aboutsummaryrefslogtreecommitdiff
path: root/src/include/gnunet_psycstore_service.h
blob: fab2594df9d48359833748ebeb57d2d91eb35a9a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
/*
     This file is part of GNUnet.
     (C) 2013 Christian Grothoff (and other contributing authors)

     GNUnet is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published
     by the Free Software Foundation; either version 3, or (at your
     option) any later version.

     GNUnet is distributed in the hope that it will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/

/** 
 * @file include/gnunet_psycstore_service.h
 * @brief PSYCstore service; implements persistent storage for the PSYC service
 * @author Gabor X Toth
 * @author Christian Grothoff
 */
#ifndef GNUNET_PSYCSTORE_SERVICE_H
#define GNUNET_PSYCSTORE_SERVICE_H

#ifdef __cplusplus
extern "C"
{
#if 0                           /* keep Emacsens' auto-indent happy */
}
#endif
#endif

#include "gnunet_util_lib.h"
#include "gnunet_env_lib.h"
#include "gnunet_multicast_service.h"
#include "gnunet_psyc_service.h"

/** 
 * Version number of GNUnet PSYCstore API.
 */
#define GNUNET_PSYCSTORE_VERSION 0x00000000

/**
 * Flags for stored messages.
 */
enum GNUNET_PSYCSTORE_MessageFlags
{
  /**
   * The message contains state modifiers.
   */
  GNUNET_PSYCSTORE_MESSAGE_STATE = 1 << 0,

  /**
   * The state modifiers have been applied to the state store.
   */
  GNUNET_PSYCSTORE_MESSAGE_STATE_APPLIED = 1 << 1,

  /**
   * The message contains a state hash.
   */
  GNUNET_PSYCSTORE_MESSAGE_STATE_HASH = 1 << 2
};


/** 
 * Handle for a PSYCstore
 */
struct GNUNET_PSYCSTORE_Handle;


/** 
 * Connect to the PSYCstore service.
 *
 * @param cfg Configuration to use.
 *
 * @return Handle for the connecton.
 */
struct GNUNET_PSYCSTORE_Handle *
GNUNET_PSYCSTORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg);


/** 
 * Disconnect from the PSYCstore service.
 *
 * @param h Handle for the connection.
 */
void
GNUNET_PSYCSTORE_disconnect (struct GNUNET_PSYCSTORE_Handle *h);


/** 
 * Handle for an operation on the PSYCSTORE (useful to cancel the operation).
 */
struct GNUNET_PSYCSTORE_OperationHandle;


/** 
 * Function called with the result of an asynchronous operation.
 * 
 * @param result #GNUNET_SYSERR on error,
 *        #GNUNET_YES on success or if the peer was a member,
 *        #GNUNET_NO if the peer was not a member
 */
typedef void
(*GNUNET_PSYCSTORE_ResultCallback) (void *cls,
                                    int result,
                                    const char *err_msg);


/** 
 * Store join/leave events for a PSYC channel in order to be able to answer
 * membership test queries later.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key The channel where the event happened.
 * @param slave_key Public key of joining/leaving slave.
 * @param did_join #GNUNET_YES on join, #GNUNET_NO on part.
 * @param announced_at ID of the message that announced the membership change.
 * @param effective_since Message ID this membership change is in effect since.
 *        For joins it is <= announced_at, for parts it is always 0.
 * @param group_generation In case of a part, the last group generation the
 *        slave has access to.  It has relevance when a larger message have
 *        fragments with different group generations.
 * @param rcb Callback to call with the result of the storage operation.
 * @param rcb_cls Closure for the callback.
 *
 * @return Operation handle that can be used to cancel the operation.
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_membership_store (struct GNUNET_PSYCSTORE_Handle *h,
                                   const struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                                   const struct GNUNET_CRYPTO_EccPublicKey *slave_key,
                                   int did_join,
                                   uint64_t announced_at,
                                   uint64_t effective_since,
                                   uint64_t group_generation,
                                   GNUNET_PSYCSTORE_ResultCallback rcb,
                                   void *rcb_cls);


/** 
 * Test if a member was admitted to the channel at the given message ID.
 *
 * This is useful when relaying and replaying messages to check if a particular
 * slave has access to the message fragment with a given group generation.  It
 * is also used when handling join requests to determine whether the slave is
 * currently admitted to the channel.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key The channel we are interested in.
 * @param slave_key Public key of slave whose membership to check.
 * @param message_id Message ID for which to do the membership test.
 * @param group_generation Group generation of the fragment of the message to
 *        test.  It has relevance if the message consists of multiple fragments
 *        with different group generations.
 * @param rcb Callback to call with the test result.
 * @param rcb_cls Closure for the callback.
 *
 * @return Operation handle that can be used to cancel the operation.
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_membership_test (struct GNUNET_PSYCSTORE_Handle *h,
                                  const struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                                  const struct GNUNET_CRYPTO_EccPublicKey *slave_key,
                                  uint64_t message_id,
                                  uint64_t group_generation,
                                  GNUNET_PSYCSTORE_ResultCallback rcb,
                                  void *rcb_cls);


/** 
 * Store a message fragment sent to a channel.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key The channel the message belongs to.
 * @param message Message to store.
 * @param psycstore_flags Flags indicating whether the PSYC message contains
 *        state modifiers.
 * @param rcb Callback to call with the result of the operation.
 * @param rcb_cls Closure for the callback.
 * 
 * @return Handle that can be used to cancel the operation.
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_fragment_store (struct GNUNET_PSYCSTORE_Handle *h,
                                 const struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                                 const struct GNUNET_MULTICAST_MessageHeader *message,
                                 uint32_t psycstore_flags,
                                 GNUNET_PSYCSTORE_ResultCallback rcb,
                                 void *rcb_cls);


/** 
 * Function called with one message fragment, as the result of a
 * GNUNET_PSYCSTORE_fragment_get() or GNUNET_PSYCSTORE_message_get() call.
 *
 * @param cls Closure.
 * @param message The retrieved message fragment.  A NULL value indicates that
 *        there are no more results to be returned.
 * @param flags Flags stored with the message.
 *
 * @return #GNUNET_NO to stop calling this callback with further fragments,
 *         #GNUNET_YES to continue.
 */
typedef int
(*GNUNET_PSYCSTORE_FragmentCallback) (void *cls,
                                      struct GNUNET_MULTICAST_MessageHeader *message,
                                      enum GNUNET_PSYCSTORE_MessageFlags flags);


/** 
 * Retrieve a message fragment by fragment ID.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key The channel we are interested in.
 * @param fragment_id Fragment ID to check.  Use 0 to get the latest message fragment.
 * @param cb Callback to call with the retrieved fragment.
 * @param cb_cls Closure for the callback.
 * 
 * @return Handle that can be used to cancel the operation.
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_fragment_get (struct GNUNET_PSYCSTORE_Handle *h,
                               const struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                               uint64_t fragment_id,
                               GNUNET_PSYCSTORE_FragmentCallback cb,
                               void *cb_cls);


/** 
 * Retrieve all fragments of a message.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key The channel we are interested in.
 * @param message_id Message ID to check.  Use 0 to get the latest message.
 * @param cb Callback to call with the retrieved fragments.
 * @param cb_cls Closure for the callback.
 * 
 * @return Handle that can be used to cancel the operation.
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_message_get (struct GNUNET_PSYCSTORE_Handle *h,
                              const struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                              uint64_t message_id,
                              GNUNET_PSYCSTORE_FragmentCallback cb,
                              void *cb_cls);


/** 
 * Retrieve a fragment of message specified by its message ID and fragment
 * offset.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key The channel we are interested in.
 * @param message_id Message ID to check.  Use 0 to get the latest message.
 * @param fragment_offset Offset of the fragment to retrieve.
 * @param cb Callback to call with the retrieved fragments.
 * @param cb_cls Closure for the callback.
 * 
 * @return Handle that can be used to cancel the operation.
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_message_get_fragment (struct GNUNET_PSYCSTORE_Handle *h,
                                       const struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                                       uint64_t message_id,
                                       uint64_t fragment_offset,
                                       GNUNET_PSYCSTORE_FragmentCallback cb,
                                       void *cb_cls);


/** 
 * Callback used to return the latest value of counters for the channel master.
 *
 * @see GNUNET_PSYCSTORE_counters_get_master()
 *
 * @param cls Closure.
 * @param fragment_id Latest message fragment ID, used by multicast.
 * @param message_id Latest message ID, used by PSYC.
 * @param group_generation Latest group generation, used by PSYC.
 */
typedef void
(*GNUNET_PSYCSTORE_MasterCountersCallback) (void *cls,
                                            uint64_t fragment_id,
                                            uint64_t message_id,
                                            uint64_t group_generation);


/** 
 * Callback used to return the latest value of counters for a channel slave.
 *
 * @see GNUNET_PSYCSTORE_counters_get_slave()
 *
 * @param cls Closure.
 * @param max_state_msg_id Latest message ID containing state modifiers that was
 *        applied to the state store.  Used for the state sync process.
 */
typedef void
(*GNUNET_PSYCSTORE_SlaveCountersCallback) (void *cls,
                                           uint64_t max_state_msg_id);


/** 
 * Retrieve latest values of counters for a channel master.
 *
 * The current value of counters are needed when a channel master is restarted,
 * so that it can continue incrementing the counters from their last value.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key Public key that identifies the channel.
 * @param cb Callback to call with the result.
 * @param cb_cls Closure for the callback.
 * 
 * @return 
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_counters_get_master (struct GNUNET_PSYCSTORE_Handle *h,
                                      struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                                      GNUNET_PSYCSTORE_MasterCountersCallback *cb,
                                      void *cb_cls);


/** 
 * Retrieve latest values of counters for a channel slave.
 *
 * The current value of counters are needed when a channel slave rejoins
 * and starts the state synchronization process.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key Public key that identifies the channel.
 * @param cb Callback to call with the result.
 * @param cb_cls Closure for the callback.
 * 
 * @return 
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_counters_get_slave (struct GNUNET_PSYCSTORE_Handle *h,
                                     struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                                     GNUNET_PSYCSTORE_SlaveCountersCallback *cb,
                                     void *cb_cls);


/** 
 * Apply modifiers of a message to the current channel state.
 *
 * An error is returned if there are missing messages containing state
 * operations before the current one.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key The channel we are interested in.
 * @param message_id ID of the message that contains the @a modifiers.
 * @param state_delta Value of the _state_delta PSYC header variable of the message.
 * @param modifier_count Number of elements in the @a modifiers array.
 * @param modifiers List of modifiers to apply.
 * @param rcb Callback to call with the result of the operation.
 * @param rcb_cls Closure for the callback.
 * 
 * @return Handle that can be used to cancel the operation.
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_state_modify (struct GNUNET_PSYCSTORE_Handle *h,
                               const struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                               uint64_t message_id,
                               uint64_t state_delta,
                               size_t modifier_count,
                               const struct GNUNET_ENV_Modifier *modifiers,
                               GNUNET_PSYCSTORE_ResultCallback rcb,
                               void *rcb_cls);


/** 
 * Reset the state of a channel.
 *
 * Delete all state variables stored for the given channel.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key The channel we are interested in.
 * @param rcb Callback to call with the result of the operation.
 * @param rcb_cls Closure for the callback.
 * 
 * @return Handle that can be used to cancel the operation.
 */
struct GNUNET_PSYCSTORE_Handle *
GNUNET_PSYCSTORE_state_reset (struct GNUNET_PSYCSTORE_Handle *h,
                              const struct GNUNET_CRYPTO_EccPublicKey
                              *channel_key,
                              GNUNET_PSYCSTORE_ResultCallback rcb,
                              void *rcb_cls);


/** 
 * Update signed values of state variables in the state store.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key The channel we are interested in.
 * @param message_id Message ID that contained the state @a hash.
 * @param hash Hash of the serialized full state.
 * @param rcb Callback to call with the result of the operation.
 * @param rcb_cls Closure for the callback.
 *
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_state_hash_update (struct GNUNET_PSYCSTORE_Handle *h,
                                    const struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                                    uint64_t message_id,
                                    const struct GNUNET_HashCode *hash,
                                    GNUNET_PSYCSTORE_ResultCallback rcb,
                                    void *rcb_cls);


/** 
 * Function called with the value of a state variable.
 *
 * @param cls Closure.
 * @param name Name of the state variable.  A NULL value indicates that there are no more
 *        state variables to be returned.
 * @param value Value of the state variable.
 * @param value_size Number of bytes in @a value.
 *
 * @return #GNUNET_NO to stop calling this callback with further variables,
 *         #GNUNET_YES to continue.
 */
typedef int
(*GNUNET_PSYCSTORE_StateCallback) (void *cls,
                                   const char *name,
                                   const void *value,
                                   size_t value_size);


/** 
 * Retrieve the best matching state variable.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key The channel we are interested in.
 * @param name Name of variable to match, the returned variable might be less specific.
 * @param cb Callback to return matching state variables.
 * @param cb_cls Closure for the callback.
 * 
 * @return Handle that can be used to cancel the operation.
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_state_get (struct GNUNET_PSYCSTORE_Handle *h,
                            const struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                            const char *name,
                            GNUNET_PSYCSTORE_StateCallback cb,
                            void *cb_cls);


/** 
 * Retrieve all state variables for a channel with the given prefix.
 *
 * @param h Handle for the PSYCstore.
 * @param channel_key The channel we are interested in.
 * @param name_prefix Prefix of state variable names to match.
 * @param cb Callback to return matching state variables.
 * @param cb_cls Closure for the callback.
 * 
 * @return Handle that can be used to cancel the operation.
 */
struct GNUNET_PSYCSTORE_OperationHandle *
GNUNET_PSYCSTORE_state_get_all (struct GNUNET_PSYCSTORE_Handle *h,
                                const struct GNUNET_CRYPTO_EccPublicKey *channel_key,
                                const char *name_prefix,
                                GNUNET_PSYCSTORE_StateCallback cb,
                                void *cb_cls);


/** 
 * Cancel an operation.
 *
 * @param op Handle for the operation to cancel.
 */
void
GNUNET_PSYCSTORE_operation_cancel (struct GNUNET_PSYCSTORE_OperationHandle *op);




#if 0                           /* keep Emacsens' auto-indent happy */
{
#endif
#ifdef __cplusplus
}
#endif

/* ifndef GNUNET_PSYCSTORE_SERVICE_H */
#endif
/* end of gnunet_psycstore_service.h */