Source code for pytomo.dns.rdtypes.IN.WKS

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from __future__ import absolute_import

import socket
import struct

from ... import ipv4 as dns_ipv4
from ... import rdata as dns_rdata

_proto_tcp = socket.getprotobyname('tcp')
_proto_udp = socket.getprotobyname('udp')

[docs]class WKS(dns_rdata.Rdata): """WKS record @ivar address: the address @type address: string @ivar protocol: the protocol @type protocol: int @ivar bitmap: the bitmap @type bitmap: string @see: RFC 1035""" __slots__ = ['address', 'protocol', 'bitmap'] def __init__(self, rdclass, rdtype, address, protocol, bitmap): super(WKS, self).__init__(rdclass, rdtype) self.address = address self.protocol = protocol self.bitmap = bitmap
[docs] def to_text(self, origin=None, relativize=True, **kw): bits = [] for i in xrange(0, len(self.bitmap)): byte = ord(self.bitmap[i]) for j in xrange(0, 8): if byte & (0x80 >> j): bits.append(str(i * 8 + j)) text = ' '.join(bits) return '%s %d %s' % (self.address, self.protocol, text)
[docs] def from_text(cls, rdclass, rdtype, tok, origin = None, relativize = True): address = tok.get_string() protocol = tok.get_string() if protocol.isdigit(): protocol = int(protocol) else: protocol = socket.getprotobyname(protocol) bitmap = [] 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 xrange(l, i + 1): bitmap.append('\x00') bitmap[i] = chr(ord(bitmap[i]) | (0x80 >> (serv % 8))) bitmap = dns_rdata._truncate_bitmap(bitmap) return cls(rdclass, rdtype, address, protocol, bitmap)
from_text = classmethod(from_text)
[docs] def to_wire(self, file, compress = None, origin = None): file.write(dns_ipv4.inet_aton(self.address)) protocol = struct.pack('!B', self.protocol) file.write(protocol) file.write(self.bitmap)
[docs] 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] return cls(rdclass, rdtype, address, protocol, bitmap)
from_wire = classmethod(from_wire) def _cmp(self, other): sa = dns_ipv4.inet_aton(self.address) oa = dns_ipv4.inet_aton(other.address) v = cmp(sa, oa) if v == 0: sp = struct.pack('!B', self.protocol) op = struct.pack('!B', other.protocol) v = cmp(sp, op) if v == 0: v = cmp(self.bitmap, other.bitmap) return v