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[oddments/ddns.git] / ddns / system.py
1 #!/usr/bin/python
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 ###############################################################################
21
22 import re
23 import urllib2
24
25 from __version__ import CLIENT_VERSION
26 from i18n import _
27
28 # Initialize the logger.
29 import logging
30 logger = logging.getLogger("ddns.system")
31 logger.propagate = 1
32
33 class DDNSSystem(object):
34         """
35                 The DDNSSystem class adds a layer of abstraction
36                 between the ddns software and the system.
37         """
38
39         # The default useragent.
40         USER_AGENT = "IPFireDDNSUpdater/%s" % CLIENT_VERSION
41
42         def __init__(self, core):
43                 # Connection to the core of the program.
44                 self.core = core
45
46         @property
47         def proxy(self):
48                 proxy = self.core.settings.get("proxy")
49
50                 # Strip http:// at the beginning.
51                 if proxy.startswith("http://"):
52                         proxy = proxy[7:]
53
54                 return proxy
55
56         def guess_external_ipv4_address(self):
57                 """
58                         Sends a request to the internet to determine
59                         the public IP address.
60
61                         XXX does not work for IPv6.
62                 """
63                 response = self.send_request("http://checkip.dyndns.org/")
64
65                 if response.code == 200:
66                         match = re.search(r"Current IP Address: (\d+.\d+.\d+.\d+)", response.read())
67                         if match is None:
68                                 return
69
70                         return match.group(1)
71
72         def send_request(self, url, data=None, timeout=30):
73                 logger.debug("Sending request: %s" % url)
74                 if data:
75                         logger.debug("  data: %s" % data)
76
77                 req = urllib2.Request(url, data=data)
78
79                 # Set the user agent.
80                 req.add_header("User-Agent", self.USER_AGENT)
81
82                 # All requests should not be cached anywhere.
83                 req.add_header("Pragma", "no-cache")
84
85                 # Set the upstream proxy if needed.
86                 if self.proxy:
87                         logger.debug("Using proxy: %s" % self.proxy)
88
89                         # Configure the proxy for this request.
90                         req.set_proxy(self.proxy, "http")
91
92                 logger.debug(_("Request header:"))
93                 for k, v in req.headers.items():
94                         logger.debug("  %s: %s" % (k, v))
95
96                 try:
97                         resp = urllib2.urlopen(req)
98
99                         # Log response header.
100                         logger.debug(_("Response header:"))
101                         for k, v in resp.info().items():
102                                 logger.debug("  %s: %s" % (k, v))
103
104                         # Return the entire response object.
105                         return resp
106
107                 except urllib2.URLError, e:
108                         raise
109
110         def get_address(self, proto):
111                 assert proto in ("ipv6", "ipv4")
112
113                 if proto == "ipv4":
114                         # Check if the external IP address should be guessed from
115                         # a remote server.
116                         guess_ip = self.core.settings.get("guess_external_ip", "")
117
118                         # If the external IP address should be used, we just do
119                         # that.
120                         if guess_ip in ("true", "yes", "1"):
121                                 return self.guess_external_ipv4_address()
122
123                 # XXX TODO
124                 assert False