aboutsummaryrefslogtreecommitdiff
path: root/src/namestore/plugin_namestore_postgres.c
blob: 76c59ba0b82dcb6bc0a173c6d574921165fc762e (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
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
 /*
  * This file is part of GNUnet
  * Copyright (C) 2009-2013 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., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */

/**
 * @file namestore/plugin_namestore_postgres.c
 * @brief postgres-based namestore backend
 * @author Christian Grothoff
 */
#include "platform.h"
#include "gnunet_namestore_plugin.h"
#include "gnunet_namestore_service.h"
#include "gnunet_gnsrecord_lib.h"
#include "gnunet_postgres_lib.h"
#include "namestore.h"


/**
 * After how many ms "busy" should a DB operation fail for good?
 * A low value makes sure that we are more responsive to requests
 * (especially PUTs).  A high value guarantees a higher success
 * rate (SELECTs in iterate can take several seconds despite LIMIT=1).
 *
 * The default value of 1s should ensure that users do not experience
 * huge latencies while at the same time allowing operations to succeed
 * with reasonable probability.
 */
#define BUSY_TIMEOUT_MS 1000


/**
 * Log an error message at log-level 'level' that indicates
 * a failure of the command 'cmd' on file 'filename'
 * with the message given by strerror(errno).
 */
#define LOG_POSTGRES(db, level, cmd) do { GNUNET_log_from (level, "namestore-postgres", _("`%s' failed at %s:%d with error: %s\n"), cmd, __FILE__, __LINE__, sqlite3_errmsg(db->dbh)); } while(0)

#define LOG(kind,...) GNUNET_log_from (kind, "namestore-postgres", __VA_ARGS__)


/**
 * Context for all functions in this plugin.
 */
struct Plugin
{

  /**
   * Our configuration.
   */
  const struct GNUNET_CONFIGURATION_Handle *cfg;

  /**
   * Native Postgres database handle.
   */
  PGconn *dbh;

};


/**
 * Create our database indices.
 *
 * @param dbh handle to the database
 */
static void
create_indices (PGconn * dbh)
{
  /* create indices */
  if ( (GNUNET_OK !=
	GNUNET_POSTGRES_exec (dbh,
                              "CREATE INDEX ir_pkey_reverse ON ns097records (zone_private_key,pkey)")) ||
       (GNUNET_OK !=
	GNUNET_POSTGRES_exec (dbh,
                              "CREATE INDEX ir_pkey_iter ON ns097records (zone_private_key,rvalue)")) ||
       (GNUNET_OK !=
	GNUNET_POSTGRES_exec (dbh, "CREATE INDEX it_iter ON ns097records (rvalue)")) ||
       (GNUNET_OK !=
        GNUNET_POSTGRES_exec (dbh, "CREATE INDEX ir_label ON ns097records (label)")) )
    LOG (GNUNET_ERROR_TYPE_ERROR,
	 _("Failed to create indices\n"));
}


/**
 * Initialize the database connections and associated
 * data structures (create tables and indices
 * as needed as well).
 *
 * @param plugin the plugin context (state for this module)
 * @return #GNUNET_OK on success
 */
static int
database_setup (struct Plugin *plugin)
{
  PGresult *res;

  plugin->dbh = GNUNET_POSTGRES_connect (plugin->cfg,
					 "namestore-postgres");
  if (NULL == plugin->dbh)
    return GNUNET_SYSERR;
  if (GNUNET_YES ==
      GNUNET_CONFIGURATION_get_value_yesno (plugin->cfg,
					    "namestore-postgres",
					    "TEMPORARY_TABLE"))
  {
    res =
      PQexec (plugin->dbh,
              "CREATE TEMPORARY TABLE ns097records ("
	      " zone_private_key BYTEA NOT NULL DEFAULT '',"
	      " pkey BYTEA DEFAULT '',"
	      " rvalue BYTEA NOT NULL DEFAULT '',"
	      " record_count INTEGER NOT NULL DEFAULT 0,"
	      " record_data BYTEA NOT NULL DEFAULT '',"
	      " label TEXT NOT NULL DEFAULT ''"
	      ")" "WITH OIDS");
  }
  else
  {
    res =
      PQexec (plugin->dbh,
              "CREATE TABLE ns097records ("
	      " zone_private_key BYTEA NOT NULL DEFAULT '',"
	      " pkey BYTEA DEFAULT '',"
	      " rvalue BYTEA NOT NULL DEFAULT '',"
	      " record_count INTEGER NOT NULL DEFAULT 0,"
	      " record_data BYTEA NOT NULL DEFAULT '',"
	      " label TEXT NOT NULL DEFAULT ''"
	      ")" "WITH OIDS");
  }
  if ( (NULL == res) ||
       ((PQresultStatus (res) != PGRES_COMMAND_OK) &&
        (0 != strcmp ("42P07",    /* duplicate table */
                      PQresultErrorField
                      (res,
                       PG_DIAG_SQLSTATE)))))
  {
    (void) GNUNET_POSTGRES_check_result (plugin->dbh, res,
                                         PGRES_COMMAND_OK, "CREATE TABLE",
					 "ns097records");
    PQfinish (plugin->dbh);
    plugin->dbh = NULL;
    return GNUNET_SYSERR;
  }
  create_indices (plugin->dbh);

  if ((GNUNET_OK !=
       GNUNET_POSTGRES_prepare (plugin->dbh,
				"store_records",
				"INSERT INTO ns097records (zone_private_key, pkey, rvalue, record_count, record_data, label) VALUES "
                                "($1, $2, $3, $4, $5, $6)", 6)) ||
      (GNUNET_OK !=
       GNUNET_POSTGRES_prepare (plugin->dbh,
				"delete_records",
				"DELETE FROM ns097records WHERE zone_private_key=$1 AND label=$2", 2)) ||
      (GNUNET_OK !=
       GNUNET_POSTGRES_prepare (plugin->dbh,
				"zone_to_name",
				"SELECT record_count,record_data,label FROM ns097records"
                                " WHERE zone_private_key=$1 AND pkey=$2", 2)) ||
      (GNUNET_OK !=
       GNUNET_POSTGRES_prepare (plugin->dbh,
				"iterate_zone",
				"SELECT record_count,record_data,label FROM ns097records"
                                " WHERE zone_private_key=$1 ORDER BY rvalue LIMIT 1 OFFSET $2", 2)) ||
      (GNUNET_OK !=
       GNUNET_POSTGRES_prepare (plugin->dbh,
				"iterate_all_zones",
				"SELECT record_count,record_data,label,zone_private_key"
				" FROM ns097records ORDER BY rvalue LIMIT 1 OFFSET $1", 1)) ||
      (GNUNET_OK !=
       GNUNET_POSTGRES_prepare (plugin->dbh,
                                "lookup_label",
                                "SELECT record_count,record_data,label"
                                " FROM ns097records WHERE zone_private_key=$1 AND label=$2", 2)))
  {
    PQfinish (plugin->dbh);
    plugin->dbh = NULL;
    return GNUNET_SYSERR;
  }
  return GNUNET_OK;
}


/**
 * Store a record in the datastore.  Removes any existing record in the
 * same zone with the same name.
 *
 * @param cls closure (internal context for the plugin)
 * @param zone_key private key of the zone
 * @param label name that is being mapped (at most 255 characters long)
 * @param rd_count number of entries in @a rd array
 * @param rd array of records with data to store
 * @return #GNUNET_OK on success, else #GNUNET_SYSERR
 */
static int
namestore_postgres_store_records (void *cls,
                                  const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone_key,
                                  const char *label,
                                  unsigned int rd_count,
                                  const struct GNUNET_GNSRECORD_Data *rd)
{
  struct Plugin *plugin = cls;
  struct GNUNET_CRYPTO_EcdsaPublicKey pkey;
  uint64_t rvalue;
  uint32_t rd_count_nbo = htonl ((uint32_t) rd_count);
  size_t data_size;
  unsigned int i;

  memset (&pkey, 0, sizeof (pkey));
  for (i=0;i<rd_count;i++)
    if (GNUNET_GNSRECORD_TYPE_PKEY == rd[i].record_type)
    {
      GNUNET_break (sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey) == rd[i].data_size);
      memcpy (&pkey,
              rd[i].data,
              rd[i].data_size);
      break;
    }
  rvalue = GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK, UINT64_MAX);
  data_size = GNUNET_GNSRECORD_records_get_size (rd_count, rd);
  if (data_size > 64 * 65536)
  {
    GNUNET_break (0);
    return GNUNET_SYSERR;
  }
  {
    char data[data_size];
    const char *paramValues[] = {
      (const char *) zone_key,
      (const char *) &pkey,
      (const char *) &rvalue,
      (const char *) &rd_count_nbo,
      (const char *) data,
      label
    };
    int paramLengths[] = {
      sizeof (*zone_key),
      sizeof (pkey),
      sizeof (rvalue),
      sizeof (rd_count_nbo),
      data_size,
      strlen (label)
    };
    const int paramFormats[] = { 1, 1, 1, 1, 1, 1 };
    PGresult *res;

    if (data_size != GNUNET_GNSRECORD_records_serialize (rd_count, rd,
							 data_size, data))
    {
      GNUNET_break (0);
      return GNUNET_SYSERR;
    }

    res =
      PQexecPrepared (plugin->dbh, "store_records", 6,
                      paramValues, paramLengths, paramFormats, 1);
    if (GNUNET_OK !=
        GNUNET_POSTGRES_check_result (plugin->dbh,
                                      res,
                                      PGRES_COMMAND_OK,
                                      "PQexecPrepared",
                                      "store_records"))
      return GNUNET_SYSERR;
    PQclear (res);
    return GNUNET_OK;
  }
}


/**
 * A statement has been run.  We should evaluate the result, and if possible
 * call the given @a iter with the result.
 *
 * @param plugin plugin context
 * @param res result from the statement that was run (to be cleaned up)
 * @param zone_key private key of the zone, could be NULL, in which case we should
 *        get the zone from @a res
 * @param iter iterator to call with the result
 * @param iter_cls closure for @a iter
 * @return #GNUNET_OK on success, #GNUNET_NO if there were no results, #GNUNET_SYSERR on error
 */
static int
get_record_and_call_iterator (struct Plugin *plugin,
                              PGresult *res,
			      const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone_key,
			      GNUNET_NAMESTORE_RecordIterator iter, void *iter_cls)
{
  const char *data;
  size_t data_size;
  uint32_t record_count;
  const char *label;
  size_t label_len;
  unsigned int cnt;

  if (GNUNET_OK !=
      GNUNET_POSTGRES_check_result (plugin->dbh, res, PGRES_TUPLES_OK,
                                    "PQexecPrepared",
				    "iteration"))
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG,
	 "Failing lookup (postgres error)\n");
    return GNUNET_SYSERR;
  }
  if (0 == (cnt = PQntuples (res)))
  {
    /* no result */
    LOG (GNUNET_ERROR_TYPE_DEBUG,
	 "Ending iteration (no more results)\n");
    PQclear (res);
    return GNUNET_NO;
  }
  GNUNET_assert (1 == cnt);
  GNUNET_assert (3 + ((NULL == zone_key) ? 1 : 0) == PQnfields (res));
  if (NULL == zone_key)
  {
    if (sizeof (struct GNUNET_CRYPTO_EcdsaPrivateKey) != PQgetlength (res, 0, 3))
    {
      GNUNET_break (0);
      PQclear (res);
      return GNUNET_SYSERR;
    }
    zone_key = (const struct GNUNET_CRYPTO_EcdsaPrivateKey *) PQgetvalue (res, 0, 3);
  }
  if (sizeof (uint32_t) != PQfsize (res, 0))
  {
    GNUNET_break (0);
    PQclear (res);
    return GNUNET_SYSERR;
  }

  record_count = ntohl (*(uint32_t *) PQgetvalue (res, 0, 0));
  data = PQgetvalue (res, 0, 1);
  data_size = PQgetlength (res, 0, 1);
  label = PQgetvalue (res, 0, 2);
  label_len = PQgetlength (res, 0, 1);
  if (record_count > 64 * 1024)
  {
    /* sanity check, don't stack allocate far too much just
       because database might contain a large value here */
    GNUNET_break (0);
    PQclear (res);
    return GNUNET_SYSERR;
  }
  {
    struct GNUNET_GNSRECORD_Data rd[record_count];
    char buf[label_len + 1];

    memcpy (buf, label, label_len);
    buf[label_len] = '\0';
    if (GNUNET_OK !=
	GNUNET_GNSRECORD_records_deserialize (data_size, data,
					      record_count, rd))
    {
      GNUNET_break (0);
      PQclear (res);
      return GNUNET_SYSERR;
    }
    iter (iter_cls, zone_key, buf, record_count, rd);
  }
  PQclear (res);
  return GNUNET_OK;
}


/**
 * Lookup records in the datastore for which we are the authority.
 *
 * @param cls closure (internal context for the plugin)
 * @param zone private key of the zone
 * @param label name of the record in the zone
 * @param iter function to call with the result
 * @param iter_cls closure for @a iter
 * @return #GNUNET_OK on success, else #GNUNET_SYSERR
 */
static int
namestore_postgres_lookup_records (void *cls,
                                   const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone,
                                   const char *label,
                                   GNUNET_NAMESTORE_RecordIterator iter,
                                   void *iter_cls)
{
  struct Plugin *plugin = cls;
  const char *paramValues[] = {
    (const char *) zone,
    label
  };
  int paramLengths[] = {
    sizeof (*zone),
    strlen (label)
  };
  const int paramFormats[] = { 1, 1 };
  PGresult *res;

  res = PQexecPrepared (plugin->dbh,
                        "lookup_label", 2,
                        paramValues, paramLengths, paramFormats,
                        1);
  return get_record_and_call_iterator (plugin,
                                       res,
                                       zone,
                                       iter, iter_cls);
}


/**
 * Iterate over the results for a particular key and zone in the
 * datastore.  Will return at most one result to the iterator.
 *
 * @param cls closure (internal context for the plugin)
 * @param zone hash of public key of the zone, NULL to iterate over all zones
 * @param offset offset in the list of all matching records
 * @param iter function to call with the result
 * @param iter_cls closure for @a iter
 * @return #GNUNET_OK on success, #GNUNET_NO if there were no results, #GNUNET_SYSERR on error
 */
static int
namestore_postgres_iterate_records (void *cls,
                                    const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone,
                                    uint64_t offset,
                                    GNUNET_NAMESTORE_RecordIterator iter, void *iter_cls)
{
  struct Plugin *plugin = cls;
  uint64_t offset_be = GNUNET_htonll (offset);

  if (NULL == zone)
  {
    const char *paramValues[] = {
      (const char *) &offset_be
    };
    int paramLengths[] = {
      sizeof (offset_be)
    };
    const int paramFormats[] = { 1 };
    PGresult *res;

    res = PQexecPrepared (plugin->dbh,
                          "iterate_all_zones", 1,
                          paramValues, paramLengths, paramFormats,
                          1);
    return get_record_and_call_iterator (plugin,
                                         res,
                                         NULL,
                                         iter, iter_cls);
  }
  else
  {
    const char *paramValues[] = {
      (const char *) zone,
      (const char *) &offset_be
    };
    int paramLengths[] = {
      sizeof (*zone),
      sizeof (offset_be)
    };
    const int paramFormats[] = { 1, 1 };
    PGresult *res;

    res = PQexecPrepared (plugin->dbh,
                          "iterate_zone", 2,
                          paramValues, paramLengths, paramFormats,
                          1);
    return get_record_and_call_iterator (plugin,
                                         res,
                                         zone,
                                         iter, iter_cls);
  }
}


/**
 * Look for an existing PKEY delegation record for a given public key.
 * Returns at most one result to the iterator.
 *
 * @param cls closure (internal context for the plugin)
 * @param zone private key of the zone to look up in, never NULL
 * @param value_zone public key of the target zone (value), never NULL
 * @param iter function to call with the result
 * @param iter_cls closure for @a iter
 * @return #GNUNET_OK on success, #GNUNET_NO if there were no results, #GNUNET_SYSERR on error
 */
static int
namestore_postgres_zone_to_name (void *cls,
                                 const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone,
                                 const struct GNUNET_CRYPTO_EcdsaPublicKey *value_zone,
                                 GNUNET_NAMESTORE_RecordIterator iter, void *iter_cls)
{
  struct Plugin *plugin = cls;
  const char *paramValues[] = {
    (const char *) zone,
    (const char *) value_zone
  };
  int paramLengths[] = {
    sizeof (*zone),
    sizeof (*value_zone)
  };
  const int paramFormats[] = { 1, 1 };
  PGresult *res;

  res = PQexecPrepared (plugin->dbh,
                        "zone_to_name", 2,
                        paramValues, paramLengths, paramFormats,
                        1);
  return get_record_and_call_iterator (plugin,
                                       res,
                                       zone,
                                       iter, iter_cls);
}


/**
 * Shutdown database connection and associate data
 * structures.
 *
 * @param plugin the plugin context (state for this module)
 */
static void
database_shutdown (struct Plugin *plugin)
{
  PQfinish (plugin->dbh);
  plugin->dbh = NULL;
}


/**
 * Entry point for the plugin.
 *
 * @param cls the `struct GNUNET_NAMESTORE_PluginEnvironment*`
 * @return NULL on error, othrewise the plugin context
 */
void *
libgnunet_plugin_namestore_postgres_init (void *cls)
{
  static struct Plugin plugin;
  const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
  struct GNUNET_NAMESTORE_PluginFunctions *api;

  if (NULL != plugin.cfg)
    return NULL;                /* can only initialize once! */
  memset (&plugin, 0, sizeof (struct Plugin));
  plugin.cfg = cfg;
  if (GNUNET_OK != database_setup (&plugin))
  {
    database_shutdown (&plugin);
    return NULL;
  }
  api = GNUNET_new (struct GNUNET_NAMESTORE_PluginFunctions);
  api->cls = &plugin;
  api->store_records = &namestore_postgres_store_records;
  api->iterate_records = &namestore_postgres_iterate_records;
  api->zone_to_name = &namestore_postgres_zone_to_name;
  api->lookup_records = &namestore_postgres_lookup_records;
  LOG (GNUNET_ERROR_TYPE_INFO,
       _("Postgres database running\n"));
  return api;
}


/**
 * Exit point from the plugin.
 *
 * @param cls the plugin context (as returned by "init")
 * @return always NULL
 */
void *
libgnunet_plugin_namestore_postgres_done (void *cls)
{
  struct GNUNET_NAMESTORE_PluginFunctions *api = cls;
  struct Plugin *plugin = api->cls;

  database_shutdown (plugin);
  plugin->cfg = NULL;
  GNUNET_free (api);
  LOG (GNUNET_ERROR_TYPE_DEBUG,
       "postgres plugin is finished\n");
  return NULL;
}

/* end of plugin_namestore_postgres.c */