1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
|
# -*- test-case-name: twisted.names.test.test_names -*-
# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.
from __future__ import absolute_import, division
__all__ = ['SecondaryAuthority', 'SecondaryAuthorityService']
from twisted.internet import task, defer
from twisted.names import dns
from twisted.names import common
from twisted.names import client
from twisted.names import resolve
from twisted.names.authority import FileAuthority
from twisted.python import log, failure
from twisted.python.compat import nativeString
from twisted.application import service
class SecondaryAuthorityService(service.Service):
"""
A service that keeps one or more authorities up to date by doing hourly
zone transfers from a master.
@ivar primary: IP address of the master.
@type primary: L{str}
@ivar domains: An authority for each domain mirrored from the master.
@type domains: L{list} of L{SecondaryAuthority}
"""
calls = None
_port = 53
def __init__(self, primary, domains):
"""
@param primary: The IP address of the server from which to perform
zone transfers.
@type primary: L{str}
@param domains: A sequence of domain names for which to perform
zone transfers.
@type domains: L{list} of L{bytes}
"""
self.primary = nativeString(primary)
self.domains = [SecondaryAuthority(primary, d) for d in domains]
@classmethod
def fromServerAddressAndDomains(cls, serverAddress, domains):
"""
Construct a new L{SecondaryAuthorityService} from a tuple giving a
server address and a C{str} giving the name of a domain for which this
is an authority.
@param serverAddress: A two-tuple, the first element of which is a
C{str} giving an IP address and the second element of which is a
C{int} giving a port number. Together, these define where zone
transfers will be attempted from.
@param domain: A C{bytes} giving the domain to transfer.
@return: A new instance of L{SecondaryAuthorityService}.
"""
primary, port = serverAddress
service = cls(primary, [])
service._port = port
service.domains = [
SecondaryAuthority.fromServerAddressAndDomain(serverAddress, d)
for d in domains]
return service
def getAuthority(self):
"""
Get a resolver for the transferred domains.
@rtype: L{ResolverChain}
"""
return resolve.ResolverChain(self.domains)
def startService(self):
service.Service.startService(self)
self.calls = [task.LoopingCall(d.transfer) for d in self.domains]
i = 0
from twisted.internet import reactor
for c in self.calls:
# XXX Add errbacks, respect proper timeouts
reactor.callLater(i, c.start, 60 * 60)
i += 1
def stopService(self):
service.Service.stopService(self)
for c in self.calls:
c.stop()
class SecondaryAuthority(FileAuthority):
"""
An Authority that keeps itself updated by performing zone transfers.
@ivar primary: The IP address of the server from which zone transfers will
be attempted.
@type primary: C{str}
@ivar _port: The port number of the server from which zone transfers will
be attempted.
@type: C{int}
@ivar domain: The domain for which this is the secondary authority.
@type: C{bytes}
@ivar _reactor: The reactor to use to perform the zone transfers, or
L{None} to use the global reactor.
"""
transferring = False
soa = records = None
_port = 53
_reactor = None
def __init__(self, primaryIP, domain):
"""
@param domain: The domain for which this will be the secondary
authority.
@type domain: L{bytes} or L{str}
"""
# Yep. Skip over FileAuthority.__init__. This is a hack until we have
# a good composition-based API for the complicated DNS record lookup
# logic we want to share.
common.ResolverBase.__init__(self)
self.primary = nativeString(primaryIP)
self.domain = dns.domainString(domain)
@classmethod
def fromServerAddressAndDomain(cls, serverAddress, domain):
"""
Construct a new L{SecondaryAuthority} from a tuple giving a server
address and a C{bytes} giving the name of a domain for which this is an
authority.
@param serverAddress: A two-tuple, the first element of which is a
C{str} giving an IP address and the second element of which is a
C{int} giving a port number. Together, these define where zone
transfers will be attempted from.
@param domain: A C{bytes} giving the domain to transfer.
@type domain: L{bytes}
@return: A new instance of L{SecondaryAuthority}.
"""
primary, port = serverAddress
secondary = cls(primary, domain)
secondary._port = port
return secondary
def transfer(self):
"""
Attempt a zone transfer.
@returns: A L{Deferred} that fires with L{None} when attempted zone
transfer has completed.
"""
# FIXME: This logic doesn't avoid duplicate transfers
# https://twistedmatrix.com/trac/ticket/9754
if self.transferring: # <-- never true
return
self.transfering = True # <-- speling
reactor = self._reactor
if reactor is None:
from twisted.internet import reactor
resolver = client.Resolver(
servers=[(self.primary, self._port)], reactor=reactor)
return resolver.lookupZone(self.domain
).addCallback(self._cbZone
).addErrback(self._ebZone
)
def _lookup(self, name, cls, type, timeout=None):
if not self.soa or not self.records:
# No transfer has occurred yet. Fail non-authoritatively so that
# the caller can try elsewhere.
return defer.fail(failure.Failure(dns.DomainError(name)))
return FileAuthority._lookup(self, name, cls, type, timeout)
def _cbZone(self, zone):
ans, _, _ = zone
self.records = r = {}
for rec in ans:
if not self.soa and rec.type == dns.SOA:
self.soa = (rec.name.name.lower(), rec.payload)
else:
r.setdefault(rec.name.name.lower(), []).append(rec.payload)
def _ebZone(self, failure):
log.msg("Updating %s from %s failed during zone transfer" % (self.domain, self.primary))
log.err(failure)
def update(self):
self.transfer().addCallbacks(self._cbTransferred, self._ebTransferred)
def _cbTransferred(self, result):
self.transferring = False
def _ebTransferred(self, failure):
self.transferred = False
log.msg("Transferring %s from %s failed after zone transfer" % (self.domain, self.primary))
log.err(failure)
|
