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  • Committer: Teddy Hogeborn
  • Date: 2008-07-22 06:25:35 UTC
  • mfrom: (24.1.2 mandos)
  • Revision ID: teddy@fukt.bsnet.se-20080722062535-whz5do0b3dzw6m08
Merge.

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# This program is partly derived from an example program for an Avahi
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# service publisher, downloaded from
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# <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
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# 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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# This program is free software: you can redistribute it and/or modify
17
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# it under the terms of the GNU General Public License as published by
24
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#     GNU General Public License for more details.
25
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# You should have received a copy of the GNU General Public License
27
 
# along with this program.  If not, see
28
 
# <http://www.gnu.org/licenses/>.
 
27
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
29
28
30
 
# 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/>.
31
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33
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from __future__ import division
55
55
import stat
56
56
import logging
57
57
import logging.handlers
58
 
import pwd
59
58
 
60
59
import dbus
61
60
import gobject
63
62
from dbus.mainloop.glib import DBusGMainLoop
64
63
import ctypes
65
64
 
66
 
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
 
67
76
 
68
77
logger = logging.Logger('mandos')
69
78
syslogger = logging.handlers.SysLogHandler\
70
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
71
 
             address = "/dev/log")
 
79
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON)
72
80
syslogger.setFormatter(logging.Formatter\
73
 
                        ('Mandos: %(levelname)s: %(message)s'))
 
81
                        ('%(levelname)s: %(message)s'))
74
82
logger.addHandler(syslogger)
75
 
 
76
 
console = logging.StreamHandler()
77
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
78
 
                                       ' %(message)s'))
79
 
logger.addHandler(console)
80
 
 
81
 
class AvahiError(Exception):
82
 
    def __init__(self, value):
83
 
        self.value = value
84
 
    def __str__(self):
85
 
        return repr(self.value)
86
 
 
87
 
class AvahiServiceError(AvahiError):
88
 
    pass
89
 
 
90
 
class AvahiGroupError(AvahiError):
91
 
    pass
92
 
 
93
 
 
94
 
class AvahiService(object):
95
 
    """An Avahi (Zeroconf) service.
96
 
    Attributes:
97
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
98
 
               Used to optionally bind to the specified interface.
99
 
    name: string; Example: 'Mandos'
100
 
    type: string; Example: '_mandos._tcp'.
101
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
102
 
    port: integer; what port to announce
103
 
    TXT: list of strings; TXT record for the service
104
 
    domain: string; Domain to publish on, default to .local if empty.
105
 
    host: string; Host to publish records for, default is localhost
106
 
    max_renames: integer; maximum number of renames
107
 
    rename_count: integer; counter so we only rename after collisions
108
 
                  a sensible number of times
109
 
    """
110
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
111
 
                 type = None, port = None, TXT = None, domain = "",
112
 
                 host = "", max_renames = 32768):
113
 
        self.interface = interface
114
 
        self.name = name
115
 
        self.type = type
116
 
        self.port = port
117
 
        if TXT is None:
118
 
            self.TXT = []
119
 
        else:
120
 
            self.TXT = TXT
121
 
        self.domain = domain
122
 
        self.host = host
123
 
        self.rename_count = 0
124
 
        self.max_renames = max_renames
125
 
    def rename(self):
126
 
        """Derived from the Avahi example code"""
127
 
        if self.rename_count >= self.max_renames:
128
 
            logger.critical(u"No suitable Zeroconf service name found"
129
 
                            u" after %i retries, exiting.",
130
 
                            rename_count)
131
 
            raise AvahiServiceError("Too many renames")
132
 
        self.name = server.GetAlternativeServiceName(self.name)
133
 
        logger.info(u"Changing Zeroconf service name to %r ...",
134
 
                    str(self.name))
135
 
        syslogger.setFormatter(logging.Formatter\
136
 
                               ('Mandos (%s): %%(levelname)s:'
137
 
                               ' %%(message)s' % self.name))
138
 
        self.remove()
139
 
        self.add()
140
 
        self.rename_count += 1
141
 
    def remove(self):
142
 
        """Derived from the Avahi example code"""
143
 
        if group is not None:
144
 
            group.Reset()
145
 
    def add(self):
146
 
        """Derived from the Avahi example code"""
147
 
        global group
148
 
        if group is None:
149
 
            group = dbus.Interface\
150
 
                    (bus.get_object(avahi.DBUS_NAME,
151
 
                                    server.EntryGroupNew()),
152
 
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
153
 
            group.connect_to_signal('StateChanged',
154
 
                                    entry_group_state_changed)
155
 
        logger.debug(u"Adding Zeroconf service '%s' of type '%s' ...",
156
 
                     service.name, service.type)
157
 
        group.AddService(
158
 
                self.interface,         # interface
159
 
                avahi.PROTO_INET6,      # protocol
160
 
                dbus.UInt32(0),         # flags
161
 
                self.name, self.type,
162
 
                self.domain, self.host,
163
 
                dbus.UInt16(self.port),
164
 
                avahi.string_array_to_txt_array(self.TXT))
165
 
        group.Commit()
166
 
 
 
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
167
89
# From the Avahi example code:
168
 
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
169
99
# End of Avahi example code
170
100
 
171
101
 
176
106
    fingerprint: string (40 or 32 hexadecimal digits); used to
177
107
                 uniquely identify the client
178
108
    secret:    bytestring; sent verbatim (over TLS) to client
179
 
    host:      string; available for use by the checker command
180
 
    created:   datetime.datetime(); object creation, not client host
181
 
    last_checked_ok: datetime.datetime() or None if not yet checked OK
182
 
    timeout:   datetime.timedelta(); How long from last_checked_ok
183
 
                                     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
184
114
    interval:  datetime.timedelta(); How often to start a new checker
185
115
    stop_hook: If set, called by stop() as stop_hook(self)
186
116
    checker:   subprocess.Popen(); a running checker process used
187
117
                                   to see if the client lives.
188
 
                                   'None' if no process is running.
 
118
                                   Is None if no process is running.
189
119
    checker_initiator_tag: a gobject event source tag, or None
190
120
    stop_initiator_tag:    - '' -
191
121
    checker_callback_tag:  - '' -
192
122
    checker_command: string; External command which is run to check if
193
 
                     client lives.  %() expansions are done at
 
123
                     client lives.  %()s expansions are done at
194
124
                     runtime with vars(self) as dict, so that for
195
125
                     instance %(name)s can be used in the command.
196
126
    Private attibutes:
197
127
    _timeout: Real variable for 'timeout'
198
128
    _interval: Real variable for 'interval'
199
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
 
129
    _timeout_milliseconds: Used by gobject.timeout_add()
200
130
    _interval_milliseconds: - '' -
201
131
    """
202
132
    def _set_timeout(self, timeout):
222
152
    interval = property(lambda self: self._interval,
223
153
                        _set_interval)
224
154
    del _set_interval
225
 
    def __init__(self, name = None, stop_hook=None, config={}):
226
 
        """Note: the 'checker' key in 'config' sets the
227
 
        'checker_command' attribute and *not* the 'checker'
228
 
        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.."""
229
160
        self.name = name
230
161
        logger.debug(u"Creating client %r", self.name)
231
 
        # Uppercase and remove spaces from fingerprint for later
232
 
        # comparison purposes with return value from the fingerprint()
233
 
        # function
234
 
        self.fingerprint = config["fingerprint"].upper()\
235
 
                           .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"")
236
166
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
237
 
        if "secret" in config:
238
 
            self.secret = config["secret"].decode(u"base64")
239
 
        elif "secfile" in config:
240
 
            sf = open(config["secfile"])
 
167
        if secret:
 
168
            self.secret = secret.decode(u"base64")
 
169
        elif secfile:
 
170
            sf = open(secfile)
241
171
            self.secret = sf.read()
242
172
            sf.close()
243
173
        else:
244
 
            raise TypeError(u"No secret or secfile for client %s"
245
 
                            % self.name)
246
 
        self.host = config.get("host", "")
 
174
            raise RuntimeError(u"No secret or secfile for client %s"
 
175
                               % self.name)
 
176
        self.fqdn = fqdn                # string
247
177
        self.created = datetime.datetime.now()
248
 
        self.last_checked_ok = None
249
 
        self.timeout = string_to_delta(config["timeout"])
250
 
        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)
251
181
        self.stop_hook = stop_hook
252
182
        self.checker = None
253
183
        self.checker_initiator_tag = None
254
184
        self.stop_initiator_tag = None
255
185
        self.checker_callback_tag = None
256
 
        self.check_command = config["checker"]
 
186
        self.check_command = checker
257
187
    def start(self):
258
188
        """Start this client's checker and timeout hooks"""
259
189
        # Schedule a new checker to be started an 'interval' from now,
269
199
                                   self.stop)
270
200
    def stop(self):
271
201
        """Stop this client.
272
 
        The possibility that a client might be restarted is left open,
273
 
        but not currently used."""
 
202
        The possibility that this client might be restarted is left
 
203
        open, but not currently used."""
274
204
        # If this client doesn't have a secret, it is already stopped.
275
 
        if hasattr(self, "secret") and self.secret:
276
 
            logger.info(u"Stopping client %s", self.name)
 
205
        if self.secret:
 
206
            logger.debug(u"Stopping client %s", self.name)
277
207
            self.secret = None
278
208
        else:
279
209
            return False
280
 
        if getattr(self, "stop_initiator_tag", False):
 
210
        if hasattr(self, "stop_initiator_tag") \
 
211
               and self.stop_initiator_tag:
281
212
            gobject.source_remove(self.stop_initiator_tag)
282
213
            self.stop_initiator_tag = None
283
 
        if getattr(self, "checker_initiator_tag", False):
 
214
        if hasattr(self, "checker_initiator_tag") \
 
215
               and self.checker_initiator_tag:
284
216
            gobject.source_remove(self.checker_initiator_tag)
285
217
            self.checker_initiator_tag = None
286
218
        self.stop_checker()
298
230
        self.checker = None
299
231
        if os.WIFEXITED(condition) \
300
232
               and (os.WEXITSTATUS(condition) == 0):
301
 
            logger.info(u"Checker for %(name)s succeeded",
302
 
                        vars(self))
303
 
            self.last_checked_ok = now
 
233
            logger.debug(u"Checker for %(name)s succeeded",
 
234
                         vars(self))
 
235
            self.last_seen = now
304
236
            gobject.source_remove(self.stop_initiator_tag)
305
237
            self.stop_initiator_tag = gobject.timeout_add\
306
238
                                      (self._timeout_milliseconds,
309
241
            logger.warning(u"Checker for %(name)s crashed?",
310
242
                           vars(self))
311
243
        else:
312
 
            logger.info(u"Checker for %(name)s failed",
313
 
                        vars(self))
 
244
            logger.debug(u"Checker for %(name)s failed",
 
245
                         vars(self))
314
246
    def start_checker(self):
315
247
        """Start a new checker subprocess if one is not running.
316
248
        If a checker already exists, leave it running and do
325
257
        # is as it should be.
326
258
        if self.checker is None:
327
259
            try:
328
 
                # In case check_command has exactly one % operator
329
 
                command = self.check_command % self.host
 
260
                command = self.check_command % self.fqdn
330
261
            except TypeError:
331
 
                # Escape attributes for the shell
332
262
                escaped_attrs = dict((key, re.escape(str(val)))
333
263
                                     for key, val in
334
264
                                     vars(self).iteritems())
335
265
                try:
336
266
                    command = self.check_command % escaped_attrs
337
267
                except TypeError, error:
338
 
                    logger.error(u'Could not format string "%s":'
339
 
                                 u' %s', self.check_command, error)
 
268
                    logger.critical(u'Could not format string "%s":'
 
269
                                    u' %s', self.check_command, error)
340
270
                    return True # Try again later
341
271
            try:
342
 
                logger.info(u"Starting checker %r for %s",
343
 
                            command, self.name)
344
 
                # We don't need to redirect stdout and stderr, since
345
 
                # in normal mode, that is already done by daemon(),
346
 
                # and in debug mode we don't want to.  (Stdin is
347
 
                # always replaced by /dev/null.)
348
 
                self.checker = subprocess.Popen(command,
349
 
                                                close_fds=True,
350
 
                                                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="/")
351
278
                self.checker_callback_tag = gobject.child_watch_add\
352
279
                                            (self.checker.pid,
353
280
                                             self.checker_callback)
354
 
            except OSError, error:
 
281
            except subprocess.OSError, error:
355
282
                logger.error(u"Failed to start subprocess: %s",
356
283
                             error)
357
284
        # Re-run this periodically if run by gobject.timeout_add
361
288
        if self.checker_callback_tag:
362
289
            gobject.source_remove(self.checker_callback_tag)
363
290
            self.checker_callback_tag = None
364
 
        if getattr(self, "checker", None) is None:
 
291
        if not hasattr(self, "checker") or self.checker is None:
365
292
            return
366
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
 
293
        logger.debug("Stopping checker for %(name)s", vars(self))
367
294
        try:
368
295
            os.kill(self.checker.pid, signal.SIGTERM)
369
296
            #os.sleep(0.5)
370
297
            #if self.checker.poll() is None:
371
298
            #    os.kill(self.checker.pid, signal.SIGKILL)
372
299
        except OSError, error:
373
 
            if error.errno != errno.ESRCH: # No such process
 
300
            if error.errno != errno.ESRCH:
374
301
                raise
375
302
        self.checker = None
376
 
    def still_valid(self):
 
303
    def still_valid(self, now=None):
377
304
        """Has the timeout not yet passed for this client?"""
378
 
        now = datetime.datetime.now()
379
 
        if self.last_checked_ok is None:
 
305
        if now is None:
 
306
            now = datetime.datetime.now()
 
307
        if self.last_seen is None:
380
308
            return now < (self.created + self.timeout)
381
309
        else:
382
 
            return now < (self.last_checked_ok + self.timeout)
 
310
            return now < (self.last_seen + self.timeout)
383
311
 
384
312
 
385
313
def peer_certificate(session):
401
329
 
402
330
def fingerprint(openpgp):
403
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))
404
336
    # New GnuTLS "datum" with the OpenPGP public key
405
337
    datum = gnutls.library.types.gnutls_datum_t\
406
338
        (ctypes.cast(ctypes.c_char_p(openpgp),
407
339
                     ctypes.POINTER(ctypes.c_ubyte)),
408
340
         ctypes.c_uint(len(openpgp)))
409
 
    # New empty GnuTLS certificate
410
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
411
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
412
 
        (ctypes.byref(crt))
413
341
    # Import the OpenPGP public key into the certificate
414
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
415
 
                    (crt, ctypes.byref(datum),
416
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
417
 
    # Verify the self signature in the key
418
 
    crtverify = ctypes.c_uint();
419
 
    gnutls.library.functions.gnutls_openpgp_crt_verify_self\
420
 
        (crt, 0, ctypes.byref(crtverify))
421
 
    if crtverify.value != 0:
422
 
        gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
423
 
        raise gnutls.errors.CertificateSecurityError("Verify failed")
 
342
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
 
343
        (crt,
 
344
         ctypes.byref(datum),
 
345
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
424
346
    # New buffer for the fingerprint
425
347
    buffer = ctypes.create_string_buffer(20)
426
348
    buffer_length = ctypes.c_size_t()
442
364
    Note: This will run in its own forked process."""
443
365
    
444
366
    def handle(self):
445
 
        logger.info(u"TCP connection from: %s",
 
367
        logger.debug(u"TCP connection from: %s",
446
368
                     unicode(self.client_address))
447
 
        session = gnutls.connection.ClientSession\
448
 
                  (self.request, gnutls.connection.X509Credentials())
449
 
        
450
 
        line = self.request.makefile().readline()
451
 
        logger.debug(u"Protocol version: %r", line)
452
 
        try:
453
 
            if int(line.strip().split()[0]) > 1:
454
 
                raise RuntimeError
455
 
        except (ValueError, IndexError, RuntimeError), error:
456
 
            logger.error(u"Unknown protocol version: %s", error)
457
 
            return
458
 
        
459
 
        # Note: gnutls.connection.X509Credentials is really a generic
460
 
        # GnuTLS certificate credentials object so long as no X.509
461
 
        # keys are added to it.  Therefore, we can use it here despite
462
 
        # using OpenPGP certificates.
 
369
        session = gnutls.connection.ClientSession(self.request,
 
370
                                                  gnutls.connection.\
 
371
                                                  X509Credentials())
463
372
        
464
373
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
465
374
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
466
375
        #                "+DHE-DSS"))
467
 
        priority = "NORMAL"             # Fallback default, since this
468
 
                                        # MUST be set.
469
 
        if self.server.settings["priority"]:
470
 
            priority = self.server.settings["priority"]
 
376
        priority = "NORMAL"
 
377
        if self.server.options.priority:
 
378
            priority = self.server.options.priority
471
379
        gnutls.library.functions.gnutls_priority_set_direct\
472
380
            (session._c_object, priority, None);
473
381
        
474
382
        try:
475
383
            session.handshake()
476
384
        except gnutls.errors.GNUTLSError, error:
477
 
            logger.warning(u"Handshake failed: %s", error)
 
385
            logger.debug(u"Handshake failed: %s", error)
478
386
            # Do not run session.bye() here: the session is not
479
387
            # established.  Just abandon the request.
480
388
            return
481
389
        try:
482
390
            fpr = fingerprint(peer_certificate(session))
483
391
        except (TypeError, gnutls.errors.GNUTLSError), error:
484
 
            logger.warning(u"Bad certificate: %s", error)
 
392
            logger.debug(u"Bad certificate: %s", error)
485
393
            session.bye()
486
394
            return
487
395
        logger.debug(u"Fingerprint: %s", fpr)
490
398
            if c.fingerprint == fpr:
491
399
                client = c
492
400
                break
493
 
        if not client:
494
 
            logger.warning(u"Client not found for fingerprint: %s",
495
 
                           fpr)
496
 
            session.bye()
497
 
            return
498
401
        # Have to check if client.still_valid(), since it is possible
499
402
        # that the client timed out while establishing the GnuTLS
500
403
        # session.
501
 
        if not client.still_valid():
502
 
            logger.warning(u"Client %(name)s is invalid",
503
 
                           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)
504
411
            session.bye()
505
412
            return
506
413
        sent_size = 0
516
423
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
517
424
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
518
425
    Attributes:
519
 
        settings:       Server settings
 
426
        options:        Command line options
520
427
        clients:        Set() of Client objects
521
 
        enabled:        Boolean; whether this server is activated yet
522
428
    """
523
429
    address_family = socket.AF_INET6
524
430
    def __init__(self, *args, **kwargs):
525
 
        if "settings" in kwargs:
526
 
            self.settings = kwargs["settings"]
527
 
            del kwargs["settings"]
 
431
        if "options" in kwargs:
 
432
            self.options = kwargs["options"]
 
433
            del kwargs["options"]
528
434
        if "clients" in kwargs:
529
435
            self.clients = kwargs["clients"]
530
436
            del kwargs["clients"]
531
 
        self.enabled = False
532
437
        return super(type(self), self).__init__(*args, **kwargs)
533
438
    def server_bind(self):
534
439
        """This overrides the normal server_bind() function
535
440
        to bind to an interface if one was specified, and also NOT to
536
441
        bind to an address or port if they were not specified."""
537
 
        if self.settings["interface"]:
538
 
            # 25 is from /usr/include/asm-i486/socket.h
539
 
            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
540
446
            try:
541
447
                self.socket.setsockopt(socket.SOL_SOCKET,
542
 
                                       SO_BINDTODEVICE,
543
 
                                       self.settings["interface"])
 
448
                                       socket.SO_BINDTODEVICE,
 
449
                                       self.options.interface)
544
450
            except socket.error, error:
545
451
                if error[0] == errno.EPERM:
546
 
                    logger.error(u"No permission to"
547
 
                                 u" bind to interface %s",
548
 
                                 self.settings["interface"])
 
452
                    logger.warning(u"No permission to"
 
453
                                   u" bind to interface %s",
 
454
                                   self.options.interface)
549
455
                else:
550
456
                    raise error
551
457
        # Only bind(2) the socket if we really need to.
554
460
                in6addr_any = "::"
555
461
                self.server_address = (in6addr_any,
556
462
                                       self.server_address[1])
557
 
            elif not self.server_address[1]:
 
463
            elif self.server_address[1] is None:
558
464
                self.server_address = (self.server_address[0],
559
465
                                       0)
560
 
#                 if self.settings["interface"]:
561
 
#                     self.server_address = (self.server_address[0],
562
 
#                                            0, # port
563
 
#                                            0, # flowinfo
564
 
#                                            if_nametoindex
565
 
#                                            (self.settings
566
 
#                                             ["interface"]))
567
466
            return super(type(self), self).server_bind()
568
 
    def server_activate(self):
569
 
        if self.enabled:
570
 
            return super(type(self), self).server_activate()
571
 
    def enable(self):
572
 
        self.enabled = True
573
467
 
574
468
 
575
469
def string_to_delta(interval):
585
479
    datetime.timedelta(1)
586
480
    >>> string_to_delta(u'1w')
587
481
    datetime.timedelta(7)
588
 
    >>> string_to_delta('5m 30s')
589
 
    datetime.timedelta(0, 330)
590
482
    """
591
 
    timevalue = datetime.timedelta(0)
592
 
    for s in interval.split():
593
 
        try:
594
 
            suffix=unicode(s[-1])
595
 
            value=int(s[:-1])
596
 
            if suffix == u"d":
597
 
                delta = datetime.timedelta(value)
598
 
            elif suffix == u"s":
599
 
                delta = datetime.timedelta(0, value)
600
 
            elif suffix == u"m":
601
 
                delta = datetime.timedelta(0, 0, 0, 0, value)
602
 
            elif suffix == u"h":
603
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, value)
604
 
            elif suffix == u"w":
605
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
606
 
            else:
607
 
                raise ValueError
608
 
        except (ValueError, IndexError):
 
483
    try:
 
484
        suffix=unicode(interval[-1])
 
485
        value=int(interval[:-1])
 
486
        if suffix == u"d":
 
487
            delta = datetime.timedelta(value)
 
488
        elif suffix == u"s":
 
489
            delta = datetime.timedelta(0, value)
 
490
        elif suffix == u"m":
 
491
            delta = datetime.timedelta(0, 0, 0, 0, value)
 
492
        elif suffix == u"h":
 
493
            delta = datetime.timedelta(0, 0, 0, 0, 0, value)
 
494
        elif suffix == u"w":
 
495
            delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
 
496
        else:
609
497
            raise ValueError
610
 
        timevalue += delta
611
 
    return timevalue
 
498
    except (ValueError, IndexError):
 
499
        raise ValueError
 
500
    return delta
 
501
 
 
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()
612
534
 
613
535
 
614
536
def server_state_changed(state):
615
537
    """Derived from the Avahi example code"""
616
538
    if state == avahi.SERVER_COLLISION:
617
 
        logger.error(u"Zeroconf server name collision")
618
 
        service.remove()
 
539
        logger.warning(u"Server name collision")
 
540
        remove_service()
619
541
    elif state == avahi.SERVER_RUNNING:
620
 
        service.add()
 
542
        add_service()
621
543
 
622
544
 
623
545
def entry_group_state_changed(state, error):
624
546
    """Derived from the Avahi example code"""
625
 
    logger.debug(u"Avahi state change: %i", state)
 
547
    global serviceName, server, rename_count
 
548
    
 
549
    logger.debug(u"state change: %i", state)
626
550
    
627
551
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
628
 
        logger.debug(u"Zeroconf service established.")
 
552
        logger.debug(u"Service established.")
629
553
    elif state == avahi.ENTRY_GROUP_COLLISION:
630
 
        logger.warning(u"Zeroconf service name collision.")
631
 
        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)
632
567
    elif state == avahi.ENTRY_GROUP_FAILURE:
633
 
        logger.critical(u"Avahi: Error in group state changed %s",
634
 
                        unicode(error))
635
 
        raise AvahiGroupError("State changed: %s", str(error))
 
568
        logger.error(u"Error in group state changed %s",
 
569
                     unicode(error))
 
570
        killme(1)
 
571
 
636
572
 
637
573
def if_nametoindex(interface):
638
 
    """Call the C function if_nametoindex(), or equivalent"""
639
 
    global if_nametoindex
 
574
    """Call the C function if_nametoindex()"""
640
575
    try:
641
 
        if "ctypes.util" not in sys.modules:
642
 
            import ctypes.util
643
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
644
 
            (ctypes.util.find_library("c")).if_nametoindex
 
576
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
 
577
        return libc.if_nametoindex(interface)
645
578
    except (OSError, AttributeError):
646
579
        if "struct" not in sys.modules:
647
580
            import struct
648
581
        if "fcntl" not in sys.modules:
649
582
            import fcntl
650
 
        def if_nametoindex(interface):
651
 
            "Get an interface index the hard way, i.e. using fcntl()"
652
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
653
 
            s = socket.socket()
654
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
655
 
                                struct.pack("16s16x", interface))
656
 
            s.close()
657
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
658
 
            return interface_index
659
 
    return if_nametoindex(interface)
660
 
 
661
 
 
662
 
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):
663
593
    """See daemon(3).  Standard BSD Unix function.
664
594
    This should really exist as os.daemon, but it doesn't (yet)."""
665
595
    if os.fork():
667
597
    os.setsid()
668
598
    if not nochdir:
669
599
        os.chdir("/")
670
 
    if os.fork():
671
 
        sys.exit()
672
600
    if not noclose:
673
601
        # Close all standard open file descriptors
674
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
 
602
        null = os.open("/dev/null", os.O_NOCTTY | os.O_RDWR)
675
603
        if not stat.S_ISCHR(os.fstat(null).st_mode):
676
604
            raise OSError(errno.ENODEV,
677
605
                          "/dev/null not a character device")
682
610
            os.close(null)
683
611
 
684
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
 
685
622
def main():
 
623
    global exitstatus
 
624
    exitstatus = 0
686
625
    global main_loop_started
687
626
    main_loop_started = False
688
627
    
689
 
    parser = OptionParser(version = "%%prog %s" % version)
 
628
    parser = OptionParser()
690
629
    parser.add_option("-i", "--interface", type="string",
691
 
                      metavar="IF", help="Bind to interface IF")
692
 
    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,
693
633
                      help="Address to listen for requests on")
694
 
    parser.add_option("-p", "--port", type="int",
 
634
    parser.add_option("-p", "--port", type="int", default=None,
695
635
                      help="Port number to receive requests on")
696
636
    parser.add_option("--check", action="store_true", default=False,
697
637
                      help="Run self-test")
698
 
    parser.add_option("--debug", action="store_true",
699
 
                      help="Debug mode; run in foreground and log to"
700
 
                      " terminal")
701
 
    parser.add_option("--priority", type="string", help="GnuTLS"
702
 
                      " priority string (see GnuTLS documentation)")
703
 
    parser.add_option("--servicename", type="string", metavar="NAME",
704
 
                      help="Zeroconf service name")
705
 
    parser.add_option("--configdir", type="string",
706
 
                      default="/etc/mandos", metavar="DIR",
707
 
                      help="Directory to search for configuration"
708
 
                      " 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")
709
646
    (options, args) = parser.parse_args()
710
647
    
711
648
    if options.check:
713
650
        doctest.testmod()
714
651
        sys.exit()
715
652
    
716
 
    # Default values for config file for server-global settings
717
 
    server_defaults = { "interface": "",
718
 
                        "address": "",
719
 
                        "port": "",
720
 
                        "debug": "False",
721
 
                        "priority":
722
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
723
 
                        "servicename": "Mandos",
724
 
                        }
725
 
    
726
 
    # Parse config file for server-global settings
727
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
728
 
    del server_defaults
729
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
730
 
    # Convert the SafeConfigParser object to a dict
731
 
    server_settings = server_config.defaults()
732
 
    # Use getboolean on the boolean config option
733
 
    server_settings["debug"] = server_config.getboolean\
734
 
                               ("DEFAULT", "debug")
735
 
    del server_config
736
 
    
737
 
    # Override the settings from the config file with command line
738
 
    # options, if set.
739
 
    for option in ("interface", "address", "port", "debug",
740
 
                   "priority", "servicename", "configdir"):
741
 
        value = getattr(options, option)
742
 
        if value is not None:
743
 
            server_settings[option] = value
744
 
    del options
745
 
    # Now we have our good server settings in "server_settings"
746
 
    
747
 
    debug = server_settings["debug"]
748
 
    
749
 
    if not debug:
750
 
        syslogger.setLevel(logging.WARNING)
751
 
        console.setLevel(logging.WARNING)
752
 
    
753
 
    if server_settings["servicename"] != "Mandos":
754
 
        syslogger.setFormatter(logging.Formatter\
755
 
                               ('Mandos (%s): %%(levelname)s:'
756
 
                                ' %%(message)s'
757
 
                                % server_settings["servicename"]))
758
 
    
759
 
    # Parse config file with clients
760
 
    client_defaults = { "timeout": "1h",
761
 
                        "interval": "5m",
762
 
                        "checker": "fping -q -- %(host)s",
763
 
                        "host": "",
764
 
                        }
765
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
766
 
    client_config.read(os.path.join(server_settings["configdir"],
767
 
                                    "clients.conf"))
768
 
    
769
 
    clients = Set()
770
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
771
 
                                 server_settings["port"]),
772
 
                                tcp_handler,
773
 
                                settings=server_settings,
774
 
                                clients=clients)
775
 
    pidfilename = "/var/run/mandos.pid"
776
 
    try:
777
 
        pidfile = open(pidfilename, "w")
778
 
    except IOError, error:
779
 
        logger.error("Could not open file %r", pidfilename)
780
 
    
781
 
    uid = 65534
782
 
    gid = 65534
783
 
    try:
784
 
        uid = pwd.getpwnam("mandos").pw_uid
785
 
    except KeyError:
786
 
        try:
787
 
            uid = pwd.getpwnam("nobody").pw_uid
788
 
        except KeyError:
789
 
            pass
790
 
    try:
791
 
        gid = pwd.getpwnam("mandos").pw_gid
792
 
    except KeyError:
793
 
        try:
794
 
            gid = pwd.getpwnam("nogroup").pw_gid
795
 
        except KeyError:
796
 
            pass
797
 
    try:
798
 
        os.setuid(uid)
799
 
        os.setgid(gid)
800
 
    except OSError, error:
801
 
        if error[0] != errno.EPERM:
802
 
            raise error
803
 
    
804
 
    global service
805
 
    service = AvahiService(name = server_settings["servicename"],
806
 
                           type = "_mandos._tcp", );
807
 
    if server_settings["interface"]:
808
 
        service.interface = if_nametoindex\
809
 
                            (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;
810
664
    
811
665
    global main_loop
812
666
    global bus
815
669
    DBusGMainLoop(set_as_default=True )
816
670
    main_loop = gobject.MainLoop()
817
671
    bus = dbus.SystemBus()
818
 
    server = dbus.Interface(bus.get_object(avahi.DBUS_NAME,
819
 
                                           avahi.DBUS_PATH_SERVER),
820
 
                            avahi.DBUS_INTERFACE_SERVER)
 
672
    server = dbus.Interface(
 
673
            bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
 
674
            avahi.DBUS_INTERFACE_SERVER )
821
675
    # End of Avahi example code
822
676
    
 
677
    debug = options.debug
 
678
    
 
679
    if debug:
 
680
        console = logging.StreamHandler()
 
681
        # console.setLevel(logging.DEBUG)
 
682
        console.setFormatter(logging.Formatter\
 
683
                             ('%(levelname)s: %(message)s'))
 
684
        logger.addHandler(console)
 
685
        del console
 
686
    
 
687
    clients = Set()
823
688
    def remove_from_clients(client):
824
689
        clients.remove(client)
825
690
        if not clients:
826
 
            logger.critical(u"No clients left, exiting")
827
 
            sys.exit()
 
691
            logger.debug(u"No clients left, exiting")
 
692
            killme()
828
693
    
829
 
    clients.update(Set(Client(name = section,
 
694
    clients.update(Set(Client(name=section,
830
695
                              stop_hook = remove_from_clients,
831
 
                              config
832
 
                              = dict(client_config.items(section)))
 
696
                              **(dict(client_config\
 
697
                                      .items(section))))
833
698
                       for section in client_config.sections()))
834
 
    if not clients:
835
 
        logger.critical(u"No clients defined")
836
 
        sys.exit(1)
837
 
    
838
 
    if debug:
839
 
        # Redirect stdin so all checkers get /dev/null
840
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
841
 
        os.dup2(null, sys.stdin.fileno())
842
 
        if null > 2:
843
 
            os.close(null)
844
 
    else:
845
 
        # No console logging
846
 
        logger.removeHandler(console)
847
 
        # Close all input and output, do double fork, etc.
848
 
        daemon()
849
 
    
850
 
    try:
851
 
        pid = os.getpid()
852
 
        pidfile.write(str(pid) + "\n")
853
 
        pidfile.close()
854
 
        del pidfile
855
 
    except IOError, err:
856
 
        logger.error(u"Could not write to file %r with PID %d",
857
 
                     pidfilename, pid)
858
 
    except NameError:
859
 
        # "pidfile" was never created
860
 
        pass
861
 
    del pidfilename
 
699
    
 
700
    if not debug:
 
701
        daemon(False, False)
862
702
    
863
703
    def cleanup():
864
704
        "Cleanup function; run on exit"
878
718
    
879
719
    if not debug:
880
720
        signal.signal(signal.SIGINT, signal.SIG_IGN)
881
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
882
 
    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())
883
723
    
884
724
    for client in clients:
885
725
        client.start()
886
726
    
887
 
    tcp_server.enable()
888
 
    tcp_server.server_activate()
889
 
    
890
 
    # Find out what port we got
891
 
    service.port = tcp_server.socket.getsockname()[1]
892
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
893
 
                u" scope_id %d" % tcp_server.socket.getsockname())
894
 
    
895
 
    #service.interface = tcp_server.socket.getsockname()[3]
896
 
    
897
 
    try:
898
 
        # From the Avahi example code
899
 
        server.connect_to_signal("StateChanged", server_state_changed)
900
 
        try:
901
 
            server_state_changed(server.GetState())
902
 
        except dbus.exceptions.DBusException, error:
903
 
            logger.critical(u"DBusException: %s", error)
904
 
            sys.exit(1)
905
 
        # End of Avahi example code
906
 
        
907
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
908
 
                             lambda *args, **kwargs:
909
 
                             tcp_server.handle_request\
910
 
                             (*args[2:], **kwargs) or True)
911
 
        
912
 
        logger.debug(u"Starting main loop")
 
727
    tcp_server = IPv6_TCPServer((options.address, options.port),
 
728
                                tcp_handler,
 
729
                                options=options,
 
730
                                clients=clients)
 
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")
913
755
        main_loop_started = True
914
756
        main_loop.run()
915
 
    except AvahiError, error:
916
 
        logger.critical(u"AvahiError: %s" + unicode(error))
917
 
        sys.exit(1)
918
757
    except KeyboardInterrupt:
919
758
        if debug:
920
759
            print
 
760
    
 
761
    sys.exit(exitstatus)
921
762
 
922
763
if __name__ == '__main__':
923
764
    main()