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# 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.
import struct
import dns.edns
import dns.immutable
import dns.exception
import dns.rdata
# We don't implement from_text, and that's ok.
# pylint: disable=abstract-method
@dns.immutable.immutable
class OPT(dns.rdata.Rdata):
"""OPT record"""
__slots__ = ['options']
def __init__(self, rdclass, rdtype, options):
"""Initialize an OPT rdata.
*rdclass*, an ``int`` is the rdataclass of the Rdata,
which is also the payload size.
*rdtype*, an ``int`` is the rdatatype of the Rdata.
*options*, a tuple of ``bytes``
"""
super().__init__(rdclass, rdtype)
for option in options:
if not isinstance(option, dns.edns.Option):
raise ValueError('option is not a dns.edns.option')
self.options = dns.rdata._constify(options)
def _to_wire(self, file, compress=None, origin=None, canonicalize=False):
for opt in self.options:
owire = opt.to_wire()
file.write(struct.pack("!HH", opt.otype, len(owire)))
file.write(owire)
def to_text(self, origin=None, relativize=True, **kw):
return ' '.join(opt.to_text() for opt in self.options)
@classmethod
def from_wire_parser(cls, rdclass, rdtype, parser, origin=None):
options = []
while parser.remaining() > 0:
(otype, olen) = parser.get_struct('!HH')
with parser.restrict_to(olen):
opt = dns.edns.option_from_wire_parser(otype, parser)
options.append(opt)
return cls(rdclass, rdtype, options)
@property
def payload(self):
"payload size"
return self.rdclass
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