summaryrefslogtreecommitdiff
path: root/source3/lib/ldb/ldb_tdb/ldb_cache.c
blob: cc85479f88d2a875802a2683cffe7ab40a6ca36d (plain)
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
/* 
   ldb database library

   Copyright (C) Andrew Tridgell  2004

     ** NOTE! The following LGPL license applies to the ldb
     ** library. This does NOT imply that all of Samba is released
     ** under the LGPL
   
   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 3 of the License, or (at your option) any later version.

   This library 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
   Lesser General Public License for more details.

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

/*
 *  Name: ldb
 *
 *  Component: ldb tdb cache functions
 *
 *  Description: cache special records in a ldb/tdb
 *
 *  Author: Andrew Tridgell
 */

#include "includes.h"
#include "ldb/include/includes.h"

#include "ldb/ldb_tdb/ldb_tdb.h"

#define LTDB_FLAG_CASE_INSENSITIVE (1<<0)
#define LTDB_FLAG_INTEGER          (1<<1)
#define LTDB_FLAG_HIDDEN           (1<<2)
#define LTDB_FLAG_OBJECTCLASS      (1<<3)

int ltdb_attribute_flags(struct ldb_module *module, const char *attr_name);

/* valid attribute flags */
static const struct {
	const char *name;
	int value;
} ltdb_valid_attr_flags[] = {
	{ "CASE_INSENSITIVE", LTDB_FLAG_CASE_INSENSITIVE },
	{ "INTEGER", LTDB_FLAG_INTEGER },
	{ "HIDDEN", LTDB_FLAG_HIDDEN },
	{ "NONE", 0 },
	{ NULL, 0 }
};


/*
  de-register any special handlers for @ATTRIBUTES
*/
static void ltdb_attributes_unload(struct ldb_module *module)
{
	struct ltdb_private *ltdb =
		(struct ltdb_private *)module->private_data;
	struct ldb_message *msg;
	int i;

	if (ltdb->cache->attributes == NULL) {
		/* no previously loaded attributes */
		return;
	}

	msg = ltdb->cache->attributes;
	for (i=0;i<msg->num_elements;i++) {
		ldb_remove_attrib_handler(module->ldb, msg->elements[i].name);
	}

	talloc_free(ltdb->cache->attributes);
	ltdb->cache->attributes = NULL;
}

/*
  add up the attrib flags for a @ATTRIBUTES element
*/
static int ltdb_attributes_flags(struct ldb_message_element *el, unsigned *v)
{
	int i;
	unsigned value = 0;
	for (i=0;i<el->num_values;i++) {
		int j;
		for (j=0;ltdb_valid_attr_flags[j].name;j++) {
			if (strcmp(ltdb_valid_attr_flags[j].name, 
				   (char *)el->values[i].data) == 0) {
				value |= ltdb_valid_attr_flags[j].value;
				break;
			}
		}
		if (ltdb_valid_attr_flags[j].name == NULL) {
			return -1;
		}
	}
	*v = value;
	return 0;
}

/*
  register any special handlers from @ATTRIBUTES
*/
static int ltdb_attributes_load(struct ldb_module *module)
{
	struct ltdb_private *ltdb =
		(struct ltdb_private *)module->private_data;
	struct ldb_message *msg = ltdb->cache->attributes;
	struct ldb_dn *dn;
	int i;

	dn = ldb_dn_explode(module->ldb, LTDB_ATTRIBUTES);
	if (dn == NULL) goto failed;

	if (ltdb_search_dn1(module, dn, msg) == -1) {
		talloc_free(dn);
		goto failed;
	}
	talloc_free(dn);
	/* mapping these flags onto ldap 'syntaxes' isn't strictly correct,
	   but its close enough for now */
	for (i=0;i<msg->num_elements;i++) {
		unsigned flags;
		const char *syntax;
		const struct ldb_attrib_handler *h;
		struct ldb_attrib_handler h2;

		if (ltdb_attributes_flags(&msg->elements[i], &flags) != 0) {
			ldb_debug(module->ldb, LDB_DEBUG_ERROR, "Invalid @ATTRIBUTES element for '%s'\n", msg->elements[i].name);
			goto failed;
		}
		switch (flags & ~LTDB_FLAG_HIDDEN) {
		case 0:
			syntax = LDB_SYNTAX_OCTET_STRING;
			break;
		case LTDB_FLAG_CASE_INSENSITIVE:
			syntax = LDB_SYNTAX_DIRECTORY_STRING;
			break;
		case LTDB_FLAG_INTEGER:
			syntax = LDB_SYNTAX_INTEGER;
			break;
		default:
			ldb_debug(module->ldb, LDB_DEBUG_ERROR, 
				  "Invalid flag combination 0x%x for '%s' in @ATTRIBUTES\n",
				  flags, msg->elements[i].name);
			goto failed;
		}

		h = ldb_attrib_handler_syntax(module->ldb, syntax);
		if (h == NULL) {
			ldb_debug(module->ldb, LDB_DEBUG_ERROR, 
				  "Invalid attribute syntax '%s' for '%s' in @ATTRIBUTES\n",
				  syntax, msg->elements[i].name);
			goto failed;
		}
		h2 = *h;
		h2.attr = msg->elements[i].name;
		h2.flags |= LDB_ATTR_FLAG_ALLOCATED;
		if (ldb_set_attrib_handlers(module->ldb, &h2, 1) != 0) {
			goto failed;
		}
	}

	return 0;
failed:
	return -1;
}


/*
  register any subclasses from @SUBCLASSES
*/
static int ltdb_subclasses_load(struct ldb_module *module)
{
	struct ltdb_private *ltdb =
		(struct ltdb_private *)module->private_data;
	struct ldb_message *msg = ltdb->cache->subclasses;
	struct ldb_dn *dn;
	int i, j;

	dn = ldb_dn_explode(module->ldb, LTDB_SUBCLASSES);
	if (dn == NULL) goto failed;

	if (ltdb_search_dn1(module, dn, msg) == -1) {
		talloc_free(dn);
		goto failed;
	}
	talloc_free(dn);

	for (i=0;i<msg->num_elements;i++) {
		struct ldb_message_element *el = &msg->elements[i];
		for (j=0;j<el->num_values;j++) {
			if (ldb_subclass_add(module->ldb, el->name, 
					     (char *)el->values[j].data) != 0) {
				goto failed;
			}
		}
	}

	return 0;
failed:
	return -1;
}


/*
  de-register any @SUBCLASSES
*/
static void ltdb_subclasses_unload(struct ldb_module *module)
{
	struct ltdb_private *ltdb =
		(struct ltdb_private *)module->private_data;
	struct ldb_message *msg;
	int i;

	if (ltdb->cache->subclasses == NULL) {
		/* no previously loaded subclasses */
		return;
	}

	msg = ltdb->cache->subclasses;
	for (i=0;i<msg->num_elements;i++) {
		ldb_subclass_remove(module->ldb, msg->elements[i].name);
	}

	talloc_free(ltdb->cache->subclasses);
	ltdb->cache->subclasses = NULL;
}


/*
  initialise the baseinfo record
*/
static int ltdb_baseinfo_init(struct ldb_module *module)
{
	struct ltdb_private *ltdb =
		(struct ltdb_private *)module->private_data;
	struct ldb_message *msg;
	struct ldb_message_element el;
	struct ldb_val val;
	int ret;
	/* the initial sequence number must be different from the one
	   set in ltdb_cache_free(). Thanks to Jon for pointing this
	   out. */
	const char *initial_sequence_number = "1";

	ltdb->sequence_number = atof(initial_sequence_number);

	msg = talloc(ltdb, struct ldb_message);
	if (msg == NULL) {
		goto failed;
	}

	msg->num_elements = 1;
	msg->elements = &el;
	msg->dn = ldb_dn_explode(msg, LTDB_BASEINFO);
	if (!msg->dn) {
		goto failed;
	}
	el.name = talloc_strdup(msg, LTDB_SEQUENCE_NUMBER);
	if (!el.name) {
		goto failed;
	}
	el.values = &val;
	el.num_values = 1;
	el.flags = 0;
	val.data = (uint8_t *)talloc_strdup(msg, initial_sequence_number);
	if (!val.data) {
		goto failed;
	}
	val.length = 1;
	
	ret = ltdb_store(module, msg, TDB_INSERT);

	talloc_free(msg);

	return ret;

failed:
	talloc_free(msg);
	errno = ENOMEM;
	return -1;
}

/*
  free any cache records
 */
static void ltdb_cache_free(struct ldb_module *module)
{
	struct ltdb_private *ltdb =
		(struct ltdb_private *)module->private_data;

	ltdb->sequence_number = 0;
	talloc_free(ltdb->cache);
	ltdb->cache = NULL;
}

/*
  force a cache reload
*/
int ltdb_cache_reload(struct ldb_module *module)
{
	ltdb_attributes_unload(module);
	ltdb_subclasses_unload(module);
	ltdb_cache_free(module);
	return ltdb_cache_load(module);
}

/*
  load the cache records
*/
int ltdb_cache_load(struct ldb_module *module)
{
	struct ltdb_private *ltdb =
		(struct ltdb_private *)module->private_data;
	struct ldb_dn *baseinfo_dn = NULL;
	struct ldb_dn *indexlist_dn = NULL;
	uint64_t seq;
	struct ldb_message *baseinfo = NULL;

	/* a very fast check to avoid extra database reads */
	if (ltdb->cache != NULL && 
	    tdb_get_seqnum(ltdb->tdb) == ltdb->tdb_seqnum) {
		return 0;
	}

	if (ltdb->cache == NULL) {
		ltdb->cache = talloc_zero(ltdb, struct ltdb_cache);
		if (ltdb->cache == NULL) goto failed;
		ltdb->cache->indexlist = talloc_zero(ltdb->cache, struct ldb_message);
		ltdb->cache->subclasses = talloc_zero(ltdb->cache, struct ldb_message);
		ltdb->cache->attributes = talloc_zero(ltdb->cache, struct ldb_message);
		if (ltdb->cache->indexlist == NULL ||
		    ltdb->cache->subclasses == NULL ||
		    ltdb->cache->attributes == NULL) {
			goto failed;
		}
	}

	baseinfo = talloc(ltdb->cache, struct ldb_message);
	if (baseinfo == NULL) goto failed;

	baseinfo_dn = ldb_dn_explode(module->ldb, LTDB_BASEINFO);
	if (baseinfo_dn == NULL) goto failed;

	if (ltdb_search_dn1(module, baseinfo_dn, baseinfo) == -1) {
		goto failed;
	}
	
	/* possibly initialise the baseinfo */
	if (!baseinfo->dn) {
		if (ltdb_baseinfo_init(module) != 0) {
			goto failed;
		}
		if (ltdb_search_dn1(module, baseinfo_dn, baseinfo) != 1) {
			goto failed;
		}
	}

	ltdb->tdb_seqnum = tdb_get_seqnum(ltdb->tdb);

	/* if the current internal sequence number is the same as the one
	   in the database then assume the rest of the cache is OK */
	seq = ldb_msg_find_attr_as_uint64(baseinfo, LTDB_SEQUENCE_NUMBER, 0);
	if (seq == ltdb->sequence_number) {
		goto done;
	}
	ltdb->sequence_number = seq;

	talloc_free(ltdb->cache->last_attribute.name);
	memset(&ltdb->cache->last_attribute, 0, sizeof(ltdb->cache->last_attribute));

	ltdb_attributes_unload(module);
	ltdb_subclasses_unload(module);

	talloc_free(ltdb->cache->indexlist);
	talloc_free(ltdb->cache->subclasses);

	ltdb->cache->indexlist = talloc_zero(ltdb->cache, struct ldb_message);
	ltdb->cache->subclasses = talloc_zero(ltdb->cache, struct ldb_message);
	ltdb->cache->attributes = talloc_zero(ltdb->cache, struct ldb_message);
	if (ltdb->cache->indexlist == NULL ||
	    ltdb->cache->subclasses == NULL ||
	    ltdb->cache->attributes == NULL) {
		goto failed;
	}
	    
	indexlist_dn = ldb_dn_explode(module->ldb, LTDB_INDEXLIST);
	if (indexlist_dn == NULL) goto failed;

	if (ltdb_search_dn1(module, indexlist_dn, ltdb->cache->indexlist) == -1) {
		goto failed;
	}

	if (ltdb_attributes_load(module) == -1) {
		goto failed;
	}
	if (ltdb_subclasses_load(module) == -1) {
		goto failed;
	}

done:
	talloc_free(baseinfo);
	talloc_free(baseinfo_dn);
	talloc_free(indexlist_dn);
	return 0;

failed:
	talloc_free(baseinfo);
	talloc_free(baseinfo_dn);
	talloc_free(indexlist_dn);
	return -1;
}


/*
  increase the sequence number to indicate a database change
*/
int ltdb_increase_sequence_number(struct ldb_module *module)
{
	struct ltdb_private *ltdb =
		(struct ltdb_private *)module->private_data;
	struct ldb_message *msg;
	struct ldb_message_element el[2];
	struct ldb_val val;
	struct ldb_val val_time;
	time_t t = time(NULL);
	char *s = NULL;
	int ret;

	msg = talloc(ltdb, struct ldb_message);
	if (msg == NULL) {
		errno = ENOMEM;
		return -1;
	}

	s = talloc_asprintf(msg, "%llu", ltdb->sequence_number+1);
	if (!s) {
		errno = ENOMEM;
		return -1;
	}

	msg->num_elements = ARRAY_SIZE(el);
	msg->elements = el;
	msg->dn = ldb_dn_explode(msg, LTDB_BASEINFO);
	if (msg->dn == NULL) {
		talloc_free(msg);
		errno = ENOMEM;
		return -1;
	}
	el[0].name = talloc_strdup(msg, LTDB_SEQUENCE_NUMBER);
	if (el[0].name == NULL) {
		talloc_free(msg);
		errno = ENOMEM;
		return -1;
	}
	el[0].values = &val;
	el[0].num_values = 1;
	el[0].flags = LDB_FLAG_MOD_REPLACE;
	val.data = (uint8_t *)s;
	val.length = strlen(s);

	el[1].name = talloc_strdup(msg, LTDB_MOD_TIMESTAMP);
	if (el[1].name == NULL) {
		talloc_free(msg);
		errno = ENOMEM;
		return -1;
	}
	el[1].values = &val_time;
	el[1].num_values = 1;
	el[1].flags = LDB_FLAG_MOD_REPLACE;

	s = ldb_timestring(msg, t);
	if (s == NULL) {
		return -1;
	}

	val_time.data = (uint8_t *)s;
	val_time.length = strlen(s);

	ret = ltdb_modify_internal(module, msg);

	talloc_free(msg);

	if (ret == 0) {
		ltdb->sequence_number += 1;
	}

	return ret;
}


/*
  return the attribute flags from the @ATTRIBUTES record 
  for the given attribute
*/
int ltdb_attribute_flags(struct ldb_module *module, const char *attr_name)
{
	struct ltdb_private *ltdb =
		(struct ltdb_private *)module->private_data;
	const struct ldb_message_element *attr_el;
	int i, j, ret=0;

	if (ltdb->cache->last_attribute.name &&
	    ldb_attr_cmp(ltdb->cache->last_attribute.name, attr_name) == 0) {
		return ltdb->cache->last_attribute.flags;
	}

	/* objectclass is a special default case */
	if (ldb_attr_cmp(attr_name, LTDB_OBJECTCLASS) == 0) {
		ret = LTDB_FLAG_OBJECTCLASS | LTDB_FLAG_CASE_INSENSITIVE;
	}

	attr_el = ldb_msg_find_element(ltdb->cache->attributes, attr_name);

	if (!attr_el) {
		/* check if theres a wildcard attribute */
		attr_el = ldb_msg_find_element(ltdb->cache->attributes, "*");

		if (!attr_el) {
			return ret;
		}
	}

	for (i = 0; i < attr_el->num_values; i++) {
		for (j=0; ltdb_valid_attr_flags[j].name; j++) {
			if (strcmp(ltdb_valid_attr_flags[j].name, 
				   (char *)attr_el->values[i].data) == 0) {
				ret |= ltdb_valid_attr_flags[j].value;
			}
		}
	}

	talloc_free(ltdb->cache->last_attribute.name);

	ltdb->cache->last_attribute.name = talloc_strdup(ltdb->cache, attr_name);
	ltdb->cache->last_attribute.flags = ret;

	return ret;
}

int ltdb_check_at_attributes_values(const struct ldb_val *value)
{
	int i;

	for (i = 0; ltdb_valid_attr_flags[i].name != NULL; i++) {
		if ((strcmp(ltdb_valid_attr_flags[i].name, (char *)value->data) == 0)) {
			return 0;
		}
	}

	return -1;
}