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  • Committer: Teddy Hogeborn
  • Date: 2008-08-07 22:30:45 UTC
  • Revision ID: teddy@fukt.bsnet.se-20080807223045-58y7vw4bcqlmesv5
* network-protocol.txt: Flip table.

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Lines of Context:
mandos
11
11
# and some lines in "main".
12
12
# 
13
13
# Everything else is
14
 
# Copyright © 2008 Teddy Hogeborn & Björn Påhlsson
 
14
# Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
15
15
# 
16
16
# This program is free software: you can redistribute it and/or modify
17
17
# it under the terms of the GNU General Public License as published by
24
24
#     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
# 
34
33
 
35
34
import SocketServer
36
35
import socket
 
36
import select
37
37
from optparse import OptionParser
38
38
import datetime
39
39
import errno
54
54
import stat
55
55
import logging
56
56
import logging.handlers
57
 
import pwd
58
57
 
59
58
import dbus
60
59
import gobject
61
60
import avahi
62
61
from dbus.mainloop.glib import DBusGMainLoop
63
62
import ctypes
64
 
import ctypes.util
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):
83
76
        self.value = value
84
 
        super(AvahiError, self).__init__()
85
77
    def __str__(self):
86
78
        return repr(self.value)
87
79
 
109
101
                  a sensible number of times
110
102
    """
111
103
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
112
 
                 servicetype = None, port = None, TXT = None, domain = "",
113
 
                 host = "", max_renames = 32768):
 
104
                 type = None, port = None, TXT = None, domain = "",
 
105
                 host = "", max_renames = 12):
114
106
        self.interface = interface
115
107
        self.name = name
116
 
        self.type = servicetype
 
108
        self.type = type
117
109
        self.port = port
118
110
        if TXT is None:
119
111
            self.TXT = []
122
114
        self.domain = domain
123
115
        self.host = host
124
116
        self.rename_count = 0
125
 
        self.max_renames = max_renames
126
117
    def rename(self):
127
118
        """Derived from the Avahi example code"""
128
119
        if self.rename_count >= self.max_renames:
129
 
            logger.critical(u"No suitable Zeroconf service name found"
130
 
                            u" after %i retries, exiting.",
131
 
                            self.rename_count)
 
120
            logger.critical(u"No suitable service name found after %i"
 
121
                            u" retries, exiting.", rename_count)
132
122
            raise AvahiServiceError("Too many renames")
133
 
        self.name = server.GetAlternativeServiceName(self.name)
134
 
        logger.info(u"Changing Zeroconf service name to %r ...",
135
 
                    str(self.name))
136
 
        syslogger.setFormatter(logging.Formatter\
137
 
                               ('Mandos (%s): %%(levelname)s:'
138
 
                               ' %%(message)s' % self.name))
 
123
        name = server.GetAlternativeServiceName(name)
 
124
        logger.error(u"Changing name to %r ...", name)
139
125
        self.remove()
140
126
        self.add()
141
127
        self.rename_count += 1
153
139
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
154
140
            group.connect_to_signal('StateChanged',
155
141
                                    entry_group_state_changed)
156
 
        logger.debug(u"Adding Zeroconf service '%s' of type '%s' ...",
 
142
        logger.debug(u"Adding service '%s' of type '%s' ...",
157
143
                     service.name, service.type)
158
144
        group.AddService(
159
145
                self.interface,         # interface
177
163
    fingerprint: string (40 or 32 hexadecimal digits); used to
178
164
                 uniquely identify the client
179
165
    secret:    bytestring; sent verbatim (over TLS) to client
180
 
    host:      string; available for use by the checker command
 
166
    fqdn:      string (FQDN); available for use by the checker command
181
167
    created:   datetime.datetime(); object creation, not client host
182
168
    last_checked_ok: datetime.datetime() or None if not yet checked OK
183
169
    timeout:   datetime.timedelta(); How long from last_checked_ok
223
209
    interval = property(lambda self: self._interval,
224
210
                        _set_interval)
225
211
    del _set_interval
226
 
    def __init__(self, name = None, stop_hook=None, config=None):
 
212
    def __init__(self, name = None, stop_hook=None, config={}):
227
213
        """Note: the 'checker' key in 'config' sets the
228
214
        'checker_command' attribute and *not* the 'checker'
229
215
        attribute."""
230
 
        if config is None:
231
 
            config = {}
232
216
        self.name = name
233
217
        logger.debug(u"Creating client %r", self.name)
234
218
        # Uppercase and remove spaces from fingerprint for later
240
224
        if "secret" in config:
241
225
            self.secret = config["secret"].decode(u"base64")
242
226
        elif "secfile" in config:
243
 
            secfile = open(config["secfile"])
244
 
            self.secret = secfile.read()
245
 
            secfile.close()
 
227
            sf = open(config["secfile"])
 
228
            self.secret = sf.read()
 
229
            sf.close()
246
230
        else:
247
231
            raise TypeError(u"No secret or secfile for client %s"
248
232
                            % self.name)
249
 
        self.host = config.get("host", "")
 
233
        self.fqdn = config.get("fqdn", "")
250
234
        self.created = datetime.datetime.now()
251
235
        self.last_checked_ok = None
252
236
        self.timeout = string_to_delta(config["timeout"])
275
259
        The possibility that a client might be restarted is left open,
276
260
        but not currently used."""
277
261
        # If this client doesn't have a secret, it is already stopped.
278
 
        if hasattr(self, "secret") and self.secret:
 
262
        if self.secret:
279
263
            logger.info(u"Stopping client %s", self.name)
280
264
            self.secret = None
281
265
        else:
329
313
        if self.checker is None:
330
314
            try:
331
315
                # In case check_command has exactly one % operator
332
 
                command = self.check_command % self.host
 
316
                command = self.check_command % self.fqdn
333
317
            except TypeError:
334
318
                # Escape attributes for the shell
335
319
                escaped_attrs = dict((key, re.escape(str(val)))
344
328
            try:
345
329
                logger.info(u"Starting checker %r for %s",
346
330
                            command, self.name)
347
 
                # We don't need to redirect stdout and stderr, since
348
 
                # in normal mode, that is already done by daemon(),
349
 
                # and in debug mode we don't want to.  (Stdin is
350
 
                # always replaced by /dev/null.)
351
331
                self.checker = subprocess.Popen(command,
352
332
                                                close_fds=True,
353
333
                                                shell=True, cwd="/")
354
334
                self.checker_callback_tag = gobject.child_watch_add\
355
335
                                            (self.checker.pid,
356
336
                                             self.checker_callback)
357
 
            except OSError, error:
 
337
            except subprocess.OSError, error:
358
338
                logger.error(u"Failed to start subprocess: %s",
359
339
                             error)
360
340
        # Re-run this periodically if run by gobject.timeout_add
366
346
            self.checker_callback_tag = None
367
347
        if getattr(self, "checker", None) is None:
368
348
            return
369
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
 
349
        logger.debug("Stopping checker for %(name)s", vars(self))
370
350
        try:
371
351
            os.kill(self.checker.pid, signal.SIGTERM)
372
352
            #os.sleep(0.5)
417
397
    gnutls.library.functions.gnutls_openpgp_crt_import\
418
398
                    (crt, ctypes.byref(datum),
419
399
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
420
 
    # Verify the self signature in the key
421
 
    crtverify = ctypes.c_uint()
422
 
    gnutls.library.functions.gnutls_openpgp_crt_verify_self\
423
 
        (crt, 0, ctypes.byref(crtverify))
424
 
    if crtverify.value != 0:
425
 
        gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
426
 
        raise gnutls.errors.CertificateSecurityError("Verify failed")
427
400
    # New buffer for the fingerprint
428
 
    buf = ctypes.create_string_buffer(20)
429
 
    buf_len = ctypes.c_size_t()
 
401
    buffer = ctypes.create_string_buffer(20)
 
402
    buffer_length = ctypes.c_size_t()
430
403
    # Get the fingerprint from the certificate into the buffer
431
404
    gnutls.library.functions.gnutls_openpgp_crt_get_fingerprint\
432
 
        (crt, ctypes.byref(buf), ctypes.byref(buf_len))
 
405
        (crt, ctypes.byref(buffer), ctypes.byref(buffer_length))
433
406
    # Deinit the certificate
434
407
    gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
435
408
    # Convert the buffer to a Python bytestring
436
 
    fpr = ctypes.string_at(buf, buf_len.value)
 
409
    fpr = ctypes.string_at(buffer, buffer_length.value)
437
410
    # Convert the bytestring to hexadecimal notation
438
411
    hex_fpr = u''.join(u"%02X" % ord(char) for char in fpr)
439
412
    return hex_fpr
440
413
 
441
414
 
442
 
class TCP_handler(SocketServer.BaseRequestHandler, object):
 
415
class tcp_handler(SocketServer.BaseRequestHandler, object):
443
416
    """A TCP request handler class.
444
417
    Instantiated by IPv6_TCPServer for each request to handle it.
445
418
    Note: This will run in its own forked process."""
472
445
        if self.server.settings["priority"]:
473
446
            priority = self.server.settings["priority"]
474
447
        gnutls.library.functions.gnutls_priority_set_direct\
475
 
            (session._c_object, priority, None)
 
448
            (session._c_object, priority, None);
476
449
        
477
450
        try:
478
451
            session.handshake()
521
494
    Attributes:
522
495
        settings:       Server settings
523
496
        clients:        Set() of Client objects
524
 
        enabled:        Boolean; whether this server is activated yet
525
497
    """
526
498
    address_family = socket.AF_INET6
527
499
    def __init__(self, *args, **kwargs):
531
503
        if "clients" in kwargs:
532
504
            self.clients = kwargs["clients"]
533
505
            del kwargs["clients"]
534
 
        self.enabled = False
535
 
        super(IPv6_TCPServer, self).__init__(*args, **kwargs)
 
506
        return super(type(self), self).__init__(*args, **kwargs)
536
507
    def server_bind(self):
537
508
        """This overrides the normal server_bind() function
538
509
        to bind to an interface if one was specified, and also NOT to
557
528
                in6addr_any = "::"
558
529
                self.server_address = (in6addr_any,
559
530
                                       self.server_address[1])
560
 
            elif not self.server_address[1]:
 
531
            elif self.server_address[1] is None:
561
532
                self.server_address = (self.server_address[0],
562
533
                                       0)
563
 
#                 if self.settings["interface"]:
564
 
#                     self.server_address = (self.server_address[0],
565
 
#                                            0, # port
566
 
#                                            0, # flowinfo
567
 
#                                            if_nametoindex
568
 
#                                            (self.settings
569
 
#                                             ["interface"]))
570
 
            return super(IPv6_TCPServer, self).server_bind()
571
 
    def server_activate(self):
572
 
        if self.enabled:
573
 
            return super(IPv6_TCPServer, self).server_activate()
574
 
    def enable(self):
575
 
        self.enabled = True
 
534
            return super(type(self), self).server_bind()
576
535
 
577
536
 
578
537
def string_to_delta(interval):
588
547
    datetime.timedelta(1)
589
548
    >>> string_to_delta(u'1w')
590
549
    datetime.timedelta(7)
591
 
    >>> string_to_delta('5m 30s')
592
 
    datetime.timedelta(0, 330)
593
550
    """
594
 
    timevalue = datetime.timedelta(0)
595
 
    for s in interval.split():
596
 
        try:
597
 
            suffix = unicode(s[-1])
598
 
            value = int(s[:-1])
599
 
            if suffix == u"d":
600
 
                delta = datetime.timedelta(value)
601
 
            elif suffix == u"s":
602
 
                delta = datetime.timedelta(0, value)
603
 
            elif suffix == u"m":
604
 
                delta = datetime.timedelta(0, 0, 0, 0, value)
605
 
            elif suffix == u"h":
606
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, value)
607
 
            elif suffix == u"w":
608
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
609
 
            else:
610
 
                raise ValueError
611
 
        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:
612
565
            raise ValueError
613
 
        timevalue += delta
614
 
    return timevalue
 
566
    except (ValueError, IndexError):
 
567
        raise ValueError
 
568
    return delta
615
569
 
616
570
 
617
571
def server_state_changed(state):
618
572
    """Derived from the Avahi example code"""
619
573
    if state == avahi.SERVER_COLLISION:
620
 
        logger.error(u"Zeroconf server name collision")
 
574
        logger.error(u"Server name collision")
621
575
        service.remove()
622
576
    elif state == avahi.SERVER_RUNNING:
623
577
        service.add()
625
579
 
626
580
def entry_group_state_changed(state, error):
627
581
    """Derived from the Avahi example code"""
628
 
    logger.debug(u"Avahi state change: %i", state)
 
582
    logger.debug(u"state change: %i", state)
629
583
    
630
584
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
631
 
        logger.debug(u"Zeroconf service established.")
 
585
        logger.debug(u"Service established.")
632
586
    elif state == avahi.ENTRY_GROUP_COLLISION:
633
 
        logger.warning(u"Zeroconf service name collision.")
 
587
        logger.warning(u"Service name collision.")
634
588
        service.rename()
635
589
    elif state == avahi.ENTRY_GROUP_FAILURE:
636
 
        logger.critical(u"Avahi: Error in group state changed %s",
 
590
        logger.critical(u"Error in group state changed %s",
637
591
                        unicode(error))
638
592
        raise AvahiGroupError("State changed: %s", str(error))
639
593
 
641
595
    """Call the C function if_nametoindex(), or equivalent"""
642
596
    global if_nametoindex
643
597
    try:
 
598
        if "ctypes.util" not in sys.modules:
 
599
            import ctypes.util
644
600
        if_nametoindex = ctypes.cdll.LoadLibrary\
645
601
            (ctypes.util.find_library("c")).if_nametoindex
646
602
    except (OSError, AttributeError):
684
640
 
685
641
 
686
642
def main():
687
 
    parser = OptionParser(version = "%%prog %s" % version)
 
643
    global main_loop_started
 
644
    main_loop_started = False
 
645
    
 
646
    parser = OptionParser()
688
647
    parser.add_option("-i", "--interface", type="string",
689
648
                      metavar="IF", help="Bind to interface IF")
690
649
    parser.add_option("-a", "--address", type="string",
693
652
                      help="Port number to receive requests on")
694
653
    parser.add_option("--check", action="store_true", default=False,
695
654
                      help="Run self-test")
696
 
    parser.add_option("--debug", action="store_true",
 
655
    parser.add_option("--debug", action="store_true", default=False,
697
656
                      help="Debug mode; run in foreground and log to"
698
657
                      " terminal")
699
658
    parser.add_option("--priority", type="string", help="GnuTLS"
704
663
                      default="/etc/mandos", metavar="DIR",
705
664
                      help="Directory to search for configuration"
706
665
                      " files")
707
 
    options = parser.parse_args()[0]
 
666
    (options, args) = parser.parse_args()
708
667
    
709
668
    if options.check:
710
669
        import doctest
725
684
    server_config = ConfigParser.SafeConfigParser(server_defaults)
726
685
    del server_defaults
727
686
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
 
687
    server_section = "server"
728
688
    # Convert the SafeConfigParser object to a dict
729
 
    server_settings = server_config.defaults()
 
689
    server_settings = dict(server_config.items(server_section))
730
690
    # Use getboolean on the boolean config option
731
691
    server_settings["debug"] = server_config.getboolean\
732
 
                               ("DEFAULT", "debug")
 
692
                               (server_section, "debug")
733
693
    del server_config
734
694
    
735
695
    # Override the settings from the config file with command line
742
702
    del options
743
703
    # Now we have our good server settings in "server_settings"
744
704
    
745
 
    debug = server_settings["debug"]
746
 
    
747
 
    if not debug:
748
 
        syslogger.setLevel(logging.WARNING)
749
 
        console.setLevel(logging.WARNING)
750
 
    
751
 
    if server_settings["servicename"] != "Mandos":
752
 
        syslogger.setFormatter(logging.Formatter\
753
 
                               ('Mandos (%s): %%(levelname)s:'
754
 
                                ' %%(message)s'
755
 
                                % server_settings["servicename"]))
756
 
    
757
705
    # Parse config file with clients
758
706
    client_defaults = { "timeout": "1h",
759
707
                        "interval": "5m",
760
 
                        "checker": "fping -q -- %(host)s",
761
 
                        "host": "",
 
708
                        "checker": "fping -q -- %%(fqdn)s",
762
709
                        }
763
710
    client_config = ConfigParser.SafeConfigParser(client_defaults)
764
711
    client_config.read(os.path.join(server_settings["configdir"],
765
712
                                    "clients.conf"))
766
713
    
767
 
    clients = Set()
768
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
769
 
                                 server_settings["port"]),
770
 
                                TCP_handler,
771
 
                                settings=server_settings,
772
 
                                clients=clients)
773
 
    pidfilename = "/var/run/mandos.pid"
774
 
    try:
775
 
        pidfile = open(pidfilename, "w")
776
 
    except IOError, error:
777
 
        logger.error("Could not open file %r", pidfilename)
778
 
    
779
 
    uid = 65534
780
 
    gid = 65534
781
 
    try:
782
 
        uid = pwd.getpwnam("mandos").pw_uid
783
 
    except KeyError:
784
 
        try:
785
 
            uid = pwd.getpwnam("nobody").pw_uid
786
 
        except KeyError:
787
 
            pass
788
 
    try:
789
 
        gid = pwd.getpwnam("mandos").pw_gid
790
 
    except KeyError:
791
 
        try:
792
 
            gid = pwd.getpwnam("nogroup").pw_gid
793
 
        except KeyError:
794
 
            pass
795
 
    try:
796
 
        os.setuid(uid)
797
 
        os.setgid(gid)
798
 
    except OSError, error:
799
 
        if error[0] != errno.EPERM:
800
 
            raise error
801
 
    
802
714
    global service
803
715
    service = AvahiService(name = server_settings["servicename"],
804
 
                           servicetype = "_mandos._tcp", )
 
716
                           type = "_mandos._tcp", );
805
717
    if server_settings["interface"]:
806
 
        service.interface = if_nametoindex\
807
 
                            (server_settings["interface"])
 
718
        service.interface = if_nametoindex(server_settings["interface"])
808
719
    
809
720
    global main_loop
810
721
    global bus
813
724
    DBusGMainLoop(set_as_default=True )
814
725
    main_loop = gobject.MainLoop()
815
726
    bus = dbus.SystemBus()
816
 
    server = dbus.Interface(bus.get_object(avahi.DBUS_NAME,
817
 
                                           avahi.DBUS_PATH_SERVER),
818
 
                            avahi.DBUS_INTERFACE_SERVER)
 
727
    server = dbus.Interface(
 
728
            bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
 
729
            avahi.DBUS_INTERFACE_SERVER )
819
730
    # End of Avahi example code
820
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()
821
743
    def remove_from_clients(client):
822
744
        clients.remove(client)
823
745
        if not clients:
829
751
                              config
830
752
                              = dict(client_config.items(section)))
831
753
                       for section in client_config.sections()))
832
 
    if not clients:
833
 
        logger.critical(u"No clients defined")
834
 
        sys.exit(1)
835
754
    
836
 
    if debug:
837
 
        # Redirect stdin so all checkers get /dev/null
838
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
839
 
        os.dup2(null, sys.stdin.fileno())
840
 
        if null > 2:
841
 
            os.close(null)
842
 
    else:
843
 
        # No console logging
844
 
        logger.removeHandler(console)
845
 
        # Close all input and output, do double fork, etc.
 
755
    if not debug:
846
756
        daemon()
847
757
    
848
 
    try:
849
 
        pid = os.getpid()
850
 
        pidfile.write(str(pid) + "\n")
851
 
        pidfile.close()
852
 
        del pidfile
853
 
    except IOError:
854
 
        logger.error(u"Could not write to file %r with PID %d",
855
 
                     pidfilename, pid)
856
 
    except NameError:
857
 
        # "pidfile" was never created
858
 
        pass
859
 
    del pidfilename
860
 
    
861
758
    def cleanup():
862
759
        "Cleanup function; run on exit"
863
760
        global group
882
779
    for client in clients:
883
780
        client.start()
884
781
    
885
 
    tcp_server.enable()
886
 
    tcp_server.server_activate()
887
 
    
 
782
    tcp_server = IPv6_TCPServer((server_settings["address"],
 
783
                                 server_settings["port"]),
 
784
                                tcp_handler,
 
785
                                settings=server_settings,
 
786
                                clients=clients)
888
787
    # Find out what port we got
889
788
    service.port = tcp_server.socket.getsockname()[1]
890
789
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
907
806
                             tcp_server.handle_request\
908
807
                             (*args[2:], **kwargs) or True)
909
808
        
910
 
        logger.debug(u"Starting main loop")
 
809
        logger.debug("Starting main loop")
 
810
        main_loop_started = True
911
811
        main_loop.run()
912
812
    except AvahiError, error:
913
813
        logger.critical(u"AvahiError: %s" + unicode(error))