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server.py
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# This program is partly derived from an example program for an Avahi
7
7
# service publisher, downloaded from
8
8
# <http://avahi.org/wiki/PythonPublishExample>.  This includes the
9
 
# following functions: "add_service", "remove_service",
 
9
# following functions: "AvahiService.add", "AvahiService.remove",
10
10
# "server_state_changed", "entry_group_state_changed", and some lines
11
11
# in "main".
12
12
# 
13
 
# Everything else is Copyright © 2007-2008 Teddy Hogeborn and Björn
14
 
# Påhlsson.
 
13
# Everything else is
 
14
# Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
15
15
# 
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 <https://www.fukt.bsnet.se/~belorn/> and
30
 
# <https://www.fukt.bsnet.se/~teddy/>.
 
29
# Contact the authors at <mandos@fukt.bsnet.se>.
31
30
# 
32
31
 
33
32
from __future__ import division
66
65
# 
67
66
# This server announces itself as a Zeroconf service.  Connecting
68
67
# 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
 
68
# server program acts as a TLS "client" while a connecting client acts
 
69
# as a TLS "server".  The client (acting as a TLS "server") must
71
70
# supply an OpenPGP certificate, and the fingerprint of this
72
71
# certificate is used by this server to look up (in a list read from a
73
72
# file at start time) which binary blob to give the client.  No other
82
81
logger.addHandler(syslogger)
83
82
del syslogger
84
83
 
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
 
84
 
 
85
class AvahiError(Exception):
 
86
    def __init__(self, value):
 
87
        self.value = value
 
88
    def __str__(self):
 
89
        return repr(self.value)
 
90
 
 
91
class AvahiServiceError(AvahiError):
 
92
    pass
 
93
 
 
94
class AvahiGroupError(AvahiError):
 
95
    pass
 
96
 
 
97
 
 
98
class AvahiService(object):
 
99
    """An Avahi (Zeroconf) service.
 
100
    Attributes:
 
101
    interface: integer; avahi.IF_UNSPEC or an interface index.
 
102
               Used to optionally bind to the specified interface.
 
103
    name: string; Example: 'Mandos'
 
104
    type: string; Example: '_mandos._tcp'.
 
105
                  See <http://www.dns-sd.org/ServiceTypes.html>
 
106
    port: integer; what port to announce
 
107
    TXT: list of strings; TXT record for the service
 
108
    domain: string; Domain to publish on, default to .local if empty.
 
109
    host: string; Host to publish records for, default is localhost
 
110
    max_renames: integer; maximum number of renames
 
111
    rename_count: integer; counter so we only rename after collisions
 
112
                  a sensible number of times
 
113
    """
 
114
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
 
115
                 type = None, port = None, TXT = None, domain = "",
 
116
                 host = "", max_renames = 12):
 
117
        self.interface = interface
 
118
        self.name = name
 
119
        self.type = type
 
120
        self.port = port
 
121
        if TXT is None:
 
122
            self.TXT = []
 
123
        else:
 
124
            self.TXT = TXT
 
125
        self.domain = domain
 
126
        self.host = host
 
127
        self.rename_count = 0
 
128
    def rename(self):
 
129
        """Derived from the Avahi example code"""
 
130
        if self.rename_count >= self.max_renames:
 
131
            logger.critical(u"No suitable service name found after %i"
 
132
                            u" retries, exiting.", rename_count)
 
133
            raise AvahiServiceError("Too many renames")
 
134
        name = server.GetAlternativeServiceName(name)
 
135
        logger.error(u"Changing name to %r ...", name)
 
136
        self.remove()
 
137
        self.add()
 
138
        self.rename_count += 1
 
139
    def remove(self):
 
140
        """Derived from the Avahi example code"""
 
141
        if group is not None:
 
142
            group.Reset()
 
143
    def add(self):
 
144
        """Derived from the Avahi example code"""
 
145
        global group
 
146
        if group is None:
 
147
            group = dbus.Interface\
 
148
                    (bus.get_object(avahi.DBUS_NAME,
 
149
                                    server.EntryGroupNew()),
 
150
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
 
151
            group.connect_to_signal('StateChanged',
 
152
                                    entry_group_state_changed)
 
153
        logger.debug(u"Adding service '%s' of type '%s' ...",
 
154
                     service.name, service.type)
 
155
        group.AddService(
 
156
                self.interface,         # interface
 
157
                avahi.PROTO_INET6,      # protocol
 
158
                dbus.UInt32(0),         # flags
 
159
                self.name, self.type,
 
160
                self.domain, self.host,
 
161
                dbus.UInt16(self.port),
 
162
                avahi.string_array_to_txt_array(self.TXT))
 
163
        group.Commit()
 
164
 
89
165
# From the Avahi example code:
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
 
166
group = None                            # our entry group
99
167
# End of Avahi example code
100
168
 
101
169
 
107
175
                 uniquely identify the client
108
176
    secret:    bytestring; sent verbatim (over TLS) to client
109
177
    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
 
178
    created:   datetime.datetime(); object creation, not client host
 
179
    last_checked_ok: datetime.datetime() or None if not yet checked OK
 
180
    timeout:   datetime.timedelta(); How long from last_checked_ok
 
181
                                     until this client is invalid
114
182
    interval:  datetime.timedelta(); How often to start a new checker
115
183
    stop_hook: If set, called by stop() as stop_hook(self)
116
184
    checker:   subprocess.Popen(); a running checker process used
117
185
                                   to see if the client lives.
118
 
                                   Is None if no process is running.
 
186
                                   'None' if no process is running.
119
187
    checker_initiator_tag: a gobject event source tag, or None
120
188
    stop_initiator_tag:    - '' -
121
189
    checker_callback_tag:  - '' -
122
190
    checker_command: string; External command which is run to check if
123
 
                     client lives.  %()s expansions are done at
 
191
                     client lives.  %() expansions are done at
124
192
                     runtime with vars(self) as dict, so that for
125
193
                     instance %(name)s can be used in the command.
126
194
    Private attibutes:
127
195
    _timeout: Real variable for 'timeout'
128
196
    _interval: Real variable for 'interval'
129
 
    _timeout_milliseconds: Used by gobject.timeout_add()
 
197
    _timeout_milliseconds: Used when calling gobject.timeout_add()
130
198
    _interval_milliseconds: - '' -
131
199
    """
132
200
    def _set_timeout(self, timeout):
152
220
    interval = property(lambda self: self._interval,
153
221
                        _set_interval)
154
222
    del _set_interval
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.."""
 
223
    def __init__(self, name = None, stop_hook=None, config={}):
 
224
        """Note: the 'checker' key in 'config' sets the
 
225
        'checker_command' attribute and *not* the 'checker'
 
226
        attribute."""
160
227
        self.name = name
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)
 
228
        logger.debug(u"Creating client %r", self.name)
 
229
        # Uppercase and remove spaces from fingerprint for later
 
230
        # comparison purposes with return value from the fingerprint()
 
231
        # function
 
232
        self.fingerprint = config["fingerprint"].upper()\
 
233
                           .replace(u" ", u"")
 
234
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
 
235
        if "secret" in config:
 
236
            self.secret = config["secret"].decode(u"base64")
 
237
        elif "secfile" in config:
 
238
            sf = open(config["secfile"])
169
239
            self.secret = sf.read()
170
240
            sf.close()
171
241
        else:
172
 
            raise RuntimeError(u"No secret or secfile for client %s"
173
 
                               % self.name)
174
 
        self.fqdn = fqdn                # string
 
242
            raise TypeError(u"No secret or secfile for client %s"
 
243
                            % self.name)
 
244
        self.fqdn = config.get("fqdn", "")
175
245
        self.created = datetime.datetime.now()
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)
 
246
        self.last_checked_ok = None
 
247
        self.timeout = string_to_delta(config["timeout"])
 
248
        self.interval = string_to_delta(config["interval"])
185
249
        self.stop_hook = stop_hook
186
250
        self.checker = None
187
251
        self.checker_initiator_tag = None
188
252
        self.stop_initiator_tag = None
189
253
        self.checker_callback_tag = None
190
 
        self.check_command = checker
 
254
        self.check_command = config["checker"]
191
255
    def start(self):
192
256
        """Start this client's checker and timeout hooks"""
193
257
        # Schedule a new checker to be started an 'interval' from now,
203
267
                                   self.stop)
204
268
    def stop(self):
205
269
        """Stop this client.
206
 
        The possibility that this client might be restarted is left
207
 
        open, but not currently used."""
 
270
        The possibility that a client might be restarted is left open,
 
271
        but not currently used."""
208
272
        # If this client doesn't have a secret, it is already stopped.
209
273
        if self.secret:
210
 
            logger.debug(u"Stopping client %s", self.name)
 
274
            logger.info(u"Stopping client %s", self.name)
211
275
            self.secret = None
212
276
        else:
213
277
            return False
214
 
        if hasattr(self, "stop_initiator_tag") \
215
 
               and self.stop_initiator_tag:
 
278
        if getattr(self, "stop_initiator_tag", False):
216
279
            gobject.source_remove(self.stop_initiator_tag)
217
280
            self.stop_initiator_tag = None
218
 
        if hasattr(self, "checker_initiator_tag") \
219
 
               and self.checker_initiator_tag:
 
281
        if getattr(self, "checker_initiator_tag", False):
220
282
            gobject.source_remove(self.checker_initiator_tag)
221
283
            self.checker_initiator_tag = None
222
284
        self.stop_checker()
234
296
        self.checker = None
235
297
        if os.WIFEXITED(condition) \
236
298
               and (os.WEXITSTATUS(condition) == 0):
237
 
            logger.debug(u"Checker for %(name)s succeeded",
238
 
                         vars(self))
239
 
            self.last_seen = now
 
299
            logger.info(u"Checker for %(name)s succeeded",
 
300
                        vars(self))
 
301
            self.last_checked_ok = now
240
302
            gobject.source_remove(self.stop_initiator_tag)
241
303
            self.stop_initiator_tag = gobject.timeout_add\
242
304
                                      (self._timeout_milliseconds,
245
307
            logger.warning(u"Checker for %(name)s crashed?",
246
308
                           vars(self))
247
309
        else:
248
 
            logger.debug(u"Checker for %(name)s failed",
249
 
                         vars(self))
 
310
            logger.info(u"Checker for %(name)s failed",
 
311
                        vars(self))
250
312
    def start_checker(self):
251
313
        """Start a new checker subprocess if one is not running.
252
314
        If a checker already exists, leave it running and do
261
323
        # is as it should be.
262
324
        if self.checker is None:
263
325
            try:
 
326
                # In case check_command has exactly one % operator
264
327
                command = self.check_command % self.fqdn
265
328
            except TypeError:
 
329
                # Escape attributes for the shell
266
330
                escaped_attrs = dict((key, re.escape(str(val)))
267
331
                                     for key, val in
268
332
                                     vars(self).iteritems())
269
333
                try:
270
334
                    command = self.check_command % escaped_attrs
271
335
                except TypeError, error:
272
 
                    logger.critical(u'Could not format string "%s":'
273
 
                                    u' %s', self.check_command, error)
 
336
                    logger.error(u'Could not format string "%s":'
 
337
                                 u' %s', self.check_command, error)
274
338
                    return True # Try again later
275
339
            try:
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="/")
 
340
                logger.info(u"Starting checker %r for %s",
 
341
                            command, self.name)
 
342
                self.checker = subprocess.Popen(command,
 
343
                                                close_fds=True,
 
344
                                                shell=True, cwd="/")
282
345
                self.checker_callback_tag = gobject.child_watch_add\
283
346
                                            (self.checker.pid,
284
347
                                             self.checker_callback)
292
355
        if self.checker_callback_tag:
293
356
            gobject.source_remove(self.checker_callback_tag)
294
357
            self.checker_callback_tag = None
295
 
        if not hasattr(self, "checker") or self.checker is None:
 
358
        if getattr(self, "checker", None) is None:
296
359
            return
297
360
        logger.debug("Stopping checker for %(name)s", vars(self))
298
361
        try:
301
364
            #if self.checker.poll() is None:
302
365
            #    os.kill(self.checker.pid, signal.SIGKILL)
303
366
        except OSError, error:
304
 
            if error.errno != errno.ESRCH:
 
367
            if error.errno != errno.ESRCH: # No such process
305
368
                raise
306
369
        self.checker = None
307
 
    def still_valid(self, now=None):
 
370
    def still_valid(self):
308
371
        """Has the timeout not yet passed for this client?"""
309
 
        if now is None:
310
 
            now = datetime.datetime.now()
311
 
        if self.last_seen is None:
 
372
        now = datetime.datetime.now()
 
373
        if self.last_checked_ok is None:
312
374
            return now < (self.created + self.timeout)
313
375
        else:
314
 
            return now < (self.last_seen + self.timeout)
 
376
            return now < (self.last_checked_ok + self.timeout)
315
377
 
316
378
 
317
379
def peer_certificate(session):
333
395
 
334
396
def fingerprint(openpgp):
335
397
    "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))
340
398
    # New GnuTLS "datum" with the OpenPGP public key
341
399
    datum = gnutls.library.types.gnutls_datum_t\
342
400
        (ctypes.cast(ctypes.c_char_p(openpgp),
343
401
                     ctypes.POINTER(ctypes.c_ubyte)),
344
402
         ctypes.c_uint(len(openpgp)))
 
403
    # New empty GnuTLS certificate
 
404
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
405
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
406
        (ctypes.byref(crt))
345
407
    # Import the OpenPGP public key into the certificate
346
 
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
347
 
        (crt,
348
 
         ctypes.byref(datum),
349
 
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
 
408
    gnutls.library.functions.gnutls_openpgp_crt_import\
 
409
                    (crt, ctypes.byref(datum),
 
410
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
350
411
    # New buffer for the fingerprint
351
412
    buffer = ctypes.create_string_buffer(20)
352
413
    buffer_length = ctypes.c_size_t()
368
429
    Note: This will run in its own forked process."""
369
430
    
370
431
    def handle(self):
371
 
        logger.debug(u"TCP connection from: %s",
 
432
        logger.info(u"TCP connection from: %s",
372
433
                     unicode(self.client_address))
373
 
        session = gnutls.connection.ClientSession(self.request,
374
 
                                                  gnutls.connection.\
375
 
                                                  X509Credentials())
 
434
        session = gnutls.connection.ClientSession\
 
435
                  (self.request, gnutls.connection.X509Credentials())
 
436
        
 
437
        line = self.request.makefile().readline()
 
438
        logger.debug(u"Protocol version: %r", line)
 
439
        try:
 
440
            if int(line.strip().split()[0]) > 1:
 
441
                raise RuntimeError
 
442
        except (ValueError, IndexError, RuntimeError), error:
 
443
            logger.error(u"Unknown protocol version: %s", error)
 
444
            return
 
445
        
 
446
        # Note: gnutls.connection.X509Credentials is really a generic
 
447
        # GnuTLS certificate credentials object so long as no X.509
 
448
        # keys are added to it.  Therefore, we can use it here despite
 
449
        # using OpenPGP certificates.
376
450
        
377
451
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
378
452
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
379
453
        #                "+DHE-DSS"))
380
 
        priority = "SECURE256"
381
 
        
 
454
        priority = "NORMAL"             # Fallback default, since this
 
455
                                        # MUST be set.
 
456
        if self.server.settings["priority"]:
 
457
            priority = self.server.settings["priority"]
382
458
        gnutls.library.functions.gnutls_priority_set_direct\
383
459
            (session._c_object, priority, None);
384
460
        
385
461
        try:
386
462
            session.handshake()
387
463
        except gnutls.errors.GNUTLSError, error:
388
 
            logger.debug(u"Handshake failed: %s", error)
 
464
            logger.warning(u"Handshake failed: %s", error)
389
465
            # Do not run session.bye() here: the session is not
390
466
            # established.  Just abandon the request.
391
467
            return
392
468
        try:
393
469
            fpr = fingerprint(peer_certificate(session))
394
470
        except (TypeError, gnutls.errors.GNUTLSError), error:
395
 
            logger.debug(u"Bad certificate: %s", error)
 
471
            logger.warning(u"Bad certificate: %s", error)
396
472
            session.bye()
397
473
            return
398
474
        logger.debug(u"Fingerprint: %s", fpr)
401
477
            if c.fingerprint == fpr:
402
478
                client = c
403
479
                break
 
480
        if not client:
 
481
            logger.warning(u"Client not found for fingerprint: %s",
 
482
                           fpr)
 
483
            session.bye()
 
484
            return
404
485
        # Have to check if client.still_valid(), since it is possible
405
486
        # that the client timed out while establishing the GnuTLS
406
487
        # session.
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)
 
488
        if not client.still_valid():
 
489
            logger.warning(u"Client %(name)s is invalid",
 
490
                           vars(client))
414
491
            session.bye()
415
492
            return
416
493
        sent_size = 0
426
503
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
427
504
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
428
505
    Attributes:
429
 
        options:        Command line options
 
506
        settings:       Server settings
430
507
        clients:        Set() of Client objects
431
508
    """
432
509
    address_family = socket.AF_INET6
433
510
    def __init__(self, *args, **kwargs):
434
 
        if "options" in kwargs:
435
 
            self.options = kwargs["options"]
436
 
            del kwargs["options"]
 
511
        if "settings" in kwargs:
 
512
            self.settings = kwargs["settings"]
 
513
            del kwargs["settings"]
437
514
        if "clients" in kwargs:
438
515
            self.clients = kwargs["clients"]
439
516
            del kwargs["clients"]
442
519
        """This overrides the normal server_bind() function
443
520
        to bind to an interface if one was specified, and also NOT to
444
521
        bind to an address or port if they were not specified."""
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
 
522
        if self.settings["interface"]:
 
523
            # 25 is from /usr/include/asm-i486/socket.h
 
524
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
449
525
            try:
450
526
                self.socket.setsockopt(socket.SOL_SOCKET,
451
 
                                       socket.SO_BINDTODEVICE,
452
 
                                       self.options.interface)
 
527
                                       SO_BINDTODEVICE,
 
528
                                       self.settings["interface"])
453
529
            except socket.error, error:
454
530
                if error[0] == errno.EPERM:
455
 
                    logger.warning(u"No permission to"
456
 
                                   u" bind to interface %s",
457
 
                                   self.options.interface)
 
531
                    logger.error(u"No permission to"
 
532
                                 u" bind to interface %s",
 
533
                                 self.settings["interface"])
458
534
                else:
459
535
                    raise error
460
536
        # Only bind(2) the socket if we really need to.
503
579
    return delta
504
580
 
505
581
 
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
 
 
539
582
def server_state_changed(state):
540
583
    """Derived from the Avahi example code"""
541
584
    if state == avahi.SERVER_COLLISION:
542
 
        logger.warning(u"Server name collision")
543
 
        remove_service()
 
585
        logger.error(u"Server name collision")
 
586
        service.remove()
544
587
    elif state == avahi.SERVER_RUNNING:
545
 
        add_service()
 
588
        service.add()
546
589
 
547
590
 
548
591
def entry_group_state_changed(state, error):
549
592
    """Derived from the Avahi example code"""
550
 
    global serviceName, server, rename_count
551
 
    
552
593
    logger.debug(u"state change: %i", state)
553
594
    
554
595
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
555
596
        logger.debug(u"Service established.")
556
597
    elif state == avahi.ENTRY_GROUP_COLLISION:
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)
 
598
        logger.warning(u"Service name collision.")
 
599
        service.rename()
570
600
    elif state == avahi.ENTRY_GROUP_FAILURE:
571
 
        logger.error(u"Error in group state changed %s",
572
 
                     unicode(error))
573
 
        killme(1)
574
 
 
 
601
        logger.critical(u"Error in group state changed %s",
 
602
                        unicode(error))
 
603
        raise AvahiGroupError("State changed: %s", str(error))
575
604
 
576
605
def if_nametoindex(interface):
577
 
    """Call the C function if_nametoindex()"""
 
606
    """Call the C function if_nametoindex(), or equivalent"""
 
607
    global if_nametoindex
578
608
    try:
579
 
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
580
 
        return libc.if_nametoindex(interface)
 
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
581
613
    except (OSError, AttributeError):
582
614
        if "struct" not in sys.modules:
583
615
            import struct
584
616
        if "fcntl" not in sys.modules:
585
617
            import fcntl
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
 
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)
593
628
 
594
629
 
595
630
def daemon(nochdir, noclose):
602
637
        os.chdir("/")
603
638
    if not noclose:
604
639
        # Close all standard open file descriptors
605
 
        null = os.open("/dev/null", os.O_NOCTTY | os.O_RDWR)
 
640
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
606
641
        if not stat.S_ISCHR(os.fstat(null).st_mode):
607
642
            raise OSError(errno.ENODEV,
608
643
                          "/dev/null not a character device")
613
648
            os.close(null)
614
649
 
615
650
 
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
 
 
625
651
def main():
626
 
    global exitstatus
627
 
    exitstatus = 0
628
652
    global main_loop_started
629
653
    main_loop_started = False
630
654
    
631
655
    parser = OptionParser()
632
656
    parser.add_option("-i", "--interface", type="string",
633
 
                      default=None, metavar="IF",
634
 
                      help="Bind to interface IF")
635
 
    parser.add_option("-a", "--address", type="string", default=None,
 
657
                      metavar="IF", help="Bind to interface IF")
 
658
    parser.add_option("-a", "--address", type="string",
636
659
                      help="Address to listen for requests on")
637
 
    parser.add_option("-p", "--port", type="int", default=None,
 
660
    parser.add_option("-p", "--port", type="int",
638
661
                      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")
645
662
    parser.add_option("--check", action="store_true", default=False,
646
663
                      help="Run self-test")
647
664
    parser.add_option("--debug", action="store_true", default=False,
648
 
                      help="Debug mode")
 
665
                      help="Debug mode; run in foreground and log to"
 
666
                      " terminal")
 
667
    parser.add_option("--priority", type="string", help="GnuTLS"
 
668
                      " priority string (see GnuTLS documentation)")
 
669
    parser.add_option("--servicename", type="string", metavar="NAME",
 
670
                      help="Zeroconf service name")
 
671
    parser.add_option("--configdir", type="string",
 
672
                      default="/etc/mandos", metavar="DIR",
 
673
                      help="Directory to search for configuration"
 
674
                      " files")
649
675
    (options, args) = parser.parse_args()
650
676
    
651
677
    if options.check:
653
679
        doctest.testmod()
654
680
        sys.exit()
655
681
    
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")
 
682
    # Default values for config file for server-global settings
 
683
    server_defaults = { "interface": "",
 
684
                        "address": "",
 
685
                        "port": "",
 
686
                        "debug": "False",
 
687
                        "priority":
 
688
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
 
689
                        "servicename": "Mandos",
 
690
                        }
 
691
    
 
692
    # Parse config file for server-global settings
 
693
    server_config = ConfigParser.SafeConfigParser(server_defaults)
 
694
    del server_defaults
 
695
    server_config.read(os.path.join(options.configdir, "server.conf"))
 
696
    server_section = "server"
 
697
    # Convert the SafeConfigParser object to a dict
 
698
    server_settings = dict(server_config.items(server_section))
 
699
    # Use getboolean on the boolean config option
 
700
    server_settings["debug"] = server_config.getboolean\
 
701
                               (server_section, "debug")
 
702
    del server_config
 
703
    
 
704
    # Override the settings from the config file with command line
 
705
    # options, if set.
 
706
    for option in ("interface", "address", "port", "debug",
 
707
                   "priority", "servicename", "configdir"):
 
708
        value = getattr(options, option)
 
709
        if value is not None:
 
710
            server_settings[option] = value
 
711
    del options
 
712
    # Now we have our good server settings in "server_settings"
 
713
    
 
714
    # Parse config file with clients
 
715
    client_defaults = { "timeout": "1h",
 
716
                        "interval": "5m",
 
717
                        "checker": "fping -q -- %%(fqdn)s",
 
718
                        }
 
719
    client_config = ConfigParser.SafeConfigParser(client_defaults)
 
720
    client_config.read(os.path.join(server_settings["configdir"],
 
721
                                    "clients.conf"))
 
722
    
 
723
    global service
 
724
    service = AvahiService(name = server_settings["servicename"],
 
725
                           type = "_mandos._tcp", );
 
726
    if server_settings["interface"]:
 
727
        service.interface = if_nametoindex(server_settings["interface"])
671
728
    
672
729
    global main_loop
673
730
    global bus
681
738
            avahi.DBUS_INTERFACE_SERVER )
682
739
    # End of Avahi example code
683
740
    
684
 
    debug = options.debug
 
741
    debug = server_settings["debug"]
685
742
    
686
743
    if debug:
687
744
        console = logging.StreamHandler()
695
752
    def remove_from_clients(client):
696
753
        clients.remove(client)
697
754
        if not clients:
698
 
            logger.debug(u"No clients left, exiting")
699
 
            killme()
 
755
            logger.critical(u"No clients left, exiting")
 
756
            sys.exit()
700
757
    
701
 
    clients.update(Set(Client(name=section, options=options,
 
758
    clients.update(Set(Client(name = section,
702
759
                              stop_hook = remove_from_clients,
703
 
                              **(dict(client_config\
704
 
                                      .items(section))))
 
760
                              config
 
761
                              = dict(client_config.items(section)))
705
762
                       for section in client_config.sections()))
706
763
    
707
764
    if not debug:
725
782
    
726
783
    if not debug:
727
784
        signal.signal(signal.SIGINT, signal.SIG_IGN)
728
 
    signal.signal(signal.SIGHUP, lambda signum, frame: killme())
729
 
    signal.signal(signal.SIGTERM, lambda signum, frame: killme())
 
785
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
 
786
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
730
787
    
731
788
    for client in clients:
732
789
        client.start()
733
790
    
734
 
    tcp_server = IPv6_TCPServer((options.address, options.port),
 
791
    tcp_server = IPv6_TCPServer((server_settings["address"],
 
792
                                 server_settings["port"]),
735
793
                                tcp_handler,
736
 
                                options=options,
 
794
                                settings=server_settings,
737
795
                                clients=clients)
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:
 
796
    # Find out what port we got
 
797
    service.port = tcp_server.socket.getsockname()[1]
 
798
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
 
799
                u" scope_id %d" % tcp_server.socket.getsockname())
 
800
    
 
801
    #service.interface = tcp_server.socket.getsockname()[3]
 
802
    
 
803
    try:
 
804
        # From the Avahi example code
 
805
        server.connect_to_signal("StateChanged", server_state_changed)
 
806
        try:
 
807
            server_state_changed(server.GetState())
 
808
        except dbus.exceptions.DBusException, error:
 
809
            logger.critical(u"DBusException: %s", error)
 
810
            sys.exit(1)
 
811
        # End of Avahi example code
 
812
        
 
813
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
 
814
                             lambda *args, **kwargs:
 
815
                             tcp_server.handle_request\
 
816
                             (*args[2:], **kwargs) or True)
 
817
        
761
818
        logger.debug("Starting main loop")
762
819
        main_loop_started = True
763
820
        main_loop.run()
 
821
    except AvahiError, error:
 
822
        logger.critical(u"AvahiError: %s" + unicode(error))
 
823
        sys.exit(1)
764
824
    except KeyboardInterrupt:
765
825
        if debug:
766
826
            print
767
 
    
768
 
    sys.exit(exitstatus)
769
827
 
770
828
if __name__ == '__main__':
771
829
    main()