summaryrefslogtreecommitdiff
path: root/source4/dns_server/dlz_bind9.c
blob: 51971f676cb115b314df7f2f9dd0f658579c6e46 (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
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
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
/*
   Unix SMB/CIFS implementation.

   bind9 dlz driver for Samba

   Copyright (C) 2010 Andrew Tridgell

   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 "talloc.h"
#include "param/param.h"
#include "lib/events/events.h"
#include "dsdb/samdb/samdb.h"
#include "dsdb/common/util.h"
#include "auth/session.h"
#include "auth/gensec/gensec.h"
#include "gen_ndr/ndr_dnsp.h"
#include "lib/cmdline/popt_common.h"
#include "lib/cmdline/popt_credentials.h"
#include "ldb_module.h"
#include "dlz_minimal.h"

struct dlz_bind9_data {
	struct ldb_context *samdb;
	struct tevent_context *ev_ctx;
	struct loadparm_context *lp;
	bool transaction_started;

	/* helper functions from the dlz_dlopen driver */
	void (*log)(int level, const char *fmt, ...);
	isc_result_t (*putrr)(dns_sdlzlookup_t *handle, const char *type,
			      dns_ttl_t ttl, const char *data);
	isc_result_t (*putnamedrr)(dns_sdlzlookup_t *handle, const char *name,
				   const char *type, dns_ttl_t ttl, const char *data);
	isc_result_t (*writeable_zone)(dns_view_t *view, const char *zone_name);
};


static const char *zone_prefixes[] = {
	"CN=MicrosoftDNS,DC=DomainDnsZones",
	"CN=MicrosoftDNS,DC=ForestDnsZones",
	NULL
};

/*
  return the version of the API
 */
_PUBLIC_ int dlz_version(unsigned int *flags)
{
	return DLZ_DLOPEN_VERSION;
}

/*
   remember a helper function from the bind9 dlz_dlopen driver
 */
static void b9_add_helper(struct dlz_bind9_data *state, const char *helper_name, void *ptr)
{
	if (strcmp(helper_name, "log") == 0) {
		state->log = ptr;
	}
	if (strcmp(helper_name, "putrr") == 0) {
		state->putrr = ptr;
	}
	if (strcmp(helper_name, "putnamedrr") == 0) {
		state->putnamedrr = ptr;
	}
	if (strcmp(helper_name, "writeable_zone") == 0) {
		state->writeable_zone = ptr;
	}
}

/*
  format a record for bind9
 */
static bool b9_format(struct dlz_bind9_data *state,
		      TALLOC_CTX *mem_ctx,
		      struct dnsp_DnssrvRpcRecord *rec,
		      const char **type, const char **data)
{
	switch (rec->wType) {
	case DNS_TYPE_A:
		*type = "a";
		*data = rec->data.ipv4;
		break;

	case DNS_TYPE_AAAA:
		*type = "aaaa";
		*data = rec->data.ipv6;
		break;

	case DNS_TYPE_CNAME:
		*type = "cname";
		*data = rec->data.cname;
		break;

	case DNS_TYPE_TXT:
		*type = "txt";
		*data = rec->data.txt;
		break;

	case DNS_TYPE_PTR:
		*type = "ptr";
		*data = rec->data.ptr;
		break;

	case DNS_TYPE_SRV:
		*type = "srv";
		*data = talloc_asprintf(mem_ctx, "%u %u %u %s",
					rec->data.srv.wPriority,
					rec->data.srv.wWeight,
					rec->data.srv.wPort,
					rec->data.srv.nameTarget);
		break;

	case DNS_TYPE_MX:
		*type = "mx";
		*data = talloc_asprintf(mem_ctx, "%u %s",
					rec->data.srv.wPriority,
					rec->data.srv.nameTarget);
		break;

	case DNS_TYPE_HINFO:
		*type = "hinfo";
		*data = talloc_asprintf(mem_ctx, "%s %s",
					rec->data.hinfo.cpu,
					rec->data.hinfo.os);
		break;

	case DNS_TYPE_NS:
		*type = "ns";
		*data = rec->data.ns;
		break;

	case DNS_TYPE_SOA:
		*type = "soa";
		*data = talloc_asprintf(mem_ctx, "%s %s %u %u %u %u %u",
					rec->data.soa.mname,
					rec->data.soa.rname,
					rec->data.soa.serial,
					rec->data.soa.refresh,
					rec->data.soa.retry,
					rec->data.soa.expire,
					rec->data.soa.minimum);
		break;

	default:
		state->log(ISC_LOG_ERROR, "samba b9_putrr: unhandled record type %u",
			   rec->wType);
		return false;
	}

	return true;
}

/*
  parse a record from bind9
 */
static bool b9_parse(struct dlz_bind9_data *state,
		     TALLOC_CTX *mem_ctx,
		     struct dnsp_DnssrvRpcRecord *rec,
		     const char **type, const char **data)
{
	return false;
}

/*
  send a resource recond to bind9
 */
static isc_result_t b9_putrr(struct dlz_bind9_data *state,
			     void *handle, struct dnsp_DnssrvRpcRecord *rec,
			     const char **types)
{
	isc_result_t result;
	const char *type, *data;
	TALLOC_CTX *tmp_ctx = talloc_new(state);

	if (!b9_format(state, tmp_ctx, rec, &type, &data)) {
		return ISC_R_FAILURE;
	}

	if (data == NULL) {
		talloc_free(tmp_ctx);
		return ISC_R_NOMEMORY;
	}

	if (types) {
		int i;
		for (i=0; types[i]; i++) {
			if (strcmp(types[i], type) == 0) break;
		}
		if (types[i] == NULL) {
			/* skip it */
			return ISC_R_SUCCESS;
		}
	}

	result = state->putrr(handle, type, rec->dwTtlSeconds, data);
	if (result != ISC_R_SUCCESS) {
		state->log(ISC_LOG_ERROR, "Failed to put rr");
	}
	talloc_free(tmp_ctx);
	return result;
}


/*
  send a named resource recond to bind9
 */
static isc_result_t b9_putnamedrr(struct dlz_bind9_data *state,
				  void *handle, const char *name,
				  struct dnsp_DnssrvRpcRecord *rec)
{
	isc_result_t result;
	const char *type, *data;
	TALLOC_CTX *tmp_ctx = talloc_new(state);

	if (!b9_format(state, tmp_ctx, rec, &type, &data)) {
		return ISC_R_FAILURE;
	}

	if (data == NULL) {
		talloc_free(tmp_ctx);
		return ISC_R_NOMEMORY;
	}

	result = state->putnamedrr(handle, name, type, rec->dwTtlSeconds, data);
	if (result != ISC_R_SUCCESS) {
		state->log(ISC_LOG_ERROR, "Failed to put named rr '%s'", name);
	}
	talloc_free(tmp_ctx);
	return result;
}

struct b9_options {
	const char *url;
};

/*
   parse options
 */
static isc_result_t parse_options(struct dlz_bind9_data *state,
				  unsigned int argc, char *argv[],
				  struct b9_options *options)
{
	int opt;
	poptContext pc;
	struct poptOption long_options[] = {
		{ "url",       'H', POPT_ARG_STRING, &options->url, 0, "database URL", "URL" },
		{ NULL }
	};
	struct poptOption **popt_options;
	int ret;

	popt_options = ldb_module_popt_options(state->samdb);
	(*popt_options) = long_options;

	ret = ldb_modules_hook(state->samdb, LDB_MODULE_HOOK_CMDLINE_OPTIONS);
	if (ret != LDB_SUCCESS) {
		state->log(ISC_LOG_ERROR, "dlz samba: failed cmdline hook");
		return ISC_R_FAILURE;
	}

	pc = poptGetContext("dlz_bind9", argc, (const char **)argv, *popt_options,
			    POPT_CONTEXT_KEEP_FIRST);

	while ((opt = poptGetNextOpt(pc)) != -1) {
		switch (opt) {
		default:
			state->log(ISC_LOG_ERROR, "dlz samba: Invalid option %s: %s",
				   poptBadOption(pc, 0), poptStrerror(opt));
			return ISC_R_FAILURE;
		}
	}

	ret = ldb_modules_hook(state->samdb, LDB_MODULE_HOOK_CMDLINE_PRECONNECT);
	if (ret != LDB_SUCCESS) {
		state->log(ISC_LOG_ERROR, "dlz samba: failed cmdline preconnect");
		return ISC_R_FAILURE;
	}

	return ISC_R_SUCCESS;
}


/*
  called to initialise the driver
 */
_PUBLIC_ isc_result_t dlz_create(const char *dlzname,
				 unsigned int argc, char *argv[],
				 void **dbdata, ...)
{
	struct dlz_bind9_data *state;
	const char *helper_name;
	va_list ap;
	isc_result_t result;
	TALLOC_CTX *tmp_ctx;
	int ret;
	struct ldb_dn *dn;
	struct b9_options options;

	ZERO_STRUCT(options);

	state = talloc_zero(NULL, struct dlz_bind9_data);
	if (state == NULL) {
		return ISC_R_NOMEMORY;
	}

	tmp_ctx = talloc_new(state);

	/* fill in the helper functions */
	va_start(ap, dbdata);
	while ((helper_name = va_arg(ap, const char *)) != NULL) {
		b9_add_helper(state, helper_name, va_arg(ap, void*));
	}
	va_end(ap);

	state->ev_ctx = s4_event_context_init(state);
	if (state->ev_ctx == NULL) {
		result = ISC_R_NOMEMORY;
		goto failed;
	}

	state->samdb = ldb_init(state, state->ev_ctx);
	if (state->samdb == NULL) {
		state->log(ISC_LOG_ERROR, "samba dlz_bind9: Failed to create ldb");
		result = ISC_R_FAILURE;
		goto failed;
	}

	result = parse_options(state, argc, argv, &options);
	if (result != ISC_R_SUCCESS) {
		goto failed;
	}

	state->lp = loadparm_init_global(true);
	if (state->lp == NULL) {
		result = ISC_R_NOMEMORY;
		goto failed;
	}

	if (options.url == NULL) {
		options.url = talloc_asprintf(tmp_ctx, "ldapi://%s",
					      private_path(tmp_ctx, state->lp, "ldap_priv/ldapi"));
		if (options.url == NULL) {
			result = ISC_R_NOMEMORY;
			goto failed;
		}
	}

	ret = ldb_connect(state->samdb, options.url, 0, NULL);
	if (ret == -1) {
		state->log(ISC_LOG_ERROR, "samba dlz_bind9: Failed to connect to %s - %s",
			   options.url, ldb_errstring(state->samdb));
		result = ISC_R_FAILURE;
		goto failed;
	}

	ret = ldb_modules_hook(state->samdb, LDB_MODULE_HOOK_CMDLINE_POSTCONNECT);
	if (ret != LDB_SUCCESS) {
		state->log(ISC_LOG_ERROR, "samba dlz_bind9: Failed postconnect for %s - %s",
			   options.url, ldb_errstring(state->samdb));
		result = ISC_R_FAILURE;
		goto failed;
	}

	dn = ldb_get_default_basedn(state->samdb);
	if (dn == NULL) {
		state->log(ISC_LOG_ERROR, "samba dlz_bind9: Unable to get basedn for %s - %s",
			   options.url, ldb_errstring(state->samdb));
		result = ISC_R_FAILURE;
		goto failed;
	}

	state->log(ISC_LOG_INFO, "samba dlz_bind9: started for DN %s",
		   ldb_dn_get_linearized(dn));

	*dbdata = state;

	talloc_free(tmp_ctx);
	return ISC_R_SUCCESS;

failed:
	talloc_free(state);
	return result;
}

/*
  shutdown the backend
 */
_PUBLIC_ void dlz_destroy(void *dbdata)
{
	struct dlz_bind9_data *state = talloc_get_type_abort(dbdata, struct dlz_bind9_data);
	state->log(ISC_LOG_INFO, "samba dlz_bind9: shutting down");
	talloc_free(state);
}


/*
  see if we handle a given zone
 */
_PUBLIC_ isc_result_t dlz_findzonedb(void *dbdata, const char *name)
{
	struct dlz_bind9_data *state = talloc_get_type_abort(dbdata, struct dlz_bind9_data);
	int ret;
	TALLOC_CTX *tmp_ctx = talloc_new(state);
	const char *attrs[] = { NULL };
	int i;

	for (i=0; zone_prefixes[i]; i++) {
		struct ldb_dn *dn;
		struct ldb_result *res;

		dn = ldb_dn_copy(tmp_ctx, ldb_get_default_basedn(state->samdb));
		if (dn == NULL) {
			talloc_free(tmp_ctx);
			return ISC_R_NOMEMORY;
		}

		if (!ldb_dn_add_child_fmt(dn, "DC=%s,%s", name, zone_prefixes[i])) {
			talloc_free(tmp_ctx);
			return ISC_R_NOMEMORY;
		}

		ret = ldb_search(state->samdb, tmp_ctx, &res, dn, LDB_SCOPE_BASE, attrs, "objectClass=dnsZone");
		if (ret == LDB_SUCCESS) {
			talloc_free(tmp_ctx);
			return ISC_R_SUCCESS;
		}
		talloc_free(dn);
	}

	talloc_free(tmp_ctx);
	return ISC_R_NOTFOUND;
}


/*
  lookup one record
 */
static isc_result_t dlz_lookup_types(struct dlz_bind9_data *state,
				     const char *zone, const char *name,
				     dns_sdlzlookup_t *lookup,
				     const char **types)
{
	TALLOC_CTX *tmp_ctx = talloc_new(state);
	const char *attrs[] = { "dnsRecord", NULL };
	int ret, i;
	struct ldb_result *res;
	struct ldb_message_element *el;
	struct ldb_dn *dn;

	for (i=0; zone_prefixes[i]; i++) {
		dn = ldb_dn_copy(tmp_ctx, ldb_get_default_basedn(state->samdb));
		if (dn == NULL) {
			talloc_free(tmp_ctx);
			return ISC_R_NOMEMORY;
		}

		if (!ldb_dn_add_child_fmt(dn, "DC=%s,DC=%s,%s", name, zone, zone_prefixes[i])) {
			talloc_free(tmp_ctx);
			return ISC_R_NOMEMORY;
		}

		ret = ldb_search(state->samdb, tmp_ctx, &res, dn, LDB_SCOPE_BASE,
				 attrs, "objectClass=dnsNode");
		if (ret == LDB_SUCCESS) {
			break;
		}
	}
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ISC_R_NOTFOUND;
	}

	el = ldb_msg_find_element(res->msgs[0], "dnsRecord");
	if (el == NULL || el->num_values == 0) {
		talloc_free(tmp_ctx);
		return ISC_R_NOTFOUND;
	}

	for (i=0; i<el->num_values; i++) {
		struct dnsp_DnssrvRpcRecord rec;
		enum ndr_err_code ndr_err;
		isc_result_t result;

		ndr_err = ndr_pull_struct_blob(&el->values[i], tmp_ctx, &rec,
					       (ndr_pull_flags_fn_t)ndr_pull_dnsp_DnssrvRpcRecord);
		if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
			state->log(ISC_LOG_ERROR, "samba dlz_bind9: failed to parse dnsRecord for %s",
				   ldb_dn_get_linearized(dn));
			talloc_free(tmp_ctx);
			return ISC_R_FAILURE;
		}

		result = b9_putrr(state, lookup, &rec, types);
		if (result != ISC_R_SUCCESS) {
			talloc_free(tmp_ctx);
			return result;
		}
	}

	talloc_free(tmp_ctx);
	return ISC_R_SUCCESS;
}

/*
  lookup one record
 */
_PUBLIC_ isc_result_t dlz_lookup(const char *zone, const char *name,
				 void *dbdata, dns_sdlzlookup_t *lookup)
{
	struct dlz_bind9_data *state = talloc_get_type_abort(dbdata, struct dlz_bind9_data);
	return dlz_lookup_types(state, zone, name, lookup, NULL);
}


/*
  see if a zone transfer is allowed
 */
_PUBLIC_ isc_result_t dlz_allowzonexfr(void *dbdata, const char *name, const char *client)
{
	/* just say yes for all our zones for now */
	return dlz_findzonedb(dbdata, name);
}

/*
  perform a zone transfer
 */
_PUBLIC_ isc_result_t dlz_allnodes(const char *zone, void *dbdata,
				   dns_sdlzallnodes_t *allnodes)
{
	struct dlz_bind9_data *state = talloc_get_type_abort(dbdata, struct dlz_bind9_data);
	const char *attrs[] = { "dnsRecord", NULL };
	int ret, i, j;
	struct ldb_dn *dn;
	struct ldb_result *res;
	TALLOC_CTX *tmp_ctx = talloc_new(state);

	for (i=0; zone_prefixes[i]; i++) {
		dn = ldb_dn_copy(tmp_ctx, ldb_get_default_basedn(state->samdb));
		if (dn == NULL) {
			talloc_free(tmp_ctx);
			return ISC_R_NOMEMORY;
		}

		if (!ldb_dn_add_child_fmt(dn, "DC=%s,%s", zone, zone_prefixes[i])) {
			talloc_free(tmp_ctx);
			return ISC_R_NOMEMORY;
		}

		ret = ldb_search(state->samdb, tmp_ctx, &res, dn, LDB_SCOPE_SUBTREE,
				 attrs, "objectClass=dnsNode");
		if (ret == LDB_SUCCESS) {
			break;
		}
	}
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return ISC_R_NOTFOUND;
	}

	for (i=0; i<res->count; i++) {
		struct ldb_message_element *el;
		TALLOC_CTX *el_ctx = talloc_new(tmp_ctx);
		const char *rdn, *name;
		const struct ldb_val *v;

		el = ldb_msg_find_element(res->msgs[i], "dnsRecord");
		if (el == NULL || el->num_values == 0) {
			state->log(ISC_LOG_INFO, "failed to find dnsRecord for %s",
				   ldb_dn_get_linearized(dn));
			talloc_free(el_ctx);
			continue;
		}

		v = ldb_dn_get_rdn_val(res->msgs[i]->dn);
		if (v == NULL) {
			state->log(ISC_LOG_INFO, "failed to find RDN for %s",
				   ldb_dn_get_linearized(dn));
			talloc_free(el_ctx);
			continue;
		}

		rdn = talloc_strndup(el_ctx, (char *)v->data, v->length);
		if (rdn == NULL) {
			talloc_free(tmp_ctx);
			return ISC_R_NOMEMORY;
		}

		if (strcmp(rdn, "@") == 0) {
			name = zone;
		} else {
			name = talloc_asprintf(el_ctx, "%s.%s", rdn, zone);
		}
		if (name == NULL) {
			talloc_free(tmp_ctx);
			return ISC_R_NOMEMORY;
		}

		for (j=0; j<el->num_values; j++) {
			struct dnsp_DnssrvRpcRecord rec;
			enum ndr_err_code ndr_err;
			isc_result_t result;

			ndr_err = ndr_pull_struct_blob(&el->values[j], el_ctx, &rec,
						       (ndr_pull_flags_fn_t)ndr_pull_dnsp_DnssrvRpcRecord);
			if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
				state->log(ISC_LOG_ERROR, "samba dlz_bind9: failed to parse dnsRecord for %s",
					   ldb_dn_get_linearized(dn));
				talloc_free(el_ctx);
				continue;
			}

			result = b9_putnamedrr(state, allnodes, name, &rec);
			if (result != ISC_R_SUCCESS) {
				talloc_free(el_ctx);
				continue;
			}
		}
	}

	talloc_free(tmp_ctx);

	return ISC_R_SUCCESS;
}


/*
  start a transaction
 */
_PUBLIC_ isc_result_t dlz_newversion(const char *zone, void *dbdata, void **versionp)
{
	struct dlz_bind9_data *state = talloc_get_type_abort(dbdata, struct dlz_bind9_data);

	state->log(ISC_LOG_INFO, "samba dlz_bind9: starting transaction on zone %s", zone);

	if (state->transaction_started) {
		state->log(ISC_LOG_INFO, "samba dlz_bind9: transaction already started for zone %s", zone);
		return ISC_R_FAILURE;
	}

	state->transaction_started = true;

	*versionp = (void *) &state->transaction_started;

	return ISC_R_SUCCESS;
}

/*
  end a transaction
 */
_PUBLIC_ void dlz_closeversion(const char *zone, isc_boolean_t commit,
			       void *dbdata, void **versionp)
{
	struct dlz_bind9_data *state = talloc_get_type_abort(dbdata, struct dlz_bind9_data);

	if (!state->transaction_started) {
		state->log(ISC_LOG_INFO, "samba dlz_bind9: transaction not started for zone %s", zone);
		*versionp = NULL;
		return;
	}

	state->transaction_started = false;

	*versionp = NULL;

	if (commit) {
		state->log(ISC_LOG_INFO, "samba dlz_bind9: committing transaction on zone %s", zone);
	} else {
		state->log(ISC_LOG_INFO, "samba dlz_bind9: cancelling transaction on zone %s", zone);
	}
}


/*
  see if there is a SOA record for a zone
 */
static bool b9_has_soa(struct dlz_bind9_data *state, struct ldb_dn *dn, const char *zone)
{
	const char *attrs[] = { "dnsRecord", NULL };
	struct ldb_result *res;
	struct ldb_message_element *el;
	TALLOC_CTX *tmp_ctx = talloc_new(state);
	int ret, i;

	if (!ldb_dn_add_child_fmt(dn, "DC=@,DC=%s", zone)) {
		talloc_free(tmp_ctx);
		return false;
	}

	ret = ldb_search(state->samdb, tmp_ctx, &res, dn, LDB_SCOPE_BASE,
			 attrs, "objectClass=dnsNode");
	if (ret != LDB_SUCCESS) {
		talloc_free(tmp_ctx);
		return false;
	}

	el = ldb_msg_find_element(res->msgs[0], "dnsRecord");
	if (el == NULL) {
		talloc_free(tmp_ctx);
		return false;
	}
	for (i=0; i<el->num_values; i++) {
		struct dnsp_DnssrvRpcRecord rec;
		enum ndr_err_code ndr_err;

		ndr_err = ndr_pull_struct_blob(&el->values[i], tmp_ctx, &rec,
					       (ndr_pull_flags_fn_t)ndr_pull_dnsp_DnssrvRpcRecord);
		if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
			continue;
		}
		if (rec.wType == DNS_TYPE_SOA) {
			talloc_free(tmp_ctx);
			return true;
		}
	}

	talloc_free(tmp_ctx);
	return false;
}

/*
  configure a writeable zone
 */
_PUBLIC_ isc_result_t dlz_configure(dns_view_t *view, void *dbdata)
{
	struct dlz_bind9_data *state = talloc_get_type_abort(dbdata, struct dlz_bind9_data);
	TALLOC_CTX *tmp_ctx;
	struct ldb_dn *dn;
	int i;

	state->log(ISC_LOG_INFO, "samba dlz_bind9: starting configure");
	if (state->writeable_zone == NULL) {
		state->log(ISC_LOG_INFO, "samba dlz_bind9: no writeable_zone method available");
		return ISC_R_FAILURE;
	}

	tmp_ctx = talloc_new(state);

	for (i=0; zone_prefixes[i]; i++) {
		const char *attrs[] = { "name", NULL };
		int j, ret;
		struct ldb_result *res;

		dn = ldb_dn_copy(tmp_ctx, ldb_get_default_basedn(state->samdb));
		if (dn == NULL) {
			talloc_free(tmp_ctx);
			return ISC_R_NOMEMORY;
		}

		if (!ldb_dn_add_child_fmt(dn, "%s", zone_prefixes[i])) {
			talloc_free(tmp_ctx);
			return ISC_R_NOMEMORY;
		}

		ret = ldb_search(state->samdb, tmp_ctx, &res, dn, LDB_SCOPE_SUBTREE,
				 attrs, "objectClass=dnsZone");
		if (ret != LDB_SUCCESS) {
			continue;
		}

		for (j=0; j<res->count; j++) {
			isc_result_t result;
			const char *zone = ldb_msg_find_attr_as_string(res->msgs[j], "name", NULL);
			if (zone == NULL) {
				continue;
			}
			if (!b9_has_soa(state, dn, zone)) {
				continue;
			}
			result = state->writeable_zone(view, zone);
			if (result != ISC_R_SUCCESS) {
				state->log(ISC_LOG_ERROR, "samba dlz_bind9: Failed to configure zone '%s'",
					   zone);
				talloc_free(tmp_ctx);
				return result;
			}
			state->log(ISC_LOG_INFO, "samba dlz_bind9: configured writeable zone '%s'", zone);
		}
	}

	talloc_free(tmp_ctx);
	return ISC_R_SUCCESS;
}

/*
  authorize a zone update
 */
_PUBLIC_ isc_boolean_t dlz_ssumatch(const char *signer, const char *name, const char *tcpaddr,
				    const char *type, const char *key, uint32_t keydatalen, uint8_t *keydata,
				    void *dbdata)
{
	struct dlz_bind9_data *state = talloc_get_type_abort(dbdata, struct dlz_bind9_data);

	state->log(ISC_LOG_INFO, "samba dlz_bind9: allowing update of signer=%s name=%s tcpaddr=%s type=%s key=%s keydatalen=%u",
		   signer, name, tcpaddr, type, key, keydatalen);
	return true;
}


_PUBLIC_ isc_result_t dlz_addrdataset(const char *name, const char *rdatastr, void *dbdata, void *version)
{
	struct dlz_bind9_data *state = talloc_get_type_abort(dbdata, struct dlz_bind9_data);

	if (version != (void *) &state->transaction_started) {
		return ISC_R_FAILURE;
	}

	state->log(ISC_LOG_INFO, "samba dlz_bind9: adding rdataset %s '%s'", name, rdatastr);

	return ISC_R_SUCCESS;
}

_PUBLIC_ isc_result_t dlz_subrdataset(const char *name, const char *rdatastr, void *dbdata, void *version)
{
	struct dlz_bind9_data *state = talloc_get_type_abort(dbdata, struct dlz_bind9_data);

	if (version != (void *) &state->transaction_started) {
		return ISC_R_FAILURE;
	}

	state->log(ISC_LOG_INFO, "samba dlz_bind9: subtracting rdataset %s '%s'", name, rdatastr);

	return ISC_R_SUCCESS;
}


_PUBLIC_ isc_result_t dlz_delrdataset(const char *name, void *dbdata, void *version)
{
	struct dlz_bind9_data *state = talloc_get_type_abort(dbdata, struct dlz_bind9_data);

	if (version != (void *) &state->transaction_started) {
		return ISC_R_FAILURE;
	}

	state->log(ISC_LOG_INFO, "samba dlz_bind9: deleting rdataset %s", name);

	return ISC_R_SUCCESS;
}