/* 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 gns/plugin_block_gns.c * @brief blocks used for GNS records * @author Martin Schanzenbach */ #include "platform.h" #include "gnunet_block_plugin.h" #include "gnunet_namestore_service.h" #include "block_gns.h" #include "gnunet_signatures.h" /** * Number of bits we set per entry in the bloomfilter. * Do not change! -from fs */ #define BLOOMFILTER_K 16 /** * Function called to validate a reply or a request. For * request evaluation, simply pass "NULL" for the reply_block. * Note that it is assumed that the reply has already been * matched to the key (and signatures checked) as it would * be done with the "get_key" function. * * @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 extrended 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_gns_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) { if (type != GNUNET_BLOCK_TYPE_GNS_NAMERECORD) return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED; if (reply_block_size == 0) return GNUNET_BLOCK_EVALUATION_REQUEST_VALID; char* name; GNUNET_HashCode pkey_hash; GNUNET_HashCode query_key; GNUNET_HashCode name_hash; GNUNET_HashCode mhash; GNUNET_HashCode chash; struct GNSNameRecordBlock *nrb; struct GNSRecordBlock *rb; uint32_t rd_count; nrb = (struct GNSNameRecordBlock *)reply_block; name = (char*)&nrb[1]; GNUNET_CRYPTO_hash(&nrb->public_key, sizeof(nrb->public_key), &pkey_hash); GNUNET_CRYPTO_hash(name, strlen(name), &name_hash); GNUNET_CRYPTO_hash_xor(&pkey_hash, &name_hash, &query_key); /* Check query key against public key */ if (0 != GNUNET_CRYPTO_hash_cmp(query, &query_key)) return GNUNET_BLOCK_EVALUATION_REQUEST_VALID; rd_count = ntohl(nrb->rd_count); struct GNUNET_NAMESTORE_RecordData rd[rd_count]; int i = 0; int record_match = 0; uint32_t record_xquery = ntohl(*((uint32_t*)xquery)); rb = (struct GNSRecordBlock*)(&name[strlen(name) + 1]); for (i=0; itype); rd[i].expiration = GNUNET_TIME_absolute_ntoh(rb->expiration); rd[i].data_size = ntohl(rb->data_length); rd[i].flags = ntohl(rb->flags); rd[i].data = (char*)&rb[1]; rb = (struct GNSRecordBlock *)((char*)&rb[1] + rd[i].data_size); if (xquery_size == 0) continue; if (rd[i].record_type == record_xquery) { record_match++; } } /*if (GNUNET_OK != GNUNET_NAMESTORE_verify_signature (&nrb->public_key, name, rd_count, rd, NULL)) { GNUNET_log(GNUNET_ERROR_TYPE_INFO, "Signature invalid\n"); return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID; }*/ //No record matches query if ((xquery_size > 0) && (record_match == 0)) return GNUNET_BLOCK_EVALUATION_REQUEST_VALID; GNUNET_log(GNUNET_ERROR_TYPE_INFO, "Records match\n"); //FIXME do bf check before or after crypto?? if (NULL != bf) { GNUNET_CRYPTO_hash(reply_block, reply_block_size, &chash); GNUNET_BLOCK_mingle_hash(&chash, bf_mutator, &mhash); if (NULL != *bf) { GNUNET_log(GNUNET_ERROR_TYPE_INFO, "Check BF\n"); if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test(*bf, &mhash)) return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE; } else { *bf = GNUNET_CONTAINER_bloomfilter_init(NULL, 8, BLOOMFILTER_K); } GNUNET_CONTAINER_bloomfilter_add(*bf, &mhash); } GNUNET_log(GNUNET_ERROR_TYPE_INFO, "No dup\n"); 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_gns_get_key (void *cls, enum GNUNET_BLOCK_Type type, const void *block, size_t block_size, GNUNET_HashCode * key) { if (type != GNUNET_BLOCK_TYPE_GNS_NAMERECORD) return GNUNET_SYSERR; GNUNET_HashCode name_hash; GNUNET_HashCode pkey_hash; struct GNSNameRecordBlock *nrb = (struct GNSNameRecordBlock *)block; GNUNET_CRYPTO_hash(&nrb[1], strlen((char*)&nrb[1]), &name_hash); GNUNET_CRYPTO_hash(&nrb->public_key, sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded), &pkey_hash); GNUNET_CRYPTO_hash_xor(&name_hash, &pkey_hash, key); //FIXME calculate key from name and hash(pkey) here return GNUNET_OK; } /** * Entry point for the plugin. */ void * libgnunet_plugin_block_gns_init (void *cls) { static enum GNUNET_BLOCK_Type types[] = { GNUNET_BLOCK_TYPE_GNS_NAMERECORD, GNUNET_BLOCK_TYPE_ANY /* end of list */ }; struct GNUNET_BLOCK_PluginFunctions *api; api = GNUNET_malloc (sizeof (struct GNUNET_BLOCK_PluginFunctions)); api->evaluate = &block_plugin_gns_evaluate; api->get_key = &block_plugin_gns_get_key; api->types = types; return api; } /** * Exit point from the plugin. */ void * libgnunet_plugin_block_gns_done (void *cls) { struct GNUNET_TRANSPORT_PluginFunctions *api = cls; GNUNET_free (api); return NULL; } /* end of plugin_block_gns.c */