summaryrefslogtreecommitdiffstats
path: root/source4/wrepl_server/wrepl_scavenging.c
blob: b601f8658afe1fb6c0b575c798860317d82ae616 (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
/* 
   Unix SMB/CIFS implementation.
   
   WINS Replication server
   
   Copyright (C) Stefan Metzmacher	2005
   
   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 "librpc/gen_ndr/ndr_winsrepl.h"
#include "wrepl_server/wrepl_server.h"
#include "nbt_server/wins/winsdb.h"
#include "ldb/include/ldb.h"
#include "ldb/include/ldb_errors.h"
#include "system/time.h"
#include "smbd/service_task.h"
#include "lib/messaging/irpc.h"
#include "librpc/gen_ndr/ndr_irpc.h"
#include "librpc/gen_ndr/ndr_nbt.h"
#include "param/param.h"

const char *wreplsrv_owner_filter(struct wreplsrv_service *service,
				  TALLOC_CTX *mem_ctx,
				  const char *wins_owner)
{
	if (strcmp(wins_owner, service->wins_db->local_owner) == 0) {
		return talloc_asprintf(mem_ctx, "(|(winsOwner=%s)(winsOwner=0.0.0.0))",
				       wins_owner);
	}

	return talloc_asprintf(mem_ctx, "(&(winsOwner=%s)(!(winsOwner=0.0.0.0)))",
			       wins_owner);
}

static NTSTATUS wreplsrv_scavenging_owned_records(struct wreplsrv_service *service, TALLOC_CTX *tmp_mem)
{
	NTSTATUS status;
	struct winsdb_record *rec = NULL;
	struct ldb_result *res = NULL;
	const char *owner_filter;
	const char *filter;
	unsigned int i;
	int ret;
	time_t now = time(NULL);
	const char *now_timestr;
	const char *action;
	const char *old_state=NULL;
	const char *new_state=NULL;
	uint32_t modify_flags;
	bool modify_record;
	bool delete_record;
	bool delete_tombstones;
	struct timeval tombstone_extra_time;
	const char *local_owner = service->wins_db->local_owner;
	bool propagate = lp_parm_bool(service->task->lp_ctx, NULL, "wreplsrv", "propagate name releases", false);

	now_timestr = ldb_timestring(tmp_mem, now);
	NT_STATUS_HAVE_NO_MEMORY(now_timestr);
	owner_filter = wreplsrv_owner_filter(service, tmp_mem, local_owner);
	NT_STATUS_HAVE_NO_MEMORY(owner_filter);
	filter = talloc_asprintf(tmp_mem,
				 "(&%s(objectClass=winsRecord)"
				 "(expireTime<=%s))",
				 owner_filter, now_timestr);
	NT_STATUS_HAVE_NO_MEMORY(filter);
	ret = ldb_search(service->wins_db->ldb, tmp_mem, &res, NULL, LDB_SCOPE_SUBTREE, NULL, "%s", filter);
	if (ret != LDB_SUCCESS) return NT_STATUS_INTERNAL_DB_CORRUPTION;
	DEBUG(10,("WINS scavenging: filter '%s' count %d\n", filter, res->count));

	tombstone_extra_time = timeval_add(&service->startup_time,
					   service->config.tombstone_extra_timeout,
					   0);
	delete_tombstones = timeval_expired(&tombstone_extra_time);

	for (i=0; i < res->count; i++) {
		bool has_replicas = false;

		/*
		 * we pass '0' as 'now' here,
		 * because we want to get the raw timestamps which are in the DB
		 */
		status = winsdb_record(service->wins_db, res->msgs[i], tmp_mem, 0, &rec);
		NT_STATUS_NOT_OK_RETURN(status);
		talloc_free(res->msgs[i]);

		modify_flags	= 0;
		modify_record	= false;
		delete_record	= false;

		switch (rec->state) {
		case WREPL_STATE_ACTIVE:
			old_state	= "active";
			if (rec->is_static) {
				/*
				 *we store it again, so that it won't appear
				 * in the scavenging the next time
				 */
				old_state	= "active(static)";
				new_state	= "active(static)";
				modify_flags	= 0;
				modify_record	= true;
				break;
			}
			if (rec->type != WREPL_TYPE_SGROUP || !propagate) {
				new_state	= "released";
				rec->state	= WREPL_STATE_RELEASED;
				rec->expire_time= service->config.tombstone_interval + now;
				modify_flags	= 0;
				modify_record	= true;
				break;
			}
			/* check if there's any replica address */
			for (i=0;rec->addresses[i];i++) {
				if (strcmp(rec->addresses[i]->wins_owner, local_owner) != 0) {
					has_replicas = true;
					rec->addresses[i]->expire_time= service->config.renew_interval + now;
				}
			}
			if (has_replicas) {
				/* if it has replica addresses propagate them */
				new_state	= "active(propagated)";
				rec->state	= WREPL_STATE_ACTIVE;
				rec->expire_time= service->config.renew_interval + now;
				modify_flags	= WINSDB_FLAG_ALLOC_VERSION | WINSDB_FLAG_TAKE_OWNERSHIP;
				modify_record	= true;
				break;
			}
			/*
			 * if it doesn't have replica addresses, make it a tombstone,
			 * so that the released owned addresses are propagated
			 */
			new_state	= "tombstone";
			rec->state	= WREPL_STATE_TOMBSTONE;
			rec->expire_time= time(NULL) +
					  service->config.tombstone_interval +
					  service->config.tombstone_timeout;
			modify_flags	= WINSDB_FLAG_ALLOC_VERSION | WINSDB_FLAG_TAKE_OWNERSHIP;
			modify_record	= true;
			break;

		case WREPL_STATE_RELEASED:
			old_state	= "released";
			new_state	= "tombstone";
			rec->state	= WREPL_STATE_TOMBSTONE;
			rec->expire_time= service->config.tombstone_timeout + now;
			modify_flags	= WINSDB_FLAG_ALLOC_VERSION | WINSDB_FLAG_TAKE_OWNERSHIP;
			modify_record	= true;
			break;

		case WREPL_STATE_TOMBSTONE:
			old_state	= "tombstone";
			new_state	= "tombstone";
			if (!delete_tombstones) break;
			new_state	= "deleted";
			delete_record = true;
			break;

		case WREPL_STATE_RESERVED:
			DEBUG(0,("%s: corrupted record: %s\n",
				__location__, nbt_name_string(rec, rec->name)));
			return NT_STATUS_INTERNAL_DB_CORRUPTION;
		}

		if (modify_record) {
			action = "modify";
			ret = winsdb_modify(service->wins_db, rec, modify_flags);
		} else if (delete_record) {
			action = "delete";
			ret = winsdb_delete(service->wins_db, rec);
		} else {
			action = "skip";
			ret = NBT_RCODE_OK;
		}

		if (ret != NBT_RCODE_OK) {
			DEBUG(2,("WINS scavenging: failed to %s name %s (owned:%s -> owned:%s): error:%u\n",
				action, nbt_name_string(rec, rec->name), old_state, new_state, ret));
		} else {
			DEBUG(4,("WINS scavenging: %s name: %s (owned:%s -> owned:%s)\n",
				action, nbt_name_string(rec, rec->name), old_state, new_state));
		}

		talloc_free(rec);
	}

	return NT_STATUS_OK;
}

static NTSTATUS wreplsrv_scavenging_replica_non_active_records(struct wreplsrv_service *service, TALLOC_CTX *tmp_mem)
{
	NTSTATUS status;
	struct winsdb_record *rec = NULL;
	struct ldb_result *res = NULL;
	const char *owner_filter;
	const char *filter;
	unsigned int i;
	int ret;
	time_t now = time(NULL);
	const char *now_timestr;
	const char *action;
	const char *old_state=NULL;
	const char *new_state=NULL;
	uint32_t modify_flags;
	bool modify_record;
	bool delete_record;
	bool delete_tombstones;
	struct timeval tombstone_extra_time;

	now_timestr = ldb_timestring(tmp_mem, now);
	NT_STATUS_HAVE_NO_MEMORY(now_timestr);
	owner_filter = wreplsrv_owner_filter(service, tmp_mem,
					     service->wins_db->local_owner);
	NT_STATUS_HAVE_NO_MEMORY(owner_filter);
	filter = talloc_asprintf(tmp_mem,
				 "(&(!%s)(objectClass=winsRecord)"
				 "(!(recordState=%u))(expireTime<=%s))",
				 owner_filter, WREPL_STATE_ACTIVE, now_timestr);
	NT_STATUS_HAVE_NO_MEMORY(filter);
	ret = ldb_search(service->wins_db->ldb, tmp_mem, &res, NULL, LDB_SCOPE_SUBTREE, NULL, "%s", filter);
	if (ret != LDB_SUCCESS) return NT_STATUS_INTERNAL_DB_CORRUPTION;
	DEBUG(10,("WINS scavenging: filter '%s' count %d\n", filter, res->count));

	tombstone_extra_time = timeval_add(&service->startup_time,
					   service->config.tombstone_extra_timeout,
					   0);
	delete_tombstones = timeval_expired(&tombstone_extra_time);

	for (i=0; i < res->count; i++) {
		/*
		 * we pass '0' as 'now' here,
		 * because we want to get the raw timestamps which are in the DB
		 */
		status = winsdb_record(service->wins_db, res->msgs[i], tmp_mem, 0, &rec);
		NT_STATUS_NOT_OK_RETURN(status);
		talloc_free(res->msgs[i]);

		modify_flags	= 0;
		modify_record	= false;
		delete_record	= false;

		switch (rec->state) {
		case WREPL_STATE_ACTIVE:
			DEBUG(0,("%s: corrupted record: %s\n",
				__location__, nbt_name_string(rec, rec->name)));
			return NT_STATUS_INTERNAL_DB_CORRUPTION;

		case WREPL_STATE_RELEASED:
			old_state	= "released";
			new_state	= "tombstone";
			rec->state	= WREPL_STATE_TOMBSTONE;
			rec->expire_time= service->config.tombstone_timeout + now;
			modify_flags	= 0;
			modify_record	= true;
			break;

		case WREPL_STATE_TOMBSTONE:
			old_state	= "tombstone";
			new_state	= "tombstone";
			if (!delete_tombstones) break;
			new_state	= "deleted";
			delete_record = true;
			break;

		case WREPL_STATE_RESERVED:
			DEBUG(0,("%s: corrupted record: %s\n",
				__location__, nbt_name_string(rec, rec->name)));
			return NT_STATUS_INTERNAL_DB_CORRUPTION;
		}

		if (modify_record) {
			action = "modify";
			ret = winsdb_modify(service->wins_db, rec, modify_flags);
		} else if (delete_record) {
			action = "delete";
			ret = winsdb_delete(service->wins_db, rec);
		} else {
			action = "skip";
			ret = NBT_RCODE_OK;
		}

		if (ret != NBT_RCODE_OK) {
			DEBUG(2,("WINS scavenging: failed to %s name %s (replica:%s -> replica:%s): error:%u\n",
				action, nbt_name_string(rec, rec->name), old_state, new_state, ret));
		} else {
			DEBUG(4,("WINS scavenging: %s name: %s (replica:%s -> replica:%s)\n",
				action, nbt_name_string(rec, rec->name), old_state, new_state));
		}

		talloc_free(rec);
	}

	return NT_STATUS_OK;
}

struct verify_state {
	struct messaging_context *msg_ctx;
	struct wreplsrv_service *service;
	struct winsdb_record *rec;
	struct nbtd_proxy_wins_challenge r;
};

static void verify_handler(struct irpc_request *ireq)
{
	struct verify_state *s = talloc_get_type(ireq->async.private_data,
				 struct verify_state);
	struct winsdb_record *rec = s->rec;
	const char *action;
	const char *old_state = "active";
	const char *new_state = "active";
	const char *new_owner = "replica";
	uint32_t modify_flags = 0;
	bool modify_record = false;
	bool delete_record = false;
	bool different = false;
	int ret;
	NTSTATUS status;
	uint32_t i, j;

	/*
	 * - if the name isn't present anymore remove our record
	 * - if the name is found and not a normal group check if the addresses match,
	 *   - if they don't match remove the record
	 *   - if they match do nothing
	 * - if an error happens do nothing
	 */
	status = irpc_call_recv(ireq);
	if (NT_STATUS_EQUAL(NT_STATUS_OBJECT_NAME_NOT_FOUND, status)) {
		delete_record = true;
		new_state = "deleted";
	} else if (NT_STATUS_IS_OK(status) && rec->type != WREPL_TYPE_GROUP) {
		for (i=0; i < s->r.out.num_addrs; i++) {
			bool found = false;
			for (j=0; rec->addresses[j]; j++) {
				if (strcmp(s->r.out.addrs[i].addr, rec->addresses[j]->address) == 0) {
					found = true;
					break;
				}
			}
			if (!found) {
				different = true;
				break;
			}
		}
	} else if (NT_STATUS_IS_OK(status) && rec->type == WREPL_TYPE_GROUP) {
		if (s->r.out.num_addrs != 1 || strcmp(s->r.out.addrs[0].addr, "255.255.255.255") != 0) {
			different = true;
		}
	}

	if (different) {
		/*
		 * if the reply from the owning wins server has different addresses
		 * then take the ownership of the record and make it a tombstone
		 * this will then hopefully replicated to the original owner of the record
		 * which will then propagate it's own record, so that the current record will
		 * be replicated to to us
		 */
		DEBUG(2,("WINS scavenging: replica %s verify got different addresses from winsserver: %s: tombstoning record\n",
			nbt_name_string(rec, rec->name), rec->wins_owner));

		rec->state	= WREPL_STATE_TOMBSTONE;
		rec->expire_time= time(NULL) + s->service->config.tombstone_timeout;
		for (i=0; rec->addresses[i]; i++) {
			rec->addresses[i]->expire_time = rec->expire_time;
		}
		modify_record	= true;
		modify_flags	= WINSDB_FLAG_ALLOC_VERSION | WINSDB_FLAG_TAKE_OWNERSHIP;
		new_state	= "tombstone";
		new_owner	= "owned";
	} else if (NT_STATUS_IS_OK(status)) {
		/* if the addresses are the same, just update the timestamps */
		rec->expire_time = time(NULL) + s->service->config.verify_interval;
		for (i=0; rec->addresses[i]; i++) {
			rec->addresses[i]->expire_time = rec->expire_time;
		}
		modify_record	= true;
		modify_flags	= 0;
		new_state	= "active";
	}

	if (modify_record) {
		action = "modify";
		ret = winsdb_modify(s->service->wins_db, rec, modify_flags);
	} else if (delete_record) {
		action = "delete";
		ret = winsdb_delete(s->service->wins_db, rec);
	} else {
		action = "skip";
		ret = NBT_RCODE_OK;
	}

	if (ret != NBT_RCODE_OK) {
		DEBUG(2,("WINS scavenging: failed to %s name %s (replica:%s -> %s:%s): error:%u\n",
			action, nbt_name_string(rec, rec->name), old_state, new_owner, new_state, ret));
	} else {
		DEBUG(4,("WINS scavenging: %s name: %s (replica:%s -> %s:%s): %s: %s\n",
			action, nbt_name_string(rec, rec->name), old_state, new_owner, new_state,
			rec->wins_owner, nt_errstr(status)));
	}

	talloc_free(s);
}

static NTSTATUS wreplsrv_scavenging_replica_active_records(struct wreplsrv_service *service, TALLOC_CTX *tmp_mem)
{
	NTSTATUS status;
	struct winsdb_record *rec = NULL;
	struct ldb_result *res = NULL;
	const char *owner_filter;
	const char *filter;
	unsigned int i;
	int ret;
	time_t now = time(NULL);
	const char *now_timestr;
	struct irpc_request *ireq;
	struct verify_state *s;
	struct server_id *nbt_servers;

	nbt_servers = irpc_servers_byname(service->task->msg_ctx, tmp_mem, "nbt_server");
	if ((nbt_servers == NULL) || (nbt_servers[0].id == 0)) {
		return NT_STATUS_INTERNAL_ERROR;
	}

	now_timestr = ldb_timestring(tmp_mem, now);
	NT_STATUS_HAVE_NO_MEMORY(now_timestr);
	owner_filter = wreplsrv_owner_filter(service, tmp_mem,
					     service->wins_db->local_owner);
	NT_STATUS_HAVE_NO_MEMORY(owner_filter);
	filter = talloc_asprintf(tmp_mem,
				 "(&(!%s)(objectClass=winsRecord)"
				 "(recordState=%u)(expireTime<=%s))",
				 owner_filter, WREPL_STATE_ACTIVE, now_timestr);
	NT_STATUS_HAVE_NO_MEMORY(filter);
	ret = ldb_search(service->wins_db->ldb, tmp_mem, &res, NULL, LDB_SCOPE_SUBTREE, NULL, "%s", filter);
	if (ret != LDB_SUCCESS) return NT_STATUS_INTERNAL_DB_CORRUPTION;
	DEBUG(10,("WINS scavenging: filter '%s' count %d\n", filter, res->count));

	for (i=0; i < res->count; i++) {
		/*
		 * we pass '0' as 'now' here,
		 * because we want to get the raw timestamps which are in the DB
		 */
		status = winsdb_record(service->wins_db, res->msgs[i], tmp_mem, 0, &rec);
		NT_STATUS_NOT_OK_RETURN(status);
		talloc_free(res->msgs[i]);

		if (rec->state != WREPL_STATE_ACTIVE) {
			DEBUG(0,("%s: corrupted record: %s\n",
				__location__, nbt_name_string(rec, rec->name)));
			return NT_STATUS_INTERNAL_DB_CORRUPTION;
		}

		/* 
		 * ask the owning wins server if the record still exists,
		 * if not delete the record
		 *
		 * TODO: NOTE: this is a simpliefied version, to verify that
		 *             a record still exist, I assume that w2k3 uses
		 *             DCERPC calls or some WINSREPL packets for this,
		 *             but we use a wins name query
		 */
		DEBUG(2,("ask wins server '%s' if '%s' with version_id:%llu still exists\n",
			 rec->wins_owner, nbt_name_string(rec, rec->name), 
			 (unsigned long long)rec->version));

		s = talloc_zero(tmp_mem, struct verify_state);
		NT_STATUS_HAVE_NO_MEMORY(s);
		s->msg_ctx	= service->task->msg_ctx;
		s->service	= service;
		s->rec		= talloc_steal(s, rec);

		s->r.in.name		= *rec->name;
		s->r.in.num_addrs	= 1;
		s->r.in.addrs		= talloc_array(s, struct nbtd_proxy_wins_addr, s->r.in.num_addrs);
		NT_STATUS_HAVE_NO_MEMORY(s->r.in.addrs);
		/* TODO: fix pidl to handle inline ipv4address arrays */
		s->r.in.addrs[0].addr	= rec->wins_owner;

		ireq = IRPC_CALL_SEND(s->msg_ctx, nbt_servers[0],
				      irpc, NBTD_PROXY_WINS_CHALLENGE,
				      &s->r, s);
		NT_STATUS_HAVE_NO_MEMORY(ireq);

		ireq->async.fn		= verify_handler;
		ireq->async.private_data= s;

		talloc_steal(service, s);
	}

	return NT_STATUS_OK;
}

NTSTATUS wreplsrv_scavenging_run(struct wreplsrv_service *service)
{
	NTSTATUS status;
	TALLOC_CTX *tmp_mem;
	bool skip_first_run = false;

	if (!timeval_expired(&service->scavenging.next_run)) {
		return NT_STATUS_OK;
	}

	if (timeval_is_zero(&service->scavenging.next_run)) {
		skip_first_run = true;
	}

	service->scavenging.next_run = timeval_current_ofs(service->config.scavenging_interval, 0);
	status = wreplsrv_periodic_schedule(service, service->config.scavenging_interval);
	NT_STATUS_NOT_OK_RETURN(status);

	/*
	 * if it's the first time this functions is called (startup)
	 * the next_run is zero, in this case we should not do scavenging
	 */
	if (skip_first_run) {
		return NT_STATUS_OK;
	}

	if (service->scavenging.processing) {
		return NT_STATUS_OK;
	}

	DEBUG(2,("wreplsrv_scavenging_run(): start\n"));

	tmp_mem = talloc_new(service);
	NT_STATUS_HAVE_NO_MEMORY(tmp_mem);
	service->scavenging.processing = true;
	status = wreplsrv_scavenging_owned_records(service,tmp_mem);
	service->scavenging.processing = false;
	talloc_free(tmp_mem);
	NT_STATUS_NOT_OK_RETURN(status);

	tmp_mem = talloc_new(service);	
	NT_STATUS_HAVE_NO_MEMORY(tmp_mem);
	service->scavenging.processing = true;
	status = wreplsrv_scavenging_replica_non_active_records(service, tmp_mem);
	service->scavenging.processing = false;
	talloc_free(tmp_mem);
	NT_STATUS_NOT_OK_RETURN(status);

	tmp_mem = talloc_new(service);
	NT_STATUS_HAVE_NO_MEMORY(tmp_mem);
	service->scavenging.processing = true;
	status = wreplsrv_scavenging_replica_active_records(service, tmp_mem);
	service->scavenging.processing = false;
	talloc_free(tmp_mem);
	NT_STATUS_NOT_OK_RETURN(status);

	DEBUG(2,("wreplsrv_scavenging_run(): end\n"));

	return NT_STATUS_OK;
}