tunnel.py

   1 import os, random, traceback, time
   2 import plib, utils, db
   3
   4 log = None
   5
   6 class TunnelManager:
   7
   8     def __init__(self, write_pipe, peer_db, openvpn_args, refresh, connection_count, refresh_rate):
   9         self._write_pipe = write_pipe
  10         self._peer_db = peer_db
  11         self._connection_dict = {}
  12         self._ovpn_args = openvpn_args
  13         self._refresh_time = refresh
  14         self.free_interface_set = set(('client1', 'client2', 'client3', 'client4', 'client5',
  15                                        'client6', 'client7', 'client8', 'client9', 'client10'))
  16         self.next_refresh = time.time()
  17
  18         # TODO : choose this automatically
  19         self._client_count = connection_count/2
  20         self._refresh_count = refresh_rate*self._client_count
  21
  22     def refresh(self):
  23         utils.log('Refreshing the tunnels', 2)
  24         self._cleanDeads()
  25         self._removeSomeTunnels()
  26         self._makeNewTunnels()
  27         self.next_refresh = time.time() + self._refresh_time
  28
  29     def _cleanDeads(self):
  30         for id in self._connection_dict.keys():
  31             p, iface = self._connection_dict[id]
  32             if p.poll() != None:
  33                 utils.log('Connection with %s has failed with return code %s' % (id, p.returncode), 3)
  34                 self.free_interface_set.add(iface)
  35                 self._peer_db.unusePeer(id)
  36                 del self._connection_dict[id]
  37
  38     def _removeSomeTunnels(self):
  39         for i in range(0, max(0, len(self._connection_dict) - self._client_count + self._refresh_count)):
  40             peer_id = random.choice(self._connection_dict.keys())
  41             self._kill(peer_id)
  42
  43     def _kill(self, peer_id):
  44         utils.log('Killing the connection with id ' + str(peer_id), 2)
  45         p, iface = self._connection_dict.pop(peer_id)
  46         p.kill()
  47         self.free_interface_set.add(iface)
  48         self._peer_db.unusePeer(peer_id)
  49
  50     def _makeNewTunnels(self):
  51         utils.log('Making %i new tunnels' % (self._client_count - len(self._connection_dict)), 3)
  52         try:
  53             for peer_id, ip, port, proto in self._peer_db.getUnusedPeers(self._client_count - len(self._connection_dict)):
  54                 utils.log('Establishing a connection with id %s (%s:%s)' % (peer_id, ip, port), 2)
  55                 iface = self.free_interface_set.pop()
  56                 self._connection_dict[peer_id] = ( plib.client( ip, self._write_pipe,
  57                     '--dev', iface, '--proto', proto, '--rport', str(port), *self._ovpn_args,
  58                     stdout=os.open(os.path.join(log, 'vifibnet.client.%s.log' % (peer_id,)),
  59                                    os.O_WRONLY|os.O_CREAT|os.O_TRUNC) ), iface)
  60                 self._peer_db.usePeer(peer_id)
  61         except KeyError:
  62             utils.log("Can't establish connection with %s : no available interface" % ip, 2)
  63         except Exception:
  64             traceback.print_exc()