1# Copyright (C) 2004-2007, 2009, 2010 Nominum, Inc. 2# 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. 7# 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. 15 16import cStringIO 17import struct 18 19import dns.exception 20import dns.rdata 21 22class NSEC3PARAM(dns.rdata.Rdata): 23 """NSEC3PARAM record 24 25 @ivar algorithm: the hash algorithm number 26 @type algorithm: int 27 @ivar flags: the flags 28 @type flags: int 29 @ivar iterations: the number of iterations 30 @type iterations: int 31 @ivar salt: the salt 32 @type salt: string""" 33 34 __slots__ = ['algorithm', 'flags', 'iterations', 'salt'] 35 36 def __init__(self, rdclass, rdtype, algorithm, flags, iterations, salt): 37 super(NSEC3PARAM, self).__init__(rdclass, rdtype) 38 self.algorithm = algorithm 39 self.flags = flags 40 self.iterations = iterations 41 self.salt = salt 42 43 def to_text(self, origin=None, relativize=True, **kw): 44 if self.salt == '': 45 salt = '-' 46 else: 47 salt = self.salt.encode('hex-codec') 48 return '%u %u %u %s' % (self.algorithm, self.flags, self.iterations, salt) 49 50 def from_text(cls, rdclass, rdtype, tok, origin = None, relativize = True): 51 algorithm = tok.get_uint8() 52 flags = tok.get_uint8() 53 iterations = tok.get_uint16() 54 salt = tok.get_string() 55 if salt == '-': 56 salt = '' 57 else: 58 salt = salt.decode('hex-codec') 59 return cls(rdclass, rdtype, algorithm, flags, iterations, salt) 60 61 from_text = classmethod(from_text) 62 63 def to_wire(self, file, compress = None, origin = None): 64 l = len(self.salt) 65 file.write(struct.pack("!BBHB", self.algorithm, self.flags, 66 self.iterations, l)) 67 file.write(self.salt) 68 69 def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin = None): 70 (algorithm, flags, iterations, slen) = struct.unpack('!BBHB', 71 wire[current : current + 5]) 72 current += 5 73 rdlen -= 5 74 salt = wire[current : current + slen] 75 current += slen 76 rdlen -= slen 77 if rdlen != 0: 78 raise dns.exception.FormError 79 return cls(rdclass, rdtype, algorithm, flags, iterations, salt) 80 81 from_wire = classmethod(from_wire) 82 83 def _cmp(self, other): 84 b1 = cStringIO.StringIO() 85 self.to_wire(b1) 86 b2 = cStringIO.StringIO() 87 other.to_wire(b2) 88 return cmp(b1.getvalue(), b2.getvalue()) 89