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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_TRAFFIC(kind,...) GNUNET_log_from (kind, "dht-traffic",__VA_ARGS__)
44 #define LOG(kind,...) GNUNET_log_from (kind, "dht-clients",__VA_ARGS__)
47 * Linked list of messages to send to clients.
52 * Pointer to next item in the list
54 struct PendingMessage *next;
57 * Pointer to previous item in the list
59 struct PendingMessage *prev;
62 * Actual message to be sent, allocated at the end of the struct:
63 * // msg = (cast) &pm[1];
64 * // memcpy (&pm[1], data, len);
66 const struct GNUNET_MessageHeader *msg;
72 * Struct containing information about a client,
73 * handle to connect to it, and any pending messages
74 * that need to be sent to it.
79 * Linked list of active clients
81 struct ClientList *next;
84 * Linked list of active clients
86 struct ClientList *prev;
89 * The handle to this client
91 struct GNUNET_SERVER_Client *client_handle;
94 * Handle to the current transmission request, NULL
97 struct GNUNET_SERVER_TransmitHandle *transmit_handle;
100 * Linked list of pending messages for this client
102 struct PendingMessage *pending_head;
105 * Tail of linked list of pending messages for this client
107 struct PendingMessage *pending_tail;
113 * Entry in the local forwarding map for a client's GET request.
115 struct ClientQueryRecord
119 * The key this request was about
121 struct GNUNET_HashCode key;
124 * Client responsible for the request.
126 struct ClientList *client;
129 * Extended query (see gnunet_block_lib.h), allocated at the end of this struct.
134 * Replies we have already seen for this request.
136 struct GNUNET_HashCode *seen_replies;
139 * Pointer to this nodes heap location in the retry-heap (for fast removal)
141 struct GNUNET_CONTAINER_HeapNode *hnode;
144 * What's the delay between re-try operations that we currently use for this
147 struct GNUNET_TIME_Relative retry_frequency;
150 * What's the next time we should re-try this request?
152 struct GNUNET_TIME_Absolute retry_time;
155 * The unique identifier of this request
160 * Number of bytes in xquery.
165 * Number of entries in 'seen_replies'.
167 unsigned int seen_replies_count;
170 * Desired replication level
172 uint32_t replication;
175 * Any message options for this request
177 uint32_t msg_options;
180 * The type for the data for the GET request.
182 enum GNUNET_BLOCK_Type type;
188 * Struct containing paremeters of monitoring requests.
190 struct ClientMonitorRecord
194 * Next element in DLL.
196 struct ClientMonitorRecord *next;
199 * Previous element in DLL.
201 struct ClientMonitorRecord *prev;
204 * Type of blocks that are of interest
206 enum GNUNET_BLOCK_Type type;
209 * Key of data of interest, NULL for all.
211 struct GNUNET_HashCode *key;
214 * Flag whether to notify about GET messages.
219 * Flag whether to notify about GET_REPONSE messages.
224 * Flag whether to notify about PUT messages.
229 * Client to notify of these requests.
231 struct ClientList *client;
236 * List of active clients.
238 static struct ClientList *client_head;
241 * List of active clients.
243 static struct ClientList *client_tail;
246 * List of active monitoring requests.
248 static struct ClientMonitorRecord *monitor_head;
251 * List of active monitoring requests.
253 static struct ClientMonitorRecord *monitor_tail;
256 * Hashmap for fast key based lookup, maps keys to `struct ClientQueryRecord` entries.
258 static struct GNUNET_CONTAINER_MultiHashMap *forward_map;
261 * Heap with all of our client's request, sorted by retry time (earliest on top).
263 static struct GNUNET_CONTAINER_Heap *retry_heap;
266 * Task that re-transmits requests (using retry_heap).
268 static struct GNUNET_SCHEDULER_Task * retry_task;
272 * Task run to check for messages that need to be sent to a client.
274 * @param client a ClientList, containing the client and any messages to be sent to it
277 process_pending_messages (struct ClientList *client);
281 * Add a PendingMessage to the clients list of messages to be sent
283 * @param client the active client to send the message to
284 * @param pending_message the actual message to send
287 add_pending_message (struct ClientList *client,
288 struct PendingMessage *pending_message)
290 GNUNET_CONTAINER_DLL_insert_tail (client->pending_head, client->pending_tail,
292 process_pending_messages (client);
297 * Find a client if it exists, add it otherwise.
299 * @param client the server handle to the client
301 * @return the client if found, a new client otherwise
303 static struct ClientList *
304 find_active_client (struct GNUNET_SERVER_Client *client)
306 struct ClientList *pos = client_head;
307 struct ClientList *ret;
311 if (pos->client_handle == client)
315 ret = GNUNET_new (struct ClientList);
316 ret->client_handle = client;
317 GNUNET_CONTAINER_DLL_insert (client_head, client_tail, ret);
323 * Iterator over hash map entries that frees all entries
324 * associated with the given client.
326 * @param cls client to search for in source routes
327 * @param key current key code (ignored)
328 * @param value value in the hash map, a ClientQueryRecord
329 * @return #GNUNET_YES (we should continue to iterate)
332 remove_client_records (void *cls, const struct GNUNET_HashCode * key, void *value)
334 struct ClientList *client = cls;
335 struct ClientQueryRecord *record = value;
337 if (record->client != client)
339 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
340 "Removing client %p's record for key %s\n", client,
342 GNUNET_assert (GNUNET_YES ==
343 GNUNET_CONTAINER_multihashmap_remove (forward_map, key,
345 if (NULL != record->hnode)
346 GNUNET_CONTAINER_heap_remove_node (record->hnode);
347 GNUNET_array_grow (record->seen_replies, record->seen_replies_count, 0);
348 GNUNET_free (record);
354 * Functions with this signature are called whenever a client
355 * is disconnected on the network level.
357 * @param cls closure (NULL for dht)
358 * @param client identification of the client; NULL
359 * for the last call when the server is destroyed
362 handle_client_disconnect (void *cls,
363 struct GNUNET_SERVER_Client *client)
365 struct ClientList *pos;
366 struct PendingMessage *reply;
367 struct ClientMonitorRecord *monitor;
369 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
370 "Local client %p disconnects\n",
372 pos = find_active_client (client);
373 GNUNET_CONTAINER_DLL_remove (client_head, client_tail, pos);
374 if (pos->transmit_handle != NULL)
375 GNUNET_SERVER_notify_transmit_ready_cancel (pos->transmit_handle);
376 while (NULL != (reply = pos->pending_head))
378 GNUNET_CONTAINER_DLL_remove (pos->pending_head, pos->pending_tail, reply);
381 monitor = monitor_head;
382 while (NULL != monitor)
384 if (monitor->client == pos)
386 struct ClientMonitorRecord *next;
388 GNUNET_free_non_null (monitor->key);
389 next = monitor->next;
390 GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, monitor);
391 GNUNET_free (monitor);
395 monitor = monitor->next;
397 GNUNET_CONTAINER_multihashmap_iterate (forward_map, &remove_client_records,
404 * Route the given request via the DHT. This includes updating
405 * the bloom filter and retransmission times, building the P2P
406 * message and initiating the routing operation.
409 transmit_request (struct ClientQueryRecord *cqr)
411 int32_t reply_bf_mutator;
412 struct GNUNET_CONTAINER_BloomFilter *reply_bf;
413 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
415 GNUNET_STATISTICS_update (GDS_stats,
417 ("# GET requests from clients injected"), 1,
420 (int32_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
423 GNUNET_BLOCK_construct_bloomfilter (reply_bf_mutator, cqr->seen_replies,
424 cqr->seen_replies_count);
426 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
427 GNUNET_CONSTANTS_BLOOMFILTER_K);
428 LOG (GNUNET_ERROR_TYPE_DEBUG,
429 "Initiating GET for %s, replication %u, already have %u replies\n",
430 GNUNET_h2s (&cqr->key),
432 cqr->seen_replies_count);
433 GDS_NEIGHBOURS_handle_get (cqr->type, cqr->msg_options, cqr->replication,
435 &cqr->key, cqr->xquery, cqr->xquery_size, reply_bf,
436 reply_bf_mutator, peer_bf);
437 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
438 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
440 /* exponential back-off for retries.
441 * max GNUNET_TIME_STD_EXPONENTIAL_BACKOFF_THRESHOLD (15 min) */
442 cqr->retry_frequency = GNUNET_TIME_STD_BACKOFF (cqr->retry_frequency);
443 cqr->retry_time = GNUNET_TIME_relative_to_absolute (cqr->retry_frequency);
448 * Task that looks at the 'retry_heap' and transmits all of the requests
449 * on the heap that are ready for transmission. Then re-schedules
450 * itself (unless the heap is empty).
455 transmit_next_request_task (void *cls)
457 struct ClientQueryRecord *cqr;
458 struct GNUNET_TIME_Relative delay;
461 while (NULL != (cqr = GNUNET_CONTAINER_heap_remove_root (retry_heap)))
464 delay = GNUNET_TIME_absolute_get_remaining (cqr->retry_time);
465 if (delay.rel_value_us > 0)
468 GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
469 cqr->retry_time.abs_value_us);
471 GNUNET_SCHEDULER_add_delayed (delay, &transmit_next_request_task,
475 transmit_request (cqr);
477 GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
478 cqr->retry_time.abs_value_us);
484 * Handler for PUT messages.
486 * @param cls closure for the service
487 * @param client the client we received this message from
488 * @param message the actual message received
491 handle_dht_local_put (void *cls, struct GNUNET_SERVER_Client *client,
492 const struct GNUNET_MessageHeader *message)
494 const struct GNUNET_DHT_ClientPutMessage *dht_msg;
495 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
497 struct PendingMessage *pm;
498 struct GNUNET_DHT_ClientPutConfirmationMessage *conf;
500 size = ntohs (message->size);
501 if (size < sizeof (struct GNUNET_DHT_ClientPutMessage))
504 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
507 GNUNET_STATISTICS_update (GDS_stats,
509 ("# PUT requests received from clients"), 1,
511 dht_msg = (const struct GNUNET_DHT_ClientPutMessage *) message;
512 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "R5N CLIENT-PUT %s\n",
513 GNUNET_h2s_full (&dht_msg->key));
514 /* give to local clients */
515 LOG (GNUNET_ERROR_TYPE_DEBUG,
516 "Handling local PUT of %u-bytes for query %s\n",
517 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
518 GNUNET_h2s (&dht_msg->key));
519 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
520 &dht_msg->key, 0, NULL, 0, NULL,
521 ntohl (dht_msg->type),
522 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
525 GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
526 &dht_msg->key, 0, NULL, ntohl (dht_msg->type),
527 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
529 /* route to other peers */
531 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
532 GNUNET_CONSTANTS_BLOOMFILTER_K);
533 GDS_NEIGHBOURS_handle_put (ntohl (dht_msg->type), ntohl (dht_msg->options),
534 ntohl (dht_msg->desired_replication_level),
535 GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
537 peer_bf, &dht_msg->key, 0, NULL, &dht_msg[1],
539 sizeof (struct GNUNET_DHT_ClientPutMessage));
540 GDS_CLIENTS_process_put (ntohl (dht_msg->options),
541 ntohl (dht_msg->type),
543 ntohl (dht_msg->desired_replication_level),
545 GDS_NEIGHBOURS_get_id(),
546 GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
549 size - sizeof (struct GNUNET_DHT_ClientPutMessage));
550 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
551 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
552 sizeof (struct GNUNET_DHT_ClientPutConfirmationMessage));
553 conf = (struct GNUNET_DHT_ClientPutConfirmationMessage *) &pm[1];
554 conf->header.size = htons (sizeof (struct GNUNET_DHT_ClientPutConfirmationMessage));
555 conf->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_CLIENT_PUT_OK);
556 conf->reserved = htonl (0);
557 conf->unique_id = dht_msg->unique_id;
558 pm->msg = &conf->header;
559 add_pending_message (find_active_client (client), pm);
560 GNUNET_SERVER_receive_done (client, GNUNET_OK);
565 * Handler for DHT GET messages from the client.
567 * @param cls closure for the service
568 * @param client the client we received this message from
569 * @param message the actual message received
572 handle_dht_local_get (void *cls, struct GNUNET_SERVER_Client *client,
573 const struct GNUNET_MessageHeader *message)
575 const struct GNUNET_DHT_ClientGetMessage *get;
576 struct ClientQueryRecord *cqr;
581 size = ntohs (message->size);
582 if (size < sizeof (struct GNUNET_DHT_ClientGetMessage))
585 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
588 xquery_size = size - sizeof (struct GNUNET_DHT_ClientGetMessage);
589 get = (const struct GNUNET_DHT_ClientGetMessage *) message;
590 xquery = (const char *) &get[1];
591 GNUNET_STATISTICS_update (GDS_stats,
593 ("# GET requests received from clients"), 1,
595 LOG (GNUNET_ERROR_TYPE_DEBUG,
596 "Received GET request for %s from local client %p, xq: %.*s\n",
597 GNUNET_h2s (&get->key), client, xquery_size, xquery);
599 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "R5N CLIENT-GET %s\n",
600 GNUNET_h2s_full (&get->key));
603 cqr = GNUNET_malloc (sizeof (struct ClientQueryRecord) + xquery_size);
605 cqr->client = find_active_client (client);
606 cqr->xquery = (void *) &cqr[1];
607 memcpy (&cqr[1], xquery, xquery_size);
608 cqr->hnode = GNUNET_CONTAINER_heap_insert (retry_heap, cqr, 0);
609 cqr->retry_frequency = GNUNET_TIME_UNIT_SECONDS;
610 cqr->retry_time = GNUNET_TIME_absolute_get ();
611 cqr->unique_id = get->unique_id;
612 cqr->xquery_size = xquery_size;
613 cqr->replication = ntohl (get->desired_replication_level);
614 cqr->msg_options = ntohl (get->options);
615 cqr->type = ntohl (get->type);
616 // FIXME use cqr->key, set multihashmap create to GNUNET_YES
617 GNUNET_CONTAINER_multihashmap_put (forward_map, &get->key, cqr,
618 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
619 GDS_CLIENTS_process_get (ntohl (get->options),
622 ntohl (get->desired_replication_level),
624 GDS_NEIGHBOURS_get_id(),
626 /* start remote requests */
627 if (NULL != retry_task)
628 GNUNET_SCHEDULER_cancel (retry_task);
629 retry_task = GNUNET_SCHEDULER_add_now (&transmit_next_request_task, NULL);
630 /* perform local lookup */
631 GDS_DATACACHE_handle_get (&get->key, cqr->type, cqr->xquery, xquery_size,
633 GNUNET_SERVER_receive_done (client, GNUNET_OK);
638 * Closure for 'find_by_unique_id'.
640 struct FindByUniqueIdContext
643 * Where to store the result, if found.
645 struct ClientQueryRecord *cqr;
652 * Function called for each existing DHT record for the given
653 * query. Checks if it matches the UID given in the closure
654 * and if so returns the entry as a result.
656 * @param cls the search context
657 * @param key query for the lookup (not used)
658 * @param value the 'struct ClientQueryRecord'
659 * @return GNUNET_YES to continue iteration (result not yet found)
662 find_by_unique_id (void *cls,
663 const struct GNUNET_HashCode *key,
666 struct FindByUniqueIdContext *fui_ctx = cls;
667 struct ClientQueryRecord *cqr = value;
669 if (cqr->unique_id != fui_ctx->unique_id)
677 * Handler for "GET result seen" messages from the client.
679 * @param cls closure for the service
680 * @param client the client we received this message from
681 * @param message the actual message received
684 handle_dht_local_get_result_seen (void *cls, struct GNUNET_SERVER_Client *client,
685 const struct GNUNET_MessageHeader *message)
687 const struct GNUNET_DHT_ClientGetResultSeenMessage *seen;
689 unsigned int hash_count;
690 unsigned int old_count;
691 const struct GNUNET_HashCode *hc;
692 struct FindByUniqueIdContext fui_ctx;
693 struct ClientQueryRecord *cqr;
695 size = ntohs (message->size);
696 if (size < sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage))
699 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
702 seen = (const struct GNUNET_DHT_ClientGetResultSeenMessage *) message;
703 hash_count = (size - sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage)) / sizeof (struct GNUNET_HashCode);
704 if (size != sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage) + hash_count * sizeof (struct GNUNET_HashCode))
707 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
710 hc = (const struct GNUNET_HashCode*) &seen[1];
711 fui_ctx.unique_id = seen->unique_id;
713 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map,
717 if (NULL == (cqr = fui_ctx.cqr))
720 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
723 /* finally, update 'seen' list */
724 old_count = cqr->seen_replies_count;
725 GNUNET_array_grow (cqr->seen_replies,
726 cqr->seen_replies_count,
727 cqr->seen_replies_count + hash_count);
728 memcpy (&cqr->seen_replies[old_count],
730 sizeof (struct GNUNET_HashCode) * hash_count);
735 * Closure for 'remove_by_unique_id'.
737 struct RemoveByUniqueIdContext
740 * Client that issued the removal request.
742 struct ClientList *client;
745 * Unique ID of the request.
752 * Iterator over hash map entries that frees all entries
753 * that match the given client and unique ID.
755 * @param cls unique ID and client to search for in source routes
756 * @param key current key code
757 * @param value value in the hash map, a ClientQueryRecord
758 * @return GNUNET_YES (we should continue to iterate)
761 remove_by_unique_id (void *cls, const struct GNUNET_HashCode * key, void *value)
763 const struct RemoveByUniqueIdContext *ctx = cls;
764 struct ClientQueryRecord *record = value;
766 if (record->unique_id != ctx->unique_id)
768 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
769 "Removing client %p's record for key %s (by unique id)\n",
770 ctx->client->client_handle, GNUNET_h2s (key));
771 return remove_client_records (ctx->client, key, record);
776 * Handler for any generic DHT stop messages, calls the appropriate handler
777 * depending on message type (if processed locally)
779 * @param cls closure for the service
780 * @param client the client we received this message from
781 * @param message the actual message received
785 handle_dht_local_get_stop (void *cls,
786 struct GNUNET_SERVER_Client *client,
787 const struct GNUNET_MessageHeader *message)
789 const struct GNUNET_DHT_ClientGetStopMessage *dht_stop_msg =
790 (const struct GNUNET_DHT_ClientGetStopMessage *) message;
791 struct RemoveByUniqueIdContext ctx;
793 GNUNET_STATISTICS_update (GDS_stats,
795 ("# GET STOP requests received from clients"), 1,
797 LOG (GNUNET_ERROR_TYPE_DEBUG,
798 "Received GET STOP request for %s from local client %p\n",
799 GNUNET_h2s (&dht_stop_msg->key),
801 ctx.client = find_active_client (client);
802 ctx.unique_id = dht_stop_msg->unique_id;
803 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, &dht_stop_msg->key,
804 &remove_by_unique_id, &ctx);
805 GNUNET_SERVER_receive_done (client, GNUNET_OK);
810 * Handler for monitor start messages
812 * @param cls closure for the service
813 * @param client the client we received this message from
814 * @param message the actual message received
818 handle_dht_local_monitor (void *cls, struct GNUNET_SERVER_Client *client,
819 const struct GNUNET_MessageHeader *message)
821 struct ClientMonitorRecord *r;
822 const struct GNUNET_DHT_MonitorStartStopMessage *msg;
824 msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
825 r = GNUNET_new (struct ClientMonitorRecord);
827 r->client = find_active_client(client);
828 r->type = ntohl(msg->type);
829 r->get = ntohs(msg->get);
830 r->get_resp = ntohs(msg->get_resp);
831 r->put = ntohs(msg->put);
832 if (0 == ntohs(msg->filter_key))
836 r->key = GNUNET_new (struct GNUNET_HashCode);
837 memcpy (r->key, &msg->key, sizeof (struct GNUNET_HashCode));
839 GNUNET_CONTAINER_DLL_insert (monitor_head, monitor_tail, r);
840 GNUNET_SERVER_receive_done (client, GNUNET_OK);
845 * Handler for monitor stop messages
847 * @param cls closure for the service
848 * @param client the client we received this message from
849 * @param message the actual message received
853 handle_dht_local_monitor_stop (void *cls, struct GNUNET_SERVER_Client *client,
854 const struct GNUNET_MessageHeader *message)
856 struct ClientMonitorRecord *r;
857 const struct GNUNET_DHT_MonitorStartStopMessage *msg;
860 msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
866 keys_match = (0 == ntohs(msg->filter_key));
869 keys_match = (0 != ntohs(msg->filter_key)
870 && !memcmp(r->key, &msg->key, sizeof(struct GNUNET_HashCode)));
872 if (find_active_client(client) == r->client
873 && ntohl(msg->type) == r->type
874 && r->get == msg->get
875 && r->get_resp == msg->get_resp
876 && r->put == msg->put
880 GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, r);
881 GNUNET_free_non_null (r->key);
883 GNUNET_SERVER_receive_done (client, GNUNET_OK);
884 return; /* Delete only ONE entry */
889 GNUNET_SERVER_receive_done (client, GNUNET_OK);
894 * Callback called as a result of issuing a GNUNET_SERVER_notify_transmit_ready
895 * request. A ClientList is passed as closure, take the head of the list
896 * and copy it into buf, which has the result of sending the message to the
899 * @param cls closure to this call
900 * @param size maximum number of bytes available to send
901 * @param buf where to copy the actual message to
903 * @return the number of bytes actually copied, 0 indicates failure
906 send_reply_to_client (void *cls, size_t size, void *buf)
908 struct ClientList *client = cls;
910 struct PendingMessage *reply;
914 client->transmit_handle = NULL;
917 /* client disconnected */
918 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
919 "Client %p disconnected, pending messages will be discarded\n",
920 client->client_handle);
924 while ((NULL != (reply = client->pending_head)) &&
925 (size >= off + (msize = ntohs (reply->msg->size))))
927 GNUNET_CONTAINER_DLL_remove (client->pending_head, client->pending_tail,
929 memcpy (&cbuf[off], reply->msg, msize);
931 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
932 "Transmitting %u bytes to client %p\n",
933 (unsigned int) msize,
934 client->client_handle);
937 process_pending_messages (client);
938 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
939 "Transmitted %u/%u bytes to client %p\n",
942 client->client_handle);
948 * Task run to check for messages that need to be sent to a client.
950 * @param client a ClientList, containing the client and any messages to be sent to it
953 process_pending_messages (struct ClientList *client)
955 if ((client->pending_head == NULL) || (client->transmit_handle != NULL))
957 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
958 "Not asking for transmission to %p now: %s\n",
959 client->client_handle,
960 client->pending_head ==
961 NULL ? "no more messages" : "request already pending");
964 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
965 "Asking for transmission of %u bytes to client %p\n",
966 ntohs (client->pending_head->msg->size), client->client_handle);
967 client->transmit_handle =
968 GNUNET_SERVER_notify_transmit_ready (client->client_handle,
969 ntohs (client->pending_head->
971 GNUNET_TIME_UNIT_FOREVER_REL,
972 &send_reply_to_client, client);
977 * Closure for #forward_reply()
979 struct ForwardReplyContext
983 * Actual message to send to matching clients.
985 struct PendingMessage *pm;
995 enum GNUNET_BLOCK_Type type;
998 * Number of bytes in data.
1003 * Do we need to copy @a pm because it was already used?
1011 * Iterator over hash map entries that send a given reply to
1012 * each of the matching clients. With some tricky recycling
1015 * @param cls the 'struct ForwardReplyContext'
1016 * @param key current key
1017 * @param value value in the hash map, a ClientQueryRecord
1018 * @return #GNUNET_YES (we should continue to iterate),
1019 * if the result is mal-formed, #GNUNET_NO
1022 forward_reply (void *cls,
1023 const struct GNUNET_HashCode *key,
1026 struct ForwardReplyContext *frc = cls;
1027 struct ClientQueryRecord *record = value;
1028 struct PendingMessage *pm;
1029 struct GNUNET_DHT_ClientResultMessage *reply;
1030 enum GNUNET_BLOCK_EvaluationResult eval;
1032 struct GNUNET_HashCode ch;
1035 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG,
1036 "R5N CLIENT-RESULT %s\n",
1037 GNUNET_h2s_full (key));
1038 if ((record->type != GNUNET_BLOCK_TYPE_ANY) && (record->type != frc->type))
1040 LOG (GNUNET_ERROR_TYPE_DEBUG,
1041 "Record type missmatch, not passing request for key %s to local client\n",
1043 GNUNET_STATISTICS_update (GDS_stats,
1045 ("# Key match, type mismatches in REPLY to CLIENT"),
1047 return GNUNET_YES; /* type mismatch */
1049 GNUNET_CRYPTO_hash (frc->data, frc->data_size, &ch);
1050 for (i = 0; i < record->seen_replies_count; i++)
1051 if (0 == memcmp (&record->seen_replies[i], &ch, sizeof (struct GNUNET_HashCode)))
1053 LOG (GNUNET_ERROR_TYPE_DEBUG,
1054 "Duplicate reply, not passing request for key %s to local client\n",
1056 GNUNET_STATISTICS_update (GDS_stats,
1058 ("# Duplicate REPLIES to CLIENT request dropped"),
1060 return GNUNET_YES; /* duplicate */
1063 GNUNET_BLOCK_evaluate (GDS_block_context,
1065 GNUNET_BLOCK_EO_NONE,
1070 record->xquery_size,
1073 LOG (GNUNET_ERROR_TYPE_DEBUG,
1074 "Evaluation result is %d for key %s for local client's query\n",
1079 case GNUNET_BLOCK_EVALUATION_OK_LAST:
1080 do_free = GNUNET_YES;
1082 case GNUNET_BLOCK_EVALUATION_OK_MORE:
1083 GNUNET_array_append (record->seen_replies, record->seen_replies_count, ch);
1084 do_free = GNUNET_NO;
1086 case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
1087 /* should be impossible to encounter here */
1090 case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
1091 GNUNET_break_op (0);
1093 case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
1096 case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
1099 case GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT:
1101 case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
1102 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1103 _("Unsupported block type (%u) in request!\n"), record->type);
1109 if (GNUNET_NO == frc->do_copy)
1111 /* first time, we can use the original data */
1113 frc->do_copy = GNUNET_YES;
1117 /* two clients waiting for same reply, must copy for queueing */
1118 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
1119 ntohs (frc->pm->msg->size));
1120 memcpy (pm, frc->pm,
1121 sizeof (struct PendingMessage) + ntohs (frc->pm->msg->size));
1122 pm->next = pm->prev = NULL;
1123 pm->msg = (struct GNUNET_MessageHeader *) &pm[1];
1125 GNUNET_STATISTICS_update (GDS_stats,
1126 gettext_noop ("# RESULTS queued for clients"), 1,
1128 reply = (struct GNUNET_DHT_ClientResultMessage *) &pm[1];
1129 reply->unique_id = record->unique_id;
1130 LOG (GNUNET_ERROR_TYPE_DEBUG,
1131 "Queueing reply to query %s for client %p\n",
1133 record->client->client_handle);
1134 add_pending_message (record->client, pm);
1135 if (GNUNET_YES == do_free)
1136 remove_client_records (record->client, key, record);
1142 * Handle a reply we've received from another peer. If the reply
1143 * matches any of our pending queries, forward it to the respective
1146 * @param expiration when will the reply expire
1147 * @param key the query this reply is for
1148 * @param get_path_length number of peers in @a get_path
1149 * @param get_path path the reply took on get
1150 * @param put_path_length number of peers in @a put_path
1151 * @param put_path path the reply took on put
1152 * @param type type of the reply
1153 * @param data_size number of bytes in @a data
1154 * @param data application payload data
1157 GDS_CLIENTS_handle_reply (struct GNUNET_TIME_Absolute expiration,
1158 const struct GNUNET_HashCode *key,
1159 unsigned int get_path_length,
1160 const struct GNUNET_PeerIdentity *get_path,
1161 unsigned int put_path_length,
1162 const struct GNUNET_PeerIdentity *put_path,
1163 enum GNUNET_BLOCK_Type type, size_t data_size,
1166 struct ForwardReplyContext frc;
1167 struct PendingMessage *pm;
1168 struct GNUNET_DHT_ClientResultMessage *reply;
1169 struct GNUNET_PeerIdentity *paths;
1172 if (NULL == GNUNET_CONTAINER_multihashmap_get (forward_map, key))
1174 LOG (GNUNET_ERROR_TYPE_DEBUG,
1175 "No matching client for reply for key %s\n",
1177 GNUNET_STATISTICS_update (GDS_stats,
1179 ("# REPLIES ignored for CLIENTS (no match)"), 1,
1181 return; /* no matching request, fast exit! */
1184 sizeof (struct GNUNET_DHT_ClientResultMessage) + data_size +
1185 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity);
1186 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1191 LOG (GNUNET_ERROR_TYPE_DEBUG,
1192 "Forwarding reply for key %s to client\n",
1195 pm = GNUNET_malloc (msize + sizeof (struct PendingMessage));
1196 reply = (struct GNUNET_DHT_ClientResultMessage *) &pm[1];
1197 pm->msg = &reply->header;
1198 reply->header.size = htons ((uint16_t) msize);
1199 reply->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_CLIENT_RESULT);
1200 reply->type = htonl (type);
1201 reply->get_path_length = htonl (get_path_length);
1202 reply->put_path_length = htonl (put_path_length);
1203 reply->unique_id = 0; /* filled in later */
1204 reply->expiration = GNUNET_TIME_absolute_hton (expiration);
1206 paths = (struct GNUNET_PeerIdentity *) &reply[1];
1207 memcpy (paths, put_path,
1208 sizeof (struct GNUNET_PeerIdentity) * put_path_length);
1209 memcpy (&paths[put_path_length], get_path,
1210 sizeof (struct GNUNET_PeerIdentity) * get_path_length);
1211 memcpy (&paths[get_path_length + put_path_length], data, data_size);
1212 frc.do_copy = GNUNET_NO;
1215 frc.data_size = data_size;
1217 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map,
1222 if (GNUNET_NO == frc.do_copy)
1224 /* did not match any of the requests, free! */
1225 GNUNET_STATISTICS_update (GDS_stats,
1227 ("# REPLIES ignored for CLIENTS (no match)"), 1,
1235 * Check if some client is monitoring GET messages and notify
1236 * them in that case.
1238 * @param options Options, for instance RecordRoute, DemultiplexEverywhere.
1239 * @param type The type of data in the request.
1240 * @param hop_count Hop count so far.
1241 * @param path_length number of entries in path (or 0 if not recorded).
1242 * @param path peers on the GET path (or NULL if not recorded).
1243 * @param desired_replication_level Desired replication level.
1244 * @param key Key of the requested data.
1247 GDS_CLIENTS_process_get (uint32_t options,
1248 enum GNUNET_BLOCK_Type type,
1250 uint32_t desired_replication_level,
1251 unsigned int path_length,
1252 const struct GNUNET_PeerIdentity *path,
1253 const struct GNUNET_HashCode * key)
1255 struct ClientMonitorRecord *m;
1256 struct ClientList **cl;
1257 unsigned int cl_size;
1261 for (m = monitor_head; NULL != m; m = m->next)
1263 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1265 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1267 struct PendingMessage *pm;
1268 struct GNUNET_DHT_MonitorGetMessage *mmsg;
1269 struct GNUNET_PeerIdentity *msg_path;
1273 /* Don't send duplicates */
1274 for (i = 0; i < cl_size; i++)
1275 if (cl[i] == m->client)
1279 GNUNET_array_append (cl, cl_size, m->client);
1281 msize = path_length * sizeof (struct GNUNET_PeerIdentity);
1282 msize += sizeof (struct GNUNET_DHT_MonitorGetMessage);
1283 msize += sizeof (struct PendingMessage);
1284 pm = GNUNET_malloc (msize);
1285 mmsg = (struct GNUNET_DHT_MonitorGetMessage *) &pm[1];
1286 pm->msg = &mmsg->header;
1287 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1288 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_GET);
1289 mmsg->options = htonl(options);
1290 mmsg->type = htonl(type);
1291 mmsg->hop_count = htonl(hop_count);
1292 mmsg->desired_replication_level = htonl(desired_replication_level);
1293 mmsg->get_path_length = htonl(path_length);
1294 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1295 msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1296 if (path_length > 0)
1297 memcpy (msg_path, path,
1298 path_length * sizeof (struct GNUNET_PeerIdentity));
1299 add_pending_message (m->client, pm);
1302 GNUNET_free_non_null (cl);
1307 * Check if some client is monitoring GET RESP messages and notify
1308 * them in that case.
1310 * @param type The type of data in the result.
1311 * @param get_path Peers on GET path (or NULL if not recorded).
1312 * @param get_path_length number of entries in get_path.
1313 * @param put_path peers on the PUT path (or NULL if not recorded).
1314 * @param put_path_length number of entries in get_path.
1315 * @param exp Expiration time of the data.
1316 * @param key Key of the data.
1317 * @param data Pointer to the result data.
1318 * @param size Number of bytes in @a data.
1321 GDS_CLIENTS_process_get_resp (enum GNUNET_BLOCK_Type type,
1322 const struct GNUNET_PeerIdentity *get_path,
1323 unsigned int get_path_length,
1324 const struct GNUNET_PeerIdentity *put_path,
1325 unsigned int put_path_length,
1326 struct GNUNET_TIME_Absolute exp,
1327 const struct GNUNET_HashCode * key,
1331 struct ClientMonitorRecord *m;
1332 struct ClientList **cl;
1333 unsigned int cl_size;
1337 for (m = monitor_head; NULL != m; m = m->next)
1339 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1341 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1343 struct PendingMessage *pm;
1344 struct GNUNET_DHT_MonitorGetRespMessage *mmsg;
1345 struct GNUNET_PeerIdentity *path;
1349 /* Don't send duplicates */
1350 for (i = 0; i < cl_size; i++)
1351 if (cl[i] == m->client)
1355 GNUNET_array_append (cl, cl_size, m->client);
1358 msize += (get_path_length + put_path_length)
1359 * sizeof (struct GNUNET_PeerIdentity);
1360 msize += sizeof (struct GNUNET_DHT_MonitorGetRespMessage);
1361 msize += sizeof (struct PendingMessage);
1362 pm = GNUNET_malloc (msize);
1363 mmsg = (struct GNUNET_DHT_MonitorGetRespMessage *) &pm[1];
1364 pm->msg = (struct GNUNET_MessageHeader *) mmsg;
1365 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1366 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_GET_RESP);
1367 mmsg->type = htonl(type);
1368 mmsg->put_path_length = htonl(put_path_length);
1369 mmsg->get_path_length = htonl(get_path_length);
1370 path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1371 if (put_path_length > 0)
1373 memcpy (path, put_path,
1374 put_path_length * sizeof (struct GNUNET_PeerIdentity));
1375 path = &path[put_path_length];
1377 if (get_path_length > 0)
1378 memcpy (path, get_path,
1379 get_path_length * sizeof (struct GNUNET_PeerIdentity));
1380 mmsg->expiration_time = GNUNET_TIME_absolute_hton(exp);
1381 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1383 memcpy (&path[get_path_length], data, size);
1384 add_pending_message (m->client, pm);
1387 GNUNET_free_non_null (cl);
1392 * Check if some client is monitoring PUT messages and notify
1393 * them in that case.
1395 * @param options Options, for instance RecordRoute, DemultiplexEverywhere.
1396 * @param type The type of data in the request.
1397 * @param hop_count Hop count so far.
1398 * @param path_length number of entries in path (or 0 if not recorded).
1399 * @param path peers on the PUT path (or NULL if not recorded).
1400 * @param desired_replication_level Desired replication level.
1401 * @param exp Expiration time of the data.
1402 * @param key Key under which data is to be stored.
1403 * @param data Pointer to the data carried.
1404 * @param size Number of bytes in data.
1407 GDS_CLIENTS_process_put (uint32_t options,
1408 enum GNUNET_BLOCK_Type type,
1410 uint32_t desired_replication_level,
1411 unsigned int path_length,
1412 const struct GNUNET_PeerIdentity *path,
1413 struct GNUNET_TIME_Absolute exp,
1414 const struct GNUNET_HashCode * key,
1418 struct ClientMonitorRecord *m;
1419 struct ClientList **cl;
1420 unsigned int cl_size;
1424 for (m = monitor_head; NULL != m; m = m->next)
1426 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1428 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1430 struct PendingMessage *pm;
1431 struct GNUNET_DHT_MonitorPutMessage *mmsg;
1432 struct GNUNET_PeerIdentity *msg_path;
1436 /* Don't send duplicates */
1437 for (i = 0; i < cl_size; i++)
1438 if (cl[i] == m->client)
1442 GNUNET_array_append (cl, cl_size, m->client);
1445 msize += path_length * sizeof (struct GNUNET_PeerIdentity);
1446 msize += sizeof (struct GNUNET_DHT_MonitorPutMessage);
1447 msize += sizeof (struct PendingMessage);
1448 pm = GNUNET_malloc (msize);
1449 mmsg = (struct GNUNET_DHT_MonitorPutMessage *) &pm[1];
1450 pm->msg = (struct GNUNET_MessageHeader *) mmsg;
1451 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1452 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_PUT);
1453 mmsg->options = htonl(options);
1454 mmsg->type = htonl(type);
1455 mmsg->hop_count = htonl(hop_count);
1456 mmsg->desired_replication_level = htonl(desired_replication_level);
1457 mmsg->put_path_length = htonl(path_length);
1458 msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1459 if (path_length > 0)
1463 path_length * sizeof (struct GNUNET_PeerIdentity));
1465 mmsg->expiration_time = GNUNET_TIME_absolute_hton(exp);
1466 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1468 memcpy (&msg_path[path_length], data, size);
1469 add_pending_message (m->client, pm);
1472 GNUNET_free_non_null (cl);
1477 * Initialize client subsystem.
1479 * @param server the initialized server
1484 static struct GNUNET_SERVER_MessageHandler plugin_handlers[] = {
1485 {&handle_dht_local_put, NULL,
1486 GNUNET_MESSAGE_TYPE_DHT_CLIENT_PUT, 0},
1487 {&handle_dht_local_get, NULL,
1488 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET, 0},
1489 {&handle_dht_local_get_stop, NULL,
1490 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET_STOP,
1491 sizeof (struct GNUNET_DHT_ClientGetStopMessage)},
1492 {&handle_dht_local_monitor, NULL,
1493 GNUNET_MESSAGE_TYPE_DHT_MONITOR_START,
1494 sizeof (struct GNUNET_DHT_MonitorStartStopMessage)},
1495 {&handle_dht_local_monitor_stop, NULL,
1496 GNUNET_MESSAGE_TYPE_DHT_MONITOR_STOP,
1497 sizeof (struct GNUNET_DHT_MonitorStartStopMessage)},
1498 {&handle_dht_local_get_result_seen, NULL,
1499 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET_RESULTS_KNOWN, 0},
1503 forward_map = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
1504 retry_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1505 GNUNET_SERVER_resume (GDS_server);
1506 GNUNET_SERVER_add_handlers (GDS_server,
1508 GNUNET_SERVER_disconnect_notify (GDS_server,
1509 &handle_client_disconnect,
1515 * Shutdown client subsystem.
1520 GNUNET_assert (client_head == NULL);
1521 GNUNET_assert (client_tail == NULL);
1522 if (NULL != retry_task)
1524 GNUNET_SCHEDULER_cancel (retry_task);
1527 if (NULL != retry_heap)
1529 GNUNET_assert (0 == GNUNET_CONTAINER_heap_get_size (retry_heap));
1530 GNUNET_CONTAINER_heap_destroy (retry_heap);
1533 if (NULL != forward_map)
1535 GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (forward_map));
1536 GNUNET_CONTAINER_multihashmap_destroy (forward_map);
1541 /* end of gnunet-service-dht_clients.c */