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 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 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_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).
453 * @param tc scheduler context
456 transmit_next_request_task (void *cls,
457 const struct GNUNET_SCHEDULER_TaskContext *tc)
459 struct ClientQueryRecord *cqr;
460 struct GNUNET_TIME_Relative delay;
462 retry_task = GNUNET_SCHEDULER_NO_TASK;
463 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
465 while (NULL != (cqr = GNUNET_CONTAINER_heap_remove_root (retry_heap)))
468 delay = GNUNET_TIME_absolute_get_remaining (cqr->retry_time);
469 if (delay.rel_value_us > 0)
472 GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
473 cqr->retry_time.abs_value_us);
475 GNUNET_SCHEDULER_add_delayed (delay, &transmit_next_request_task,
479 transmit_request (cqr);
481 GNUNET_CONTAINER_heap_insert (retry_heap, cqr,
482 cqr->retry_time.abs_value_us);
488 * Handler for PUT messages.
490 * @param cls closure for the service
491 * @param client the client we received this message from
492 * @param message the actual message received
495 handle_dht_local_put (void *cls, struct GNUNET_SERVER_Client *client,
496 const struct GNUNET_MessageHeader *message)
498 const struct GNUNET_DHT_ClientPutMessage *dht_msg;
499 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
501 struct PendingMessage *pm;
502 struct GNUNET_DHT_ClientPutConfirmationMessage *conf;
504 size = ntohs (message->size);
505 if (size < sizeof (struct GNUNET_DHT_ClientPutMessage))
508 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
511 GNUNET_STATISTICS_update (GDS_stats,
513 ("# PUT requests received from clients"), 1,
515 dht_msg = (const struct GNUNET_DHT_ClientPutMessage *) message;
516 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "R5N CLIENT-PUT %s\n",
517 GNUNET_h2s_full (&dht_msg->key));
518 /* give to local clients */
519 LOG (GNUNET_ERROR_TYPE_DEBUG,
520 "Handling local PUT of %u-bytes for query %s\n",
521 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
522 GNUNET_h2s (&dht_msg->key));
523 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
524 &dht_msg->key, 0, NULL, 0, NULL,
525 ntohl (dht_msg->type),
526 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
529 GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
530 &dht_msg->key, 0, NULL, ntohl (dht_msg->type),
531 size - sizeof (struct GNUNET_DHT_ClientPutMessage),
533 /* route to other peers */
535 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
536 GNUNET_CONSTANTS_BLOOMFILTER_K);
537 GDS_NEIGHBOURS_handle_put (ntohl (dht_msg->type), ntohl (dht_msg->options),
538 ntohl (dht_msg->desired_replication_level),
539 GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
541 peer_bf, &dht_msg->key, 0, NULL, &dht_msg[1],
543 sizeof (struct GNUNET_DHT_ClientPutMessage));
544 GDS_CLIENTS_process_put (ntohl (dht_msg->options),
545 ntohl (dht_msg->type),
547 ntohl (dht_msg->desired_replication_level),
549 GDS_NEIGHBOURS_get_id(),
550 GNUNET_TIME_absolute_ntoh (dht_msg->expiration),
553 size - sizeof (struct GNUNET_DHT_ClientPutMessage));
554 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
555 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
556 sizeof (struct GNUNET_DHT_ClientPutConfirmationMessage));
557 conf = (struct GNUNET_DHT_ClientPutConfirmationMessage *) &pm[1];
558 conf->header.size = htons (sizeof (struct GNUNET_DHT_ClientPutConfirmationMessage));
559 conf->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_CLIENT_PUT_OK);
560 conf->reserved = htonl (0);
561 conf->unique_id = dht_msg->unique_id;
562 pm->msg = &conf->header;
563 add_pending_message (find_active_client (client), pm);
564 GNUNET_SERVER_receive_done (client, GNUNET_OK);
569 * Handler for DHT GET messages from the client.
571 * @param cls closure for the service
572 * @param client the client we received this message from
573 * @param message the actual message received
576 handle_dht_local_get (void *cls, struct GNUNET_SERVER_Client *client,
577 const struct GNUNET_MessageHeader *message)
579 const struct GNUNET_DHT_ClientGetMessage *get;
580 struct ClientQueryRecord *cqr;
585 size = ntohs (message->size);
586 if (size < sizeof (struct GNUNET_DHT_ClientGetMessage))
589 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
592 xquery_size = size - sizeof (struct GNUNET_DHT_ClientGetMessage);
593 get = (const struct GNUNET_DHT_ClientGetMessage *) message;
594 xquery = (const char *) &get[1];
595 GNUNET_STATISTICS_update (GDS_stats,
597 ("# GET requests received from clients"), 1,
599 LOG (GNUNET_ERROR_TYPE_DEBUG,
600 "Received GET request for %s from local client %p, xq: %.*s\n",
601 GNUNET_h2s (&get->key), client, xquery_size, xquery);
603 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "R5N CLIENT-GET %s\n",
604 GNUNET_h2s_full (&get->key));
607 cqr = GNUNET_malloc (sizeof (struct ClientQueryRecord) + xquery_size);
609 cqr->client = find_active_client (client);
610 cqr->xquery = (void *) &cqr[1];
611 memcpy (&cqr[1], xquery, xquery_size);
612 cqr->hnode = GNUNET_CONTAINER_heap_insert (retry_heap, cqr, 0);
613 cqr->retry_frequency = GNUNET_TIME_UNIT_SECONDS;
614 cqr->retry_time = GNUNET_TIME_absolute_get ();
615 cqr->unique_id = get->unique_id;
616 cqr->xquery_size = xquery_size;
617 cqr->replication = ntohl (get->desired_replication_level);
618 cqr->msg_options = ntohl (get->options);
619 cqr->type = ntohl (get->type);
620 // FIXME use cqr->key, set multihashmap create to GNUNET_YES
621 GNUNET_CONTAINER_multihashmap_put (forward_map, &get->key, cqr,
622 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
623 GDS_CLIENTS_process_get (ntohl (get->options),
626 ntohl (get->desired_replication_level),
628 GDS_NEIGHBOURS_get_id(),
630 /* start remote requests */
631 if (GNUNET_SCHEDULER_NO_TASK != retry_task)
632 GNUNET_SCHEDULER_cancel (retry_task);
633 retry_task = GNUNET_SCHEDULER_add_now (&transmit_next_request_task, NULL);
634 /* perform local lookup */
635 GDS_DATACACHE_handle_get (&get->key, cqr->type, cqr->xquery, xquery_size,
637 GNUNET_SERVER_receive_done (client, GNUNET_OK);
642 * Closure for 'find_by_unique_id'.
644 struct FindByUniqueIdContext
647 * Where to store the result, if found.
649 struct ClientQueryRecord *cqr;
656 * Function called for each existing DHT record for the given
657 * query. Checks if it matches the UID given in the closure
658 * and if so returns the entry as a result.
660 * @param cls the search context
661 * @param key query for the lookup (not used)
662 * @param value the 'struct ClientQueryRecord'
663 * @return GNUNET_YES to continue iteration (result not yet found)
666 find_by_unique_id (void *cls,
667 const struct GNUNET_HashCode *key,
670 struct FindByUniqueIdContext *fui_ctx = cls;
671 struct ClientQueryRecord *cqr = value;
673 if (cqr->unique_id != fui_ctx->unique_id)
681 * Handler for "GET result seen" messages from the client.
683 * @param cls closure for the service
684 * @param client the client we received this message from
685 * @param message the actual message received
688 handle_dht_local_get_result_seen (void *cls, struct GNUNET_SERVER_Client *client,
689 const struct GNUNET_MessageHeader *message)
691 const struct GNUNET_DHT_ClientGetResultSeenMessage *seen;
693 unsigned int hash_count;
694 unsigned int old_count;
695 const struct GNUNET_HashCode *hc;
696 struct FindByUniqueIdContext fui_ctx;
697 struct ClientQueryRecord *cqr;
699 size = ntohs (message->size);
700 if (size < sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage))
703 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
706 seen = (const struct GNUNET_DHT_ClientGetResultSeenMessage *) message;
707 hash_count = (size - sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage)) / sizeof (struct GNUNET_HashCode);
708 if (size != sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage) + hash_count * sizeof (struct GNUNET_HashCode))
711 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
714 hc = (const struct GNUNET_HashCode*) &seen[1];
715 fui_ctx.unique_id = seen->unique_id;
717 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map,
721 if (NULL == (cqr = fui_ctx.cqr))
724 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
727 /* finally, update 'seen' list */
728 old_count = cqr->seen_replies_count;
729 GNUNET_array_grow (cqr->seen_replies,
730 cqr->seen_replies_count,
731 cqr->seen_replies_count + hash_count);
732 memcpy (&cqr->seen_replies[old_count],
734 sizeof (struct GNUNET_HashCode) * hash_count);
739 * Closure for 'remove_by_unique_id'.
741 struct RemoveByUniqueIdContext
744 * Client that issued the removal request.
746 struct ClientList *client;
749 * Unique ID of the request.
756 * Iterator over hash map entries that frees all entries
757 * that match the given client and unique ID.
759 * @param cls unique ID and client to search for in source routes
760 * @param key current key code
761 * @param value value in the hash map, a ClientQueryRecord
762 * @return GNUNET_YES (we should continue to iterate)
765 remove_by_unique_id (void *cls, const struct GNUNET_HashCode * key, void *value)
767 const struct RemoveByUniqueIdContext *ctx = cls;
768 struct ClientQueryRecord *record = value;
770 if (record->unique_id != ctx->unique_id)
772 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
773 "Removing client %p's record for key %s (by unique id)\n",
774 ctx->client->client_handle, GNUNET_h2s (key));
775 return remove_client_records (ctx->client, key, record);
780 * Handler for any generic DHT stop messages, calls the appropriate handler
781 * depending on message type (if processed locally)
783 * @param cls closure for the service
784 * @param client the client we received this message from
785 * @param message the actual message received
789 handle_dht_local_get_stop (void *cls, struct GNUNET_SERVER_Client *client,
790 const struct GNUNET_MessageHeader *message)
792 const struct GNUNET_DHT_ClientGetStopMessage *dht_stop_msg =
793 (const struct GNUNET_DHT_ClientGetStopMessage *) message;
794 struct RemoveByUniqueIdContext ctx;
796 GNUNET_STATISTICS_update (GDS_stats,
798 ("# GET STOP requests received from clients"), 1,
800 LOG (GNUNET_ERROR_TYPE_DEBUG,
801 "Received GET STOP request for %s from local client %p\n",
802 client, GNUNET_h2s (&dht_stop_msg->key));
803 ctx.client = find_active_client (client);
804 ctx.unique_id = dht_stop_msg->unique_id;
805 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, &dht_stop_msg->key,
806 &remove_by_unique_id, &ctx);
807 GNUNET_SERVER_receive_done (client, GNUNET_OK);
812 * Handler for monitor start messages
814 * @param cls closure for the service
815 * @param client the client we received this message from
816 * @param message the actual message received
820 handle_dht_local_monitor (void *cls, struct GNUNET_SERVER_Client *client,
821 const struct GNUNET_MessageHeader *message)
823 struct ClientMonitorRecord *r;
824 const struct GNUNET_DHT_MonitorStartStopMessage *msg;
826 msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
827 r = GNUNET_new (struct ClientMonitorRecord);
829 r->client = find_active_client(client);
830 r->type = ntohl(msg->type);
831 r->get = ntohs(msg->get);
832 r->get_resp = ntohs(msg->get_resp);
833 r->put = ntohs(msg->put);
834 if (0 == ntohs(msg->filter_key))
838 r->key = GNUNET_new (struct GNUNET_HashCode);
839 memcpy (r->key, &msg->key, sizeof (struct GNUNET_HashCode));
841 GNUNET_CONTAINER_DLL_insert (monitor_head, monitor_tail, r);
842 GNUNET_SERVER_receive_done (client, GNUNET_OK);
846 * Handler for monitor stop messages
848 * @param cls closure for the service
849 * @param client the client we received this message from
850 * @param message the actual message received
854 handle_dht_local_monitor_stop (void *cls, struct GNUNET_SERVER_Client *client,
855 const struct GNUNET_MessageHeader *message)
857 struct ClientMonitorRecord *r;
858 const struct GNUNET_DHT_MonitorStartStopMessage *msg;
861 msg = (struct GNUNET_DHT_MonitorStartStopMessage *) message;
867 keys_match = (0 == ntohs(msg->filter_key));
870 keys_match = (0 != ntohs(msg->filter_key)
871 && !memcmp(r->key, &msg->key, sizeof(struct GNUNET_HashCode)));
873 if (find_active_client(client) == r->client
874 && ntohl(msg->type) == r->type
875 && r->get == msg->get
876 && r->get_resp == msg->get_resp
877 && r->put == msg->put
881 GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, r);
882 GNUNET_free_non_null (r->key);
884 GNUNET_SERVER_receive_done (client, GNUNET_OK);
885 return; /* Delete only ONE entry */
890 GNUNET_SERVER_receive_done (client, GNUNET_OK);
895 * Callback called as a result of issuing a GNUNET_SERVER_notify_transmit_ready
896 * request. A ClientList is passed as closure, take the head of the list
897 * and copy it into buf, which has the result of sending the message to the
900 * @param cls closure to this call
901 * @param size maximum number of bytes available to send
902 * @param buf where to copy the actual message to
904 * @return the number of bytes actually copied, 0 indicates failure
907 send_reply_to_client (void *cls, size_t size, void *buf)
909 struct ClientList *client = cls;
911 struct PendingMessage *reply;
915 client->transmit_handle = NULL;
918 /* client disconnected */
919 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
920 "Client %p disconnected, pending messages will be discarded\n",
921 client->client_handle);
925 while ((NULL != (reply = client->pending_head)) &&
926 (size >= off + (msize = ntohs (reply->msg->size))))
928 GNUNET_CONTAINER_DLL_remove (client->pending_head, client->pending_tail,
930 memcpy (&cbuf[off], reply->msg, msize);
932 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitting %u bytes to client %p\n",
933 msize, client->client_handle);
936 process_pending_messages (client);
937 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitted %u/%u bytes to client %p\n",
938 (unsigned int) off, (unsigned int) size, client->client_handle);
944 * Task run to check for messages that need to be sent to a client.
946 * @param client a ClientList, containing the client and any messages to be sent to it
949 process_pending_messages (struct ClientList *client)
951 if ((client->pending_head == NULL) || (client->transmit_handle != NULL))
953 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
954 "Not asking for transmission to %p now: %s\n",
955 client->client_handle,
956 client->pending_head ==
957 NULL ? "no more messages" : "request already pending");
960 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
961 "Asking for transmission of %u bytes to client %p\n",
962 ntohs (client->pending_head->msg->size), client->client_handle);
963 client->transmit_handle =
964 GNUNET_SERVER_notify_transmit_ready (client->client_handle,
965 ntohs (client->pending_head->
967 GNUNET_TIME_UNIT_FOREVER_REL,
968 &send_reply_to_client, client);
973 * Closure for 'forward_reply'
975 struct ForwardReplyContext
979 * Actual message to send to matching clients.
981 struct PendingMessage *pm;
991 enum GNUNET_BLOCK_Type type;
994 * Number of bytes in data.
999 * Do we need to copy 'pm' because it was already used?
1007 * Iterator over hash map entries that send a given reply to
1008 * each of the matching clients. With some tricky recycling
1011 * @param cls the 'struct ForwardReplyContext'
1012 * @param key current key
1013 * @param value value in the hash map, a ClientQueryRecord
1014 * @return GNUNET_YES (we should continue to iterate),
1015 * if the result is mal-formed, GNUNET_NO
1018 forward_reply (void *cls, const struct GNUNET_HashCode * key, void *value)
1020 struct ForwardReplyContext *frc = cls;
1021 struct ClientQueryRecord *record = value;
1022 struct PendingMessage *pm;
1023 struct GNUNET_DHT_ClientResultMessage *reply;
1024 enum GNUNET_BLOCK_EvaluationResult eval;
1026 struct GNUNET_HashCode ch;
1029 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG,
1030 "R5N CLIENT-RESULT %s\n",
1031 GNUNET_h2s_full (key));
1032 if ((record->type != GNUNET_BLOCK_TYPE_ANY) && (record->type != frc->type))
1034 LOG (GNUNET_ERROR_TYPE_DEBUG,
1035 "Record type missmatch, not passing request for key %s to local client\n",
1037 GNUNET_STATISTICS_update (GDS_stats,
1039 ("# Key match, type mismatches in REPLY to CLIENT"),
1041 return GNUNET_YES; /* type mismatch */
1043 GNUNET_CRYPTO_hash (frc->data, frc->data_size, &ch);
1044 for (i = 0; i < record->seen_replies_count; i++)
1045 if (0 == memcmp (&record->seen_replies[i], &ch, sizeof (struct GNUNET_HashCode)))
1047 LOG (GNUNET_ERROR_TYPE_DEBUG,
1048 "Duplicate reply, not passing request for key %s to local client\n",
1050 GNUNET_STATISTICS_update (GDS_stats,
1052 ("# Duplicate REPLIES to CLIENT request dropped"),
1054 return GNUNET_YES; /* duplicate */
1057 GNUNET_BLOCK_evaluate (GDS_block_context, record->type, key, NULL, 0,
1058 record->xquery, record->xquery_size, frc->data,
1060 LOG (GNUNET_ERROR_TYPE_DEBUG,
1061 "Evaluation result is %d for key %s for local client's query\n",
1062 (int) eval, GNUNET_h2s (key));
1065 case GNUNET_BLOCK_EVALUATION_OK_LAST:
1066 do_free = GNUNET_YES;
1068 case GNUNET_BLOCK_EVALUATION_OK_MORE:
1069 GNUNET_array_append (record->seen_replies, record->seen_replies_count, ch);
1070 do_free = GNUNET_NO;
1072 case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
1073 /* should be impossible to encounter here */
1076 case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
1077 GNUNET_break_op (0);
1079 case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
1082 case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
1085 case GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT:
1087 case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
1088 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1089 _("Unsupported block type (%u) in request!\n"), record->type);
1095 if (GNUNET_NO == frc->do_copy)
1097 /* first time, we can use the original data */
1099 frc->do_copy = GNUNET_YES;
1103 /* two clients waiting for same reply, must copy for queueing */
1104 pm = GNUNET_malloc (sizeof (struct PendingMessage) +
1105 ntohs (frc->pm->msg->size));
1106 memcpy (pm, frc->pm,
1107 sizeof (struct PendingMessage) + ntohs (frc->pm->msg->size));
1108 pm->next = pm->prev = NULL;
1109 pm->msg = (struct GNUNET_MessageHeader *) &pm[1];
1111 GNUNET_STATISTICS_update (GDS_stats,
1112 gettext_noop ("# RESULTS queued for clients"), 1,
1114 reply = (struct GNUNET_DHT_ClientResultMessage *) &pm[1];
1115 reply->unique_id = record->unique_id;
1116 LOG (GNUNET_ERROR_TYPE_DEBUG,
1117 "Queueing reply to query %s for client %p\n",
1119 record->client->client_handle);
1120 add_pending_message (record->client, pm);
1121 if (GNUNET_YES == do_free)
1122 remove_client_records (record->client, key, record);
1128 * Handle a reply we've received from another peer. If the reply
1129 * matches any of our pending queries, forward it to the respective
1132 * @param expiration when will the reply expire
1133 * @param key the query this reply is for
1134 * @param get_path_length number of peers in @a get_path
1135 * @param get_path path the reply took on get
1136 * @param put_path_length number of peers in @a put_path
1137 * @param put_path path the reply took on put
1138 * @param type type of the reply
1139 * @param data_size number of bytes in @a data
1140 * @param data application payload data
1143 GDS_CLIENTS_handle_reply (struct GNUNET_TIME_Absolute expiration,
1144 const struct GNUNET_HashCode *key,
1145 unsigned int get_path_length,
1146 const struct GNUNET_PeerIdentity *get_path,
1147 unsigned int put_path_length,
1148 const struct GNUNET_PeerIdentity *put_path,
1149 enum GNUNET_BLOCK_Type type, size_t data_size,
1152 struct ForwardReplyContext frc;
1153 struct PendingMessage *pm;
1154 struct GNUNET_DHT_ClientResultMessage *reply;
1155 struct GNUNET_PeerIdentity *paths;
1158 LOG (GNUNET_ERROR_TYPE_DEBUG,
1159 "reply for key %s\n",
1162 if (NULL == GNUNET_CONTAINER_multihashmap_get (forward_map, key))
1164 GNUNET_STATISTICS_update (GDS_stats,
1166 ("# REPLIES ignored for CLIENTS (no match)"), 1,
1168 return; /* no matching request, fast exit! */
1171 sizeof (struct GNUNET_DHT_ClientResultMessage) + data_size +
1172 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity);
1173 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1175 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1176 _("Could not pass reply to client, message too big!\n"));
1179 pm = GNUNET_malloc (msize + sizeof (struct PendingMessage));
1180 reply = (struct GNUNET_DHT_ClientResultMessage *) &pm[1];
1181 pm->msg = &reply->header;
1182 reply->header.size = htons ((uint16_t) msize);
1183 reply->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_CLIENT_RESULT);
1184 reply->type = htonl (type);
1185 reply->get_path_length = htonl (get_path_length);
1186 reply->put_path_length = htonl (put_path_length);
1187 reply->unique_id = 0; /* filled in later */
1188 reply->expiration = GNUNET_TIME_absolute_hton (expiration);
1190 paths = (struct GNUNET_PeerIdentity *) &reply[1];
1191 memcpy (paths, put_path,
1192 sizeof (struct GNUNET_PeerIdentity) * put_path_length);
1193 memcpy (&paths[put_path_length], get_path,
1194 sizeof (struct GNUNET_PeerIdentity) * get_path_length);
1195 memcpy (&paths[get_path_length + put_path_length], data, data_size);
1196 frc.do_copy = GNUNET_NO;
1199 frc.data_size = data_size;
1201 GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, key, &forward_reply,
1204 if (GNUNET_NO == frc.do_copy)
1206 /* did not match any of the requests, free! */
1207 GNUNET_STATISTICS_update (GDS_stats,
1209 ("# REPLIES ignored for CLIENTS (no match)"), 1,
1217 * Check if some client is monitoring GET messages and notify
1218 * them in that case.
1220 * @param options Options, for instance RecordRoute, DemultiplexEverywhere.
1221 * @param type The type of data in the request.
1222 * @param hop_count Hop count so far.
1223 * @param path_length number of entries in path (or 0 if not recorded).
1224 * @param path peers on the GET path (or NULL if not recorded).
1225 * @param desired_replication_level Desired replication level.
1226 * @param key Key of the requested data.
1229 GDS_CLIENTS_process_get (uint32_t options,
1230 enum GNUNET_BLOCK_Type type,
1232 uint32_t desired_replication_level,
1233 unsigned int path_length,
1234 const struct GNUNET_PeerIdentity *path,
1235 const struct GNUNET_HashCode * key)
1237 struct ClientMonitorRecord *m;
1238 struct ClientList **cl;
1239 unsigned int cl_size;
1243 for (m = monitor_head; NULL != m; m = m->next)
1245 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1247 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1249 struct PendingMessage *pm;
1250 struct GNUNET_DHT_MonitorGetMessage *mmsg;
1251 struct GNUNET_PeerIdentity *msg_path;
1255 /* Don't send duplicates */
1256 for (i = 0; i < cl_size; i++)
1257 if (cl[i] == m->client)
1261 GNUNET_array_append (cl, cl_size, m->client);
1263 msize = path_length * sizeof (struct GNUNET_PeerIdentity);
1264 msize += sizeof (struct GNUNET_DHT_MonitorGetMessage);
1265 msize += sizeof (struct PendingMessage);
1266 pm = GNUNET_malloc (msize);
1267 mmsg = (struct GNUNET_DHT_MonitorGetMessage *) &pm[1];
1268 pm->msg = &mmsg->header;
1269 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1270 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_GET);
1271 mmsg->options = htonl(options);
1272 mmsg->type = htonl(type);
1273 mmsg->hop_count = htonl(hop_count);
1274 mmsg->desired_replication_level = htonl(desired_replication_level);
1275 mmsg->get_path_length = htonl(path_length);
1276 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1277 msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1278 if (path_length > 0)
1279 memcpy (msg_path, path,
1280 path_length * sizeof (struct GNUNET_PeerIdentity));
1281 add_pending_message (m->client, pm);
1284 GNUNET_free_non_null (cl);
1289 * Check if some client is monitoring GET RESP messages and notify
1290 * them in that case.
1292 * @param type The type of data in the result.
1293 * @param get_path Peers on GET path (or NULL if not recorded).
1294 * @param get_path_length number of entries in get_path.
1295 * @param put_path peers on the PUT path (or NULL if not recorded).
1296 * @param put_path_length number of entries in get_path.
1297 * @param exp Expiration time of the data.
1298 * @param key Key of the data.
1299 * @param data Pointer to the result data.
1300 * @param size Number of bytes in data.
1303 GDS_CLIENTS_process_get_resp (enum GNUNET_BLOCK_Type type,
1304 const struct GNUNET_PeerIdentity *get_path,
1305 unsigned int get_path_length,
1306 const struct GNUNET_PeerIdentity *put_path,
1307 unsigned int put_path_length,
1308 struct GNUNET_TIME_Absolute exp,
1309 const struct GNUNET_HashCode * key,
1313 struct ClientMonitorRecord *m;
1314 struct ClientList **cl;
1315 unsigned int cl_size;
1319 for (m = monitor_head; NULL != m; m = m->next)
1321 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1323 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1325 struct PendingMessage *pm;
1326 struct GNUNET_DHT_MonitorGetRespMessage *mmsg;
1327 struct GNUNET_PeerIdentity *path;
1331 /* Don't send duplicates */
1332 for (i = 0; i < cl_size; i++)
1333 if (cl[i] == m->client)
1337 GNUNET_array_append (cl, cl_size, m->client);
1340 msize += (get_path_length + put_path_length)
1341 * sizeof (struct GNUNET_PeerIdentity);
1342 msize += sizeof (struct GNUNET_DHT_MonitorGetRespMessage);
1343 msize += sizeof (struct PendingMessage);
1344 pm = GNUNET_malloc (msize);
1345 mmsg = (struct GNUNET_DHT_MonitorGetRespMessage *) &pm[1];
1346 pm->msg = (struct GNUNET_MessageHeader *) mmsg;
1347 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1348 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_GET_RESP);
1349 mmsg->type = htonl(type);
1350 mmsg->put_path_length = htonl(put_path_length);
1351 mmsg->get_path_length = htonl(get_path_length);
1352 path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1353 if (put_path_length > 0)
1355 memcpy (path, put_path,
1356 put_path_length * sizeof (struct GNUNET_PeerIdentity));
1357 path = &path[put_path_length];
1359 if (get_path_length > 0)
1360 memcpy (path, get_path,
1361 get_path_length * sizeof (struct GNUNET_PeerIdentity));
1362 mmsg->expiration_time = GNUNET_TIME_absolute_hton(exp);
1363 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1365 memcpy (&path[get_path_length], data, size);
1366 add_pending_message (m->client, pm);
1369 GNUNET_free_non_null (cl);
1374 * Check if some client is monitoring PUT messages and notify
1375 * them in that case.
1377 * @param options Options, for instance RecordRoute, DemultiplexEverywhere.
1378 * @param type The type of data in the request.
1379 * @param hop_count Hop count so far.
1380 * @param path_length number of entries in path (or 0 if not recorded).
1381 * @param path peers on the PUT path (or NULL if not recorded).
1382 * @param desired_replication_level Desired replication level.
1383 * @param exp Expiration time of the data.
1384 * @param key Key under which data is to be stored.
1385 * @param data Pointer to the data carried.
1386 * @param size Number of bytes in data.
1389 GDS_CLIENTS_process_put (uint32_t options,
1390 enum GNUNET_BLOCK_Type type,
1392 uint32_t desired_replication_level,
1393 unsigned int path_length,
1394 const struct GNUNET_PeerIdentity *path,
1395 struct GNUNET_TIME_Absolute exp,
1396 const struct GNUNET_HashCode * key,
1400 struct ClientMonitorRecord *m;
1401 struct ClientList **cl;
1402 unsigned int cl_size;
1406 for (m = monitor_head; NULL != m; m = m->next)
1408 if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) &&
1410 memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0))
1412 struct PendingMessage *pm;
1413 struct GNUNET_DHT_MonitorPutMessage *mmsg;
1414 struct GNUNET_PeerIdentity *msg_path;
1418 /* Don't send duplicates */
1419 for (i = 0; i < cl_size; i++)
1420 if (cl[i] == m->client)
1424 GNUNET_array_append (cl, cl_size, m->client);
1427 msize += path_length * sizeof (struct GNUNET_PeerIdentity);
1428 msize += sizeof (struct GNUNET_DHT_MonitorPutMessage);
1429 msize += sizeof (struct PendingMessage);
1430 pm = GNUNET_malloc (msize);
1431 mmsg = (struct GNUNET_DHT_MonitorPutMessage *) &pm[1];
1432 pm->msg = (struct GNUNET_MessageHeader *) mmsg;
1433 mmsg->header.size = htons (msize - sizeof (struct PendingMessage));
1434 mmsg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_MONITOR_PUT);
1435 mmsg->options = htonl(options);
1436 mmsg->type = htonl(type);
1437 mmsg->hop_count = htonl(hop_count);
1438 mmsg->desired_replication_level = htonl(desired_replication_level);
1439 mmsg->put_path_length = htonl(path_length);
1440 msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1];
1441 if (path_length > 0)
1443 memcpy (msg_path, path,
1444 path_length * sizeof (struct GNUNET_PeerIdentity));
1446 mmsg->expiration_time = GNUNET_TIME_absolute_hton(exp);
1447 memcpy (&mmsg->key, key, sizeof (struct GNUNET_HashCode));
1449 memcpy (&msg_path[path_length], data, size);
1450 add_pending_message (m->client, pm);
1453 GNUNET_free_non_null (cl);
1458 * Initialize client subsystem.
1460 * @param server the initialized server
1463 GDS_CLIENTS_init (struct GNUNET_SERVER_Handle *server)
1465 static struct GNUNET_SERVER_MessageHandler plugin_handlers[] = {
1466 {&handle_dht_local_put, NULL,
1467 GNUNET_MESSAGE_TYPE_DHT_CLIENT_PUT, 0},
1468 {&handle_dht_local_get, NULL,
1469 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET, 0},
1470 {&handle_dht_local_get_stop, NULL,
1471 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET_STOP,
1472 sizeof (struct GNUNET_DHT_ClientGetStopMessage)},
1473 {&handle_dht_local_monitor, NULL,
1474 GNUNET_MESSAGE_TYPE_DHT_MONITOR_START,
1475 sizeof (struct GNUNET_DHT_MonitorStartStopMessage)},
1476 {&handle_dht_local_monitor_stop, NULL,
1477 GNUNET_MESSAGE_TYPE_DHT_MONITOR_STOP,
1478 sizeof (struct GNUNET_DHT_MonitorStartStopMessage)},
1479 {&handle_dht_local_get_result_seen, NULL,
1480 GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET_RESULTS_KNOWN, 0},
1483 forward_map = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
1484 retry_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
1485 GNUNET_SERVER_add_handlers (server, plugin_handlers);
1486 GNUNET_SERVER_disconnect_notify (server, &handle_client_disconnect, NULL);
1491 * Shutdown client subsystem.
1496 GNUNET_assert (client_head == NULL);
1497 GNUNET_assert (client_tail == NULL);
1498 if (GNUNET_SCHEDULER_NO_TASK != retry_task)
1500 GNUNET_SCHEDULER_cancel (retry_task);
1501 retry_task = GNUNET_SCHEDULER_NO_TASK;
1503 if (NULL != retry_heap)
1505 GNUNET_assert (0 == GNUNET_CONTAINER_heap_get_size (retry_heap));
1506 GNUNET_CONTAINER_heap_destroy (retry_heap);
1509 if (NULL != forward_map)
1511 GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (forward_map));
1512 GNUNET_CONTAINER_multihashmap_destroy (forward_map);
1517 /* end of gnunet-service-dht_clients.c */