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  • Committer: Björn Påhlsson
  • Date: 2007-12-11 23:40:35 UTC
  • Revision ID: belorn@braxen-20071211234035-m1nsu41vuzkak69h
Python based server
Added client configfile

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#!/usr/bin/python
2
 
# -*- mode: python; coding: utf-8 -*-
3
 
4
 
# Mandos server - give out binary blobs to connecting clients.
5
 
6
 
# This program is partly derived from an example program for an Avahi
7
 
# service publisher, downloaded from
8
 
# <http://avahi.org/wiki/PythonPublishExample>.  This includes the
9
 
# methods "add" and "remove" in the "AvahiService" class, the
10
 
# "server_state_changed" and "entry_group_state_changed" functions,
11
 
# and some lines in "main".
12
 
13
 
# Everything else is
14
 
# Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
15
 
16
 
# This program is free software: you can redistribute it and/or modify
17
 
# it under the terms of the GNU General Public License as published by
18
 
# the Free Software Foundation, either version 3 of the License, or
19
 
# (at your option) any later version.
20
 
#
21
 
#     This program is distributed in the hope that it will be useful,
22
 
#     but WITHOUT ANY WARRANTY; without even the implied warranty of
23
 
#     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24
 
#     GNU General Public License for more details.
25
 
26
 
# You should have received a copy of the GNU General Public License
27
 
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
28
 
29
 
# Contact the authors at <mandos@fukt.bsnet.se>.
30
 
31
 
 
32
 
from __future__ import division
33
2
 
34
3
import SocketServer
35
4
import socket
40
9
import gnutls.crypto
41
10
import gnutls.connection
42
11
import gnutls.errors
43
 
import gnutls.library.functions
44
 
import gnutls.library.constants
45
 
import gnutls.library.types
46
12
import ConfigParser
47
 
import sys
48
 
import re
49
 
import os
50
 
import signal
51
 
from sets import Set
52
 
import subprocess
53
 
import atexit
54
 
import stat
55
 
import logging
56
 
import logging.handlers
57
 
 
58
 
import dbus
59
 
import gobject
60
 
import avahi
61
 
from dbus.mainloop.glib import DBusGMainLoop
62
 
import ctypes
63
 
 
64
 
version = "1.0"
65
 
 
66
 
logger = logging.Logger('mandos')
67
 
syslogger = logging.handlers.SysLogHandler\
68
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
69
 
             address = "/dev/log")
70
 
syslogger.setFormatter(logging.Formatter\
71
 
                        ('Mandos: %(levelname)s: %(message)s'))
72
 
logger.addHandler(syslogger)
73
 
 
74
 
console = logging.StreamHandler()
75
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
76
 
                                       ' %(message)s'))
77
 
logger.addHandler(console)
78
 
 
79
 
class AvahiError(Exception):
80
 
    def __init__(self, value):
81
 
        self.value = value
82
 
    def __str__(self):
83
 
        return repr(self.value)
84
 
 
85
 
class AvahiServiceError(AvahiError):
86
 
    pass
87
 
 
88
 
class AvahiGroupError(AvahiError):
89
 
    pass
90
 
 
91
 
 
92
 
class AvahiService(object):
93
 
    """An Avahi (Zeroconf) service.
94
 
    Attributes:
95
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
96
 
               Used to optionally bind to the specified interface.
97
 
    name: string; Example: 'Mandos'
98
 
    type: string; Example: '_mandos._tcp'.
99
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
100
 
    port: integer; what port to announce
101
 
    TXT: list of strings; TXT record for the service
102
 
    domain: string; Domain to publish on, default to .local if empty.
103
 
    host: string; Host to publish records for, default is localhost
104
 
    max_renames: integer; maximum number of renames
105
 
    rename_count: integer; counter so we only rename after collisions
106
 
                  a sensible number of times
107
 
    """
108
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
109
 
                 type = None, port = None, TXT = None, domain = "",
110
 
                 host = "", max_renames = 32768):
111
 
        self.interface = interface
112
 
        self.name = name
113
 
        self.type = type
114
 
        self.port = port
115
 
        if TXT is None:
116
 
            self.TXT = []
117
 
        else:
118
 
            self.TXT = TXT
119
 
        self.domain = domain
120
 
        self.host = host
121
 
        self.rename_count = 0
122
 
        self.max_renames = max_renames
123
 
    def rename(self):
124
 
        """Derived from the Avahi example code"""
125
 
        if self.rename_count >= self.max_renames:
126
 
            logger.critical(u"No suitable service name found after %i"
127
 
                            u" retries, exiting.", rename_count)
128
 
            raise AvahiServiceError("Too many renames")
129
 
        self.name = server.GetAlternativeServiceName(self.name)
130
 
        logger.info(u"Changing name to %r ...", str(self.name))
131
 
        syslogger.setFormatter(logging.Formatter\
132
 
                               ('Mandos (%s): %%(levelname)s:'
133
 
                               ' %%(message)s' % self.name))
134
 
        self.remove()
135
 
        self.add()
136
 
        self.rename_count += 1
137
 
    def remove(self):
138
 
        """Derived from the Avahi example code"""
139
 
        if group is not None:
140
 
            group.Reset()
141
 
    def add(self):
142
 
        """Derived from the Avahi example code"""
143
 
        global group
144
 
        if group is None:
145
 
            group = dbus.Interface\
146
 
                    (bus.get_object(avahi.DBUS_NAME,
147
 
                                    server.EntryGroupNew()),
148
 
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
149
 
            group.connect_to_signal('StateChanged',
150
 
                                    entry_group_state_changed)
151
 
        logger.debug(u"Adding service '%s' of type '%s' ...",
152
 
                     service.name, service.type)
153
 
        group.AddService(
154
 
                self.interface,         # interface
155
 
                avahi.PROTO_INET6,      # protocol
156
 
                dbus.UInt32(0),         # flags
157
 
                self.name, self.type,
158
 
                self.domain, self.host,
159
 
                dbus.UInt16(self.port),
160
 
                avahi.string_array_to_txt_array(self.TXT))
161
 
        group.Commit()
162
 
 
163
 
# From the Avahi example code:
164
 
group = None                            # our entry group
165
 
# End of Avahi example code
166
 
 
167
13
 
168
14
class Client(object):
169
 
    """A representation of a client host served by this server.
170
 
    Attributes:
171
 
    name:      string; from the config file, used in log messages
172
 
    fingerprint: string (40 or 32 hexadecimal digits); used to
173
 
                 uniquely identify the client
174
 
    secret:    bytestring; sent verbatim (over TLS) to client
175
 
    host:      string; available for use by the checker command
176
 
    created:   datetime.datetime(); object creation, not client host
177
 
    last_checked_ok: datetime.datetime() or None if not yet checked OK
178
 
    timeout:   datetime.timedelta(); How long from last_checked_ok
179
 
                                     until this client is invalid
180
 
    interval:  datetime.timedelta(); How often to start a new checker
181
 
    stop_hook: If set, called by stop() as stop_hook(self)
182
 
    checker:   subprocess.Popen(); a running checker process used
183
 
                                   to see if the client lives.
184
 
                                   'None' if no process is running.
185
 
    checker_initiator_tag: a gobject event source tag, or None
186
 
    stop_initiator_tag:    - '' -
187
 
    checker_callback_tag:  - '' -
188
 
    checker_command: string; External command which is run to check if
189
 
                     client lives.  %() expansions are done at
190
 
                     runtime with vars(self) as dict, so that for
191
 
                     instance %(name)s can be used in the command.
192
 
    Private attibutes:
193
 
    _timeout: Real variable for 'timeout'
194
 
    _interval: Real variable for 'interval'
195
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
196
 
    _interval_milliseconds: - '' -
197
 
    """
198
 
    def _set_timeout(self, timeout):
199
 
        "Setter function for 'timeout' attribute"
200
 
        self._timeout = timeout
201
 
        self._timeout_milliseconds = ((self.timeout.days
202
 
                                       * 24 * 60 * 60 * 1000)
203
 
                                      + (self.timeout.seconds * 1000)
204
 
                                      + (self.timeout.microseconds
205
 
                                         // 1000))
206
 
    timeout = property(lambda self: self._timeout,
207
 
                       _set_timeout)
208
 
    del _set_timeout
209
 
    def _set_interval(self, interval):
210
 
        "Setter function for 'interval' attribute"
211
 
        self._interval = interval
212
 
        self._interval_milliseconds = ((self.interval.days
213
 
                                        * 24 * 60 * 60 * 1000)
214
 
                                       + (self.interval.seconds
215
 
                                          * 1000)
216
 
                                       + (self.interval.microseconds
217
 
                                          // 1000))
218
 
    interval = property(lambda self: self._interval,
219
 
                        _set_interval)
220
 
    del _set_interval
221
 
    def __init__(self, name = None, stop_hook=None, config={}):
222
 
        """Note: the 'checker' key in 'config' sets the
223
 
        'checker_command' attribute and *not* the 'checker'
224
 
        attribute."""
 
15
    def __init__(self, name=None, dn=None, password=None,
 
16
                 passfile=None, fqdn=None, timeout=None,
 
17
                 interval=-1):
225
18
        self.name = name
226
 
        logger.debug(u"Creating client %r", self.name)
227
 
        # Uppercase and remove spaces from fingerprint for later
228
 
        # comparison purposes with return value from the fingerprint()
229
 
        # function
230
 
        self.fingerprint = config["fingerprint"].upper()\
231
 
                           .replace(u" ", u"")
232
 
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
233
 
        if "secret" in config:
234
 
            self.secret = config["secret"].decode(u"base64")
235
 
        elif "secfile" in config:
236
 
            sf = open(config["secfile"])
237
 
            self.secret = sf.read()
238
 
            sf.close()
239
 
        else:
240
 
            raise TypeError(u"No secret or secfile for client %s"
241
 
                            % self.name)
242
 
        self.host = config.get("host", "")
243
 
        self.created = datetime.datetime.now()
244
 
        self.last_checked_ok = None
245
 
        self.timeout = string_to_delta(config["timeout"])
246
 
        self.interval = string_to_delta(config["interval"])
247
 
        self.stop_hook = stop_hook
248
 
        self.checker = None
249
 
        self.checker_initiator_tag = None
250
 
        self.stop_initiator_tag = None
251
 
        self.checker_callback_tag = None
252
 
        self.check_command = config["checker"]
253
 
    def start(self):
254
 
        """Start this client's checker and timeout hooks"""
255
 
        # Schedule a new checker to be started an 'interval' from now,
256
 
        # and every interval from then on.
257
 
        self.checker_initiator_tag = gobject.timeout_add\
258
 
                                     (self._interval_milliseconds,
259
 
                                      self.start_checker)
260
 
        # Also start a new checker *right now*.
261
 
        self.start_checker()
262
 
        # Schedule a stop() when 'timeout' has passed
263
 
        self.stop_initiator_tag = gobject.timeout_add\
264
 
                                  (self._timeout_milliseconds,
265
 
                                   self.stop)
266
 
    def stop(self):
267
 
        """Stop this client.
268
 
        The possibility that a client might be restarted is left open,
269
 
        but not currently used."""
270
 
        # If this client doesn't have a secret, it is already stopped.
271
 
        if hasattr(self, "secret") and self.secret:
272
 
            logger.info(u"Stopping client %s", self.name)
273
 
            self.secret = None
274
 
        else:
275
 
            return False
276
 
        if getattr(self, "stop_initiator_tag", False):
277
 
            gobject.source_remove(self.stop_initiator_tag)
278
 
            self.stop_initiator_tag = None
279
 
        if getattr(self, "checker_initiator_tag", False):
280
 
            gobject.source_remove(self.checker_initiator_tag)
281
 
            self.checker_initiator_tag = None
282
 
        self.stop_checker()
283
 
        if self.stop_hook:
284
 
            self.stop_hook(self)
285
 
        # Do not run this again if called by a gobject.timeout_add
286
 
        return False
287
 
    def __del__(self):
288
 
        self.stop_hook = None
289
 
        self.stop()
290
 
    def checker_callback(self, pid, condition):
291
 
        """The checker has completed, so take appropriate actions."""
292
 
        now = datetime.datetime.now()
293
 
        self.checker_callback_tag = None
294
 
        self.checker = None
295
 
        if os.WIFEXITED(condition) \
296
 
               and (os.WEXITSTATUS(condition) == 0):
297
 
            logger.info(u"Checker for %(name)s succeeded",
298
 
                        vars(self))
299
 
            self.last_checked_ok = now
300
 
            gobject.source_remove(self.stop_initiator_tag)
301
 
            self.stop_initiator_tag = gobject.timeout_add\
302
 
                                      (self._timeout_milliseconds,
303
 
                                       self.stop)
304
 
        elif not os.WIFEXITED(condition):
305
 
            logger.warning(u"Checker for %(name)s crashed?",
306
 
                           vars(self))
307
 
        else:
308
 
            logger.info(u"Checker for %(name)s failed",
309
 
                        vars(self))
310
 
    def start_checker(self):
311
 
        """Start a new checker subprocess if one is not running.
312
 
        If a checker already exists, leave it running and do
313
 
        nothing."""
314
 
        # The reason for not killing a running checker is that if we
315
 
        # did that, then if a checker (for some reason) started
316
 
        # running slowly and taking more than 'interval' time, the
317
 
        # client would inevitably timeout, since no checker would get
318
 
        # a chance to run to completion.  If we instead leave running
319
 
        # checkers alone, the checker would have to take more time
320
 
        # than 'timeout' for the client to be declared invalid, which
321
 
        # is as it should be.
322
 
        if self.checker is None:
323
 
            try:
324
 
                # In case check_command has exactly one % operator
325
 
                command = self.check_command % self.host
326
 
            except TypeError:
327
 
                # Escape attributes for the shell
328
 
                escaped_attrs = dict((key, re.escape(str(val)))
329
 
                                     for key, val in
330
 
                                     vars(self).iteritems())
331
 
                try:
332
 
                    command = self.check_command % escaped_attrs
333
 
                except TypeError, error:
334
 
                    logger.error(u'Could not format string "%s":'
335
 
                                 u' %s', self.check_command, error)
336
 
                    return True # Try again later
337
 
            try:
338
 
                logger.info(u"Starting checker %r for %s",
339
 
                            command, self.name)
340
 
                # We don't need to redirect stdout and stderr, since
341
 
                # in normal mode, that is already done by daemon(),
342
 
                # and in debug mode we don't want to.  (Stdin is
343
 
                # always replaced by /dev/null.)
344
 
                self.checker = subprocess.Popen(command,
345
 
                                                close_fds=True,
346
 
                                                shell=True, cwd="/")
347
 
                self.checker_callback_tag = gobject.child_watch_add\
348
 
                                            (self.checker.pid,
349
 
                                             self.checker_callback)
350
 
            except OSError, error:
351
 
                logger.error(u"Failed to start subprocess: %s",
352
 
                             error)
353
 
        # Re-run this periodically if run by gobject.timeout_add
354
 
        return True
355
 
    def stop_checker(self):
356
 
        """Force the checker process, if any, to stop."""
357
 
        if self.checker_callback_tag:
358
 
            gobject.source_remove(self.checker_callback_tag)
359
 
            self.checker_callback_tag = None
360
 
        if getattr(self, "checker", None) is None:
361
 
            return
362
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
 
19
        self.dn = dn
 
20
        if password:
 
21
            self.password = password
 
22
        elif passfile:
 
23
            self.password = open(passfile).readall()
 
24
        else:
 
25
            print "No Password or Passfile in client config file"
 
26
            # raise RuntimeError XXX
 
27
            self.password = "gazonk"
 
28
        self.fqdn = fqdn
 
29
        # self.created = ...
 
30
        self.last_seen = None
 
31
        if timeout is None:
 
32
            timeout = self.server.options.timeout
 
33
        self.timeout = timeout
 
34
        if interval == -1:
 
35
            interval = self.server.options.interval
 
36
        self.interval = interval
 
37
 
 
38
def server_bind(self):
 
39
    if self.options.interface:
 
40
        if not hasattr(socket, "SO_BINDTODEVICE"):
 
41
            # From /usr/include/asm-i486/socket.h
 
42
            socket.SO_BINDTODEVICE = 25
363
43
        try:
364
 
            os.kill(self.checker.pid, signal.SIGTERM)
365
 
            #os.sleep(0.5)
366
 
            #if self.checker.poll() is None:
367
 
            #    os.kill(self.checker.pid, signal.SIGKILL)
368
 
        except OSError, error:
369
 
            if error.errno != errno.ESRCH: # No such process
370
 
                raise
371
 
        self.checker = None
372
 
    def still_valid(self):
373
 
        """Has the timeout not yet passed for this client?"""
374
 
        now = datetime.datetime.now()
375
 
        if self.last_checked_ok is None:
376
 
            return now < (self.created + self.timeout)
377
 
        else:
378
 
            return now < (self.last_checked_ok + self.timeout)
379
 
 
380
 
 
381
 
def peer_certificate(session):
382
 
    "Return the peer's OpenPGP certificate as a bytestring"
383
 
    # If not an OpenPGP certificate...
384
 
    if gnutls.library.functions.gnutls_certificate_type_get\
385
 
            (session._c_object) \
386
 
           != gnutls.library.constants.GNUTLS_CRT_OPENPGP:
387
 
        # ...do the normal thing
388
 
        return session.peer_certificate
389
 
    list_size = ctypes.c_uint()
390
 
    cert_list = gnutls.library.functions.gnutls_certificate_get_peers\
391
 
        (session._c_object, ctypes.byref(list_size))
392
 
    if list_size.value == 0:
393
 
        return None
394
 
    cert = cert_list[0]
395
 
    return ctypes.string_at(cert.data, cert.size)
396
 
 
397
 
 
398
 
def fingerprint(openpgp):
399
 
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
400
 
    # New GnuTLS "datum" with the OpenPGP public key
401
 
    datum = gnutls.library.types.gnutls_datum_t\
402
 
        (ctypes.cast(ctypes.c_char_p(openpgp),
403
 
                     ctypes.POINTER(ctypes.c_ubyte)),
404
 
         ctypes.c_uint(len(openpgp)))
405
 
    # New empty GnuTLS certificate
406
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
407
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
408
 
        (ctypes.byref(crt))
409
 
    # Import the OpenPGP public key into the certificate
410
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
411
 
                    (crt, ctypes.byref(datum),
412
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
413
 
    # Verify the self signature in the key
414
 
    crtverify = ctypes.c_uint();
415
 
    gnutls.library.functions.gnutls_openpgp_crt_verify_self\
416
 
        (crt, ctypes.c_uint(0), ctypes.byref(crtverify))
417
 
    if crtverify.value != 0:
418
 
        tmp = open("/tmp/tmp.gpg", "w")
419
 
        tmp.write(openpgp)
420
 
        tmp.close()
421
 
        gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
422
 
        raise gnutls.errors.CertificateSecurityError("Verify failed")
423
 
    # New buffer for the fingerprint
424
 
    buffer = ctypes.create_string_buffer(20)
425
 
    buffer_length = ctypes.c_size_t()
426
 
    # Get the fingerprint from the certificate into the buffer
427
 
    gnutls.library.functions.gnutls_openpgp_crt_get_fingerprint\
428
 
        (crt, ctypes.byref(buffer), ctypes.byref(buffer_length))
429
 
    # Deinit the certificate
430
 
    gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
431
 
    # Convert the buffer to a Python bytestring
432
 
    fpr = ctypes.string_at(buffer, buffer_length.value)
433
 
    # Convert the bytestring to hexadecimal notation
434
 
    hex_fpr = u''.join(u"%02X" % ord(char) for char in fpr)
435
 
    return hex_fpr
 
44
            self.socket.setsockopt(socket.SOL_SOCKET,
 
45
                                   socket.SO_BINDTODEVICE,
 
46
                                   self.options.interface)
 
47
        except socket.error, error:
 
48
            if error[0] == errno.EPERM:
 
49
                print "Warning: Denied permission to bind to interface", \
 
50
                      self.options.interface
 
51
            else:
 
52
                raise error
 
53
    return super(type(self), self).server_bind()
 
54
 
 
55
 
 
56
def init_with_options(self, *args, **kwargs):
 
57
    if "options" in kwargs:
 
58
        self.options = kwargs["options"]
 
59
        del kwargs["options"]
 
60
    if "clients" in kwargs:
 
61
        self.clients = kwargs["clients"]
 
62
        del kwargs["clients"]
 
63
    if "credentials" in kwargs:
 
64
        self.credentials = kwargs["credentials"]
 
65
        del kwargs["credentials"]
 
66
    return super(type(self), self).__init__(*args, **kwargs)
 
67
 
 
68
 
 
69
class udp_handler(SocketServer.DatagramRequestHandler, object):
 
70
    def handle(self):
 
71
        self.wfile.write("Polo")
 
72
        print "UDP request answered"
 
73
 
 
74
 
 
75
class IPv6_UDPServer(SocketServer.UDPServer, object):
 
76
    __init__ = init_with_options
 
77
    address_family = socket.AF_INET6
 
78
    allow_reuse_address = True
 
79
    server_bind = server_bind
 
80
    def verify_request(self, request, client_address):
 
81
        print "UDP request came"
 
82
        return request[0] == "Marco"
436
83
 
437
84
 
438
85
class tcp_handler(SocketServer.BaseRequestHandler, object):
439
 
    """A TCP request handler class.
440
 
    Instantiated by IPv6_TCPServer for each request to handle it.
441
 
    Note: This will run in its own forked process."""
442
 
    
443
86
    def handle(self):
444
 
        logger.info(u"TCP connection from: %s",
445
 
                     unicode(self.client_address))
446
 
        session = gnutls.connection.ClientSession\
447
 
                  (self.request, gnutls.connection.X509Credentials())
448
 
        
449
 
        line = self.request.makefile().readline()
450
 
        logger.debug(u"Protocol version: %r", line)
451
 
        try:
452
 
            if int(line.strip().split()[0]) > 1:
453
 
                raise RuntimeError
454
 
        except (ValueError, IndexError, RuntimeError), error:
455
 
            logger.error(u"Unknown protocol version: %s", error)
456
 
            return
457
 
        
458
 
        # Note: gnutls.connection.X509Credentials is really a generic
459
 
        # GnuTLS certificate credentials object so long as no X.509
460
 
        # keys are added to it.  Therefore, we can use it here despite
461
 
        # using OpenPGP certificates.
462
 
        
463
 
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
464
 
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
465
 
        #                "+DHE-DSS"))
466
 
        priority = "NORMAL"             # Fallback default, since this
467
 
                                        # MUST be set.
468
 
        if self.server.settings["priority"]:
469
 
            priority = self.server.settings["priority"]
470
 
        gnutls.library.functions.gnutls_priority_set_direct\
471
 
            (session._c_object, priority, None);
472
 
        
473
 
        try:
474
 
            session.handshake()
475
 
        except gnutls.errors.GNUTLSError, error:
476
 
            logger.warning(u"Handshake failed: %s", error)
477
 
            # Do not run session.bye() here: the session is not
478
 
            # established.  Just abandon the request.
479
 
            return
480
 
        try:
481
 
            fpr = fingerprint(peer_certificate(session))
482
 
        except (TypeError, gnutls.errors.GNUTLSError), error:
483
 
            logger.warning(u"Bad certificate: %s", error)
484
 
            session.bye()
485
 
            return
486
 
        logger.debug(u"Fingerprint: %s", fpr)
487
 
        client = None
488
 
        for c in self.server.clients:
489
 
            if c.fingerprint == fpr:
490
 
                client = c
491
 
                break
492
 
        if not client:
493
 
            logger.warning(u"Client not found for fingerprint: %s",
494
 
                           fpr)
495
 
            session.bye()
496
 
            return
497
 
        # Have to check if client.still_valid(), since it is possible
498
 
        # that the client timed out while establishing the GnuTLS
499
 
        # session.
500
 
        if not client.still_valid():
501
 
            logger.warning(u"Client %(name)s is invalid",
502
 
                           vars(client))
503
 
            session.bye()
504
 
            return
505
 
        sent_size = 0
506
 
        while sent_size < len(client.secret):
507
 
            sent = session.send(client.secret[sent_size:])
508
 
            logger.debug(u"Sent: %d, remaining: %d",
509
 
                         sent, len(client.secret)
510
 
                         - (sent_size + sent))
511
 
            sent_size += sent
 
87
        print "TCP request came"
 
88
        print "Request:", self.request
 
89
        print "Client Address:", self.client_address
 
90
        print "Server:", self.server
 
91
        session = gnutls.connection.ServerSession(self.request,
 
92
                                                  self.server.credentials)
 
93
        session.handshake()
 
94
        if session.peer_certificate:
 
95
            print "DN:", session.peer_certificate.subject
 
96
        try:
 
97
            session.verify_peer()
 
98
        except gnutls.errors.CertificateError, error:
 
99
            print "Verify failed", error
 
100
            session.bye()
 
101
            return
 
102
        try:
 
103
            session.send(dict((client.dn, client.password)
 
104
                              for client in self.server.clients)
 
105
                         [session.peer_certificate.subject])
 
106
        except KeyError:
 
107
            session.send("gazonk")
 
108
            # Log maybe? XXX
512
109
        session.bye()
513
110
 
514
 
 
515
111
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
516
 
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
517
 
    Attributes:
518
 
        settings:       Server settings
519
 
        clients:        Set() of Client objects
520
 
    """
 
112
    __init__ = init_with_options
521
113
    address_family = socket.AF_INET6
522
 
    def __init__(self, *args, **kwargs):
523
 
        if "settings" in kwargs:
524
 
            self.settings = kwargs["settings"]
525
 
            del kwargs["settings"]
526
 
        if "clients" in kwargs:
527
 
            self.clients = kwargs["clients"]
528
 
            del kwargs["clients"]
529
 
        return super(type(self), self).__init__(*args, **kwargs)
530
 
    def server_bind(self):
531
 
        """This overrides the normal server_bind() function
532
 
        to bind to an interface if one was specified, and also NOT to
533
 
        bind to an address or port if they were not specified."""
534
 
        if self.settings["interface"]:
535
 
            # 25 is from /usr/include/asm-i486/socket.h
536
 
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
537
 
            try:
538
 
                self.socket.setsockopt(socket.SOL_SOCKET,
539
 
                                       SO_BINDTODEVICE,
540
 
                                       self.settings["interface"])
541
 
            except socket.error, error:
542
 
                if error[0] == errno.EPERM:
543
 
                    logger.error(u"No permission to"
544
 
                                 u" bind to interface %s",
545
 
                                 self.settings["interface"])
546
 
                else:
547
 
                    raise error
548
 
        # Only bind(2) the socket if we really need to.
549
 
        if self.server_address[0] or self.server_address[1]:
550
 
            if not self.server_address[0]:
551
 
                in6addr_any = "::"
552
 
                self.server_address = (in6addr_any,
553
 
                                       self.server_address[1])
554
 
            elif not self.server_address[1]:
555
 
                self.server_address = (self.server_address[0],
556
 
                                       0)
557
 
#                 if self.settings["interface"]:
558
 
#                     self.server_address = (self.server_address[0],
559
 
#                                            0, # port
560
 
#                                            0, # flowinfo
561
 
#                                            if_nametoindex
562
 
#                                            (self.settings
563
 
#                                             ["interface"]))
564
 
            return super(type(self), self).server_bind()
565
 
 
566
 
 
567
 
def string_to_delta(interval):
568
 
    """Parse a string and return a datetime.timedelta
569
 
 
570
 
    >>> string_to_delta('7d')
571
 
    datetime.timedelta(7)
572
 
    >>> string_to_delta('60s')
573
 
    datetime.timedelta(0, 60)
574
 
    >>> string_to_delta('60m')
575
 
    datetime.timedelta(0, 3600)
576
 
    >>> string_to_delta('24h')
577
 
    datetime.timedelta(1)
578
 
    >>> string_to_delta(u'1w')
579
 
    datetime.timedelta(7)
580
 
    >>> string_to_delta('5m 30s')
581
 
    datetime.timedelta(0, 330)
582
 
    """
583
 
    timevalue = datetime.timedelta(0)
584
 
    for s in interval.split():
585
 
        try:
586
 
            suffix=unicode(s[-1])
587
 
            value=int(s[:-1])
588
 
            if suffix == u"d":
589
 
                delta = datetime.timedelta(value)
590
 
            elif suffix == u"s":
591
 
                delta = datetime.timedelta(0, value)
592
 
            elif suffix == u"m":
593
 
                delta = datetime.timedelta(0, 0, 0, 0, value)
594
 
            elif suffix == u"h":
595
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, value)
596
 
            elif suffix == u"w":
597
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
598
 
            else:
599
 
                raise ValueError
600
 
        except (ValueError, IndexError):
601
 
            raise ValueError
602
 
        timevalue += delta
603
 
    return timevalue
604
 
 
605
 
 
606
 
def server_state_changed(state):
607
 
    """Derived from the Avahi example code"""
608
 
    if state == avahi.SERVER_COLLISION:
609
 
        logger.error(u"Server name collision")
610
 
        service.remove()
611
 
    elif state == avahi.SERVER_RUNNING:
612
 
        service.add()
613
 
 
614
 
 
615
 
def entry_group_state_changed(state, error):
616
 
    """Derived from the Avahi example code"""
617
 
    logger.debug(u"state change: %i", state)
618
 
    
619
 
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
620
 
        logger.debug(u"Service established.")
621
 
    elif state == avahi.ENTRY_GROUP_COLLISION:
622
 
        logger.warning(u"Service name collision.")
623
 
        service.rename()
624
 
    elif state == avahi.ENTRY_GROUP_FAILURE:
625
 
        logger.critical(u"Error in group state changed %s",
626
 
                        unicode(error))
627
 
        raise AvahiGroupError("State changed: %s", str(error))
628
 
 
629
 
def if_nametoindex(interface):
630
 
    """Call the C function if_nametoindex(), or equivalent"""
631
 
    global if_nametoindex
632
 
    try:
633
 
        if "ctypes.util" not in sys.modules:
634
 
            import ctypes.util
635
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
636
 
            (ctypes.util.find_library("c")).if_nametoindex
637
 
    except (OSError, AttributeError):
638
 
        if "struct" not in sys.modules:
639
 
            import struct
640
 
        if "fcntl" not in sys.modules:
641
 
            import fcntl
642
 
        def if_nametoindex(interface):
643
 
            "Get an interface index the hard way, i.e. using fcntl()"
644
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
645
 
            s = socket.socket()
646
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
647
 
                                struct.pack("16s16x", interface))
648
 
            s.close()
649
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
650
 
            return interface_index
651
 
    return if_nametoindex(interface)
652
 
 
653
 
 
654
 
def daemon(nochdir = False, noclose = False):
655
 
    """See daemon(3).  Standard BSD Unix function.
656
 
    This should really exist as os.daemon, but it doesn't (yet)."""
657
 
    if os.fork():
658
 
        sys.exit()
659
 
    os.setsid()
660
 
    if not nochdir:
661
 
        os.chdir("/")
662
 
    if os.fork():
663
 
        sys.exit()
664
 
    if not noclose:
665
 
        # Close all standard open file descriptors
666
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
667
 
        if not stat.S_ISCHR(os.fstat(null).st_mode):
668
 
            raise OSError(errno.ENODEV,
669
 
                          "/dev/null not a character device")
670
 
        os.dup2(null, sys.stdin.fileno())
671
 
        os.dup2(null, sys.stdout.fileno())
672
 
        os.dup2(null, sys.stderr.fileno())
673
 
        if null > 2:
674
 
            os.close(null)
675
 
 
 
114
    allow_reuse_address = True
 
115
    request_queue_size = 1024
 
116
    server_bind = server_bind
 
117
 
 
118
 
 
119
in6addr_any = "::"
 
120
 
 
121
cred = None
676
122
 
677
123
def main():
678
 
    global main_loop_started
679
 
    main_loop_started = False
680
 
    
681
 
    parser = OptionParser(version = "%%prog %s" % version)
 
124
    parser = OptionParser()
682
125
    parser.add_option("-i", "--interface", type="string",
683
 
                      metavar="IF", help="Bind to interface IF")
684
 
    parser.add_option("-a", "--address", type="string",
685
 
                      help="Address to listen for requests on")
686
 
    parser.add_option("-p", "--port", type="int",
 
126
                      default="eth0", metavar="IF",
 
127
                      help="Interface to bind to")
 
128
    parser.add_option("--cert", type="string", default="cert.pem",
 
129
                      metavar="FILE",
 
130
                      help="Public key certificate to use")
 
131
    parser.add_option("--key", type="string", default="key.pem",
 
132
                      metavar="FILE",
 
133
                      help="Private key to use")
 
134
    parser.add_option("--ca", type="string", default="ca.pem",
 
135
                      metavar="FILE",
 
136
                      help="Certificate Authority certificate to use")
 
137
    parser.add_option("--crl", type="string", default="crl.pem",
 
138
                      metavar="FILE",
 
139
                      help="Certificate Revokation List to use")
 
140
    parser.add_option("-p", "--port", type="int", default=49001,
687
141
                      help="Port number to receive requests on")
688
 
    parser.add_option("--check", action="store_true", default=False,
689
 
                      help="Run self-test")
690
 
    parser.add_option("--debug", action="store_true",
691
 
                      help="Debug mode; run in foreground and log to"
692
 
                      " terminal")
693
 
    parser.add_option("--priority", type="string", help="GnuTLS"
694
 
                      " priority string (see GnuTLS documentation)")
695
 
    parser.add_option("--servicename", type="string", metavar="NAME",
696
 
                      help="Zeroconf service name")
697
 
    parser.add_option("--configdir", type="string",
698
 
                      default="/etc/mandos", metavar="DIR",
699
 
                      help="Directory to search for configuration"
700
 
                      " files")
 
142
    parser.add_option("--dh", type="int", metavar="BITS",
 
143
                      help="DH group to use")
 
144
    parser.add_option("-t", "--timeout", type="string", # Parsed later
 
145
                      default="15m",
 
146
                      help="Amount of downtime allowed for clients")
701
147
    (options, args) = parser.parse_args()
702
148
    
703
 
    if options.check:
704
 
        import doctest
705
 
        doctest.testmod()
706
 
        sys.exit()
707
 
    
708
 
    # Default values for config file for server-global settings
709
 
    server_defaults = { "interface": "",
710
 
                        "address": "",
711
 
                        "port": "",
712
 
                        "debug": "False",
713
 
                        "priority":
714
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
715
 
                        "servicename": "Mandos",
716
 
                        }
717
 
    
718
 
    # Parse config file for server-global settings
719
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
720
 
    del server_defaults
721
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
722
 
    # Convert the SafeConfigParser object to a dict
723
 
    server_settings = server_config.defaults()
724
 
    # Use getboolean on the boolean config option
725
 
    server_settings["debug"] = server_config.getboolean\
726
 
                               ("DEFAULT", "debug")
727
 
    del server_config
728
 
    
729
 
    # Override the settings from the config file with command line
730
 
    # options, if set.
731
 
    for option in ("interface", "address", "port", "debug",
732
 
                   "priority", "servicename", "configdir"):
733
 
        value = getattr(options, option)
734
 
        if value is not None:
735
 
            server_settings[option] = value
736
 
    del options
737
 
    # Now we have our good server settings in "server_settings"
738
 
    
739
 
    debug = server_settings["debug"]
740
 
    
741
 
    if not debug:
742
 
        syslogger.setLevel(logging.WARNING)
743
 
        console.setLevel(logging.WARNING)
744
 
    
745
 
    if server_settings["servicename"] != "Mandos":
746
 
        syslogger.setFormatter(logging.Formatter\
747
 
                               ('Mandos (%s): %%(levelname)s:'
748
 
                                ' %%(message)s'
749
 
                                % server_settings["servicename"]))
750
 
    
751
 
    # Parse config file with clients
752
 
    client_defaults = { "timeout": "1h",
753
 
                        "interval": "5m",
754
 
                        "checker": "fping -q -- %(host)s",
755
 
                        "host": "",
756
 
                        }
757
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
758
 
    client_config.read(os.path.join(server_settings["configdir"],
759
 
                                    "clients.conf"))
760
 
    
761
 
    global service
762
 
    service = AvahiService(name = server_settings["servicename"],
763
 
                           type = "_mandos._tcp", );
764
 
    if server_settings["interface"]:
765
 
        service.interface = if_nametoindex(server_settings["interface"])
766
 
    
767
 
    global main_loop
768
 
    global bus
769
 
    global server
770
 
    # From the Avahi example code
771
 
    DBusGMainLoop(set_as_default=True )
772
 
    main_loop = gobject.MainLoop()
773
 
    bus = dbus.SystemBus()
774
 
    server = dbus.Interface(
775
 
            bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
776
 
            avahi.DBUS_INTERFACE_SERVER )
777
 
    # End of Avahi example code
778
 
    
779
 
    clients = Set()
780
 
    def remove_from_clients(client):
781
 
        clients.remove(client)
782
 
        if not clients:
783
 
            logger.critical(u"No clients left, exiting")
784
 
            sys.exit()
785
 
    
786
 
    clients.update(Set(Client(name = section,
787
 
                              stop_hook = remove_from_clients,
788
 
                              config
789
 
                              = dict(client_config.items(section)))
790
 
                       for section in client_config.sections()))
791
 
    if not clients:
792
 
        logger.critical(u"No clients defined")
793
 
        sys.exit(1)
794
 
    
795
 
    if debug:
796
 
        # Redirect stdin so all checkers get /dev/null
797
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
798
 
        os.dup2(null, sys.stdin.fileno())
799
 
        if null > 2:
800
 
            os.close(null)
801
 
    else:
802
 
        # No console logging
803
 
        logger.removeHandler(console)
804
 
        # Close all input and output, do double fork, etc.
805
 
        daemon()
806
 
    
807
 
    pidfilename = "/var/run/mandos/mandos.pid"
808
 
    pid = os.getpid()
 
149
    # Parse the time argument
809
150
    try:
810
 
        pidfile = open(pidfilename, "w")
811
 
        pidfile.write(str(pid) + "\n")
812
 
        pidfile.close()
813
 
        del pidfile
814
 
    except IOError, err:
815
 
        logger.error(u"Could not write %s file with PID %d",
816
 
                     pidfilename, os.getpid())
817
 
    
818
 
    def cleanup():
819
 
        "Cleanup function; run on exit"
820
 
        global group
821
 
        # From the Avahi example code
822
 
        if not group is None:
823
 
            group.Free()
824
 
            group = None
825
 
        # End of Avahi example code
826
 
        
827
 
        while clients:
828
 
            client = clients.pop()
829
 
            client.stop_hook = None
830
 
            client.stop()
831
 
    
832
 
    atexit.register(cleanup)
833
 
    
834
 
    if not debug:
835
 
        signal.signal(signal.SIGINT, signal.SIG_IGN)
836
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
837
 
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
838
 
    
839
 
    for client in clients:
840
 
        client.start()
841
 
    
842
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
843
 
                                 server_settings["port"]),
 
151
        suffix=options.timeout[-1]
 
152
        value=int(options.timeout[:-1])
 
153
        if suffix == "d":
 
154
            options.timeout = datetime.timedelta(value)
 
155
        elif suffix == "s":
 
156
            options.timeout = datetime.timedelta(0, value)
 
157
        elif suffix == "m":
 
158
            options.timeout = datetime.timedelta(0, 0, 0, 0, value)
 
159
        elif suffix == "h":
 
160
            options.timeout = datetime.timedelta(0, 0, 0, 0, 0, value)
 
161
        elif suffix == "w":
 
162
            options.timeout = datetime.timedelta(0, 0, 0, 0, 0, 0,
 
163
                                                 value)
 
164
        else:
 
165
            raise ValueError
 
166
    except (ValueError, IndexError):
 
167
        parser.error("option --timeout: Unparseable time")
 
168
    
 
169
    cert = gnutls.crypto.X509Certificate(open(options.cert).read())
 
170
    key = gnutls.crypto.X509PrivateKey(open(options.key).read())
 
171
    ca = gnutls.crypto.X509Certificate(open(options.ca).read())
 
172
    crl = gnutls.crypto.X509CRL(open(options.crl).read())
 
173
    cred = gnutls.connection.X509Credentials(cert, key, [ca], [crl])
 
174
    
 
175
    # Parse config file
 
176
    defaults = {}
 
177
    client_config_object = ConfigParser.SafeConfigParser(defaults)
 
178
    client_config_object.read("mandos-clients.conf")
 
179
    clients = [Client(name=section,
 
180
                      **(dict(client_config_object.items(section))))
 
181
               for section in client_config_object.sections()]
 
182
    
 
183
    udp_server = IPv6_UDPServer((in6addr_any, options.port),
 
184
                                udp_handler,
 
185
                                options=options)
 
186
    
 
187
    tcp_server = IPv6_TCPServer((in6addr_any, options.port),
844
188
                                tcp_handler,
845
 
                                settings=server_settings,
846
 
                                clients=clients)
847
 
    # Find out what port we got
848
 
    service.port = tcp_server.socket.getsockname()[1]
849
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
850
 
                u" scope_id %d" % tcp_server.socket.getsockname())
851
 
    
852
 
    #service.interface = tcp_server.socket.getsockname()[3]
853
 
    
854
 
    try:
855
 
        # From the Avahi example code
856
 
        server.connect_to_signal("StateChanged", server_state_changed)
857
 
        try:
858
 
            server_state_changed(server.GetState())
859
 
        except dbus.exceptions.DBusException, error:
860
 
            logger.critical(u"DBusException: %s", error)
861
 
            sys.exit(1)
862
 
        # End of Avahi example code
863
 
        
864
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
865
 
                             lambda *args, **kwargs:
866
 
                             tcp_server.handle_request\
867
 
                             (*args[2:], **kwargs) or True)
868
 
        
869
 
        logger.debug(u"Starting main loop")
870
 
        main_loop_started = True
871
 
        main_loop.run()
872
 
    except AvahiError, error:
873
 
        logger.critical(u"AvahiError: %s" + unicode(error))
874
 
        sys.exit(1)
875
 
    except KeyboardInterrupt:
876
 
        if debug:
877
 
            print
878
 
 
879
 
if __name__ == '__main__':
 
189
                                options=options,
 
190
                                clients=clients,
 
191
                                credentials=cred)
 
192
    
 
193
    while True:
 
194
        in_, out, err = select.select((udp_server,
 
195
                                       tcp_server), (), ())
 
196
        for server in in_:
 
197
            server.handle_request()
 
198
 
 
199
 
 
200
if __name__ == "__main__":
880
201
    main()
 
202