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7 by the Free Software Foundation, either version 3 of the License,
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13 Affero General Public License for more details.
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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
75 else if (0 == strcmp (guard,
77 bf_size = va_arg (va, unsigned int);
81 bf_size = GNS_BF_SIZE;
83 GNUNET_break (NULL == va_arg (va, const char *));
84 return GNUNET_BLOCK_GROUP_bf_create (cls,
95 * Function called to validate a reply or a request. For
96 * request evaluation, simply pass "NULL" for the reply_block.
97 * Note that it is assumed that the reply has already been
98 * matched to the key (and signatures checked) as it would
99 * be done with the "get_key" function.
102 * @param ctx block context
103 * @param type block type
104 * @param bg block group to use for evaluation
105 * @param eo control flags
106 * @param query original query (hash)
107 * @param xquery extrended query data (can be NULL, depending on @a type)
108 * @param xquery_size number of bytes in @a xquery
109 * @param reply_block response to validate
110 * @param reply_block_size number of bytes in @a reply_block
111 * @return characterization of result
113 static enum GNUNET_BLOCK_EvaluationResult
114 block_plugin_gns_evaluate (void *cls,
115 struct GNUNET_BLOCK_Context *ctx,
116 enum GNUNET_BLOCK_Type type,
117 struct GNUNET_BLOCK_Group *bg,
118 enum GNUNET_BLOCK_EvaluationOptions eo,
119 const struct GNUNET_HashCode *query,
122 const void *reply_block,
123 size_t reply_block_size)
125 const struct GNUNET_GNSRECORD_Block *block;
126 struct GNUNET_HashCode h;
127 struct GNUNET_HashCode chash;
129 if (type != GNUNET_BLOCK_TYPE_GNS_NAMERECORD)
130 return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
131 if (NULL == reply_block)
133 if (0 != xquery_size)
136 return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
138 return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
141 /* this is a reply */
142 if (reply_block_size < sizeof(struct GNUNET_GNSRECORD_Block))
145 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
148 if (ntohl (block->purpose.size) + sizeof(struct
149 GNUNET_CRYPTO_EcdsaSignature)
150 + sizeof(struct GNUNET_CRYPTO_EcdsaPublicKey) !=
154 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
156 GNUNET_CRYPTO_hash (&block->derived_key,
157 sizeof(block->derived_key),
159 if (0 != GNUNET_memcmp (&h, query))
162 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
165 GNUNET_GNSRECORD_block_verify (block))
168 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
170 GNUNET_CRYPTO_hash (reply_block,
174 GNUNET_BLOCK_GROUP_bf_test_and_set (bg,
176 return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
177 return GNUNET_BLOCK_EVALUATION_OK_MORE;
182 * Function called to obtain the key for a block.
185 * @param type block type
186 * @param reply_block block to get the key for
187 * @param reply_block_size number of bytes in @a reply_block
188 * @param key set to the key (query) for the given block
189 * @return #GNUNET_OK on success, #GNUNET_SYSERR if type not supported
190 * (or if extracting a key from a block of this type does not work)
193 block_plugin_gns_get_key (void *cls,
194 enum GNUNET_BLOCK_Type type,
195 const void *reply_block,
196 size_t reply_block_size,
197 struct GNUNET_HashCode *key)
199 const struct GNUNET_GNSRECORD_Block *block;
201 if (type != GNUNET_BLOCK_TYPE_GNS_NAMERECORD)
202 return GNUNET_SYSERR;
203 if (reply_block_size < sizeof(struct GNUNET_GNSRECORD_Block))
206 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
209 GNUNET_CRYPTO_hash (&block->derived_key,
210 sizeof(block->derived_key),
217 * Entry point for the plugin.
220 libgnunet_plugin_block_gns_init (void *cls)
222 static enum GNUNET_BLOCK_Type types[] = {
223 GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
224 GNUNET_BLOCK_TYPE_ANY /* end of list */
226 struct GNUNET_BLOCK_PluginFunctions *api;
228 api = GNUNET_new (struct GNUNET_BLOCK_PluginFunctions);
229 api->evaluate = &block_plugin_gns_evaluate;
230 api->get_key = &block_plugin_gns_get_key;
231 api->create_group = &block_plugin_gns_create_group;
238 * Exit point from the plugin.
241 libgnunet_plugin_block_gns_done (void *cls)
243 struct GNUNET_BLOCK_PluginFunctions *api = cls;
250 /* end of plugin_block_gns.c */