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22 * @file fs/gnunet-service-fs_cadet_client.c
23 * @brief non-anonymous file-transfer
24 * @author Christian Grothoff
27 * - PORT is set to old application type, unsure if we should keep
28 * it that way (fine for now)
31 #include "gnunet_constants.h"
32 #include "gnunet_util_lib.h"
33 #include "gnunet_cadet_service.h"
34 #include "gnunet_protocols.h"
35 #include "gnunet_applications.h"
36 #include "gnunet-service-fs.h"
37 #include "gnunet-service-fs_indexing.h"
38 #include "gnunet-service-fs_cadet.h"
42 * After how long do we reset connections without replies?
44 #define CLIENT_RETRY_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)
48 * Handle for a cadet to another peer.
54 * Handle for a request that is going out via cadet API.
56 struct GSF_CadetRequest
62 struct GSF_CadetRequest *next;
67 struct GSF_CadetRequest *prev;
70 * Which cadet is this request associated with?
72 struct CadetHandle *mh;
75 * Function to call with the result.
77 GSF_CadetReplyProcessor proc;
85 * Query to transmit to the other peer.
87 struct GNUNET_HashCode query;
90 * Desired type for the reply.
92 enum GNUNET_BLOCK_Type type;
95 * Did we transmit this request already? #GNUNET_YES if we are
96 * in the 'waiting_map', #GNUNET_NO if we are in the 'pending' DLL.
103 * Handle for a cadet to another peer.
108 * Head of DLL of pending requests on this cadet.
110 struct GSF_CadetRequest *pending_head;
113 * Tail of DLL of pending requests on this cadet.
115 struct GSF_CadetRequest *pending_tail;
118 * Map from query to `struct GSF_CadetRequest`s waiting for
121 struct GNUNET_CONTAINER_MultiHashMap *waiting_map;
124 * Channel to the other peer.
126 struct GNUNET_CADET_Channel *channel;
129 * Handle for active write operation, or NULL.
131 struct GNUNET_CADET_TransmitHandle *wh;
134 * Which peer does this cadet go to?
136 struct GNUNET_PeerIdentity target;
139 * Task to kill inactive cadets (we keep them around for
140 * a few seconds to give the application a chance to give
143 struct GNUNET_SCHEDULER_Task * timeout_task;
146 * Task to reset cadets that had errors (asynchronously,
147 * as we may not be able to do it immediately during a
148 * callback from the cadet API).
150 struct GNUNET_SCHEDULER_Task * reset_task;
156 * Cadet channel for creating outbound channels.
158 static struct GNUNET_CADET_Handle *cadet_handle;
161 * Map from peer identities to 'struct CadetHandles' with cadet
162 * channels to those peers.
164 static struct GNUNET_CONTAINER_MultiPeerMap *cadet_map;
167 /* ********************* client-side code ************************* */
171 * Transmit pending requests via the cadet.
173 * @param mh cadet to process
176 transmit_pending (struct CadetHandle *mh);
180 * Iterator called on each entry in a waiting map to
181 * move it back to the pending list.
183 * @param cls the `struct CadetHandle`
184 * @param key the key of the entry in the map (the query)
185 * @param value the `struct GSF_CadetRequest` to move to pending
186 * @return #GNUNET_YES (continue to iterate)
189 move_to_pending (void *cls,
190 const struct GNUNET_HashCode *key,
193 struct CadetHandle *mh = cls;
194 struct GSF_CadetRequest *sr = value;
196 GNUNET_assert (GNUNET_YES ==
197 GNUNET_CONTAINER_multihashmap_remove (mh->waiting_map,
200 GNUNET_CONTAINER_DLL_insert (mh->pending_head,
203 sr->was_transmitted = GNUNET_NO;
209 * We had a serious error, tear down and re-create cadet from scratch.
211 * @param mh cadet to reset
214 reset_cadet (struct CadetHandle *mh)
216 struct GNUNET_CADET_Channel *channel = mh->channel;
217 struct GNUNET_HashCode port;
219 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
220 "Resetting cadet channel to %s\n",
221 GNUNET_i2s (&mh->target));
229 GNUNET_CADET_notify_transmit_ready_cancel (mh->wh);
232 GNUNET_CADET_channel_destroy (channel);
234 GNUNET_CONTAINER_multihashmap_iterate (mh->waiting_map,
237 GNUNET_CRYPTO_hash (GNUNET_APPLICATION_PORT_FS_BLOCK_TRANSFER,
238 strlen (GNUNET_APPLICATION_PORT_FS_BLOCK_TRANSFER),
240 mh->channel = GNUNET_CADET_channel_create (cadet_handle,
244 GNUNET_CADET_OPTION_RELIABLE);
245 transmit_pending (mh);
250 * Task called when it is time to destroy an inactive cadet channel.
252 * @param cls the `struct CadetHandle` to tear down
255 cadet_timeout (void *cls)
257 struct CadetHandle *mh = cls;
258 struct GNUNET_CADET_Channel *tun;
260 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
261 "Timeout on cadet channel to %s\n",
262 GNUNET_i2s (&mh->target));
263 mh->timeout_task = NULL;
267 GNUNET_CADET_channel_destroy (tun);
272 * Task called when it is time to reset an cadet.
274 * @param cls the `struct CadetHandle` to tear down
277 reset_cadet_task (void *cls)
279 struct CadetHandle *mh = cls;
281 mh->reset_task = NULL;
287 * We had a serious error, tear down and re-create cadet from scratch,
288 * but do so asynchronously.
290 * @param mh cadet to reset
293 reset_cadet_async (struct CadetHandle *mh)
295 if (NULL != mh->reset_task)
296 GNUNET_SCHEDULER_cancel (mh->reset_task);
297 mh->reset_task = GNUNET_SCHEDULER_add_now (&reset_cadet_task,
303 * Functions of this signature are called whenever we are ready to transmit
306 * @param cls the struct CadetHandle for which we did the write call
307 * @param size the number of bytes that can be written to @a buf
308 * @param buf where to write the message
309 * @return number of bytes written to @a buf
312 transmit_sqm (void *cls,
316 struct CadetHandle *mh = cls;
317 struct CadetQueryMessage sqm;
318 struct GSF_CadetRequest *sr;
323 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
324 "Cadet channel to %s failed during transmission attempt, rebuilding\n",
325 GNUNET_i2s (&mh->target));
326 reset_cadet_async (mh);
329 sr = mh->pending_head;
332 GNUNET_assert (size >= sizeof (struct CadetQueryMessage));
333 GNUNET_CONTAINER_DLL_remove (mh->pending_head,
336 GNUNET_assert (GNUNET_OK ==
337 GNUNET_CONTAINER_multihashmap_put (mh->waiting_map,
340 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
341 sr->was_transmitted = GNUNET_YES;
342 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
343 "Sending query for %s via cadet to %s\n",
344 GNUNET_h2s (&sr->query),
345 GNUNET_i2s (&mh->target));
346 sqm.header.size = htons (sizeof (sqm));
347 sqm.header.type = htons (GNUNET_MESSAGE_TYPE_FS_CADET_QUERY);
348 sqm.type = htonl (sr->type);
349 sqm.query = sr->query;
350 GNUNET_memcpy (buf, &sqm, sizeof (sqm));
351 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
352 "Successfully transmitted %u bytes via cadet to %s\n",
354 GNUNET_i2s (&mh->target));
355 transmit_pending (mh);
361 * Transmit pending requests via the cadet.
363 * @param mh cadet to process
366 transmit_pending (struct CadetHandle *mh)
368 if (NULL == mh->channel)
372 mh->wh = GNUNET_CADET_notify_transmit_ready (mh->channel, GNUNET_YES /* allow cork */,
373 GNUNET_TIME_UNIT_FOREVER_REL,
374 sizeof (struct CadetQueryMessage),
380 * Closure for handle_reply().
382 struct HandleReplyClosure
391 * Expiration time for the block.
393 struct GNUNET_TIME_Absolute expiration;
396 * Number of bytes in 'data'.
403 enum GNUNET_BLOCK_Type type;
406 * Did we have a matching query?
413 * Iterator called on each entry in a waiting map to
416 * @param cls the `struct HandleReplyClosure`
417 * @param key the key of the entry in the map (the query)
418 * @param value the `struct GSF_CadetRequest` to handle result for
419 * @return #GNUNET_YES (continue to iterate)
422 handle_reply (void *cls,
423 const struct GNUNET_HashCode *key,
426 struct HandleReplyClosure *hrc = cls;
427 struct GSF_CadetRequest *sr = value;
429 sr->proc (sr->proc_cls,
435 GSF_cadet_query_cancel (sr);
436 hrc->found = GNUNET_YES;
442 * Functions with this signature are called whenever a complete reply
445 * @param cls closure with the `struct CadetHandle`
446 * @param channel channel handle
447 * @param channel_ctx channel context
448 * @param message the actual message
449 * @return #GNUNET_OK on success, #GNUNET_SYSERR to stop further processing
453 struct GNUNET_CADET_Channel *channel,
455 const struct GNUNET_MessageHeader *message)
457 struct CadetHandle *mh = *channel_ctx;
458 const struct CadetReplyMessage *srm;
459 struct HandleReplyClosure hrc;
461 enum GNUNET_BLOCK_Type type;
462 struct GNUNET_HashCode query;
464 msize = ntohs (message->size);
465 if (sizeof (struct CadetReplyMessage) > msize)
468 reset_cadet_async (mh);
469 return GNUNET_SYSERR;
471 srm = (const struct CadetReplyMessage *) message;
472 msize -= sizeof (struct CadetReplyMessage);
473 type = (enum GNUNET_BLOCK_Type) ntohl (srm->type);
475 GNUNET_BLOCK_get_key (GSF_block_ctx,
477 &srm[1], msize, &query))
480 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
481 "Received bogus reply of type %u with %u bytes via cadet from peer %s\n",
484 GNUNET_i2s (&mh->target));
485 reset_cadet_async (mh);
486 return GNUNET_SYSERR;
488 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
489 "Received reply `%s' via cadet from peer %s\n",
491 GNUNET_i2s (&mh->target));
492 GNUNET_CADET_receive_done (channel);
493 GNUNET_STATISTICS_update (GSF_stats,
494 gettext_noop ("# replies received via cadet"), 1,
497 hrc.data_size = msize;
498 hrc.expiration = GNUNET_TIME_absolute_ntoh (srm->expiration);
500 hrc.found = GNUNET_NO;
501 GNUNET_CONTAINER_multihashmap_get_multiple (mh->waiting_map,
505 if (GNUNET_NO == hrc.found)
507 GNUNET_STATISTICS_update (GSF_stats,
508 gettext_noop ("# replies received via cadet dropped"), 1,
517 * Get (or create) a cadet to talk to the given peer.
519 * @param target peer we want to communicate with
521 static struct CadetHandle *
522 get_cadet (const struct GNUNET_PeerIdentity *target)
524 struct CadetHandle *mh;
525 struct GNUNET_HashCode port;
527 mh = GNUNET_CONTAINER_multipeermap_get (cadet_map,
531 if (NULL != mh->timeout_task)
533 GNUNET_SCHEDULER_cancel (mh->timeout_task);
534 mh->timeout_task = NULL;
538 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
539 "Creating cadet channel to %s\n",
540 GNUNET_i2s (target));
541 mh = GNUNET_new (struct CadetHandle);
542 mh->reset_task = GNUNET_SCHEDULER_add_delayed (CLIENT_RETRY_TIMEOUT,
545 mh->waiting_map = GNUNET_CONTAINER_multihashmap_create (16, GNUNET_YES);
546 mh->target = *target;
547 GNUNET_assert (GNUNET_OK ==
548 GNUNET_CONTAINER_multipeermap_put (cadet_map,
551 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
552 GNUNET_CRYPTO_hash (GNUNET_APPLICATION_PORT_FS_BLOCK_TRANSFER,
553 strlen (GNUNET_APPLICATION_PORT_FS_BLOCK_TRANSFER),
555 mh->channel = GNUNET_CADET_channel_create (cadet_handle,
559 GNUNET_CADET_OPTION_RELIABLE);
561 GNUNET_CONTAINER_multipeermap_get (cadet_map,
568 * Look for a block by directly contacting a particular peer.
570 * @param target peer that should have the block
571 * @param query hash to query for the block
572 * @param type desired type for the block
573 * @param proc function to call with result
574 * @param proc_cls closure for @a proc
575 * @return handle to cancel the operation
577 struct GSF_CadetRequest *
578 GSF_cadet_query (const struct GNUNET_PeerIdentity *target,
579 const struct GNUNET_HashCode *query,
580 enum GNUNET_BLOCK_Type type,
581 GSF_CadetReplyProcessor proc, void *proc_cls)
583 struct CadetHandle *mh;
584 struct GSF_CadetRequest *sr;
586 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
587 "Preparing to send query for %s via cadet to %s\n",
589 GNUNET_i2s (target));
590 mh = get_cadet (target);
591 sr = GNUNET_new (struct GSF_CadetRequest);
594 sr->proc_cls = proc_cls;
597 GNUNET_CONTAINER_DLL_insert (mh->pending_head,
600 transmit_pending (mh);
606 * Cancel an active request; must not be called after 'proc'
609 * @param sr request to cancel
612 GSF_cadet_query_cancel (struct GSF_CadetRequest *sr)
614 struct CadetHandle *mh = sr->mh;
615 GSF_CadetReplyProcessor p;
621 /* signal failure / cancellation to callback */
622 p (sr->proc_cls, GNUNET_BLOCK_TYPE_ANY,
623 GNUNET_TIME_UNIT_ZERO_ABS,
626 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
627 "Cancelled query for %s via cadet to %s\n",
628 GNUNET_h2s (&sr->query),
629 GNUNET_i2s (&sr->mh->target));
630 if (GNUNET_YES == sr->was_transmitted)
631 GNUNET_assert (GNUNET_OK ==
632 GNUNET_CONTAINER_multihashmap_remove (mh->waiting_map,
636 GNUNET_CONTAINER_DLL_remove (mh->pending_head,
640 if ( (0 == GNUNET_CONTAINER_multihashmap_size (mh->waiting_map)) &&
641 (NULL == mh->pending_head) )
642 mh->timeout_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
649 * Iterator called on each entry in a waiting map to
650 * call the 'proc' continuation and release associated
653 * @param cls the `struct CadetHandle`
654 * @param key the key of the entry in the map (the query)
655 * @param value the `struct GSF_CadetRequest` to clean up
656 * @return #GNUNET_YES (continue to iterate)
659 free_waiting_entry (void *cls,
660 const struct GNUNET_HashCode *key,
663 struct GSF_CadetRequest *sr = value;
665 GSF_cadet_query_cancel (sr);
671 * Function called by cadet when a client disconnects.
672 * Cleans up our `struct CadetClient` of that channel.
675 * @param channel channel of the disconnecting client
676 * @param channel_ctx our `struct CadetClient`
679 cleaner_cb (void *cls,
680 const struct GNUNET_CADET_Channel *channel,
683 struct CadetHandle *mh = channel_ctx;
684 struct GSF_CadetRequest *sr;
686 if (NULL == mh->channel)
687 return; /* being destroyed elsewhere */
688 GNUNET_assert (channel == mh->channel);
690 while (NULL != (sr = mh->pending_head))
691 GSF_cadet_query_cancel (sr);
692 /* first remove `mh` from the `cadet_map`, so that if the
693 callback from `free_waiting_entry()` happens to re-issue
694 the request, we don't immediately have it back in the
696 GNUNET_assert (GNUNET_OK ==
697 GNUNET_CONTAINER_multipeermap_remove (cadet_map,
700 GNUNET_CONTAINER_multihashmap_iterate (mh->waiting_map,
704 GNUNET_CADET_notify_transmit_ready_cancel (mh->wh);
705 if (NULL != mh->timeout_task)
706 GNUNET_SCHEDULER_cancel (mh->timeout_task);
707 if (NULL != mh->reset_task)
708 GNUNET_SCHEDULER_cancel (mh->reset_task);
710 GNUNET_CONTAINER_multihashmap_size (mh->waiting_map));
711 GNUNET_CONTAINER_multihashmap_destroy (mh->waiting_map);
717 * Initialize subsystem for non-anonymous file-sharing.
720 GSF_cadet_start_client ()
722 static const struct GNUNET_CADET_MessageHandler handlers[] = {
723 { &reply_cb, GNUNET_MESSAGE_TYPE_FS_CADET_REPLY, 0 },
727 cadet_map = GNUNET_CONTAINER_multipeermap_create (16, GNUNET_YES);
728 cadet_handle = GNUNET_CADET_connect (GSF_cfg,
736 * Function called on each active cadets to shut them down.
739 * @param key target peer, unused
740 * @param value the `struct CadetHandle` to destroy
741 * @return #GNUNET_YES (continue to iterate)
744 release_cadets (void *cls,
745 const struct GNUNET_PeerIdentity *key,
748 struct CadetHandle *mh = value;
750 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
751 "Timeout on cadet channel to %s\n",
752 GNUNET_i2s (&mh->target));
753 if (NULL != mh->channel)
754 GNUNET_CADET_channel_destroy (mh->channel);
760 * Shutdown subsystem for non-anonymous file-sharing.
763 GSF_cadet_stop_client ()
765 GNUNET_CONTAINER_multipeermap_iterate (cadet_map,
768 GNUNET_CONTAINER_multipeermap_destroy (cadet_map);
770 if (NULL != cadet_handle)
772 GNUNET_CADET_disconnect (cadet_handle);
778 /* end of gnunet-service-fs_cadet_client.c */