/*
* rrdef.h
*
* RR definitions
*
* a Net::DNS like library for C
*
* (c) NLnet Labs, 2005-2006
*
* See the file LICENSE for the license
*/

/**
* \file
*
* Defines resource record types and constants.
*/

#ifndef LDNS_RRDEF_H
#define LDNS_RRDEF_H

#ifdef __cplusplus
extern "C" {
#endif

/** Maximum length of a dname label */
#define LDNS_MAX_LABELLEN     63
/** Maximum length of a complete dname */
#define LDNS_MAX_DOMAINLEN    255
/** Maximum number of pointers in 1 dname */
#define LDNS_MAX_POINTERS       65535
/** The bytes TTL, CLASS and length use up in an rr */
#define LDNS_RR_OVERHEAD        10

#define LDNS_DNSSEC_KEYPROTO    3
#define LDNS_KEY_ZONE_KEY   0x0100 /* set for ZSK&KSK, rfc 4034 */
#define LDNS_KEY_SEP_KEY    0x0001 /* set for KSK, rfc 4034 */
#define LDNS_KEY_REVOKE_KEY 0x0080 /* used to revoke KSK, rfc 5011 */

/* The first fields are contiguous and can be referenced instantly */
#define LDNS_RDATA_FIELD_DESCRIPTORS_COMMON 259

/** lookuptable for rr classes  */
extern struct sldns_struct_lookup_table* sldns_rr_classes;

/**
*  The different RR classes.
*/
enum sldns_enum_rr_class
{
       /** the Internet */
       LDNS_RR_CLASS_IN        = 1,
       /** Chaos class */
       LDNS_RR_CLASS_CH        = 3,
       /** Hesiod (Dyer 87) */
       LDNS_RR_CLASS_HS        = 4,
       /** None class, dynamic update */
       LDNS_RR_CLASS_NONE      = 254,
       /** Any class */
       LDNS_RR_CLASS_ANY       = 255,

       LDNS_RR_CLASS_FIRST     = 0,
       LDNS_RR_CLASS_LAST      = 65535,
       LDNS_RR_CLASS_COUNT     = LDNS_RR_CLASS_LAST - LDNS_RR_CLASS_FIRST + 1
};
typedef enum sldns_enum_rr_class sldns_rr_class;

/**
*  Used to specify whether compression is allowed.
*/
enum sldns_enum_rr_compress
{
       /** compression is allowed */
       LDNS_RR_COMPRESS,
       LDNS_RR_NO_COMPRESS
};
typedef enum sldns_enum_rr_compress sldns_rr_compress;

/**
* The different RR types.
*/
enum sldns_enum_rr_type
{
       /**  a host address */
       LDNS_RR_TYPE_A = 1,
       /**  an authoritative name server */
       LDNS_RR_TYPE_NS = 2,
       /**  a mail destination (Obsolete - use MX) */
       LDNS_RR_TYPE_MD = 3,
       /**  a mail forwarder (Obsolete - use MX) */
       LDNS_RR_TYPE_MF = 4,
       /**  the canonical name for an alias */
       LDNS_RR_TYPE_CNAME = 5,
       /**  marks the start of a zone of authority */
       LDNS_RR_TYPE_SOA = 6,
       /**  a mailbox domain name (EXPERIMENTAL) */
       LDNS_RR_TYPE_MB = 7,
       /**  a mail group member (EXPERIMENTAL) */
       LDNS_RR_TYPE_MG = 8,
       /**  a mail rename domain name (EXPERIMENTAL) */
       LDNS_RR_TYPE_MR = 9,
       /**  a null RR (EXPERIMENTAL) */
       LDNS_RR_TYPE_NULL = 10,
       /**  a well known service description */
       LDNS_RR_TYPE_WKS = 11,
       /**  a domain name pointer */
       LDNS_RR_TYPE_PTR = 12,
       /**  host information */
       LDNS_RR_TYPE_HINFO = 13,
       /**  mailbox or mail list information */
       LDNS_RR_TYPE_MINFO = 14,
       /**  mail exchange */
       LDNS_RR_TYPE_MX = 15,
       /**  text strings */
       LDNS_RR_TYPE_TXT = 16,
       /**  RFC1183 */
       LDNS_RR_TYPE_RP = 17,
       /**  RFC1183 */
       LDNS_RR_TYPE_AFSDB = 18,
       /**  RFC1183 */
       LDNS_RR_TYPE_X25 = 19,
       /**  RFC1183 */
       LDNS_RR_TYPE_ISDN = 20,
       /**  RFC1183 */
       LDNS_RR_TYPE_RT = 21,
       /**  RFC1706 */
       LDNS_RR_TYPE_NSAP = 22,
       /**  RFC1348 */
       LDNS_RR_TYPE_NSAP_PTR = 23,
       /**  2535typecode */
       LDNS_RR_TYPE_SIG = 24,
       /**  2535typecode */
       LDNS_RR_TYPE_KEY = 25,
       /**  RFC2163 */
       LDNS_RR_TYPE_PX = 26,
       /**  RFC1712 */
       LDNS_RR_TYPE_GPOS = 27,
       /**  ipv6 address */
       LDNS_RR_TYPE_AAAA = 28,
       /**  LOC record  RFC1876 */
       LDNS_RR_TYPE_LOC = 29,
       /**  2535typecode */
       LDNS_RR_TYPE_NXT = 30,
       /**  draft-ietf-nimrod-dns-01.txt */
       LDNS_RR_TYPE_EID = 31,
       /**  draft-ietf-nimrod-dns-01.txt */
       LDNS_RR_TYPE_NIMLOC = 32,
       /**  SRV record RFC2782 */
       LDNS_RR_TYPE_SRV = 33,
       /**  http://www.jhsoft.com/rfc/af-saa-0069.000.rtf */
       LDNS_RR_TYPE_ATMA = 34,
       /**  RFC2915 */
       LDNS_RR_TYPE_NAPTR = 35,
       /**  RFC2230 */
       LDNS_RR_TYPE_KX = 36,
       /**  RFC2538 */
       LDNS_RR_TYPE_CERT = 37,
       /**  RFC2874 */
       LDNS_RR_TYPE_A6 = 38,
       /**  RFC2672 */
       LDNS_RR_TYPE_DNAME = 39,
       /**  dnsind-kitchen-sink-02.txt */
       LDNS_RR_TYPE_SINK = 40,
       /**  Pseudo OPT record... */
       LDNS_RR_TYPE_OPT = 41,
       /**  RFC3123 */
       LDNS_RR_TYPE_APL = 42,
       /**  RFC4034, RFC3658 */
       LDNS_RR_TYPE_DS = 43,
       /**  SSH Key Fingerprint */
       LDNS_RR_TYPE_SSHFP = 44, /* RFC 4255 */
       /**  IPsec Key */
       LDNS_RR_TYPE_IPSECKEY = 45, /* RFC 4025 */
       /**  DNSSEC */
       LDNS_RR_TYPE_RRSIG = 46, /* RFC 4034 */
       LDNS_RR_TYPE_NSEC = 47, /* RFC 4034 */
       LDNS_RR_TYPE_DNSKEY = 48, /* RFC 4034 */

       LDNS_RR_TYPE_DHCID = 49, /* RFC 4701 */
       /* NSEC3 */
       LDNS_RR_TYPE_NSEC3 = 50, /* RFC 5155 */
       LDNS_RR_TYPE_NSEC3PARAM = 51, /* RFC 5155 */
       LDNS_RR_TYPE_NSEC3PARAMS = 51,
       LDNS_RR_TYPE_TLSA = 52, /* RFC 6698 */
       LDNS_RR_TYPE_SMIMEA = 53, /* RFC 8162 */
       LDNS_RR_TYPE_HIP = 55, /* RFC 5205 */

       /** draft-reid-dnsext-zs */
       LDNS_RR_TYPE_NINFO = 56,
       /** draft-reid-dnsext-rkey */
       LDNS_RR_TYPE_RKEY = 57,
       /** draft-ietf-dnsop-trust-history */
       LDNS_RR_TYPE_TALINK = 58,
       LDNS_RR_TYPE_CDS = 59, /** RFC 7344 */
       LDNS_RR_TYPE_CDNSKEY = 60, /** RFC 7344 */
       LDNS_RR_TYPE_OPENPGPKEY = 61, /* RFC 7929 */
       LDNS_RR_TYPE_CSYNC = 62, /* RFC 7477 */
       LDNS_RR_TYPE_ZONEMD = 63, /* draft-ietf-dnsop-dns-zone-digest-12 */
       LDNS_RR_TYPE_SVCB = 64, /* draft-ietf-dnsop-svcb-https-04 */
       LDNS_RR_TYPE_HTTPS = 65, /* draft-ietf-dnsop-svcb-https-04 */

       LDNS_RR_TYPE_SPF = 99, /* RFC 4408 */

       LDNS_RR_TYPE_UINFO = 100,
       LDNS_RR_TYPE_UID = 101,
       LDNS_RR_TYPE_GID = 102,
       LDNS_RR_TYPE_UNSPEC = 103,

       LDNS_RR_TYPE_NID = 104, /* RFC 6742 */
       LDNS_RR_TYPE_L32 = 105, /* RFC 6742 */
       LDNS_RR_TYPE_L64 = 106, /* RFC 6742 */
       LDNS_RR_TYPE_LP = 107, /* RFC 6742 */

       /** draft-jabley-dnsext-eui48-eui64-rrtypes */
       LDNS_RR_TYPE_EUI48 = 108,
       LDNS_RR_TYPE_EUI64 = 109,

       LDNS_RR_TYPE_TKEY = 249, /* RFC 2930 */
       LDNS_RR_TYPE_TSIG = 250,
       LDNS_RR_TYPE_IXFR = 251,
       LDNS_RR_TYPE_AXFR = 252,
       /**  A request for mailbox-related records (MB, MG or MR) */
       LDNS_RR_TYPE_MAILB = 253,
       /**  A request for mail agent RRs (Obsolete - see MX) */
       LDNS_RR_TYPE_MAILA = 254,
       /**  any type (wildcard) */
       LDNS_RR_TYPE_ANY = 255,
       LDNS_RR_TYPE_URI = 256, /* RFC 7553 */
       LDNS_RR_TYPE_CAA = 257, /* RFC 6844 */
       LDNS_RR_TYPE_AVC = 258,

       LDNS_RR_TYPE_RESINFO = 261, /* RFC 9606 */

       /** DNSSEC Trust Authorities */
       LDNS_RR_TYPE_TA = 32768,
       /* RFC 4431, 5074, DNSSEC Lookaside Validation */
       LDNS_RR_TYPE_DLV = 32769,

       /* type codes from nsec3 experimental phase
       LDNS_RR_TYPE_NSEC3 = 65324,
       LDNS_RR_TYPE_NSEC3PARAMS = 65325, */
       LDNS_RR_TYPE_FIRST = 0,
       LDNS_RR_TYPE_LAST  = 65535,
       LDNS_RR_TYPE_COUNT = LDNS_RR_TYPE_LAST - LDNS_RR_TYPE_FIRST + 1
};
typedef enum sldns_enum_rr_type sldns_rr_type;

/* RDATA */
#define LDNS_MAX_RDFLEN 65535

#define LDNS_RDF_SIZE_BYTE              1
#define LDNS_RDF_SIZE_WORD              2
#define LDNS_RDF_SIZE_DOUBLEWORD        4
#define LDNS_RDF_SIZE_6BYTES            6
#define LDNS_RDF_SIZE_8BYTES            8
#define LDNS_RDF_SIZE_16BYTES           16

#define LDNS_NSEC3_VARS_OPTOUT_MASK 0x01

#define LDNS_APL_IP4            1
#define LDNS_APL_IP6            2
#define LDNS_APL_MASK           0x7f
#define LDNS_APL_NEGATION       0x80

/**
* The different types of RDATA fields.
*/
enum sldns_enum_rdf_type
{
       /** none */
       LDNS_RDF_TYPE_NONE,
       /** domain name */
       LDNS_RDF_TYPE_DNAME,
       /** 8 bits */
       LDNS_RDF_TYPE_INT8,
       /** 16 bits */
       LDNS_RDF_TYPE_INT16,
       /** 32 bits */
       LDNS_RDF_TYPE_INT32,
       /** A record */
       LDNS_RDF_TYPE_A,
       /** AAAA record */
       LDNS_RDF_TYPE_AAAA,
       /** txt string */
       LDNS_RDF_TYPE_STR,
       /** apl data */
       LDNS_RDF_TYPE_APL,
       /** b32 string */
       LDNS_RDF_TYPE_B32_EXT,
       /** b64 string */
       LDNS_RDF_TYPE_B64,
       /** hex string */
       LDNS_RDF_TYPE_HEX,
       /** nsec type codes */
       LDNS_RDF_TYPE_NSEC,
       /** a RR type */
       LDNS_RDF_TYPE_TYPE,
       /** a class */
       LDNS_RDF_TYPE_CLASS,
       /** certificate algorithm */
       LDNS_RDF_TYPE_CERT_ALG,
       /** a key algorithm */
       LDNS_RDF_TYPE_ALG,
       /** unknown types */
       LDNS_RDF_TYPE_UNKNOWN,
       /** time (32 bits) */
       LDNS_RDF_TYPE_TIME,
       /** period */
       LDNS_RDF_TYPE_PERIOD,
       /** tsig time 48 bits */
       LDNS_RDF_TYPE_TSIGTIME,
       /** Represents the Public Key Algorithm, HIT and Public Key fields
           for the HIP RR types.  A HIP specific rdf type is used because of
           the unusual layout in wireformat (see RFC 5205 Section 5) */
       LDNS_RDF_TYPE_HIP,
       /** variable length any type rdata where the length
           is specified by the first 2 bytes */
       LDNS_RDF_TYPE_INT16_DATA,
       /** protocol and port bitmaps */
       LDNS_RDF_TYPE_SERVICE,
       /** location data */
       LDNS_RDF_TYPE_LOC,
       /** well known services */
       LDNS_RDF_TYPE_WKS,
       /** NSAP */
       LDNS_RDF_TYPE_NSAP,
       /** ATMA */
       LDNS_RDF_TYPE_ATMA,
       /** IPSECKEY */
       LDNS_RDF_TYPE_IPSECKEY,
       /** nsec3 hash salt */
       LDNS_RDF_TYPE_NSEC3_SALT,
       /** nsec3 base32 string (with length byte on wire */
       LDNS_RDF_TYPE_NSEC3_NEXT_OWNER,

       /** 4 shorts represented as 4 * 16 bit hex numbers
        *  separated by colons. For NID and L64.
        */
       LDNS_RDF_TYPE_ILNP64,

       /** 6 * 8 bit hex numbers separated by dashes. For EUI48. */
       LDNS_RDF_TYPE_EUI48,
       /** 8 * 8 bit hex numbers separated by dashes. For EUI64. */
       LDNS_RDF_TYPE_EUI64,

       /** Character string without quotes. */
       LDNS_RDF_TYPE_UNQUOTED,

       /** A non-zero sequence of US-ASCII letters and numbers in lower case.
        *  For CAA.
        */
       LDNS_RDF_TYPE_TAG,

       /** A <character-string> encoding of the value field as specified
        * [RFC1035], Section 5.1., encoded as remaining rdata.
        * For CAA, URI.
        */
       LDNS_RDF_TYPE_LONG_STR,

       /** TSIG extended 16bit error value */
       LDNS_RDF_TYPE_TSIGERROR,

       /* draft-ietf-dnsop-svcb-https-05:
        * each SvcParam consisting of a SvcParamKey=SvcParamValue pair or
        * a standalone SvcParamKey */
       LDNS_RDF_TYPE_SVCPARAM,

       /* Aliases */
       LDNS_RDF_TYPE_BITMAP = LDNS_RDF_TYPE_NSEC,
};
typedef enum sldns_enum_rdf_type sldns_rdf_type;

/**
* Algorithms used in dns
*/
enum sldns_enum_algorithm
{
       LDNS_RSAMD5             = 1,   /* RFC 4034,4035 */
       LDNS_DH                 = 2,
       LDNS_DSA                = 3,
       LDNS_ECC                = 4,
       LDNS_RSASHA1            = 5,
       LDNS_DSA_NSEC3          = 6,
       LDNS_RSASHA1_NSEC3      = 7,
       LDNS_RSASHA256          = 8,   /* RFC 5702 */
       LDNS_RSASHA512          = 10,  /* RFC 5702 */
       LDNS_ECC_GOST           = 12,  /* RFC 5933 */
       LDNS_ECDSAP256SHA256    = 13,  /* RFC 6605 */
       LDNS_ECDSAP384SHA384    = 14,  /* RFC 6605 */
       LDNS_ED25519            = 15,  /* RFC 8080 */
       LDNS_ED448              = 16,  /* RFC 8080 */
       LDNS_INDIRECT           = 252,
       LDNS_PRIVATEDNS         = 253,
       LDNS_PRIVATEOID         = 254
};
typedef enum sldns_enum_algorithm sldns_algorithm;

/**
* Hashing algorithms used in the DS record
*/
enum sldns_enum_hash
{
       LDNS_SHA1               = 1,  /* RFC 4034 */
       LDNS_SHA256             = 2,  /* RFC 4509 */
       LDNS_HASH_GOST          = 3,  /* RFC 5933 */
       LDNS_SHA384             = 4   /* RFC 6605 */
};
typedef enum sldns_enum_hash sldns_hash;

/**
* algorithms used in CERT rrs
*/
enum sldns_enum_cert_algorithm
{
       LDNS_CERT_PKIX          = 1,
       LDNS_CERT_SPKI          = 2,
       LDNS_CERT_PGP           = 3,
       LDNS_CERT_IPKIX         = 4,
       LDNS_CERT_ISPKI         = 5,
       LDNS_CERT_IPGP          = 6,
       LDNS_CERT_ACPKIX        = 7,
       LDNS_CERT_IACPKIX       = 8,
       LDNS_CERT_URI           = 253,
       LDNS_CERT_OID           = 254
};
typedef enum sldns_enum_cert_algorithm sldns_cert_algorithm;

/**
* EDNS option codes
*/
enum sldns_enum_edns_option
{
       LDNS_EDNS_LLQ = 1, /* http://files.dns-sd.org/draft-sekar-dns-llq.txt */
       LDNS_EDNS_UL = 2, /* http://files.dns-sd.org/draft-sekar-dns-ul.txt */
       LDNS_EDNS_NSID = 3, /* RFC5001 */
       /* 4 draft-cheshire-edns0-owner-option */
       LDNS_EDNS_DAU = 5, /* RFC6975 */
       LDNS_EDNS_DHU = 6, /* RFC6975 */
       LDNS_EDNS_N3U = 7, /* RFC6975 */
       LDNS_EDNS_CLIENT_SUBNET = 8, /* RFC7871 */
       LDNS_EDNS_COOKIE = 10, /* RFC7873 */
       LDNS_EDNS_KEEPALIVE = 11, /* draft-ietf-dnsop-edns-tcp-keepalive*/
       LDNS_EDNS_PADDING = 12, /* RFC7830 */
       LDNS_EDNS_EDE = 15, /* RFC8914 */
       LDNS_EDNS_CLIENT_TAG = 16, /* draft-bellis-dnsop-edns-tags-01 */
       LDNS_EDNS_REPORT_CHANNEL = 18, /* RFC9567 */
       LDNS_EDNS_UNBOUND_CACHEDB_TESTFRAME_TEST = 65534
};
typedef enum sldns_enum_edns_option sldns_edns_option;

enum sldns_enum_ede_code
{
       LDNS_EDE_NONE = -1, /* EDE undefined for internal use */
       LDNS_EDE_OTHER = 0,
       LDNS_EDE_UNSUPPORTED_DNSKEY_ALG = 1,
       LDNS_EDE_UNSUPPORTED_DS_DIGEST = 2,
       LDNS_EDE_STALE_ANSWER = 3,
       LDNS_EDE_FORGED_ANSWER = 4,
       LDNS_EDE_DNSSEC_INDETERMINATE = 5,
       LDNS_EDE_DNSSEC_BOGUS = 6,
       LDNS_EDE_SIGNATURE_EXPIRED = 7,
       LDNS_EDE_SIGNATURE_NOT_YET_VALID = 8,
       LDNS_EDE_DNSKEY_MISSING = 9,
       LDNS_EDE_RRSIGS_MISSING = 10,
       LDNS_EDE_NO_ZONE_KEY_BIT_SET = 11,
       LDNS_EDE_NSEC_MISSING = 12,
       LDNS_EDE_CACHED_ERROR = 13,
       LDNS_EDE_NOT_READY = 14,
       LDNS_EDE_BLOCKED = 15,
       LDNS_EDE_CENSORED = 16,
       LDNS_EDE_FILTERED = 17,
       LDNS_EDE_PROHIBITED = 18,
       LDNS_EDE_STALE_NXDOMAIN_ANSWER = 19,
       LDNS_EDE_NOT_AUTHORITATIVE = 20,
       LDNS_EDE_NOT_SUPPORTED = 21,
       LDNS_EDE_NO_REACHABLE_AUTHORITY = 22,
       LDNS_EDE_NETWORK_ERROR = 23,
       LDNS_EDE_INVALID_DATA = 24,
       LDNS_EDE_SIGNATURE_EXPIRED_BEFORE_VALID = 25,
       LDNS_EDE_TOO_EARLY = 26,
       LDNS_EDE_UNSUPPORTED_NSEC3_ITERATIONS = 27,
       LDNS_EDE_BADPROXYPOLICY = 28,
       LDNS_EDE_SYNTHESIZED = 29
};
typedef enum sldns_enum_ede_code sldns_ede_code;

#define LDNS_EDNS_MASK_DO_BIT 0x8000

/** TSIG and TKEY extended rcodes (16bit), 0-15 are the normal rcodes. */
#define LDNS_TSIG_ERROR_NOERROR  0
#define LDNS_TSIG_ERROR_BADSIG   16
#define LDNS_TSIG_ERROR_BADKEY   17
#define LDNS_TSIG_ERROR_BADTIME  18
#define LDNS_TSIG_ERROR_BADMODE  19
#define LDNS_TSIG_ERROR_BADNAME  20
#define LDNS_TSIG_ERROR_BADALG   21

/** DNS Cookie extended rcode */
#define LDNS_EXT_RCODE_BADCOOKIE 23

/**
* Contains all information about resource record types.
*
* This structure contains, for all rr types, the rdata fields that are defined.
*/
struct sldns_struct_rr_descriptor
{
       /** Type of the RR that is described here */
       sldns_rr_type    _type;
       /** Textual name of the RR type.  */
       const char *_name;
       /** Minimum number of rdata fields in the RRs of this type.  */
       uint8_t     _minimum;
       /** Maximum number of rdata fields in the RRs of this type.  */
       uint8_t     _maximum;
       /** Wireformat specification for the rr, i.e. the types of rdata fields in their respective order. */
       const sldns_rdf_type *_wireformat;
       /** Special rdf types */
       sldns_rdf_type _variable;
       /** Specifies whether compression can be used for dnames in this RR type. */
       sldns_rr_compress _compress;
       /** The number of DNAMEs in the _wireformat string, for parsing. */
       uint8_t _dname_count;
};
typedef struct sldns_struct_rr_descriptor sldns_rr_descriptor;

/**
* returns the resource record descriptor for the given rr type.
*
* \param[in] type the type value of the rr type
*\return the sldns_rr_descriptor for this type
*/
const sldns_rr_descriptor *sldns_rr_descript(uint16_t type);

/**
* returns the minimum number of rdata fields of the rr type this descriptor describes.
*
* \param[in]  descriptor for an rr type
* \return the minimum number of rdata fields
*/
size_t sldns_rr_descriptor_minimum(const sldns_rr_descriptor *descriptor);

/**
* returns the maximum number of rdata fields of the rr type this descriptor describes.
*
* \param[in]  descriptor for an rr type
* \return the maximum number of rdata fields
*/
size_t sldns_rr_descriptor_maximum(const sldns_rr_descriptor *descriptor);

/**
* returns the rdf type for the given rdata field number of the rr type for the given descriptor.
*
* \param[in] descriptor for an rr type
* \param[in] field the field number
* \return the rdf type for the field
*/
sldns_rdf_type sldns_rr_descriptor_field_type(const sldns_rr_descriptor *descriptor, size_t field);

/**
* retrieves a rrtype by looking up its name.
* \param[in] name a string with the name
* \return the type which corresponds with the name
*/
sldns_rr_type sldns_get_rr_type_by_name(const char *name);

/**
* retrieves a class by looking up its name.
* \param[in] name string with the name
* \return the cass which corresponds with the name
*/
sldns_rr_class sldns_get_rr_class_by_name(const char *name);

#ifdef __cplusplus
}
#endif

#endif /* LDNS_RRDEF_H */

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