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16 import cStringIO
17 import string
18 import struct
19
20 import dns.exception
21 import dns.rdata
22 import dns.rdatatype
23
24 -class HIP(dns.rdata.Rdata):
25 """HIP record
26
27 @ivar hit: the host identity tag
28 @type hit: string
29 @ivar algorithm: the public key cryptographic algorithm
30 @type algorithm: int
31 @ivar key: the public key
32 @type key: string
33 @ivar servers: the rendezvous servers
34 @type servers: list of dns.name.Name objects
35 @see: RFC 5205"""
36
37 __slots__ = ['hit', 'algorithm', 'key', 'servers']
38
39 - def __init__(self, rdclass, rdtype, hit, algorithm, key, servers):
45
46 - def to_text(self, origin=None, relativize=True, **kw):
47 hit = self.hit.encode('hex-codec')
48 key = self.key.encode('base64-codec').replace('\n', '')
49 text = ''
50 servers = []
51 for server in self.servers:
52 servers.append(str(server.choose_relativity(origin, relativize)))
53 if len(servers) > 0:
54 text += (' ' + ' '.join(servers))
55 return '%u %s %s%s' % (self.algorithm, hit, key, text)
56
57 - def from_text(cls, rdclass, rdtype, tok, origin = None, relativize = True):
58 algorithm = tok.get_uint8()
59 hit = tok.get_string().decode('hex-codec')
60 if len(hit) > 255:
61 raise dns.exception.SyntaxError("HIT too long")
62 key = tok.get_string().decode('base64-codec')
63 servers = []
64 while 1:
65 token = tok.get()
66 if token.is_eol_or_eof():
67 break
68 server = dns.name.from_text(token.value, origin)
69 server.choose_relativity(origin, relativize)
70 servers.append(server)
71 return cls(rdclass, rdtype, hit, algorithm, key, servers)
72
73 from_text = classmethod(from_text)
74
75 - def to_wire(self, file, compress = None, origin = None):
76 lh = len(self.hit)
77 lk = len(self.key)
78 file.write(struct.pack("!BBH", lh, self.algorithm, lk))
79 file.write(self.hit)
80 file.write(self.key)
81 for server in self.servers:
82 server.to_wire(file, None, origin)
83
84 - def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin = None):
85 (lh, algorithm, lk) = struct.unpack('!BBH',
86 wire[current : current + 4])
87 current += 4
88 rdlen -= 4
89 hit = wire[current : current + lh].unwrap()
90 current += lh
91 rdlen -= lh
92 key = wire[current : current + lk].unwrap()
93 current += lk
94 rdlen -= lk
95 servers = []
96 while rdlen > 0:
97 (server, cused) = dns.name.from_wire(wire[: current + rdlen],
98 current)
99 current += cused
100 rdlen -= cused
101 if not origin is None:
102 server = server.relativize(origin)
103 servers.append(server)
104 return cls(rdclass, rdtype, hit, algorithm, key, servers)
105
106 from_wire = classmethod(from_wire)
107
114
115 - def _cmp(self, other):
116 b1 = cStringIO.StringIO()
117 lh = len(self.hit)
118 lk = len(self.key)
119 b1.write(struct.pack("!BBH", lh, self.algorithm, lk))
120 b1.write(self.hit)
121 b1.write(self.key)
122 b2 = cStringIO.StringIO()
123 lh = len(other.hit)
124 lk = len(other.key)
125 b2.write(struct.pack("!BBH", lh, other.algorithm, lk))
126 b2.write(other.hit)
127 b2.write(other.key)
128 v = cmp(b1.getvalue(), b2.getvalue())
129 if v != 0:
130 return v
131 ls = len(self.servers)
132 lo = len(other.servers)
133 count = min(ls, lo)
134 i = 0
135 while i < count:
136 v = cmp(self.servers[i], other.servers[i])
137 if v != 0:
138 return v
139 i += 1
140 return ls - lo
141