2 This file is part of GNUnet
3 Copyright (C) 2012, 2013, 2018 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 * API that can be used to store naming information on a GNUnet node;
27 * @defgroup namestore Name Store service
28 * Store naming information on a GNUnet node.
30 * Naming information can either be records for which this peer/user is
31 * authoritative, or blocks which are cached, encrypted naming data from other
34 * @see [Documentation](https://gnunet.org/namestore-subsystem)
38 #ifndef GNUNET_NAMESTORE_SERVICE_H
39 #define GNUNET_NAMESTORE_SERVICE_H
41 #include "gnunet_util_lib.h"
42 #include "gnunet_block_lib.h"
43 #include "gnunet_gnsrecord_lib.h"
48 #if 0 /* keep Emacsens' auto-indent happy */
57 struct GNUNET_NAMESTORE_QueueEntry;
60 * Handle to the namestore service.
62 struct GNUNET_NAMESTORE_Handle;
65 * Handle to the namestore zone iterator.
67 struct GNUNET_NAMESTORE_ZoneIterator;
71 * Connect to the namestore service.
73 * @param cfg configuration to use
74 * @return handle to use to access the service
76 struct GNUNET_NAMESTORE_Handle *
77 GNUNET_NAMESTORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg);
81 * Disconnect from the namestore service (and free associated
82 * resources). Must not be called from within operation callbacks of
85 * @param h handle to the namestore
88 GNUNET_NAMESTORE_disconnect (struct GNUNET_NAMESTORE_Handle *h);
92 * Continuation called to notify client about result of the
96 * @param success #GNUNET_SYSERR on failure (including timeout/queue drop/failure to validate)
97 * #GNUNET_NO if content was already there or not found
98 * #GNUNET_YES (or other positive value) on success
99 * @param emsg NULL on success, otherwise an error message
102 (*GNUNET_NAMESTORE_ContinuationWithStatus) (void *cls,
108 * Store an item in the namestore. If the item is already present,
109 * it is replaced with the new record. Use an empty array to
110 * remove all records under the given name.
112 * The continuation is called after the value has been stored in the
113 * database. Monitors may be notified asynchronously (basically with
114 * a buffer). However, if any monitor is consistently too slow to
115 * keep up with the changes, calling @a cont will be delayed until the
116 * monitors do keep up.
118 * @param h handle to the namestore
119 * @param pkey private key of the zone
120 * @param label name that is being mapped
121 * @param rd_count number of records in the 'rd' array
122 * @param rd array of records with data to store
123 * @param cont continuation to call when done
124 * @param cont_cls closure for @a cont
125 * @return handle to abort the request
127 struct GNUNET_NAMESTORE_QueueEntry *
128 GNUNET_NAMESTORE_records_store (struct GNUNET_NAMESTORE_Handle *h,
130 GNUNET_CRYPTO_EcdsaPrivateKey *pkey,
132 unsigned int rd_count,
133 const struct GNUNET_GNSRECORD_Data *rd,
134 GNUNET_NAMESTORE_ContinuationWithStatus cont,
139 * Process a record that was stored in the namestore.
142 * @param zone private key of the zone
143 * @param label label of the records
144 * @param rd_count number of entries in @a rd array, 0 if label was deleted
145 * @param rd array of records with data to store
148 (*GNUNET_NAMESTORE_RecordMonitor) (void *cls,
150 GNUNET_CRYPTO_EcdsaPrivateKey *zone,
152 unsigned int rd_count,
153 const struct GNUNET_GNSRECORD_Data *rd);
157 * Lookup an item in the namestore.
159 * @param h handle to the namestore
160 * @param pkey private key of the zone
161 * @param label name that is being mapped
162 * @param error_cb function to call on error (i.e. disconnect)
163 * the handle is afterwards invalid
164 * @param error_cb_cls closure for @a error_cb
165 * @param rm function to call with the result (with 0 records if we don't have that label);
166 * the handle is afterwards invalid
167 * @param rm_cls closure for @a rm
168 * @return handle to abort the request
170 struct GNUNET_NAMESTORE_QueueEntry *
171 GNUNET_NAMESTORE_records_lookup (struct GNUNET_NAMESTORE_Handle *h,
173 GNUNET_CRYPTO_EcdsaPrivateKey *pkey,
175 GNUNET_SCHEDULER_TaskCallback error_cb,
177 GNUNET_NAMESTORE_RecordMonitor rm,
182 * Look for an existing PKEY delegation record for a given public key.
183 * Returns at most one result to the processor.
185 * @param h handle to the namestore
186 * @param zone private key of the zone to look up in, never NULL
187 * @param value_zone public key of the target zone (value), never NULL
188 * @param error_cb function to call on error (i.e. disconnect)
189 * the handle is afterwards invalid
190 * @param error_cb_cls closure for @a error_cb
191 * @param proc function to call on the matching records, or with
192 * NULL (rd_count == 0) if there are no matching records;
193 * the handle is afterwards invalid
194 * @param proc_cls closure for @a proc
195 * @return a handle that can be used to
198 struct GNUNET_NAMESTORE_QueueEntry *
199 GNUNET_NAMESTORE_zone_to_name (struct GNUNET_NAMESTORE_Handle *h,
200 const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone,
202 GNUNET_CRYPTO_EcdsaPublicKey *value_zone,
203 GNUNET_SCHEDULER_TaskCallback error_cb,
205 GNUNET_NAMESTORE_RecordMonitor proc,
210 * Cancel a namestore operation. The final callback from the
211 * operation must not have been done yet. Must be called on any
212 * namestore operation that has not yet completed prior to calling
213 * #GNUNET_NAMESTORE_disconnect.
215 * @param qe operation to cancel
218 GNUNET_NAMESTORE_cancel (struct GNUNET_NAMESTORE_QueueEntry *qe);
222 * Starts a new zone iteration (used to periodically PUT all of our
223 * records into our DHT). This MUST lock the `struct GNUNET_NAMESTORE_Handle`
224 * for any other calls than #GNUNET_NAMESTORE_zone_iterator_next() and
225 * #GNUNET_NAMESTORE_zone_iteration_stop. @a proc will be called once
226 * immediately, and then again after
227 * #GNUNET_NAMESTORE_zone_iterator_next() is invoked.
229 * On error (disconnect), @a error_cb will be invoked.
230 * On normal completion, @a finish_cb proc will be
233 * @param h handle to the namestore
234 * @param zone zone to access, NULL for all zones
235 * @param error_cb function to call on error (i.e. disconnect),
236 * the handle is afterwards invalid
237 * @param error_cb_cls closure for @a error_cb
238 * @param proc function to call on each name from the zone; it
239 * will be called repeatedly with a value (if available)
240 * @param proc_cls closure for @a proc
241 * @param finish_cb function to call on completion
242 * the handle is afterwards invalid
243 * @param finish_cb_cls closure for @a finish_cb
244 * @return an iterator handle to use for iteration
246 struct GNUNET_NAMESTORE_ZoneIterator *
247 GNUNET_NAMESTORE_zone_iteration_start (struct GNUNET_NAMESTORE_Handle *h,
249 GNUNET_CRYPTO_EcdsaPrivateKey *zone,
250 GNUNET_SCHEDULER_TaskCallback error_cb,
252 GNUNET_NAMESTORE_RecordMonitor proc,
254 GNUNET_SCHEDULER_TaskCallback finish_cb,
255 void *finish_cb_cls);
259 * Calls the record processor specified in #GNUNET_NAMESTORE_zone_iteration_start
260 * for the next record.
262 * @param it the iterator
263 * @param limit number of records to return to the iterator in one shot
264 * (before #GNUNET_NAMESTORE_zone_iterator_next is to be called again)
267 GNUNET_NAMESTORE_zone_iterator_next (struct GNUNET_NAMESTORE_ZoneIterator *it,
272 * Stops iteration and releases the namestore handle for further calls. Must
273 * be called on any iteration that has not yet completed prior to calling
274 * #GNUNET_NAMESTORE_disconnect.
276 * @param it the iterator
279 GNUNET_NAMESTORE_zone_iteration_stop (struct GNUNET_NAMESTORE_ZoneIterator *it);
283 * Handle for a monitoring activity.
285 struct GNUNET_NAMESTORE_ZoneMonitor;
289 * Begin monitoring a zone for changes. Will first call the @a
290 * monitor function on all existing records in the selected zone(s) if
291 * @a iterate_first is #GNUNET_YES. In any case, we will then call @a
292 * sync_cb, and then afterwards call the @a monitor whenever a record
293 * changes. If the namestore disconnects, the @a error_cb function is
294 * called with a disconnect event. Once the connection is
295 * re-established, the process begins from the start (depending on @a
296 * iterate_first, we will again first do all existing records, then @a
297 * sync, then updates).
299 * @param cfg configuration to use to connect to namestore
300 * @param zone zone to monitor, NULL for all zones
301 * @param iterate_first #GNUNET_YES to first iterate over all existing records,
302 * #GNUNET_NO to only return changes that happen from now on
303 * @param error_cb function to call on error (i.e. disconnect); note that
304 * unlike the other error callbacks in this API, a call to this
305 * function does NOT destroy the monitor handle, it merely signals
306 * that monitoring is down. You need to still explicitly call
307 * #GNUNET_NAMESTORE_zone_monitor_stop().
308 * @param error_cb_cls closure for @a error_cb
309 * @param monitor function to call on zone changes, with an initial limit of 1
310 * @param monitor_cls closure for @a monitor
311 * @param sync_cb function called when we're in sync with the namestore
312 * @param sync_cb_cls closure for @a sync_cb
313 * @return handle to stop monitoring
315 struct GNUNET_NAMESTORE_ZoneMonitor *
316 GNUNET_NAMESTORE_zone_monitor_start (const struct
317 GNUNET_CONFIGURATION_Handle *cfg,
319 GNUNET_CRYPTO_EcdsaPrivateKey *zone,
321 GNUNET_SCHEDULER_TaskCallback error_cb,
323 GNUNET_NAMESTORE_RecordMonitor monitor,
325 GNUNET_SCHEDULER_TaskCallback sync_cb,
330 * Calls the monitor processor specified in #GNUNET_NAMESTORE_zone_monitor_start
331 * for the next record(s). This function is used to allow clients that merely
332 * monitor the NAMESTORE to still throttle namestore operations, so we can be
333 * sure that the monitors can keep up.
335 * Note that #GNUNET_NAMESTORE_records_store() only waits for this
336 * call if the previous limit set by the client was already reached.
337 * Thus, by using a @a limit greater than 1, monitors basically enable
338 * a queue of notifications to be processed asynchronously with some
339 * delay. Note that even with a limit of 1 the
340 * #GNUNET_NAMESTORE_records_store() function will run asynchronously
341 * and the continuation may be invoked before the monitors completed
342 * (or even started) processing the notification. Thus, monitors will
343 * only closely track the current state of the namestore, but not
344 * be involved in the transactions.
346 * @param zm the monitor
347 * @param limit number of records to return to the iterator in one shot
348 * (before #GNUNET_NAMESTORE_zone_monitor_next is to be called again)
351 GNUNET_NAMESTORE_zone_monitor_next (struct GNUNET_NAMESTORE_ZoneMonitor *zm,
356 * Stop monitoring a zone for changes.
358 * @param zm handle to the monitor activity to stop
361 GNUNET_NAMESTORE_zone_monitor_stop (struct GNUNET_NAMESTORE_ZoneMonitor *zm);
364 #if 0 /* keep Emacsens' auto-indent happy */
373 /** @} */ /* end of group */