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6 under the terms of the GNU General Public License as published
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17 * @author Christian Grothoff
20 * Library for data block manipulation
22 * @defgroup block Block library
23 * Library for data block manipulation
26 #ifndef GNUNET_BLOCK_LIB_H
27 #define GNUNET_BLOCK_LIB_H
29 #include "gnunet_util_lib.h"
33 #if 0 /* keep Emacsens' auto-indent happy */
40 * Blocks in the datastore and the datacache must have a unique type.
42 enum GNUNET_BLOCK_Type
45 * Any type of block, used as a wildcard when searching. Should
46 * never be attached to a specific block.
48 GNUNET_BLOCK_TYPE_ANY = 0,
51 * Data block (leaf) in the CHK tree.
53 GNUNET_BLOCK_TYPE_FS_DBLOCK = 1,
56 * Inner block in the CHK tree.
58 GNUNET_BLOCK_TYPE_FS_IBLOCK = 2,
61 * Legacy type, no longer in use.
63 GNUNET_BLOCK_TYPE_FS_KBLOCK = 3,
66 * Legacy type, no longer in use.
68 GNUNET_BLOCK_TYPE_FS_SBLOCK = 4,
71 * Legacy type, no longer in use.
73 GNUNET_BLOCK_TYPE_FS_NBLOCK = 5,
76 * Type of a block representing a block to be encoded on demand from disk.
77 * Should never appear on the network directly.
79 GNUNET_BLOCK_TYPE_FS_ONDEMAND = 6,
82 * Type of a block that contains a HELLO for a peer (for
83 * DHT and CADET find-peer operations).
85 GNUNET_BLOCK_TYPE_DHT_HELLO = 7,
90 GNUNET_BLOCK_TYPE_TEST = 8,
93 * Type of a block representing any type of search result
94 * (universal). Implemented in the context of #2564, replaces
95 * SBLOCKS, KBLOCKS and NBLOCKS.
97 GNUNET_BLOCK_TYPE_FS_UBLOCK = 9,
100 * Block for storing DNS exit service advertisements.
102 GNUNET_BLOCK_TYPE_DNS = 10,
105 * Block for storing record data
107 GNUNET_BLOCK_TYPE_GNS_NAMERECORD = 11,
110 * Block type for a revocation message by which a key is revoked.
112 GNUNET_BLOCK_TYPE_REVOCATION = 12,
115 * Block to store a cadet regex state
117 GNUNET_BLOCK_TYPE_REGEX = 22,
120 * Block to store a cadet regex accepting state
122 GNUNET_BLOCK_TYPE_REGEX_ACCEPT = 23,
125 * Block for testing set/consensus. If first byte of the block
126 * is non-zero, the block is considered invalid.
128 GNUNET_BLOCK_TYPE_SET_TEST = 24,
131 * Block type for consensus elements.
132 * Contains either special marker elements or a nested block.
134 GNUNET_BLOCK_TYPE_CONSENSUS_ELEMENT = 25,
139 * Flags that can be set to control the evaluation.
141 enum GNUNET_BLOCK_EvaluationOptions
147 GNUNET_BLOCK_EO_NONE = 0,
150 * The block is obtained from the local database, skip cryptographic
153 GNUNET_BLOCK_EO_LOCAL_SKIP_CRYPTO = 1
158 * Possible ways for how a block may relate to a query.
160 enum GNUNET_BLOCK_EvaluationResult
163 * Valid result, and there may be more.
165 GNUNET_BLOCK_EVALUATION_OK_MORE = 0,
168 * Last possible valid result.
170 GNUNET_BLOCK_EVALUATION_OK_LAST = 1,
173 * Valid result, but suppressed because it is a duplicate.
175 GNUNET_BLOCK_EVALUATION_OK_DUPLICATE = 2,
178 * Block does not match query (invalid result)
180 GNUNET_BLOCK_EVALUATION_RESULT_INVALID = 3,
183 * Block does not match xquery (valid result, not relevant for the request)
185 GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT = 4,
188 * Query is valid, no reply given.
190 GNUNET_BLOCK_EVALUATION_REQUEST_VALID = 10,
193 * Query format does not match block type (invalid query). For
194 * example, xquery not given or xquery_size not appropriate for
197 GNUNET_BLOCK_EVALUATION_REQUEST_INVALID = 11,
200 * Specified block type not supported by this plugin.
202 GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED = 20
207 * Handle to an initialized block library.
209 struct GNUNET_BLOCK_Context;
213 * Mingle hash with the mingle_number to produce different bits.
215 * @param in original hash code
216 * @param mingle_number number for hash permutation
217 * @param hc where to store the result.
220 GNUNET_BLOCK_mingle_hash (const struct GNUNET_HashCode *in,
221 uint32_t mingle_number,
222 struct GNUNET_HashCode *hc);
226 * Create a block context. Loads the block plugins.
228 * @param cfg configuration to use
229 * @return NULL on error
231 struct GNUNET_BLOCK_Context *
232 GNUNET_BLOCK_context_create (const struct GNUNET_CONFIGURATION_Handle *cfg);
236 * Destroy the block context.
238 * @param ctx context to destroy
241 GNUNET_BLOCK_context_destroy (struct GNUNET_BLOCK_Context *ctx);
245 * Handle for a group of elements that will be evaluated together.
246 * They must all be of the same type. A block group allows the
247 * plugin to keep some state across individual evaluations.
249 struct GNUNET_BLOCK_Group;
253 * Create a new block group.
255 * @param ctx block context in which the block group is created
256 * @param type type of the block for which we are creating the group
257 * @param nonce random value used to seed the group creation
258 * @param raw_data optional serialized prior state of the group, NULL if unavailable/fresh
259 * @param raw_data_size number of bytes in @a raw_data, 0 if unavailable/fresh
260 * @param ... type-specific additional data, can be empty
261 * @return block group handle, NULL if block groups are not supported
262 * by this @a type of block (this is not an error)
264 struct GNUNET_BLOCK_Group *
265 GNUNET_BLOCK_group_create (struct GNUNET_BLOCK_Context *ctx,
266 enum GNUNET_BLOCK_Type type,
268 const void *raw_data,
269 size_t raw_data_size,
274 * Serialize state of a block group.
276 * @param bg group to serialize
277 * @param[out] nonce set to the nonce of the @a bg
278 * @param[out] raw_data set to the serialized state
279 * @param[out] raw_data_size set to the number of bytes in @a raw_data
280 * @return #GNUNET_OK on success, #GNUNET_NO if serialization is not
281 * supported, #GNUNET_SYSERR on error
284 GNUNET_BLOCK_group_serialize (struct GNUNET_BLOCK_Group *bg,
287 size_t *raw_data_size);
291 * Destroy resources used by a block group.
293 * @param bg group to destroy, NULL is allowed
296 GNUNET_BLOCK_group_destroy (struct GNUNET_BLOCK_Group *bg);
300 * Function called to validate a reply or a request. For
301 * request evaluation, simply pass "NULL" for the @a reply_block.
302 * Note that it is assumed that the reply has already been
303 * matched to the key (and signatures checked) as it would
304 * be done with the #GNUNET_BLOCK_get_key() function.
306 * @param ctx block contxt
307 * @param type block type
308 * @param group block group to use for evaluation
309 * @param eo evaluation options to control evaluation
310 * @param query original query (hash)
311 * @param xquery extrended query data (can be NULL, depending on type)
312 * @param xquery_size number of bytes in @a xquery
313 * @param reply_block response to validate
314 * @param reply_block_size number of bytes in @a reply_block
315 * @return characterization of result
317 enum GNUNET_BLOCK_EvaluationResult
318 GNUNET_BLOCK_evaluate (struct GNUNET_BLOCK_Context *ctx,
319 enum GNUNET_BLOCK_Type type,
320 struct GNUNET_BLOCK_Group *group,
321 enum GNUNET_BLOCK_EvaluationOptions eo,
322 const struct GNUNET_HashCode *query,
325 const void *reply_block,
326 size_t reply_block_size);
330 * Function called to obtain the key for a block.
332 * @param ctx block context
333 * @param type block type
334 * @param block block to get the key for
335 * @param block_size number of bytes in @a block
336 * @param key set to the key (query) for the given block
337 * @return #GNUNET_YES on success,
338 * #GNUNET_NO if the block is malformed
339 * #GNUNET_SYSERR if type not supported
340 * (or if extracting a key from a block of this type does not work)
343 GNUNET_BLOCK_get_key (struct GNUNET_BLOCK_Context *ctx,
344 enum GNUNET_BLOCK_Type type,
347 struct GNUNET_HashCode *key);
351 * Update block group to filter out the given results. Note that the
352 * use of a hash for seen results implies that the caller magically
353 * knows how the specific block engine hashes for filtering
354 * duplicates, so this API may not always apply.
356 * @param bf_mutator mutation value to use
357 * @param seen_results results already seen
358 * @param seen_results_count number of entries in @a seen_results
359 * @return #GNUNET_SYSERR if not supported, #GNUNET_OK on success
362 GNUNET_BLOCK_group_set_seen (struct GNUNET_BLOCK_Group *bg,
363 const struct GNUNET_HashCode *seen_results,
364 unsigned int seen_results_count);
368 * Try merging two block groups. Afterwards, @a bg1 should remain
369 * valid and contain the rules from both @a bg1 and @bg2, and
370 * @a bg2 should be destroyed (as part of this call). The latter
371 * should happen even if merging is not supported.
373 * @param[in,out] bg1 first group to merge, is updated
374 * @param bg2 second group to merge, is destroyed
375 * @return #GNUNET_OK on success,
376 * #GNUNET_NO if merge failed due to different nonce
377 * #GNUNET_SYSERR if merging is not supported
380 GNUNET_BLOCK_group_merge (struct GNUNET_BLOCK_Group *bg1,
381 struct GNUNET_BLOCK_Group *bg2);
384 #if 0 /* keep Emacsens' auto-indent happy */
391 /* ifndef GNUNET_BLOCK_LIB_H */
394 /** @} */ /* end of group */
396 /* end of gnunet_block_lib.h */