1 /*
2  * Copyright (C) 2004-2012, 2014  Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (C) 1999-2003  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: rdataset.h,v 1.72 2011/06/08 22:13:51 each Exp $ */
19 
20 #ifndef DNS_RDATASET_H
21 #define DNS_RDATASET_H 1
22 
23 /*****
24  ***** Module Info
25  *****/
26 
27 /*! \file dns/rdataset.h
28  * \brief
29  * A DNS rdataset is a handle that can be associated with a collection of
30  * rdata all having a common owner name, class, and type.
31  *
32  * The dns_rdataset_t type is like a "virtual class".  To actually use
33  * rdatasets, an implementation of the method suite (e.g. "slabbed rdata") is
34  * required.
35  *
36  * XXX <more> XXX
37  *
38  * MP:
39  *\li	Clients of this module must impose any required synchronization.
40  *
41  * Reliability:
42  *\li	No anticipated impact.
43  *
44  * Resources:
45  *\li	TBS
46  *
47  * Security:
48  *\li	No anticipated impact.
49  *
50  * Standards:
51  *\li	None.
52  */
53 
54 #include <isc/lang.h>
55 #include <isc/magic.h>
56 #include <isc/stdtime.h>
57 
58 #include <dns/types.h>
59 #include <dns/rdatastruct.h>
60 
61 ISC_LANG_BEGINDECLS
62 
63 typedef enum {
64 	dns_rdatasetadditional_fromauth,
65 	dns_rdatasetadditional_fromcache,
66 	dns_rdatasetadditional_fromglue
67 } dns_rdatasetadditional_t;
68 
69 typedef struct dns_rdatasetmethods {
70 	void			(*disassociate)(dns_rdataset_t *rdataset);
71 	isc_result_t		(*first)(dns_rdataset_t *rdataset);
72 	isc_result_t		(*next)(dns_rdataset_t *rdataset);
73 	void			(*current)(dns_rdataset_t *rdataset,
74 					   dns_rdata_t *rdata);
75 	void			(*clone)(dns_rdataset_t *source,
76 					 dns_rdataset_t *target);
77 	unsigned int		(*count)(dns_rdataset_t *rdataset);
78 	isc_result_t		(*addnoqname)(dns_rdataset_t *rdataset,
79 					      dns_name_t *name);
80 	isc_result_t		(*getnoqname)(dns_rdataset_t *rdataset,
81 					      dns_name_t *name,
82 					      dns_rdataset_t *neg,
83 					      dns_rdataset_t *negsig);
84 	isc_result_t		(*addclosest)(dns_rdataset_t *rdataset,
85 					      dns_name_t *name);
86 	isc_result_t		(*getclosest)(dns_rdataset_t *rdataset,
87 					      dns_name_t *name,
88 					      dns_rdataset_t *neg,
89 					      dns_rdataset_t *negsig);
90 	isc_result_t		(*getadditional)(dns_rdataset_t *rdataset,
91 						 dns_rdatasetadditional_t type,
92 						 dns_rdatatype_t qtype,
93 						 dns_acache_t *acache,
94 						 dns_zone_t **zonep,
95 						 dns_db_t **dbp,
96 						 dns_dbversion_t **versionp,
97 						 dns_dbnode_t **nodep,
98 						 dns_name_t *fname,
99 						 dns_message_t *msg,
100 						 isc_stdtime_t now);
101 	isc_result_t		(*setadditional)(dns_rdataset_t *rdataset,
102 						 dns_rdatasetadditional_t type,
103 						 dns_rdatatype_t qtype,
104 						 dns_acache_t *acache,
105 						 dns_zone_t *zone,
106 						 dns_db_t *db,
107 						 dns_dbversion_t *version,
108 						 dns_dbnode_t *node,
109 						 dns_name_t *fname);
110 	isc_result_t		(*putadditional)(dns_acache_t *acache,
111 						 dns_rdataset_t *rdataset,
112 						 dns_rdatasetadditional_t type,
113 						 dns_rdatatype_t qtype);
114 	void			(*settrust)(dns_rdataset_t *rdataset,
115 					    dns_trust_t trust);
116 	void			(*expire)(dns_rdataset_t *rdataset);
117 } dns_rdatasetmethods_t;
118 
119 #define DNS_RDATASET_MAGIC	       ISC_MAGIC('D','N','S','R')
120 #define DNS_RDATASET_VALID(set)	       ISC_MAGIC_VALID(set, DNS_RDATASET_MAGIC)
121 
122 /*%
123  * Direct use of this structure by clients is strongly discouraged, except
124  * for the 'link' field which may be used however the client wishes.  The
125  * 'private', 'current', and 'index' fields MUST NOT be changed by clients.
126  * rdataset implementations may change any of the fields.
127  */
128 struct dns_rdataset {
129 	unsigned int			magic;		/* XXX ? */
130 	dns_rdatasetmethods_t *		methods;
131 	ISC_LINK(dns_rdataset_t)	link;
132 	/*
133 	 * XXX do we need these, or should they be retrieved by methods?
134 	 * Leaning towards the latter, since they are not frequently required
135 	 * once you have the rdataset.
136 	 */
137 	dns_rdataclass_t		rdclass;
138 	dns_rdatatype_t			type;
139 	dns_ttl_t			ttl;
140 	dns_trust_t			trust;
141 	dns_rdatatype_t			covers;
142 	/*
143 	 * attributes
144 	 */
145 	unsigned int			attributes;
146 	/*%
147 	 * the counter provides the starting point in the "cyclic" order.
148 	 * The value ISC_UINT32_MAX has a special meaning of "picking up a
149 	 * random value." in order to take care of databases that do not
150 	 * increment the counter.
151 	 */
152 	isc_uint32_t			count;
153 	/*
154 	 * This RRSIG RRset should be re-generated around this time.
155 	 * Only valid if DNS_RDATASETATTR_RESIGN is set in attributes.
156 	 */
157 	isc_stdtime_t			resign;
158 	/*@{*/
159 	/*%
160 	 * These are for use by the rdataset implementation, and MUST NOT
161 	 * be changed by clients.
162 	 */
163 	void *				private1;
164 	void *				private2;
165 	void *				private3;
166 	unsigned int			privateuint4;
167 	void *				private5;
168 	void *				private6;
169 	void *				private7;
170 	/*@}*/
171 
172 };
173 
174 /*!
175  * \def DNS_RDATASETATTR_RENDERED
176  *	Used by message.c to indicate that the rdataset was rendered.
177  *
178  * \def DNS_RDATASETATTR_TTLADJUSTED
179  *	Used by message.c to indicate that the rdataset's rdata had differing
180  *	TTL values, and the rdataset->ttl holds the smallest.
181  *
182  * \def DNS_RDATASETATTR_LOADORDER
183  *	Output the RRset in load order.
184  */
185 
186 #define DNS_RDATASETATTR_QUESTION	0x00000001
187 #define DNS_RDATASETATTR_RENDERED	0x00000002	/*%< Used by message.c */
188 #define DNS_RDATASETATTR_ANSWERED	0x00000004	/*%< Used by server. */
189 #define DNS_RDATASETATTR_CACHE		0x00000008	/*%< Used by resolver. */
190 #define DNS_RDATASETATTR_ANSWER		0x00000010	/*%< Used by resolver. */
191 #define DNS_RDATASETATTR_ANSWERSIG	0x00000020	/*%< Used by resolver. */
192 #define DNS_RDATASETATTR_EXTERNAL	0x00000040	/*%< Used by resolver. */
193 #define DNS_RDATASETATTR_NCACHE		0x00000080	/*%< Used by resolver. */
194 #define DNS_RDATASETATTR_CHAINING	0x00000100	/*%< Used by resolver. */
195 #define DNS_RDATASETATTR_TTLADJUSTED	0x00000200	/*%< Used by message.c */
196 #define DNS_RDATASETATTR_FIXEDORDER	0x00000400
197 #define DNS_RDATASETATTR_RANDOMIZE	0x00000800
198 #define DNS_RDATASETATTR_CHASE		0x00001000	/*%< Used by resolver. */
199 #define DNS_RDATASETATTR_NXDOMAIN	0x00002000
200 #define DNS_RDATASETATTR_NOQNAME	0x00004000
201 #define DNS_RDATASETATTR_CHECKNAMES	0x00008000	/*%< Used by resolver. */
202 #define DNS_RDATASETATTR_REQUIRED	0x00010000
203 #define DNS_RDATASETATTR_REQUIREDGLUE	DNS_RDATASETATTR_REQUIRED
204 #define DNS_RDATASETATTR_LOADORDER	0x00020000
205 #define DNS_RDATASETATTR_RESIGN		0x00040000
206 #define DNS_RDATASETATTR_CLOSEST	0x00080000
207 #define DNS_RDATASETATTR_OPTOUT		0x00100000	/*%< OPTOUT proof */
208 #define DNS_RDATASETATTR_NEGATIVE	0x00200000
209 
210 /*%
211  * _OMITDNSSEC:
212  * 	Omit DNSSEC records when rendering ncache records.
213  */
214 #define DNS_RDATASETTOWIRE_OMITDNSSEC	0x0001
215 
216 void
217 dns_rdataset_init(dns_rdataset_t *rdataset);
218 /*%<
219  * Make 'rdataset' a valid, disassociated rdataset.
220  *
221  * Requires:
222  *\li	'rdataset' is not NULL.
223  *
224  * Ensures:
225  *\li	'rdataset' is a valid, disassociated rdataset.
226  */
227 
228 void
229 dns_rdataset_invalidate(dns_rdataset_t *rdataset);
230 /*%<
231  * Invalidate 'rdataset'.
232  *
233  * Requires:
234  *\li	'rdataset' is a valid, disassociated rdataset.
235  *
236  * Ensures:
237  *\li	If assertion checking is enabled, future attempts to use 'rdataset'
238  *	without initializing it will cause an assertion failure.
239  */
240 
241 void
242 dns_rdataset_disassociate(dns_rdataset_t *rdataset);
243 /*%<
244  * Disassociate 'rdataset' from its rdata, allowing it to be reused.
245  *
246  * Notes:
247  *\li	The client must ensure it has no references to rdata in the rdataset
248  *	before disassociating.
249  *
250  * Requires:
251  *\li	'rdataset' is a valid, associated rdataset.
252  *
253  * Ensures:
254  *\li	'rdataset' is a valid, disassociated rdataset.
255  */
256 
257 isc_boolean_t
258 dns_rdataset_isassociated(dns_rdataset_t *rdataset);
259 /*%<
260  * Is 'rdataset' associated?
261  *
262  * Requires:
263  *\li	'rdataset' is a valid rdataset.
264  *
265  * Returns:
266  *\li	#ISC_TRUE			'rdataset' is associated.
267  *\li	#ISC_FALSE			'rdataset' is not associated.
268  */
269 
270 void
271 dns_rdataset_makequestion(dns_rdataset_t *rdataset, dns_rdataclass_t rdclass,
272 			  dns_rdatatype_t type);
273 /*%<
274  * Make 'rdataset' a valid, associated, question rdataset, with a
275  * question class of 'rdclass' and type 'type'.
276  *
277  * Notes:
278  *\li	Question rdatasets have a class and type, but no rdata.
279  *
280  * Requires:
281  *\li	'rdataset' is a valid, disassociated rdataset.
282  *
283  * Ensures:
284  *\li	'rdataset' is a valid, associated, question rdataset.
285  */
286 
287 void
288 dns_rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target);
289 /*%<
290  * Make 'target' refer to the same rdataset as 'source'.
291  *
292  * Requires:
293  *\li	'source' is a valid, associated rdataset.
294  *
295  *\li	'target' is a valid, dissociated rdataset.
296  *
297  * Ensures:
298  *\li	'target' references the same rdataset as 'source'.
299  */
300 
301 unsigned int
302 dns_rdataset_count(dns_rdataset_t *rdataset);
303 /*%<
304  * Return the number of records in 'rdataset'.
305  *
306  * Requires:
307  *\li	'rdataset' is a valid, associated rdataset.
308  *
309  * Returns:
310  *\li	The number of records in 'rdataset'.
311  */
312 
313 isc_result_t
314 dns_rdataset_first(dns_rdataset_t *rdataset);
315 /*%<
316  * Move the rdata cursor to the first rdata in the rdataset (if any).
317  *
318  * Requires:
319  *\li	'rdataset' is a valid, associated rdataset.
320  *
321  * Returns:
322  *\li	#ISC_R_SUCCESS
323  *\li	#ISC_R_NOMORE			There are no rdata in the set.
324  */
325 
326 isc_result_t
327 dns_rdataset_next(dns_rdataset_t *rdataset);
328 /*%<
329  * Move the rdata cursor to the next rdata in the rdataset (if any).
330  *
331  * Requires:
332  *\li	'rdataset' is a valid, associated rdataset.
333  *
334  * Returns:
335  *\li	#ISC_R_SUCCESS
336  *\li	#ISC_R_NOMORE			There are no more rdata in the set.
337  */
338 
339 void
340 dns_rdataset_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata);
341 /*%<
342  * Make 'rdata' refer to the current rdata.
343  *
344  * Notes:
345  *
346  *\li	The data returned in 'rdata' is valid for the life of the
347  *	rdataset; in particular, subsequent changes in the cursor position
348  *	do not invalidate 'rdata'.
349  *
350  * Requires:
351  *\li	'rdataset' is a valid, associated rdataset.
352  *
353  *\li	The rdata cursor of 'rdataset' is at a valid location (i.e. the
354  *	result of last call to a cursor movement command was ISC_R_SUCCESS).
355  *
356  * Ensures:
357  *\li	'rdata' refers to the rdata at the rdata cursor location of
358  *\li	'rdataset'.
359  */
360 
361 isc_result_t
362 dns_rdataset_totext(dns_rdataset_t *rdataset,
363 		    dns_name_t *owner_name,
364 		    isc_boolean_t omit_final_dot,
365 		    isc_boolean_t question,
366 		    isc_buffer_t *target);
367 /*%<
368  * Convert 'rdataset' to text format, storing the result in 'target'.
369  *
370  * Notes:
371  *\li	The rdata cursor position will be changed.
372  *
373  *\li	The 'question' flag should normally be #ISC_FALSE.  If it is
374  *	#ISC_TRUE, the TTL and rdata fields are not printed.  This is
375  *	for use when printing an rdata representing a question section.
376  *
377  *\li	This interface is deprecated; use dns_master_rdatasettottext()
378  * 	and/or dns_master_questiontotext() instead.
379  *
380  * Requires:
381  *\li	'rdataset' is a valid rdataset.
382  *
383  *\li	'rdataset' is not empty.
384  */
385 
386 isc_result_t
387 dns_rdataset_towire(dns_rdataset_t *rdataset,
388 		    dns_name_t *owner_name,
389 		    dns_compress_t *cctx,
390 		    isc_buffer_t *target,
391 		    unsigned int options,
392 		    unsigned int *countp);
393 /*%<
394  * Convert 'rdataset' to wire format, compressing names as specified
395  * in 'cctx', and storing the result in 'target'.
396  *
397  * Notes:
398  *\li	The rdata cursor position will be changed.
399  *
400  *\li	The number of RRs added to target will be added to *countp.
401  *
402  * Requires:
403  *\li	'rdataset' is a valid rdataset.
404  *
405  *\li	'rdataset' is not empty.
406  *
407  *\li	'countp' is a valid pointer.
408  *
409  * Ensures:
410  *\li	On a return of ISC_R_SUCCESS, 'target' contains a wire format
411  *	for the data contained in 'rdataset'.  Any error return leaves
412  *	the buffer unchanged.
413  *
414  *\li	*countp has been incremented by the number of RRs added to
415  *	target.
416  *
417  * Returns:
418  *\li	#ISC_R_SUCCESS		- all ok
419  *\li	#ISC_R_NOSPACE		- 'target' doesn't have enough room
420  *
421  *\li	Any error returned by dns_rdata_towire(), dns_rdataset_next(),
422  *	dns_name_towire().
423  */
424 
425 isc_result_t
426 dns_rdataset_towiresorted(dns_rdataset_t *rdataset,
427 			  const dns_name_t *owner_name,
428 			  dns_compress_t *cctx,
429 			  isc_buffer_t *target,
430 			  dns_rdatasetorderfunc_t order,
431 			  const void *order_arg,
432 			  unsigned int options,
433 			  unsigned int *countp);
434 /*%<
435  * Like dns_rdataset_towire(), but sorting the rdatasets according to
436  * the integer value returned by 'order' when called with the rdataset
437  * and 'order_arg' as arguments.
438  *
439  * Requires:
440  *\li	All the requirements of dns_rdataset_towire(), and
441  *	that order_arg is NULL if and only if order is NULL.
442  */
443 
444 isc_result_t
445 dns_rdataset_towirepartial(dns_rdataset_t *rdataset,
446 			   const dns_name_t *owner_name,
447 			   dns_compress_t *cctx,
448 			   isc_buffer_t *target,
449 			   dns_rdatasetorderfunc_t order,
450 			   const void *order_arg,
451 			   unsigned int options,
452 			   unsigned int *countp,
453 			   void **state);
454 /*%<
455  * Like dns_rdataset_towiresorted() except that a partial rdataset
456  * may be written.
457  *
458  * Requires:
459  *\li	All the requirements of dns_rdataset_towiresorted().
460  *	If 'state' is non NULL then the current position in the
461  *	rdataset will be remembered if the rdataset in not
462  *	completely written and should be passed on on subsequent
463  *	calls (NOT CURRENTLY IMPLEMENTED).
464  *
465  * Returns:
466  *\li	#ISC_R_SUCCESS if all of the records were written.
467  *\li	#ISC_R_NOSPACE if unable to fit in all of the records. *countp
468  *		      will be updated to reflect the number of records
469  *		      written.
470  */
471 
472 isc_result_t
473 dns_rdataset_additionaldata(dns_rdataset_t *rdataset,
474 			    dns_additionaldatafunc_t add, void *arg);
475 /*%<
476  * For each rdata in rdataset, call 'add' for each name and type in the
477  * rdata which is subject to additional section processing.
478  *
479  * Requires:
480  *
481  *\li	'rdataset' is a valid, non-question rdataset.
482  *
483  *\li	'add' is a valid dns_additionaldatafunc_t
484  *
485  * Ensures:
486  *
487  *\li	If successful, dns_rdata_additionaldata() will have been called for
488  *	each rdata in 'rdataset'.
489  *
490  *\li	If a call to dns_rdata_additionaldata() is not successful, the
491  *	result returned will be the result of dns_rdataset_additionaldata().
492  *
493  * Returns:
494  *
495  *\li	#ISC_R_SUCCESS
496  *
497  *\li	Any error that dns_rdata_additionaldata() can return.
498  */
499 
500 isc_result_t
501 dns_rdataset_getnoqname(dns_rdataset_t *rdataset, dns_name_t *name,
502 			dns_rdataset_t *neg, dns_rdataset_t *negsig);
503 /*%<
504  * Return the noqname proof for this record.
505  *
506  * Requires:
507  *\li	'rdataset' to be valid and #DNS_RDATASETATTR_NOQNAME to be set.
508  *\li	'name' to be valid.
509  *\li	'neg' and 'negsig' to be valid and not associated.
510  */
511 
512 isc_result_t
513 dns_rdataset_addnoqname(dns_rdataset_t *rdataset, dns_name_t *name);
514 /*%<
515  * Associate a noqname proof with this record.
516  * Sets #DNS_RDATASETATTR_NOQNAME if successful.
517  * Adjusts the 'rdataset->ttl' to minimum of the 'rdataset->ttl' and
518  * the 'nsec'/'nsec3' and 'rrsig(nsec)'/'rrsig(nsec3)' ttl.
519  *
520  * Requires:
521  *\li	'rdataset' to be valid and #DNS_RDATASETATTR_NOQNAME to be set.
522  *\li	'name' to be valid and have NSEC or NSEC3 and associated RRSIG
523  *	 rdatasets.
524  */
525 
526 isc_result_t
527 dns_rdataset_getclosest(dns_rdataset_t *rdataset, dns_name_t *name,
528 			dns_rdataset_t *nsec, dns_rdataset_t *nsecsig);
529 /*%<
530  * Return the closest encloser for this record.
531  *
532  * Requires:
533  *\li	'rdataset' to be valid and #DNS_RDATASETATTR_CLOSEST to be set.
534  *\li	'name' to be valid.
535  *\li	'nsec' and 'nsecsig' to be valid and not associated.
536  */
537 
538 isc_result_t
539 dns_rdataset_addclosest(dns_rdataset_t *rdataset, dns_name_t *name);
540 /*%<
541  * Associate a closest encloset proof with this record.
542  * Sets #DNS_RDATASETATTR_CLOSEST if successful.
543  * Adjusts the 'rdataset->ttl' to minimum of the 'rdataset->ttl' and
544  * the 'nsec' and 'rrsig(nsec)' ttl.
545  *
546  * Requires:
547  *\li	'rdataset' to be valid and #DNS_RDATASETATTR_CLOSEST to be set.
548  *\li	'name' to be valid and have NSEC3 and RRSIG(NSEC3) rdatasets.
549  */
550 
551 isc_result_t
552 dns_rdataset_getadditional(dns_rdataset_t *rdataset,
553 			   dns_rdatasetadditional_t type,
554 			   dns_rdatatype_t qtype,
555 			   dns_acache_t *acache,
556 			   dns_zone_t **zonep,
557 			   dns_db_t **dbp,
558 			   dns_dbversion_t **versionp,
559 			   dns_dbnode_t **nodep,
560 			   dns_name_t *fname,
561 			   dns_message_t *msg,
562 			   isc_stdtime_t now);
563 /*%<
564  * Get cached additional information from the DB node for a particular
565  * 'rdataset.'  'type' is one of dns_rdatasetadditional_fromauth,
566  * dns_rdatasetadditional_fromcache, and dns_rdatasetadditional_fromglue,
567  * which specifies the origin of the information.  'qtype' is intended to
568  * be used for specifying a particular rdata type in the cached information.
569  *
570  * Requires:
571  * \li	'rdataset' is a valid rdataset.
572  * \li	'acache' can be NULL, in which case this function will simply return
573  * 	ISC_R_FAILURE.
574  * \li	For the other pointers, see dns_acache_getentry().
575  *
576  * Ensures:
577  * \li	See dns_acache_getentry().
578  *
579  * Returns:
580  * \li	#ISC_R_SUCCESS
581  * \li	#ISC_R_FAILURE	- additional information caching is not supported.
582  * \li	#ISC_R_NOTFOUND	- the corresponding DB node has not cached additional
583  *			  information for 'rdataset.'
584  * \li	Any error that dns_acache_getentry() can return.
585  */
586 
587 isc_result_t
588 dns_rdataset_setadditional(dns_rdataset_t *rdataset,
589 			   dns_rdatasetadditional_t type,
590 			   dns_rdatatype_t qtype,
591 			   dns_acache_t *acache,
592 			   dns_zone_t *zone,
593 			   dns_db_t *db,
594 			   dns_dbversion_t *version,
595 			   dns_dbnode_t *node,
596 			   dns_name_t *fname);
597 /*%<
598  * Set cached additional information to the DB node for a particular
599  * 'rdataset.'  See dns_rdataset_getadditional for the semantics of 'type'
600  * and 'qtype'.
601  *
602  * Requires:
603  * \li	'rdataset' is a valid rdataset.
604  * \li	'acache' can be NULL, in which case this function will simply return
605  *	ISC_R_FAILURE.
606  * \li	For the other pointers, see dns_acache_setentry().
607  *
608  * Ensures:
609  * \li	See dns_acache_setentry().
610  *
611  * Returns:
612  * \li	#ISC_R_SUCCESS
613  * \li	#ISC_R_FAILURE	- additional information caching is not supported.
614  * \li	#ISC_R_NOMEMORY
615  * \li	Any error that dns_acache_setentry() can return.
616  */
617 
618 isc_result_t
619 dns_rdataset_putadditional(dns_acache_t *acache,
620 			   dns_rdataset_t *rdataset,
621 			   dns_rdatasetadditional_t type,
622 			   dns_rdatatype_t qtype);
623 /*%<
624  * Discard cached additional information stored in the DB node for a particular
625  * 'rdataset.'  See dns_rdataset_getadditional for the semantics of 'type'
626  * and 'qtype'.
627  *
628  * Requires:
629  * \li	'rdataset' is a valid rdataset.
630  * \li	'acache' can be NULL, in which case this function will simply return
631  *	ISC_R_FAILURE.
632  *
633  * Ensures:
634  * \li	See dns_acache_cancelentry().
635  *
636  * Returns:
637  * \li	#ISC_R_SUCCESS
638  * \li	#ISC_R_FAILURE	- additional information caching is not supported.
639  * \li	#ISC_R_NOTFOUND	- the corresponding DB node has not cached additional
640  *			  information for 'rdataset.'
641  */
642 
643 void
644 dns_rdataset_settrust(dns_rdataset_t *rdataset, dns_trust_t trust);
645 /*%<
646  * Set the trust of the 'rdataset' to trust in any in the backing database.
647  * The local trust level of 'rdataset' is also set.
648  */
649 
650 void
651 dns_rdataset_expire(dns_rdataset_t *rdataset);
652 /*%<
653  * Mark the rdataset to be expired in the backing database.
654  */
655 
656 void
657 dns_rdataset_trimttl(dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset,
658 		     dns_rdata_rrsig_t *rrsig, isc_stdtime_t now,
659 		     isc_boolean_t acceptexpired);
660 /*%<
661  * Trim the ttl of 'rdataset' and 'sigrdataset' so that they will expire
662  * at or before 'rrsig->expiretime'.  If 'acceptexpired' is true and the
663  * signature has expired or will expire in the next 120 seconds, limit
664  * the ttl to be no more than 120 seconds.
665  *
666  * The ttl is further limited by the original ttl as stored in 'rrsig'
667  * and the original ttl values of 'rdataset' and 'sigrdataset'.
668  *
669  * Requires:
670  * \li	'rdataset' is a valid rdataset.
671  * \li	'sigrdataset' is a valid rdataset.
672  * \li	'rrsig' is non NULL.
673  */
674 
675 const char *
676 dns_trust_totext(dns_trust_t trust);
677 /*%<
678  * Display trust in textual form.
679  */
680 
681 ISC_LANG_ENDDECLS
682 
683 #endif /* DNS_RDATASET_H */
684