GIF89a;
Direktori : /lib64/python2.7/site-packages/dns/rdtypes/IN/ |
Current File : //lib64/python2.7/site-packages/dns/rdtypes/IN/APL.py |
# Copyright (C) 2003-2007, 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 cStringIO import struct import dns.exception import dns.inet import dns.rdata import dns.tokenizer class APLItem(object): """An APL list item. @ivar family: the address family (IANA address family registry) @type family: int @ivar negation: is this item negated? @type negation: bool @ivar address: the address @type address: string @ivar prefix: the prefix length @type prefix: int """ __slots__ = ['family', 'negation', 'address', 'prefix'] def __init__(self, family, negation, address, prefix): self.family = family self.negation = negation self.address = address self.prefix = prefix def __str__(self): if self.negation: return "!%d:%s/%s" % (self.family, self.address, self.prefix) else: return "%d:%s/%s" % (self.family, self.address, self.prefix) def to_wire(self, file): if self.family == 1: address = dns.inet.inet_pton(dns.inet.AF_INET, self.address) elif self.family == 2: address = dns.inet.inet_pton(dns.inet.AF_INET6, self.address) else: address = self.address.decode('hex_codec') # # Truncate least significant zero bytes. # last = 0 for i in xrange(len(address) - 1, -1, -1): if address[i] != chr(0): last = i + 1 break address = address[0 : last] l = len(address) assert l < 128 if self.negation: l |= 0x80 header = struct.pack('!HBB', self.family, self.prefix, l) file.write(header) file.write(address) class APL(dns.rdata.Rdata): """APL record. @ivar items: a list of APL items @type items: list of APL_Item @see: RFC 3123""" __slots__ = ['items'] def __init__(self, rdclass, rdtype, items): super(APL, self).__init__(rdclass, rdtype) self.items = items def to_text(self, origin=None, relativize=True, **kw): return ' '.join(map(lambda x: str(x), self.items)) def from_text(cls, rdclass, rdtype, tok, origin = None, relativize = True): items = [] while 1: token = tok.get().unescape() if token.is_eol_or_eof(): break item = token.value if item[0] == '!': negation = True item = item[1:] else: negation = False (family, rest) = item.split(':', 1) family = int(family) (address, prefix) = rest.split('/', 1) prefix = int(prefix) item = APLItem(family, negation, address, prefix) items.append(item) return cls(rdclass, rdtype, items) from_text = classmethod(from_text) def to_wire(self, file, compress = None, origin = None): for item in self.items: item.to_wire(file) def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin = None): items = [] while 1: if rdlen == 0: break if rdlen < 4: raise dns.exception.FormError header = struct.unpack('!HBB', wire[current : current + 4]) afdlen = header[2] if afdlen > 127: negation = True afdlen -= 128 else: negation = False current += 4 rdlen -= 4 if rdlen < afdlen: raise dns.exception.FormError address = wire[current : current + afdlen].unwrap() l = len(address) if header[0] == 1: if l < 4: address += '\x00' * (4 - l) address = dns.inet.inet_ntop(dns.inet.AF_INET, address) elif header[0] == 2: if l < 16: address += '\x00' * (16 - l) address = dns.inet.inet_ntop(dns.inet.AF_INET6, address) else: # # This isn't really right according to the RFC, but it # seems better than throwing an exception # address = address.encode('hex_codec') current += afdlen rdlen -= afdlen item = APLItem(header[0], negation, address, header[1]) items.append(item) return cls(rdclass, rdtype, items) from_wire = classmethod(from_wire) def _cmp(self, other): f = cStringIO.StringIO() self.to_wire(f) wire1 = f.getvalue() f.seek(0) f.truncate() other.to_wire(f) wire2 = f.getvalue() f.close() return cmp(wire1, wire2)