xref: /netbsd-src/external/mpl/bind/dist/lib/dns/sdlz.c (revision bcda20f65a8566e103791ec395f7f499ef322704)
1 /*	$NetBSD: sdlz.c,v 1.14 2025/01/26 16:25:25 christos Exp $	*/
2 
3 /*
4  * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
5  *
6  * SPDX-License-Identifier: MPL-2.0 AND ISC
7  *
8  * This Source Code Form is subject to the terms of the Mozilla Public
9  * License, v. 2.0. If a copy of the MPL was not distributed with this
10  * file, you can obtain one at https://mozilla.org/MPL/2.0/.
11  *
12  * See the COPYRIGHT file distributed with this work for additional
13  * information regarding copyright ownership.
14  */
15 
16 /*
17  * Copyright (C) 2002 Stichting NLnet, Netherlands, stichting@nlnet.nl.
18  *
19  * Permission to use, copy, modify, and distribute this software for any
20  * purpose with or without fee is hereby granted, provided that the
21  * above copyright notice and this permission notice appear in all
22  * copies.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS" AND STICHTING NLNET
25  * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
27  * STICHTING NLNET BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
28  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
29  * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
30  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE
31  * USE OR PERFORMANCE OF THIS SOFTWARE.
32  *
33  * The development of Dynamically Loadable Zones (DLZ) for Bind 9 was
34  * conceived and contributed by Rob Butler.
35  *
36  * Permission to use, copy, modify, and distribute this software for any
37  * purpose with or without fee is hereby granted, provided that the
38  * above copyright notice and this permission notice appear in all
39  * copies.
40  *
41  * THE SOFTWARE IS PROVIDED "AS IS" AND ROB BUTLER
42  * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
44  * ROB BUTLER BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
45  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
46  * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
47  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE
48  * USE OR PERFORMANCE OF THIS SOFTWARE.
49  */
50 
51 /*! \file */
52 
53 #include <inttypes.h>
54 #include <stdbool.h>
55 #include <string.h>
56 
57 #include <isc/ascii.h>
58 #include <isc/buffer.h>
59 #include <isc/lex.h>
60 #include <isc/log.h>
61 #include <isc/magic.h>
62 #include <isc/mem.h>
63 #include <isc/once.h>
64 #include <isc/region.h>
65 #include <isc/result.h>
66 #include <isc/rwlock.h>
67 #include <isc/string.h>
68 #include <isc/util.h>
69 
70 #include <dns/callbacks.h>
71 #include <dns/db.h>
72 #include <dns/dbiterator.h>
73 #include <dns/dlz.h>
74 #include <dns/fixedname.h>
75 #include <dns/log.h>
76 #include <dns/master.h>
77 #include <dns/rdata.h>
78 #include <dns/rdatalist.h>
79 #include <dns/rdataset.h>
80 #include <dns/rdatasetiter.h>
81 #include <dns/rdatatype.h>
82 #include <dns/sdlz.h>
83 #include <dns/types.h>
84 
85 /*
86  * Private Types
87  */
88 
89 struct dns_sdlzimplementation {
90 	const dns_sdlzmethods_t *methods;
91 	isc_mem_t *mctx;
92 	void *driverarg;
93 	unsigned int flags;
94 	isc_mutex_t driverlock;
95 	dns_dlzimplementation_t *dlz_imp;
96 };
97 
98 struct dns_sdlz_db {
99 	/* Unlocked */
100 	dns_db_t common;
101 	void *dbdata;
102 	dns_sdlzimplementation_t *dlzimp;
103 
104 	/* Locked */
105 	dns_dbversion_t *future_version;
106 	int dummy_version;
107 };
108 
109 struct dns_sdlzlookup {
110 	/* Unlocked */
111 	unsigned int magic;
112 	dns_sdlz_db_t *sdlz;
113 	ISC_LIST(dns_rdatalist_t) lists;
114 	ISC_LIST(isc_buffer_t) buffers;
115 	dns_name_t *name;
116 	ISC_LINK(dns_sdlzlookup_t) link;
117 	dns_rdatacallbacks_t callbacks;
118 
119 	/* Atomic */
120 	isc_refcount_t references;
121 };
122 
123 typedef struct dns_sdlzlookup dns_sdlznode_t;
124 
125 struct dns_sdlzallnodes {
126 	dns_dbiterator_t common;
127 	ISC_LIST(dns_sdlznode_t) nodelist;
128 	dns_sdlznode_t *current;
129 	dns_sdlznode_t *origin;
130 };
131 
132 typedef dns_sdlzallnodes_t sdlz_dbiterator_t;
133 
134 typedef struct sdlz_rdatasetiter {
135 	dns_rdatasetiter_t common;
136 	dns_rdatalist_t *current;
137 } sdlz_rdatasetiter_t;
138 
139 #define SDLZDB_MAGIC ISC_MAGIC('D', 'L', 'Z', 'S')
140 
141 /*
142  * Note that "impmagic" is not the first four bytes of the struct, so
143  * ISC_MAGIC_VALID cannot be used.
144  */
145 
146 #define VALID_SDLZDB(sdlzdb) \
147 	((sdlzdb) != NULL && (sdlzdb)->common.impmagic == SDLZDB_MAGIC)
148 
149 #define SDLZLOOKUP_MAGIC	ISC_MAGIC('D', 'L', 'Z', 'L')
150 #define VALID_SDLZLOOKUP(sdlzl) ISC_MAGIC_VALID(sdlzl, SDLZLOOKUP_MAGIC)
151 #define VALID_SDLZNODE(sdlzn)	VALID_SDLZLOOKUP(sdlzn)
152 
153 /* These values are taken from RFC 1537 */
154 #define SDLZ_DEFAULT_REFRESH 28800U  /* 8 hours */
155 #define SDLZ_DEFAULT_RETRY   7200U   /* 2 hours */
156 #define SDLZ_DEFAULT_EXPIRE  604800U /* 7 days */
157 #define SDLZ_DEFAULT_MINIMUM 86400U  /* 1 day */
158 
159 /* This is a reasonable value */
160 #define SDLZ_DEFAULT_TTL (60 * 60 * 24)
161 
162 #ifdef __COVERITY__
163 #define MAYBE_LOCK(imp)	  LOCK(&imp->driverlock)
164 #define MAYBE_UNLOCK(imp) UNLOCK(&imp->driverlock)
165 #else /* ifdef __COVERITY__ */
166 #define MAYBE_LOCK(imp)                                     \
167 	do {                                                \
168 		unsigned int flags = imp->flags;            \
169 		if ((flags & DNS_SDLZFLAG_THREADSAFE) == 0) \
170 			LOCK(&imp->driverlock);             \
171 	} while (0)
172 
173 #define MAYBE_UNLOCK(imp)                                   \
174 	do {                                                \
175 		unsigned int flags = imp->flags;            \
176 		if ((flags & DNS_SDLZFLAG_THREADSAFE) == 0) \
177 			UNLOCK(&imp->driverlock);           \
178 	} while (0)
179 #endif /* ifdef __COVERITY__ */
180 
181 /*
182  * Forward references.
183  */
184 static isc_result_t
185 getnodedata(dns_db_t *db, const dns_name_t *name, bool create,
186 	    unsigned int options, dns_clientinfomethods_t *methods,
187 	    dns_clientinfo_t *clientinfo, dns_dbnode_t **nodep);
188 
189 static void
190 list_tordataset(dns_rdatalist_t *rdatalist, dns_db_t *db, dns_dbnode_t *node,
191 		dns_rdataset_t *rdataset);
192 
193 static void
194 detachnode(dns_db_t *db, dns_dbnode_t **targetp DNS__DB_FLARG);
195 
196 static void
197 dbiterator_destroy(dns_dbiterator_t **iteratorp DNS__DB_FLARG);
198 static isc_result_t
199 dbiterator_first(dns_dbiterator_t *iterator DNS__DB_FLARG);
200 static isc_result_t
201 dbiterator_last(dns_dbiterator_t *iterator DNS__DB_FLARG);
202 static isc_result_t
203 dbiterator_seek(dns_dbiterator_t *iterator,
204 		const dns_name_t *name DNS__DB_FLARG);
205 static isc_result_t
206 dbiterator_prev(dns_dbiterator_t *iterator DNS__DB_FLARG);
207 static isc_result_t
208 dbiterator_next(dns_dbiterator_t *iterator DNS__DB_FLARG);
209 static isc_result_t
210 dbiterator_current(dns_dbiterator_t *iterator, dns_dbnode_t **nodep,
211 		   dns_name_t *name DNS__DB_FLARG);
212 static isc_result_t
213 dbiterator_pause(dns_dbiterator_t *iterator);
214 static isc_result_t
215 dbiterator_origin(dns_dbiterator_t *iterator, dns_name_t *name);
216 
217 static dns_dbiteratormethods_t dbiterator_methods = {
218 	dbiterator_destroy, dbiterator_first, dbiterator_last,
219 	dbiterator_seek,    dbiterator_prev,  dbiterator_next,
220 	dbiterator_current, dbiterator_pause, dbiterator_origin
221 };
222 
223 /*
224  * Utility functions
225  */
226 
227 /*
228  * Log a message at the given level
229  */
230 static void
231 sdlz_log(int level, const char *fmt, ...) {
232 	va_list ap;
233 	va_start(ap, fmt);
234 	isc_log_vwrite(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ,
235 		       ISC_LOG_DEBUG(level), fmt, ap);
236 	va_end(ap);
237 }
238 
239 static unsigned int
240 initial_size(const char *data) {
241 	unsigned int len = (strlen(data) / 64) + 1;
242 	return len * 64 + 64;
243 }
244 
245 /*
246  * Rdataset Iterator Methods. These methods were "borrowed" from the SDB
247  * driver interface.  See the SDB driver interface documentation for more info.
248  */
249 
250 static void
251 rdatasetiter_destroy(dns_rdatasetiter_t **iteratorp DNS__DB_FLARG) {
252 	sdlz_rdatasetiter_t *sdlziterator = (sdlz_rdatasetiter_t *)(*iteratorp);
253 
254 	detachnode(sdlziterator->common.db,
255 		   &sdlziterator->common.node DNS__DB_FLARG_PASS);
256 	isc_mem_put(sdlziterator->common.db->mctx, sdlziterator,
257 		    sizeof(sdlz_rdatasetiter_t));
258 	*iteratorp = NULL;
259 }
260 
261 static isc_result_t
262 rdatasetiter_first(dns_rdatasetiter_t *iterator DNS__DB_FLARG) {
263 	sdlz_rdatasetiter_t *sdlziterator = (sdlz_rdatasetiter_t *)iterator;
264 	dns_sdlznode_t *sdlznode = (dns_sdlznode_t *)iterator->node;
265 
266 	if (ISC_LIST_EMPTY(sdlznode->lists)) {
267 		return ISC_R_NOMORE;
268 	}
269 	sdlziterator->current = ISC_LIST_HEAD(sdlznode->lists);
270 	return ISC_R_SUCCESS;
271 }
272 
273 static isc_result_t
274 rdatasetiter_next(dns_rdatasetiter_t *iterator DNS__DB_FLARG) {
275 	sdlz_rdatasetiter_t *sdlziterator = (sdlz_rdatasetiter_t *)iterator;
276 
277 	sdlziterator->current = ISC_LIST_NEXT(sdlziterator->current, link);
278 	if (sdlziterator->current == NULL) {
279 		return ISC_R_NOMORE;
280 	} else {
281 		return ISC_R_SUCCESS;
282 	}
283 }
284 
285 static void
286 rdatasetiter_current(dns_rdatasetiter_t *iterator,
287 		     dns_rdataset_t *rdataset DNS__DB_FLARG) {
288 	sdlz_rdatasetiter_t *sdlziterator = (sdlz_rdatasetiter_t *)iterator;
289 
290 	list_tordataset(sdlziterator->current, iterator->db, iterator->node,
291 			rdataset);
292 }
293 
294 static dns_rdatasetitermethods_t rdatasetiter_methods = {
295 	rdatasetiter_destroy, rdatasetiter_first, rdatasetiter_next,
296 	rdatasetiter_current
297 };
298 
299 /*
300  * DB routines. These methods were "borrowed" from the SDB driver interface.
301  * See the SDB driver interface documentation for more info.
302  */
303 
304 static void
305 destroy(dns_db_t *db) {
306 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
307 
308 	sdlz->common.magic = 0;
309 	sdlz->common.impmagic = 0;
310 
311 	dns_name_free(&sdlz->common.origin, sdlz->common.mctx);
312 
313 	isc_refcount_destroy(&sdlz->common.references);
314 	isc_mem_putanddetach(&sdlz->common.mctx, sdlz, sizeof(dns_sdlz_db_t));
315 }
316 
317 static void
318 currentversion(dns_db_t *db, dns_dbversion_t **versionp) {
319 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
320 	REQUIRE(VALID_SDLZDB(sdlz));
321 	REQUIRE(versionp != NULL && *versionp == NULL);
322 
323 	*versionp = (void *)&sdlz->dummy_version;
324 	return;
325 }
326 
327 static isc_result_t
328 newversion(dns_db_t *db, dns_dbversion_t **versionp) {
329 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
330 	char origin[DNS_NAME_MAXTEXT + 1];
331 	isc_result_t result;
332 
333 	REQUIRE(VALID_SDLZDB(sdlz));
334 
335 	if (sdlz->dlzimp->methods->newversion == NULL) {
336 		return ISC_R_NOTIMPLEMENTED;
337 	}
338 
339 	dns_name_format(&sdlz->common.origin, origin, sizeof(origin));
340 
341 	result = sdlz->dlzimp->methods->newversion(
342 		origin, sdlz->dlzimp->driverarg, sdlz->dbdata, versionp);
343 	if (result != ISC_R_SUCCESS) {
344 		sdlz_log(ISC_LOG_ERROR,
345 			 "sdlz newversion on origin %s failed : %s", origin,
346 			 isc_result_totext(result));
347 		return result;
348 	}
349 
350 	sdlz->future_version = *versionp;
351 	return ISC_R_SUCCESS;
352 }
353 
354 static void
355 attachversion(dns_db_t *db, dns_dbversion_t *source,
356 	      dns_dbversion_t **targetp) {
357 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
358 
359 	REQUIRE(VALID_SDLZDB(sdlz));
360 	REQUIRE(source != NULL && source == (void *)&sdlz->dummy_version);
361 
362 	*targetp = source;
363 }
364 
365 static void
366 closeversion(dns_db_t *db, dns_dbversion_t **versionp,
367 	     bool commit DNS__DB_FLARG) {
368 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
369 	char origin[DNS_NAME_MAXTEXT + 1];
370 
371 	REQUIRE(VALID_SDLZDB(sdlz));
372 	REQUIRE(versionp != NULL);
373 
374 	if (*versionp == (void *)&sdlz->dummy_version) {
375 		*versionp = NULL;
376 		return;
377 	}
378 
379 	REQUIRE(*versionp == sdlz->future_version);
380 	REQUIRE(sdlz->dlzimp->methods->closeversion != NULL);
381 
382 	dns_name_format(&sdlz->common.origin, origin, sizeof(origin));
383 
384 	sdlz->dlzimp->methods->closeversion(origin, commit,
385 					    sdlz->dlzimp->driverarg,
386 					    sdlz->dbdata, versionp);
387 	if (*versionp != NULL) {
388 		sdlz_log(ISC_LOG_ERROR, "sdlz closeversion on origin %s failed",
389 			 origin);
390 	}
391 
392 	sdlz->future_version = NULL;
393 }
394 
395 static isc_result_t
396 createnode(dns_sdlz_db_t *sdlz, dns_sdlznode_t **nodep) {
397 	dns_sdlznode_t *node;
398 
399 	node = isc_mem_get(sdlz->common.mctx, sizeof(dns_sdlznode_t));
400 
401 	node->sdlz = NULL;
402 	dns_db_attach((dns_db_t *)sdlz, (dns_db_t **)&node->sdlz);
403 	ISC_LIST_INIT(node->lists);
404 	ISC_LIST_INIT(node->buffers);
405 	ISC_LINK_INIT(node, link);
406 	node->name = NULL;
407 	dns_rdatacallbacks_init(&node->callbacks);
408 
409 	isc_refcount_init(&node->references, 1);
410 	node->magic = SDLZLOOKUP_MAGIC;
411 
412 	*nodep = node;
413 	return ISC_R_SUCCESS;
414 }
415 
416 static void
417 destroynode(dns_sdlznode_t *node) {
418 	dns_rdatalist_t *list;
419 	dns_rdata_t *rdata;
420 	isc_buffer_t *b;
421 	dns_sdlz_db_t *sdlz;
422 	dns_db_t *db;
423 	isc_mem_t *mctx;
424 
425 	isc_refcount_destroy(&node->references);
426 
427 	sdlz = node->sdlz;
428 	mctx = sdlz->common.mctx;
429 
430 	while (!ISC_LIST_EMPTY(node->lists)) {
431 		list = ISC_LIST_HEAD(node->lists);
432 		while (!ISC_LIST_EMPTY(list->rdata)) {
433 			rdata = ISC_LIST_HEAD(list->rdata);
434 			ISC_LIST_UNLINK(list->rdata, rdata, link);
435 			isc_mem_put(mctx, rdata, sizeof(dns_rdata_t));
436 		}
437 		ISC_LIST_UNLINK(node->lists, list, link);
438 		isc_mem_put(mctx, list, sizeof(dns_rdatalist_t));
439 	}
440 
441 	while (!ISC_LIST_EMPTY(node->buffers)) {
442 		b = ISC_LIST_HEAD(node->buffers);
443 		ISC_LIST_UNLINK(node->buffers, b, link);
444 		isc_buffer_free(&b);
445 	}
446 
447 	if (node->name != NULL) {
448 		dns_name_free(node->name, mctx);
449 		isc_mem_put(mctx, node->name, sizeof(dns_name_t));
450 	}
451 
452 	node->magic = 0;
453 	isc_mem_put(mctx, node, sizeof(dns_sdlznode_t));
454 	db = &sdlz->common;
455 	dns_db_detach(&db);
456 }
457 
458 static isc_result_t
459 getnodedata(dns_db_t *db, const dns_name_t *name, bool create,
460 	    unsigned int options, dns_clientinfomethods_t *methods,
461 	    dns_clientinfo_t *clientinfo, dns_dbnode_t **nodep) {
462 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
463 	dns_sdlznode_t *node = NULL;
464 	isc_result_t result;
465 	isc_buffer_t b;
466 	char namestr[DNS_NAME_MAXTEXT + 1];
467 	isc_buffer_t b2;
468 	char zonestr[DNS_NAME_MAXTEXT + 1];
469 	bool isorigin;
470 	dns_sdlzauthorityfunc_t authority;
471 
472 	REQUIRE(VALID_SDLZDB(sdlz));
473 	REQUIRE(nodep != NULL && *nodep == NULL);
474 
475 	if (sdlz->dlzimp->methods->newversion == NULL) {
476 		REQUIRE(!create);
477 	}
478 
479 	isc_buffer_init(&b, namestr, sizeof(namestr));
480 	if ((sdlz->dlzimp->flags & DNS_SDLZFLAG_RELATIVEOWNER) != 0) {
481 		dns_name_t relname;
482 		unsigned int labels;
483 
484 		labels = dns_name_countlabels(name) -
485 			 dns_name_countlabels(&sdlz->common.origin);
486 		dns_name_init(&relname, NULL);
487 		dns_name_getlabelsequence(name, 0, labels, &relname);
488 		result = dns_name_totext(&relname, DNS_NAME_OMITFINALDOT, &b);
489 		if (result != ISC_R_SUCCESS) {
490 			return result;
491 		}
492 	} else {
493 		result = dns_name_totext(name, DNS_NAME_OMITFINALDOT, &b);
494 		if (result != ISC_R_SUCCESS) {
495 			return result;
496 		}
497 	}
498 	isc_buffer_putuint8(&b, 0);
499 
500 	isc_buffer_init(&b2, zonestr, sizeof(zonestr));
501 	result = dns_name_totext(&sdlz->common.origin, DNS_NAME_OMITFINALDOT,
502 				 &b2);
503 	if (result != ISC_R_SUCCESS) {
504 		return result;
505 	}
506 	isc_buffer_putuint8(&b2, 0);
507 
508 	result = createnode(sdlz, &node);
509 	if (result != ISC_R_SUCCESS) {
510 		return result;
511 	}
512 
513 	isorigin = dns_name_equal(name, &sdlz->common.origin);
514 
515 	/* make sure strings are always lowercase */
516 	isc_ascii_strtolower(zonestr);
517 	isc_ascii_strtolower(namestr);
518 
519 	MAYBE_LOCK(sdlz->dlzimp);
520 
521 	/* try to lookup the host (namestr) */
522 	result = sdlz->dlzimp->methods->lookup(
523 		zonestr, namestr, sdlz->dlzimp->driverarg, sdlz->dbdata, node,
524 		methods, clientinfo);
525 
526 	/*
527 	 * If the name was not found and DNS_DBFIND_NOWILD is not
528 	 * set, then we try to find a wildcard entry.
529 	 *
530 	 * If DNS_DBFIND_NOZONECUT is set and there are multiple
531 	 * levels between the host and the zone origin, we also look
532 	 * for wildcards at each level.
533 	 */
534 	if (result == ISC_R_NOTFOUND && !create &&
535 	    (options & DNS_DBFIND_NOWILD) == 0)
536 	{
537 		unsigned int i, dlabels, nlabels;
538 
539 		nlabels = dns_name_countlabels(name);
540 		dlabels = nlabels - dns_name_countlabels(&sdlz->common.origin);
541 		for (i = 0; i < dlabels; i++) {
542 			char wildstr[DNS_NAME_MAXTEXT + 1];
543 			dns_fixedname_t fixed;
544 			const dns_name_t *wild;
545 
546 			dns_fixedname_init(&fixed);
547 			if (i == dlabels - 1) {
548 				wild = dns_wildcardname;
549 			} else {
550 				dns_name_t *fname;
551 				fname = dns_fixedname_name(&fixed);
552 				dns_name_getlabelsequence(
553 					name, i + 1, dlabels - i - 1, fname);
554 				result = dns_name_concatenate(
555 					dns_wildcardname, fname, fname, NULL);
556 				if (result != ISC_R_SUCCESS) {
557 					MAYBE_UNLOCK(sdlz->dlzimp);
558 					return result;
559 				}
560 				wild = fname;
561 			}
562 
563 			isc_buffer_init(&b, wildstr, sizeof(wildstr));
564 			result = dns_name_totext(wild, DNS_NAME_OMITFINALDOT,
565 						 &b);
566 			if (result != ISC_R_SUCCESS) {
567 				MAYBE_UNLOCK(sdlz->dlzimp);
568 				return result;
569 			}
570 			isc_buffer_putuint8(&b, 0);
571 
572 			result = sdlz->dlzimp->methods->lookup(
573 				zonestr, wildstr, sdlz->dlzimp->driverarg,
574 				sdlz->dbdata, node, methods, clientinfo);
575 			if (result == ISC_R_SUCCESS) {
576 				break;
577 			}
578 		}
579 	}
580 
581 	MAYBE_UNLOCK(sdlz->dlzimp);
582 
583 	if (result == ISC_R_NOTFOUND && (isorigin || create)) {
584 		result = ISC_R_SUCCESS;
585 	}
586 
587 	if (result != ISC_R_SUCCESS) {
588 		isc_refcount_decrementz(&node->references);
589 		destroynode(node);
590 		return result;
591 	}
592 
593 	if (isorigin && sdlz->dlzimp->methods->authority != NULL) {
594 		MAYBE_LOCK(sdlz->dlzimp);
595 		authority = sdlz->dlzimp->methods->authority;
596 		result = (*authority)(zonestr, sdlz->dlzimp->driverarg,
597 				      sdlz->dbdata, node);
598 		MAYBE_UNLOCK(sdlz->dlzimp);
599 		if (result != ISC_R_SUCCESS && result != ISC_R_NOTIMPLEMENTED) {
600 			isc_refcount_decrementz(&node->references);
601 			destroynode(node);
602 			return result;
603 		}
604 	}
605 
606 	if (node->name == NULL) {
607 		node->name = isc_mem_get(sdlz->common.mctx, sizeof(dns_name_t));
608 		dns_name_init(node->name, NULL);
609 		dns_name_dup(name, sdlz->common.mctx, node->name);
610 	}
611 
612 	*nodep = node;
613 	return ISC_R_SUCCESS;
614 }
615 
616 static isc_result_t
617 findnodeext(dns_db_t *db, const dns_name_t *name, bool create,
618 	    dns_clientinfomethods_t *methods, dns_clientinfo_t *clientinfo,
619 	    dns_dbnode_t **nodep DNS__DB_FLARG) {
620 	return getnodedata(db, name, create, 0, methods, clientinfo, nodep);
621 }
622 
623 static isc_result_t
624 findnode(dns_db_t *db, const dns_name_t *name, bool create,
625 	 dns_dbnode_t **nodep DNS__DB_FLARG) {
626 	return getnodedata(db, name, create, 0, NULL, NULL, nodep);
627 }
628 
629 static void
630 attachnode(dns_db_t *db, dns_dbnode_t *source,
631 	   dns_dbnode_t **targetp DNS__DB_FLARG) {
632 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
633 	dns_sdlznode_t *node = (dns_sdlznode_t *)source;
634 	uint_fast32_t refs;
635 
636 	REQUIRE(VALID_SDLZDB(sdlz));
637 
638 	UNUSED(sdlz);
639 
640 	refs = isc_refcount_increment(&node->references);
641 #if DNS_DB_NODETRACE
642 	fprintf(stderr, "incr:node:%s:%s:%u:%p->references = %" PRIuFAST32 "\n",
643 		func, file, line, node, refs + 1);
644 #else
645 	UNUSED(refs);
646 #endif
647 
648 	*targetp = source;
649 }
650 
651 static void
652 detachnode(dns_db_t *db, dns_dbnode_t **targetp DNS__DB_FLARG) {
653 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
654 	dns_sdlznode_t *node;
655 	uint_fast32_t refs;
656 
657 	REQUIRE(VALID_SDLZDB(sdlz));
658 	REQUIRE(targetp != NULL && *targetp != NULL);
659 
660 	UNUSED(sdlz);
661 
662 	node = (dns_sdlznode_t *)(*targetp);
663 	*targetp = NULL;
664 
665 	refs = isc_refcount_decrement(&node->references);
666 #if DNS_DB_NODETRACE
667 	fprintf(stderr, "decr:node:%s:%s:%u:%p->references = %" PRIuFAST32 "\n",
668 		func, file, line, node, refs - 1);
669 #else
670 	UNUSED(refs);
671 #endif
672 
673 	if (refs == 1) {
674 		destroynode(node);
675 	}
676 }
677 
678 static isc_result_t
679 createiterator(dns_db_t *db, unsigned int options,
680 	       dns_dbiterator_t **iteratorp) {
681 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
682 	sdlz_dbiterator_t *sdlziter;
683 	isc_result_t result;
684 	isc_buffer_t b;
685 	char zonestr[DNS_NAME_MAXTEXT + 1];
686 
687 	REQUIRE(VALID_SDLZDB(sdlz));
688 
689 	if (sdlz->dlzimp->methods->allnodes == NULL) {
690 		return ISC_R_NOTIMPLEMENTED;
691 	}
692 
693 	if ((options & DNS_DB_NSEC3ONLY) != 0 ||
694 	    (options & DNS_DB_NONSEC3) != 0)
695 	{
696 		return ISC_R_NOTIMPLEMENTED;
697 	}
698 
699 	isc_buffer_init(&b, zonestr, sizeof(zonestr));
700 	result = dns_name_totext(&sdlz->common.origin, DNS_NAME_OMITFINALDOT,
701 				 &b);
702 	if (result != ISC_R_SUCCESS) {
703 		return result;
704 	}
705 	isc_buffer_putuint8(&b, 0);
706 
707 	sdlziter = isc_mem_get(sdlz->common.mctx, sizeof(sdlz_dbiterator_t));
708 
709 	sdlziter->common.methods = &dbiterator_methods;
710 	sdlziter->common.db = NULL;
711 	dns_db_attach(db, &sdlziter->common.db);
712 	sdlziter->common.relative_names = ((options & DNS_DB_RELATIVENAMES) !=
713 					   0);
714 	sdlziter->common.magic = DNS_DBITERATOR_MAGIC;
715 	ISC_LIST_INIT(sdlziter->nodelist);
716 	sdlziter->current = NULL;
717 	sdlziter->origin = NULL;
718 
719 	/* make sure strings are always lowercase */
720 	isc_ascii_strtolower(zonestr);
721 
722 	MAYBE_LOCK(sdlz->dlzimp);
723 	result = sdlz->dlzimp->methods->allnodes(
724 		zonestr, sdlz->dlzimp->driverarg, sdlz->dbdata, sdlziter);
725 	MAYBE_UNLOCK(sdlz->dlzimp);
726 	if (result != ISC_R_SUCCESS) {
727 		dns_dbiterator_t *iter = &sdlziter->common;
728 		dbiterator_destroy(&iter DNS__DB_FILELINE);
729 		return result;
730 	}
731 
732 	if (sdlziter->origin != NULL) {
733 		ISC_LIST_UNLINK(sdlziter->nodelist, sdlziter->origin, link);
734 		ISC_LIST_PREPEND(sdlziter->nodelist, sdlziter->origin, link);
735 	}
736 
737 	*iteratorp = (dns_dbiterator_t *)sdlziter;
738 
739 	return ISC_R_SUCCESS;
740 }
741 
742 static isc_result_t
743 findrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
744 	     dns_rdatatype_t type, dns_rdatatype_t covers, isc_stdtime_t now,
745 	     dns_rdataset_t *rdataset,
746 	     dns_rdataset_t *sigrdataset DNS__DB_FLARG) {
747 	REQUIRE(VALID_SDLZNODE(node));
748 	dns_rdatalist_t *list;
749 	dns_sdlznode_t *sdlznode = (dns_sdlznode_t *)node;
750 
751 	UNUSED(db);
752 	UNUSED(version);
753 	UNUSED(covers);
754 	UNUSED(now);
755 	UNUSED(sigrdataset);
756 
757 	if (type == dns_rdatatype_sig || type == dns_rdatatype_rrsig) {
758 		return ISC_R_NOTIMPLEMENTED;
759 	}
760 
761 	list = ISC_LIST_HEAD(sdlznode->lists);
762 	while (list != NULL) {
763 		if (list->type == type) {
764 			break;
765 		}
766 		list = ISC_LIST_NEXT(list, link);
767 	}
768 	if (list == NULL) {
769 		return ISC_R_NOTFOUND;
770 	}
771 
772 	list_tordataset(list, db, node, rdataset);
773 
774 	return ISC_R_SUCCESS;
775 }
776 
777 static isc_result_t
778 findext(dns_db_t *db, const dns_name_t *name, dns_dbversion_t *version,
779 	dns_rdatatype_t type, unsigned int options, isc_stdtime_t now,
780 	dns_dbnode_t **nodep, dns_name_t *foundname,
781 	dns_clientinfomethods_t *methods, dns_clientinfo_t *clientinfo,
782 	dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset DNS__DB_FLARG) {
783 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
784 	dns_dbnode_t *node = NULL;
785 	dns_fixedname_t fname;
786 	dns_rdataset_t xrdataset;
787 	dns_name_t *xname;
788 	unsigned int nlabels, olabels;
789 	isc_result_t result;
790 	unsigned int i;
791 
792 	REQUIRE(VALID_SDLZDB(sdlz));
793 	REQUIRE(nodep == NULL || *nodep == NULL);
794 	REQUIRE(version == NULL || version == (void *)&sdlz->dummy_version ||
795 		version == sdlz->future_version);
796 
797 	UNUSED(sdlz);
798 
799 	if (!dns_name_issubdomain(name, &db->origin)) {
800 		return DNS_R_NXDOMAIN;
801 	}
802 
803 	olabels = dns_name_countlabels(&db->origin);
804 	nlabels = dns_name_countlabels(name);
805 
806 	xname = dns_fixedname_initname(&fname);
807 
808 	if (rdataset == NULL) {
809 		dns_rdataset_init(&xrdataset);
810 		rdataset = &xrdataset;
811 	}
812 
813 	result = DNS_R_NXDOMAIN;
814 
815 	/*
816 	 * If we're not walking down searching for zone
817 	 * cuts, we can cut straight to the chase
818 	 */
819 	if ((options & DNS_DBFIND_NOZONECUT) != 0) {
820 		i = nlabels;
821 		goto search;
822 	}
823 
824 	for (i = olabels; i <= nlabels; i++) {
825 	search:
826 		/*
827 		 * Look up the next label.
828 		 */
829 		dns_name_getlabelsequence(name, nlabels - i, i, xname);
830 		result = getnodedata(db, xname, false, options, methods,
831 				     clientinfo, &node);
832 		if (result == ISC_R_NOTFOUND) {
833 			result = DNS_R_NXDOMAIN;
834 			continue;
835 		} else if (result != ISC_R_SUCCESS) {
836 			break;
837 		}
838 
839 		/*
840 		 * Look for a DNAME at the current label, unless this is
841 		 * the qname.
842 		 */
843 		if (i < nlabels) {
844 			result = findrdataset(
845 				db, node, version, dns_rdatatype_dname, 0, now,
846 				rdataset, sigrdataset DNS__DB_FLARG_PASS);
847 			if (result == ISC_R_SUCCESS) {
848 				result = DNS_R_DNAME;
849 				break;
850 			}
851 		}
852 
853 		/*
854 		 * Look for an NS at the current label, unless this is the
855 		 * origin, glue is ok, or there are known to be no zone cuts.
856 		 */
857 		if (i != olabels && (options & DNS_DBFIND_GLUEOK) == 0 &&
858 		    (options & DNS_DBFIND_NOZONECUT) == 0)
859 		{
860 			result = findrdataset(
861 				db, node, version, dns_rdatatype_ns, 0, now,
862 				rdataset, sigrdataset DNS__DB_FLARG_PASS);
863 
864 			if (result == ISC_R_SUCCESS && i == nlabels &&
865 			    type == dns_rdatatype_any)
866 			{
867 				result = DNS_R_ZONECUT;
868 				dns_rdataset_disassociate(rdataset);
869 				if (sigrdataset != NULL &&
870 				    dns_rdataset_isassociated(sigrdataset))
871 				{
872 					dns_rdataset_disassociate(sigrdataset);
873 				}
874 				break;
875 			} else if (result == ISC_R_SUCCESS) {
876 				result = DNS_R_DELEGATION;
877 				break;
878 			}
879 		}
880 
881 		/*
882 		 * If the current name is not the qname, add another label
883 		 * and try again.
884 		 */
885 		if (i < nlabels) {
886 			detachnode(db, &node DNS__DB_FLARG_PASS);
887 			node = NULL;
888 			continue;
889 		}
890 
891 		/*
892 		 * If we're looking for ANY, we're done.
893 		 */
894 		if (type == dns_rdatatype_any) {
895 			result = ISC_R_SUCCESS;
896 			break;
897 		}
898 
899 		/*
900 		 * Look for the qtype.
901 		 */
902 		result = findrdataset(db, node, version, type, 0, now, rdataset,
903 				      sigrdataset DNS__DB_FLARG_PASS);
904 		if (result == ISC_R_SUCCESS) {
905 			break;
906 		}
907 
908 		/*
909 		 * Look for a CNAME
910 		 */
911 		if (type != dns_rdatatype_cname) {
912 			result = findrdataset(
913 				db, node, version, dns_rdatatype_cname, 0, now,
914 				rdataset, sigrdataset DNS__DB_FLARG_PASS);
915 			if (result == ISC_R_SUCCESS) {
916 				result = DNS_R_CNAME;
917 				break;
918 			}
919 		}
920 
921 		result = DNS_R_NXRRSET;
922 		break;
923 	}
924 
925 	if (rdataset == &xrdataset && dns_rdataset_isassociated(rdataset)) {
926 		dns_rdataset_disassociate(rdataset);
927 	}
928 
929 	if (foundname != NULL) {
930 		dns_name_copy(xname, foundname);
931 	}
932 
933 	if (nodep != NULL) {
934 		*nodep = node;
935 	} else if (node != NULL) {
936 		detachnode(db, &node DNS__DB_FLARG_PASS);
937 	}
938 
939 	return result;
940 }
941 
942 static isc_result_t
943 find(dns_db_t *db, const dns_name_t *name, dns_dbversion_t *version,
944      dns_rdatatype_t type, unsigned int options, isc_stdtime_t now,
945      dns_dbnode_t **nodep, dns_name_t *foundname, dns_rdataset_t *rdataset,
946      dns_rdataset_t *sigrdataset DNS__DB_FLARG) {
947 	return findext(db, name, version, type, options, now, nodep, foundname,
948 		       NULL, NULL, rdataset, sigrdataset DNS__DB_FLARG_PASS);
949 }
950 
951 static isc_result_t
952 allrdatasets(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
953 	     unsigned int options, isc_stdtime_t now,
954 	     dns_rdatasetiter_t **iteratorp DNS__DB_FLARG) {
955 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
956 	sdlz_rdatasetiter_t *iterator;
957 
958 	REQUIRE(VALID_SDLZDB(sdlz));
959 
960 	REQUIRE(version == NULL || version == (void *)&sdlz->dummy_version ||
961 		version == sdlz->future_version);
962 
963 	UNUSED(version);
964 	UNUSED(now);
965 
966 	iterator = isc_mem_get(db->mctx, sizeof(sdlz_rdatasetiter_t));
967 
968 	iterator->common.magic = DNS_RDATASETITER_MAGIC;
969 	iterator->common.methods = &rdatasetiter_methods;
970 	iterator->common.db = db;
971 	iterator->common.node = NULL;
972 	attachnode(db, node, &iterator->common.node DNS__DB_FLARG_PASS);
973 	iterator->common.version = version;
974 	iterator->common.options = options;
975 	iterator->common.now = now;
976 
977 	*iteratorp = (dns_rdatasetiter_t *)iterator;
978 
979 	return ISC_R_SUCCESS;
980 }
981 
982 static isc_result_t
983 modrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
984 	    dns_rdataset_t *rdataset, unsigned int options,
985 	    dns_sdlzmodrdataset_t mod_function) {
986 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
987 	dns_master_style_t *style = NULL;
988 	isc_result_t result;
989 	isc_buffer_t *buffer = NULL;
990 	isc_mem_t *mctx;
991 	dns_sdlznode_t *sdlznode;
992 	char *rdatastr = NULL;
993 	char name[DNS_NAME_MAXTEXT + 1];
994 
995 	REQUIRE(VALID_SDLZDB(sdlz));
996 
997 	if (mod_function == NULL) {
998 		return ISC_R_NOTIMPLEMENTED;
999 	}
1000 
1001 	sdlznode = (dns_sdlznode_t *)node;
1002 
1003 	UNUSED(options);
1004 
1005 	dns_name_format(sdlznode->name, name, sizeof(name));
1006 
1007 	mctx = sdlz->common.mctx;
1008 
1009 	isc_buffer_allocate(mctx, &buffer, 1024);
1010 
1011 	result = dns_master_stylecreate(&style, 0, 0, 0, 0, 0, 0, 1, 0xffffffff,
1012 					mctx);
1013 	if (result != ISC_R_SUCCESS) {
1014 		goto cleanup;
1015 	}
1016 
1017 	result = dns_master_rdatasettotext(sdlznode->name, rdataset, style,
1018 					   NULL, buffer);
1019 	if (result != ISC_R_SUCCESS) {
1020 		goto cleanup;
1021 	}
1022 
1023 	if (isc_buffer_usedlength(buffer) < 1) {
1024 		result = ISC_R_BADADDRESSFORM;
1025 		goto cleanup;
1026 	}
1027 
1028 	rdatastr = isc_buffer_base(buffer);
1029 	if (rdatastr == NULL) {
1030 		result = ISC_R_NOMEMORY;
1031 		goto cleanup;
1032 	}
1033 	rdatastr[isc_buffer_usedlength(buffer) - 1] = 0;
1034 
1035 	MAYBE_LOCK(sdlz->dlzimp);
1036 	result = mod_function(name, rdatastr, sdlz->dlzimp->driverarg,
1037 			      sdlz->dbdata, version);
1038 	MAYBE_UNLOCK(sdlz->dlzimp);
1039 
1040 cleanup:
1041 	isc_buffer_free(&buffer);
1042 	if (style != NULL) {
1043 		dns_master_styledestroy(&style, mctx);
1044 	}
1045 
1046 	return result;
1047 }
1048 
1049 static isc_result_t
1050 addrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
1051 	    isc_stdtime_t now, dns_rdataset_t *rdataset, unsigned int options,
1052 	    dns_rdataset_t *addedrdataset DNS__DB_FLARG) {
1053 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
1054 	isc_result_t result;
1055 
1056 	UNUSED(now);
1057 	UNUSED(addedrdataset);
1058 	REQUIRE(VALID_SDLZDB(sdlz));
1059 
1060 	if (sdlz->dlzimp->methods->addrdataset == NULL) {
1061 		return ISC_R_NOTIMPLEMENTED;
1062 	}
1063 
1064 	result = modrdataset(db, node, version, rdataset, options,
1065 			     sdlz->dlzimp->methods->addrdataset);
1066 	return result;
1067 }
1068 
1069 static isc_result_t
1070 subtractrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
1071 		 dns_rdataset_t *rdataset, unsigned int options,
1072 		 dns_rdataset_t *newrdataset DNS__DB_FLARG) {
1073 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
1074 	isc_result_t result;
1075 
1076 	UNUSED(newrdataset);
1077 	REQUIRE(VALID_SDLZDB(sdlz));
1078 
1079 	if (sdlz->dlzimp->methods->subtractrdataset == NULL) {
1080 		return ISC_R_NOTIMPLEMENTED;
1081 	}
1082 
1083 	result = modrdataset(db, node, version, rdataset, options,
1084 			     sdlz->dlzimp->methods->subtractrdataset);
1085 	return result;
1086 }
1087 
1088 static isc_result_t
1089 deleterdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version,
1090 	       dns_rdatatype_t type, dns_rdatatype_t covers DNS__DB_FLARG) {
1091 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
1092 	char name[DNS_NAME_MAXTEXT + 1];
1093 	char b_type[DNS_RDATATYPE_FORMATSIZE];
1094 	dns_sdlznode_t *sdlznode;
1095 	isc_result_t result;
1096 
1097 	UNUSED(covers);
1098 
1099 	REQUIRE(VALID_SDLZDB(sdlz));
1100 
1101 	if (sdlz->dlzimp->methods->delrdataset == NULL) {
1102 		return ISC_R_NOTIMPLEMENTED;
1103 	}
1104 
1105 	sdlznode = (dns_sdlznode_t *)node;
1106 	dns_name_format(sdlznode->name, name, sizeof(name));
1107 	dns_rdatatype_format(type, b_type, sizeof(b_type));
1108 
1109 	MAYBE_LOCK(sdlz->dlzimp);
1110 	result = sdlz->dlzimp->methods->delrdataset(
1111 		name, b_type, sdlz->dlzimp->driverarg, sdlz->dbdata, version);
1112 	MAYBE_UNLOCK(sdlz->dlzimp);
1113 
1114 	return result;
1115 }
1116 
1117 static bool
1118 issecure(dns_db_t *db) {
1119 	UNUSED(db);
1120 
1121 	return false;
1122 }
1123 
1124 static unsigned int
1125 nodecount(dns_db_t *db, dns_dbtree_t tree) {
1126 	UNUSED(db);
1127 	UNUSED(tree);
1128 
1129 	return 0;
1130 }
1131 
1132 static void
1133 setloop(dns_db_t *db, isc_loop_t *loop) {
1134 	UNUSED(db);
1135 	UNUSED(loop);
1136 }
1137 
1138 /*
1139  * getoriginnode() is used by the update code to find the
1140  * dns_rdatatype_dnskey record for a zone
1141  */
1142 static isc_result_t
1143 getoriginnode(dns_db_t *db, dns_dbnode_t **nodep DNS__DB_FLARG) {
1144 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)db;
1145 	isc_result_t result;
1146 
1147 	REQUIRE(VALID_SDLZDB(sdlz));
1148 	if (sdlz->dlzimp->methods->newversion == NULL) {
1149 		return ISC_R_NOTIMPLEMENTED;
1150 	}
1151 
1152 	result = getnodedata(db, &sdlz->common.origin, false, 0, NULL, NULL,
1153 			     nodep);
1154 	if (result != ISC_R_SUCCESS) {
1155 		sdlz_log(ISC_LOG_ERROR, "sdlz getoriginnode failed: %s",
1156 			 isc_result_totext(result));
1157 	}
1158 	return result;
1159 }
1160 
1161 static dns_dbmethods_t sdlzdb_methods = {
1162 	.destroy = destroy,
1163 	.currentversion = currentversion,
1164 	.newversion = newversion,
1165 	.attachversion = attachversion,
1166 	.closeversion = closeversion,
1167 	.findnode = findnode,
1168 	.find = find,
1169 	.attachnode = attachnode,
1170 	.detachnode = detachnode,
1171 	.createiterator = createiterator,
1172 	.findrdataset = findrdataset,
1173 	.allrdatasets = allrdatasets,
1174 	.addrdataset = addrdataset,
1175 	.subtractrdataset = subtractrdataset,
1176 	.deleterdataset = deleterdataset,
1177 	.issecure = issecure,
1178 	.nodecount = nodecount,
1179 	.setloop = setloop,
1180 	.getoriginnode = getoriginnode,
1181 	.findnodeext = findnodeext,
1182 	.findext = findext,
1183 };
1184 
1185 /*
1186  * Database Iterator Methods.  These methods were "borrowed" from the SDB
1187  * driver interface.  See the SDB driver interface documentation for more info.
1188  */
1189 
1190 static void
1191 dbiterator_destroy(dns_dbiterator_t **iteratorp DNS__DB_FLARG) {
1192 	sdlz_dbiterator_t *sdlziter = (sdlz_dbiterator_t *)(*iteratorp);
1193 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)sdlziter->common.db;
1194 
1195 	while (!ISC_LIST_EMPTY(sdlziter->nodelist)) {
1196 		dns_sdlznode_t *node;
1197 		node = ISC_LIST_HEAD(sdlziter->nodelist);
1198 		ISC_LIST_UNLINK(sdlziter->nodelist, node, link);
1199 		isc_refcount_decrementz(&node->references);
1200 		destroynode(node);
1201 	}
1202 
1203 	dns_db_detach(&sdlziter->common.db);
1204 	isc_mem_put(sdlz->common.mctx, sdlziter, sizeof(sdlz_dbiterator_t));
1205 
1206 	*iteratorp = NULL;
1207 }
1208 
1209 static isc_result_t
1210 dbiterator_first(dns_dbiterator_t *iterator DNS__DB_FLARG) {
1211 	sdlz_dbiterator_t *sdlziter = (sdlz_dbiterator_t *)iterator;
1212 
1213 	sdlziter->current = ISC_LIST_HEAD(sdlziter->nodelist);
1214 	if (sdlziter->current == NULL) {
1215 		return ISC_R_NOMORE;
1216 	} else {
1217 		return ISC_R_SUCCESS;
1218 	}
1219 }
1220 
1221 static isc_result_t
1222 dbiterator_last(dns_dbiterator_t *iterator DNS__DB_FLARG) {
1223 	sdlz_dbiterator_t *sdlziter = (sdlz_dbiterator_t *)iterator;
1224 
1225 	sdlziter->current = ISC_LIST_TAIL(sdlziter->nodelist);
1226 	if (sdlziter->current == NULL) {
1227 		return ISC_R_NOMORE;
1228 	} else {
1229 		return ISC_R_SUCCESS;
1230 	}
1231 }
1232 
1233 static isc_result_t
1234 dbiterator_seek(dns_dbiterator_t *iterator,
1235 		const dns_name_t *name DNS__DB_FLARG) {
1236 	sdlz_dbiterator_t *sdlziter = (sdlz_dbiterator_t *)iterator;
1237 
1238 	sdlziter->current = ISC_LIST_HEAD(sdlziter->nodelist);
1239 	while (sdlziter->current != NULL) {
1240 		if (dns_name_equal(sdlziter->current->name, name)) {
1241 			return ISC_R_SUCCESS;
1242 		}
1243 		sdlziter->current = ISC_LIST_NEXT(sdlziter->current, link);
1244 	}
1245 	return ISC_R_NOTFOUND;
1246 }
1247 
1248 static isc_result_t
1249 dbiterator_prev(dns_dbiterator_t *iterator DNS__DB_FLARG) {
1250 	sdlz_dbiterator_t *sdlziter = (sdlz_dbiterator_t *)iterator;
1251 
1252 	sdlziter->current = ISC_LIST_PREV(sdlziter->current, link);
1253 	if (sdlziter->current == NULL) {
1254 		return ISC_R_NOMORE;
1255 	} else {
1256 		return ISC_R_SUCCESS;
1257 	}
1258 }
1259 
1260 static isc_result_t
1261 dbiterator_next(dns_dbiterator_t *iterator DNS__DB_FLARG) {
1262 	sdlz_dbiterator_t *sdlziter = (sdlz_dbiterator_t *)iterator;
1263 
1264 	sdlziter->current = ISC_LIST_NEXT(sdlziter->current, link);
1265 	if (sdlziter->current == NULL) {
1266 		return ISC_R_NOMORE;
1267 	} else {
1268 		return ISC_R_SUCCESS;
1269 	}
1270 }
1271 
1272 static isc_result_t
1273 dbiterator_current(dns_dbiterator_t *iterator, dns_dbnode_t **nodep,
1274 		   dns_name_t *name DNS__DB_FLARG) {
1275 	sdlz_dbiterator_t *sdlziter = (sdlz_dbiterator_t *)iterator;
1276 
1277 	attachnode(iterator->db, sdlziter->current, nodep DNS__DB_FLARG_PASS);
1278 	if (name != NULL) {
1279 		dns_name_copy(sdlziter->current->name, name);
1280 		return ISC_R_SUCCESS;
1281 	}
1282 	return ISC_R_SUCCESS;
1283 }
1284 
1285 static isc_result_t
1286 dbiterator_pause(dns_dbiterator_t *iterator) {
1287 	UNUSED(iterator);
1288 	return ISC_R_SUCCESS;
1289 }
1290 
1291 static isc_result_t
1292 dbiterator_origin(dns_dbiterator_t *iterator, dns_name_t *name) {
1293 	UNUSED(iterator);
1294 	dns_name_copy(dns_rootname, name);
1295 	return ISC_R_SUCCESS;
1296 }
1297 
1298 /*
1299  * Rdataset Methods. These methods were "borrowed" from the SDB driver
1300  * interface.  See the SDB driver interface documentation for more info.
1301  */
1302 
1303 static void
1304 disassociate(dns_rdataset_t *rdataset DNS__DB_FLARG) {
1305 	dns_dbnode_t *node = rdataset->rdlist.node;
1306 	dns_sdlznode_t *sdlznode = (dns_sdlznode_t *)node;
1307 	dns_db_t *db = (dns_db_t *)sdlznode->sdlz;
1308 
1309 	detachnode(db, &node DNS__DB_FLARG_PASS);
1310 	dns_rdatalist_disassociate(rdataset DNS__DB_FLARG_PASS);
1311 }
1312 
1313 static void
1314 rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target DNS__DB_FLARG) {
1315 	dns_dbnode_t *node = source->rdlist.node;
1316 	dns_sdlznode_t *sdlznode = (dns_sdlznode_t *)node;
1317 	dns_db_t *db = (dns_db_t *)sdlznode->sdlz;
1318 
1319 	dns_rdatalist_clone(source, target DNS__DB_FLARG_PASS);
1320 	attachnode(db, node, &target->rdlist.node DNS__DB_FLARG_PASS);
1321 }
1322 
1323 static dns_rdatasetmethods_t rdataset_methods = {
1324 	.disassociate = disassociate,
1325 	.first = dns_rdatalist_first,
1326 	.next = dns_rdatalist_next,
1327 	.current = dns_rdatalist_current,
1328 	.clone = rdataset_clone,
1329 	.count = dns_rdatalist_count,
1330 	.addnoqname = dns_rdatalist_addnoqname,
1331 	.getnoqname = dns_rdatalist_getnoqname,
1332 };
1333 
1334 static void
1335 list_tordataset(dns_rdatalist_t *rdatalist, dns_db_t *db, dns_dbnode_t *node,
1336 		dns_rdataset_t *rdataset) {
1337 	/*
1338 	 * The sdlz rdataset is an rdatalist, but additionally holds
1339 	 * a database node reference.
1340 	 */
1341 
1342 	dns_rdatalist_tordataset(rdatalist, rdataset);
1343 	rdataset->methods = &rdataset_methods;
1344 	dns_db_attachnode(db, node, &rdataset->rdlist.node);
1345 }
1346 
1347 /*
1348  * SDLZ core methods. This is the core of the new DLZ functionality.
1349  */
1350 
1351 /*%
1352  * Build a 'bind' database driver structure to be returned by
1353  * either the find zone or the allow zone transfer method.
1354  * This method is only available in this source file, it is
1355  * not made available anywhere else.
1356  */
1357 
1358 static isc_result_t
1359 dns_sdlzcreateDBP(isc_mem_t *mctx, void *driverarg, void *dbdata,
1360 		  const dns_name_t *name, dns_rdataclass_t rdclass,
1361 		  dns_db_t **dbp) {
1362 	dns_sdlz_db_t *sdlzdb;
1363 	dns_sdlzimplementation_t *imp;
1364 
1365 	/* check that things are as we expect */
1366 	REQUIRE(dbp != NULL && *dbp == NULL);
1367 	REQUIRE(name != NULL);
1368 
1369 	imp = (dns_sdlzimplementation_t *)driverarg;
1370 
1371 	/* allocate and zero memory for driver structure */
1372 	sdlzdb = isc_mem_get(mctx, sizeof(*sdlzdb));
1373 
1374 	*sdlzdb = (dns_sdlz_db_t) {
1375 		.dlzimp = imp,
1376 		.common = { .methods = &sdlzdb_methods,
1377 			.rdclass = rdclass, },
1378 			.dbdata = dbdata,
1379 	};
1380 
1381 	/* initialize and set origin */
1382 	dns_name_init(&sdlzdb->common.origin, NULL);
1383 	dns_name_dupwithoffsets(name, mctx, &sdlzdb->common.origin);
1384 
1385 	isc_refcount_init(&sdlzdb->common.references, 1);
1386 
1387 	/* attach to the memory context */
1388 	isc_mem_attach(mctx, &sdlzdb->common.mctx);
1389 
1390 	/* mark structure as valid */
1391 	sdlzdb->common.magic = DNS_DB_MAGIC;
1392 	sdlzdb->common.impmagic = SDLZDB_MAGIC;
1393 	*dbp = (dns_db_t *)sdlzdb;
1394 
1395 	return ISC_R_SUCCESS;
1396 }
1397 
1398 static isc_result_t
1399 dns_sdlzallowzonexfr(void *driverarg, void *dbdata, isc_mem_t *mctx,
1400 		     dns_rdataclass_t rdclass, const dns_name_t *name,
1401 		     const isc_sockaddr_t *clientaddr, dns_db_t **dbp) {
1402 	isc_buffer_t b;
1403 	isc_buffer_t b2;
1404 	char namestr[DNS_NAME_MAXTEXT + 1];
1405 	char clientstr[(sizeof "xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255."
1406 			       "255") +
1407 		       1];
1408 	isc_netaddr_t netaddr;
1409 	isc_result_t result;
1410 	dns_sdlzimplementation_t *imp;
1411 
1412 	/*
1413 	 * Perform checks to make sure data is as we expect it to be.
1414 	 */
1415 	REQUIRE(driverarg != NULL);
1416 	REQUIRE(name != NULL);
1417 	REQUIRE(clientaddr != NULL);
1418 	REQUIRE(dbp != NULL && *dbp == NULL);
1419 
1420 	imp = (dns_sdlzimplementation_t *)driverarg;
1421 
1422 	/* Convert DNS name to ascii text */
1423 	isc_buffer_init(&b, namestr, sizeof(namestr));
1424 	result = dns_name_totext(name, DNS_NAME_OMITFINALDOT, &b);
1425 	if (result != ISC_R_SUCCESS) {
1426 		return result;
1427 	}
1428 	isc_buffer_putuint8(&b, 0);
1429 
1430 	/* convert client address to ascii text */
1431 	isc_buffer_init(&b2, clientstr, sizeof(clientstr));
1432 	isc_netaddr_fromsockaddr(&netaddr, clientaddr);
1433 	result = isc_netaddr_totext(&netaddr, &b2);
1434 	if (result != ISC_R_SUCCESS) {
1435 		return result;
1436 	}
1437 	isc_buffer_putuint8(&b2, 0);
1438 
1439 	/* make sure strings are always lowercase */
1440 	isc_ascii_strtolower(namestr);
1441 	isc_ascii_strtolower(clientstr);
1442 
1443 	/* Call SDLZ driver's find zone method */
1444 	if (imp->methods->allowzonexfr != NULL) {
1445 		isc_result_t rresult = ISC_R_SUCCESS;
1446 
1447 		MAYBE_LOCK(imp);
1448 		result = imp->methods->allowzonexfr(imp->driverarg, dbdata,
1449 						    namestr, clientstr);
1450 		MAYBE_UNLOCK(imp);
1451 		/*
1452 		 * if zone is supported and transfers are (or might be)
1453 		 * allowed, build a 'bind' database driver
1454 		 */
1455 		if (result == ISC_R_SUCCESS || result == ISC_R_DEFAULT) {
1456 			rresult = dns_sdlzcreateDBP(mctx, driverarg, dbdata,
1457 						    name, rdclass, dbp);
1458 		}
1459 		if (rresult != ISC_R_SUCCESS) {
1460 			result = rresult;
1461 		}
1462 		return result;
1463 	}
1464 
1465 	return ISC_R_NOTIMPLEMENTED;
1466 }
1467 
1468 static isc_result_t
1469 dns_sdlzcreate(isc_mem_t *mctx, const char *dlzname, unsigned int argc,
1470 	       char *argv[], void *driverarg, void **dbdata) {
1471 	dns_sdlzimplementation_t *imp;
1472 	isc_result_t result = ISC_R_NOTFOUND;
1473 
1474 	/* Write debugging message to log */
1475 	sdlz_log(ISC_LOG_DEBUG(2), "Loading SDLZ driver.");
1476 
1477 	/*
1478 	 * Performs checks to make sure data is as we expect it to be.
1479 	 */
1480 	REQUIRE(driverarg != NULL);
1481 	REQUIRE(dlzname != NULL);
1482 	REQUIRE(dbdata != NULL);
1483 	UNUSED(mctx);
1484 
1485 	imp = driverarg;
1486 
1487 	/* If the create method exists, call it. */
1488 	if (imp->methods->create != NULL) {
1489 		MAYBE_LOCK(imp);
1490 		result = imp->methods->create(dlzname, argc, argv,
1491 					      imp->driverarg, dbdata);
1492 		MAYBE_UNLOCK(imp);
1493 	}
1494 
1495 	/* Write debugging message to log */
1496 	if (result == ISC_R_SUCCESS) {
1497 		sdlz_log(ISC_LOG_DEBUG(2), "SDLZ driver loaded successfully.");
1498 	} else {
1499 		sdlz_log(ISC_LOG_ERROR, "SDLZ driver failed to load.");
1500 	}
1501 
1502 	return result;
1503 }
1504 
1505 static void
1506 dns_sdlzdestroy(void *driverdata, void **dbdata) {
1507 	dns_sdlzimplementation_t *imp;
1508 
1509 	/* Write debugging message to log */
1510 	sdlz_log(ISC_LOG_DEBUG(2), "Unloading SDLZ driver.");
1511 
1512 	imp = driverdata;
1513 
1514 	/* If the destroy method exists, call it. */
1515 	if (imp->methods->destroy != NULL) {
1516 		MAYBE_LOCK(imp);
1517 		imp->methods->destroy(imp->driverarg, dbdata);
1518 		MAYBE_UNLOCK(imp);
1519 	}
1520 }
1521 
1522 static isc_result_t
1523 dns_sdlzfindzone(void *driverarg, void *dbdata, isc_mem_t *mctx,
1524 		 dns_rdataclass_t rdclass, const dns_name_t *name,
1525 		 dns_clientinfomethods_t *methods, dns_clientinfo_t *clientinfo,
1526 		 dns_db_t **dbp) {
1527 	isc_buffer_t b;
1528 	char namestr[DNS_NAME_MAXTEXT + 1];
1529 	isc_result_t result;
1530 	dns_sdlzimplementation_t *imp;
1531 
1532 	/*
1533 	 * Perform checks to make sure data is as we expect it to be.
1534 	 */
1535 	REQUIRE(driverarg != NULL);
1536 	REQUIRE(name != NULL);
1537 	REQUIRE(dbp != NULL && *dbp == NULL);
1538 
1539 	imp = (dns_sdlzimplementation_t *)driverarg;
1540 
1541 	/* Convert DNS name to ascii text */
1542 	isc_buffer_init(&b, namestr, sizeof(namestr));
1543 	result = dns_name_totext(name, DNS_NAME_OMITFINALDOT, &b);
1544 	if (result != ISC_R_SUCCESS) {
1545 		return result;
1546 	}
1547 	isc_buffer_putuint8(&b, 0);
1548 
1549 	/* make sure strings are always lowercase */
1550 	isc_ascii_strtolower(namestr);
1551 
1552 	/* Call SDLZ driver's find zone method */
1553 	MAYBE_LOCK(imp);
1554 	result = imp->methods->findzone(imp->driverarg, dbdata, namestr,
1555 					methods, clientinfo);
1556 	MAYBE_UNLOCK(imp);
1557 
1558 	/*
1559 	 * if zone is supported build a 'bind' database driver
1560 	 * structure to return
1561 	 */
1562 	if (result == ISC_R_SUCCESS) {
1563 		result = dns_sdlzcreateDBP(mctx, driverarg, dbdata, name,
1564 					   rdclass, dbp);
1565 	}
1566 
1567 	return result;
1568 }
1569 
1570 static isc_result_t
1571 dns_sdlzconfigure(void *driverarg, void *dbdata, dns_view_t *view,
1572 		  dns_dlzdb_t *dlzdb) {
1573 	isc_result_t result;
1574 	dns_sdlzimplementation_t *imp;
1575 
1576 	REQUIRE(driverarg != NULL);
1577 
1578 	imp = (dns_sdlzimplementation_t *)driverarg;
1579 
1580 	/* Call SDLZ driver's configure method */
1581 	if (imp->methods->configure != NULL) {
1582 		MAYBE_LOCK(imp);
1583 		result = imp->methods->configure(view, dlzdb, imp->driverarg,
1584 						 dbdata);
1585 		MAYBE_UNLOCK(imp);
1586 	} else {
1587 		result = ISC_R_SUCCESS;
1588 	}
1589 
1590 	return result;
1591 }
1592 
1593 static bool
1594 dns_sdlzssumatch(const dns_name_t *signer, const dns_name_t *name,
1595 		 const isc_netaddr_t *tcpaddr, dns_rdatatype_t type,
1596 		 const dst_key_t *key, void *driverarg, void *dbdata) {
1597 	dns_sdlzimplementation_t *imp;
1598 	char b_signer[DNS_NAME_FORMATSIZE];
1599 	char b_name[DNS_NAME_FORMATSIZE];
1600 	char b_addr[ISC_NETADDR_FORMATSIZE];
1601 	char b_type[DNS_RDATATYPE_FORMATSIZE];
1602 	char b_key[DST_KEY_FORMATSIZE];
1603 	isc_buffer_t *tkey_token = NULL;
1604 	isc_region_t token_region = { NULL, 0 };
1605 	uint32_t token_len = 0;
1606 	bool ret;
1607 
1608 	REQUIRE(driverarg != NULL);
1609 
1610 	imp = (dns_sdlzimplementation_t *)driverarg;
1611 	if (imp->methods->ssumatch == NULL) {
1612 		return false;
1613 	}
1614 
1615 	/*
1616 	 * Format the request elements. sdlz operates on strings, not
1617 	 * structures
1618 	 */
1619 	if (signer != NULL) {
1620 		dns_name_format(signer, b_signer, sizeof(b_signer));
1621 	} else {
1622 		b_signer[0] = 0;
1623 	}
1624 
1625 	dns_name_format(name, b_name, sizeof(b_name));
1626 
1627 	if (tcpaddr != NULL) {
1628 		isc_netaddr_format(tcpaddr, b_addr, sizeof(b_addr));
1629 	} else {
1630 		b_addr[0] = 0;
1631 	}
1632 
1633 	dns_rdatatype_format(type, b_type, sizeof(b_type));
1634 
1635 	if (key != NULL) {
1636 		dst_key_format(key, b_key, sizeof(b_key));
1637 		tkey_token = dst_key_tkeytoken(key);
1638 	} else {
1639 		b_key[0] = 0;
1640 	}
1641 
1642 	if (tkey_token != NULL) {
1643 		isc_buffer_region(tkey_token, &token_region);
1644 		token_len = token_region.length;
1645 	}
1646 
1647 	MAYBE_LOCK(imp);
1648 	ret = imp->methods->ssumatch(b_signer, b_name, b_addr, b_type, b_key,
1649 				     token_len,
1650 				     token_len != 0 ? token_region.base : NULL,
1651 				     imp->driverarg, dbdata);
1652 	MAYBE_UNLOCK(imp);
1653 	return ret;
1654 }
1655 
1656 static dns_dlzmethods_t sdlzmethods = { dns_sdlzcreate,	   dns_sdlzdestroy,
1657 					dns_sdlzfindzone,  dns_sdlzallowzonexfr,
1658 					dns_sdlzconfigure, dns_sdlzssumatch };
1659 
1660 /*
1661  * Public functions.
1662  */
1663 
1664 isc_result_t
1665 dns_sdlz_putrr(dns_sdlzlookup_t *lookup, const char *type, dns_ttl_t ttl,
1666 	       const char *data) {
1667 	dns_rdatalist_t *rdatalist;
1668 	dns_rdata_t *rdata;
1669 	dns_rdatatype_t typeval;
1670 	isc_consttextregion_t r;
1671 	isc_buffer_t b;
1672 	isc_buffer_t *rdatabuf = NULL;
1673 	isc_lex_t *lex;
1674 	isc_result_t result;
1675 	unsigned int size;
1676 	isc_mem_t *mctx;
1677 	const dns_name_t *origin;
1678 
1679 	REQUIRE(VALID_SDLZLOOKUP(lookup));
1680 	REQUIRE(type != NULL);
1681 	REQUIRE(data != NULL);
1682 
1683 	mctx = lookup->sdlz->common.mctx;
1684 
1685 	r.base = type;
1686 	r.length = strlen(type);
1687 	result = dns_rdatatype_fromtext(&typeval, (void *)&r);
1688 	if (result != ISC_R_SUCCESS) {
1689 		return result;
1690 	}
1691 
1692 	rdatalist = ISC_LIST_HEAD(lookup->lists);
1693 	while (rdatalist != NULL) {
1694 		if (rdatalist->type == typeval) {
1695 			break;
1696 		}
1697 		rdatalist = ISC_LIST_NEXT(rdatalist, link);
1698 	}
1699 
1700 	if (rdatalist == NULL) {
1701 		rdatalist = isc_mem_get(mctx, sizeof(dns_rdatalist_t));
1702 		dns_rdatalist_init(rdatalist);
1703 		rdatalist->rdclass = lookup->sdlz->common.rdclass;
1704 		rdatalist->type = typeval;
1705 		rdatalist->ttl = ttl;
1706 		ISC_LIST_APPEND(lookup->lists, rdatalist, link);
1707 	} else if (rdatalist->ttl > ttl) {
1708 		/*
1709 		 * BIND9 doesn't enforce all RRs in an RRset
1710 		 * having the same TTL, as per RFC 2136,
1711 		 * section 7.12. If a DLZ backend has
1712 		 * different TTLs, then the best
1713 		 * we can do is return the lowest.
1714 		 */
1715 		rdatalist->ttl = ttl;
1716 	}
1717 
1718 	rdata = isc_mem_get(mctx, sizeof(dns_rdata_t));
1719 	dns_rdata_init(rdata);
1720 
1721 	if ((lookup->sdlz->dlzimp->flags & DNS_SDLZFLAG_RELATIVERDATA) != 0) {
1722 		origin = &lookup->sdlz->common.origin;
1723 	} else {
1724 		origin = dns_rootname;
1725 	}
1726 
1727 	lex = NULL;
1728 	isc_lex_create(mctx, 64, &lex);
1729 
1730 	size = initial_size(data);
1731 	do {
1732 		isc_buffer_constinit(&b, data, strlen(data));
1733 		isc_buffer_add(&b, strlen(data));
1734 
1735 		result = isc_lex_openbuffer(lex, &b);
1736 		if (result != ISC_R_SUCCESS) {
1737 			goto failure;
1738 		}
1739 
1740 		rdatabuf = NULL;
1741 		isc_buffer_allocate(mctx, &rdatabuf, size);
1742 
1743 		result = dns_rdata_fromtext(rdata, rdatalist->rdclass,
1744 					    rdatalist->type, lex, origin, false,
1745 					    mctx, rdatabuf, &lookup->callbacks);
1746 		if (result != ISC_R_SUCCESS) {
1747 			isc_buffer_free(&rdatabuf);
1748 		}
1749 		if (size >= 65535) {
1750 			break;
1751 		}
1752 		size *= 2;
1753 		if (size >= 65535) {
1754 			size = 65535;
1755 		}
1756 	} while (result == ISC_R_NOSPACE);
1757 
1758 	if (result != ISC_R_SUCCESS) {
1759 		result = DNS_R_SERVFAIL;
1760 		goto failure;
1761 	}
1762 
1763 	ISC_LIST_APPEND(rdatalist->rdata, rdata, link);
1764 	ISC_LIST_APPEND(lookup->buffers, rdatabuf, link);
1765 
1766 	if (lex != NULL) {
1767 		isc_lex_destroy(&lex);
1768 	}
1769 
1770 	return ISC_R_SUCCESS;
1771 
1772 failure:
1773 	if (rdatabuf != NULL) {
1774 		isc_buffer_free(&rdatabuf);
1775 	}
1776 	if (lex != NULL) {
1777 		isc_lex_destroy(&lex);
1778 	}
1779 	isc_mem_put(mctx, rdata, sizeof(dns_rdata_t));
1780 
1781 	return result;
1782 }
1783 
1784 isc_result_t
1785 dns_sdlz_putnamedrr(dns_sdlzallnodes_t *allnodes, const char *name,
1786 		    const char *type, dns_ttl_t ttl, const char *data) {
1787 	dns_name_t *newname;
1788 	const dns_name_t *origin;
1789 	dns_fixedname_t fnewname;
1790 	dns_sdlz_db_t *sdlz = (dns_sdlz_db_t *)allnodes->common.db;
1791 	dns_sdlznode_t *sdlznode;
1792 	isc_mem_t *mctx = sdlz->common.mctx;
1793 	isc_buffer_t b;
1794 	isc_result_t result;
1795 
1796 	newname = dns_fixedname_initname(&fnewname);
1797 
1798 	if ((sdlz->dlzimp->flags & DNS_SDLZFLAG_RELATIVERDATA) != 0) {
1799 		origin = &sdlz->common.origin;
1800 	} else {
1801 		origin = dns_rootname;
1802 	}
1803 	isc_buffer_constinit(&b, name, strlen(name));
1804 	isc_buffer_add(&b, strlen(name));
1805 
1806 	result = dns_name_fromtext(newname, &b, origin, 0, NULL);
1807 	if (result != ISC_R_SUCCESS) {
1808 		return result;
1809 	}
1810 
1811 	if (allnodes->common.relative_names) {
1812 		/* All names are relative to the root */
1813 		unsigned int nlabels = dns_name_countlabels(newname);
1814 		dns_name_getlabelsequence(newname, 0, nlabels - 1, newname);
1815 	}
1816 
1817 	sdlznode = ISC_LIST_HEAD(allnodes->nodelist);
1818 	if (sdlznode == NULL || !dns_name_equal(sdlznode->name, newname)) {
1819 		sdlznode = NULL;
1820 		result = createnode(sdlz, &sdlznode);
1821 		if (result != ISC_R_SUCCESS) {
1822 			return result;
1823 		}
1824 		sdlznode->name = isc_mem_get(mctx, sizeof(dns_name_t));
1825 		dns_name_init(sdlznode->name, NULL);
1826 		dns_name_dup(newname, mctx, sdlznode->name);
1827 		ISC_LIST_PREPEND(allnodes->nodelist, sdlznode, link);
1828 		if (allnodes->origin == NULL &&
1829 		    dns_name_equal(newname, &sdlz->common.origin))
1830 		{
1831 			allnodes->origin = sdlznode;
1832 		}
1833 	}
1834 	return dns_sdlz_putrr(sdlznode, type, ttl, data);
1835 }
1836 
1837 isc_result_t
1838 dns_sdlz_putsoa(dns_sdlzlookup_t *lookup, const char *mname, const char *rname,
1839 		uint32_t serial) {
1840 	char str[2 * DNS_NAME_MAXTEXT + 5 * (sizeof("2147483647")) + 7];
1841 	int n;
1842 
1843 	REQUIRE(mname != NULL);
1844 	REQUIRE(rname != NULL);
1845 
1846 	n = snprintf(str, sizeof str, "%s %s %u %u %u %u %u", mname, rname,
1847 		     serial, SDLZ_DEFAULT_REFRESH, SDLZ_DEFAULT_RETRY,
1848 		     SDLZ_DEFAULT_EXPIRE, SDLZ_DEFAULT_MINIMUM);
1849 	if (n >= (int)sizeof(str) || n < 0) {
1850 		return ISC_R_NOSPACE;
1851 	}
1852 	return dns_sdlz_putrr(lookup, "SOA", SDLZ_DEFAULT_TTL, str);
1853 }
1854 
1855 isc_result_t
1856 dns_sdlzregister(const char *drivername, const dns_sdlzmethods_t *methods,
1857 		 void *driverarg, unsigned int flags, isc_mem_t *mctx,
1858 		 dns_sdlzimplementation_t **sdlzimp) {
1859 	dns_sdlzimplementation_t *imp;
1860 	isc_result_t result;
1861 
1862 	/*
1863 	 * Performs checks to make sure data is as we expect it to be.
1864 	 */
1865 	REQUIRE(drivername != NULL);
1866 	REQUIRE(methods != NULL);
1867 	REQUIRE(methods->findzone != NULL);
1868 	REQUIRE(methods->lookup != NULL);
1869 	REQUIRE(mctx != NULL);
1870 	REQUIRE(sdlzimp != NULL && *sdlzimp == NULL);
1871 	REQUIRE((flags &
1872 		 ~(DNS_SDLZFLAG_RELATIVEOWNER | DNS_SDLZFLAG_RELATIVERDATA |
1873 		   DNS_SDLZFLAG_THREADSAFE)) == 0);
1874 
1875 	/* Write debugging message to log */
1876 	sdlz_log(ISC_LOG_DEBUG(2), "Registering SDLZ driver '%s'", drivername);
1877 
1878 	/*
1879 	 * Allocate memory for a sdlz_implementation object.  Error if
1880 	 * we cannot.
1881 	 */
1882 	imp = isc_mem_get(mctx, sizeof(*imp));
1883 
1884 	/* Store the data passed into this method */
1885 	*imp = (dns_sdlzimplementation_t){
1886 		.methods = methods,
1887 		.driverarg = driverarg,
1888 		.flags = flags,
1889 	};
1890 
1891 	/* attach the new sdlz_implementation object to a memory context */
1892 	isc_mem_attach(mctx, &imp->mctx);
1893 
1894 	/*
1895 	 * initialize the driver lock, error if we cannot
1896 	 * (used if a driver does not support multiple threads)
1897 	 */
1898 	isc_mutex_init(&imp->driverlock);
1899 
1900 	/*
1901 	 * register the DLZ driver.  Pass in our "extra" sdlz information as
1902 	 * a driverarg.  (that's why we stored the passed in driver arg in our
1903 	 * sdlz_implementation structure)  Also, store the dlz_implementation
1904 	 * structure in our sdlz_implementation.
1905 	 */
1906 	result = dns_dlzregister(drivername, &sdlzmethods, imp, mctx,
1907 				 &imp->dlz_imp);
1908 
1909 	/* if registration fails, cleanup and get outta here. */
1910 	if (result != ISC_R_SUCCESS) {
1911 		goto cleanup_mutex;
1912 	}
1913 
1914 	*sdlzimp = imp;
1915 
1916 	return ISC_R_SUCCESS;
1917 
1918 cleanup_mutex:
1919 	/* destroy the driver lock, we don't need it anymore */
1920 	isc_mutex_destroy(&imp->driverlock);
1921 
1922 	/*
1923 	 * return the memory back to the available memory pool and
1924 	 * remove it from the memory context.
1925 	 */
1926 	isc_mem_putanddetach(&imp->mctx, imp, sizeof(*imp));
1927 	return result;
1928 }
1929 
1930 void
1931 dns_sdlzunregister(dns_sdlzimplementation_t **sdlzimp) {
1932 	dns_sdlzimplementation_t *imp;
1933 
1934 	/* Write debugging message to log */
1935 	sdlz_log(ISC_LOG_DEBUG(2), "Unregistering SDLZ driver.");
1936 
1937 	/*
1938 	 * Performs checks to make sure data is as we expect it to be.
1939 	 */
1940 	REQUIRE(sdlzimp != NULL && *sdlzimp != NULL);
1941 
1942 	imp = *sdlzimp;
1943 	*sdlzimp = NULL;
1944 
1945 	/* Unregister the DLZ driver implementation */
1946 	dns_dlzunregister(&imp->dlz_imp);
1947 
1948 	/* destroy the driver lock, we don't need it anymore */
1949 	isc_mutex_destroy(&imp->driverlock);
1950 
1951 	/*
1952 	 * return the memory back to the available memory pool and
1953 	 * remove it from the memory context.
1954 	 */
1955 	isc_mem_putanddetach(&imp->mctx, imp, sizeof(dns_sdlzimplementation_t));
1956 }
1957 
1958 isc_result_t
1959 dns_sdlz_setdb(dns_dlzdb_t *dlzdatabase, dns_rdataclass_t rdclass,
1960 	       const dns_name_t *name, dns_db_t **dbp) {
1961 	isc_result_t result;
1962 
1963 	result = dns_sdlzcreateDBP(dlzdatabase->mctx,
1964 				   dlzdatabase->implementation->driverarg,
1965 				   dlzdatabase->dbdata, name, rdclass, dbp);
1966 	return result;
1967 }
1968