# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license
# Copyright (C) 2001-2017 Nominum, Inc.
#
# Permission to use, copy, modify, and distribute this software and its
# documentation for any purpose with or without fee is hereby granted,
# provided that the above copyright notice and this permission notice
# appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
"""DNS Rdata Types."""
import dns.enum
import dns.exception
class RdataType(dns.enum.IntEnum):
"""DNS Rdata Type"""
TYPE0 = 0
NONE = 0
A = 1
NS = 2
MD = 3
MF = 4
CNAME = 5
SOA = 6
MB = 7
MG = 8
MR = 9
NULL = 10
WKS = 11
PTR = 12
HINFO = 13
MINFO = 14
MX = 15
TXT = 16
RP = 17
AFSDB = 18
X25 = 19
ISDN = 20
RT = 21
NSAP = 22
NSAP_PTR = 23
SIG = 24
KEY = 25
PX = 26
GPOS = 27
AAAA = 28
LOC = 29
NXT = 30
SRV = 33
NAPTR = 35
KX = 36
CERT = 37
A6 = 38
DNAME = 39
OPT = 41
APL = 42
DS = 43
SSHFP = 44
IPSECKEY = 45
RRSIG = 46
NSEC = 47
DNSKEY = 48
DHCID = 49
NSEC3 = 50
NSEC3PARAM = 51
TLSA = 52
HIP = 55
NINFO = 56
CDS = 59
CDNSKEY = 60
OPENPGPKEY = 61
CSYNC = 62
SPF = 99
UNSPEC = 103
EUI48 = 108
EUI64 = 109
TKEY = 249
TSIG = 250
IXFR = 251
AXFR = 252
MAILB = 253
MAILA = 254
ANY = 255
URI = 256
CAA = 257
AVC = 258
AMTRELAY = 259
TA = 32768
DLV = 32769
@classmethod
def _maximum(cls):
return 65535
@classmethod
def _short_name(cls):
return "type"
@classmethod
def _prefix(cls):
return "TYPE"
@classmethod
def _unknown_exception_class(cls):
return UnknownRdatatype
_registered_by_text = {}
_registered_by_value = {}
globals().update(RdataType.__members__)
_metatypes = {RdataType.OPT}
_singletons = {RdataType.SOA, RdataType.NXT, RdataType.DNAME,
RdataType.NSEC, RdataType.CNAME}
class UnknownRdatatype(dns.exception.DNSException):
"""DNS resource record type is unknown."""
def from_text(text):
"""Convert text into a DNS rdata type value.
The input text can be a defined DNS RR type mnemonic or
instance of the DNS generic type syntax.
For example, "NS" and "TYPE2" will both result in a value of 2.
Raises ``dns.rdatatype.UnknownRdatatype`` if the type is unknown.
Raises ``ValueError`` if the rdata type value is not >= 0 and <= 65535.
Returns an ``int``.
"""
text = text.upper().replace('-', '_')
try:
return RdataType.from_text(text)
except UnknownRdatatype:
registered_type = _registered_by_text.get(text)
if registered_type:
return registered_type
raise
def to_text(value):
"""Convert a DNS rdata type value to text.
If the value has a known mnemonic, it will be used, otherwise the
DNS generic type syntax will be used.
Raises ``ValueError`` if the rdata type value is not >= 0 and <= 65535.
Returns a ``str``.
"""
text = RdataType.to_text(value)
if text.startswith("TYPE"):
registered_text = _registered_by_value.get(value)
if registered_text:
text = registered_text
return text.replace('_', '-')
def is_metatype(rdtype):
"""True if the specified type is a metatype.
*rdtype* is an ``int``.
The currently defined metatypes are TKEY, TSIG, IXFR, AXFR, MAILA,
MAILB, ANY, and OPT.
Returns a ``bool``.
"""
return (256 > rdtype >= 128) or rdtype in _metatypes
def is_singleton(rdtype):
"""Is the specified type a singleton type?
Singleton types can only have a single rdata in an rdataset, or a single
RR in an RRset.
The currently defined singleton types are CNAME, DNAME, NSEC, NXT, and
SOA.
*rdtype* is an ``int``.
Returns a ``bool``.
"""
if rdtype in _singletons:
return True
return False
# pylint: disable=redefined-outer-name
def register_type(rdtype, rdtype_text, is_singleton=False):
"""Dynamically register an rdatatype.
*rdtype*, an ``int``, the rdatatype to register.
*rdtype_text*, a ``str``, the textual form of the rdatatype.
*is_singleton*, a ``bool``, indicating if the type is a singleton (i.e.
RRsets of the type can have only one member.)
"""
_registered_by_text[rdtype_text] = rdtype
_registered_by_value[rdtype] = rdtype_text
if is_singleton:
_singletons.add(rdtype)