Source Code for Module dns.rdtypes.IN.WKS

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 15   
 16  import socket 
 17  import struct 
 18   
 19  import dns.ipv4 
 20  import dns.rdata 
 21  from dns._compat import xrange 
 22   
 23  _proto_tcp = socket.getprotobyname('tcp') 
 24  _proto_udp = socket.getprotobyname('udp') 
 25   
 26   
 27 -class WKS(dns.rdata.Rdata): 
 28   
 29      """WKS record 
 30   
 31      @ivar address: the address 
 32      @type address: string 
 33      @ivar protocol: the protocol 
 34      @type protocol: int 
 35      @ivar bitmap: the bitmap 
 36      @type bitmap: string 
 37      @see: RFC 1035""" 
 38   
 39      __slots__ = ['address', 'protocol', 'bitmap'] 
 40   
 41 -    def __init__(self, rdclass, rdtype, address, protocol, bitmap): 
 42          super(WKS, self).__init__(rdclass, rdtype) 
 43          self.address = address 
 44          self.protocol = protocol 
 45          if not isinstance(bitmap, bytearray): 
 46              self.bitmap = bytearray(bitmap) 
 47          else: 
 48              self.bitmap = bitmap 
 49   
 50 -    def to_text(self, origin=None, relativize=True, **kw): 
 51          bits = [] 
 52          for i in xrange(0, len(self.bitmap)): 
 53              byte = self.bitmap[i] 
 54              for j in xrange(0, 8): 
 55                  if byte & (0x80 >> j): 
 56                      bits.append(str(i * 8 + j)) 
 57          text = ' '.join(bits) 
 58          return '%s %d %s' % (self.address, self.protocol, text) 
 59   
 60      @classmethod 
 61 -    def from_text(cls, rdclass, rdtype, tok, origin=None, relativize=True): 
 62          address = tok.get_string() 
 63          protocol = tok.get_string() 
 64          if protocol.isdigit(): 
 65              protocol = int(protocol) 
 66          else: 
 67              protocol = socket.getprotobyname(protocol) 
 68          bitmap = bytearray() 
 69          while 1: 
 70              token = tok.get().unescape() 
 71              if token.is_eol_or_eof(): 
 72                  break 
 73              if token.value.isdigit(): 
 74                  serv = int(token.value) 
 75              else: 
 76                  if protocol != _proto_udp and protocol != _proto_tcp: 
 77                      raise NotImplementedError("protocol must be TCP or UDP") 
 78                  if protocol == _proto_udp: 
 79                      protocol_text = "udp" 
 80                  else: 
 81                      protocol_text = "tcp" 
 82                  serv = socket.getservbyname(token.value, protocol_text) 
 83              i = serv // 8 
 84              l = len(bitmap) 
 85              if l < i + 1: 
 86                  for j in xrange(l, i + 1): 
 87                      bitmap.append(0) 
 88              bitmap[i] = bitmap[i] | (0x80 >> (serv % 8)) 
 89          bitmap = dns.rdata._truncate_bitmap(bitmap) 
 90          return cls(rdclass, rdtype, address, protocol, bitmap) 
 91   
 92 -    def to_wire(self, file, compress=None, origin=None): 
 93          file.write(dns.ipv4.inet_aton(self.address)) 
 94          protocol = struct.pack('!B', self.protocol) 
 95          file.write(protocol) 
 96          file.write(self.bitmap) 
 97   
 98      @classmethod 
 99 -    def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin=None): 
100          address = dns.ipv4.inet_ntoa(wire[current: current + 4]) 
101          protocol, = struct.unpack('!B', wire[current + 4: current + 5]) 
102          current += 5 
103          rdlen -= 5 
104          bitmap = wire[current: current + rdlen].unwrap() 
105          return cls(rdclass, rdtype, address, protocol, bitmap) 
106