2 This file is part of GNUnet
3 (C) 2012, 2013 Christian Grothoff (and other contributing authors)
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22 * @file include/gnunet_namestore_service.h
23 * @brief API that can be used to store naming information on a GNUnet node;
24 * Naming information can either be records for which this peer/user
25 * is authoritative, or blocks which are cached, encrypted naming
26 * data from other peers.
27 * @author Christian Grothoff
29 #ifndef GNUNET_NAMESTORE_SERVICE_H
30 #define GNUNET_NAMESTORE_SERVICE_H
32 #include "gnunet_util_lib.h"
33 #include "gnunet_block_lib.h"
38 #if 0 /* keep Emacsens' auto-indent happy */
44 * Record type indicating any record/'*'
46 #define GNUNET_NAMESTORE_TYPE_ANY 0
49 * Record type for GNS zone transfer ("PKEY").
51 #define GNUNET_NAMESTORE_TYPE_PKEY 65536
54 * Record type for GNS zone transfer ("PSEU").
56 #define GNUNET_NAMESTORE_TYPE_PSEU 65537
59 * Record type for GNS legacy hostnames ("LEHO").
61 #define GNUNET_NAMESTORE_TYPE_LEHO 65538
64 * Record type for VPN resolution
66 #define GNUNET_NAMESTORE_TYPE_VPN 65539
69 * Record type for zone revocation
71 #define GNUNET_NAMESTORE_TYPE_REV 65540
74 * Record type for a social place.
76 #define GNUNET_NAMESTORE_TYPE_PLACE 65541
81 struct GNUNET_NAMESTORE_QueueEntry;
84 * Handle to the namestore service.
86 struct GNUNET_NAMESTORE_Handle;
89 * Handle to the namestore zone iterator.
91 struct GNUNET_NAMESTORE_ZoneIterator;
94 * Maximum size of a value that can be stored in the namestore.
96 #define GNUNET_NAMESTORE_MAX_VALUE_SIZE (63 * 1024)
100 * Connect to the namestore service.
102 * @param cfg configuration to use
103 * @return handle to use to access the service
105 struct GNUNET_NAMESTORE_Handle *
106 GNUNET_NAMESTORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg);
110 * Disconnect from the namestore service (and free associated
113 * @param h handle to the namestore
116 GNUNET_NAMESTORE_disconnect (struct GNUNET_NAMESTORE_Handle *h);
120 * Continuation called to notify client about result of the
124 * @param success GNUNET_SYSERR on failure (including timeout/queue drop/failure to validate)
125 * GNUNET_NO if content was already there or not found
126 * GNUNET_YES (or other positive value) on success
127 * @param emsg NULL on success, otherwise an error message
129 typedef void (*GNUNET_NAMESTORE_ContinuationWithStatus) (void *cls,
135 * Flags that can be set for a record.
137 enum GNUNET_NAMESTORE_RecordFlags
141 * No special options.
143 GNUNET_NAMESTORE_RF_NONE = 0,
146 * This peer is the authority for this record; it must thus
147 * not be deleted (other records can be deleted if we run
150 GNUNET_NAMESTORE_RF_AUTHORITY = 1,
153 * This is a private record of this peer and it should
154 * thus not be handed out to other peers.
156 GNUNET_NAMESTORE_RF_PRIVATE = 2,
159 * This record was added by the system
160 * and is pending user confimation
162 GNUNET_NAMESTORE_RF_PENDING = 4,
165 * This expiration time of the record is a relative
166 * time (not an absolute time).
168 GNUNET_NAMESTORE_RF_RELATIVE_EXPIRATION = 8,
171 * This record should not be used unless all (other) records with an absolute
172 * expiration time have expired.
174 GNUNET_NAMESTORE_RF_SHADOW_RECORD = 16
177 * When comparing flags for record equality for removal,
178 * which flags should must match (in addition to the type,
179 * name, expiration value and data of the record)? All flags
180 * that are not listed here will be ignored for this purpose.
181 * (for example, we don't expect that users will remember to
182 * pass the '--private' option when removing a record from
183 * the namestore, hence we don't require this particular option
184 * to match upon removal). See also
185 * 'GNUNET_NAMESTORE_records_cmp'.
187 #define GNUNET_NAMESTORE_RF_RCMP_FLAGS (GNUNET_NAMESTORE_RF_RELATIVE_EXPIRATION)
194 struct GNUNET_NAMESTORE_RecordData
198 * Binary value stored in the DNS record.
199 * FIXME: goofy API: sometimes 'data' is individually
200 * 'malloc'ed, sometimes it points into some existing
201 * data area (so sometimes this should be a 'void *',
202 * sometimes a 'const void *'). This is unclean.
207 * Expiration time for the DNS record. Can be relative
208 * or absolute, depending on 'flags'.
210 uint64_t expiration_time;
213 * Number of bytes in 'data'.
218 * Type of the GNS/DNS record.
220 uint32_t record_type;
223 * Flags for the record.
225 enum GNUNET_NAMESTORE_RecordFlags flags;
230 * Information we have in an encrypted block with record data (i.e. in the DHT).
232 struct GNUNET_NAMESTORE_Block
236 * Signature of the block.
238 struct GNUNET_CRYPTO_EccSignature signature;
241 * Derived key used for signing; hash of this is the query.
243 struct GNUNET_CRYPTO_EccPublicKey derived_key;
246 * Number of bytes signed; also specifies the number of bytes
247 * of encrypted data that follow.
249 struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
252 * Expiration time of the block.
254 struct GNUNET_TIME_AbsoluteNBO expiration_time;
256 /* followed by encrypted data */
261 * Store an item in the namestore. If the item is already present,
262 * it is replaced with the new record.
264 * @param h handle to the namestore
265 * @param block block to store
266 * @param cont continuation to call when done
267 * @param cont_cls closure for cont
268 * @return handle to abort the request
270 struct GNUNET_NAMESTORE_QueueEntry *
271 GNUNET_NAMESTORE_block_cache (struct GNUNET_NAMESTORE_Handle *h,
272 const struct GNUNET_NAMESTORE_Block *block,
273 GNUNET_NAMESTORE_ContinuationWithStatus cont,
278 * Store an item in the namestore. If the item is already present,
279 * it is replaced with the new record. Use an empty array to
280 * remove all records under the given name.
282 * @param h handle to the namestore
283 * @param pkey private key of the zone
284 * @param label name that is being mapped (at most 255 characters long)
285 * @param rd_count number of records in the 'rd' array
286 * @param rd array of records with data to store
287 * @param cont continuation to call when done
288 * @param cont_cls closure for 'cont'
289 * @return handle to abort the request
291 struct GNUNET_NAMESTORE_QueueEntry *
292 GNUNET_NAMESTORE_records_store (struct GNUNET_NAMESTORE_Handle *h,
293 const struct GNUNET_CRYPTO_EccPrivateKey *pkey,
295 unsigned int rd_count,
296 const struct GNUNET_NAMESTORE_RecordData *rd,
297 GNUNET_NAMESTORE_ContinuationWithStatus cont,
302 * Process a record that was stored in the namestore.
305 * @param block block that was stored in the namestore
307 typedef void (*GNUNET_NAMESTORE_BlockProcessor) (void *cls,
308 const struct GNUNET_NAMESTORE_Block *block);
312 * Get a result for a particular key from the namestore. The processor
313 * will only be called once.
315 * @param h handle to the namestore
316 * @param derived_hash hash of zone key combined with name to lookup
317 * @param proc function to call on the matching block, or with
318 * NULL if there is no matching block
319 * @param proc_cls closure for proc
320 * @return a handle that can be used to cancel
322 struct GNUNET_NAMESTORE_QueueEntry *
323 GNUNET_NAMESTORE_lookup_block (struct GNUNET_NAMESTORE_Handle *h,
324 const struct GNUNET_HashCode *derived_hash,
325 GNUNET_NAMESTORE_BlockProcessor proc, void *proc_cls);
329 * Process a record that was stored in the namestore.
332 * @param zone private key of the zone
333 * @param label label of the records
334 * @param rd_count number of entries in 'rd' array
335 * @param rd array of records with data to store
337 typedef void (*GNUNET_NAMESTORE_RecordMonitor) (void *cls,
338 const struct GNUNET_CRYPTO_EccPrivateKey *zone,
340 unsigned int rd_count,
341 const struct GNUNET_NAMESTORE_RecordData *rd);
345 * Look for an existing PKEY delegation record for a given public key.
346 * Returns at most one result to the processor.
348 * @param h handle to the namestore
349 * @param zone public key of the zone to look up in, never NULL
350 * @param value_zone public key of the target zone (value), never NULL
351 * @param proc function to call on the matching records, or with
352 * NULL (rd_count == 0) if there are no matching records
353 * @param proc_cls closure for proc
354 * @return a handle that can be used to
357 struct GNUNET_NAMESTORE_QueueEntry *
358 GNUNET_NAMESTORE_zone_to_name (struct GNUNET_NAMESTORE_Handle *h,
359 const struct GNUNET_CRYPTO_EccPrivateKey *zone,
360 const struct GNUNET_CRYPTO_EccPublicKey *value_zone,
361 GNUNET_NAMESTORE_RecordMonitor proc, void *proc_cls);
365 * Cancel a namestore operation. The final callback from the
366 * operation must not have been done yet. Must be called on any
367 * namestore operation that has not yet completed prior to calling
368 * 'GNUNET_NAMESTORE_disconnect'.
370 * @param qe operation to cancel
373 GNUNET_NAMESTORE_cancel (struct GNUNET_NAMESTORE_QueueEntry *qe);
377 * Starts a new zone iteration (used to periodically PUT all of our
378 * records into our DHT). "proc" will be called once immediately, and
379 * then again after "GNUNET_NAMESTORE_zone_iterator_next" is invoked.
381 * @param h handle to the namestore
382 * @param zone zone to access
383 * @param must_have_flags flags that must be set for the record to be returned
384 * @param must_not_have_flags flags that must NOT be set for the record to be returned
385 * @param proc function to call on each name from the zone; it
386 * will be called repeatedly with a value (if available)
387 * and always once at the end with a name of NULL.
388 * @param proc_cls closure for proc
389 * @return an iterator handle to use for iteration
391 struct GNUNET_NAMESTORE_ZoneIterator *
392 GNUNET_NAMESTORE_zone_iteration_start (struct GNUNET_NAMESTORE_Handle *h,
393 const struct GNUNET_CRYPTO_EccPrivateKey *zone,
394 GNUNET_NAMESTORE_RecordMonitor proc,
399 * Calls the record processor specified in GNUNET_NAMESTORE_zone_iteration_start
400 * for the next record.
402 * @param it the iterator
405 GNUNET_NAMESTORE_zone_iterator_next (struct GNUNET_NAMESTORE_ZoneIterator *it);
409 * Stops iteration and releases the namestore handle for further calls. Must
410 * be called on any iteration that has not yet completed prior to calling
411 * 'GNUNET_NAMESTORE_disconnect'.
413 * @param it the iterator
416 GNUNET_NAMESTORE_zone_iteration_stop (struct GNUNET_NAMESTORE_ZoneIterator *it);
420 * Handle for a monitoring activity.
422 struct GNUNET_NAMESTORE_ZoneMonitor;
426 * Function called once the monitor has caught up with the current
427 * state of the database. Will be called AGAIN after each disconnect
428 * (record monitor called with 'NULL' for zone_key) once we're again
433 typedef void (*GNUNET_NAMESTORE_RecordsSynchronizedCallback)(void *cls);
437 * Begin monitoring a zone for changes. Will first call the 'monitor' function
438 * on all existing records in the selected zone(s), then calls 'sync_cb',
439 * and then calls the 'monitor' whenever a record changes. If the namestore
440 * disconnects, the 'monitor' function is called with a disconnect event; if
441 * the connection is re-established, the process begins from the start (all
442 * existing records, sync, then updates).
444 * Note that the 'signature' in the 'monitor' callback will always be
445 * NULL (as signatures are usually not valuable to monitoring clients,
446 * the service does not bother to generate a valid signature for
449 * @param cfg configuration to use to connect to namestore
450 * @param zone zone to monitor
451 * @param monitor function to call on zone changes
452 * @param sync_cb function called when we're in sync with the namestore
453 * @param cls closure for 'monitor' and 'sync_cb'
454 * @return handle to stop monitoring
456 struct GNUNET_NAMESTORE_ZoneMonitor *
457 GNUNET_NAMESTORE_zone_monitor_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
458 const struct GNUNET_CRYPTO_EccPrivateKey *zone,
459 GNUNET_NAMESTORE_RecordMonitor monitor,
460 GNUNET_NAMESTORE_RecordsSynchronizedCallback sync_cb,
465 * Stop monitoring a zone for changes.
467 * @param zm handle to the monitor activity to stop
470 GNUNET_NAMESTORE_zone_monitor_stop (struct GNUNET_NAMESTORE_ZoneMonitor *zm);
473 /* convenience APIs for serializing / deserializing GNS records */
476 * Calculate how many bytes we will need to serialize the given
479 * @param rd_count number of records in the rd array
480 * @param rd array of GNUNET_NAMESTORE_RecordData with rd_count elements
482 * @return the required size to serialize
486 GNUNET_NAMESTORE_records_get_size (unsigned int rd_count,
487 const struct GNUNET_NAMESTORE_RecordData *rd);
491 * Serialize the given records to the given destination buffer.
493 * @param rd_count number of records in the rd array
494 * @param rd array of GNUNET_NAMESTORE_RecordData with rd_count elements
495 * @param dest_size size of the destination array
496 * @param dest where to write the result
498 * @return the size of serialized records, -1 if records do not fit
501 GNUNET_NAMESTORE_records_serialize (unsigned int rd_count,
502 const struct GNUNET_NAMESTORE_RecordData *rd,
508 * Deserialize the given records to the given destination.
510 * @param len size of the serialized record data
511 * @param src the serialized record data
512 * @param rd_count number of records in the rd array
513 * @param dest where to put the data
515 * @return GNUNET_OK on success, GNUNET_SYSERR on error
518 GNUNET_NAMESTORE_records_deserialize (size_t len,
520 unsigned int rd_count,
521 struct GNUNET_NAMESTORE_RecordData *dest);
525 * Convert the 'value' of a record to a string.
527 * @param type type of the record
528 * @param data value in binary encoding
529 * @param data_size number of bytes in data
530 * @return NULL on error, otherwise human-readable representation of the value
533 GNUNET_NAMESTORE_value_to_string (uint32_t type,
539 * Convert human-readable version of a 'value' of a record to the binary
542 * @param type type of the record
543 * @param s human-readable string
544 * @param data set to value in binary encoding (will be allocated)
545 * @param data_size set to number of bytes in data
546 * @return GNUNET_OK on success
549 GNUNET_NAMESTORE_string_to_value (uint32_t type,
556 * Convert a type name (i.e. "AAAA") to the corresponding number.
558 * @param typename name to convert
559 * @return corresponding number, UINT32_MAX on error
562 GNUNET_NAMESTORE_typename_to_number (const char *typename);
566 * Convert a type number (i.e. 1) to the corresponding type string (i.e. "A")
568 * @param type number of a type to convert
569 * @return corresponding typestring, NULL on error
572 GNUNET_NAMESTORE_number_to_typename (uint32_t type);
576 * Test if a given record is expired.
578 * @param rd record to test
579 * @return GNUNET_YES if the record is expired,
583 GNUNET_NAMESTORE_is_expired (const struct GNUNET_NAMESTORE_RecordData *rd);
587 * Convert a UTF-8 string to UTF-8 lowercase
588 * @param src source string
589 * @return converted result
592 GNUNET_NAMESTORE_normalize_string (const char *src);
596 * Convert a zone to a string (for printing debug messages).
597 * This is one of the very few calls in the entire API that is
600 * @param z public key of a zone
601 * @return string form; will be overwritten by next call to GNUNET_h2s.
604 GNUNET_NAMESTORE_z2s (const struct GNUNET_CRYPTO_EccPublicKey *z);
608 * Calculate the DHT query for a given 'label' in a given zone.
610 * @param zone private key of the zone
611 * @param label label of the record
612 * @return query hash to use for the query
615 GNUNET_NAMESTORE_query_from_private_key (const struct GNUNET_CRYPTO_EccPrivateKey *zone,
617 struct GNUNET_HashCode *query);
621 * Calculate the DHT query for a given 'label' in a given zone.
623 * @param pub public key of the zone
624 * @param label label of the record
625 * @return query hash to use for the query
628 GNUNET_NAMESTORE_query_from_public_key (const struct GNUNET_CRYPTO_EccPublicKey *pub,
630 struct GNUNET_HashCode *query);
634 * Sign name and records
636 * @param key the private key
637 * @param expire block expiration
638 * @param label the name for the records
639 * @param rd record data
640 * @param rd_count number of records
641 * @param signature where to store the signature
643 struct GNUNET_NAMESTORE_Block *
644 GNUNET_NAMESTORE_block_create (const struct GNUNET_CRYPTO_EccPrivateKey *key,
645 struct GNUNET_TIME_Absolute expire,
647 const struct GNUNET_NAMESTORE_RecordData *rd,
648 unsigned int rd_count);
652 * Check if a signature is valid. This API is used by the GNS Block
653 * to validate signatures received from the network.
655 * @param block block to verify
656 * @return GNUNET_OK if the signature is valid
659 GNUNET_NAMESTORE_block_verify (const struct GNUNET_NAMESTORE_Block *block);
665 * @param block block to decrypt
666 * @param zone_key public key of the zone
667 * @param label the name for the records
668 * @param proc function to call with the result
669 * @param proc_cls closure for proc
670 * @param GNUNET_OK on success, GNUNET_SYSERR if the block was
674 GNUNET_NAMESTORE_block_decrypt (const struct GNUNET_NAMESTORE_Block *block,
675 const struct GNUNET_CRYPTO_EccPublicKey *zone_key,
677 GNUNET_NAMESTORE_RecordMonitor proc,
682 * Compares if two records are equal
687 * @return GNUNET_YES or GNUNET_NO
690 GNUNET_NAMESTORE_records_cmp (const struct GNUNET_NAMESTORE_RecordData *a,
691 const struct GNUNET_NAMESTORE_RecordData *b);
695 * Returns the expiration time of the given block of records. The block
696 * expiration time is the expiration time of the block with smallest
699 * @param rd_count number of records given in 'rd'
700 * @param rd array of records
701 * @return absolute expiration time
703 struct GNUNET_TIME_Absolute
704 GNUNET_NAMESTORE_record_get_expiration_time (unsigned int rd_count,
705 const struct GNUNET_NAMESTORE_RecordData *rd);
708 #if 0 /* keep Emacsens' auto-indent happy */
715 /* end of gnunet_namestore_service.h */