X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Finclude%2Fgnunet_dht_service.h;h=d9bbccbdf6f23e7749994ea2816d8330a5be500f;hb=6e626937fd5133188d2bd06f280a1b889219eef2;hp=dfb880b4af44c3cfa77962003d459ce27d7ad0df;hpb=b72f6ef6daf67fbd316c603ef7fe230edfc805a8;p=oweals%2Fgnunet.git diff --git a/src/include/gnunet_dht_service.h b/src/include/gnunet_dht_service.h index dfb880b4a..d9bbccbdf 100644 --- a/src/include/gnunet_dht_service.h +++ b/src/include/gnunet_dht_service.h @@ -1,33 +1,43 @@ /* This file is part of GNUnet - (C) 2004, 2005, 2006, 2008, 2009 Christian Grothoff (and other contributing authors) + Copyright (C) 2004-2013, 2016 GNUnet e.V. - GNUnet is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published - by the Free Software Foundation; either version 2, or (at your - option) any later version. + 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 - General Public License for more details. + 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 . - You should have received a copy of the GNU General Public License - along with GNUnet; see the file COPYING. If not, write to the - Free Software Foundation, Inc., 59 Temple Place - Suite 330, - Boston, MA 02111-1307, USA. + SPDX-License-Identifier: AGPL3.0-or-later */ /** - * @file include/gnunet_dht_service.h - * @brief API to the DHT service * @author Christian Grothoff + * + * @file + * API to the DHT service + * + * @defgroup dht DHT service + * Distributed Hash Table + * + * @see [Documentation](https://gnunet.org/developer-handbook-dht) + * + * @{ */ #ifndef GNUNET_DHT_SERVICE_H #define GNUNET_DHT_SERVICE_H #include "gnunet_util_lib.h" +#include "gnunet_block_lib.h" +#include "gnunet_hello_lib.h" #ifdef __cplusplus extern "C" @@ -38,139 +48,345 @@ extern "C" #endif +/** + * Default republication frequency for stored data in the DHT. + */ +#define GNUNET_DHT_DEFAULT_REPUBLISH_FREQUENCY GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 60) + + + /** * Connection to the DHT service. */ struct GNUNET_DHT_Handle; +/** + * Handle to control a get operation. + */ +struct GNUNET_DHT_GetHandle; + +/** + * Handle to control a find peer operation. + */ +struct GNUNET_DHT_FindPeerHandle; + + +/** + * Options for routing. + */ +enum GNUNET_DHT_RouteOption +{ + /** + * Default. Do nothing special. + */ + GNUNET_DHT_RO_NONE = 0, + + /** + * Each peer along the way should look at 'enc' (otherwise + * only the k-peers closest to the key should look at it). + */ + GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE = 1, + + /** + * We should keep track of the route that the message + * took in the P2P network. + */ + GNUNET_DHT_RO_RECORD_ROUTE = 2, + + /** + * This is a 'FIND-PEER' request, so approximate results are fine. + */ + GNUNET_DHT_RO_FIND_PEER = 4, + + /** + * Possible message option for query key randomization. + */ + GNUNET_DHT_RO_BART = 8, + + /** + * Flag given to monitors if this was the last hop for a GET/PUT. + */ + GNUNET_DHT_RO_LAST_HOP = 16 +}; + /** * Initialize the connection with the DHT service. - * + * * @param cfg configuration to use - * @param sched scheduler to use + * @param ht_len size of the internal hash table to use for + * processing multiple GET/FIND requests in parallel * @return NULL on error */ struct GNUNET_DHT_Handle * -GNUNET_DHT_connect (struct GNUNET_SCHEDULER_Handle *sched, - const struct GNUNET_CONFIGURATION_Handle *cfg); +GNUNET_DHT_connect (const struct GNUNET_CONFIGURATION_Handle *cfg, + unsigned int ht_len); /** * Shutdown connection with the DHT service. * - * @param h connection to shut down + * @param handle connection to shut down */ void -GNUNET_DHT_disconnect (struct GNUNET_DHT_Handle *h); +GNUNET_DHT_disconnect (struct GNUNET_DHT_Handle *handle); + + +/* *************** Standard API: get and put ******************* */ /** - * Handle to control a GET operation. + * Opaque handle to cancel a PUT operation. */ -struct GNUNET_DHT_GetHandle; +struct GNUNET_DHT_PutHandle; /** - * Iterator called on each result obtained for a GET - * operation. + * Perform a PUT operation storing data in the DHT. + * + * @param handle handle to DHT service + * @param key the key to store under + * @param desired_replication_level estimate of how many + * nearest peers this request should reach + * @param options routing options for this message + * @param type type of the value + * @param size number of bytes in @a data; must be less than 64k + * @param data the data to store + * @param exp desired expiration time for the value + * @param cont continuation to call when done (transmitting request to service) + * You must not call #GNUNET_DHT_disconnect in this continuation + * @param cont_cls closure for @a cont + * @return handle to cancel the "PUT" operation, NULL on error + * (size too big) + */ +struct GNUNET_DHT_PutHandle * +GNUNET_DHT_put (struct GNUNET_DHT_Handle *handle, + const struct GNUNET_HashCode *key, + uint32_t desired_replication_level, + enum GNUNET_DHT_RouteOption options, + enum GNUNET_BLOCK_Type type, + size_t size, + const void *data, + struct GNUNET_TIME_Absolute exp, + GNUNET_SCHEDULER_TaskCallback cont, + void *cont_cls); + + +/** + * Cancels a DHT PUT operation. Note that the PUT request may still + * go out over the network (we can't stop that); However, if the PUT + * has not yet been sent to the service, cancelling the PUT will stop + * this from happening (but there is no way for the user of this API + * to tell if that is the case). The only use for this API is to + * prevent a later call to 'cont' from #GNUNET_DHT_put (i.e. because + * the system is shutting down). + * + * @param ph put operation to cancel ('cont' will no longer be called) + */ +void +GNUNET_DHT_put_cancel (struct GNUNET_DHT_PutHandle *ph); + + +/** + * Iterator called on each result obtained for a DHT + * operation that expects a reply * * @param cls closure * @param exp when will this value expire * @param key key of the result + * @param get_path peers on reply path (or NULL if not recorded) + * [0] = datastore's first neighbor, [length - 1] = local peer + * @param get_path_length number of entries in @a get_path + * @param put_path peers on the PUT path (or NULL if not recorded) + * [0] = origin, [length - 1] = datastore + * @param put_path_length number of entries in @a put_path * @param type type of the result - * @param size number of bytes in data + * @param size number of bytes in @a data * @param data pointer to the result data */ -typedef void (*GNUNET_DHT_Iterator)(void *cls, - struct GNUNET_TIME_Absolute exp, - const GNUNET_HashCode * key, - uint32_t type, - uint32_t size, - const void *data); - +typedef void +(*GNUNET_DHT_GetIterator) (void *cls, + struct GNUNET_TIME_Absolute exp, + const struct GNUNET_HashCode *key, + const struct GNUNET_PeerIdentity *get_path, + unsigned int get_path_length, + const struct GNUNET_PeerIdentity *put_path, + unsigned int put_path_length, + enum GNUNET_BLOCK_Type type, + size_t size, + const void *data); /** - * Perform an asynchronous GET operation on the DHT identified. + * Perform an asynchronous GET operation on the DHT identified. See + * also #GNUNET_BLOCK_evaluate. * - * @param h handle to the DHT service + * @param handle handle to the DHT service * @param type expected type of the response object * @param key the key to look up + * @param desired_replication_level estimate of how many + nearest peers this request should reach + * @param options routing options for this message + * @param xquery extended query data (can be NULL, depending on type) + * @param xquery_size number of bytes in @a xquery * @param iter function to call on each result - * @param iter_cls closure for iter + * @param iter_cls closure for @a iter * @return handle to stop the async get */ struct GNUNET_DHT_GetHandle * -GNUNET_DHT_get_start (struct GNUNET_DHT_Handle *h, - uint32_t type, - const GNUNET_HashCode * key, - GNUNET_DHT_Iterator iter, - void *iter_cls); +GNUNET_DHT_get_start (struct GNUNET_DHT_Handle *handle, + enum GNUNET_BLOCK_Type type, + const struct GNUNET_HashCode *key, + uint32_t desired_replication_level, + enum GNUNET_DHT_RouteOption options, + const void *xquery, + size_t xquery_size, + GNUNET_DHT_GetIterator iter, + void *iter_cls); /** - * Iterator called on each result obtained from a FIND_PEER - * operation + * Tell the DHT not to return any of the following known results + * to this client. * - * @param cls closure - * @param key the key that was searched - * @param data the HELLO of the peer that was returned + * @param get_handle get operation for which results should be filtered + * @param num_results number of results to be blocked that are + * provided in this call (size of the @a results array) + * @param results array of hash codes over the `data` of the results + * to be blocked */ -typedef void (*GNUNET_DHT_PeerIterator)(void *cls, - const GNUNET_HashCode * key, - const void *data); +void +GNUNET_DHT_get_filter_known_results (struct GNUNET_DHT_GetHandle *get_handle, + unsigned int num_results, + const struct GNUNET_HashCode *results); /** - * Perform an asynchronous FIND_PEER operation on the DHT. + * Stop async DHT-get. Frees associated resources. * - * @param h handle to the DHT service - * @param key the key to look up - * @param iter function to call on each result - * @param iter_cls closure for iter + * @param get_handle GET operation to stop. + */ +void +GNUNET_DHT_get_stop (struct GNUNET_DHT_GetHandle *get_handle); + + +/* *************** Extended API: monitor ******************* */ + +/** + * Handle to monitor requests + */ +struct GNUNET_DHT_MonitorHandle; + +/** + * Callback called on each GET request going through the DHT. * - * @return handle to stop the request + * @param cls Closure. + * @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 @a 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. */ -struct GNUNET_DHT_GetHandle * -GNUNET_DHT_find_peer_start (struct GNUNET_DHT_Handle *h, - const GNUNET_HashCode * key, - GNUNET_DHT_PeerIterator iter, - void *iter_cls); +typedef void +(*GNUNET_DHT_MonitorGetCB) (void *cls, + enum GNUNET_DHT_RouteOption 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); + /** - * Stop async DHT-get. Frees associated resources. + * Callback called on each GET reply going through the DHT. * - * @param record GET operation to stop. + * @param cls Closure. + * @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 @a get_path. + * @param put_path peers on the PUT path (or NULL if not recorded). + * @param put_path_length number of entries in @a 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 -GNUNET_DHT_get_stop (struct GNUNET_DHT_Handle *handle, struct GNUNET_DHT_GetHandle *get_handle); +typedef void +(*GNUNET_DHT_MonitorGetRespCB) (void *cls, + 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); /** - * Perform a PUT operation on the DHT identified by 'table' storing - * a binding of 'key' to 'value'. The peer does not have to be part - * of the table (if so, we will attempt to locate a peer that is!) + * Callback called on each PUT request going through the DHT. * - * @param h handle to DHT service - * @param key the key to store under - * @param type type of the value - * @param size number of bytes in data; must be less than 64k - * @param data the data to store - * @param exp desired expiration time for the value - * @param cont continuation to call when done; - * reason will be TIMEOUT on error, - * reason will be PREREQ_DONE on success - * @param cont_cls closure for cont - * - */ -int GNUNET_DHT_put (struct GNUNET_DHT_Handle *h, - const GNUNET_HashCode * key, - uint32_t type, - uint32_t size, - const char *data, - struct GNUNET_TIME_Relative exp, - GNUNET_SCHEDULER_Task cont, - void *cont_cls); + * @param cls Closure. + * @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 @a 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 @a data. + */ +typedef void +(*GNUNET_DHT_MonitorPutCB) (void *cls, + enum GNUNET_DHT_RouteOption 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); + + + +/** + * Start monitoring the local DHT service. + * + * @param handle Handle to the DHT service. + * @param type Type of blocks that are of interest. + * @param key Key of data of interest, NULL for all. + * @param get_cb Callback to process monitored get messages. + * @param get_resp_cb Callback to process monitored get response messages. + * @param put_cb Callback to process monitored put messages. + * @param cb_cls Closure for callbacks + * @return Handle to stop monitoring. + */ +struct GNUNET_DHT_MonitorHandle * +GNUNET_DHT_monitor_start (struct GNUNET_DHT_Handle *handle, + enum GNUNET_BLOCK_Type type, + const struct GNUNET_HashCode *key, + GNUNET_DHT_MonitorGetCB get_cb, + GNUNET_DHT_MonitorGetRespCB get_resp_cb, + GNUNET_DHT_MonitorPutCB put_cb, + void *cb_cls); + + +/** + * Stop monitoring. + * On return handle will no longer be valid, caller must not use it anymore. + * + * @param handle The handle to the monitor request returned by + * #GNUNET_DHT_monitor_start(). + */ +void +GNUNET_DHT_monitor_stop (struct GNUNET_DHT_MonitorHandle *handle); #if 0 /* keep Emacsens' auto-indent happy */ @@ -180,6 +396,6 @@ int GNUNET_DHT_put (struct GNUNET_DHT_Handle *h, } #endif +#endif -#endif -/* gnunet_dht_service.h */ +/** @} */ /* end of group dht */