src/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 base64
  23 import re
  24 import urllib
  25 import urllib2
  26
  27 from __version__ import CLIENT_VERSION
  28 from i18n import _
  29
  30 # Initialize the logger.
  31 import logging
  32 logger = logging.getLogger("ddns.system")
  33 logger.propagate = 1
  34
  35 class DDNSSystem(object):
  36         """
  37                 The DDNSSystem class adds a layer of abstraction
  38                 between the ddns software and the system.
  39         """
  40
  41         # The default useragent.
  42         USER_AGENT = "IPFireDDNSUpdater/%s" % CLIENT_VERSION
  43
  44         def __init__(self, core):
  45                 # Connection to the core of the program.
  46                 self.core = core
  47
  48         @property
  49         def proxy(self):
  50                 proxy = self.core.settings.get("proxy")
  51
  52                 # Strip http:// at the beginning.
  53                 if proxy and proxy.startswith("http://"):
  54                         proxy = proxy[7:]
  55
  56                 return proxy
  57
  58         def guess_external_ipv6_address(self):
  59                 """
  60                         Sends a request to an external web server
  61                         to determine the current default IP address.
  62                 """
  63                 response = self.send_request("http://checkip6.dns.lightningwirelabs.com")
  64
  65                 if not response.code == 200:
  66                         return
  67
  68                 match = re.search(r"^Your IP address is: (.*)$", response.read())
  69                 if match is None:
  70                         return
  71
  72                 return match.group(1)
  73
  74         def guess_external_ipv4_address(self):
  75                 """
  76                         Sends a request to the internet to determine
  77                         the public IP address.
  78
  79                         XXX does not work for IPv6.
  80                 """
  81                 response = self.send_request("http://checkip4.dns.lightningwirelabs.com")
  82
  83                 if response.code == 200:
  84                         match = re.search(r"Your IP address is: (\d+.\d+.\d+.\d+)", response.read())
  85                         if match is None:
  86                                 return
  87
  88                         return match.group(1)
  89
  90         def send_request(self, url, method="GET", data=None, username=None, password=None, timeout=30):
  91                 assert method in ("GET", "POST")
  92
  93                 # Add all arguments in the data dict to the URL and escape them properly.
  94                 if method == "GET" and data:
  95                         query_args = self._format_query_args(data)
  96                         data = None
  97
  98                         url = "%s?%s" % (url, query_args)
  99
 100                 logger.debug("Sending request (%s): %s" % (method, url))
 101                 if data:
 102                         logger.debug("  data: %s" % data)
 103
 104                 req = urllib2.Request(url, data=data)
 105
 106                 if username and password:
 107                         basic_auth_header = self._make_basic_auth_header(username, password)
 108                         print repr(basic_auth_header)
 109                         req.add_header("Authorization", "Basic %s" % basic_auth_header)
 110
 111                 # Set the user agent.
 112                 req.add_header("User-Agent", self.USER_AGENT)
 113
 114                 # All requests should not be cached anywhere.
 115                 req.add_header("Pragma", "no-cache")
 116
 117                 # Set the upstream proxy if needed.
 118                 if self.proxy:
 119                         logger.debug("Using proxy: %s" % self.proxy)
 120
 121                         # Configure the proxy for this request.
 122                         req.set_proxy(self.proxy, "http")
 123
 124                 assert req.get_method() == method
 125
 126                 logger.debug(_("Request header:"))
 127                 for k, v in req.headers.items():
 128                         logger.debug("  %s: %s" % (k, v))
 129
 130                 try:
 131                         resp = urllib2.urlopen(req)
 132
 133                         # Log response header.
 134                         logger.debug(_("Response header:"))
 135                         for k, v in resp.info().items():
 136                                 logger.debug("  %s: %s" % (k, v))
 137
 138                         # Return the entire response object.
 139                         return resp
 140
 141                 except urllib2.URLError, e:
 142                         raise
 143
 144         def _format_query_args(self, data):
 145                 args = []
 146
 147                 for k, v in data.items():
 148                         arg = "%s=%s" % (k, urllib.quote(v))
 149                         args.append(arg)
 150
 151                 return "&".join(args)
 152
 153         def _make_basic_auth_header(self, username, password):
 154                 authstring = "%s:%s" % (username, password)
 155
 156                 # Encode authorization data in base64.
 157                 authstring = base64.encodestring(authstring)
 158
 159                 # Remove any newline characters.
 160                 authstring = authstring.replace("\n", "")
 161
 162                 return authstring
 163
 164         def get_address(self, proto):
 165                 assert proto in ("ipv6", "ipv4")
 166
 167                 # Check if the external IP address should be guessed from
 168                 # a remote server.
 169                 guess_ip = self.core.settings.get("guess_external_ip", "true")
 170
 171                 # If the external IP address should be used, we just do
 172                 # that.
 173                 if guess_ip in ("true", "yes", "1"):
 174                         if proto == "ipv6":
 175                                 return self.guess_external_ipv6_address()
 176
 177                         elif proto == "ipv4":
 178                                 return self.guess_external_ipv4_address()
 179
 180                 # XXX TODO
 181                 assert False