2 This file is part of GNUnet
3 (C) 2010 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file gns/plugin_block_gns.c
23 * @brief blocks used for GNS records
24 * @author Martin Schanzenbach
28 #include "gnunet_block_plugin.h"
29 #include "gnunet_namestore_service.h"
30 #include "block_gns.h"
31 #include "gnunet_signatures.h"
34 * Number of bits we set per entry in the bloomfilter.
35 * Do not change! -from fs
37 #define BLOOMFILTER_K 16
40 * Function called to validate a reply or a request. For
41 * request evaluation, simply pass "NULL" for the reply_block.
42 * Note that it is assumed that the reply has already been
43 * matched to the key (and signatures checked) as it would
44 * be done with the "get_key" function.
47 * @param type block type
48 * @param query original query (hash)
49 * @param bf pointer to bloom filter associated with query; possibly updated (!)
50 * @param bf_mutator mutation value for bf
51 * @param xquery extrended query data (can be NULL, depending on type)
52 * @param xquery_size number of bytes in xquery
53 * @param reply_block response to validate
54 * @param reply_block_size number of bytes in reply block
55 * @return characterization of result
57 static enum GNUNET_BLOCK_EvaluationResult
58 block_plugin_gns_evaluate (void *cls, enum GNUNET_BLOCK_Type type,
59 const GNUNET_HashCode * query,
60 struct GNUNET_CONTAINER_BloomFilter **bf,
61 int32_t bf_mutator, const void *xquery,
62 size_t xquery_size, const void *reply_block,
63 size_t reply_block_size)
66 GNUNET_HashCode pkey_hash_double;
67 GNUNET_HashCode query_key;
68 GNUNET_HashCode name_hash_double;
69 GNUNET_HashCode mhash;
70 GNUNET_HashCode chash;
71 struct GNUNET_CRYPTO_ShortHashCode pkey_hash;
72 struct GNUNET_CRYPTO_ShortHashCode name_hash;
73 struct GNSNameRecordBlock *nrb;
77 uint32_t record_xquery;
78 unsigned int record_match;
80 //GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "RB SIZE %d\n", reply_block_size);
82 if (type != GNUNET_BLOCK_TYPE_GNS_NAMERECORD)
83 return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
84 if (reply_block == NULL)
87 * check if request is valid
88 * FIXME we could check for the record types here
90 if (xquery_size < sizeof(uint32_t))
91 return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
93 return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
98 nrb = (struct GNSNameRecordBlock *)reply_block;
99 name = (char*)&nrb[1];
100 GNUNET_CRYPTO_short_hash(&nrb->public_key,
101 sizeof(nrb->public_key),
104 GNUNET_CRYPTO_short_hash(name, strlen(name), &name_hash);
106 GNUNET_CRYPTO_short_hash_double(&name_hash, &name_hash_double);
107 GNUNET_CRYPTO_short_hash_double(&pkey_hash, &pkey_hash_double);
109 GNUNET_CRYPTO_hash_xor(&pkey_hash_double, &name_hash_double, &query_key);
111 struct GNUNET_CRYPTO_HashAsciiEncoded xor_exp;
112 struct GNUNET_CRYPTO_HashAsciiEncoded xor_got;
113 GNUNET_CRYPTO_hash_to_enc (&query_key, &xor_exp);
114 GNUNET_CRYPTO_hash_to_enc (query, &xor_got);
116 //GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
117 // "BLOCK_TEST for %s got %s expected %s\n",
118 // name, (char*) &xor_got, (char*) &xor_exp);
120 /* Check query key against public key */
121 if (0 != GNUNET_CRYPTO_hash_cmp(query, &query_key))
122 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
125 rd_count = ntohl(nrb->rd_count);
126 rd_data = (char*)&nrb[1];
127 rd_data += strlen(name) + 1;
128 rd_len = reply_block_size - (strlen(name) + 1
129 + sizeof(struct GNSNameRecordBlock));
131 struct GNUNET_NAMESTORE_RecordData rd[rd_count];
133 struct GNUNET_TIME_Absolute exp = GNUNET_TIME_absolute_get_forever();
135 if (GNUNET_SYSERR == GNUNET_NAMESTORE_records_deserialize (rd_len,
140 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
141 "Data invalid (%d bytes, %d records)\n", rd_len, rd_count);
142 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
145 if (xquery_size < sizeof(uint32_t))
148 record_xquery = ntohl(*((uint32_t*)xquery));
150 for (i=0; i<rd_count; i++)
153 exp = GNUNET_TIME_absolute_min (exp, rd[i].expiration);
155 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
156 "Got record of size %d\n", rd[i].data_size);
158 if ((record_xquery != 0)
159 && (rd[i].record_type == record_xquery))
165 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
166 "Verifying signature of %d records for name %s\n",
169 if (GNUNET_OK != GNUNET_NAMESTORE_verify_signature (&nrb->public_key,
176 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Signature invalid for name %s\n");
177 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
183 GNUNET_CRYPTO_hash(reply_block, reply_block_size, &chash);
184 GNUNET_BLOCK_mingle_hash(&chash, bf_mutator, &mhash);
187 if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test(*bf, &mhash))
188 return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
192 *bf = GNUNET_CONTAINER_bloomfilter_init(NULL, 8, BLOOMFILTER_K);
194 GNUNET_CONTAINER_bloomfilter_add(*bf, &mhash);
196 return GNUNET_BLOCK_EVALUATION_OK_MORE;
201 * Function called to obtain the key for a block.
204 * @param type block type
205 * @param block block to get the key for
206 * @param block_size number of bytes in block
207 * @param key set to the key (query) for the given block
208 * @return GNUNET_OK on success, GNUNET_SYSERR if type not supported
209 * (or if extracting a key from a block of this type does not work)
212 block_plugin_gns_get_key (void *cls, enum GNUNET_BLOCK_Type type,
213 const void *block, size_t block_size,
214 GNUNET_HashCode * key)
216 if (type != GNUNET_BLOCK_TYPE_GNS_NAMERECORD)
217 return GNUNET_SYSERR;
218 struct GNUNET_CRYPTO_ShortHashCode name_hash;
219 struct GNUNET_CRYPTO_ShortHashCode pkey_hash;
220 GNUNET_HashCode name_hash_double;
221 GNUNET_HashCode pkey_hash_double;
223 struct GNSNameRecordBlock *nrb = (struct GNSNameRecordBlock *)block;
225 GNUNET_CRYPTO_short_hash(&nrb[1], strlen((char*)&nrb[1]), &name_hash);
226 GNUNET_CRYPTO_short_hash(&nrb->public_key,
227 sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
230 GNUNET_CRYPTO_short_hash_double(&name_hash, &name_hash_double);
231 GNUNET_CRYPTO_short_hash_double(&pkey_hash, &pkey_hash_double);
233 GNUNET_CRYPTO_hash_xor(&name_hash_double, &pkey_hash_double, key);
240 * Entry point for the plugin.
243 libgnunet_plugin_block_gns_init (void *cls)
245 static enum GNUNET_BLOCK_Type types[] =
247 GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
248 GNUNET_BLOCK_TYPE_ANY /* end of list */
250 struct GNUNET_BLOCK_PluginFunctions *api;
252 api = GNUNET_malloc (sizeof (struct GNUNET_BLOCK_PluginFunctions));
253 api->evaluate = &block_plugin_gns_evaluate;
254 api->get_key = &block_plugin_gns_get_key;
261 * Exit point from the plugin.
264 libgnunet_plugin_block_gns_done (void *cls)
266 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
272 /* end of plugin_block_gns.c */