# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license
# Copyright (C) 2004-2007, 2009-2011 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 binascii
import struct
import dns.exception
import dns.immutable
import dns.rdata
@dns.immutable.immutable
class NSEC3PARAM(dns.rdata.Rdata):
"""NSEC3PARAM record"""
__slots__ = ["algorithm", "flags", "iterations", "salt"]
def __init__(self, rdclass, rdtype, algorithm, flags, iterations, salt):
super().__init__(rdclass, rdtype)
self.algorithm = self._as_uint8(algorithm)
self.flags = self._as_uint8(flags)
self.iterations = self._as_uint16(iterations)
self.salt = self._as_bytes(salt, True, 255)
def to_text(self, origin=None, relativize=True, **kw):
if self.salt == b"":
salt = "-"
else:
salt = binascii.hexlify(self.salt).decode()
return "%u %u %u %s" % (self.algorithm, self.flags, self.iterations, salt)
@classmethod
def from_text(
cls, rdclass, rdtype, tok, origin=None, relativize=True, relativize_to=None
):
algorithm = tok.get_uint8()
flags = tok.get_uint8()
iterations = tok.get_uint16()
salt = tok.get_string()
if salt == "-":
salt = ""
else:
salt = binascii.unhexlify(salt.encode())
return cls(rdclass, rdtype, algorithm, flags, iterations, salt)
def _to_wire(self, file, compress=None, origin=None, canonicalize=False):
l = len(self.salt)
file.write(struct.pack("!BBHB", self.algorithm, self.flags, self.iterations, l))
file.write(self.salt)
@classmethod
def from_wire_parser(cls, rdclass, rdtype, parser, origin=None):
(algorithm, flags, iterations) = parser.get_struct("!BBH")
salt = parser.get_counted_bytes()
return cls(rdclass, rdtype, algorithm, flags, iterations, salt)
