113
98
class AvahiService(object):
114
"""An Avahi (Zeroconf) service.
117
100
interface: integer; avahi.IF_UNSPEC or an interface index.
118
101
Used to optionally bind to the specified interface.
119
name: string; Example: u'Mandos'
120
type: string; Example: u'_mandos._tcp'.
121
See <http://www.dns-sd.org/ServiceTypes.html>
122
port: integer; what port to announce
123
TXT: list of strings; TXT record for the service
124
domain: string; Domain to publish on, default to .local if empty.
125
host: string; Host to publish records for, default is localhost
126
max_renames: integer; maximum number of renames
127
rename_count: integer; counter so we only rename after collisions
128
a sensible number of times
129
group: D-Bus Entry Group
131
bus: dbus.SystemBus()
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
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
133
114
def __init__(self, interface = avahi.IF_UNSPEC, name = None,
134
servicetype = None, port = None, TXT = None,
135
domain = u"", host = u"", max_renames = 32768,
136
protocol = avahi.PROTO_UNSPEC, bus = None):
115
type = None, port = None, TXT = None, domain = "",
116
host = "", max_renames = 12):
117
"""An Avahi (Zeroconf) service. """
137
118
self.interface = interface
139
self.type = servicetype
141
self.TXT = TXT if TXT is not None else []
142
126
self.domain = domain
144
128
self.rename_count = 0
145
self.max_renames = max_renames
146
self.protocol = protocol
147
self.group = None # our entry group
150
129
def rename(self):
151
130
"""Derived from the Avahi example code"""
152
131
if self.rename_count >= self.max_renames:
153
logger.critical(u"No suitable Zeroconf service name found"
154
u" after %i retries, exiting.",
156
raise AvahiServiceError(u"Too many renames")
157
self.name = self.server.GetAlternativeServiceName(self.name)
158
logger.info(u"Changing Zeroconf service name to %r ...",
160
syslogger.setFormatter(logging.Formatter
161
(u'Mandos (%s) [%%(process)d]:'
162
u' %%(levelname)s: %%(message)s'
132
logger.critical(u"No suitable service name found after %i"
133
u" retries, exiting.", rename_count)
134
raise AvahiServiceError("Too many renames")
135
name = server.GetAlternativeServiceName(name)
136
logger.notice(u"Changing name to %r ...", name)
166
139
self.rename_count += 1
167
140
def remove(self):
168
141
"""Derived from the Avahi example code"""
169
if self.group is not None:
142
if group is not None:
172
145
"""Derived from the Avahi example code"""
173
if self.group is None:
174
self.group = dbus.Interface(
175
self.bus.get_object(avahi.DBUS_NAME,
176
self.server.EntryGroupNew()),
177
avahi.DBUS_INTERFACE_ENTRY_GROUP)
178
self.group.connect_to_signal('StateChanged',
180
.entry_group_state_changed)
181
logger.debug(u"Adding Zeroconf service '%s' of type '%s' ...",
182
self.name, self.type)
183
self.group.AddService(
186
dbus.UInt32(0), # flags
187
self.name, self.type,
188
self.domain, self.host,
189
dbus.UInt16(self.port),
190
avahi.string_array_to_txt_array(self.TXT))
192
def entry_group_state_changed(self, state, error):
193
"""Derived from the Avahi example code"""
194
logger.debug(u"Avahi state change: %i", state)
196
if state == avahi.ENTRY_GROUP_ESTABLISHED:
197
logger.debug(u"Zeroconf service established.")
198
elif state == avahi.ENTRY_GROUP_COLLISION:
199
logger.warning(u"Zeroconf service name collision.")
201
elif state == avahi.ENTRY_GROUP_FAILURE:
202
logger.critical(u"Avahi: Error in group state changed %s",
204
raise AvahiGroupError(u"State changed: %s"
207
"""Derived from the Avahi example code"""
208
if self.group is not None:
211
def server_state_changed(self, state):
212
"""Derived from the Avahi example code"""
213
if state == avahi.SERVER_COLLISION:
214
logger.error(u"Zeroconf server name collision")
216
elif state == avahi.SERVER_RUNNING:
219
"""Derived from the Avahi example code"""
220
if self.server is None:
221
self.server = dbus.Interface(
222
self.bus.get_object(avahi.DBUS_NAME,
223
avahi.DBUS_PATH_SERVER),
224
avahi.DBUS_INTERFACE_SERVER)
225
self.server.connect_to_signal(u"StateChanged",
226
self.server_state_changed)
227
self.server_state_changed(self.server.GetState())
148
group = dbus.Interface\
149
(bus.get_object(avahi.DBUS_NAME,
150
server.EntryGroupNew()),
151
avahi.DBUS_INTERFACE_ENTRY_GROUP)
152
group.connect_to_signal('StateChanged',
153
entry_group_state_changed)
154
logger.debug(u"Adding service '%s' of type '%s' ...",
155
service.name, service.type)
157
self.interface, # interface
158
avahi.PROTO_INET6, # protocol
159
dbus.UInt32(0), # flags
160
self.name, self.type,
161
self.domain, self.host,
162
dbus.UInt16(self.port),
163
avahi.string_array_to_txt_array(self.TXT))
166
# From the Avahi example code:
167
group = None # our entry group
168
# End of Avahi example code
230
171
class Client(object):
231
172
"""A representation of a client host served by this server.
234
name: string; from the config file, used in log messages and
174
name: string; from the config file, used in log messages
236
175
fingerprint: string (40 or 32 hexadecimal digits); used to
237
176
uniquely identify the client
238
secret: bytestring; sent verbatim (over TLS) to client
239
host: string; available for use by the checker command
240
created: datetime.datetime(); (UTC) object creation
241
last_enabled: datetime.datetime(); (UTC)
243
last_checked_ok: datetime.datetime(); (UTC) or None
244
timeout: datetime.timedelta(); How long from last_checked_ok
245
until this client is invalid
246
interval: datetime.timedelta(); How often to start a new checker
247
disable_hook: If set, called by disable() as disable_hook(self)
248
checker: subprocess.Popen(); a running checker process used
249
to see if the client lives.
250
'None' if no process is running.
177
secret: bytestring; sent verbatim (over TLS) to client
178
fqdn: string (FQDN); available for use by the checker command
179
created: datetime.datetime(); object creation, not client host
180
last_checked_ok: datetime.datetime() or None if not yet checked OK
181
timeout: datetime.timedelta(); How long from last_checked_ok
182
until this client is invalid
183
interval: datetime.timedelta(); How often to start a new checker
184
stop_hook: If set, called by stop() as stop_hook(self)
185
checker: subprocess.Popen(); a running checker process used
186
to see if the client lives.
187
'None' if no process is running.
251
188
checker_initiator_tag: a gobject event source tag, or None
252
disable_initiator_tag: - '' -
189
stop_initiator_tag: - '' -
253
190
checker_callback_tag: - '' -
254
191
checker_command: string; External command which is run to check if
255
192
client lives. %() expansions are done at
256
193
runtime with vars(self) as dict, so that for
257
194
instance %(name)s can be used in the command.
258
current_checker_command: string; current running checker_command
196
_timeout: Real variable for 'timeout'
197
_interval: Real variable for 'interval'
198
_timeout_milliseconds: Used when calling gobject.timeout_add()
199
_interval_milliseconds: - '' -
262
def _timedelta_to_milliseconds(td):
263
"Convert a datetime.timedelta() to milliseconds"
264
return ((td.days * 24 * 60 * 60 * 1000)
265
+ (td.seconds * 1000)
266
+ (td.microseconds // 1000))
268
def timeout_milliseconds(self):
269
"Return the 'timeout' attribute in milliseconds"
270
return self._timedelta_to_milliseconds(self.timeout)
272
def interval_milliseconds(self):
273
"Return the 'interval' attribute in milliseconds"
274
return self._timedelta_to_milliseconds(self.interval)
276
def __init__(self, name = None, disable_hook=None, config=None):
277
"""Note: the 'checker' key in 'config' sets the
278
'checker_command' attribute and *not* the 'checker'
201
def _set_timeout(self, timeout):
202
"Setter function for 'timeout' attribute"
203
self._timeout = timeout
204
self._timeout_milliseconds = ((self.timeout.days
205
* 24 * 60 * 60 * 1000)
206
+ (self.timeout.seconds * 1000)
207
+ (self.timeout.microseconds
209
timeout = property(lambda self: self._timeout,
212
def _set_interval(self, interval):
213
"Setter function for 'interval' attribute"
214
self._interval = interval
215
self._interval_milliseconds = ((self.interval.days
216
* 24 * 60 * 60 * 1000)
217
+ (self.interval.seconds
219
+ (self.interval.microseconds
221
interval = property(lambda self: self._interval,
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.."""
283
230
logger.debug(u"Creating client %r", self.name)
284
# Uppercase and remove spaces from fingerprint for later
285
# comparison purposes with return value from the fingerprint()
287
self.fingerprint = (config[u"fingerprint"].upper()
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"")
289
235
logger.debug(u" Fingerprint: %s", self.fingerprint)
290
if u"secret" in config:
291
self.secret = config[u"secret"].decode(u"base64")
292
elif u"secfile" in config:
293
with closing(open(os.path.expanduser
295
(config[u"secfile"])),
297
self.secret = secfile.read()
237
self.secret = secret.decode(u"base64")
240
self.secret = sf.read()
299
243
raise TypeError(u"No secret or secfile for client %s"
301
self.host = config.get(u"host", u"")
302
self.created = datetime.datetime.utcnow()
304
self.last_enabled = None
246
self.created = datetime.datetime.now()
305
247
self.last_checked_ok = None
306
self.timeout = string_to_delta(config[u"timeout"])
307
self.interval = string_to_delta(config[u"interval"])
308
self.disable_hook = disable_hook
248
self.timeout = string_to_delta(timeout)
249
self.interval = string_to_delta(interval)
250
self.stop_hook = stop_hook
309
251
self.checker = None
310
252
self.checker_initiator_tag = None
311
self.disable_initiator_tag = None
253
self.stop_initiator_tag = None
312
254
self.checker_callback_tag = None
313
self.checker_command = config[u"checker"]
314
self.current_checker_command = None
315
self.last_connect = None
255
self.check_command = checker
318
257
"""Start this client's checker and timeout hooks"""
319
if getattr(self, u"enabled", False):
322
self.last_enabled = datetime.datetime.utcnow()
323
258
# Schedule a new checker to be started an 'interval' from now,
324
259
# and every interval from then on.
325
self.checker_initiator_tag = (gobject.timeout_add
326
(self.interval_milliseconds(),
260
self.checker_initiator_tag = gobject.timeout_add\
261
(self._interval_milliseconds,
328
263
# Also start a new checker *right now*.
329
264
self.start_checker()
330
# Schedule a disable() when 'timeout' has passed
331
self.disable_initiator_tag = (gobject.timeout_add
332
(self.timeout_milliseconds(),
337
"""Disable this client."""
338
if not getattr(self, "enabled", False):
265
# Schedule a stop() when 'timeout' has passed
266
self.stop_initiator_tag = gobject.timeout_add\
267
(self._timeout_milliseconds,
271
The possibility that a client might be restarted is left open,
272
but not currently used."""
273
# If this client doesn't have a secret, it is already stopped.
275
logger.debug(u"Stopping client %s", self.name)
340
logger.info(u"Disabling client %s", self.name)
341
if getattr(self, u"disable_initiator_tag", False):
342
gobject.source_remove(self.disable_initiator_tag)
343
self.disable_initiator_tag = None
344
if getattr(self, u"checker_initiator_tag", False):
279
if getattr(self, "stop_initiator_tag", False):
280
gobject.source_remove(self.stop_initiator_tag)
281
self.stop_initiator_tag = None
282
if getattr(self, "checker_initiator_tag", False):
345
283
gobject.source_remove(self.checker_initiator_tag)
346
284
self.checker_initiator_tag = None
347
285
self.stop_checker()
348
if self.disable_hook:
349
self.disable_hook(self)
351
288
# Do not run this again if called by a gobject.timeout_add
354
290
def __del__(self):
355
self.disable_hook = None
358
def checker_callback(self, pid, condition, command):
291
self.stop_hook = None
293
def checker_callback(self, pid, condition):
359
294
"""The checker has completed, so take appropriate actions."""
295
now = datetime.datetime.now()
360
296
self.checker_callback_tag = None
361
297
self.checker = None
362
if os.WIFEXITED(condition):
363
exitstatus = os.WEXITSTATUS(condition)
365
logger.info(u"Checker for %(name)s succeeded",
369
logger.info(u"Checker for %(name)s failed",
298
if os.WIFEXITED(condition) \
299
and (os.WEXITSTATUS(condition) == 0):
300
logger.debug(u"Checker for %(name)s succeeded",
302
self.last_checked_ok = now
303
gobject.source_remove(self.stop_initiator_tag)
304
self.stop_initiator_tag = gobject.timeout_add\
305
(self._timeout_milliseconds,
307
elif not os.WIFEXITED(condition):
372
308
logger.warning(u"Checker for %(name)s crashed?",
375
def checked_ok(self):
376
"""Bump up the timeout for this client.
378
This should only be called when the client has been seen,
381
self.last_checked_ok = datetime.datetime.utcnow()
382
gobject.source_remove(self.disable_initiator_tag)
383
self.disable_initiator_tag = (gobject.timeout_add
384
(self.timeout_milliseconds(),
311
logger.debug(u"Checker for %(name)s failed",
387
313
def start_checker(self):
388
314
"""Start a new checker subprocess if one is not running.
390
315
If a checker already exists, leave it running and do
392
317
# The reason for not killing a running checker is that if we
474
368
if error.errno != errno.ESRCH: # No such process
476
370
self.checker = None
478
371
def still_valid(self):
479
372
"""Has the timeout not yet passed for this client?"""
480
if not getattr(self, u"enabled", False):
482
now = datetime.datetime.utcnow()
373
now = datetime.datetime.now()
483
374
if self.last_checked_ok is None:
484
375
return now < (self.created + self.timeout)
486
377
return now < (self.last_checked_ok + self.timeout)
489
def dbus_service_property(dbus_interface, signature=u"v",
490
access=u"readwrite", byte_arrays=False):
491
"""Decorators for marking methods of a DBusObjectWithProperties to
492
become properties on the D-Bus.
494
The decorated method will be called with no arguments by "Get"
495
and with one argument by "Set".
497
The parameters, where they are supported, are the same as
498
dbus.service.method, except there is only "signature", since the
499
type from Get() and the type sent to Set() is the same.
502
func._dbus_is_property = True
503
func._dbus_interface = dbus_interface
504
func._dbus_signature = signature
505
func._dbus_access = access
506
func._dbus_name = func.__name__
507
if func._dbus_name.endswith(u"_dbus_property"):
508
func._dbus_name = func._dbus_name[:-14]
509
func._dbus_get_args_options = {u'byte_arrays': byte_arrays }
514
class DBusPropertyException(dbus.exceptions.DBusException):
515
"""A base class for D-Bus property-related exceptions
517
def __unicode__(self):
518
return unicode(str(self))
521
class DBusPropertyAccessException(DBusPropertyException):
522
"""A property's access permissions disallows an operation.
527
class DBusPropertyNotFound(DBusPropertyException):
528
"""An attempt was made to access a non-existing property.
533
class DBusObjectWithProperties(dbus.service.Object):
534
"""A D-Bus object with properties.
536
Classes inheriting from this can use the dbus_service_property
537
decorator to expose methods as D-Bus properties. It exposes the
538
standard Get(), Set(), and GetAll() methods on the D-Bus.
542
def _is_dbus_property(obj):
543
return getattr(obj, u"_dbus_is_property", False)
545
def _get_all_dbus_properties(self):
546
"""Returns a generator of (name, attribute) pairs
548
return ((prop._dbus_name, prop)
550
inspect.getmembers(self, self._is_dbus_property))
552
def _get_dbus_property(self, interface_name, property_name):
553
"""Returns a bound method if one exists which is a D-Bus
554
property with the specified name and interface.
556
for name in (property_name,
557
property_name + u"_dbus_property"):
558
prop = getattr(self, name, None)
560
or not self._is_dbus_property(prop)
561
or prop._dbus_name != property_name
562
or (interface_name and prop._dbus_interface
563
and interface_name != prop._dbus_interface)):
567
raise DBusPropertyNotFound(self.dbus_object_path + u":"
568
+ interface_name + u"."
571
@dbus.service.method(dbus.PROPERTIES_IFACE, in_signature=u"ss",
573
def Get(self, interface_name, property_name):
574
"""Standard D-Bus property Get() method, see D-Bus standard.
576
prop = self._get_dbus_property(interface_name, property_name)
577
if prop._dbus_access == u"write":
578
raise DBusPropertyAccessException(property_name)
580
if not hasattr(value, u"variant_level"):
582
return type(value)(value, variant_level=value.variant_level+1)
584
@dbus.service.method(dbus.PROPERTIES_IFACE, in_signature=u"ssv")
585
def Set(self, interface_name, property_name, value):
586
"""Standard D-Bus property Set() method, see D-Bus standard.
588
prop = self._get_dbus_property(interface_name, property_name)
589
if prop._dbus_access == u"read":
590
raise DBusPropertyAccessException(property_name)
591
if prop._dbus_get_args_options[u"byte_arrays"]:
592
value = dbus.ByteArray(''.join(unichr(byte)
596
@dbus.service.method(dbus.PROPERTIES_IFACE, in_signature=u"s",
597
out_signature=u"a{sv}")
598
def GetAll(self, interface_name):
599
"""Standard D-Bus property GetAll() method, see D-Bus
602
Note: Will not include properties with access="write".
605
for name, prop in self._get_all_dbus_properties():
607
and interface_name != prop._dbus_interface):
608
# Interface non-empty but did not match
610
# Ignore write-only properties
611
if prop._dbus_access == u"write":
614
if not hasattr(value, u"variant_level"):
617
all[name] = type(value)(value, variant_level=
618
value.variant_level+1)
619
return dbus.Dictionary(all, signature=u"sv")
621
@dbus.service.method(dbus.INTROSPECTABLE_IFACE,
623
path_keyword='object_path',
624
connection_keyword='connection')
625
def Introspect(self, object_path, connection):
626
"""Standard D-Bus method, overloaded to insert property tags.
628
xmlstring = dbus.service.Object.Introspect(self, object_path,
630
document = xml.dom.minidom.parseString(xmlstring)
632
def make_tag(document, name, prop):
633
e = document.createElement(u"property")
634
e.setAttribute(u"name", name)
635
e.setAttribute(u"type", prop._dbus_signature)
636
e.setAttribute(u"access", prop._dbus_access)
638
for if_tag in document.getElementsByTagName(u"interface"):
639
for tag in (make_tag(document, name, prop)
641
in self._get_all_dbus_properties()
642
if prop._dbus_interface
643
== if_tag.getAttribute(u"name")):
644
if_tag.appendChild(tag)
645
# Add the names to the return values for the
646
# "org.freedesktop.DBus.Properties" methods
647
if (if_tag.getAttribute(u"name")
648
== u"org.freedesktop.DBus.Properties"):
649
for cn in if_tag.getElementsByTagName(u"method"):
650
if cn.getAttribute(u"name") == u"Get":
651
for arg in cn.getElementsByTagName(u"arg"):
652
if (arg.getAttribute(u"direction")
654
arg.setAttribute(u"name", u"value")
655
elif cn.getAttribute(u"name") == u"GetAll":
656
for arg in cn.getElementsByTagName(u"arg"):
657
if (arg.getAttribute(u"direction")
659
arg.setAttribute(u"name", u"props")
660
xmlstring = document.toxml(u"utf-8")
665
class ClientDBus(Client, DBusObjectWithProperties):
666
"""A Client class using D-Bus
669
dbus_object_path: dbus.ObjectPath
670
bus: dbus.SystemBus()
672
# dbus.service.Object doesn't use super(), so we can't either.
674
def __init__(self, bus = None, *args, **kwargs):
676
Client.__init__(self, *args, **kwargs)
677
# Only now, when this client is initialized, can it show up on
679
self.dbus_object_path = (dbus.ObjectPath
681
+ self.name.replace(u".", u"_")))
682
DBusObjectWithProperties.__init__(self, self.bus,
683
self.dbus_object_path)
686
def _datetime_to_dbus(dt, variant_level=0):
687
"""Convert a UTC datetime.datetime() to a D-Bus type."""
688
return dbus.String(dt.isoformat(),
689
variant_level=variant_level)
692
oldstate = getattr(self, u"enabled", False)
693
r = Client.enable(self)
694
if oldstate != self.enabled:
696
self.PropertyChanged(dbus.String(u"enabled"),
697
dbus.Boolean(True, variant_level=1))
698
self.PropertyChanged(
699
dbus.String(u"last_enabled"),
700
self._datetime_to_dbus(self.last_enabled,
704
def disable(self, signal = True):
705
oldstate = getattr(self, u"enabled", False)
706
r = Client.disable(self)
707
if signal and oldstate != self.enabled:
709
self.PropertyChanged(dbus.String(u"enabled"),
710
dbus.Boolean(False, variant_level=1))
713
def __del__(self, *args, **kwargs):
715
self.remove_from_connection()
718
if hasattr(DBusObjectWithProperties, u"__del__"):
719
DBusObjectWithProperties.__del__(self, *args, **kwargs)
720
Client.__del__(self, *args, **kwargs)
722
def checker_callback(self, pid, condition, command,
724
self.checker_callback_tag = None
727
self.PropertyChanged(dbus.String(u"checker_running"),
728
dbus.Boolean(False, variant_level=1))
729
if os.WIFEXITED(condition):
730
exitstatus = os.WEXITSTATUS(condition)
732
self.CheckerCompleted(dbus.Int16(exitstatus),
733
dbus.Int64(condition),
734
dbus.String(command))
737
self.CheckerCompleted(dbus.Int16(-1),
738
dbus.Int64(condition),
739
dbus.String(command))
741
return Client.checker_callback(self, pid, condition, command,
744
def checked_ok(self, *args, **kwargs):
745
r = Client.checked_ok(self, *args, **kwargs)
747
self.PropertyChanged(
748
dbus.String(u"last_checked_ok"),
749
(self._datetime_to_dbus(self.last_checked_ok,
753
def start_checker(self, *args, **kwargs):
754
old_checker = self.checker
755
if self.checker is not None:
756
old_checker_pid = self.checker.pid
758
old_checker_pid = None
759
r = Client.start_checker(self, *args, **kwargs)
760
# Only if new checker process was started
761
if (self.checker is not None
762
and old_checker_pid != self.checker.pid):
764
self.CheckerStarted(self.current_checker_command)
765
self.PropertyChanged(
766
dbus.String(u"checker_running"),
767
dbus.Boolean(True, variant_level=1))
770
def stop_checker(self, *args, **kwargs):
771
old_checker = getattr(self, u"checker", None)
772
r = Client.stop_checker(self, *args, **kwargs)
773
if (old_checker is not None
774
and getattr(self, u"checker", None) is None):
775
self.PropertyChanged(dbus.String(u"checker_running"),
776
dbus.Boolean(False, variant_level=1))
779
## D-Bus methods & signals
780
_interface = u"se.bsnet.fukt.Mandos.Client"
783
@dbus.service.method(_interface)
785
return self.checked_ok()
787
# CheckerCompleted - signal
788
@dbus.service.signal(_interface, signature=u"nxs")
789
def CheckerCompleted(self, exitcode, waitstatus, command):
793
# CheckerStarted - signal
794
@dbus.service.signal(_interface, signature=u"s")
795
def CheckerStarted(self, command):
799
# PropertyChanged - signal
800
@dbus.service.signal(_interface, signature=u"sv")
801
def PropertyChanged(self, property, value):
805
# ReceivedSecret - signal
806
@dbus.service.signal(_interface)
807
def ReceivedSecret(self):
812
@dbus.service.signal(_interface)
818
@dbus.service.method(_interface)
823
# StartChecker - method
824
@dbus.service.method(_interface)
825
def StartChecker(self):
830
@dbus.service.method(_interface)
835
# StopChecker - method
836
@dbus.service.method(_interface)
837
def StopChecker(self):
841
@dbus_service_property(_interface, signature=u"s", access=u"read")
842
def name_dbus_property(self):
843
return dbus.String(self.name)
845
# fingerprint - property
846
@dbus_service_property(_interface, signature=u"s", access=u"read")
847
def fingerprint_dbus_property(self):
848
return dbus.String(self.fingerprint)
851
@dbus_service_property(_interface, signature=u"s",
853
def host_dbus_property(self, value=None):
854
if value is None: # get
855
return dbus.String(self.host)
858
self.PropertyChanged(dbus.String(u"host"),
859
dbus.String(value, variant_level=1))
862
@dbus_service_property(_interface, signature=u"s", access=u"read")
863
def created_dbus_property(self):
864
return dbus.String(self._datetime_to_dbus(self.created))
866
# last_enabled - property
867
@dbus_service_property(_interface, signature=u"s", access=u"read")
868
def last_enabled_dbus_property(self):
869
if self.last_enabled is None:
870
return dbus.String(u"")
871
return dbus.String(self._datetime_to_dbus(self.last_enabled))
874
@dbus_service_property(_interface, signature=u"b",
876
def enabled_dbus_property(self, value=None):
877
if value is None: # get
878
return dbus.Boolean(self.enabled)
884
# last_checked_ok - property
885
@dbus_service_property(_interface, signature=u"s",
887
def last_checked_ok_dbus_property(self, value=None):
888
if value is not None:
891
if self.last_checked_ok is None:
892
return dbus.String(u"")
893
return dbus.String(self._datetime_to_dbus(self
897
@dbus_service_property(_interface, signature=u"t",
899
def timeout_dbus_property(self, value=None):
900
if value is None: # get
901
return dbus.UInt64(self.timeout_milliseconds())
902
self.timeout = datetime.timedelta(0, 0, 0, value)
904
self.PropertyChanged(dbus.String(u"timeout"),
905
dbus.UInt64(value, variant_level=1))
906
if getattr(self, u"disable_initiator_tag", None) is None:
909
gobject.source_remove(self.disable_initiator_tag)
910
self.disable_initiator_tag = None
912
_timedelta_to_milliseconds((self
918
# The timeout has passed
921
self.disable_initiator_tag = (gobject.timeout_add
922
(time_to_die, self.disable))
924
# interval - property
925
@dbus_service_property(_interface, signature=u"t",
927
def interval_dbus_property(self, value=None):
928
if value is None: # get
929
return dbus.UInt64(self.interval_milliseconds())
930
self.interval = datetime.timedelta(0, 0, 0, value)
932
self.PropertyChanged(dbus.String(u"interval"),
933
dbus.UInt64(value, variant_level=1))
934
if getattr(self, u"checker_initiator_tag", None) is None:
936
# Reschedule checker run
937
gobject.source_remove(self.checker_initiator_tag)
938
self.checker_initiator_tag = (gobject.timeout_add
939
(value, self.start_checker))
940
self.start_checker() # Start one now, too
943
@dbus_service_property(_interface, signature=u"s",
945
def checker_dbus_property(self, value=None):
946
if value is None: # get
947
return dbus.String(self.checker_command)
948
self.checker_command = value
950
self.PropertyChanged(dbus.String(u"checker"),
951
dbus.String(self.checker_command,
954
# checker_running - property
955
@dbus_service_property(_interface, signature=u"b",
957
def checker_running_dbus_property(self, value=None):
958
if value is None: # get
959
return dbus.Boolean(self.checker is not None)
965
# object_path - property
966
@dbus_service_property(_interface, signature=u"o", access=u"read")
967
def object_path_dbus_property(self):
968
return self.dbus_object_path # is already a dbus.ObjectPath
971
@dbus_service_property(_interface, signature=u"ay",
972
access=u"write", byte_arrays=True)
973
def secret_dbus_property(self, value):
974
self.secret = str(value)
979
class ClientHandler(socketserver.BaseRequestHandler, object):
980
"""A class to handle client connections.
982
Instantiated once for each connection to handle it.
380
def peer_certificate(session):
381
"Return the peer's OpenPGP certificate as a bytestring"
382
# If not an OpenPGP certificate...
383
if gnutls.library.functions.gnutls_certificate_type_get\
384
(session._c_object) \
385
!= gnutls.library.constants.GNUTLS_CRT_OPENPGP:
386
# ...do the normal thing
387
return session.peer_certificate
388
list_size = ctypes.c_uint()
389
cert_list = gnutls.library.functions.gnutls_certificate_get_peers\
390
(session._c_object, ctypes.byref(list_size))
391
if list_size.value == 0:
394
return ctypes.string_at(cert.data, cert.size)
397
def fingerprint(openpgp):
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\
403
# New GnuTLS "datum" with the OpenPGP public key
404
datum = gnutls.library.types.gnutls_datum_t\
405
(ctypes.cast(ctypes.c_char_p(openpgp),
406
ctypes.POINTER(ctypes.c_ubyte)),
407
ctypes.c_uint(len(openpgp)))
408
# Import the OpenPGP public key into the certificate
409
ret = gnutls.library.functions.gnutls_openpgp_crt_import\
412
gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
413
# New buffer for the fingerprint
414
buffer = ctypes.create_string_buffer(20)
415
buffer_length = ctypes.c_size_t()
416
# Get the fingerprint from the certificate into the buffer
417
gnutls.library.functions.gnutls_openpgp_crt_get_fingerprint\
418
(crt, ctypes.byref(buffer), ctypes.byref(buffer_length))
419
# Deinit the certificate
420
gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
421
# Convert the buffer to a Python bytestring
422
fpr = ctypes.string_at(buffer, buffer_length.value)
423
# Convert the bytestring to hexadecimal notation
424
hex_fpr = u''.join(u"%02X" % ord(char) for char in fpr)
428
class tcp_handler(SocketServer.BaseRequestHandler, object):
429
"""A TCP request handler class.
430
Instantiated by IPv6_TCPServer for each request to handle it.
983
431
Note: This will run in its own forked process."""
985
433
def handle(self):
986
logger.info(u"TCP connection from: %s",
987
unicode(self.client_address))
988
logger.debug(u"IPC Pipe FD: %d", self.server.pipe[1])
989
# Open IPC pipe to parent process
990
with closing(os.fdopen(self.server.pipe[1], u"w", 1)) as ipc:
991
session = (gnutls.connection
992
.ClientSession(self.request,
996
line = self.request.makefile().readline()
997
logger.debug(u"Protocol version: %r", line)
999
if int(line.strip().split()[0]) > 1:
1001
except (ValueError, IndexError, RuntimeError), error:
1002
logger.error(u"Unknown protocol version: %s", error)
1005
# Note: gnutls.connection.X509Credentials is really a
1006
# generic GnuTLS certificate credentials object so long as
1007
# no X.509 keys are added to it. Therefore, we can use it
1008
# here despite using OpenPGP certificates.
1010
#priority = u':'.join((u"NONE", u"+VERS-TLS1.1",
1011
# u"+AES-256-CBC", u"+SHA1",
1012
# u"+COMP-NULL", u"+CTYPE-OPENPGP",
1014
# Use a fallback default, since this MUST be set.
1015
priority = self.server.gnutls_priority
1016
if priority is None:
1017
priority = u"NORMAL"
1018
(gnutls.library.functions
1019
.gnutls_priority_set_direct(session._c_object,
1024
except gnutls.errors.GNUTLSError, error:
1025
logger.warning(u"Handshake failed: %s", error)
1026
# Do not run session.bye() here: the session is not
1027
# established. Just abandon the request.
1029
logger.debug(u"Handshake succeeded")
1031
fpr = self.fingerprint(self.peer_certificate(session))
1032
except (TypeError, gnutls.errors.GNUTLSError), error:
1033
logger.warning(u"Bad certificate: %s", error)
1036
logger.debug(u"Fingerprint: %s", fpr)
1038
for c in self.server.clients:
1039
if c.fingerprint == fpr:
1043
ipc.write(u"NOTFOUND %s %s\n"
1044
% (fpr, unicode(self.client_address)))
1047
# Have to check if client.still_valid(), since it is
1048
# possible that the client timed out while establishing
1049
# the GnuTLS session.
1050
if not client.still_valid():
1051
ipc.write(u"INVALID %s\n" % client.name)
1054
ipc.write(u"SENDING %s\n" % client.name)
1056
while sent_size < len(client.secret):
1057
sent = session.send(client.secret[sent_size:])
1058
logger.debug(u"Sent: %d, remaining: %d",
1059
sent, len(client.secret)
1060
- (sent_size + sent))
1065
def peer_certificate(session):
1066
"Return the peer's OpenPGP certificate as a bytestring"
1067
# If not an OpenPGP certificate...
1068
if (gnutls.library.functions
1069
.gnutls_certificate_type_get(session._c_object)
1070
!= gnutls.library.constants.GNUTLS_CRT_OPENPGP):
1071
# ...do the normal thing
1072
return session.peer_certificate
1073
list_size = ctypes.c_uint(1)
1074
cert_list = (gnutls.library.functions
1075
.gnutls_certificate_get_peers
1076
(session._c_object, ctypes.byref(list_size)))
1077
if not bool(cert_list) and list_size.value != 0:
1078
raise gnutls.errors.GNUTLSError(u"error getting peer"
1080
if list_size.value == 0:
1083
return ctypes.string_at(cert.data, cert.size)
1086
def fingerprint(openpgp):
1087
"Convert an OpenPGP bytestring to a hexdigit fingerprint"
1088
# New GnuTLS "datum" with the OpenPGP public key
1089
datum = (gnutls.library.types
1090
.gnutls_datum_t(ctypes.cast(ctypes.c_char_p(openpgp),
1093
ctypes.c_uint(len(openpgp))))
1094
# New empty GnuTLS certificate
1095
crt = gnutls.library.types.gnutls_openpgp_crt_t()
1096
(gnutls.library.functions
1097
.gnutls_openpgp_crt_init(ctypes.byref(crt)))
1098
# Import the OpenPGP public key into the certificate
1099
(gnutls.library.functions
1100
.gnutls_openpgp_crt_import(crt, ctypes.byref(datum),
1101
gnutls.library.constants
1102
.GNUTLS_OPENPGP_FMT_RAW))
1103
# Verify the self signature in the key
1104
crtverify = ctypes.c_uint()
1105
(gnutls.library.functions
1106
.gnutls_openpgp_crt_verify_self(crt, 0,
1107
ctypes.byref(crtverify)))
1108
if crtverify.value != 0:
1109
gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
1110
raise (gnutls.errors.CertificateSecurityError
1112
# New buffer for the fingerprint
1113
buf = ctypes.create_string_buffer(20)
1114
buf_len = ctypes.c_size_t()
1115
# Get the fingerprint from the certificate into the buffer
1116
(gnutls.library.functions
1117
.gnutls_openpgp_crt_get_fingerprint(crt, ctypes.byref(buf),
1118
ctypes.byref(buf_len)))
1119
# Deinit the certificate
1120
gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
1121
# Convert the buffer to a Python bytestring
1122
fpr = ctypes.string_at(buf, buf_len.value)
1123
# Convert the bytestring to hexadecimal notation
1124
hex_fpr = u''.join(u"%02X" % ord(char) for char in fpr)
1128
class ForkingMixInWithPipe(socketserver.ForkingMixIn, object):
1129
"""Like socketserver.ForkingMixIn, but also pass a pipe."""
1130
def process_request(self, request, client_address):
1131
"""Overrides and wraps the original process_request().
1133
This function creates a new pipe in self.pipe
1135
self.pipe = os.pipe()
1136
super(ForkingMixInWithPipe,
1137
self).process_request(request, client_address)
1138
os.close(self.pipe[1]) # close write end
1139
self.add_pipe(self.pipe[0])
1140
def add_pipe(self, pipe):
1141
"""Dummy function; override as necessary"""
1145
class IPv6_TCPServer(ForkingMixInWithPipe,
1146
socketserver.TCPServer, object):
1147
"""IPv6-capable TCP server. Accepts 'None' as address and/or port
434
logger.debug(u"TCP connection from: %s",
435
unicode(self.client_address))
436
session = gnutls.connection.ClientSession\
437
(self.request, gnutls.connection.X509Credentials())
438
# Note: gnutls.connection.X509Credentials is really a generic
439
# GnuTLS certificate credentials object so long as no X.509
440
# keys are added to it. Therefore, we can use it here despite
441
# using OpenPGP certificates.
443
#priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
444
# "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
446
priority = "NORMAL" # Fallback default, since this
448
if self.server.settings["priority"]:
449
priority = self.server.settings["priority"]
450
gnutls.library.functions.gnutls_priority_set_direct\
451
(session._c_object, priority, None);
455
except gnutls.errors.GNUTLSError, error:
456
logger.debug(u"Handshake failed: %s", error)
457
# Do not run session.bye() here: the session is not
458
# established. Just abandon the request.
461
fpr = fingerprint(peer_certificate(session))
462
except (TypeError, gnutls.errors.GNUTLSError), error:
463
logger.debug(u"Bad certificate: %s", error)
466
logger.debug(u"Fingerprint: %s", fpr)
468
for c in self.server.clients:
469
if c.fingerprint == fpr:
473
logger.debug(u"Client not found for fingerprint: %s", fpr)
476
# Have to check if client.still_valid(), since it is possible
477
# that the client timed out while establishing the GnuTLS
479
if not client.still_valid():
480
logger.debug(u"Client %(name)s is invalid", vars(client))
484
while sent_size < len(client.secret):
485
sent = session.send(client.secret[sent_size:])
486
logger.debug(u"Sent: %d, remaining: %d",
487
sent, len(client.secret)
488
- (sent_size + sent))
493
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
494
"""IPv6 TCP server. Accepts 'None' as address and/or port.
1150
enabled: Boolean; whether this server is activated yet
1151
interface: None or a network interface name (string)
1152
use_ipv6: Boolean; to use IPv6 or not
496
settings: Server settings
497
clients: Set() of Client objects
1154
def __init__(self, server_address, RequestHandlerClass,
1155
interface=None, use_ipv6=True):
1156
self.interface = interface
1158
self.address_family = socket.AF_INET6
1159
socketserver.TCPServer.__init__(self, server_address,
1160
RequestHandlerClass)
499
address_family = socket.AF_INET6
500
def __init__(self, *args, **kwargs):
501
if "settings" in kwargs:
502
self.settings = kwargs["settings"]
503
del kwargs["settings"]
504
if "clients" in kwargs:
505
self.clients = kwargs["clients"]
506
del kwargs["clients"]
507
return super(type(self), self).__init__(*args, **kwargs)
1161
508
def server_bind(self):
1162
509
"""This overrides the normal server_bind() function
1163
510
to bind to an interface if one was specified, and also NOT to
1164
511
bind to an address or port if they were not specified."""
1165
if self.interface is not None:
1166
if SO_BINDTODEVICE is None:
1167
logger.error(u"SO_BINDTODEVICE does not exist;"
1168
u" cannot bind to interface %s",
1172
self.socket.setsockopt(socket.SOL_SOCKET,
1176
except socket.error, error:
1177
if error[0] == errno.EPERM:
1178
logger.error(u"No permission to"
1179
u" bind to interface %s",
1181
elif error[0] == errno.ENOPROTOOPT:
1182
logger.error(u"SO_BINDTODEVICE not available;"
1183
u" cannot bind to interface %s",
512
if self.settings["interface"]:
513
# 25 is from /usr/include/asm-i486/socket.h
514
SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
516
self.socket.setsockopt(socket.SOL_SOCKET,
518
self.settings["interface"])
519
except socket.error, error:
520
if error[0] == errno.EPERM:
521
logger.warning(u"No permission to"
522
u" bind to interface %s",
523
self.settings["interface"])
1187
526
# Only bind(2) the socket if we really need to.
1188
527
if self.server_address[0] or self.server_address[1]:
1189
528
if not self.server_address[0]:
1190
if self.address_family == socket.AF_INET6:
1191
any_address = u"::" # in6addr_any
1193
any_address = socket.INADDR_ANY
1194
self.server_address = (any_address,
530
self.server_address = (in6addr_any,
1195
531
self.server_address[1])
1196
elif not self.server_address[1]:
532
elif self.server_address[1] is None:
1197
533
self.server_address = (self.server_address[0],
1199
# if self.interface:
1200
# self.server_address = (self.server_address[0],
1205
return socketserver.TCPServer.server_bind(self)
1208
class MandosServer(IPv6_TCPServer):
1212
clients: set of Client objects
1213
gnutls_priority GnuTLS priority string
1214
use_dbus: Boolean; to emit D-Bus signals or not
1216
Assumes a gobject.MainLoop event loop.
1218
def __init__(self, server_address, RequestHandlerClass,
1219
interface=None, use_ipv6=True, clients=None,
1220
gnutls_priority=None, use_dbus=True):
1221
self.enabled = False
1222
self.clients = clients
1223
if self.clients is None:
1224
self.clients = set()
1225
self.use_dbus = use_dbus
1226
self.gnutls_priority = gnutls_priority
1227
IPv6_TCPServer.__init__(self, server_address,
1228
RequestHandlerClass,
1229
interface = interface,
1230
use_ipv6 = use_ipv6)
1231
def server_activate(self):
1233
return socketserver.TCPServer.server_activate(self)
1236
def add_pipe(self, pipe):
1237
# Call "handle_ipc" for both data and EOF events
1238
gobject.io_add_watch(pipe, gobject.IO_IN | gobject.IO_HUP,
1240
def handle_ipc(self, source, condition, file_objects={}):
1242
gobject.IO_IN: u"IN", # There is data to read.
1243
gobject.IO_OUT: u"OUT", # Data can be written (without
1245
gobject.IO_PRI: u"PRI", # There is urgent data to read.
1246
gobject.IO_ERR: u"ERR", # Error condition.
1247
gobject.IO_HUP: u"HUP" # Hung up (the connection has been
1248
# broken, usually for pipes and
1251
conditions_string = ' | '.join(name
1253
condition_names.iteritems()
1254
if cond & condition)
1255
logger.debug(u"Handling IPC: FD = %d, condition = %s", source,
1258
# Turn the pipe file descriptor into a Python file object
1259
if source not in file_objects:
1260
file_objects[source] = os.fdopen(source, u"r", 1)
1262
# Read a line from the file object
1263
cmdline = file_objects[source].readline()
1264
if not cmdline: # Empty line means end of file
1265
# close the IPC pipe
1266
file_objects[source].close()
1267
del file_objects[source]
1269
# Stop calling this function
1272
logger.debug(u"IPC command: %r", cmdline)
1274
# Parse and act on command
1275
cmd, args = cmdline.rstrip(u"\r\n").split(None, 1)
1277
if cmd == u"NOTFOUND":
1278
logger.warning(u"Client not found for fingerprint: %s",
1282
mandos_dbus_service.ClientNotFound(args)
1283
elif cmd == u"INVALID":
1284
for client in self.clients:
1285
if client.name == args:
1286
logger.warning(u"Client %s is invalid", args)
1292
logger.error(u"Unknown client %s is invalid", args)
1293
elif cmd == u"SENDING":
1294
for client in self.clients:
1295
if client.name == args:
1296
logger.info(u"Sending secret to %s", client.name)
1300
client.ReceivedSecret()
1303
logger.error(u"Sending secret to unknown client %s",
1306
logger.error(u"Unknown IPC command: %r", cmdline)
1308
# Keep calling this function
535
return super(type(self), self).server_bind()
1312
538
def string_to_delta(interval):
1313
539
"""Parse a string and return a datetime.timedelta
1315
>>> string_to_delta(u'7d')
541
>>> string_to_delta('7d')
1316
542
datetime.timedelta(7)
1317
>>> string_to_delta(u'60s')
543
>>> string_to_delta('60s')
1318
544
datetime.timedelta(0, 60)
1319
>>> string_to_delta(u'60m')
545
>>> string_to_delta('60m')
1320
546
datetime.timedelta(0, 3600)
1321
>>> string_to_delta(u'24h')
547
>>> string_to_delta('24h')
1322
548
datetime.timedelta(1)
1323
549
>>> string_to_delta(u'1w')
1324
550
datetime.timedelta(7)
1325
>>> string_to_delta(u'5m 30s')
1326
datetime.timedelta(0, 330)
1328
timevalue = datetime.timedelta(0)
1329
for s in interval.split():
1331
suffix = unicode(s[-1])
1334
delta = datetime.timedelta(value)
1335
elif suffix == u"s":
1336
delta = datetime.timedelta(0, value)
1337
elif suffix == u"m":
1338
delta = datetime.timedelta(0, 0, 0, 0, value)
1339
elif suffix == u"h":
1340
delta = datetime.timedelta(0, 0, 0, 0, 0, value)
1341
elif suffix == u"w":
1342
delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
1345
except (ValueError, IndexError):
553
suffix=unicode(interval[-1])
554
value=int(interval[:-1])
556
delta = datetime.timedelta(value)
558
delta = datetime.timedelta(0, value)
560
delta = datetime.timedelta(0, 0, 0, 0, value)
562
delta = datetime.timedelta(0, 0, 0, 0, 0, value)
564
delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
1346
566
raise ValueError
1351
def if_nametoindex(interface):
1352
"""Call the C function if_nametoindex(), or equivalent
567
except (ValueError, IndexError):
572
def server_state_changed(state):
573
"""Derived from the Avahi example code"""
574
if state == avahi.SERVER_COLLISION:
575
logger.warning(u"Server name collision")
577
elif state == avahi.SERVER_RUNNING:
581
def entry_group_state_changed(state, error):
582
"""Derived from the Avahi example code"""
583
logger.debug(u"state change: %i", state)
1354
Note: This function cannot accept a unicode string."""
1355
global if_nametoindex
585
if state == avahi.ENTRY_GROUP_ESTABLISHED:
586
logger.debug(u"Service established.")
587
elif state == avahi.ENTRY_GROUP_COLLISION:
588
logger.warning(u"Service name collision.")
590
elif state == avahi.ENTRY_GROUP_FAILURE:
591
logger.critical(u"Error in group state changed %s",
593
raise AvahiGroupError("State changed: %s", str(error))
595
def if_nametoindex(interface, _func=[None]):
596
"""Call the C function if_nametoindex(), or equivalent"""
597
if _func[0] is not None:
598
return _func[0](interface)
1357
if_nametoindex = (ctypes.cdll.LoadLibrary
1358
(ctypes.util.find_library(u"c"))
600
if "ctypes.util" not in sys.modules:
604
libc = ctypes.cdll.LoadLibrary\
605
(ctypes.util.find_library("c"))
606
_func[0] = libc.if_nametoindex
607
return _func[0](interface)
1360
611
except (OSError, AttributeError):
1361
logger.warning(u"Doing if_nametoindex the hard way")
1362
def if_nametoindex(interface):
612
if "struct" not in sys.modules:
614
if "fcntl" not in sys.modules:
616
def the_hard_way(interface):
1363
617
"Get an interface index the hard way, i.e. using fcntl()"
1364
618
SIOCGIFINDEX = 0x8933 # From /usr/include/linux/sockios.h
1365
with closing(socket.socket()) as s:
1366
ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
1367
struct.pack(str(u"16s16x"),
1369
interface_index = struct.unpack(str(u"I"),
620
ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
621
struct.pack("16s16x", interface))
623
interface_index = struct.unpack("I", ifreq[16:20])[0]
1371
624
return interface_index
1372
return if_nametoindex(interface)
1375
def daemon(nochdir = False, noclose = False):
625
_func[0] = the_hard_way
626
return _func[0](interface)
629
def daemon(nochdir, noclose):
1376
630
"""See daemon(3). Standard BSD Unix function.
1378
631
This should really exist as os.daemon, but it doesn't (yet)."""
1387
638
# Close all standard open file descriptors
1388
639
null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
1389
640
if not stat.S_ISCHR(os.fstat(null).st_mode):
1390
641
raise OSError(errno.ENODEV,
1391
u"/dev/null not a character device")
642
"/dev/null not a character device")
1392
643
os.dup2(null, sys.stdin.fileno())
1393
644
os.dup2(null, sys.stdout.fileno())
1394
645
os.dup2(null, sys.stderr.fileno())