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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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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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 * Linked list of messages to send to clients.
45 * Pointer to next item in the list
47 struct PendingMessage *next;
50 * Pointer to previous item in the list
52 struct PendingMessage *prev;
55 * Actual message to be sent, allocated at the end of the struct:
56 * // msg = (cast) &pm[1];
57 * // memcpy (&pm[1], data, len);
59 const struct GNUNET_MessageHeader *msg;
65 * Struct containing information about a client,
66 * handle to connect to it, and any pending messages
67 * that need to be sent to it.
72 * Linked list of active clients
74 struct ClientList *next;
77 * Linked list of active clients
79 struct ClientList *prev;
82 * The handle to this client
84 struct GNUNET_SERVER_Client *client_handle;
87 * Handle to the current transmission request, NULL
90 struct GNUNET_SERVER_TransmitHandle *transmit_handle;
93 * Linked list of pending messages for this client
95 struct PendingMessage *pending_head;
98 * Tail of linked list of pending messages for this client
100 struct PendingMessage *pending_tail;
106 * Entry in the DHT routing table for a client's GET request.
108 struct ClientQueryRecord
112 * The key this request was about
114 struct GNUNET_HashCode key;
117 * Client responsible for the request.
119 struct ClientList *client;
122 * Extended query (see gnunet_block_lib.h), allocated at the end of this struct.
127 * Replies we have already seen for this request.
129 struct GNUNET_HashCode *seen_replies;
132 * Pointer to this nodes heap location in the retry-heap (for fast removal)
134 struct GNUNET_CONTAINER_HeapNode *hnode;
137 * What's the delay between re-try operations that we currently use for this
140 struct GNUNET_TIME_Relative retry_frequency;
143 * What's the next time we should re-try this request?
145 struct GNUNET_TIME_Absolute retry_time;
148 * The unique identifier of this request
153 * Number of bytes in xquery.
158 * Number of entries in 'seen_replies'.
160 unsigned int seen_replies_count;
163 * Desired replication level
165 uint32_t replication;
168 * Any message options for this request
170 uint32_t msg_options;
173 * The type for the data for the GET request.
175 enum GNUNET_BLOCK_Type type;
181 * Struct containing paremeters of monitoring requests.
183 struct ClientMonitorRecord
187 * Next element in DLL.
189 struct ClientMonitorRecord *next;
192 * Previous element in DLL.
194 struct ClientMonitorRecord *prev;
197 * Type of blocks that are of interest
199 enum GNUNET_BLOCK_Type type;
202 * Key of data of interest, NULL for all.
204 struct GNUNET_HashCode *key;
207 * Flag whether to notify about GET messages.
212 * Flag whether to notify about GET_REPONSE messages.
217 * Flag whether to notify about PUT messages.
222 * Client to notify of these requests.
224 struct ClientList *client;
229 * List of active clients.
231 static struct ClientList *client_head;
234 * List of active clients.
236 static struct ClientList *client_tail;
239 * List of active monitoring requests.
241 static struct ClientMonitorRecord *monitor_head;
244 * List of active monitoring requests.
246 static struct ClientMonitorRecord *monitor_tail;
249 * Hashmap for fast key based lookup, maps keys to 'struct ClientQueryRecord' entries.
251 static struct GNUNET_CONTAINER_MultiHashMap *forward_map;
254 * Heap with all of our client's request, sorted by retry time (earliest on top).
256 static struct GNUNET_CONTAINER_Heap *retry_heap;
259 * Task that re-transmits requests (using retry_heap).
261 static GNUNET_SCHEDULER_TaskIdentifier retry_task;
265 * Task run to check for messages that need to be sent to a client.
267 * @param client a ClientList, containing the client and any messages to be sent to it
270 process_pending_messages (struct ClientList *client);
274 * Add a PendingMessage to the clients list of messages to be sent
276 * @param client the active client to send the message to
277 * @param pending_message the actual message to send
280 add_pending_message (struct ClientList *client,
281 struct PendingMessage *pending_message)
283 GNUNET_CONTAINER_DLL_insert_tail (client->pending_head, client->pending_tail,
285 process_pending_messages (client);
290 * Find a client if it exists, add it otherwise.
292 * @param client the server handle to the client
294 * @return the client if found, a new client otherwise
296 static struct ClientList *
297 find_active_client (struct GNUNET_SERVER_Client *client)
299 struct ClientList *pos = client_head;
300 struct ClientList *ret;
304 if (pos->client_handle == client)
308 ret = GNUNET_malloc (sizeof (struct ClientList));
309 ret->client_handle = client;
310 GNUNET_CONTAINER_DLL_insert (client_head, client_tail, ret);
316 * Iterator over hash map entries that frees all entries
317 * associated with the given client.
319 * @param cls client to search for in source routes
320 * @param key current key code (ignored)
321 * @param value value in the hash map, a ClientQueryRecord
322 * @return GNUNET_YES (we should continue to iterate)
325 remove_client_records (void *cls, const struct GNUNET_HashCode * key, void *value)
327 struct ClientList *client = cls;
328 struct ClientQueryRecord *record = value;
330 if (record->client != client)
332 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
333 "Removing client %p's record for key %s\n", client,
335 GNUNET_assert (GNUNET_YES ==
336 GNUNET_CONTAINER_multihashmap_remove (forward_map, key,
338 if (NULL != record->hnode)
339 GNUNET_CONTAINER_heap_remove_node (record->hnode);
340 GNUNET_array_grow (record->seen_replies, record->seen_replies_count, 0);
341 GNUNET_free (record);
347 * Functions with this signature are called whenever a client
348 * is disconnected on the network level.
350 * @param cls closure (NULL for dht)
351 * @param client identification of the client; NULL
352 * for the last call when the server is destroyed
355 handle_client_disconnect (void *cls, struct GNUNET_SERVER_Client *client)
357 struct ClientList *pos;
358 struct PendingMessage *reply;
359 struct ClientMonitorRecord *monitor;
361 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Local client %p disconnects\n", client);
362 pos = find_active_client (client);
363 GNUNET_CONTAINER_DLL_remove (client_head, client_tail, pos);
364 if (pos->transmit_handle != NULL)
365 GNUNET_SERVER_notify_transmit_ready_cancel (pos->transmit_handle);
366 while (NULL != (reply = pos->pending_head))
368 GNUNET_CONTAINER_DLL_remove (pos->pending_head, pos->pending_tail, reply);
371 monitor = monitor_head;
372 while (NULL != monitor)
374 if (monitor->client == pos)
376 struct ClientMonitorRecord *next;
378 GNUNET_free_non_null (monitor->key);
379 next = monitor->next;
380 GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, monitor);
381 GNUNET_free (monitor);
385 monitor = monitor->next;
387 GNUNET_CONTAINER_multihashmap_iterate (forward_map, &remove_client_records,
394 * Route the given request via the DHT. This includes updating
395 * the bloom filter and retransmission times, building the P2P
396 * message and initiating the routing operation.
399 transmit_request (struct ClientQueryRecord *cqr)
401 int32_t reply_bf_mutator;
402 struct GNUNET_CONTAINER_BloomFilter *reply_bf;
403 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
405 GNUNET_STATISTICS_update (GDS_stats,
407 ("# GET requests from clients injected"), 1,
410 (int32_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
413 GNUNET_BLOCK_construct_bloomfilter (reply_bf_mutator, cqr->seen_replies,
414 cqr->seen_replies_count);
416 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
417 GNUNET_CONSTANTS_BLOOMFILTER_K);
418 GDS_NEIGHBOURS_handle_get (cqr->type, cqr->msg_options, cqr->replication,
420 &cqr->key, cqr->xquery, cqr->xquery_size, reply_bf,
421 reply_bf_mutator, peer_bf);
422 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
423 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
425 /* exponential back-off for retries, max 1h */
426 cqr->retry_frequency =
427 GNUNET_TIME_relative_min (GNUNET_TIME_UNIT_HOURS,
428 GNUNET_TIME_relative_multiply
429 (cqr->retry_frequency, 2));
430 cqr->retry_time = GNUNET_TIME_relative_to_absolute (cqr->retry_frequency);
435 * Task that looks at the 'retry_heap' and transmits all of the requests
436 * on the heap that are ready for transmission. Then re-schedules
437 * itself (unless the heap is empty).
440 * @param tc scheduler context
443 transmit_next_request_task (void *cls,
444 const struct GNUNET_SCHEDULER_TaskContext *tc)
446 struct ClientQueryRecord *cqr;
447 struct GNUNET_TIME_Relative delay;
449 retry_task = GNUNET_SCHEDULER_NO_TASK;
450 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
452 while (NULL != (cqr = GNUNET_CONTAINER_heap_remove_root (retry_heap)))
455 delay = GNUNET_TIME_absolute_get_remaining (cqr->retry_time);
456 if (delay.rel_value > 0)
459 GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
460 cqr->retry_time.abs_value);
462 GNUNET_SCHEDULER_add_delayed (delay, &transmit_next_request_task,
466 transmit_request (cqr);
468 GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
469 cqr->retry_time.abs_value);
475 * Handler for PUT messages.
477 * @param cls closure for the service
478 * @param client the client we received this message from
479 * @param message the actual message received
482 handle_dht_local_put (void *cls, struct GNUNET_SERVER_Client *client,
483 const struct GNUNET_MessageHeader *message)
485 const struct GNUNET_DHT_ClientPutMessage *dht_msg;
486 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
488 struct PendingMessage *pm;
489 struct GNUNET_DHT_ClientPutConfirmationMessage *conf;
491 size = ntohs (message->size);
492 if (size < sizeof (struct GNUNET_DHT_ClientPutMessage))
495 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
498 GNUNET_STATISTICS_update (GDS_stats,
500 ("# PUT requests received from clients"), 1,
502 dht_msg = (const struct GNUNET_DHT_ClientPutMessage *) message;
503 /* give to local clients */
504 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
505 "Handling local PUT of %u-bytes for query %s\n",
506 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
507 GNUNET_h2s (&dht_msg->key));
508 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
509 &dht_msg->key, 0, NULL, 0, NULL,
510 ntohl (dht_msg->type),
511 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
514 GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
515 &dht_msg->key, 0, NULL, ntohl (dht_msg->type),
516 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
518 /* route to other peers */
520 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
521 GNUNET_CONSTANTS_BLOOMFILTER_K);
522 GDS_NEIGHBOURS_handle_put (ntohl (dht_msg->type), ntohl (dht_msg->options),
523 ntohl (dht_msg->desired_replication_level),
524 GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
526 peer_bf, &dht_msg->key, 0, NULL, &dht_msg[1],
528 sizeof (struct GNUNET_DHT_ClientPutMessage));
529 GDS_CLIENTS_process_put (ntohl (dht_msg->options),
530 ntohl (dht_msg->type),
532 ntohl (dht_msg->desired_replication_level),
534 GDS_NEIGHBOURS_get_id(),
535 GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
538 size - sizeof (struct GNUNET_DHT_ClientPutMessage));
539 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
540 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
541 sizeof (struct GNUNET_DHT_ClientPutConfirmationMessage));
542 conf = (struct GNUNET_DHT_ClientPutConfirmationMessage *) &pm[1];
543 conf->header.size = htons (sizeof (struct GNUNET_DHT_ClientPutConfirmationMessage));
544 conf->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_CLIENT_PUT_OK);
545 conf->reserved = htonl (0);
546 conf->unique_id = dht_msg->unique_id;
547 pm->msg = &conf->header;
548 add_pending_message (find_active_client (client), pm);
549 GNUNET_SERVER_receive_done (client, GNUNET_OK);
554 * Handler for DHT GET messages from the client.
556 * @param cls closure for the service
557 * @param client the client we received this message from
558 * @param message the actual message received
561 handle_dht_local_get (void *cls, struct GNUNET_SERVER_Client *client,
562 const struct GNUNET_MessageHeader *message)
564 const struct GNUNET_DHT_ClientGetMessage *get;
565 struct ClientQueryRecord *cqr;
570 size = ntohs (message->size);
571 if (size < sizeof (struct GNUNET_DHT_ClientGetMessage))
574 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
577 xquery_size = size - sizeof (struct GNUNET_DHT_ClientGetMessage);
578 get = (const struct GNUNET_DHT_ClientGetMessage *) message;
579 xquery = (const char *) &get[1];
580 GNUNET_STATISTICS_update (GDS_stats,
582 ("# GET requests received from clients"), 1,
584 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
585 "Received request for %s from local client %p\n",
586 GNUNET_h2s (&get->key), client);
587 cqr = GNUNET_malloc (sizeof (struct ClientQueryRecord) + xquery_size);
589 cqr->client = find_active_client (client);
590 cqr->xquery = (void *) &cqr[1];
591 memcpy (&cqr[1], xquery, xquery_size);
592 cqr->hnode = GNUNET_CONTAINER_heap_insert (retry_heap, cqr, 0);
593 cqr->retry_frequency = GNUNET_TIME_UNIT_MILLISECONDS;
594 cqr->retry_time = GNUNET_TIME_absolute_get ();
595 cqr->unique_id = get->unique_id;
596 cqr->xquery_size = xquery_size;
597 cqr->replication = ntohl (get->desired_replication_level);
598 cqr->msg_options = ntohl (get->options);
599 cqr->type = ntohl (get->type);
600 // FIXME use cqr->key, set multihashmap create to GNUNET_YES
601 GNUNET_CONTAINER_multihashmap_put (forward_map, &get->key, cqr,
602 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
603 GDS_CLIENTS_process_get (ntohl (get->options),
606 ntohl (get->desired_replication_level),
608 GDS_NEIGHBOURS_get_id(),
610 /* start remote requests */
611 if (GNUNET_SCHEDULER_NO_TASK != retry_task)
612 GNUNET_SCHEDULER_cancel (retry_task);
613 retry_task = GNUNET_SCHEDULER_add_now (&transmit_next_request_task, NULL);
614 /* perform local lookup */
615 GDS_DATACACHE_handle_get (&get->key, cqr->type, cqr->xquery, xquery_size,
617 GNUNET_SERVER_receive_done (client, GNUNET_OK);
622 * Closure for 'find_by_unique_id'.
624 struct FindByUniqueIdContext
627 * Where to store the result, if found.
629 struct ClientQueryRecord *cqr;
636 * Function called for each existing DHT record for the given
637 * query. Checks if it matches the UID given in the closure
638 * and if so returns the entry as a result.
640 * @param cls the search context
641 * @param key query for the lookup (not used)
642 * @param value the 'struct ClientQueryRecord'
643 * @return GNUNET_YES to continue iteration (result not yet found)
646 find_by_unique_id (void *cls,
647 const struct GNUNET_HashCode *key,
650 struct FindByUniqueIdContext *fui_ctx = cls;
651 struct ClientQueryRecord *cqr = value;
653 if (cqr->unique_id != fui_ctx->unique_id)
661 * Handler for "GET result seen" messages from the client.
663 * @param cls closure for the service
664 * @param client the client we received this message from
665 * @param message the actual message received
668 handle_dht_local_get_result_seen (void *cls, struct GNUNET_SERVER_Client *client,
669 const struct GNUNET_MessageHeader *message)
671 const struct GNUNET_DHT_ClientGetResultSeenMessage *seen;
673 unsigned int hash_count;
674 unsigned int old_count;
675 const struct GNUNET_HashCode *hc;
676 struct FindByUniqueIdContext fui_ctx;
677 struct ClientQueryRecord *cqr;
679 size = ntohs (message->size);
680 if (size < sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage))
683 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
686 seen = (const struct GNUNET_DHT_ClientGetResultSeenMessage *) message;
687 hash_count = (size - sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage)) / sizeof (struct GNUNET_HashCode);
688 if (size != sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage) + hash_count * sizeof (struct GNUNET_HashCode))
691 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
694 hc = (const struct GNUNET_HashCode*) &seen[1];
695 fui_ctx.unique_id = seen->unique_id;
697 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map,
701 if (NULL == (cqr = fui_ctx.cqr))
704 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
707 /* finally, update 'seen' list */
708 old_count = cqr->seen_replies_count;
709 GNUNET_array_grow (cqr->seen_replies,
710 cqr->seen_replies_count,
711 cqr->seen_replies_count + hash_count);
712 memcpy (&cqr->seen_replies[old_count],
714 sizeof (struct GNUNET_HashCode) * hash_count);
719 * Closure for 'remove_by_unique_id'.
721 struct RemoveByUniqueIdContext
724 * Client that issued the removal request.
726 struct ClientList *client;
729 * Unique ID of the request.
736 * Iterator over hash map entries that frees all entries
737 * that match the given client and unique ID.
739 * @param cls unique ID and client to search for in source routes
740 * @param key current key code
741 * @param value value in the hash map, a ClientQueryRecord
742 * @return GNUNET_YES (we should continue to iterate)
745 remove_by_unique_id (void *cls, const struct GNUNET_HashCode * key, void *value)
747 const struct RemoveByUniqueIdContext *ctx = cls;
748 struct ClientQueryRecord *record = value;
750 if (record->unique_id != ctx->unique_id)
752 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
753 "Removing client %p's record for key %s (by unique id)\n",
754 ctx->client->client_handle, GNUNET_h2s (key));
755 return remove_client_records (ctx->client, key, record);
760 * Handler for any generic DHT stop messages, calls the appropriate handler
761 * depending on message type (if processed locally)
763 * @param cls closure for the service
764 * @param client the client we received this message from
765 * @param message the actual message received
769 handle_dht_local_get_stop (void *cls, struct GNUNET_SERVER_Client *client,
770 const struct GNUNET_MessageHeader *message)
772 const struct GNUNET_DHT_ClientGetStopMessage *dht_stop_msg =
773 (const struct GNUNET_DHT_ClientGetStopMessage *) message;
774 struct RemoveByUniqueIdContext ctx;
776 GNUNET_STATISTICS_update (GDS_stats,
778 ("# GET STOP requests received from clients"), 1,
780 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Client %p stopped request for key %s\n",
781 client, GNUNET_h2s (&dht_stop_msg->key));
782 ctx.client = find_active_client (client);
783 ctx.unique_id = dht_stop_msg->unique_id;
784 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, &dht_stop_msg->key,
785 &remove_by_unique_id, &ctx);
786 GNUNET_SERVER_receive_done (client, GNUNET_OK);
791 * Handler for monitor start messages
793 * @param cls closure for the service
794 * @param client the client we received this message from
795 * @param message the actual message received
799 handle_dht_local_monitor (void *cls, struct GNUNET_SERVER_Client *client,
800 const struct GNUNET_MessageHeader *message)
802 struct ClientMonitorRecord *r;
803 const struct GNUNET_DHT_MonitorStartStopMessage *msg;
805 msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
806 r = GNUNET_malloc (sizeof(struct ClientMonitorRecord));
808 r->client = find_active_client(client);
809 r->type = ntohl(msg->type);
810 r->get = ntohs(msg->get);
811 r->get_resp = ntohs(msg->get_resp);
812 r->put = ntohs(msg->put);
813 if (0 == ntohs(msg->filter_key))
817 r->key = GNUNET_malloc (sizeof (struct GNUNET_HashCode));
818 memcpy (r->key, &msg->key, sizeof (struct GNUNET_HashCode));
820 GNUNET_CONTAINER_DLL_insert (monitor_head, monitor_tail, r);
821 GNUNET_SERVER_receive_done (client, GNUNET_OK);
825 * Handler for monitor stop messages
827 * @param cls closure for the service
828 * @param client the client we received this message from
829 * @param message the actual message received
833 handle_dht_local_monitor_stop (void *cls, struct GNUNET_SERVER_Client *client,
834 const struct GNUNET_MessageHeader *message)
836 struct ClientMonitorRecord *r;
837 const struct GNUNET_DHT_MonitorStartStopMessage *msg;
840 msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
846 keys_match = (0 == ntohs(msg->filter_key));
849 keys_match = (0 != ntohs(msg->filter_key)
850 && !memcmp(r->key, &msg->key, sizeof(struct GNUNET_HashCode)));
852 if (find_active_client(client) == r->client
853 && ntohl(msg->type) == r->type
854 && r->get == msg->get
855 && r->get_resp == msg->get_resp
856 && r->put == msg->put
860 GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, r);
861 GNUNET_free_non_null (r->key);
863 GNUNET_SERVER_receive_done (client, GNUNET_OK);
864 return; /* Delete only ONE entry */
869 GNUNET_SERVER_receive_done (client, GNUNET_OK);
874 * Callback called as a result of issuing a GNUNET_SERVER_notify_transmit_ready
875 * request. A ClientList is passed as closure, take the head of the list
876 * and copy it into buf, which has the result of sending the message to the
879 * @param cls closure to this call
880 * @param size maximum number of bytes available to send
881 * @param buf where to copy the actual message to
883 * @return the number of bytes actually copied, 0 indicates failure
886 send_reply_to_client (void *cls, size_t size, void *buf)
888 struct ClientList *client = cls;
890 struct PendingMessage *reply;
894 client->transmit_handle = NULL;
897 /* client disconnected */
898 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
899 "Client %p disconnected, pending messages will be discarded\n",
900 client->client_handle);
904 while ((NULL != (reply = client->pending_head)) &&
905 (size >= off + (msize = ntohs (reply->msg->size))))
907 GNUNET_CONTAINER_DLL_remove (client->pending_head, client->pending_tail,
909 memcpy (&cbuf[off], reply->msg, msize);
911 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u bytes to client %p\n",
912 msize, client->client_handle);
915 process_pending_messages (client);
916 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitted %u/%u bytes to client %p\n",
917 (unsigned int) off, (unsigned int) size, client->client_handle);
923 * Task run to check for messages that need to be sent to a client.
925 * @param client a ClientList, containing the client and any messages to be sent to it
928 process_pending_messages (struct ClientList *client)
930 if ((client->pending_head == NULL) || (client->transmit_handle != NULL))
932 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
933 "Not asking for transmission to %p now: %s\n",
934 client->client_handle,
935 client->pending_head ==
936 NULL ? "no more messages" : "request already pending");
939 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
940 "Asking for transmission of %u bytes to client %p\n",
941 ntohs (client->pending_head->msg->size), client->client_handle);
942 client->transmit_handle =
943 GNUNET_SERVER_notify_transmit_ready (client->client_handle,
944 ntohs (client->pending_head->
946 GNUNET_TIME_UNIT_FOREVER_REL,
947 &send_reply_to_client, client);
952 * Closure for 'forward_reply'
954 struct ForwardReplyContext
958 * Actual message to send to matching clients.
960 struct PendingMessage *pm;
970 enum GNUNET_BLOCK_Type type;
973 * Number of bytes in data.
978 * Do we need to copy 'pm' because it was already used?
986 * Iterator over hash map entries that send a given reply to
987 * each of the matching clients. With some tricky recycling
990 * @param cls the 'struct ForwardReplyContext'
991 * @param key current key
992 * @param value value in the hash map, a ClientQueryRecord
993 * @return GNUNET_YES (we should continue to iterate),
994 * if the result is mal-formed, GNUNET_NO
997 forward_reply (void *cls, const struct GNUNET_HashCode * key, void *value)
999 struct ForwardReplyContext *frc = cls;
1000 struct ClientQueryRecord *record = value;
1001 struct PendingMessage *pm;
1002 struct GNUNET_DHT_ClientResultMessage *reply;
1003 enum GNUNET_BLOCK_EvaluationResult eval;
1005 struct GNUNET_HashCode ch;
1008 if ((record->type != GNUNET_BLOCK_TYPE_ANY) && (record->type != frc->type))
1010 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1011 "Record type missmatch, not passing request for key %s to local client\n",
1013 GNUNET_STATISTICS_update (GDS_stats,
1015 ("# Key match, type mismatches in REPLY to CLIENT"),
1017 return GNUNET_YES; /* type mismatch */
1019 GNUNET_CRYPTO_hash (frc->data, frc->data_size, &ch);
1020 for (i = 0; i < record->seen_replies_count; i++)
1021 if (0 == memcmp (&record->seen_replies[i], &ch, sizeof (struct GNUNET_HashCode)))
1023 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1024 "Duplicate reply, not passing request for key %s to local client\n",
1026 GNUNET_STATISTICS_update (GDS_stats,
1028 ("# Duplicate REPLIES to CLIENT request dropped"),
1030 return GNUNET_YES; /* duplicate */
1033 GNUNET_BLOCK_evaluate (GDS_block_context, record->type, key, NULL, 0,
1034 record->xquery, record->xquery_size, frc->data,
1036 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1037 "Evaluation result is %d for key %s for local client's query\n",
1038 (int) eval, GNUNET_h2s (key));
1041 case GNUNET_BLOCK_EVALUATION_OK_LAST:
1042 do_free = GNUNET_YES;
1044 case GNUNET_BLOCK_EVALUATION_OK_MORE:
1045 GNUNET_array_append (record->seen_replies, record->seen_replies_count, ch);
1046 do_free = GNUNET_NO;
1048 case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
1049 /* should be impossible to encounter here */
1052 case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
1053 GNUNET_break_op (0);
1055 case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
1058 case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
1061 case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
1062 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1063 _("Unsupported block type (%u) in request!\n"), record->type);
1069 if (GNUNET_NO == frc->do_copy)
1071 /* first time, we can use the original data */
1073 frc->do_copy = GNUNET_YES;
1077 /* two clients waiting for same reply, must copy for queueing */
1078 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
1079 ntohs (frc->pm->msg->size));
1080 memcpy (pm, frc->pm,
1081 sizeof (struct PendingMessage) + ntohs (frc->pm->msg->size));
1082 pm->next = pm->prev = NULL;
1083 pm->msg = (struct GNUNET_MessageHeader *) &pm[1];
1085 GNUNET_STATISTICS_update (GDS_stats,
1086 gettext_noop ("# RESULTS queued for clients"), 1,
1088 reply = (struct GNUNET_DHT_ClientResultMessage *) &pm[1];
1089 reply->unique_id = record->unique_id;
1090 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1091 "Queueing reply to query %s for client %p\n", GNUNET_h2s (key),
1092 record->client->client_handle);
1093 add_pending_message (record->client, pm);
1094 if (GNUNET_YES == do_free)
1095 remove_client_records (record->client, key, record);
1101 * Handle a reply we've received from another peer. If the reply
1102 * matches any of our pending queries, forward it to the respective
1105 * @param expiration when will the reply expire
1106 * @param key the query this reply is for
1107 * @param get_path_length number of peers in 'get_path'
1108 * @param get_path path the reply took on get
1109 * @param put_path_length number of peers in 'put_path'
1110 * @param put_path path the reply took on put
1111 * @param type type of the reply
1112 * @param data_size number of bytes in 'data'
1113 * @param data application payload data
1116 GDS_CLIENTS_handle_reply (struct GNUNET_TIME_Absolute expiration,
1117 const struct GNUNET_HashCode * key,
1118 unsigned int get_path_length,
1119 const struct GNUNET_PeerIdentity *get_path,
1120 unsigned int put_path_length,
1121 const struct GNUNET_PeerIdentity *put_path,
1122 enum GNUNET_BLOCK_Type type, size_t data_size,
1125 struct ForwardReplyContext frc;
1126 struct PendingMessage *pm;
1127 struct GNUNET_DHT_ClientResultMessage *reply;
1128 struct GNUNET_PeerIdentity *paths;
1131 if (NULL == GNUNET_CONTAINER_multihashmap_get (forward_map, key))
1133 GNUNET_STATISTICS_update (GDS_stats,
1135 ("# REPLIES ignored for CLIENTS (no match)"), 1,
1137 return; /* no matching request, fast exit! */
1140 sizeof (struct GNUNET_DHT_ClientResultMessage) + data_size +
1141 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity);
1142 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1144 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1145 _("Could not pass reply to client, message too big!\n"));
1148 pm = (struct PendingMessage *) GNUNET_malloc (msize +
1149 sizeof (struct PendingMessage));
1150 reply = (struct GNUNET_DHT_ClientResultMessage *) &pm[1];
1151 pm->msg = &reply->header;
1152 reply->header.size = htons ((uint16_t) msize);
1153 reply->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_CLIENT_RESULT);
1154 reply->type = htonl (type);
1155 reply->get_path_length = htonl (get_path_length);
1156 reply->put_path_length = htonl (put_path_length);
1157 reply->unique_id = 0; /* filled in later */
1158 reply->expiration = GNUNET_TIME_absolute_hton (expiration);
1160 paths = (struct GNUNET_PeerIdentity *) &reply[1];
1161 memcpy (paths, put_path,
1162 sizeof (struct GNUNET_PeerIdentity) * put_path_length);
1163 memcpy (&paths[put_path_length], get_path,
1164 sizeof (struct GNUNET_PeerIdentity) * get_path_length);
1165 memcpy (&paths[get_path_length + put_path_length], data, data_size);
1166 frc.do_copy = GNUNET_NO;
1169 frc.data_size = data_size;
1171 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, key, &forward_reply,
1173 if (GNUNET_NO == frc.do_copy)
1175 /* did not match any of the requests, free! */
1176 GNUNET_STATISTICS_update (GDS_stats,
1178 ("# REPLIES ignored for CLIENTS (no match)"), 1,
1186 * Check if some client is monitoring GET messages and notify
1187 * them in that case.
1189 * @param options Options, for instance RecordRoute, DemultiplexEverywhere.
1190 * @param type The type of data in the request.
1191 * @param hop_count Hop count so far.
1192 * @param path_length number of entries in path (or 0 if not recorded).
1193 * @param path peers on the GET path (or NULL if not recorded).
1194 * @param desired_replication_level Desired replication level.
1195 * @param key Key of the requested data.
1198 GDS_CLIENTS_process_get (uint32_t options,
1199 enum GNUNET_BLOCK_Type type,
1201 uint32_t desired_replication_level,
1202 unsigned int path_length,
1203 const struct GNUNET_PeerIdentity *path,
1204 const struct GNUNET_HashCode * key)
1206 struct ClientMonitorRecord *m;
1207 struct ClientList **cl;
1208 unsigned int cl_size;
1212 for (m = monitor_head; NULL != m; m = m->next)
1214 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1216 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1218 struct PendingMessage *pm;
1219 struct GNUNET_DHT_MonitorGetMessage *mmsg;
1220 struct GNUNET_PeerIdentity *msg_path;
1224 /* Don't send duplicates */
1225 for (i = 0; i < cl_size; i++)
1226 if (cl[i] == m->client)
1230 GNUNET_array_append (cl, cl_size, m->client);
1232 msize = path_length * sizeof (struct GNUNET_PeerIdentity);
1233 msize += sizeof (struct GNUNET_DHT_MonitorGetMessage);
1234 msize += sizeof (struct PendingMessage);
1235 pm = (struct PendingMessage *) GNUNET_malloc (msize);
1236 mmsg = (struct GNUNET_DHT_MonitorGetMessage *) &pm[1];
1237 pm->msg = &mmsg->header;
1238 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1239 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_GET);
1240 mmsg->options = htonl(options);
1241 mmsg->type = htonl(type);
1242 mmsg->hop_count = htonl(hop_count);
1243 mmsg->desired_replication_level = htonl(desired_replication_level);
1244 mmsg->get_path_length = htonl(path_length);
1245 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1246 msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1247 if (path_length > 0)
1248 memcpy (msg_path, path,
1249 path_length * sizeof (struct GNUNET_PeerIdentity));
1250 add_pending_message (m->client, pm);
1253 GNUNET_free_non_null (cl);
1258 * Check if some client is monitoring GET RESP messages and notify
1259 * them in that case.
1261 * @param type The type of data in the result.
1262 * @param get_path Peers on GET path (or NULL if not recorded).
1263 * @param get_path_length number of entries in get_path.
1264 * @param put_path peers on the PUT path (or NULL if not recorded).
1265 * @param put_path_length number of entries in get_path.
1266 * @param exp Expiration time of the data.
1267 * @param key Key of the data.
1268 * @param data Pointer to the result data.
1269 * @param size Number of bytes in data.
1272 GDS_CLIENTS_process_get_resp (enum GNUNET_BLOCK_Type type,
1273 const struct GNUNET_PeerIdentity *get_path,
1274 unsigned int get_path_length,
1275 const struct GNUNET_PeerIdentity *put_path,
1276 unsigned int put_path_length,
1277 struct GNUNET_TIME_Absolute exp,
1278 const struct GNUNET_HashCode * key,
1282 struct ClientMonitorRecord *m;
1283 struct ClientList **cl;
1284 unsigned int cl_size;
1288 for (m = monitor_head; NULL != m; m = m->next)
1290 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1292 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1294 struct PendingMessage *pm;
1295 struct GNUNET_DHT_MonitorGetRespMessage *mmsg;
1296 struct GNUNET_PeerIdentity *path;
1300 /* Don't send duplicates */
1301 for (i = 0; i < cl_size; i++)
1302 if (cl[i] == m->client)
1306 GNUNET_array_append (cl, cl_size, m->client);
1309 msize += (get_path_length + put_path_length)
1310 * sizeof (struct GNUNET_PeerIdentity);
1311 msize += sizeof (struct GNUNET_DHT_MonitorGetRespMessage);
1312 msize += sizeof (struct PendingMessage);
1313 pm = (struct PendingMessage *) GNUNET_malloc (msize);
1314 mmsg = (struct GNUNET_DHT_MonitorGetRespMessage *) &pm[1];
1315 pm->msg = (struct GNUNET_MessageHeader *) mmsg;
1316 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1317 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_GET_RESP);
1318 mmsg->type = htonl(type);
1319 mmsg->put_path_length = htonl(put_path_length);
1320 mmsg->get_path_length = htonl(get_path_length);
1321 path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1322 if (put_path_length > 0)
1324 memcpy (path, put_path,
1325 put_path_length * sizeof (struct GNUNET_PeerIdentity));
1326 path = &path[put_path_length];
1328 if (get_path_length > 0)
1329 memcpy (path, get_path,
1330 get_path_length * sizeof (struct GNUNET_PeerIdentity));
1331 mmsg->expiration_time = GNUNET_TIME_absolute_hton(exp);
1332 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1334 memcpy (&path[get_path_length], data, size);
1335 add_pending_message (m->client, pm);
1338 GNUNET_free_non_null (cl);
1343 * Check if some client is monitoring PUT messages and notify
1344 * them in that case.
1346 * @param options Options, for instance RecordRoute, DemultiplexEverywhere.
1347 * @param type The type of data in the request.
1348 * @param hop_count Hop count so far.
1349 * @param path_length number of entries in path (or 0 if not recorded).
1350 * @param path peers on the PUT path (or NULL if not recorded).
1351 * @param desired_replication_level Desired replication level.
1352 * @param exp Expiration time of the data.
1353 * @param key Key under which data is to be stored.
1354 * @param data Pointer to the data carried.
1355 * @param size Number of bytes in data.
1358 GDS_CLIENTS_process_put (uint32_t options,
1359 enum GNUNET_BLOCK_Type type,
1361 uint32_t desired_replication_level,
1362 unsigned int path_length,
1363 const struct GNUNET_PeerIdentity *path,
1364 struct GNUNET_TIME_Absolute exp,
1365 const struct GNUNET_HashCode * key,
1369 struct ClientMonitorRecord *m;
1370 struct ClientList **cl;
1371 unsigned int cl_size;
1375 for (m = monitor_head; NULL != m; m = m->next)
1377 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1379 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1381 struct PendingMessage *pm;
1382 struct GNUNET_DHT_MonitorPutMessage *mmsg;
1383 struct GNUNET_PeerIdentity *msg_path;
1387 /* Don't send duplicates */
1388 for (i = 0; i < cl_size; i++)
1389 if (cl[i] == m->client)
1393 GNUNET_array_append (cl, cl_size, m->client);
1396 msize += path_length * sizeof (struct GNUNET_PeerIdentity);
1397 msize += sizeof (struct GNUNET_DHT_MonitorPutMessage);
1398 msize += sizeof (struct PendingMessage);
1399 pm = (struct PendingMessage *) GNUNET_malloc (msize);
1400 mmsg = (struct GNUNET_DHT_MonitorPutMessage *) &pm[1];
1401 pm->msg = (struct GNUNET_MessageHeader *) mmsg;
1402 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1403 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_PUT);
1404 mmsg->options = htonl(options);
1405 mmsg->type = htonl(type);
1406 mmsg->hop_count = htonl(hop_count);
1407 mmsg->desired_replication_level = htonl(desired_replication_level);
1408 mmsg->put_path_length = htonl(path_length);
1409 msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1410 if (path_length > 0)
1412 memcpy (msg_path, path,
1413 path_length * sizeof (struct GNUNET_PeerIdentity));
1415 mmsg->expiration_time = GNUNET_TIME_absolute_hton(exp);
1416 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1418 memcpy (&msg_path[path_length], data, size);
1419 add_pending_message (m->client, pm);
1422 GNUNET_free_non_null (cl);
1427 * Initialize client subsystem.
1429 * @param server the initialized server
1432 GDS_CLIENTS_init (struct GNUNET_SERVER_Handle *server)
1434 static struct GNUNET_SERVER_MessageHandler plugin_handlers[] = {
1435 {&handle_dht_local_put, NULL,
1436 GNUNET_MESSAGE_TYPE_DHT_CLIENT_PUT, 0},
1437 {&handle_dht_local_get, NULL,
1438 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET, 0},
1439 {&handle_dht_local_get_stop, NULL,
1440 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET_STOP,
1441 sizeof (struct GNUNET_DHT_ClientGetStopMessage)},
1442 {&handle_dht_local_monitor, NULL,
1443 GNUNET_MESSAGE_TYPE_DHT_MONITOR_START,
1444 sizeof (struct GNUNET_DHT_MonitorStartStopMessage)},
1445 {&handle_dht_local_monitor_stop, NULL,
1446 GNUNET_MESSAGE_TYPE_DHT_MONITOR_STOP,
1447 sizeof (struct GNUNET_DHT_MonitorStartStopMessage)},
1448 {&handle_dht_local_get_result_seen, NULL,
1449 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET_RESULTS_KNOWN, 0},
1452 forward_map = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
1453 retry_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1454 GNUNET_SERVER_add_handlers (server, plugin_handlers);
1455 GNUNET_SERVER_disconnect_notify (server, &handle_client_disconnect, NULL);
1460 * Shutdown client subsystem.
1465 GNUNET_assert (client_head == NULL);
1466 GNUNET_assert (client_tail == NULL);
1467 if (GNUNET_SCHEDULER_NO_TASK != retry_task)
1469 GNUNET_SCHEDULER_cancel (retry_task);
1470 retry_task = GNUNET_SCHEDULER_NO_TASK;
1472 if (NULL != retry_heap)
1474 GNUNET_assert (0 == GNUNET_CONTAINER_heap_get_size (retry_heap));
1475 GNUNET_CONTAINER_heap_destroy (retry_heap);
1478 if (NULL != forward_map)
1480 GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (forward_map));
1481 GNUNET_CONTAINER_multihashmap_destroy (forward_map);
1486 /* end of gnunet-service-dht_clients.c */