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3 Copyright (C) 2010, 2013 GNUnet e.V.
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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
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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.
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16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18 Boston, MA 02110-1301, USA.
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 *));
69 case GNUNET_BLOCK_TYPE_FS_IBLOCK:
70 GNUNET_break (NULL == va_arg (va, const char *));
72 case GNUNET_BLOCK_TYPE_FS_UBLOCK:
73 guard = va_arg (va, const char *);
74 if (0 == strcmp (guard,
77 size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size (va_arg (va, unsigned int),
80 else if (0 == strcmp (guard,
83 size = va_arg (va, unsigned int);
87 /* va-args invalid! bad bug, complain! */
92 size = raw_data_size; /* not for us to determine, use what we got! */
93 GNUNET_break (NULL == va_arg (va, const char *));
94 return GNUNET_BLOCK_GROUP_bf_create (cls,
102 GNUNET_break (NULL == va_arg (va, const char *));
110 * Function called to validate a reply or a request. For
111 * request evaluation, simply pass "NULL" for the reply_block.
112 * Note that it is assumed that the reply has already been
113 * matched to the key (and signatures checked) as it would
114 * be done with the #GNUNET_BLOCK_get_key() function.
117 * @param ctx block context
118 * @param type block type
119 * @param bg group to use for evaluation
120 * @param eo control flags
121 * @param query original query (hash)
122 * @param xquery extrended query data (can be NULL, depending on type)
123 * @param xquery_size number of bytes in @a xquery
124 * @param reply_block response to validate
125 * @param reply_block_size number of bytes in @a reply_block
126 * @return characterization of result
128 static enum GNUNET_BLOCK_EvaluationResult
129 block_plugin_fs_evaluate (void *cls,
130 struct GNUNET_BLOCK_Context *ctx,
131 enum GNUNET_BLOCK_Type type,
132 struct GNUNET_BLOCK_Group *bg,
133 enum GNUNET_BLOCK_EvaluationOptions eo,
134 const struct GNUNET_HashCode *query,
137 const void *reply_block,
138 size_t reply_block_size)
140 const struct UBlock *ub;
141 struct GNUNET_HashCode hc;
142 struct GNUNET_HashCode chash;
146 case GNUNET_BLOCK_TYPE_FS_DBLOCK:
147 case GNUNET_BLOCK_TYPE_FS_IBLOCK:
148 if (0 != xquery_size)
151 return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
153 if (NULL == reply_block)
154 return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
155 return GNUNET_BLOCK_EVALUATION_OK_LAST;
156 case GNUNET_BLOCK_TYPE_FS_UBLOCK:
157 if (0 != xquery_size)
160 return GNUNET_BLOCK_EVALUATION_REQUEST_INVALID;
162 if (NULL == reply_block)
163 return GNUNET_BLOCK_EVALUATION_REQUEST_VALID;
165 if (reply_block_size < sizeof (struct UBlock))
168 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
171 GNUNET_CRYPTO_hash (&ub->verification_key,
172 sizeof (ub->verification_key),
174 if (0 != memcmp (&hc,
176 sizeof (struct GNUNET_HashCode)))
179 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
181 if (reply_block_size != ntohl (ub->purpose.size) + sizeof (struct GNUNET_CRYPTO_EcdsaSignature))
184 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
186 if ( (0 == (eo & GNUNET_BLOCK_EO_LOCAL_SKIP_CRYPTO)) &&
188 GNUNET_CRYPTO_ecdsa_verify (GNUNET_SIGNATURE_PURPOSE_FS_UBLOCK,
191 &ub->verification_key)) )
194 return GNUNET_BLOCK_EVALUATION_RESULT_INVALID;
196 GNUNET_CRYPTO_hash (reply_block,
200 GNUNET_BLOCK_GROUP_bf_test_and_set (bg,
202 return GNUNET_BLOCK_EVALUATION_OK_DUPLICATE;
203 return GNUNET_BLOCK_EVALUATION_OK_MORE;
205 return GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED;
211 * Function called to obtain the key for a block.
214 * @param type block type
215 * @param block block to get the key for
216 * @param block_size number of bytes in @a block
217 * @param key set to the key (query) for the given block
218 * @return #GNUNET_OK on success, #GNUNET_SYSERR if type not supported
219 * (or if extracting a key from a block of this type does not work)
222 block_plugin_fs_get_key (void *cls,
223 enum GNUNET_BLOCK_Type type,
226 struct GNUNET_HashCode *key)
228 const struct UBlock *ub;
232 case GNUNET_BLOCK_TYPE_FS_DBLOCK:
233 case GNUNET_BLOCK_TYPE_FS_IBLOCK:
234 GNUNET_CRYPTO_hash (block, block_size, key);
236 case GNUNET_BLOCK_TYPE_FS_UBLOCK:
237 if (block_size < sizeof (struct UBlock))
240 return GNUNET_SYSERR;
243 GNUNET_CRYPTO_hash (&ub->verification_key,
244 sizeof (ub->verification_key),
249 return GNUNET_SYSERR;
255 * Entry point for the plugin.
258 libgnunet_plugin_block_fs_init (void *cls)
260 static enum GNUNET_BLOCK_Type types[] =
262 GNUNET_BLOCK_TYPE_FS_DBLOCK,
263 GNUNET_BLOCK_TYPE_FS_IBLOCK,
264 GNUNET_BLOCK_TYPE_FS_UBLOCK,
265 GNUNET_BLOCK_TYPE_ANY /* end of list */
267 struct GNUNET_BLOCK_PluginFunctions *api;
269 api = GNUNET_new (struct GNUNET_BLOCK_PluginFunctions);
270 api->evaluate = &block_plugin_fs_evaluate;
271 api->get_key = &block_plugin_fs_get_key;
272 api->create_group = &block_plugin_fs_create_group;
279 * Exit point from the plugin.
282 libgnunet_plugin_block_fs_done (void *cls)
284 struct GNUNET_BLOCK_PluginFunctions *api = cls;
290 /* end of plugin_block_fs.c */