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  • Committer: Teddy Hogeborn
  • Date: 2008-07-21 01:50:31 UTC
  • Revision ID: teddy@fukt.bsnet.se-20080721015031-ivjiclli2j06hwgs
* Makefile: Include targets for all binaries.

* plugins.d/Makefile: Do nothing but call the parent Makefile.

* server.py: Added copyright statement and information.
  (Client.__init__): Added doc string.
  (Client.stop): Bug fix: Only log message if stopping for the first
                 time.  Check if the "stop_initiator_tag" and
                 "checker_initiator_tag" attributes exist before using
                 them.
  (Client.__del__): Call self.stop() instead of doing things here.
  (Client.checker_callback): Set self.checker_callback_tag and
                             self.checker to None unconditionally and
                             immediately.
  (Client.stop_checker): Added some checks to handle multiple calls.
  (tcp_handler.handle): Use "self.server.clients" instead of "clients".
  (__main__): Moved all code to the "main" function.
  (main): New.  New option "--address".  Instantiate IPv6_TCPServer
          with "options.address".  Log before starting main loop.
  (main.cleanup) Use "clients.pop()" to remove clients from the set as
                 they are stopped.

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server.py
6
6
# 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
 
# 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
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 <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
 
                # We don't need to redirect stdout and stderr, since
341
 
                # in normal mode, that is already done by daemon(),
342
 
                # and in debug mode we don't want to.  (Stdin is
343
 
                # always replaced by /dev/null.)
344
 
                self.checker = subprocess.Popen(command,
345
 
                                                close_fds=True,
346
 
                                                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="/")
347
282
                self.checker_callback_tag = gobject.child_watch_add\
348
283
                                            (self.checker.pid,
349
284
                                             self.checker_callback)
350
 
            except OSError, error:
 
285
            except subprocess.OSError, error:
351
286
                logger.error(u"Failed to start subprocess: %s",
352
287
                             error)
353
288
        # Re-run this periodically if run by gobject.timeout_add
357
292
        if self.checker_callback_tag:
358
293
            gobject.source_remove(self.checker_callback_tag)
359
294
            self.checker_callback_tag = None
360
 
        if getattr(self, "checker", None) is None:
 
295
        if not hasattr(self, "checker") or self.checker is None:
361
296
            return
362
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
 
297
        logger.debug("Stopping checker for %(name)s", vars(self))
363
298
        try:
364
299
            os.kill(self.checker.pid, signal.SIGTERM)
365
300
            #os.sleep(0.5)
366
301
            #if self.checker.poll() is None:
367
302
            #    os.kill(self.checker.pid, signal.SIGKILL)
368
303
        except OSError, error:
369
 
            if error.errno != errno.ESRCH: # No such process
 
304
            if error.errno != errno.ESRCH:
370
305
                raise
371
306
        self.checker = None
372
 
    def still_valid(self):
 
307
    def still_valid(self, now=None):
373
308
        """Has the timeout not yet passed for this client?"""
374
 
        now = datetime.datetime.now()
375
 
        if self.last_checked_ok is None:
 
309
        if now is None:
 
310
            now = datetime.datetime.now()
 
311
        if self.last_seen is None:
376
312
            return now < (self.created + self.timeout)
377
313
        else:
378
 
            return now < (self.last_checked_ok + self.timeout)
 
314
            return now < (self.last_seen + self.timeout)
379
315
 
380
316
 
381
317
def peer_certificate(session):
397
333
 
398
334
def fingerprint(openpgp):
399
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))
400
340
    # New GnuTLS "datum" with the OpenPGP public key
401
341
    datum = gnutls.library.types.gnutls_datum_t\
402
342
        (ctypes.cast(ctypes.c_char_p(openpgp),
403
343
                     ctypes.POINTER(ctypes.c_ubyte)),
404
344
         ctypes.c_uint(len(openpgp)))
405
 
    # New empty GnuTLS certificate
406
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
407
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
408
 
        (ctypes.byref(crt))
409
345
    # Import the OpenPGP public key into the certificate
410
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
411
 
                    (crt, ctypes.byref(datum),
412
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
413
 
    # Verify the self signature in the key
414
 
    crtverify = ctypes.c_uint();
415
 
    gnutls.library.functions.gnutls_openpgp_crt_verify_self\
416
 
        (crt, ctypes.c_uint(0), ctypes.byref(crtverify))
417
 
    if crtverify.value != 0:
418
 
        tmp = open("/tmp/tmp.gpg", "w")
419
 
        tmp.write(openpgp)
420
 
        tmp.close()
421
 
        gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
422
 
        raise gnutls.errors.CertificateSecurityError("Verify failed")
 
346
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
 
347
        (crt,
 
348
         ctypes.byref(datum),
 
349
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
423
350
    # New buffer for the fingerprint
424
351
    buffer = ctypes.create_string_buffer(20)
425
352
    buffer_length = ctypes.c_size_t()
441
368
    Note: This will run in its own forked process."""
442
369
    
443
370
    def handle(self):
444
 
        logger.info(u"TCP connection from: %s",
 
371
        logger.debug(u"TCP connection from: %s",
445
372
                     unicode(self.client_address))
446
 
        session = gnutls.connection.ClientSession\
447
 
                  (self.request, gnutls.connection.X509Credentials())
448
 
        
449
 
        line = self.request.makefile().readline()
450
 
        logger.debug(u"Protocol version: %r", line)
451
 
        try:
452
 
            if int(line.strip().split()[0]) > 1:
453
 
                raise RuntimeError
454
 
        except (ValueError, IndexError, RuntimeError), error:
455
 
            logger.error(u"Unknown protocol version: %s", error)
456
 
            return
457
 
        
458
 
        # Note: gnutls.connection.X509Credentials is really a generic
459
 
        # GnuTLS certificate credentials object so long as no X.509
460
 
        # keys are added to it.  Therefore, we can use it here despite
461
 
        # using OpenPGP certificates.
 
373
        session = gnutls.connection.ClientSession(self.request,
 
374
                                                  gnutls.connection.\
 
375
                                                  X509Credentials())
462
376
        
463
377
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
464
378
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
465
379
        #                "+DHE-DSS"))
466
 
        priority = "NORMAL"             # Fallback default, since this
467
 
                                        # MUST be set.
468
 
        if self.server.settings["priority"]:
469
 
            priority = self.server.settings["priority"]
 
380
        priority = "SECURE256"
 
381
        
470
382
        gnutls.library.functions.gnutls_priority_set_direct\
471
383
            (session._c_object, priority, None);
472
384
        
473
385
        try:
474
386
            session.handshake()
475
387
        except gnutls.errors.GNUTLSError, error:
476
 
            logger.warning(u"Handshake failed: %s", error)
 
388
            logger.debug(u"Handshake failed: %s", error)
477
389
            # Do not run session.bye() here: the session is not
478
390
            # established.  Just abandon the request.
479
391
            return
480
392
        try:
481
393
            fpr = fingerprint(peer_certificate(session))
482
394
        except (TypeError, gnutls.errors.GNUTLSError), error:
483
 
            logger.warning(u"Bad certificate: %s", error)
 
395
            logger.debug(u"Bad certificate: %s", error)
484
396
            session.bye()
485
397
            return
486
398
        logger.debug(u"Fingerprint: %s", fpr)
489
401
            if c.fingerprint == fpr:
490
402
                client = c
491
403
                break
492
 
        if not client:
493
 
            logger.warning(u"Client not found for fingerprint: %s",
494
 
                           fpr)
495
 
            session.bye()
496
 
            return
497
404
        # Have to check if client.still_valid(), since it is possible
498
405
        # that the client timed out while establishing the GnuTLS
499
406
        # session.
500
 
        if not client.still_valid():
501
 
            logger.warning(u"Client %(name)s is invalid",
502
 
                           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)
503
414
            session.bye()
504
415
            return
505
416
        sent_size = 0
515
426
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
516
427
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
517
428
    Attributes:
518
 
        settings:       Server settings
 
429
        options:        Command line options
519
430
        clients:        Set() of Client objects
520
431
    """
521
432
    address_family = socket.AF_INET6
522
433
    def __init__(self, *args, **kwargs):
523
 
        if "settings" in kwargs:
524
 
            self.settings = kwargs["settings"]
525
 
            del kwargs["settings"]
 
434
        if "options" in kwargs:
 
435
            self.options = kwargs["options"]
 
436
            del kwargs["options"]
526
437
        if "clients" in kwargs:
527
438
            self.clients = kwargs["clients"]
528
439
            del kwargs["clients"]
531
442
        """This overrides the normal server_bind() function
532
443
        to bind to an interface if one was specified, and also NOT to
533
444
        bind to an address or port if they were not specified."""
534
 
        if self.settings["interface"]:
535
 
            # 25 is from /usr/include/asm-i486/socket.h
536
 
            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
537
449
            try:
538
450
                self.socket.setsockopt(socket.SOL_SOCKET,
539
 
                                       SO_BINDTODEVICE,
540
 
                                       self.settings["interface"])
 
451
                                       socket.SO_BINDTODEVICE,
 
452
                                       self.options.interface)
541
453
            except socket.error, error:
542
454
                if error[0] == errno.EPERM:
543
 
                    logger.error(u"No permission to"
544
 
                                 u" bind to interface %s",
545
 
                                 self.settings["interface"])
 
455
                    logger.warning(u"No permission to"
 
456
                                   u" bind to interface %s",
 
457
                                   self.options.interface)
546
458
                else:
547
459
                    raise error
548
460
        # Only bind(2) the socket if we really need to.
551
463
                in6addr_any = "::"
552
464
                self.server_address = (in6addr_any,
553
465
                                       self.server_address[1])
554
 
            elif not self.server_address[1]:
 
466
            elif self.server_address[1] is None:
555
467
                self.server_address = (self.server_address[0],
556
468
                                       0)
557
 
#                 if self.settings["interface"]:
558
 
#                     self.server_address = (self.server_address[0],
559
 
#                                            0, # port
560
 
#                                            0, # flowinfo
561
 
#                                            if_nametoindex
562
 
#                                            (self.settings
563
 
#                                             ["interface"]))
564
469
            return super(type(self), self).server_bind()
565
470
 
566
471
 
577
482
    datetime.timedelta(1)
578
483
    >>> string_to_delta(u'1w')
579
484
    datetime.timedelta(7)
580
 
    >>> string_to_delta('5m 30s')
581
 
    datetime.timedelta(0, 330)
582
485
    """
583
 
    timevalue = datetime.timedelta(0)
584
 
    for s in interval.split():
585
 
        try:
586
 
            suffix=unicode(s[-1])
587
 
            value=int(s[:-1])
588
 
            if suffix == u"d":
589
 
                delta = datetime.timedelta(value)
590
 
            elif suffix == u"s":
591
 
                delta = datetime.timedelta(0, value)
592
 
            elif suffix == u"m":
593
 
                delta = datetime.timedelta(0, 0, 0, 0, value)
594
 
            elif suffix == u"h":
595
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, value)
596
 
            elif suffix == u"w":
597
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
598
 
            else:
599
 
                raise ValueError
600
 
        except (ValueError, IndexError):
 
486
    try:
 
487
        suffix=unicode(interval[-1])
 
488
        value=int(interval[:-1])
 
489
        if suffix == u"d":
 
490
            delta = datetime.timedelta(value)
 
491
        elif suffix == u"s":
 
492
            delta = datetime.timedelta(0, value)
 
493
        elif suffix == u"m":
 
494
            delta = datetime.timedelta(0, 0, 0, 0, value)
 
495
        elif suffix == u"h":
 
496
            delta = datetime.timedelta(0, 0, 0, 0, 0, value)
 
497
        elif suffix == u"w":
 
498
            delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
 
499
        else:
601
500
            raise ValueError
602
 
        timevalue += delta
603
 
    return timevalue
 
501
    except (ValueError, IndexError):
 
502
        raise ValueError
 
503
    return delta
 
504
 
 
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()
604
537
 
605
538
 
606
539
def server_state_changed(state):
607
540
    """Derived from the Avahi example code"""
608
541
    if state == avahi.SERVER_COLLISION:
609
 
        logger.error(u"Server name collision")
610
 
        service.remove()
 
542
        logger.warning(u"Server name collision")
 
543
        remove_service()
611
544
    elif state == avahi.SERVER_RUNNING:
612
 
        service.add()
 
545
        add_service()
613
546
 
614
547
 
615
548
def entry_group_state_changed(state, error):
616
549
    """Derived from the Avahi example code"""
 
550
    global serviceName, server, rename_count
 
551
    
617
552
    logger.debug(u"state change: %i", state)
618
553
    
619
554
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
620
555
        logger.debug(u"Service established.")
621
556
    elif state == avahi.ENTRY_GROUP_COLLISION:
622
 
        logger.warning(u"Service name collision.")
623
 
        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)
624
570
    elif state == avahi.ENTRY_GROUP_FAILURE:
625
 
        logger.critical(u"Error in group state changed %s",
626
 
                        unicode(error))
627
 
        raise AvahiGroupError("State changed: %s", str(error))
 
571
        logger.error(u"Error in group state changed %s",
 
572
                     unicode(error))
 
573
        killme(1)
 
574
 
628
575
 
629
576
def if_nametoindex(interface):
630
 
    """Call the C function if_nametoindex(), or equivalent"""
631
 
    global if_nametoindex
 
577
    """Call the C function if_nametoindex()"""
632
578
    try:
633
 
        if "ctypes.util" not in sys.modules:
634
 
            import ctypes.util
635
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
636
 
            (ctypes.util.find_library("c")).if_nametoindex
 
579
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
 
580
        return libc.if_nametoindex(interface)
637
581
    except (OSError, AttributeError):
638
582
        if "struct" not in sys.modules:
639
583
            import struct
640
584
        if "fcntl" not in sys.modules:
641
585
            import fcntl
642
 
        def if_nametoindex(interface):
643
 
            "Get an interface index the hard way, i.e. using fcntl()"
644
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
645
 
            s = socket.socket()
646
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
647
 
                                struct.pack("16s16x", interface))
648
 
            s.close()
649
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
650
 
            return interface_index
651
 
    return if_nametoindex(interface)
652
 
 
653
 
 
654
 
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):
655
596
    """See daemon(3).  Standard BSD Unix function.
656
597
    This should really exist as os.daemon, but it doesn't (yet)."""
657
598
    if os.fork():
659
600
    os.setsid()
660
601
    if not nochdir:
661
602
        os.chdir("/")
662
 
    if os.fork():
663
 
        sys.exit()
664
603
    if not noclose:
665
604
        # Close all standard open file descriptors
666
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
 
605
        null = os.open("/dev/null", os.O_NOCTTY | os.O_RDWR)
667
606
        if not stat.S_ISCHR(os.fstat(null).st_mode):
668
607
            raise OSError(errno.ENODEV,
669
608
                          "/dev/null not a character device")
674
613
            os.close(null)
675
614
 
676
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
 
677
625
def main():
 
626
    global exitstatus
 
627
    exitstatus = 0
678
628
    global main_loop_started
679
629
    main_loop_started = False
680
630
    
681
 
    parser = OptionParser(version = "%%prog %s" % version)
 
631
    parser = OptionParser()
682
632
    parser.add_option("-i", "--interface", type="string",
683
 
                      metavar="IF", help="Bind to interface IF")
684
 
    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,
685
636
                      help="Address to listen for requests on")
686
 
    parser.add_option("-p", "--port", type="int",
 
637
    parser.add_option("-p", "--port", type="int", default=None,
687
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")
688
645
    parser.add_option("--check", action="store_true", default=False,
689
646
                      help="Run self-test")
690
 
    parser.add_option("--debug", action="store_true",
691
 
                      help="Debug mode; run in foreground and log to"
692
 
                      " terminal")
693
 
    parser.add_option("--priority", type="string", help="GnuTLS"
694
 
                      " priority string (see GnuTLS documentation)")
695
 
    parser.add_option("--servicename", type="string", metavar="NAME",
696
 
                      help="Zeroconf service name")
697
 
    parser.add_option("--configdir", type="string",
698
 
                      default="/etc/mandos", metavar="DIR",
699
 
                      help="Directory to search for configuration"
700
 
                      " files")
 
647
    parser.add_option("--debug", action="store_true", default=False,
 
648
                      help="Debug mode")
701
649
    (options, args) = parser.parse_args()
702
650
    
703
651
    if options.check:
705
653
        doctest.testmod()
706
654
        sys.exit()
707
655
    
708
 
    # Default values for config file for server-global settings
709
 
    server_defaults = { "interface": "",
710
 
                        "address": "",
711
 
                        "port": "",
712
 
                        "debug": "False",
713
 
                        "priority":
714
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
715
 
                        "servicename": "Mandos",
716
 
                        }
717
 
    
718
 
    # Parse config file for server-global settings
719
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
720
 
    del server_defaults
721
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
722
 
    # Convert the SafeConfigParser object to a dict
723
 
    server_settings = server_config.defaults()
724
 
    # Use getboolean on the boolean config option
725
 
    server_settings["debug"] = server_config.getboolean\
726
 
                               ("DEFAULT", "debug")
727
 
    del server_config
728
 
    
729
 
    # Override the settings from the config file with command line
730
 
    # options, if set.
731
 
    for option in ("interface", "address", "port", "debug",
732
 
                   "priority", "servicename", "configdir"):
733
 
        value = getattr(options, option)
734
 
        if value is not None:
735
 
            server_settings[option] = value
736
 
    del options
737
 
    # Now we have our good server settings in "server_settings"
738
 
    
739
 
    debug = server_settings["debug"]
740
 
    
741
 
    if not debug:
742
 
        syslogger.setLevel(logging.WARNING)
743
 
        console.setLevel(logging.WARNING)
744
 
    
745
 
    if server_settings["servicename"] != "Mandos":
746
 
        syslogger.setFormatter(logging.Formatter\
747
 
                               ('Mandos (%s): %%(levelname)s:'
748
 
                                ' %%(message)s'
749
 
                                % server_settings["servicename"]))
750
 
    
751
 
    # Parse config file with clients
752
 
    client_defaults = { "timeout": "1h",
753
 
                        "interval": "5m",
754
 
                        "checker": "fping -q -- %(host)s",
755
 
                        "host": "",
756
 
                        }
757
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
758
 
    client_config.read(os.path.join(server_settings["configdir"],
759
 
                                    "clients.conf"))
760
 
    
761
 
    global service
762
 
    service = AvahiService(name = server_settings["servicename"],
763
 
                           type = "_mandos._tcp", );
764
 
    if server_settings["interface"]:
765
 
        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")
766
671
    
767
672
    global main_loop
768
673
    global bus
776
681
            avahi.DBUS_INTERFACE_SERVER )
777
682
    # End of Avahi example code
778
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
    
779
694
    clients = Set()
780
695
    def remove_from_clients(client):
781
696
        clients.remove(client)
782
697
        if not clients:
783
 
            logger.critical(u"No clients left, exiting")
784
 
            sys.exit()
 
698
            logger.debug(u"No clients left, exiting")
 
699
            killme()
785
700
    
786
 
    clients.update(Set(Client(name = section,
 
701
    clients.update(Set(Client(name=section, options=options,
787
702
                              stop_hook = remove_from_clients,
788
 
                              config
789
 
                              = dict(client_config.items(section)))
 
703
                              **(dict(client_config\
 
704
                                      .items(section))))
790
705
                       for section in client_config.sections()))
791
 
    if not clients:
792
 
        logger.critical(u"No clients defined")
793
 
        sys.exit(1)
794
 
    
795
 
    if debug:
796
 
        # Redirect stdin so all checkers get /dev/null
797
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
798
 
        os.dup2(null, sys.stdin.fileno())
799
 
        if null > 2:
800
 
            os.close(null)
801
 
    else:
802
 
        # No console logging
803
 
        logger.removeHandler(console)
804
 
        # Close all input and output, do double fork, etc.
805
 
        daemon()
806
 
    
807
 
    pidfilename = "/var/run/mandos/mandos.pid"
808
 
    pid = os.getpid()
809
 
    try:
810
 
        pidfile = open(pidfilename, "w")
811
 
        pidfile.write(str(pid) + "\n")
812
 
        pidfile.close()
813
 
        del pidfile
814
 
    except IOError, err:
815
 
        logger.error(u"Could not write %s file with PID %d",
816
 
                     pidfilename, os.getpid())
 
706
    
 
707
    if not debug:
 
708
        daemon(False, False)
817
709
    
818
710
    def cleanup():
819
711
        "Cleanup function; run on exit"
833
725
    
834
726
    if not debug:
835
727
        signal.signal(signal.SIGINT, signal.SIG_IGN)
836
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
837
 
    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())
838
730
    
839
731
    for client in clients:
840
732
        client.start()
841
733
    
842
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
843
 
                                 server_settings["port"]),
 
734
    tcp_server = IPv6_TCPServer((options.address, options.port),
844
735
                                tcp_handler,
845
 
                                settings=server_settings,
 
736
                                options=options,
846
737
                                clients=clients)
847
 
    # Find out what port we got
848
 
    service.port = tcp_server.socket.getsockname()[1]
849
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
850
 
                u" scope_id %d" % tcp_server.socket.getsockname())
851
 
    
852
 
    #service.interface = tcp_server.socket.getsockname()[3]
853
 
    
854
 
    try:
855
 
        # From the Avahi example code
856
 
        server.connect_to_signal("StateChanged", server_state_changed)
857
 
        try:
858
 
            server_state_changed(server.GetState())
859
 
        except dbus.exceptions.DBusException, error:
860
 
            logger.critical(u"DBusException: %s", error)
861
 
            sys.exit(1)
862
 
        # End of Avahi example code
863
 
        
864
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
865
 
                             lambda *args, **kwargs:
866
 
                             tcp_server.handle_request\
867
 
                             (*args[2:], **kwargs) or True)
868
 
        
869
 
        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")
870
762
        main_loop_started = True
871
763
        main_loop.run()
872
 
    except AvahiError, error:
873
 
        logger.critical(u"AvahiError: %s" + unicode(error))
874
 
        sys.exit(1)
875
764
    except KeyboardInterrupt:
876
765
        if debug:
877
766
            print
 
767
    
 
768
    sys.exit(exitstatus)
878
769
 
879
770
if __name__ == '__main__':
880
771
    main()