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 fs/plugin_block_fs.c
23 * @brief blocks used for file-sharing
24 * @author Christian Grothoff
27 #include "gnunet_block_plugin.h"
28 #include "gnunet_fs_service.h"
30 #include "gnunet_signatures.h"
31 #include "gnunet_block_group_lib.h"
35 * Number of bits we set per entry in the bloomfilter.
38 #define BLOOMFILTER_K 16
42 * Create a new block group.
44 * @param ctx block context in which the block group is created
45 * @param type type of the block for which we are creating the group
46 * @param nonce random value used to seed the group creation
47 * @param raw_data optional serialized prior state of the group, NULL if unavailable/fresh
48 * @param raw_data_size number of bytes in @a raw_data, 0 if unavailable/fresh
49 * @param va variable arguments specific to @a type
50 * @return block group handle, NULL if block groups are not supported
51 * by this @a type of block (this is not an error)
53 static struct GNUNET_BLOCK_Group *
54 block_plugin_fs_create_group (void *cls,
55 enum GNUNET_BLOCK_Type type,
66 case GNUNET_BLOCK_TYPE_FS_DBLOCK:
67 GNUNET_break (NULL == va_arg (va, const char *));
70 case GNUNET_BLOCK_TYPE_FS_IBLOCK:
71 GNUNET_break (NULL == va_arg (va, const char *));
74 case GNUNET_BLOCK_TYPE_FS_UBLOCK:
75 guard = va_arg (va, const char *);
76 if (0 == strcmp (guard,
79 size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size (va_arg (va, unsigned
83 else if (0 == strcmp (guard,
86 size = va_arg (va, unsigned int);
90 /* va-args invalid! bad bug, complain! */
95 size = raw_data_size; /* not for us to determine, use what we got! */
96 GNUNET_break (NULL == va_arg (va, const char *));
97 return GNUNET_BLOCK_GROUP_bf_create (cls,
106 GNUNET_break (NULL == va_arg (va, const char *));
114 * Function called to validate a reply or a request. For
115 * request evaluation, simply pass "NULL" for the reply_block.
116 * Note that it is assumed that the reply has already been
117 * matched to the key (and signatures checked) as it would
118 * be done with the #GNUNET_BLOCK_get_key() function.
121 * @param ctx block context
122 * @param type block type
123 * @param bg group to use for evaluation
124 * @param eo control flags
125 * @param query original query (hash)
126 * @param xquery extrended query data (can be NULL, depending on type)
127 * @param xquery_size number of bytes in @a xquery
128 * @param reply_block response to validate
129 * @param reply_block_size number of bytes in @a reply_block
130 * @return characterization of result
132 static enum GNUNET_BLOCK_EvaluationResult
133 block_plugin_fs_evaluate (void *cls,
134 struct GNUNET_BLOCK_Context *ctx,
135 enum GNUNET_BLOCK_Type type,
136 struct GNUNET_BLOCK_Group *bg,
137 enum GNUNET_BLOCK_EvaluationOptions eo,
138 const struct GNUNET_HashCode *query,
141 const void *reply_block,
142 size_t reply_block_size)
144 const struct UBlock *ub;
145 struct GNUNET_HashCode hc;
146 struct GNUNET_HashCode chash;
150 case GNUNET_BLOCK_TYPE_FS_DBLOCK:
151 case GNUNET_BLOCK_TYPE_FS_IBLOCK:
152 if (0 != xquery_size)
155 return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
157 if (NULL == reply_block)
158 return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
159 return GNUNET_BLOCK_EVALUATION_OK_LAST;
161 case GNUNET_BLOCK_TYPE_FS_UBLOCK:
162 if (0 != xquery_size)
165 return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
167 if (NULL == reply_block)
168 return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
170 if (reply_block_size < sizeof(struct UBlock))
173 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
176 GNUNET_CRYPTO_hash (&ub->verification_key,
177 sizeof(ub->verification_key),
179 if (0 != memcmp (&hc,
181 sizeof(struct GNUNET_HashCode)))
184 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
186 if (reply_block_size != ntohl (ub->purpose.size) + sizeof(struct
187 GNUNET_CRYPTO_EcdsaSignature))
190 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
192 if ((0 == (eo & GNUNET_BLOCK_EO_LOCAL_SKIP_CRYPTO)) &&
194 GNUNET_CRYPTO_ecdsa_verify_ (GNUNET_SIGNATURE_PURPOSE_FS_UBLOCK,
197 &ub->verification_key)))
200 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
202 GNUNET_CRYPTO_hash (reply_block,
206 GNUNET_BLOCK_GROUP_bf_test_and_set (bg,
208 return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
209 return GNUNET_BLOCK_EVALUATION_OK_MORE;
212 return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
218 * Function called to obtain the key for a block.
221 * @param type block type
222 * @param block block to get the key for
223 * @param block_size number of bytes in @a block
224 * @param key set to the key (query) for the given block
225 * @return #GNUNET_OK on success, #GNUNET_SYSERR if type not supported
226 * (or if extracting a key from a block of this type does not work)
229 block_plugin_fs_get_key (void *cls,
230 enum GNUNET_BLOCK_Type type,
233 struct GNUNET_HashCode *key)
235 const struct UBlock *ub;
239 case GNUNET_BLOCK_TYPE_FS_DBLOCK:
240 case GNUNET_BLOCK_TYPE_FS_IBLOCK:
241 GNUNET_CRYPTO_hash (block, block_size, key);
244 case GNUNET_BLOCK_TYPE_FS_UBLOCK:
245 if (block_size < sizeof(struct UBlock))
248 return GNUNET_SYSERR;
251 GNUNET_CRYPTO_hash (&ub->verification_key,
252 sizeof(ub->verification_key),
258 return GNUNET_SYSERR;
264 * Entry point for the plugin.
267 libgnunet_plugin_block_fs_init (void *cls)
269 static enum GNUNET_BLOCK_Type types[] = {
270 GNUNET_BLOCK_TYPE_FS_DBLOCK,
271 GNUNET_BLOCK_TYPE_FS_IBLOCK,
272 GNUNET_BLOCK_TYPE_FS_UBLOCK,
273 GNUNET_BLOCK_TYPE_ANY /* end of list */
275 struct GNUNET_BLOCK_PluginFunctions *api;
277 api = GNUNET_new (struct GNUNET_BLOCK_PluginFunctions);
278 api->evaluate = &block_plugin_fs_evaluate;
279 api->get_key = &block_plugin_fs_get_key;
280 api->create_group = &block_plugin_fs_create_group;
287 * Exit point from the plugin.
290 libgnunet_plugin_block_fs_done (void *cls)
292 struct GNUNET_BLOCK_PluginFunctions *api = cls;
299 /* end of plugin_block_fs.c */