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  • Committer: Teddy Hogeborn
  • Date: 2008-07-19 18:43:24 UTC
  • Revision ID: teddy@fukt.bsnet.se-20080719184324-iwhoa5in75xa0u2u
* mandos-clients.conf ([foo]/dn, [foo]/password, [braxen_client]/dn,
                       [braxen_client]/password): Removed.
  ([foo]/fingerprint, [braxen_client]/fingerprint): New.
  ([foo]/checker): New.
  ([foo]/secfile): New.
  ([braxen_client]/secret): New.

* server.py: New "--debug" option to set debug flag.  Removed "cert",
             "key", "ca", "crl", and "cred" variables.  Added default
             value for "checker" config file setting.  Do not pass
             credentials to IPv6_TCPServer constructor.
  (debug): New global debug flag.  Used by most debugging output code.
  (Client.__init__): Keyword argument "dn" replaced by "fingerprint",
                     "password" renamed to "secret", and "passfile"
                     renamed to "secfile".  New keyword argument
                     "checker". All callers changed.
  (Client.dn): Removed.
  (Client.fingerprint): New.
  (Client.password): Renamed to "secret"; all users changed.
  (Client.passfile): Renamed to "secfile"; all users changed.
  (Client.timeout, Client.interval): Changed to be properties; now
                                     automatically updates the
                                     "_timeout_milliseconds" and
                                     "_interval_milliseconds" values.
  (Client.timeout_milliseconds): Renamed to "_timeout_milliseconds".
  (Client.interval_milliseconds): Renamed to "_interval_milliseconds".
  (Client.check_command): New.
  (Client.start_checker): Use the new "check_command" attribute.
  (peer_certificate, fingerprint): New functions.

  (tcp_handler.handle): Use ClientSession with empty credentials
                        object instead of ServerSession.  Set gnutls
                        priority string.  Do not verify peer.  Use
                        fingerprint instead of DN when searching for
                        clients.  Bug fix: Loop sending data so even large
                        secret data strings are sent.
  (IPv6_TCPServer.credentials): Removed.
  (if_nametoindex): Do not import ctypes since that is now imported
                    globally.

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server.py
1
1
#!/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 <http://www.gnu.org/licenses/>.
28
 
# 
29
 
# Contact the authors at <mandos@fukt.bsnet.se>.
30
 
# 
31
2
 
32
3
from __future__ import division
33
4
 
50
21
import signal
51
22
from sets import Set
52
23
import subprocess
53
 
import atexit
54
 
import stat
55
 
import logging
56
 
import logging.handlers
57
24
 
58
25
import dbus
59
26
import gobject
61
28
from dbus.mainloop.glib import DBusGMainLoop
62
29
import ctypes
63
30
 
64
 
version = "1.0"
65
 
 
66
 
logger = logging.Logger('mandos')
67
 
syslogger = logging.handlers.SysLogHandler\
68
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
69
 
             address = "/dev/log")
70
 
syslogger.setFormatter(logging.Formatter\
71
 
                        ('Mandos: %(levelname)s: %(message)s'))
72
 
logger.addHandler(syslogger)
73
 
 
74
 
console = logging.StreamHandler()
75
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
76
 
                                       ' %(message)s'))
77
 
logger.addHandler(console)
78
 
 
79
 
class AvahiError(Exception):
80
 
    def __init__(self, value):
81
 
        self.value = value
82
 
    def __str__(self):
83
 
        return repr(self.value)
84
 
 
85
 
class AvahiServiceError(AvahiError):
86
 
    pass
87
 
 
88
 
class AvahiGroupError(AvahiError):
89
 
    pass
90
 
 
91
 
 
92
 
class AvahiService(object):
93
 
    """An Avahi (Zeroconf) service.
94
 
    Attributes:
95
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
96
 
               Used to optionally bind to the specified interface.
97
 
    name: string; Example: 'Mandos'
98
 
    type: string; Example: '_mandos._tcp'.
99
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
100
 
    port: integer; what port to announce
101
 
    TXT: list of strings; TXT record for the service
102
 
    domain: string; Domain to publish on, default to .local if empty.
103
 
    host: string; Host to publish records for, default is localhost
104
 
    max_renames: integer; maximum number of renames
105
 
    rename_count: integer; counter so we only rename after collisions
106
 
                  a sensible number of times
107
 
    """
108
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
109
 
                 type = None, port = None, TXT = None, domain = "",
110
 
                 host = "", max_renames = 32768):
111
 
        self.interface = interface
112
 
        self.name = name
113
 
        self.type = type
114
 
        self.port = port
115
 
        if TXT is None:
116
 
            self.TXT = []
117
 
        else:
118
 
            self.TXT = TXT
119
 
        self.domain = domain
120
 
        self.host = host
121
 
        self.rename_count = 0
122
 
    def rename(self):
123
 
        """Derived from the Avahi example code"""
124
 
        if self.rename_count >= self.max_renames:
125
 
            logger.critical(u"No suitable service name found after %i"
126
 
                            u" retries, exiting.", rename_count)
127
 
            raise AvahiServiceError("Too many renames")
128
 
        name = server.GetAlternativeServiceName(name)
129
 
        logger.error(u"Changing name to %r ...", name)
130
 
        syslogger.setFormatter(logging.Formatter\
131
 
                               ('Mandos (%s): %%(levelname)s:'
132
 
                               ' %%(message)s' % name))
133
 
        self.remove()
134
 
        self.add()
135
 
        self.rename_count += 1
136
 
    def remove(self):
137
 
        """Derived from the Avahi example code"""
138
 
        if group is not None:
139
 
            group.Reset()
140
 
    def add(self):
141
 
        """Derived from the Avahi example code"""
142
 
        global group
143
 
        if group is None:
144
 
            group = dbus.Interface\
145
 
                    (bus.get_object(avahi.DBUS_NAME,
146
 
                                    server.EntryGroupNew()),
147
 
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
148
 
            group.connect_to_signal('StateChanged',
149
 
                                    entry_group_state_changed)
150
 
        logger.debug(u"Adding service '%s' of type '%s' ...",
151
 
                     service.name, service.type)
152
 
        group.AddService(
153
 
                self.interface,         # interface
154
 
                avahi.PROTO_INET6,      # protocol
155
 
                dbus.UInt32(0),         # flags
156
 
                self.name, self.type,
157
 
                self.domain, self.host,
158
 
                dbus.UInt16(self.port),
159
 
                avahi.string_array_to_txt_array(self.TXT))
160
 
        group.Commit()
161
 
 
162
 
# From the Avahi example code:
163
 
group = None                            # our entry group
 
31
# This variable is used to optionally bind to a specified interface.
 
32
# It is a global variable to fit in with the other variables from the
 
33
# Avahi server example code.
 
34
serviceInterface = avahi.IF_UNSPEC
 
35
# From the Avahi server example code:
 
36
serviceName = "Mandos"
 
37
serviceType = "_mandos._tcp" # http://www.dns-sd.org/ServiceTypes.html
 
38
servicePort = None                      # Not known at startup
 
39
serviceTXT = []                         # TXT record for the service
 
40
domain = ""                  # Domain to publish on, default to .local
 
41
host = ""          # Host to publish records for, default to localhost
 
42
group = None #our entry group
 
43
rename_count = 12       # Counter so we only rename after collisions a
 
44
                        # sensible number of times
164
45
# End of Avahi example code
165
46
 
166
47
 
171
52
    fingerprint: string (40 or 32 hexadecimal digits); used to
172
53
                 uniquely identify the client
173
54
    secret:    bytestring; sent verbatim (over TLS) to client
174
 
    host:      string; available for use by the checker command
175
 
    created:   datetime.datetime(); object creation, not client host
176
 
    last_checked_ok: datetime.datetime() or None if not yet checked OK
177
 
    timeout:   datetime.timedelta(); How long from last_checked_ok
178
 
                                     until this client is invalid
 
55
    fqdn:      string (FQDN); available for use by the checker command
 
56
    created:   datetime.datetime()
 
57
    last_seen: datetime.datetime() or None if not yet seen
 
58
    timeout:   datetime.timedelta(); How long from last_seen until
 
59
                                     this client is invalid
179
60
    interval:  datetime.timedelta(); How often to start a new checker
180
61
    stop_hook: If set, called by stop() as stop_hook(self)
181
62
    checker:   subprocess.Popen(); a running checker process used
182
63
                                   to see if the client lives.
183
 
                                   'None' if no process is running.
 
64
                                   Is None if no process is running.
184
65
    checker_initiator_tag: a gobject event source tag, or None
185
66
    stop_initiator_tag:    - '' -
186
67
    checker_callback_tag:  - '' -
187
68
    checker_command: string; External command which is run to check if
188
 
                     client lives.  %() expansions are done at
 
69
                     client lives.  %()s expansions are done at
189
70
                     runtime with vars(self) as dict, so that for
190
71
                     instance %(name)s can be used in the command.
191
72
    Private attibutes:
192
73
    _timeout: Real variable for 'timeout'
193
74
    _interval: Real variable for 'interval'
194
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
 
75
    _timeout_milliseconds: Used by gobject.timeout_add()
195
76
    _interval_milliseconds: - '' -
196
77
    """
197
78
    def _set_timeout(self, timeout):
217
98
    interval = property(lambda self: self._interval,
218
99
                        _set_interval)
219
100
    del _set_interval
220
 
    def __init__(self, name = None, stop_hook=None, config={}):
221
 
        """Note: the 'checker' key in 'config' sets the
222
 
        'checker_command' attribute and *not* the 'checker'
223
 
        attribute."""
 
101
    def __init__(self, name=None, options=None, stop_hook=None,
 
102
                 fingerprint=None, secret=None, secfile=None, fqdn=None,
 
103
                 timeout=None, interval=-1, checker=None):
224
104
        self.name = name
225
 
        logger.debug(u"Creating client %r", self.name)
226
 
        # Uppercase and remove spaces from fingerprint for later
227
 
        # comparison purposes with return value from the fingerprint()
228
 
        # function
229
 
        self.fingerprint = config["fingerprint"].upper()\
230
 
                           .replace(u" ", u"")
231
 
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
232
 
        if "secret" in config:
233
 
            self.secret = config["secret"].decode(u"base64")
234
 
        elif "secfile" in config:
235
 
            sf = open(config["secfile"])
 
105
        # Uppercase and remove spaces from fingerprint
 
106
        # for later comparison purposes with return value of
 
107
        # the fingerprint() function
 
108
        self.fingerprint = fingerprint.upper().replace(u" ", u"")
 
109
        if secret:
 
110
            self.secret = secret.decode(u"base64")
 
111
        elif secfile:
 
112
            sf = open(secfile)
236
113
            self.secret = sf.read()
237
114
            sf.close()
238
115
        else:
239
 
            raise TypeError(u"No secret or secfile for client %s"
240
 
                            % self.name)
241
 
        self.host = config.get("host", "")
 
116
            raise RuntimeError(u"No secret or secfile for client %s"
 
117
                               % self.name)
 
118
        self.fqdn = fqdn                # string
242
119
        self.created = datetime.datetime.now()
243
 
        self.last_checked_ok = None
244
 
        self.timeout = string_to_delta(config["timeout"])
245
 
        self.interval = string_to_delta(config["interval"])
 
120
        self.last_seen = None
 
121
        if timeout is None:
 
122
            timeout = options.timeout
 
123
        self.timeout = timeout
 
124
        if interval == -1:
 
125
            interval = options.interval
 
126
        else:
 
127
            interval = string_to_delta(interval)
 
128
        self.interval = interval
246
129
        self.stop_hook = stop_hook
247
130
        self.checker = None
248
131
        self.checker_initiator_tag = None
249
132
        self.stop_initiator_tag = None
250
133
        self.checker_callback_tag = None
251
 
        self.check_command = config["checker"]
 
134
        self.check_command = checker
252
135
    def start(self):
253
 
        """Start this client's checker and timeout hooks"""
 
136
        """Start this clients checker and timeout hooks"""
254
137
        # Schedule a new checker to be started an 'interval' from now,
255
138
        # and every interval from then on.
256
139
        self.checker_initiator_tag = gobject.timeout_add\
264
147
                                   self.stop)
265
148
    def stop(self):
266
149
        """Stop this client.
267
 
        The possibility that a client might be restarted is left open,
268
 
        but not currently used."""
269
 
        # If this client doesn't have a secret, it is already stopped.
270
 
        if hasattr(self, "secret") and self.secret:
271
 
            logger.info(u"Stopping client %s", self.name)
272
 
            self.secret = None
273
 
        else:
274
 
            return False
275
 
        if getattr(self, "stop_initiator_tag", False):
 
150
        The possibility that this client might be restarted is left
 
151
        open, but not currently used."""
 
152
        if debug:
 
153
            sys.stderr.write(u"Stopping client %s\n" % self.name)
 
154
        self.secret = None
 
155
        if self.stop_initiator_tag:
276
156
            gobject.source_remove(self.stop_initiator_tag)
277
157
            self.stop_initiator_tag = None
278
 
        if getattr(self, "checker_initiator_tag", False):
 
158
        if self.checker_initiator_tag:
279
159
            gobject.source_remove(self.checker_initiator_tag)
280
160
            self.checker_initiator_tag = None
281
161
        self.stop_checker()
284
164
        # Do not run this again if called by a gobject.timeout_add
285
165
        return False
286
166
    def __del__(self):
287
 
        self.stop_hook = None
288
 
        self.stop()
 
167
        # Some code duplication here and in stop()
 
168
        if hasattr(self, "stop_initiator_tag") \
 
169
               and self.stop_initiator_tag:
 
170
            gobject.source_remove(self.stop_initiator_tag)
 
171
            self.stop_initiator_tag = None
 
172
        if hasattr(self, "checker_initiator_tag") \
 
173
               and self.checker_initiator_tag:
 
174
            gobject.source_remove(self.checker_initiator_tag)
 
175
            self.checker_initiator_tag = None
 
176
        self.stop_checker()
289
177
    def checker_callback(self, pid, condition):
290
178
        """The checker has completed, so take appropriate actions."""
291
179
        now = datetime.datetime.now()
292
 
        self.checker_callback_tag = None
293
 
        self.checker = None
294
180
        if os.WIFEXITED(condition) \
295
181
               and (os.WEXITSTATUS(condition) == 0):
296
 
            logger.info(u"Checker for %(name)s succeeded",
297
 
                        vars(self))
298
 
            self.last_checked_ok = now
 
182
            if debug:
 
183
                sys.stderr.write(u"Checker for %(name)s succeeded\n"
 
184
                                 % vars(self))
 
185
            self.last_seen = now
299
186
            gobject.source_remove(self.stop_initiator_tag)
300
187
            self.stop_initiator_tag = gobject.timeout_add\
301
188
                                      (self._timeout_milliseconds,
302
189
                                       self.stop)
303
 
        elif not os.WIFEXITED(condition):
304
 
            logger.warning(u"Checker for %(name)s crashed?",
305
 
                           vars(self))
306
 
        else:
307
 
            logger.info(u"Checker for %(name)s failed",
308
 
                        vars(self))
 
190
        elif debug:
 
191
            if not os.WIFEXITED(condition):
 
192
                sys.stderr.write(u"Checker for %(name)s crashed?\n"
 
193
                                 % vars(self))
 
194
            else:
 
195
                sys.stderr.write(u"Checker for %(name)s failed\n"
 
196
                                 % vars(self))
 
197
        self.checker = None
 
198
        self.checker_callback_tag = None
309
199
    def start_checker(self):
310
200
        """Start a new checker subprocess if one is not running.
311
201
        If a checker already exists, leave it running and do
312
202
        nothing."""
313
 
        # The reason for not killing a running checker is that if we
314
 
        # did that, then if a checker (for some reason) started
315
 
        # running slowly and taking more than 'interval' time, the
316
 
        # client would inevitably timeout, since no checker would get
317
 
        # a chance to run to completion.  If we instead leave running
318
 
        # checkers alone, the checker would have to take more time
319
 
        # than 'timeout' for the client to be declared invalid, which
320
 
        # is as it should be.
321
203
        if self.checker is None:
 
204
            if debug:
 
205
                sys.stderr.write(u"Starting checker for %s\n"
 
206
                                 % self.name)
322
207
            try:
323
 
                # In case check_command has exactly one % operator
324
 
                command = self.check_command % self.host
 
208
                command = self.check_command % self.fqdn
325
209
            except TypeError:
326
 
                # Escape attributes for the shell
327
210
                escaped_attrs = dict((key, re.escape(str(val)))
328
211
                                     for key, val in
329
212
                                     vars(self).iteritems())
330
 
                try:
331
 
                    command = self.check_command % escaped_attrs
332
 
                except TypeError, error:
333
 
                    logger.error(u'Could not format string "%s":'
334
 
                                 u' %s', self.check_command, error)
335
 
                    return True # Try again later
 
213
                command = self.check_command % escaped_attrs
336
214
            try:
337
 
                logger.info(u"Starting checker %r for %s",
338
 
                            command, self.name)
339
 
                self.checker = subprocess.Popen(command,
340
 
                                                close_fds=True,
341
 
                                                shell=True, cwd="/")
342
 
                self.checker_callback_tag = gobject.child_watch_add\
343
 
                                            (self.checker.pid,
344
 
                                             self.checker_callback)
 
215
                self.checker = subprocess.\
 
216
                               Popen(command,
 
217
                                     stdout=subprocess.PIPE,
 
218
                                     close_fds=True, shell=True,
 
219
                                     cwd="/")
 
220
                self.checker_callback_tag = gobject.\
 
221
                                            child_watch_add(self.checker.pid,
 
222
                                                            self.\
 
223
                                                            checker_callback)
345
224
            except subprocess.OSError, error:
346
 
                logger.error(u"Failed to start subprocess: %s",
347
 
                             error)
 
225
                sys.stderr.write(u"Failed to start subprocess: %s\n"
 
226
                                 % error)
348
227
        # Re-run this periodically if run by gobject.timeout_add
349
228
        return True
350
229
    def stop_checker(self):
351
230
        """Force the checker process, if any, to stop."""
352
 
        if self.checker_callback_tag:
353
 
            gobject.source_remove(self.checker_callback_tag)
354
 
            self.checker_callback_tag = None
355
 
        if getattr(self, "checker", None) is None:
 
231
        if not hasattr(self, "checker") or self.checker is None:
356
232
            return
357
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
358
 
        try:
359
 
            os.kill(self.checker.pid, signal.SIGTERM)
360
 
            #os.sleep(0.5)
361
 
            #if self.checker.poll() is None:
362
 
            #    os.kill(self.checker.pid, signal.SIGKILL)
363
 
        except OSError, error:
364
 
            if error.errno != errno.ESRCH: # No such process
365
 
                raise
 
233
        gobject.source_remove(self.checker_callback_tag)
 
234
        self.checker_callback_tag = None
 
235
        os.kill(self.checker.pid, signal.SIGTERM)
 
236
        if self.checker.poll() is None:
 
237
            os.kill(self.checker.pid, signal.SIGKILL)
366
238
        self.checker = None
367
 
    def still_valid(self):
 
239
    def still_valid(self, now=None):
368
240
        """Has the timeout not yet passed for this client?"""
369
 
        now = datetime.datetime.now()
370
 
        if self.last_checked_ok is None:
 
241
        if now is None:
 
242
            now = datetime.datetime.now()
 
243
        if self.last_seen is None:
371
244
            return now < (self.created + self.timeout)
372
245
        else:
373
 
            return now < (self.last_checked_ok + self.timeout)
 
246
            return now < (self.last_seen + self.timeout)
374
247
 
375
248
 
376
249
def peer_certificate(session):
377
 
    "Return the peer's OpenPGP certificate as a bytestring"
378
250
    # If not an OpenPGP certificate...
379
251
    if gnutls.library.functions.gnutls_certificate_type_get\
380
252
            (session._c_object) \
391
263
 
392
264
 
393
265
def fingerprint(openpgp):
394
 
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
 
266
    # New empty GnuTLS certificate
 
267
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
268
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
269
        (ctypes.byref(crt))
395
270
    # New GnuTLS "datum" with the OpenPGP public key
396
271
    datum = gnutls.library.types.gnutls_datum_t\
397
272
        (ctypes.cast(ctypes.c_char_p(openpgp),
398
273
                     ctypes.POINTER(ctypes.c_ubyte)),
399
274
         ctypes.c_uint(len(openpgp)))
400
 
    # New empty GnuTLS certificate
401
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
402
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
403
 
        (ctypes.byref(crt))
404
275
    # Import the OpenPGP public key into the certificate
405
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
406
 
                    (crt, ctypes.byref(datum),
407
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
 
276
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
 
277
        (crt,
 
278
         ctypes.byref(datum),
 
279
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
408
280
    # New buffer for the fingerprint
409
281
    buffer = ctypes.create_string_buffer(20)
410
282
    buffer_length = ctypes.c_size_t()
426
298
    Note: This will run in its own forked process."""
427
299
    
428
300
    def handle(self):
429
 
        logger.info(u"TCP connection from: %s",
430
 
                     unicode(self.client_address))
431
 
        session = gnutls.connection.ClientSession\
432
 
                  (self.request, gnutls.connection.X509Credentials())
433
 
        
434
 
        line = self.request.makefile().readline()
435
 
        logger.debug(u"Protocol version: %r", line)
436
 
        try:
437
 
            if int(line.strip().split()[0]) > 1:
438
 
                raise RuntimeError
439
 
        except (ValueError, IndexError, RuntimeError), error:
440
 
            logger.error(u"Unknown protocol version: %s", error)
441
 
            return
442
 
        
443
 
        # Note: gnutls.connection.X509Credentials is really a generic
444
 
        # GnuTLS certificate credentials object so long as no X.509
445
 
        # keys are added to it.  Therefore, we can use it here despite
446
 
        # using OpenPGP certificates.
 
301
        if debug:
 
302
            sys.stderr.write(u"TCP request came\n")
 
303
            sys.stderr.write(u"Request: %s\n" % self.request)
 
304
            sys.stderr.write(u"Client Address: %s\n"
 
305
                             % unicode(self.client_address))
 
306
            sys.stderr.write(u"Server: %s\n" % self.server)
 
307
        session = gnutls.connection.ClientSession(self.request,
 
308
                                                  gnutls.connection.\
 
309
                                                  X509Credentials())
447
310
        
448
311
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
449
312
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
450
313
        #                "+DHE-DSS"))
451
 
        priority = "NORMAL"             # Fallback default, since this
452
 
                                        # MUST be set.
453
 
        if self.server.settings["priority"]:
454
 
            priority = self.server.settings["priority"]
 
314
        priority = "SECURE256"
 
315
        
455
316
        gnutls.library.functions.gnutls_priority_set_direct\
456
317
            (session._c_object, priority, None);
457
318
        
458
319
        try:
459
320
            session.handshake()
460
321
        except gnutls.errors.GNUTLSError, error:
461
 
            logger.warning(u"Handshake failed: %s", error)
 
322
            if debug:
 
323
                sys.stderr.write(u"Handshake failed: %s\n" % error)
462
324
            # Do not run session.bye() here: the session is not
463
325
            # established.  Just abandon the request.
464
326
            return
465
327
        try:
466
328
            fpr = fingerprint(peer_certificate(session))
467
329
        except (TypeError, gnutls.errors.GNUTLSError), error:
468
 
            logger.warning(u"Bad certificate: %s", error)
 
330
            if debug:
 
331
                sys.stderr.write(u"Bad certificate: %s\n" % error)
469
332
            session.bye()
470
333
            return
471
 
        logger.debug(u"Fingerprint: %s", fpr)
 
334
        if debug:
 
335
            sys.stderr.write(u"Fingerprint: %s\n" % fpr)
472
336
        client = None
473
 
        for c in self.server.clients:
 
337
        for c in clients:
474
338
            if c.fingerprint == fpr:
475
339
                client = c
476
340
                break
477
 
        if not client:
478
 
            logger.warning(u"Client not found for fingerprint: %s",
479
 
                           fpr)
480
 
            session.bye()
481
 
            return
482
341
        # Have to check if client.still_valid(), since it is possible
483
342
        # that the client timed out while establishing the GnuTLS
484
343
        # session.
485
 
        if not client.still_valid():
486
 
            logger.warning(u"Client %(name)s is invalid",
487
 
                           vars(client))
 
344
        if (not client) or (not client.still_valid()):
 
345
            if debug:
 
346
                if client:
 
347
                    sys.stderr.write(u"Client %(name)s is invalid\n"
 
348
                                     % vars(client))
 
349
                else:
 
350
                    sys.stderr.write(u"Client not found for "
 
351
                                     u"fingerprint: %s\n" % fpr)
488
352
            session.bye()
489
353
            return
490
354
        sent_size = 0
491
355
        while sent_size < len(client.secret):
492
356
            sent = session.send(client.secret[sent_size:])
493
 
            logger.debug(u"Sent: %d, remaining: %d",
494
 
                         sent, len(client.secret)
495
 
                         - (sent_size + sent))
 
357
            if debug:
 
358
                sys.stderr.write(u"Sent: %d, remaining: %d\n"
 
359
                                 % (sent, len(client.secret)
 
360
                                    - (sent_size + sent)))
496
361
            sent_size += sent
497
362
        session.bye()
498
363
 
500
365
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
501
366
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
502
367
    Attributes:
503
 
        settings:       Server settings
 
368
        options:        Command line options
504
369
        clients:        Set() of Client objects
505
370
    """
506
371
    address_family = socket.AF_INET6
507
372
    def __init__(self, *args, **kwargs):
508
 
        if "settings" in kwargs:
509
 
            self.settings = kwargs["settings"]
510
 
            del kwargs["settings"]
 
373
        if "options" in kwargs:
 
374
            self.options = kwargs["options"]
 
375
            del kwargs["options"]
511
376
        if "clients" in kwargs:
512
377
            self.clients = kwargs["clients"]
513
378
            del kwargs["clients"]
516
381
        """This overrides the normal server_bind() function
517
382
        to bind to an interface if one was specified, and also NOT to
518
383
        bind to an address or port if they were not specified."""
519
 
        if self.settings["interface"]:
520
 
            # 25 is from /usr/include/asm-i486/socket.h
521
 
            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
522
388
            try:
523
389
                self.socket.setsockopt(socket.SOL_SOCKET,
524
 
                                       SO_BINDTODEVICE,
525
 
                                       self.settings["interface"])
 
390
                                       socket.SO_BINDTODEVICE,
 
391
                                       self.options.interface)
526
392
            except socket.error, error:
527
393
                if error[0] == errno.EPERM:
528
 
                    logger.error(u"No permission to"
529
 
                                 u" bind to interface %s",
530
 
                                 self.settings["interface"])
 
394
                    sys.stderr.write(u"Warning: No permission to" \
 
395
                                     u" bind to interface %s\n"
 
396
                                     % self.options.interface)
531
397
                else:
532
398
                    raise error
533
399
        # Only bind(2) the socket if we really need to.
536
402
                in6addr_any = "::"
537
403
                self.server_address = (in6addr_any,
538
404
                                       self.server_address[1])
539
 
            elif not self.server_address[1]:
 
405
            elif self.server_address[1] is None:
540
406
                self.server_address = (self.server_address[0],
541
407
                                       0)
542
 
#                 if self.settings["interface"]:
543
 
#                     self.server_address = (self.server_address[0],
544
 
#                                            0, # port
545
 
#                                            0, # flowinfo
546
 
#                                            if_nametoindex
547
 
#                                            (self.settings
548
 
#                                             ["interface"]))
549
408
            return super(type(self), self).server_bind()
550
409
 
551
410
 
583
442
    return delta
584
443
 
585
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
    if debug:
 
457
        sys.stderr.write(u"Adding service '%s' of type '%s' ...\n"
 
458
                         % (serviceName, serviceType))
 
459
    
 
460
    group.AddService(
 
461
            serviceInterface,           # interface
 
462
            avahi.PROTO_INET6,          # protocol
 
463
            dbus.UInt32(0),             # flags
 
464
            serviceName, serviceType,
 
465
            domain, host,
 
466
            dbus.UInt16(servicePort),
 
467
            avahi.string_array_to_txt_array(serviceTXT))
 
468
    group.Commit()
 
469
 
 
470
 
 
471
def remove_service():
 
472
    """From the Avahi server example code"""
 
473
    global group
 
474
    
 
475
    if not group is None:
 
476
        group.Reset()
 
477
 
 
478
 
586
479
def server_state_changed(state):
587
 
    """Derived from the Avahi example code"""
 
480
    """From the Avahi server example code"""
588
481
    if state == avahi.SERVER_COLLISION:
589
 
        logger.error(u"Server name collision")
590
 
        service.remove()
 
482
        sys.stderr.write(u"WARNING: Server name collision\n")
 
483
        remove_service()
591
484
    elif state == avahi.SERVER_RUNNING:
592
 
        service.add()
 
485
        add_service()
593
486
 
594
487
 
595
488
def entry_group_state_changed(state, error):
596
 
    """Derived from the Avahi example code"""
597
 
    logger.debug(u"state change: %i", state)
 
489
    """From the Avahi server example code"""
 
490
    global serviceName, server, rename_count
 
491
    
 
492
    if debug:
 
493
        sys.stderr.write(u"state change: %i\n" % state)
598
494
    
599
495
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
600
 
        logger.debug(u"Service established.")
 
496
        if debug:
 
497
            sys.stderr.write(u"Service established.\n")
601
498
    elif state == avahi.ENTRY_GROUP_COLLISION:
602
 
        logger.warning(u"Service name collision.")
603
 
        service.rename()
 
499
        
 
500
        rename_count = rename_count - 1
 
501
        if rename_count > 0:
 
502
            name = server.GetAlternativeServiceName(name)
 
503
            sys.stderr.write(u"WARNING: Service name collision, "
 
504
                             u"changing name to '%s' ...\n" % name)
 
505
            remove_service()
 
506
            add_service()
 
507
            
 
508
        else:
 
509
            sys.stderr.write(u"ERROR: No suitable service name found "
 
510
                             u"after %i retries, exiting.\n"
 
511
                             % n_rename)
 
512
            main_loop.quit()
604
513
    elif state == avahi.ENTRY_GROUP_FAILURE:
605
 
        logger.critical(u"Error in group state changed %s",
606
 
                        unicode(error))
607
 
        raise AvahiGroupError("State changed: %s", str(error))
 
514
        sys.stderr.write(u"Error in group state changed %s\n"
 
515
                         % unicode(error))
 
516
        main_loop.quit()
 
517
        return
 
518
 
608
519
 
609
520
def if_nametoindex(interface):
610
 
    """Call the C function if_nametoindex(), or equivalent"""
611
 
    global if_nametoindex
 
521
    """Call the C function if_nametoindex()"""
612
522
    try:
613
 
        if "ctypes.util" not in sys.modules:
614
 
            import ctypes.util
615
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
616
 
            (ctypes.util.find_library("c")).if_nametoindex
 
523
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
 
524
        return libc.if_nametoindex(interface)
617
525
    except (OSError, AttributeError):
618
526
        if "struct" not in sys.modules:
619
527
            import struct
620
528
        if "fcntl" not in sys.modules:
621
529
            import fcntl
622
 
        def if_nametoindex(interface):
623
 
            "Get an interface index the hard way, i.e. using fcntl()"
624
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
625
 
            s = socket.socket()
626
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
627
 
                                struct.pack("16s16x", interface))
628
 
            s.close()
629
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
630
 
            return interface_index
631
 
    return if_nametoindex(interface)
632
 
 
633
 
 
634
 
def daemon(nochdir = False, noclose = False):
635
 
    """See daemon(3).  Standard BSD Unix function.
636
 
    This should really exist as os.daemon, but it doesn't (yet)."""
637
 
    if os.fork():
638
 
        sys.exit()
639
 
    os.setsid()
640
 
    if not nochdir:
641
 
        os.chdir("/")
642
 
    if os.fork():
643
 
        sys.exit()
644
 
    if not noclose:
645
 
        # Close all standard open file descriptors
646
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
647
 
        if not stat.S_ISCHR(os.fstat(null).st_mode):
648
 
            raise OSError(errno.ENODEV,
649
 
                          "/dev/null not a character device")
650
 
        os.dup2(null, sys.stdin.fileno())
651
 
        os.dup2(null, sys.stdout.fileno())
652
 
        os.dup2(null, sys.stderr.fileno())
653
 
        if null > 2:
654
 
            os.close(null)
655
 
 
656
 
 
657
 
def main():
658
 
    global main_loop_started
659
 
    main_loop_started = False
660
 
    
661
 
    parser = OptionParser(version = "%%prog %s" % version)
 
530
        SIOCGIFINDEX = 0x8933      # From /usr/include/linux/sockios.h
 
531
        s = socket.socket()
 
532
        ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
 
533
                            struct.pack("16s16x", interface))
 
534
        s.close()
 
535
        interface_index = struct.unpack("I", ifreq[16:20])[0]
 
536
        return interface_index
 
537
 
 
538
 
 
539
if __name__ == '__main__':
 
540
    parser = OptionParser()
662
541
    parser.add_option("-i", "--interface", type="string",
663
 
                      metavar="IF", help="Bind to interface IF")
664
 
    parser.add_option("-a", "--address", type="string",
665
 
                      help="Address to listen for requests on")
666
 
    parser.add_option("-p", "--port", type="int",
 
542
                      default=None, metavar="IF",
 
543
                      help="Bind to interface IF")
 
544
    parser.add_option("--cert", type="string", default="cert.pem",
 
545
                      metavar="FILE",
 
546
                      help="Public key certificate PEM file to use")
 
547
    parser.add_option("--key", type="string", default="key.pem",
 
548
                      metavar="FILE",
 
549
                      help="Private key PEM file to use")
 
550
    parser.add_option("--ca", type="string", default="ca.pem",
 
551
                      metavar="FILE",
 
552
                      help="Certificate Authority certificate PEM file to use")
 
553
    parser.add_option("--crl", type="string", default="crl.pem",
 
554
                      metavar="FILE",
 
555
                      help="Certificate Revokation List PEM file to use")
 
556
    parser.add_option("-p", "--port", type="int", default=None,
667
557
                      help="Port number to receive requests on")
 
558
    parser.add_option("--timeout", type="string", # Parsed later
 
559
                      default="1h",
 
560
                      help="Amount of downtime allowed for clients")
 
561
    parser.add_option("--interval", type="string", # Parsed later
 
562
                      default="5m",
 
563
                      help="How often to check that a client is up")
668
564
    parser.add_option("--check", action="store_true", default=False,
669
565
                      help="Run self-test")
670
 
    parser.add_option("--debug", action="store_true",
671
 
                      help="Debug mode; run in foreground and log to"
672
 
                      " terminal")
673
 
    parser.add_option("--priority", type="string", help="GnuTLS"
674
 
                      " priority string (see GnuTLS documentation)")
675
 
    parser.add_option("--servicename", type="string", metavar="NAME",
676
 
                      help="Zeroconf service name")
677
 
    parser.add_option("--configdir", type="string",
678
 
                      default="/etc/mandos", metavar="DIR",
679
 
                      help="Directory to search for configuration"
680
 
                      " files")
 
566
    parser.add_option("--debug", action="store_true", default=False,
 
567
                      help="Debug mode")
681
568
    (options, args) = parser.parse_args()
682
569
    
683
570
    if options.check:
685
572
        doctest.testmod()
686
573
        sys.exit()
687
574
    
688
 
    # Default values for config file for server-global settings
689
 
    server_defaults = { "interface": "",
690
 
                        "address": "",
691
 
                        "port": "",
692
 
                        "debug": "False",
693
 
                        "priority":
694
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
695
 
                        "servicename": "Mandos",
696
 
                        }
697
 
    
698
 
    # Parse config file for server-global settings
699
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
700
 
    del server_defaults
701
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
702
 
    server_section = "server"
703
 
    # Convert the SafeConfigParser object to a dict
704
 
    server_settings = dict(server_config.items(server_section))
705
 
    # Use getboolean on the boolean config option
706
 
    server_settings["debug"] = server_config.getboolean\
707
 
                               (server_section, "debug")
708
 
    del server_config
709
 
    
710
 
    # Override the settings from the config file with command line
711
 
    # options, if set.
712
 
    for option in ("interface", "address", "port", "debug",
713
 
                   "priority", "servicename", "configdir"):
714
 
        value = getattr(options, option)
715
 
        if value is not None:
716
 
            server_settings[option] = value
717
 
    del options
718
 
    # Now we have our good server settings in "server_settings"
719
 
    
720
 
    debug = server_settings["debug"]
721
 
    
722
 
    if not debug:
723
 
        syslogger.setLevel(logging.WARNING)
724
 
        console.setLevel(logging.WARNING)
725
 
    
726
 
    if server_settings["servicename"] != "Mandos":
727
 
        syslogger.setFormatter(logging.Formatter\
728
 
                               ('Mandos (%s): %%(levelname)s:'
729
 
                                ' %%(message)s'
730
 
                                % server_settings["servicename"]))
731
 
    
732
 
    # Parse config file with clients
733
 
    client_defaults = { "timeout": "1h",
734
 
                        "interval": "5m",
735
 
                        "checker": "fping -q -- %%(host)s",
736
 
                        }
737
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
738
 
    client_config.read(os.path.join(server_settings["configdir"],
739
 
                                    "clients.conf"))
740
 
    
741
 
    global service
742
 
    service = AvahiService(name = server_settings["servicename"],
743
 
                           type = "_mandos._tcp", );
744
 
    if server_settings["interface"]:
745
 
        service.interface = if_nametoindex(server_settings["interface"])
746
 
    
747
 
    global main_loop
748
 
    global bus
749
 
    global server
750
 
    # From the Avahi example code
 
575
    # Parse the time arguments
 
576
    try:
 
577
        options.timeout = string_to_delta(options.timeout)
 
578
    except ValueError:
 
579
        parser.error("option --timeout: Unparseable time")
 
580
    try:
 
581
        options.interval = string_to_delta(options.interval)
 
582
    except ValueError:
 
583
        parser.error("option --interval: Unparseable time")
 
584
    
 
585
    # Parse config file
 
586
    defaults = { "checker": "sleep 1; fping -q -- %%(fqdn)s" }
 
587
    client_config = ConfigParser.SafeConfigParser(defaults)
 
588
    #client_config.readfp(open("secrets.conf"), "secrets.conf")
 
589
    client_config.read("mandos-clients.conf")
 
590
    
 
591
    # From the Avahi server example code
751
592
    DBusGMainLoop(set_as_default=True )
752
593
    main_loop = gobject.MainLoop()
753
594
    bus = dbus.SystemBus()
756
597
            avahi.DBUS_INTERFACE_SERVER )
757
598
    # End of Avahi example code
758
599
    
 
600
    debug = options.debug
 
601
    
759
602
    clients = Set()
760
603
    def remove_from_clients(client):
761
604
        clients.remove(client)
762
605
        if not clients:
763
 
            logger.critical(u"No clients left, exiting")
764
 
            sys.exit()
 
606
            if debug:
 
607
                sys.stderr.write(u"No clients left, exiting\n")
 
608
            main_loop.quit()
765
609
    
766
 
    clients.update(Set(Client(name = section,
 
610
    clients.update(Set(Client(name=section, options=options,
767
611
                              stop_hook = remove_from_clients,
768
 
                              config
769
 
                              = dict(client_config.items(section)))
 
612
                              **(dict(client_config\
 
613
                                      .items(section))))
770
614
                       for section in client_config.sections()))
771
 
    if not clients:
772
 
        logger.critical(u"No clients defined")
773
 
        sys.exit(1)
774
 
    
775
 
    if not debug:
776
 
        logger.removeHandler(console)
777
 
        daemon()
778
 
    
779
 
    pidfilename = "/var/run/mandos/mandos.pid"
780
 
    pid = os.getpid()
781
 
    try:
782
 
        pidfile = open(pidfilename, "w")
783
 
        pidfile.write(str(pid) + "\n")
784
 
        pidfile.close()
785
 
        del pidfile
786
 
    except IOError, err:
787
 
        logger.error(u"Could not write %s file with PID %d",
788
 
                     pidfilename, os.getpid())
789
 
    
790
 
    def cleanup():
791
 
        "Cleanup function; run on exit"
792
 
        global group
793
 
        # From the Avahi example code
794
 
        if not group is None:
795
 
            group.Free()
796
 
            group = None
797
 
        # End of Avahi example code
798
 
        
799
 
        while clients:
800
 
            client = clients.pop()
801
 
            client.stop_hook = None
802
 
            client.stop()
803
 
    
804
 
    atexit.register(cleanup)
805
 
    
806
 
    if not debug:
807
 
        signal.signal(signal.SIGINT, signal.SIG_IGN)
808
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
809
 
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
810
 
    
811
615
    for client in clients:
812
616
        client.start()
813
617
    
814
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
815
 
                                 server_settings["port"]),
 
618
    tcp_server = IPv6_TCPServer((None, options.port),
816
619
                                tcp_handler,
817
 
                                settings=server_settings,
 
620
                                options=options,
818
621
                                clients=clients)
819
 
    # Find out what port we got
820
 
    service.port = tcp_server.socket.getsockname()[1]
821
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
822
 
                u" scope_id %d" % tcp_server.socket.getsockname())
823
 
    
824
 
    #service.interface = tcp_server.socket.getsockname()[3]
825
 
    
 
622
    # Find out what random port we got
 
623
    servicePort = tcp_server.socket.getsockname()[1]
 
624
    if debug:
 
625
        sys.stderr.write(u"Now listening on port %d\n" % servicePort)
 
626
    
 
627
    if options.interface is not None:
 
628
        serviceInterface = if_nametoindex(options.interface)
 
629
    
 
630
    # From the Avahi server example code
 
631
    server.connect_to_signal("StateChanged", server_state_changed)
 
632
    server_state_changed(server.GetState())
 
633
    # End of Avahi example code
 
634
    
 
635
    gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
 
636
                         lambda *args, **kwargs:
 
637
                         tcp_server.handle_request(*args[2:],
 
638
                                                   **kwargs) or True)
826
639
    try:
827
 
        # From the Avahi example code
828
 
        server.connect_to_signal("StateChanged", server_state_changed)
829
 
        try:
830
 
            server_state_changed(server.GetState())
831
 
        except dbus.exceptions.DBusException, error:
832
 
            logger.critical(u"DBusException: %s", error)
833
 
            sys.exit(1)
834
 
        # End of Avahi example code
835
 
        
836
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
837
 
                             lambda *args, **kwargs:
838
 
                             tcp_server.handle_request\
839
 
                             (*args[2:], **kwargs) or True)
840
 
        
841
 
        logger.debug(u"Starting main loop")
842
 
        main_loop_started = True
843
640
        main_loop.run()
844
 
    except AvahiError, error:
845
 
        logger.critical(u"AvahiError: %s" + unicode(error))
846
 
        sys.exit(1)
847
641
    except KeyboardInterrupt:
848
 
        if debug:
849
 
            print
 
642
        print
 
643
    
 
644
    # Cleanup here
850
645
 
851
 
if __name__ == '__main__':
852
 
    main()
 
646
    # From the Avahi server example code
 
647
    if not group is None:
 
648
        group.Free()
 
649
    # End of Avahi example code
 
650
    
 
651
    for client in clients:
 
652
        client.stop_hook = None
 
653
        client.stop()