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# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license
# Copyright (C) 2003-2007, 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 socket
import struct
import dns.ipv4
import dns.rdata
_proto_tcp = socket.getprotobyname('tcp')
_proto_udp = socket.getprotobyname('udp')
class WKS(dns.rdata.Rdata):
"""WKS record"""
# see: RFC 1035
__slots__ = ['address', 'protocol', 'bitmap']
def __init__(self, rdclass, rdtype, address, protocol, bitmap):
super().__init__(rdclass, rdtype)
object.__setattr__(self, 'address', address)
object.__setattr__(self, 'protocol', protocol)
object.__setattr__(self, 'bitmap', dns.rdata._constify(bitmap))
def to_text(self, origin=None, relativize=True, **kw):
bits = []
for i in range(0, len(self.bitmap)):
byte = self.bitmap[i]
for j in range(0, 8):
if byte & (0x80 >> j):
bits.append(str(i * 8 + j))
text = ' '.join(bits)
return '%s %d %s' % (self.address, self.protocol, text)
@classmethod
def from_text(cls, rdclass, rdtype, tok, origin=None, relativize=True,
relativize_to=None):
address = tok.get_string()
protocol = tok.get_string()
if protocol.isdigit():
protocol = int(protocol)
else:
protocol = socket.getprotobyname(protocol)
bitmap = bytearray()
while 1:
token = tok.get().unescape()
if token.is_eol_or_eof():
break
if token.value.isdigit():
serv = int(token.value)
else:
if protocol != _proto_udp and protocol != _proto_tcp:
raise NotImplementedError("protocol must be TCP or UDP")
if protocol == _proto_udp:
protocol_text = "udp"
else:
protocol_text = "tcp"
serv = socket.getservbyname(token.value, protocol_text)
i = serv // 8
l = len(bitmap)
if l < i + 1:
for j in range(l, i + 1):
bitmap.append(0)
bitmap[i] = bitmap[i] | (0x80 >> (serv % 8))
bitmap = dns.rdata._truncate_bitmap(bitmap)
return cls(rdclass, rdtype, address, protocol, bitmap)
def _to_wire(self, file, compress=None, origin=None, canonicalize=False):
file.write(dns.ipv4.inet_aton(self.address))
protocol = struct.pack('!B', self.protocol)
file.write(protocol)
file.write(self.bitmap)
@classmethod
def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin=None):
address = dns.ipv4.inet_ntoa(wire[current: current + 4])
protocol, = struct.unpack('!B', wire[current + 4: current + 5])
current += 5
rdlen -= 5
bitmap = wire[current: current + rdlen].unwrap()
return cls(rdclass, rdtype, address, protocol, bitmap)
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