19
22
from sets import Set
28
from dbus.mainloop.glib import DBusGMainLoop
32
import logging.handlers
34
# logghandler.setFormatter(logging.Formatter('%(levelname)s %(message)s')
36
logger = logging.Logger('mandos')
37
logger.addHandler(logging.handlers.SysLogHandler(facility = logging.handlers.SysLogHandler.LOG_DAEMON))
39
# This variable is used to optionally bind to a specified interface.
40
# It is a global variable to fit in with the other variables from the
41
# Avahi server example code.
42
serviceInterface = avahi.IF_UNSPEC
43
# From the Avahi server example code:
44
serviceName = "Mandos"
45
serviceType = "_mandos._tcp" # http://www.dns-sd.org/ServiceTypes.html
46
servicePort = None # Not known at startup
47
serviceTXT = [] # TXT record for the service
48
domain = "" # Domain to publish on, default to .local
49
host = "" # Host to publish records for, default to localhost
50
group = None #our entry group
51
rename_count = 12 # Counter so we only rename after collisions a
52
# sensible number of times
53
# End of Avahi example code
22
56
class Client(object):
23
def __init__(self, name=None, options=None, dn=None,
24
password=None, passfile=None, fqdn=None,
25
timeout=None, interval=-1):
57
"""A representation of a client host served by this server.
59
name: string; from the config file, used in log messages
60
fingerprint: string (40 or 32 hexadecimal digits); used to
61
uniquely identify the client
62
secret: bytestring; sent verbatim (over TLS) to client
63
fqdn: string (FQDN); available for use by the checker command
64
created: datetime.datetime()
65
last_seen: datetime.datetime() or None if not yet seen
66
timeout: datetime.timedelta(); How long from last_seen until
67
this client is invalid
68
interval: datetime.timedelta(); How often to start a new checker
69
stop_hook: If set, called by stop() as stop_hook(self)
70
checker: subprocess.Popen(); a running checker process used
71
to see if the client lives.
72
Is None if no process is running.
73
checker_initiator_tag: a gobject event source tag, or None
74
stop_initiator_tag: - '' -
75
checker_callback_tag: - '' -
76
checker_command: string; External command which is run to check if
77
client lives. %()s expansions are done at
78
runtime with vars(self) as dict, so that for
79
instance %(name)s can be used in the command.
81
_timeout: Real variable for 'timeout'
82
_interval: Real variable for 'interval'
83
_timeout_milliseconds: Used by gobject.timeout_add()
84
_interval_milliseconds: - '' -
86
def _set_timeout(self, timeout):
87
"Setter function for 'timeout' attribute"
88
self._timeout = timeout
89
self._timeout_milliseconds = ((self.timeout.days
90
* 24 * 60 * 60 * 1000)
91
+ (self.timeout.seconds * 1000)
92
+ (self.timeout.microseconds
94
timeout = property(lambda self: self._timeout,
97
def _set_interval(self, interval):
98
"Setter function for 'interval' attribute"
99
self._interval = interval
100
self._interval_milliseconds = ((self.interval.days
101
* 24 * 60 * 60 * 1000)
102
+ (self.interval.seconds
104
+ (self.interval.microseconds
106
interval = property(lambda self: self._interval,
109
def __init__(self, name=None, options=None, stop_hook=None,
110
fingerprint=None, secret=None, secfile=None, fqdn=None,
111
timeout=None, interval=-1, checker=None):
29
self.password = password
31
self.password = open(passfile).readall()
113
# Uppercase and remove spaces from fingerprint
114
# for later comparison purposes with return value of
115
# the fingerprint() function
116
self.fingerprint = fingerprint.upper().replace(u" ", u"")
118
self.secret = secret.decode(u"base64")
121
self.secret = sf.read()
33
print "No Password or Passfile in client config file"
34
# raise RuntimeError XXX
35
self.password = "gazonk"
124
raise RuntimeError(u"No secret or secfile for client %s"
36
126
self.fqdn = fqdn # string
37
127
self.created = datetime.datetime.now()
38
self.last_seen = None # datetime.datetime()
128
self.last_seen = None
39
129
if timeout is None:
40
130
timeout = options.timeout
41
self.timeout = timeout # datetime.timedelta()
131
self.timeout = timeout
42
132
if interval == -1:
43
133
interval = options.interval
45
135
interval = string_to_delta(interval)
46
self.interval = interval # datetime.timedelta()
47
self.next_check = datetime.datetime.now() # datetime.datetime()
48
# Note: next_check may be in the past if checker is not None
49
self.checker = None # or a subprocess.Popen()
50
def check_action(self):
51
"""The checker said something and might have completed.
52
Check if is has, and take appropriate actions."""
53
if self.checker.poll() is None:
54
# False alarm, no result yet
56
#print "Checker for %(name)s said nothing?" % vars(self)
136
self.interval = interval
137
self.stop_hook = stop_hook
139
self.checker_initiator_tag = None
140
self.stop_initiator_tag = None
141
self.checker_callback_tag = None
142
self.check_command = checker
144
"""Start this clients checker and timeout hooks"""
145
# Schedule a new checker to be started an 'interval' from now,
146
# and every interval from then on.
147
self.checker_initiator_tag = gobject.timeout_add\
148
(self._interval_milliseconds,
150
# Also start a new checker *right now*.
152
# Schedule a stop() when 'timeout' has passed
153
self.stop_initiator_tag = gobject.timeout_add\
154
(self._timeout_milliseconds,
158
The possibility that this client might be restarted is left
159
open, but not currently used."""
160
logger.debug(u"Stopping client %s", self.name)
162
if self.stop_initiator_tag:
163
gobject.source_remove(self.stop_initiator_tag)
164
self.stop_initiator_tag = None
165
if self.checker_initiator_tag:
166
gobject.source_remove(self.checker_initiator_tag)
167
self.checker_initiator_tag = None
171
# Do not run this again if called by a gobject.timeout_add
174
# Some code duplication here and in stop()
175
if hasattr(self, "stop_initiator_tag") \
176
and self.stop_initiator_tag:
177
gobject.source_remove(self.stop_initiator_tag)
178
self.stop_initiator_tag = None
179
if hasattr(self, "checker_initiator_tag") \
180
and self.checker_initiator_tag:
181
gobject.source_remove(self.checker_initiator_tag)
182
self.checker_initiator_tag = None
184
def checker_callback(self, pid, condition):
185
"""The checker has completed, so take appropriate actions."""
58
186
now = datetime.datetime.now()
59
if self.checker.returncode == 0:
60
print "Checker for %(name)s succeeded" % vars(self)
187
if os.WIFEXITED(condition) \
188
and (os.WEXITSTATUS(condition) == 0):
189
logger.debug(u"Checker for %(name)s succeeded",
61
191
self.last_seen = now
192
gobject.source_remove(self.stop_initiator_tag)
193
self.stop_initiator_tag = gobject.timeout_add\
194
(self._timeout_milliseconds,
196
if not os.WIFEXITED(condition):
197
logger.warning(u"Checker for %(name)s crashed?",
63
print "Checker for %(name)s failed" % vars(self)
64
while self.next_check <= now:
65
self.next_check += self.interval
67
handle_request = check_action
200
logger.debug(u"Checker for %(name)s failed",
203
self.checker_callback_tag = None
68
204
def start_checker(self):
71
self.checker = subprocess.Popen("sleep 10; fping -q -- %s"
72
% re.escape(self.fqdn),
73
stdout=subprocess.PIPE,
76
except subprocess.OSError, e:
77
print "Failed to start subprocess:", e
205
"""Start a new checker subprocess if one is not running.
206
If a checker already exists, leave it running and do
208
if self.checker is None:
209
logger.debug(u"Starting checker for %s",
212
command = self.check_command % self.fqdn
214
escaped_attrs = dict((key, re.escape(str(val)))
216
vars(self).iteritems())
218
command = self.check_command % escaped_attrs
219
except TypeError, error:
220
logger.critical(u'Could not format string "%s": %s',
221
self.check_command, error)
222
return True # Try again later
224
self.checker = subprocess.\
226
stdout=subprocess.PIPE,
227
close_fds=True, shell=True,
229
self.checker_callback_tag = gobject.\
230
child_watch_add(self.checker.pid,
233
except subprocess.OSError, error:
234
logger.error(u"Failed to start subprocess: %s",
236
# Re-run this periodically if run by gobject.timeout_add
78
238
def stop_checker(self):
79
if self.checker is None:
239
"""Force the checker process, if any, to stop."""
240
if not hasattr(self, "checker") or self.checker is None:
242
gobject.source_remove(self.checker_callback_tag)
243
self.checker_callback_tag = None
81
244
os.kill(self.checker.pid, signal.SIGTERM)
82
245
if self.checker.poll() is None:
83
246
os.kill(self.checker.pid, signal.SIGKILL)
84
247
self.checker = None
85
__del__ = stop_checker
87
if self.checker is None:
89
return self.checker.stdout.fileno()
91
"""The time when something must be done about this client
92
May be in the past."""
93
if self.last_seen is None:
94
# This client has never been seen
95
next_timeout = self.created + self.timeout
97
next_timeout = self.last_seen + self.timeout
98
if self.checker is None:
99
return min(next_timeout, self.next_check)
102
248
def still_valid(self, now=None):
103
"""Has this client's timeout not passed?"""
249
"""Has the timeout not yet passed for this client?"""
105
251
now = datetime.datetime.now()
106
252
if self.last_seen is None:
107
253
return now < (self.created + self.timeout)
109
255
return now < (self.last_seen + self.timeout)
110
def it_is_time_to_check(self, now=None):
112
now = datetime.datetime.now()
113
return self.next_check <= now
116
class server_metaclass(type):
117
"Common behavior for the UDP and TCP server classes"
118
def __new__(cls, name, bases, attrs):
119
attrs["address_family"] = socket.AF_INET6
120
attrs["allow_reuse_address"] = True
121
def server_bind(self):
122
if self.options.interface:
123
if not hasattr(socket, "SO_BINDTODEVICE"):
124
# From /usr/include/asm-i486/socket.h
125
socket.SO_BINDTODEVICE = 25
127
self.socket.setsockopt(socket.SOL_SOCKET,
128
socket.SO_BINDTODEVICE,
129
self.options.interface)
130
except socket.error, error:
131
if error[0] == errno.EPERM:
132
print "Warning: No permission to bind to interface", \
133
self.options.interface
136
return super(type(self), self).server_bind()
137
attrs["server_bind"] = server_bind
138
def init(self, *args, **kwargs):
139
if "options" in kwargs:
140
self.options = kwargs["options"]
141
del kwargs["options"]
142
if "clients" in kwargs:
143
self.clients = kwargs["clients"]
144
del kwargs["clients"]
145
if "credentials" in kwargs:
146
self.credentials = kwargs["credentials"]
147
del kwargs["credentials"]
148
return super(type(self), self).__init__(*args, **kwargs)
149
attrs["__init__"] = init
150
return type.__new__(cls, name, bases, attrs)
153
class udp_handler(SocketServer.DatagramRequestHandler, object):
155
self.wfile.write("Polo")
156
print "UDP request answered"
159
class IPv6_UDPServer(SocketServer.UDPServer, object):
160
__metaclass__ = server_metaclass
161
def verify_request(self, request, client_address):
162
print "UDP request came"
163
return request[0] == "Marco"
258
def peer_certificate(session):
259
# If not an OpenPGP certificate...
260
if gnutls.library.functions.gnutls_certificate_type_get\
261
(session._c_object) \
262
!= gnutls.library.constants.GNUTLS_CRT_OPENPGP:
263
# ...do the normal thing
264
return session.peer_certificate
265
list_size = ctypes.c_uint()
266
cert_list = gnutls.library.functions.gnutls_certificate_get_peers\
267
(session._c_object, ctypes.byref(list_size))
268
if list_size.value == 0:
271
return ctypes.string_at(cert.data, cert.size)
274
def fingerprint(openpgp):
275
# New empty GnuTLS certificate
276
crt = gnutls.library.types.gnutls_openpgp_crt_t()
277
gnutls.library.functions.gnutls_openpgp_crt_init\
279
# New GnuTLS "datum" with the OpenPGP public key
280
datum = gnutls.library.types.gnutls_datum_t\
281
(ctypes.cast(ctypes.c_char_p(openpgp),
282
ctypes.POINTER(ctypes.c_ubyte)),
283
ctypes.c_uint(len(openpgp)))
284
# Import the OpenPGP public key into the certificate
285
ret = gnutls.library.functions.gnutls_openpgp_crt_import\
288
gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
289
# New buffer for the fingerprint
290
buffer = ctypes.create_string_buffer(20)
291
buffer_length = ctypes.c_size_t()
292
# Get the fingerprint from the certificate into the buffer
293
gnutls.library.functions.gnutls_openpgp_crt_get_fingerprint\
294
(crt, ctypes.byref(buffer), ctypes.byref(buffer_length))
295
# Deinit the certificate
296
gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
297
# Convert the buffer to a Python bytestring
298
fpr = ctypes.string_at(buffer, buffer_length.value)
299
# Convert the bytestring to hexadecimal notation
300
hex_fpr = u''.join(u"%02X" % ord(char) for char in fpr)
166
304
class tcp_handler(SocketServer.BaseRequestHandler, object):
305
"""A TCP request handler class.
306
Instantiated by IPv6_TCPServer for each request to handle it.
307
Note: This will run in its own forked process."""
167
309
def handle(self):
168
print "TCP request came"
169
print "Request:", self.request
170
print "Client Address:", self.client_address
171
print "Server:", self.server
172
session = gnutls.connection.ServerSession(self.request,
173
self.server.credentials)
175
if session.peer_certificate:
176
print "DN:", session.peer_certificate.subject
178
session.verify_peer()
179
except gnutls.errors.CertificateError, error:
180
print "Verify failed", error
184
session.send([client.password
185
for client in self.server.clients
187
session.peer_certificate.subject)][0])
189
session.send("gazonk")
310
logger.debug(u"TCP connection from: %s",
311
unicode(self.client_address))
312
session = gnutls.connection.ClientSession(self.request,
316
#priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
317
# "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
319
priority = "SECURE256"
321
gnutls.library.functions.gnutls_priority_set_direct\
322
(session._c_object, priority, None);
326
except gnutls.errors.GNUTLSError, error:
327
logger.debug(u"Handshake failed: %s", error)
328
# Do not run session.bye() here: the session is not
329
# established. Just abandon the request.
332
fpr = fingerprint(peer_certificate(session))
333
except (TypeError, gnutls.errors.GNUTLSError), error:
334
logger.debug(u"Bad certificate: %s", error)
337
logger.debug(u"Fingerprint: %s", fpr)
340
if c.fingerprint == fpr:
343
# Have to check if client.still_valid(), since it is possible
344
# that the client timed out while establishing the GnuTLS
346
if (not client) or (not client.still_valid()):
348
logger.debug(u"Client %(name)s is invalid",
351
logger.debug(u"Client not found for fingerprint: %s",
356
while sent_size < len(client.secret):
357
sent = session.send(client.secret[sent_size:])
358
logger.debug(u"Sent: %d, remaining: %d",
359
sent, len(client.secret)
360
- (sent_size + sent))
194
365
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
195
__metaclass__ = server_metaclass
366
"""IPv6 TCP server. Accepts 'None' as address and/or port.
368
options: Command line options
369
clients: Set() of Client objects
371
address_family = socket.AF_INET6
372
def __init__(self, *args, **kwargs):
373
if "options" in kwargs:
374
self.options = kwargs["options"]
375
del kwargs["options"]
376
if "clients" in kwargs:
377
self.clients = kwargs["clients"]
378
del kwargs["clients"]
379
return super(type(self), self).__init__(*args, **kwargs)
380
def server_bind(self):
381
"""This overrides the normal server_bind() function
382
to bind to an interface if one was specified, and also NOT to
383
bind to an address or port if they were not specified."""
384
if self.options.interface:
385
if not hasattr(socket, "SO_BINDTODEVICE"):
386
# From /usr/include/asm-i486/socket.h
387
socket.SO_BINDTODEVICE = 25
389
self.socket.setsockopt(socket.SOL_SOCKET,
390
socket.SO_BINDTODEVICE,
391
self.options.interface)
392
except socket.error, error:
393
if error[0] == errno.EPERM:
394
logger.warning(u"No permission to"
395
u" bind to interface %s",
396
self.options.interface)
399
# Only bind(2) the socket if we really need to.
400
if self.server_address[0] or self.server_address[1]:
401
if not self.server_address[0]:
403
self.server_address = (in6addr_any,
404
self.server_address[1])
405
elif self.server_address[1] is None:
406
self.server_address = (self.server_address[0],
408
return super(type(self), self).server_bind()
198
411
def string_to_delta(interval):
446
"""From the Avahi server example code"""
447
global group, serviceName, serviceType, servicePort, serviceTXT, \
450
group = dbus.Interface(
451
bus.get_object( avahi.DBUS_NAME,
452
server.EntryGroupNew()),
453
avahi.DBUS_INTERFACE_ENTRY_GROUP)
454
group.connect_to_signal('StateChanged',
455
entry_group_state_changed)
456
logger.debug(u"Adding service '%s' of type '%s' ...",
457
serviceName, serviceType)
460
serviceInterface, # interface
461
avahi.PROTO_INET6, # protocol
462
dbus.UInt32(0), # flags
463
serviceName, serviceType,
465
dbus.UInt16(servicePort),
466
avahi.string_array_to_txt_array(serviceTXT))
470
def remove_service():
471
"""From the Avahi server example code"""
474
if not group is None:
478
def server_state_changed(state):
479
"""From the Avahi server example code"""
480
if state == avahi.SERVER_COLLISION:
481
logger.warning(u"Server name collision")
483
elif state == avahi.SERVER_RUNNING:
487
def entry_group_state_changed(state, error):
488
"""From the Avahi server example code"""
489
global serviceName, server, rename_count
491
logger.debug(u"state change: %i", state)
493
if state == avahi.ENTRY_GROUP_ESTABLISHED:
494
logger.debug(u"Service established.")
495
elif state == avahi.ENTRY_GROUP_COLLISION:
497
rename_count = rename_count - 1
499
name = server.GetAlternativeServiceName(name)
500
logger.warning(u"Service name collision, "
501
u"changing name to '%s' ...", name)
506
logger.error(u"No suitable service name found "
507
u"after %i retries, exiting.",
510
elif state == avahi.ENTRY_GROUP_FAILURE:
511
logger.error(u"Error in group state changed %s",
517
def if_nametoindex(interface):
518
"""Call the C function if_nametoindex()"""
520
libc = ctypes.cdll.LoadLibrary("libc.so.6")
521
return libc.if_nametoindex(interface)
522
except (OSError, AttributeError):
523
if "struct" not in sys.modules:
525
if "fcntl" not in sys.modules:
527
SIOCGIFINDEX = 0x8933 # From /usr/include/linux/sockios.h
529
ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
530
struct.pack("16s16x", interface))
532
interface_index = struct.unpack("I", ifreq[16:20])[0]
533
return interface_index
536
if __name__ == '__main__':
233
537
parser = OptionParser()
234
538
parser.add_option("-i", "--interface", type="string",
235
default="eth0", metavar="IF",
236
help="Interface to bind to")
539
default=None, metavar="IF",
540
help="Bind to interface IF")
237
541
parser.add_option("--cert", type="string", default="cert.pem",
239
help="Public key certificate to use")
543
help="Public key certificate PEM file to use")
240
544
parser.add_option("--key", type="string", default="key.pem",
242
help="Private key to use")
546
help="Private key PEM file to use")
243
547
parser.add_option("--ca", type="string", default="ca.pem",
245
help="Certificate Authority certificate to use")
549
help="Certificate Authority certificate PEM file to use")
246
550
parser.add_option("--crl", type="string", default="crl.pem",
248
help="Certificate Revokation List to use")
249
parser.add_option("-p", "--port", type="int", default=49001,
552
help="Certificate Revokation List PEM file to use")
553
parser.add_option("-p", "--port", type="int", default=None,
250
554
help="Port number to receive requests on")
251
parser.add_option("--dh", type="int", metavar="BITS",
252
help="DH group to use")
253
parser.add_option("-t", "--timeout", type="string", # Parsed later
555
parser.add_option("--timeout", type="string", # Parsed later
255
557
help="Amount of downtime allowed for clients")
256
558
parser.add_option("--interval", type="string", # Parsed later
258
560
help="How often to check that a client is up")
259
561
parser.add_option("--check", action="store_true", default=False,
260
562
help="Run self-test")
563
parser.add_option("--debug", action="store_true", default=False,
261
565
(options, args) = parser.parse_args()
263
567
if options.check:
265
569
doctest.testmod()
270
574
options.timeout = string_to_delta(options.timeout)
271
575
except ValueError:
272
576
parser.error("option --timeout: Unparseable time")
275
578
options.interval = string_to_delta(options.interval)
276
579
except ValueError:
277
580
parser.error("option --interval: Unparseable time")
279
cert = gnutls.crypto.X509Certificate(open(options.cert).read())
280
key = gnutls.crypto.X509PrivateKey(open(options.key).read())
281
ca = gnutls.crypto.X509Certificate(open(options.ca).read())
282
crl = gnutls.crypto.X509CRL(open(options.crl).read())
283
cred = gnutls.connection.X509Credentials(cert, key, [ca], [crl])
285
582
# Parse config file
287
client_config_object = ConfigParser.SafeConfigParser(defaults)
288
client_config_object.read("mandos-clients.conf")
289
clients = Set(Client(name=section, options=options,
290
**(dict(client_config_object\
292
for section in client_config_object.sections())
295
udp_server = IPv6_UDPServer((in6addr_any, options.port),
299
tcp_server = IPv6_TCPServer((in6addr_any, options.port),
583
defaults = { "checker": "sleep 1; fping -q -- %%(fqdn)s" }
584
client_config = ConfigParser.SafeConfigParser(defaults)
585
#client_config.readfp(open("secrets.conf"), "secrets.conf")
586
client_config.read("mandos-clients.conf")
588
# From the Avahi server example code
589
DBusGMainLoop(set_as_default=True )
590
main_loop = gobject.MainLoop()
591
bus = dbus.SystemBus()
592
server = dbus.Interface(
593
bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
594
avahi.DBUS_INTERFACE_SERVER )
595
# End of Avahi example code
597
debug = options.debug
600
def remove_from_clients(client):
601
clients.remove(client)
603
logger.debug(u"No clients left, exiting")
606
clients.update(Set(Client(name=section, options=options,
607
stop_hook = remove_from_clients,
608
**(dict(client_config\
610
for section in client_config.sections()))
611
for client in clients:
614
tcp_server = IPv6_TCPServer((None, options.port),
309
next_stop = min(client.next_stop() for client in clients)
310
now = datetime.datetime.now()
312
delay = next_stop - now
313
delay_seconds = (delay.days * 24 * 60 * 60
315
+ delay.microseconds / 1000000)
316
clients_with_checkers = tuple(client for client in
320
input_checks = (udp_server, tcp_server) \
321
+ clients_with_checkers
322
print "Waiting for network",
323
if clients_with_checkers:
324
print "and checkers for:",
325
for client in clients_with_checkers:
328
input, out, err = select.select(input_checks, (), (),
333
for client in clients:
334
if client.it_is_time_to_check(now=now) and \
335
client.checker is None:
336
print "Starting checker for client %(name)s" \
338
client.start_checker()
339
# delete timed-out clients
340
for client in clients.copy():
341
if not client.still_valid(now=now):
343
print "Removing client %(name)s" % vars(client)
344
clients.remove(client)
345
except KeyboardInterrupt:
618
# Find out what random port we got
619
servicePort = tcp_server.socket.getsockname()[1]
620
logger.debug(u"Now listening on port %d", servicePort)
622
if options.interface is not None:
623
serviceInterface = if_nametoindex(options.interface)
625
# From the Avahi server example code
626
server.connect_to_signal("StateChanged", server_state_changed)
627
server_state_changed(server.GetState())
628
# End of Avahi example code
630
gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
631
lambda *args, **kwargs:
632
tcp_server.handle_request(*args[2:],
636
except KeyboardInterrupt:
641
# From the Avahi server example code
642
if not group is None:
644
# End of Avahi example code
349
646
for client in clients:
350
client.stop_checker()
353
if __name__ == "__main__":
647
client.stop_hook = None