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_NSEC3PARAM = 51,
180 LDNS_RR_TYPE_NSEC3PARAMS = 51,
182 /** draft-ietf-dnsop-trust-history */
183 LDNS_RR_TYPE_TALINK = 58,
185 LDNS_RR_TYPE_SPF = 99,
187 LDNS_RR_TYPE_UINFO = 100,
188 LDNS_RR_TYPE_UID = 101,
189 LDNS_RR_TYPE_GID = 102,
190 LDNS_RR_TYPE_UNSPEC = 103,
192 LDNS_RR_TYPE_TSIG = 250,
193 LDNS_RR_TYPE_IXFR = 251,
194 LDNS_RR_TYPE_AXFR = 252,
195 /** A request for mailbox-related records (MB, MG or MR) */
196 LDNS_RR_TYPE_MAILB = 253,
197 /** A request for mail agent RRs (Obsolete - see MX) */
198 LDNS_RR_TYPE_MAILA = 254,
199 /** any type (wildcard) */
200 LDNS_RR_TYPE_ANY = 255,
202 /* RFC 4431, 5074, DNSSEC Lookaside Validation */
203 LDNS_RR_TYPE_DLV = 32769,
205 /* type codes from nsec3 experimental phase
206 LDNS_RR_TYPE_NSEC3 = 65324,
207 LDNS_RR_TYPE_NSEC3PARAMS = 65325, */
208 LDNS_RR_TYPE_FIRST = 0,
209 LDNS_RR_TYPE_LAST = 65535,
210 LDNS_RR_TYPE_COUNT = LDNS_RR_TYPE_LAST - LDNS_RR_TYPE_FIRST + 1
212 typedef enum ldns_enum_rr_type ldns_rr_type;
217 * This is the basic DNS element that contains actual data
223 All RRs have the same top level format shown below:
226 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
227 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
232 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
234 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
236 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
239 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
241 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--|
244 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
248 NAME an owner name, i.e., the name of the node to which this
249 resource record pertains.
251 TYPE two octets containing one of the RR TYPE codes.
253 CLASS two octets containing one of the RR CLASS codes.
255 TTL a 32 bit signed integer that specifies the time interval
256 that the resource record may be cached before the source
257 of the information should again be consulted. Zero
258 values are interpreted to mean that the RR can only be
259 used for the transaction in progress, and should not be
260 cached. For example, SOA records are always distributed
261 with a zero TTL to prohibit caching. Zero values can
262 also be used for extremely volatile data.
264 RDLENGTH an unsigned 16 bit integer that specifies the length in
265 octets of the RDATA field.
267 RDATA a variable length string of octets that describes the
268 resource. The format of this information varies
269 according to the TYPE and CLASS of the resource record.
272 * The actual amount and type of rdata fields depend on the RR type of the
273 * RR, and can be found by using \ref ldns_rr_descriptor functions.
275 struct ldns_struct_rr
277 /** Owner name, uncompressed */
281 /** Number of data fields */
283 /** the type of the RR. A, MX etc. */
284 ldns_rr_type _rr_type;
285 /** Class of the resource record. */
286 ldns_rr_class _rr_class;
287 /* everything in the rdata is in network order */
288 /** The array of rdata's */
289 ldns_rdf **_rdata_fields;
290 /** question rr [it would be nicer if thous is after _rd_count]
291 ABI change: Fix this in next major release
295 typedef struct ldns_struct_rr ldns_rr;
298 * List or Set of Resource Records
300 * Contains a list of rr's <br>
301 * No official RFC-like checks are made
303 struct ldns_struct_rr_list
309 typedef struct ldns_struct_rr_list ldns_rr_list;
312 * Contains all information about resource record types.
314 * This structure contains, for all rr types, the rdata fields that are defined.
316 struct ldns_struct_rr_descriptor
318 /** Type of the RR that is described here */
320 /** Textual name of the RR type. */
322 /** Minimum number of rdata fields in the RRs of this type. */
324 /** Maximum number of rdata fields in the RRs of this type. */
326 /** Wireformat specification for the rr, i.e. the types of rdata fields in their respective order. */
327 const ldns_rdf_type *_wireformat;
328 /** Special rdf types */
329 ldns_rdf_type _variable;
330 /** Specifies whether compression can be used for dnames in this RR type. */
331 ldns_rr_compress _compress;
332 /** The number of DNAMEs in the _wireformat string, for parsing. */
333 uint8_t _dname_count;
335 typedef struct ldns_struct_rr_descriptor ldns_rr_descriptor;
338 * creates a new rr structure.
341 ldns_rr* ldns_rr_new(void);
344 * creates a new rr structure, based on the given type.
345 * alloc enough space to hold all the rdf's
347 ldns_rr* ldns_rr_new_frm_type(ldns_rr_type t);
350 * frees an RR structure
351 * \param[in] *rr the RR to be freed
354 void ldns_rr_free(ldns_rr *rr);
357 * creates an rr from a string.
358 * The string should be a fully filled-in rr, like
359 * ownername <space> TTL <space> CLASS <space>
360 * TYPE <space> RDATA.
361 * \param[out] n the rr to return
362 * \param[in] str the string to convert
363 * \param[in] default_ttl default ttl value for the rr.
364 * If 0 DEF_TTL will be used
365 * \param[in] origin when the owner is relative add this.
366 * The caller must ldns_rdf_deep_free it.
367 * \param[out] prev the previous ownername. if this value is not NULL,
368 * the function overwrites this with the ownername found in this
369 * string. The caller must then ldns_rdf_deep_free it.
370 * \return a status msg describing an error or LDNS_STATUS_OK
372 ldns_status ldns_rr_new_frm_str(ldns_rr **n, const char *str,
373 uint32_t default_ttl, ldns_rdf *origin,
377 * creates an rr for the question section from a string, i.e.
378 * without RDATA fields
379 * Origin and previous RR functionality are the same as in
380 * ldns_rr_new_frm_str()
381 * \param[out] n the rr to return
382 * \param[in] str the string to convert
383 * \param[in] origin when the owner is relative add this.
384 * The caller must ldns_rdf_deep_free it.
385 * \param prev the previous ownername. the function overwrite this with
386 * the current found ownername. The caller must ldns_rdf_deep_free it.
387 * \return a status msg describing an error or LDNS_STATUS_OK
389 ldns_status ldns_rr_new_question_frm_str(ldns_rr **n, const char *str,
390 ldns_rdf *origin, ldns_rdf **prev);
393 * creates a new rr from a file containing a string.
394 * \param[out] rr the new rr
395 * \param[in] fp the file pointer to use
396 * \param[in] default_ttl pointer to a default ttl for the rr. If NULL DEF_TTL will be used
397 * the pointer will be updated if the file contains a $TTL directive
398 * \param[in] origin when the owner is relative add this
399 * the pointer will be updated if the file contains a $ORIGIN directive
400 * The caller must ldns_rdf_deep_free it.
401 * \param[in] prev when the owner is whitespaces use this as the * ownername
402 * the pointer will be updated after the call
403 * The caller must ldns_rdf_deep_free it.
404 * \return a ldns_status with an error or LDNS_STATUS_OK
406 ldns_status ldns_rr_new_frm_fp(ldns_rr **rr, FILE *fp, uint32_t *default_ttl, ldns_rdf **origin, ldns_rdf **prev);
409 * creates a new rr from a file containing a string.
410 * \param[out] rr the new rr
411 * \param[in] fp the file pointer to use
412 * \param[in] default_ttl a default ttl for the rr. If NULL DEF_TTL will be used
413 * the pointer will be updated if the file contains a $TTL directive
414 * \param[in] origin when the owner is relative add this
415 * the pointer will be updated if the file contains a $ORIGIN directive
416 * The caller must ldns_rdf_deep_free it.
417 * \param[in] line_nr pointer to an integer containing the current line number (for debugging purposes)
418 * \param[in] prev when the owner is whitespaces use this as the * ownername
419 * the pointer will be updated after the call
420 * The caller must ldns_rdf_deep_free it.
421 * \return a ldns_status with an error or LDNS_STATUS_OK
423 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);
426 * sets the owner in the rr structure.
427 * \param[in] *rr rr to operate on
428 * \param[in] *owner set to this owner
431 void ldns_rr_set_owner(ldns_rr *rr, ldns_rdf *owner);
434 * sets the question flag in the rr structure.
435 * \param[in] *rr rr to operate on
436 * \param[in] question question flag
439 void ldns_rr_set_question(ldns_rr *rr, bool question);
442 * sets the ttl in the rr structure.
443 * \param[in] *rr rr to operate on
444 * \param[in] ttl set to this ttl
447 void ldns_rr_set_ttl(ldns_rr *rr, uint32_t ttl);
450 * sets the rd_count in the rr.
451 * \param[in] *rr rr to operate on
452 * \param[in] count set to this count
455 void ldns_rr_set_rd_count(ldns_rr *rr, size_t count);
458 * sets the type in the rr.
459 * \param[in] *rr rr to operate on
460 * \param[in] rr_type set to this type
463 void ldns_rr_set_type(ldns_rr *rr, ldns_rr_type rr_type);
466 * sets the class in the rr.
467 * \param[in] *rr rr to operate on
468 * \param[in] rr_class set to this class
471 void ldns_rr_set_class(ldns_rr *rr, ldns_rr_class rr_class);
474 * sets a rdf member, it will be set on the
475 * position given. The old value is returned, like pop.
476 * \param[in] *rr the rr to operate on
477 * \param[in] *f the rdf to set
478 * \param[in] position the position the set the rdf
479 * \return the old value in the rr, NULL on failyre
481 ldns_rdf* ldns_rr_set_rdf(ldns_rr *rr, const ldns_rdf *f, size_t position);
484 * sets rd_field member, it will be
485 * placed in the next available spot.
486 * \param[in] *rr rr to operate on
487 * \param[in] *f the data field member to set
490 bool ldns_rr_push_rdf(ldns_rr *rr, const ldns_rdf *f);
493 * removes a rd_field member, it will be
494 * popped from the last position.
495 * \param[in] *rr rr to operate on
496 * \return rdf which was popped (null if nothing)
498 ldns_rdf* ldns_rr_pop_rdf(ldns_rr *rr);
501 * returns the rdata field member counter.
502 * \param[in] *rr rr to operate on
503 * \param[in] nr the number of the rdf to return
506 ldns_rdf* ldns_rr_rdf(const ldns_rr *rr, size_t nr);
509 * returns the owner name of an rr structure.
510 * \param[in] *rr rr to operate on
513 ldns_rdf* ldns_rr_owner(const ldns_rr *rr);
516 * returns the question flag of an rr structure.
517 * \param[in] *rr rr to operate on
518 * \return bool true if question
520 bool ldns_rr_is_question(const ldns_rr *rr);
523 * returns the ttl of an rr structure.
524 * \param[in] *rr the rr to read from
525 * \return the ttl of the rr
527 uint32_t ldns_rr_ttl(const ldns_rr *rr);
530 * returns the rd_count of an rr structure.
531 * \param[in] *rr the rr to read from
532 * \return the rd count of the rr
534 size_t ldns_rr_rd_count(const ldns_rr *rr);
537 * returns the type of the rr.
538 * \param[in] *rr the rr to read from
539 * \return the type of the rr
541 ldns_rr_type ldns_rr_get_type(const ldns_rr *rr);
544 * returns the class of the rr.
545 * \param[in] *rr the rr to read from
546 * \return the class of the rr
548 ldns_rr_class ldns_rr_get_class(const ldns_rr *rr);
553 * returns the number of rr's in an rr_list.
554 * \param[in] rr_list the rr_list to read from
555 * \return the number of rr's
557 size_t ldns_rr_list_rr_count(const ldns_rr_list *rr_list);
560 * sets the number of rr's in an rr_list.
561 * \param[in] rr_list the rr_list to set the count on
562 * \param[in] count the number of rr in this list
565 void ldns_rr_list_set_rr_count(ldns_rr_list *rr_list, size_t count);
568 * set a rr on a specific index in a ldns_rr_list
569 * \param[in] rr_list the rr_list to use
570 * \param[in] r the rr to set
571 * \param[in] count index into the rr_list
572 * \return the old rr which was stored in the rr_list, or
573 * NULL is the index was too large
574 * set a specific rr */
575 ldns_rr * ldns_rr_list_set_rr(ldns_rr_list *rr_list, const ldns_rr *r, size_t count);
578 * returns a specific rr of an rrlist.
579 * \param[in] rr_list the rr_list to read from
580 * \param[in] nr return this rr
581 * \return the rr at position nr
583 ldns_rr* ldns_rr_list_rr(const ldns_rr_list *rr_list, size_t nr);
586 * creates a new rr_list structure.
587 * \return a new rr_list structure
589 ldns_rr_list* ldns_rr_list_new();
592 * frees an rr_list structure.
593 * \param[in] rr_list the list to free
595 void ldns_rr_list_free(ldns_rr_list *rr_list);
598 * frees an rr_list structure and all rrs contained therein.
599 * \param[in] rr_list the list to free
601 void ldns_rr_list_deep_free(ldns_rr_list *rr_list);
604 * concatenates two ldns_rr_lists together. This modifies
605 * *left (to extend it and add the pointers from *right).
606 * \param[in] left the leftside
607 * \param[in] right the rightside
608 * \return a left with right concatenated to it
610 bool ldns_rr_list_cat(ldns_rr_list *left, ldns_rr_list *right);
613 * concatenates two ldns_rr_lists together, but makes clones of the rr's
614 * (instead of pointer copying).
615 * \param[in] left the leftside
616 * \param[in] right the rightside
617 * \return a new rr_list with leftside/rightside concatenated
619 ldns_rr_list* ldns_rr_list_cat_clone(ldns_rr_list *left, ldns_rr_list *right);
622 * pushes an rr to an rrlist.
623 * \param[in] rr_list the rr_list to push to
624 * \param[in] rr the rr to push
625 * \return false on error, otherwise true
627 bool ldns_rr_list_push_rr(ldns_rr_list *rr_list, const ldns_rr *rr);
630 * pushes an rr_list to an rrlist.
631 * \param[in] rr_list the rr_list to push to
632 * \param[in] push_list the rr_list to push
633 * \return false on error, otherwise true
635 bool ldns_rr_list_push_rr_list(ldns_rr_list *rr_list, const ldns_rr_list *push_list);
638 * pops the last rr from an rrlist.
639 * \param[in] rr_list the rr_list to pop from
640 * \return NULL if nothing to pop. Otherwise the popped RR
642 ldns_rr* ldns_rr_list_pop_rr(ldns_rr_list *rr_list);
645 * pops an rr_list of size s from an rrlist.
646 * \param[in] rr_list the rr_list to pop from
647 * \param[in] size the number of rr's to pop
648 * \return NULL if nothing to pop. Otherwise the popped rr_list
650 ldns_rr_list* ldns_rr_list_pop_rr_list(ldns_rr_list *rr_list, size_t size);
653 * returns true if the given rr is one of the rrs in the
654 * list, or if it is equal to one
655 * \param[in] rr_list the rr_list to check
656 * \param[in] rr the rr to check
657 * \return true if rr_list contains rr, false otherwise
659 bool ldns_rr_list_contains_rr(const ldns_rr_list *rr_list, ldns_rr *rr);
662 * checks if an rr_list is a rrset.
663 * \param[in] rr_list the rr_list to check
664 * \return true if it is an rrset otherwise false
666 bool ldns_is_rrset(ldns_rr_list *rr_list);
669 * pushes an rr to an rrset (which really are rr_list's).
670 * \param[in] *rr_list the rrset to push the rr to
671 * \param[in] *rr the rr to push
672 * \return true if the push succeeded otherwise false
674 bool ldns_rr_set_push_rr(ldns_rr_list *rr_list, ldns_rr *rr);
677 * pops the last rr from an rrset. This function is there only
679 * \param[in] rr_list the rr_list to pop from
680 * \return NULL if nothing to pop. Otherwise the popped RR
683 ldns_rr* ldns_rr_set_pop_rr(ldns_rr_list *rr_list);
686 * pops the first rrset from the list,
687 * the list must be sorted, so that all rr's from each rrset
688 * are next to each other
690 ldns_rr_list *ldns_rr_list_pop_rrset(ldns_rr_list *rr_list);
694 * retrieves a rrtype by looking up its name.
695 * \param[in] name a string with the name
696 * \return the type which corresponds with the name
698 ldns_rr_type ldns_get_rr_type_by_name(const char *name);
701 * retrieves a class by looking up its name.
702 * \param[in] name string with the name
703 * \return the cass which corresponds with the name
705 ldns_rr_class ldns_get_rr_class_by_name(const char *name);
708 * clones a rr and all its data
709 * \param[in] rr the rr to clone
710 * \return the new rr or NULL on failure
712 ldns_rr* ldns_rr_clone(const ldns_rr *rr);
716 * \param[in] rrlist the rrlist to clone
717 * \return the cloned rr list
719 ldns_rr_list* ldns_rr_list_clone(const ldns_rr_list *rrlist);
722 * sorts an rr_list (canonical wire format). the sorting is done inband.
723 * \param[in] unsorted the rr_list to be sorted
726 void ldns_rr_list_sort(ldns_rr_list *unsorted);
729 * compares two rrs. The TTL is not looked at.
730 * \param[in] rr1 the first one
731 * \param[in] rr2 the second one
733 * -1 if rr1 comes before rr2
734 * +1 if rr2 comes before rr1
736 int ldns_rr_compare(const ldns_rr *rr1, const ldns_rr *rr2);
739 * compares two rrs, up to the rdata.
740 * \param[in] rr1 the first one
741 * \param[in] rr2 the second one
743 * -1 if rr1 comes before rr2
744 * +1 if rr2 comes before rr1
746 int ldns_rr_compare_no_rdata(const ldns_rr *rr1, const ldns_rr *rr2);
749 * compares the wireformat of two rrs, contained in the given buffers.
750 * \param[in] rr1_buf the first one
751 * \param[in] rr2_buf the second one
753 * -1 if rr1_buf comes before rr2_buf
754 * +1 if rr2_buf comes before rr1_buf
756 int ldns_rr_compare_wire(ldns_buffer *rr1_buf, ldns_buffer *rr2_buf);
759 * returns true of the given rr's are equal.
760 * Also returns true if one record is a DS that represents the
761 * same DNSKEY record as the other record
762 * \param[in] rr1 the first rr
763 * \param[in] rr2 the second rr
764 * \return true if equal otherwise false
766 bool ldns_rr_compare_ds(const ldns_rr *rr1, const ldns_rr *rr2);
769 * compares two rr listss.
770 * \param[in] rrl1 the first one
771 * \param[in] rrl2 the second one
773 * -1 if rrl1 comes before rrl2
774 * +1 if rrl2 comes before rrl1
776 int ldns_rr_list_compare(const ldns_rr_list *rrl1, const ldns_rr_list *rrl2);
779 * calculates the uncompressed size of an RR.
780 * \param[in] r the rr to operate on
781 * \return size of the rr
783 size_t ldns_rr_uncompressed_size(const ldns_rr *r);
786 * converts each dname in a rr to its canonical form.
787 * \param[in] rr the rr to work on
790 void ldns_rr2canonical(ldns_rr *rr);
793 * converts each dname in each rr in a rr_list to its canonical form.
794 * \param[in] rr_list the rr_list to work on
797 void ldns_rr_list2canonical(ldns_rr_list *rr_list);
800 * counts the number of labels of the ownername.
801 * \param[in] rr count the labels of this rr
802 * \return the number of labels
804 uint8_t ldns_rr_label_count(ldns_rr *rr);
807 * returns the resource record descriptor for the given rr type.
809 * \param[in] type the type value of the rr type
810 *\return the ldns_rr_descriptor for this type
812 const ldns_rr_descriptor *ldns_rr_descript(uint16_t type);
815 * returns the minimum number of rdata fields of the rr type this descriptor describes.
817 * \param[in] descriptor for an rr type
818 * \return the minimum number of rdata fields
820 size_t ldns_rr_descriptor_minimum(const ldns_rr_descriptor *descriptor);
823 * returns the maximum number of rdata fields of the rr type this descriptor describes.
825 * \param[in] descriptor for an rr type
826 * \return the maximum number of rdata fields
828 size_t ldns_rr_descriptor_maximum(const ldns_rr_descriptor *descriptor);
831 * returns the rdf type for the given rdata field number of the rr type for the given descriptor.
833 * \param[in] descriptor for an rr type
834 * \param[in] field the field number
835 * \return the rdf type for the field
837 ldns_rdf_type ldns_rr_descriptor_field_type(const ldns_rr_descriptor *descriptor, size_t field);
840 * Return the rr_list which matches the rdf at position field. Think
841 * type-covered stuff for RRSIG
843 * \param[in] l the rr_list to look in
844 * \param[in] r the rdf to use for the comparison
845 * \param[in] pos at which position can we find the rdf
847 * \return a new rr list with only the RRs that match
850 ldns_rr_list *ldns_rr_list_subtype_by_rdf(ldns_rr_list *l, ldns_rdf *r, size_t pos);
853 * convert an rdf of type LDNS_RDF_TYPE_TYPE to an actual
854 * LDNS_RR_TYPE. This is usefull in the case when inspecting
855 * the rrtype covered field of an RRSIG.
856 * \param[in] rd the rdf to look at
857 * \return a ldns_rr_type with equivalent LDNS_RR_TYPE
860 ldns_rr_type ldns_rdf2rr_type(const ldns_rdf *rd);
863 * Returns the type of the first element of the RR
864 * If there are no elements present, 0 is returned
866 * \param[in] rr_list The rr list
867 * \return rr_type of the first element, or 0 if the list is empty
870 ldns_rr_list_type(const ldns_rr_list *rr_list);
873 * Returns the owner domain name rdf of the first element of the RR
874 * If there are no elements present, NULL is returned
876 * \param[in] rr_list The rr list
877 * \return dname of the first element, or NULL if the list is empty
880 ldns_rr_list_owner(const ldns_rr_list *rr_list);
886 #endif /* LDNS_RR_H */