Log HTTP header for status codes != 200
[oddments/ddns.git] / src / ddns / system.py
CommitLineData
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
183 # 500 - Internal Server Error
184 elif e.code == 500:
185 raise DDNSInternalServerError(e.reason)
186
7a909224 187 # 503 - Service Unavailable
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188 elif e.code == 503:
189 raise DDNSServiceUnavailableError(e.reason)
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190
191 # Raise all other unhandled exceptions.
192 raise
193
f22ab085 194 except urllib2.URLError, e:
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195 if e.reason:
196 # Network Unreachable (e.g. no IPv6 access)
197 if e.reason.errno == 101:
198 raise DDNSNetworkUnreachableError
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199
200 # Connection Refused
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201 elif e.reason.errno == 111:
202 raise DDNSConnectionRefusedError
203
204 # Raise all other unhandled exceptions.
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205 raise
206
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207 except socket.timeout, e:
208 logger.debug(_("Connection timeout"))
209
210 raise DDNSConnectionTimeoutError
211
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212 def _format_query_args(self, data):
213 args = []
214
215 for k, v in data.items():
216 arg = "%s=%s" % (k, urllib.quote(v))
217 args.append(arg)
218
219 return "&".join(args)
220
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221 def _make_basic_auth_header(self, username, password):
222 authstring = "%s:%s" % (username, password)
223
224 # Encode authorization data in base64.
225 authstring = base64.encodestring(authstring)
226
227 # Remove any newline characters.
228 authstring = authstring.replace("\n", "")
229
230 return authstring
231
f22ab085 232 def get_address(self, proto):
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233 """
234 Returns the current IP address for
235 the given IP protocol.
236 """
237 try:
238 return self.__addresses[proto]
239
240 # IP is currently unknown and needs to be retrieved.
241 except KeyError:
242 self.__addresses[proto] = address = \
243 self._get_address(proto)
244
245 return address
246
247 def _get_address(self, proto):
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248 assert proto in ("ipv6", "ipv4")
249
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250 # IPFire 2 does not support IPv6.
251 if self.distro == "ipfire-2" and proto == "ipv6":
252 return
253
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254 # Check if the external IP address should be guessed from
255 # a remote server.
256 guess_ip = self.core.settings.get("guess_external_ip", "true")
3a061b71 257 guess_ip = guess_ip in ("true", "yes", "1")
30270391 258
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259 # If the external IP address should be used, we just do that.
260 if guess_ip:
022003bc 261 return self.guess_external_ip_address(proto)
f22ab085 262
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263 # Get the local IP address.
264 local_ip_address = self.get_local_ip_address(proto)
265
266 # If the local IP address is not usable, we must guess
267 # the correct IP address...
268 if not self._is_usable_ip_address(proto, local_ip_address):
269 local_ip_address = self.guess_external_ip_address(proto)
270
271 return local_ip_address
272
273 def _is_usable_ip_address(self, proto, address):
274 """
275 Returns True is the local IP address is usable
276 for dynamic DNS (i.e. is not a RFC1918 address or similar).
277 """
278 if proto == "ipv4":
279 # This is not the most perfect solution to match
280 # these addresses, but instead of pulling in an entire
281 # library to handle the IP addresses better, we match
282 # with regular expressions instead.
283 matches = (
284 # RFC1918 address space
285 r"^10\.\d+\.\d+\.\d+$",
286 r"^192\.168\.\d+\.\d+$",
287 r"^172\.(1[6-9]|2[0-9]|31)\.\d+\.\d+$",
288
289 # Dual Stack Lite address space
580f98e8 290 r"^100\.(6[4-9]|[7-9][0-9]|1[01][0-9]|12[0-7])\.\d+\.\d+$",
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291 )
292
293 for match in matches:
294 m = re.match(match, address)
295 if m is None:
296 continue
297
298 # Found a match. IP address is not usable.
299 return False
300
301 # In all other cases, return OK.
302 return True
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303
304 def resolve(self, hostname, proto=None):
305 addresses = []
306
307 if proto is None:
308 family = 0
309 elif proto == "ipv6":
310 family = socket.AF_INET6
311 elif proto == "ipv4":
312 family = socket.AF_INET
313 else:
314 raise ValueError("Protocol not supported: %s" % proto)
315
316 # Resolve the host address.
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317 try:
318 response = socket.getaddrinfo(hostname, None, family)
319 except socket.gaierror, e:
320 # Name or service not known
321 if e.errno == -2:
322 return []
323
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324 # No record for requested family available (e.g. no AAAA)
325 elif e.errno == -5:
326 return []
327
73f2bc0b 328 raise
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329
330 # Handle responses.
331 for family, socktype, proto, canonname, sockaddr in response:
332 # IPv6
333 if family == socket.AF_INET6:
334 address, port, flow_info, scope_id = sockaddr
335
336 # Only use the global scope.
337 if not scope_id == 0:
338 continue
339
340 # IPv4
341 elif family == socket.AF_INET:
342 address, port = sockaddr
343
344 # Ignore everything else...
345 else:
346 continue
347
348 # Add to repsonse list if not already in there.
349 if not address in addresses:
350 addresses.append(address)
351
352 return addresses
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353
354 def _get_distro_identifier(self):
355 """
356 Returns a unique identifier for the distribution
357 we are running on.
358 """
359 os_release = self.__parse_os_release()
360 if os_release:
361 return os_release
362
363 system_release = self.__parse_system_release()
364 if system_release:
365 return system_release
366
367 # If nothing else could be found, we return
368 # just "unknown".
369 return "unknown"
370
371 def __parse_os_release(self):
372 """
373 Tries to parse /etc/os-release and
374 returns a unique distribution identifier
375 if the file exists.
376 """
377 try:
378 f = open("/etc/os-release", "r")
379 except IOError, e:
380 # File not found
381 if e.errno == 2:
382 return
383
384 raise
385
386 os_release = {}
387 with f:
388 for line in f.readlines():
389 m = re.match(r"^([A-Z\_]+)=(.*)$", line)
390 if m is None:
391 continue
392
393 os_release[m.group(1)] = m.group(2)
394
395 try:
396 return "%(ID)s-%(VERSION_ID)s" % os_release
397 except KeyError:
398 return
399
400 def __parse_system_release(self):
401 """
402 Tries to parse /etc/system-release and
403 returns a unique distribution identifier
404 if the file exists.
405 """
406 try:
407 f = open("/etc/system-release", "r")
408 except IOError, e:
409 # File not found
410 if e.errno == 2:
411 return
412
413 raise
414
415 with f:
416 # Read first line
417 line = f.readline()
418
419 # Check for IPFire systems
420 m = re.match(r"^IPFire (\d).(\d+)", line)
421 if m:
422 return "ipfire-%s" % m.group(1)