2 This file is part of GNUnet.
3 Copyright (C) 2010 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 * @author Christian Grothoff
25 * Library for data block manipulation
27 * @defgroup block Block library
28 * Library for data block manipulation
31 #ifndef GNUNET_BLOCK_LIB_H
32 #define GNUNET_BLOCK_LIB_H
34 #include "gnunet_util_lib.h"
38 #if 0 /* keep Emacsens' auto-indent happy */
45 * Blocks in the datastore and the datacache must have a unique type.
47 enum GNUNET_BLOCK_Type
50 * Any type of block, used as a wildcard when searching. Should
51 * never be attached to a specific block.
53 GNUNET_BLOCK_TYPE_ANY = 0,
56 * Data block (leaf) in the CHK tree.
58 GNUNET_BLOCK_TYPE_FS_DBLOCK = 1,
61 * Inner block in the CHK tree.
63 GNUNET_BLOCK_TYPE_FS_IBLOCK = 2,
66 * Legacy type, no longer in use.
68 GNUNET_BLOCK_TYPE_FS_KBLOCK = 3,
71 * Legacy type, no longer in use.
73 GNUNET_BLOCK_TYPE_FS_SBLOCK = 4,
76 * Legacy type, no longer in use.
78 GNUNET_BLOCK_TYPE_FS_NBLOCK = 5,
81 * Type of a block representing a block to be encoded on demand from disk.
82 * Should never appear on the network directly.
84 GNUNET_BLOCK_TYPE_FS_ONDEMAND = 6,
87 * Type of a block that contains a HELLO for a peer (for
88 * DHT and CADET find-peer operations).
90 GNUNET_BLOCK_TYPE_DHT_HELLO = 7,
95 GNUNET_BLOCK_TYPE_TEST = 8,
98 * Type of a block representing any type of search result
99 * (universal). Implemented in the context of #2564, replaces
100 * SBLOCKS, KBLOCKS and NBLOCKS.
102 GNUNET_BLOCK_TYPE_FS_UBLOCK = 9,
105 * Block for storing DNS exit service advertisements.
107 GNUNET_BLOCK_TYPE_DNS = 10,
110 * Block for storing record data
112 GNUNET_BLOCK_TYPE_GNS_NAMERECORD = 11,
115 * Block type for a revocation message by which a key is revoked.
117 GNUNET_BLOCK_TYPE_REVOCATION = 12,
120 * Block to store a cadet regex state
122 GNUNET_BLOCK_TYPE_REGEX = 22,
125 * Block to store a cadet regex accepting state
127 GNUNET_BLOCK_TYPE_REGEX_ACCEPT = 23,
130 * Block for testing set/consensus. If first byte of the block
131 * is non-zero, the block is considered invalid.
133 GNUNET_BLOCK_TYPE_SET_TEST = 24,
136 * Block type for consensus elements.
137 * Contains either special marker elements or a nested block.
139 GNUNET_BLOCK_TYPE_CONSENSUS_ELEMENT = 25,
144 * Flags that can be set to control the evaluation.
146 enum GNUNET_BLOCK_EvaluationOptions
152 GNUNET_BLOCK_EO_NONE = 0,
155 * The block is obtained from the local database, skip cryptographic
158 GNUNET_BLOCK_EO_LOCAL_SKIP_CRYPTO = 1
163 * Possible ways for how a block may relate to a query.
165 enum GNUNET_BLOCK_EvaluationResult
168 * Valid result, and there may be more.
170 GNUNET_BLOCK_EVALUATION_OK_MORE = 0,
173 * Last possible valid result.
175 GNUNET_BLOCK_EVALUATION_OK_LAST = 1,
178 * Valid result, but suppressed because it is a duplicate.
180 GNUNET_BLOCK_EVALUATION_OK_DUPLICATE = 2,
183 * Block does not match query (invalid result)
185 GNUNET_BLOCK_EVALUATION_RESULT_INVALID = 3,
188 * Block does not match xquery (valid result, not relevant for the request)
190 GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT = 4,
193 * Query is valid, no reply given.
195 GNUNET_BLOCK_EVALUATION_REQUEST_VALID = 10,
198 * Query format does not match block type (invalid query). For
199 * example, xquery not given or xquery_size not appropriate for
202 GNUNET_BLOCK_EVALUATION_REQUEST_INVALID = 11,
205 * Specified block type not supported by this plugin.
207 GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED = 20
212 * Handle to an initialized block library.
214 struct GNUNET_BLOCK_Context;
218 * Mingle hash with the mingle_number to produce different bits.
220 * @param in original hash code
221 * @param mingle_number number for hash permutation
222 * @param hc where to store the result.
225 GNUNET_BLOCK_mingle_hash (const struct GNUNET_HashCode *in,
226 uint32_t mingle_number,
227 struct GNUNET_HashCode *hc);
231 * Create a block context. Loads the block plugins.
233 * @param cfg configuration to use
234 * @return NULL on error
236 struct GNUNET_BLOCK_Context *
237 GNUNET_BLOCK_context_create (const struct GNUNET_CONFIGURATION_Handle *cfg);
241 * Destroy the block context.
243 * @param ctx context to destroy
246 GNUNET_BLOCK_context_destroy (struct GNUNET_BLOCK_Context *ctx);
250 * Handle for a group of elements that will be evaluated together.
251 * They must all be of the same type. A block group allows the
252 * plugin to keep some state across individual evaluations.
254 struct GNUNET_BLOCK_Group;
258 * Create a new block group.
260 * @param ctx block context in which the block group is created
261 * @param type type of the block for which we are creating the group
262 * @param nonce random value used to seed the group creation
263 * @param raw_data optional serialized prior state of the group, NULL if unavailable/fresh
264 * @param raw_data_size number of bytes in @a raw_data, 0 if unavailable/fresh
265 * @param ... type-specific additional data, can be empty
266 * @return block group handle, NULL if block groups are not supported
267 * by this @a type of block (this is not an error)
269 struct GNUNET_BLOCK_Group *
270 GNUNET_BLOCK_group_create (struct GNUNET_BLOCK_Context *ctx,
271 enum GNUNET_BLOCK_Type type,
273 const void *raw_data,
274 size_t raw_data_size,
279 * Serialize state of a block group.
281 * @param bg group to serialize
282 * @param[out] nonce set to the nonce of the @a bg
283 * @param[out] raw_data set to the serialized state
284 * @param[out] raw_data_size set to the number of bytes in @a raw_data
285 * @return #GNUNET_OK on success, #GNUNET_NO if serialization is not
286 * supported, #GNUNET_SYSERR on error
289 GNUNET_BLOCK_group_serialize (struct GNUNET_BLOCK_Group *bg,
292 size_t *raw_data_size);
296 * Destroy resources used by a block group.
298 * @param bg group to destroy, NULL is allowed
301 GNUNET_BLOCK_group_destroy (struct GNUNET_BLOCK_Group *bg);
305 * Function called to validate a reply or a request. For
306 * request evaluation, simply pass "NULL" for the @a reply_block.
307 * Note that it is assumed that the reply has already been
308 * matched to the key (and signatures checked) as it would
309 * be done with the #GNUNET_BLOCK_get_key() function.
311 * @param ctx block contxt
312 * @param type block type
313 * @param group block group to use for evaluation
314 * @param eo evaluation options to control evaluation
315 * @param query original query (hash)
316 * @param xquery extrended query data (can be NULL, depending on type)
317 * @param xquery_size number of bytes in @a xquery
318 * @param reply_block response to validate
319 * @param reply_block_size number of bytes in @a reply_block
320 * @return characterization of result
322 enum GNUNET_BLOCK_EvaluationResult
323 GNUNET_BLOCK_evaluate (struct GNUNET_BLOCK_Context *ctx,
324 enum GNUNET_BLOCK_Type type,
325 struct GNUNET_BLOCK_Group *group,
326 enum GNUNET_BLOCK_EvaluationOptions eo,
327 const struct GNUNET_HashCode *query,
330 const void *reply_block,
331 size_t reply_block_size);
335 * Function called to obtain the key for a block.
337 * @param ctx block context
338 * @param type block type
339 * @param block block to get the key for
340 * @param block_size number of bytes in @a block
341 * @param key set to the key (query) for the given block
342 * @return #GNUNET_YES on success,
343 * #GNUNET_NO if the block is malformed
344 * #GNUNET_SYSERR if type not supported
345 * (or if extracting a key from a block of this type does not work)
348 GNUNET_BLOCK_get_key (struct GNUNET_BLOCK_Context *ctx,
349 enum GNUNET_BLOCK_Type type,
352 struct GNUNET_HashCode *key);
356 * Update block group to filter out the given results. Note that the
357 * use of a hash for seen results implies that the caller magically
358 * knows how the specific block engine hashes for filtering
359 * duplicates, so this API may not always apply.
361 * @param bf_mutator mutation value to use
362 * @param seen_results results already seen
363 * @param seen_results_count number of entries in @a seen_results
364 * @return #GNUNET_SYSERR if not supported, #GNUNET_OK on success
367 GNUNET_BLOCK_group_set_seen (struct GNUNET_BLOCK_Group *bg,
368 const struct GNUNET_HashCode *seen_results,
369 unsigned int seen_results_count);
373 * Try merging two block groups. Afterwards, @a bg1 should remain
374 * valid and contain the rules from both @a bg1 and @bg2, and
375 * @a bg2 should be destroyed (as part of this call). The latter
376 * should happen even if merging is not supported.
378 * @param[in,out] bg1 first group to merge, is updated
379 * @param bg2 second group to merge, is destroyed
380 * @return #GNUNET_OK on success,
381 * #GNUNET_NO if merge failed due to different nonce
382 * #GNUNET_SYSERR if merging is not supported
385 GNUNET_BLOCK_group_merge (struct GNUNET_BLOCK_Group *bg1,
386 struct GNUNET_BLOCK_Group *bg2);
389 #if 0 /* keep Emacsens' auto-indent happy */
396 /* ifndef GNUNET_BLOCK_LIB_H */
399 /** @} */ /* end of group */
401 /* end of gnunet_block_lib.h */