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  • Committer: Björn Påhlsson
  • Date: 2008-07-20 02:52:20 UTC
  • Revision ID: belorn@braxen-20080720025220-r5u0388uy9iu23h6
Added following support:
Pluginbased client handler
rewritten Mandos client
       Avahi instead of udp server discovery
       openpgp encrypted key support
Passprompt stand alone application for direct console input
Added logging for Mandos server

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#!/usr/bin/python
2
 
# -*- mode: python; coding: utf-8 -*-
3
 
4
 
# Mandos server - give out binary blobs to connecting clients.
5
 
6
 
# This program is partly derived from an example program for an Avahi
7
 
# service publisher, downloaded from
8
 
# <http://avahi.org/wiki/PythonPublishExample>.  This includes the
9
 
# methods "add" and "remove" in the "AvahiService" class, the
10
 
# "server_state_changed" and "entry_group_state_changed" functions,
11
 
# and some lines in "main".
12
 
13
 
# Everything else is
14
 
# Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
15
 
16
 
# This program is free software: you can redistribute it and/or modify
17
 
# it under the terms of the GNU General Public License as published by
18
 
# the Free Software Foundation, either version 3 of the License, or
19
 
# (at your option) any later version.
20
 
#
21
 
#     This program is distributed in the hope that it will be useful,
22
 
#     but WITHOUT ANY WARRANTY; without even the implied warranty of
23
 
#     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24
 
#     GNU General Public License for more details.
25
 
26
 
# You should have received a copy of the GNU General Public License
27
 
# along with this program.  If not, see
28
 
# <http://www.gnu.org/licenses/>.
29
 
30
 
# Contact the authors at <mandos@fukt.bsnet.se>.
31
 
32
2
 
33
3
from __future__ import division
34
4
 
51
21
import signal
52
22
from sets import Set
53
23
import subprocess
54
 
import atexit
55
 
import stat
56
 
import logging
57
 
import logging.handlers
58
24
 
59
25
import dbus
60
26
import gobject
62
28
from dbus.mainloop.glib import DBusGMainLoop
63
29
import ctypes
64
30
 
65
 
version = "1.0"
 
31
import logging
 
32
import logging.handlers
 
33
 
 
34
# logghandler.setFormatter(logging.Formatter('%(levelname)s %(message)s')
66
35
 
67
36
logger = logging.Logger('mandos')
68
 
syslogger = logging.handlers.SysLogHandler\
69
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
70
 
             address = "/dev/log")
71
 
syslogger.setFormatter(logging.Formatter\
72
 
                        ('Mandos: %(levelname)s: %(message)s'))
73
 
logger.addHandler(syslogger)
74
 
 
75
 
console = logging.StreamHandler()
76
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
77
 
                                       ' %(message)s'))
78
 
logger.addHandler(console)
79
 
 
80
 
class AvahiError(Exception):
81
 
    def __init__(self, value):
82
 
        self.value = value
83
 
    def __str__(self):
84
 
        return repr(self.value)
85
 
 
86
 
class AvahiServiceError(AvahiError):
87
 
    pass
88
 
 
89
 
class AvahiGroupError(AvahiError):
90
 
    pass
91
 
 
92
 
 
93
 
class AvahiService(object):
94
 
    """An Avahi (Zeroconf) service.
95
 
    Attributes:
96
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
97
 
               Used to optionally bind to the specified interface.
98
 
    name: string; Example: 'Mandos'
99
 
    type: string; Example: '_mandos._tcp'.
100
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
101
 
    port: integer; what port to announce
102
 
    TXT: list of strings; TXT record for the service
103
 
    domain: string; Domain to publish on, default to .local if empty.
104
 
    host: string; Host to publish records for, default is localhost
105
 
    max_renames: integer; maximum number of renames
106
 
    rename_count: integer; counter so we only rename after collisions
107
 
                  a sensible number of times
108
 
    """
109
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
110
 
                 type = None, port = None, TXT = None, domain = "",
111
 
                 host = "", max_renames = 32768):
112
 
        self.interface = interface
113
 
        self.name = name
114
 
        self.type = type
115
 
        self.port = port
116
 
        if TXT is None:
117
 
            self.TXT = []
118
 
        else:
119
 
            self.TXT = TXT
120
 
        self.domain = domain
121
 
        self.host = host
122
 
        self.rename_count = 0
123
 
        self.max_renames = max_renames
124
 
    def rename(self):
125
 
        """Derived from the Avahi example code"""
126
 
        if self.rename_count >= self.max_renames:
127
 
            logger.critical(u"No suitable Zeroconf service name found"
128
 
                            u" after %i retries, exiting.",
129
 
                            rename_count)
130
 
            raise AvahiServiceError("Too many renames")
131
 
        self.name = server.GetAlternativeServiceName(self.name)
132
 
        logger.info(u"Changing Zeroconf service name to %r ...",
133
 
                    str(self.name))
134
 
        syslogger.setFormatter(logging.Formatter\
135
 
                               ('Mandos (%s): %%(levelname)s:'
136
 
                               ' %%(message)s' % self.name))
137
 
        self.remove()
138
 
        self.add()
139
 
        self.rename_count += 1
140
 
    def remove(self):
141
 
        """Derived from the Avahi example code"""
142
 
        if group is not None:
143
 
            group.Reset()
144
 
    def add(self):
145
 
        """Derived from the Avahi example code"""
146
 
        global group
147
 
        if group is None:
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 Zeroconf service '%s' of type '%s' ...",
155
 
                     service.name, service.type)
156
 
        group.AddService(
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))
164
 
        group.Commit()
165
 
 
166
 
# From the Avahi example code:
167
 
group = None                            # our entry group
 
37
logger.addHandler(logging.handlers.SysLogHandler(facility = logging.handlers.SysLogHandler.LOG_DAEMON))
 
38
 
 
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
168
53
# End of Avahi example code
169
54
 
170
55
 
175
60
    fingerprint: string (40 or 32 hexadecimal digits); used to
176
61
                 uniquely identify the client
177
62
    secret:    bytestring; sent verbatim (over TLS) to client
178
 
    host:      string; 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
 
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
183
68
    interval:  datetime.timedelta(); How often to start a new checker
184
69
    stop_hook: If set, called by stop() as stop_hook(self)
185
70
    checker:   subprocess.Popen(); a running checker process used
186
71
                                   to see if the client lives.
187
 
                                   'None' if no process is running.
 
72
                                   Is None if no process is running.
188
73
    checker_initiator_tag: a gobject event source tag, or None
189
74
    stop_initiator_tag:    - '' -
190
75
    checker_callback_tag:  - '' -
191
76
    checker_command: string; External command which is run to check if
192
 
                     client lives.  %() expansions are done at
 
77
                     client lives.  %()s expansions are done at
193
78
                     runtime with vars(self) as dict, so that for
194
79
                     instance %(name)s can be used in the command.
195
80
    Private attibutes:
196
81
    _timeout: Real variable for 'timeout'
197
82
    _interval: Real variable for 'interval'
198
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
 
83
    _timeout_milliseconds: Used by gobject.timeout_add()
199
84
    _interval_milliseconds: - '' -
200
85
    """
201
86
    def _set_timeout(self, timeout):
221
106
    interval = property(lambda self: self._interval,
222
107
                        _set_interval)
223
108
    del _set_interval
224
 
    def __init__(self, name = None, stop_hook=None, config={}):
225
 
        """Note: the 'checker' key in 'config' sets the
226
 
        'checker_command' attribute and *not* the 'checker'
227
 
        attribute."""
 
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):
228
112
        self.name = name
229
 
        logger.debug(u"Creating client %r", self.name)
230
 
        # Uppercase and remove spaces from fingerprint for later
231
 
        # comparison purposes with return value from the fingerprint()
232
 
        # function
233
 
        self.fingerprint = config["fingerprint"].upper()\
234
 
                           .replace(u" ", u"")
235
 
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
236
 
        if "secret" in config:
237
 
            self.secret = config["secret"].decode(u"base64")
238
 
        elif "secfile" in config:
239
 
            sf = open(config["secfile"])
 
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"")
 
117
        if secret:
 
118
            self.secret = secret.decode(u"base64")
 
119
        elif secfile:
 
120
            sf = open(secfile)
240
121
            self.secret = sf.read()
241
122
            sf.close()
242
123
        else:
243
 
            raise TypeError(u"No secret or secfile for client %s"
244
 
                            % self.name)
245
 
        self.host = config.get("host", "")
 
124
            raise RuntimeError(u"No secret or secfile for client %s"
 
125
                               % self.name)
 
126
        self.fqdn = fqdn                # string
246
127
        self.created = datetime.datetime.now()
247
 
        self.last_checked_ok = None
248
 
        self.timeout = string_to_delta(config["timeout"])
249
 
        self.interval = string_to_delta(config["interval"])
 
128
        self.last_seen = None
 
129
        if timeout is None:
 
130
            timeout = options.timeout
 
131
        self.timeout = timeout
 
132
        if interval == -1:
 
133
            interval = options.interval
 
134
        else:
 
135
            interval = string_to_delta(interval)
 
136
        self.interval = interval
250
137
        self.stop_hook = stop_hook
251
138
        self.checker = None
252
139
        self.checker_initiator_tag = None
253
140
        self.stop_initiator_tag = None
254
141
        self.checker_callback_tag = None
255
 
        self.check_command = config["checker"]
 
142
        self.check_command = checker
256
143
    def start(self):
257
 
        """Start this client's checker and timeout hooks"""
 
144
        """Start this clients checker and timeout hooks"""
258
145
        # Schedule a new checker to be started an 'interval' from now,
259
146
        # and every interval from then on.
260
147
        self.checker_initiator_tag = gobject.timeout_add\
268
155
                                   self.stop)
269
156
    def stop(self):
270
157
        """Stop this client.
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.
274
 
        if hasattr(self, "secret") and self.secret:
275
 
            logger.info(u"Stopping client %s", self.name)
276
 
            self.secret = None
277
 
        else:
278
 
            return False
279
 
        if getattr(self, "stop_initiator_tag", False):
 
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)
 
161
        self.secret = None
 
162
        if self.stop_initiator_tag:
280
163
            gobject.source_remove(self.stop_initiator_tag)
281
164
            self.stop_initiator_tag = None
282
 
        if getattr(self, "checker_initiator_tag", False):
 
165
        if self.checker_initiator_tag:
283
166
            gobject.source_remove(self.checker_initiator_tag)
284
167
            self.checker_initiator_tag = None
285
168
        self.stop_checker()
288
171
        # Do not run this again if called by a gobject.timeout_add
289
172
        return False
290
173
    def __del__(self):
291
 
        self.stop_hook = None
292
 
        self.stop()
 
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
 
183
        self.stop_checker()
293
184
    def checker_callback(self, pid, condition):
294
185
        """The checker has completed, so take appropriate actions."""
295
186
        now = datetime.datetime.now()
296
 
        self.checker_callback_tag = None
297
 
        self.checker = None
298
187
        if os.WIFEXITED(condition) \
299
188
               and (os.WEXITSTATUS(condition) == 0):
300
 
            logger.info(u"Checker for %(name)s succeeded",
301
 
                        vars(self))
302
 
            self.last_checked_ok = now
 
189
            logger.debug(u"Checker for %(name)s succeeded",
 
190
                         vars(self))
 
191
            self.last_seen = now
303
192
            gobject.source_remove(self.stop_initiator_tag)
304
193
            self.stop_initiator_tag = gobject.timeout_add\
305
194
                                      (self._timeout_milliseconds,
306
195
                                       self.stop)
307
 
        elif not os.WIFEXITED(condition):
 
196
        if not os.WIFEXITED(condition):
308
197
            logger.warning(u"Checker for %(name)s crashed?",
309
198
                           vars(self))
310
199
        else:
311
 
            logger.info(u"Checker for %(name)s failed",
312
 
                        vars(self))
 
200
            logger.debug(u"Checker for %(name)s failed",
 
201
                         vars(self))
 
202
            self.checker = None
 
203
        self.checker_callback_tag = None
313
204
    def start_checker(self):
314
205
        """Start a new checker subprocess if one is not running.
315
206
        If a checker already exists, leave it running and do
316
207
        nothing."""
317
 
        # The reason for not killing a running checker is that if we
318
 
        # did that, then if a checker (for some reason) started
319
 
        # running slowly and taking more than 'interval' time, the
320
 
        # client would inevitably timeout, since no checker would get
321
 
        # a chance to run to completion.  If we instead leave running
322
 
        # checkers alone, the checker would have to take more time
323
 
        # than 'timeout' for the client to be declared invalid, which
324
 
        # is as it should be.
325
208
        if self.checker is None:
 
209
            logger.debug(u"Starting checker for %s",
 
210
                         self.name)
326
211
            try:
327
 
                # In case check_command has exactly one % operator
328
 
                command = self.check_command % self.host
 
212
                command = self.check_command % self.fqdn
329
213
            except TypeError:
330
 
                # Escape attributes for the shell
331
214
                escaped_attrs = dict((key, re.escape(str(val)))
332
215
                                     for key, val in
333
216
                                     vars(self).iteritems())
334
217
                try:
335
218
                    command = self.check_command % escaped_attrs
336
219
                except TypeError, error:
337
 
                    logger.error(u'Could not format string "%s":'
338
 
                                 u' %s', self.check_command, error)
 
220
                    logger.critical(u'Could not format string "%s": %s',
 
221
                                    self.check_command, error)
339
222
                    return True # Try again later
340
223
            try:
341
 
                logger.info(u"Starting checker %r for %s",
342
 
                            command, self.name)
343
 
                # We don't need to redirect stdout and stderr, since
344
 
                # in normal mode, that is already done by daemon(),
345
 
                # and in debug mode we don't want to.  (Stdin is
346
 
                # always replaced by /dev/null.)
347
 
                self.checker = subprocess.Popen(command,
348
 
                                                close_fds=True,
349
 
                                                shell=True, cwd="/")
350
 
                self.checker_callback_tag = gobject.child_watch_add\
351
 
                                            (self.checker.pid,
352
 
                                             self.checker_callback)
353
 
            except OSError, error:
 
224
                self.checker = subprocess.\
 
225
                               Popen(command,
 
226
                                     stdout=subprocess.PIPE,
 
227
                                     close_fds=True, shell=True,
 
228
                                     cwd="/")
 
229
                self.checker_callback_tag = gobject.\
 
230
                                            child_watch_add(self.checker.pid,
 
231
                                                            self.\
 
232
                                                            checker_callback)
 
233
            except subprocess.OSError, error:
354
234
                logger.error(u"Failed to start subprocess: %s",
355
235
                             error)
356
236
        # Re-run this periodically if run by gobject.timeout_add
357
237
        return True
358
238
    def stop_checker(self):
359
239
        """Force the checker process, if any, to stop."""
360
 
        if self.checker_callback_tag:
361
 
            gobject.source_remove(self.checker_callback_tag)
362
 
            self.checker_callback_tag = None
363
 
        if getattr(self, "checker", None) is None:
 
240
        if not hasattr(self, "checker") or self.checker is None:
364
241
            return
365
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
366
 
        try:
367
 
            os.kill(self.checker.pid, signal.SIGTERM)
368
 
            #os.sleep(0.5)
369
 
            #if self.checker.poll() is None:
370
 
            #    os.kill(self.checker.pid, signal.SIGKILL)
371
 
        except OSError, error:
372
 
            if error.errno != errno.ESRCH: # No such process
373
 
                raise
 
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)
374
247
        self.checker = None
375
 
    def still_valid(self):
 
248
    def still_valid(self, now=None):
376
249
        """Has the timeout not yet passed for this client?"""
377
 
        now = datetime.datetime.now()
378
 
        if self.last_checked_ok is None:
 
250
        if now is None:
 
251
            now = datetime.datetime.now()
 
252
        if self.last_seen is None:
379
253
            return now < (self.created + self.timeout)
380
254
        else:
381
 
            return now < (self.last_checked_ok + self.timeout)
 
255
            return now < (self.last_seen + self.timeout)
382
256
 
383
257
 
384
258
def peer_certificate(session):
385
 
    "Return the peer's OpenPGP certificate as a bytestring"
386
259
    # If not an OpenPGP certificate...
387
260
    if gnutls.library.functions.gnutls_certificate_type_get\
388
261
            (session._c_object) \
399
272
 
400
273
 
401
274
def fingerprint(openpgp):
402
 
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
 
275
    # New empty GnuTLS certificate
 
276
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
277
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
278
        (ctypes.byref(crt))
403
279
    # New GnuTLS "datum" with the OpenPGP public key
404
280
    datum = gnutls.library.types.gnutls_datum_t\
405
281
        (ctypes.cast(ctypes.c_char_p(openpgp),
406
282
                     ctypes.POINTER(ctypes.c_ubyte)),
407
283
         ctypes.c_uint(len(openpgp)))
408
 
    # New empty GnuTLS certificate
409
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
410
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
411
 
        (ctypes.byref(crt))
412
284
    # Import the OpenPGP public key into the certificate
413
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
414
 
                    (crt, ctypes.byref(datum),
415
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
416
 
    # Verify the self signature in the key
417
 
    crtverify = ctypes.c_uint();
418
 
    gnutls.library.functions.gnutls_openpgp_crt_verify_self\
419
 
        (crt, 0, ctypes.byref(crtverify))
420
 
    if crtverify.value != 0:
421
 
        gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
422
 
        raise gnutls.errors.CertificateSecurityError("Verify failed")
 
285
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
 
286
        (crt,
 
287
         ctypes.byref(datum),
 
288
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
423
289
    # New buffer for the fingerprint
424
290
    buffer = ctypes.create_string_buffer(20)
425
291
    buffer_length = ctypes.c_size_t()
441
307
    Note: This will run in its own forked process."""
442
308
    
443
309
    def handle(self):
444
 
        logger.info(u"TCP connection from: %s",
 
310
        logger.debug(u"TCP connection from: %s",
445
311
                     unicode(self.client_address))
446
 
        session = gnutls.connection.ClientSession\
447
 
                  (self.request, gnutls.connection.X509Credentials())
448
 
        
449
 
        line = self.request.makefile().readline()
450
 
        logger.debug(u"Protocol version: %r", line)
451
 
        try:
452
 
            if int(line.strip().split()[0]) > 1:
453
 
                raise RuntimeError
454
 
        except (ValueError, IndexError, RuntimeError), error:
455
 
            logger.error(u"Unknown protocol version: %s", error)
456
 
            return
457
 
        
458
 
        # Note: gnutls.connection.X509Credentials is really a generic
459
 
        # GnuTLS certificate credentials object so long as no X.509
460
 
        # keys are added to it.  Therefore, we can use it here despite
461
 
        # using OpenPGP certificates.
 
312
        session = gnutls.connection.ClientSession(self.request,
 
313
                                                  gnutls.connection.\
 
314
                                                  X509Credentials())
462
315
        
463
316
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
464
317
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
465
318
        #                "+DHE-DSS"))
466
 
        priority = "NORMAL"             # Fallback default, since this
467
 
                                        # MUST be set.
468
 
        if self.server.settings["priority"]:
469
 
            priority = self.server.settings["priority"]
 
319
        priority = "SECURE256"
 
320
        
470
321
        gnutls.library.functions.gnutls_priority_set_direct\
471
322
            (session._c_object, priority, None);
472
323
        
473
324
        try:
474
325
            session.handshake()
475
326
        except gnutls.errors.GNUTLSError, error:
476
 
            logger.warning(u"Handshake failed: %s", error)
 
327
            logger.debug(u"Handshake failed: %s", error)
477
328
            # Do not run session.bye() here: the session is not
478
329
            # established.  Just abandon the request.
479
330
            return
480
331
        try:
481
332
            fpr = fingerprint(peer_certificate(session))
482
333
        except (TypeError, gnutls.errors.GNUTLSError), error:
483
 
            logger.warning(u"Bad certificate: %s", error)
 
334
            logger.debug(u"Bad certificate: %s", error)
484
335
            session.bye()
485
336
            return
486
337
        logger.debug(u"Fingerprint: %s", fpr)
487
338
        client = None
488
 
        for c in self.server.clients:
 
339
        for c in clients:
489
340
            if c.fingerprint == fpr:
490
341
                client = c
491
342
                break
492
 
        if not client:
493
 
            logger.warning(u"Client not found for fingerprint: %s",
494
 
                           fpr)
495
 
            session.bye()
496
 
            return
497
343
        # Have to check if client.still_valid(), since it is possible
498
344
        # that the client timed out while establishing the GnuTLS
499
345
        # session.
500
 
        if not client.still_valid():
501
 
            logger.warning(u"Client %(name)s is invalid",
502
 
                           vars(client))
 
346
        if (not client) or (not client.still_valid()):
 
347
            if client:
 
348
                logger.debug(u"Client %(name)s is invalid",
 
349
                             vars(client))
 
350
            else:
 
351
                logger.debug(u"Client not found for fingerprint: %s",
 
352
                             fpr)
503
353
            session.bye()
504
354
            return
505
355
        sent_size = 0
515
365
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
516
366
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
517
367
    Attributes:
518
 
        settings:       Server settings
 
368
        options:        Command line options
519
369
        clients:        Set() of Client objects
520
370
    """
521
371
    address_family = socket.AF_INET6
522
372
    def __init__(self, *args, **kwargs):
523
 
        if "settings" in kwargs:
524
 
            self.settings = kwargs["settings"]
525
 
            del kwargs["settings"]
 
373
        if "options" in kwargs:
 
374
            self.options = kwargs["options"]
 
375
            del kwargs["options"]
526
376
        if "clients" in kwargs:
527
377
            self.clients = kwargs["clients"]
528
378
            del kwargs["clients"]
531
381
        """This overrides the normal server_bind() function
532
382
        to bind to an interface if one was specified, and also NOT to
533
383
        bind to an address or port if they were not specified."""
534
 
        if self.settings["interface"]:
535
 
            # 25 is from /usr/include/asm-i486/socket.h
536
 
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
 
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
537
388
            try:
538
389
                self.socket.setsockopt(socket.SOL_SOCKET,
539
 
                                       SO_BINDTODEVICE,
540
 
                                       self.settings["interface"])
 
390
                                       socket.SO_BINDTODEVICE,
 
391
                                       self.options.interface)
541
392
            except socket.error, error:
542
393
                if error[0] == errno.EPERM:
543
 
                    logger.error(u"No permission to"
544
 
                                 u" bind to interface %s",
545
 
                                 self.settings["interface"])
 
394
                    logger.warning(u"No permission to"
 
395
                                   u" bind to interface %s",
 
396
                                   self.options.interface)
546
397
                else:
547
398
                    raise error
548
399
        # Only bind(2) the socket if we really need to.
551
402
                in6addr_any = "::"
552
403
                self.server_address = (in6addr_any,
553
404
                                       self.server_address[1])
554
 
            elif not self.server_address[1]:
 
405
            elif self.server_address[1] is None:
555
406
                self.server_address = (self.server_address[0],
556
407
                                       0)
557
 
#                 if self.settings["interface"]:
558
 
#                     self.server_address = (self.server_address[0],
559
 
#                                            0, # port
560
 
#                                            0, # flowinfo
561
 
#                                            if_nametoindex
562
 
#                                            (self.settings
563
 
#                                             ["interface"]))
564
408
            return super(type(self), self).server_bind()
565
409
 
566
410
 
577
421
    datetime.timedelta(1)
578
422
    >>> string_to_delta(u'1w')
579
423
    datetime.timedelta(7)
580
 
    >>> string_to_delta('5m 30s')
581
 
    datetime.timedelta(0, 330)
582
424
    """
583
 
    timevalue = datetime.timedelta(0)
584
 
    for s in interval.split():
585
 
        try:
586
 
            suffix=unicode(s[-1])
587
 
            value=int(s[:-1])
588
 
            if suffix == u"d":
589
 
                delta = datetime.timedelta(value)
590
 
            elif suffix == u"s":
591
 
                delta = datetime.timedelta(0, value)
592
 
            elif suffix == u"m":
593
 
                delta = datetime.timedelta(0, 0, 0, 0, value)
594
 
            elif suffix == u"h":
595
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, value)
596
 
            elif suffix == u"w":
597
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
598
 
            else:
599
 
                raise ValueError
600
 
        except (ValueError, IndexError):
 
425
    try:
 
426
        suffix=unicode(interval[-1])
 
427
        value=int(interval[:-1])
 
428
        if suffix == u"d":
 
429
            delta = datetime.timedelta(value)
 
430
        elif suffix == u"s":
 
431
            delta = datetime.timedelta(0, value)
 
432
        elif suffix == u"m":
 
433
            delta = datetime.timedelta(0, 0, 0, 0, value)
 
434
        elif suffix == u"h":
 
435
            delta = datetime.timedelta(0, 0, 0, 0, 0, value)
 
436
        elif suffix == u"w":
 
437
            delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
 
438
        else:
601
439
            raise ValueError
602
 
        timevalue += delta
603
 
    return timevalue
 
440
    except (ValueError, IndexError):
 
441
        raise ValueError
 
442
    return delta
 
443
 
 
444
 
 
445
def add_service():
 
446
    """From the Avahi server example code"""
 
447
    global group, serviceName, serviceType, servicePort, serviceTXT, \
 
448
           domain, host
 
449
    if group is None:
 
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)
 
458
    
 
459
    group.AddService(
 
460
            serviceInterface,           # interface
 
461
            avahi.PROTO_INET6,          # protocol
 
462
            dbus.UInt32(0),             # flags
 
463
            serviceName, serviceType,
 
464
            domain, host,
 
465
            dbus.UInt16(servicePort),
 
466
            avahi.string_array_to_txt_array(serviceTXT))
 
467
    group.Commit()
 
468
 
 
469
 
 
470
def remove_service():
 
471
    """From the Avahi server example code"""
 
472
    global group
 
473
    
 
474
    if not group is None:
 
475
        group.Reset()
604
476
 
605
477
 
606
478
def server_state_changed(state):
607
 
    """Derived from the Avahi example code"""
 
479
    """From the Avahi server example code"""
608
480
    if state == avahi.SERVER_COLLISION:
609
 
        logger.error(u"Zeroconf server name collision")
610
 
        service.remove()
 
481
        logger.warning(u"Server name collision")
 
482
        remove_service()
611
483
    elif state == avahi.SERVER_RUNNING:
612
 
        service.add()
 
484
        add_service()
613
485
 
614
486
 
615
487
def entry_group_state_changed(state, error):
616
 
    """Derived from the Avahi example code"""
617
 
    logger.debug(u"Avahi state change: %i", state)
 
488
    """From the Avahi server example code"""
 
489
    global serviceName, server, rename_count
 
490
    
 
491
    logger.debug(u"state change: %i", state)
618
492
    
619
493
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
620
 
        logger.debug(u"Zeroconf service established.")
 
494
        logger.debug(u"Service established.")
621
495
    elif state == avahi.ENTRY_GROUP_COLLISION:
622
 
        logger.warning(u"Zeroconf service name collision.")
623
 
        service.rename()
 
496
        
 
497
        rename_count = rename_count - 1
 
498
        if rename_count > 0:
 
499
            name = server.GetAlternativeServiceName(name)
 
500
            logger.warning(u"Service name collision, "
 
501
                           u"changing name to '%s' ...", name)
 
502
            remove_service()
 
503
            add_service()
 
504
            
 
505
        else:
 
506
            logger.error(u"No suitable service name found "
 
507
                         u"after %i retries, exiting.",
 
508
                         n_rename)
 
509
            main_loop.quit()
624
510
    elif state == avahi.ENTRY_GROUP_FAILURE:
625
 
        logger.critical(u"Avahi: Error in group state changed %s",
626
 
                        unicode(error))
627
 
        raise AvahiGroupError("State changed: %s", str(error))
 
511
        logger.error(u"Error in group state changed %s",
 
512
                     unicode(error))
 
513
        main_loop.quit()
 
514
        return
 
515
 
628
516
 
629
517
def if_nametoindex(interface):
630
 
    """Call the C function if_nametoindex(), or equivalent"""
631
 
    global if_nametoindex
 
518
    """Call the C function if_nametoindex()"""
632
519
    try:
633
 
        if "ctypes.util" not in sys.modules:
634
 
            import ctypes.util
635
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
636
 
            (ctypes.util.find_library("c")).if_nametoindex
 
520
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
 
521
        return libc.if_nametoindex(interface)
637
522
    except (OSError, AttributeError):
638
523
        if "struct" not in sys.modules:
639
524
            import struct
640
525
        if "fcntl" not in sys.modules:
641
526
            import fcntl
642
 
        def if_nametoindex(interface):
643
 
            "Get an interface index the hard way, i.e. using fcntl()"
644
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
645
 
            s = socket.socket()
646
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
647
 
                                struct.pack("16s16x", interface))
648
 
            s.close()
649
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
650
 
            return interface_index
651
 
    return if_nametoindex(interface)
652
 
 
653
 
 
654
 
def daemon(nochdir = False, noclose = False):
655
 
    """See daemon(3).  Standard BSD Unix function.
656
 
    This should really exist as os.daemon, but it doesn't (yet)."""
657
 
    if os.fork():
658
 
        sys.exit()
659
 
    os.setsid()
660
 
    if not nochdir:
661
 
        os.chdir("/")
662
 
    if os.fork():
663
 
        sys.exit()
664
 
    if not noclose:
665
 
        # Close all standard open file descriptors
666
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
667
 
        if not stat.S_ISCHR(os.fstat(null).st_mode):
668
 
            raise OSError(errno.ENODEV,
669
 
                          "/dev/null not a character device")
670
 
        os.dup2(null, sys.stdin.fileno())
671
 
        os.dup2(null, sys.stdout.fileno())
672
 
        os.dup2(null, sys.stderr.fileno())
673
 
        if null > 2:
674
 
            os.close(null)
675
 
 
676
 
 
677
 
def main():
678
 
    global main_loop_started
679
 
    main_loop_started = False
680
 
    
681
 
    parser = OptionParser(version = "%%prog %s" % version)
 
527
        SIOCGIFINDEX = 0x8933      # From /usr/include/linux/sockios.h
 
528
        s = socket.socket()
 
529
        ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
 
530
                            struct.pack("16s16x", interface))
 
531
        s.close()
 
532
        interface_index = struct.unpack("I", ifreq[16:20])[0]
 
533
        return interface_index
 
534
 
 
535
 
 
536
if __name__ == '__main__':
 
537
    parser = OptionParser()
682
538
    parser.add_option("-i", "--interface", type="string",
683
 
                      metavar="IF", help="Bind to interface IF")
684
 
    parser.add_option("-a", "--address", type="string",
685
 
                      help="Address to listen for requests on")
686
 
    parser.add_option("-p", "--port", type="int",
 
539
                      default=None, metavar="IF",
 
540
                      help="Bind to interface IF")
 
541
    parser.add_option("--cert", type="string", default="cert.pem",
 
542
                      metavar="FILE",
 
543
                      help="Public key certificate PEM file to use")
 
544
    parser.add_option("--key", type="string", default="key.pem",
 
545
                      metavar="FILE",
 
546
                      help="Private key PEM file to use")
 
547
    parser.add_option("--ca", type="string", default="ca.pem",
 
548
                      metavar="FILE",
 
549
                      help="Certificate Authority certificate PEM file to use")
 
550
    parser.add_option("--crl", type="string", default="crl.pem",
 
551
                      metavar="FILE",
 
552
                      help="Certificate Revokation List PEM file to use")
 
553
    parser.add_option("-p", "--port", type="int", default=None,
687
554
                      help="Port number to receive requests on")
 
555
    parser.add_option("--timeout", type="string", # Parsed later
 
556
                      default="1h",
 
557
                      help="Amount of downtime allowed for clients")
 
558
    parser.add_option("--interval", type="string", # Parsed later
 
559
                      default="5m",
 
560
                      help="How often to check that a client is up")
688
561
    parser.add_option("--check", action="store_true", default=False,
689
562
                      help="Run self-test")
690
 
    parser.add_option("--debug", action="store_true",
691
 
                      help="Debug mode; run in foreground and log to"
692
 
                      " terminal")
693
 
    parser.add_option("--priority", type="string", help="GnuTLS"
694
 
                      " priority string (see GnuTLS documentation)")
695
 
    parser.add_option("--servicename", type="string", metavar="NAME",
696
 
                      help="Zeroconf service name")
697
 
    parser.add_option("--configdir", type="string",
698
 
                      default="/etc/mandos", metavar="DIR",
699
 
                      help="Directory to search for configuration"
700
 
                      " files")
 
563
    parser.add_option("--debug", action="store_true", default=False,
 
564
                      help="Debug mode")
701
565
    (options, args) = parser.parse_args()
702
566
    
703
567
    if options.check:
705
569
        doctest.testmod()
706
570
        sys.exit()
707
571
    
708
 
    # Default values for config file for server-global settings
709
 
    server_defaults = { "interface": "",
710
 
                        "address": "",
711
 
                        "port": "",
712
 
                        "debug": "False",
713
 
                        "priority":
714
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
715
 
                        "servicename": "Mandos",
716
 
                        }
717
 
    
718
 
    # Parse config file for server-global settings
719
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
720
 
    del server_defaults
721
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
722
 
    # Convert the SafeConfigParser object to a dict
723
 
    server_settings = server_config.defaults()
724
 
    # Use getboolean on the boolean config option
725
 
    server_settings["debug"] = server_config.getboolean\
726
 
                               ("DEFAULT", "debug")
727
 
    del server_config
728
 
    
729
 
    # Override the settings from the config file with command line
730
 
    # options, if set.
731
 
    for option in ("interface", "address", "port", "debug",
732
 
                   "priority", "servicename", "configdir"):
733
 
        value = getattr(options, option)
734
 
        if value is not None:
735
 
            server_settings[option] = value
736
 
    del options
737
 
    # Now we have our good server settings in "server_settings"
738
 
    
739
 
    debug = server_settings["debug"]
740
 
    
741
 
    if not debug:
742
 
        syslogger.setLevel(logging.WARNING)
743
 
        console.setLevel(logging.WARNING)
744
 
    
745
 
    if server_settings["servicename"] != "Mandos":
746
 
        syslogger.setFormatter(logging.Formatter\
747
 
                               ('Mandos (%s): %%(levelname)s:'
748
 
                                ' %%(message)s'
749
 
                                % server_settings["servicename"]))
750
 
    
751
 
    # Parse config file with clients
752
 
    client_defaults = { "timeout": "1h",
753
 
                        "interval": "5m",
754
 
                        "checker": "fping -q -- %(host)s",
755
 
                        "host": "",
756
 
                        }
757
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
758
 
    client_config.read(os.path.join(server_settings["configdir"],
759
 
                                    "clients.conf"))
760
 
    
761
 
    global service
762
 
    service = AvahiService(name = server_settings["servicename"],
763
 
                           type = "_mandos._tcp", );
764
 
    if server_settings["interface"]:
765
 
        service.interface = if_nametoindex\
766
 
                            (server_settings["interface"])
767
 
    
768
 
    global main_loop
769
 
    global bus
770
 
    global server
771
 
    # From the Avahi example code
 
572
    # Parse the time arguments
 
573
    try:
 
574
        options.timeout = string_to_delta(options.timeout)
 
575
    except ValueError:
 
576
        parser.error("option --timeout: Unparseable time")
 
577
    try:
 
578
        options.interval = string_to_delta(options.interval)
 
579
    except ValueError:
 
580
        parser.error("option --interval: Unparseable time")
 
581
    
 
582
    # Parse config file
 
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")
 
587
    
 
588
    # From the Avahi server example code
772
589
    DBusGMainLoop(set_as_default=True )
773
590
    main_loop = gobject.MainLoop()
774
591
    bus = dbus.SystemBus()
775
 
    server = dbus.Interface(bus.get_object(avahi.DBUS_NAME,
776
 
                                           avahi.DBUS_PATH_SERVER),
777
 
                            avahi.DBUS_INTERFACE_SERVER)
 
592
    server = dbus.Interface(
 
593
            bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
 
594
            avahi.DBUS_INTERFACE_SERVER )
778
595
    # End of Avahi example code
779
596
    
 
597
    debug = options.debug
 
598
    
780
599
    clients = Set()
781
600
    def remove_from_clients(client):
782
601
        clients.remove(client)
783
602
        if not clients:
784
 
            logger.critical(u"No clients left, exiting")
785
 
            sys.exit()
 
603
            logger.debug(u"No clients left, exiting")
 
604
            main_loop.quit()
786
605
    
787
 
    clients.update(Set(Client(name = section,
 
606
    clients.update(Set(Client(name=section, options=options,
788
607
                              stop_hook = remove_from_clients,
789
 
                              config
790
 
                              = dict(client_config.items(section)))
 
608
                              **(dict(client_config\
 
609
                                      .items(section))))
791
610
                       for section in client_config.sections()))
792
 
    if not clients:
793
 
        logger.critical(u"No clients defined")
794
 
        sys.exit(1)
795
 
    
796
 
    if debug:
797
 
        # Redirect stdin so all checkers get /dev/null
798
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
799
 
        os.dup2(null, sys.stdin.fileno())
800
 
        if null > 2:
801
 
            os.close(null)
802
 
    else:
803
 
        # No console logging
804
 
        logger.removeHandler(console)
805
 
        # Close all input and output, do double fork, etc.
806
 
        daemon()
807
 
    
808
 
    pidfilename = "/var/run/mandos/mandos.pid"
809
 
    pid = os.getpid()
810
 
    try:
811
 
        pidfile = open(pidfilename, "w")
812
 
        pidfile.write(str(pid) + "\n")
813
 
        pidfile.close()
814
 
        del pidfile
815
 
    except IOError, err:
816
 
        logger.error(u"Could not write %s file with PID %d",
817
 
                     pidfilename, os.getpid())
818
 
    
819
 
    def cleanup():
820
 
        "Cleanup function; run on exit"
821
 
        global group
822
 
        # From the Avahi example code
823
 
        if not group is None:
824
 
            group.Free()
825
 
            group = None
826
 
        # End of Avahi example code
827
 
        
828
 
        while clients:
829
 
            client = clients.pop()
830
 
            client.stop_hook = None
831
 
            client.stop()
832
 
    
833
 
    atexit.register(cleanup)
834
 
    
835
 
    if not debug:
836
 
        signal.signal(signal.SIGINT, signal.SIG_IGN)
837
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
838
 
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
839
 
    
840
611
    for client in clients:
841
612
        client.start()
842
613
    
843
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
844
 
                                 server_settings["port"]),
 
614
    tcp_server = IPv6_TCPServer((None, options.port),
845
615
                                tcp_handler,
846
 
                                settings=server_settings,
 
616
                                options=options,
847
617
                                clients=clients)
848
 
    # Find out what port we got
849
 
    service.port = tcp_server.socket.getsockname()[1]
850
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
851
 
                u" scope_id %d" % tcp_server.socket.getsockname())
852
 
    
853
 
    #service.interface = tcp_server.socket.getsockname()[3]
854
 
    
 
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)
 
621
    
 
622
    if options.interface is not None:
 
623
        serviceInterface = if_nametoindex(options.interface)
 
624
    
 
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
 
629
    
 
630
    gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
 
631
                         lambda *args, **kwargs:
 
632
                         tcp_server.handle_request(*args[2:],
 
633
                                                   **kwargs) or True)
855
634
    try:
856
 
        # From the Avahi example code
857
 
        server.connect_to_signal("StateChanged", server_state_changed)
858
 
        try:
859
 
            server_state_changed(server.GetState())
860
 
        except dbus.exceptions.DBusException, error:
861
 
            logger.critical(u"DBusException: %s", error)
862
 
            sys.exit(1)
863
 
        # End of Avahi example code
864
 
        
865
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
866
 
                             lambda *args, **kwargs:
867
 
                             tcp_server.handle_request\
868
 
                             (*args[2:], **kwargs) or True)
869
 
        
870
 
        logger.debug(u"Starting main loop")
871
 
        main_loop_started = True
872
635
        main_loop.run()
873
 
    except AvahiError, error:
874
 
        logger.critical(u"AvahiError: %s" + unicode(error))
875
 
        sys.exit(1)
876
636
    except KeyboardInterrupt:
877
 
        if debug:
878
 
            print
 
637
        print
 
638
    
 
639
    # Cleanup here
879
640
 
880
 
if __name__ == '__main__':
881
 
    main()
 
641
    # From the Avahi server example code
 
642
    if not group is None:
 
643
        group.Free()
 
644
    # End of Avahi example code
 
645
    
 
646
    for client in clients:
 
647
        client.stop_hook = None
 
648
        client.stop()