diff options
Diffstat (limited to 'src/dht/plugin_block_dht.c')
| -rw-r--r-- | src/dht/plugin_block_dht.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/src/dht/plugin_block_dht.c b/src/dht/plugin_block_dht.c new file mode 100644 index 0000000..19467b9 --- /dev/null +++ b/src/dht/plugin_block_dht.c @@ -0,0 +1,181 @@ +/* + This file is part of GNUnet + (C) 2010 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/plugin_block_dht.c + * @brief block plugin for DHT internals (right now, find-peer requests only); + * other plugins should be used to store "useful" data in the + * DHT (see fs block plugin) + * @author Christian Grothoff + */ + +#include "platform.h" +#include "gnunet_constants.h" +#include "gnunet_hello_lib.h" +#include "gnunet_block_plugin.h" + +#define DEBUG_DHT GNUNET_EXTRA_LOGGING + + +/** + * Function called to validate a reply or a request. For + * request evaluation, simply pass "NULL" for the reply_block. + * + * @param cls closure + * @param type block type + * @param query original query (hash) + * @param bf pointer to bloom filter associated with query; possibly updated (!) + * @param bf_mutator mutation value for bf + * @param xquery extended query data (can be NULL, depending on type) + * @param xquery_size number of bytes in xquery + * @param reply_block response to validate + * @param reply_block_size number of bytes in reply block + * @return characterization of result + */ +static enum GNUNET_BLOCK_EvaluationResult +block_plugin_dht_evaluate (void *cls, enum GNUNET_BLOCK_Type type, + const GNUNET_HashCode * query, + struct GNUNET_CONTAINER_BloomFilter **bf, + int32_t bf_mutator, const void *xquery, + size_t xquery_size, const void *reply_block, + size_t reply_block_size) +{ + GNUNET_HashCode mhash; + const struct GNUNET_HELLO_Message *hello; + struct GNUNET_PeerIdentity pid; + const struct GNUNET_MessageHeader *msg; + + if (type != GNUNET_BLOCK_TYPE_DHT_HELLO) + return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED; + if (xquery_size != 0) + return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID; + if (reply_block_size == 0) + return GNUNET_BLOCK_EVALUATION_REQUEST_VALID; + if (reply_block_size < sizeof (struct GNUNET_MessageHeader)) + return GNUNET_BLOCK_EVALUATION_RESULT_INVALID; + msg = reply_block; + if (reply_block_size != ntohs (msg->size)) + return GNUNET_BLOCK_EVALUATION_RESULT_INVALID; + hello = reply_block; + if (GNUNET_OK != GNUNET_HELLO_get_id (hello, &pid)) + return GNUNET_BLOCK_EVALUATION_RESULT_INVALID; + if (NULL != bf) + { + GNUNET_BLOCK_mingle_hash (&pid.hashPubKey, bf_mutator, &mhash); + if (NULL != *bf) + { + if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (*bf, &mhash)) + return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE; + } + else + { + *bf = + GNUNET_CONTAINER_bloomfilter_init (NULL, 8, + GNUNET_CONSTANTS_BLOOMFILTER_K); + } + GNUNET_CONTAINER_bloomfilter_add (*bf, &mhash); + } + return GNUNET_BLOCK_EVALUATION_OK_MORE; +} + + +/** + * Function called to obtain the key for a block. + * + * @param cls closure + * @param type block type + * @param block block to get the key for + * @param block_size number of bytes in block + * @param key set to the key (query) for the given block + * @return GNUNET_OK on success, GNUNET_SYSERR if type not supported + * (or if extracting a key from a block of this type does not work) + */ +static int +block_plugin_dht_get_key (void *cls, enum GNUNET_BLOCK_Type type, + const void *block, size_t block_size, + GNUNET_HashCode * key) +{ + const struct GNUNET_MessageHeader *msg; + const struct GNUNET_HELLO_Message *hello; + struct GNUNET_PeerIdentity *pid; + + if (type != GNUNET_BLOCK_TYPE_DHT_HELLO) + return GNUNET_SYSERR; + if (block_size < sizeof (struct GNUNET_MessageHeader)) + { + GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR, "block-dht", + _("Block not of type %u\n"), GNUNET_BLOCK_TYPE_DHT_HELLO); + return GNUNET_NO; + } + msg = block; + if (block_size != ntohs (msg->size)) + { + GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR, "block-dht", + _("Size mismatch for block\n"), + GNUNET_BLOCK_TYPE_DHT_HELLO); + return GNUNET_NO; + } + hello = block; + pid = (struct GNUNET_PeerIdentity *) key; + if (GNUNET_OK != GNUNET_HELLO_get_id (hello, pid)) + { + GNUNET_log_from (GNUNET_ERROR_TYPE_ERROR, "block-dht", + _("Block of type %u is malformed\n"), + GNUNET_BLOCK_TYPE_DHT_HELLO); + return GNUNET_NO; + } + return GNUNET_OK; +} + + +/** + * Entry point for the plugin. + */ +void * +libgnunet_plugin_block_dht_init (void *cls) +{ + static enum GNUNET_BLOCK_Type types[] = + { + GNUNET_BLOCK_TYPE_DHT_HELLO, + GNUNET_BLOCK_TYPE_ANY /* end of list */ + }; + struct GNUNET_BLOCK_PluginFunctions *api; + + api = GNUNET_malloc (sizeof (struct GNUNET_BLOCK_PluginFunctions)); + api->evaluate = &block_plugin_dht_evaluate; + api->get_key = &block_plugin_dht_get_key; + api->types = types; + return api; +} + + +/** + * Exit point from the plugin. + */ +void * +libgnunet_plugin_block_dht_done (void *cls) +{ + struct GNUNET_TRANSPORT_PluginFunctions *api = cls; + + GNUNET_free (api); + return NULL; +} + +/* end of plugin_block_dht.c */ |