2 This file is part of GNUnet.
3 (C) 2009, 2010, 2011 Christian Grothoff (and other contributing authors)
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6 it under the terms of the GNU General Public License as published
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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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22 * @file dht/gnunet-service-dht_clients.c
23 * @brief GNUnet DHT service's client management code
24 * @author Christian Grothoff
25 * @author Nathan Evans
29 #include "gnunet_constants.h"
30 #include "gnunet_protocols.h"
31 #include "gnunet_statistics_service.h"
32 #include "gnunet-service-dht.h"
33 #include "gnunet-service-dht_clients.h"
34 #include "gnunet-service-dht_datacache.h"
35 #include "gnunet-service-dht_neighbours.h"
40 * Should routing details be logged to stderr (for debugging)?
42 #define LOG_ROUTE_DETAILS_STDERR GNUNET_NO
46 * Linked list of messages to send to clients.
51 * Pointer to next item in the list
53 struct PendingMessage *next;
56 * Pointer to previous item in the list
58 struct PendingMessage *prev;
61 * Actual message to be sent, allocated at the end of the struct:
62 * // msg = (cast) &pm[1];
63 * // memcpy (&pm[1], data, len);
65 const struct GNUNET_MessageHeader *msg;
71 * Struct containing information about a client,
72 * handle to connect to it, and any pending messages
73 * that need to be sent to it.
78 * Linked list of active clients
80 struct ClientList *next;
83 * Linked list of active clients
85 struct ClientList *prev;
88 * The handle to this client
90 struct GNUNET_SERVER_Client *client_handle;
93 * Handle to the current transmission request, NULL
96 struct GNUNET_SERVER_TransmitHandle *transmit_handle;
99 * Linked list of pending messages for this client
101 struct PendingMessage *pending_head;
104 * Tail of linked list of pending messages for this client
106 struct PendingMessage *pending_tail;
112 * Entry in the DHT routing table for a client's GET request.
114 struct ClientQueryRecord
118 * The key this request was about
120 struct GNUNET_HashCode key;
123 * Client responsible for the request.
125 struct ClientList *client;
128 * Extended query (see gnunet_block_lib.h), allocated at the end of this struct.
133 * Replies we have already seen for this request.
135 struct GNUNET_HashCode *seen_replies;
138 * Pointer to this nodes heap location in the retry-heap (for fast removal)
140 struct GNUNET_CONTAINER_HeapNode *hnode;
143 * What's the delay between re-try operations that we currently use for this
146 struct GNUNET_TIME_Relative retry_frequency;
149 * What's the next time we should re-try this request?
151 struct GNUNET_TIME_Absolute retry_time;
154 * The unique identifier of this request
159 * Number of bytes in xquery.
164 * Number of entries in 'seen_replies'.
166 unsigned int seen_replies_count;
169 * Desired replication level
171 uint32_t replication;
174 * Any message options for this request
176 uint32_t msg_options;
179 * The type for the data for the GET request.
181 enum GNUNET_BLOCK_Type type;
187 * Struct containing paremeters of monitoring requests.
189 struct ClientMonitorRecord
193 * Next element in DLL.
195 struct ClientMonitorRecord *next;
198 * Previous element in DLL.
200 struct ClientMonitorRecord *prev;
203 * Type of blocks that are of interest
205 enum GNUNET_BLOCK_Type type;
208 * Key of data of interest, NULL for all.
210 struct GNUNET_HashCode *key;
213 * Flag whether to notify about GET messages.
218 * Flag whether to notify about GET_REPONSE messages.
223 * Flag whether to notify about PUT messages.
228 * Client to notify of these requests.
230 struct ClientList *client;
235 * List of active clients.
237 static struct ClientList *client_head;
240 * List of active clients.
242 static struct ClientList *client_tail;
245 * List of active monitoring requests.
247 static struct ClientMonitorRecord *monitor_head;
250 * List of active monitoring requests.
252 static struct ClientMonitorRecord *monitor_tail;
255 * Hashmap for fast key based lookup, maps keys to 'struct ClientQueryRecord' entries.
257 static struct GNUNET_CONTAINER_MultiHashMap *forward_map;
260 * Heap with all of our client's request, sorted by retry time (earliest on top).
262 static struct GNUNET_CONTAINER_Heap *retry_heap;
265 * Task that re-transmits requests (using retry_heap).
267 static GNUNET_SCHEDULER_TaskIdentifier retry_task;
271 * Task run to check for messages that need to be sent to a client.
273 * @param client a ClientList, containing the client and any messages to be sent to it
276 process_pending_messages (struct ClientList *client);
280 * Add a PendingMessage to the clients list of messages to be sent
282 * @param client the active client to send the message to
283 * @param pending_message the actual message to send
286 add_pending_message (struct ClientList *client,
287 struct PendingMessage *pending_message)
289 GNUNET_CONTAINER_DLL_insert_tail (client->pending_head, client->pending_tail,
291 process_pending_messages (client);
296 * Find a client if it exists, add it otherwise.
298 * @param client the server handle to the client
300 * @return the client if found, a new client otherwise
302 static struct ClientList *
303 find_active_client (struct GNUNET_SERVER_Client *client)
305 struct ClientList *pos = client_head;
306 struct ClientList *ret;
310 if (pos->client_handle == client)
314 ret = GNUNET_malloc (sizeof (struct ClientList));
315 ret->client_handle = client;
316 GNUNET_CONTAINER_DLL_insert (client_head, client_tail, ret);
322 * Iterator over hash map entries that frees all entries
323 * associated with the given client.
325 * @param cls client to search for in source routes
326 * @param key current key code (ignored)
327 * @param value value in the hash map, a ClientQueryRecord
328 * @return GNUNET_YES (we should continue to iterate)
331 remove_client_records (void *cls, const struct GNUNET_HashCode * key, void *value)
333 struct ClientList *client = cls;
334 struct ClientQueryRecord *record = value;
336 if (record->client != client)
338 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
339 "Removing client %p's record for key %s\n", client,
341 GNUNET_assert (GNUNET_YES ==
342 GNUNET_CONTAINER_multihashmap_remove (forward_map, key,
344 if (NULL != record->hnode)
345 GNUNET_CONTAINER_heap_remove_node (record->hnode);
346 GNUNET_array_grow (record->seen_replies, record->seen_replies_count, 0);
347 GNUNET_free (record);
353 * Functions with this signature are called whenever a client
354 * is disconnected on the network level.
356 * @param cls closure (NULL for dht)
357 * @param client identification of the client; NULL
358 * for the last call when the server is destroyed
361 handle_client_disconnect (void *cls, struct GNUNET_SERVER_Client *client)
363 struct ClientList *pos;
364 struct PendingMessage *reply;
365 struct ClientMonitorRecord *monitor;
367 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Local client %p disconnects\n", client);
368 pos = find_active_client (client);
369 GNUNET_CONTAINER_DLL_remove (client_head, client_tail, pos);
370 if (pos->transmit_handle != NULL)
371 GNUNET_SERVER_notify_transmit_ready_cancel (pos->transmit_handle);
372 while (NULL != (reply = pos->pending_head))
374 GNUNET_CONTAINER_DLL_remove (pos->pending_head, pos->pending_tail, reply);
377 monitor = monitor_head;
378 while (NULL != monitor)
380 if (monitor->client == pos)
382 struct ClientMonitorRecord *next;
384 GNUNET_free_non_null (monitor->key);
385 next = monitor->next;
386 GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, monitor);
387 GNUNET_free (monitor);
391 monitor = monitor->next;
393 GNUNET_CONTAINER_multihashmap_iterate (forward_map, &remove_client_records,
400 * Route the given request via the DHT. This includes updating
401 * the bloom filter and retransmission times, building the P2P
402 * message and initiating the routing operation.
405 transmit_request (struct ClientQueryRecord *cqr)
407 int32_t reply_bf_mutator;
408 struct GNUNET_CONTAINER_BloomFilter *reply_bf;
409 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
411 GNUNET_STATISTICS_update (GDS_stats,
413 ("# GET requests from clients injected"), 1,
416 (int32_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
419 GNUNET_BLOCK_construct_bloomfilter (reply_bf_mutator, cqr->seen_replies,
420 cqr->seen_replies_count);
422 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
423 GNUNET_CONSTANTS_BLOOMFILTER_K);
424 GDS_NEIGHBOURS_handle_get (cqr->type, cqr->msg_options, cqr->replication,
426 &cqr->key, cqr->xquery, cqr->xquery_size, reply_bf,
427 reply_bf_mutator, peer_bf);
428 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
429 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
431 /* exponential back-off for retries, max 1h */
432 cqr->retry_frequency = GNUNET_TIME_STD_BACKOFF (cqr->retry_frequency);
433 cqr->retry_time = GNUNET_TIME_relative_to_absolute (cqr->retry_frequency);
438 * Task that looks at the 'retry_heap' and transmits all of the requests
439 * on the heap that are ready for transmission. Then re-schedules
440 * itself (unless the heap is empty).
443 * @param tc scheduler context
446 transmit_next_request_task (void *cls,
447 const struct GNUNET_SCHEDULER_TaskContext *tc)
449 struct ClientQueryRecord *cqr;
450 struct GNUNET_TIME_Relative delay;
452 retry_task = GNUNET_SCHEDULER_NO_TASK;
453 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
455 while (NULL != (cqr = GNUNET_CONTAINER_heap_remove_root (retry_heap)))
458 delay = GNUNET_TIME_absolute_get_remaining (cqr->retry_time);
459 if (delay.rel_value > 0)
462 GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
463 cqr->retry_time.abs_value);
465 GNUNET_SCHEDULER_add_delayed (delay, &transmit_next_request_task,
469 transmit_request (cqr);
471 GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
472 cqr->retry_time.abs_value);
478 * Handler for PUT messages.
480 * @param cls closure for the service
481 * @param client the client we received this message from
482 * @param message the actual message received
485 handle_dht_local_put (void *cls, struct GNUNET_SERVER_Client *client,
486 const struct GNUNET_MessageHeader *message)
488 const struct GNUNET_DHT_ClientPutMessage *dht_msg;
489 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
491 struct PendingMessage *pm;
492 struct GNUNET_DHT_ClientPutConfirmationMessage *conf;
494 size = ntohs (message->size);
495 if (size < sizeof (struct GNUNET_DHT_ClientPutMessage))
498 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
501 GNUNET_STATISTICS_update (GDS_stats,
503 ("# PUT requests received from clients"), 1,
505 dht_msg = (const struct GNUNET_DHT_ClientPutMessage *) message;
506 /* give to local clients */
507 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
508 "Handling local PUT of %u-bytes for query %s\n",
509 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
510 GNUNET_h2s (&dht_msg->key));
511 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
512 &dht_msg->key, 0, NULL, 0, NULL,
513 ntohl (dht_msg->type),
514 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
517 GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
518 &dht_msg->key, 0, NULL, ntohl (dht_msg->type),
519 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
521 /* route to other peers */
523 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
524 GNUNET_CONSTANTS_BLOOMFILTER_K);
525 GDS_NEIGHBOURS_handle_put (ntohl (dht_msg->type), ntohl (dht_msg->options),
526 ntohl (dht_msg->desired_replication_level),
527 GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
529 peer_bf, &dht_msg->key, 0, NULL, &dht_msg[1],
531 sizeof (struct GNUNET_DHT_ClientPutMessage));
532 GDS_CLIENTS_process_put (ntohl (dht_msg->options),
533 ntohl (dht_msg->type),
535 ntohl (dht_msg->desired_replication_level),
537 GDS_NEIGHBOURS_get_id(),
538 GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
541 size - sizeof (struct GNUNET_DHT_ClientPutMessage));
542 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
543 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
544 sizeof (struct GNUNET_DHT_ClientPutConfirmationMessage));
545 conf = (struct GNUNET_DHT_ClientPutConfirmationMessage *) &pm[1];
546 conf->header.size = htons (sizeof (struct GNUNET_DHT_ClientPutConfirmationMessage));
547 conf->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_CLIENT_PUT_OK);
548 conf->reserved = htonl (0);
549 conf->unique_id = dht_msg->unique_id;
550 pm->msg = &conf->header;
551 add_pending_message (find_active_client (client), pm);
552 GNUNET_SERVER_receive_done (client, GNUNET_OK);
557 * Handler for DHT GET messages from the client.
559 * @param cls closure for the service
560 * @param client the client we received this message from
561 * @param message the actual message received
564 handle_dht_local_get (void *cls, struct GNUNET_SERVER_Client *client,
565 const struct GNUNET_MessageHeader *message)
567 const struct GNUNET_DHT_ClientGetMessage *get;
568 struct ClientQueryRecord *cqr;
573 size = ntohs (message->size);
574 if (size < sizeof (struct GNUNET_DHT_ClientGetMessage))
577 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
580 xquery_size = size - sizeof (struct GNUNET_DHT_ClientGetMessage);
581 get = (const struct GNUNET_DHT_ClientGetMessage *) message;
582 xquery = (const char *) &get[1];
583 GNUNET_STATISTICS_update (GDS_stats,
585 ("# GET requests received from clients"), 1,
587 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
588 "Received request for %s from local client %p\n",
589 GNUNET_h2s (&get->key), client);
591 if (LOG_ROUTE_DETAILS_STDERR)
594 "XDHT CLIENT-GET %s @ %u\n",
595 GNUNET_h2s (&get->key),
600 cqr = GNUNET_malloc (sizeof (struct ClientQueryRecord) + xquery_size);
602 cqr->client = find_active_client (client);
603 cqr->xquery = (void *) &cqr[1];
604 memcpy (&cqr[1], xquery, xquery_size);
605 cqr->hnode = GNUNET_CONTAINER_heap_insert (retry_heap, cqr, 0);
606 cqr->retry_frequency = GNUNET_TIME_UNIT_SECONDS;
607 cqr->retry_time = GNUNET_TIME_absolute_get ();
608 cqr->unique_id = get->unique_id;
609 cqr->xquery_size = xquery_size;
610 cqr->replication = ntohl (get->desired_replication_level);
611 cqr->msg_options = ntohl (get->options);
612 cqr->type = ntohl (get->type);
613 // FIXME use cqr->key, set multihashmap create to GNUNET_YES
614 GNUNET_CONTAINER_multihashmap_put (forward_map, &get->key, cqr,
615 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
616 GDS_CLIENTS_process_get (ntohl (get->options),
619 ntohl (get->desired_replication_level),
621 GDS_NEIGHBOURS_get_id(),
623 /* start remote requests */
624 if (GNUNET_SCHEDULER_NO_TASK != retry_task)
625 GNUNET_SCHEDULER_cancel (retry_task);
626 retry_task = GNUNET_SCHEDULER_add_now (&transmit_next_request_task, NULL);
627 /* perform local lookup */
628 GDS_DATACACHE_handle_get (&get->key, cqr->type, cqr->xquery, xquery_size,
630 GNUNET_SERVER_receive_done (client, GNUNET_OK);
635 * Closure for 'find_by_unique_id'.
637 struct FindByUniqueIdContext
640 * Where to store the result, if found.
642 struct ClientQueryRecord *cqr;
649 * Function called for each existing DHT record for the given
650 * query. Checks if it matches the UID given in the closure
651 * and if so returns the entry as a result.
653 * @param cls the search context
654 * @param key query for the lookup (not used)
655 * @param value the 'struct ClientQueryRecord'
656 * @return GNUNET_YES to continue iteration (result not yet found)
659 find_by_unique_id (void *cls,
660 const struct GNUNET_HashCode *key,
663 struct FindByUniqueIdContext *fui_ctx = cls;
664 struct ClientQueryRecord *cqr = value;
666 if (cqr->unique_id != fui_ctx->unique_id)
674 * Handler for "GET result seen" messages from the client.
676 * @param cls closure for the service
677 * @param client the client we received this message from
678 * @param message the actual message received
681 handle_dht_local_get_result_seen (void *cls, struct GNUNET_SERVER_Client *client,
682 const struct GNUNET_MessageHeader *message)
684 const struct GNUNET_DHT_ClientGetResultSeenMessage *seen;
686 unsigned int hash_count;
687 unsigned int old_count;
688 const struct GNUNET_HashCode *hc;
689 struct FindByUniqueIdContext fui_ctx;
690 struct ClientQueryRecord *cqr;
692 size = ntohs (message->size);
693 if (size < sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage))
696 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
699 seen = (const struct GNUNET_DHT_ClientGetResultSeenMessage *) message;
700 hash_count = (size - sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage)) / sizeof (struct GNUNET_HashCode);
701 if (size != sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage) + hash_count * sizeof (struct GNUNET_HashCode))
704 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
707 hc = (const struct GNUNET_HashCode*) &seen[1];
708 fui_ctx.unique_id = seen->unique_id;
710 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map,
714 if (NULL == (cqr = fui_ctx.cqr))
717 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
720 /* finally, update 'seen' list */
721 old_count = cqr->seen_replies_count;
722 GNUNET_array_grow (cqr->seen_replies,
723 cqr->seen_replies_count,
724 cqr->seen_replies_count + hash_count);
725 memcpy (&cqr->seen_replies[old_count],
727 sizeof (struct GNUNET_HashCode) * hash_count);
732 * Closure for 'remove_by_unique_id'.
734 struct RemoveByUniqueIdContext
737 * Client that issued the removal request.
739 struct ClientList *client;
742 * Unique ID of the request.
749 * Iterator over hash map entries that frees all entries
750 * that match the given client and unique ID.
752 * @param cls unique ID and client to search for in source routes
753 * @param key current key code
754 * @param value value in the hash map, a ClientQueryRecord
755 * @return GNUNET_YES (we should continue to iterate)
758 remove_by_unique_id (void *cls, const struct GNUNET_HashCode * key, void *value)
760 const struct RemoveByUniqueIdContext *ctx = cls;
761 struct ClientQueryRecord *record = value;
763 if (record->unique_id != ctx->unique_id)
765 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
766 "Removing client %p's record for key %s (by unique id)\n",
767 ctx->client->client_handle, GNUNET_h2s (key));
768 return remove_client_records (ctx->client, key, record);
773 * Handler for any generic DHT stop messages, calls the appropriate handler
774 * depending on message type (if processed locally)
776 * @param cls closure for the service
777 * @param client the client we received this message from
778 * @param message the actual message received
782 handle_dht_local_get_stop (void *cls, struct GNUNET_SERVER_Client *client,
783 const struct GNUNET_MessageHeader *message)
785 const struct GNUNET_DHT_ClientGetStopMessage *dht_stop_msg =
786 (const struct GNUNET_DHT_ClientGetStopMessage *) message;
787 struct RemoveByUniqueIdContext ctx;
789 GNUNET_STATISTICS_update (GDS_stats,
791 ("# GET STOP requests received from clients"), 1,
793 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Client %p stopped request for key %s\n",
794 client, GNUNET_h2s (&dht_stop_msg->key));
795 ctx.client = find_active_client (client);
796 ctx.unique_id = dht_stop_msg->unique_id;
797 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, &dht_stop_msg->key,
798 &remove_by_unique_id, &ctx);
799 GNUNET_SERVER_receive_done (client, GNUNET_OK);
804 * Handler for monitor start messages
806 * @param cls closure for the service
807 * @param client the client we received this message from
808 * @param message the actual message received
812 handle_dht_local_monitor (void *cls, struct GNUNET_SERVER_Client *client,
813 const struct GNUNET_MessageHeader *message)
815 struct ClientMonitorRecord *r;
816 const struct GNUNET_DHT_MonitorStartStopMessage *msg;
818 msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
819 r = GNUNET_malloc (sizeof(struct ClientMonitorRecord));
821 r->client = find_active_client(client);
822 r->type = ntohl(msg->type);
823 r->get = ntohs(msg->get);
824 r->get_resp = ntohs(msg->get_resp);
825 r->put = ntohs(msg->put);
826 if (0 == ntohs(msg->filter_key))
830 r->key = GNUNET_malloc (sizeof (struct GNUNET_HashCode));
831 memcpy (r->key, &msg->key, sizeof (struct GNUNET_HashCode));
833 GNUNET_CONTAINER_DLL_insert (monitor_head, monitor_tail, r);
834 GNUNET_SERVER_receive_done (client, GNUNET_OK);
838 * Handler for monitor stop messages
840 * @param cls closure for the service
841 * @param client the client we received this message from
842 * @param message the actual message received
846 handle_dht_local_monitor_stop (void *cls, struct GNUNET_SERVER_Client *client,
847 const struct GNUNET_MessageHeader *message)
849 struct ClientMonitorRecord *r;
850 const struct GNUNET_DHT_MonitorStartStopMessage *msg;
853 msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
859 keys_match = (0 == ntohs(msg->filter_key));
862 keys_match = (0 != ntohs(msg->filter_key)
863 && !memcmp(r->key, &msg->key, sizeof(struct GNUNET_HashCode)));
865 if (find_active_client(client) == r->client
866 && ntohl(msg->type) == r->type
867 && r->get == msg->get
868 && r->get_resp == msg->get_resp
869 && r->put == msg->put
873 GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, r);
874 GNUNET_free_non_null (r->key);
876 GNUNET_SERVER_receive_done (client, GNUNET_OK);
877 return; /* Delete only ONE entry */
882 GNUNET_SERVER_receive_done (client, GNUNET_OK);
887 * Callback called as a result of issuing a GNUNET_SERVER_notify_transmit_ready
888 * request. A ClientList is passed as closure, take the head of the list
889 * and copy it into buf, which has the result of sending the message to the
892 * @param cls closure to this call
893 * @param size maximum number of bytes available to send
894 * @param buf where to copy the actual message to
896 * @return the number of bytes actually copied, 0 indicates failure
899 send_reply_to_client (void *cls, size_t size, void *buf)
901 struct ClientList *client = cls;
903 struct PendingMessage *reply;
907 client->transmit_handle = NULL;
910 /* client disconnected */
911 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
912 "Client %p disconnected, pending messages will be discarded\n",
913 client->client_handle);
917 while ((NULL != (reply = client->pending_head)) &&
918 (size >= off + (msize = ntohs (reply->msg->size))))
920 GNUNET_CONTAINER_DLL_remove (client->pending_head, client->pending_tail,
922 memcpy (&cbuf[off], reply->msg, msize);
924 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u bytes to client %p\n",
925 msize, client->client_handle);
928 process_pending_messages (client);
929 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitted %u/%u bytes to client %p\n",
930 (unsigned int) off, (unsigned int) size, client->client_handle);
936 * Task run to check for messages that need to be sent to a client.
938 * @param client a ClientList, containing the client and any messages to be sent to it
941 process_pending_messages (struct ClientList *client)
943 if ((client->pending_head == NULL) || (client->transmit_handle != NULL))
945 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
946 "Not asking for transmission to %p now: %s\n",
947 client->client_handle,
948 client->pending_head ==
949 NULL ? "no more messages" : "request already pending");
952 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
953 "Asking for transmission of %u bytes to client %p\n",
954 ntohs (client->pending_head->msg->size), client->client_handle);
955 client->transmit_handle =
956 GNUNET_SERVER_notify_transmit_ready (client->client_handle,
957 ntohs (client->pending_head->
959 GNUNET_TIME_UNIT_FOREVER_REL,
960 &send_reply_to_client, client);
965 * Closure for 'forward_reply'
967 struct ForwardReplyContext
971 * Actual message to send to matching clients.
973 struct PendingMessage *pm;
983 enum GNUNET_BLOCK_Type type;
986 * Number of bytes in data.
991 * Do we need to copy 'pm' because it was already used?
999 * Iterator over hash map entries that send a given reply to
1000 * each of the matching clients. With some tricky recycling
1003 * @param cls the 'struct ForwardReplyContext'
1004 * @param key current key
1005 * @param value value in the hash map, a ClientQueryRecord
1006 * @return GNUNET_YES (we should continue to iterate),
1007 * if the result is mal-formed, GNUNET_NO
1010 forward_reply (void *cls, const struct GNUNET_HashCode * key, void *value)
1012 struct ForwardReplyContext *frc = cls;
1013 struct ClientQueryRecord *record = value;
1014 struct PendingMessage *pm;
1015 struct GNUNET_DHT_ClientResultMessage *reply;
1016 enum GNUNET_BLOCK_EvaluationResult eval;
1018 struct GNUNET_HashCode ch;
1021 if (LOG_ROUTE_DETAILS_STDERR)
1024 "XDHT CLIENT-RESULT %s @ %u\n",
1028 if ((record->type != GNUNET_BLOCK_TYPE_ANY) && (record->type != frc->type))
1030 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1031 "Record type missmatch, not passing request for key %s to local client\n",
1033 GNUNET_STATISTICS_update (GDS_stats,
1035 ("# Key match, type mismatches in REPLY to CLIENT"),
1037 return GNUNET_YES; /* type mismatch */
1039 GNUNET_CRYPTO_hash (frc->data, frc->data_size, &ch);
1040 for (i = 0; i < record->seen_replies_count; i++)
1041 if (0 == memcmp (&record->seen_replies[i], &ch, sizeof (struct GNUNET_HashCode)))
1043 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1044 "Duplicate reply, not passing request for key %s to local client\n",
1046 GNUNET_STATISTICS_update (GDS_stats,
1048 ("# Duplicate REPLIES to CLIENT request dropped"),
1050 return GNUNET_YES; /* duplicate */
1053 GNUNET_BLOCK_evaluate (GDS_block_context, record->type, key, NULL, 0,
1054 record->xquery, record->xquery_size, frc->data,
1056 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1057 "Evaluation result is %d for key %s for local client's query\n",
1058 (int) eval, GNUNET_h2s (key));
1061 case GNUNET_BLOCK_EVALUATION_OK_LAST:
1062 do_free = GNUNET_YES;
1064 case GNUNET_BLOCK_EVALUATION_OK_MORE:
1065 GNUNET_array_append (record->seen_replies, record->seen_replies_count, ch);
1066 do_free = GNUNET_NO;
1068 case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
1069 /* should be impossible to encounter here */
1072 case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
1073 GNUNET_break_op (0);
1075 case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
1078 case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
1081 case GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT:
1083 case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
1084 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1085 _("Unsupported block type (%u) in request!\n"), record->type);
1091 if (GNUNET_NO == frc->do_copy)
1093 /* first time, we can use the original data */
1095 frc->do_copy = GNUNET_YES;
1099 /* two clients waiting for same reply, must copy for queueing */
1100 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
1101 ntohs (frc->pm->msg->size));
1102 memcpy (pm, frc->pm,
1103 sizeof (struct PendingMessage) + ntohs (frc->pm->msg->size));
1104 pm->next = pm->prev = NULL;
1105 pm->msg = (struct GNUNET_MessageHeader *) &pm[1];
1107 GNUNET_STATISTICS_update (GDS_stats,
1108 gettext_noop ("# RESULTS queued for clients"), 1,
1110 reply = (struct GNUNET_DHT_ClientResultMessage *) &pm[1];
1111 reply->unique_id = record->unique_id;
1112 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1113 "Queueing reply to query %s for client %p\n", GNUNET_h2s (key),
1114 record->client->client_handle);
1115 add_pending_message (record->client, pm);
1116 if (GNUNET_YES == do_free)
1117 remove_client_records (record->client, key, record);
1123 * Handle a reply we've received from another peer. If the reply
1124 * matches any of our pending queries, forward it to the respective
1127 * @param expiration when will the reply expire
1128 * @param key the query this reply is for
1129 * @param get_path_length number of peers in 'get_path'
1130 * @param get_path path the reply took on get
1131 * @param put_path_length number of peers in 'put_path'
1132 * @param put_path path the reply took on put
1133 * @param type type of the reply
1134 * @param data_size number of bytes in 'data'
1135 * @param data application payload data
1138 GDS_CLIENTS_handle_reply (struct GNUNET_TIME_Absolute expiration,
1139 const struct GNUNET_HashCode *key,
1140 unsigned int get_path_length,
1141 const struct GNUNET_PeerIdentity *get_path,
1142 unsigned int put_path_length,
1143 const struct GNUNET_PeerIdentity *put_path,
1144 enum GNUNET_BLOCK_Type type, size_t data_size,
1147 struct ForwardReplyContext frc;
1148 struct PendingMessage *pm;
1149 struct GNUNET_DHT_ClientResultMessage *reply;
1150 struct GNUNET_PeerIdentity *paths;
1153 if (NULL == GNUNET_CONTAINER_multihashmap_get (forward_map, key))
1155 GNUNET_STATISTICS_update (GDS_stats,
1157 ("# REPLIES ignored for CLIENTS (no match)"), 1,
1159 return; /* no matching request, fast exit! */
1162 sizeof (struct GNUNET_DHT_ClientResultMessage) + data_size +
1163 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity);
1164 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1166 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1167 _("Could not pass reply to client, message too big!\n"));
1170 pm = GNUNET_malloc (msize + sizeof (struct PendingMessage));
1171 reply = (struct GNUNET_DHT_ClientResultMessage *) &pm[1];
1172 pm->msg = &reply->header;
1173 reply->header.size = htons ((uint16_t) msize);
1174 reply->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_CLIENT_RESULT);
1175 reply->type = htonl (type);
1176 reply->get_path_length = htonl (get_path_length);
1177 reply->put_path_length = htonl (put_path_length);
1178 reply->unique_id = 0; /* filled in later */
1179 reply->expiration = GNUNET_TIME_absolute_hton (expiration);
1181 paths = (struct GNUNET_PeerIdentity *) &reply[1];
1182 memcpy (paths, put_path,
1183 sizeof (struct GNUNET_PeerIdentity) * put_path_length);
1184 memcpy (&paths[put_path_length], get_path,
1185 sizeof (struct GNUNET_PeerIdentity) * get_path_length);
1186 memcpy (&paths[get_path_length + put_path_length], data, data_size);
1187 frc.do_copy = GNUNET_NO;
1190 frc.data_size = data_size;
1192 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, key, &forward_reply,
1194 if (GNUNET_NO == frc.do_copy)
1196 /* did not match any of the requests, free! */
1197 GNUNET_STATISTICS_update (GDS_stats,
1199 ("# REPLIES ignored for CLIENTS (no match)"), 1,
1207 * Check if some client is monitoring GET messages and notify
1208 * them in that case.
1210 * @param options Options, for instance RecordRoute, DemultiplexEverywhere.
1211 * @param type The type of data in the request.
1212 * @param hop_count Hop count so far.
1213 * @param path_length number of entries in path (or 0 if not recorded).
1214 * @param path peers on the GET path (or NULL if not recorded).
1215 * @param desired_replication_level Desired replication level.
1216 * @param key Key of the requested data.
1219 GDS_CLIENTS_process_get (uint32_t options,
1220 enum GNUNET_BLOCK_Type type,
1222 uint32_t desired_replication_level,
1223 unsigned int path_length,
1224 const struct GNUNET_PeerIdentity *path,
1225 const struct GNUNET_HashCode * key)
1227 struct ClientMonitorRecord *m;
1228 struct ClientList **cl;
1229 unsigned int cl_size;
1233 for (m = monitor_head; NULL != m; m = m->next)
1235 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1237 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1239 struct PendingMessage *pm;
1240 struct GNUNET_DHT_MonitorGetMessage *mmsg;
1241 struct GNUNET_PeerIdentity *msg_path;
1245 /* Don't send duplicates */
1246 for (i = 0; i < cl_size; i++)
1247 if (cl[i] == m->client)
1251 GNUNET_array_append (cl, cl_size, m->client);
1253 msize = path_length * sizeof (struct GNUNET_PeerIdentity);
1254 msize += sizeof (struct GNUNET_DHT_MonitorGetMessage);
1255 msize += sizeof (struct PendingMessage);
1256 pm = GNUNET_malloc (msize);
1257 mmsg = (struct GNUNET_DHT_MonitorGetMessage *) &pm[1];
1258 pm->msg = &mmsg->header;
1259 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1260 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_GET);
1261 mmsg->options = htonl(options);
1262 mmsg->type = htonl(type);
1263 mmsg->hop_count = htonl(hop_count);
1264 mmsg->desired_replication_level = htonl(desired_replication_level);
1265 mmsg->get_path_length = htonl(path_length);
1266 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1267 msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1268 if (path_length > 0)
1269 memcpy (msg_path, path,
1270 path_length * sizeof (struct GNUNET_PeerIdentity));
1271 add_pending_message (m->client, pm);
1274 GNUNET_free_non_null (cl);
1279 * Check if some client is monitoring GET RESP messages and notify
1280 * them in that case.
1282 * @param type The type of data in the result.
1283 * @param get_path Peers on GET path (or NULL if not recorded).
1284 * @param get_path_length number of entries in get_path.
1285 * @param put_path peers on the PUT path (or NULL if not recorded).
1286 * @param put_path_length number of entries in get_path.
1287 * @param exp Expiration time of the data.
1288 * @param key Key of the data.
1289 * @param data Pointer to the result data.
1290 * @param size Number of bytes in data.
1293 GDS_CLIENTS_process_get_resp (enum GNUNET_BLOCK_Type type,
1294 const struct GNUNET_PeerIdentity *get_path,
1295 unsigned int get_path_length,
1296 const struct GNUNET_PeerIdentity *put_path,
1297 unsigned int put_path_length,
1298 struct GNUNET_TIME_Absolute exp,
1299 const struct GNUNET_HashCode * key,
1303 struct ClientMonitorRecord *m;
1304 struct ClientList **cl;
1305 unsigned int cl_size;
1309 for (m = monitor_head; NULL != m; m = m->next)
1311 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1313 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1315 struct PendingMessage *pm;
1316 struct GNUNET_DHT_MonitorGetRespMessage *mmsg;
1317 struct GNUNET_PeerIdentity *path;
1321 /* Don't send duplicates */
1322 for (i = 0; i < cl_size; i++)
1323 if (cl[i] == m->client)
1327 GNUNET_array_append (cl, cl_size, m->client);
1330 msize += (get_path_length + put_path_length)
1331 * sizeof (struct GNUNET_PeerIdentity);
1332 msize += sizeof (struct GNUNET_DHT_MonitorGetRespMessage);
1333 msize += sizeof (struct PendingMessage);
1334 pm = GNUNET_malloc (msize);
1335 mmsg = (struct GNUNET_DHT_MonitorGetRespMessage *) &pm[1];
1336 pm->msg = (struct GNUNET_MessageHeader *) mmsg;
1337 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1338 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_GET_RESP);
1339 mmsg->type = htonl(type);
1340 mmsg->put_path_length = htonl(put_path_length);
1341 mmsg->get_path_length = htonl(get_path_length);
1342 path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1343 if (put_path_length > 0)
1345 memcpy (path, put_path,
1346 put_path_length * sizeof (struct GNUNET_PeerIdentity));
1347 path = &path[put_path_length];
1349 if (get_path_length > 0)
1350 memcpy (path, get_path,
1351 get_path_length * sizeof (struct GNUNET_PeerIdentity));
1352 mmsg->expiration_time = GNUNET_TIME_absolute_hton(exp);
1353 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1355 memcpy (&path[get_path_length], data, size);
1356 add_pending_message (m->client, pm);
1359 GNUNET_free_non_null (cl);
1364 * Check if some client is monitoring PUT messages and notify
1365 * them in that case.
1367 * @param options Options, for instance RecordRoute, DemultiplexEverywhere.
1368 * @param type The type of data in the request.
1369 * @param hop_count Hop count so far.
1370 * @param path_length number of entries in path (or 0 if not recorded).
1371 * @param path peers on the PUT path (or NULL if not recorded).
1372 * @param desired_replication_level Desired replication level.
1373 * @param exp Expiration time of the data.
1374 * @param key Key under which data is to be stored.
1375 * @param data Pointer to the data carried.
1376 * @param size Number of bytes in data.
1379 GDS_CLIENTS_process_put (uint32_t options,
1380 enum GNUNET_BLOCK_Type type,
1382 uint32_t desired_replication_level,
1383 unsigned int path_length,
1384 const struct GNUNET_PeerIdentity *path,
1385 struct GNUNET_TIME_Absolute exp,
1386 const struct GNUNET_HashCode * key,
1390 struct ClientMonitorRecord *m;
1391 struct ClientList **cl;
1392 unsigned int cl_size;
1396 for (m = monitor_head; NULL != m; m = m->next)
1398 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1400 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1402 struct PendingMessage *pm;
1403 struct GNUNET_DHT_MonitorPutMessage *mmsg;
1404 struct GNUNET_PeerIdentity *msg_path;
1408 /* Don't send duplicates */
1409 for (i = 0; i < cl_size; i++)
1410 if (cl[i] == m->client)
1414 GNUNET_array_append (cl, cl_size, m->client);
1417 msize += path_length * sizeof (struct GNUNET_PeerIdentity);
1418 msize += sizeof (struct GNUNET_DHT_MonitorPutMessage);
1419 msize += sizeof (struct PendingMessage);
1420 pm = GNUNET_malloc (msize);
1421 mmsg = (struct GNUNET_DHT_MonitorPutMessage *) &pm[1];
1422 pm->msg = (struct GNUNET_MessageHeader *) mmsg;
1423 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1424 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_PUT);
1425 mmsg->options = htonl(options);
1426 mmsg->type = htonl(type);
1427 mmsg->hop_count = htonl(hop_count);
1428 mmsg->desired_replication_level = htonl(desired_replication_level);
1429 mmsg->put_path_length = htonl(path_length);
1430 msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1431 if (path_length > 0)
1433 memcpy (msg_path, path,
1434 path_length * sizeof (struct GNUNET_PeerIdentity));
1436 mmsg->expiration_time = GNUNET_TIME_absolute_hton(exp);
1437 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1439 memcpy (&msg_path[path_length], data, size);
1440 add_pending_message (m->client, pm);
1443 GNUNET_free_non_null (cl);
1448 * Initialize client subsystem.
1450 * @param server the initialized server
1453 GDS_CLIENTS_init (struct GNUNET_SERVER_Handle *server)
1455 static struct GNUNET_SERVER_MessageHandler plugin_handlers[] = {
1456 {&handle_dht_local_put, NULL,
1457 GNUNET_MESSAGE_TYPE_DHT_CLIENT_PUT, 0},
1458 {&handle_dht_local_get, NULL,
1459 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET, 0},
1460 {&handle_dht_local_get_stop, NULL,
1461 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET_STOP,
1462 sizeof (struct GNUNET_DHT_ClientGetStopMessage)},
1463 {&handle_dht_local_monitor, NULL,
1464 GNUNET_MESSAGE_TYPE_DHT_MONITOR_START,
1465 sizeof (struct GNUNET_DHT_MonitorStartStopMessage)},
1466 {&handle_dht_local_monitor_stop, NULL,
1467 GNUNET_MESSAGE_TYPE_DHT_MONITOR_STOP,
1468 sizeof (struct GNUNET_DHT_MonitorStartStopMessage)},
1469 {&handle_dht_local_get_result_seen, NULL,
1470 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET_RESULTS_KNOWN, 0},
1473 forward_map = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
1474 retry_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1475 GNUNET_SERVER_add_handlers (server, plugin_handlers);
1476 GNUNET_SERVER_disconnect_notify (server, &handle_client_disconnect, NULL);
1481 * Shutdown client subsystem.
1486 GNUNET_assert (client_head == NULL);
1487 GNUNET_assert (client_tail == NULL);
1488 if (GNUNET_SCHEDULER_NO_TASK != retry_task)
1490 GNUNET_SCHEDULER_cancel (retry_task);
1491 retry_task = GNUNET_SCHEDULER_NO_TASK;
1493 if (NULL != retry_heap)
1495 GNUNET_assert (0 == GNUNET_CONTAINER_heap_get_size (retry_heap));
1496 GNUNET_CONTAINER_heap_destroy (retry_heap);
1499 if (NULL != forward_map)
1501 GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (forward_map));
1502 GNUNET_CONTAINER_multihashmap_destroy (forward_map);
1507 /* end of gnunet-service-dht_clients.c */