/* This file is part of GNUnet. Copyright (C) 2009, 2010, 2011, 2016, 2017 GNUnet e.V. GNUnet is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. GNUnet is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program. If not, see . SPDX-License-Identifier: AGPL3.0-or-later */ /** * @file dht/gnunet-service-dht_clients.c * @brief GNUnet DHT service's client management code * @author Christian Grothoff * @author Nathan Evans */ #include "platform.h" #include "gnunet_constants.h" #include "gnunet_protocols.h" #include "gnunet_statistics_service.h" #include "gnunet-service-dht.h" #include "gnunet-service-dht_datacache.h" #include "gnunet-service-dht_neighbours.h" #include "dht.h" /** * Should routing details be logged to stderr (for debugging)? */ #define LOG_TRAFFIC(kind,...) GNUNET_log_from (kind, "dht-traffic",__VA_ARGS__) #define LOG(kind,...) GNUNET_log_from (kind, "dht-clients",__VA_ARGS__) /** * Struct containing information about a client, * handle to connect to it, and any pending messages * that need to be sent to it. */ struct ClientHandle; /** * Entry in the local forwarding map for a client's GET request. */ struct ClientQueryRecord { /** * The key this request was about */ struct GNUNET_HashCode key; /** * Kept in a DLL with @e client. */ struct ClientQueryRecord *next; /** * Kept in a DLL with @e client. */ struct ClientQueryRecord *prev; /** * Client responsible for the request. */ struct ClientHandle *ch; /** * Extended query (see gnunet_block_lib.h), allocated at the end of this struct. */ const void *xquery; /** * Replies we have already seen for this request. */ struct GNUNET_HashCode *seen_replies; /** * Pointer to this nodes heap location in the retry-heap (for fast removal) */ struct GNUNET_CONTAINER_HeapNode *hnode; /** * What's the delay between re-try operations that we currently use for this * request? */ struct GNUNET_TIME_Relative retry_frequency; /** * What's the next time we should re-try this request? */ struct GNUNET_TIME_Absolute retry_time; /** * The unique identifier of this request */ uint64_t unique_id; /** * Number of bytes in xquery. */ size_t xquery_size; /** * Number of entries in 'seen_replies'. */ unsigned int seen_replies_count; /** * Desired replication level */ uint32_t replication; /** * Any message options for this request */ uint32_t msg_options; /** * The type for the data for the GET request. */ enum GNUNET_BLOCK_Type type; }; /** * Struct containing paremeters of monitoring requests. */ struct ClientMonitorRecord { /** * Next element in DLL. */ struct ClientMonitorRecord *next; /** * Previous element in DLL. */ struct ClientMonitorRecord *prev; /** * Type of blocks that are of interest */ enum GNUNET_BLOCK_Type type; /** * Key of data of interest, NULL for all. */ struct GNUNET_HashCode *key; /** * Flag whether to notify about GET messages. */ int16_t get; /** * Flag whether to notify about GET_REPONSE messages. */ int16_t get_resp; /** * Flag whether to notify about PUT messages. */ uint16_t put; /** * Client to notify of these requests. */ struct ClientHandle *ch; }; /** * Struct containing information about a client, * handle to connect to it, and any pending messages * that need to be sent to it. */ struct ClientHandle { /** * Linked list of active queries of this client. */ struct ClientQueryRecord *cqr_head; /** * Linked list of active queries of this client. */ struct ClientQueryRecord *cqr_tail; /** * The handle to this client */ struct GNUNET_SERVICE_Client *client; /** * The message queue to this client */ struct GNUNET_MQ_Handle *mq; }; /** * Our handle to the BLOCK library. */ struct GNUNET_BLOCK_Context *GDS_block_context; /** * Handle for the statistics service. */ struct GNUNET_STATISTICS_Handle *GDS_stats; /** * Handle for the service. */ struct GNUNET_SERVICE_Handle *GDS_service; /** * The configuration the DHT service is running with */ const struct GNUNET_CONFIGURATION_Handle *GDS_cfg; /** * List of active monitoring requests. */ static struct ClientMonitorRecord *monitor_head; /** * List of active monitoring requests. */ static struct ClientMonitorRecord *monitor_tail; /** * Hashmap for fast key based lookup, maps keys to `struct ClientQueryRecord` entries. */ static struct GNUNET_CONTAINER_MultiHashMap *forward_map; /** * Heap with all of our client's request, sorted by retry time (earliest on top). */ static struct GNUNET_CONTAINER_Heap *retry_heap; /** * Task that re-transmits requests (using retry_heap). */ static struct GNUNET_SCHEDULER_Task *retry_task; /** * Free data structures associated with the given query. * * @param record record to remove */ static void remove_client_record (struct ClientQueryRecord *record) { struct ClientHandle *ch = record->ch; GNUNET_CONTAINER_DLL_remove (ch->cqr_head, ch->cqr_tail, record); GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multihashmap_remove (forward_map, &record->key, record)); if (NULL != record->hnode) GNUNET_CONTAINER_heap_remove_node (record->hnode); GNUNET_array_grow (record->seen_replies, record->seen_replies_count, 0); GNUNET_free (record); } /** * Functions with this signature are called whenever a local client is * connects to us. * * @param cls closure (NULL for dht) * @param client identification of the client * @param mq message queue for talking to @a client * @return our `struct ClientHandle` for @a client */ static void * client_connect_cb (void *cls, struct GNUNET_SERVICE_Client *client, struct GNUNET_MQ_Handle *mq) { struct ClientHandle *ch; ch = GNUNET_new (struct ClientHandle); ch->client = client; ch->mq = mq; return ch; } /** * Functions with this signature are called whenever a client * is disconnected on the network level. * * @param cls closure (NULL for dht) * @param client identification of the client * @param app_ctx our `struct ClientHandle` for @a client */ static void client_disconnect_cb (void *cls, struct GNUNET_SERVICE_Client *client, void *app_ctx) { struct ClientHandle *ch = app_ctx; struct ClientQueryRecord *cqr; struct ClientMonitorRecord *monitor; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Local client %p disconnects\n", ch); monitor = monitor_head; while (NULL != monitor) { if (monitor->ch == ch) { struct ClientMonitorRecord *next; next = monitor->next; GNUNET_free_non_null (monitor->key); GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, monitor); GNUNET_free (monitor); monitor = next; } else { monitor = monitor->next; } } while (NULL != (cqr = ch->cqr_head)) remove_client_record (cqr); GNUNET_free (ch); } /** * Route the given request via the DHT. This includes updating * the bloom filter and retransmission times, building the P2P * message and initiating the routing operation. */ static void transmit_request (struct ClientQueryRecord *cqr) { struct GNUNET_BLOCK_Group *bg; struct GNUNET_CONTAINER_BloomFilter *peer_bf; GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# GET requests from clients injected"), 1, GNUNET_NO); bg = GNUNET_BLOCK_group_create (GDS_block_context, cqr->type, GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, UINT32_MAX), NULL, 0, "seen-set-size", cqr->seen_replies_count, NULL); GNUNET_BLOCK_group_set_seen (bg, cqr->seen_replies, cqr->seen_replies_count); peer_bf = GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, GNUNET_CONSTANTS_BLOOMFILTER_K); LOG (GNUNET_ERROR_TYPE_DEBUG, "Initiating GET for %s, replication %u, already have %u replies\n", GNUNET_h2s (&cqr->key), cqr->replication, cqr->seen_replies_count); GDS_NEIGHBOURS_handle_get (cqr->type, cqr->msg_options, cqr->replication, 0 /* hop count */ , &cqr->key, cqr->xquery, cqr->xquery_size, bg, peer_bf); GNUNET_BLOCK_group_destroy (bg); GNUNET_CONTAINER_bloomfilter_free (peer_bf); /* exponential back-off for retries. * max GNUNET_TIME_STD_EXPONENTIAL_BACKOFF_THRESHOLD (15 min) */ cqr->retry_frequency = GNUNET_TIME_STD_BACKOFF (cqr->retry_frequency); cqr->retry_time = GNUNET_TIME_relative_to_absolute (cqr->retry_frequency); } /** * Task that looks at the #retry_heap and transmits all of the requests * on the heap that are ready for transmission. Then re-schedules * itself (unless the heap is empty). * * @param cls unused */ static void transmit_next_request_task (void *cls) { struct ClientQueryRecord *cqr; struct GNUNET_TIME_Relative delay; retry_task = NULL; while (NULL != (cqr = GNUNET_CONTAINER_heap_remove_root (retry_heap))) { cqr->hnode = NULL; delay = GNUNET_TIME_absolute_get_remaining (cqr->retry_time); if (delay.rel_value_us > 0) { cqr->hnode = GNUNET_CONTAINER_heap_insert (retry_heap, cqr, cqr->retry_time.abs_value_us); retry_task = GNUNET_SCHEDULER_add_at (cqr->retry_time, &transmit_next_request_task, NULL); return; } transmit_request (cqr); cqr->hnode = GNUNET_CONTAINER_heap_insert (retry_heap, cqr, cqr->retry_time.abs_value_us); } } /** * Check DHT PUT messages from the client. * * @param cls the client we received this message from * @param dht_msg the actual message received * @return #GNUNET_OK (always) */ static int check_dht_local_put (void *cls, const struct GNUNET_DHT_ClientPutMessage *dht_msg) { /* always well-formed */ return GNUNET_OK; } /** * Handler for PUT messages. * * @param cls the client we received this message from * @param dht_msg the actual message received */ static void handle_dht_local_put (void *cls, const struct GNUNET_DHT_ClientPutMessage *dht_msg) { struct ClientHandle *ch = cls; struct GNUNET_CONTAINER_BloomFilter *peer_bf; uint16_t size; size = ntohs (dht_msg->header.size); GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# PUT requests received from clients"), 1, GNUNET_NO); LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "CLIENT-PUT %s\n", GNUNET_h2s_full (&dht_msg->key)); /* give to local clients */ LOG (GNUNET_ERROR_TYPE_DEBUG, "Handling local PUT of %u-bytes for query %s\n", size - sizeof (struct GNUNET_DHT_ClientPutMessage), GNUNET_h2s (&dht_msg->key)); GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (dht_msg->expiration), &dht_msg->key, 0, NULL, 0, NULL, ntohl (dht_msg->type), size - sizeof (struct GNUNET_DHT_ClientPutMessage), &dht_msg[1]); /* store locally */ GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (dht_msg->expiration), &dht_msg->key, 0, NULL, ntohl (dht_msg->type), size - sizeof (struct GNUNET_DHT_ClientPutMessage), &dht_msg[1]); /* route to other peers */ peer_bf = GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, GNUNET_CONSTANTS_BLOOMFILTER_K); GDS_NEIGHBOURS_handle_put (ntohl (dht_msg->type), ntohl (dht_msg->options), ntohl (dht_msg->desired_replication_level), GNUNET_TIME_absolute_ntoh (dht_msg->expiration), 0 /* hop count */, peer_bf, &dht_msg->key, 0, NULL, &dht_msg[1], size - sizeof (struct GNUNET_DHT_ClientPutMessage)); GDS_CLIENTS_process_put (ntohl (dht_msg->options), ntohl (dht_msg->type), 0, ntohl (dht_msg->desired_replication_level), 1, GDS_NEIGHBOURS_get_id(), GNUNET_TIME_absolute_ntoh (dht_msg->expiration), &dht_msg->key, &dht_msg[1], size - sizeof (struct GNUNET_DHT_ClientPutMessage)); GNUNET_CONTAINER_bloomfilter_free (peer_bf); GNUNET_SERVICE_client_continue (ch->client); } /** * Check DHT GET messages from the client. * * @param cls the client we received this message from * @param message the actual message received * @return #GNUNET_OK (always) */ static int check_dht_local_get (void *cls, const struct GNUNET_DHT_ClientGetMessage *get) { /* always well-formed */ return GNUNET_OK; } /** * Handle a result from local datacache for a GET operation. * * @param cls the `struct ClientHandle` of the client doing the query * @param type type of the block * @param expiration_time when does the content expire * @param key key for the content * @param put_path_length number of entries in @a put_path * @param put_path peers the original PUT traversed (if tracked) * @param get_path_length number of entries in @a get_path * @param get_path peers this reply has traversed so far (if tracked) * @param data payload of the reply * @param data_size number of bytes in @a data */ static void handle_local_result (void *cls, enum GNUNET_BLOCK_Type type, struct GNUNET_TIME_Absolute expiration_time, const struct GNUNET_HashCode *key, unsigned int put_path_length, const struct GNUNET_PeerIdentity *put_path, unsigned int get_path_length, const struct GNUNET_PeerIdentity *get_path, const void *data, size_t data_size) { // FIXME: this needs some clean up: inline the function, // possibly avoid even looking up the client! GDS_CLIENTS_handle_reply (expiration_time, key, 0, NULL, put_path_length, put_path, type, data_size, data); } /** * Handler for DHT GET messages from the client. * * @param cls the client we received this message from * @param message the actual message received */ static void handle_dht_local_get (void *cls, const struct GNUNET_DHT_ClientGetMessage *get) { struct ClientHandle *ch = cls; struct ClientQueryRecord *cqr; size_t xquery_size; const char *xquery; uint16_t size; size = ntohs (get->header.size); xquery_size = size - sizeof (struct GNUNET_DHT_ClientGetMessage); xquery = (const char *) &get[1]; GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# GET requests received from clients"), 1, GNUNET_NO); LOG (GNUNET_ERROR_TYPE_DEBUG, "Received GET request for %s from local client %p, xq: %.*s\n", GNUNET_h2s (&get->key), ch->client, xquery_size, xquery); LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "CLIENT-GET %s\n", GNUNET_h2s_full (&get->key)); cqr = GNUNET_malloc (sizeof (struct ClientQueryRecord) + xquery_size); cqr->key = get->key; cqr->ch = ch; cqr->xquery = (void *) &cqr[1]; GNUNET_memcpy (&cqr[1], xquery, xquery_size); cqr->hnode = GNUNET_CONTAINER_heap_insert (retry_heap, cqr, 0); cqr->retry_frequency = GNUNET_TIME_UNIT_SECONDS; cqr->retry_time = GNUNET_TIME_absolute_get (); cqr->unique_id = get->unique_id; cqr->xquery_size = xquery_size; cqr->replication = ntohl (get->desired_replication_level); cqr->msg_options = ntohl (get->options); cqr->type = ntohl (get->type); GNUNET_CONTAINER_DLL_insert (ch->cqr_head, ch->cqr_tail, cqr); GNUNET_CONTAINER_multihashmap_put (forward_map, &cqr->key, cqr, GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE); GDS_CLIENTS_process_get (ntohl (get->options), ntohl (get->type), 0, ntohl (get->desired_replication_level), 1, GDS_NEIGHBOURS_get_id(), &get->key); /* start remote requests */ if (NULL != retry_task) GNUNET_SCHEDULER_cancel (retry_task); retry_task = GNUNET_SCHEDULER_add_now (&transmit_next_request_task, NULL); /* perform local lookup */ GDS_DATACACHE_handle_get (&get->key, cqr->type, cqr->xquery, xquery_size, NULL, &handle_local_result, ch); GNUNET_SERVICE_client_continue (ch->client); } /** * Closure for #find_by_unique_id(). */ struct FindByUniqueIdContext { /** * Where to store the result, if found. */ struct ClientQueryRecord *cqr; uint64_t unique_id; }; /** * Function called for each existing DHT record for the given * query. Checks if it matches the UID given in the closure * and if so returns the entry as a result. * * @param cls the search context * @param key query for the lookup (not used) * @param value the `struct ClientQueryRecord` * @return #GNUNET_YES to continue iteration (result not yet found) */ static int find_by_unique_id (void *cls, const struct GNUNET_HashCode *key, void *value) { struct FindByUniqueIdContext *fui_ctx = cls; struct ClientQueryRecord *cqr = value; if (cqr->unique_id != fui_ctx->unique_id) return GNUNET_YES; fui_ctx->cqr = cqr; return GNUNET_NO; } /** * Check "GET result seen" messages from the client. * * @param cls the client we received this message from * @param message the actual message received * @return #GNUNET_OK if @a seen is well-formed */ static int check_dht_local_get_result_seen (void *cls, const struct GNUNET_DHT_ClientGetResultSeenMessage *seen) { uint16_t size; unsigned int hash_count; size = ntohs (seen->header.size); hash_count = (size - sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage)) / sizeof (struct GNUNET_HashCode); if (size != sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage) + hash_count * sizeof (struct GNUNET_HashCode)) { GNUNET_break (0); return GNUNET_SYSERR; } return GNUNET_OK; } /** * Handler for "GET result seen" messages from the client. * * @param cls the client we received this message from * @param message the actual message received */ static void handle_dht_local_get_result_seen (void *cls, const struct GNUNET_DHT_ClientGetResultSeenMessage *seen) { struct ClientHandle *ch = cls; uint16_t size; unsigned int hash_count; unsigned int old_count; const struct GNUNET_HashCode *hc; struct FindByUniqueIdContext fui_ctx; struct ClientQueryRecord *cqr; size = ntohs (seen->header.size); hash_count = (size - sizeof (struct GNUNET_DHT_ClientGetResultSeenMessage)) / sizeof (struct GNUNET_HashCode); hc = (const struct GNUNET_HashCode*) &seen[1]; fui_ctx.unique_id = seen->unique_id; fui_ctx.cqr = NULL; GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, &seen->key, &find_by_unique_id, &fui_ctx); if (NULL == (cqr = fui_ctx.cqr)) { GNUNET_break (0); GNUNET_SERVICE_client_drop (ch->client); return; } /* finally, update 'seen' list */ old_count = cqr->seen_replies_count; GNUNET_array_grow (cqr->seen_replies, cqr->seen_replies_count, cqr->seen_replies_count + hash_count); GNUNET_memcpy (&cqr->seen_replies[old_count], hc, sizeof (struct GNUNET_HashCode) * hash_count); } /** * Closure for #remove_by_unique_id(). */ struct RemoveByUniqueIdContext { /** * Client that issued the removal request. */ struct ClientHandle *ch; /** * Unique ID of the request. */ uint64_t unique_id; }; /** * Iterator over hash map entries that frees all entries * that match the given client and unique ID. * * @param cls unique ID and client to search for in source routes * @param key current key code * @param value value in the hash map, a ClientQueryRecord * @return #GNUNET_YES (we should continue to iterate) */ static int remove_by_unique_id (void *cls, const struct GNUNET_HashCode *key, void *value) { const struct RemoveByUniqueIdContext *ctx = cls; struct ClientQueryRecord *cqr = value; if (cqr->unique_id != ctx->unique_id) return GNUNET_YES; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Removing client %p's record for key %s (by unique id)\n", ctx->ch->client, GNUNET_h2s (key)); remove_client_record (cqr); return GNUNET_YES; } /** * Handler for any generic DHT stop messages, calls the appropriate handler * depending on message type (if processed locally) * * @param cls client we received this message from * @param message the actual message received * */ static void handle_dht_local_get_stop (void *cls, const struct GNUNET_DHT_ClientGetStopMessage *dht_stop_msg) { struct ClientHandle *ch = cls; struct RemoveByUniqueIdContext ctx; GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# GET STOP requests received from clients"), 1, GNUNET_NO); LOG (GNUNET_ERROR_TYPE_DEBUG, "Received GET STOP request for %s from local client %p\n", GNUNET_h2s (&dht_stop_msg->key), ch->client); ctx.ch = ch; ctx.unique_id = dht_stop_msg->unique_id; GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, &dht_stop_msg->key, &remove_by_unique_id, &ctx); GNUNET_SERVICE_client_continue (ch->client); } /** * Handler for monitor start messages * * @param cls the client we received this message from * @param msg the actual message received * */ static void handle_dht_local_monitor (void *cls, const struct GNUNET_DHT_MonitorStartStopMessage *msg) { struct ClientHandle *ch = cls; struct ClientMonitorRecord *r; r = GNUNET_new (struct ClientMonitorRecord); r->ch = ch; r->type = ntohl (msg->type); r->get = ntohs (msg->get); r->get_resp = ntohs (msg->get_resp); r->put = ntohs (msg->put); if (0 == ntohs (msg->filter_key)) { r->key = NULL; } else { r->key = GNUNET_new (struct GNUNET_HashCode); GNUNET_memcpy (r->key, &msg->key, sizeof (struct GNUNET_HashCode)); } GNUNET_CONTAINER_DLL_insert (monitor_head, monitor_tail, r); GNUNET_SERVICE_client_continue (ch->client); } /** * Handler for monitor stop messages * * @param cls the client we received this message from * @param msg the actual message received */ static void handle_dht_local_monitor_stop (void *cls, const struct GNUNET_DHT_MonitorStartStopMessage *msg) { struct ClientHandle *ch = cls; struct ClientMonitorRecord *r; int keys_match; GNUNET_SERVICE_client_continue (ch->client); for (r = monitor_head; NULL != r; r = r->next) { if (NULL == r->key) { keys_match = (0 == ntohs(msg->filter_key)); } else { keys_match = ( (0 != ntohs(msg->filter_key)) && (! memcmp (r->key, &msg->key, sizeof(struct GNUNET_HashCode))) ); } if ( (ch == r->ch) && (ntohl(msg->type) == r->type) && (r->get == msg->get) && (r->get_resp == msg->get_resp) && (r->put == msg->put) && keys_match ) { GNUNET_CONTAINER_DLL_remove (monitor_head, monitor_tail, r); GNUNET_free_non_null (r->key); GNUNET_free (r); return; /* Delete only ONE entry */ } } } /** * Closure for #forward_reply() */ struct ForwardReplyContext { /** * Expiration time of the reply. */ struct GNUNET_TIME_Absolute expiration; /** * GET path taken. */ const struct GNUNET_PeerIdentity *get_path; /** * PUT path taken. */ const struct GNUNET_PeerIdentity *put_path; /** * Embedded payload. */ const void *data; /** * Number of bytes in data. */ size_t data_size; /** * Number of entries in @e get_path. */ unsigned int get_path_length; /** * Number of entries in @e put_path. */ unsigned int put_path_length; /** * Type of the data. */ enum GNUNET_BLOCK_Type type; }; /** * Iterator over hash map entries that send a given reply to * each of the matching clients. With some tricky recycling * of the buffer. * * @param cls the 'struct ForwardReplyContext' * @param key current key * @param value value in the hash map, a ClientQueryRecord * @return #GNUNET_YES (we should continue to iterate), * if the result is mal-formed, #GNUNET_NO */ static int forward_reply (void *cls, const struct GNUNET_HashCode *key, void *value) { struct ForwardReplyContext *frc = cls; struct ClientQueryRecord *record = value; struct GNUNET_MQ_Envelope *env; struct GNUNET_DHT_ClientResultMessage *reply; enum GNUNET_BLOCK_EvaluationResult eval; int do_free; struct GNUNET_HashCode ch; struct GNUNET_PeerIdentity *paths; LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "CLIENT-RESULT %s\n", GNUNET_h2s_full (key)); if ( (record->type != GNUNET_BLOCK_TYPE_ANY) && (record->type != frc->type)) { LOG (GNUNET_ERROR_TYPE_DEBUG, "Record type mismatch, not passing request for key %s to local client\n", GNUNET_h2s (key)); GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# Key match, type mismatches in REPLY to CLIENT"), 1, GNUNET_NO); return GNUNET_YES; /* type mismatch */ } GNUNET_CRYPTO_hash (frc->data, frc->data_size, &ch); for (unsigned int i = 0; i < record->seen_replies_count; i++) if (0 == memcmp (&record->seen_replies[i], &ch, sizeof (struct GNUNET_HashCode))) { LOG (GNUNET_ERROR_TYPE_DEBUG, "Duplicate reply, not passing request for key %s to local client\n", GNUNET_h2s (key)); GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# Duplicate REPLIES to CLIENT request dropped"), 1, GNUNET_NO); return GNUNET_YES; /* duplicate */ } eval = GNUNET_BLOCK_evaluate (GDS_block_context, record->type, NULL, GNUNET_BLOCK_EO_NONE, key, record->xquery, record->xquery_size, frc->data, frc->data_size); LOG (GNUNET_ERROR_TYPE_DEBUG, "Evaluation result is %d for key %s for local client's query\n", (int) eval, GNUNET_h2s (key)); switch (eval) { case GNUNET_BLOCK_EVALUATION_OK_LAST: do_free = GNUNET_YES; break; case GNUNET_BLOCK_EVALUATION_OK_MORE: GNUNET_array_append (record->seen_replies, record->seen_replies_count, ch); do_free = GNUNET_NO; break; case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE: /* should be impossible to encounter here */ GNUNET_break (0); return GNUNET_YES; case GNUNET_BLOCK_EVALUATION_RESULT_INVALID: GNUNET_break_op (0); return GNUNET_NO; case GNUNET_BLOCK_EVALUATION_REQUEST_VALID: GNUNET_break (0); return GNUNET_NO; case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID: GNUNET_break (0); return GNUNET_NO; case GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT: return GNUNET_YES; case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED: GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("Unsupported block type (%u) in request!\n"), record->type); return GNUNET_NO; default: GNUNET_break (0); return GNUNET_NO; } GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# RESULTS queued for clients"), 1, GNUNET_NO); env = GNUNET_MQ_msg_extra (reply, frc->data_size + (frc->get_path_length + frc->put_path_length) * sizeof (struct GNUNET_PeerIdentity), GNUNET_MESSAGE_TYPE_DHT_CLIENT_RESULT); reply->type = htonl (frc->type); reply->get_path_length = htonl (frc->get_path_length); reply->put_path_length = htonl (frc->put_path_length); reply->unique_id = record->unique_id; reply->expiration = GNUNET_TIME_absolute_hton (frc->expiration); reply->key = *key; paths = (struct GNUNET_PeerIdentity *) &reply[1]; GNUNET_memcpy (paths, frc->put_path, sizeof (struct GNUNET_PeerIdentity) * frc->put_path_length); GNUNET_memcpy (&paths[frc->put_path_length], frc->get_path, sizeof (struct GNUNET_PeerIdentity) * frc->get_path_length); GNUNET_memcpy (&paths[frc->get_path_length + frc->put_path_length], frc->data, frc->data_size); LOG (GNUNET_ERROR_TYPE_DEBUG, "Sending reply to query %s for client %p\n", GNUNET_h2s (key), record->ch->client); GNUNET_MQ_send (record->ch->mq, env); if (GNUNET_YES == do_free) remove_client_record (record); return GNUNET_YES; } /** * Handle a reply we've received from another peer. If the reply * matches any of our pending queries, forward it to the respective * client(s). * * @param expiration when will the reply expire * @param key the query this reply is for * @param get_path_length number of peers in @a get_path * @param get_path path the reply took on get * @param put_path_length number of peers in @a put_path * @param put_path path the reply took on put * @param type type of the reply * @param data_size number of bytes in @a data * @param data application payload data */ void GDS_CLIENTS_handle_reply (struct GNUNET_TIME_Absolute expiration, const struct GNUNET_HashCode *key, unsigned int get_path_length, const struct GNUNET_PeerIdentity *get_path, unsigned int put_path_length, const struct GNUNET_PeerIdentity *put_path, enum GNUNET_BLOCK_Type type, size_t data_size, const void *data) { struct ForwardReplyContext frc; size_t msize; msize = sizeof (struct GNUNET_DHT_ClientResultMessage) + data_size + (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity); if (msize >= GNUNET_MAX_MESSAGE_SIZE) { GNUNET_break (0); return; } if (NULL == GNUNET_CONTAINER_multihashmap_get (forward_map, key)) { LOG (GNUNET_ERROR_TYPE_DEBUG, "No matching client for reply for key %s\n", GNUNET_h2s (key)); GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# REPLIES ignored for CLIENTS (no match)"), 1, GNUNET_NO); return; /* no matching request, fast exit! */ } frc.expiration = expiration; frc.get_path = get_path; frc.put_path = put_path; frc.data = data; frc.data_size = data_size; frc.get_path_length = get_path_length; frc.put_path_length = put_path_length; frc.type = type; LOG (GNUNET_ERROR_TYPE_DEBUG, "Forwarding reply for key %s to client\n", GNUNET_h2s (key)); GNUNET_CONTAINER_multihashmap_get_multiple (forward_map, key, &forward_reply, &frc); } /** * Check if some client is monitoring GET messages and notify * them in that case. * * @param options Options, for instance RecordRoute, DemultiplexEverywhere. * @param type The type of data in the request. * @param hop_count Hop count so far. * @param path_length number of entries in path (or 0 if not recorded). * @param path peers on the GET path (or NULL if not recorded). * @param desired_replication_level Desired replication level. * @param key Key of the requested data. */ void GDS_CLIENTS_process_get (uint32_t options, enum GNUNET_BLOCK_Type type, uint32_t hop_count, uint32_t desired_replication_level, unsigned int path_length, const struct GNUNET_PeerIdentity *path, const struct GNUNET_HashCode * key) { struct ClientMonitorRecord *m; struct ClientHandle **cl; unsigned int cl_size; cl = NULL; cl_size = 0; for (m = monitor_head; NULL != m; m = m->next) { if ( ( (GNUNET_BLOCK_TYPE_ANY == m->type) || (m->type == type) ) && ( (NULL == m->key) || (0 == memcmp (key, m->key, sizeof(struct GNUNET_HashCode))) ) ) { struct GNUNET_MQ_Envelope *env; struct GNUNET_DHT_MonitorGetMessage *mmsg; struct GNUNET_PeerIdentity *msg_path; size_t msize; unsigned int i; /* Don't send duplicates */ for (i = 0; i < cl_size; i++) if (cl[i] == m->ch) break; if (i < cl_size) continue; GNUNET_array_append (cl, cl_size, m->ch); msize = path_length * sizeof (struct GNUNET_PeerIdentity); env = GNUNET_MQ_msg_extra (mmsg, msize, GNUNET_MESSAGE_TYPE_DHT_MONITOR_GET); mmsg->options = htonl(options); mmsg->type = htonl(type); mmsg->hop_count = htonl(hop_count); mmsg->desired_replication_level = htonl(desired_replication_level); mmsg->get_path_length = htonl(path_length); mmsg->key = *key; msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1]; GNUNET_memcpy (msg_path, path, path_length * sizeof (struct GNUNET_PeerIdentity)); GNUNET_MQ_send (m->ch->mq, env); } } GNUNET_free_non_null (cl); } /** * Check if some client is monitoring GET RESP messages and notify * them in that case. * * @param type The type of data in the result. * @param get_path Peers on GET path (or NULL if not recorded). * @param get_path_length number of entries in get_path. * @param put_path peers on the PUT path (or NULL if not recorded). * @param put_path_length number of entries in get_path. * @param exp Expiration time of the data. * @param key Key of the data. * @param data Pointer to the result data. * @param size Number of bytes in @a data. */ void GDS_CLIENTS_process_get_resp (enum GNUNET_BLOCK_Type type, const struct GNUNET_PeerIdentity *get_path, unsigned int get_path_length, const struct GNUNET_PeerIdentity *put_path, unsigned int put_path_length, struct GNUNET_TIME_Absolute exp, const struct GNUNET_HashCode * key, const void *data, size_t size) { struct ClientMonitorRecord *m; struct ClientHandle **cl; unsigned int cl_size; cl = NULL; cl_size = 0; for (m = monitor_head; NULL != m; m = m->next) { if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) && (NULL == m->key || memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0)) { struct GNUNET_MQ_Envelope *env; struct GNUNET_DHT_MonitorGetRespMessage *mmsg; struct GNUNET_PeerIdentity *path; size_t msize; unsigned int i; /* Don't send duplicates */ for (i = 0; i < cl_size; i++) if (cl[i] == m->ch) break; if (i < cl_size) continue; GNUNET_array_append (cl, cl_size, m->ch); msize = size; msize += (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity); env = GNUNET_MQ_msg_extra (mmsg, msize, GNUNET_MESSAGE_TYPE_DHT_MONITOR_GET_RESP); mmsg->type = htonl(type); mmsg->put_path_length = htonl(put_path_length); mmsg->get_path_length = htonl(get_path_length); mmsg->expiration_time = GNUNET_TIME_absolute_hton(exp); mmsg->key = *key; path = (struct GNUNET_PeerIdentity *) &mmsg[1]; GNUNET_memcpy (path, put_path, put_path_length * sizeof (struct GNUNET_PeerIdentity)); GNUNET_memcpy (path, get_path, get_path_length * sizeof (struct GNUNET_PeerIdentity)); GNUNET_memcpy (&path[get_path_length], data, size); GNUNET_MQ_send (m->ch->mq, env); } } GNUNET_free_non_null (cl); } /** * Check if some client is monitoring PUT messages and notify * them in that case. * * @param options Options, for instance RecordRoute, DemultiplexEverywhere. * @param type The type of data in the request. * @param hop_count Hop count so far. * @param path_length number of entries in path (or 0 if not recorded). * @param path peers on the PUT path (or NULL if not recorded). * @param desired_replication_level Desired replication level. * @param exp Expiration time of the data. * @param key Key under which data is to be stored. * @param data Pointer to the data carried. * @param size Number of bytes in data. */ void GDS_CLIENTS_process_put (uint32_t options, enum GNUNET_BLOCK_Type type, uint32_t hop_count, uint32_t desired_replication_level, unsigned int path_length, const struct GNUNET_PeerIdentity *path, struct GNUNET_TIME_Absolute exp, const struct GNUNET_HashCode *key, const void *data, size_t size) { struct ClientMonitorRecord *m; struct ClientHandle **cl; unsigned int cl_size; cl = NULL; cl_size = 0; for (m = monitor_head; NULL != m; m = m->next) { if ((GNUNET_BLOCK_TYPE_ANY == m->type || m->type == type) && (NULL == m->key || memcmp (key, m->key, sizeof(struct GNUNET_HashCode)) == 0)) { struct GNUNET_MQ_Envelope *env; struct GNUNET_DHT_MonitorPutMessage *mmsg; struct GNUNET_PeerIdentity *msg_path; size_t msize; unsigned int i; /* Don't send duplicates */ for (i = 0; i < cl_size; i++) if (cl[i] == m->ch) break; if (i < cl_size) continue; GNUNET_array_append (cl, cl_size, m->ch); msize = size; msize += path_length * sizeof (struct GNUNET_PeerIdentity); env = GNUNET_MQ_msg_extra (mmsg, msize, GNUNET_MESSAGE_TYPE_DHT_MONITOR_PUT); mmsg->options = htonl(options); mmsg->type = htonl(type); mmsg->hop_count = htonl(hop_count); mmsg->desired_replication_level = htonl (desired_replication_level); mmsg->put_path_length = htonl (path_length); mmsg->key = *key; mmsg->expiration_time = GNUNET_TIME_absolute_hton (exp); msg_path = (struct GNUNET_PeerIdentity *) &mmsg[1]; GNUNET_memcpy (msg_path, path, path_length * sizeof (struct GNUNET_PeerIdentity)); GNUNET_memcpy (&msg_path[path_length], data, size); GNUNET_MQ_send (m->ch->mq, env); } } GNUNET_free_non_null (cl); } /** * Initialize client subsystem. * * @param server the initialized server */ static void GDS_CLIENTS_init () { forward_map = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_YES); retry_heap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN); } /** * Shutdown client subsystem. */ static void GDS_CLIENTS_stop () { if (NULL != retry_task) { GNUNET_SCHEDULER_cancel (retry_task); retry_task = NULL; } } /** * Define "main" method using service macro. * * @param name name of the service, i.e. "dht" or "xdht" * @param run name of the initializaton method for the service */ #define GDS_DHT_SERVICE_INIT(name,run) \ GNUNET_SERVICE_MAIN \ (name, \ GNUNET_SERVICE_OPTION_NONE, \ run, \ &client_connect_cb, \ &client_disconnect_cb, \ NULL, \ GNUNET_MQ_hd_var_size (dht_local_put, \ GNUNET_MESSAGE_TYPE_DHT_CLIENT_PUT, \ struct GNUNET_DHT_ClientPutMessage, \ NULL), \ GNUNET_MQ_hd_var_size (dht_local_get, \ GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET, \ struct GNUNET_DHT_ClientGetMessage, \ NULL), \ GNUNET_MQ_hd_fixed_size (dht_local_get_stop, \ GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET_STOP, \ struct GNUNET_DHT_ClientGetStopMessage, \ NULL), \ GNUNET_MQ_hd_fixed_size (dht_local_monitor, \ GNUNET_MESSAGE_TYPE_DHT_MONITOR_START, \ struct GNUNET_DHT_MonitorStartStopMessage, \ NULL), \ GNUNET_MQ_hd_fixed_size (dht_local_monitor_stop, \ GNUNET_MESSAGE_TYPE_DHT_MONITOR_STOP, \ struct GNUNET_DHT_MonitorStartStopMessage, \ NULL), \ GNUNET_MQ_hd_var_size (dht_local_get_result_seen, \ GNUNET_MESSAGE_TYPE_DHT_CLIENT_GET_RESULTS_KNOWN, \ struct GNUNET_DHT_ClientGetResultSeenMessage , \ NULL), \ GNUNET_MQ_handler_end ()) /** * MINIMIZE heap size (way below 128k) since this process doesn't need much. */ void __attribute__ ((destructor)) GDS_CLIENTS_done () { if (NULL != retry_heap) { GNUNET_assert (0 == GNUNET_CONTAINER_heap_get_size (retry_heap)); GNUNET_CONTAINER_heap_destroy (retry_heap); retry_heap = NULL; } if (NULL != forward_map) { GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (forward_map)); GNUNET_CONTAINER_multihashmap_destroy (forward_map); forward_map = NULL; } } /* end of gnunet-service-dht_clients.c */