/* This file is part of GNUnet. (C) 2009, 2010, 2011 Christian Grothoff (and other contributing authors) 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 3, 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. 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. */ /** * @file dht/gnunet-service-dht_datacache.c * @brief GNUnet DHT service's datacache integration * @author Christian Grothoff * @author Nathan Evans */ #include "platform.h" #include "gnunet_datacache_lib.h" #include "gnunet-service-dht_clients.h" #include "gnunet-service-dht_datacache.h" #include "gnunet-service-dht_routing.h" #include "gnunet-service-dht.h" /** * Handle to the datacache service (for inserting/retrieving data) */ static struct GNUNET_DATACACHE_Handle *datacache; /** * Entry for inserting data into datacache from the DHT. */ struct DHTPutEntry { /** * Size of data. */ uint16_t data_size; /** * Length of recorded path. */ uint16_t path_length; /* PATH ENTRIES */ /* PUT DATA */ }; /** * Handle a datum we've received from another peer. Cache if * possible. * * @param expiration when will the reply expire * @param key the query this reply is for * @param put_path_length number of peers in 'put_path' * @param put_path path the reply took on put * @param type type of the reply * @param data_size number of bytes in 'data' * @param data application payload data */ void GDS_DATACACHE_handle_put (struct GNUNET_TIME_Absolute expiration, const GNUNET_HashCode * key, unsigned int put_path_length, const struct GNUNET_PeerIdentity *put_path, enum GNUNET_BLOCK_Type type, size_t data_size, const void *data) { size_t plen = data_size + put_path_length * sizeof (struct GNUNET_PeerIdentity) + sizeof (struct DHTPutEntry); char buf[plen]; struct DHTPutEntry *pe; struct GNUNET_PeerIdentity *pp; if (datacache == NULL) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("%s request received, but have no datacache!\n"), "PUT"); return; } if (data_size >= GNUNET_SERVER_MAX_MESSAGE_SIZE) { GNUNET_break (0); return; } /* Put size is actual data size plus struct overhead plus path length (if any) */ GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# ITEMS stored in datacache"), 1, GNUNET_NO); pe = (struct DHTPutEntry *) buf; pe->data_size = htons (data_size); pe->path_length = htons ((uint16_t) put_path_length); pp = (struct GNUNET_PeerIdentity *) &pe[1]; memcpy (pp, put_path, put_path_length * sizeof (struct GNUNET_PeerIdentity)); memcpy (&pp[put_path_length], data, data_size); (void) GNUNET_DATACACHE_put (datacache, key, plen, (const char *) pe, type, expiration); } /** * Context containing information about a GET request. */ struct GetRequestContext { /** * extended query (see gnunet_block_lib.h). */ const void *xquery; /** * Bloomfilter to filter out duplicate replies (updated) */ struct GNUNET_CONTAINER_BloomFilter **reply_bf; /** * The key this request was about */ GNUNET_HashCode key; /** * Number of bytes in xquery. */ size_t xquery_size; /** * Mutator value for the reply_bf, see gnunet_block_lib.h */ uint32_t reply_bf_mutator; /** * Return value to give back. */ enum GNUNET_BLOCK_EvaluationResult eval; }; /** * Iterator for local get request results, * * @param cls closure for iterator, a DatacacheGetContext * @param exp when does this value expire? * @param key the key this data is stored under * @param size the size of the data identified by key * @param data the actual data * @param type the type of the data * * @return GNUNET_OK to continue iteration, anything else * to stop iteration. */ static int datacache_get_iterator (void *cls, struct GNUNET_TIME_Absolute exp, const GNUNET_HashCode * key, size_t size, const char *data, enum GNUNET_BLOCK_Type type) { struct GetRequestContext *ctx = cls; const struct DHTPutEntry *pe; const struct GNUNET_PeerIdentity *pp; const char *rdata; size_t rdata_size; uint16_t put_path_length; enum GNUNET_BLOCK_EvaluationResult eval; pe = (const struct DHTPutEntry *) data; put_path_length = ntohs (pe->path_length); rdata_size = ntohs (pe->data_size); if (size != sizeof (struct DHTPutEntry) + rdata_size + (put_path_length * sizeof (struct GNUNET_PeerIdentity))) { GNUNET_break (0); return GNUNET_OK; } pp = (const struct GNUNET_PeerIdentity *) &pe[1]; rdata = (const char *) &pp[put_path_length]; eval = GNUNET_BLOCK_evaluate (GDS_block_context, type, key, ctx->reply_bf, ctx->reply_bf_mutator, ctx->xquery, ctx->xquery_size, rdata, rdata_size); #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Found reply for query %s in datacache, evaluation result is %d\n", GNUNET_h2s (key), (int) eval); #endif ctx->eval = eval; switch (eval) { case GNUNET_BLOCK_EVALUATION_OK_LAST: case GNUNET_BLOCK_EVALUATION_OK_MORE: /* forward to local clients */ GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# Good RESULTS found in datacache"), 1, GNUNET_NO); GDS_CLIENTS_handle_reply (exp, key, 0, NULL, put_path_length, pp, type, rdata_size, rdata); /* forward to other peers */ GDS_ROUTING_process (type, exp, key, put_path_length, pp, 0, NULL, rdata, rdata_size); break; case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE: GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# Duplicate RESULTS found in datacache"), 1, GNUNET_NO); break; case GNUNET_BLOCK_EVALUATION_RESULT_INVALID: GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# Invalid RESULTS found in datacache"), 1, GNUNET_NO); break; case GNUNET_BLOCK_EVALUATION_REQUEST_VALID: GNUNET_break (0); break; case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID: GNUNET_break_op (0); return GNUNET_SYSERR; case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED: GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# Unsupported RESULTS found in datacache"), 1, GNUNET_NO); GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("Unsupported block type (%u) in local response!\n"), type); break; } return (eval == GNUNET_BLOCK_EVALUATION_OK_LAST) ? GNUNET_NO : GNUNET_OK; } /** * Handle a GET request we've received from another peer. * * @param key the query * @param type requested data type * @param xquery extended query * @param xquery_size number of bytes in xquery * @param reply_bf where the reply bf is (to be) stored, possibly updated, can be NULL * @param reply_bf_mutator mutation value for reply_bf * @return evaluation result for the local replies */ enum GNUNET_BLOCK_EvaluationResult GDS_DATACACHE_handle_get (const GNUNET_HashCode * key, enum GNUNET_BLOCK_Type type, const void *xquery, size_t xquery_size, struct GNUNET_CONTAINER_BloomFilter **reply_bf, uint32_t reply_bf_mutator) { struct GetRequestContext ctx; if (datacache == NULL) return GNUNET_BLOCK_EVALUATION_REQUEST_VALID; GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# GET requests given to datacache"), 1, GNUNET_NO); ctx.eval = GNUNET_BLOCK_EVALUATION_REQUEST_VALID; ctx.key = *key; ctx.xquery = xquery; ctx.xquery_size = xquery_size; ctx.reply_bf = reply_bf; ctx.reply_bf_mutator = reply_bf_mutator; (void) GNUNET_DATACACHE_get (datacache, key, type, &datacache_get_iterator, &ctx); return ctx.eval; } /** * Initialize datacache subsystem. */ void GDS_DATACACHE_init () { datacache = GNUNET_DATACACHE_create (GDS_cfg, "dhtcache"); } /** * Shutdown datacache subsystem. */ void GDS_DATACACHE_done () { if (datacache != NULL) { GNUNET_DATACACHE_destroy (datacache); datacache = NULL; } } /* end of gnunet-service-dht_datacache.c */