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  • Committer: Teddy Hogeborn
  • Date: 2008-08-07 21:45:41 UTC
  • Revision ID: teddy@fukt.bsnet.se-20080807214541-pyg8itw6kphz1dy5
* plugbasedclient.c: Renamed to "mandos-client.c".  All users changed.

* plugins.d/mandosclient.c: Renamed to "plugins.d/password-request.c".
                            All users changed.

* plugins.d/passprompt.c: Renamed to "plugins.d/password-prompt.c".
                          All users changed.

* server.conf: Renamed to "mandos.conf".  All users changed.

* server.py: Renamed to "mandos".
  (daemon): Have default values for arguments. Caller changed.

* Makefile (distclean, mostlyclean, maintainer-clean): New aliases for
                                                       "clean".
  (check, run-client, run-server): New.

* network-protocol.txt: New.

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mandos
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
# 
2
31
 
3
32
from __future__ import division
4
33
 
21
50
import signal
22
51
from sets import Set
23
52
import subprocess
 
53
import atexit
 
54
import stat
 
55
import logging
 
56
import logging.handlers
24
57
 
25
58
import dbus
26
59
import gobject
28
61
from dbus.mainloop.glib import DBusGMainLoop
29
62
import ctypes
30
63
 
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
 
64
 
 
65
logger = logging.Logger('mandos')
 
66
syslogger = logging.handlers.SysLogHandler\
 
67
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON)
 
68
syslogger.setFormatter(logging.Formatter\
 
69
                        ('%(levelname)s: %(message)s'))
 
70
logger.addHandler(syslogger)
 
71
del syslogger
 
72
 
 
73
 
 
74
class AvahiError(Exception):
 
75
    def __init__(self, value):
 
76
        self.value = value
 
77
    def __str__(self):
 
78
        return repr(self.value)
 
79
 
 
80
class AvahiServiceError(AvahiError):
 
81
    pass
 
82
 
 
83
class AvahiGroupError(AvahiError):
 
84
    pass
 
85
 
 
86
 
 
87
class AvahiService(object):
 
88
    """An Avahi (Zeroconf) service.
 
89
    Attributes:
 
90
    interface: integer; avahi.IF_UNSPEC or an interface index.
 
91
               Used to optionally bind to the specified interface.
 
92
    name: string; Example: 'Mandos'
 
93
    type: string; Example: '_mandos._tcp'.
 
94
                  See <http://www.dns-sd.org/ServiceTypes.html>
 
95
    port: integer; what port to announce
 
96
    TXT: list of strings; TXT record for the service
 
97
    domain: string; Domain to publish on, default to .local if empty.
 
98
    host: string; Host to publish records for, default is localhost
 
99
    max_renames: integer; maximum number of renames
 
100
    rename_count: integer; counter so we only rename after collisions
 
101
                  a sensible number of times
 
102
    """
 
103
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
 
104
                 type = None, port = None, TXT = None, domain = "",
 
105
                 host = "", max_renames = 12):
 
106
        self.interface = interface
 
107
        self.name = name
 
108
        self.type = type
 
109
        self.port = port
 
110
        if TXT is None:
 
111
            self.TXT = []
 
112
        else:
 
113
            self.TXT = TXT
 
114
        self.domain = domain
 
115
        self.host = host
 
116
        self.rename_count = 0
 
117
    def rename(self):
 
118
        """Derived from the Avahi example code"""
 
119
        if self.rename_count >= self.max_renames:
 
120
            logger.critical(u"No suitable service name found after %i"
 
121
                            u" retries, exiting.", rename_count)
 
122
            raise AvahiServiceError("Too many renames")
 
123
        name = server.GetAlternativeServiceName(name)
 
124
        logger.error(u"Changing name to %r ...", name)
 
125
        self.remove()
 
126
        self.add()
 
127
        self.rename_count += 1
 
128
    def remove(self):
 
129
        """Derived from the Avahi example code"""
 
130
        if group is not None:
 
131
            group.Reset()
 
132
    def add(self):
 
133
        """Derived from the Avahi example code"""
 
134
        global group
 
135
        if group is None:
 
136
            group = dbus.Interface\
 
137
                    (bus.get_object(avahi.DBUS_NAME,
 
138
                                    server.EntryGroupNew()),
 
139
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
 
140
            group.connect_to_signal('StateChanged',
 
141
                                    entry_group_state_changed)
 
142
        logger.debug(u"Adding service '%s' of type '%s' ...",
 
143
                     service.name, service.type)
 
144
        group.AddService(
 
145
                self.interface,         # interface
 
146
                avahi.PROTO_INET6,      # protocol
 
147
                dbus.UInt32(0),         # flags
 
148
                self.name, self.type,
 
149
                self.domain, self.host,
 
150
                dbus.UInt16(self.port),
 
151
                avahi.string_array_to_txt_array(self.TXT))
 
152
        group.Commit()
 
153
 
 
154
# From the Avahi example code:
 
155
group = None                            # our entry group
45
156
# End of Avahi example code
46
157
 
47
158
 
53
164
                 uniquely identify the client
54
165
    secret:    bytestring; sent verbatim (over TLS) to client
55
166
    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
 
167
    created:   datetime.datetime(); object creation, not client host
 
168
    last_checked_ok: datetime.datetime() or None if not yet checked OK
 
169
    timeout:   datetime.timedelta(); How long from last_checked_ok
 
170
                                     until this client is invalid
60
171
    interval:  datetime.timedelta(); How often to start a new checker
61
172
    stop_hook: If set, called by stop() as stop_hook(self)
62
173
    checker:   subprocess.Popen(); a running checker process used
63
174
                                   to see if the client lives.
64
 
                                   Is None if no process is running.
 
175
                                   'None' if no process is running.
65
176
    checker_initiator_tag: a gobject event source tag, or None
66
177
    stop_initiator_tag:    - '' -
67
178
    checker_callback_tag:  - '' -
68
179
    checker_command: string; External command which is run to check if
69
 
                     client lives.  %()s expansions are done at
 
180
                     client lives.  %() expansions are done at
70
181
                     runtime with vars(self) as dict, so that for
71
182
                     instance %(name)s can be used in the command.
72
183
    Private attibutes:
73
184
    _timeout: Real variable for 'timeout'
74
185
    _interval: Real variable for 'interval'
75
 
    _timeout_milliseconds: Used by gobject.timeout_add()
 
186
    _timeout_milliseconds: Used when calling gobject.timeout_add()
76
187
    _interval_milliseconds: - '' -
77
188
    """
78
189
    def _set_timeout(self, timeout):
98
209
    interval = property(lambda self: self._interval,
99
210
                        _set_interval)
100
211
    del _set_interval
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):
 
212
    def __init__(self, name = None, stop_hook=None, config={}):
 
213
        """Note: the 'checker' key in 'config' sets the
 
214
        'checker_command' attribute and *not* the 'checker'
 
215
        attribute."""
104
216
        self.name = name
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)
 
217
        logger.debug(u"Creating client %r", self.name)
 
218
        # Uppercase and remove spaces from fingerprint for later
 
219
        # comparison purposes with return value from the fingerprint()
 
220
        # function
 
221
        self.fingerprint = config["fingerprint"].upper()\
 
222
                           .replace(u" ", u"")
 
223
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
 
224
        if "secret" in config:
 
225
            self.secret = config["secret"].decode(u"base64")
 
226
        elif "secfile" in config:
 
227
            sf = open(config["secfile"])
113
228
            self.secret = sf.read()
114
229
            sf.close()
115
230
        else:
116
 
            raise RuntimeError(u"No secret or secfile for client %s"
117
 
                               % self.name)
118
 
        self.fqdn = fqdn                # string
 
231
            raise TypeError(u"No secret or secfile for client %s"
 
232
                            % self.name)
 
233
        self.fqdn = config.get("fqdn", "")
119
234
        self.created = datetime.datetime.now()
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
 
235
        self.last_checked_ok = None
 
236
        self.timeout = string_to_delta(config["timeout"])
 
237
        self.interval = string_to_delta(config["interval"])
129
238
        self.stop_hook = stop_hook
130
239
        self.checker = None
131
240
        self.checker_initiator_tag = None
132
241
        self.stop_initiator_tag = None
133
242
        self.checker_callback_tag = None
134
 
        self.check_command = checker
 
243
        self.check_command = config["checker"]
135
244
    def start(self):
136
 
        """Start this clients checker and timeout hooks"""
 
245
        """Start this client's checker and timeout hooks"""
137
246
        # Schedule a new checker to be started an 'interval' from now,
138
247
        # and every interval from then on.
139
248
        self.checker_initiator_tag = gobject.timeout_add\
147
256
                                   self.stop)
148
257
    def stop(self):
149
258
        """Stop this client.
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:
 
259
        The possibility that a client might be restarted is left open,
 
260
        but not currently used."""
 
261
        # If this client doesn't have a secret, it is already stopped.
 
262
        if self.secret:
 
263
            logger.info(u"Stopping client %s", self.name)
 
264
            self.secret = None
 
265
        else:
 
266
            return False
 
267
        if getattr(self, "stop_initiator_tag", False):
156
268
            gobject.source_remove(self.stop_initiator_tag)
157
269
            self.stop_initiator_tag = None
158
 
        if self.checker_initiator_tag:
 
270
        if getattr(self, "checker_initiator_tag", False):
159
271
            gobject.source_remove(self.checker_initiator_tag)
160
272
            self.checker_initiator_tag = None
161
273
        self.stop_checker()
164
276
        # Do not run this again if called by a gobject.timeout_add
165
277
        return False
166
278
    def __del__(self):
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()
 
279
        self.stop_hook = None
 
280
        self.stop()
177
281
    def checker_callback(self, pid, condition):
178
282
        """The checker has completed, so take appropriate actions."""
179
283
        now = datetime.datetime.now()
 
284
        self.checker_callback_tag = None
 
285
        self.checker = None
180
286
        if os.WIFEXITED(condition) \
181
287
               and (os.WEXITSTATUS(condition) == 0):
182
 
            if debug:
183
 
                sys.stderr.write(u"Checker for %(name)s succeeded\n"
184
 
                                 % vars(self))
185
 
            self.last_seen = now
 
288
            logger.info(u"Checker for %(name)s succeeded",
 
289
                        vars(self))
 
290
            self.last_checked_ok = now
186
291
            gobject.source_remove(self.stop_initiator_tag)
187
292
            self.stop_initiator_tag = gobject.timeout_add\
188
293
                                      (self._timeout_milliseconds,
189
294
                                       self.stop)
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
 
295
        elif not os.WIFEXITED(condition):
 
296
            logger.warning(u"Checker for %(name)s crashed?",
 
297
                           vars(self))
 
298
        else:
 
299
            logger.info(u"Checker for %(name)s failed",
 
300
                        vars(self))
199
301
    def start_checker(self):
200
302
        """Start a new checker subprocess if one is not running.
201
303
        If a checker already exists, leave it running and do
202
304
        nothing."""
 
305
        # The reason for not killing a running checker is that if we
 
306
        # did that, then if a checker (for some reason) started
 
307
        # running slowly and taking more than 'interval' time, the
 
308
        # client would inevitably timeout, since no checker would get
 
309
        # a chance to run to completion.  If we instead leave running
 
310
        # checkers alone, the checker would have to take more time
 
311
        # than 'timeout' for the client to be declared invalid, which
 
312
        # is as it should be.
203
313
        if self.checker is None:
204
 
            if debug:
205
 
                sys.stderr.write(u"Starting checker for %s\n"
206
 
                                 % self.name)
207
314
            try:
 
315
                # In case check_command has exactly one % operator
208
316
                command = self.check_command % self.fqdn
209
317
            except TypeError:
 
318
                # Escape attributes for the shell
210
319
                escaped_attrs = dict((key, re.escape(str(val)))
211
320
                                     for key, val in
212
321
                                     vars(self).iteritems())
213
 
                command = self.check_command % escaped_attrs
 
322
                try:
 
323
                    command = self.check_command % escaped_attrs
 
324
                except TypeError, error:
 
325
                    logger.error(u'Could not format string "%s":'
 
326
                                 u' %s', self.check_command, error)
 
327
                    return True # Try again later
214
328
            try:
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)
 
329
                logger.info(u"Starting checker %r for %s",
 
330
                            command, self.name)
 
331
                self.checker = subprocess.Popen(command,
 
332
                                                close_fds=True,
 
333
                                                shell=True, cwd="/")
 
334
                self.checker_callback_tag = gobject.child_watch_add\
 
335
                                            (self.checker.pid,
 
336
                                             self.checker_callback)
224
337
            except subprocess.OSError, error:
225
 
                sys.stderr.write(u"Failed to start subprocess: %s\n"
226
 
                                 % error)
 
338
                logger.error(u"Failed to start subprocess: %s",
 
339
                             error)
227
340
        # Re-run this periodically if run by gobject.timeout_add
228
341
        return True
229
342
    def stop_checker(self):
230
343
        """Force the checker process, if any, to stop."""
231
 
        if not hasattr(self, "checker") or self.checker is None:
 
344
        if self.checker_callback_tag:
 
345
            gobject.source_remove(self.checker_callback_tag)
 
346
            self.checker_callback_tag = None
 
347
        if getattr(self, "checker", None) is None:
232
348
            return
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)
 
349
        logger.debug("Stopping checker for %(name)s", vars(self))
 
350
        try:
 
351
            os.kill(self.checker.pid, signal.SIGTERM)
 
352
            #os.sleep(0.5)
 
353
            #if self.checker.poll() is None:
 
354
            #    os.kill(self.checker.pid, signal.SIGKILL)
 
355
        except OSError, error:
 
356
            if error.errno != errno.ESRCH: # No such process
 
357
                raise
238
358
        self.checker = None
239
 
    def still_valid(self, now=None):
 
359
    def still_valid(self):
240
360
        """Has the timeout not yet passed for this client?"""
241
 
        if now is None:
242
 
            now = datetime.datetime.now()
243
 
        if self.last_seen is None:
 
361
        now = datetime.datetime.now()
 
362
        if self.last_checked_ok is None:
244
363
            return now < (self.created + self.timeout)
245
364
        else:
246
 
            return now < (self.last_seen + self.timeout)
 
365
            return now < (self.last_checked_ok + self.timeout)
247
366
 
248
367
 
249
368
def peer_certificate(session):
 
369
    "Return the peer's OpenPGP certificate as a bytestring"
250
370
    # If not an OpenPGP certificate...
251
371
    if gnutls.library.functions.gnutls_certificate_type_get\
252
372
            (session._c_object) \
263
383
 
264
384
 
265
385
def fingerprint(openpgp):
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))
 
386
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
270
387
    # New GnuTLS "datum" with the OpenPGP public key
271
388
    datum = gnutls.library.types.gnutls_datum_t\
272
389
        (ctypes.cast(ctypes.c_char_p(openpgp),
273
390
                     ctypes.POINTER(ctypes.c_ubyte)),
274
391
         ctypes.c_uint(len(openpgp)))
 
392
    # New empty GnuTLS certificate
 
393
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
394
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
395
        (ctypes.byref(crt))
275
396
    # Import the OpenPGP public key into the certificate
276
 
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
277
 
        (crt,
278
 
         ctypes.byref(datum),
279
 
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
 
397
    gnutls.library.functions.gnutls_openpgp_crt_import\
 
398
                    (crt, ctypes.byref(datum),
 
399
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
280
400
    # New buffer for the fingerprint
281
401
    buffer = ctypes.create_string_buffer(20)
282
402
    buffer_length = ctypes.c_size_t()
298
418
    Note: This will run in its own forked process."""
299
419
    
300
420
    def handle(self):
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())
 
421
        logger.info(u"TCP connection from: %s",
 
422
                     unicode(self.client_address))
 
423
        session = gnutls.connection.ClientSession\
 
424
                  (self.request, gnutls.connection.X509Credentials())
 
425
        
 
426
        line = self.request.makefile().readline()
 
427
        logger.debug(u"Protocol version: %r", line)
 
428
        try:
 
429
            if int(line.strip().split()[0]) > 1:
 
430
                raise RuntimeError
 
431
        except (ValueError, IndexError, RuntimeError), error:
 
432
            logger.error(u"Unknown protocol version: %s", error)
 
433
            return
 
434
        
 
435
        # Note: gnutls.connection.X509Credentials is really a generic
 
436
        # GnuTLS certificate credentials object so long as no X.509
 
437
        # keys are added to it.  Therefore, we can use it here despite
 
438
        # using OpenPGP certificates.
310
439
        
311
440
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
312
441
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
313
442
        #                "+DHE-DSS"))
314
 
        priority = "SECURE256"
315
 
        
 
443
        priority = "NORMAL"             # Fallback default, since this
 
444
                                        # MUST be set.
 
445
        if self.server.settings["priority"]:
 
446
            priority = self.server.settings["priority"]
316
447
        gnutls.library.functions.gnutls_priority_set_direct\
317
448
            (session._c_object, priority, None);
318
449
        
319
450
        try:
320
451
            session.handshake()
321
452
        except gnutls.errors.GNUTLSError, error:
322
 
            if debug:
323
 
                sys.stderr.write(u"Handshake failed: %s\n" % error)
 
453
            logger.warning(u"Handshake failed: %s", error)
324
454
            # Do not run session.bye() here: the session is not
325
455
            # established.  Just abandon the request.
326
456
            return
327
457
        try:
328
458
            fpr = fingerprint(peer_certificate(session))
329
459
        except (TypeError, gnutls.errors.GNUTLSError), error:
330
 
            if debug:
331
 
                sys.stderr.write(u"Bad certificate: %s\n" % error)
 
460
            logger.warning(u"Bad certificate: %s", error)
332
461
            session.bye()
333
462
            return
334
 
        if debug:
335
 
            sys.stderr.write(u"Fingerprint: %s\n" % fpr)
 
463
        logger.debug(u"Fingerprint: %s", fpr)
336
464
        client = None
337
 
        for c in clients:
 
465
        for c in self.server.clients:
338
466
            if c.fingerprint == fpr:
339
467
                client = c
340
468
                break
 
469
        if not client:
 
470
            logger.warning(u"Client not found for fingerprint: %s",
 
471
                           fpr)
 
472
            session.bye()
 
473
            return
341
474
        # Have to check if client.still_valid(), since it is possible
342
475
        # that the client timed out while establishing the GnuTLS
343
476
        # session.
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)
 
477
        if not client.still_valid():
 
478
            logger.warning(u"Client %(name)s is invalid",
 
479
                           vars(client))
352
480
            session.bye()
353
481
            return
354
482
        sent_size = 0
355
483
        while sent_size < len(client.secret):
356
484
            sent = session.send(client.secret[sent_size:])
357
 
            if debug:
358
 
                sys.stderr.write(u"Sent: %d, remaining: %d\n"
359
 
                                 % (sent, len(client.secret)
360
 
                                    - (sent_size + sent)))
 
485
            logger.debug(u"Sent: %d, remaining: %d",
 
486
                         sent, len(client.secret)
 
487
                         - (sent_size + sent))
361
488
            sent_size += sent
362
489
        session.bye()
363
490
 
365
492
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
366
493
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
367
494
    Attributes:
368
 
        options:        Command line options
 
495
        settings:       Server settings
369
496
        clients:        Set() of Client objects
370
497
    """
371
498
    address_family = socket.AF_INET6
372
499
    def __init__(self, *args, **kwargs):
373
 
        if "options" in kwargs:
374
 
            self.options = kwargs["options"]
375
 
            del kwargs["options"]
 
500
        if "settings" in kwargs:
 
501
            self.settings = kwargs["settings"]
 
502
            del kwargs["settings"]
376
503
        if "clients" in kwargs:
377
504
            self.clients = kwargs["clients"]
378
505
            del kwargs["clients"]
381
508
        """This overrides the normal server_bind() function
382
509
        to bind to an interface if one was specified, and also NOT to
383
510
        bind to an address or port if they were not specified."""
384
 
        if self.options.interface:
385
 
            if not hasattr(socket, "SO_BINDTODEVICE"):
386
 
                # From /usr/include/asm-i486/socket.h
387
 
                socket.SO_BINDTODEVICE = 25
 
511
        if self.settings["interface"]:
 
512
            # 25 is from /usr/include/asm-i486/socket.h
 
513
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
388
514
            try:
389
515
                self.socket.setsockopt(socket.SOL_SOCKET,
390
 
                                       socket.SO_BINDTODEVICE,
391
 
                                       self.options.interface)
 
516
                                       SO_BINDTODEVICE,
 
517
                                       self.settings["interface"])
392
518
            except socket.error, error:
393
519
                if error[0] == errno.EPERM:
394
 
                    sys.stderr.write(u"Warning: No permission to" \
395
 
                                     u" bind to interface %s\n"
396
 
                                     % self.options.interface)
 
520
                    logger.error(u"No permission to"
 
521
                                 u" bind to interface %s",
 
522
                                 self.settings["interface"])
397
523
                else:
398
524
                    raise error
399
525
        # Only bind(2) the socket if we really need to.
442
568
    return delta
443
569
 
444
570
 
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
 
 
479
571
def server_state_changed(state):
480
 
    """From the Avahi server example code"""
 
572
    """Derived from the Avahi example code"""
481
573
    if state == avahi.SERVER_COLLISION:
482
 
        sys.stderr.write(u"WARNING: Server name collision\n")
483
 
        remove_service()
 
574
        logger.error(u"Server name collision")
 
575
        service.remove()
484
576
    elif state == avahi.SERVER_RUNNING:
485
 
        add_service()
 
577
        service.add()
486
578
 
487
579
 
488
580
def entry_group_state_changed(state, error):
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)
 
581
    """Derived from the Avahi example code"""
 
582
    logger.debug(u"state change: %i", state)
494
583
    
495
584
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
496
 
        if debug:
497
 
            sys.stderr.write(u"Service established.\n")
 
585
        logger.debug(u"Service established.")
498
586
    elif state == avahi.ENTRY_GROUP_COLLISION:
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()
 
587
        logger.warning(u"Service name collision.")
 
588
        service.rename()
513
589
    elif state == avahi.ENTRY_GROUP_FAILURE:
514
 
        sys.stderr.write(u"Error in group state changed %s\n"
515
 
                         % unicode(error))
516
 
        main_loop.quit()
517
 
        return
518
 
 
 
590
        logger.critical(u"Error in group state changed %s",
 
591
                        unicode(error))
 
592
        raise AvahiGroupError("State changed: %s", str(error))
519
593
 
520
594
def if_nametoindex(interface):
521
 
    """Call the C function if_nametoindex()"""
 
595
    """Call the C function if_nametoindex(), or equivalent"""
 
596
    global if_nametoindex
522
597
    try:
523
 
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
524
 
        return libc.if_nametoindex(interface)
 
598
        if "ctypes.util" not in sys.modules:
 
599
            import ctypes.util
 
600
        if_nametoindex = ctypes.cdll.LoadLibrary\
 
601
            (ctypes.util.find_library("c")).if_nametoindex
525
602
    except (OSError, AttributeError):
526
603
        if "struct" not in sys.modules:
527
604
            import struct
528
605
        if "fcntl" not in sys.modules:
529
606
            import fcntl
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__':
 
607
        def if_nametoindex(interface):
 
608
            "Get an interface index the hard way, i.e. using fcntl()"
 
609
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
 
610
            s = socket.socket()
 
611
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
 
612
                                struct.pack("16s16x", interface))
 
613
            s.close()
 
614
            interface_index = struct.unpack("I", ifreq[16:20])[0]
 
615
            return interface_index
 
616
    return if_nametoindex(interface)
 
617
 
 
618
 
 
619
def daemon(nochdir = False, noclose = False):
 
620
    """See daemon(3).  Standard BSD Unix function.
 
621
    This should really exist as os.daemon, but it doesn't (yet)."""
 
622
    if os.fork():
 
623
        sys.exit()
 
624
    os.setsid()
 
625
    if not nochdir:
 
626
        os.chdir("/")
 
627
    if os.fork():
 
628
        sys.exit()
 
629
    if not noclose:
 
630
        # Close all standard open file descriptors
 
631
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
 
632
        if not stat.S_ISCHR(os.fstat(null).st_mode):
 
633
            raise OSError(errno.ENODEV,
 
634
                          "/dev/null not a character device")
 
635
        os.dup2(null, sys.stdin.fileno())
 
636
        os.dup2(null, sys.stdout.fileno())
 
637
        os.dup2(null, sys.stderr.fileno())
 
638
        if null > 2:
 
639
            os.close(null)
 
640
 
 
641
 
 
642
def main():
 
643
    global main_loop_started
 
644
    main_loop_started = False
 
645
    
540
646
    parser = OptionParser()
541
647
    parser.add_option("-i", "--interface", type="string",
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,
 
648
                      metavar="IF", help="Bind to interface IF")
 
649
    parser.add_option("-a", "--address", type="string",
 
650
                      help="Address to listen for requests on")
 
651
    parser.add_option("-p", "--port", type="int",
557
652
                      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")
564
653
    parser.add_option("--check", action="store_true", default=False,
565
654
                      help="Run self-test")
566
655
    parser.add_option("--debug", action="store_true", default=False,
567
 
                      help="Debug mode")
 
656
                      help="Debug mode; run in foreground and log to"
 
657
                      " terminal")
 
658
    parser.add_option("--priority", type="string", help="GnuTLS"
 
659
                      " priority string (see GnuTLS documentation)")
 
660
    parser.add_option("--servicename", type="string", metavar="NAME",
 
661
                      help="Zeroconf service name")
 
662
    parser.add_option("--configdir", type="string",
 
663
                      default="/etc/mandos", metavar="DIR",
 
664
                      help="Directory to search for configuration"
 
665
                      " files")
568
666
    (options, args) = parser.parse_args()
569
667
    
570
668
    if options.check:
572
670
        doctest.testmod()
573
671
        sys.exit()
574
672
    
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
 
673
    # Default values for config file for server-global settings
 
674
    server_defaults = { "interface": "",
 
675
                        "address": "",
 
676
                        "port": "",
 
677
                        "debug": "False",
 
678
                        "priority":
 
679
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
 
680
                        "servicename": "Mandos",
 
681
                        }
 
682
    
 
683
    # Parse config file for server-global settings
 
684
    server_config = ConfigParser.SafeConfigParser(server_defaults)
 
685
    del server_defaults
 
686
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
 
687
    server_section = "server"
 
688
    # Convert the SafeConfigParser object to a dict
 
689
    server_settings = dict(server_config.items(server_section))
 
690
    # Use getboolean on the boolean config option
 
691
    server_settings["debug"] = server_config.getboolean\
 
692
                               (server_section, "debug")
 
693
    del server_config
 
694
    
 
695
    # Override the settings from the config file with command line
 
696
    # options, if set.
 
697
    for option in ("interface", "address", "port", "debug",
 
698
                   "priority", "servicename", "configdir"):
 
699
        value = getattr(options, option)
 
700
        if value is not None:
 
701
            server_settings[option] = value
 
702
    del options
 
703
    # Now we have our good server settings in "server_settings"
 
704
    
 
705
    # Parse config file with clients
 
706
    client_defaults = { "timeout": "1h",
 
707
                        "interval": "5m",
 
708
                        "checker": "fping -q -- %%(fqdn)s",
 
709
                        }
 
710
    client_config = ConfigParser.SafeConfigParser(client_defaults)
 
711
    client_config.read(os.path.join(server_settings["configdir"],
 
712
                                    "clients.conf"))
 
713
    
 
714
    global service
 
715
    service = AvahiService(name = server_settings["servicename"],
 
716
                           type = "_mandos._tcp", );
 
717
    if server_settings["interface"]:
 
718
        service.interface = if_nametoindex(server_settings["interface"])
 
719
    
 
720
    global main_loop
 
721
    global bus
 
722
    global server
 
723
    # From the Avahi example code
592
724
    DBusGMainLoop(set_as_default=True )
593
725
    main_loop = gobject.MainLoop()
594
726
    bus = dbus.SystemBus()
597
729
            avahi.DBUS_INTERFACE_SERVER )
598
730
    # End of Avahi example code
599
731
    
600
 
    debug = options.debug
 
732
    debug = server_settings["debug"]
 
733
    
 
734
    if debug:
 
735
        console = logging.StreamHandler()
 
736
        # console.setLevel(logging.DEBUG)
 
737
        console.setFormatter(logging.Formatter\
 
738
                             ('%(levelname)s: %(message)s'))
 
739
        logger.addHandler(console)
 
740
        del console
601
741
    
602
742
    clients = Set()
603
743
    def remove_from_clients(client):
604
744
        clients.remove(client)
605
745
        if not clients:
606
 
            if debug:
607
 
                sys.stderr.write(u"No clients left, exiting\n")
608
 
            main_loop.quit()
 
746
            logger.critical(u"No clients left, exiting")
 
747
            sys.exit()
609
748
    
610
 
    clients.update(Set(Client(name=section, options=options,
 
749
    clients.update(Set(Client(name = section,
611
750
                              stop_hook = remove_from_clients,
612
 
                              **(dict(client_config\
613
 
                                      .items(section))))
 
751
                              config
 
752
                              = dict(client_config.items(section)))
614
753
                       for section in client_config.sections()))
 
754
    
 
755
    if not debug:
 
756
        daemon()
 
757
    
 
758
    def cleanup():
 
759
        "Cleanup function; run on exit"
 
760
        global group
 
761
        # From the Avahi example code
 
762
        if not group is None:
 
763
            group.Free()
 
764
            group = None
 
765
        # End of Avahi example code
 
766
        
 
767
        while clients:
 
768
            client = clients.pop()
 
769
            client.stop_hook = None
 
770
            client.stop()
 
771
    
 
772
    atexit.register(cleanup)
 
773
    
 
774
    if not debug:
 
775
        signal.signal(signal.SIGINT, signal.SIG_IGN)
 
776
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
 
777
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
 
778
    
615
779
    for client in clients:
616
780
        client.start()
617
781
    
618
 
    tcp_server = IPv6_TCPServer((None, options.port),
 
782
    tcp_server = IPv6_TCPServer((server_settings["address"],
 
783
                                 server_settings["port"]),
619
784
                                tcp_handler,
620
 
                                options=options,
 
785
                                settings=server_settings,
621
786
                                clients=clients)
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)
 
787
    # Find out what port we got
 
788
    service.port = tcp_server.socket.getsockname()[1]
 
789
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
 
790
                u" scope_id %d" % tcp_server.socket.getsockname())
 
791
    
 
792
    #service.interface = tcp_server.socket.getsockname()[3]
 
793
    
639
794
    try:
 
795
        # From the Avahi example code
 
796
        server.connect_to_signal("StateChanged", server_state_changed)
 
797
        try:
 
798
            server_state_changed(server.GetState())
 
799
        except dbus.exceptions.DBusException, error:
 
800
            logger.critical(u"DBusException: %s", error)
 
801
            sys.exit(1)
 
802
        # End of Avahi example code
 
803
        
 
804
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
 
805
                             lambda *args, **kwargs:
 
806
                             tcp_server.handle_request\
 
807
                             (*args[2:], **kwargs) or True)
 
808
        
 
809
        logger.debug("Starting main loop")
 
810
        main_loop_started = True
640
811
        main_loop.run()
 
812
    except AvahiError, error:
 
813
        logger.critical(u"AvahiError: %s" + unicode(error))
 
814
        sys.exit(1)
641
815
    except KeyboardInterrupt:
642
 
        print
643
 
    
644
 
    # Cleanup here
 
816
        if debug:
 
817
            print
645
818
 
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()
 
819
if __name__ == '__main__':
 
820
    main()