12
9
import gnutls.crypto
13
10
import gnutls.connection
14
11
import gnutls.errors
15
import gnutls.library.functions
16
import gnutls.library.constants
17
import gnutls.library.types
18
12
import ConfigParser
31
from dbus.mainloop.glib import DBusGMainLoop
35
import logging.handlers
37
logger = logging.Logger('mandos')
38
syslogger = logging.handlers.SysLogHandler\
39
(facility = logging.handlers.SysLogHandler.LOG_DAEMON)
40
syslogger.setFormatter(logging.Formatter\
41
('%(levelname)s: %(message)s'))
42
logger.addHandler(syslogger)
45
# This variable is used to optionally bind to a specified interface.
46
# It is a global variable to fit in with the other variables from the
47
# Avahi server example code.
48
serviceInterface = avahi.IF_UNSPEC
49
# From the Avahi server example code:
50
serviceName = "Mandos"
51
serviceType = "_mandos._tcp" # http://www.dns-sd.org/ServiceTypes.html
52
servicePort = None # Not known at startup
53
serviceTXT = [] # TXT record for the service
54
domain = "" # Domain to publish on, default to .local
55
host = "" # Host to publish records for, default to localhost
56
group = None #our entry group
57
rename_count = 12 # Counter so we only rename after collisions a
58
# sensible number of times
59
# End of Avahi example code
62
16
class Client(object):
63
"""A representation of a client host served by this server.
65
name: string; from the config file, used in log messages
66
fingerprint: string (40 or 32 hexadecimal digits); used to
67
uniquely identify the client
68
secret: bytestring; sent verbatim (over TLS) to client
69
fqdn: string (FQDN); available for use by the checker command
70
created: datetime.datetime()
71
last_seen: datetime.datetime() or None if not yet seen
72
timeout: datetime.timedelta(); How long from last_seen until
73
this client is invalid
74
interval: datetime.timedelta(); How often to start a new checker
75
stop_hook: If set, called by stop() as stop_hook(self)
76
checker: subprocess.Popen(); a running checker process used
77
to see if the client lives.
78
Is None if no process is running.
79
checker_initiator_tag: a gobject event source tag, or None
80
stop_initiator_tag: - '' -
81
checker_callback_tag: - '' -
82
checker_command: string; External command which is run to check if
83
client lives. %()s expansions are done at
84
runtime with vars(self) as dict, so that for
85
instance %(name)s can be used in the command.
87
_timeout: Real variable for 'timeout'
88
_interval: Real variable for 'interval'
89
_timeout_milliseconds: Used by gobject.timeout_add()
90
_interval_milliseconds: - '' -
92
def _set_timeout(self, timeout):
93
"Setter function for 'timeout' attribute"
94
self._timeout = timeout
95
self._timeout_milliseconds = ((self.timeout.days
96
* 24 * 60 * 60 * 1000)
97
+ (self.timeout.seconds * 1000)
98
+ (self.timeout.microseconds
100
timeout = property(lambda self: self._timeout,
103
def _set_interval(self, interval):
104
"Setter function for 'interval' attribute"
105
self._interval = interval
106
self._interval_milliseconds = ((self.interval.days
107
* 24 * 60 * 60 * 1000)
108
+ (self.interval.seconds
110
+ (self.interval.microseconds
112
interval = property(lambda self: self._interval,
115
def __init__(self, name=None, options=None, stop_hook=None,
116
fingerprint=None, secret=None, secfile=None,
117
fqdn=None, timeout=None, interval=-1, checker=None):
17
def __init__(self, name=None, options=None, dn=None,
18
password=None, passfile=None, fqdn=None,
19
timeout=None, interval=-1):
119
# Uppercase and remove spaces from fingerprint
120
# for later comparison purposes with return value of
121
# the fingerprint() function
122
self.fingerprint = fingerprint.upper().replace(u" ", u"")
124
self.secret = secret.decode(u"base64")
127
self.secret = sf.read()
23
self.password = password
25
self.password = open(passfile).readall()
130
raise RuntimeError(u"No secret or secfile for client %s"
132
self.fqdn = fqdn # string
27
print "No Password or Passfile in client config file"
28
# raise RuntimeError XXX
29
self.password = "gazonk"
133
31
self.created = datetime.datetime.now()
134
32
self.last_seen = None
135
33
if timeout is None:
136
self.timeout = options.timeout
138
self.timeout = string_to_delta(timeout)
34
timeout = options.timeout
35
self.timeout = timeout
139
36
if interval == -1:
140
self.interval = options.interval
142
self.interval = string_to_delta(interval)
143
self.stop_hook = stop_hook
145
self.checker_initiator_tag = None
146
self.stop_initiator_tag = None
147
self.checker_callback_tag = None
148
self.check_command = checker
150
"""Start this clients checker and timeout hooks"""
151
# Schedule a new checker to be started an 'interval' from now,
152
# and every interval from then on.
153
self.checker_initiator_tag = gobject.timeout_add\
154
(self._interval_milliseconds,
156
# Also start a new checker *right now*.
158
# Schedule a stop() when 'timeout' has passed
159
self.stop_initiator_tag = gobject.timeout_add\
160
(self._timeout_milliseconds,
164
The possibility that this client might be restarted is left
165
open, but not currently used."""
166
logger.debug(u"Stopping client %s", self.name)
168
if self.stop_initiator_tag:
169
gobject.source_remove(self.stop_initiator_tag)
170
self.stop_initiator_tag = None
171
if self.checker_initiator_tag:
172
gobject.source_remove(self.checker_initiator_tag)
173
self.checker_initiator_tag = None
177
# Do not run this again if called by a gobject.timeout_add
180
# Some code duplication here and in stop()
181
if hasattr(self, "stop_initiator_tag") \
182
and self.stop_initiator_tag:
183
gobject.source_remove(self.stop_initiator_tag)
184
self.stop_initiator_tag = None
185
if hasattr(self, "checker_initiator_tag") \
186
and self.checker_initiator_tag:
187
gobject.source_remove(self.checker_initiator_tag)
188
self.checker_initiator_tag = None
190
def checker_callback(self, pid, condition):
191
"""The checker has completed, so take appropriate actions."""
192
now = datetime.datetime.now()
193
if os.WIFEXITED(condition) \
194
and (os.WEXITSTATUS(condition) == 0):
195
logger.debug(u"Checker for %(name)s succeeded",
198
gobject.source_remove(self.stop_initiator_tag)
199
self.stop_initiator_tag = gobject.timeout_add\
200
(self._timeout_milliseconds,
202
elif not os.WIFEXITED(condition):
203
logger.warning(u"Checker for %(name)s crashed?",
206
logger.debug(u"Checker for %(name)s failed",
209
self.checker_callback_tag = None
210
def start_checker(self):
211
"""Start a new checker subprocess if one is not running.
212
If a checker already exists, leave it running and do
214
if self.checker is None:
216
command = self.check_command % self.fqdn
218
escaped_attrs = dict((key, re.escape(str(val)))
220
vars(self).iteritems())
37
interval = options.interval
38
self.interval = interval
39
self.next_check = datetime.datetime.now()
42
class server_metaclass(type):
43
"Common behavior for the UDP and TCP server classes"
44
def __new__(cls, name, bases, attrs):
45
attrs["address_family"] = socket.AF_INET6
46
attrs["allow_reuse_address"] = True
47
def server_bind(self):
48
if self.options.interface:
49
if not hasattr(socket, "SO_BINDTODEVICE"):
50
# From /usr/include/asm-i486/socket.h
51
socket.SO_BINDTODEVICE = 25
222
command = self.check_command % escaped_attrs
223
except TypeError, error:
224
logger.critical(u'Could not format string "%s":'
225
u' %s', self.check_command, error)
226
return True # Try again later
228
logger.debug(u"Starting checker %r for %s",
230
self.checker = subprocess.\
232
close_fds=True, shell=True,
234
self.checker_callback_tag = gobject.child_watch_add\
236
self.checker_callback)
237
except subprocess.OSError, error:
238
logger.error(u"Failed to start subprocess: %s",
240
# Re-run this periodically if run by gobject.timeout_add
242
def stop_checker(self):
243
"""Force the checker process, if any, to stop."""
244
if not hasattr(self, "checker") or self.checker is None:
246
gobject.source_remove(self.checker_callback_tag)
247
self.checker_callback_tag = None
248
os.kill(self.checker.pid, signal.SIGTERM)
249
if self.checker.poll() is None:
250
os.kill(self.checker.pid, signal.SIGKILL)
252
def still_valid(self, now=None):
253
"""Has the timeout not yet passed for this client?"""
255
now = datetime.datetime.now()
256
if self.last_seen is None:
257
return now < (self.created + self.timeout)
259
return now < (self.last_seen + self.timeout)
262
def peer_certificate(session):
263
"Return an OpenPGP data packet string for the peer's certificate"
264
# If not an OpenPGP certificate...
265
if gnutls.library.functions.gnutls_certificate_type_get\
266
(session._c_object) \
267
!= gnutls.library.constants.GNUTLS_CRT_OPENPGP:
268
# ...do the normal thing
269
return session.peer_certificate
270
list_size = ctypes.c_uint()
271
cert_list = gnutls.library.functions.gnutls_certificate_get_peers\
272
(session._c_object, ctypes.byref(list_size))
273
if list_size.value == 0:
276
return ctypes.string_at(cert.data, cert.size)
279
def fingerprint(openpgp):
280
"Convert an OpenPGP data string to a hexdigit fingerprint string"
281
# New empty GnuTLS certificate
282
crt = gnutls.library.types.gnutls_openpgp_crt_t()
283
gnutls.library.functions.gnutls_openpgp_crt_init\
285
# New GnuTLS "datum" with the OpenPGP public key
286
datum = gnutls.library.types.gnutls_datum_t\
287
(ctypes.cast(ctypes.c_char_p(openpgp),
288
ctypes.POINTER(ctypes.c_ubyte)),
289
ctypes.c_uint(len(openpgp)))
290
# Import the OpenPGP public key into the certificate
291
ret = gnutls.library.functions.gnutls_openpgp_crt_import\
294
gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
295
# New buffer for the fingerprint
296
buffer = ctypes.create_string_buffer(20)
297
buffer_length = ctypes.c_size_t()
298
# Get the fingerprint from the certificate into the buffer
299
gnutls.library.functions.gnutls_openpgp_crt_get_fingerprint\
300
(crt, ctypes.byref(buffer), ctypes.byref(buffer_length))
301
# Deinit the certificate
302
gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
303
# Convert the buffer to a Python bytestring
304
fpr = ctypes.string_at(buffer, buffer_length.value)
305
# Convert the bytestring to hexadecimal notation
306
hex_fpr = u''.join(u"%02X" % ord(char) for char in fpr)
53
self.socket.setsockopt(socket.SOL_SOCKET,
54
socket.SO_BINDTODEVICE,
55
self.options.interface)
56
except socket.error, error:
57
if error[0] == errno.EPERM:
58
print "Warning: No permission to bind to interface", \
59
self.options.interface
62
return super(type(self), self).server_bind()
63
attrs["server_bind"] = server_bind
64
def init(self, *args, **kwargs):
65
if "options" in kwargs:
66
self.options = kwargs["options"]
68
if "clients" in kwargs:
69
self.clients = kwargs["clients"]
71
if "credentials" in kwargs:
72
self.credentials = kwargs["credentials"]
73
del kwargs["credentials"]
74
return super(type(self), self).__init__(*args, **kwargs)
75
attrs["__init__"] = init
76
return type.__new__(cls, name, bases, attrs)
79
class udp_handler(SocketServer.DatagramRequestHandler, object):
81
self.wfile.write("Polo")
82
print "UDP request answered"
85
class IPv6_UDPServer(SocketServer.UDPServer, object):
86
__metaclass__ = server_metaclass
87
def verify_request(self, request, client_address):
88
print "UDP request came"
89
return request[0] == "Marco"
310
92
class tcp_handler(SocketServer.BaseRequestHandler, object):
311
"""A TCP request handler class.
312
Instantiated by IPv6_TCPServer for each request to handle it.
313
Note: This will run in its own forked process."""
316
logger.debug(u"TCP connection from: %s",
317
unicode(self.client_address))
318
session = gnutls.connection.ClientSession(self.request,
322
#priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
323
# "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
325
priority = "SECURE256"
327
gnutls.library.functions.gnutls_priority_set_direct\
328
(session._c_object, priority, None);
332
except gnutls.errors.GNUTLSError, error:
333
logger.debug(u"Handshake failed: %s", error)
334
# Do not run session.bye() here: the session is not
335
# established. Just abandon the request.
338
fpr = fingerprint(peer_certificate(session))
339
except (TypeError, gnutls.errors.GNUTLSError), error:
340
logger.debug(u"Bad certificate: %s", error)
343
logger.debug(u"Fingerprint: %s", fpr)
346
if c.fingerprint == fpr:
349
# Have to check if client.still_valid(), since it is possible
350
# that the client timed out while establishing the GnuTLS
352
if (not client) or (not client.still_valid()):
354
logger.debug(u"Client %(name)s is invalid",
357
logger.debug(u"Client not found for fingerprint: %s",
362
while sent_size < len(client.secret):
363
sent = session.send(client.secret[sent_size:])
364
logger.debug(u"Sent: %d, remaining: %d",
365
sent, len(client.secret)
366
- (sent_size + sent))
94
print "TCP request came"
95
print "Request:", self.request
96
print "Client Address:", self.client_address
97
print "Server:", self.server
98
session = gnutls.connection.ServerSession(self.request,
99
self.server.credentials)
101
if session.peer_certificate:
102
print "DN:", session.peer_certificate.subject
104
session.verify_peer()
105
except gnutls.errors.CertificateError, error:
106
print "Verify failed", error
110
session.send(dict((client.dn, client.password)
111
for client in self.server.clients)
112
[session.peer_certificate.subject])
114
session.send("gazonk")
371
119
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
372
"""IPv6 TCP server. Accepts 'None' as address and/or port.
374
options: Command line options
375
clients: Set() of Client objects
377
address_family = socket.AF_INET6
378
def __init__(self, *args, **kwargs):
379
if "options" in kwargs:
380
self.options = kwargs["options"]
381
del kwargs["options"]
382
if "clients" in kwargs:
383
self.clients = kwargs["clients"]
384
del kwargs["clients"]
385
return super(type(self), self).__init__(*args, **kwargs)
386
def server_bind(self):
387
"""This overrides the normal server_bind() function
388
to bind to an interface if one was specified, and also NOT to
389
bind to an address or port if they were not specified."""
390
if self.options.interface:
391
if not hasattr(socket, "SO_BINDTODEVICE"):
392
# From /usr/include/asm-i486/socket.h
393
socket.SO_BINDTODEVICE = 25
395
self.socket.setsockopt(socket.SOL_SOCKET,
396
socket.SO_BINDTODEVICE,
397
self.options.interface)
398
except socket.error, error:
399
if error[0] == errno.EPERM:
400
logger.warning(u"No permission to"
401
u" bind to interface %s",
402
self.options.interface)
405
# Only bind(2) the socket if we really need to.
406
if self.server_address[0] or self.server_address[1]:
407
if not self.server_address[0]:
409
self.server_address = (in6addr_any,
410
self.server_address[1])
411
elif self.server_address[1] is None:
412
self.server_address = (self.server_address[0],
414
return super(type(self), self).server_bind()
120
__metaclass__ = server_metaclass
121
request_queue_size = 1024
417
126
def string_to_delta(interval):
418
127
"""Parse a string and return a datetime.timedelta
452
"""From the Avahi server example code"""
453
global group, serviceName, serviceType, servicePort, serviceTXT, \
456
group = dbus.Interface(
457
bus.get_object( avahi.DBUS_NAME,
458
server.EntryGroupNew()),
459
avahi.DBUS_INTERFACE_ENTRY_GROUP)
460
group.connect_to_signal('StateChanged',
461
entry_group_state_changed)
462
logger.debug(u"Adding service '%s' of type '%s' ...",
463
serviceName, serviceType)
466
serviceInterface, # interface
467
avahi.PROTO_INET6, # protocol
468
dbus.UInt32(0), # flags
469
serviceName, serviceType,
471
dbus.UInt16(servicePort),
472
avahi.string_array_to_txt_array(serviceTXT))
476
def remove_service():
477
"""From the Avahi server example code"""
480
if not group is None:
484
def server_state_changed(state):
485
"""From the Avahi server example code"""
486
if state == avahi.SERVER_COLLISION:
487
logger.warning(u"Server name collision")
489
elif state == avahi.SERVER_RUNNING:
493
def entry_group_state_changed(state, error):
494
"""From the Avahi server example code"""
495
global serviceName, server, rename_count
497
logger.debug(u"state change: %i", state)
499
if state == avahi.ENTRY_GROUP_ESTABLISHED:
500
logger.debug(u"Service established.")
501
elif state == avahi.ENTRY_GROUP_COLLISION:
503
rename_count = rename_count - 1
505
name = server.GetAlternativeServiceName(name)
506
logger.warning(u"Service name collision, "
507
u"changing name to '%s' ...", name)
512
logger.error(u"No suitable service name found after %i"
513
u" retries, exiting.", n_rename)
515
elif state == avahi.ENTRY_GROUP_FAILURE:
516
logger.error(u"Error in group state changed %s",
521
def if_nametoindex(interface):
522
"""Call the C function if_nametoindex()"""
524
libc = ctypes.cdll.LoadLibrary("libc.so.6")
525
return libc.if_nametoindex(interface)
526
except (OSError, AttributeError):
527
if "struct" not in sys.modules:
529
if "fcntl" not in sys.modules:
531
SIOCGIFINDEX = 0x8933 # From /usr/include/linux/sockios.h
533
ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
534
struct.pack("16s16x", interface))
536
interface_index = struct.unpack("I", ifreq[16:20])[0]
537
return interface_index
540
def daemon(nochdir, noclose):
541
"""See daemon(3). Standard BSD Unix function.
542
This should really exist as os.daemon, but it doesn't (yet)."""
549
# Close all standard open file descriptors
550
null = os.open("/dev/null", os.O_NOCTTY | os.O_RDWR)
551
if not stat.S_ISCHR(os.fstat(null).st_mode):
552
raise OSError(errno.ENODEV,
553
"/dev/null not a character device")
554
os.dup2(null, sys.stdin.fileno())
555
os.dup2(null, sys.stdout.fileno())
556
os.dup2(null, sys.stderr.fileno())
561
def killme(status = 0):
562
logger.debug("Stopping server with exit status %d", status)
564
if main_loop_started:
570
if __name__ == '__main__':
572
main_loop_started = False
573
161
parser = OptionParser()
574
162
parser.add_option("-i", "--interface", type="string",
575
default=None, metavar="IF",
576
help="Bind to interface IF")
577
parser.add_option("-p", "--port", type="int", default=None,
163
default="eth0", metavar="IF",
164
help="Interface to bind to")
165
parser.add_option("--cert", type="string", default="cert.pem",
167
help="Public key certificate to use")
168
parser.add_option("--key", type="string", default="key.pem",
170
help="Private key to use")
171
parser.add_option("--ca", type="string", default="ca.pem",
173
help="Certificate Authority certificate to use")
174
parser.add_option("--crl", type="string", default="crl.pem",
176
help="Certificate Revokation List to use")
177
parser.add_option("-p", "--port", type="int", default=49001,
578
178
help="Port number to receive requests on")
579
parser.add_option("--timeout", type="string", # Parsed later
179
parser.add_option("--dh", type="int", metavar="BITS",
180
help="DH group to use")
181
parser.add_option("-t", "--timeout", type="string", # Parsed later
581
183
help="Amount of downtime allowed for clients")
582
184
parser.add_option("--interval", type="string", # Parsed later
584
186
help="How often to check that a client is up")
585
187
parser.add_option("--check", action="store_true", default=False,
586
188
help="Run self-test")
587
parser.add_option("--debug", action="store_true", default=False,
589
189
(options, args) = parser.parse_args()
591
191
if options.check:
593
193
doctest.testmod()
598
198
options.timeout = string_to_delta(options.timeout)
599
199
except ValueError:
600
200
parser.error("option --timeout: Unparseable time")
602
203
options.interval = string_to_delta(options.interval)
603
204
except ValueError:
604
205
parser.error("option --interval: Unparseable time")
207
cert = gnutls.crypto.X509Certificate(open(options.cert).read())
208
key = gnutls.crypto.X509PrivateKey(open(options.key).read())
209
ca = gnutls.crypto.X509Certificate(open(options.ca).read())
210
crl = gnutls.crypto.X509CRL(open(options.crl).read())
211
cred = gnutls.connection.X509Credentials(cert, key, [ca], [crl])
606
213
# Parse config file
607
defaults = { "checker": "fping -q -- %%(fqdn)s" }
608
client_config = ConfigParser.SafeConfigParser(defaults)
609
#client_config.readfp(open("secrets.conf"), "secrets.conf")
610
client_config.read("mandos-clients.conf")
612
# From the Avahi server example code
613
DBusGMainLoop(set_as_default=True )
614
main_loop = gobject.MainLoop()
615
bus = dbus.SystemBus()
616
server = dbus.Interface(
617
bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
618
avahi.DBUS_INTERFACE_SERVER )
619
# End of Avahi example code
621
debug = options.debug
624
console = logging.StreamHandler()
625
# console.setLevel(logging.DEBUG)
626
console.setFormatter(logging.Formatter\
627
('%(levelname)s: %(message)s'))
628
logger.addHandler(console)
632
def remove_from_clients(client):
633
clients.remove(client)
635
logger.debug(u"No clients left, exiting")
638
clients.update(Set(Client(name=section, options=options,
639
stop_hook = remove_from_clients,
640
**(dict(client_config\
642
for section in client_config.sections()))
648
"Cleanup function; run on exit"
650
# From the Avahi server example code
651
if not group is None:
654
# End of Avahi example code
656
for client in clients:
657
client.stop_hook = None
660
atexit.register(cleanup)
663
signal.signal(signal.SIGINT, signal.SIG_IGN)
664
signal.signal(signal.SIGHUP, lambda signum, frame: killme())
665
signal.signal(signal.SIGTERM, lambda signum, frame: killme())
667
for client in clients:
670
tcp_server = IPv6_TCPServer((None, options.port),
215
client_config_object = ConfigParser.SafeConfigParser(defaults)
216
client_config_object.read("mandos-clients.conf")
217
clients = [Client(name=section, options=options,
218
**(dict(client_config_object.items(section))))
219
for section in client_config_object.sections()]
221
udp_server = IPv6_UDPServer((in6addr_any, options.port),
225
tcp_server = IPv6_TCPServer((in6addr_any, options.port),
674
# Find out what random port we got
675
servicePort = tcp_server.socket.getsockname()[1]
676
logger.debug(u"Now listening on port %d", servicePort)
678
if options.interface is not None:
679
serviceInterface = if_nametoindex(options.interface)
681
# From the Avahi server example code
682
server.connect_to_signal("StateChanged", server_state_changed)
684
server_state_changed(server.GetState())
685
except dbus.exceptions.DBusException, error:
686
logger.critical(u"DBusException: %s", error)
688
# End of Avahi example code
690
gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
691
lambda *args, **kwargs:
692
tcp_server.handle_request(*args[2:],
695
main_loop_started = True
697
except KeyboardInterrupt:
232
in_, out, err = select.select((udp_server,
235
server.handle_request()
238
if __name__ == "__main__":