summaryrefslogtreecommitdiff
path: root/src/leap/bitmask/services/eip/vpnprocess.py
blob: a96f176ec78f4a623737f663b667a7d5cc71f21c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
# -*- coding: utf-8 -*-
# vpnprocess.py
# Copyright (C) 2013 LEAP
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
"""
VPN Manager, spawned in a custom processProtocol.
"""
import logging
import os
import psutil
import psutil.error
import shutil
import socket

from PySide import QtCore

from leap.bitmask.config.providerconfig import ProviderConfig
from leap.bitmask.services.eip.vpnlaunchers import get_platform_launcher
from leap.bitmask.services.eip.eipconfig import EIPConfig
from leap.bitmask.services.eip.udstelnet import UDSTelnet
from leap.bitmask.util import first
from leap.bitmask.platform_init import IS_MAC
from leap.common.check import leap_assert, leap_assert_type

logger = logging.getLogger(__name__)
vpnlog = logging.getLogger('leap.openvpn')

from twisted.internet import protocol
from twisted.internet import defer
from twisted.internet import error as internet_error
from twisted.internet.task import LoopingCall


class VPNSignals(QtCore.QObject):
    """
    These are the signals that we use to let the UI know
    about the events we are polling.
    They are instantiated in the VPN object and passed along
    till the VPNProcess.
    """
    state_changed = QtCore.Signal(dict)
    status_changed = QtCore.Signal(dict)
    process_finished = QtCore.Signal(int)

    def __init__(self):
        QtCore.QObject.__init__(self)


class OpenVPNAlreadyRunning(Exception):
    message = ("Another openvpn instance is already running, and could "
               "not be stopped.")


class AlienOpenVPNAlreadyRunning(Exception):
    message = ("Another openvpn instance is already running, and could "
               "not be stopped because it was not launched by LEAP.")


class VPN(object):
    """
    This is the high-level object that the GUI is dealing with.
    It exposes the start and terminate methods.

    On start, it spawns a VPNProcess instance that will use a vpnlauncher
    suited for the running platform and connect to the management interface
    opened by the openvpn process, executing commands over that interface on
    demand.
    """
    TERMINATE_MAXTRIES = 10
    TERMINATE_WAIT = 1  # secs

    OPENVPN_VERB = "openvpn_verb"

    def __init__(self, **kwargs):
        """
        Instantiate empty attributes and get a copy
        of a QObject containing the QSignals that we will pass along
        to the VPNManager.
        """
        from twisted.internet import reactor
        self._vpnproc = None
        self._pollers = []
        self._reactor = reactor
        self._qtsigs = VPNSignals()

        self._openvpn_verb = kwargs.get(self.OPENVPN_VERB, None)

    @property
    def qtsigs(self):
        return self._qtsigs

    def start(self, *args, **kwargs):
        """
        Starts the openvpn subprocess.

        :param args: args to be passed to the VPNProcess
        :type args: tuple

        :param kwargs: kwargs to be passed to the VPNProcess
        :type kwargs: dict
        """
        self._stop_pollers()
        kwargs['qtsigs'] = self.qtsigs
        kwargs['openvpn_verb'] = self._openvpn_verb

        # start the main vpn subprocess
        vpnproc = VPNProcess(*args, **kwargs)
                             #qtsigs=self.qtsigs,
                             #openvpn_verb=self._openvpn_verb)

        if vpnproc.get_openvpn_process():
            logger.info("Another vpn process is running. Will try to stop it.")
            vpnproc.stop_if_already_running()

        cmd = vpnproc.getCommand()
        env = os.environ
        for key, val in vpnproc.vpn_env.items():
            env[key] = val

        self._reactor.spawnProcess(vpnproc, cmd[0], cmd, env)
        self._vpnproc = vpnproc

        # add pollers for status and state
        # this could be extended to a collection of
        # generic watchers

        poll_list = [LoopingCall(vpnproc.pollStatus),
                     LoopingCall(vpnproc.pollState)]
        self._pollers.extend(poll_list)
        self._start_pollers()

    def _kill_if_left_alive(self, tries=0):
        """
        Check if the process is still alive, and sends a
        SIGKILL after a timeout period.

        :param tries: counter of tries, used in recursion
        :type tries: int
        """
        from twisted.internet import reactor
        while tries < self.TERMINATE_MAXTRIES:
            if self._vpnproc.transport.pid is None:
                logger.debug("Process has been happily terminated.")
                return
            else:
                logger.debug("Process did not die, waiting...")
            tries += 1
            reactor.callLater(self.TERMINATE_WAIT,
                              self._kill_if_left_alive, tries)

        # after running out of patience, we try a killProcess
        logger.debug("Process did not died. Sending a SIGKILL.")
        self.killit()

    def killit(self):
        """
        Sends a kill signal to the process.
        """
        self._stop_pollers()
        self._vpnproc.aborted = True
        self._vpnproc.killProcess()

    def terminate(self, shutdown=False):
        """
        Stops the openvpn subprocess.

        Attempts to send a SIGTERM first, and after a timeout
        it sends a SIGKILL.
        """
        from twisted.internet import reactor
        self._stop_pollers()

        # First we try to be polite and send a SIGTERM...
        if self._vpnproc:
            self._sentterm = True
            self._vpnproc.terminate_openvpn(shutdown=shutdown)

            # ...but we also trigger a countdown to be unpolite
            # if strictly needed.

            # XXX Watch out! This will fail NOW since we are running
            # openvpn as root as a workaround for some connection issues.
            reactor.callLater(
                self.TERMINATE_WAIT, self._kill_if_left_alive)

    def _start_pollers(self):
        """
        Iterate through the registered observers
        and start the looping call for them.
        """
        for poller in self._pollers:
            poller.start(VPNManager.POLL_TIME)

    def _stop_pollers(self):
        """
        Iterate through the registered observers
        and stop the looping calls if they are running.
        """
        for poller in self._pollers:
            if poller.running:
                poller.stop()
        self._pollers = []


class VPNManager(object):
    """
    This is a mixin that we use in the VPNProcess class.
    Here we get together all methods related with the openvpn management
    interface.

    A copy of a QObject containing signals as attributes is passed along
    upon initialization, and we use that object to emit signals to qt-land.

    For more info about management methods::

      zcat `dpkg -L openvpn | grep management`
    """

    # Timers, in secs
    POLL_TIME = 2.5 if IS_MAC else 1.0
    CONNECTION_RETRY_TIME = 1

    TS_KEY = "ts"
    STATUS_STEP_KEY = "status_step"
    OK_KEY = "ok"
    IP_KEY = "ip"
    REMOTE_KEY = "remote"

    TUNTAP_READ_KEY = "tun_tap_read"
    TUNTAP_WRITE_KEY = "tun_tap_write"
    TCPUDP_READ_KEY = "tcp_udp_read"
    TCPUDP_WRITE_KEY = "tcp_udp_write"
    AUTH_READ_KEY = "auth_read"

    def __init__(self, qtsigs=None):
        """
        Initializes the VPNManager.

        :param qtsigs: a QObject containing the Qt signals used by the UI
                       to give feedback about state changes.
        :type qtsigs: QObject
        """
        from twisted.internet import reactor
        self._reactor = reactor
        self._tn = None
        self._qtsigs = qtsigs
        self._aborted = False

    @property
    def qtsigs(self):
        return self._qtsigs

    @property
    def aborted(self):
        return self._aborted

    @aborted.setter
    def aborted(self, value):
        self._aborted = value

    def _seek_to_eof(self):
        """
        Read as much as available. Position seek pointer to end of stream
        """
        try:
            self._tn.read_eager()
        except EOFError:
            logger.debug("Could not read from socket. Assuming it died.")
            return

    def _send_command(self, command, until=b"END"):
        """
        Sends a command to the telnet connection and reads until END
        is reached.

        :param command: command to send
        :type command: str

        :param until: byte delimiter string for reading command output
        :type until: byte str

        :return: response read
        :rtype: list
        """
        leap_assert(self._tn, "We need a tn connection!")

        try:
            self._tn.write("%s\n" % (command,))
            buf = self._tn.read_until(until, 2)
            self._seek_to_eof()
            blist = buf.split('\r\n')
            if blist[-1].startswith(until):
                del blist[-1]
                return blist
            else:
                return []

        except socket.error:
            # XXX should get a counter and repeat only
            # after mod X times.
            logger.warning('socket error (command was: "%s")' % (command,))
            self._close_management_socket(announce=False)
            logger.debug('trying to connect to management again')
            self.try_to_connect_to_management(max_retries=5)
            return []

        # XXX should move this to a errBack!
        except Exception as e:
            logger.warning("Error sending command %s: %r" %
                           (command, e))
        return []

    def _close_management_socket(self, announce=True):
        """
        Close connection to openvpn management interface.
        """
        logger.debug('closing socket')
        if announce:
            self._tn.write("quit\n")
            self._tn.read_all()
        self._tn.get_socket().close()
        self._tn = None

    def _connect_management(self, socket_host, socket_port):
        """
        Connects to the management interface on the specified
        socket_host socket_port.

        :param socket_host: either socket path (unix) or socket IP
        :type socket_host: str

        :param socket_port: either string "unix" if it's a unix
                            socket, or port otherwise
        :type socket_port: str
        """
        if self.is_connected():
            self._close_management_socket()

        try:
            self._tn = UDSTelnet(socket_host, socket_port)

            # XXX make password optional
            # specially for win. we should generate
            # the pass on the fly when invoking manager
            # from conductor

            # self.tn.read_until('ENTER PASSWORD:', 2)
            # self.tn.write(self.password + '\n')
            # self.tn.read_until('SUCCESS:', 2)
            if self._tn:
                self._tn.read_eager()

        # XXX move this to the Errback
        except Exception as e:
            logger.warning("Could not connect to OpenVPN yet: %r" % (e,))
            self._tn = None

    def _connectCb(self, *args):
        """
        Callback for connection.

        :param args: not used
        """
        if self._tn:
            logger.info('Connected to management')
        else:
            logger.debug('Cannot connect to management...')

    def _connectErr(self, failure):
        """
        Errorback for connection.

        :param failure: Failure
        """
        logger.warning(failure)

    def connect_to_management(self, host, port):
        """
        Connect to a management interface.

        :param host: the host of the management interface
        :type host: str

        :param port: the port of the management interface
        :type port: str

        :returns: a deferred
        """
        self.connectd = defer.maybeDeferred(
            self._connect_management, host, port)
        self.connectd.addCallbacks(self._connectCb, self._connectErr)
        return self.connectd

    def is_connected(self):
        """
        Returns the status of the management interface.

        :returns: True if connected, False otherwise
        :rtype: bool
        """
        return True if self._tn else False

    def try_to_connect_to_management(self, retry=0, max_retries=None):
        """
        Attempts to connect to a management interface, and retries
        after CONNECTION_RETRY_TIME if not successful.

        :param retry: number of the retry
        :type retry: int
        """
        if max_retries and retry > max_retries:
            logger.warning("Max retries reached while attempting to connect "
                           "to management. Aborting.")
            self.aborted = True
            return

        # _alive flag is set in the VPNProcess class.
        if not self._alive:
            logger.debug('Tried to connect to management but process is '
                         'not alive.')
            return
        logger.debug('trying to connect to management')
        if not self.aborted and not self.is_connected():
            self.connect_to_management(self._socket_host, self._socket_port)
            self._reactor.callLater(
                self.CONNECTION_RETRY_TIME,
                self.try_to_connect_to_management, retry + 1)

    def _parse_state_and_notify(self, output):
        """
        Parses the output of the state command and emits state_changed
        signal when the state changes.

        :param output: list of lines that the state command printed as
                       its output
        :type output: list
        """
        for line in output:
            stripped = line.strip()
            if stripped == "END":
                continue
            parts = stripped.split(",")
            if len(parts) < 5:
                continue
            ts, status_step, ok, ip, remote = parts

            state_dict = {
                self.TS_KEY: ts,
                self.STATUS_STEP_KEY: status_step,
                self.OK_KEY: ok,
                self.IP_KEY: ip,
                self.REMOTE_KEY: remote
            }

            if state_dict != self._last_state:
                self.qtsigs.state_changed.emit(state_dict)
                self._last_state = state_dict

    def _parse_status_and_notify(self, output):
        """
        Parses the output of the status command and emits
        status_changed signal when the status changes.

        :param output: list of lines that the status command printed
                       as its output
        :type output: list
        """
        tun_tap_read = ""
        tun_tap_write = ""
        tcp_udp_read = ""
        tcp_udp_write = ""
        auth_read = ""
        for line in output:
            stripped = line.strip()
            if stripped.endswith("STATISTICS") or stripped == "END":
                continue
            parts = stripped.split(",")
            if len(parts) < 2:
                continue
            if parts[0].strip() == "TUN/TAP read bytes":
                tun_tap_read = parts[1]
            elif parts[0].strip() == "TUN/TAP write bytes":
                tun_tap_write = parts[1]
            elif parts[0].strip() == "TCP/UDP read bytes":
                tcp_udp_read = parts[1]
            elif parts[0].strip() == "TCP/UDP write bytes":
                tcp_udp_write = parts[1]
            elif parts[0].strip() == "Auth read bytes":
                auth_read = parts[1]

        status_dict = {
            self.TUNTAP_READ_KEY: tun_tap_read,
            self.TUNTAP_WRITE_KEY: tun_tap_write,
            self.TCPUDP_READ_KEY: tcp_udp_read,
            self.TCPUDP_WRITE_KEY: tcp_udp_write,
            self.AUTH_READ_KEY: auth_read
        }

        if status_dict != self._last_status:
            self.qtsigs.status_changed.emit(status_dict)
            self._last_status = status_dict

    def get_state(self):
        """
        Notifies the gui of the output of the state command over
        the openvpn management interface.
        """
        if self.is_connected():
            return self._parse_state_and_notify(self._send_command("state"))

    def get_status(self):
        """
        Notifies the gui of the output of the status command over
        the openvpn management interface.
        """
        if self.is_connected():
            return self._parse_status_and_notify(self._send_command("status"))

    @property
    def vpn_env(self):
        """
        Return a dict containing the vpn environment to be used.
        """
        return self._launcher.get_vpn_env(self._providerconfig)

    def terminate_openvpn(self, shutdown=False):
        """
        Attempts to terminate openvpn by sending a SIGTERM.
        """
        if self.is_connected():
            self._send_command("signal SIGTERM")
        if shutdown:
            self._cleanup_tempfiles()

    def _cleanup_tempfiles(self):
        """
        Remove all temporal files we might have left behind.

        Iif self.port is 'unix', we have created a temporal socket path that,
        under normal circumstances, we should be able to delete.
        """
        if self._socket_port == "unix":
            logger.debug('cleaning socket file temp folder')
            tempfolder = first(os.path.split(self._socket_host))
            if tempfolder and os.path.isdir(tempfolder):
                try:
                    shutil.rmtree(tempfolder)
                except OSError:
                    logger.error('could not delete tmpfolder %s' % tempfolder)

    def get_openvpn_process(self):
        """
        Looks for openvpn instances running.

        :rtype: process
        """
        openvpn_process = None
        for p in psutil.process_iter():
            try:
                # XXX Not exact!
                # Will give false positives.
                # we should check that cmdline BEGINS
                # with openvpn or with our wrapper
                # (pkexec / osascript / whatever)

                # This needs more work, see #3268, but for the moment
                # we need to be able to filter out arguments in the form
                # --openvpn-foo, since otherwise we are shooting ourselves
                # in the feet.
                if any(map(lambda s: s.find("LEAPOPENVPN") != -1, p.cmdline)):
                    openvpn_process = p
                    break
            except psutil.error.AccessDenied:
                pass
        return openvpn_process

    def stop_if_already_running(self):
        """
        Checks if VPN is already running and tries to stop it.

        Might raise OpenVPNAlreadyRunning.

        :return: True if stopped, False otherwise

        """
        process = self.get_openvpn_process()
        if not process:
            logger.debug('Could not find openvpn process while '
                         'trying to stop it.')
            return

        logger.debug("OpenVPN is already running, trying to stop it...")
        cmdline = process.cmdline

        manag_flag = "--management"
        if isinstance(cmdline, list) and manag_flag in cmdline:
            # we know that our invocation has this distinctive fragment, so
            # we use this fingerprint to tell other invocations apart.
            # this might break if we change the configuration path in the
            # launchers
            smellslikeleap = lambda s: "leap" in s and "providers" in s

            if not any(map(smellslikeleap, cmdline)):
                logger.debug("We cannot stop this instance since we do not "
                             "recognise it as a leap invocation.")
                raise AlienOpenVPNAlreadyRunning

            try:
                index = cmdline.index(manag_flag)
                host = cmdline[index + 1]
                port = cmdline[index + 2]
                logger.debug("Trying to connect to %s:%s"
                             % (host, port))
                self.connect_to_management(host, port)

                # XXX this has a problem with connections to different
                # remotes. So the reconnection will only work when we are
                # terminating instances left running for the same provider.
                # If we are killing an openvpn instance configured for another
                # provider, we will get:
                # TLS Error: local/remote TLS keys are out of sync
                # However, that should be a rare case right now.
                self._send_command("signal SIGTERM")
                self._close_management_socket(announce=True)
            except Exception as e:
                logger.warning("Problem trying to terminate OpenVPN: %r"
                               % (e,))
        else:
            logger.debug("Could not find the expected openvpn command line.")

        process = self.get_openvpn_process()
        if process is None:
            logger.debug("Successfully finished already running "
                         "openvpn process.")
            return True
        else:
            logger.warning("Unable to terminate OpenVPN")
            raise OpenVPNAlreadyRunning


class VPNProcess(protocol.ProcessProtocol, VPNManager):
    """
    A ProcessProtocol class that can be used to spawn a process that will
    launch openvpn and connect to its management interface to control it
    programmatically.
    """

    def __init__(self, eipconfig, providerconfig, socket_host, socket_port,
                 qtsigs, openvpn_verb):
        """
        :param eipconfig: eip configuration object
        :type eipconfig: EIPConfig

        :param providerconfig: provider specific configuration
        :type providerconfig: ProviderConfig

        :param socket_host: either socket path (unix) or socket IP
        :type socket_host: str

        :param socket_port: either string "unix" if it's a unix
                            socket, or port otherwise
        :type socket_port: str

        :param qtsigs: a QObject containing the Qt signals used to notify the
                       UI.
        :type qtsigs: QObject

        :param openvpn_verb: the desired level of verbosity in the
                             openvpn invocation
        :type openvpn_verb: int
        """
        VPNManager.__init__(self, qtsigs=qtsigs)
        leap_assert_type(eipconfig, EIPConfig)
        leap_assert_type(providerconfig, ProviderConfig)
        leap_assert_type(qtsigs, QtCore.QObject)

        #leap_assert(not self.isRunning(), "Starting process more than once!")

        self._eipconfig = eipconfig
        self._providerconfig = providerconfig
        self._socket_host = socket_host
        self._socket_port = socket_port

        self._launcher = get_platform_launcher()

        self._last_state = None
        self._last_status = None
        self._alive = False

        self._openvpn_verb = openvpn_verb

    # processProtocol methods

    def connectionMade(self):
        """
        Called when the connection is made.

        .. seeAlso: `http://twistedmatrix.com/documents/13.0.0/api/twisted.internet.protocol.ProcessProtocol.html` # noqa
        """
        self._alive = True
        self.aborted = False
        self.try_to_connect_to_management(max_retries=10)

    def outReceived(self, data):
        """
        Called when new data is available on stdout.

        :param data: the data read on stdout

        .. seeAlso: `http://twistedmatrix.com/documents/13.0.0/api/twisted.internet.protocol.ProcessProtocol.html` # noqa
        """
        # truncate the newline
        # should send this to the logging window
        vpnlog.info(data[:-1])

    def processExited(self, reason):
        """
        Called when the child process exits.

        .. seeAlso: `http://twistedmatrix.com/documents/13.0.0/api/twisted.internet.protocol.ProcessProtocol.html` # noqa
        """
        exit_code = reason.value.exitCode
        if isinstance(exit_code, int):
            logger.debug("processExited, status %d" % (exit_code,))
        self.qtsigs.process_finished.emit(exit_code)
        self._alive = False

    def processEnded(self, reason):
        """
        Called when the child process exits and all file descriptors associated
        with it have been closed.

        .. seeAlso: `http://twistedmatrix.com/documents/13.0.0/api/twisted.internet.protocol.ProcessProtocol.html` # noqa
        """
        exit_code = reason.value.exitCode
        if isinstance(exit_code, int):
            logger.debug("processEnded, status %d" % (exit_code,))

    # polling

    def pollStatus(self):
        """
        Polls connection status.
        """
        if self._alive:
            self.get_status()

    def pollState(self):
        """
        Polls connection state.
        """
        if self._alive:
            self.get_state()

    # launcher

    def getCommand(self):
        """
        Gets the vpn command from the aproppriate launcher.

        Might throw: VPNLauncherException, OpenVPNNotFoundException.
        """
        cmd = self._launcher.get_vpn_command(
            eipconfig=self._eipconfig,
            providerconfig=self._providerconfig,
            socket_host=self._socket_host,
            socket_port=self._socket_port,
            openvpn_verb=self._openvpn_verb)
        return map(str, cmd)

    # shutdown

    def killProcess(self):
        """
        Sends the KILL signal to the running process.
        """
        try:
            self.transport.signalProcess('KILL')
        except internet_error.ProcessExitedAlready:
            logger.debug('Process Exited Already')