1 # Copyright (C) 2010 Nominum, Inc.
3 # Permission to use, copy, modify, and distribute this software and its
4 # documentation for any purpose with or without fee is hereby granted,
5 # provided that the above copyright notice and this permission notice
6 # appear in all copies.
8 # THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES
9 # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR
11 # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
14 # OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21 class DSBase(dns.rdata.Rdata):
22 """Base class for rdata that is like a DS record
24 @ivar key_tag: the key tag
26 @ivar algorithm: the algorithm
28 @ivar digest_type: the digest type
29 @type digest_type: int
30 @ivar digest: the digest
32 @see: draft-ietf-dnsext-delegation-signer-14.txt"""
34 __slots__ = ['key_tag', 'algorithm', 'digest_type', 'digest']
36 def __init__(self, rdclass, rdtype, key_tag, algorithm, digest_type,
38 super(DSBase, self).__init__(rdclass, rdtype)
39 self.key_tag = key_tag
40 self.algorithm = algorithm
41 self.digest_type = digest_type
44 def to_text(self, origin=None, relativize=True, **kw):
45 return '%d %d %d %s' % (self.key_tag, self.algorithm,
47 dns.rdata._hexify(self.digest,
50 def from_text(cls, rdclass, rdtype, tok, origin = None, relativize = True):
51 key_tag = tok.get_uint16()
52 algorithm = tok.get_uint8()
53 digest_type = tok.get_uint8()
56 t = tok.get().unescape()
59 if not t.is_identifier():
60 raise dns.exception.SyntaxError
61 chunks.append(t.value)
62 digest = ''.join(chunks)
63 digest = digest.decode('hex_codec')
64 return cls(rdclass, rdtype, key_tag, algorithm, digest_type,
67 from_text = classmethod(from_text)
69 def to_wire(self, file, compress = None, origin = None):
70 header = struct.pack("!HBB", self.key_tag, self.algorithm,
73 file.write(self.digest)
75 def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin = None):
76 header = struct.unpack("!HBB", wire[current : current + 4])
79 digest = wire[current : current + rdlen]
80 return cls(rdclass, rdtype, header[0], header[1], header[2], digest)
82 from_wire = classmethod(from_wire)
84 def _cmp(self, other):
85 hs = struct.pack("!HBB", self.key_tag, self.algorithm,
87 ho = struct.pack("!HBB", other.key_tag, other.algorithm,
91 v = cmp(self.digest, other.digest)