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  • Committer: Teddy Hogeborn
  • Date: 2008-07-21 23:18:02 UTC
  • mfrom: (15.1.5 mandos) (15.1.5 mandos)
  • Revision ID: teddy@fukt.bsnet.se-20080721231802-0emzdsxkfy457p9u
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# This program is partly derived from an example program for an Avahi
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# service publisher, downloaded from
8
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".
 
9
# following functions: "add_service", "remove_service",
 
10
# "server_state_changed", "entry_group_state_changed", and some lines
 
11
# in "main".
12
12
13
 
# Everything else is
14
 
# Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
 
13
# Everything else is Copyright © 2007-2008 Teddy Hogeborn and Björn
 
14
# Påhlsson.
15
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16
16
# This program is free software: you can redistribute it and/or modify
17
17
# it under the terms of the GNU General Public License as published by
26
26
# You should have received a copy of the GNU General Public License
27
27
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
28
28
29
 
# Contact the authors at <mandos@fukt.bsnet.se>.
 
29
# Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
 
30
# <https://www.fukt.bsnet.se/~teddy/>.
30
31
31
32
 
32
33
from __future__ import division
61
62
from dbus.mainloop.glib import DBusGMainLoop
62
63
import ctypes
63
64
 
64
 
version = "1.0"
 
65
# Brief description of the operation of this program:
 
66
 
67
# This server announces itself as a Zeroconf service.  Connecting
 
68
# clients use the TLS protocol, with the unusual quirk that this
 
69
# server program acts as a TLS "client" while the connecting clients
 
70
# acts as a TLS "server".  The clients (acting as a TLS "server") must
 
71
# supply an OpenPGP certificate, and the fingerprint of this
 
72
# certificate is used by this server to look up (in a list read from a
 
73
# file at start time) which binary blob to give the client.  No other
 
74
# authentication or authorization is done by this server.
 
75
 
65
76
 
66
77
logger = logging.Logger('mandos')
67
78
syslogger = logging.handlers.SysLogHandler\
68
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
69
 
             address = "/dev/log")
 
79
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON)
70
80
syslogger.setFormatter(logging.Formatter\
71
 
                        ('Mandos: %(levelname)s: %(message)s'))
 
81
                        ('%(levelname)s: %(message)s'))
72
82
logger.addHandler(syslogger)
73
 
 
74
 
console = logging.StreamHandler()
75
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
76
 
                                       ' %(message)s'))
77
 
logger.addHandler(console)
78
 
 
79
 
class AvahiError(Exception):
80
 
    def __init__(self, value):
81
 
        self.value = value
82
 
    def __str__(self):
83
 
        return repr(self.value)
84
 
 
85
 
class AvahiServiceError(AvahiError):
86
 
    pass
87
 
 
88
 
class AvahiGroupError(AvahiError):
89
 
    pass
90
 
 
91
 
 
92
 
class AvahiService(object):
93
 
    """An Avahi (Zeroconf) service.
94
 
    Attributes:
95
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
96
 
               Used to optionally bind to the specified interface.
97
 
    name: string; Example: 'Mandos'
98
 
    type: string; Example: '_mandos._tcp'.
99
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
100
 
    port: integer; what port to announce
101
 
    TXT: list of strings; TXT record for the service
102
 
    domain: string; Domain to publish on, default to .local if empty.
103
 
    host: string; Host to publish records for, default is localhost
104
 
    max_renames: integer; maximum number of renames
105
 
    rename_count: integer; counter so we only rename after collisions
106
 
                  a sensible number of times
107
 
    """
108
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
109
 
                 type = None, port = None, TXT = None, domain = "",
110
 
                 host = "", max_renames = 32768):
111
 
        self.interface = interface
112
 
        self.name = name
113
 
        self.type = type
114
 
        self.port = port
115
 
        if TXT is None:
116
 
            self.TXT = []
117
 
        else:
118
 
            self.TXT = TXT
119
 
        self.domain = domain
120
 
        self.host = host
121
 
        self.rename_count = 0
122
 
        self.max_renames = max_renames
123
 
    def rename(self):
124
 
        """Derived from the Avahi example code"""
125
 
        if self.rename_count >= self.max_renames:
126
 
            logger.critical(u"No suitable service name found after %i"
127
 
                            u" retries, exiting.", rename_count)
128
 
            raise AvahiServiceError("Too many renames")
129
 
        self.name = server.GetAlternativeServiceName(self.name)
130
 
        logger.info(u"Changing name to %r ...", str(self.name))
131
 
        syslogger.setFormatter(logging.Formatter\
132
 
                               ('Mandos (%s): %%(levelname)s:'
133
 
                               ' %%(message)s' % self.name))
134
 
        self.remove()
135
 
        self.add()
136
 
        self.rename_count += 1
137
 
    def remove(self):
138
 
        """Derived from the Avahi example code"""
139
 
        if group is not None:
140
 
            group.Reset()
141
 
    def add(self):
142
 
        """Derived from the Avahi example code"""
143
 
        global group
144
 
        if group is None:
145
 
            group = dbus.Interface\
146
 
                    (bus.get_object(avahi.DBUS_NAME,
147
 
                                    server.EntryGroupNew()),
148
 
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
149
 
            group.connect_to_signal('StateChanged',
150
 
                                    entry_group_state_changed)
151
 
        logger.debug(u"Adding service '%s' of type '%s' ...",
152
 
                     service.name, service.type)
153
 
        group.AddService(
154
 
                self.interface,         # interface
155
 
                avahi.PROTO_INET6,      # protocol
156
 
                dbus.UInt32(0),         # flags
157
 
                self.name, self.type,
158
 
                self.domain, self.host,
159
 
                dbus.UInt16(self.port),
160
 
                avahi.string_array_to_txt_array(self.TXT))
161
 
        group.Commit()
162
 
 
 
83
del syslogger
 
84
 
 
85
# This variable is used to optionally bind to a specified interface.
 
86
# It is a global variable to fit in with the other variables from the
 
87
# Avahi example code.
 
88
serviceInterface = avahi.IF_UNSPEC
163
89
# From the Avahi example code:
164
 
group = None                            # our entry group
 
90
serviceName = "Mandos"
 
91
serviceType = "_mandos._tcp" # http://www.dns-sd.org/ServiceTypes.html
 
92
servicePort = None                      # Not known at startup
 
93
serviceTXT = []                         # TXT record for the service
 
94
domain = ""                  # Domain to publish on, default to .local
 
95
host = ""          # Host to publish records for, default to localhost
 
96
group = None #our entry group
 
97
rename_count = 12       # Counter so we only rename after collisions a
 
98
                        # sensible number of times
165
99
# End of Avahi example code
166
100
 
167
101
 
172
106
    fingerprint: string (40 or 32 hexadecimal digits); used to
173
107
                 uniquely identify the client
174
108
    secret:    bytestring; sent verbatim (over TLS) to client
175
 
    host:      string; available for use by the checker command
176
 
    created:   datetime.datetime(); object creation, not client host
177
 
    last_checked_ok: datetime.datetime() or None if not yet checked OK
178
 
    timeout:   datetime.timedelta(); How long from last_checked_ok
179
 
                                     until this client is invalid
 
109
    fqdn:      string (FQDN); available for use by the checker command
 
110
    created:   datetime.datetime()
 
111
    last_seen: datetime.datetime() or None if not yet seen
 
112
    timeout:   datetime.timedelta(); How long from last_seen until
 
113
                                     this client is invalid
180
114
    interval:  datetime.timedelta(); How often to start a new checker
181
115
    stop_hook: If set, called by stop() as stop_hook(self)
182
116
    checker:   subprocess.Popen(); a running checker process used
183
117
                                   to see if the client lives.
184
 
                                   'None' if no process is running.
 
118
                                   Is None if no process is running.
185
119
    checker_initiator_tag: a gobject event source tag, or None
186
120
    stop_initiator_tag:    - '' -
187
121
    checker_callback_tag:  - '' -
188
122
    checker_command: string; External command which is run to check if
189
 
                     client lives.  %() expansions are done at
 
123
                     client lives.  %()s expansions are done at
190
124
                     runtime with vars(self) as dict, so that for
191
125
                     instance %(name)s can be used in the command.
192
126
    Private attibutes:
193
127
    _timeout: Real variable for 'timeout'
194
128
    _interval: Real variable for 'interval'
195
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
 
129
    _timeout_milliseconds: Used by gobject.timeout_add()
196
130
    _interval_milliseconds: - '' -
197
131
    """
198
132
    def _set_timeout(self, timeout):
218
152
    interval = property(lambda self: self._interval,
219
153
                        _set_interval)
220
154
    del _set_interval
221
 
    def __init__(self, name = None, stop_hook=None, config={}):
222
 
        """Note: the 'checker' key in 'config' sets the
223
 
        'checker_command' attribute and *not* the 'checker'
224
 
        attribute."""
 
155
    def __init__(self, name=None, options=None, stop_hook=None,
 
156
                 fingerprint=None, secret=None, secfile=None,
 
157
                 fqdn=None, timeout=None, interval=-1, checker=None):
 
158
        """Note: the 'checker' argument sets the 'checker_command'
 
159
        attribute and not the 'checker' attribute.."""
225
160
        self.name = name
226
 
        logger.debug(u"Creating client %r", self.name)
227
 
        # Uppercase and remove spaces from fingerprint for later
228
 
        # comparison purposes with return value from the fingerprint()
229
 
        # function
230
 
        self.fingerprint = config["fingerprint"].upper()\
231
 
                           .replace(u" ", u"")
232
 
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
233
 
        if "secret" in config:
234
 
            self.secret = config["secret"].decode(u"base64")
235
 
        elif "secfile" in config:
236
 
            sf = open(config["secfile"])
 
161
        # Uppercase and remove spaces from fingerprint
 
162
        # for later comparison purposes with return value of
 
163
        # the fingerprint() function
 
164
        self.fingerprint = fingerprint.upper().replace(u" ", u"")
 
165
        if secret:
 
166
            self.secret = secret.decode(u"base64")
 
167
        elif secfile:
 
168
            sf = open(secfile)
237
169
            self.secret = sf.read()
238
170
            sf.close()
239
171
        else:
240
 
            raise TypeError(u"No secret or secfile for client %s"
241
 
                            % self.name)
242
 
        self.host = config.get("host", "")
 
172
            raise RuntimeError(u"No secret or secfile for client %s"
 
173
                               % self.name)
 
174
        self.fqdn = fqdn                # string
243
175
        self.created = datetime.datetime.now()
244
 
        self.last_checked_ok = None
245
 
        self.timeout = string_to_delta(config["timeout"])
246
 
        self.interval = string_to_delta(config["interval"])
 
176
        self.last_seen = None
 
177
        if timeout is None:
 
178
            self.timeout = options.timeout
 
179
        else:
 
180
            self.timeout = string_to_delta(timeout)
 
181
        if interval == -1:
 
182
            self.interval = options.interval
 
183
        else:
 
184
            self.interval = string_to_delta(interval)
247
185
        self.stop_hook = stop_hook
248
186
        self.checker = None
249
187
        self.checker_initiator_tag = None
250
188
        self.stop_initiator_tag = None
251
189
        self.checker_callback_tag = None
252
 
        self.check_command = config["checker"]
 
190
        self.check_command = checker
253
191
    def start(self):
254
192
        """Start this client's checker and timeout hooks"""
255
193
        # Schedule a new checker to be started an 'interval' from now,
265
203
                                   self.stop)
266
204
    def stop(self):
267
205
        """Stop this client.
268
 
        The possibility that a client might be restarted is left open,
269
 
        but not currently used."""
 
206
        The possibility that this client might be restarted is left
 
207
        open, but not currently used."""
270
208
        # If this client doesn't have a secret, it is already stopped.
271
 
        if hasattr(self, "secret") and self.secret:
272
 
            logger.info(u"Stopping client %s", self.name)
 
209
        if self.secret:
 
210
            logger.debug(u"Stopping client %s", self.name)
273
211
            self.secret = None
274
212
        else:
275
213
            return False
276
 
        if getattr(self, "stop_initiator_tag", False):
 
214
        if hasattr(self, "stop_initiator_tag") \
 
215
               and self.stop_initiator_tag:
277
216
            gobject.source_remove(self.stop_initiator_tag)
278
217
            self.stop_initiator_tag = None
279
 
        if getattr(self, "checker_initiator_tag", False):
 
218
        if hasattr(self, "checker_initiator_tag") \
 
219
               and self.checker_initiator_tag:
280
220
            gobject.source_remove(self.checker_initiator_tag)
281
221
            self.checker_initiator_tag = None
282
222
        self.stop_checker()
294
234
        self.checker = None
295
235
        if os.WIFEXITED(condition) \
296
236
               and (os.WEXITSTATUS(condition) == 0):
297
 
            logger.info(u"Checker for %(name)s succeeded",
298
 
                        vars(self))
299
 
            self.last_checked_ok = now
 
237
            logger.debug(u"Checker for %(name)s succeeded",
 
238
                         vars(self))
 
239
            self.last_seen = now
300
240
            gobject.source_remove(self.stop_initiator_tag)
301
241
            self.stop_initiator_tag = gobject.timeout_add\
302
242
                                      (self._timeout_milliseconds,
305
245
            logger.warning(u"Checker for %(name)s crashed?",
306
246
                           vars(self))
307
247
        else:
308
 
            logger.info(u"Checker for %(name)s failed",
309
 
                        vars(self))
 
248
            logger.debug(u"Checker for %(name)s failed",
 
249
                         vars(self))
310
250
    def start_checker(self):
311
251
        """Start a new checker subprocess if one is not running.
312
252
        If a checker already exists, leave it running and do
321
261
        # is as it should be.
322
262
        if self.checker is None:
323
263
            try:
324
 
                # In case check_command has exactly one % operator
325
 
                command = self.check_command % self.host
 
264
                command = self.check_command % self.fqdn
326
265
            except TypeError:
327
 
                # Escape attributes for the shell
328
266
                escaped_attrs = dict((key, re.escape(str(val)))
329
267
                                     for key, val in
330
268
                                     vars(self).iteritems())
331
269
                try:
332
270
                    command = self.check_command % escaped_attrs
333
271
                except TypeError, error:
334
 
                    logger.error(u'Could not format string "%s":'
335
 
                                 u' %s', self.check_command, error)
 
272
                    logger.critical(u'Could not format string "%s":'
 
273
                                    u' %s', self.check_command, error)
336
274
                    return True # Try again later
337
275
            try:
338
 
                logger.info(u"Starting checker %r for %s",
339
 
                            command, self.name)
340
 
                self.checker = subprocess.Popen(command,
341
 
                                                close_fds=True,
342
 
                                                shell=True, cwd="/")
 
276
                logger.debug(u"Starting checker %r for %s",
 
277
                             command, self.name)
 
278
                self.checker = subprocess.\
 
279
                               Popen(command,
 
280
                                     close_fds=True, shell=True,
 
281
                                     cwd="/")
343
282
                self.checker_callback_tag = gobject.child_watch_add\
344
283
                                            (self.checker.pid,
345
284
                                             self.checker_callback)
353
292
        if self.checker_callback_tag:
354
293
            gobject.source_remove(self.checker_callback_tag)
355
294
            self.checker_callback_tag = None
356
 
        if getattr(self, "checker", None) is None:
 
295
        if not hasattr(self, "checker") or self.checker is None:
357
296
            return
358
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
 
297
        logger.debug("Stopping checker for %(name)s", vars(self))
359
298
        try:
360
299
            os.kill(self.checker.pid, signal.SIGTERM)
361
300
            #os.sleep(0.5)
362
301
            #if self.checker.poll() is None:
363
302
            #    os.kill(self.checker.pid, signal.SIGKILL)
364
303
        except OSError, error:
365
 
            if error.errno != errno.ESRCH: # No such process
 
304
            if error.errno != errno.ESRCH:
366
305
                raise
367
306
        self.checker = None
368
 
    def still_valid(self):
 
307
    def still_valid(self, now=None):
369
308
        """Has the timeout not yet passed for this client?"""
370
 
        now = datetime.datetime.now()
371
 
        if self.last_checked_ok is None:
 
309
        if now is None:
 
310
            now = datetime.datetime.now()
 
311
        if self.last_seen is None:
372
312
            return now < (self.created + self.timeout)
373
313
        else:
374
 
            return now < (self.last_checked_ok + self.timeout)
 
314
            return now < (self.last_seen + self.timeout)
375
315
 
376
316
 
377
317
def peer_certificate(session):
393
333
 
394
334
def fingerprint(openpgp):
395
335
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
 
336
    # New empty GnuTLS certificate
 
337
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
338
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
339
        (ctypes.byref(crt))
396
340
    # New GnuTLS "datum" with the OpenPGP public key
397
341
    datum = gnutls.library.types.gnutls_datum_t\
398
342
        (ctypes.cast(ctypes.c_char_p(openpgp),
399
343
                     ctypes.POINTER(ctypes.c_ubyte)),
400
344
         ctypes.c_uint(len(openpgp)))
401
 
    # New empty GnuTLS certificate
402
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
403
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
404
 
        (ctypes.byref(crt))
405
345
    # Import the OpenPGP public key into the certificate
406
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
407
 
                    (crt, ctypes.byref(datum),
408
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
 
346
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
 
347
        (crt,
 
348
         ctypes.byref(datum),
 
349
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
409
350
    # New buffer for the fingerprint
410
351
    buffer = ctypes.create_string_buffer(20)
411
352
    buffer_length = ctypes.c_size_t()
427
368
    Note: This will run in its own forked process."""
428
369
    
429
370
    def handle(self):
430
 
        logger.info(u"TCP connection from: %s",
 
371
        logger.debug(u"TCP connection from: %s",
431
372
                     unicode(self.client_address))
432
 
        session = gnutls.connection.ClientSession\
433
 
                  (self.request, gnutls.connection.X509Credentials())
434
 
        
435
 
        line = self.request.makefile().readline()
436
 
        logger.debug(u"Protocol version: %r", line)
437
 
        try:
438
 
            if int(line.strip().split()[0]) > 1:
439
 
                raise RuntimeError
440
 
        except (ValueError, IndexError, RuntimeError), error:
441
 
            logger.error(u"Unknown protocol version: %s", error)
442
 
            return
443
 
        
444
 
        # Note: gnutls.connection.X509Credentials is really a generic
445
 
        # GnuTLS certificate credentials object so long as no X.509
446
 
        # keys are added to it.  Therefore, we can use it here despite
447
 
        # using OpenPGP certificates.
 
373
        session = gnutls.connection.ClientSession(self.request,
 
374
                                                  gnutls.connection.\
 
375
                                                  X509Credentials())
448
376
        
449
377
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
450
378
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
451
379
        #                "+DHE-DSS"))
452
 
        priority = "NORMAL"             # Fallback default, since this
453
 
                                        # MUST be set.
454
 
        if self.server.settings["priority"]:
455
 
            priority = self.server.settings["priority"]
 
380
        priority = "SECURE256"
 
381
        
456
382
        gnutls.library.functions.gnutls_priority_set_direct\
457
383
            (session._c_object, priority, None);
458
384
        
459
385
        try:
460
386
            session.handshake()
461
387
        except gnutls.errors.GNUTLSError, error:
462
 
            logger.warning(u"Handshake failed: %s", error)
 
388
            logger.debug(u"Handshake failed: %s", error)
463
389
            # Do not run session.bye() here: the session is not
464
390
            # established.  Just abandon the request.
465
391
            return
466
392
        try:
467
393
            fpr = fingerprint(peer_certificate(session))
468
394
        except (TypeError, gnutls.errors.GNUTLSError), error:
469
 
            logger.warning(u"Bad certificate: %s", error)
 
395
            logger.debug(u"Bad certificate: %s", error)
470
396
            session.bye()
471
397
            return
472
398
        logger.debug(u"Fingerprint: %s", fpr)
475
401
            if c.fingerprint == fpr:
476
402
                client = c
477
403
                break
478
 
        if not client:
479
 
            logger.warning(u"Client not found for fingerprint: %s",
480
 
                           fpr)
481
 
            session.bye()
482
 
            return
483
404
        # Have to check if client.still_valid(), since it is possible
484
405
        # that the client timed out while establishing the GnuTLS
485
406
        # session.
486
 
        if not client.still_valid():
487
 
            logger.warning(u"Client %(name)s is invalid",
488
 
                           vars(client))
 
407
        if (not client) or (not client.still_valid()):
 
408
            if client:
 
409
                logger.debug(u"Client %(name)s is invalid",
 
410
                             vars(client))
 
411
            else:
 
412
                logger.debug(u"Client not found for fingerprint: %s",
 
413
                             fpr)
489
414
            session.bye()
490
415
            return
491
416
        sent_size = 0
501
426
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
502
427
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
503
428
    Attributes:
504
 
        settings:       Server settings
 
429
        options:        Command line options
505
430
        clients:        Set() of Client objects
506
431
    """
507
432
    address_family = socket.AF_INET6
508
433
    def __init__(self, *args, **kwargs):
509
 
        if "settings" in kwargs:
510
 
            self.settings = kwargs["settings"]
511
 
            del kwargs["settings"]
 
434
        if "options" in kwargs:
 
435
            self.options = kwargs["options"]
 
436
            del kwargs["options"]
512
437
        if "clients" in kwargs:
513
438
            self.clients = kwargs["clients"]
514
439
            del kwargs["clients"]
517
442
        """This overrides the normal server_bind() function
518
443
        to bind to an interface if one was specified, and also NOT to
519
444
        bind to an address or port if they were not specified."""
520
 
        if self.settings["interface"]:
521
 
            # 25 is from /usr/include/asm-i486/socket.h
522
 
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
 
445
        if self.options.interface:
 
446
            if not hasattr(socket, "SO_BINDTODEVICE"):
 
447
                # From /usr/include/asm-i486/socket.h
 
448
                socket.SO_BINDTODEVICE = 25
523
449
            try:
524
450
                self.socket.setsockopt(socket.SOL_SOCKET,
525
 
                                       SO_BINDTODEVICE,
526
 
                                       self.settings["interface"])
 
451
                                       socket.SO_BINDTODEVICE,
 
452
                                       self.options.interface)
527
453
            except socket.error, error:
528
454
                if error[0] == errno.EPERM:
529
 
                    logger.error(u"No permission to"
530
 
                                 u" bind to interface %s",
531
 
                                 self.settings["interface"])
 
455
                    logger.warning(u"No permission to"
 
456
                                   u" bind to interface %s",
 
457
                                   self.options.interface)
532
458
                else:
533
459
                    raise error
534
460
        # Only bind(2) the socket if we really need to.
537
463
                in6addr_any = "::"
538
464
                self.server_address = (in6addr_any,
539
465
                                       self.server_address[1])
540
 
            elif not self.server_address[1]:
 
466
            elif self.server_address[1] is None:
541
467
                self.server_address = (self.server_address[0],
542
468
                                       0)
543
 
#                 if self.settings["interface"]:
544
 
#                     self.server_address = (self.server_address[0],
545
 
#                                            0, # port
546
 
#                                            0, # flowinfo
547
 
#                                            if_nametoindex
548
 
#                                            (self.settings
549
 
#                                             ["interface"]))
550
469
            return super(type(self), self).server_bind()
551
470
 
552
471
 
584
503
    return delta
585
504
 
586
505
 
 
506
def add_service():
 
507
    """Derived from the Avahi example code"""
 
508
    global group, serviceName, serviceType, servicePort, serviceTXT, \
 
509
           domain, host
 
510
    if group is None:
 
511
        group = dbus.Interface(
 
512
                bus.get_object( avahi.DBUS_NAME,
 
513
                                server.EntryGroupNew()),
 
514
                avahi.DBUS_INTERFACE_ENTRY_GROUP)
 
515
        group.connect_to_signal('StateChanged',
 
516
                                entry_group_state_changed)
 
517
    logger.debug(u"Adding service '%s' of type '%s' ...",
 
518
                 serviceName, serviceType)
 
519
    
 
520
    group.AddService(
 
521
            serviceInterface,           # interface
 
522
            avahi.PROTO_INET6,          # protocol
 
523
            dbus.UInt32(0),             # flags
 
524
            serviceName, serviceType,
 
525
            domain, host,
 
526
            dbus.UInt16(servicePort),
 
527
            avahi.string_array_to_txt_array(serviceTXT))
 
528
    group.Commit()
 
529
 
 
530
 
 
531
def remove_service():
 
532
    """From the Avahi example code"""
 
533
    global group
 
534
    
 
535
    if not group is None:
 
536
        group.Reset()
 
537
 
 
538
 
587
539
def server_state_changed(state):
588
540
    """Derived from the Avahi example code"""
589
541
    if state == avahi.SERVER_COLLISION:
590
 
        logger.error(u"Server name collision")
591
 
        service.remove()
 
542
        logger.warning(u"Server name collision")
 
543
        remove_service()
592
544
    elif state == avahi.SERVER_RUNNING:
593
 
        service.add()
 
545
        add_service()
594
546
 
595
547
 
596
548
def entry_group_state_changed(state, error):
597
549
    """Derived from the Avahi example code"""
 
550
    global serviceName, server, rename_count
 
551
    
598
552
    logger.debug(u"state change: %i", state)
599
553
    
600
554
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
601
555
        logger.debug(u"Service established.")
602
556
    elif state == avahi.ENTRY_GROUP_COLLISION:
603
 
        logger.warning(u"Service name collision.")
604
 
        service.rename()
 
557
        
 
558
        rename_count = rename_count - 1
 
559
        if rename_count > 0:
 
560
            name = server.GetAlternativeServiceName(name)
 
561
            logger.warning(u"Service name collision, "
 
562
                           u"changing name to '%s' ...", name)
 
563
            remove_service()
 
564
            add_service()
 
565
            
 
566
        else:
 
567
            logger.error(u"No suitable service name found after %i"
 
568
                         u" retries, exiting.", n_rename)
 
569
            killme(1)
605
570
    elif state == avahi.ENTRY_GROUP_FAILURE:
606
 
        logger.critical(u"Error in group state changed %s",
607
 
                        unicode(error))
608
 
        raise AvahiGroupError("State changed: %s", str(error))
 
571
        logger.error(u"Error in group state changed %s",
 
572
                     unicode(error))
 
573
        killme(1)
 
574
 
609
575
 
610
576
def if_nametoindex(interface):
611
 
    """Call the C function if_nametoindex(), or equivalent"""
612
 
    global if_nametoindex
 
577
    """Call the C function if_nametoindex()"""
613
578
    try:
614
 
        if "ctypes.util" not in sys.modules:
615
 
            import ctypes.util
616
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
617
 
            (ctypes.util.find_library("c")).if_nametoindex
 
579
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
 
580
        return libc.if_nametoindex(interface)
618
581
    except (OSError, AttributeError):
619
582
        if "struct" not in sys.modules:
620
583
            import struct
621
584
        if "fcntl" not in sys.modules:
622
585
            import fcntl
623
 
        def if_nametoindex(interface):
624
 
            "Get an interface index the hard way, i.e. using fcntl()"
625
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
626
 
            s = socket.socket()
627
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
628
 
                                struct.pack("16s16x", interface))
629
 
            s.close()
630
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
631
 
            return interface_index
632
 
    return if_nametoindex(interface)
633
 
 
634
 
 
635
 
def daemon(nochdir = False, noclose = False):
 
586
        SIOCGIFINDEX = 0x8933      # From /usr/include/linux/sockios.h
 
587
        s = socket.socket()
 
588
        ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
 
589
                            struct.pack("16s16x", interface))
 
590
        s.close()
 
591
        interface_index = struct.unpack("I", ifreq[16:20])[0]
 
592
        return interface_index
 
593
 
 
594
 
 
595
def daemon(nochdir, noclose):
636
596
    """See daemon(3).  Standard BSD Unix function.
637
597
    This should really exist as os.daemon, but it doesn't (yet)."""
638
598
    if os.fork():
640
600
    os.setsid()
641
601
    if not nochdir:
642
602
        os.chdir("/")
643
 
    if os.fork():
644
 
        sys.exit()
645
603
    if not noclose:
646
604
        # Close all standard open file descriptors
647
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
 
605
        null = os.open("/dev/null", os.O_NOCTTY | os.O_RDWR)
648
606
        if not stat.S_ISCHR(os.fstat(null).st_mode):
649
607
            raise OSError(errno.ENODEV,
650
608
                          "/dev/null not a character device")
655
613
            os.close(null)
656
614
 
657
615
 
 
616
def killme(status = 0):
 
617
    logger.debug("Stopping server with exit status %d", status)
 
618
    exitstatus = status
 
619
    if main_loop_started:
 
620
        main_loop.quit()
 
621
    else:
 
622
        sys.exit(status)
 
623
 
 
624
 
658
625
def main():
 
626
    global exitstatus
 
627
    exitstatus = 0
659
628
    global main_loop_started
660
629
    main_loop_started = False
661
630
    
662
 
    parser = OptionParser(version = "%%prog %s" % version)
 
631
    parser = OptionParser()
663
632
    parser.add_option("-i", "--interface", type="string",
664
 
                      metavar="IF", help="Bind to interface IF")
665
 
    parser.add_option("-a", "--address", type="string",
 
633
                      default=None, metavar="IF",
 
634
                      help="Bind to interface IF")
 
635
    parser.add_option("-a", "--address", type="string", default=None,
666
636
                      help="Address to listen for requests on")
667
 
    parser.add_option("-p", "--port", type="int",
 
637
    parser.add_option("-p", "--port", type="int", default=None,
668
638
                      help="Port number to receive requests on")
 
639
    parser.add_option("--timeout", type="string", # Parsed later
 
640
                      default="1h",
 
641
                      help="Amount of downtime allowed for clients")
 
642
    parser.add_option("--interval", type="string", # Parsed later
 
643
                      default="5m",
 
644
                      help="How often to check that a client is up")
669
645
    parser.add_option("--check", action="store_true", default=False,
670
646
                      help="Run self-test")
671
 
    parser.add_option("--debug", action="store_true",
672
 
                      help="Debug mode; run in foreground and log to"
673
 
                      " terminal")
674
 
    parser.add_option("--priority", type="string", help="GnuTLS"
675
 
                      " priority string (see GnuTLS documentation)")
676
 
    parser.add_option("--servicename", type="string", metavar="NAME",
677
 
                      help="Zeroconf service name")
678
 
    parser.add_option("--configdir", type="string",
679
 
                      default="/etc/mandos", metavar="DIR",
680
 
                      help="Directory to search for configuration"
681
 
                      " files")
 
647
    parser.add_option("--debug", action="store_true", default=False,
 
648
                      help="Debug mode")
682
649
    (options, args) = parser.parse_args()
683
650
    
684
651
    if options.check:
686
653
        doctest.testmod()
687
654
        sys.exit()
688
655
    
689
 
    # Default values for config file for server-global settings
690
 
    server_defaults = { "interface": "",
691
 
                        "address": "",
692
 
                        "port": "",
693
 
                        "debug": "False",
694
 
                        "priority":
695
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
696
 
                        "servicename": "Mandos",
697
 
                        }
698
 
    
699
 
    # Parse config file for server-global settings
700
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
701
 
    del server_defaults
702
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
703
 
    # Convert the SafeConfigParser object to a dict
704
 
    server_settings = server_config.defaults()
705
 
    # Use getboolean on the boolean config option
706
 
    server_settings["debug"] = server_config.getboolean\
707
 
                               ("DEFAULT", "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"])
 
656
    # Parse the time arguments
 
657
    try:
 
658
        options.timeout = string_to_delta(options.timeout)
 
659
    except ValueError:
 
660
        parser.error("option --timeout: Unparseable time")
 
661
    try:
 
662
        options.interval = string_to_delta(options.interval)
 
663
    except ValueError:
 
664
        parser.error("option --interval: Unparseable time")
 
665
    
 
666
    # Parse config file
 
667
    defaults = { "checker": "fping -q -- %%(fqdn)s" }
 
668
    client_config = ConfigParser.SafeConfigParser(defaults)
 
669
    #client_config.readfp(open("global.conf"), "global.conf")
 
670
    client_config.read("mandos-clients.conf")
746
671
    
747
672
    global main_loop
748
673
    global bus
756
681
            avahi.DBUS_INTERFACE_SERVER )
757
682
    # End of Avahi example code
758
683
    
 
684
    debug = options.debug
 
685
    
 
686
    if debug:
 
687
        console = logging.StreamHandler()
 
688
        # console.setLevel(logging.DEBUG)
 
689
        console.setFormatter(logging.Formatter\
 
690
                             ('%(levelname)s: %(message)s'))
 
691
        logger.addHandler(console)
 
692
        del console
 
693
    
759
694
    clients = Set()
760
695
    def remove_from_clients(client):
761
696
        clients.remove(client)
762
697
        if not clients:
763
 
            logger.critical(u"No clients left, exiting")
764
 
            sys.exit()
 
698
            logger.debug(u"No clients left, exiting")
 
699
            killme()
765
700
    
766
 
    clients.update(Set(Client(name = section,
 
701
    clients.update(Set(Client(name=section, options=options,
767
702
                              stop_hook = remove_from_clients,
768
 
                              config
769
 
                              = dict(client_config.items(section)))
 
703
                              **(dict(client_config\
 
704
                                      .items(section))))
770
705
                       for section in client_config.sections()))
771
 
    if not clients:
772
 
        logger.critical(u"No clients defined")
773
 
        sys.exit(1)
774
706
    
775
707
    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())
 
708
        daemon(False, False)
789
709
    
790
710
    def cleanup():
791
711
        "Cleanup function; run on exit"
805
725
    
806
726
    if not debug:
807
727
        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())
 
728
    signal.signal(signal.SIGHUP, lambda signum, frame: killme())
 
729
    signal.signal(signal.SIGTERM, lambda signum, frame: killme())
810
730
    
811
731
    for client in clients:
812
732
        client.start()
813
733
    
814
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
815
 
                                 server_settings["port"]),
 
734
    tcp_server = IPv6_TCPServer((options.address, options.port),
816
735
                                tcp_handler,
817
 
                                settings=server_settings,
 
736
                                options=options,
818
737
                                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")
 
738
    # Find out what random port we got
 
739
    global servicePort
 
740
    servicePort = tcp_server.socket.getsockname()[1]
 
741
    logger.debug(u"Now listening on port %d", servicePort)
 
742
    
 
743
    if options.interface is not None:
 
744
        global serviceInterface
 
745
        serviceInterface = if_nametoindex(options.interface)
 
746
    
 
747
    # From the Avahi example code
 
748
    server.connect_to_signal("StateChanged", server_state_changed)
 
749
    try:
 
750
        server_state_changed(server.GetState())
 
751
    except dbus.exceptions.DBusException, error:
 
752
        logger.critical(u"DBusException: %s", error)
 
753
        killme(1)
 
754
    # End of Avahi example code
 
755
    
 
756
    gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
 
757
                         lambda *args, **kwargs:
 
758
                         tcp_server.handle_request(*args[2:],
 
759
                                                   **kwargs) or True)
 
760
    try:
 
761
        logger.debug("Starting main loop")
842
762
        main_loop_started = True
843
763
        main_loop.run()
844
 
    except AvahiError, error:
845
 
        logger.critical(u"AvahiError: %s" + unicode(error))
846
 
        sys.exit(1)
847
764
    except KeyboardInterrupt:
848
765
        if debug:
849
766
            print
 
767
    
 
768
    sys.exit(exitstatus)
850
769
 
851
770
if __name__ == '__main__':
852
771
    main()