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 struct 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 struct GNUNET_HashCode pkey_hash_double;
67 struct GNUNET_HashCode query_key;
68 struct GNUNET_HashCode name_hash_double;
69 struct GNUNET_HashCode mhash;
70 struct 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))
93 return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
95 return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
100 nrb = (struct GNSNameRecordBlock *)reply_block;
101 name = (char*)&nrb[1];
102 GNUNET_CRYPTO_short_hash(&nrb->public_key,
103 sizeof(nrb->public_key),
106 GNUNET_CRYPTO_short_hash(name, strlen(name), &name_hash);
108 GNUNET_CRYPTO_short_hash_double(&name_hash, &name_hash_double);
109 GNUNET_CRYPTO_short_hash_double(&pkey_hash, &pkey_hash_double);
111 GNUNET_CRYPTO_hash_xor(&pkey_hash_double, &name_hash_double, &query_key);
113 struct GNUNET_CRYPTO_HashAsciiEncoded xor_exp;
114 struct GNUNET_CRYPTO_HashAsciiEncoded xor_got;
115 GNUNET_CRYPTO_hash_to_enc (&query_key, &xor_exp);
116 GNUNET_CRYPTO_hash_to_enc (query, &xor_got);
118 //GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
119 // "BLOCK_TEST for %s got %s expected %s\n",
120 // name, (char*) &xor_got, (char*) &xor_exp);
122 /* Check query key against public key */
123 if (0 != GNUNET_CRYPTO_hash_cmp(query, &query_key))
126 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
130 rd_count = ntohl(nrb->rd_count);
131 rd_data = (char*)&nrb[1];
132 rd_data += strlen(name) + 1;
133 rd_len = reply_block_size - (strlen(name) + 1
134 + sizeof(struct GNSNameRecordBlock));
136 struct GNUNET_NAMESTORE_RecordData rd[rd_count];
138 uint64_t exp = UINT64_MAX;
139 struct GNUNET_TIME_Absolute et = GNUNET_TIME_UNIT_FOREVER_ABS;
141 if (GNUNET_SYSERR == GNUNET_NAMESTORE_records_deserialize (rd_len,
146 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
147 "Data invalid (%d bytes, %d records)\n", rd_len, rd_count);
148 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
151 if (xquery_size < sizeof(uint32_t))
154 record_xquery = ntohl(*((uint32_t*)xquery));
156 for (i=0; i<rd_count; i++)
158 GNUNET_break (0 == (rd[i].flags & GNUNET_NAMESTORE_RF_RELATIVE_EXPIRATION));
159 exp = GNUNET_MIN (exp, rd[i].expiration_time);
160 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
161 "Got record of size %d expiration %u\n",
162 rd[i].data_size, rd[i].expiration_time);
163 if ((record_xquery != 0)
164 && (rd[i].record_type == record_xquery))
171 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
172 "Verifying signature of %d records for name %s with expiration of %u\n",
173 rd_count, name, et.abs_value);
175 if (GNUNET_OK != GNUNET_NAMESTORE_verify_signature (&nrb->public_key,
182 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Signature invalid for %s\n", name);
184 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
190 GNUNET_CRYPTO_hash(reply_block, reply_block_size, &chash);
191 GNUNET_BLOCK_mingle_hash(&chash, bf_mutator, &mhash);
194 if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test(*bf, &mhash))
195 return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
199 *bf = GNUNET_CONTAINER_bloomfilter_init(NULL, 8, BLOOMFILTER_K);
201 GNUNET_CONTAINER_bloomfilter_add(*bf, &mhash);
203 return GNUNET_BLOCK_EVALUATION_OK_MORE;
208 * Function called to obtain the key for a block.
211 * @param type block type
212 * @param block block to get the key for
213 * @param block_size number of bytes in block
214 * @param key set to the key (query) for the given block
215 * @return GNUNET_OK on success, GNUNET_SYSERR if type not supported
216 * (or if extracting a key from a block of this type does not work)
219 block_plugin_gns_get_key (void *cls, enum GNUNET_BLOCK_Type type,
220 const void *block, size_t block_size,
221 struct GNUNET_HashCode * key)
223 if (type != GNUNET_BLOCK_TYPE_GNS_NAMERECORD)
224 return GNUNET_SYSERR;
225 struct GNUNET_CRYPTO_ShortHashCode name_hash;
226 struct GNUNET_CRYPTO_ShortHashCode pkey_hash;
227 struct GNUNET_HashCode name_hash_double;
228 struct GNUNET_HashCode pkey_hash_double;
230 struct GNSNameRecordBlock *nrb = (struct GNSNameRecordBlock *)block;
232 GNUNET_CRYPTO_short_hash(&nrb[1], strlen((char*)&nrb[1]), &name_hash);
233 GNUNET_CRYPTO_short_hash(&nrb->public_key,
234 sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
237 GNUNET_CRYPTO_short_hash_double(&name_hash, &name_hash_double);
238 GNUNET_CRYPTO_short_hash_double(&pkey_hash, &pkey_hash_double);
240 GNUNET_CRYPTO_hash_xor(&name_hash_double, &pkey_hash_double, key);
247 * Entry point for the plugin.
250 libgnunet_plugin_block_gns_init (void *cls)
252 static enum GNUNET_BLOCK_Type types[] =
254 GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
255 GNUNET_BLOCK_TYPE_ANY /* end of list */
257 struct GNUNET_BLOCK_PluginFunctions *api;
259 api = GNUNET_malloc (sizeof (struct GNUNET_BLOCK_PluginFunctions));
260 api->evaluate = &block_plugin_gns_evaluate;
261 api->get_key = &block_plugin_gns_get_key;
268 * Exit point from the plugin.
271 libgnunet_plugin_block_gns_done (void *cls)
273 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
279 /* end of plugin_block_gns.c */