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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
28
 
# <http://www.gnu.org/licenses/>.
29
 
30
 
# Contact the authors at <mandos@fukt.bsnet.se>.
31
 
32
 
 
33
 
from __future__ import division
34
2
 
35
3
import SocketServer
36
4
import socket
41
9
import gnutls.crypto
42
10
import gnutls.connection
43
11
import gnutls.errors
44
 
import gnutls.library.functions
45
 
import gnutls.library.constants
46
 
import gnutls.library.types
47
12
import ConfigParser
48
 
import sys
49
 
import re
50
 
import os
51
 
import signal
52
 
from sets import Set
53
 
import subprocess
54
 
import atexit
55
 
import stat
56
 
import logging
57
 
import logging.handlers
58
 
import pwd
59
 
 
60
 
import dbus
61
 
import gobject
62
 
import avahi
63
 
from dbus.mainloop.glib import DBusGMainLoop
64
 
import ctypes
65
 
 
66
 
version = "1.0"
67
 
 
68
 
logger = logging.Logger('mandos')
69
 
syslogger = logging.handlers.SysLogHandler\
70
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
71
 
             address = "/dev/log")
72
 
syslogger.setFormatter(logging.Formatter\
73
 
                        ('Mandos: %(levelname)s: %(message)s'))
74
 
logger.addHandler(syslogger)
75
 
 
76
 
console = logging.StreamHandler()
77
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
78
 
                                       ' %(message)s'))
79
 
logger.addHandler(console)
80
 
 
81
 
class AvahiError(Exception):
82
 
    def __init__(self, value):
83
 
        self.value = value
84
 
    def __str__(self):
85
 
        return repr(self.value)
86
 
 
87
 
class AvahiServiceError(AvahiError):
88
 
    pass
89
 
 
90
 
class AvahiGroupError(AvahiError):
91
 
    pass
92
 
 
93
 
 
94
 
class AvahiService(object):
95
 
    """An Avahi (Zeroconf) service.
96
 
    Attributes:
97
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
98
 
               Used to optionally bind to the specified interface.
99
 
    name: string; Example: 'Mandos'
100
 
    type: string; Example: '_mandos._tcp'.
101
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
102
 
    port: integer; what port to announce
103
 
    TXT: list of strings; TXT record for the service
104
 
    domain: string; Domain to publish on, default to .local if empty.
105
 
    host: string; Host to publish records for, default is localhost
106
 
    max_renames: integer; maximum number of renames
107
 
    rename_count: integer; counter so we only rename after collisions
108
 
                  a sensible number of times
109
 
    """
110
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
111
 
                 type = None, port = None, TXT = None, domain = "",
112
 
                 host = "", max_renames = 32768):
113
 
        self.interface = interface
114
 
        self.name = name
115
 
        self.type = type
116
 
        self.port = port
117
 
        if TXT is None:
118
 
            self.TXT = []
119
 
        else:
120
 
            self.TXT = TXT
121
 
        self.domain = domain
122
 
        self.host = host
123
 
        self.rename_count = 0
124
 
        self.max_renames = max_renames
125
 
    def rename(self):
126
 
        """Derived from the Avahi example code"""
127
 
        if self.rename_count >= self.max_renames:
128
 
            logger.critical(u"No suitable Zeroconf service name found"
129
 
                            u" after %i retries, exiting.",
130
 
                            rename_count)
131
 
            raise AvahiServiceError("Too many renames")
132
 
        self.name = server.GetAlternativeServiceName(self.name)
133
 
        logger.info(u"Changing Zeroconf service name to %r ...",
134
 
                    str(self.name))
135
 
        syslogger.setFormatter(logging.Formatter\
136
 
                               ('Mandos (%s): %%(levelname)s:'
137
 
                               ' %%(message)s' % self.name))
138
 
        self.remove()
139
 
        self.add()
140
 
        self.rename_count += 1
141
 
    def remove(self):
142
 
        """Derived from the Avahi example code"""
143
 
        if group is not None:
144
 
            group.Reset()
145
 
    def add(self):
146
 
        """Derived from the Avahi example code"""
147
 
        global group
148
 
        if group is None:
149
 
            group = dbus.Interface\
150
 
                    (bus.get_object(avahi.DBUS_NAME,
151
 
                                    server.EntryGroupNew()),
152
 
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
153
 
            group.connect_to_signal('StateChanged',
154
 
                                    entry_group_state_changed)
155
 
        logger.debug(u"Adding Zeroconf service '%s' of type '%s' ...",
156
 
                     service.name, service.type)
157
 
        group.AddService(
158
 
                self.interface,         # interface
159
 
                avahi.PROTO_INET6,      # protocol
160
 
                dbus.UInt32(0),         # flags
161
 
                self.name, self.type,
162
 
                self.domain, self.host,
163
 
                dbus.UInt16(self.port),
164
 
                avahi.string_array_to_txt_array(self.TXT))
165
 
        group.Commit()
166
 
 
167
 
# From the Avahi example code:
168
 
group = None                            # our entry group
169
 
# End of Avahi example code
170
 
 
171
13
 
172
14
class Client(object):
173
 
    """A representation of a client host served by this server.
174
 
    Attributes:
175
 
    name:      string; from the config file, used in log messages
176
 
    fingerprint: string (40 or 32 hexadecimal digits); used to
177
 
                 uniquely identify the client
178
 
    secret:    bytestring; sent verbatim (over TLS) to client
179
 
    host:      string; available for use by the checker command
180
 
    created:   datetime.datetime(); object creation, not client host
181
 
    last_checked_ok: datetime.datetime() or None if not yet checked OK
182
 
    timeout:   datetime.timedelta(); How long from last_checked_ok
183
 
                                     until this client is invalid
184
 
    interval:  datetime.timedelta(); How often to start a new checker
185
 
    stop_hook: If set, called by stop() as stop_hook(self)
186
 
    checker:   subprocess.Popen(); a running checker process used
187
 
                                   to see if the client lives.
188
 
                                   'None' if no process is running.
189
 
    checker_initiator_tag: a gobject event source tag, or None
190
 
    stop_initiator_tag:    - '' -
191
 
    checker_callback_tag:  - '' -
192
 
    checker_command: string; External command which is run to check if
193
 
                     client lives.  %() expansions are done at
194
 
                     runtime with vars(self) as dict, so that for
195
 
                     instance %(name)s can be used in the command.
196
 
    Private attibutes:
197
 
    _timeout: Real variable for 'timeout'
198
 
    _interval: Real variable for 'interval'
199
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
200
 
    _interval_milliseconds: - '' -
201
 
    """
202
 
    def _set_timeout(self, timeout):
203
 
        "Setter function for 'timeout' attribute"
204
 
        self._timeout = timeout
205
 
        self._timeout_milliseconds = ((self.timeout.days
206
 
                                       * 24 * 60 * 60 * 1000)
207
 
                                      + (self.timeout.seconds * 1000)
208
 
                                      + (self.timeout.microseconds
209
 
                                         // 1000))
210
 
    timeout = property(lambda self: self._timeout,
211
 
                       _set_timeout)
212
 
    del _set_timeout
213
 
    def _set_interval(self, interval):
214
 
        "Setter function for 'interval' attribute"
215
 
        self._interval = interval
216
 
        self._interval_milliseconds = ((self.interval.days
217
 
                                        * 24 * 60 * 60 * 1000)
218
 
                                       + (self.interval.seconds
219
 
                                          * 1000)
220
 
                                       + (self.interval.microseconds
221
 
                                          // 1000))
222
 
    interval = property(lambda self: self._interval,
223
 
                        _set_interval)
224
 
    del _set_interval
225
 
    def __init__(self, name = None, stop_hook=None, config={}):
226
 
        """Note: the 'checker' key in 'config' sets the
227
 
        'checker_command' attribute and *not* the 'checker'
228
 
        attribute."""
 
15
    def __init__(self, name=None, dn=None, password=None,
 
16
                 passfile=None, fqdn=None, timeout=None,
 
17
                 interval=-1):
229
18
        self.name = name
230
 
        logger.debug(u"Creating client %r", self.name)
231
 
        # Uppercase and remove spaces from fingerprint for later
232
 
        # comparison purposes with return value from the fingerprint()
233
 
        # function
234
 
        self.fingerprint = config["fingerprint"].upper()\
235
 
                           .replace(u" ", u"")
236
 
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
237
 
        if "secret" in config:
238
 
            self.secret = config["secret"].decode(u"base64")
239
 
        elif "secfile" in config:
240
 
            sf = open(config["secfile"])
241
 
            self.secret = sf.read()
242
 
            sf.close()
243
 
        else:
244
 
            raise TypeError(u"No secret or secfile for client %s"
245
 
                            % self.name)
246
 
        self.host = config.get("host", "")
247
 
        self.created = datetime.datetime.now()
248
 
        self.last_checked_ok = None
249
 
        self.timeout = string_to_delta(config["timeout"])
250
 
        self.interval = string_to_delta(config["interval"])
251
 
        self.stop_hook = stop_hook
252
 
        self.checker = None
253
 
        self.checker_initiator_tag = None
254
 
        self.stop_initiator_tag = None
255
 
        self.checker_callback_tag = None
256
 
        self.check_command = config["checker"]
257
 
    def start(self):
258
 
        """Start this client's checker and timeout hooks"""
259
 
        # Schedule a new checker to be started an 'interval' from now,
260
 
        # and every interval from then on.
261
 
        self.checker_initiator_tag = gobject.timeout_add\
262
 
                                     (self._interval_milliseconds,
263
 
                                      self.start_checker)
264
 
        # Also start a new checker *right now*.
265
 
        self.start_checker()
266
 
        # Schedule a stop() when 'timeout' has passed
267
 
        self.stop_initiator_tag = gobject.timeout_add\
268
 
                                  (self._timeout_milliseconds,
269
 
                                   self.stop)
270
 
    def stop(self):
271
 
        """Stop this client.
272
 
        The possibility that a client might be restarted is left open,
273
 
        but not currently used."""
274
 
        # If this client doesn't have a secret, it is already stopped.
275
 
        if hasattr(self, "secret") and self.secret:
276
 
            logger.info(u"Stopping client %s", self.name)
277
 
            self.secret = None
278
 
        else:
279
 
            return False
280
 
        if getattr(self, "stop_initiator_tag", False):
281
 
            gobject.source_remove(self.stop_initiator_tag)
282
 
            self.stop_initiator_tag = None
283
 
        if getattr(self, "checker_initiator_tag", False):
284
 
            gobject.source_remove(self.checker_initiator_tag)
285
 
            self.checker_initiator_tag = None
286
 
        self.stop_checker()
287
 
        if self.stop_hook:
288
 
            self.stop_hook(self)
289
 
        # Do not run this again if called by a gobject.timeout_add
290
 
        return False
291
 
    def __del__(self):
292
 
        self.stop_hook = None
293
 
        self.stop()
294
 
    def checker_callback(self, pid, condition):
295
 
        """The checker has completed, so take appropriate actions."""
296
 
        now = datetime.datetime.now()
297
 
        self.checker_callback_tag = None
298
 
        self.checker = None
299
 
        if os.WIFEXITED(condition) \
300
 
               and (os.WEXITSTATUS(condition) == 0):
301
 
            logger.info(u"Checker for %(name)s succeeded",
302
 
                        vars(self))
303
 
            self.last_checked_ok = now
304
 
            gobject.source_remove(self.stop_initiator_tag)
305
 
            self.stop_initiator_tag = gobject.timeout_add\
306
 
                                      (self._timeout_milliseconds,
307
 
                                       self.stop)
308
 
        elif not os.WIFEXITED(condition):
309
 
            logger.warning(u"Checker for %(name)s crashed?",
310
 
                           vars(self))
311
 
        else:
312
 
            logger.info(u"Checker for %(name)s failed",
313
 
                        vars(self))
314
 
    def start_checker(self):
315
 
        """Start a new checker subprocess if one is not running.
316
 
        If a checker already exists, leave it running and do
317
 
        nothing."""
318
 
        # The reason for not killing a running checker is that if we
319
 
        # did that, then if a checker (for some reason) started
320
 
        # running slowly and taking more than 'interval' time, the
321
 
        # client would inevitably timeout, since no checker would get
322
 
        # a chance to run to completion.  If we instead leave running
323
 
        # checkers alone, the checker would have to take more time
324
 
        # than 'timeout' for the client to be declared invalid, which
325
 
        # is as it should be.
326
 
        if self.checker is None:
327
 
            try:
328
 
                # In case check_command has exactly one % operator
329
 
                command = self.check_command % self.host
330
 
            except TypeError:
331
 
                # Escape attributes for the shell
332
 
                escaped_attrs = dict((key, re.escape(str(val)))
333
 
                                     for key, val in
334
 
                                     vars(self).iteritems())
335
 
                try:
336
 
                    command = self.check_command % escaped_attrs
337
 
                except TypeError, error:
338
 
                    logger.error(u'Could not format string "%s":'
339
 
                                 u' %s', self.check_command, error)
340
 
                    return True # Try again later
341
 
            try:
342
 
                logger.info(u"Starting checker %r for %s",
343
 
                            command, self.name)
344
 
                # We don't need to redirect stdout and stderr, since
345
 
                # in normal mode, that is already done by daemon(),
346
 
                # and in debug mode we don't want to.  (Stdin is
347
 
                # always replaced by /dev/null.)
348
 
                self.checker = subprocess.Popen(command,
349
 
                                                close_fds=True,
350
 
                                                shell=True, cwd="/")
351
 
                self.checker_callback_tag = gobject.child_watch_add\
352
 
                                            (self.checker.pid,
353
 
                                             self.checker_callback)
354
 
            except OSError, error:
355
 
                logger.error(u"Failed to start subprocess: %s",
356
 
                             error)
357
 
        # Re-run this periodically if run by gobject.timeout_add
358
 
        return True
359
 
    def stop_checker(self):
360
 
        """Force the checker process, if any, to stop."""
361
 
        if self.checker_callback_tag:
362
 
            gobject.source_remove(self.checker_callback_tag)
363
 
            self.checker_callback_tag = None
364
 
        if getattr(self, "checker", None) is None:
365
 
            return
366
 
        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
367
43
        try:
368
 
            os.kill(self.checker.pid, signal.SIGTERM)
369
 
            #os.sleep(0.5)
370
 
            #if self.checker.poll() is None:
371
 
            #    os.kill(self.checker.pid, signal.SIGKILL)
372
 
        except OSError, error:
373
 
            if error.errno != errno.ESRCH: # No such process
374
 
                raise
375
 
        self.checker = None
376
 
    def still_valid(self):
377
 
        """Has the timeout not yet passed for this client?"""
378
 
        now = datetime.datetime.now()
379
 
        if self.last_checked_ok is None:
380
 
            return now < (self.created + self.timeout)
381
 
        else:
382
 
            return now < (self.last_checked_ok + self.timeout)
383
 
 
384
 
 
385
 
def peer_certificate(session):
386
 
    "Return the peer's OpenPGP certificate as a bytestring"
387
 
    # If not an OpenPGP certificate...
388
 
    if gnutls.library.functions.gnutls_certificate_type_get\
389
 
            (session._c_object) \
390
 
           != gnutls.library.constants.GNUTLS_CRT_OPENPGP:
391
 
        # ...do the normal thing
392
 
        return session.peer_certificate
393
 
    list_size = ctypes.c_uint()
394
 
    cert_list = gnutls.library.functions.gnutls_certificate_get_peers\
395
 
        (session._c_object, ctypes.byref(list_size))
396
 
    if list_size.value == 0:
397
 
        return None
398
 
    cert = cert_list[0]
399
 
    return ctypes.string_at(cert.data, cert.size)
400
 
 
401
 
 
402
 
def fingerprint(openpgp):
403
 
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
404
 
    # New GnuTLS "datum" with the OpenPGP public key
405
 
    datum = gnutls.library.types.gnutls_datum_t\
406
 
        (ctypes.cast(ctypes.c_char_p(openpgp),
407
 
                     ctypes.POINTER(ctypes.c_ubyte)),
408
 
         ctypes.c_uint(len(openpgp)))
409
 
    # New empty GnuTLS certificate
410
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
411
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
412
 
        (ctypes.byref(crt))
413
 
    # Import the OpenPGP public key into the certificate
414
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
415
 
                    (crt, ctypes.byref(datum),
416
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
417
 
    # Verify the self signature in the key
418
 
    crtverify = ctypes.c_uint();
419
 
    gnutls.library.functions.gnutls_openpgp_crt_verify_self\
420
 
        (crt, 0, ctypes.byref(crtverify))
421
 
    if crtverify.value != 0:
422
 
        gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
423
 
        raise gnutls.errors.CertificateSecurityError("Verify failed")
424
 
    # New buffer for the fingerprint
425
 
    buffer = ctypes.create_string_buffer(20)
426
 
    buffer_length = ctypes.c_size_t()
427
 
    # Get the fingerprint from the certificate into the buffer
428
 
    gnutls.library.functions.gnutls_openpgp_crt_get_fingerprint\
429
 
        (crt, ctypes.byref(buffer), ctypes.byref(buffer_length))
430
 
    # Deinit the certificate
431
 
    gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
432
 
    # Convert the buffer to a Python bytestring
433
 
    fpr = ctypes.string_at(buffer, buffer_length.value)
434
 
    # Convert the bytestring to hexadecimal notation
435
 
    hex_fpr = u''.join(u"%02X" % ord(char) for char in fpr)
436
 
    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"
437
83
 
438
84
 
439
85
class tcp_handler(SocketServer.BaseRequestHandler, object):
440
 
    """A TCP request handler class.
441
 
    Instantiated by IPv6_TCPServer for each request to handle it.
442
 
    Note: This will run in its own forked process."""
443
 
    
444
86
    def handle(self):
445
 
        logger.info(u"TCP connection from: %s",
446
 
                     unicode(self.client_address))
447
 
        session = gnutls.connection.ClientSession\
448
 
                  (self.request, gnutls.connection.X509Credentials())
449
 
        
450
 
        line = self.request.makefile().readline()
451
 
        logger.debug(u"Protocol version: %r", line)
452
 
        try:
453
 
            if int(line.strip().split()[0]) > 1:
454
 
                raise RuntimeError
455
 
        except (ValueError, IndexError, RuntimeError), error:
456
 
            logger.error(u"Unknown protocol version: %s", error)
457
 
            return
458
 
        
459
 
        # Note: gnutls.connection.X509Credentials is really a generic
460
 
        # GnuTLS certificate credentials object so long as no X.509
461
 
        # keys are added to it.  Therefore, we can use it here despite
462
 
        # using OpenPGP certificates.
463
 
        
464
 
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
465
 
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
466
 
        #                "+DHE-DSS"))
467
 
        priority = "NORMAL"             # Fallback default, since this
468
 
                                        # MUST be set.
469
 
        if self.server.settings["priority"]:
470
 
            priority = self.server.settings["priority"]
471
 
        gnutls.library.functions.gnutls_priority_set_direct\
472
 
            (session._c_object, priority, None);
473
 
        
474
 
        try:
475
 
            session.handshake()
476
 
        except gnutls.errors.GNUTLSError, error:
477
 
            logger.warning(u"Handshake failed: %s", error)
478
 
            # Do not run session.bye() here: the session is not
479
 
            # established.  Just abandon the request.
480
 
            return
481
 
        try:
482
 
            fpr = fingerprint(peer_certificate(session))
483
 
        except (TypeError, gnutls.errors.GNUTLSError), error:
484
 
            logger.warning(u"Bad certificate: %s", error)
485
 
            session.bye()
486
 
            return
487
 
        logger.debug(u"Fingerprint: %s", fpr)
488
 
        client = None
489
 
        for c in self.server.clients:
490
 
            if c.fingerprint == fpr:
491
 
                client = c
492
 
                break
493
 
        if not client:
494
 
            logger.warning(u"Client not found for fingerprint: %s",
495
 
                           fpr)
496
 
            session.bye()
497
 
            return
498
 
        # Have to check if client.still_valid(), since it is possible
499
 
        # that the client timed out while establishing the GnuTLS
500
 
        # session.
501
 
        if not client.still_valid():
502
 
            logger.warning(u"Client %(name)s is invalid",
503
 
                           vars(client))
504
 
            session.bye()
505
 
            return
506
 
        sent_size = 0
507
 
        while sent_size < len(client.secret):
508
 
            sent = session.send(client.secret[sent_size:])
509
 
            logger.debug(u"Sent: %d, remaining: %d",
510
 
                         sent, len(client.secret)
511
 
                         - (sent_size + sent))
512
 
            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
513
109
        session.bye()
514
110
 
515
 
 
516
111
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
517
 
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
518
 
    Attributes:
519
 
        settings:       Server settings
520
 
        clients:        Set() of Client objects
521
 
        enabled:        Boolean; whether this server is activated yet
522
 
    """
 
112
    __init__ = init_with_options
523
113
    address_family = socket.AF_INET6
524
 
    def __init__(self, *args, **kwargs):
525
 
        if "settings" in kwargs:
526
 
            self.settings = kwargs["settings"]
527
 
            del kwargs["settings"]
528
 
        if "clients" in kwargs:
529
 
            self.clients = kwargs["clients"]
530
 
            del kwargs["clients"]
531
 
        self.enabled = False
532
 
        return super(type(self), self).__init__(*args, **kwargs)
533
 
    def server_bind(self):
534
 
        """This overrides the normal server_bind() function
535
 
        to bind to an interface if one was specified, and also NOT to
536
 
        bind to an address or port if they were not specified."""
537
 
        if self.settings["interface"]:
538
 
            # 25 is from /usr/include/asm-i486/socket.h
539
 
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
540
 
            try:
541
 
                self.socket.setsockopt(socket.SOL_SOCKET,
542
 
                                       SO_BINDTODEVICE,
543
 
                                       self.settings["interface"])
544
 
            except socket.error, error:
545
 
                if error[0] == errno.EPERM:
546
 
                    logger.error(u"No permission to"
547
 
                                 u" bind to interface %s",
548
 
                                 self.settings["interface"])
549
 
                else:
550
 
                    raise error
551
 
        # Only bind(2) the socket if we really need to.
552
 
        if self.server_address[0] or self.server_address[1]:
553
 
            if not self.server_address[0]:
554
 
                in6addr_any = "::"
555
 
                self.server_address = (in6addr_any,
556
 
                                       self.server_address[1])
557
 
            elif not self.server_address[1]:
558
 
                self.server_address = (self.server_address[0],
559
 
                                       0)
560
 
#                 if self.settings["interface"]:
561
 
#                     self.server_address = (self.server_address[0],
562
 
#                                            0, # port
563
 
#                                            0, # flowinfo
564
 
#                                            if_nametoindex
565
 
#                                            (self.settings
566
 
#                                             ["interface"]))
567
 
            return super(type(self), self).server_bind()
568
 
    def server_activate(self):
569
 
        if self.enabled:
570
 
            return super(type(self), self).server_activate()
571
 
    def enable(self):
572
 
        self.enabled = True
573
 
 
574
 
 
575
 
def string_to_delta(interval):
576
 
    """Parse a string and return a datetime.timedelta
577
 
 
578
 
    >>> string_to_delta('7d')
579
 
    datetime.timedelta(7)
580
 
    >>> string_to_delta('60s')
581
 
    datetime.timedelta(0, 60)
582
 
    >>> string_to_delta('60m')
583
 
    datetime.timedelta(0, 3600)
584
 
    >>> string_to_delta('24h')
585
 
    datetime.timedelta(1)
586
 
    >>> string_to_delta(u'1w')
587
 
    datetime.timedelta(7)
588
 
    >>> string_to_delta('5m 30s')
589
 
    datetime.timedelta(0, 330)
590
 
    """
591
 
    timevalue = datetime.timedelta(0)
592
 
    for s in interval.split():
593
 
        try:
594
 
            suffix=unicode(s[-1])
595
 
            value=int(s[:-1])
596
 
            if suffix == u"d":
597
 
                delta = datetime.timedelta(value)
598
 
            elif suffix == u"s":
599
 
                delta = datetime.timedelta(0, value)
600
 
            elif suffix == u"m":
601
 
                delta = datetime.timedelta(0, 0, 0, 0, value)
602
 
            elif suffix == u"h":
603
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, value)
604
 
            elif suffix == u"w":
605
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
606
 
            else:
607
 
                raise ValueError
608
 
        except (ValueError, IndexError):
609
 
            raise ValueError
610
 
        timevalue += delta
611
 
    return timevalue
612
 
 
613
 
 
614
 
def server_state_changed(state):
615
 
    """Derived from the Avahi example code"""
616
 
    if state == avahi.SERVER_COLLISION:
617
 
        logger.error(u"Zeroconf server name collision")
618
 
        service.remove()
619
 
    elif state == avahi.SERVER_RUNNING:
620
 
        service.add()
621
 
 
622
 
 
623
 
def entry_group_state_changed(state, error):
624
 
    """Derived from the Avahi example code"""
625
 
    logger.debug(u"Avahi state change: %i", state)
626
 
    
627
 
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
628
 
        logger.debug(u"Zeroconf service established.")
629
 
    elif state == avahi.ENTRY_GROUP_COLLISION:
630
 
        logger.warning(u"Zeroconf service name collision.")
631
 
        service.rename()
632
 
    elif state == avahi.ENTRY_GROUP_FAILURE:
633
 
        logger.critical(u"Avahi: Error in group state changed %s",
634
 
                        unicode(error))
635
 
        raise AvahiGroupError("State changed: %s", str(error))
636
 
 
637
 
def if_nametoindex(interface):
638
 
    """Call the C function if_nametoindex(), or equivalent"""
639
 
    global if_nametoindex
640
 
    try:
641
 
        if "ctypes.util" not in sys.modules:
642
 
            import ctypes.util
643
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
644
 
            (ctypes.util.find_library("c")).if_nametoindex
645
 
    except (OSError, AttributeError):
646
 
        if "struct" not in sys.modules:
647
 
            import struct
648
 
        if "fcntl" not in sys.modules:
649
 
            import fcntl
650
 
        def if_nametoindex(interface):
651
 
            "Get an interface index the hard way, i.e. using fcntl()"
652
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
653
 
            s = socket.socket()
654
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
655
 
                                struct.pack("16s16x", interface))
656
 
            s.close()
657
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
658
 
            return interface_index
659
 
    return if_nametoindex(interface)
660
 
 
661
 
 
662
 
def daemon(nochdir = False, noclose = False):
663
 
    """See daemon(3).  Standard BSD Unix function.
664
 
    This should really exist as os.daemon, but it doesn't (yet)."""
665
 
    if os.fork():
666
 
        sys.exit()
667
 
    os.setsid()
668
 
    if not nochdir:
669
 
        os.chdir("/")
670
 
    if os.fork():
671
 
        sys.exit()
672
 
    if not noclose:
673
 
        # Close all standard open file descriptors
674
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
675
 
        if not stat.S_ISCHR(os.fstat(null).st_mode):
676
 
            raise OSError(errno.ENODEV,
677
 
                          "/dev/null not a character device")
678
 
        os.dup2(null, sys.stdin.fileno())
679
 
        os.dup2(null, sys.stdout.fileno())
680
 
        os.dup2(null, sys.stderr.fileno())
681
 
        if null > 2:
682
 
            os.close(null)
683
 
 
 
114
    allow_reuse_address = True
 
115
    request_queue_size = 1024
 
116
    server_bind = server_bind
 
117
 
 
118
 
 
119
in6addr_any = "::"
 
120
 
 
121
cred = None
684
122
 
685
123
def main():
686
 
    global main_loop_started
687
 
    main_loop_started = False
688
 
    
689
 
    parser = OptionParser(version = "%%prog %s" % version)
 
124
    parser = OptionParser()
690
125
    parser.add_option("-i", "--interface", type="string",
691
 
                      metavar="IF", help="Bind to interface IF")
692
 
    parser.add_option("-a", "--address", type="string",
693
 
                      help="Address to listen for requests on")
694
 
    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,
695
141
                      help="Port number to receive requests on")
696
 
    parser.add_option("--check", action="store_true", default=False,
697
 
                      help="Run self-test")
698
 
    parser.add_option("--debug", action="store_true",
699
 
                      help="Debug mode; run in foreground and log to"
700
 
                      " terminal")
701
 
    parser.add_option("--priority", type="string", help="GnuTLS"
702
 
                      " priority string (see GnuTLS documentation)")
703
 
    parser.add_option("--servicename", type="string", metavar="NAME",
704
 
                      help="Zeroconf service name")
705
 
    parser.add_option("--configdir", type="string",
706
 
                      default="/etc/mandos", metavar="DIR",
707
 
                      help="Directory to search for configuration"
708
 
                      " 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")
709
147
    (options, args) = parser.parse_args()
710
148
    
711
 
    if options.check:
712
 
        import doctest
713
 
        doctest.testmod()
714
 
        sys.exit()
715
 
    
716
 
    # Default values for config file for server-global settings
717
 
    server_defaults = { "interface": "",
718
 
                        "address": "",
719
 
                        "port": "",
720
 
                        "debug": "False",
721
 
                        "priority":
722
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
723
 
                        "servicename": "Mandos",
724
 
                        }
725
 
    
726
 
    # Parse config file for server-global settings
727
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
728
 
    del server_defaults
729
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
730
 
    # Convert the SafeConfigParser object to a dict
731
 
    server_settings = server_config.defaults()
732
 
    # Use getboolean on the boolean config option
733
 
    server_settings["debug"] = server_config.getboolean\
734
 
                               ("DEFAULT", "debug")
735
 
    del server_config
736
 
    
737
 
    # Override the settings from the config file with command line
738
 
    # options, if set.
739
 
    for option in ("interface", "address", "port", "debug",
740
 
                   "priority", "servicename", "configdir"):
741
 
        value = getattr(options, option)
742
 
        if value is not None:
743
 
            server_settings[option] = value
744
 
    del options
745
 
    # Now we have our good server settings in "server_settings"
746
 
    
747
 
    debug = server_settings["debug"]
748
 
    
749
 
    if not debug:
750
 
        syslogger.setLevel(logging.WARNING)
751
 
        console.setLevel(logging.WARNING)
752
 
    
753
 
    if server_settings["servicename"] != "Mandos":
754
 
        syslogger.setFormatter(logging.Formatter\
755
 
                               ('Mandos (%s): %%(levelname)s:'
756
 
                                ' %%(message)s'
757
 
                                % server_settings["servicename"]))
758
 
    
759
 
    # Parse config file with clients
760
 
    client_defaults = { "timeout": "1h",
761
 
                        "interval": "5m",
762
 
                        "checker": "fping -q -- %(host)s",
763
 
                        "host": "",
764
 
                        }
765
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
766
 
    client_config.read(os.path.join(server_settings["configdir"],
767
 
                                    "clients.conf"))
768
 
    
769
 
    clients = Set()
770
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
771
 
                                 server_settings["port"]),
 
149
    # Parse the time argument
 
150
    try:
 
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),
772
188
                                tcp_handler,
773
 
                                settings=server_settings,
774
 
                                clients=clients)
775
 
    pidfilename = "/var/run/mandos.pid"
776
 
    try:
777
 
        pidfile = open(pidfilename, "w")
778
 
    except IOError, error:
779
 
        logger.error("Could not open file %r", pidfilename)
780
 
    
781
 
    uid = 65534
782
 
    gid = 65534
783
 
    try:
784
 
        uid = pwd.getpwnam("mandos").pw_uid
785
 
    except KeyError:
786
 
        try:
787
 
            uid = pwd.getpwnam("nobody").pw_uid
788
 
        except KeyError:
789
 
            pass
790
 
    try:
791
 
        gid = pwd.getpwnam("mandos").pw_gid
792
 
    except KeyError:
793
 
        try:
794
 
            gid = pwd.getpwnam("nogroup").pw_gid
795
 
        except KeyError:
796
 
            pass
797
 
    try:
798
 
        os.setuid(uid)
799
 
        os.setgid(gid)
800
 
    except OSError, error:
801
 
        if error[0] != errno.EPERM:
802
 
            raise error
803
 
    
804
 
    global service
805
 
    service = AvahiService(name = server_settings["servicename"],
806
 
                           type = "_mandos._tcp", );
807
 
    if server_settings["interface"]:
808
 
        service.interface = if_nametoindex\
809
 
                            (server_settings["interface"])
810
 
    
811
 
    global main_loop
812
 
    global bus
813
 
    global server
814
 
    # From the Avahi example code
815
 
    DBusGMainLoop(set_as_default=True )
816
 
    main_loop = gobject.MainLoop()
817
 
    bus = dbus.SystemBus()
818
 
    server = dbus.Interface(bus.get_object(avahi.DBUS_NAME,
819
 
                                           avahi.DBUS_PATH_SERVER),
820
 
                            avahi.DBUS_INTERFACE_SERVER)
821
 
    # End of Avahi example code
822
 
    
823
 
    def remove_from_clients(client):
824
 
        clients.remove(client)
825
 
        if not clients:
826
 
            logger.critical(u"No clients left, exiting")
827
 
            sys.exit()
828
 
    
829
 
    clients.update(Set(Client(name = section,
830
 
                              stop_hook = remove_from_clients,
831
 
                              config
832
 
                              = dict(client_config.items(section)))
833
 
                       for section in client_config.sections()))
834
 
    if not clients:
835
 
        logger.critical(u"No clients defined")
836
 
        sys.exit(1)
837
 
    
838
 
    if debug:
839
 
        # Redirect stdin so all checkers get /dev/null
840
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
841
 
        os.dup2(null, sys.stdin.fileno())
842
 
        if null > 2:
843
 
            os.close(null)
844
 
    else:
845
 
        # No console logging
846
 
        logger.removeHandler(console)
847
 
        # Close all input and output, do double fork, etc.
848
 
        daemon()
849
 
    
850
 
    try:
851
 
        pid = os.getpid()
852
 
        pidfile.write(str(pid) + "\n")
853
 
        pidfile.close()
854
 
        del pidfile
855
 
    except IOError, err:
856
 
        logger.error(u"Could not write to file %r with PID %d",
857
 
                     pidfilename, pid)
858
 
    except NameError:
859
 
        # "pidfile" was never created
860
 
        pass
861
 
    del pidfilename
862
 
    
863
 
    def cleanup():
864
 
        "Cleanup function; run on exit"
865
 
        global group
866
 
        # From the Avahi example code
867
 
        if not group is None:
868
 
            group.Free()
869
 
            group = None
870
 
        # End of Avahi example code
871
 
        
872
 
        while clients:
873
 
            client = clients.pop()
874
 
            client.stop_hook = None
875
 
            client.stop()
876
 
    
877
 
    atexit.register(cleanup)
878
 
    
879
 
    if not debug:
880
 
        signal.signal(signal.SIGINT, signal.SIG_IGN)
881
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
882
 
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
883
 
    
884
 
    for client in clients:
885
 
        client.start()
886
 
    
887
 
    tcp_server.enable()
888
 
    tcp_server.server_activate()
889
 
    
890
 
    # Find out what port we got
891
 
    service.port = tcp_server.socket.getsockname()[1]
892
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
893
 
                u" scope_id %d" % tcp_server.socket.getsockname())
894
 
    
895
 
    #service.interface = tcp_server.socket.getsockname()[3]
896
 
    
897
 
    try:
898
 
        # From the Avahi example code
899
 
        server.connect_to_signal("StateChanged", server_state_changed)
900
 
        try:
901
 
            server_state_changed(server.GetState())
902
 
        except dbus.exceptions.DBusException, error:
903
 
            logger.critical(u"DBusException: %s", error)
904
 
            sys.exit(1)
905
 
        # End of Avahi example code
906
 
        
907
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
908
 
                             lambda *args, **kwargs:
909
 
                             tcp_server.handle_request\
910
 
                             (*args[2:], **kwargs) or True)
911
 
        
912
 
        logger.debug(u"Starting main loop")
913
 
        main_loop_started = True
914
 
        main_loop.run()
915
 
    except AvahiError, error:
916
 
        logger.critical(u"AvahiError: %s" + unicode(error))
917
 
        sys.exit(1)
918
 
    except KeyboardInterrupt:
919
 
        if debug:
920
 
            print
921
 
 
922
 
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__":
923
201
    main()
 
202