Source code for pytomo.dns.rdtypes.dsbase

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from __future__ import absolute_import

import struct

from .. import rdata as dns_rdata
#from . import rdatatype as dns_rdatatype
from .. import exception as dns_exception

[docs]class DSBase(dns_rdata.Rdata): """Base class for rdata that is like a DS record @ivar key_tag: the key tag @type key_tag: int @ivar algorithm: the algorithm @type algorithm: int @ivar digest_type: the digest type @type digest_type: int @ivar digest: the digest @type digest: int @see: draft-ietf-dnsext-delegation-signer-14.txt""" __slots__ = ['key_tag', 'algorithm', 'digest_type', 'digest'] def __init__(self, rdclass, rdtype, key_tag, algorithm, digest_type, digest): super(DSBase, self).__init__(rdclass, rdtype) self.key_tag = key_tag self.algorithm = algorithm self.digest_type = digest_type self.digest = digest
[docs] def to_text(self, origin=None, relativize=True, **kw): return '%d %d %d %s' % (self.key_tag, self.algorithm, self.digest_type, dns_rdata._hexify(self.digest, chunksize=128))
[docs] def from_text(cls, rdclass, rdtype, tok, origin = None, relativize = True): key_tag = tok.get_uint16() algorithm = tok.get_uint8() digest_type = tok.get_uint8() 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) digest = ''.join(chunks) digest = digest.decode('hex_codec') return cls(rdclass, rdtype, key_tag, algorithm, digest_type, digest)
from_text = classmethod(from_text)
[docs] def to_wire(self, file, compress = None, origin = None): header = struct.pack("!HBB", self.key_tag, self.algorithm, self.digest_type) file.write(header) file.write(self.digest)
[docs] def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin = None): header = struct.unpack("!HBB", wire[current : current + 4]) current += 4 rdlen -= 4 digest = wire[current : current + rdlen] return cls(rdclass, rdtype, header[0], header[1], header[2], digest)
from_wire = classmethod(from_wire) def _cmp(self, other): hs = struct.pack("!HBB", self.key_tag, self.algorithm, self.digest_type) ho = struct.pack("!HBB", other.key_tag, other.algorithm, other.digest_type) v = cmp(hs, ho) if v == 0: v = cmp(self.digest, other.digest) return v