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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;
218 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
219 "Resetting cadet channel to %s\n",
220 GNUNET_i2s (&mh->target));
228 GNUNET_CADET_notify_transmit_ready_cancel (mh->wh);
231 GNUNET_CADET_channel_destroy (channel);
233 GNUNET_CONTAINER_multihashmap_iterate (mh->waiting_map,
236 mh->channel = GNUNET_CADET_channel_create (cadet_handle,
239 GNUNET_APPLICATION_TYPE_FS_BLOCK_TRANSFER,
240 GNUNET_CADET_OPTION_RELIABLE);
241 transmit_pending (mh);
246 * Task called when it is time to destroy an inactive cadet channel.
248 * @param cls the `struct CadetHandle` to tear down
249 * @param tc scheduler context, unused
252 cadet_timeout (void *cls,
253 const struct GNUNET_SCHEDULER_TaskContext *tc)
255 struct CadetHandle *mh = cls;
256 struct GNUNET_CADET_Channel *tun;
258 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
259 "Timeout on cadet channel to %s\n",
260 GNUNET_i2s (&mh->target));
261 mh->timeout_task = NULL;
265 GNUNET_CADET_channel_destroy (tun);
270 * Task called when it is time to reset an cadet.
272 * @param cls the `struct CadetHandle` to tear down
273 * @param tc scheduler context, unused
276 reset_cadet_task (void *cls,
277 const struct GNUNET_SCHEDULER_TaskContext *tc)
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 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;
526 mh = GNUNET_CONTAINER_multipeermap_get (cadet_map,
530 if (NULL != mh->timeout_task)
532 GNUNET_SCHEDULER_cancel (mh->timeout_task);
533 mh->timeout_task = NULL;
537 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
538 "Creating cadet channel to %s\n",
539 GNUNET_i2s (target));
540 mh = GNUNET_new (struct CadetHandle);
541 mh->reset_task = GNUNET_SCHEDULER_add_delayed (CLIENT_RETRY_TIMEOUT,
544 mh->waiting_map = GNUNET_CONTAINER_multihashmap_create (16, GNUNET_YES);
545 mh->target = *target;
546 GNUNET_assert (GNUNET_OK ==
547 GNUNET_CONTAINER_multipeermap_put (cadet_map,
550 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
551 mh->channel = GNUNET_CADET_channel_create (cadet_handle,
554 GNUNET_APPLICATION_TYPE_FS_BLOCK_TRANSFER,
555 GNUNET_CADET_OPTION_RELIABLE);
557 GNUNET_CONTAINER_multipeermap_get (cadet_map,
564 * Look for a block by directly contacting a particular peer.
566 * @param target peer that should have the block
567 * @param query hash to query for the block
568 * @param type desired type for the block
569 * @param proc function to call with result
570 * @param proc_cls closure for @a proc
571 * @return handle to cancel the operation
573 struct GSF_CadetRequest *
574 GSF_cadet_query (const struct GNUNET_PeerIdentity *target,
575 const struct GNUNET_HashCode *query,
576 enum GNUNET_BLOCK_Type type,
577 GSF_CadetReplyProcessor proc, void *proc_cls)
579 struct CadetHandle *mh;
580 struct GSF_CadetRequest *sr;
582 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
583 "Preparing to send query for %s via cadet to %s\n",
585 GNUNET_i2s (target));
586 mh = get_cadet (target);
587 sr = GNUNET_new (struct GSF_CadetRequest);
590 sr->proc_cls = proc_cls;
593 GNUNET_CONTAINER_DLL_insert (mh->pending_head,
596 transmit_pending (mh);
602 * Cancel an active request; must not be called after 'proc'
605 * @param sr request to cancel
608 GSF_cadet_query_cancel (struct GSF_CadetRequest *sr)
610 struct CadetHandle *mh = sr->mh;
611 GSF_CadetReplyProcessor p;
617 /* signal failure / cancellation to callback */
618 p (sr->proc_cls, GNUNET_BLOCK_TYPE_ANY,
619 GNUNET_TIME_UNIT_ZERO_ABS,
622 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
623 "Cancelled query for %s via cadet to %s\n",
624 GNUNET_h2s (&sr->query),
625 GNUNET_i2s (&sr->mh->target));
626 if (GNUNET_YES == sr->was_transmitted)
627 GNUNET_assert (GNUNET_OK ==
628 GNUNET_CONTAINER_multihashmap_remove (mh->waiting_map,
632 GNUNET_CONTAINER_DLL_remove (mh->pending_head,
636 if ( (0 == GNUNET_CONTAINER_multihashmap_size (mh->waiting_map)) &&
637 (NULL == mh->pending_head) )
638 mh->timeout_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
645 * Iterator called on each entry in a waiting map to
646 * call the 'proc' continuation and release associated
649 * @param cls the `struct CadetHandle`
650 * @param key the key of the entry in the map (the query)
651 * @param value the `struct GSF_CadetRequest` to clean up
652 * @return #GNUNET_YES (continue to iterate)
655 free_waiting_entry (void *cls,
656 const struct GNUNET_HashCode *key,
659 struct GSF_CadetRequest *sr = value;
661 GSF_cadet_query_cancel (sr);
667 * Function called by cadet when a client disconnects.
668 * Cleans up our `struct CadetClient` of that channel.
671 * @param channel channel of the disconnecting client
672 * @param channel_ctx our `struct CadetClient`
675 cleaner_cb (void *cls,
676 const struct GNUNET_CADET_Channel *channel,
679 struct CadetHandle *mh = channel_ctx;
680 struct GSF_CadetRequest *sr;
682 if (NULL == mh->channel)
683 return; /* being destroyed elsewhere */
684 GNUNET_assert (channel == mh->channel);
686 while (NULL != (sr = mh->pending_head))
687 GSF_cadet_query_cancel (sr);
688 /* first remove `mh` from the `cadet_map`, so that if the
689 callback from `free_waiting_entry()` happens to re-issue
690 the request, we don't immediately have it back in the
692 GNUNET_assert (GNUNET_OK ==
693 GNUNET_CONTAINER_multipeermap_remove (cadet_map,
696 GNUNET_CONTAINER_multihashmap_iterate (mh->waiting_map,
700 GNUNET_CADET_notify_transmit_ready_cancel (mh->wh);
701 if (NULL != mh->timeout_task)
702 GNUNET_SCHEDULER_cancel (mh->timeout_task);
703 if (NULL != mh->reset_task)
704 GNUNET_SCHEDULER_cancel (mh->reset_task);
706 GNUNET_CONTAINER_multihashmap_size (mh->waiting_map));
707 GNUNET_CONTAINER_multihashmap_destroy (mh->waiting_map);
713 * Initialize subsystem for non-anonymous file-sharing.
716 GSF_cadet_start_client ()
718 static const struct GNUNET_CADET_MessageHandler handlers[] = {
719 { &reply_cb, GNUNET_MESSAGE_TYPE_FS_CADET_REPLY, 0 },
723 cadet_map = GNUNET_CONTAINER_multipeermap_create (16, GNUNET_YES);
724 cadet_handle = GNUNET_CADET_connect (GSF_cfg,
734 * Function called on each active cadets to shut them down.
737 * @param key target peer, unused
738 * @param value the `struct CadetHandle` to destroy
739 * @return #GNUNET_YES (continue to iterate)
742 release_cadets (void *cls,
743 const struct GNUNET_PeerIdentity *key,
746 struct CadetHandle *mh = value;
748 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
749 "Timeout on cadet channel to %s\n",
750 GNUNET_i2s (&mh->target));
751 if (NULL != mh->channel)
752 GNUNET_CADET_channel_destroy (mh->channel);
758 * Shutdown subsystem for non-anonymous file-sharing.
761 GSF_cadet_stop_client ()
763 GNUNET_CONTAINER_multipeermap_iterate (cadet_map,
766 GNUNET_CONTAINER_multipeermap_destroy (cadet_map);
768 if (NULL != cadet_handle)
770 GNUNET_CADET_disconnect (cadet_handle);
776 /* end of gnunet-service-fs_cadet_client.c */