Source Code for Module dns.rdtypes.ANY.HIP

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 15   
 16  import struct 
 17  import base64 
 18  import binascii 
 19   
 20  import dns.exception 
 21  import dns.rdata 
 22  import dns.rdatatype 
 23   
 24   
 25 -class HIP(dns.rdata.Rdata): 
 26   
 27      """HIP record 
 28   
 29      @ivar hit: the host identity tag 
 30      @type hit: string 
 31      @ivar algorithm: the public key cryptographic algorithm 
 32      @type algorithm: int 
 33      @ivar key: the public key 
 34      @type key: string 
 35      @ivar servers: the rendezvous servers 
 36      @type servers: list of dns.name.Name objects 
 37      @see: RFC 5205""" 
 38   
 39      __slots__ = ['hit', 'algorithm', 'key', 'servers'] 
 40   
 41 -    def __init__(self, rdclass, rdtype, hit, algorithm, key, servers): 
 42          super(HIP, self).__init__(rdclass, rdtype) 
 43          self.hit = hit 
 44          self.algorithm = algorithm 
 45          self.key = key 
 46          self.servers = servers 
 47   
 48 -    def to_text(self, origin=None, relativize=True, **kw): 
 49          hit = binascii.hexlify(self.hit).decode() 
 50          key = base64.b64encode(self.key).replace(b'\n', b'').decode() 
 51          text = u'' 
 52          servers = [] 
 53          for server in self.servers: 
 54              servers.append(server.choose_relativity(origin, relativize)) 
 55          if len(servers) > 0: 
 56              text += (u' ' + u' '.join((x.to_unicode() for x in servers))) 
 57          return u'%u %s %s%s' % (self.algorithm, hit, key, text) 
 58   
 59      @classmethod 
 60 -    def from_text(cls, rdclass, rdtype, tok, origin=None, relativize=True): 
 61          algorithm = tok.get_uint8() 
 62          hit = binascii.unhexlify(tok.get_string().encode()) 
 63          if len(hit) > 255: 
 64              raise dns.exception.SyntaxError("HIT too long") 
 65          key = base64.b64decode(tok.get_string().encode()) 
 66          servers = [] 
 67          while 1: 
 68              token = tok.get() 
 69              if token.is_eol_or_eof(): 
 70                  break 
 71              server = dns.name.from_text(token.value, origin) 
 72              server.choose_relativity(origin, relativize) 
 73              servers.append(server) 
 74          return cls(rdclass, rdtype, hit, algorithm, key, servers) 
 75   
 76 -    def to_wire(self, file, compress=None, origin=None): 
 77          lh = len(self.hit) 
 78          lk = len(self.key) 
 79          file.write(struct.pack("!BBH", lh, self.algorithm, lk)) 
 80          file.write(self.hit) 
 81          file.write(self.key) 
 82          for server in self.servers: 
 83              server.to_wire(file, None, origin) 
 84   
 85      @classmethod 
 86 -    def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin=None): 
 87          (lh, algorithm, lk) = struct.unpack('!BBH', 
 88                                              wire[current: current + 4]) 
 89          current += 4 
 90          rdlen -= 4 
 91          hit = wire[current: current + lh].unwrap() 
 92          current += lh 
 93          rdlen -= lh 
 94          key = wire[current: current + lk].unwrap() 
 95          current += lk 
 96          rdlen -= lk 
 97          servers = [] 
 98          while rdlen > 0: 
 99              (server, cused) = dns.name.from_wire(wire[: current + rdlen], 
100                                                   current) 
101              current += cused 
102              rdlen -= cused 
103              if origin is not None: 
104                  server = server.relativize(origin) 
105              servers.append(server) 
106          return cls(rdclass, rdtype, hit, algorithm, key, servers) 
107   
108 -    def choose_relativity(self, origin=None, relativize=True): 
109          servers = [] 
110          for server in self.servers: 
111              server = server.choose_relativity(origin, relativize) 
112              servers.append(server) 
113          self.servers = servers 
114