9
11
import gnutls.crypto
10
12
import gnutls.connection
11
13
import gnutls.errors
14
import gnutls.library.functions
15
import gnutls.library.constants
16
import gnutls.library.types
12
17
import ConfigParser
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
14
56
class Client(object):
15
def __init__(self, name=None, dn=None, password=None,
16
passfile=None, fqdn=None, timeout=None,
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):
21
self.password = password
23
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()
25
print "No Password or Passfile in client config file"
26
# raise RuntimeError XXX
27
self.password = "gazonk"
124
raise RuntimeError(u"No secret or secfile for client %s"
126
self.fqdn = fqdn # string
127
self.created = datetime.datetime.now()
30
128
self.last_seen = None
31
129
if timeout is None:
32
timeout = self.server.options.timeout
130
timeout = options.timeout
33
131
self.timeout = timeout
34
132
if interval == -1:
35
interval = self.server.options.interval
133
interval = options.interval
135
interval = string_to_delta(interval)
36
136
self.interval = interval
38
def server_bind(self):
39
if self.options.interface:
40
if not hasattr(socket, "SO_BINDTODEVICE"):
41
# From /usr/include/asm-i486/socket.h
42
socket.SO_BINDTODEVICE = 25
44
self.socket.setsockopt(socket.SOL_SOCKET,
45
socket.SO_BINDTODEVICE,
46
self.options.interface)
47
except socket.error, error:
48
if error[0] == errno.EPERM:
49
print "Warning: Denied permission to bind to interface", \
50
self.options.interface
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."""
186
now = datetime.datetime.now()
187
if os.WIFEXITED(condition) \
188
and (os.WEXITSTATUS(condition) == 0):
189
logger.debug(u"Checker for %(name)s succeeded",
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?",
200
logger.debug(u"Checker for %(name)s failed",
203
self.checker_callback_tag = None
204
def start_checker(self):
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
238
def stop_checker(self):
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
244
os.kill(self.checker.pid, signal.SIGTERM)
245
if self.checker.poll() is None:
246
os.kill(self.checker.pid, signal.SIGKILL)
248
def still_valid(self, now=None):
249
"""Has the timeout not yet passed for this client?"""
251
now = datetime.datetime.now()
252
if self.last_seen is None:
253
return now < (self.created + self.timeout)
255
return now < (self.last_seen + self.timeout)
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)
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."""
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",
53
return super(type(self), self).server_bind()
56
def init_with_options(self, *args, **kwargs):
57
if "options" in kwargs:
58
self.options = kwargs["options"]
60
if "clients" in kwargs:
61
self.clients = kwargs["clients"]
63
if "credentials" in kwargs:
64
self.credentials = kwargs["credentials"]
65
del kwargs["credentials"]
66
return super(type(self), self).__init__(*args, **kwargs)
69
class udp_handler(SocketServer.DatagramRequestHandler, object):
71
self.wfile.write("Polo")
72
print "UDP request answered"
75
class IPv6_UDPServer(SocketServer.UDPServer, object):
76
__init__ = init_with_options
77
address_family = socket.AF_INET6
78
allow_reuse_address = True
79
server_bind = server_bind
80
def verify_request(self, request, client_address):
81
print "UDP request came"
82
return request[0] == "Marco"
85
class tcp_handler(SocketServer.BaseRequestHandler, object):
87
print "TCP request came"
88
print "Request:", self.request
89
print "Client Address:", self.client_address
90
print "Server:", self.server
91
session = gnutls.connection.ServerSession(self.request,
92
self.server.credentials)
94
if session.peer_certificate:
95
print "DN:", session.peer_certificate.subject
98
except gnutls.errors.CertificateError, error:
99
print "Verify failed", error
351
logger.debug(u"Client not found for fingerprint: %s",
103
session.send(dict((client.dn, client.password)
104
for client in self.server.clients)
105
[session.peer_certificate.subject])
107
session.send("gazonk")
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))
111
365
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
112
__init__ = init_with_options
366
"""IPv6 TCP server. Accepts 'None' as address and/or port.
368
options: Command line options
369
clients: Set() of Client objects
113
371
address_family = socket.AF_INET6
114
allow_reuse_address = True
115
request_queue_size = 1024
116
server_bind = server_bind
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()
411
def string_to_delta(interval):
412
"""Parse a string and return a datetime.timedelta
414
>>> string_to_delta('7d')
415
datetime.timedelta(7)
416
>>> string_to_delta('60s')
417
datetime.timedelta(0, 60)
418
>>> string_to_delta('60m')
419
datetime.timedelta(0, 3600)
420
>>> string_to_delta('24h')
421
datetime.timedelta(1)
422
>>> string_to_delta(u'1w')
423
datetime.timedelta(7)
426
suffix=unicode(interval[-1])
427
value=int(interval[:-1])
429
delta = datetime.timedelta(value)
431
delta = datetime.timedelta(0, value)
433
delta = datetime.timedelta(0, 0, 0, 0, value)
435
delta = datetime.timedelta(0, 0, 0, 0, 0, value)
437
delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
440
except (ValueError, IndexError):
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__':
124
537
parser = OptionParser()
125
538
parser.add_option("-i", "--interface", type="string",
126
default="eth0", metavar="IF",
127
help="Interface to bind to")
539
default=None, metavar="IF",
540
help="Bind to interface IF")
128
541
parser.add_option("--cert", type="string", default="cert.pem",
130
help="Public key certificate to use")
543
help="Public key certificate PEM file to use")
131
544
parser.add_option("--key", type="string", default="key.pem",
133
help="Private key to use")
546
help="Private key PEM file to use")
134
547
parser.add_option("--ca", type="string", default="ca.pem",
136
help="Certificate Authority certificate to use")
549
help="Certificate Authority certificate PEM file to use")
137
550
parser.add_option("--crl", type="string", default="crl.pem",
139
help="Certificate Revokation List to use")
140
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,
141
554
help="Port number to receive requests on")
142
parser.add_option("--dh", type="int", metavar="BITS",
143
help="DH group to use")
144
parser.add_option("-t", "--timeout", type="string", # Parsed later
555
parser.add_option("--timeout", type="string", # Parsed later
146
557
help="Amount of downtime allowed for clients")
558
parser.add_option("--interval", type="string", # Parsed later
560
help="How often to check that a client is up")
561
parser.add_option("--check", action="store_true", default=False,
562
help="Run self-test")
563
parser.add_option("--debug", action="store_true", default=False,
147
565
(options, args) = parser.parse_args()
149
# Parse the time argument
572
# Parse the time arguments
151
suffix=options.timeout[-1]
152
value=int(options.timeout[:-1])
154
options.timeout = datetime.timedelta(value)
156
options.timeout = datetime.timedelta(0, value)
158
options.timeout = datetime.timedelta(0, 0, 0, 0, value)
160
options.timeout = datetime.timedelta(0, 0, 0, 0, 0, value)
162
options.timeout = datetime.timedelta(0, 0, 0, 0, 0, 0,
166
except (ValueError, IndexError):
574
options.timeout = string_to_delta(options.timeout)
167
576
parser.error("option --timeout: Unparseable time")
169
cert = gnutls.crypto.X509Certificate(open(options.cert).read())
170
key = gnutls.crypto.X509PrivateKey(open(options.key).read())
171
ca = gnutls.crypto.X509Certificate(open(options.ca).read())
172
crl = gnutls.crypto.X509CRL(open(options.crl).read())
173
cred = gnutls.connection.X509Credentials(cert, key, [ca], [crl])
578
options.interval = string_to_delta(options.interval)
580
parser.error("option --interval: Unparseable time")
175
582
# Parse config file
177
client_config_object = ConfigParser.SafeConfigParser(defaults)
178
client_config_object.read("mandos-clients.conf")
179
clients = [Client(name=section,
180
**(dict(client_config_object.items(section))))
181
for section in client_config_object.sections()]
183
udp_server = IPv6_UDPServer((in6addr_any, options.port),
187
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),
194
in_, out, err = select.select((udp_server,
197
server.handle_request()
200
if __name__ == "__main__":
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
646
for client in clients:
647
client.stop_hook = None