/mandos/release

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  • Committer: Teddy Hogeborn
  • Date: 2008-08-02 10:48:24 UTC
  • Revision ID: teddy@fukt.bsnet.se-20080802104824-fx0miwp9o4g9r31e
* plugbasedclient.c (struct process): New fields "eof", "completed",
                                      and "status".
  (handle_sigchld): New function.
  (main): Initialize "dir" to NULL to only closedir() it if necessary.
          Move "process_list" to be a global variable to be accessible
          by "handle_sigchld".  Make "handle_sigchld" handle SIGCHLD.
          Remove redundant check for NULL "dir".  Free "filename" when
          no longer used.  Block SIGCHLD around fork()/exec().
          Restore normal signals in child.  Only loop while running
          processes exist.  Print process buffer when the process is
          done and it has emitted EOF, not when it only emits EOF.
          Remove processes from list which exit non-cleanly.  In
          cleaning up, closedir() if necessary.  Bug fix: set next
          pointer correctly when freeing process list.

* plugins.d/passprompt.c (main): Do not ignore SIGQUIT.

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Lines of Context:
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: "AvahiService.add", "AvahiService.remove",
 
10
# "server_state_changed", "entry_group_state_changed", and some lines
 
11
# in "main".
12
12
# 
13
13
# Everything else is
14
14
# Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
61
61
from dbus.mainloop.glib import DBusGMainLoop
62
62
import ctypes
63
63
 
64
 
version = "1.0"
 
64
# Brief description of the operation of this program:
 
65
# 
 
66
# This server announces itself as a Zeroconf service.  Connecting
 
67
# clients use the TLS protocol, with the unusual quirk that this
 
68
# server program acts as a TLS "client" while a connecting client acts
 
69
# as a TLS "server".  The client (acting as a TLS "server") must
 
70
# supply an OpenPGP certificate, and the fingerprint of this
 
71
# certificate is used by this server to look up (in a list read from a
 
72
# file at start time) which binary blob to give the client.  No other
 
73
# authentication or authorization is done by this server.
 
74
 
65
75
 
66
76
logger = logging.Logger('mandos')
67
77
syslogger = logging.handlers.SysLogHandler\
68
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
69
 
             address = "/dev/log")
 
78
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON)
70
79
syslogger.setFormatter(logging.Formatter\
71
 
                        ('Mandos: %(levelname)s: %(message)s'))
 
80
                        ('%(levelname)s: %(message)s'))
72
81
logger.addHandler(syslogger)
 
82
del syslogger
73
83
 
74
 
console = logging.StreamHandler()
75
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
76
 
                                       ' %(message)s'))
77
 
logger.addHandler(console)
78
84
 
79
85
class AvahiError(Exception):
80
86
    def __init__(self, value):
90
96
 
91
97
 
92
98
class AvahiService(object):
93
 
    """An Avahi (Zeroconf) service.
94
 
    Attributes:
 
99
    """
95
100
    interface: integer; avahi.IF_UNSPEC or an interface index.
96
101
               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
 
102
    name = string; Example: "Mandos"
 
103
    type = string; Example: "_mandos._tcp".
 
104
                   See <http://www.dns-sd.org/ServiceTypes.html>
 
105
    port = integer; what port to announce
 
106
    TXT = list of strings; TXT record for the service
 
107
    domain = string; Domain to publish on, default to .local if empty.
 
108
    host = string; Host to publish records for, default to localhost
 
109
                   if empty.
 
110
    max_renames = integer; maximum number of renames
 
111
    rename_count = integer; counter so we only rename after collisions
 
112
                   a sensible number of times
107
113
    """
108
114
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
109
115
                 type = None, port = None, TXT = None, domain = "",
110
 
                 host = "", max_renames = 32768):
 
116
                 host = "", max_renames = 12):
 
117
        """An Avahi (Zeroconf) service. """
111
118
        self.interface = interface
112
119
        self.name = name
113
120
        self.type = type
126
133
                            u" retries, exiting.", rename_count)
127
134
            raise AvahiServiceError("Too many renames")
128
135
        name = server.GetAlternativeServiceName(name)
129
 
        logger.error(u"Changing name to %r ...", name)
130
 
        syslogger.setFormatter(logging.Formatter\
131
 
                               ('Mandos (%s): %%(levelname)s:'
132
 
                               ' %%(message)s' % name))
 
136
        logger.notice(u"Changing name to %r ...", name)
133
137
        self.remove()
134
138
        self.add()
135
139
        self.rename_count += 1
171
175
    fingerprint: string (40 or 32 hexadecimal digits); used to
172
176
                 uniquely identify the client
173
177
    secret:    bytestring; sent verbatim (over TLS) to client
174
 
    host:      string; available for use by the checker command
 
178
    fqdn:      string (FQDN); available for use by the checker command
175
179
    created:   datetime.datetime(); object creation, not client host
176
180
    last_checked_ok: datetime.datetime() or None if not yet checked OK
177
181
    timeout:   datetime.timedelta(); How long from last_checked_ok
217
221
    interval = property(lambda self: self._interval,
218
222
                        _set_interval)
219
223
    del _set_interval
220
 
    def __init__(self, name = None, stop_hook=None, config={}):
221
 
        """Note: the 'checker' key in 'config' sets the
222
 
        'checker_command' attribute and *not* the 'checker'
223
 
        attribute."""
 
224
    def __init__(self, name=None, stop_hook=None, fingerprint=None,
 
225
                 secret=None, secfile=None, fqdn=None, timeout=None,
 
226
                 interval=-1, checker=None):
 
227
        """Note: the 'checker' argument sets the 'checker_command'
 
228
        attribute and not the 'checker' attribute.."""
224
229
        self.name = name
225
230
        logger.debug(u"Creating client %r", self.name)
226
 
        # Uppercase and remove spaces from fingerprint for later
227
 
        # comparison purposes with return value from the fingerprint()
228
 
        # function
229
 
        self.fingerprint = config["fingerprint"].upper()\
230
 
                           .replace(u" ", u"")
 
231
        # Uppercase and remove spaces from fingerprint
 
232
        # for later comparison purposes with return value of
 
233
        # the fingerprint() function
 
234
        self.fingerprint = fingerprint.upper().replace(u" ", u"")
231
235
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
232
 
        if "secret" in config:
233
 
            self.secret = config["secret"].decode(u"base64")
234
 
        elif "secfile" in config:
235
 
            sf = open(config["secfile"])
 
236
        if secret:
 
237
            self.secret = secret.decode(u"base64")
 
238
        elif secfile:
 
239
            sf = open(secfile)
236
240
            self.secret = sf.read()
237
241
            sf.close()
238
242
        else:
239
243
            raise TypeError(u"No secret or secfile for client %s"
240
244
                            % self.name)
241
 
        self.host = config.get("host", "")
 
245
        self.fqdn = fqdn
242
246
        self.created = datetime.datetime.now()
243
247
        self.last_checked_ok = None
244
 
        self.timeout = string_to_delta(config["timeout"])
245
 
        self.interval = string_to_delta(config["interval"])
 
248
        self.timeout = string_to_delta(timeout)
 
249
        self.interval = string_to_delta(interval)
246
250
        self.stop_hook = stop_hook
247
251
        self.checker = None
248
252
        self.checker_initiator_tag = None
249
253
        self.stop_initiator_tag = None
250
254
        self.checker_callback_tag = None
251
 
        self.check_command = config["checker"]
 
255
        self.check_command = checker
252
256
    def start(self):
253
257
        """Start this client's checker and timeout hooks"""
254
258
        # Schedule a new checker to be started an 'interval' from now,
267
271
        The possibility that a client might be restarted is left open,
268
272
        but not currently used."""
269
273
        # If this client doesn't have a secret, it is already stopped.
270
 
        if hasattr(self, "secret") and self.secret:
271
 
            logger.info(u"Stopping client %s", self.name)
 
274
        if self.secret:
 
275
            logger.debug(u"Stopping client %s", self.name)
272
276
            self.secret = None
273
277
        else:
274
278
            return False
293
297
        self.checker = None
294
298
        if os.WIFEXITED(condition) \
295
299
               and (os.WEXITSTATUS(condition) == 0):
296
 
            logger.info(u"Checker for %(name)s succeeded",
297
 
                        vars(self))
 
300
            logger.debug(u"Checker for %(name)s succeeded",
 
301
                         vars(self))
298
302
            self.last_checked_ok = now
299
303
            gobject.source_remove(self.stop_initiator_tag)
300
304
            self.stop_initiator_tag = gobject.timeout_add\
304
308
            logger.warning(u"Checker for %(name)s crashed?",
305
309
                           vars(self))
306
310
        else:
307
 
            logger.info(u"Checker for %(name)s failed",
308
 
                        vars(self))
 
311
            logger.debug(u"Checker for %(name)s failed",
 
312
                         vars(self))
309
313
    def start_checker(self):
310
314
        """Start a new checker subprocess if one is not running.
311
315
        If a checker already exists, leave it running and do
321
325
        if self.checker is None:
322
326
            try:
323
327
                # In case check_command has exactly one % operator
324
 
                command = self.check_command % self.host
 
328
                command = self.check_command % self.fqdn
325
329
            except TypeError:
326
330
                # Escape attributes for the shell
327
331
                escaped_attrs = dict((key, re.escape(str(val)))
334
338
                                 u' %s', self.check_command, error)
335
339
                    return True # Try again later
336
340
            try:
337
 
                logger.info(u"Starting checker %r for %s",
338
 
                            command, self.name)
 
341
                logger.debug(u"Starting checker %r for %s",
 
342
                             command, self.name)
339
343
                self.checker = subprocess.Popen(command,
340
344
                                                close_fds=True,
341
345
                                                shell=True, cwd="/")
354
358
            self.checker_callback_tag = None
355
359
        if getattr(self, "checker", None) is None:
356
360
            return
357
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
 
361
        logger.debug("Stopping checker for %(name)s", vars(self))
358
362
        try:
359
363
            os.kill(self.checker.pid, signal.SIGTERM)
360
364
            #os.sleep(0.5)
392
396
 
393
397
def fingerprint(openpgp):
394
398
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
 
399
    # New empty GnuTLS certificate
 
400
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
401
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
402
        (ctypes.byref(crt))
395
403
    # New GnuTLS "datum" with the OpenPGP public key
396
404
    datum = gnutls.library.types.gnutls_datum_t\
397
405
        (ctypes.cast(ctypes.c_char_p(openpgp),
398
406
                     ctypes.POINTER(ctypes.c_ubyte)),
399
407
         ctypes.c_uint(len(openpgp)))
400
 
    # New empty GnuTLS certificate
401
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
402
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
403
 
        (ctypes.byref(crt))
404
408
    # Import the OpenPGP public key into the certificate
405
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
406
 
                    (crt, ctypes.byref(datum),
407
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
 
409
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
 
410
        (crt,
 
411
         ctypes.byref(datum),
 
412
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
408
413
    # New buffer for the fingerprint
409
414
    buffer = ctypes.create_string_buffer(20)
410
415
    buffer_length = ctypes.c_size_t()
426
431
    Note: This will run in its own forked process."""
427
432
    
428
433
    def handle(self):
429
 
        logger.info(u"TCP connection from: %s",
 
434
        logger.debug(u"TCP connection from: %s",
430
435
                     unicode(self.client_address))
431
436
        session = gnutls.connection.ClientSession\
432
437
                  (self.request, gnutls.connection.X509Credentials())
433
 
        
434
 
        line = self.request.makefile().readline()
435
 
        logger.debug(u"Protocol version: %r", line)
436
 
        try:
437
 
            if int(line.strip().split()[0]) > 1:
438
 
                raise RuntimeError
439
 
        except (ValueError, IndexError, RuntimeError), error:
440
 
            logger.error(u"Unknown protocol version: %s", error)
441
 
            return
442
 
        
443
438
        # Note: gnutls.connection.X509Credentials is really a generic
444
439
        # GnuTLS certificate credentials object so long as no X.509
445
440
        # keys are added to it.  Therefore, we can use it here despite
458
453
        try:
459
454
            session.handshake()
460
455
        except gnutls.errors.GNUTLSError, error:
461
 
            logger.warning(u"Handshake failed: %s", error)
 
456
            logger.debug(u"Handshake failed: %s", error)
462
457
            # Do not run session.bye() here: the session is not
463
458
            # established.  Just abandon the request.
464
459
            return
465
460
        try:
466
461
            fpr = fingerprint(peer_certificate(session))
467
462
        except (TypeError, gnutls.errors.GNUTLSError), error:
468
 
            logger.warning(u"Bad certificate: %s", error)
 
463
            logger.debug(u"Bad certificate: %s", error)
469
464
            session.bye()
470
465
            return
471
466
        logger.debug(u"Fingerprint: %s", fpr)
475
470
                client = c
476
471
                break
477
472
        if not client:
478
 
            logger.warning(u"Client not found for fingerprint: %s",
479
 
                           fpr)
 
473
            logger.debug(u"Client not found for fingerprint: %s", fpr)
480
474
            session.bye()
481
475
            return
482
476
        # Have to check if client.still_valid(), since it is possible
483
477
        # that the client timed out while establishing the GnuTLS
484
478
        # session.
485
479
        if not client.still_valid():
486
 
            logger.warning(u"Client %(name)s is invalid",
487
 
                           vars(client))
 
480
            logger.debug(u"Client %(name)s is invalid", vars(client))
488
481
            session.bye()
489
482
            return
490
483
        sent_size = 0
525
518
                                       self.settings["interface"])
526
519
            except socket.error, error:
527
520
                if error[0] == errno.EPERM:
528
 
                    logger.error(u"No permission to"
529
 
                                 u" bind to interface %s",
530
 
                                 self.settings["interface"])
 
521
                    logger.warning(u"No permission to"
 
522
                                   u" bind to interface %s",
 
523
                                   self.settings["interface"])
531
524
                else:
532
525
                    raise error
533
526
        # Only bind(2) the socket if we really need to.
536
529
                in6addr_any = "::"
537
530
                self.server_address = (in6addr_any,
538
531
                                       self.server_address[1])
539
 
            elif not self.server_address[1]:
 
532
            elif self.server_address[1] is None:
540
533
                self.server_address = (self.server_address[0],
541
534
                                       0)
542
 
#                 if self.settings["interface"]:
543
 
#                     self.server_address = (self.server_address[0],
544
 
#                                            0, # port
545
 
#                                            0, # flowinfo
546
 
#                                            if_nametoindex
547
 
#                                            (self.settings
548
 
#                                             ["interface"]))
549
535
            return super(type(self), self).server_bind()
550
536
 
551
537
 
586
572
def server_state_changed(state):
587
573
    """Derived from the Avahi example code"""
588
574
    if state == avahi.SERVER_COLLISION:
589
 
        logger.error(u"Server name collision")
 
575
        logger.warning(u"Server name collision")
590
576
        service.remove()
591
577
    elif state == avahi.SERVER_RUNNING:
592
578
        service.add()
606
592
                        unicode(error))
607
593
        raise AvahiGroupError("State changed: %s", str(error))
608
594
 
609
 
def if_nametoindex(interface):
 
595
def if_nametoindex(interface, _func=[None]):
610
596
    """Call the C function if_nametoindex(), or equivalent"""
611
 
    global if_nametoindex
 
597
    if _func[0] is not None:
 
598
        return _func[0](interface)
612
599
    try:
613
600
        if "ctypes.util" not in sys.modules:
614
601
            import ctypes.util
615
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
616
 
            (ctypes.util.find_library("c")).if_nametoindex
 
602
        while True:
 
603
            try:
 
604
                libc = ctypes.cdll.LoadLibrary\
 
605
                       (ctypes.util.find_library("c"))
 
606
                _func[0] = libc.if_nametoindex
 
607
                return _func[0](interface)
 
608
            except IOError, e:
 
609
                if e != errno.EINTR:
 
610
                    raise
617
611
    except (OSError, AttributeError):
618
612
        if "struct" not in sys.modules:
619
613
            import struct
620
614
        if "fcntl" not in sys.modules:
621
615
            import fcntl
622
 
        def if_nametoindex(interface):
 
616
        def the_hard_way(interface):
623
617
            "Get an interface index the hard way, i.e. using fcntl()"
624
618
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
625
619
            s = socket.socket()
628
622
            s.close()
629
623
            interface_index = struct.unpack("I", ifreq[16:20])[0]
630
624
            return interface_index
631
 
    return if_nametoindex(interface)
632
 
 
633
 
 
634
 
def daemon(nochdir = False, noclose = False):
 
625
        _func[0] = the_hard_way
 
626
        return _func[0](interface)
 
627
 
 
628
 
 
629
def daemon(nochdir, noclose):
635
630
    """See daemon(3).  Standard BSD Unix function.
636
631
    This should really exist as os.daemon, but it doesn't (yet)."""
637
632
    if os.fork():
639
634
    os.setsid()
640
635
    if not nochdir:
641
636
        os.chdir("/")
642
 
    if os.fork():
643
 
        sys.exit()
644
637
    if not noclose:
645
638
        # Close all standard open file descriptors
646
639
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
658
651
    global main_loop_started
659
652
    main_loop_started = False
660
653
    
661
 
    parser = OptionParser(version = "%%prog %s" % version)
 
654
    parser = OptionParser()
662
655
    parser.add_option("-i", "--interface", type="string",
663
656
                      metavar="IF", help="Bind to interface IF")
664
657
    parser.add_option("-a", "--address", type="string",
667
660
                      help="Port number to receive requests on")
668
661
    parser.add_option("--check", action="store_true", default=False,
669
662
                      help="Run self-test")
670
 
    parser.add_option("--debug", action="store_true",
 
663
    parser.add_option("--debug", action="store_true", default=False,
671
664
                      help="Debug mode; run in foreground and log to"
672
665
                      " terminal")
673
666
    parser.add_option("--priority", type="string", help="GnuTLS"
698
691
    # Parse config file for server-global settings
699
692
    server_config = ConfigParser.SafeConfigParser(server_defaults)
700
693
    del server_defaults
701
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
 
694
    server_config.read(os.path.join(options.configdir, "server.conf"))
702
695
    server_section = "server"
703
696
    # Convert the SafeConfigParser object to a dict
704
697
    server_settings = dict(server_config.items(server_section))
717
710
    del options
718
711
    # Now we have our good server settings in "server_settings"
719
712
    
720
 
    debug = server_settings["debug"]
721
 
    
722
 
    if not debug:
723
 
        syslogger.setLevel(logging.WARNING)
724
 
        console.setLevel(logging.WARNING)
725
 
    
726
 
    if server_settings["servicename"] != "Mandos":
727
 
        syslogger.setFormatter(logging.Formatter\
728
 
                               ('Mandos (%s): %%(levelname)s:'
729
 
                                ' %%(message)s'
730
 
                                % server_settings["servicename"]))
731
 
    
732
713
    # Parse config file with clients
733
714
    client_defaults = { "timeout": "1h",
734
715
                        "interval": "5m",
735
 
                        "checker": "fping -q -- %%(host)s",
 
716
                        "checker": "fping -q -- %%(fqdn)s",
736
717
                        }
737
718
    client_config = ConfigParser.SafeConfigParser(client_defaults)
738
719
    client_config.read(os.path.join(server_settings["configdir"],
756
737
            avahi.DBUS_INTERFACE_SERVER )
757
738
    # End of Avahi example code
758
739
    
 
740
    debug = server_settings["debug"]
 
741
    
 
742
    if debug:
 
743
        console = logging.StreamHandler()
 
744
        # console.setLevel(logging.DEBUG)
 
745
        console.setFormatter(logging.Formatter\
 
746
                             ('%(levelname)s: %(message)s'))
 
747
        logger.addHandler(console)
 
748
        del console
 
749
    
759
750
    clients = Set()
760
751
    def remove_from_clients(client):
761
752
        clients.remove(client)
762
753
        if not clients:
763
 
            logger.critical(u"No clients left, exiting")
 
754
            logger.debug(u"No clients left, exiting")
764
755
            sys.exit()
765
756
    
766
 
    clients.update(Set(Client(name = section,
 
757
    clients.update(Set(Client(name=section,
767
758
                              stop_hook = remove_from_clients,
768
 
                              config
769
 
                              = dict(client_config.items(section)))
 
759
                              **(dict(client_config\
 
760
                                      .items(section))))
770
761
                       for section in client_config.sections()))
771
 
    if not clients:
772
 
        logger.critical(u"No clients defined")
773
 
        sys.exit(1)
774
762
    
775
763
    if not debug:
776
 
        logger.removeHandler(console)
777
 
        daemon()
778
 
    
779
 
    pidfilename = "/var/run/mandos/mandos.pid"
780
 
    pid = os.getpid()
781
 
    try:
782
 
        pidfile = open(pidfilename, "w")
783
 
        pidfile.write(str(pid) + "\n")
784
 
        pidfile.close()
785
 
        del pidfile
786
 
    except IOError, err:
787
 
        logger.error(u"Could not write %s file with PID %d",
788
 
                     pidfilename, os.getpid())
 
764
        daemon(False, False)
789
765
    
790
766
    def cleanup():
791
767
        "Cleanup function; run on exit"
818
794
                                clients=clients)
819
795
    # Find out what port we got
820
796
    service.port = tcp_server.socket.getsockname()[1]
821
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
822
 
                u" scope_id %d" % tcp_server.socket.getsockname())
 
797
    logger.debug(u"Now listening on address %r, port %d, flowinfo %d,"
 
798
                 u" scope_id %d" % tcp_server.socket.getsockname())
823
799
    
824
800
    #service.interface = tcp_server.socket.getsockname()[3]
825
801
    
838
814
                             tcp_server.handle_request\
839
815
                             (*args[2:], **kwargs) or True)
840
816
        
841
 
        logger.debug(u"Starting main loop")
 
817
        logger.debug("Starting main loop")
842
818
        main_loop_started = True
843
819
        main_loop.run()
844
820
    except AvahiError, error: