2 This file is part of GNUnet.
3 (C) 2009--2013 Christian Grothoff (and other contributing authors)
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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
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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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23 * @brief library to access the DV service
24 * @author Christian Grothoff
25 * @author Nathan Evans
28 #include "gnunet_util_lib.h"
29 #include "gnunet_dv_service.h"
30 #include "gnunet_protocols.h"
32 #include "gnunet_transport_plugin.h"
34 #define LOG(kind,...) GNUNET_log_from (kind, "dv-api",__VA_ARGS__)
38 * Information we track for each peer.
44 * Handle for a send operation.
46 struct GNUNET_DV_TransmitHandle
51 struct GNUNET_DV_TransmitHandle *next;
56 struct GNUNET_DV_TransmitHandle *prev;
59 * Handle to the service.
61 struct GNUNET_DV_ServiceHandle *sh;
64 * Function to call upon completion.
66 GNUNET_DV_MessageSentCallback cb;
74 * The actual message (allocated at the end of this struct).
76 const struct GNUNET_MessageHeader *msg;
79 * Destination for the message.
81 struct ConnectedPeer *target;
84 * UID of our message, if any.
92 * Information we track for each peer.
98 * Identity of the peer.
100 struct GNUNET_PeerIdentity pid;
103 * Head of DLL of transmission handles where we need
104 * to invoke a continuation when we are informed about
105 * successful transmission. The respective request
106 * has already been sent to the DV service.
108 struct GNUNET_DV_TransmitHandle *head;
111 * Tail of DLL of transmission handles where we need
112 * to invoke a continuation when we are informed about
113 * successful transmission. The respective request
114 * has already been sent to the DV service.
116 struct GNUNET_DV_TransmitHandle *tail;
122 * Handle to the DV service.
124 struct GNUNET_DV_ServiceHandle
128 * Connection to DV service.
130 struct GNUNET_CLIENT_Connection *client;
133 * Active request for transmission to DV service.
135 struct GNUNET_CLIENT_TransmitHandle *th;
140 const struct GNUNET_CONFIGURATION_Handle *cfg;
143 * Closure for the callbacks.
148 * Function to call on connect events.
150 GNUNET_DV_ConnectCallback connect_cb;
153 * Function to call on distance change events.
155 GNUNET_DV_DistanceChangedCallback distance_cb;
158 * Function to call on disconnect events.
160 GNUNET_DV_DisconnectCallback disconnect_cb;
163 * Function to call on receiving messages events.
165 GNUNET_DV_MessageReceivedCallback message_cb;
168 * Head of messages to transmit.
170 struct GNUNET_DV_TransmitHandle *th_head;
173 * Tail of messages to transmit.
175 struct GNUNET_DV_TransmitHandle *th_tail;
178 * Information tracked per connected peer. Maps peer
179 * identities to `struct ConnectedPeer` entries.
181 struct GNUNET_CONTAINER_MultiPeerMap *peers;
192 * Disconnect and then reconnect to the DV service.
194 * @param sh service handle
197 reconnect (struct GNUNET_DV_ServiceHandle *sh);
201 * Gives a message from our queue to the DV service.
203 * @param cls handle to the dv service (struct GNUNET_DV_ServiceHandle)
204 * @param size how many bytes can we send
205 * @param buf where to copy the message to send
206 * @return how many bytes we copied to @a buf
209 transmit_pending (void *cls, size_t size, void *buf)
211 struct GNUNET_DV_ServiceHandle *sh = cls;
213 struct GNUNET_DV_TransmitHandle *th;
224 while ( (NULL != (th = sh->th_head)) &&
225 (size - ret >= (tsize = ntohs (th->msg->size)) ))
227 GNUNET_CONTAINER_DLL_remove (sh->th_head,
230 memcpy (&cbuf[ret], th->msg, tsize);
235 GNUNET_CONTAINER_DLL_insert (th->target->head,
249 * Start sending messages from our queue to the service.
251 * @param sh service handle
254 start_transmit (struct GNUNET_DV_ServiceHandle *sh)
258 if (NULL == sh->th_head)
261 GNUNET_CLIENT_notify_transmit_ready (sh->client,
262 ntohs (sh->th_head->msg->size),
263 GNUNET_TIME_UNIT_FOREVER_REL,
265 &transmit_pending, sh);
270 * We got disconnected from the service and thus all of the
271 * pending send callbacks will never be confirmed. Clean up.
273 * @param cls the 'struct GNUNET_DV_ServiceHandle'
274 * @param key a peer identity
275 * @param value a `struct ConnectedPeer` to clean up
276 * @return #GNUNET_OK (continue to iterate)
279 cleanup_send_cb (void *cls,
280 const struct GNUNET_PeerIdentity *key,
283 struct GNUNET_DV_ServiceHandle *sh = cls;
284 struct ConnectedPeer *peer = value;
285 struct GNUNET_DV_TransmitHandle *th;
287 GNUNET_assert (GNUNET_YES ==
288 GNUNET_CONTAINER_multipeermap_remove (sh->peers,
291 sh->disconnect_cb (sh->cls,
293 while (NULL != (th = peer->head))
295 GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, th);
296 th->cb (th->cb_cls, GNUNET_SYSERR);
305 * Handles a message sent from the DV service to us.
306 * Parse it out and give it to the plugin.
308 * @param cls the handle to the DV API
309 * @param msg the message that was received
312 handle_message_receipt (void *cls,
313 const struct GNUNET_MessageHeader *msg)
315 struct GNUNET_DV_ServiceHandle *sh = cls;
316 const struct GNUNET_DV_ConnectMessage *cm;
317 const struct GNUNET_DV_DistanceUpdateMessage *dum;
318 const struct GNUNET_DV_DisconnectMessage *dm;
319 const struct GNUNET_DV_ReceivedMessage *rm;
320 const struct GNUNET_MessageHeader *payload;
321 const struct GNUNET_DV_AckMessage *ack;
322 struct GNUNET_DV_TransmitHandle *th;
323 struct GNUNET_DV_TransmitHandle *tn;
324 struct ConnectedPeer *peer;
328 /* Connection closed */
332 LOG (GNUNET_ERROR_TYPE_DEBUG,
333 "Received message of type %u from DV service\n",
334 (unsigned int) msg->type);
335 switch (ntohs (msg->type))
337 case GNUNET_MESSAGE_TYPE_DV_CONNECT:
338 if (ntohs (msg->size) != sizeof (struct GNUNET_DV_ConnectMessage))
344 cm = (const struct GNUNET_DV_ConnectMessage *) msg;
345 peer = GNUNET_CONTAINER_multipeermap_get (sh->peers,
353 peer = GNUNET_new (struct ConnectedPeer);
354 peer->pid = cm->peer;
355 GNUNET_assert (GNUNET_OK ==
356 GNUNET_CONTAINER_multipeermap_put (sh->peers,
359 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
360 sh->connect_cb (sh->cls,
362 ntohl (cm->distance), ntohl (cm->network));
364 case GNUNET_MESSAGE_TYPE_DV_DISTANCE_CHANGED:
365 if (ntohs (msg->size) != sizeof (struct GNUNET_DV_DistanceUpdateMessage))
371 dum = (const struct GNUNET_DV_DistanceUpdateMessage *) msg;
372 sh->distance_cb (sh->cls,
374 ntohl (dum->distance));
376 case GNUNET_MESSAGE_TYPE_DV_DISCONNECT:
377 if (ntohs (msg->size) != sizeof (struct GNUNET_DV_DisconnectMessage))
383 dm = (const struct GNUNET_DV_DisconnectMessage *) msg;
384 peer = GNUNET_CONTAINER_multipeermap_get (sh->peers,
393 while (NULL != (th = tn))
396 if (peer == th->target)
398 GNUNET_CONTAINER_DLL_remove (sh->th_head,
401 th->cb (th->cb_cls, GNUNET_SYSERR);
405 cleanup_send_cb (sh, &dm->peer, peer);
407 case GNUNET_MESSAGE_TYPE_DV_RECV:
408 if (ntohs (msg->size) < sizeof (struct GNUNET_DV_ReceivedMessage) + sizeof (struct GNUNET_MessageHeader))
414 rm = (const struct GNUNET_DV_ReceivedMessage *) msg;
415 payload = (const struct GNUNET_MessageHeader *) &rm[1];
416 if (ntohs (msg->size) != sizeof (struct GNUNET_DV_ReceivedMessage) + ntohs (payload->size))
422 sh->message_cb (sh->cls,
424 ntohl (rm->distance),
427 case GNUNET_MESSAGE_TYPE_DV_SEND_ACK:
428 case GNUNET_MESSAGE_TYPE_DV_SEND_NACK:
429 if (ntohs (msg->size) != sizeof (struct GNUNET_DV_AckMessage))
435 ack = (const struct GNUNET_DV_AckMessage *) msg;
436 peer = GNUNET_CONTAINER_multipeermap_get (sh->peers,
439 return; /* this happens, just ignore */
440 for (th = peer->head; NULL != th; th = th->next)
442 if (th->uid != ntohl (ack->uid))
444 LOG (GNUNET_ERROR_TYPE_DEBUG,
445 "Matched ACK for message to peer %s\n",
446 GNUNET_i2s (&ack->target));
447 GNUNET_CONTAINER_DLL_remove (peer->head,
451 (ntohs (ack->header.type) == GNUNET_MESSAGE_TYPE_DV_SEND_ACK)
462 GNUNET_CLIENT_receive (sh->client,
463 &handle_message_receipt, sh,
464 GNUNET_TIME_UNIT_FOREVER_REL);
469 * Transmit the start message to the DV service.
471 * @param cls the `struct GNUNET_DV_ServiceHandle *`
472 * @param size number of bytes available in buf
473 * @param buf where to copy the message
474 * @return number of bytes written to buf
477 transmit_start (void *cls,
481 struct GNUNET_DV_ServiceHandle *sh = cls;
482 struct GNUNET_MessageHeader start_message;
491 GNUNET_assert (size >= sizeof (start_message));
492 start_message.size = htons (sizeof (struct GNUNET_MessageHeader));
493 start_message.type = htons (GNUNET_MESSAGE_TYPE_DV_START);
494 memcpy (buf, &start_message, sizeof (start_message));
495 GNUNET_CLIENT_receive (sh->client,
496 &handle_message_receipt, sh,
497 GNUNET_TIME_UNIT_FOREVER_REL);
499 return sizeof (start_message);
504 * Disconnect and then reconnect to the DV service.
506 * @param sh service handle
509 reconnect (struct GNUNET_DV_ServiceHandle *sh)
513 GNUNET_CLIENT_notify_transmit_ready_cancel (sh->th);
516 if (NULL != sh->client)
518 GNUNET_CLIENT_disconnect (sh->client);
521 GNUNET_CONTAINER_multipeermap_iterate (sh->peers,
524 LOG (GNUNET_ERROR_TYPE_DEBUG,
525 "Connecting to DV service\n");
526 sh->client = GNUNET_CLIENT_connect ("dv", sh->cfg);
527 if (NULL == sh->client)
532 sh->th = GNUNET_CLIENT_notify_transmit_ready (sh->client,
533 sizeof (struct GNUNET_MessageHeader),
534 GNUNET_TIME_UNIT_FOREVER_REL,
542 * Connect to the DV service.
544 * @param cfg configuration
545 * @param cls closure for callbacks
546 * @param connect_cb function to call on connects
547 * @param distance_cb function to call if distances change
548 * @param disconnect_cb function to call on disconnects
549 * @param message_cb function to call if we receive messages
550 * @return handle to access the service
552 struct GNUNET_DV_ServiceHandle *
553 GNUNET_DV_service_connect (const struct GNUNET_CONFIGURATION_Handle *cfg,
555 GNUNET_DV_ConnectCallback connect_cb,
556 GNUNET_DV_DistanceChangedCallback distance_cb,
557 GNUNET_DV_DisconnectCallback disconnect_cb,
558 GNUNET_DV_MessageReceivedCallback message_cb)
560 struct GNUNET_DV_ServiceHandle *sh;
562 sh = GNUNET_new (struct GNUNET_DV_ServiceHandle);
565 sh->connect_cb = connect_cb;
566 sh->distance_cb = distance_cb;
567 sh->disconnect_cb = disconnect_cb;
568 sh->message_cb = message_cb;
569 sh->peers = GNUNET_CONTAINER_multipeermap_create (128, GNUNET_YES);
576 * Disconnect from DV service.
578 * @param sh service handle
581 GNUNET_DV_service_disconnect (struct GNUNET_DV_ServiceHandle *sh)
583 struct GNUNET_DV_TransmitHandle *pos;
589 GNUNET_CLIENT_notify_transmit_ready_cancel (sh->th);
592 while (NULL != (pos = sh->th_head))
594 GNUNET_CONTAINER_DLL_remove (sh->th_head,
599 if (NULL != sh->client)
601 GNUNET_CLIENT_disconnect (sh->client);
604 GNUNET_CONTAINER_multipeermap_iterate (sh->peers,
607 GNUNET_CONTAINER_multipeermap_destroy (sh->peers);
613 * Send a message via DV service.
615 * @param sh service handle
616 * @param target intended recpient
617 * @param msg message payload
618 * @param cb function to invoke when done
619 * @param cb_cls closure for @a cb
620 * @return handle to cancel the operation
622 struct GNUNET_DV_TransmitHandle *
623 GNUNET_DV_send (struct GNUNET_DV_ServiceHandle *sh,
624 const struct GNUNET_PeerIdentity *target,
625 const struct GNUNET_MessageHeader *msg,
626 GNUNET_DV_MessageSentCallback cb,
629 struct GNUNET_DV_TransmitHandle *th;
630 struct GNUNET_DV_SendMessage *sm;
631 struct ConnectedPeer *peer;
633 if (ntohs (msg->size) + sizeof (struct GNUNET_DV_SendMessage) >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
638 LOG (GNUNET_ERROR_TYPE_DEBUG,
639 "Asked to send %u bytes of type %u to %s\n",
640 (unsigned int) msg->size,
641 (unsigned int) msg->type,
642 GNUNET_i2s (target));
643 peer = GNUNET_CONTAINER_multipeermap_get (sh->peers,
650 th = GNUNET_malloc (sizeof (struct GNUNET_DV_TransmitHandle) +
651 sizeof (struct GNUNET_DV_SendMessage) +
657 th->msg = (const struct GNUNET_MessageHeader *) &th[1];
658 sm = (struct GNUNET_DV_SendMessage *) &th[1];
659 sm->header.type = htons (GNUNET_MESSAGE_TYPE_DV_SEND);
660 sm->header.size = htons (sizeof (struct GNUNET_DV_SendMessage) +
662 if (0 == sh->uid_gen)
664 th->uid = sh->uid_gen;
665 sm->uid = htonl (sh->uid_gen++);
666 /* use memcpy here as 'target' may not be sufficiently aligned */
667 memcpy (&sm->target, target, sizeof (struct GNUNET_PeerIdentity));
668 memcpy (&sm[1], msg, ntohs (msg->size));
669 GNUNET_CONTAINER_DLL_insert (sh->th_head,
678 * Abort send operation (naturally, the message may have
679 * already been transmitted; this only stops the 'cb'
680 * from being called again).
682 * @param th send operation to cancel
685 GNUNET_DV_send_cancel (struct GNUNET_DV_TransmitHandle *th)
687 struct GNUNET_DV_ServiceHandle *sh = th->sh;
690 GNUNET_CONTAINER_DLL_remove (th->target->head,
694 GNUNET_CONTAINER_DLL_remove (sh->th_head,
701 /* end of dv_api.c */