
1071 * @param handle connection to transport service
1072 * @param hello the hello message
1073 * @param cont continuation to call when HELLO has been sent
1074 * @param cls closure for continuation
1078 GNUNET_TRANSPORT_offer_hello (struct GNUNET_TRANSPORT_Handle *handle,
1079 const struct GNUNET_MessageHeader *hello,
1080 GNUNET_SCHEDULER_Task cont, void *cls)
1083 struct GNUNET_PeerIdentity peer;
1084 struct GNUNET_MessageHeader *msg;
1086 if (NULL == handle->client)
1088 GNUNET_break (ntohs (hello->type) == GNUNET_MESSAGE_TYPE_HELLO);
1089 size = ntohs (hello->size);
1090 GNUNET_break (size >= sizeof (struct GNUNET_MessageHeader));
1092 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) hello, &peer))
1097 msg = GNUNET_malloc (size);
1098 memcpy (msg, hello, size);
1099 #if DEBUG_TRANSPORT_API
1100 LOG (GNUNET_ERROR_TYPE_DEBUG,
1101 "Offering `%s' message of `%4s' to transport for validation.\n", "HELLO",
1102 GNUNET_i2s (&peer));
1104 schedule_control_transmit (handle, size, &send_hello, msg);
1109 * Obtain the HELLO message for this peer.
1111 * @param handle connection to transport service
1112 * @param rec function to call with the HELLO, sender will be our peer
1113 * identity; message and sender will be NULL on timeout
1114 * (handshake with transport service pending/failed).
1115 * cost estimate will be 0.
1116 * @param rec_cls closure for rec
1117 * @return handle to cancel the operation
1119 struct GNUNET_TRANSPORT_GetHelloHandle *
1120 GNUNET_TRANSPORT_get_hello (struct GNUNET_TRANSPORT_Handle *handle,
1121 GNUNET_TRANSPORT_HelloUpdateCallback rec,
1124 struct GNUNET_TRANSPORT_GetHelloHandle *hwl;
1126 hwl = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_GetHelloHandle));
1128 hwl->rec_cls = rec_cls;
1129 hwl->handle = handle;
1130 GNUNET_CONTAINER_DLL_insert (handle->hwl_head, handle->hwl_tail, hwl);
1131 if (handle->my_hello != NULL)
1132 rec (rec_cls, (const struct GNUNET_MessageHeader *) handle->my_hello);
1138 * Stop receiving updates about changes to our HELLO message.
1140 * @param ghh handle to cancel
1143 GNUNET_TRANSPORT_get_hello_cancel (struct GNUNET_TRANSPORT_GetHelloHandle *ghh)
1145 struct GNUNET_TRANSPORT_Handle *handle = ghh->handle;
1147 GNUNET_CONTAINER_DLL_remove (handle->hwl_head, handle->hwl_tail, ghh);
1153 * Connect to the transport service. Note that the connection may
1154 * complete (or fail) asynchronously.
1156 * @param cfg configuration to use
1157 * @param self our own identity (API should check that it matches
1158 * the identity found by transport), or NULL (no check)
1159 * @param cls closure for the callbacks
1160 * @param rec receive function to call
1161 * @param nc function to call on connect events
1162 * @param nd function to call on disconnect events
1164 struct GNUNET_TRANSPORT_Handle *
1165 GNUNET_TRANSPORT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
1166 const struct GNUNET_PeerIdentity *self, void *cls,
1167 GNUNET_TRANSPORT_ReceiveCallback rec,
1168 GNUNET_TRANSPORT_NotifyConnect nc,
1169 GNUNET_TRANSPORT_NotifyDisconnect nd)
1171 struct GNUNET_TRANSPORT_Handle *ret;
1173 ret = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_Handle));
1177 ret->check_self = GNUNET_YES;
1184 ret->reconnect_delay = GNUNET_TIME_UNIT_ZERO;
1186 GNUNET_CONTAINER_multihashmap_create (STARTING_NEIGHBOURS_SIZE);
1188 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1189 ret->reconnect_task = GNUNET_SCHEDULER_add_now (&reconnect, ret);
1195 * Disconnect from the transport service.
1197 * @param handle handle to the service as returned from GNUNET_TRANSPORT_connect
1200 GNUNET_TRANSPORT_disconnect (struct GNUNET_TRANSPORT_Handle *handle)
1202 #if DEBUG_TRANSPORT_API
1203 LOG (GNUNET_ERROR_TYPE_DEBUG, "Transport disconnect called!\n");
1205 /* this disconnects all neighbours... */
1206 if (handle->reconnect_task == GNUNET_SCHEDULER_NO_TASK)
1207 disconnect_and_schedule_reconnect (handle);
1208 /* and now we stop trying to connect again... */
1209 if (handle->reconnect_task != GNUNET_SCHEDULER_NO_TASK)
1211 GNUNET_SCHEDULER_cancel (handle->reconnect_task);
1212 handle->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
1214 GNUNET_CONTAINER_multihashmap_destroy (handle->neighbours);
1215 handle->neighbours = NULL;
1216 if (handle->quota_task != GNUNET_SCHEDULER_NO_TASK)
1218 GNUNET_SCHEDULER_cancel (handle->quota_task);
1219 handle->quota_task = GNUNET_SCHEDULER_NO_TASK;
1221 GNUNET_free_non_null (handle->my_hello);
1222 handle->my_hello = NULL;
1223 GNUNET_assert (handle->hwl_head == NULL);
1224 GNUNET_assert (handle->hwl_tail == NULL);
1225 GNUNET_CONTAINER_heap_destroy (handle->ready_heap);
1226 handle->ready_heap = NULL;
1227 GNUNET_free (handle);
1232 * Check if we could queue a message of the given size for
1233 * transmission. The transport service will take both its
1234 * internal buffers and bandwidth limits imposed by the
1235 * other peer into consideration when answering this query.
1237 * @param handle connection to transport service
1238 * @param target who should receive the message
1239 * @param size how big is the message we want to transmit?
1240 * @param priority how important is the message?
1241 * @param timeout after how long should we give up (and call
1242 * notify with buf NULL and size 0)?
1243 * @param notify function to call when we are ready to
1244 * send such a message
1245 * @param notify_cls closure for notify
1246 * @return NULL if someone else is already waiting to be notified
1247 * non-NULL if the notify callback was queued (can be used to cancel
1248 * using GNUNET_TRANSPORT_notify_transmit_ready_cancel)
1250 struct GNUNET_TRANSPORT_TransmitHandle *
1251 GNUNET_TRANSPORT_notify_transmit_ready (struct GNUNET_TRANSPORT_Handle *handle,
1252 const struct GNUNET_PeerIdentity
1253 *target, size_t size, uint32_t priority,
1254 struct GNUNET_TIME_Relative timeout,
1255 GNUNET_CONNECTION_TransmitReadyNotify
1256 notify, void *notify_cls)
1258 struct Neighbour *n;
1259 struct GNUNET_TRANSPORT_TransmitHandle *th;
1260 struct GNUNET_TIME_Relative delay;
1262 n = neighbour_find (handle, target);
1265 /* use GNUNET_TRANSPORT_try_connect first, only use this function
1266 * once a connection has been established */
1272 /* attempt to send two messages at the same time to the same peer */
1276 GNUNET_assert (NULL == n->hn);
1277 th = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_TransmitHandle));
1279 th->notify = notify;
1280 th->notify_cls = notify_cls;
1281 th->timeout = GNUNET_TIME_relative_to_absolute (timeout);
1282 th->notify_size = size;
1283 th->priority = priority;
1285 /* calculate when our transmission should be ready */
1286 delay = GNUNET_BANDWIDTH_tracker_get_delay (&n->out_tracker, size);
1287 if (delay.rel_value > timeout.rel_value)
1288 delay.rel_value = 0; /* notify immediately (with failure) */
1289 #if DEBUG_TRANSPORT_API
1290 LOG (GNUNET_ERROR_TYPE_DEBUG,
1291 "Bandwidth tracker allows next transmission to peer %s in %llu ms\n",
1292 GNUNET_i2s (target), (unsigned long long) delay.rel_value);
1294 n->hn = GNUNET_CONTAINER_heap_insert (handle->ready_heap, n, delay.rel_value);
1295 schedule_transmission (handle);
1301 * Cancel the specified transmission-ready notification.
1303 * @param th handle returned from GNUNET_TRANSPORT_notify_transmit_ready
1306 GNUNET_TRANSPORT_notify_transmit_ready_cancel (struct
1307 GNUNET_TRANSPORT_TransmitHandle
1310 struct Neighbour *n;
1312 GNUNET_assert (NULL == th->next);
1313 GNUNET_assert (NULL == th->prev);
1315 GNUNET_assert (th == n->th);
1319 GNUNET_CONTAINER_heap_remove_node (n->hn);
1324 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK != th->timeout_task);
1325 GNUNET_SCHEDULER_cancel (th->timeout_task);
1326 th->timeout_task = GNUNET_SCHEDULER_NO_TASK;
1332 /* end of transport_api.c */