You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
137 lines
4.3 KiB
137 lines
4.3 KiB
# Copyright (C) 2004-2007, 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 base64
|
|
import struct
|
|
|
|
import dns.exception
|
|
import dns.dnssec
|
|
import dns.rdata
|
|
|
|
# wildcard import
|
|
__all__ = ["SEP", "REVOKE", "ZONE",
|
|
"flags_to_text_set", "flags_from_text_set"]
|
|
|
|
# flag constants
|
|
SEP = 0x0001
|
|
REVOKE = 0x0080
|
|
ZONE = 0x0100
|
|
|
|
_flag_by_text = {
|
|
'SEP': SEP,
|
|
'REVOKE': REVOKE,
|
|
'ZONE': ZONE
|
|
}
|
|
|
|
# We construct the inverse mapping programmatically to ensure that we
|
|
# cannot make any mistakes (e.g. omissions, cut-and-paste errors) that
|
|
# would cause the mapping not to be true inverse.
|
|
_flag_by_value = dict((y, x) for x, y in _flag_by_text.items())
|
|
|
|
|
|
def flags_to_text_set(flags):
|
|
"""Convert a DNSKEY flags value to set texts
|
|
@rtype: set([string])"""
|
|
|
|
flags_set = set()
|
|
mask = 0x1
|
|
while mask <= 0x8000:
|
|
if flags & mask:
|
|
text = _flag_by_value.get(mask)
|
|
if not text:
|
|
text = hex(mask)
|
|
flags_set.add(text)
|
|
mask <<= 1
|
|
return flags_set
|
|
|
|
|
|
def flags_from_text_set(texts_set):
|
|
"""Convert set of DNSKEY flag mnemonic texts to DNSKEY flag value
|
|
@rtype: int"""
|
|
|
|
flags = 0
|
|
for text in texts_set:
|
|
try:
|
|
flags += _flag_by_text[text]
|
|
except KeyError:
|
|
raise NotImplementedError(
|
|
"DNSKEY flag '%s' is not supported" % text)
|
|
return flags
|
|
|
|
|
|
class DNSKEYBase(dns.rdata.Rdata):
|
|
|
|
"""Base class for rdata that is like a DNSKEY record
|
|
|
|
@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(DNSKEYBase, self).__init__(rdclass, rdtype)
|
|
self.flags = flags
|
|
self.protocol = protocol
|
|
self.algorithm = algorithm
|
|
self.key = key
|
|
|
|
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))
|
|
|
|
@classmethod
|
|
def from_text(cls, rdclass, rdtype, tok, origin=None, relativize=True):
|
|
flags = tok.get_uint16()
|
|
protocol = tok.get_uint8()
|
|
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.encode())
|
|
b64 = b''.join(chunks)
|
|
key = base64.b64decode(b64)
|
|
return cls(rdclass, rdtype, flags, protocol, algorithm, key)
|
|
|
|
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)
|
|
|
|
@classmethod
|
|
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].unwrap()
|
|
return cls(rdclass, rdtype, header[0], header[1], header[2],
|
|
key)
|
|
|
|
def flags_to_text_set(self):
|
|
"""Convert a DNSKEY flags value to set texts
|
|
@rtype: set([string])"""
|
|
return flags_to_text_set(self.flags)
|