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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 {
49 * Any type of block, used as a wildcard when searching. Should
50 * never be attached to a specific block.
52 GNUNET_BLOCK_TYPE_ANY = 0,
55 * Data block (leaf) in the CHK tree.
57 GNUNET_BLOCK_TYPE_FS_DBLOCK = 1,
60 * Inner block in the CHK tree.
62 GNUNET_BLOCK_TYPE_FS_IBLOCK = 2,
65 * Legacy type, no longer in use.
67 GNUNET_BLOCK_TYPE_FS_KBLOCK = 3,
70 * Legacy type, no longer in use.
72 GNUNET_BLOCK_TYPE_FS_SBLOCK = 4,
75 * Legacy type, no longer in use.
77 GNUNET_BLOCK_TYPE_FS_NBLOCK = 5,
80 * Type of a block representing a block to be encoded on demand from disk.
81 * Should never appear on the network directly.
83 GNUNET_BLOCK_TYPE_FS_ONDEMAND = 6,
86 * Type of a block that contains a HELLO for a peer (for
87 * DHT and CADET find-peer operations).
89 GNUNET_BLOCK_TYPE_DHT_HELLO = 7,
94 GNUNET_BLOCK_TYPE_TEST = 8,
97 * Type of a block representing any type of search result
98 * (universal). Implemented in the context of #2564, replaces
99 * SBLOCKS, KBLOCKS and NBLOCKS.
101 GNUNET_BLOCK_TYPE_FS_UBLOCK = 9,
104 * Block for storing DNS exit service advertisements.
106 GNUNET_BLOCK_TYPE_DNS = 10,
109 * Block for storing record data
111 GNUNET_BLOCK_TYPE_GNS_NAMERECORD = 11,
114 * Block type for a revocation message by which a key is revoked.
116 GNUNET_BLOCK_TYPE_REVOCATION = 12,
119 * Block to store a cadet regex state
121 GNUNET_BLOCK_TYPE_REGEX = 22,
124 * Block to store a cadet regex accepting state
126 GNUNET_BLOCK_TYPE_REGEX_ACCEPT = 23,
129 * Block for testing set/consensus. If first byte of the block
130 * is non-zero, the block is considered invalid.
132 GNUNET_BLOCK_TYPE_SET_TEST = 24,
135 * Block type for consensus elements.
136 * Contains either special marker elements or a nested block.
138 GNUNET_BLOCK_TYPE_CONSENSUS_ELEMENT = 25,
143 * Flags that can be set to control the evaluation.
145 enum GNUNET_BLOCK_EvaluationOptions {
149 GNUNET_BLOCK_EO_NONE = 0,
152 * The block is obtained from the local database, skip cryptographic
155 GNUNET_BLOCK_EO_LOCAL_SKIP_CRYPTO = 1
160 * Possible ways for how a block may relate to a query.
162 enum GNUNET_BLOCK_EvaluationResult {
164 * Valid result, and there may be more.
166 GNUNET_BLOCK_EVALUATION_OK_MORE = 0,
169 * Last possible valid result.
171 GNUNET_BLOCK_EVALUATION_OK_LAST = 1,
174 * Valid result, but suppressed because it is a duplicate.
176 GNUNET_BLOCK_EVALUATION_OK_DUPLICATE = 2,
179 * Block does not match query (invalid result)
181 GNUNET_BLOCK_EVALUATION_RESULT_INVALID = 3,
184 * Block does not match xquery (valid result, not relevant for the request)
186 GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT = 4,
189 * Query is valid, no reply given.
191 GNUNET_BLOCK_EVALUATION_REQUEST_VALID = 10,
194 * Query format does not match block type (invalid query). For
195 * example, xquery not given or xquery_size not appropriate for
198 GNUNET_BLOCK_EVALUATION_REQUEST_INVALID = 11,
201 * Specified block type not supported by this plugin.
203 GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED = 20
208 * Handle to an initialized block library.
210 struct GNUNET_BLOCK_Context;
214 * Mingle hash with the mingle_number to produce different bits.
216 * @param in original hash code
217 * @param mingle_number number for hash permutation
218 * @param hc where to store the result.
221 GNUNET_BLOCK_mingle_hash(const struct GNUNET_HashCode *in,
222 uint32_t mingle_number,
223 struct GNUNET_HashCode *hc);
227 * Create a block context. Loads the block plugins.
229 * @param cfg configuration to use
230 * @return NULL on error
232 struct GNUNET_BLOCK_Context *
233 GNUNET_BLOCK_context_create(const struct GNUNET_CONFIGURATION_Handle *cfg);
237 * Destroy the block context.
239 * @param ctx context to destroy
242 GNUNET_BLOCK_context_destroy(struct GNUNET_BLOCK_Context *ctx);
246 * Handle for a group of elements that will be evaluated together.
247 * They must all be of the same type. A block group allows the
248 * plugin to keep some state across individual evaluations.
250 struct GNUNET_BLOCK_Group;
254 * Create a new block group.
256 * @param ctx block context in which the block group is created
257 * @param type type of the block for which we are creating the group
258 * @param nonce random value used to seed the group creation
259 * @param raw_data optional serialized prior state of the group, NULL if unavailable/fresh
260 * @param raw_data_size number of bytes in @a raw_data, 0 if unavailable/fresh
261 * @param ... type-specific additional data, can be empty
262 * @return block group handle, NULL if block groups are not supported
263 * by this @a type of block (this is not an error)
265 struct GNUNET_BLOCK_Group *
266 GNUNET_BLOCK_group_create(struct GNUNET_BLOCK_Context *ctx,
267 enum GNUNET_BLOCK_Type type,
269 const void *raw_data,
270 size_t raw_data_size,
275 * Serialize state of a block group.
277 * @param bg group to serialize
278 * @param[out] nonce set to the nonce of the @a bg
279 * @param[out] raw_data set to the serialized state
280 * @param[out] raw_data_size set to the number of bytes in @a raw_data
281 * @return #GNUNET_OK on success, #GNUNET_NO if serialization is not
282 * supported, #GNUNET_SYSERR on error
285 GNUNET_BLOCK_group_serialize(struct GNUNET_BLOCK_Group *bg,
288 size_t *raw_data_size);
292 * Destroy resources used by a block group.
294 * @param bg group to destroy, NULL is allowed
297 GNUNET_BLOCK_group_destroy(struct GNUNET_BLOCK_Group *bg);
301 * Function called to validate a reply or a request. For
302 * request evaluation, simply pass "NULL" for the @a reply_block.
303 * Note that it is assumed that the reply has already been
304 * matched to the key (and signatures checked) as it would
305 * be done with the #GNUNET_BLOCK_get_key() function.
307 * @param ctx block contxt
308 * @param type block type
309 * @param group block group to use for evaluation
310 * @param eo evaluation options to control evaluation
311 * @param query original query (hash)
312 * @param xquery extrended query data (can be NULL, depending on type)
313 * @param xquery_size number of bytes in @a xquery
314 * @param reply_block response to validate
315 * @param reply_block_size number of bytes in @a reply_block
316 * @return characterization of result
318 enum GNUNET_BLOCK_EvaluationResult
319 GNUNET_BLOCK_evaluate(struct GNUNET_BLOCK_Context *ctx,
320 enum GNUNET_BLOCK_Type type,
321 struct GNUNET_BLOCK_Group *group,
322 enum GNUNET_BLOCK_EvaluationOptions eo,
323 const struct GNUNET_HashCode *query,
326 const void *reply_block,
327 size_t reply_block_size);
331 * Function called to obtain the key for a block.
333 * @param ctx block context
334 * @param type block type
335 * @param block block to get the key for
336 * @param block_size number of bytes in @a block
337 * @param key set to the key (query) for the given block
338 * @return #GNUNET_YES on success,
339 * #GNUNET_NO if the block is malformed
340 * #GNUNET_SYSERR if type not supported
341 * (or if extracting a key from a block of this type does not work)
344 GNUNET_BLOCK_get_key(struct GNUNET_BLOCK_Context *ctx,
345 enum GNUNET_BLOCK_Type type,
348 struct GNUNET_HashCode *key);
352 * Update block group to filter out the given results. Note that the
353 * use of a hash for seen results implies that the caller magically
354 * knows how the specific block engine hashes for filtering
355 * duplicates, so this API may not always apply.
357 * @param bf_mutator mutation value to use
358 * @param seen_results results already seen
359 * @param seen_results_count number of entries in @a seen_results
360 * @return #GNUNET_SYSERR if not supported, #GNUNET_OK on success
363 GNUNET_BLOCK_group_set_seen(struct GNUNET_BLOCK_Group *bg,
364 const struct GNUNET_HashCode *seen_results,
365 unsigned int seen_results_count);
369 * Try merging two block groups. Afterwards, @a bg1 should remain
370 * valid and contain the rules from both @a bg1 and @bg2, and
371 * @a bg2 should be destroyed (as part of this call). The latter
372 * should happen even if merging is not supported.
374 * @param[in,out] bg1 first group to merge, is updated
375 * @param bg2 second group to merge, is destroyed
376 * @return #GNUNET_OK on success,
377 * #GNUNET_NO if merge failed due to different nonce
378 * #GNUNET_SYSERR if merging is not supported
381 GNUNET_BLOCK_group_merge(struct GNUNET_BLOCK_Group *bg1,
382 struct GNUNET_BLOCK_Group *bg2);
385 #if 0 /* keep Emacsens' auto-indent happy */
392 /* ifndef GNUNET_BLOCK_LIB_H */
395 /** @} */ /* end of group */
397 /* end of gnunet_block_lib.h */