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# This program is partly derived from an example program for an Avahi
7
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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
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31
32
 
32
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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
 
 
75
 
class AvahiError(Exception):
76
 
    def __init__(self, value):
77
 
        self.value = value
78
 
    def __str__(self):
79
 
        return repr(self.value)
80
 
 
81
 
class AvahiServiceError(AvahiError):
82
 
    pass
83
 
 
84
 
class AvahiGroupError(AvahiError):
85
 
    pass
86
 
 
87
 
 
88
 
class AvahiService(object):
89
 
    """An Avahi (Zeroconf) service.
90
 
    Attributes:
91
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
92
 
               Used to optionally bind to the specified interface.
93
 
    name: string; Example: 'Mandos'
94
 
    type: string; Example: '_mandos._tcp'.
95
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
96
 
    port: integer; what port to announce
97
 
    TXT: list of strings; TXT record for the service
98
 
    domain: string; Domain to publish on, default to .local if empty.
99
 
    host: string; Host to publish records for, default is localhost
100
 
    max_renames: integer; maximum number of renames
101
 
    rename_count: integer; counter so we only rename after collisions
102
 
                  a sensible number of times
103
 
    """
104
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
105
 
                 type = None, port = None, TXT = None, domain = "",
106
 
                 host = "", max_renames = 32768):
107
 
        self.interface = interface
108
 
        self.name = name
109
 
        self.type = type
110
 
        self.port = port
111
 
        if TXT is None:
112
 
            self.TXT = []
113
 
        else:
114
 
            self.TXT = TXT
115
 
        self.domain = domain
116
 
        self.host = host
117
 
        self.rename_count = 0
118
 
    def rename(self):
119
 
        """Derived from the Avahi example code"""
120
 
        if self.rename_count >= self.max_renames:
121
 
            logger.critical(u"No suitable service name found after %i"
122
 
                            u" retries, exiting.", rename_count)
123
 
            raise AvahiServiceError("Too many renames")
124
 
        name = server.GetAlternativeServiceName(name)
125
 
        logger.error(u"Changing name to %r ...", name)
126
 
        syslogger.setFormatter(logging.Formatter\
127
 
                               ('Mandos (%s): %%(levelname)s:'
128
 
                               ' %%(message)s' % name))
129
 
        self.remove()
130
 
        self.add()
131
 
        self.rename_count += 1
132
 
    def remove(self):
133
 
        """Derived from the Avahi example code"""
134
 
        if group is not None:
135
 
            group.Reset()
136
 
    def add(self):
137
 
        """Derived from the Avahi example code"""
138
 
        global group
139
 
        if group is None:
140
 
            group = dbus.Interface\
141
 
                    (bus.get_object(avahi.DBUS_NAME,
142
 
                                    server.EntryGroupNew()),
143
 
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
144
 
            group.connect_to_signal('StateChanged',
145
 
                                    entry_group_state_changed)
146
 
        logger.debug(u"Adding service '%s' of type '%s' ...",
147
 
                     service.name, service.type)
148
 
        group.AddService(
149
 
                self.interface,         # interface
150
 
                avahi.PROTO_INET6,      # protocol
151
 
                dbus.UInt32(0),         # flags
152
 
                self.name, self.type,
153
 
                self.domain, self.host,
154
 
                dbus.UInt16(self.port),
155
 
                avahi.string_array_to_txt_array(self.TXT))
156
 
        group.Commit()
157
 
 
 
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
158
89
# From the Avahi example code:
159
 
group = None                            # our entry group
 
90
serviceName = None
 
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
160
99
# End of Avahi example code
161
100
 
162
101
 
167
106
    fingerprint: string (40 or 32 hexadecimal digits); used to
168
107
                 uniquely identify the client
169
108
    secret:    bytestring; sent verbatim (over TLS) to client
170
 
    host:      string; available for use by the checker command
171
 
    created:   datetime.datetime(); object creation, not client host
172
 
    last_checked_ok: datetime.datetime() or None if not yet checked OK
173
 
    timeout:   datetime.timedelta(); How long from last_checked_ok
174
 
                                     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
175
114
    interval:  datetime.timedelta(); How often to start a new checker
176
115
    stop_hook: If set, called by stop() as stop_hook(self)
177
116
    checker:   subprocess.Popen(); a running checker process used
178
117
                                   to see if the client lives.
179
 
                                   'None' if no process is running.
 
118
                                   Is None if no process is running.
180
119
    checker_initiator_tag: a gobject event source tag, or None
181
120
    stop_initiator_tag:    - '' -
182
121
    checker_callback_tag:  - '' -
183
122
    checker_command: string; External command which is run to check if
184
 
                     client lives.  %() expansions are done at
 
123
                     client lives.  %()s expansions are done at
185
124
                     runtime with vars(self) as dict, so that for
186
125
                     instance %(name)s can be used in the command.
187
126
    Private attibutes:
188
127
    _timeout: Real variable for 'timeout'
189
128
    _interval: Real variable for 'interval'
190
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
 
129
    _timeout_milliseconds: Used by gobject.timeout_add()
191
130
    _interval_milliseconds: - '' -
192
131
    """
193
132
    def _set_timeout(self, timeout):
213
152
    interval = property(lambda self: self._interval,
214
153
                        _set_interval)
215
154
    del _set_interval
216
 
    def __init__(self, name = None, stop_hook=None, config={}):
217
 
        """Note: the 'checker' key in 'config' sets the
218
 
        'checker_command' attribute and *not* the 'checker'
219
 
        attribute."""
 
155
    def __init__(self, name=None, stop_hook=None, fingerprint=None,
 
156
                 secret=None, secfile=None, fqdn=None, timeout=None,
 
157
                 interval=-1, checker=None):
 
158
        """Note: the 'checker' argument sets the 'checker_command'
 
159
        attribute and not the 'checker' attribute.."""
220
160
        self.name = name
221
161
        logger.debug(u"Creating client %r", self.name)
222
 
        # Uppercase and remove spaces from fingerprint for later
223
 
        # comparison purposes with return value from the fingerprint()
224
 
        # function
225
 
        self.fingerprint = config["fingerprint"].upper()\
226
 
                           .replace(u" ", u"")
 
162
        # Uppercase and remove spaces from fingerprint
 
163
        # for later comparison purposes with return value of
 
164
        # the fingerprint() function
 
165
        self.fingerprint = fingerprint.upper().replace(u" ", u"")
227
166
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
228
 
        if "secret" in config:
229
 
            self.secret = config["secret"].decode(u"base64")
230
 
        elif "secfile" in config:
231
 
            sf = open(config["secfile"])
 
167
        if secret:
 
168
            self.secret = secret.decode(u"base64")
 
169
        elif secfile:
 
170
            sf = open(secfile)
232
171
            self.secret = sf.read()
233
172
            sf.close()
234
173
        else:
235
 
            raise TypeError(u"No secret or secfile for client %s"
236
 
                            % self.name)
237
 
        self.host = config.get("host", "")
 
174
            raise RuntimeError(u"No secret or secfile for client %s"
 
175
                               % self.name)
 
176
        self.fqdn = fqdn                # string
238
177
        self.created = datetime.datetime.now()
239
 
        self.last_checked_ok = None
240
 
        self.timeout = string_to_delta(config["timeout"])
241
 
        self.interval = string_to_delta(config["interval"])
 
178
        self.last_seen = None
 
179
        self.timeout = string_to_delta(timeout)
 
180
        self.interval = string_to_delta(interval)
242
181
        self.stop_hook = stop_hook
243
182
        self.checker = None
244
183
        self.checker_initiator_tag = None
245
184
        self.stop_initiator_tag = None
246
185
        self.checker_callback_tag = None
247
 
        self.check_command = config["checker"]
 
186
        self.check_command = checker
248
187
    def start(self):
249
188
        """Start this client's checker and timeout hooks"""
250
189
        # Schedule a new checker to be started an 'interval' from now,
260
199
                                   self.stop)
261
200
    def stop(self):
262
201
        """Stop this client.
263
 
        The possibility that a client might be restarted is left open,
264
 
        but not currently used."""
 
202
        The possibility that this client might be restarted is left
 
203
        open, but not currently used."""
265
204
        # If this client doesn't have a secret, it is already stopped.
266
 
        if hasattr(self, "secret") and self.secret:
267
 
            logger.info(u"Stopping client %s", self.name)
 
205
        if self.secret:
 
206
            logger.debug(u"Stopping client %s", self.name)
268
207
            self.secret = None
269
208
        else:
270
209
            return False
271
 
        if getattr(self, "stop_initiator_tag", False):
 
210
        if hasattr(self, "stop_initiator_tag") \
 
211
               and self.stop_initiator_tag:
272
212
            gobject.source_remove(self.stop_initiator_tag)
273
213
            self.stop_initiator_tag = None
274
 
        if getattr(self, "checker_initiator_tag", False):
 
214
        if hasattr(self, "checker_initiator_tag") \
 
215
               and self.checker_initiator_tag:
275
216
            gobject.source_remove(self.checker_initiator_tag)
276
217
            self.checker_initiator_tag = None
277
218
        self.stop_checker()
289
230
        self.checker = None
290
231
        if os.WIFEXITED(condition) \
291
232
               and (os.WEXITSTATUS(condition) == 0):
292
 
            logger.info(u"Checker for %(name)s succeeded",
293
 
                        vars(self))
294
 
            self.last_checked_ok = now
 
233
            logger.debug(u"Checker for %(name)s succeeded",
 
234
                         vars(self))
 
235
            self.last_seen = now
295
236
            gobject.source_remove(self.stop_initiator_tag)
296
237
            self.stop_initiator_tag = gobject.timeout_add\
297
238
                                      (self._timeout_milliseconds,
300
241
            logger.warning(u"Checker for %(name)s crashed?",
301
242
                           vars(self))
302
243
        else:
303
 
            logger.info(u"Checker for %(name)s failed",
304
 
                        vars(self))
 
244
            logger.debug(u"Checker for %(name)s failed",
 
245
                         vars(self))
305
246
    def start_checker(self):
306
247
        """Start a new checker subprocess if one is not running.
307
248
        If a checker already exists, leave it running and do
316
257
        # is as it should be.
317
258
        if self.checker is None:
318
259
            try:
319
 
                # In case check_command has exactly one % operator
320
 
                command = self.check_command % self.host
 
260
                command = self.check_command % self.fqdn
321
261
            except TypeError:
322
 
                # Escape attributes for the shell
323
262
                escaped_attrs = dict((key, re.escape(str(val)))
324
263
                                     for key, val in
325
264
                                     vars(self).iteritems())
326
265
                try:
327
266
                    command = self.check_command % escaped_attrs
328
267
                except TypeError, error:
329
 
                    logger.error(u'Could not format string "%s":'
330
 
                                 u' %s', self.check_command, error)
 
268
                    logger.critical(u'Could not format string "%s":'
 
269
                                    u' %s', self.check_command, error)
331
270
                    return True # Try again later
332
271
            try:
333
 
                logger.info(u"Starting checker %r for %s",
334
 
                            command, self.name)
335
 
                self.checker = subprocess.Popen(command,
336
 
                                                close_fds=True,
337
 
                                                shell=True, cwd="/")
 
272
                logger.debug(u"Starting checker %r for %s",
 
273
                             command, self.name)
 
274
                self.checker = subprocess.\
 
275
                               Popen(command,
 
276
                                     close_fds=True, shell=True,
 
277
                                     cwd="/")
338
278
                self.checker_callback_tag = gobject.child_watch_add\
339
279
                                            (self.checker.pid,
340
280
                                             self.checker_callback)
348
288
        if self.checker_callback_tag:
349
289
            gobject.source_remove(self.checker_callback_tag)
350
290
            self.checker_callback_tag = None
351
 
        if getattr(self, "checker", None) is None:
 
291
        if not hasattr(self, "checker") or self.checker is None:
352
292
            return
353
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
 
293
        logger.debug("Stopping checker for %(name)s", vars(self))
354
294
        try:
355
295
            os.kill(self.checker.pid, signal.SIGTERM)
356
296
            #os.sleep(0.5)
357
297
            #if self.checker.poll() is None:
358
298
            #    os.kill(self.checker.pid, signal.SIGKILL)
359
299
        except OSError, error:
360
 
            if error.errno != errno.ESRCH: # No such process
 
300
            if error.errno != errno.ESRCH:
361
301
                raise
362
302
        self.checker = None
363
 
    def still_valid(self):
 
303
    def still_valid(self, now=None):
364
304
        """Has the timeout not yet passed for this client?"""
365
 
        now = datetime.datetime.now()
366
 
        if self.last_checked_ok is None:
 
305
        if now is None:
 
306
            now = datetime.datetime.now()
 
307
        if self.last_seen is None:
367
308
            return now < (self.created + self.timeout)
368
309
        else:
369
 
            return now < (self.last_checked_ok + self.timeout)
 
310
            return now < (self.last_seen + self.timeout)
370
311
 
371
312
 
372
313
def peer_certificate(session):
388
329
 
389
330
def fingerprint(openpgp):
390
331
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
 
332
    # New empty GnuTLS certificate
 
333
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
334
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
335
        (ctypes.byref(crt))
391
336
    # New GnuTLS "datum" with the OpenPGP public key
392
337
    datum = gnutls.library.types.gnutls_datum_t\
393
338
        (ctypes.cast(ctypes.c_char_p(openpgp),
394
339
                     ctypes.POINTER(ctypes.c_ubyte)),
395
340
         ctypes.c_uint(len(openpgp)))
396
 
    # New empty GnuTLS certificate
397
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
398
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
399
 
        (ctypes.byref(crt))
400
341
    # Import the OpenPGP public key into the certificate
401
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
402
 
                    (crt, ctypes.byref(datum),
403
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
 
342
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
 
343
        (crt,
 
344
         ctypes.byref(datum),
 
345
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
404
346
    # New buffer for the fingerprint
405
347
    buffer = ctypes.create_string_buffer(20)
406
348
    buffer_length = ctypes.c_size_t()
422
364
    Note: This will run in its own forked process."""
423
365
    
424
366
    def handle(self):
425
 
        logger.info(u"TCP connection from: %s",
 
367
        logger.debug(u"TCP connection from: %s",
426
368
                     unicode(self.client_address))
427
 
        session = gnutls.connection.ClientSession\
428
 
                  (self.request, gnutls.connection.X509Credentials())
429
 
        
430
 
        line = self.request.makefile().readline()
431
 
        logger.debug(u"Protocol version: %r", line)
432
 
        try:
433
 
            if int(line.strip().split()[0]) > 1:
434
 
                raise RuntimeError
435
 
        except (ValueError, IndexError, RuntimeError), error:
436
 
            logger.error(u"Unknown protocol version: %s", error)
437
 
            return
438
 
        
439
 
        # Note: gnutls.connection.X509Credentials is really a generic
440
 
        # GnuTLS certificate credentials object so long as no X.509
441
 
        # keys are added to it.  Therefore, we can use it here despite
442
 
        # using OpenPGP certificates.
 
369
        session = gnutls.connection.ClientSession(self.request,
 
370
                                                  gnutls.connection.\
 
371
                                                  X509Credentials())
443
372
        
444
373
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
445
374
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
446
375
        #                "+DHE-DSS"))
447
 
        priority = "NORMAL"             # Fallback default, since this
448
 
                                        # MUST be set.
449
 
        if self.server.settings["priority"]:
450
 
            priority = self.server.settings["priority"]
 
376
        priority = "NORMAL"
 
377
        if self.server.options.priority:
 
378
            priority = self.server.options.priority
451
379
        gnutls.library.functions.gnutls_priority_set_direct\
452
380
            (session._c_object, priority, None);
453
381
        
454
382
        try:
455
383
            session.handshake()
456
384
        except gnutls.errors.GNUTLSError, error:
457
 
            logger.warning(u"Handshake failed: %s", error)
 
385
            logger.debug(u"Handshake failed: %s", error)
458
386
            # Do not run session.bye() here: the session is not
459
387
            # established.  Just abandon the request.
460
388
            return
461
389
        try:
462
390
            fpr = fingerprint(peer_certificate(session))
463
391
        except (TypeError, gnutls.errors.GNUTLSError), error:
464
 
            logger.warning(u"Bad certificate: %s", error)
 
392
            logger.debug(u"Bad certificate: %s", error)
465
393
            session.bye()
466
394
            return
467
395
        logger.debug(u"Fingerprint: %s", fpr)
470
398
            if c.fingerprint == fpr:
471
399
                client = c
472
400
                break
473
 
        if not client:
474
 
            logger.warning(u"Client not found for fingerprint: %s",
475
 
                           fpr)
476
 
            session.bye()
477
 
            return
478
401
        # Have to check if client.still_valid(), since it is possible
479
402
        # that the client timed out while establishing the GnuTLS
480
403
        # session.
481
 
        if not client.still_valid():
482
 
            logger.warning(u"Client %(name)s is invalid",
483
 
                           vars(client))
 
404
        if (not client) or (not client.still_valid()):
 
405
            if client:
 
406
                logger.debug(u"Client %(name)s is invalid",
 
407
                             vars(client))
 
408
            else:
 
409
                logger.debug(u"Client not found for fingerprint: %s",
 
410
                             fpr)
484
411
            session.bye()
485
412
            return
486
413
        sent_size = 0
496
423
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
497
424
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
498
425
    Attributes:
499
 
        settings:       Server settings
 
426
        options:        Command line options
500
427
        clients:        Set() of Client objects
501
428
    """
502
429
    address_family = socket.AF_INET6
503
430
    def __init__(self, *args, **kwargs):
504
 
        if "settings" in kwargs:
505
 
            self.settings = kwargs["settings"]
506
 
            del kwargs["settings"]
 
431
        if "options" in kwargs:
 
432
            self.options = kwargs["options"]
 
433
            del kwargs["options"]
507
434
        if "clients" in kwargs:
508
435
            self.clients = kwargs["clients"]
509
436
            del kwargs["clients"]
512
439
        """This overrides the normal server_bind() function
513
440
        to bind to an interface if one was specified, and also NOT to
514
441
        bind to an address or port if they were not specified."""
515
 
        if self.settings["interface"]:
516
 
            # 25 is from /usr/include/asm-i486/socket.h
517
 
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
 
442
        if self.options.interface:
 
443
            if not hasattr(socket, "SO_BINDTODEVICE"):
 
444
                # From /usr/include/asm-i486/socket.h
 
445
                socket.SO_BINDTODEVICE = 25
518
446
            try:
519
447
                self.socket.setsockopt(socket.SOL_SOCKET,
520
 
                                       SO_BINDTODEVICE,
521
 
                                       self.settings["interface"])
 
448
                                       socket.SO_BINDTODEVICE,
 
449
                                       self.options.interface)
522
450
            except socket.error, error:
523
451
                if error[0] == errno.EPERM:
524
 
                    logger.error(u"No permission to"
525
 
                                 u" bind to interface %s",
526
 
                                 self.settings["interface"])
 
452
                    logger.warning(u"No permission to"
 
453
                                   u" bind to interface %s",
 
454
                                   self.options.interface)
527
455
                else:
528
456
                    raise error
529
457
        # Only bind(2) the socket if we really need to.
532
460
                in6addr_any = "::"
533
461
                self.server_address = (in6addr_any,
534
462
                                       self.server_address[1])
535
 
            elif not self.server_address[1]:
 
463
            elif self.server_address[1] is None:
536
464
                self.server_address = (self.server_address[0],
537
465
                                       0)
538
 
#                 if self.settings["interface"]:
539
 
#                     self.server_address = (self.server_address[0],
540
 
#                                            0, # port
541
 
#                                            0, # flowinfo
542
 
#                                            if_nametoindex
543
 
#                                            (self.settings
544
 
#                                             ["interface"]))
545
466
            return super(type(self), self).server_bind()
546
467
 
547
468
 
579
500
    return delta
580
501
 
581
502
 
 
503
def add_service():
 
504
    """Derived from the Avahi example code"""
 
505
    global group, serviceName, serviceType, servicePort, serviceTXT, \
 
506
           domain, host
 
507
    if group is None:
 
508
        group = dbus.Interface(
 
509
                bus.get_object( avahi.DBUS_NAME,
 
510
                                server.EntryGroupNew()),
 
511
                avahi.DBUS_INTERFACE_ENTRY_GROUP)
 
512
        group.connect_to_signal('StateChanged',
 
513
                                entry_group_state_changed)
 
514
    logger.debug(u"Adding service '%s' of type '%s' ...",
 
515
                 serviceName, serviceType)
 
516
    
 
517
    group.AddService(
 
518
            serviceInterface,           # interface
 
519
            avahi.PROTO_INET6,          # protocol
 
520
            dbus.UInt32(0),             # flags
 
521
            serviceName, serviceType,
 
522
            domain, host,
 
523
            dbus.UInt16(servicePort),
 
524
            avahi.string_array_to_txt_array(serviceTXT))
 
525
    group.Commit()
 
526
 
 
527
 
 
528
def remove_service():
 
529
    """From the Avahi example code"""
 
530
    global group
 
531
    
 
532
    if not group is None:
 
533
        group.Reset()
 
534
 
 
535
 
582
536
def server_state_changed(state):
583
537
    """Derived from the Avahi example code"""
584
538
    if state == avahi.SERVER_COLLISION:
585
 
        logger.error(u"Server name collision")
586
 
        service.remove()
 
539
        logger.warning(u"Server name collision")
 
540
        remove_service()
587
541
    elif state == avahi.SERVER_RUNNING:
588
 
        service.add()
 
542
        add_service()
589
543
 
590
544
 
591
545
def entry_group_state_changed(state, error):
592
546
    """Derived from the Avahi example code"""
 
547
    global serviceName, server, rename_count
 
548
    
593
549
    logger.debug(u"state change: %i", state)
594
550
    
595
551
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
596
552
        logger.debug(u"Service established.")
597
553
    elif state == avahi.ENTRY_GROUP_COLLISION:
598
 
        logger.warning(u"Service name collision.")
599
 
        service.rename()
 
554
        
 
555
        rename_count = rename_count - 1
 
556
        if rename_count > 0:
 
557
            name = server.GetAlternativeServiceName(name)
 
558
            logger.warning(u"Service name collision, "
 
559
                           u"changing name to '%s' ...", name)
 
560
            remove_service()
 
561
            add_service()
 
562
            
 
563
        else:
 
564
            logger.error(u"No suitable service name found after %i"
 
565
                         u" retries, exiting.", n_rename)
 
566
            killme(1)
600
567
    elif state == avahi.ENTRY_GROUP_FAILURE:
601
 
        logger.critical(u"Error in group state changed %s",
602
 
                        unicode(error))
603
 
        raise AvahiGroupError("State changed: %s", str(error))
 
568
        logger.error(u"Error in group state changed %s",
 
569
                     unicode(error))
 
570
        killme(1)
 
571
 
604
572
 
605
573
def if_nametoindex(interface):
606
 
    """Call the C function if_nametoindex(), or equivalent"""
607
 
    global if_nametoindex
 
574
    """Call the C function if_nametoindex()"""
608
575
    try:
609
 
        if "ctypes.util" not in sys.modules:
610
 
            import ctypes.util
611
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
612
 
            (ctypes.util.find_library("c")).if_nametoindex
 
576
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
 
577
        return libc.if_nametoindex(interface)
613
578
    except (OSError, AttributeError):
614
579
        if "struct" not in sys.modules:
615
580
            import struct
616
581
        if "fcntl" not in sys.modules:
617
582
            import fcntl
618
 
        def if_nametoindex(interface):
619
 
            "Get an interface index the hard way, i.e. using fcntl()"
620
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
621
 
            s = socket.socket()
622
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
623
 
                                struct.pack("16s16x", interface))
624
 
            s.close()
625
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
626
 
            return interface_index
627
 
    return if_nametoindex(interface)
628
 
 
629
 
 
630
 
def daemon(nochdir = False, noclose = False):
 
583
        SIOCGIFINDEX = 0x8933      # From /usr/include/linux/sockios.h
 
584
        s = socket.socket()
 
585
        ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
 
586
                            struct.pack("16s16x", interface))
 
587
        s.close()
 
588
        interface_index = struct.unpack("I", ifreq[16:20])[0]
 
589
        return interface_index
 
590
 
 
591
 
 
592
def daemon(nochdir, noclose):
631
593
    """See daemon(3).  Standard BSD Unix function.
632
594
    This should really exist as os.daemon, but it doesn't (yet)."""
633
595
    if os.fork():
635
597
    os.setsid()
636
598
    if not nochdir:
637
599
        os.chdir("/")
638
 
    if os.fork():
639
 
        sys.exit()
640
600
    if not noclose:
641
601
        # Close all standard open file descriptors
642
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
 
602
        null = os.open("/dev/null", os.O_NOCTTY | os.O_RDWR)
643
603
        if not stat.S_ISCHR(os.fstat(null).st_mode):
644
604
            raise OSError(errno.ENODEV,
645
605
                          "/dev/null not a character device")
650
610
            os.close(null)
651
611
 
652
612
 
 
613
def killme(status = 0):
 
614
    logger.debug("Stopping server with exit status %d", status)
 
615
    exitstatus = status
 
616
    if main_loop_started:
 
617
        main_loop.quit()
 
618
    else:
 
619
        sys.exit(status)
 
620
 
 
621
 
653
622
def main():
 
623
    global exitstatus
 
624
    exitstatus = 0
654
625
    global main_loop_started
655
626
    main_loop_started = False
656
627
    
657
 
    parser = OptionParser(version = "Mandos server %s" % version)
 
628
    parser = OptionParser()
658
629
    parser.add_option("-i", "--interface", type="string",
659
 
                      metavar="IF", help="Bind to interface IF")
660
 
    parser.add_option("-a", "--address", type="string",
 
630
                      default=None, metavar="IF",
 
631
                      help="Bind to interface IF")
 
632
    parser.add_option("-a", "--address", type="string", default=None,
661
633
                      help="Address to listen for requests on")
662
 
    parser.add_option("-p", "--port", type="int",
 
634
    parser.add_option("-p", "--port", type="int", default=None,
663
635
                      help="Port number to receive requests on")
664
636
    parser.add_option("--check", action="store_true", default=False,
665
637
                      help="Run self-test")
666
 
    parser.add_option("--debug", action="store_true",
667
 
                      help="Debug mode; run in foreground and log to"
668
 
                      " terminal")
669
 
    parser.add_option("--priority", type="string", help="GnuTLS"
670
 
                      " priority string (see GnuTLS documentation)")
671
 
    parser.add_option("--servicename", type="string", metavar="NAME",
672
 
                      help="Zeroconf service name")
673
 
    parser.add_option("--configdir", type="string",
674
 
                      default="/etc/mandos", metavar="DIR",
675
 
                      help="Directory to search for configuration"
676
 
                      " files")
 
638
    parser.add_option("--debug", action="store_true", default=False,
 
639
                      help="Debug mode")
 
640
    parser.add_option("--priority", type="string",
 
641
                      default="SECURE256",
 
642
                      help="GnuTLS priority string"
 
643
                      " (see GnuTLS documentation)")
 
644
    parser.add_option("--servicename", type="string",
 
645
                      default="Mandos", help="Zeroconf service name")
677
646
    (options, args) = parser.parse_args()
678
647
    
679
648
    if options.check:
681
650
        doctest.testmod()
682
651
        sys.exit()
683
652
    
684
 
    # Default values for config file for server-global settings
685
 
    server_defaults = { "interface": "",
686
 
                        "address": "",
687
 
                        "port": "",
688
 
                        "debug": "False",
689
 
                        "priority":
690
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
691
 
                        "servicename": "Mandos",
692
 
                        }
693
 
    
694
 
    # Parse config file for server-global settings
695
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
696
 
    del server_defaults
697
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
698
 
    server_section = "server"
699
 
    # Convert the SafeConfigParser object to a dict
700
 
    server_settings = dict(server_config.items(server_section))
701
 
    # Use getboolean on the boolean config option
702
 
    server_settings["debug"] = server_config.getboolean\
703
 
                               (server_section, "debug")
704
 
    del server_config
705
 
    
706
 
    # Override the settings from the config file with command line
707
 
    # options, if set.
708
 
    for option in ("interface", "address", "port", "debug",
709
 
                   "priority", "servicename", "configdir"):
710
 
        value = getattr(options, option)
711
 
        if value is not None:
712
 
            server_settings[option] = value
713
 
    del options
714
 
    # Now we have our good server settings in "server_settings"
715
 
    
716
 
    debug = server_settings["debug"]
717
 
    
718
 
    if not debug:
719
 
        syslogger.setLevel(logging.WARNING)
720
 
    
721
 
    if server_settings["servicename"] != "Mandos":
722
 
        syslogger.setFormatter(logging.Formatter\
723
 
                               ('Mandos (%s): %%(levelname)s:'
724
 
                                ' %%(message)s'
725
 
                                % server_settings["servicename"]))
726
 
    
727
 
    # Parse config file with clients
728
 
    client_defaults = { "timeout": "1h",
729
 
                        "interval": "5m",
730
 
                        "checker": "fping -q -- %%(host)s",
731
 
                        }
732
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
733
 
    client_config.read(os.path.join(server_settings["configdir"],
734
 
                                    "clients.conf"))
735
 
    
736
 
    global service
737
 
    service = AvahiService(name = server_settings["servicename"],
738
 
                           type = "_mandos._tcp", );
739
 
    if server_settings["interface"]:
740
 
        service.interface = if_nametoindex(server_settings["interface"])
 
653
    # Parse config file
 
654
    defaults = { "timeout": "1h",
 
655
                 "interval": "5m",
 
656
                 "checker": "fping -q -- %%(fqdn)s",
 
657
                 }
 
658
    client_config = ConfigParser.SafeConfigParser(defaults)
 
659
    #client_config.readfp(open("global.conf"), "global.conf")
 
660
    client_config.read("mandos-clients.conf")
 
661
    
 
662
    global serviceName
 
663
    serviceName = options.servicename;
741
664
    
742
665
    global main_loop
743
666
    global bus
751
674
            avahi.DBUS_INTERFACE_SERVER )
752
675
    # End of Avahi example code
753
676
    
 
677
    debug = options.debug
 
678
    
754
679
    if debug:
755
680
        console = logging.StreamHandler()
756
681
        # console.setLevel(logging.DEBUG)
763
688
    def remove_from_clients(client):
764
689
        clients.remove(client)
765
690
        if not clients:
766
 
            logger.critical(u"No clients left, exiting")
767
 
            sys.exit()
 
691
            logger.debug(u"No clients left, exiting")
 
692
            killme()
768
693
    
769
 
    clients.update(Set(Client(name = section,
 
694
    clients.update(Set(Client(name=section,
770
695
                              stop_hook = remove_from_clients,
771
 
                              config
772
 
                              = dict(client_config.items(section)))
 
696
                              **(dict(client_config\
 
697
                                      .items(section))))
773
698
                       for section in client_config.sections()))
774
 
    if not clients:
775
 
        logger.critical(u"No clients defined")
776
 
        sys.exit(1)
777
699
    
778
700
    if not debug:
779
 
        daemon()
780
 
    
781
 
    pidfilename = "/var/run/mandos/mandos.pid"
782
 
    pid = os.getpid()
783
 
    try:
784
 
        pidfile = open(pidfilename, "w")
785
 
        pidfile.write(str(pid) + "\n")
786
 
        pidfile.close()
787
 
        del pidfile
788
 
    except IOError, err:
789
 
        logger.error(u"Could not write %s file with PID %d",
790
 
                     pidfilename, os.getpid())
 
701
        daemon(False, False)
791
702
    
792
703
    def cleanup():
793
704
        "Cleanup function; run on exit"
807
718
    
808
719
    if not debug:
809
720
        signal.signal(signal.SIGINT, signal.SIG_IGN)
810
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
811
 
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
 
721
    signal.signal(signal.SIGHUP, lambda signum, frame: killme())
 
722
    signal.signal(signal.SIGTERM, lambda signum, frame: killme())
812
723
    
813
724
    for client in clients:
814
725
        client.start()
815
726
    
816
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
817
 
                                 server_settings["port"]),
 
727
    tcp_server = IPv6_TCPServer((options.address, options.port),
818
728
                                tcp_handler,
819
 
                                settings=server_settings,
 
729
                                options=options,
820
730
                                clients=clients)
821
 
    # Find out what port we got
822
 
    service.port = tcp_server.socket.getsockname()[1]
823
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
824
 
                u" scope_id %d" % tcp_server.socket.getsockname())
825
 
    
826
 
    #service.interface = tcp_server.socket.getsockname()[3]
827
 
    
828
 
    try:
829
 
        # From the Avahi example code
830
 
        server.connect_to_signal("StateChanged", server_state_changed)
831
 
        try:
832
 
            server_state_changed(server.GetState())
833
 
        except dbus.exceptions.DBusException, error:
834
 
            logger.critical(u"DBusException: %s", error)
835
 
            sys.exit(1)
836
 
        # End of Avahi example code
837
 
        
838
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
839
 
                             lambda *args, **kwargs:
840
 
                             tcp_server.handle_request\
841
 
                             (*args[2:], **kwargs) or True)
842
 
        
843
 
        logger.debug(u"Starting main loop")
 
731
    # Find out what random port we got
 
732
    global servicePort
 
733
    servicePort = tcp_server.socket.getsockname()[1]
 
734
    logger.debug(u"Now listening on port %d", servicePort)
 
735
    
 
736
    if options.interface is not None:
 
737
        global serviceInterface
 
738
        serviceInterface = if_nametoindex(options.interface)
 
739
    
 
740
    # From the Avahi example code
 
741
    server.connect_to_signal("StateChanged", server_state_changed)
 
742
    try:
 
743
        server_state_changed(server.GetState())
 
744
    except dbus.exceptions.DBusException, error:
 
745
        logger.critical(u"DBusException: %s", error)
 
746
        killme(1)
 
747
    # End of Avahi example code
 
748
    
 
749
    gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
 
750
                         lambda *args, **kwargs:
 
751
                         tcp_server.handle_request(*args[2:],
 
752
                                                   **kwargs) or True)
 
753
    try:
 
754
        logger.debug("Starting main loop")
844
755
        main_loop_started = True
845
756
        main_loop.run()
846
 
    except AvahiError, error:
847
 
        logger.critical(u"AvahiError: %s" + unicode(error))
848
 
        sys.exit(1)
849
757
    except KeyboardInterrupt:
850
758
        if debug:
851
759
            print
 
760
    
 
761
    sys.exit(exitstatus)
852
762
 
853
763
if __name__ == '__main__':
854
764
    main()