2 This file is part of GNUnet
3 Copyright (C) 2010-2013 GNUnet e.V.
5 GNUnet is free software: you can redistribute it and/or modify it
6 under the terms of the GNU Affero General Public License as published
7 by the Free Software Foundation, either version 3 of the License,
8 or (at your 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 Affero General Public License for more details.
15 You should have received a copy of the GNU Affero General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
18 SPDX-License-Identifier: AGPL3.0-or-later
22 * @file gns/plugin_block_gns.c
23 * @brief blocks used for GNS records
24 * @author Martin Schanzenbach
25 * @author Christian Grothoff
29 #include "gnunet_block_group_lib.h"
30 #include "gnunet_block_plugin.h"
31 #include "gnunet_namestore_service.h"
32 #include "gnunet_signatures.h"
35 * Number of bits we set per entry in the bloomfilter.
36 * Do not change! -from fs
38 #define BLOOMFILTER_K 16
41 * How big is the BF we use for GNS blocks?
47 * Create a new block group.
49 * @param ctx block context in which the block group is created
50 * @param type type of the block for which we are creating the group
51 * @param nonce random value used to seed the group creation
52 * @param raw_data optional serialized prior state of the group, NULL if unavailable/fresh
53 * @param raw_data_size number of bytes in @a raw_data, 0 if unavailable/fresh
54 * @param va variable arguments specific to @a type
55 * @return block group handle, NULL if block groups are not supported
56 * by this @a type of block (this is not an error)
58 static struct GNUNET_BLOCK_Group *
59 block_plugin_gns_create_group (void *cls,
60 enum GNUNET_BLOCK_Type type,
69 guard = va_arg (va, const char *);
70 if (0 == strcmp (guard,
72 bf_size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size (va_arg (va, unsigned int),
74 else if (0 == strcmp (guard,
76 bf_size = va_arg (va, unsigned int);
80 bf_size = GNS_BF_SIZE;
82 GNUNET_break (NULL == va_arg (va, const char *));
83 return GNUNET_BLOCK_GROUP_bf_create (cls,
94 * Function called to validate a reply or a request. For
95 * request evaluation, simply pass "NULL" for the reply_block.
96 * Note that it is assumed that the reply has already been
97 * matched to the key (and signatures checked) as it would
98 * be done with the "get_key" function.
101 * @param ctx block context
102 * @param type block type
103 * @param bg block group to use for evaluation
104 * @param eo control flags
105 * @param query original query (hash)
106 * @param xquery extrended query data (can be NULL, depending on @a type)
107 * @param xquery_size number of bytes in @a xquery
108 * @param reply_block response to validate
109 * @param reply_block_size number of bytes in @a reply_block
110 * @return characterization of result
112 static enum GNUNET_BLOCK_EvaluationResult
113 block_plugin_gns_evaluate (void *cls,
114 struct GNUNET_BLOCK_Context *ctx,
115 enum GNUNET_BLOCK_Type type,
116 struct GNUNET_BLOCK_Group *bg,
117 enum GNUNET_BLOCK_EvaluationOptions eo,
118 const struct GNUNET_HashCode *query,
121 const void *reply_block,
122 size_t reply_block_size)
124 const struct GNUNET_GNSRECORD_Block *block;
125 struct GNUNET_HashCode h;
126 struct GNUNET_HashCode chash;
128 if (type != GNUNET_BLOCK_TYPE_GNS_NAMERECORD)
129 return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
130 if (NULL == reply_block)
132 if (0 != xquery_size)
135 return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
137 return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
140 /* this is a reply */
141 if (reply_block_size < sizeof (struct GNUNET_GNSRECORD_Block))
144 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
147 if (ntohl (block->purpose.size) + sizeof (struct GNUNET_CRYPTO_EcdsaSignature) + sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey) !=
151 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
153 GNUNET_CRYPTO_hash (&block->derived_key,
154 sizeof (block->derived_key),
156 if (0 != GNUNET_memcmp (&h, query))
159 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
162 GNUNET_GNSRECORD_block_verify (block))
165 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
167 GNUNET_CRYPTO_hash (reply_block,
171 GNUNET_BLOCK_GROUP_bf_test_and_set (bg,
173 return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
174 return GNUNET_BLOCK_EVALUATION_OK_MORE;
179 * Function called to obtain the key for a block.
182 * @param type block type
183 * @param reply_block block to get the key for
184 * @param reply_block_size number of bytes in @a reply_block
185 * @param key set to the key (query) for the given block
186 * @return #GNUNET_OK on success, #GNUNET_SYSERR if type not supported
187 * (or if extracting a key from a block of this type does not work)
190 block_plugin_gns_get_key (void *cls,
191 enum GNUNET_BLOCK_Type type,
192 const void *reply_block,
193 size_t reply_block_size,
194 struct GNUNET_HashCode *key)
196 const struct GNUNET_GNSRECORD_Block *block;
198 if (type != GNUNET_BLOCK_TYPE_GNS_NAMERECORD)
199 return GNUNET_SYSERR;
200 if (reply_block_size < sizeof (struct GNUNET_GNSRECORD_Block))
203 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
206 GNUNET_CRYPTO_hash (&block->derived_key,
207 sizeof (block->derived_key),
214 * Entry point for the plugin.
217 libgnunet_plugin_block_gns_init (void *cls)
219 static enum GNUNET_BLOCK_Type types[] =
221 GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
222 GNUNET_BLOCK_TYPE_ANY /* end of list */
224 struct GNUNET_BLOCK_PluginFunctions *api;
226 api = GNUNET_new (struct GNUNET_BLOCK_PluginFunctions);
227 api->evaluate = &block_plugin_gns_evaluate;
228 api->get_key = &block_plugin_gns_get_key;
229 api->create_group = &block_plugin_gns_create_group;
236 * Exit point from the plugin.
239 libgnunet_plugin_block_gns_done (void *cls)
241 struct GNUNET_BLOCK_PluginFunctions *api = cls;
247 /* end of plugin_block_gns.c */