1# Copyright (C) 2003-2007, 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 dns.exception 17import dns.rdata 18import dns.rdatatype 19import dns.name 20 21class NXT(dns.rdata.Rdata): 22 """NXT record 23 24 @ivar next: the next name 25 @type next: dns.name.Name object 26 @ivar bitmap: the type bitmap 27 @type bitmap: string 28 @see: RFC 2535""" 29 30 __slots__ = ['next', 'bitmap'] 31 32 def __init__(self, rdclass, rdtype, next, bitmap): 33 super(NXT, self).__init__(rdclass, rdtype) 34 self.next = next 35 self.bitmap = bitmap 36 37 def to_text(self, origin=None, relativize=True, **kw): 38 next = self.next.choose_relativity(origin, relativize) 39 bits = [] 40 for i in xrange(0, len(self.bitmap)): 41 byte = ord(self.bitmap[i]) 42 for j in xrange(0, 8): 43 if byte & (0x80 >> j): 44 bits.append(dns.rdatatype.to_text(i * 8 + j)) 45 text = ' '.join(bits) 46 return '%s %s' % (next, text) 47 48 def from_text(cls, rdclass, rdtype, tok, origin = None, relativize = True): 49 next = tok.get_name() 50 next = next.choose_relativity(origin, relativize) 51 bitmap = ['\x00', '\x00', '\x00', '\x00', 52 '\x00', '\x00', '\x00', '\x00', 53 '\x00', '\x00', '\x00', '\x00', 54 '\x00', '\x00', '\x00', '\x00' ] 55 while 1: 56 token = tok.get().unescape() 57 if token.is_eol_or_eof(): 58 break 59 if token.value.isdigit(): 60 nrdtype = int(token.value) 61 else: 62 nrdtype = dns.rdatatype.from_text(token.value) 63 if nrdtype == 0: 64 raise dns.exception.SyntaxError("NXT with bit 0") 65 if nrdtype > 127: 66 raise dns.exception.SyntaxError("NXT with bit > 127") 67 i = nrdtype // 8 68 bitmap[i] = chr(ord(bitmap[i]) | (0x80 >> (nrdtype % 8))) 69 bitmap = dns.rdata._truncate_bitmap(bitmap) 70 return cls(rdclass, rdtype, next, bitmap) 71 72 from_text = classmethod(from_text) 73 74 def to_wire(self, file, compress = None, origin = None): 75 self.next.to_wire(file, None, origin) 76 file.write(self.bitmap) 77 78 def to_digestable(self, origin = None): 79 return self.next.to_digestable(origin) + self.bitmap 80 81 def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin = None): 82 (next, cused) = dns.name.from_wire(wire[: current + rdlen], current) 83 current += cused 84 rdlen -= cused 85 bitmap = wire[current : current + rdlen] 86 if not origin is None: 87 next = next.relativize(origin) 88 return cls(rdclass, rdtype, next, bitmap) 89 90 from_wire = classmethod(from_wire) 91 92 def choose_relativity(self, origin = None, relativize = True): 93 self.next = self.next.choose_relativity(origin, relativize) 94 95 def _cmp(self, other): 96 v = cmp(self.next, other.next) 97 if v == 0: 98 v = cmp(self.bitmap, other.bitmap) 99 return v 100