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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
 
import logging
32
 
import logging.handlers
33
 
 
34
 
# logghandler.setFormatter(logging.Formatter('%(levelname)s %(message)s')
35
64
 
36
65
logger = logging.Logger('mandos')
37
 
logger.addHandler(logging.handlers.SysLogHandler(facility = logging.handlers.SysLogHandler.LOG_DAEMON))
38
 
 
39
 
# This variable is used to optionally bind to a specified interface.
40
 
# It is a global variable to fit in with the other variables from the
41
 
# Avahi server example code.
42
 
serviceInterface = avahi.IF_UNSPEC
43
 
# From the Avahi server example code:
44
 
serviceName = "Mandos"
45
 
serviceType = "_mandos._tcp" # http://www.dns-sd.org/ServiceTypes.html
46
 
servicePort = None                      # Not known at startup
47
 
serviceTXT = []                         # TXT record for the service
48
 
domain = ""                  # Domain to publish on, default to .local
49
 
host = ""          # Host to publish records for, default to localhost
50
 
group = None #our entry group
51
 
rename_count = 12       # Counter so we only rename after collisions a
52
 
                        # sensible number of times
 
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
53
156
# End of Avahi example code
54
157
 
55
158
 
61
164
                 uniquely identify the client
62
165
    secret:    bytestring; sent verbatim (over TLS) to client
63
166
    fqdn:      string (FQDN); available for use by the checker command
64
 
    created:   datetime.datetime()
65
 
    last_seen: datetime.datetime() or None if not yet seen
66
 
    timeout:   datetime.timedelta(); How long from last_seen until
67
 
                                     this client is invalid
 
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
68
171
    interval:  datetime.timedelta(); How often to start a new checker
69
172
    stop_hook: If set, called by stop() as stop_hook(self)
70
173
    checker:   subprocess.Popen(); a running checker process used
71
174
                                   to see if the client lives.
72
 
                                   Is None if no process is running.
 
175
                                   'None' if no process is running.
73
176
    checker_initiator_tag: a gobject event source tag, or None
74
177
    stop_initiator_tag:    - '' -
75
178
    checker_callback_tag:  - '' -
76
179
    checker_command: string; External command which is run to check if
77
 
                     client lives.  %()s expansions are done at
 
180
                     client lives.  %() expansions are done at
78
181
                     runtime with vars(self) as dict, so that for
79
182
                     instance %(name)s can be used in the command.
80
183
    Private attibutes:
81
184
    _timeout: Real variable for 'timeout'
82
185
    _interval: Real variable for 'interval'
83
 
    _timeout_milliseconds: Used by gobject.timeout_add()
 
186
    _timeout_milliseconds: Used when calling gobject.timeout_add()
84
187
    _interval_milliseconds: - '' -
85
188
    """
86
189
    def _set_timeout(self, timeout):
106
209
    interval = property(lambda self: self._interval,
107
210
                        _set_interval)
108
211
    del _set_interval
109
 
    def __init__(self, name=None, options=None, stop_hook=None,
110
 
                 fingerprint=None, secret=None, secfile=None, fqdn=None,
111
 
                 timeout=None, interval=-1, checker=None):
 
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."""
112
216
        self.name = name
113
 
        # Uppercase and remove spaces from fingerprint
114
 
        # for later comparison purposes with return value of
115
 
        # the fingerprint() function
116
 
        self.fingerprint = fingerprint.upper().replace(u" ", u"")
117
 
        if secret:
118
 
            self.secret = secret.decode(u"base64")
119
 
        elif secfile:
120
 
            sf = open(secfile)
 
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"])
121
228
            self.secret = sf.read()
122
229
            sf.close()
123
230
        else:
124
 
            raise RuntimeError(u"No secret or secfile for client %s"
125
 
                               % self.name)
126
 
        self.fqdn = fqdn                # string
 
231
            raise TypeError(u"No secret or secfile for client %s"
 
232
                            % self.name)
 
233
        self.fqdn = config.get("fqdn", "")
127
234
        self.created = datetime.datetime.now()
128
 
        self.last_seen = None
129
 
        if timeout is None:
130
 
            timeout = options.timeout
131
 
        self.timeout = timeout
132
 
        if interval == -1:
133
 
            interval = options.interval
134
 
        else:
135
 
            interval = string_to_delta(interval)
136
 
        self.interval = interval
 
235
        self.last_checked_ok = None
 
236
        self.timeout = string_to_delta(config["timeout"])
 
237
        self.interval = string_to_delta(config["interval"])
137
238
        self.stop_hook = stop_hook
138
239
        self.checker = None
139
240
        self.checker_initiator_tag = None
140
241
        self.stop_initiator_tag = None
141
242
        self.checker_callback_tag = None
142
 
        self.check_command = checker
 
243
        self.check_command = config["checker"]
143
244
    def start(self):
144
 
        """Start this clients checker and timeout hooks"""
 
245
        """Start this client's checker and timeout hooks"""
145
246
        # Schedule a new checker to be started an 'interval' from now,
146
247
        # and every interval from then on.
147
248
        self.checker_initiator_tag = gobject.timeout_add\
155
256
                                   self.stop)
156
257
    def stop(self):
157
258
        """Stop this client.
158
 
        The possibility that this client might be restarted is left
159
 
        open, but not currently used."""
160
 
        logger.debug(u"Stopping client %s", self.name)
161
 
        self.secret = None
162
 
        if self.stop_initiator_tag:
 
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):
163
268
            gobject.source_remove(self.stop_initiator_tag)
164
269
            self.stop_initiator_tag = None
165
 
        if self.checker_initiator_tag:
 
270
        if getattr(self, "checker_initiator_tag", False):
166
271
            gobject.source_remove(self.checker_initiator_tag)
167
272
            self.checker_initiator_tag = None
168
273
        self.stop_checker()
171
276
        # Do not run this again if called by a gobject.timeout_add
172
277
        return False
173
278
    def __del__(self):
174
 
        # Some code duplication here and in stop()
175
 
        if hasattr(self, "stop_initiator_tag") \
176
 
               and self.stop_initiator_tag:
177
 
            gobject.source_remove(self.stop_initiator_tag)
178
 
            self.stop_initiator_tag = None
179
 
        if hasattr(self, "checker_initiator_tag") \
180
 
               and self.checker_initiator_tag:
181
 
            gobject.source_remove(self.checker_initiator_tag)
182
 
            self.checker_initiator_tag = None
183
 
        self.stop_checker()
 
279
        self.stop_hook = None
 
280
        self.stop()
184
281
    def checker_callback(self, pid, condition):
185
282
        """The checker has completed, so take appropriate actions."""
186
283
        now = datetime.datetime.now()
 
284
        self.checker_callback_tag = None
 
285
        self.checker = None
187
286
        if os.WIFEXITED(condition) \
188
287
               and (os.WEXITSTATUS(condition) == 0):
189
 
            logger.debug(u"Checker for %(name)s succeeded",
190
 
                         vars(self))
191
 
            self.last_seen = now
 
288
            logger.info(u"Checker for %(name)s succeeded",
 
289
                        vars(self))
 
290
            self.last_checked_ok = now
192
291
            gobject.source_remove(self.stop_initiator_tag)
193
292
            self.stop_initiator_tag = gobject.timeout_add\
194
293
                                      (self._timeout_milliseconds,
195
294
                                       self.stop)
196
 
        if not os.WIFEXITED(condition):
 
295
        elif not os.WIFEXITED(condition):
197
296
            logger.warning(u"Checker for %(name)s crashed?",
198
297
                           vars(self))
199
298
        else:
200
 
            logger.debug(u"Checker for %(name)s failed",
201
 
                         vars(self))
202
 
            self.checker = None
203
 
        self.checker_callback_tag = None
 
299
            logger.info(u"Checker for %(name)s failed",
 
300
                        vars(self))
204
301
    def start_checker(self):
205
302
        """Start a new checker subprocess if one is not running.
206
303
        If a checker already exists, leave it running and do
207
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.
208
313
        if self.checker is None:
209
 
            logger.debug(u"Starting checker for %s",
210
 
                         self.name)
211
314
            try:
 
315
                # In case check_command has exactly one % operator
212
316
                command = self.check_command % self.fqdn
213
317
            except TypeError:
 
318
                # Escape attributes for the shell
214
319
                escaped_attrs = dict((key, re.escape(str(val)))
215
320
                                     for key, val in
216
321
                                     vars(self).iteritems())
217
322
                try:
218
323
                    command = self.check_command % escaped_attrs
219
324
                except TypeError, error:
220
 
                    logger.critical(u'Could not format string "%s": %s',
221
 
                                    self.check_command, error)
 
325
                    logger.error(u'Could not format string "%s":'
 
326
                                 u' %s', self.check_command, error)
222
327
                    return True # Try again later
223
328
            try:
224
 
                self.checker = subprocess.\
225
 
                               Popen(command,
226
 
                                     stdout=subprocess.PIPE,
227
 
                                     close_fds=True, shell=True,
228
 
                                     cwd="/")
229
 
                self.checker_callback_tag = gobject.\
230
 
                                            child_watch_add(self.checker.pid,
231
 
                                                            self.\
232
 
                                                            checker_callback)
 
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)
233
337
            except subprocess.OSError, error:
234
338
                logger.error(u"Failed to start subprocess: %s",
235
339
                             error)
237
341
        return True
238
342
    def stop_checker(self):
239
343
        """Force the checker process, if any, to stop."""
240
 
        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:
241
348
            return
242
 
        gobject.source_remove(self.checker_callback_tag)
243
 
        self.checker_callback_tag = None
244
 
        os.kill(self.checker.pid, signal.SIGTERM)
245
 
        if self.checker.poll() is None:
246
 
            os.kill(self.checker.pid, signal.SIGKILL)
 
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
247
358
        self.checker = None
248
 
    def still_valid(self, now=None):
 
359
    def still_valid(self):
249
360
        """Has the timeout not yet passed for this client?"""
250
 
        if now is None:
251
 
            now = datetime.datetime.now()
252
 
        if self.last_seen is None:
 
361
        now = datetime.datetime.now()
 
362
        if self.last_checked_ok is None:
253
363
            return now < (self.created + self.timeout)
254
364
        else:
255
 
            return now < (self.last_seen + self.timeout)
 
365
            return now < (self.last_checked_ok + self.timeout)
256
366
 
257
367
 
258
368
def peer_certificate(session):
 
369
    "Return the peer's OpenPGP certificate as a bytestring"
259
370
    # If not an OpenPGP certificate...
260
371
    if gnutls.library.functions.gnutls_certificate_type_get\
261
372
            (session._c_object) \
272
383
 
273
384
 
274
385
def fingerprint(openpgp):
275
 
    # New empty GnuTLS certificate
276
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
277
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
278
 
        (ctypes.byref(crt))
 
386
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
279
387
    # New GnuTLS "datum" with the OpenPGP public key
280
388
    datum = gnutls.library.types.gnutls_datum_t\
281
389
        (ctypes.cast(ctypes.c_char_p(openpgp),
282
390
                     ctypes.POINTER(ctypes.c_ubyte)),
283
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))
284
396
    # Import the OpenPGP public key into the certificate
285
 
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
286
 
        (crt,
287
 
         ctypes.byref(datum),
288
 
         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)
289
400
    # New buffer for the fingerprint
290
401
    buffer = ctypes.create_string_buffer(20)
291
402
    buffer_length = ctypes.c_size_t()
307
418
    Note: This will run in its own forked process."""
308
419
    
309
420
    def handle(self):
310
 
        logger.debug(u"TCP connection from: %s",
 
421
        logger.info(u"TCP connection from: %s",
311
422
                     unicode(self.client_address))
312
 
        session = gnutls.connection.ClientSession(self.request,
313
 
                                                  gnutls.connection.\
314
 
                                                  X509Credentials())
 
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.
315
439
        
316
440
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
317
441
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
318
442
        #                "+DHE-DSS"))
319
 
        priority = "SECURE256"
320
 
        
 
443
        priority = "NORMAL"             # Fallback default, since this
 
444
                                        # MUST be set.
 
445
        if self.server.settings["priority"]:
 
446
            priority = self.server.settings["priority"]
321
447
        gnutls.library.functions.gnutls_priority_set_direct\
322
448
            (session._c_object, priority, None);
323
449
        
324
450
        try:
325
451
            session.handshake()
326
452
        except gnutls.errors.GNUTLSError, error:
327
 
            logger.debug(u"Handshake failed: %s", error)
 
453
            logger.warning(u"Handshake failed: %s", error)
328
454
            # Do not run session.bye() here: the session is not
329
455
            # established.  Just abandon the request.
330
456
            return
331
457
        try:
332
458
            fpr = fingerprint(peer_certificate(session))
333
459
        except (TypeError, gnutls.errors.GNUTLSError), error:
334
 
            logger.debug(u"Bad certificate: %s", error)
 
460
            logger.warning(u"Bad certificate: %s", error)
335
461
            session.bye()
336
462
            return
337
463
        logger.debug(u"Fingerprint: %s", fpr)
338
464
        client = None
339
 
        for c in clients:
 
465
        for c in self.server.clients:
340
466
            if c.fingerprint == fpr:
341
467
                client = c
342
468
                break
 
469
        if not client:
 
470
            logger.warning(u"Client not found for fingerprint: %s",
 
471
                           fpr)
 
472
            session.bye()
 
473
            return
343
474
        # Have to check if client.still_valid(), since it is possible
344
475
        # that the client timed out while establishing the GnuTLS
345
476
        # session.
346
 
        if (not client) or (not client.still_valid()):
347
 
            if client:
348
 
                logger.debug(u"Client %(name)s is invalid",
349
 
                             vars(client))
350
 
            else:
351
 
                logger.debug(u"Client not found for fingerprint: %s",
352
 
                             fpr)
 
477
        if not client.still_valid():
 
478
            logger.warning(u"Client %(name)s is invalid",
 
479
                           vars(client))
353
480
            session.bye()
354
481
            return
355
482
        sent_size = 0
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
 
                    logger.warning(u"No permission to"
395
 
                                   u" bind to interface %s",
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
 
    logger.debug(u"Adding service '%s' of type '%s' ...",
457
 
                 serviceName, serviceType)
458
 
    
459
 
    group.AddService(
460
 
            serviceInterface,           # interface
461
 
            avahi.PROTO_INET6,          # protocol
462
 
            dbus.UInt32(0),             # flags
463
 
            serviceName, serviceType,
464
 
            domain, host,
465
 
            dbus.UInt16(servicePort),
466
 
            avahi.string_array_to_txt_array(serviceTXT))
467
 
    group.Commit()
468
 
 
469
 
 
470
 
def remove_service():
471
 
    """From the Avahi server example code"""
472
 
    global group
473
 
    
474
 
    if not group is None:
475
 
        group.Reset()
476
 
 
477
 
 
478
571
def server_state_changed(state):
479
 
    """From the Avahi server example code"""
 
572
    """Derived from the Avahi example code"""
480
573
    if state == avahi.SERVER_COLLISION:
481
 
        logger.warning(u"Server name collision")
482
 
        remove_service()
 
574
        logger.error(u"Server name collision")
 
575
        service.remove()
483
576
    elif state == avahi.SERVER_RUNNING:
484
 
        add_service()
 
577
        service.add()
485
578
 
486
579
 
487
580
def entry_group_state_changed(state, error):
488
 
    """From the Avahi server example code"""
489
 
    global serviceName, server, rename_count
490
 
    
 
581
    """Derived from the Avahi example code"""
491
582
    logger.debug(u"state change: %i", state)
492
583
    
493
584
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
494
585
        logger.debug(u"Service established.")
495
586
    elif state == avahi.ENTRY_GROUP_COLLISION:
496
 
        
497
 
        rename_count = rename_count - 1
498
 
        if rename_count > 0:
499
 
            name = server.GetAlternativeServiceName(name)
500
 
            logger.warning(u"Service name collision, "
501
 
                           u"changing name to '%s' ...", name)
502
 
            remove_service()
503
 
            add_service()
504
 
            
505
 
        else:
506
 
            logger.error(u"No suitable service name found "
507
 
                         u"after %i retries, exiting.",
508
 
                         n_rename)
509
 
            main_loop.quit()
 
587
        logger.warning(u"Service name collision.")
 
588
        service.rename()
510
589
    elif state == avahi.ENTRY_GROUP_FAILURE:
511
 
        logger.error(u"Error in group state changed %s",
512
 
                     unicode(error))
513
 
        main_loop.quit()
514
 
        return
515
 
 
 
590
        logger.critical(u"Error in group state changed %s",
 
591
                        unicode(error))
 
592
        raise AvahiGroupError("State changed: %s", str(error))
516
593
 
517
594
def if_nametoindex(interface):
518
 
    """Call the C function if_nametoindex()"""
 
595
    """Call the C function if_nametoindex(), or equivalent"""
 
596
    global if_nametoindex
519
597
    try:
520
 
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
521
 
        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
522
602
    except (OSError, AttributeError):
523
603
        if "struct" not in sys.modules:
524
604
            import struct
525
605
        if "fcntl" not in sys.modules:
526
606
            import fcntl
527
 
        SIOCGIFINDEX = 0x8933      # From /usr/include/linux/sockios.h
528
 
        s = socket.socket()
529
 
        ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
530
 
                            struct.pack("16s16x", interface))
531
 
        s.close()
532
 
        interface_index = struct.unpack("I", ifreq[16:20])[0]
533
 
        return interface_index
534
 
 
535
 
 
536
 
if __name__ == '__main__':
 
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
    
537
646
    parser = OptionParser()
538
647
    parser.add_option("-i", "--interface", type="string",
539
 
                      default=None, metavar="IF",
540
 
                      help="Bind to interface IF")
541
 
    parser.add_option("--cert", type="string", default="cert.pem",
542
 
                      metavar="FILE",
543
 
                      help="Public key certificate PEM file to use")
544
 
    parser.add_option("--key", type="string", default="key.pem",
545
 
                      metavar="FILE",
546
 
                      help="Private key PEM file to use")
547
 
    parser.add_option("--ca", type="string", default="ca.pem",
548
 
                      metavar="FILE",
549
 
                      help="Certificate Authority certificate PEM file to use")
550
 
    parser.add_option("--crl", type="string", default="crl.pem",
551
 
                      metavar="FILE",
552
 
                      help="Certificate Revokation List PEM file to use")
553
 
    parser.add_option("-p", "--port", type="int", default=None,
 
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",
554
652
                      help="Port number to receive requests on")
555
 
    parser.add_option("--timeout", type="string", # Parsed later
556
 
                      default="1h",
557
 
                      help="Amount of downtime allowed for clients")
558
 
    parser.add_option("--interval", type="string", # Parsed later
559
 
                      default="5m",
560
 
                      help="How often to check that a client is up")
561
653
    parser.add_option("--check", action="store_true", default=False,
562
654
                      help="Run self-test")
563
655
    parser.add_option("--debug", action="store_true", default=False,
564
 
                      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")
565
666
    (options, args) = parser.parse_args()
566
667
    
567
668
    if options.check:
569
670
        doctest.testmod()
570
671
        sys.exit()
571
672
    
572
 
    # Parse the time arguments
573
 
    try:
574
 
        options.timeout = string_to_delta(options.timeout)
575
 
    except ValueError:
576
 
        parser.error("option --timeout: Unparseable time")
577
 
    try:
578
 
        options.interval = string_to_delta(options.interval)
579
 
    except ValueError:
580
 
        parser.error("option --interval: Unparseable time")
581
 
    
582
 
    # Parse config file
583
 
    defaults = { "checker": "sleep 1; fping -q -- %%(fqdn)s" }
584
 
    client_config = ConfigParser.SafeConfigParser(defaults)
585
 
    #client_config.readfp(open("secrets.conf"), "secrets.conf")
586
 
    client_config.read("mandos-clients.conf")
587
 
    
588
 
    # From the Avahi server example code
 
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
589
724
    DBusGMainLoop(set_as_default=True )
590
725
    main_loop = gobject.MainLoop()
591
726
    bus = dbus.SystemBus()
594
729
            avahi.DBUS_INTERFACE_SERVER )
595
730
    # End of Avahi example code
596
731
    
597
 
    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
598
741
    
599
742
    clients = Set()
600
743
    def remove_from_clients(client):
601
744
        clients.remove(client)
602
745
        if not clients:
603
 
            logger.debug(u"No clients left, exiting")
604
 
            main_loop.quit()
 
746
            logger.critical(u"No clients left, exiting")
 
747
            sys.exit()
605
748
    
606
 
    clients.update(Set(Client(name=section, options=options,
 
749
    clients.update(Set(Client(name = section,
607
750
                              stop_hook = remove_from_clients,
608
 
                              **(dict(client_config\
609
 
                                      .items(section))))
 
751
                              config
 
752
                              = dict(client_config.items(section)))
610
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
    
611
779
    for client in clients:
612
780
        client.start()
613
781
    
614
 
    tcp_server = IPv6_TCPServer((None, options.port),
 
782
    tcp_server = IPv6_TCPServer((server_settings["address"],
 
783
                                 server_settings["port"]),
615
784
                                tcp_handler,
616
 
                                options=options,
 
785
                                settings=server_settings,
617
786
                                clients=clients)
618
 
    # Find out what random port we got
619
 
    servicePort = tcp_server.socket.getsockname()[1]
620
 
    logger.debug(u"Now listening on port %d", servicePort)
621
 
    
622
 
    if options.interface is not None:
623
 
        serviceInterface = if_nametoindex(options.interface)
624
 
    
625
 
    # From the Avahi server example code
626
 
    server.connect_to_signal("StateChanged", server_state_changed)
627
 
    server_state_changed(server.GetState())
628
 
    # End of Avahi example code
629
 
    
630
 
    gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
631
 
                         lambda *args, **kwargs:
632
 
                         tcp_server.handle_request(*args[2:],
633
 
                                                   **kwargs) or True)
 
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
    
634
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
635
811
        main_loop.run()
 
812
    except AvahiError, error:
 
813
        logger.critical(u"AvahiError: %s" + unicode(error))
 
814
        sys.exit(1)
636
815
    except KeyboardInterrupt:
637
 
        print
638
 
    
639
 
    # Cleanup here
 
816
        if debug:
 
817
            print
640
818
 
641
 
    # From the Avahi server example code
642
 
    if not group is None:
643
 
        group.Free()
644
 
    # End of Avahi example code
645
 
    
646
 
    for client in clients:
647
 
        client.stop_hook = None
648
 
        client.stop()
 
819
if __name__ == '__main__':
 
820
    main()