/contrib/bind9/lib/dns/zt.c

  1/*
  2 * Copyright (C) 2004-2007, 2011, 2012  Internet Systems Consortium, Inc. ("ISC")
  3 * Copyright (C) 1999-2002  Internet Software Consortium.
  4 *
  5 * Permission to use, copy, modify, and/or distribute this software for any
  6 * purpose with or without fee is hereby granted, provided that the above
  7 * copyright notice and this permission notice appear in all copies.
  8 *
  9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 11 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
 12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 15 * PERFORMANCE OF THIS SOFTWARE.
 16 */
 17
 18/* $Id$ */
 19
 20/*! \file */
 21
 22#include <config.h>
 23
 24#include <isc/file.h>
 25#include <isc/magic.h>
 26#include <isc/mem.h>
 27#include <isc/string.h>
 28#include <isc/util.h>
 29
 30#include <dns/log.h>
 31#include <dns/name.h>
 32#include <dns/rbt.h>
 33#include <dns/rdataclass.h>
 34#include <dns/result.h>
 35#include <dns/view.h>
 36#include <dns/zone.h>
 37#include <dns/zt.h>
 38
 39struct dns_zt {
 40	/* Unlocked. */
 41	unsigned int		magic;
 42	isc_mem_t		*mctx;
 43	dns_rdataclass_t	rdclass;
 44	isc_rwlock_t		rwlock;
 45	/* Locked by lock. */
 46	isc_uint32_t		references;
 47	dns_rbt_t		*table;
 48};
 49
 50#define ZTMAGIC			ISC_MAGIC('Z', 'T', 'b', 'l')
 51#define VALID_ZT(zt) 		ISC_MAGIC_VALID(zt, ZTMAGIC)
 52
 53static void
 54auto_detach(void *, void *);
 55
 56static isc_result_t
 57load(dns_zone_t *zone, void *uap);
 58
 59static isc_result_t
 60loadnew(dns_zone_t *zone, void *uap);
 61
 62static isc_result_t
 63freezezones(dns_zone_t *zone, void *uap);
 64
 65isc_result_t
 66dns_zt_create(isc_mem_t *mctx, dns_rdataclass_t rdclass, dns_zt_t **ztp)
 67{
 68	dns_zt_t *zt;
 69	isc_result_t result;
 70
 71	REQUIRE(ztp != NULL && *ztp == NULL);
 72
 73	zt = isc_mem_get(mctx, sizeof(*zt));
 74	if (zt == NULL)
 75		return (ISC_R_NOMEMORY);
 76
 77	zt->table = NULL;
 78	result = dns_rbt_create(mctx, auto_detach, zt, &zt->table);
 79	if (result != ISC_R_SUCCESS)
 80		goto cleanup_zt;
 81
 82	result = isc_rwlock_init(&zt->rwlock, 0, 0);
 83	if (result != ISC_R_SUCCESS)
 84		goto cleanup_rbt;
 85
 86	zt->mctx = mctx;
 87	zt->references = 1;
 88	zt->rdclass = rdclass;
 89	zt->magic = ZTMAGIC;
 90	*ztp = zt;
 91
 92	return (ISC_R_SUCCESS);
 93
 94   cleanup_rbt:
 95	dns_rbt_destroy(&zt->table);
 96
 97   cleanup_zt:
 98	isc_mem_put(mctx, zt, sizeof(*zt));
 99
100	return (result);
101}
102
103isc_result_t
104dns_zt_mount(dns_zt_t *zt, dns_zone_t *zone) {
105	isc_result_t result;
106	dns_zone_t *dummy = NULL;
107	dns_name_t *name;
108
109	REQUIRE(VALID_ZT(zt));
110
111	name = dns_zone_getorigin(zone);
112
113	RWLOCK(&zt->rwlock, isc_rwlocktype_write);
114
115	result = dns_rbt_addname(zt->table, name, zone);
116	if (result == ISC_R_SUCCESS)
117		dns_zone_attach(zone, &dummy);
118
119	RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
120
121	return (result);
122}
123
124isc_result_t
125dns_zt_unmount(dns_zt_t *zt, dns_zone_t *zone) {
126	isc_result_t result;
127	dns_name_t *name;
128
129	REQUIRE(VALID_ZT(zt));
130
131	name = dns_zone_getorigin(zone);
132
133	RWLOCK(&zt->rwlock, isc_rwlocktype_write);
134
135	result = dns_rbt_deletename(zt->table, name, ISC_FALSE);
136
137	RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
138
139	return (result);
140}
141
142isc_result_t
143dns_zt_find(dns_zt_t *zt, dns_name_t *name, unsigned int options,
144	    dns_name_t *foundname, dns_zone_t **zonep)
145{
146	isc_result_t result;
147	dns_zone_t *dummy = NULL;
148	unsigned int rbtoptions = 0;
149
150	REQUIRE(VALID_ZT(zt));
151
152	if ((options & DNS_ZTFIND_NOEXACT) != 0)
153		rbtoptions |= DNS_RBTFIND_NOEXACT;
154
155	RWLOCK(&zt->rwlock, isc_rwlocktype_read);
156
157	result = dns_rbt_findname(zt->table, name, rbtoptions, foundname,
158				  (void **) (void*)&dummy);
159	if (result == ISC_R_SUCCESS || result == DNS_R_PARTIALMATCH)
160		dns_zone_attach(dummy, zonep);
161
162	RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
163
164	return (result);
165}
166
167void
168dns_zt_attach(dns_zt_t *zt, dns_zt_t **ztp) {
169
170	REQUIRE(VALID_ZT(zt));
171	REQUIRE(ztp != NULL && *ztp == NULL);
172
173	RWLOCK(&zt->rwlock, isc_rwlocktype_write);
174
175	INSIST(zt->references > 0);
176	zt->references++;
177	INSIST(zt->references != 0);
178
179	RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
180
181	*ztp = zt;
182}
183
184static isc_result_t
185flush(dns_zone_t *zone, void *uap) {
186	UNUSED(uap);
187	return (dns_zone_flush(zone));
188}
189
190static void
191zt_flushanddetach(dns_zt_t **ztp, isc_boolean_t need_flush) {
192	isc_boolean_t destroy = ISC_FALSE;
193	dns_zt_t *zt;
194
195	REQUIRE(ztp != NULL && VALID_ZT(*ztp));
196
197	zt = *ztp;
198
199	RWLOCK(&zt->rwlock, isc_rwlocktype_write);
200
201	INSIST(zt->references > 0);
202	zt->references--;
203	if (zt->references == 0)
204		destroy = ISC_TRUE;
205
206	RWUNLOCK(&zt->rwlock, isc_rwlocktype_write);
207
208	if (destroy) {
209		if (need_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_put(zt->mctx, zt, sizeof(*zt));
215	}
216
217	*ztp = NULL;
218}
219
220void
221dns_zt_flushanddetach(dns_zt_t **ztp) {
222	zt_flushanddetach(ztp, ISC_TRUE);
223}
224
225void
226dns_zt_detach(dns_zt_t **ztp) {
227	zt_flushanddetach(ztp, ISC_FALSE);
228}
229
230isc_result_t
231dns_zt_load(dns_zt_t *zt, isc_boolean_t stop) {
232	isc_result_t result;
233
234	REQUIRE(VALID_ZT(zt));
235
236	RWLOCK(&zt->rwlock, isc_rwlocktype_read);
237	result = dns_zt_apply(zt, stop, load, NULL);
238	RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
239	return (result);
240}
241
242static isc_result_t
243load(dns_zone_t *zone, void *uap) {
244	isc_result_t result;
245	UNUSED(uap);
246	result = dns_zone_load(zone);
247	if (result == DNS_R_CONTINUE || result == DNS_R_UPTODATE)
248		result = ISC_R_SUCCESS;
249	return (result);
250}
251
252isc_result_t
253dns_zt_loadnew(dns_zt_t *zt, isc_boolean_t stop) {
254	isc_result_t result;
255
256	REQUIRE(VALID_ZT(zt));
257
258	RWLOCK(&zt->rwlock, isc_rwlocktype_read);
259	result = dns_zt_apply(zt, stop, loadnew, NULL);
260	RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
261	return (result);
262}
263
264static isc_result_t
265loadnew(dns_zone_t *zone, void *uap) {
266	isc_result_t result;
267	UNUSED(uap);
268	result = dns_zone_loadnew(zone);
269	if (result == DNS_R_CONTINUE || result == DNS_R_UPTODATE ||
270	    result == DNS_R_DYNAMIC)
271		result = ISC_R_SUCCESS;
272	return (result);
273}
274
275isc_result_t
276dns_zt_freezezones(dns_zt_t *zt, isc_boolean_t freeze) {
277	isc_result_t result, tresult;
278
279	REQUIRE(VALID_ZT(zt));
280
281	RWLOCK(&zt->rwlock, isc_rwlocktype_read);
282	result = dns_zt_apply2(zt, ISC_FALSE, &tresult, freezezones, &freeze);
283	RWUNLOCK(&zt->rwlock, isc_rwlocktype_read);
284	return ((result == ISC_R_SUCCESS) ? tresult : result);
285}
286
287static isc_result_t
288freezezones(dns_zone_t *zone, void *uap) {
289	isc_boolean_t freeze = *(isc_boolean_t *)uap;
290	isc_boolean_t frozen;
291	isc_result_t result = ISC_R_SUCCESS;
292	char classstr[DNS_RDATACLASS_FORMATSIZE];
293	char zonename[DNS_NAME_FORMATSIZE];
294	dns_view_t *view;
295	char *journal;
296	const char *vname;
297	const char *sep;
298	int level;
299
300	if (dns_zone_gettype(zone) != dns_zone_master)
301		return (ISC_R_SUCCESS);
302
303	frozen = dns_zone_getupdatedisabled(zone);
304	if (freeze) {
305		if (frozen)
306			result = DNS_R_FROZEN;
307		if (result == ISC_R_SUCCESS)
308			result = dns_zone_flush(zone);
309		if (result == ISC_R_SUCCESS) {
310			journal = dns_zone_getjournal(zone);
311			if (journal != NULL)
312				(void)isc_file_remove(journal);
313		}
314	} else {
315		if (frozen) {
316			result = dns_zone_load(zone);
317			if (result == DNS_R_CONTINUE ||
318			    result == DNS_R_UPTODATE)
319				result = ISC_R_SUCCESS;
320		}
321	}
322	if (result == ISC_R_SUCCESS)
323		dns_zone_setupdatedisabled(zone, freeze);
324	view = dns_zone_getview(zone);
325	if (strcmp(view->name, "_bind") == 0 ||
326	    strcmp(view->name, "_default") == 0)
327	{
328		vname = "";
329		sep = "";
330	} else {
331		vname = view->name;
332		sep = " ";
333	}
334	dns_rdataclass_format(dns_zone_getclass(zone), classstr,
335			      sizeof(classstr));
336	dns_name_format(dns_zone_getorigin(zone), zonename, sizeof(zonename));
337	level = (result != ISC_R_SUCCESS) ? ISC_LOG_ERROR : ISC_LOG_DEBUG(1);
338	isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_ZONE,
339		      level, "%s zone '%s/%s'%s%s: %s",
340		      freeze ? "freezing" : "thawing",
341		      zonename, classstr, sep, vname,
342		      isc_result_totext(result));
343	return (result);
344}
345
346isc_result_t
347dns_zt_apply(dns_zt_t *zt, isc_boolean_t stop,
348	     isc_result_t (*action)(dns_zone_t *, void *), void *uap)
349{
350	return (dns_zt_apply2(zt, stop, NULL, action, uap));
351}
352
353isc_result_t
354dns_zt_apply2(dns_zt_t *zt, isc_boolean_t stop, isc_result_t *sub,
355	      isc_result_t (*action)(dns_zone_t *, void *), void *uap)
356{
357	dns_rbtnode_t *node;
358	dns_rbtnodechain_t chain;
359	isc_result_t result, tresult = ISC_R_SUCCESS;
360	dns_zone_t *zone;
361
362	REQUIRE(VALID_ZT(zt));
363	REQUIRE(action != NULL);
364
365	dns_rbtnodechain_init(&chain, zt->mctx);
366	result = dns_rbtnodechain_first(&chain, zt->table, NULL, NULL);
367	if (result == ISC_R_NOTFOUND) {
368		/*
369		 * The tree is empty.
370		 */
371		result = ISC_R_NOMORE;
372	}
373	while (result == DNS_R_NEWORIGIN || result == ISC_R_SUCCESS) {
374		result = dns_rbtnodechain_current(&chain, NULL, NULL,
375						  &node);
376		if (result == ISC_R_SUCCESS) {
377			zone = node->data;
378			if (zone != NULL)
379				result = (action)(zone, uap);
380			if (result != ISC_R_SUCCESS && stop) {
381				tresult = result;
382				goto cleanup;	/* don't break */
383			} else if (result != ISC_R_SUCCESS &&
384				   tresult == ISC_R_SUCCESS)
385				tresult = result;
386		}
387		result = dns_rbtnodechain_next(&chain, NULL, NULL);
388	}
389	if (result == ISC_R_NOMORE)
390		result = ISC_R_SUCCESS;
391
392 cleanup:
393	dns_rbtnodechain_invalidate(&chain);
394	if (sub != NULL)
395		*sub = tresult;
396
397	return (result);
398}
399
400/***
401 *** Private
402 ***/
403
404static void
405auto_detach(void *data, void *arg) {
406	dns_zone_t *zone = data;
407
408	UNUSED(arg);
409
410	dns_zone_detach(&zone);
411}