hickory_proto/rr/

record_data.rs

// Copyright 2015-2023 Benjamin Fry <benjaminfry@me.com>
//
// Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
// https://apache.org/licenses/LICENSE-2.0> or the MIT license <LICENSE-MIT or
// https://opensource.org/licenses/MIT>, at your option. This file may not be
// copied, modified, or distributed except according to those terms.

//! record data enum variants
#![allow(deprecated, clippy::use_self)] // allows us to deprecate RData types

use alloc::vec::Vec;
#[cfg(test)]
use core::convert::From;
use core::net::{IpAddr, Ipv4Addr, Ipv6Addr};
use core::{cmp::Ordering, fmt};

#[cfg(feature = "serde")]
use serde::{Deserialize, Serialize};
use tracing::{trace, warn};

#[cfg(feature = "__dnssec")]
use crate::dnssec::rdata::{DNSSECRData, DS};
use crate::{
    error::ProtoResult,
    rr::{
        Name, RecordData, RecordDataDecodable,
        rdata::{
            A, AAAA, ANAME, CAA, CERT, CNAME, CSYNC, HINFO, HTTPS, MX, NAPTR, NS, NULL, OPENPGPKEY,
            OPT, PTR, SMIMEA, SOA, SRV, SSHFP, SVCB, TLSA, TSIG, TXT,
        },
        record_type::RecordType,
    },
    serialize::{
        binary::{BinDecodable, BinDecoder, BinEncodable, BinEncoder, DecodeError, Restrict},
        txt::{Lexer, ParseError, Token},
    },
};

/// Record data enum variants for all valid DNS data types.
///
/// This is used to represent the generic Record as it is read off the wire. Allows for a Record to be abstractly referenced without knowing it's internal until runtime.
///
/// [RFC 1035](https://tools.ietf.org/html/rfc1035), DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATION, November 1987
///
/// ```text
/// 3.3. Standard RRs
///
/// The following RR definitions are expected to occur, at least
/// potentially, in all classes.  In particular, NS, SOA, CNAME, and PTR
/// will be used in all classes, and have the same format in all classes.
/// Because their RDATA format is known, all domain names in the RDATA
/// section of these RRs may be compressed.
///
/// <domain-name> is a domain name represented as a series of labels, and
/// terminated by a label with zero length.  <character-string> is a single
/// length octet followed by that number of characters.  <character-string>
/// is treated as binary information, and can be up to 256 characters in
/// length (including the length octet).
/// ```
#[cfg_attr(feature = "serde", derive(Deserialize, Serialize))]
#[derive(Debug, PartialEq, Clone, Eq, Hash)]
#[non_exhaustive]
pub enum RData {
    /// ```text
    /// -- RFC 1035 -- Domain Implementation and Specification    November 1987
    ///
    /// 3.4. Internet specific RRs
    ///
    /// 3.4.1. A RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                    ADDRESS                    |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// ADDRESS         A 32 bit Internet address.
    ///
    /// Hosts that have multiple Internet addresses will have multiple A
    /// records.
    ///
    /// A records cause no additional section processing.  The RDATA section of
    /// an A line in a Zone File is an Internet address expressed as four
    /// decimal numbers separated by dots without any embedded spaces (e.g.,
    /// "10.2.0.52" or "192.0.5.6").
    /// ```
    A(A),

    /// ```text
    /// -- RFC 1886 -- IPv6 DNS Extensions              December 1995
    ///
    /// 2.2 AAAA data format
    ///
    ///    A 128 bit IPv6 address is encoded in the data portion of an AAAA
    ///    resource record in network byte order (high-order byte first).
    /// ```
    AAAA(AAAA),

    /// ```text
    /// 2.  The ANAME resource record
    ///
    ///   This document defines the "ANAME" DNS resource record type, with RR
    ///   TYPE value [TBD].
    ///
    /// 2.1.  Presentation and wire format
    ///
    ///   The ANAME presentation format is identical to that of CNAME
    ///   [RFC1033]:
    ///
    ///       owner ttl class ANAME target
    /// ```
    ANAME(ANAME),

    /// ```text
    /// -- RFC 6844          Certification Authority Authorization     January 2013
    ///
    /// 5.1.  Syntax
    ///
    /// A CAA RR contains a single property entry consisting of a tag-value
    /// pair.  Each tag represents a property of the CAA record.  The value
    /// of a CAA property is that specified in the corresponding value field.
    ///
    /// A domain name MAY have multiple CAA RRs associated with it and a
    /// given property MAY be specified more than once.
    ///
    /// The CAA data field contains one property entry.  A property entry
    /// consists of the following data fields:
    ///
    /// +0-1-2-3-4-5-6-7-|0-1-2-3-4-5-6-7-|
    /// | Flags          | Tag Length = n |
    /// +----------------+----------------+...+---------------+
    /// | Tag char 0     | Tag char 1     |...| Tag char n-1  |
    /// +----------------+----------------+...+---------------+
    /// +----------------+----------------+.....+----------------+
    /// | Value byte 0   | Value byte 1   |.....| Value byte m-1 |
    /// +----------------+----------------+.....+----------------+
    ///
    /// Where n is the length specified in the Tag length field and m is the
    /// remaining octets in the Value field (m = d - n - 2) where d is the
    /// length of the RDATA section.
    /// ```
    CAA(CAA),

    /// ```text
    /// -- RFC 4398 -- Storing Certificates in DNS       November 1987
    /// The CERT resource record (RR) has the structure given below.  Its RR
    /// type code is 37.
    ///
    ///    1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
    /// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// |             type              |             key tag           |
    /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// |   algorithm   |                                               /
    /// +---------------+            certificate or CRL                 /
    /// /                                                               /
    /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-|
    //// ```
    CERT(CERT),

    /// ```text
    ///   3.3. Standard RRs
    ///
    /// The following RR definitions are expected to occur, at least
    /// potentially, in all classes.  In particular, NS, SOA, CNAME, and PTR
    /// will be used in all classes, and have the same format in all classes.
    /// Because their RDATA format is known, all domain names in the RDATA
    /// section of these RRs may be compressed.
    ///
    /// <domain-name> is a domain name represented as a series of labels, and
    /// terminated by a label with zero length.  <character-string> is a single
    /// length octet followed by that number of characters.  <character-string>
    /// is treated as binary information, and can be up to 256 characters in
    /// length (including the length octet).
    ///
    /// 3.3.1. CNAME RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                     CNAME                     /
    ///     /                                               /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// CNAME           A <domain-name> which specifies the canonical or primary
    ///                 name for the owner.  The owner name is an alias.
    ///
    /// CNAME RRs cause no additional section processing, but name servers may
    /// choose to restart the query at the canonical name in certain cases.  See
    /// the description of name server logic in [RFC-1034] for details.
    /// ```
    CNAME(CNAME),

    /// ```text
    /// 2.1.  The CSYNC Resource Record Format
    ///
    /// 2.1.1.  The CSYNC Resource Record Wire Format
    ///
    /// The CSYNC RDATA consists of the following fields:
    ///
    ///                     1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
    /// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// |                          SOA Serial                           |
    /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// |       Flags                   |            Type Bit Map       /
    /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// /                     Type Bit Map (continued)                  /
    /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// ```
    CSYNC(CSYNC),

    /// ```text
    /// 3.3.2. HINFO RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                      CPU                      /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                       OS                      /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// CPU             A <character-string> which specifies the CPU type.
    ///
    /// OS              A <character-string> which specifies the operating
    ///                 system type.
    ///
    /// Standard values for CPU and OS can be found in [RFC-1010].
    ///
    /// HINFO records are used to acquire general information about a host.  The
    /// main use is for protocols such as FTP that can use special procedures
    /// when talking between machines or operating systems of the same type.
    /// ```
    ///
    /// `HINFO` is also used by [RFC 8482](https://tools.ietf.org/html/rfc8482)
    HINFO(HINFO),

    /// [RFC 9460, SVCB and HTTPS RRs](https://datatracker.ietf.org/doc/html/rfc9460#section-9)
    ///
    /// ```text
    /// 9.  Using Service Bindings with HTTP
    ///
    ///    The use of any protocol with SVCB requires a protocol-specific
    ///    mapping specification.  This section specifies the mapping for the
    ///    "http" and "https" URI schemes [HTTP].
    ///
    ///    To enable special handling for HTTP use cases, the HTTPS RR type is
    ///    defined as a SVCB-compatible RR type, specific to the "https" and
    ///    "http" schemes.  Clients MUST NOT perform SVCB queries or accept SVCB
    ///    responses for "https" or "http" schemes.
    ///
    ///    The presentation format of the record is:
    ///
    ///    Name TTL IN HTTPS SvcPriority TargetName SvcParams
    /// ```
    HTTPS(HTTPS),

    /// ```text
    /// 3.3.9. MX RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                  PREFERENCE                   |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                   EXCHANGE                    /
    ///     /                                               /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// PREFERENCE      A 16 bit integer which specifies the preference given to
    ///                 this RR among others at the same owner.  Lower values
    ///                 are preferred.
    ///
    /// EXCHANGE        A <domain-name> which specifies a host willing to act as
    ///                 a mail exchange for the owner name.
    ///
    /// MX records cause type A additional section processing for the host
    /// specified by EXCHANGE.  The use of MX RRs is explained in detail in
    /// [RFC-974].
    /// ```
    MX(MX),

    /// [RFC 3403 DDDS DNS Database, October 2002](https://tools.ietf.org/html/rfc3403#section-4)
    ///
    /// ```text
    /// 4.1 Packet Format
    ///
    ///   The packet format of the NAPTR RR is given below.  The DNS type code
    ///   for NAPTR is 35.
    ///
    ///      The packet format for the NAPTR record is as follows
    ///                                       1  1  1  1  1  1
    ///         0  1  2  3  4  5  6  7  8  9  0  1  2  3  4  5
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       |                     ORDER                     |
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       |                   PREFERENCE                  |
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       /                     FLAGS                     /
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       /                   SERVICES                    /
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       /                    REGEXP                     /
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       /                  REPLACEMENT                  /
    ///       /                                               /
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    ///   <character-string> and <domain-name> as used here are defined in RFC
    ///   1035 [7].
    ///
    ///   ORDER
    ///      A 16-bit unsigned integer specifying the order in which the NAPTR
    ///      records MUST be processed in order to accurately represent the
    ///      ordered list of Rules.  The ordering is from lowest to highest.
    ///      If two records have the same order value then they are considered
    ///      to be the same rule and should be selected based on the
    ///      combination of the Preference values and Services offered.
    ///
    ///   PREFERENCE
    ///      Although it is called "preference" in deference to DNS
    ///      terminology, this field is equivalent to the Priority value in the
    ///      DDDS Algorithm.  It is a 16-bit unsigned integer that specifies
    ///      the order in which NAPTR records with equal Order values SHOULD be
    ///      processed, low numbers being processed before high numbers.  This
    ///      is similar to the preference field in an MX record, and is used so
    ///      domain administrators can direct clients towards more capable
    ///      hosts or lighter weight protocols.  A client MAY look at records
    ///      with higher preference values if it has a good reason to do so
    ///      such as not supporting some protocol or service very well.
    ///
    ///      The important difference between Order and Preference is that once
    ///      a match is found the client MUST NOT consider records with a
    ///      different Order but they MAY process records with the same Order
    ///      but different Preferences.  The only exception to this is noted in
    ///      the second important Note in the DDDS algorithm specification
    ///      concerning allowing clients to use more complex Service
    ///      determination between steps 3 and 4 in the algorithm.  Preference
    ///      is used to give communicate a higher quality of service to rules
    ///      that are considered the same from an authority standpoint but not
    ///      from a simple load balancing standpoint.
    ///
    ///      It is important to note that DNS contains several load balancing
    ///      mechanisms and if load balancing among otherwise equal services
    ///      should be needed then methods such as SRV records or multiple A
    ///      records should be utilized to accomplish load balancing.
    ///
    ///   FLAGS
    ///      A <character-string> containing flags to control aspects of the
    ///      rewriting and interpretation of the fields in the record.  Flags
    ///      are single characters from the set A-Z and 0-9.  The case of the
    ///      alphabetic characters is not significant.  The field can be empty.
    ///
    ///      It is up to the Application specifying how it is using this
    ///      Database to define the Flags in this field.  It must define which
    ///      ones are terminal and which ones are not.
    ///
    ///   SERVICES
    ///      A <character-string> that specifies the Service Parameters
    ///      applicable to this this delegation path.  It is up to the
    ///      Application Specification to specify the values found in this
    ///      field.
    ///
    ///   REGEXP
    ///      A <character-string> containing a substitution expression that is
    ///      applied to the original string held by the client in order to
    ///      construct the next domain name to lookup.  See the DDDS Algorithm
    ///      specification for the syntax of this field.
    ///
    ///      As stated in the DDDS algorithm, The regular expressions MUST NOT
    ///      be used in a cumulative fashion, that is, they should only be
    ///      applied to the original string held by the client, never to the
    ///      domain name produced by a previous NAPTR rewrite.  The latter is
    ///      tempting in some applications but experience has shown such use to
    ///      be extremely fault sensitive, very error prone, and extremely
    ///      difficult to debug.
    ///
    ///   REPLACEMENT
    ///      A <domain-name> which is the next domain-name to query for
    ///      depending on the potential values found in the flags field.  This
    ///      field is used when the regular expression is a simple replacement
    ///      operation.  Any value in this field MUST be a fully qualified
    ///      domain-name.  Name compression is not to be used for this field.
    ///
    ///      This field and the REGEXP field together make up the Substitution
    ///      Expression in the DDDS Algorithm.  It is simply a historical
    ///      optimization specifically for DNS compression that this field
    ///      exists.  The fields are also mutually exclusive.  If a record is
    ///      returned that has values for both fields then it is considered to
    ///      be in error and SHOULD be either ignored or an error returned.
    /// ```
    NAPTR(NAPTR),

    /// ```text
    /// 3.3.10. NULL RDATA format (EXPERIMENTAL)
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                  <anything>                   /
    ///     /                                               /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// Anything at all may be in the RDATA field so long as it is 65535 octets
    /// or less.
    ///
    /// NULL records cause no additional section processing.  NULL RRs are not
    /// allowed in Zone Files.  NULLs are used as placeholders in some
    /// experimental extensions of the DNS.
    /// ```
    NULL(NULL),

    /// ```text
    /// 3.3.11. NS RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                   NSDNAME                     /
    ///     /                                               /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// NSDNAME         A <domain-name> which specifies a host which should be
    ///                 authoritative for the specified class and domain.
    ///
    /// NS records cause both the usual additional section processing to locate
    /// a type A record, and, when used in a referral, a special search of the
    /// zone in which they reside for glue information.
    ///
    /// The NS RR states that the named host should be expected to have a zone
    /// starting at owner name of the specified class.  Note that the class may
    /// not indicate the protocol family which should be used to communicate
    /// with the host, although it is typically a strong hint.  For example,
    /// hosts which are name servers for either Internet (IN) or Hesiod (HS)
    /// class information are normally queried using IN class protocols.
    /// ```
    NS(NS),

    /// [RFC 7929](https://tools.ietf.org/html/rfc7929#section-2.1)
    ///
    /// ```text
    /// The RDATA portion of an OPENPGPKEY resource record contains a single
    /// value consisting of a Transferable Public Key formatted as specified
    /// in [RFC4880].
    /// ```
    OPENPGPKEY(OPENPGPKEY),

    /// ```text
    /// RFC 6891                   EDNS(0) Extensions                 April 2013
    /// 6.1.2.  Wire Format
    ///
    ///        +------------+--------------+------------------------------+
    ///        | Field Name | Field Type   | Description                  |
    ///        +------------+--------------+------------------------------+
    ///        | NAME       | domain name  | MUST be 0 (root domain)      |
    ///        | TYPE       | u_int16_t    | OPT (41)                     |
    ///        | CLASS      | u_int16_t    | requestor's UDP payload size |
    ///        | TTL        | u_int32_t    | extended RCODE and flags     |
    ///        | RDLEN      | u_int16_t    | length of all RDATA          |
    ///        | RDATA      | octet stream | {attribute,value} pairs      |
    ///        +------------+--------------+------------------------------+
    ///
    /// The variable part of an OPT RR may contain zero or more options in
    /// the RDATA.  Each option MUST be treated as a bit field.  Each option
    /// is encoded as:
    ///
    ///                   +0 (MSB)                            +1 (LSB)
    ///        +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
    ///     0: |                          OPTION-CODE                          |
    ///        +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
    ///     2: |                         OPTION-LENGTH                         |
    ///        +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
    ///     4: |                                                               |
    ///        /                          OPTION-DATA                          /
    ///        /                                                               /
    ///        +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
    /// ```
    OPT(OPT),

    /// ```text
    /// 3.3.12. PTR RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                   PTRDNAME                    /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// PTRDNAME        A <domain-name> which points to some location in the
    ///                 domain name space.
    ///
    /// PTR records cause no additional section processing.  These RRs are used
    /// in special domains to point to some other location in the domain space.
    /// These records are simple data, and don't imply any special processing
    /// similar to that performed by CNAME, which identifies aliases.  See the
    /// description of the IN-ADDR.ARPA domain for an example.
    /// ```
    PTR(PTR),

    /// [RFC 8162](https://datatracker.ietf.org/doc/html/rfc8162#section-2)
    ///
    /// > The SMIMEA wire format and presentation format are the same as for
    /// > the [TLSA](Self::TLSA) record
    SMIMEA(SMIMEA),

    /// ```text
    /// 3.3.13. SOA RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                     MNAME                     /
    ///     /                                               /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                     RNAME                     /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                    SERIAL                     |
    ///     |                                               |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                    REFRESH                    |
    ///     |                                               |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                     RETRY                     |
    ///     |                                               |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                    EXPIRE                     |
    ///     |                                               |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                    MINIMUM                    |
    ///     |                                               |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// MNAME           The <domain-name> of the name server that was the
    ///                 original or primary source of data for this zone.
    ///
    /// RNAME           A <domain-name> which specifies the mailbox of the
    ///                 person responsible for this zone.
    ///
    /// SERIAL          The unsigned 32 bit version number of the original copy
    ///                 of the zone.  Zone transfers preserve this value.  This
    ///                 value wraps and should be compared using sequence space
    ///                 arithmetic.
    ///
    /// REFRESH         A 32 bit time interval before the zone should be
    ///                 refreshed.
    ///
    /// RETRY           A 32 bit time interval that should elapse before a
    ///                 failed refresh should be retried.
    ///
    /// EXPIRE          A 32 bit time value that specifies the upper limit on
    ///                 the time interval that can elapse before the zone is no
    ///                 longer authoritative.
    ///
    /// MINIMUM         The unsigned 32 bit minimum TTL field that should be
    ///                 exported with any RR from this zone.
    ///
    /// SOA records cause no additional section processing.
    ///
    /// All times are in units of seconds.
    ///
    /// Most of these fields are pertinent only for name server maintenance
    /// operations.  However, MINIMUM is used in all query operations that
    /// retrieve RRs from a zone.  Whenever a RR is sent in a response to a
    /// query, the TTL field is set to the maximum of the TTL field from the RR
    /// and the MINIMUM field in the appropriate SOA.  Thus MINIMUM is a lower
    /// bound on the TTL field for all RRs in a zone.  Note that this use of
    /// MINIMUM should occur when the RRs are copied into the response and not
    /// when the zone is loaded from a Zone File or via a zone transfer.  The
    /// reason for this provision is to allow future dynamic update facilities to
    /// change the SOA RR with known semantics.
    /// ```
    SOA(SOA),

    /// ```text
    /// RFC 2782                       DNS SRV RR                  February 2000
    ///
    /// The format of the SRV RR
    ///
    ///  _Service._Proto.Name TTL Class SRV Priority Weight Port Target
    /// ```
    SRV(SRV),

    /// [RFC 4255](https://tools.ietf.org/html/rfc4255#section-3.1)
    ///
    /// ```text
    /// 3.1.  The SSHFP RDATA Format
    ///
    ///    The RDATA for a SSHFP RR consists of an algorithm number, fingerprint
    ///    type and the fingerprint of the public host key.
    ///
    ///        1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
    ///        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    ///        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///        |   algorithm   |    fp type    |                               /
    ///        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               /
    ///        /                                                               /
    ///        /                          fingerprint                          /
    ///        /                                                               /
    ///        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///
    /// 3.1.1.  Algorithm Number Specification
    ///
    ///    This algorithm number octet describes the algorithm of the public
    ///    key.  The following values are assigned:
    ///
    ///           Value    Algorithm name
    ///           -----    --------------
    ///           0        reserved
    ///           1        RSA
    ///           2        DSS
    ///
    ///    Reserving other types requires IETF consensus [4].
    ///
    /// 3.1.2.  Fingerprint Type Specification
    ///
    ///    The fingerprint type octet describes the message-digest algorithm
    ///    used to calculate the fingerprint of the public key.  The following
    ///    values are assigned:
    ///
    ///           Value    Fingerprint type
    ///           -----    ----------------
    ///           0        reserved
    ///           1        SHA-1
    ///
    ///    Reserving other types requires IETF consensus [4].
    ///
    ///    For interoperability reasons, as few fingerprint types as possible
    ///    should be reserved.  The only reason to reserve additional types is
    ///    to increase security.
    ///
    /// 3.1.3.  Fingerprint
    ///
    ///    The fingerprint is calculated over the public key blob as described
    ///    in [7].
    ///
    ///    The message-digest algorithm is presumed to produce an opaque octet
    ///    string output, which is placed as-is in the RDATA fingerprint field.
    /// ```
    ///
    /// The algorithm and fingerprint type values have been updated in
    /// [RFC 6594](https://tools.ietf.org/html/rfc6594) and
    /// [RFC 7479](https://tools.ietf.org/html/rfc7479).
    SSHFP(SSHFP),

    /// [RFC 9460, SVCB and HTTPS RRs](https://datatracker.ietf.org/doc/html/rfc9460#section-2)
    ///
    /// ```text
    /// 2.  The SVCB Record Type
    ///
    ///    The SVCB DNS RR type (RR type 64) is used to locate alternative
    ///    endpoints for a service.
    ///
    ///    The algorithm for resolving SVCB records and associated address
    ///    records is specified in Section 3.
    ///
    ///    Other SVCB-compatible RR types can also be defined as needed (see
    ///    Section 6).  In particular, the HTTPS RR (RR type 65) provides
    ///    special handling for the case of "https" origins as described in
    ///    Section 9.
    ///
    ///    SVCB RRs are extensible by a list of SvcParams, which are pairs
    ///    consisting of a SvcParamKey and a SvcParamValue.  Each SvcParamKey
    ///    has a presentation name and a registered number.  Values are in a
    ///    format specific to the SvcParamKey.  Each SvcParam has a specified
    ///    presentation format (used in zone files) and wire encoding (e.g.,
    ///    domain names, binary data, or numeric values).  The initial
    ///    SvcParamKeys and their formats are defined in Section 7.
    /// ```
    SVCB(SVCB),

    /// [RFC 6698, DNS-Based Authentication for TLS](https://tools.ietf.org/html/rfc6698#section-2.1)
    ///
    /// ```text
    ///                         1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
    ///     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    ///    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///    |  Cert. Usage  |   Selector    | Matching Type |               /
    ///    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+               /
    ///    /                                                               /
    ///    /                 Certificate Association Data                  /
    ///    /                                                               /
    ///    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// ```
    TLSA(TLSA),

    /// [RFC 8945, Secret Key Transaction Authentication for DNS](https://tools.ietf.org/html/rfc8945#section-4.2)
    ///
    /// ```text
    /// 4.2.  TSIG Record Format
    ///
    ///   The fields of the TSIG RR are described below.  All multi-octet
    ///   integers in the record are sent in network byte order (see
    ///   Section 2.3.2 of [RFC1035]).
    ///
    ///   NAME:  The name of the key used, in domain name syntax.  The name
    ///      should reflect the names of the hosts and uniquely identify the
    ///      key among a set of keys these two hosts may share at any given
    ///      time.  For example, if hosts A.site.example and B.example.net
    ///      share a key, possibilities for the key name include
    ///      <id>.A.site.example, <id>.B.example.net, and
    ///      <id>.A.site.example.B.example.net.  It should be possible for more
    ///      than one key to be in simultaneous use among a set of interacting
    ///      hosts.  This allows for periodic key rotation as per best
    ///      operational practices, as well as algorithm agility as indicated
    ///      by [RFC7696].
    ///
    ///      The name may be used as a local index to the key involved, but it
    ///      is recommended that it be globally unique.  Where a key is just
    ///      shared between two hosts, its name actually need only be
    ///      meaningful to them, but it is recommended that the key name be
    ///      mnemonic and incorporate the names of participating agents or
    ///      resources as suggested above.
    ///
    ///   TYPE:  This MUST be TSIG (250: Transaction SIGnature).
    ///
    ///   CLASS:  This MUST be ANY.
    ///
    ///   TTL:  This MUST be 0.
    ///
    ///   RDLENGTH:  (variable)
    ///
    ///   RDATA:  The RDATA for a TSIG RR consists of a number of fields,
    ///      described below:
    ///
    ///                            1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
    ///        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    ///       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///       /                         Algorithm Name                        /
    ///       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///       |                                                               |
    ///       |          Time Signed          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///       |                               |            Fudge              |
    ///       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///       |          MAC Size             |                               /
    ///       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+             MAC               /
    ///       /                                                               /
    ///       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///       |          Original ID          |            Error              |
    ///       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///       |          Other Len            |                               /
    ///       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+           Other Data          /
    ///       /                                                               /
    ///       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///
    ///   The contents of the RDATA fields are:
    ///
    ///   Algorithm Name:
    ///      an octet sequence identifying the TSIG algorithm in the domain
    ///      name syntax.  (Allowed names are listed in Table 3.)  The name is
    ///      stored in the DNS name wire format as described in [RFC1034].  As
    ///      per [RFC3597], this name MUST NOT be compressed.
    ///
    ///   Time Signed:
    ///      an unsigned 48-bit integer containing the time the message was
    ///      signed as seconds since 00:00 on 1970-01-01 UTC, ignoring leap
    ///      seconds.
    ///
    ///   Fudge:
    ///      an unsigned 16-bit integer specifying the allowed time difference
    ///      in seconds permitted in the Time Signed field.
    ///
    ///   MAC Size:
    ///      an unsigned 16-bit integer giving the length of the MAC field in
    ///      octets.  Truncation is indicated by a MAC Size less than the size
    ///      of the keyed hash produced by the algorithm specified by the
    ///      Algorithm Name.
    ///
    ///   MAC:
    ///      a sequence of octets whose contents are defined by the TSIG
    ///      algorithm used, possibly truncated as specified by the MAC Size.
    ///      The length of this field is given by the MAC Size.  Calculation of
    ///      the MAC is detailed in Section 4.3.
    ///
    ///   Original ID:
    ///      an unsigned 16-bit integer holding the message ID of the original
    ///      request message.  For a TSIG RR on a request, it is set equal to
    ///      the DNS message ID.  In a TSIG attached to a response -- or in
    ///      cases such as the forwarding of a dynamic update request -- the
    ///      field contains the ID of the original DNS request.
    ///
    ///   Error:
    ///      in responses, an unsigned 16-bit integer containing the extended
    ///      RCODE covering TSIG processing.  In requests, this MUST be zero.
    ///
    ///   Other Len:
    ///      an unsigned 16-bit integer specifying the length of the Other Data
    ///      field in octets.
    ///
    ///   Other Data:
    ///      additional data relevant to the TSIG record.  In responses, this
    ///      will be empty (i.e., Other Len will be zero) unless the content of
    ///      the Error field is BADTIME, in which case it will be a 48-bit
    ///      unsigned integer containing the server's current time as the
    ///      number of seconds since 00:00 on 1970-01-01 UTC, ignoring leap
    ///      seconds (see Section 5.2.3).  This document assigns no meaning to
    ///      its contents in requests.
    /// ```
    TSIG(TSIG),

    /// ```text
    /// 3.3.14. TXT RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                   TXT-DATA                    /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// TXT-DATA        One or more <character-string>s.
    ///
    /// TXT RRs are used to hold descriptive text.  The semantics of the text
    /// depends on the domain where it is found.
    /// ```
    TXT(TXT),

    /// A DNSSEC- or SIG(0)- specific record. See `DNSSECRData` for details.
    ///
    /// These types are in `DNSSECRData` to make them easy to disable when
    /// crypto functionality isn't needed.
    #[cfg(feature = "__dnssec")]
    DNSSEC(DNSSECRData),

    /// Unknown RecordData is for record types not supported by Hickory DNS
    Unknown {
        /// RecordType code
        code: RecordType,
        /// RData associated to the record
        rdata: NULL,
    },

    /// Update record with RDLENGTH = 0 (RFC2136)
    Update0(RecordType),

    /// This corresponds to a record type of 0, unspecified
    #[deprecated(note = "Use None for the RData in the resource record instead")]
    ZERO,
}

impl RData {
    fn to_bytes(&self) -> Vec<u8> {
        let mut buf: Vec<u8> = Vec::new();
        {
            let mut encoder: BinEncoder<'_> = BinEncoder::new(&mut buf);
            self.emit(&mut encoder).unwrap_or_else(|_| {
                warn!("could not encode RDATA: {:?}", self);
            });
        }
        buf
    }

    /// Converts this to a Recordtype
    pub fn record_type(&self) -> RecordType {
        match self {
            Self::A(..) => RecordType::A,
            Self::AAAA(..) => RecordType::AAAA,
            Self::ANAME(..) => RecordType::ANAME,
            Self::CAA(..) => RecordType::CAA,
            Self::CERT(..) => RecordType::CERT,
            Self::CNAME(..) => RecordType::CNAME,
            Self::CSYNC(..) => RecordType::CSYNC,
            Self::HINFO(..) => RecordType::HINFO,
            Self::HTTPS(..) => RecordType::HTTPS,
            Self::MX(..) => RecordType::MX,
            Self::NAPTR(..) => RecordType::NAPTR,
            Self::NS(..) => RecordType::NS,
            Self::NULL(..) => RecordType::NULL,
            Self::OPENPGPKEY(..) => RecordType::OPENPGPKEY,
            Self::OPT(..) => RecordType::OPT,
            Self::PTR(..) => RecordType::PTR,
            Self::SMIMEA(..) => RecordType::SMIMEA,
            Self::SOA(..) => RecordType::SOA,
            Self::SRV(..) => RecordType::SRV,
            Self::SSHFP(..) => RecordType::SSHFP,
            Self::SVCB(..) => RecordType::SVCB,
            Self::TLSA(..) => RecordType::TLSA,
            Self::TSIG(..) => RecordType::TSIG,
            Self::TXT(..) => RecordType::TXT,
            #[cfg(feature = "__dnssec")]
            Self::DNSSEC(rdata) => DNSSECRData::to_record_type(rdata),
            Self::Unknown { code, .. } => *code,
            Self::Update0(record_type) => *record_type,
            Self::ZERO => RecordType::ZERO,
        }
    }

    /// If this is an A or AAAA record type, then an IpAddr will be returned
    pub fn ip_addr(&self) -> Option<IpAddr> {
        match self {
            Self::A(a) => Some(IpAddr::from(a.0)),
            Self::AAAA(aaaa) => Some(IpAddr::from(aaaa.0)),
            _ => None,
        }
    }

    /// Read data from the decoder
    pub fn read(
        decoder: &mut BinDecoder<'_>,
        record_type: RecordType,
        length: Restrict<u16>,
    ) -> Result<Self, DecodeError> {
        let start_idx = decoder.index();

        let result = match record_type {
            RecordType::A => {
                trace!("reading A");
                A::read(decoder).map(Self::A)
            }
            RecordType::AAAA => {
                trace!("reading AAAA");
                AAAA::read(decoder).map(Self::AAAA)
            }
            RecordType::ANAME => {
                trace!("reading ANAME");
                ANAME::read(decoder).map(Self::ANAME)
            }
            rt @ RecordType::ANY | rt @ RecordType::AXFR | rt @ RecordType::IXFR => {
                return Err(DecodeError::UnknownRecordTypeValue(rt.into()));
            }
            RecordType::CAA => {
                trace!("reading CAA");
                CAA::read_data(decoder, length).map(Self::CAA)
            }
            RecordType::CERT => {
                trace!("reading CERT");
                CERT::read_data(decoder, length).map(Self::CERT)
            }
            RecordType::CNAME => {
                trace!("reading CNAME");
                CNAME::read(decoder).map(Self::CNAME)
            }
            RecordType::CSYNC => {
                trace!("reading CSYNC");
                CSYNC::read_data(decoder, length).map(Self::CSYNC)
            }
            RecordType::HINFO => {
                trace!("reading HINFO");
                HINFO::read_data(decoder, length).map(Self::HINFO)
            }
            RecordType::HTTPS => {
                trace!("reading HTTPS");
                HTTPS::read_data(decoder, length).map(Self::HTTPS)
            }
            RecordType::ZERO => {
                trace!("reading EMPTY");
                // we should never get here, since ZERO should be 0 length, and None in the Record.
                //   this invariant is verified below, and the decoding will fail with an err.
                #[allow(deprecated)]
                Ok(Self::ZERO)
            }
            RecordType::MX => {
                trace!("reading MX");
                MX::read_data(decoder, length).map(Self::MX)
            }
            RecordType::NAPTR => {
                trace!("reading NAPTR");
                NAPTR::read_data(decoder, length).map(Self::NAPTR)
            }
            RecordType::NULL => {
                trace!("reading NULL");
                NULL::read_data(decoder, length).map(Self::NULL)
            }
            RecordType::NS => {
                trace!("reading NS");
                NS::read(decoder).map(Self::NS)
            }
            RecordType::OPENPGPKEY => {
                trace!("reading OPENPGPKEY");
                OPENPGPKEY::read_data(decoder, length).map(Self::OPENPGPKEY)
            }
            RecordType::OPT => {
                trace!("reading OPT");
                OPT::read_data(decoder, length).map(Self::OPT)
            }
            RecordType::PTR => {
                trace!("reading PTR");
                PTR::read(decoder).map(Self::PTR)
            }
            RecordType::SMIMEA => {
                trace!("reading SMIMEA");
                SMIMEA::read_data(decoder, length).map(Self::SMIMEA)
            }
            RecordType::SOA => {
                trace!("reading SOA");
                SOA::read_data(decoder, length).map(Self::SOA)
            }
            RecordType::SRV => {
                trace!("reading SRV");
                SRV::read_data(decoder, length).map(Self::SRV)
            }
            RecordType::SSHFP => {
                trace!("reading SSHFP");
                SSHFP::read_data(decoder, length).map(Self::SSHFP)
            }
            RecordType::SVCB => {
                trace!("reading SVCB");
                SVCB::read_data(decoder, length).map(Self::SVCB)
            }
            RecordType::TLSA => {
                trace!("reading TLSA");
                TLSA::read_data(decoder, length).map(Self::TLSA)
            }
            RecordType::TSIG => {
                trace!("reading TSIG");
                TSIG::read_data(decoder, length).map(Self::TSIG)
            }
            RecordType::TXT => {
                trace!("reading TXT");
                TXT::read_data(decoder, length).map(Self::TXT)
            }
            #[cfg(feature = "__dnssec")]
            r if r.is_dnssec() => DNSSECRData::read(decoder, record_type, length).map(Self::DNSSEC),
            record_type => {
                trace!("reading Unknown record: {}", record_type);
                NULL::read_data(decoder, length).map(|rdata| Self::Unknown {
                    code: record_type,
                    rdata,
                })
            }
        };

        // we should have read rdata_length, but we did not
        let read = decoder.index() - start_idx;
        length
            .map(|u| u as usize)
            .verify_unwrap(|rdata_length| read == *rdata_length)
            .map_err(|rdata_length| DecodeError::IncorrectRDataLengthRead {
                read,
                len: rdata_length,
            })?;

        result
    }

    /// Parse RData from a string
    pub fn try_from_str(record_type: RecordType, s: &str) -> Result<Self, ParseError> {
        let mut lexer = Lexer::new(s);
        let mut rdata = Vec::new();

        while let Some(token) = lexer.next_token()? {
            match token {
                Token::List(list) => rdata.extend(list),
                Token::CharData(s) => rdata.push(s),
                Token::EOL | Token::Blank => (),
                _ => {
                    return Err(ParseError::from(format!(
                        "unexpected token in record data: {token:?}"
                    )));
                }
            }
        }

        Self::from_tokens(record_type, rdata.iter().map(AsRef::as_ref), None)
    }

    /// Attempts to parse a stream of tokenized strs into the RData of the specified record type
    /// Parse the RData from a set of Tokens
    pub(crate) fn from_tokens<'i, I: Iterator<Item = &'i str>>(
        record_type: RecordType,
        tokens: I,
        origin: Option<&Name>,
    ) -> Result<Self, ParseError> {
        let rdata = match record_type {
            RecordType::A => Self::A(A::from_tokens(tokens)?),
            RecordType::AAAA => Self::AAAA(AAAA::from_tokens(tokens)?),
            RecordType::ANAME => Self::ANAME(ANAME(Name::from_tokens(tokens, origin)?)),
            RecordType::ANY => return Err(ParseError::from("parsing ANY doesn't make sense")),
            RecordType::AXFR => return Err(ParseError::from("parsing AXFR doesn't make sense")),
            RecordType::CAA => Self::CAA(CAA::from_tokens(tokens)?),
            RecordType::CERT => Self::CERT(CERT::from_tokens(tokens)?),
            RecordType::CNAME => Self::CNAME(CNAME(Name::from_tokens(tokens, origin)?)),
            RecordType::CSYNC => Self::CSYNC(CSYNC::from_tokens(tokens)?),
            RecordType::HINFO => Self::HINFO(HINFO::from_tokens(tokens)?),
            RecordType::HTTPS => Self::HTTPS(HTTPS(SVCB::from_tokens(tokens)?)),
            RecordType::IXFR => return Err(ParseError::from("parsing IXFR doesn't make sense")),
            RecordType::MX => Self::MX(MX::from_tokens(tokens, origin)?),
            RecordType::NAPTR => Self::NAPTR(NAPTR::from_tokens(tokens, origin)?),
            RecordType::NULL => {
                return Err(ParseError::Message(
                    "parse is not implemented for NULL record",
                ));
            }
            RecordType::NS => Self::NS(NS(Name::from_tokens(tokens, origin)?)),
            RecordType::OPENPGPKEY => Self::OPENPGPKEY(OPENPGPKEY::from_tokens(tokens)?),
            RecordType::OPT => return Err(ParseError::from("parsing OPT doesn't make sense")),
            RecordType::PTR => Self::PTR(PTR(Name::from_tokens(tokens, origin)?)),
            RecordType::SMIMEA => Self::SMIMEA(SMIMEA::from_tokens(tokens)?),
            RecordType::SOA => Self::SOA(SOA::from_tokens(tokens, origin)?),
            RecordType::SRV => Self::SRV(SRV::from_tokens(tokens, origin)?),
            RecordType::SSHFP => Self::SSHFP(SSHFP::from_tokens(tokens)?),
            RecordType::SVCB => Self::SVCB(SVCB::from_tokens(tokens)?),
            RecordType::TLSA => Self::TLSA(TLSA::from_tokens(tokens)?),
            RecordType::TXT => Self::TXT(TXT::from_tokens(tokens)?),
            RecordType::SIG => return Err(ParseError::from("parsing SIG doesn't make sense")),
            RecordType::DNSKEY => {
                return Err(ParseError::from("DNSKEY should be dynamically generated"));
            }
            RecordType::CDNSKEY => {
                return Err(ParseError::from("CDNSKEY should be dynamically generated"));
            }
            RecordType::KEY => return Err(ParseError::from("KEY should be dynamically generated")),
            #[cfg(feature = "__dnssec")]
            RecordType::DS => Self::DNSSEC(DNSSECRData::DS(DS::from_tokens(tokens)?)),
            #[cfg(not(feature = "__dnssec"))]
            RecordType::DS => return Err(ParseError::from("DS should be dynamically generated")),
            RecordType::CDS => return Err(ParseError::from("CDS should be dynamically generated")),
            RecordType::NSEC => {
                return Err(ParseError::from("NSEC should be dynamically generated"));
            }
            RecordType::NSEC3 => {
                return Err(ParseError::from("NSEC3 should be dynamically generated"));
            }
            RecordType::NSEC3PARAM => {
                return Err(ParseError::from(
                    "NSEC3PARAM should be dynamically generated",
                ));
            }
            RecordType::RRSIG => {
                return Err(ParseError::from("RRSIG should be dynamically generated"));
            }
            RecordType::TSIG => return Err(ParseError::from("TSIG is only used during AXFR")),
            #[allow(deprecated)]
            RecordType::ZERO => Self::ZERO,
            r @ RecordType::Unknown(..) => {
                // TODO: add a way to associate generic record types to the zone
                return Err(ParseError::UnsupportedRecordType(r));
            }
        };

        Ok(rdata)
    }
}

impl BinEncodable for RData {
    /// [RFC 4034](https://tools.ietf.org/html/rfc4034#section-6), DNSSEC Resource Records, March 2005
    ///
    /// ```text
    /// 6.2.  Canonical RR Form
    ///
    ///    For the purposes of DNS security, the canonical form of an RR is the
    ///    wire format of the RR where:
    ///
    ///    ...
    ///
    ///    3.  if the type of the RR is NS, MD, MF, CNAME, SOA, MB, MG, MR, PTR,
    ///        HINFO, MINFO, MX, HINFO, RP, AFSDB, RT, SIG, PX, NXT, NAPTR, KX,
    ///        SRV, DNAME, A6, RRSIG, or (rfc6840 removes NSEC), all uppercase
    ///        US-ASCII letters in the DNS names contained within the RDATA are replaced
    ///        by the corresponding lowercase US-ASCII letters;
    /// ```
    ///
    /// Canonical name form for all non-1035 records:
    ///   [RFC 3597](https://tools.ietf.org/html/rfc3597)
    /// ```text
    ///  4.  Domain Name Compression
    ///
    ///   RRs containing compression pointers in the RDATA part cannot be
    ///   treated transparently, as the compression pointers are only
    ///   meaningful within the context of a DNS message.  Transparently
    ///   copying the RDATA into a new DNS message would cause the compression
    ///   pointers to point at the corresponding location in the new message,
    ///   which now contains unrelated data.  This would cause the compressed
    ///   name to be corrupted.
    ///
    ///   To avoid such corruption, servers MUST NOT compress domain names
    ///   embedded in the RDATA of types that are class-specific or not well-
    ///   known.  This requirement was stated in [RFC1123] without defining the
    ///   term "well-known"; it is hereby specified that only the RR types
    ///   defined in [RFC1035] are to be considered "well-known".
    ///
    ///   The specifications of a few existing RR types have explicitly allowed
    ///   compression contrary to this specification: [RFC2163] specified that
    ///   compression applies to the PX RR, and [RFC2535] allowed compression
    ///   in SIG RRs and NXT RRs records.  Since this specification disallows
    ///   compression in these cases, it is an update to [RFC2163] (section 4)
    ///   and [RFC2535] (sections 4.1.7 and 5.2).
    ///
    ///   Receiving servers MUST decompress domain names in RRs of well-known
    ///   type, and SHOULD also decompress RRs of type RP, AFSDB, RT, SIG, PX,
    ///   NXT, NAPTR, and SRV (although the current specification of the SRV RR
    ///   in [RFC2782] prohibits compression, [RFC2052] mandated it, and some
    ///   servers following that earlier specification are still in use).
    ///
    ///   Future specifications for new RR types that contain domain names
    ///   within their RDATA MUST NOT allow the use of name compression for
    ///   those names, and SHOULD explicitly state that the embedded domain
    ///   names MUST NOT be compressed.
    ///
    ///   As noted in [RFC1123], the owner name of an RR is always eligible for
    ///   compression.
    ///
    ///   ...
    ///   As a courtesy to implementors, it is hereby noted that the complete
    ///    set of such previously published RR types that contain embedded
    ///    domain names, and whose DNSSEC canonical form therefore involves
    ///   downcasing according to the DNS rules for character comparisons,
    ///   consists of the RR types NS, MD, MF, CNAME, SOA, MB, MG, MR, PTR,
    ///   HINFO, MINFO, MX, HINFO, RP, AFSDB, RT, SIG, PX, NXT, NAPTR, KX, SRV,
    ///   DNAME, and A6.
    ///   ...
    /// ```
    fn emit(&self, encoder: &mut BinEncoder<'_>) -> ProtoResult<()> {
        match self {
            Self::A(address) => address.emit(encoder),
            Self::AAAA(address) => address.emit(encoder),
            Self::ANAME(name) => name.emit(encoder),
            Self::CAA(caa) => caa.emit(encoder),
            Self::CERT(cert) => cert.emit(encoder),
            Self::CNAME(cname) => cname.emit(encoder),
            Self::NS(ns) => ns.emit(encoder),
            Self::PTR(ptr) => ptr.emit(encoder),
            Self::CSYNC(csync) => csync.emit(encoder),
            Self::HINFO(hinfo) => hinfo.emit(encoder),
            Self::HTTPS(https) => https.emit(encoder),
            Self::ZERO => Ok(()),
            Self::MX(mx) => mx.emit(encoder),
            Self::NAPTR(naptr) => naptr.emit(encoder),
            Self::NULL(null) => null.emit(encoder),
            Self::OPENPGPKEY(openpgpkey) => openpgpkey.emit(encoder),
            Self::OPT(opt) => opt.emit(encoder),
            Self::SMIMEA(opt) => opt.emit(encoder),
            Self::SOA(soa) => soa.emit(encoder),
            Self::SRV(srv) => srv.emit(encoder),
            Self::SSHFP(sshfp) => sshfp.emit(encoder),
            Self::SVCB(svcb) => svcb.emit(encoder),
            Self::TLSA(tlsa) => tlsa.emit(encoder),
            Self::TSIG(tsig) => tsig.emit(encoder),
            Self::TXT(txt) => txt.emit(encoder),
            #[cfg(feature = "__dnssec")]
            Self::DNSSEC(rdata) => rdata.emit(encoder),
            Self::Unknown { rdata, .. } => rdata.emit(encoder),
            Self::Update0(_) => Ok(()),
        }
    }
}

impl RecordData for RData {
    fn try_borrow(data: &RData) -> Option<&Self> {
        Some(data)
    }

    fn record_type(&self) -> RecordType {
        self.record_type()
    }

    fn into_rdata(self) -> RData {
        self
    }

    fn is_update(&self) -> bool {
        matches!(self, RData::Update0(_))
    }
}

impl fmt::Display for RData {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
        fn w<D: fmt::Display>(f: &mut fmt::Formatter<'_>, rdata: D) -> Result<(), fmt::Error> {
            write!(f, "{rdata}")
        }

        match self {
            Self::A(address) => w(f, address),
            Self::AAAA(address) => w(f, address),
            Self::ANAME(name) => w(f, name),
            Self::CAA(caa) => w(f, caa),
            Self::CERT(cert) => w(f, cert),
            // to_lowercase for rfc4034 and rfc6840
            Self::CNAME(cname) => w(f, cname),
            Self::NS(ns) => w(f, ns),
            Self::PTR(ptr) => w(f, ptr),
            Self::CSYNC(csync) => w(f, csync),
            Self::HINFO(hinfo) => w(f, hinfo),
            Self::HTTPS(https) => w(f, https),
            Self::ZERO => Ok(()),
            // to_lowercase for rfc4034 and rfc6840
            Self::MX(mx) => w(f, mx),
            Self::NAPTR(naptr) => w(f, naptr),
            Self::NULL(null) => w(f, null),
            Self::OPENPGPKEY(openpgpkey) => w(f, openpgpkey),
            // Opt has no display representation
            Self::OPT(_) => Err(fmt::Error),
            Self::SMIMEA(smimea) => w(f, smimea),
            // to_lowercase for rfc4034 and rfc6840
            Self::SOA(soa) => w(f, soa),
            // to_lowercase for rfc4034 and rfc6840
            Self::SRV(srv) => w(f, srv),
            Self::SSHFP(sshfp) => w(f, sshfp),
            Self::SVCB(svcb) => w(f, svcb),
            Self::TLSA(tlsa) => w(f, tlsa),
            Self::TSIG(tsig) => w(f, tsig),
            Self::TXT(txt) => w(f, txt),
            #[cfg(feature = "__dnssec")]
            Self::DNSSEC(rdata) => w(f, rdata),
            Self::Unknown { rdata, .. } => w(f, rdata),
            Self::Update0(_) => w(f, "UPDATE"),
        }
    }
}

impl PartialOrd<Self> for RData {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        Some(self.cmp(other))
    }
}

impl Ord for RData {
    // RFC 4034                DNSSEC Resource Records               March 2005
    //
    // 6.3.  Canonical RR Ordering within an RRset
    //
    //    For the purposes of DNS security, RRs with the same owner name,
    //    class, and type are sorted by treating the RDATA portion of the
    //    canonical form of each RR as a left-justified unsigned octet sequence
    //    in which the absence of an octet sorts before a zero octet.
    //
    //    [RFC2181] specifies that an RRset is not allowed to contain duplicate
    //    records (multiple RRs with the same owner name, class, type, and
    //    RDATA).  Therefore, if an implementation detects duplicate RRs when
    //    putting the RRset in canonical form, it MUST treat this as a protocol
    //    error.  If the implementation chooses to handle this protocol error
    //    in the spirit of the robustness principle (being liberal in what it
    //    accepts), it MUST remove all but one of the duplicate RR(s) for the
    //    purposes of calculating the canonical form of the RRset.
    fn cmp(&self, other: &Self) -> Ordering {
        // TODO: how about we just store the bytes with the decoded data?
        //  the decoded data is useful for queries, the encoded data is needed for transfers, signing
        //  and ordering.
        self.to_bytes().cmp(&other.to_bytes())
    }
}

impl From<IpAddr> for RData {
    fn from(ip: IpAddr) -> Self {
        match ip {
            IpAddr::V4(ip) => RData::A(A(ip)),
            IpAddr::V6(ip) => RData::AAAA(AAAA(ip)),
        }
    }
}

impl From<Ipv4Addr> for RData {
    fn from(ip: Ipv4Addr) -> Self {
        RData::A(A(ip))
    }
}

impl From<Ipv6Addr> for RData {
    fn from(ip: Ipv6Addr) -> Self {
        RData::AAAA(AAAA(ip))
    }
}

#[cfg(test)]
mod tests {
    #![allow(clippy::dbg_macro, clippy::print_stdout)]

    use alloc::string::ToString;
    use core::str::FromStr;
    #[cfg(feature = "std")]
    use std::println;

    use super::*;
    use crate::rr::domain::Name;
    use crate::rr::rdata::{MX, SOA, SRV, TXT};
    use crate::serialize::binary::bin_tests::test_emit_data_set;

    fn get_data() -> Vec<(RData, Vec<u8>)> {
        vec![
            (
                RData::CNAME(CNAME(Name::from_str("www.example.com.").unwrap())),
                vec![
                    3, b'w', b'w', b'w', 7, b'e', b'x', b'a', b'm', b'p', b'l', b'e', 3, b'c',
                    b'o', b'm', 0,
                ],
            ),
            (
                RData::MX(MX::new(256, Name::from_str("n.").unwrap())),
                vec![1, 0, 1, b'n', 0],
            ),
            (
                RData::NS(NS(Name::from_str("www.example.com.").unwrap())),
                vec![
                    3, b'w', b'w', b'w', 7, b'e', b'x', b'a', b'm', b'p', b'l', b'e', 3, b'c',
                    b'o', b'm', 0,
                ],
            ),
            (
                RData::PTR(PTR(Name::from_str("www.example.com.").unwrap())),
                vec![
                    3, b'w', b'w', b'w', 7, b'e', b'x', b'a', b'm', b'p', b'l', b'e', 3, b'c',
                    b'o', b'm', 0,
                ],
            ),
            (
                RData::SOA(SOA::new(
                    Name::from_str("www.example.com.").unwrap(),
                    Name::from_str("xxx.example.com.").unwrap(),
                    u32::MAX,
                    -1,
                    -1,
                    -1,
                    u32::MAX,
                )),
                vec![
                    3, b'w', b'w', b'w', 7, b'e', b'x', b'a', b'm', b'p', b'l', b'e', 3, b'c',
                    b'o', b'm', 0, 3, b'x', b'x', b'x', 0xC0, 0x04, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
                    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
                    0xFF, 0xFF,
                ],
            ),
            (
                RData::TXT(TXT::new(vec![
                    "abcdef".to_string(),
                    "ghi".to_string(),
                    "".to_string(),
                    "j".to_string(),
                ])),
                vec![
                    6, b'a', b'b', b'c', b'd', b'e', b'f', 3, b'g', b'h', b'i', 0, 1, b'j',
                ],
            ),
            (RData::A(A::from(Ipv4Addr::UNSPECIFIED)), vec![0, 0, 0, 0]),
            (
                RData::AAAA(AAAA::from(Ipv6Addr::UNSPECIFIED)),
                vec![0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
            ),
            (
                RData::SRV(SRV::new(
                    1,
                    2,
                    3,
                    Name::from_str("www.example.com.").unwrap(),
                )),
                vec![
                    0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 3, b'w', b'w', b'w', 7, b'e', b'x', b'a',
                    b'm', b'p', b'l', b'e', 3, b'c', b'o', b'm', 0,
                ],
            ),
            (
                RData::HINFO(HINFO::new("cpu".to_string(), "os".to_string())),
                vec![3, b'c', b'p', b'u', 2, b'o', b's'],
            ),
        ]
    }

    // TODO this test kinda sucks, shows the problem with not storing the binary parts
    #[test]
    fn test_order() {
        let ordered: Vec<RData> = vec![
            RData::A(A::from(Ipv4Addr::UNSPECIFIED)),
            RData::AAAA(AAAA::from(Ipv6Addr::UNSPECIFIED)),
            RData::SRV(SRV::new(
                1,
                2,
                3,
                Name::from_str("www.example.com").unwrap(),
            )),
            RData::MX(MX::new(256, Name::from_str("n").unwrap())),
            RData::CNAME(CNAME(Name::from_str("www.example.com").unwrap())),
            RData::PTR(PTR(Name::from_str("www.example.com").unwrap())),
            RData::NS(NS(Name::from_str("www.example.com").unwrap())),
            RData::SOA(SOA::new(
                Name::from_str("www.example.com").unwrap(),
                Name::from_str("xxx.example.com").unwrap(),
                u32::MAX,
                -1,
                -1,
                -1,
                u32::MAX,
            )),
            RData::TXT(TXT::new(vec![
                "abcdef".to_string(),
                "ghi".to_string(),
                "".to_string(),
                "j".to_string(),
            ])),
        ];
        let mut unordered = vec![
            RData::CNAME(CNAME(Name::from_str("www.example.com").unwrap())),
            RData::MX(MX::new(256, Name::from_str("n").unwrap())),
            RData::PTR(PTR(Name::from_str("www.example.com").unwrap())),
            RData::NS(NS(Name::from_str("www.example.com").unwrap())),
            RData::SOA(SOA::new(
                Name::from_str("www.example.com").unwrap(),
                Name::from_str("xxx.example.com").unwrap(),
                u32::MAX,
                -1,
                -1,
                -1,
                u32::MAX,
            )),
            RData::TXT(TXT::new(vec![
                "abcdef".to_string(),
                "ghi".to_string(),
                "".to_string(),
                "j".to_string(),
            ])),
            RData::A(A::from(Ipv4Addr::UNSPECIFIED)),
            RData::AAAA(AAAA::from(Ipv6Addr::UNSPECIFIED)),
            RData::SRV(SRV::new(
                1,
                2,
                3,
                Name::from_str("www.example.com").unwrap(),
            )),
        ];

        unordered.sort();
        assert_eq!(ordered, unordered);
    }

    #[test]
    #[cfg_attr(not(feature = "std"), expect(clippy::unused_enumerate_index))]
    fn test_read() {
        for (_test_pass, (expect, binary)) in get_data().into_iter().enumerate() {
            #[cfg(feature = "std")]
            println!("test {_test_pass}: {binary:?}");
            let length = binary.len() as u16; // pre exclusive borrow
            let mut decoder = BinDecoder::new(&binary);

            assert_eq!(
                RData::read(
                    &mut decoder,
                    record_type_from_rdata(&expect),
                    Restrict::new(length)
                )
                .unwrap(),
                expect
            );
        }
    }

    fn record_type_from_rdata(rdata: &RData) -> RecordType {
        match rdata {
            RData::A(..) => RecordType::A,
            RData::AAAA(..) => RecordType::AAAA,
            RData::ANAME(..) => RecordType::ANAME,
            RData::CAA(..) => RecordType::CAA,
            RData::CERT(..) => RecordType::CERT,
            RData::CNAME(..) => RecordType::CNAME,
            RData::CSYNC(..) => RecordType::CSYNC,
            RData::HINFO(..) => RecordType::HINFO,
            RData::HTTPS(..) => RecordType::HTTPS,
            RData::MX(..) => RecordType::MX,
            RData::NAPTR(..) => RecordType::NAPTR,
            RData::NS(..) => RecordType::NS,
            RData::NULL(..) => RecordType::NULL,
            RData::OPENPGPKEY(..) => RecordType::OPENPGPKEY,
            RData::OPT(..) => RecordType::OPT,
            RData::PTR(..) => RecordType::PTR,
            RData::SMIMEA(..) => RecordType::SMIMEA,
            RData::SOA(..) => RecordType::SOA,
            RData::SRV(..) => RecordType::SRV,
            RData::SSHFP(..) => RecordType::SSHFP,
            RData::SVCB(..) => RecordType::SVCB,
            RData::TLSA(..) => RecordType::TLSA,
            RData::TSIG(..) => RecordType::TSIG,
            RData::TXT(..) => RecordType::TXT,
            #[cfg(feature = "__dnssec")]
            RData::DNSSEC(rdata) => rdata.to_record_type(),
            RData::Unknown { code, .. } => *code,
            RData::Update0(record_type) => *record_type,
            RData::ZERO => RecordType::ZERO,
        }
    }

    #[test]
    fn test_write_to() {
        test_emit_data_set(get_data(), |e, d| d.emit(e));
    }

    #[test]
    fn test_a() {
        let tokens = ["192.168.0.1"];
        let name = Name::from_str("example.com.").unwrap();
        let record =
            RData::from_tokens(RecordType::A, tokens.iter().map(AsRef::as_ref), Some(&name))
                .unwrap();

        assert_eq!(record, RData::A("192.168.0.1".parse().unwrap()));
    }

    #[test]
    fn test_a_parse() {
        let data = "192.168.0.1";
        let record = RData::try_from_str(RecordType::A, data).unwrap();

        assert_eq!(record, RData::A("192.168.0.1".parse().unwrap()));
    }

    #[test]
    fn test_aaaa() {
        let tokens = ["::1"];
        let name = Name::from_str("example.com.").unwrap();
        let record = RData::from_tokens(
            RecordType::AAAA,
            tokens.iter().map(AsRef::as_ref),
            Some(&name),
        )
        .unwrap();

        assert_eq!(record, RData::AAAA("::1".parse().unwrap()));
    }

    #[test]
    fn test_aaaa_parse() {
        let data = "::1";
        let record = RData::try_from_str(RecordType::AAAA, data).unwrap();

        assert_eq!(record, RData::AAAA("::1".parse().unwrap()));
    }

    #[test]
    fn test_ns_parse() {
        let data = "ns.example.com";
        let record = RData::try_from_str(RecordType::NS, data).unwrap();

        assert_eq!(
            record,
            RData::NS(NS(Name::from_str("ns.example.com").unwrap()))
        );
    }

    #[test]
    fn test_csync() {
        let tokens = ["123", "1", "A", "NS"];
        let name = Name::from_str("example.com.").unwrap();
        let record = RData::from_tokens(
            RecordType::CSYNC,
            tokens.iter().map(AsRef::as_ref),
            Some(&name),
        )
        .unwrap();

        assert_eq!(
            record,
            RData::CSYNC(CSYNC::new(
                123,
                true,
                false,
                [RecordType::A, RecordType::NS]
            ))
        );
    }

    #[test]
    fn test_csync_parse() {
        let data = "123 1 A NS";
        let record = RData::try_from_str(RecordType::CSYNC, data).unwrap();

        assert_eq!(
            record,
            RData::CSYNC(CSYNC::new(
                123,
                true,
                false,
                [RecordType::A, RecordType::NS]
            ))
        );
    }

    #[cfg(feature = "__dnssec")]
    #[test]
    #[allow(deprecated)]
    fn test_ds() {
        let tokens = [
            "60485",
            "5",
            "1",
            "2BB183AF5F22588179A53B0A",
            "98631FAD1A292118",
        ];
        let name = Name::from_str("dskey.example.com.").unwrap();
        let record = RData::from_tokens(
            RecordType::DS,
            tokens.iter().map(AsRef::as_ref),
            Some(&name),
        )
        .unwrap();

        assert_eq!(
            record,
            RData::DNSSEC(DNSSECRData::DS(DS::new(
                60485,
                crate::dnssec::Algorithm::RSASHA1,
                crate::dnssec::DigestType::SHA1,
                vec![
                    0x2B, 0xB1, 0x83, 0xAF, 0x5F, 0x22, 0x58, 0x81, 0x79, 0xA5, 0x3B, 0x0A, 0x98,
                    0x63, 0x1F, 0xAD, 0x1A, 0x29, 0x21, 0x18
                ]
            )))
        );
    }

    #[test]
    fn test_any() {
        let tokens = ["test"];
        let name = Name::from_str("example.com.").unwrap();
        let result = RData::from_tokens(
            RecordType::ANY,
            tokens.iter().map(AsRef::as_ref),
            Some(&name),
        );

        assert!(result.is_err());
    }

    #[test]
    fn test_dynamically_generated() {
        let dynamically_generated = vec![
            RecordType::DS,
            RecordType::CDS,
            RecordType::DNSKEY,
            RecordType::CDNSKEY,
            RecordType::KEY,
            RecordType::NSEC,
            RecordType::NSEC3,
            RecordType::NSEC3PARAM,
            RecordType::RRSIG,
        ];

        let tokens = ["test"];

        let name = Name::from_str("example.com.").unwrap();

        for record_type in dynamically_generated {
            let result =
                RData::from_tokens(record_type, tokens.iter().map(AsRef::as_ref), Some(&name));
            assert!(result.is_err());
        }
    }
}