Source code for pytomo.dns.rdtypes.keybase

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from __future__ import absolute_import

import struct

from .. import exception as dns_exception
from .. import dnssec as dns_dnssec
from .. import rdata as dns_rdata

_flags_from_text = {
    'NOCONF': (0x4000, 0xC000),
    'NOAUTH': (0x8000, 0xC000),
    'NOKEY': (0xC000, 0xC000),
    'FLAG2': (0x2000, 0x2000),
    'EXTEND': (0x1000, 0x1000),
    'FLAG4': (0x0800, 0x0800),
    'FLAG5': (0x0400, 0x0400),
    'USER': (0x0000, 0x0300),
    'ZONE': (0x0100, 0x0300),
    'HOST': (0x0200, 0x0300),
    'NTYP3': (0x0300, 0x0300),
    'FLAG8': (0x0080, 0x0080),
    'FLAG9': (0x0040, 0x0040),
    'FLAG10': (0x0020, 0x0020),
    'FLAG11': (0x0010, 0x0010),
    'SIG0': (0x0000, 0x000f),
    'SIG1': (0x0001, 0x000f),
    'SIG2': (0x0002, 0x000f),
    'SIG3': (0x0003, 0x000f),
    'SIG4': (0x0004, 0x000f),
    'SIG5': (0x0005, 0x000f),
    'SIG6': (0x0006, 0x000f),
    'SIG7': (0x0007, 0x000f),
    'SIG8': (0x0008, 0x000f),
    'SIG9': (0x0009, 0x000f),
    'SIG10': (0x000a, 0x000f),
    'SIG11': (0x000b, 0x000f),
    'SIG12': (0x000c, 0x000f),
    'SIG13': (0x000d, 0x000f),
    'SIG14': (0x000e, 0x000f),
    'SIG15': (0x000f, 0x000f),
    }

_protocol_from_text = {
    'NONE' : 0,
    'TLS' : 1,
    'EMAIL' : 2,
    'DNSSEC' : 3,
    'IPSEC' : 4,
    'ALL' : 255,
    }

[docs]class KEYBase(dns_rdata.Rdata): """KEY-like record base @ivar flags: the key flags @type flags: int @ivar protocol: the protocol for which this key may be used @type protocol: int @ivar algorithm: the algorithm used for the key @type algorithm: int @ivar key: the public key @type key: string""" __slots__ = ['flags', 'protocol', 'algorithm', 'key'] def __init__(self, rdclass, rdtype, flags, protocol, algorithm, key): super(KEYBase, self).__init__(rdclass, rdtype) self.flags = flags self.protocol = protocol self.algorithm = algorithm self.key = key
[docs] def to_text(self, origin=None, relativize=True, **kw): return '%d %d %d %s' % (self.flags, self.protocol, self.algorithm, dns_rdata._base64ify(self.key))
[docs] def from_text(cls, rdclass, rdtype, tok, origin = None, relativize = True): flags = tok.get_string() if flags.isdigit(): flags = int(flags) else: flag_names = flags.split('|') flags = 0 for flag in flag_names: v = _flags_from_text.get(flag) if v is None: raise dns_exception.SyntaxError('unknown flag %s' % flag) flags &= ~v[1] flags |= v[0] protocol = tok.get_string() if protocol.isdigit(): protocol = int(protocol) else: protocol = _protocol_from_text.get(protocol) if protocol is None: raise dns_exception.SyntaxError('unknown protocol %s' % protocol) algorithm = dns_dnssec.algorithm_from_text(tok.get_string()) chunks = [] while 1: t = tok.get().unescape() if t.is_eol_or_eof(): break if not t.is_identifier(): raise dns_exception.SyntaxError chunks.append(t.value) b64 = ''.join(chunks) key = b64.decode('base64_codec') return cls(rdclass, rdtype, flags, protocol, algorithm, key)
from_text = classmethod(from_text)
[docs] def to_wire(self, file, compress = None, origin = None): header = struct.pack("!HBB", self.flags, self.protocol, self.algorithm) file.write(header) file.write(self.key)
[docs] def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin = None): if rdlen < 4: raise dns_exception.FormError header = struct.unpack('!HBB', wire[current : current + 4]) current += 4 rdlen -= 4 key = wire[current : current + rdlen] return cls(rdclass, rdtype, header[0], header[1], header[2], key)
from_wire = classmethod(from_wire) def _cmp(self, other): hs = struct.pack("!HBB", self.flags, self.protocol, self.algorithm) ho = struct.pack("!HBB", other.flags, other.protocol, other.algorithm) v = cmp(hs, ho) if v == 0: v = cmp(self.key, other.key) return v