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  • Committer: Teddy Hogeborn
  • Date: 2008-01-18 22:04:19 UTC
  • Revision ID: teddy@fukt.bsnet.se-20080118220419-z95418owrporioo5
* Makefile (client_debug): New.
* client.cpp (CERT_ROOT): New.

(Tested)

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