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  • Committer: Teddy Hogeborn
  • Date: 2008-08-04 23:38:26 UTC
  • mfrom: (24.1.20 mandos)
  • Revision ID: teddy@fukt.bsnet.se-20080804233826-idy7v8x36llseue0
* network-protocol.txt: New.

* server.py (daemon): Do the double fork thing.

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server.py
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#     GNU General Public License for more details.
25
25
# 
26
26
# 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
29
# Contact the authors at <mandos@fukt.bsnet.se>.
31
30
# 
55
54
import stat
56
55
import logging
57
56
import logging.handlers
58
 
import pwd
59
57
 
60
58
import dbus
61
59
import gobject
63
61
from dbus.mainloop.glib import DBusGMainLoop
64
62
import ctypes
65
63
 
66
 
version = "1.0"
67
64
 
68
65
logger = logging.Logger('mandos')
69
66
syslogger = logging.handlers.SysLogHandler\
70
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
71
 
             address = "/dev/log")
 
67
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON)
72
68
syslogger.setFormatter(logging.Formatter\
73
 
                        ('Mandos: %(levelname)s: %(message)s'))
 
69
                        ('%(levelname)s: %(message)s'))
74
70
logger.addHandler(syslogger)
 
71
del syslogger
75
72
 
76
 
console = logging.StreamHandler()
77
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
78
 
                                       ' %(message)s'))
79
 
logger.addHandler(console)
80
73
 
81
74
class AvahiError(Exception):
82
75
    def __init__(self, value):
109
102
    """
110
103
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
111
104
                 type = None, port = None, TXT = None, domain = "",
112
 
                 host = "", max_renames = 32768):
 
105
                 host = "", max_renames = 12):
113
106
        self.interface = interface
114
107
        self.name = name
115
108
        self.type = type
121
114
        self.domain = domain
122
115
        self.host = host
123
116
        self.rename_count = 0
124
 
        self.max_renames = max_renames
125
117
    def rename(self):
126
118
        """Derived from the Avahi example code"""
127
119
        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)
 
120
            logger.critical(u"No suitable service name found after %i"
 
121
                            u" retries, exiting.", rename_count)
131
122
            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))
 
123
        name = server.GetAlternativeServiceName(name)
 
124
        logger.error(u"Changing name to %r ...", name)
138
125
        self.remove()
139
126
        self.add()
140
127
        self.rename_count += 1
152
139
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
153
140
            group.connect_to_signal('StateChanged',
154
141
                                    entry_group_state_changed)
155
 
        logger.debug(u"Adding Zeroconf service '%s' of type '%s' ...",
 
142
        logger.debug(u"Adding service '%s' of type '%s' ...",
156
143
                     service.name, service.type)
157
144
        group.AddService(
158
145
                self.interface,         # interface
176
163
    fingerprint: string (40 or 32 hexadecimal digits); used to
177
164
                 uniquely identify the client
178
165
    secret:    bytestring; sent verbatim (over TLS) to client
179
 
    host:      string; available for use by the checker command
 
166
    fqdn:      string (FQDN); available for use by the checker command
180
167
    created:   datetime.datetime(); object creation, not client host
181
168
    last_checked_ok: datetime.datetime() or None if not yet checked OK
182
169
    timeout:   datetime.timedelta(); How long from last_checked_ok
243
230
        else:
244
231
            raise TypeError(u"No secret or secfile for client %s"
245
232
                            % self.name)
246
 
        self.host = config.get("host", "")
 
233
        self.fqdn = config.get("fqdn", "")
247
234
        self.created = datetime.datetime.now()
248
235
        self.last_checked_ok = None
249
236
        self.timeout = string_to_delta(config["timeout"])
272
259
        The possibility that a client might be restarted is left open,
273
260
        but not currently used."""
274
261
        # If this client doesn't have a secret, it is already stopped.
275
 
        if hasattr(self, "secret") and self.secret:
 
262
        if self.secret:
276
263
            logger.info(u"Stopping client %s", self.name)
277
264
            self.secret = None
278
265
        else:
326
313
        if self.checker is None:
327
314
            try:
328
315
                # In case check_command has exactly one % operator
329
 
                command = self.check_command % self.host
 
316
                command = self.check_command % self.fqdn
330
317
            except TypeError:
331
318
                # Escape attributes for the shell
332
319
                escaped_attrs = dict((key, re.escape(str(val)))
341
328
            try:
342
329
                logger.info(u"Starting checker %r for %s",
343
330
                            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
331
                self.checker = subprocess.Popen(command,
349
332
                                                close_fds=True,
350
333
                                                shell=True, cwd="/")
351
334
                self.checker_callback_tag = gobject.child_watch_add\
352
335
                                            (self.checker.pid,
353
336
                                             self.checker_callback)
354
 
            except OSError, error:
 
337
            except subprocess.OSError, error:
355
338
                logger.error(u"Failed to start subprocess: %s",
356
339
                             error)
357
340
        # Re-run this periodically if run by gobject.timeout_add
363
346
            self.checker_callback_tag = None
364
347
        if getattr(self, "checker", None) is None:
365
348
            return
366
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
 
349
        logger.debug("Stopping checker for %(name)s", vars(self))
367
350
        try:
368
351
            os.kill(self.checker.pid, signal.SIGTERM)
369
352
            #os.sleep(0.5)
414
397
    gnutls.library.functions.gnutls_openpgp_crt_import\
415
398
                    (crt, ctypes.byref(datum),
416
399
                     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")
424
400
    # New buffer for the fingerprint
425
401
    buffer = ctypes.create_string_buffer(20)
426
402
    buffer_length = ctypes.c_size_t()
518
494
    Attributes:
519
495
        settings:       Server settings
520
496
        clients:        Set() of Client objects
521
 
        enabled:        Boolean; whether this server is activated yet
522
497
    """
523
498
    address_family = socket.AF_INET6
524
499
    def __init__(self, *args, **kwargs):
528
503
        if "clients" in kwargs:
529
504
            self.clients = kwargs["clients"]
530
505
            del kwargs["clients"]
531
 
        self.enabled = False
532
506
        return super(type(self), self).__init__(*args, **kwargs)
533
507
    def server_bind(self):
534
508
        """This overrides the normal server_bind() function
554
528
                in6addr_any = "::"
555
529
                self.server_address = (in6addr_any,
556
530
                                       self.server_address[1])
557
 
            elif not self.server_address[1]:
 
531
            elif self.server_address[1] is None:
558
532
                self.server_address = (self.server_address[0],
559
533
                                       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
534
            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
535
 
574
536
 
575
537
def string_to_delta(interval):
585
547
    datetime.timedelta(1)
586
548
    >>> string_to_delta(u'1w')
587
549
    datetime.timedelta(7)
588
 
    >>> string_to_delta('5m 30s')
589
 
    datetime.timedelta(0, 330)
590
550
    """
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):
 
551
    try:
 
552
        suffix=unicode(interval[-1])
 
553
        value=int(interval[:-1])
 
554
        if suffix == u"d":
 
555
            delta = datetime.timedelta(value)
 
556
        elif suffix == u"s":
 
557
            delta = datetime.timedelta(0, value)
 
558
        elif suffix == u"m":
 
559
            delta = datetime.timedelta(0, 0, 0, 0, value)
 
560
        elif suffix == u"h":
 
561
            delta = datetime.timedelta(0, 0, 0, 0, 0, value)
 
562
        elif suffix == u"w":
 
563
            delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
 
564
        else:
609
565
            raise ValueError
610
 
        timevalue += delta
611
 
    return timevalue
 
566
    except (ValueError, IndexError):
 
567
        raise ValueError
 
568
    return delta
612
569
 
613
570
 
614
571
def server_state_changed(state):
615
572
    """Derived from the Avahi example code"""
616
573
    if state == avahi.SERVER_COLLISION:
617
 
        logger.error(u"Zeroconf server name collision")
 
574
        logger.error(u"Server name collision")
618
575
        service.remove()
619
576
    elif state == avahi.SERVER_RUNNING:
620
577
        service.add()
622
579
 
623
580
def entry_group_state_changed(state, error):
624
581
    """Derived from the Avahi example code"""
625
 
    logger.debug(u"Avahi state change: %i", state)
 
582
    logger.debug(u"state change: %i", state)
626
583
    
627
584
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
628
 
        logger.debug(u"Zeroconf service established.")
 
585
        logger.debug(u"Service established.")
629
586
    elif state == avahi.ENTRY_GROUP_COLLISION:
630
 
        logger.warning(u"Zeroconf service name collision.")
 
587
        logger.warning(u"Service name collision.")
631
588
        service.rename()
632
589
    elif state == avahi.ENTRY_GROUP_FAILURE:
633
 
        logger.critical(u"Avahi: Error in group state changed %s",
 
590
        logger.critical(u"Error in group state changed %s",
634
591
                        unicode(error))
635
592
        raise AvahiGroupError("State changed: %s", str(error))
636
593
 
659
616
    return if_nametoindex(interface)
660
617
 
661
618
 
662
 
def daemon(nochdir = False, noclose = False):
 
619
def daemon(nochdir, noclose):
663
620
    """See daemon(3).  Standard BSD Unix function.
664
621
    This should really exist as os.daemon, but it doesn't (yet)."""
665
622
    if os.fork():
686
643
    global main_loop_started
687
644
    main_loop_started = False
688
645
    
689
 
    parser = OptionParser(version = "%%prog %s" % version)
 
646
    parser = OptionParser()
690
647
    parser.add_option("-i", "--interface", type="string",
691
648
                      metavar="IF", help="Bind to interface IF")
692
649
    parser.add_option("-a", "--address", type="string",
695
652
                      help="Port number to receive requests on")
696
653
    parser.add_option("--check", action="store_true", default=False,
697
654
                      help="Run self-test")
698
 
    parser.add_option("--debug", action="store_true",
 
655
    parser.add_option("--debug", action="store_true", default=False,
699
656
                      help="Debug mode; run in foreground and log to"
700
657
                      " terminal")
701
658
    parser.add_option("--priority", type="string", help="GnuTLS"
726
683
    # Parse config file for server-global settings
727
684
    server_config = ConfigParser.SafeConfigParser(server_defaults)
728
685
    del server_defaults
729
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
 
686
    server_config.read(os.path.join(options.configdir, "server.conf"))
 
687
    server_section = "server"
730
688
    # Convert the SafeConfigParser object to a dict
731
 
    server_settings = server_config.defaults()
 
689
    server_settings = dict(server_config.items(server_section))
732
690
    # Use getboolean on the boolean config option
733
691
    server_settings["debug"] = server_config.getboolean\
734
 
                               ("DEFAULT", "debug")
 
692
                               (server_section, "debug")
735
693
    del server_config
736
694
    
737
695
    # Override the settings from the config file with command line
744
702
    del options
745
703
    # Now we have our good server settings in "server_settings"
746
704
    
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
705
    # Parse config file with clients
760
706
    client_defaults = { "timeout": "1h",
761
707
                        "interval": "5m",
762
 
                        "checker": "fping -q -- %(host)s",
763
 
                        "host": "",
 
708
                        "checker": "fping -q -- %%(fqdn)s",
764
709
                        }
765
710
    client_config = ConfigParser.SafeConfigParser(client_defaults)
766
711
    client_config.read(os.path.join(server_settings["configdir"],
767
712
                                    "clients.conf"))
768
713
    
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
 
    uid = 65534
776
 
    gid = 65534
777
 
    try:
778
 
        uid = pwd.getpwnam("mandos").pw_uid
779
 
    except KeyError:
780
 
        try:
781
 
            uid = pwd.getpwnam("nobody").pw_uid
782
 
        except KeyError:
783
 
            pass
784
 
    try:
785
 
        gid = pwd.getpwnam("mandos").pw_gid
786
 
    except KeyError:
787
 
        try:
788
 
            gid = pwd.getpwnam("nogroup").pw_gid
789
 
        except KeyError:
790
 
            pass
791
 
    try:
792
 
        os.setuid(uid)
793
 
        os.setgid(gid)
794
 
    except OSError, error:
795
 
        if error[0] != errno.EPERM:
796
 
            raise error
797
 
 
798
714
    global service
799
715
    service = AvahiService(name = server_settings["servicename"],
800
716
                           type = "_mandos._tcp", );
801
717
    if server_settings["interface"]:
802
 
        service.interface = if_nametoindex\
803
 
                            (server_settings["interface"])
 
718
        service.interface = if_nametoindex(server_settings["interface"])
804
719
    
805
720
    global main_loop
806
721
    global bus
809
724
    DBusGMainLoop(set_as_default=True )
810
725
    main_loop = gobject.MainLoop()
811
726
    bus = dbus.SystemBus()
812
 
    server = dbus.Interface(bus.get_object(avahi.DBUS_NAME,
813
 
                                           avahi.DBUS_PATH_SERVER),
814
 
                            avahi.DBUS_INTERFACE_SERVER)
 
727
    server = dbus.Interface(
 
728
            bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
 
729
            avahi.DBUS_INTERFACE_SERVER )
815
730
    # End of Avahi example code
816
731
    
 
732
    debug = server_settings["debug"]
 
733
    
 
734
    if debug:
 
735
        console = logging.StreamHandler()
 
736
        # console.setLevel(logging.DEBUG)
 
737
        console.setFormatter(logging.Formatter\
 
738
                             ('%(levelname)s: %(message)s'))
 
739
        logger.addHandler(console)
 
740
        del console
 
741
    
 
742
    clients = Set()
817
743
    def remove_from_clients(client):
818
744
        clients.remove(client)
819
745
        if not clients:
825
751
                              config
826
752
                              = dict(client_config.items(section)))
827
753
                       for section in client_config.sections()))
828
 
    if not clients:
829
 
        logger.critical(u"No clients defined")
830
 
        sys.exit(1)
831
 
    
832
 
    if debug:
833
 
        # Redirect stdin so all checkers get /dev/null
834
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
835
 
        os.dup2(null, sys.stdin.fileno())
836
 
        if null > 2:
837
 
            os.close(null)
838
 
    else:
839
 
        # No console logging
840
 
        logger.removeHandler(console)
841
 
        # Close all input and output, do double fork, etc.
842
 
        daemon()
843
 
    
844
 
    pidfilename = "/var/run/mandos.pid"
845
 
    pid = os.getpid()
846
 
    try:
847
 
        pidfile = open(pidfilename, "w")
848
 
        pidfile.write(str(pid) + "\n")
849
 
        pidfile.close()
850
 
        del pidfile
851
 
    except IOError, err:
852
 
        logger.error(u"Could not write %s file with PID %d",
853
 
                     pidfilename, os.getpid())
 
754
    
 
755
    if not debug:
 
756
        daemon(False, False)
854
757
    
855
758
    def cleanup():
856
759
        "Cleanup function; run on exit"
876
779
    for client in clients:
877
780
        client.start()
878
781
    
879
 
    tcp_server.enable()
880
 
    tcp_server.server_activate()
881
 
    
 
782
    tcp_server = IPv6_TCPServer((server_settings["address"],
 
783
                                 server_settings["port"]),
 
784
                                tcp_handler,
 
785
                                settings=server_settings,
 
786
                                clients=clients)
882
787
    # Find out what port we got
883
788
    service.port = tcp_server.socket.getsockname()[1]
884
789
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
901
806
                             tcp_server.handle_request\
902
807
                             (*args[2:], **kwargs) or True)
903
808
        
904
 
        logger.debug(u"Starting main loop")
 
809
        logger.debug("Starting main loop")
905
810
        main_loop_started = True
906
811
        main_loop.run()
907
812
    except AvahiError, error: