summaryrefslogtreecommitdiff
path: root/src/leap/services/eip/vpnlaunchers.py
blob: 6f277481453d0084ff3855f61a8a0805bcb619a9 (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
# -*- coding: utf-8 -*-
# vpnlaunchers.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/>.

"""
Platform dependant VPN launchers
"""
import os
import platform
import logging
import commands
import getpass
import grp

from abc import ABCMeta, abstractmethod

from leap.config.providerconfig import ProviderConfig
from leap.services.eip.eipconfig import EIPConfig
from leap.util.check import leap_assert, leap_assert_type

logger = logging.getLogger(__name__)


class VPNLauncherException(Exception):
    pass


class VPNLauncher:
    """
    Abstract launcher class
    """

    __metaclass__ = ABCMeta

    # TODO: document parameters
    @abstractmethod
    def get_vpn_command(self, eipconfig=None, providerconfig=None,
                        socket_host=None, socket_port=None):
        """
        Returns the platform dependant vpn launching command

        @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

        @return: A VPN command ready to be launched
        @rtype: list
        """
        return []


def get_platform_launcher():
    launcher = globals()[platform.system() + "VPNLauncher"]
    leap_assert(launcher, "Unimplemented platform launcher: %s" %
                (platform.system(),))
    return launcher()


# Twisted implementation of which
def which(name, flags=os.X_OK, path_extension="/usr/sbin:/sbin"):
    """
    Search PATH for executable files with the given name.

    On newer versions of MS-Windows, the PATHEXT environment variable will be
    set to the list of file extensions for files considered executable. This
    will normally include things like ".EXE". This fuction will also find files
    with the given name ending with any of these extensions.

    On MS-Windows the only flag that has any meaning is os.F_OK. Any other
    flags will be ignored.

    @type name: C{str}
    @param name: The name for which to search.

    @type flags: C{int}
    @param flags: Arguments to L{os.access}.

    @rtype: C{list}
    @param: A list of the full paths to files found, in the
    order in which they were found.
    """

    result = []
    exts = filter(None, os.environ.get('PATHEXT', '').split(os.pathsep))
    path = os.environ.get('PATH', None)
    path += ":" + path_extension
    if path is None:
        return []
    parts = path.split(os.pathsep)
    for p in parts:
        p = os.path.join(p, name)
        if os.access(p, flags):
            result.append(p)
        for e in exts:
            pext = p + e
            if os.access(pext, flags):
                result.append(pext)
    return result


def _is_pkexec_in_system():
    pkexec_path = which('pkexec')
    if len(pkexec_path) == 0:
        return False
    return True


def _has_updown_scripts(path):
    """
    Checks the existence of the up/down scripts
    """
    # XXX should check permissions too
    is_file = os.path.isfile(path)
    if not is_file:
        logger.warning("Could not find up/down scripts. " +
                       "Might produce DNS leaks.")
    return is_file


def _is_auth_agent_running():
    return bool(
        commands.getoutput(
            'ps aux | grep polkit-[g]nome-authentication-agent-1'))


class LinuxVPNLauncher(VPNLauncher):
    """
    VPN launcher for the Linux platform
    """

    PKEXEC_BIN = 'pkexec'
    OPENVPN_BIN = 'openvpn'
    UP_DOWN_SCRIPT = "/etc/leap/resolv-update"
    OPENVPN_DOWN_ROOT = "/usr/lib/openvpn/openvpn-down-root.so"

    def get_vpn_command(self, eipconfig=None, providerconfig=None,
                        socket_host=None, socket_port="unix"):
        """
        Returns the platform dependant vpn launching command

        Might raise VPNException.

        @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

        @return: A VPN command ready to be launched
        @rtype: list
        """
        leap_assert(eipconfig, "We need an eip config")
        leap_assert_type(eipconfig, EIPConfig)
        leap_assert(providerconfig, "We need a provider config")
        leap_assert_type(providerconfig, ProviderConfig)
        leap_assert(socket_host, "We need a socket host!")
        leap_assert(socket_port, "We need a socket port!")

        openvpn_possibilities = which(self.OPENVPN_BIN)
        if len(openvpn_possibilities) == 0:
            raise VPNLauncherException("We couldn't find openvpn")

        openvpn = openvpn_possibilities[0]
        args = []

        if _is_pkexec_in_system():
            if _is_auth_agent_running():
                pkexec_possibilities = which(self.PKEXEC_BIN)
                leap_assert(len(pkexec_possibilities) > 0,
                            "We couldn't find pkexec")
                args.append(openvpn)
                openvpn = pkexec_possibilities[0]
            else:
                logger.warning("No polkit auth agent found. pkexec " +
                               "will use its own auth agent.")
        else:
            logger.warning("System has no pkexec")

        # TODO: handle verbosity

        gateway_ip = str(eipconfig.get_gateway_ip(0))

        logger.debug("Using gateway ip %s" % (gateway_ip,))

        args += [
            '--client',
            '--dev', 'tun',
            '--persist-tun',
            '--persist-key',
            '--remote', gateway_ip, '1194', 'udp',
            '--tls-client',
            '--remote-cert-tls',
            'server'
        ]

        openvpn_configuration = eipconfig.get_openvpn_configuration()
        for key, value in openvpn_configuration.items():
            args += ['--%s' % (key,), value]

        args += [
            '--user', getpass.getuser(),
            '--group', grp.getgrgid(os.getgroups()[-1]).gr_name
        ]

        if socket_port == "unix":
            args += [
                '--management-client-user', getpass.getuser()
            ]

        args += [
            '--management-signal',
            '--management', socket_host, socket_port,
            '--script-security', '2'
        ]

        if _has_updown_scripts(self.UP_DOWN_SCRIPT):
            args += [
                '--up', self.UP_DOWN_SCRIPT,
                '--down', self.UP_DOWN_SCRIPT,
                '--plugin', self.OPENVPN_DOWN_ROOT,
                '\'script_type=down %s\'' % self.UP_DOWN_SCRIPT
            ]

        args += [
            '--cert', eipconfig.get_client_cert_path(providerconfig),
            '--key', eipconfig.get_client_cert_path(providerconfig),
            '--ca', providerconfig.get_ca_cert_path()
        ]

        logger.debug("Running VPN with command:")
        logger.debug("%s %s" % (openvpn, " ".join(args)))

        return [openvpn] + args


if __name__ == "__main__":
    logger = logging.getLogger(name='leap')
    logger.setLevel(logging.DEBUG)
    console = logging.StreamHandler()
    console.setLevel(logging.DEBUG)
    formatter = logging.Formatter(
        '%(asctime)s '
        '- %(name)s - %(levelname)s - %(message)s')
    console.setFormatter(formatter)
    logger.addHandler(console)

    try:
        abs_launcher = VPNLauncher()
    except Exception as e:
        assert isinstance(e, TypeError), "Something went wrong"
        print "Abstract Prefixer class is working as expected"

    vpnlauncher = get_platform_launcher()

    eipconfig = EIPConfig()
    if eipconfig.load("leap/providers/bitmask.net/eip-service.json"):
        provider = ProviderConfig()
        if provider.load("leap/providers/bitmask.net/provider.json"):
            vpnlauncher.get_vpn_command(eipconfig=eipconfig,
                                        providerconfig=provider,
                                        socket_host="/blah")