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
7 by the Free Software Foundation; either version 3, or (at your
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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,
18 Boston, MA 02111-1307, USA.
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 DHT routing table 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 GNUNET_SCHEDULER_TaskIdentifier 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_malloc (sizeof (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, struct GNUNET_SERVER_Client *client)
364 struct ClientList *pos;
365 struct PendingMessage *reply;
366 struct ClientMonitorRecord *monitor;
368 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Local client %p disconnects\n", client);
369 pos = find_active_client (client);
370 GNUNET_CONTAINER_DLL_remove (client_head, client_tail, pos);
371 if (pos->transmit_handle != NULL)
372 GNUNET_SERVER_notify_transmit_ready_cancel (pos->transmit_handle);
373 while (NULL != (reply = pos->pending_head))
375 GNUNET_CONTAINER_DLL_remove (pos->pending_head, pos->pending_tail, reply);
378 monitor = monitor_head;
379 while (NULL != monitor)
381 if (monitor->client == pos)
383 struct ClientMonitorRecord *next;
385 GNUNET_free_non_null (monitor->key);
386 next = monitor->next;
387 GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, monitor);
388 GNUNET_free (monitor);
392 monitor = monitor->next;
394 GNUNET_CONTAINER_multihashmap_iterate (forward_map, &remove_client_records,
401 * Route the given request via the DHT. This includes updating
402 * the bloom filter and retransmission times, building the P2P
403 * message and initiating the routing operation.
406 transmit_request (struct ClientQueryRecord *cqr)
408 int32_t reply_bf_mutator;
409 struct GNUNET_CONTAINER_BloomFilter *reply_bf;
410 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
412 GNUNET_STATISTICS_update (GDS_stats,
414 ("# GET requests from clients injected"), 1,
417 (int32_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
420 GNUNET_BLOCK_construct_bloomfilter (reply_bf_mutator, cqr->seen_replies,
421 cqr->seen_replies_count);
423 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
424 GNUNET_CONSTANTS_BLOOMFILTER_K);
425 LOG (GNUNET_ERROR_TYPE_DEBUG,
426 "Initiating GET for %s, replication %u, already have %u replies\n",
427 GNUNET_h2s(&cqr->key), cqr->replication, cqr->seen_replies_count);
428 GDS_NEIGHBOURS_handle_get (cqr->type, cqr->msg_options, cqr->replication,
430 &cqr->key, cqr->xquery, cqr->xquery_size, reply_bf,
431 reply_bf_mutator, peer_bf);
432 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
433 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
435 /* exponential back-off for retries.
436 * max GNUNET_TIME_STD_EXPONENTIAL_BACKOFF_THRESHOLD (15 min) */
437 cqr->retry_frequency = GNUNET_TIME_STD_BACKOFF (cqr->retry_frequency);
438 cqr->retry_time = GNUNET_TIME_relative_to_absolute (cqr->retry_frequency);
443 * Task that looks at the 'retry_heap' and transmits all of the requests
444 * on the heap that are ready for transmission. Then re-schedules
445 * itself (unless the heap is empty).
448 * @param tc scheduler context
451 transmit_next_request_task (void *cls,
452 const struct GNUNET_SCHEDULER_TaskContext *tc)
454 struct ClientQueryRecord *cqr;
455 struct GNUNET_TIME_Relative delay;
457 retry_task = GNUNET_SCHEDULER_NO_TASK;
458 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
460 while (NULL != (cqr = GNUNET_CONTAINER_heap_remove_root (retry_heap)))
463 delay = GNUNET_TIME_absolute_get_remaining (cqr->retry_time);
464 if (delay.rel_value > 0)
467 GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
468 cqr->retry_time.abs_value);
470 GNUNET_SCHEDULER_add_delayed (delay, &transmit_next_request_task,
474 transmit_request (cqr);
476 GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
477 cqr->retry_time.abs_value);
483 * Handler for PUT messages.
485 * @param cls closure for the service
486 * @param client the client we received this message from
487 * @param message the actual message received
490 handle_dht_local_put (void *cls, struct GNUNET_SERVER_Client *client,
491 const struct GNUNET_MessageHeader *message)
493 const struct GNUNET_DHT_ClientPutMessage *dht_msg;
494 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
496 struct PendingMessage *pm;
497 struct GNUNET_DHT_ClientPutConfirmationMessage *conf;
499 size = ntohs (message->size);
500 if (size < sizeof (struct GNUNET_DHT_ClientPutMessage))
503 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
506 GNUNET_STATISTICS_update (GDS_stats,
508 ("# PUT requests received from clients"), 1,
510 dht_msg = (const struct GNUNET_DHT_ClientPutMessage *) message;
511 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "XDHT CLIENT-PUT %s @ %u\n",
512 GNUNET_h2s (&dht_msg->key), getpid ());
513 /* give to local clients */
514 LOG (GNUNET_ERROR_TYPE_DEBUG,
515 "Handling local PUT of %u-bytes for query %s\n",
516 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
517 GNUNET_h2s (&dht_msg->key));
518 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
519 &dht_msg->key, 0, NULL, 0, NULL,
520 ntohl (dht_msg->type),
521 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
524 GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
525 &dht_msg->key, 0, NULL, ntohl (dht_msg->type),
526 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
528 /* route to other peers */
530 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
531 GNUNET_CONSTANTS_BLOOMFILTER_K);
532 GDS_NEIGHBOURS_handle_put (ntohl (dht_msg->type), ntohl (dht_msg->options),
533 ntohl (dht_msg->desired_replication_level),
534 GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
536 peer_bf, &dht_msg->key, 0, NULL, &dht_msg[1],
538 sizeof (struct GNUNET_DHT_ClientPutMessage));
539 GDS_CLIENTS_process_put (ntohl (dht_msg->options),
540 ntohl (dht_msg->type),
542 ntohl (dht_msg->desired_replication_level),
544 GDS_NEIGHBOURS_get_id(),
545 GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
548 size - sizeof (struct GNUNET_DHT_ClientPutMessage));
549 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
550 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
551 sizeof (struct GNUNET_DHT_ClientPutConfirmationMessage));
552 conf = (struct GNUNET_DHT_ClientPutConfirmationMessage *) &pm[1];
553 conf->header.size = htons (sizeof (struct GNUNET_DHT_ClientPutConfirmationMessage));
554 conf->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_CLIENT_PUT_OK);
555 conf->reserved = htonl (0);
556 conf->unique_id = dht_msg->unique_id;
557 pm->msg = &conf->header;
558 add_pending_message (find_active_client (client), pm);
559 GNUNET_SERVER_receive_done (client, GNUNET_OK);
564 * Handler for DHT GET messages from the client.
566 * @param cls closure for the service
567 * @param client the client we received this message from
568 * @param message the actual message received
571 handle_dht_local_get (void *cls, struct GNUNET_SERVER_Client *client,
572 const struct GNUNET_MessageHeader *message)
574 const struct GNUNET_DHT_ClientGetMessage *get;
575 struct ClientQueryRecord *cqr;
580 size = ntohs (message->size);
581 if (size < sizeof (struct GNUNET_DHT_ClientGetMessage))
584 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
587 xquery_size = size - sizeof (struct GNUNET_DHT_ClientGetMessage);
588 get = (const struct GNUNET_DHT_ClientGetMessage *) message;
589 xquery = (const char *) &get[1];
590 GNUNET_STATISTICS_update (GDS_stats,
592 ("# GET requests received from clients"), 1,
594 LOG (GNUNET_ERROR_TYPE_DEBUG,
595 "Received GET request for %s from local client %p, xq: %.*s\n",
596 GNUNET_h2s (&get->key), client, xquery_size, xquery);
598 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "XDHT CLIENT-GET %s @ %u\n",
599 GNUNET_h2s (&get->key), getpid ());
602 cqr = GNUNET_malloc (sizeof (struct ClientQueryRecord) + xquery_size);
604 cqr->client = find_active_client (client);
605 cqr->xquery = (void *) &cqr[1];
606 memcpy (&cqr[1], xquery, xquery_size);
607 cqr->hnode = GNUNET_CONTAINER_heap_insert (retry_heap, cqr, 0);
608 cqr->retry_frequency = GNUNET_TIME_UNIT_SECONDS;
609 cqr->retry_time = GNUNET_TIME_absolute_get ();
610 cqr->unique_id = get->unique_id;
611 cqr->xquery_size = xquery_size;
612 cqr->replication = ntohl (get->desired_replication_level);
613 cqr->msg_options = ntohl (get->options);
614 cqr->type = ntohl (get->type);
615 // FIXME use cqr->key, set multihashmap create to GNUNET_YES
616 GNUNET_CONTAINER_multihashmap_put (forward_map, &get->key, cqr,
617 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
618 GDS_CLIENTS_process_get (ntohl (get->options),
621 ntohl (get->desired_replication_level),
623 GDS_NEIGHBOURS_get_id(),
625 /* start remote requests */
626 if (GNUNET_SCHEDULER_NO_TASK != retry_task)
627 GNUNET_SCHEDULER_cancel (retry_task);
628 retry_task = GNUNET_SCHEDULER_add_now (&transmit_next_request_task, NULL);
629 /* perform local lookup */
630 GDS_DATACACHE_handle_get (&get->key, cqr->type, cqr->xquery, xquery_size,
632 GNUNET_SERVER_receive_done (client, GNUNET_OK);
637 * Closure for 'find_by_unique_id'.
639 struct FindByUniqueIdContext
642 * Where to store the result, if found.
644 struct ClientQueryRecord *cqr;
651 * Function called for each existing DHT record for the given
652 * query. Checks if it matches the UID given in the closure
653 * and if so returns the entry as a result.
655 * @param cls the search context
656 * @param key query for the lookup (not used)
657 * @param value the 'struct ClientQueryRecord'
658 * @return GNUNET_YES to continue iteration (result not yet found)
661 find_by_unique_id (void *cls,
662 const struct GNUNET_HashCode *key,
665 struct FindByUniqueIdContext *fui_ctx = cls;
666 struct ClientQueryRecord *cqr = value;
668 if (cqr->unique_id != fui_ctx->unique_id)
676 * Handler for "GET result seen" messages from the client.
678 * @param cls closure for the service
679 * @param client the client we received this message from
680 * @param message the actual message received
683 handle_dht_local_get_result_seen (void *cls, struct GNUNET_SERVER_Client *client,
684 const struct GNUNET_MessageHeader *message)
686 const struct GNUNET_DHT_ClientGetResultSeenMessage *seen;
688 unsigned int hash_count;
689 unsigned int old_count;
690 const struct GNUNET_HashCode *hc;
691 struct FindByUniqueIdContext fui_ctx;
692 struct ClientQueryRecord *cqr;
694 size = ntohs (message->size);
695 if (size < sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage))
698 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
701 seen = (const struct GNUNET_DHT_ClientGetResultSeenMessage *) message;
702 hash_count = (size - sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage)) / sizeof (struct GNUNET_HashCode);
703 if (size != sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage) + hash_count * sizeof (struct GNUNET_HashCode))
706 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
709 hc = (const struct GNUNET_HashCode*) &seen[1];
710 fui_ctx.unique_id = seen->unique_id;
712 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map,
716 if (NULL == (cqr = fui_ctx.cqr))
719 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
722 /* finally, update 'seen' list */
723 old_count = cqr->seen_replies_count;
724 GNUNET_array_grow (cqr->seen_replies,
725 cqr->seen_replies_count,
726 cqr->seen_replies_count + hash_count);
727 memcpy (&cqr->seen_replies[old_count],
729 sizeof (struct GNUNET_HashCode) * hash_count);
734 * Closure for 'remove_by_unique_id'.
736 struct RemoveByUniqueIdContext
739 * Client that issued the removal request.
741 struct ClientList *client;
744 * Unique ID of the request.
751 * Iterator over hash map entries that frees all entries
752 * that match the given client and unique ID.
754 * @param cls unique ID and client to search for in source routes
755 * @param key current key code
756 * @param value value in the hash map, a ClientQueryRecord
757 * @return GNUNET_YES (we should continue to iterate)
760 remove_by_unique_id (void *cls, const struct GNUNET_HashCode * key, void *value)
762 const struct RemoveByUniqueIdContext *ctx = cls;
763 struct ClientQueryRecord *record = value;
765 if (record->unique_id != ctx->unique_id)
767 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
768 "Removing client %p's record for key %s (by unique id)\n",
769 ctx->client->client_handle, GNUNET_h2s (key));
770 return remove_client_records (ctx->client, key, record);
775 * Handler for any generic DHT stop messages, calls the appropriate handler
776 * depending on message type (if processed locally)
778 * @param cls closure for the service
779 * @param client the client we received this message from
780 * @param message the actual message received
784 handle_dht_local_get_stop (void *cls, struct GNUNET_SERVER_Client *client,
785 const struct GNUNET_MessageHeader *message)
787 const struct GNUNET_DHT_ClientGetStopMessage *dht_stop_msg =
788 (const struct GNUNET_DHT_ClientGetStopMessage *) message;
789 struct RemoveByUniqueIdContext ctx;
791 GNUNET_STATISTICS_update (GDS_stats,
793 ("# GET STOP requests received from clients"), 1,
795 LOG (GNUNET_ERROR_TYPE_DEBUG,
796 "Received GET STOP request for %s from local client %p\n",
797 client, GNUNET_h2s (&dht_stop_msg->key));
798 ctx.client = find_active_client (client);
799 ctx.unique_id = dht_stop_msg->unique_id;
800 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, &dht_stop_msg->key,
801 &remove_by_unique_id, &ctx);
802 GNUNET_SERVER_receive_done (client, GNUNET_OK);
807 * Handler for monitor start messages
809 * @param cls closure for the service
810 * @param client the client we received this message from
811 * @param message the actual message received
815 handle_dht_local_monitor (void *cls, struct GNUNET_SERVER_Client *client,
816 const struct GNUNET_MessageHeader *message)
818 struct ClientMonitorRecord *r;
819 const struct GNUNET_DHT_MonitorStartStopMessage *msg;
821 msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
822 r = GNUNET_malloc (sizeof(struct ClientMonitorRecord));
824 r->client = find_active_client(client);
825 r->type = ntohl(msg->type);
826 r->get = ntohs(msg->get);
827 r->get_resp = ntohs(msg->get_resp);
828 r->put = ntohs(msg->put);
829 if (0 == ntohs(msg->filter_key))
833 r->key = GNUNET_malloc (sizeof (struct GNUNET_HashCode));
834 memcpy (r->key, &msg->key, sizeof (struct GNUNET_HashCode));
836 GNUNET_CONTAINER_DLL_insert (monitor_head, monitor_tail, r);
837 GNUNET_SERVER_receive_done (client, GNUNET_OK);
841 * Handler for monitor stop messages
843 * @param cls closure for the service
844 * @param client the client we received this message from
845 * @param message the actual message received
849 handle_dht_local_monitor_stop (void *cls, struct GNUNET_SERVER_Client *client,
850 const struct GNUNET_MessageHeader *message)
852 struct ClientMonitorRecord *r;
853 const struct GNUNET_DHT_MonitorStartStopMessage *msg;
856 msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
862 keys_match = (0 == ntohs(msg->filter_key));
865 keys_match = (0 != ntohs(msg->filter_key)
866 && !memcmp(r->key, &msg->key, sizeof(struct GNUNET_HashCode)));
868 if (find_active_client(client) == r->client
869 && ntohl(msg->type) == r->type
870 && r->get == msg->get
871 && r->get_resp == msg->get_resp
872 && r->put == msg->put
876 GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, r);
877 GNUNET_free_non_null (r->key);
879 GNUNET_SERVER_receive_done (client, GNUNET_OK);
880 return; /* Delete only ONE entry */
885 GNUNET_SERVER_receive_done (client, GNUNET_OK);
890 * Callback called as a result of issuing a GNUNET_SERVER_notify_transmit_ready
891 * request. A ClientList is passed as closure, take the head of the list
892 * and copy it into buf, which has the result of sending the message to the
895 * @param cls closure to this call
896 * @param size maximum number of bytes available to send
897 * @param buf where to copy the actual message to
899 * @return the number of bytes actually copied, 0 indicates failure
902 send_reply_to_client (void *cls, size_t size, void *buf)
904 struct ClientList *client = cls;
906 struct PendingMessage *reply;
910 client->transmit_handle = NULL;
913 /* client disconnected */
914 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
915 "Client %p disconnected, pending messages will be discarded\n",
916 client->client_handle);
920 while ((NULL != (reply = client->pending_head)) &&
921 (size >= off + (msize = ntohs (reply->msg->size))))
923 GNUNET_CONTAINER_DLL_remove (client->pending_head, client->pending_tail,
925 memcpy (&cbuf[off], reply->msg, msize);
927 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u bytes to client %p\n",
928 msize, client->client_handle);
931 process_pending_messages (client);
932 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitted %u/%u bytes to client %p\n",
933 (unsigned int) off, (unsigned int) size, client->client_handle);
939 * Task run to check for messages that need to be sent to a client.
941 * @param client a ClientList, containing the client and any messages to be sent to it
944 process_pending_messages (struct ClientList *client)
946 if ((client->pending_head == NULL) || (client->transmit_handle != NULL))
948 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
949 "Not asking for transmission to %p now: %s\n",
950 client->client_handle,
951 client->pending_head ==
952 NULL ? "no more messages" : "request already pending");
955 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
956 "Asking for transmission of %u bytes to client %p\n",
957 ntohs (client->pending_head->msg->size), client->client_handle);
958 client->transmit_handle =
959 GNUNET_SERVER_notify_transmit_ready (client->client_handle,
960 ntohs (client->pending_head->
962 GNUNET_TIME_UNIT_FOREVER_REL,
963 &send_reply_to_client, client);
968 * Closure for 'forward_reply'
970 struct ForwardReplyContext
974 * Actual message to send to matching clients.
976 struct PendingMessage *pm;
986 enum GNUNET_BLOCK_Type type;
989 * Number of bytes in data.
994 * Do we need to copy 'pm' because it was already used?
1002 * Iterator over hash map entries that send a given reply to
1003 * each of the matching clients. With some tricky recycling
1006 * @param cls the 'struct ForwardReplyContext'
1007 * @param key current key
1008 * @param value value in the hash map, a ClientQueryRecord
1009 * @return GNUNET_YES (we should continue to iterate),
1010 * if the result is mal-formed, GNUNET_NO
1013 forward_reply (void *cls, const struct GNUNET_HashCode * key, void *value)
1015 struct ForwardReplyContext *frc = cls;
1016 struct ClientQueryRecord *record = value;
1017 struct PendingMessage *pm;
1018 struct GNUNET_DHT_ClientResultMessage *reply;
1019 enum GNUNET_BLOCK_EvaluationResult eval;
1021 struct GNUNET_HashCode ch;
1024 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "XDHT CLIENT-RESULT %s @ %u\n",
1025 GNUNET_h2s (key), getpid ());
1026 if ((record->type != GNUNET_BLOCK_TYPE_ANY) && (record->type != frc->type))
1028 LOG (GNUNET_ERROR_TYPE_DEBUG,
1029 "Record type missmatch, not passing request for key %s to local client\n",
1031 GNUNET_STATISTICS_update (GDS_stats,
1033 ("# Key match, type mismatches in REPLY to CLIENT"),
1035 return GNUNET_YES; /* type mismatch */
1037 GNUNET_CRYPTO_hash (frc->data, frc->data_size, &ch);
1038 for (i = 0; i < record->seen_replies_count; i++)
1039 if (0 == memcmp (&record->seen_replies[i], &ch, sizeof (struct GNUNET_HashCode)))
1041 LOG (GNUNET_ERROR_TYPE_DEBUG,
1042 "Duplicate reply, not passing request for key %s to local client\n",
1044 GNUNET_STATISTICS_update (GDS_stats,
1046 ("# Duplicate REPLIES to CLIENT request dropped"),
1048 return GNUNET_YES; /* duplicate */
1051 GNUNET_BLOCK_evaluate (GDS_block_context, record->type, key, NULL, 0,
1052 record->xquery, record->xquery_size, frc->data,
1054 LOG (GNUNET_ERROR_TYPE_DEBUG,
1055 "Evaluation result is %d for key %s for local client's query\n",
1056 (int) eval, GNUNET_h2s (key));
1059 case GNUNET_BLOCK_EVALUATION_OK_LAST:
1060 do_free = GNUNET_YES;
1062 case GNUNET_BLOCK_EVALUATION_OK_MORE:
1063 GNUNET_array_append (record->seen_replies, record->seen_replies_count, ch);
1064 do_free = GNUNET_NO;
1066 case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
1067 /* should be impossible to encounter here */
1070 case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
1071 GNUNET_break_op (0);
1073 case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
1076 case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
1079 case GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT:
1081 case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
1082 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1083 _("Unsupported block type (%u) in request!\n"), record->type);
1089 if (GNUNET_NO == frc->do_copy)
1091 /* first time, we can use the original data */
1093 frc->do_copy = GNUNET_YES;
1097 /* two clients waiting for same reply, must copy for queueing */
1098 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
1099 ntohs (frc->pm->msg->size));
1100 memcpy (pm, frc->pm,
1101 sizeof (struct PendingMessage) + ntohs (frc->pm->msg->size));
1102 pm->next = pm->prev = NULL;
1103 pm->msg = (struct GNUNET_MessageHeader *) &pm[1];
1105 GNUNET_STATISTICS_update (GDS_stats,
1106 gettext_noop ("# RESULTS queued for clients"), 1,
1108 reply = (struct GNUNET_DHT_ClientResultMessage *) &pm[1];
1109 reply->unique_id = record->unique_id;
1110 LOG (GNUNET_ERROR_TYPE_DEBUG,
1111 "Queueing reply to query %s for client %p\n", GNUNET_h2s (key),
1112 record->client->client_handle);
1113 add_pending_message (record->client, pm);
1114 if (GNUNET_YES == do_free)
1115 remove_client_records (record->client, key, record);
1121 * Handle a reply we've received from another peer. If the reply
1122 * matches any of our pending queries, forward it to the respective
1125 * @param expiration when will the reply expire
1126 * @param key the query this reply is for
1127 * @param get_path_length number of peers in 'get_path'
1128 * @param get_path path the reply took on get
1129 * @param put_path_length number of peers in 'put_path'
1130 * @param put_path path the reply took on put
1131 * @param type type of the reply
1132 * @param data_size number of bytes in 'data'
1133 * @param data application payload data
1136 GDS_CLIENTS_handle_reply (struct GNUNET_TIME_Absolute expiration,
1137 const struct GNUNET_HashCode *key,
1138 unsigned int get_path_length,
1139 const struct GNUNET_PeerIdentity *get_path,
1140 unsigned int put_path_length,
1141 const struct GNUNET_PeerIdentity *put_path,
1142 enum GNUNET_BLOCK_Type type, size_t data_size,
1145 struct ForwardReplyContext frc;
1146 struct PendingMessage *pm;
1147 struct GNUNET_DHT_ClientResultMessage *reply;
1148 struct GNUNET_PeerIdentity *paths;
1151 LOG (GNUNET_ERROR_TYPE_DEBUG, "reply for key %s\n", GNUNET_h2s (key));
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 */