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configure: Fix systemd detection
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f22ab085 1#!/usr/bin/python
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2###############################################################################
3# #
4# ddns - A dynamic DNS client for IPFire #
5# Copyright (C) 2012 IPFire development team #
6# #
7# This program is free software: you can redistribute it and/or modify #
8# it under the terms of the GNU General Public License as published by #
9# the Free Software Foundation, either version 3 of the License, or #
10# (at your option) any later version. #
11# #
12# This program is distributed in the hope that it will be useful, #
13# but WITHOUT ANY WARRANTY; without even the implied warranty of #
14# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #
15# GNU General Public License for more details. #
16# #
17# You should have received a copy of the GNU General Public License #
18# along with this program. If not, see <http://www.gnu.org/licenses/>. #
19# #
20###############################################################################
f22ab085 21
d4c5c0d5 22import base64
f22ab085 23import re
6cecd141 24import socket
adb124d0 25import urllib
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26import urllib2
27
28from __version__ import CLIENT_VERSION
7a909224 29from .errors import *
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30from i18n import _
31
32# Initialize the logger.
33import logging
34logger = logging.getLogger("ddns.system")
35logger.propagate = 1
36
37class DDNSSystem(object):
38 """
39 The DDNSSystem class adds a layer of abstraction
40 between the ddns software and the system.
41 """
42
43 # The default useragent.
44 USER_AGENT = "IPFireDDNSUpdater/%s" % CLIENT_VERSION
45
46 def __init__(self, core):
47 # Connection to the core of the program.
48 self.core = core
49
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50 # Address cache.
51 self.__addresses = {}
52
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53 # Find out on which distribution we are running.
54 self.distro = self._get_distro_identifier()
55 logger.debug(_("Running on distribution: %s") % self.distro)
56
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57 @property
58 def proxy(self):
59 proxy = self.core.settings.get("proxy")
60
61 # Strip http:// at the beginning.
fd898828 62 if proxy and proxy.startswith("http://"):
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63 proxy = proxy[7:]
64
65 return proxy
66
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67 def get_local_ip_address(self, proto):
68 # Legacy code for IPFire 2.
69 if self.distro == "ipfire-2" and proto == "ipv4":
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70 try:
71 with open("/var/ipfire/red/local-ipaddress") as f:
72 return f.readline()
73
74 except IOError, e:
75 # File not found
76 if e.errno == 2:
77 return
78
79 raise
80
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81 # XXX TODO
82 raise NotImplementedError
7f75b957 83
46c23a71 84 def _guess_external_ip_address(self, url, timeout=10):
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85 """
86 Sends a request to an external web server
87 to determine the current default IP address.
88 """
7a909224 89 try:
46c23a71 90 response = self.send_request(url, timeout=timeout)
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91
92 # If the server could not be reached, we will return nothing.
93 except DDNSNetworkError:
94 return
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95
96 if not response.code == 200:
97 return
98
99 match = re.search(r"^Your IP address is: (.*)$", response.read())
100 if match is None:
101 return
102
103 return match.group(1)
104
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105 def guess_external_ip_address(self, family, **kwargs):
106 if family == "ipv6":
107 url = "http://checkip6.dns.lightningwirelabs.com"
108 elif family == "ipv4":
109 url = "http://checkip4.dns.lightningwirelabs.com"
110 else:
111 raise ValueError("unknown address family")
f22ab085 112
022003bc 113 return self._guess_external_ip_address(url, **kwargs)
f22ab085 114
d4c5c0d5 115 def send_request(self, url, method="GET", data=None, username=None, password=None, timeout=30):
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116 assert method in ("GET", "POST")
117
118 # Add all arguments in the data dict to the URL and escape them properly.
119 if method == "GET" and data:
120 query_args = self._format_query_args(data)
121 data = None
122
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123 if "?" in url:
124 url = "%s&%s" % (url, query_args)
125 else:
126 url = "%s?%s" % (url, query_args)
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127
128 logger.debug("Sending request (%s): %s" % (method, url))
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129 if data:
130 logger.debug(" data: %s" % data)
131
132 req = urllib2.Request(url, data=data)
133
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134 if username and password:
135 basic_auth_header = self._make_basic_auth_header(username, password)
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136 req.add_header("Authorization", "Basic %s" % basic_auth_header)
137
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138 # Set the user agent.
139 req.add_header("User-Agent", self.USER_AGENT)
140
141 # All requests should not be cached anywhere.
142 req.add_header("Pragma", "no-cache")
143
144 # Set the upstream proxy if needed.
145 if self.proxy:
146 logger.debug("Using proxy: %s" % self.proxy)
147
148 # Configure the proxy for this request.
149 req.set_proxy(self.proxy, "http")
150
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151 assert req.get_method() == method
152
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153 logger.debug(_("Request header:"))
154 for k, v in req.headers.items():
155 logger.debug(" %s: %s" % (k, v))
156
157 try:
7a909224 158 resp = urllib2.urlopen(req, timeout=timeout)
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159
160 # Log response header.
09c496c5 161 logger.debug(_("Response header (Status Code %s):") % resp.code)
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162 for k, v in resp.info().items():
163 logger.debug(" %s: %s" % (k, v))
164
165 # Return the entire response object.
166 return resp
167
7a909224 168 except urllib2.HTTPError, e:
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169 # Log response header.
170 logger.debug(_("Response header (Status Code %s):") % e.code)
171 for k, v in e.hdrs.items():
172 logger.debug(" %s: %s" % (k, v))
173
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174 # 400 - Bad request
175 if e.code == 400:
176 raise DDNSRequestError(e.reason)
177
178 # 401 - Authorization Required
179 # 403 - Forbidden
180 elif e.code in (401, 403):
181 raise DDNSAuthenticationError(e.reason)
182
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183 # 404 - Not found
184 # Either the provider has changed the API, or
185 # there is an error on the server
186 elif e.code == 404:
187 raise DDNSNotFound(e.reason)
188
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189 # 500 - Internal Server Error
190 elif e.code == 500:
191 raise DDNSInternalServerError(e.reason)
192
7a909224 193 # 503 - Service Unavailable
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194 elif e.code == 503:
195 raise DDNSServiceUnavailableError(e.reason)
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196
197 # Raise all other unhandled exceptions.
198 raise
199
f22ab085 200 except urllib2.URLError, e:
7a909224 201 if e.reason:
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202 # Name or service not known
203 if e.reason.errno == -2:
204 raise DDNSResolveError
205
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206 # Network Unreachable (e.g. no IPv6 access)
207 if e.reason.errno == 101:
208 raise DDNSNetworkUnreachableError
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209
210 # Connection Refused
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211 elif e.reason.errno == 111:
212 raise DDNSConnectionRefusedError
213
214 # Raise all other unhandled exceptions.
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215 raise
216
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217 except socket.timeout, e:
218 logger.debug(_("Connection timeout"))
219
220 raise DDNSConnectionTimeoutError
221
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222 def _format_query_args(self, data):
223 args = []
224
225 for k, v in data.items():
226 arg = "%s=%s" % (k, urllib.quote(v))
227 args.append(arg)
228
229 return "&".join(args)
230
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231 def _make_basic_auth_header(self, username, password):
232 authstring = "%s:%s" % (username, password)
233
234 # Encode authorization data in base64.
235 authstring = base64.encodestring(authstring)
236
237 # Remove any newline characters.
238 authstring = authstring.replace("\n", "")
239
240 return authstring
241
f22ab085 242 def get_address(self, proto):
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243 """
244 Returns the current IP address for
245 the given IP protocol.
246 """
247 try:
248 return self.__addresses[proto]
249
250 # IP is currently unknown and needs to be retrieved.
251 except KeyError:
252 self.__addresses[proto] = address = \
253 self._get_address(proto)
254
255 return address
256
257 def _get_address(self, proto):
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258 assert proto in ("ipv6", "ipv4")
259
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260 # IPFire 2 does not support IPv6.
261 if self.distro == "ipfire-2" and proto == "ipv6":
262 return
263
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264 # Check if the external IP address should be guessed from
265 # a remote server.
266 guess_ip = self.core.settings.get("guess_external_ip", "true")
3a061b71 267 guess_ip = guess_ip in ("true", "yes", "1")
30270391 268
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269 # If the external IP address should be used, we just do that.
270 if guess_ip:
022003bc 271 return self.guess_external_ip_address(proto)
f22ab085 272
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273 # Get the local IP address.
274 local_ip_address = self.get_local_ip_address(proto)
275
276 # If the local IP address is not usable, we must guess
277 # the correct IP address...
278 if not self._is_usable_ip_address(proto, local_ip_address):
279 local_ip_address = self.guess_external_ip_address(proto)
280
281 return local_ip_address
282
283 def _is_usable_ip_address(self, proto, address):
284 """
285 Returns True is the local IP address is usable
286 for dynamic DNS (i.e. is not a RFC1918 address or similar).
287 """
288 if proto == "ipv4":
289 # This is not the most perfect solution to match
290 # these addresses, but instead of pulling in an entire
291 # library to handle the IP addresses better, we match
292 # with regular expressions instead.
293 matches = (
294 # RFC1918 address space
295 r"^10\.\d+\.\d+\.\d+$",
296 r"^192\.168\.\d+\.\d+$",
297 r"^172\.(1[6-9]|2[0-9]|31)\.\d+\.\d+$",
298
299 # Dual Stack Lite address space
580f98e8 300 r"^100\.(6[4-9]|[7-9][0-9]|1[01][0-9]|12[0-7])\.\d+\.\d+$",
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301 )
302
303 for match in matches:
304 m = re.match(match, address)
305 if m is None:
306 continue
307
308 # Found a match. IP address is not usable.
309 return False
310
311 # In all other cases, return OK.
312 return True
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313
314 def resolve(self, hostname, proto=None):
315 addresses = []
316
317 if proto is None:
318 family = 0
319 elif proto == "ipv6":
320 family = socket.AF_INET6
321 elif proto == "ipv4":
322 family = socket.AF_INET
323 else:
324 raise ValueError("Protocol not supported: %s" % proto)
325
326 # Resolve the host address.
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327 try:
328 response = socket.getaddrinfo(hostname, None, family)
329 except socket.gaierror, e:
330 # Name or service not known
331 if e.errno == -2:
332 return []
333
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334 # Temporary failure in name resolution
335 elif e.errno == -3:
336 raise DDNSResolveError(hostname)
337
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338 # No record for requested family available (e.g. no AAAA)
339 elif e.errno == -5:
340 return []
341
73f2bc0b 342 raise
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343
344 # Handle responses.
345 for family, socktype, proto, canonname, sockaddr in response:
346 # IPv6
347 if family == socket.AF_INET6:
348 address, port, flow_info, scope_id = sockaddr
349
350 # Only use the global scope.
351 if not scope_id == 0:
352 continue
353
354 # IPv4
355 elif family == socket.AF_INET:
356 address, port = sockaddr
357
358 # Ignore everything else...
359 else:
360 continue
361
362 # Add to repsonse list if not already in there.
363 if not address in addresses:
364 addresses.append(address)
365
366 return addresses
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367
368 def _get_distro_identifier(self):
369 """
370 Returns a unique identifier for the distribution
371 we are running on.
372 """
373 os_release = self.__parse_os_release()
374 if os_release:
375 return os_release
376
377 system_release = self.__parse_system_release()
378 if system_release:
379 return system_release
380
381 # If nothing else could be found, we return
382 # just "unknown".
383 return "unknown"
384
385 def __parse_os_release(self):
386 """
387 Tries to parse /etc/os-release and
388 returns a unique distribution identifier
389 if the file exists.
390 """
391 try:
392 f = open("/etc/os-release", "r")
393 except IOError, e:
394 # File not found
395 if e.errno == 2:
396 return
397
398 raise
399
400 os_release = {}
401 with f:
402 for line in f.readlines():
403 m = re.match(r"^([A-Z\_]+)=(.*)$", line)
404 if m is None:
405 continue
406
407 os_release[m.group(1)] = m.group(2)
408
409 try:
410 return "%(ID)s-%(VERSION_ID)s" % os_release
411 except KeyError:
412 return
413
414 def __parse_system_release(self):
415 """
416 Tries to parse /etc/system-release and
417 returns a unique distribution identifier
418 if the file exists.
419 """
420 try:
421 f = open("/etc/system-release", "r")
422 except IOError, e:
423 # File not found
424 if e.errno == 2:
425 return
426
427 raise
428
429 with f:
430 # Read first line
431 line = f.readline()
432
433 # Check for IPFire systems
434 m = re.match(r"^IPFire (\d).(\d+)", line)
435 if m:
436 return "ipfire-%s" % m.group(1)