Source Code for Module dns.rdtypes.ANY.CAA

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15   
16  import struct 
17   
18  import dns.exception 
19  import dns.rdata 
20  import dns.tokenizer 
21   
22   
23 -class CAA(dns.rdata.Rdata): 
24   
25      """CAA (Certification Authority Authorization) record 
26   
27      @ivar flags: the flags 
28      @type flags: int 
29      @ivar tag: the tag 
30      @type tag: string 
31      @ivar value: the value 
32      @type value: string 
33      @see: RFC 6844""" 
34   
35      __slots__ = ['flags', 'tag', 'value'] 
36   
37 -    def __init__(self, rdclass, rdtype, flags, tag, value): 
38          super(CAA, self).__init__(rdclass, rdtype) 
39          self.flags = flags 
40          self.tag = tag 
41          self.value = value 
42   
43 -    def to_text(self, origin=None, relativize=True, **kw): 
44          return '%u %s "%s"' % (self.flags, 
45                                 dns.rdata._escapify(self.tag), 
46                                 dns.rdata._escapify(self.value)) 
47   
48      @classmethod 
49 -    def from_text(cls, rdclass, rdtype, tok, origin=None, relativize=True): 
50          flags = tok.get_uint8() 
51          tag = tok.get_string().encode() 
52          if len(tag) > 255: 
53              raise dns.exception.SyntaxError("tag too long") 
54          if not tag.isalnum(): 
55              raise dns.exception.SyntaxError("tag is not alphanumeric") 
56          value = tok.get_string().encode() 
57          return cls(rdclass, rdtype, flags, tag, value) 
58   
59 -    def to_wire(self, file, compress=None, origin=None): 
60          file.write(struct.pack('!B', self.flags)) 
61          l = len(self.tag) 
62          assert l < 256 
63          file.write(struct.pack('!B', l)) 
64          file.write(self.tag) 
65          file.write(self.value) 
66   
67      @classmethod 
68 -    def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin=None): 
69          (flags, l) = struct.unpack('!BB', wire[current: current + 2]) 
70          current += 2 
71          tag = wire[current: current + l] 
72          value = wire[current + l:current + rdlen - 2] 
73          return cls(rdclass, rdtype, flags, tag, value) 
74