1 /* $NetBSD: zt.c,v 1.8 2015/07/08 17:28:59 christos Exp $ */
2
3 /*
4 * Copyright (C) 2004-2007, 2011-2015 Internet Systems Consortium, Inc. ("ISC")
5 * Copyright (C) 1999-2002 Internet Software Consortium.
6 *
7 * Permission to use, copy, modify, and/or distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
12 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
13 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
14 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
15 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
16 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
17 * PERFORMANCE OF THIS SOFTWARE.
18 */
19
20 /* Id */
21
22 /*! \file */
23
24 #include <config.h>
25
26 #include <isc/file.h>
27 #include <isc/magic.h>
28 #include <isc/mem.h>
29 #include <isc/string.h>
30 #include <isc/task.h>
31 #include <isc/util.h>
32
33 #include <dns/log.h>
34 #include <dns/name.h>
35 #include <dns/rbt.h>
36 #include <dns/rdataclass.h>
37 #include <dns/result.h>
38 #include <dns/view.h>
39 #include <dns/zone.h>
40 #include <dns/zt.h>
41
42 struct dns_zt {
43 /* Unlocked. */
44 unsigned int magic;
45 isc_mem_t *mctx;
46 dns_rdataclass_t rdclass;
47 isc_rwlock_t rwlock;
48 dns_zt_allloaded_t loaddone;
49 void * loaddone_arg;
50 /* Locked by lock. */
51 isc_boolean_t flush;
52 isc_uint32_t references;
53 unsigned int loads_pending;
54 dns_rbt_t *table;
55 };
56
57 #define ZTMAGIC ISC_MAGIC('Z', 'T', 'b', 'l')
58 #define VALID_ZT(zt) ISC_MAGIC_VALID(zt, ZTMAGIC)
59
60 static void
61 auto_detach(void *, void *);
62
63 static isc_result_t
64 load(dns_zone_t *zone, void *uap);
65
66 static isc_result_t
67 asyncload(dns_zone_t *zone, void *callback);
68
69 static isc_result_t
70 loadnew(dns_zone_t *zone, void *uap);
71
72 static isc_result_t
73 freezezones(dns_zone_t *zone, void *uap);
74
75 static isc_result_t
76 doneloading(dns_zt_t *zt, dns_zone_t *zone, isc_task_t *task);
77
78 isc_result_t
dns_zt_create(isc_mem_t * mctx,dns_rdataclass_t rdclass,dns_zt_t ** ztp)79 dns_zt_create(isc_mem_t *mctx, dns_rdataclass_t rdclass, dns_zt_t **ztp) {
80 dns_zt_t *zt;
81 isc_result_t result;
82
83 REQUIRE(ztp != NULL && *ztp == NULL);
84
85 zt = isc_mem_get(mctx, sizeof(*zt));
86 if (zt == NULL)
87 return (ISC_R_NOMEMORY);
88
89 zt->table = NULL;
90 result = dns_rbt_create(mctx, auto_detach, zt, &zt->table);
91 if (result != ISC_R_SUCCESS)
92 goto cleanup_zt;
93
94 result = isc_rwlock_init(&zt->rwlock, 0, 0);
95 if (result != ISC_R_SUCCESS)
96 goto cleanup_rbt;
97
98 zt->mctx = NULL;
99 isc_mem_attach(mctx, &zt->mctx);
100 zt->references = 1;
101 zt->flush = ISC_FALSE;
102 zt->rdclass = rdclass;
103 zt->magic = ZTMAGIC;
104 zt->loaddone = NULL;
105 zt->loaddone_arg = NULL;
106 zt->loads_pending = 0;
107 *ztp = zt;
108
109 return (ISC_R_SUCCESS);
110
111 cleanup_rbt:
112 dns_rbt_destroy(&zt->table);
113
114 cleanup_zt:
115 isc_mem_put(mctx, zt, sizeof(*zt));
116
117 return (result);
118 }
119
120 isc_result_t
dns_zt_mount(dns_zt_t * zt,dns_zone_t * zone)121 dns_zt_mount(dns_zt_t *zt, dns_zone_t *zone) {
122 isc_result_t result;
123 dns_zone_t *dummy = NULL;
124 dns_name_t *name;
125
126 REQUIRE(VALID_ZT(zt));
127
128 name = dns_zone_getorigin(zone);
129
130 RWLOCK(&zt->rwlock, isc_rwlocktype_write);
131
132 result = dns_rbt_addname(zt->table, name, zone);
133 if (result == ISC_R_SUCCESS)
134 dns_zone_attach(zone, &dummy);
135
136 RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
137
138 return (result);
139 }
140
141 isc_result_t
dns_zt_unmount(dns_zt_t * zt,dns_zone_t * zone)142 dns_zt_unmount(dns_zt_t *zt, dns_zone_t *zone) {
143 isc_result_t result;
144 dns_name_t *name;
145
146 REQUIRE(VALID_ZT(zt));
147
148 name = dns_zone_getorigin(zone);
149
150 RWLOCK(&zt->rwlock, isc_rwlocktype_write);
151
152 result = dns_rbt_deletename(zt->table, name, ISC_FALSE);
153
154 RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
155
156 return (result);
157 }
158
159 isc_result_t
dns_zt_find(dns_zt_t * zt,dns_name_t * name,unsigned int options,dns_name_t * foundname,dns_zone_t ** zonep)160 dns_zt_find(dns_zt_t *zt, dns_name_t *name, unsigned int options,
161 dns_name_t *foundname, dns_zone_t **zonep)
162 {
163 isc_result_t result;
164 dns_zone_t *dummy = NULL;
165 unsigned int rbtoptions = 0;
166
167 REQUIRE(VALID_ZT(zt));
168
169 if ((options & DNS_ZTFIND_NOEXACT) != 0)
170 rbtoptions |= DNS_RBTFIND_NOEXACT;
171
172 RWLOCK(&zt->rwlock, isc_rwlocktype_read);
173
174 result = dns_rbt_findname(zt->table, name, rbtoptions, foundname,
175 (void **) (void*)&dummy);
176 if (result == ISC_R_SUCCESS || result == DNS_R_PARTIALMATCH)
177 dns_zone_attach(dummy, zonep);
178
179 RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
180
181 return (result);
182 }
183
184 void
dns_zt_attach(dns_zt_t * zt,dns_zt_t ** ztp)185 dns_zt_attach(dns_zt_t *zt, dns_zt_t **ztp) {
186
187 REQUIRE(VALID_ZT(zt));
188 REQUIRE(ztp != NULL && *ztp == NULL);
189
190 RWLOCK(&zt->rwlock, isc_rwlocktype_write);
191
192 INSIST(zt->references > 0);
193 zt->references++;
194 INSIST(zt->references != 0);
195
196 RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
197
198 *ztp = zt;
199 }
200
201 static isc_result_t
flush(dns_zone_t * zone,void * uap)202 flush(dns_zone_t *zone, void *uap) {
203 UNUSED(uap);
204 return (dns_zone_flush(zone));
205 }
206
207 static void
zt_destroy(dns_zt_t * zt)208 zt_destroy(dns_zt_t *zt) {
209 if (zt->flush)
210 (void)dns_zt_apply(zt, ISC_FALSE, flush, NULL);
211 dns_rbt_destroy(&zt->table);
212 isc_rwlock_destroy(&zt->rwlock);
213 zt->magic = 0;
214 isc_mem_putanddetach(&zt->mctx, zt, sizeof(*zt));
215 }
216
217 static void
zt_flushanddetach(dns_zt_t ** ztp,isc_boolean_t need_flush)218 zt_flushanddetach(dns_zt_t **ztp, isc_boolean_t need_flush) {
219 isc_boolean_t destroy = ISC_FALSE;
220 dns_zt_t *zt;
221
222 REQUIRE(ztp != NULL && VALID_ZT(*ztp));
223
224 zt = *ztp;
225
226 RWLOCK(&zt->rwlock, isc_rwlocktype_write);
227
228 INSIST(zt->references > 0);
229 zt->references--;
230 if (zt->references == 0)
231 destroy = ISC_TRUE;
232 if (need_flush)
233 zt->flush = ISC_TRUE;
234
235 RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
236
237 if (destroy)
238 zt_destroy(zt);
239
240 *ztp = NULL;
241 }
242
243 void
dns_zt_flushanddetach(dns_zt_t ** ztp)244 dns_zt_flushanddetach(dns_zt_t **ztp) {
245 zt_flushanddetach(ztp, ISC_TRUE);
246 }
247
248 void
dns_zt_detach(dns_zt_t ** ztp)249 dns_zt_detach(dns_zt_t **ztp) {
250 zt_flushanddetach(ztp, ISC_FALSE);
251 }
252
253 isc_result_t
dns_zt_load(dns_zt_t * zt,isc_boolean_t stop)254 dns_zt_load(dns_zt_t *zt, isc_boolean_t stop) {
255 isc_result_t result;
256
257 REQUIRE(VALID_ZT(zt));
258
259 RWLOCK(&zt->rwlock, isc_rwlocktype_read);
260 result = dns_zt_apply(zt, stop, load, NULL);
261 RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
262 return (result);
263 }
264
265 static isc_result_t
load(dns_zone_t * zone,void * uap)266 load(dns_zone_t *zone, void *uap) {
267 isc_result_t result;
268 UNUSED(uap);
269
270 result = dns_zone_load(zone);
271 if (result == DNS_R_CONTINUE || result == DNS_R_UPTODATE)
272 result = ISC_R_SUCCESS;
273
274 return (result);
275 }
276
277 isc_result_t
dns_zt_asyncload(dns_zt_t * zt,dns_zt_allloaded_t alldone,void * arg)278 dns_zt_asyncload(dns_zt_t *zt, dns_zt_allloaded_t alldone, void *arg) {
279 isc_result_t result;
280 static dns_zt_zoneloaded_t dl = doneloading;
281 int pending;
282
283 REQUIRE(VALID_ZT(zt));
284
285 RWLOCK(&zt->rwlock, isc_rwlocktype_write);
286
287 INSIST(zt->loads_pending == 0);
288 result = dns_zt_apply2(zt, ISC_FALSE, NULL, asyncload, &dl);
289
290 pending = zt->loads_pending;
291 if (pending != 0) {
292 zt->loaddone = alldone;
293 zt->loaddone_arg = arg;
294 }
295
296 RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
297
298 if (pending == 0)
299 alldone(arg);
300
301 return (result);
302 }
303
304 /*
305 * Initiates asynchronous loading of zone 'zone'. 'callback' is a
306 * pointer to a function which will be used to inform the caller when
307 * the zone loading is complete.
308 */
309 static isc_result_t
asyncload(dns_zone_t * zone,void * callback)310 asyncload(dns_zone_t *zone, void *callback) {
311 isc_result_t result;
312 dns_zt_zoneloaded_t *loaded = callback;
313 dns_zt_t *zt;
314
315 REQUIRE(zone != NULL);
316 zt = dns_zone_getview(zone)->zonetable;
317 INSIST(VALID_ZT(zt));
318
319 INSIST(zt->references > 0);
320 zt->references++;
321 zt->loads_pending++;
322
323 result = dns_zone_asyncload(zone, *loaded, zt);
324 if (result != ISC_R_SUCCESS) {
325 zt->references--;
326 zt->loads_pending--;
327 INSIST(zt->references > 0);
328 }
329 return (ISC_R_SUCCESS);
330 }
331
332 isc_result_t
dns_zt_loadnew(dns_zt_t * zt,isc_boolean_t stop)333 dns_zt_loadnew(dns_zt_t *zt, isc_boolean_t stop) {
334 isc_result_t result;
335
336 REQUIRE(VALID_ZT(zt));
337
338 RWLOCK(&zt->rwlock, isc_rwlocktype_read);
339 result = dns_zt_apply(zt, stop, loadnew, NULL);
340 RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
341 return (result);
342 }
343
344 static isc_result_t
loadnew(dns_zone_t * zone,void * uap)345 loadnew(dns_zone_t *zone, void *uap) {
346 isc_result_t result;
347 UNUSED(uap);
348
349 result = dns_zone_loadnew(zone);
350 if (result == DNS_R_CONTINUE || result == DNS_R_UPTODATE ||
351 result == DNS_R_DYNAMIC)
352 result = ISC_R_SUCCESS;
353 return (result);
354 }
355
356 isc_result_t
dns_zt_freezezones(dns_zt_t * zt,isc_boolean_t freeze)357 dns_zt_freezezones(dns_zt_t *zt, isc_boolean_t freeze) {
358 isc_result_t result, tresult;
359
360 REQUIRE(VALID_ZT(zt));
361
362 RWLOCK(&zt->rwlock, isc_rwlocktype_read);
363 result = dns_zt_apply2(zt, ISC_FALSE, &tresult, freezezones, &freeze);
364 RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
365 if (tresult == ISC_R_NOTFOUND)
366 tresult = ISC_R_SUCCESS;
367 return ((result == ISC_R_SUCCESS) ? tresult : result);
368 }
369
370 static isc_result_t
freezezones(dns_zone_t * zone,void * uap)371 freezezones(dns_zone_t *zone, void *uap) {
372 isc_boolean_t freeze = *(isc_boolean_t *)uap;
373 isc_boolean_t frozen;
374 isc_result_t result = ISC_R_SUCCESS;
375 char classstr[DNS_RDATACLASS_FORMATSIZE];
376 char zonename[DNS_NAME_FORMATSIZE];
377 dns_zone_t *raw = NULL;
378 dns_view_t *view;
379 const char *vname;
380 const char *sep;
381 int level;
382
383 dns_zone_getraw(zone, &raw);
384 if (raw != NULL)
385 zone = raw;
386 if (dns_zone_gettype(zone) != dns_zone_master) {
387 if (raw != NULL)
388 dns_zone_detach(&raw);
389 return (ISC_R_SUCCESS);
390 }
391 if (!dns_zone_isdynamic(zone, ISC_TRUE)) {
392 if (raw != NULL)
393 dns_zone_detach(&raw);
394 return (ISC_R_SUCCESS);
395 }
396
397 frozen = dns_zone_getupdatedisabled(zone);
398 if (freeze) {
399 if (frozen)
400 result = DNS_R_FROZEN;
401 if (result == ISC_R_SUCCESS)
402 result = dns_zone_flush(zone);
403 if (result == ISC_R_SUCCESS)
404 dns_zone_setupdatedisabled(zone, freeze);
405 } else {
406 if (frozen) {
407 result = dns_zone_loadandthaw(zone);
408 if (result == DNS_R_CONTINUE ||
409 result == DNS_R_UPTODATE)
410 result = ISC_R_SUCCESS;
411 }
412 }
413 view = dns_zone_getview(zone);
414 if (strcmp(view->name, "_bind") == 0 ||
415 strcmp(view->name, "_default") == 0)
416 {
417 vname = "";
418 sep = "";
419 } else {
420 vname = view->name;
421 sep = " ";
422 }
423 dns_rdataclass_format(dns_zone_getclass(zone), classstr,
424 sizeof(classstr));
425 dns_name_format(dns_zone_getorigin(zone), zonename, sizeof(zonename));
426 level = (result != ISC_R_SUCCESS) ? ISC_LOG_ERROR : ISC_LOG_DEBUG(1);
427 isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_ZONE,
428 level, "%s zone '%s/%s'%s%s: %s",
429 freeze ? "freezing" : "thawing",
430 zonename, classstr, sep, vname,
431 isc_result_totext(result));
432 if (raw != NULL)
433 dns_zone_detach(&raw);
434 return (result);
435 }
436
437 isc_result_t
dns_zt_apply(dns_zt_t * zt,isc_boolean_t stop,isc_result_t (* action)(dns_zone_t *,void *),void * uap)438 dns_zt_apply(dns_zt_t *zt, isc_boolean_t stop,
439 isc_result_t (*action)(dns_zone_t *, void *), void *uap)
440 {
441 return (dns_zt_apply2(zt, stop, NULL, action, uap));
442 }
443
444 isc_result_t
dns_zt_apply2(dns_zt_t * zt,isc_boolean_t stop,isc_result_t * sub,isc_result_t (* action)(dns_zone_t *,void *),void * uap)445 dns_zt_apply2(dns_zt_t *zt, isc_boolean_t stop, isc_result_t *sub,
446 isc_result_t (*action)(dns_zone_t *, void *), void *uap)
447 {
448 dns_rbtnode_t *node;
449 dns_rbtnodechain_t chain;
450 isc_result_t result, tresult = ISC_R_SUCCESS;
451 dns_zone_t *zone;
452
453 REQUIRE(VALID_ZT(zt));
454 REQUIRE(action != NULL);
455
456 dns_rbtnodechain_init(&chain, zt->mctx);
457 result = dns_rbtnodechain_first(&chain, zt->table, NULL, NULL);
458 if (result == ISC_R_NOTFOUND) {
459 /*
460 * The tree is empty.
461 */
462 tresult = result;
463 result = ISC_R_NOMORE;
464 }
465 while (result == DNS_R_NEWORIGIN || result == ISC_R_SUCCESS) {
466 result = dns_rbtnodechain_current(&chain, NULL, NULL,
467 &node);
468 if (result == ISC_R_SUCCESS) {
469 zone = node->data;
470 if (zone != NULL)
471 result = (action)(zone, uap);
472 if (result != ISC_R_SUCCESS && stop) {
473 tresult = result;
474 goto cleanup; /* don't break */
475 } else if (result != ISC_R_SUCCESS &&
476 tresult == ISC_R_SUCCESS)
477 tresult = result;
478 }
479 result = dns_rbtnodechain_next(&chain, NULL, NULL);
480 }
481 if (result == ISC_R_NOMORE)
482 result = ISC_R_SUCCESS;
483
484 cleanup:
485 dns_rbtnodechain_invalidate(&chain);
486 if (sub != NULL)
487 *sub = tresult;
488
489 return (result);
490 }
491
492 /*
493 * Decrement the loads_pending counter; when counter reaches
494 * zero, call the loaddone callback that was initially set by
495 * dns_zt_asyncload().
496 */
497 static isc_result_t
doneloading(dns_zt_t * zt,dns_zone_t * zone,isc_task_t * task)498 doneloading(dns_zt_t *zt, dns_zone_t *zone, isc_task_t *task) {
499 isc_boolean_t destroy = ISC_FALSE;
500 dns_zt_allloaded_t alldone = NULL;
501 void *arg = NULL;
502
503 UNUSED(zone);
504 UNUSED(task);
505
506 REQUIRE(VALID_ZT(zt));
507
508 RWLOCK(&zt->rwlock, isc_rwlocktype_write);
509 INSIST(zt->loads_pending != 0);
510 INSIST(zt->references != 0);
511 zt->references--;
512 if (zt->references == 0)
513 destroy = ISC_TRUE;
514 zt->loads_pending--;
515 if (zt->loads_pending == 0) {
516 alldone = zt->loaddone;
517 arg = zt->loaddone_arg;
518 zt->loaddone = NULL;
519 zt->loaddone_arg = NULL;
520 }
521 RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
522
523 if (alldone != NULL)
524 alldone(arg);
525
526 if (destroy)
527 zt_destroy(zt);
528
529 return (ISC_R_SUCCESS);
530 }
531
532 /***
533 *** Private
534 ***/
535
536 static void
auto_detach(void * data,void * arg)537 auto_detach(void *data, void *arg) {
538 dns_zone_t *zone = data;
539
540 UNUSED(arg);
541 dns_zone_detach(&zone);
542 }
543