2 * rr.h - resource record definitions
4 * a Net::DNS like library for C
6 * (c) NLnet Labs, 2005-2006
8 * See the file LICENSE for the license
14 * Contains the definition of ldns_rr and functions to manipulate those.
21 #include <ldns/common.h>
22 #include <ldns/rdata.h>
23 #include <ldns/buffer.h>
24 #include <ldns/error.h>
30 /** Maximum length of a dname label */
31 #define LDNS_MAX_LABELLEN 63
32 /** Maximum length of a complete dname */
33 #define LDNS_MAX_DOMAINLEN 255
34 /** Maximum number of pointers in 1 dname */
35 #define LDNS_MAX_POINTERS 65535
36 /** The bytes TTL, CLASS and length use up in an rr */
37 #define LDNS_RR_OVERHEAD 10
39 /* The first fields are 'common' and can be referenced instantly */
40 #define LDNS_RDATA_FIELD_DESCRIPTORS_COMMON 52
45 * The different RR classes.
47 enum ldns_enum_rr_class
53 /** Hesiod (Dyer 87) */
55 /** None class, dynamic update */
56 LDNS_RR_CLASS_NONE = 254,
58 LDNS_RR_CLASS_ANY = 255,
60 LDNS_RR_CLASS_FIRST = 0,
61 LDNS_RR_CLASS_LAST = 65535,
62 LDNS_RR_CLASS_COUNT = LDNS_RR_CLASS_LAST - LDNS_RR_CLASS_FIRST + 1
64 typedef enum ldns_enum_rr_class ldns_rr_class;
67 * Used to specify whether compression is allowed.
69 enum ldns_enum_rr_compress
71 /** compression is allowed */
75 typedef enum ldns_enum_rr_compress ldns_rr_compress;
78 * The different RR types.
80 enum ldns_enum_rr_type
84 /** an authoritative name server */
86 /** a mail destination (Obsolete - use MX) */
88 /** a mail forwarder (Obsolete - use MX) */
90 /** the canonical name for an alias */
91 LDNS_RR_TYPE_CNAME = 5,
92 /** marks the start of a zone of authority */
94 /** a mailbox domain name (EXPERIMENTAL) */
96 /** a mail group member (EXPERIMENTAL) */
98 /** a mail rename domain name (EXPERIMENTAL) */
100 /** a null RR (EXPERIMENTAL) */
101 LDNS_RR_TYPE_NULL = 10,
102 /** a well known service description */
103 LDNS_RR_TYPE_WKS = 11,
104 /** a domain name pointer */
105 LDNS_RR_TYPE_PTR = 12,
106 /** host information */
107 LDNS_RR_TYPE_HINFO = 13,
108 /** mailbox or mail list information */
109 LDNS_RR_TYPE_MINFO = 14,
111 LDNS_RR_TYPE_MX = 15,
113 LDNS_RR_TYPE_TXT = 16,
115 LDNS_RR_TYPE_RP = 17,
117 LDNS_RR_TYPE_AFSDB = 18,
119 LDNS_RR_TYPE_X25 = 19,
121 LDNS_RR_TYPE_ISDN = 20,
123 LDNS_RR_TYPE_RT = 21,
125 LDNS_RR_TYPE_NSAP = 22,
127 LDNS_RR_TYPE_NSAP_PTR = 23,
129 LDNS_RR_TYPE_SIG = 24,
131 LDNS_RR_TYPE_KEY = 25,
133 LDNS_RR_TYPE_PX = 26,
135 LDNS_RR_TYPE_GPOS = 27,
137 LDNS_RR_TYPE_AAAA = 28,
138 /** LOC record RFC1876 */
139 LDNS_RR_TYPE_LOC = 29,
141 LDNS_RR_TYPE_NXT = 30,
142 /** draft-ietf-nimrod-dns-01.txt */
143 LDNS_RR_TYPE_EID = 31,
144 /** draft-ietf-nimrod-dns-01.txt */
145 LDNS_RR_TYPE_NIMLOC = 32,
146 /** SRV record RFC2782 */
147 LDNS_RR_TYPE_SRV = 33,
148 /** http://www.jhsoft.com/rfc/af-saa-0069.000.rtf */
149 LDNS_RR_TYPE_ATMA = 34,
151 LDNS_RR_TYPE_NAPTR = 35,
153 LDNS_RR_TYPE_KX = 36,
155 LDNS_RR_TYPE_CERT = 37,
157 LDNS_RR_TYPE_A6 = 38,
159 LDNS_RR_TYPE_DNAME = 39,
160 /** dnsind-kitchen-sink-02.txt */
161 LDNS_RR_TYPE_SINK = 40,
162 /** Pseudo OPT record... */
163 LDNS_RR_TYPE_OPT = 41,
165 LDNS_RR_TYPE_APL = 42,
166 /** draft-ietf-dnsext-delegation */
167 LDNS_RR_TYPE_DS = 43,
168 /** SSH Key Fingerprint */
169 LDNS_RR_TYPE_SSHFP = 44,
170 /** draft-richardson-ipseckey-rr-11.txt */
171 LDNS_RR_TYPE_IPSECKEY = 45,
172 /** draft-ietf-dnsext-dnssec-25 */
173 LDNS_RR_TYPE_RRSIG = 46,
174 LDNS_RR_TYPE_NSEC = 47,
175 LDNS_RR_TYPE_DNSKEY = 48,
176 LDNS_RR_TYPE_DHCID = 49,
178 LDNS_RR_TYPE_NSEC3 = 50,
179 LDNS_RR_TYPE_NSEC3PARAMS = 51,
181 /** draft-ietf-dnsop-trust-history */
182 LDNS_RR_TYPE_TALINK = 58,
184 LDNS_RR_TYPE_SPF = 99,
186 LDNS_RR_TYPE_UINFO = 100,
187 LDNS_RR_TYPE_UID = 101,
188 LDNS_RR_TYPE_GID = 102,
189 LDNS_RR_TYPE_UNSPEC = 103,
191 LDNS_RR_TYPE_TSIG = 250,
192 LDNS_RR_TYPE_IXFR = 251,
193 LDNS_RR_TYPE_AXFR = 252,
194 /** A request for mailbox-related records (MB, MG or MR) */
195 LDNS_RR_TYPE_MAILB = 253,
196 /** A request for mail agent RRs (Obsolete - see MX) */
197 LDNS_RR_TYPE_MAILA = 254,
198 /** any type (wildcard) */
199 LDNS_RR_TYPE_ANY = 255,
201 /* RFC 4431, 5074, DNSSEC Lookaside Validation */
202 LDNS_RR_TYPE_DLV = 32769,
204 /* type codes from nsec3 experimental phase
205 LDNS_RR_TYPE_NSEC3 = 65324,
206 LDNS_RR_TYPE_NSEC3PARAMS = 65325, */
207 LDNS_RR_TYPE_FIRST = 0,
208 LDNS_RR_TYPE_LAST = 65535,
209 LDNS_RR_TYPE_COUNT = LDNS_RR_TYPE_LAST - LDNS_RR_TYPE_FIRST + 1
211 typedef enum ldns_enum_rr_type ldns_rr_type;
216 * This is the basic DNS element that contains actual data
222 All RRs have the same top level format shown below:
225 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
226 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
231 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
233 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
235 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
238 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
240 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--|
243 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
247 NAME an owner name, i.e., the name of the node to which this
248 resource record pertains.
250 TYPE two octets containing one of the RR TYPE codes.
252 CLASS two octets containing one of the RR CLASS codes.
254 TTL a 32 bit signed integer that specifies the time interval
255 that the resource record may be cached before the source
256 of the information should again be consulted. Zero
257 values are interpreted to mean that the RR can only be
258 used for the transaction in progress, and should not be
259 cached. For example, SOA records are always distributed
260 with a zero TTL to prohibit caching. Zero values can
261 also be used for extremely volatile data.
263 RDLENGTH an unsigned 16 bit integer that specifies the length in
264 octets of the RDATA field.
266 RDATA a variable length string of octets that describes the
267 resource. The format of this information varies
268 according to the TYPE and CLASS of the resource record.
271 * The actual amount and type of rdata fields depend on the RR type of the
272 * RR, and can be found by using \ref ldns_rr_descriptor functions.
274 struct ldns_struct_rr
276 /** Owner name, uncompressed */
280 /** Number of data fields */
282 /** the type of the RR. A, MX etc. */
283 ldns_rr_type _rr_type;
284 /** Class of the resource record. */
285 ldns_rr_class _rr_class;
286 /* everything in the rdata is in network order */
287 /** The array of rdata's */
288 ldns_rdf **_rdata_fields;
289 /** question rr [it would be nicer if thous is after _rd_count]
290 ABI change: Fix this in next major release
294 typedef struct ldns_struct_rr ldns_rr;
297 * List or Set of Resource Records
299 * Contains a list of rr's <br>
300 * No official RFC-like checks are made
302 struct ldns_struct_rr_list
308 typedef struct ldns_struct_rr_list ldns_rr_list;
311 * Contains all information about resource record types.
313 * This structure contains, for all rr types, the rdata fields that are defined.
315 struct ldns_struct_rr_descriptor
317 /** Type of the RR that is described here */
319 /** Textual name of the RR type. */
321 /** Minimum number of rdata fields in the RRs of this type. */
323 /** Maximum number of rdata fields in the RRs of this type. */
325 /** Wireformat specification for the rr, i.e. the types of rdata fields in their respective order. */
326 const ldns_rdf_type *_wireformat;
327 /** Special rdf types */
328 ldns_rdf_type _variable;
329 /** Specifies whether compression can be used for dnames in this RR type. */
330 ldns_rr_compress _compress;
331 /** The number of DNAMEs in the _wireformat string, for parsing. */
332 uint8_t _dname_count;
334 typedef struct ldns_struct_rr_descriptor ldns_rr_descriptor;
337 * creates a new rr structure.
340 ldns_rr* ldns_rr_new(void);
343 * creates a new rr structure, based on the given type.
344 * alloc enough space to hold all the rdf's
346 ldns_rr* ldns_rr_new_frm_type(ldns_rr_type t);
349 * frees an RR structure
350 * \param[in] *rr the RR to be freed
353 void ldns_rr_free(ldns_rr *rr);
356 * creates an rr from a string.
357 * The string should be a fully filled-in rr, like
358 * ownername <space> TTL <space> CLASS <space>
359 * TYPE <space> RDATA.
360 * \param[out] n the rr to return
361 * \param[in] str the string to convert
362 * \param[in] default_ttl default ttl value for the rr.
363 * If 0 DEF_TTL will be used
364 * \param[in] origin when the owner is relative add this.
365 * The caller must ldns_rdf_deep_free it.
366 * \param[out] prev the previous ownername. if this value is not NULL,
367 * the function overwrites this with the ownername found in this
368 * string. The caller must then ldns_rdf_deep_free it.
369 * \return a status msg describing an error or LDNS_STATUS_OK
371 ldns_status ldns_rr_new_frm_str(ldns_rr **n, const char *str,
372 uint32_t default_ttl, ldns_rdf *origin,
376 * creates an rr for the question section from a string, i.e.
377 * without RDATA fields
378 * Origin and previous RR functionality are the same as in
379 * ldns_rr_new_frm_str()
380 * \param[out] n the rr to return
381 * \param[in] str the string to convert
382 * \param[in] origin when the owner is relative add this.
383 * The caller must ldns_rdf_deep_free it.
384 * \param prev the previous ownername. the function overwrite this with
385 * the current found ownername. The caller must ldns_rdf_deep_free it.
386 * \return a status msg describing an error or LDNS_STATUS_OK
388 ldns_status ldns_rr_new_question_frm_str(ldns_rr **n, const char *str,
389 ldns_rdf *origin, ldns_rdf **prev);
392 * creates a new rr from a file containing a string.
393 * \param[out] rr the new rr
394 * \param[in] fp the file pointer to use
395 * \param[in] default_ttl pointer to a default ttl for the rr. If NULL DEF_TTL will be used
396 * the pointer will be updated if the file contains a $TTL directive
397 * \param[in] origin when the owner is relative add this
398 * the pointer will be updated if the file contains a $ORIGIN directive
399 * The caller must ldns_rdf_deep_free it.
400 * \param[in] prev when the owner is whitespaces use this as the * ownername
401 * the pointer will be updated after the call
402 * The caller must ldns_rdf_deep_free it.
403 * \return a ldns_status with an error or LDNS_STATUS_OK
405 ldns_status ldns_rr_new_frm_fp(ldns_rr **rr, FILE *fp, uint32_t *default_ttl, ldns_rdf **origin, ldns_rdf **prev);
408 * creates a new rr from a file containing a string.
409 * \param[out] rr the new rr
410 * \param[in] fp the file pointer to use
411 * \param[in] default_ttl a default ttl for the rr. If NULL DEF_TTL will be used
412 * the pointer will be updated if the file contains a $TTL directive
413 * \param[in] origin when the owner is relative add this
414 * the pointer will be updated if the file contains a $ORIGIN directive
415 * The caller must ldns_rdf_deep_free it.
416 * \param[in] line_nr pointer to an integer containing the current line number (for debugging purposes)
417 * \param[in] prev when the owner is whitespaces use this as the * ownername
418 * the pointer will be updated after the call
419 * The caller must ldns_rdf_deep_free it.
420 * \return a ldns_status with an error or LDNS_STATUS_OK
422 ldns_status ldns_rr_new_frm_fp_l(ldns_rr **rr, FILE *fp, uint32_t *default_ttl, ldns_rdf **origin, ldns_rdf **prev, int *line_nr);
425 * sets the owner in the rr structure.
426 * \param[in] *rr rr to operate on
427 * \param[in] *owner set to this owner
430 void ldns_rr_set_owner(ldns_rr *rr, ldns_rdf *owner);
433 * sets the question flag in the rr structure.
434 * \param[in] *rr rr to operate on
435 * \param[in] question question flag
438 void ldns_rr_set_question(ldns_rr *rr, bool question);
441 * sets the ttl in the rr structure.
442 * \param[in] *rr rr to operate on
443 * \param[in] ttl set to this ttl
446 void ldns_rr_set_ttl(ldns_rr *rr, uint32_t ttl);
449 * sets the rd_count in the rr.
450 * \param[in] *rr rr to operate on
451 * \param[in] count set to this count
454 void ldns_rr_set_rd_count(ldns_rr *rr, size_t count);
457 * sets the type in the rr.
458 * \param[in] *rr rr to operate on
459 * \param[in] rr_type set to this type
462 void ldns_rr_set_type(ldns_rr *rr, ldns_rr_type rr_type);
465 * sets the class in the rr.
466 * \param[in] *rr rr to operate on
467 * \param[in] rr_class set to this class
470 void ldns_rr_set_class(ldns_rr *rr, ldns_rr_class rr_class);
473 * sets a rdf member, it will be set on the
474 * position given. The old value is returned, like pop.
475 * \param[in] *rr the rr to operate on
476 * \param[in] *f the rdf to set
477 * \param[in] position the position the set the rdf
478 * \return the old value in the rr, NULL on failyre
480 ldns_rdf* ldns_rr_set_rdf(ldns_rr *rr, const ldns_rdf *f, size_t position);
483 * sets rd_field member, it will be
484 * placed in the next available spot.
485 * \param[in] *rr rr to operate on
486 * \param[in] *f the data field member to set
489 bool ldns_rr_push_rdf(ldns_rr *rr, const ldns_rdf *f);
492 * removes a rd_field member, it will be
493 * popped from the last position.
494 * \param[in] *rr rr to operate on
495 * \return rdf which was popped (null if nothing)
497 ldns_rdf* ldns_rr_pop_rdf(ldns_rr *rr);
500 * returns the rdata field member counter.
501 * \param[in] *rr rr to operate on
502 * \param[in] nr the number of the rdf to return
505 ldns_rdf* ldns_rr_rdf(const ldns_rr *rr, size_t nr);
508 * returns the owner name of an rr structure.
509 * \param[in] *rr rr to operate on
512 ldns_rdf* ldns_rr_owner(const ldns_rr *rr);
515 * returns the question flag of an rr structure.
516 * \param[in] *rr rr to operate on
517 * \return bool true if question
519 bool ldns_rr_is_question(const ldns_rr *rr);
522 * returns the ttl of an rr structure.
523 * \param[in] *rr the rr to read from
524 * \return the ttl of the rr
526 uint32_t ldns_rr_ttl(const ldns_rr *rr);
529 * returns the rd_count of an rr structure.
530 * \param[in] *rr the rr to read from
531 * \return the rd count of the rr
533 size_t ldns_rr_rd_count(const ldns_rr *rr);
536 * returns the type of the rr.
537 * \param[in] *rr the rr to read from
538 * \return the type of the rr
540 ldns_rr_type ldns_rr_get_type(const ldns_rr *rr);
543 * returns the class of the rr.
544 * \param[in] *rr the rr to read from
545 * \return the class of the rr
547 ldns_rr_class ldns_rr_get_class(const ldns_rr *rr);
552 * returns the number of rr's in an rr_list.
553 * \param[in] rr_list the rr_list to read from
554 * \return the number of rr's
556 size_t ldns_rr_list_rr_count(const ldns_rr_list *rr_list);
559 * sets the number of rr's in an rr_list.
560 * \param[in] rr_list the rr_list to set the count on
561 * \param[in] count the number of rr in this list
564 void ldns_rr_list_set_rr_count(ldns_rr_list *rr_list, size_t count);
567 * set a rr on a specific index in a ldns_rr_list
568 * \param[in] rr_list the rr_list to use
569 * \param[in] r the rr to set
570 * \param[in] count index into the rr_list
571 * \return the old rr which was stored in the rr_list, or
572 * NULL is the index was too large
573 * set a specific rr */
574 ldns_rr * ldns_rr_list_set_rr(ldns_rr_list *rr_list, const ldns_rr *r, size_t count);
577 * returns a specific rr of an rrlist.
578 * \param[in] rr_list the rr_list to read from
579 * \param[in] nr return this rr
580 * \return the rr at position nr
582 ldns_rr* ldns_rr_list_rr(const ldns_rr_list *rr_list, size_t nr);
585 * creates a new rr_list structure.
586 * \return a new rr_list structure
588 ldns_rr_list* ldns_rr_list_new();
591 * frees an rr_list structure.
592 * \param[in] rr_list the list to free
594 void ldns_rr_list_free(ldns_rr_list *rr_list);
597 * frees an rr_list structure and all rrs contained therein.
598 * \param[in] rr_list the list to free
600 void ldns_rr_list_deep_free(ldns_rr_list *rr_list);
603 * concatenates two ldns_rr_lists together. This modifies
604 * *left (to extend it and add the pointers from *right).
605 * \param[in] left the leftside
606 * \param[in] right the rightside
607 * \return a left with right concatenated to it
609 bool ldns_rr_list_cat(ldns_rr_list *left, ldns_rr_list *right);
612 * concatenates two ldns_rr_lists together, but makes clones of the rr's
613 * (instead of pointer copying).
614 * \param[in] left the leftside
615 * \param[in] right the rightside
616 * \return a new rr_list with leftside/rightside concatenated
618 ldns_rr_list* ldns_rr_list_cat_clone(ldns_rr_list *left, ldns_rr_list *right);
621 * pushes an rr to an rrlist.
622 * \param[in] rr_list the rr_list to push to
623 * \param[in] rr the rr to push
624 * \return false on error, otherwise true
626 bool ldns_rr_list_push_rr(ldns_rr_list *rr_list, const ldns_rr *rr);
629 * pushes an rr_list to an rrlist.
630 * \param[in] rr_list the rr_list to push to
631 * \param[in] push_list the rr_list to push
632 * \return false on error, otherwise true
634 bool ldns_rr_list_push_rr_list(ldns_rr_list *rr_list, const ldns_rr_list *push_list);
637 * pops the last rr from an rrlist.
638 * \param[in] rr_list the rr_list to pop from
639 * \return NULL if nothing to pop. Otherwise the popped RR
641 ldns_rr* ldns_rr_list_pop_rr(ldns_rr_list *rr_list);
644 * pops an rr_list of size s from an rrlist.
645 * \param[in] rr_list the rr_list to pop from
646 * \param[in] size the number of rr's to pop
647 * \return NULL if nothing to pop. Otherwise the popped rr_list
649 ldns_rr_list* ldns_rr_list_pop_rr_list(ldns_rr_list *rr_list, size_t size);
652 * returns true if the given rr is one of the rrs in the
653 * list, or if it is equal to one
654 * \param[in] rr_list the rr_list to check
655 * \param[in] rr the rr to check
656 * \return true if rr_list contains rr, false otherwise
658 bool ldns_rr_list_contains_rr(const ldns_rr_list *rr_list, ldns_rr *rr);
661 * checks if an rr_list is a rrset.
662 * \param[in] rr_list the rr_list to check
663 * \return true if it is an rrset otherwise false
665 bool ldns_is_rrset(ldns_rr_list *rr_list);
668 * pushes an rr to an rrset (which really are rr_list's).
669 * \param[in] *rr_list the rrset to push the rr to
670 * \param[in] *rr the rr to push
671 * \return true if the push succeeded otherwise false
673 bool ldns_rr_set_push_rr(ldns_rr_list *rr_list, ldns_rr *rr);
676 * pops the last rr from an rrset. This function is there only
678 * \param[in] rr_list the rr_list to pop from
679 * \return NULL if nothing to pop. Otherwise the popped RR
682 ldns_rr* ldns_rr_set_pop_rr(ldns_rr_list *rr_list);
685 * pops the first rrset from the list,
686 * the list must be sorted, so that all rr's from each rrset
687 * are next to each other
689 ldns_rr_list *ldns_rr_list_pop_rrset(ldns_rr_list *rr_list);
693 * retrieves a rrtype by looking up its name.
694 * \param[in] name a string with the name
695 * \return the type which corresponds with the name
697 ldns_rr_type ldns_get_rr_type_by_name(const char *name);
700 * retrieves a class by looking up its name.
701 * \param[in] name string with the name
702 * \return the cass which corresponds with the name
704 ldns_rr_class ldns_get_rr_class_by_name(const char *name);
707 * clones a rr and all its data
708 * \param[in] rr the rr to clone
709 * \return the new rr or NULL on failure
711 ldns_rr* ldns_rr_clone(const ldns_rr *rr);
715 * \param[in] rrlist the rrlist to clone
716 * \return the cloned rr list
718 ldns_rr_list* ldns_rr_list_clone(const ldns_rr_list *rrlist);
721 * sorts an rr_list (canonical wire format). the sorting is done inband.
722 * \param[in] unsorted the rr_list to be sorted
725 void ldns_rr_list_sort(ldns_rr_list *unsorted);
728 * compares two rrs. The TTL is not looked at.
729 * \param[in] rr1 the first one
730 * \param[in] rr2 the second one
732 * -1 if rr1 comes before rr2
733 * +1 if rr2 comes before rr1
735 int ldns_rr_compare(const ldns_rr *rr1, const ldns_rr *rr2);
738 * compares two rrs, up to the rdata.
739 * \param[in] rr1 the first one
740 * \param[in] rr2 the second one
742 * -1 if rr1 comes before rr2
743 * +1 if rr2 comes before rr1
745 int ldns_rr_compare_no_rdata(const ldns_rr *rr1, const ldns_rr *rr2);
748 * compares the wireformat of two rrs, contained in the given buffers.
749 * \param[in] rr1_buf the first one
750 * \param[in] rr2_buf the second one
752 * -1 if rr1_buf comes before rr2_buf
753 * +1 if rr2_buf comes before rr1_buf
755 int ldns_rr_compare_wire(ldns_buffer *rr1_buf, ldns_buffer *rr2_buf);
758 * returns true of the given rr's are equal.
759 * Also returns true if one record is a DS that represents the
760 * same DNSKEY record as the other record
761 * \param[in] rr1 the first rr
762 * \param[in] rr2 the second rr
763 * \return true if equal otherwise false
765 bool ldns_rr_compare_ds(const ldns_rr *rr1, const ldns_rr *rr2);
768 * compares two rr listss.
769 * \param[in] rrl1 the first one
770 * \param[in] rrl2 the second one
772 * -1 if rrl1 comes before rrl2
773 * +1 if rrl2 comes before rrl1
775 int ldns_rr_list_compare(const ldns_rr_list *rrl1, const ldns_rr_list *rrl2);
778 * calculates the uncompressed size of an RR.
779 * \param[in] r the rr to operate on
780 * \return size of the rr
782 size_t ldns_rr_uncompressed_size(const ldns_rr *r);
785 * converts each dname in a rr to its canonical form.
786 * \param[in] rr the rr to work on
789 void ldns_rr2canonical(ldns_rr *rr);
792 * converts each dname in each rr in a rr_list to its canonical form.
793 * \param[in] rr_list the rr_list to work on
796 void ldns_rr_list2canonical(ldns_rr_list *rr_list);
799 * counts the number of labels of the ownername.
800 * \param[in] rr count the labels of this rr
801 * \return the number of labels
803 uint8_t ldns_rr_label_count(ldns_rr *rr);
806 * returns the resource record descriptor for the given rr type.
808 * \param[in] type the type value of the rr type
809 *\return the ldns_rr_descriptor for this type
811 const ldns_rr_descriptor *ldns_rr_descript(uint16_t type);
814 * returns the minimum number of rdata fields of the rr type this descriptor describes.
816 * \param[in] descriptor for an rr type
817 * \return the minimum number of rdata fields
819 size_t ldns_rr_descriptor_minimum(const ldns_rr_descriptor *descriptor);
822 * returns the maximum number of rdata fields of the rr type this descriptor describes.
824 * \param[in] descriptor for an rr type
825 * \return the maximum number of rdata fields
827 size_t ldns_rr_descriptor_maximum(const ldns_rr_descriptor *descriptor);
830 * returns the rdf type for the given rdata field number of the rr type for the given descriptor.
832 * \param[in] descriptor for an rr type
833 * \param[in] field the field number
834 * \return the rdf type for the field
836 ldns_rdf_type ldns_rr_descriptor_field_type(const ldns_rr_descriptor *descriptor, size_t field);
839 * Return the rr_list which matches the rdf at position field. Think
840 * type-covered stuff for RRSIG
842 * \param[in] l the rr_list to look in
843 * \param[in] r the rdf to use for the comparison
844 * \param[in] pos at which position can we find the rdf
846 * \return a new rr list with only the RRs that match
849 ldns_rr_list *ldns_rr_list_subtype_by_rdf(ldns_rr_list *l, ldns_rdf *r, size_t pos);
852 * convert an rdf of type LDNS_RDF_TYPE_TYPE to an actual
853 * LDNS_RR_TYPE. This is usefull in the case when inspecting
854 * the rrtype covered field of an RRSIG.
855 * \param[in] rd the rdf to look at
856 * \return a ldns_rr_type with equivalent LDNS_RR_TYPE
859 ldns_rr_type ldns_rdf2rr_type(const ldns_rdf *rd);
862 * Returns the type of the first element of the RR
863 * If there are no elements present, 0 is returned
865 * \param[in] rr_list The rr list
866 * \return rr_type of the first element, or 0 if the list is empty
869 ldns_rr_list_type(const ldns_rr_list *rr_list);
872 * Returns the owner domain name rdf of the first element of the RR
873 * If there are no elements present, NULL is returned
875 * \param[in] rr_list The rr list
876 * \return dname of the first element, or NULL if the list is empty
879 ldns_rr_list_owner(const ldns_rr_list *rr_list);
885 #endif /* LDNS_RR_H */