/mandos/release

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  • Committer: Björn Påhlsson
  • Date: 2008-07-20 02:52:20 UTC
  • Revision ID: belorn@braxen-20080720025220-r5u0388uy9iu23h6
Added following support:
Pluginbased client handler
rewritten Mandos client
       Avahi instead of udp server discovery
       openpgp encrypted key support
Passprompt stand alone application for direct console input
Added logging for Mandos server

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server.py
1
1
#!/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
2
 
32
3
from __future__ import division
33
4
 
50
21
import signal
51
22
from sets import Set
52
23
import subprocess
53
 
import atexit
54
 
import stat
55
 
import logging
56
 
import logging.handlers
57
24
 
58
25
import dbus
59
26
import gobject
61
28
from dbus.mainloop.glib import DBusGMainLoop
62
29
import ctypes
63
30
 
64
 
version = "1.0"
 
31
import logging
 
32
import logging.handlers
 
33
 
 
34
# logghandler.setFormatter(logging.Formatter('%(levelname)s %(message)s')
65
35
 
66
36
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
 
37
logger.addHandler(logging.handlers.SysLogHandler(facility = logging.handlers.SysLogHandler.LOG_DAEMON))
 
38
 
 
39
# This variable is used to optionally bind to a specified interface.
 
40
# It is a global variable to fit in with the other variables from the
 
41
# Avahi server example code.
 
42
serviceInterface = avahi.IF_UNSPEC
 
43
# From the Avahi server example code:
 
44
serviceName = "Mandos"
 
45
serviceType = "_mandos._tcp" # http://www.dns-sd.org/ServiceTypes.html
 
46
servicePort = None                      # Not known at startup
 
47
serviceTXT = []                         # TXT record for the service
 
48
domain = ""                  # Domain to publish on, default to .local
 
49
host = ""          # Host to publish records for, default to localhost
 
50
group = None #our entry group
 
51
rename_count = 12       # Counter so we only rename after collisions a
 
52
                        # sensible number of times
164
53
# End of Avahi example code
165
54
 
166
55
 
171
60
    fingerprint: string (40 or 32 hexadecimal digits); used to
172
61
                 uniquely identify the client
173
62
    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
 
63
    fqdn:      string (FQDN); available for use by the checker command
 
64
    created:   datetime.datetime()
 
65
    last_seen: datetime.datetime() or None if not yet seen
 
66
    timeout:   datetime.timedelta(); How long from last_seen until
 
67
                                     this client is invalid
179
68
    interval:  datetime.timedelta(); How often to start a new checker
180
69
    stop_hook: If set, called by stop() as stop_hook(self)
181
70
    checker:   subprocess.Popen(); a running checker process used
182
71
                                   to see if the client lives.
183
 
                                   'None' if no process is running.
 
72
                                   Is None if no process is running.
184
73
    checker_initiator_tag: a gobject event source tag, or None
185
74
    stop_initiator_tag:    - '' -
186
75
    checker_callback_tag:  - '' -
187
76
    checker_command: string; External command which is run to check if
188
 
                     client lives.  %() expansions are done at
 
77
                     client lives.  %()s expansions are done at
189
78
                     runtime with vars(self) as dict, so that for
190
79
                     instance %(name)s can be used in the command.
191
80
    Private attibutes:
192
81
    _timeout: Real variable for 'timeout'
193
82
    _interval: Real variable for 'interval'
194
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
 
83
    _timeout_milliseconds: Used by gobject.timeout_add()
195
84
    _interval_milliseconds: - '' -
196
85
    """
197
86
    def _set_timeout(self, timeout):
217
106
    interval = property(lambda self: self._interval,
218
107
                        _set_interval)
219
108
    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."""
 
109
    def __init__(self, name=None, options=None, stop_hook=None,
 
110
                 fingerprint=None, secret=None, secfile=None, fqdn=None,
 
111
                 timeout=None, interval=-1, checker=None):
224
112
        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"])
 
113
        # Uppercase and remove spaces from fingerprint
 
114
        # for later comparison purposes with return value of
 
115
        # the fingerprint() function
 
116
        self.fingerprint = fingerprint.upper().replace(u" ", u"")
 
117
        if secret:
 
118
            self.secret = secret.decode(u"base64")
 
119
        elif secfile:
 
120
            sf = open(secfile)
236
121
            self.secret = sf.read()
237
122
            sf.close()
238
123
        else:
239
 
            raise TypeError(u"No secret or secfile for client %s"
240
 
                            % self.name)
241
 
        self.host = config.get("host", "")
 
124
            raise RuntimeError(u"No secret or secfile for client %s"
 
125
                               % self.name)
 
126
        self.fqdn = fqdn                # string
242
127
        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"])
 
128
        self.last_seen = None
 
129
        if timeout is None:
 
130
            timeout = options.timeout
 
131
        self.timeout = timeout
 
132
        if interval == -1:
 
133
            interval = options.interval
 
134
        else:
 
135
            interval = string_to_delta(interval)
 
136
        self.interval = interval
246
137
        self.stop_hook = stop_hook
247
138
        self.checker = None
248
139
        self.checker_initiator_tag = None
249
140
        self.stop_initiator_tag = None
250
141
        self.checker_callback_tag = None
251
 
        self.check_command = config["checker"]
 
142
        self.check_command = checker
252
143
    def start(self):
253
 
        """Start this client's checker and timeout hooks"""
 
144
        """Start this clients checker and timeout hooks"""
254
145
        # Schedule a new checker to be started an 'interval' from now,
255
146
        # and every interval from then on.
256
147
        self.checker_initiator_tag = gobject.timeout_add\
264
155
                                   self.stop)
265
156
    def stop(self):
266
157
        """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):
 
158
        The possibility that this client might be restarted is left
 
159
        open, but not currently used."""
 
160
        logger.debug(u"Stopping client %s", self.name)
 
161
        self.secret = None
 
162
        if self.stop_initiator_tag:
276
163
            gobject.source_remove(self.stop_initiator_tag)
277
164
            self.stop_initiator_tag = None
278
 
        if getattr(self, "checker_initiator_tag", False):
 
165
        if self.checker_initiator_tag:
279
166
            gobject.source_remove(self.checker_initiator_tag)
280
167
            self.checker_initiator_tag = None
281
168
        self.stop_checker()
284
171
        # Do not run this again if called by a gobject.timeout_add
285
172
        return False
286
173
    def __del__(self):
287
 
        self.stop_hook = None
288
 
        self.stop()
 
174
        # Some code duplication here and in stop()
 
175
        if hasattr(self, "stop_initiator_tag") \
 
176
               and self.stop_initiator_tag:
 
177
            gobject.source_remove(self.stop_initiator_tag)
 
178
            self.stop_initiator_tag = None
 
179
        if hasattr(self, "checker_initiator_tag") \
 
180
               and self.checker_initiator_tag:
 
181
            gobject.source_remove(self.checker_initiator_tag)
 
182
            self.checker_initiator_tag = None
 
183
        self.stop_checker()
289
184
    def checker_callback(self, pid, condition):
290
185
        """The checker has completed, so take appropriate actions."""
291
186
        now = datetime.datetime.now()
292
 
        self.checker_callback_tag = None
293
 
        self.checker = None
294
187
        if os.WIFEXITED(condition) \
295
188
               and (os.WEXITSTATUS(condition) == 0):
296
 
            logger.info(u"Checker for %(name)s succeeded",
297
 
                        vars(self))
298
 
            self.last_checked_ok = now
 
189
            logger.debug(u"Checker for %(name)s succeeded",
 
190
                         vars(self))
 
191
            self.last_seen = now
299
192
            gobject.source_remove(self.stop_initiator_tag)
300
193
            self.stop_initiator_tag = gobject.timeout_add\
301
194
                                      (self._timeout_milliseconds,
302
195
                                       self.stop)
303
 
        elif not os.WIFEXITED(condition):
 
196
        if not os.WIFEXITED(condition):
304
197
            logger.warning(u"Checker for %(name)s crashed?",
305
198
                           vars(self))
306
199
        else:
307
 
            logger.info(u"Checker for %(name)s failed",
308
 
                        vars(self))
 
200
            logger.debug(u"Checker for %(name)s failed",
 
201
                         vars(self))
 
202
            self.checker = None
 
203
        self.checker_callback_tag = None
309
204
    def start_checker(self):
310
205
        """Start a new checker subprocess if one is not running.
311
206
        If a checker already exists, leave it running and do
312
207
        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
208
        if self.checker is None:
 
209
            logger.debug(u"Starting checker for %s",
 
210
                         self.name)
322
211
            try:
323
 
                # In case check_command has exactly one % operator
324
 
                command = self.check_command % self.host
 
212
                command = self.check_command % self.fqdn
325
213
            except TypeError:
326
 
                # Escape attributes for the shell
327
214
                escaped_attrs = dict((key, re.escape(str(val)))
328
215
                                     for key, val in
329
216
                                     vars(self).iteritems())
330
217
                try:
331
218
                    command = self.check_command % escaped_attrs
332
219
                except TypeError, error:
333
 
                    logger.error(u'Could not format string "%s":'
334
 
                                 u' %s', self.check_command, error)
 
220
                    logger.critical(u'Could not format string "%s": %s',
 
221
                                    self.check_command, error)
335
222
                    return True # Try again later
336
223
            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)
 
224
                self.checker = subprocess.\
 
225
                               Popen(command,
 
226
                                     stdout=subprocess.PIPE,
 
227
                                     close_fds=True, shell=True,
 
228
                                     cwd="/")
 
229
                self.checker_callback_tag = gobject.\
 
230
                                            child_watch_add(self.checker.pid,
 
231
                                                            self.\
 
232
                                                            checker_callback)
345
233
            except subprocess.OSError, error:
346
234
                logger.error(u"Failed to start subprocess: %s",
347
235
                             error)
349
237
        return True
350
238
    def stop_checker(self):
351
239
        """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:
 
240
        if not hasattr(self, "checker") or self.checker is None:
356
241
            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
 
242
        gobject.source_remove(self.checker_callback_tag)
 
243
        self.checker_callback_tag = None
 
244
        os.kill(self.checker.pid, signal.SIGTERM)
 
245
        if self.checker.poll() is None:
 
246
            os.kill(self.checker.pid, signal.SIGKILL)
366
247
        self.checker = None
367
 
    def still_valid(self):
 
248
    def still_valid(self, now=None):
368
249
        """Has the timeout not yet passed for this client?"""
369
 
        now = datetime.datetime.now()
370
 
        if self.last_checked_ok is None:
 
250
        if now is None:
 
251
            now = datetime.datetime.now()
 
252
        if self.last_seen is None:
371
253
            return now < (self.created + self.timeout)
372
254
        else:
373
 
            return now < (self.last_checked_ok + self.timeout)
 
255
            return now < (self.last_seen + self.timeout)
374
256
 
375
257
 
376
258
def peer_certificate(session):
377
 
    "Return the peer's OpenPGP certificate as a bytestring"
378
259
    # If not an OpenPGP certificate...
379
260
    if gnutls.library.functions.gnutls_certificate_type_get\
380
261
            (session._c_object) \
391
272
 
392
273
 
393
274
def fingerprint(openpgp):
394
 
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
 
275
    # New empty GnuTLS certificate
 
276
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
277
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
278
        (ctypes.byref(crt))
395
279
    # New GnuTLS "datum" with the OpenPGP public key
396
280
    datum = gnutls.library.types.gnutls_datum_t\
397
281
        (ctypes.cast(ctypes.c_char_p(openpgp),
398
282
                     ctypes.POINTER(ctypes.c_ubyte)),
399
283
         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
284
    # 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)
 
285
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
 
286
        (crt,
 
287
         ctypes.byref(datum),
 
288
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
408
289
    # New buffer for the fingerprint
409
290
    buffer = ctypes.create_string_buffer(20)
410
291
    buffer_length = ctypes.c_size_t()
426
307
    Note: This will run in its own forked process."""
427
308
    
428
309
    def handle(self):
429
 
        logger.info(u"TCP connection from: %s",
 
310
        logger.debug(u"TCP connection from: %s",
430
311
                     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.
 
312
        session = gnutls.connection.ClientSession(self.request,
 
313
                                                  gnutls.connection.\
 
314
                                                  X509Credentials())
447
315
        
448
316
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
449
317
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
450
318
        #                "+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"]
 
319
        priority = "SECURE256"
 
320
        
455
321
        gnutls.library.functions.gnutls_priority_set_direct\
456
322
            (session._c_object, priority, None);
457
323
        
458
324
        try:
459
325
            session.handshake()
460
326
        except gnutls.errors.GNUTLSError, error:
461
 
            logger.warning(u"Handshake failed: %s", error)
 
327
            logger.debug(u"Handshake failed: %s", error)
462
328
            # Do not run session.bye() here: the session is not
463
329
            # established.  Just abandon the request.
464
330
            return
465
331
        try:
466
332
            fpr = fingerprint(peer_certificate(session))
467
333
        except (TypeError, gnutls.errors.GNUTLSError), error:
468
 
            logger.warning(u"Bad certificate: %s", error)
 
334
            logger.debug(u"Bad certificate: %s", error)
469
335
            session.bye()
470
336
            return
471
337
        logger.debug(u"Fingerprint: %s", fpr)
472
338
        client = None
473
 
        for c in self.server.clients:
 
339
        for c in clients:
474
340
            if c.fingerprint == fpr:
475
341
                client = c
476
342
                break
477
 
        if not client:
478
 
            logger.warning(u"Client not found for fingerprint: %s",
479
 
                           fpr)
480
 
            session.bye()
481
 
            return
482
343
        # Have to check if client.still_valid(), since it is possible
483
344
        # that the client timed out while establishing the GnuTLS
484
345
        # session.
485
 
        if not client.still_valid():
486
 
            logger.warning(u"Client %(name)s is invalid",
487
 
                           vars(client))
 
346
        if (not client) or (not client.still_valid()):
 
347
            if client:
 
348
                logger.debug(u"Client %(name)s is invalid",
 
349
                             vars(client))
 
350
            else:
 
351
                logger.debug(u"Client not found for fingerprint: %s",
 
352
                             fpr)
488
353
            session.bye()
489
354
            return
490
355
        sent_size = 0
500
365
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
501
366
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
502
367
    Attributes:
503
 
        settings:       Server settings
 
368
        options:        Command line options
504
369
        clients:        Set() of Client objects
505
370
    """
506
371
    address_family = socket.AF_INET6
507
372
    def __init__(self, *args, **kwargs):
508
 
        if "settings" in kwargs:
509
 
            self.settings = kwargs["settings"]
510
 
            del kwargs["settings"]
 
373
        if "options" in kwargs:
 
374
            self.options = kwargs["options"]
 
375
            del kwargs["options"]
511
376
        if "clients" in kwargs:
512
377
            self.clients = kwargs["clients"]
513
378
            del kwargs["clients"]
516
381
        """This overrides the normal server_bind() function
517
382
        to bind to an interface if one was specified, and also NOT to
518
383
        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)
 
384
        if self.options.interface:
 
385
            if not hasattr(socket, "SO_BINDTODEVICE"):
 
386
                # From /usr/include/asm-i486/socket.h
 
387
                socket.SO_BINDTODEVICE = 25
522
388
            try:
523
389
                self.socket.setsockopt(socket.SOL_SOCKET,
524
 
                                       SO_BINDTODEVICE,
525
 
                                       self.settings["interface"])
 
390
                                       socket.SO_BINDTODEVICE,
 
391
                                       self.options.interface)
526
392
            except socket.error, error:
527
393
                if error[0] == errno.EPERM:
528
 
                    logger.error(u"No permission to"
529
 
                                 u" bind to interface %s",
530
 
                                 self.settings["interface"])
 
394
                    logger.warning(u"No permission to"
 
395
                                   u" bind to interface %s",
 
396
                                   self.options.interface)
531
397
                else:
532
398
                    raise error
533
399
        # Only bind(2) the socket if we really need to.
536
402
                in6addr_any = "::"
537
403
                self.server_address = (in6addr_any,
538
404
                                       self.server_address[1])
539
 
            elif not self.server_address[1]:
 
405
            elif self.server_address[1] is None:
540
406
                self.server_address = (self.server_address[0],
541
407
                                       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
408
            return super(type(self), self).server_bind()
550
409
 
551
410
 
583
442
    return delta
584
443
 
585
444
 
 
445
def add_service():
 
446
    """From the Avahi server example code"""
 
447
    global group, serviceName, serviceType, servicePort, serviceTXT, \
 
448
           domain, host
 
449
    if group is None:
 
450
        group = dbus.Interface(
 
451
                bus.get_object( avahi.DBUS_NAME,
 
452
                                server.EntryGroupNew()),
 
453
                avahi.DBUS_INTERFACE_ENTRY_GROUP)
 
454
        group.connect_to_signal('StateChanged',
 
455
                                entry_group_state_changed)
 
456
    logger.debug(u"Adding service '%s' of type '%s' ...",
 
457
                 serviceName, serviceType)
 
458
    
 
459
    group.AddService(
 
460
            serviceInterface,           # interface
 
461
            avahi.PROTO_INET6,          # protocol
 
462
            dbus.UInt32(0),             # flags
 
463
            serviceName, serviceType,
 
464
            domain, host,
 
465
            dbus.UInt16(servicePort),
 
466
            avahi.string_array_to_txt_array(serviceTXT))
 
467
    group.Commit()
 
468
 
 
469
 
 
470
def remove_service():
 
471
    """From the Avahi server example code"""
 
472
    global group
 
473
    
 
474
    if not group is None:
 
475
        group.Reset()
 
476
 
 
477
 
586
478
def server_state_changed(state):
587
 
    """Derived from the Avahi example code"""
 
479
    """From the Avahi server example code"""
588
480
    if state == avahi.SERVER_COLLISION:
589
 
        logger.error(u"Server name collision")
590
 
        service.remove()
 
481
        logger.warning(u"Server name collision")
 
482
        remove_service()
591
483
    elif state == avahi.SERVER_RUNNING:
592
 
        service.add()
 
484
        add_service()
593
485
 
594
486
 
595
487
def entry_group_state_changed(state, error):
596
 
    """Derived from the Avahi example code"""
 
488
    """From the Avahi server example code"""
 
489
    global serviceName, server, rename_count
 
490
    
597
491
    logger.debug(u"state change: %i", state)
598
492
    
599
493
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
600
494
        logger.debug(u"Service established.")
601
495
    elif state == avahi.ENTRY_GROUP_COLLISION:
602
 
        logger.warning(u"Service name collision.")
603
 
        service.rename()
 
496
        
 
497
        rename_count = rename_count - 1
 
498
        if rename_count > 0:
 
499
            name = server.GetAlternativeServiceName(name)
 
500
            logger.warning(u"Service name collision, "
 
501
                           u"changing name to '%s' ...", name)
 
502
            remove_service()
 
503
            add_service()
 
504
            
 
505
        else:
 
506
            logger.error(u"No suitable service name found "
 
507
                         u"after %i retries, exiting.",
 
508
                         n_rename)
 
509
            main_loop.quit()
604
510
    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))
 
511
        logger.error(u"Error in group state changed %s",
 
512
                     unicode(error))
 
513
        main_loop.quit()
 
514
        return
 
515
 
608
516
 
609
517
def if_nametoindex(interface):
610
 
    """Call the C function if_nametoindex(), or equivalent"""
611
 
    global if_nametoindex
 
518
    """Call the C function if_nametoindex()"""
612
519
    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
 
520
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
 
521
        return libc.if_nametoindex(interface)
617
522
    except (OSError, AttributeError):
618
523
        if "struct" not in sys.modules:
619
524
            import struct
620
525
        if "fcntl" not in sys.modules:
621
526
            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
 
def main():
658
 
    global main_loop_started
659
 
    main_loop_started = False
660
 
    
661
 
    parser = OptionParser(version = "%%prog %s" % version)
 
527
        SIOCGIFINDEX = 0x8933      # From /usr/include/linux/sockios.h
 
528
        s = socket.socket()
 
529
        ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
 
530
                            struct.pack("16s16x", interface))
 
531
        s.close()
 
532
        interface_index = struct.unpack("I", ifreq[16:20])[0]
 
533
        return interface_index
 
534
 
 
535
 
 
536
if __name__ == '__main__':
 
537
    parser = OptionParser()
662
538
    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",
 
539
                      default=None, metavar="IF",
 
540
                      help="Bind to interface IF")
 
541
    parser.add_option("--cert", type="string", default="cert.pem",
 
542
                      metavar="FILE",
 
543
                      help="Public key certificate PEM file to use")
 
544
    parser.add_option("--key", type="string", default="key.pem",
 
545
                      metavar="FILE",
 
546
                      help="Private key PEM file to use")
 
547
    parser.add_option("--ca", type="string", default="ca.pem",
 
548
                      metavar="FILE",
 
549
                      help="Certificate Authority certificate PEM file to use")
 
550
    parser.add_option("--crl", type="string", default="crl.pem",
 
551
                      metavar="FILE",
 
552
                      help="Certificate Revokation List PEM file to use")
 
553
    parser.add_option("-p", "--port", type="int", default=None,
667
554
                      help="Port number to receive requests on")
 
555
    parser.add_option("--timeout", type="string", # Parsed later
 
556
                      default="1h",
 
557
                      help="Amount of downtime allowed for clients")
 
558
    parser.add_option("--interval", type="string", # Parsed later
 
559
                      default="5m",
 
560
                      help="How often to check that a client is up")
668
561
    parser.add_option("--check", action="store_true", default=False,
669
562
                      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")
 
563
    parser.add_option("--debug", action="store_true", default=False,
 
564
                      help="Debug mode")
681
565
    (options, args) = parser.parse_args()
682
566
    
683
567
    if options.check:
685
569
        doctest.testmod()
686
570
        sys.exit()
687
571
    
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
 
572
    # Parse the time arguments
 
573
    try:
 
574
        options.timeout = string_to_delta(options.timeout)
 
575
    except ValueError:
 
576
        parser.error("option --timeout: Unparseable time")
 
577
    try:
 
578
        options.interval = string_to_delta(options.interval)
 
579
    except ValueError:
 
580
        parser.error("option --interval: Unparseable time")
 
581
    
 
582
    # Parse config file
 
583
    defaults = { "checker": "sleep 1; fping -q -- %%(fqdn)s" }
 
584
    client_config = ConfigParser.SafeConfigParser(defaults)
 
585
    #client_config.readfp(open("secrets.conf"), "secrets.conf")
 
586
    client_config.read("mandos-clients.conf")
 
587
    
 
588
    # From the Avahi server example code
751
589
    DBusGMainLoop(set_as_default=True )
752
590
    main_loop = gobject.MainLoop()
753
591
    bus = dbus.SystemBus()
756
594
            avahi.DBUS_INTERFACE_SERVER )
757
595
    # End of Avahi example code
758
596
    
 
597
    debug = options.debug
 
598
    
759
599
    clients = Set()
760
600
    def remove_from_clients(client):
761
601
        clients.remove(client)
762
602
        if not clients:
763
 
            logger.critical(u"No clients left, exiting")
764
 
            sys.exit()
 
603
            logger.debug(u"No clients left, exiting")
 
604
            main_loop.quit()
765
605
    
766
 
    clients.update(Set(Client(name = section,
 
606
    clients.update(Set(Client(name=section, options=options,
767
607
                              stop_hook = remove_from_clients,
768
 
                              config
769
 
                              = dict(client_config.items(section)))
 
608
                              **(dict(client_config\
 
609
                                      .items(section))))
770
610
                       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
611
    for client in clients:
812
612
        client.start()
813
613
    
814
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
815
 
                                 server_settings["port"]),
 
614
    tcp_server = IPv6_TCPServer((None, options.port),
816
615
                                tcp_handler,
817
 
                                settings=server_settings,
 
616
                                options=options,
818
617
                                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
 
    
 
618
    # Find out what random port we got
 
619
    servicePort = tcp_server.socket.getsockname()[1]
 
620
    logger.debug(u"Now listening on port %d", servicePort)
 
621
    
 
622
    if options.interface is not None:
 
623
        serviceInterface = if_nametoindex(options.interface)
 
624
    
 
625
    # From the Avahi server example code
 
626
    server.connect_to_signal("StateChanged", server_state_changed)
 
627
    server_state_changed(server.GetState())
 
628
    # End of Avahi example code
 
629
    
 
630
    gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
 
631
                         lambda *args, **kwargs:
 
632
                         tcp_server.handle_request(*args[2:],
 
633
                                                   **kwargs) or True)
826
634
    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
635
        main_loop.run()
844
 
    except AvahiError, error:
845
 
        logger.critical(u"AvahiError: %s" + unicode(error))
846
 
        sys.exit(1)
847
636
    except KeyboardInterrupt:
848
 
        if debug:
849
 
            print
 
637
        print
 
638
    
 
639
    # Cleanup here
850
640
 
851
 
if __name__ == '__main__':
852
 
    main()
 
641
    # From the Avahi server example code
 
642
    if not group is None:
 
643
        group.Free()
 
644
    # End of Avahi example code
 
645
    
 
646
    for client in clients:
 
647
        client.stop_hook = None
 
648
        client.stop()