Source Code for Module dns.rdtypes.ANY.SSHFP

 1  # Copyright (C) 2005-2007, 2009-2011 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   
16  import struct 
17  import binascii 
18   
19  import dns.rdata 
20  import dns.rdatatype 
21   
22   
23 -class SSHFP(dns.rdata.Rdata): 
24   
25      """SSHFP record 
26   
27      @ivar algorithm: the algorithm 
28      @type algorithm: int 
29      @ivar fp_type: the digest type 
30      @type fp_type: int 
31      @ivar fingerprint: the fingerprint 
32      @type fingerprint: string 
33      @see: draft-ietf-secsh-dns-05.txt""" 
34   
35      __slots__ = ['algorithm', 'fp_type', 'fingerprint'] 
36   
37 -    def __init__(self, rdclass, rdtype, algorithm, fp_type, 
38                   fingerprint): 
39          super(SSHFP, self).__init__(rdclass, rdtype) 
40          self.algorithm = algorithm 
41          self.fp_type = fp_type 
42          self.fingerprint = fingerprint 
43   
44 -    def to_text(self, origin=None, relativize=True, **kw): 
45          return '%d %d %s' % (self.algorithm, 
46                               self.fp_type, 
47                               dns.rdata._hexify(self.fingerprint, 
48                                                 chunksize=128)) 
49   
50      @classmethod 
51 -    def from_text(cls, rdclass, rdtype, tok, origin=None, relativize=True): 
52          algorithm = tok.get_uint8() 
53          fp_type = tok.get_uint8() 
54          chunks = [] 
55          while 1: 
56              t = tok.get().unescape() 
57              if t.is_eol_or_eof(): 
58                  break 
59              if not t.is_identifier(): 
60                  raise dns.exception.SyntaxError 
61              chunks.append(t.value.encode()) 
62          fingerprint = b''.join(chunks) 
63          fingerprint = binascii.unhexlify(fingerprint) 
64          return cls(rdclass, rdtype, algorithm, fp_type, fingerprint) 
65   
66 -    def to_wire(self, file, compress=None, origin=None): 
67          header = struct.pack("!BB", self.algorithm, self.fp_type) 
68          file.write(header) 
69          file.write(self.fingerprint) 
70   
71      @classmethod 
72 -    def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin=None): 
73          header = struct.unpack("!BB", wire[current: current + 2]) 
74          current += 2 
75          rdlen -= 2 
76          fingerprint = wire[current: current + rdlen].unwrap() 
77          return cls(rdclass, rdtype, header[0], header[1], fingerprint) 
78