summaryrefslogtreecommitdiff
path: root/source4/dsdb/samdb/ldb_modules/schema_load.c
blob: b7b5f6bae74f4ffba736b7384d5b1cb1e9258877 (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
/* 
   Unix SMB/CIFS mplementation.

   The module that handles the Schema FSMO Role Owner
   checkings, it also loads the dsdb_schema.
   
   Copyright (C) Stefan Metzmacher <metze@samba.org> 2007
   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2009-2010

   This program 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 of the License, or
   (at your option) any later version.
   
   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
   
*/

#include "includes.h"
#include "ldb_module.h"
#include "dsdb/samdb/samdb.h"
#include "librpc/gen_ndr/ndr_misc.h"
#include "librpc/gen_ndr/ndr_drsuapi.h"
#include "librpc/gen_ndr/ndr_drsblobs.h"
#include "param/param.h"
#include "dsdb/samdb/ldb_modules/util.h"

struct schema_load_private_data {
	bool in_transaction;
};

static int dsdb_schema_from_db(struct ldb_module *module, struct ldb_dn *schema_dn, uint64_t current_usn,
			       struct dsdb_schema **schema);

static struct dsdb_schema *dsdb_schema_refresh(struct ldb_module *module, struct dsdb_schema *schema, bool is_global_schema)
{
	uint64_t current_usn;
	int ret;
	struct ldb_result *res;
	struct ldb_request *treq;
	struct ldb_seqnum_request *tseq;
	struct ldb_seqnum_result *tseqr;
	struct dsdb_control_current_partition *ctrl;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	struct dsdb_schema *new_schema;
	
	struct schema_load_private_data *private_data = talloc_get_type(ldb_module_get_private(module), struct schema_load_private_data);
	if (!private_data) {
		/* We can't refresh until the init function has run */
		return schema;
	}

	/* We don't allow a schema reload during a transaction - nobody else can modify our schema behind our backs */
	if (private_data->in_transaction) {
		return schema;
	}

	res = talloc_zero(schema, struct ldb_result);
	if (res == NULL) {
		return NULL;
	}
	tseq = talloc_zero(res, struct ldb_seqnum_request);
	if (tseq == NULL) {
		talloc_free(res);
		return NULL;
	}
	tseq->type = LDB_SEQ_HIGHEST_SEQ;
	
	ret = ldb_build_extended_req(&treq, ldb_module_get_ctx(module), res,
				     LDB_EXTENDED_SEQUENCE_NUMBER,
				     tseq,
				     NULL,
				     res,
				     ldb_extended_default_callback,
				     NULL);
	LDB_REQ_SET_LOCATION(treq);
	if (ret != LDB_SUCCESS) {
		talloc_free(res);
		return NULL;
	}
	
	ctrl = talloc(treq, struct dsdb_control_current_partition);
	if (!ctrl) {
		talloc_free(res);
		return NULL;
	}
	ctrl->version = DSDB_CONTROL_CURRENT_PARTITION_VERSION;
	ctrl->dn = schema->base_dn;
	
	ret = ldb_request_add_control(treq,
				      DSDB_CONTROL_CURRENT_PARTITION_OID,
				      false, ctrl);
	if (ret != LDB_SUCCESS) {
		talloc_free(res);
		return NULL;
	}
	
	ret = ldb_next_request(module, treq);
	if (ret != LDB_SUCCESS) {
		talloc_free(res);
		return NULL;
	}
	ret = ldb_wait(treq->handle, LDB_WAIT_ALL);
	if (ret != LDB_SUCCESS) {
		talloc_free(res);
		return NULL;
	}
	tseqr = talloc_get_type(res->extended->data,
				struct ldb_seqnum_result);
	if (tseqr->seq_num == schema->reload_seq_number) {
		talloc_free(res);
		return schema;
	}

	schema->reload_seq_number = tseqr->seq_num;
	talloc_free(res);
		
	ret = dsdb_module_load_partition_usn(module, schema->base_dn, &current_usn, NULL, NULL);
	if (ret != LDB_SUCCESS || current_usn == schema->loaded_usn) {
		return schema;
	}

	ret = dsdb_schema_from_db(module, schema->base_dn, current_usn, &new_schema);
	if (ret != LDB_SUCCESS) {
		return schema;
	}
	
	if (is_global_schema) {
		dsdb_make_schema_global(ldb, new_schema);
	}
	return new_schema;
}


/*
  Given an LDB module (pointing at the schema DB), and the DN, set the populated schema
*/

static int dsdb_schema_from_db(struct ldb_module *module, struct ldb_dn *schema_dn, uint64_t current_usn,
			       struct dsdb_schema **schema)
{
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	TALLOC_CTX *tmp_ctx;
	char *error_string;
	int ret;
	struct ldb_result *schema_res;
	struct ldb_result *a_res;
	struct ldb_result *c_res;
	static const char *schema_attrs[] = {
		"prefixMap",
		"schemaInfo",
		"fSMORoleOwner",
		NULL
	};
	unsigned flags;

	tmp_ctx = talloc_new(module);
	if (!tmp_ctx) {
		return ldb_oom(ldb);
	}

	/* we don't want to trace the schema load */
	flags = ldb_get_flags(ldb);
	ldb_set_flags(ldb, flags & ~LDB_FLG_ENABLE_TRACING);

	/*
	 * setup the prefix mappings and schema info
	 */
	ret = dsdb_module_search_dn(module, tmp_ctx, &schema_res,
				    schema_dn, schema_attrs,
				    DSDB_FLAG_NEXT_MODULE, NULL);
	if (ret == LDB_ERR_NO_SUCH_OBJECT) {
		ldb_reset_err_string(ldb);
		ldb_debug(ldb, LDB_DEBUG_WARNING,
			  "schema_load_init: no schema head present: (skip schema loading)\n");
		goto failed;
	} else if (ret != LDB_SUCCESS) {
		ldb_asprintf_errstring(ldb, 
				       "dsdb_schema: failed to search the schema head: %s",
				       ldb_errstring(ldb));
		goto failed;
	}

	/*
	 * load the attribute definitions
	 */
	ret = dsdb_module_search(module, tmp_ctx, &a_res,
				 schema_dn, LDB_SCOPE_ONELEVEL, NULL,
				 DSDB_FLAG_NEXT_MODULE,
				 NULL,
				 "(objectClass=attributeSchema)");
	if (ret != LDB_SUCCESS) {
		ldb_asprintf_errstring(ldb, 
				       "dsdb_schema: failed to search attributeSchema objects: %s",
				       ldb_errstring(ldb));
		goto failed;
	}

	/*
	 * load the objectClass definitions
	 */
	ret = dsdb_module_search(module, tmp_ctx, &c_res,
				 schema_dn, LDB_SCOPE_ONELEVEL, NULL,
				 DSDB_FLAG_NEXT_MODULE |
				 DSDB_SEARCH_SHOW_DN_IN_STORAGE_FORMAT,
				 NULL,
				 "(objectClass=classSchema)");
	if (ret != LDB_SUCCESS) {
		ldb_asprintf_errstring(ldb, 
				       "dsdb_schema: failed to search classSchema objects: %s",
				       ldb_errstring(ldb));
		goto failed;
	}

	ret = dsdb_schema_from_ldb_results(tmp_ctx, ldb,
					   schema_res, a_res, c_res, schema, &error_string);
	if (ret != LDB_SUCCESS) {
		ldb_asprintf_errstring(ldb, 
				       "dsdb_schema load failed: %s",
				       error_string);
		goto failed;
	}

	(*schema)->refresh_in_progress = true;

	/* If we have the readOnlySchema opaque, then don't check for
	 * runtime schema updates, as they are not permitted (we would
	 * have to update the backend server schema too */
	if (!ldb_get_opaque(ldb, "readOnlySchema")) {
		(*schema)->refresh_fn = dsdb_schema_refresh;
		(*schema)->loaded_from_module = module;
		(*schema)->loaded_usn = current_usn;
	}

	/* "dsdb_set_schema()" steals schema into the ldb_context */
	ret = dsdb_set_schema(ldb, (*schema));

	(*schema)->refresh_in_progress = false;

	if (ret != LDB_SUCCESS) {
		ldb_debug_set(ldb, LDB_DEBUG_FATAL,
			      "schema_load_init: dsdb_set_schema() failed: %d:%s: %s",
			      ret, ldb_strerror(ret), ldb_errstring(ldb));
		goto failed;
	}

	/* Ensure this module won't go away before the callback */
	if (talloc_reference(*schema, ldb) == NULL) {
		ldb_oom(ldb);
		ret = LDB_ERR_OPERATIONS_ERROR;
	}

failed:
	if (flags & LDB_FLG_ENABLE_TRACING) {
		flags = ldb_get_flags(ldb);
		ldb_set_flags(ldb, flags | LDB_FLG_ENABLE_TRACING);
	}
	talloc_free(tmp_ctx);
	return ret;
}	


static int schema_load_init(struct ldb_module *module)
{
	struct schema_load_private_data *private_data;
	struct dsdb_schema *schema;
	struct ldb_context *ldb = ldb_module_get_ctx(module);
	int ret;
	uint64_t current_usn;
	struct ldb_dn *schema_dn;

	private_data = talloc_zero(module, struct schema_load_private_data);
	if (private_data == NULL) {
		return ldb_oom(ldb);
	}

	ldb_module_set_private(module, private_data);

	ret = ldb_next_init(module);
	if (ret != LDB_SUCCESS) {
		return ret;
	}

	if (dsdb_get_schema(ldb, NULL)) {
		return LDB_SUCCESS;
	}

	schema_dn = ldb_get_schema_basedn(ldb);
	if (!schema_dn) {
		ldb_reset_err_string(ldb);
		ldb_debug(ldb, LDB_DEBUG_WARNING,
			  "schema_load_init: no schema dn present: (skip schema loading)\n");
		return LDB_SUCCESS;
	}

	ret = dsdb_module_load_partition_usn(module, schema_dn, &current_usn, NULL, NULL);
	if (ret != LDB_SUCCESS) {
		/* Ignore the error and just reload the DB more often */
		current_usn = 0;
	}

	return dsdb_schema_from_db(module, schema_dn, current_usn, &schema);
}

static int schema_load_start_transaction(struct ldb_module *module)
{
	struct schema_load_private_data *private_data =
		talloc_get_type(ldb_module_get_private(module), struct schema_load_private_data);

	private_data->in_transaction = true;

	return ldb_next_start_trans(module);
}

static int schema_load_end_transaction(struct ldb_module *module)
{
	struct schema_load_private_data *private_data =
		talloc_get_type(ldb_module_get_private(module), struct schema_load_private_data);

	private_data->in_transaction = false;

	return ldb_next_end_trans(module);
}

static int schema_load_del_transaction(struct ldb_module *module)
{
	struct schema_load_private_data *private_data =
		talloc_get_type(ldb_module_get_private(module), struct schema_load_private_data);

	private_data->in_transaction = false;

	return ldb_next_del_trans(module);
}

static int schema_load_extended(struct ldb_module *module, struct ldb_request *req)
{
	struct ldb_context *ldb;

	ldb = ldb_module_get_ctx(module);

	if (strcmp(req->op.extended.oid, DSDB_EXTENDED_SCHEMA_UPDATE_NOW_OID) != 0) {
		return ldb_next_request(module, req);
	}

	/* This is a no-op.  We reload as soon as we can */
	return ldb_module_done(req, NULL, NULL, LDB_SUCCESS);
}


static const struct ldb_module_ops ldb_schema_load_module_ops = {
	.name		= "schema_load",
	.init_context	= schema_load_init,
	.extended	= schema_load_extended,
	.start_transaction = schema_load_start_transaction,
	.end_transaction   = schema_load_end_transaction,
	.del_transaction   = schema_load_del_transaction,
};

int ldb_schema_load_module_init(const char *version)
{
	LDB_MODULE_CHECK_VERSION(version);
	return ldb_register_module(&ldb_schema_load_module_ops);
}