/mandos/release

To get this branch, use:
bzr branch http://bzr.recompile.se/loggerhead/mandos/release

« back to all changes in this revision

Viewing changes to server.py

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

Show diffs side-by-side

added added

removed removed

Lines of Context:
server.py
1
1
#!/usr/bin/python
2
 
# -*- mode: python; coding: utf-8 -*-
3
 
# 
4
 
# Mandos server - give out binary blobs to connecting clients.
5
 
# 
6
 
# This program is partly derived from an example program for an Avahi
7
 
# service publisher, downloaded from
8
 
# <http://avahi.org/wiki/PythonPublishExample>.  This includes the
9
 
# methods "add" and "remove" in the "AvahiService" class, the
10
 
# "server_state_changed" and "entry_group_state_changed" functions,
11
 
# and some lines in "main".
12
 
# 
13
 
# Everything else is
14
 
# Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
15
 
# 
16
 
# This program is free software: you can redistribute it and/or modify
17
 
# it under the terms of the GNU General Public License as published by
18
 
# the Free Software Foundation, either version 3 of the License, or
19
 
# (at your option) any later version.
20
 
#
21
 
#     This program is distributed in the hope that it will be useful,
22
 
#     but WITHOUT ANY WARRANTY; without even the implied warranty of
23
 
#     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24
 
#     GNU General Public License for more details.
25
 
# 
26
 
# You should have received a copy of the GNU General Public License
27
 
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
28
 
# 
29
 
# Contact the authors at <mandos@fukt.bsnet.se>.
30
 
# 
31
2
 
32
3
from __future__ import division
33
4
 
50
21
import signal
51
22
from sets import Set
52
23
import subprocess
53
 
import atexit
54
 
import stat
55
 
import logging
56
 
import logging.handlers
57
24
 
58
25
import dbus
59
26
import gobject
61
28
from dbus.mainloop.glib import DBusGMainLoop
62
29
import ctypes
63
30
 
 
31
import logging
 
32
import logging.handlers
 
33
 
 
34
# logghandler.setFormatter(logging.Formatter('%(levelname)s %(message)s')
64
35
 
65
36
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
 
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
156
53
# End of Avahi example code
157
54
 
158
55
 
164
61
                 uniquely identify the client
165
62
    secret:    bytestring; sent verbatim (over TLS) to client
166
63
    fqdn:      string (FQDN); available for use by the checker command
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
 
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
171
68
    interval:  datetime.timedelta(); How often to start a new checker
172
69
    stop_hook: If set, called by stop() as stop_hook(self)
173
70
    checker:   subprocess.Popen(); a running checker process used
174
71
                                   to see if the client lives.
175
 
                                   'None' if no process is running.
 
72
                                   Is None if no process is running.
176
73
    checker_initiator_tag: a gobject event source tag, or None
177
74
    stop_initiator_tag:    - '' -
178
75
    checker_callback_tag:  - '' -
179
76
    checker_command: string; External command which is run to check if
180
 
                     client lives.  %() expansions are done at
 
77
                     client lives.  %()s expansions are done at
181
78
                     runtime with vars(self) as dict, so that for
182
79
                     instance %(name)s can be used in the command.
183
80
    Private attibutes:
184
81
    _timeout: Real variable for 'timeout'
185
82
    _interval: Real variable for 'interval'
186
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
 
83
    _timeout_milliseconds: Used by gobject.timeout_add()
187
84
    _interval_milliseconds: - '' -
188
85
    """
189
86
    def _set_timeout(self, timeout):
209
106
    interval = property(lambda self: self._interval,
210
107
                        _set_interval)
211
108
    del _set_interval
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."""
 
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):
216
112
        self.name = name
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
        # 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)
228
121
            self.secret = sf.read()
229
122
            sf.close()
230
123
        else:
231
 
            raise TypeError(u"No secret or secfile for client %s"
232
 
                            % self.name)
233
 
        self.fqdn = config.get("fqdn", "")
 
124
            raise RuntimeError(u"No secret or secfile for client %s"
 
125
                               % self.name)
 
126
        self.fqdn = fqdn                # string
234
127
        self.created = datetime.datetime.now()
235
 
        self.last_checked_ok = None
236
 
        self.timeout = string_to_delta(config["timeout"])
237
 
        self.interval = string_to_delta(config["interval"])
 
128
        self.last_seen = None
 
129
        if timeout is None:
 
130
            timeout = options.timeout
 
131
        self.timeout = timeout
 
132
        if interval == -1:
 
133
            interval = options.interval
 
134
        else:
 
135
            interval = string_to_delta(interval)
 
136
        self.interval = interval
238
137
        self.stop_hook = stop_hook
239
138
        self.checker = None
240
139
        self.checker_initiator_tag = None
241
140
        self.stop_initiator_tag = None
242
141
        self.checker_callback_tag = None
243
 
        self.check_command = config["checker"]
 
142
        self.check_command = checker
244
143
    def start(self):
245
 
        """Start this client's checker and timeout hooks"""
 
144
        """Start this clients checker and timeout hooks"""
246
145
        # Schedule a new checker to be started an 'interval' from now,
247
146
        # and every interval from then on.
248
147
        self.checker_initiator_tag = gobject.timeout_add\
256
155
                                   self.stop)
257
156
    def stop(self):
258
157
        """Stop this client.
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):
 
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:
268
163
            gobject.source_remove(self.stop_initiator_tag)
269
164
            self.stop_initiator_tag = None
270
 
        if getattr(self, "checker_initiator_tag", False):
 
165
        if self.checker_initiator_tag:
271
166
            gobject.source_remove(self.checker_initiator_tag)
272
167
            self.checker_initiator_tag = None
273
168
        self.stop_checker()
276
171
        # Do not run this again if called by a gobject.timeout_add
277
172
        return False
278
173
    def __del__(self):
279
 
        self.stop_hook = None
280
 
        self.stop()
 
174
        # Some code duplication here and in stop()
 
175
        if hasattr(self, "stop_initiator_tag") \
 
176
               and self.stop_initiator_tag:
 
177
            gobject.source_remove(self.stop_initiator_tag)
 
178
            self.stop_initiator_tag = None
 
179
        if hasattr(self, "checker_initiator_tag") \
 
180
               and self.checker_initiator_tag:
 
181
            gobject.source_remove(self.checker_initiator_tag)
 
182
            self.checker_initiator_tag = None
 
183
        self.stop_checker()
281
184
    def checker_callback(self, pid, condition):
282
185
        """The checker has completed, so take appropriate actions."""
283
186
        now = datetime.datetime.now()
284
 
        self.checker_callback_tag = None
285
 
        self.checker = None
286
187
        if os.WIFEXITED(condition) \
287
188
               and (os.WEXITSTATUS(condition) == 0):
288
 
            logger.info(u"Checker for %(name)s succeeded",
289
 
                        vars(self))
290
 
            self.last_checked_ok = now
 
189
            logger.debug(u"Checker for %(name)s succeeded",
 
190
                         vars(self))
 
191
            self.last_seen = now
291
192
            gobject.source_remove(self.stop_initiator_tag)
292
193
            self.stop_initiator_tag = gobject.timeout_add\
293
194
                                      (self._timeout_milliseconds,
294
195
                                       self.stop)
295
 
        elif not os.WIFEXITED(condition):
 
196
        if not os.WIFEXITED(condition):
296
197
            logger.warning(u"Checker for %(name)s crashed?",
297
198
                           vars(self))
298
199
        else:
299
 
            logger.info(u"Checker for %(name)s failed",
300
 
                        vars(self))
 
200
            logger.debug(u"Checker for %(name)s failed",
 
201
                         vars(self))
 
202
            self.checker = None
 
203
        self.checker_callback_tag = None
301
204
    def start_checker(self):
302
205
        """Start a new checker subprocess if one is not running.
303
206
        If a checker already exists, leave it running and do
304
207
        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.
313
208
        if self.checker is None:
 
209
            logger.debug(u"Starting checker for %s",
 
210
                         self.name)
314
211
            try:
315
 
                # In case check_command has exactly one % operator
316
212
                command = self.check_command % self.fqdn
317
213
            except TypeError:
318
 
                # Escape attributes for the shell
319
214
                escaped_attrs = dict((key, re.escape(str(val)))
320
215
                                     for key, val in
321
216
                                     vars(self).iteritems())
322
217
                try:
323
218
                    command = self.check_command % escaped_attrs
324
219
                except TypeError, error:
325
 
                    logger.error(u'Could not format string "%s":'
326
 
                                 u' %s', self.check_command, error)
 
220
                    logger.critical(u'Could not format string "%s": %s',
 
221
                                    self.check_command, error)
327
222
                    return True # Try again later
328
223
            try:
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
                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)
337
233
            except subprocess.OSError, error:
338
234
                logger.error(u"Failed to start subprocess: %s",
339
235
                             error)
341
237
        return True
342
238
    def stop_checker(self):
343
239
        """Force the checker process, if any, to stop."""
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:
 
240
        if not hasattr(self, "checker") or self.checker is None:
348
241
            return
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
 
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)
358
247
        self.checker = None
359
 
    def still_valid(self):
 
248
    def still_valid(self, now=None):
360
249
        """Has the timeout not yet passed for this client?"""
361
 
        now = datetime.datetime.now()
362
 
        if self.last_checked_ok is None:
 
250
        if now is None:
 
251
            now = datetime.datetime.now()
 
252
        if self.last_seen is None:
363
253
            return now < (self.created + self.timeout)
364
254
        else:
365
 
            return now < (self.last_checked_ok + self.timeout)
 
255
            return now < (self.last_seen + self.timeout)
366
256
 
367
257
 
368
258
def peer_certificate(session):
369
 
    "Return the peer's OpenPGP certificate as a bytestring"
370
259
    # If not an OpenPGP certificate...
371
260
    if gnutls.library.functions.gnutls_certificate_type_get\
372
261
            (session._c_object) \
383
272
 
384
273
 
385
274
def fingerprint(openpgp):
386
 
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
 
275
    # New empty GnuTLS certificate
 
276
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
277
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
278
        (ctypes.byref(crt))
387
279
    # New GnuTLS "datum" with the OpenPGP public key
388
280
    datum = gnutls.library.types.gnutls_datum_t\
389
281
        (ctypes.cast(ctypes.c_char_p(openpgp),
390
282
                     ctypes.POINTER(ctypes.c_ubyte)),
391
283
         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))
396
284
    # Import the OpenPGP public key into the certificate
397
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
398
 
                    (crt, ctypes.byref(datum),
399
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
 
285
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
 
286
        (crt,
 
287
         ctypes.byref(datum),
 
288
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
400
289
    # New buffer for the fingerprint
401
290
    buffer = ctypes.create_string_buffer(20)
402
291
    buffer_length = ctypes.c_size_t()
418
307
    Note: This will run in its own forked process."""
419
308
    
420
309
    def handle(self):
421
 
        logger.info(u"TCP connection from: %s",
 
310
        logger.debug(u"TCP connection from: %s",
422
311
                     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.
 
312
        session = gnutls.connection.ClientSession(self.request,
 
313
                                                  gnutls.connection.\
 
314
                                                  X509Credentials())
439
315
        
440
316
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
441
317
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
442
318
        #                "+DHE-DSS"))
443
 
        priority = "NORMAL"             # Fallback default, since this
444
 
                                        # MUST be set.
445
 
        if self.server.settings["priority"]:
446
 
            priority = self.server.settings["priority"]
 
319
        priority = "SECURE256"
 
320
        
447
321
        gnutls.library.functions.gnutls_priority_set_direct\
448
322
            (session._c_object, priority, None);
449
323
        
450
324
        try:
451
325
            session.handshake()
452
326
        except gnutls.errors.GNUTLSError, error:
453
 
            logger.warning(u"Handshake failed: %s", error)
 
327
            logger.debug(u"Handshake failed: %s", error)
454
328
            # Do not run session.bye() here: the session is not
455
329
            # established.  Just abandon the request.
456
330
            return
457
331
        try:
458
332
            fpr = fingerprint(peer_certificate(session))
459
333
        except (TypeError, gnutls.errors.GNUTLSError), error:
460
 
            logger.warning(u"Bad certificate: %s", error)
 
334
            logger.debug(u"Bad certificate: %s", error)
461
335
            session.bye()
462
336
            return
463
337
        logger.debug(u"Fingerprint: %s", fpr)
464
338
        client = None
465
 
        for c in self.server.clients:
 
339
        for c in clients:
466
340
            if c.fingerprint == fpr:
467
341
                client = c
468
342
                break
469
 
        if not client:
470
 
            logger.warning(u"Client not found for fingerprint: %s",
471
 
                           fpr)
472
 
            session.bye()
473
 
            return
474
343
        # Have to check if client.still_valid(), since it is possible
475
344
        # that the client timed out while establishing the GnuTLS
476
345
        # session.
477
 
        if not client.still_valid():
478
 
            logger.warning(u"Client %(name)s is invalid",
479
 
                           vars(client))
 
346
        if (not client) or (not client.still_valid()):
 
347
            if client:
 
348
                logger.debug(u"Client %(name)s is invalid",
 
349
                             vars(client))
 
350
            else:
 
351
                logger.debug(u"Client not found for fingerprint: %s",
 
352
                             fpr)
480
353
            session.bye()
481
354
            return
482
355
        sent_size = 0
492
365
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
493
366
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
494
367
    Attributes:
495
 
        settings:       Server settings
 
368
        options:        Command line options
496
369
        clients:        Set() of Client objects
497
370
    """
498
371
    address_family = socket.AF_INET6
499
372
    def __init__(self, *args, **kwargs):
500
 
        if "settings" in kwargs:
501
 
            self.settings = kwargs["settings"]
502
 
            del kwargs["settings"]
 
373
        if "options" in kwargs:
 
374
            self.options = kwargs["options"]
 
375
            del kwargs["options"]
503
376
        if "clients" in kwargs:
504
377
            self.clients = kwargs["clients"]
505
378
            del kwargs["clients"]
508
381
        """This overrides the normal server_bind() function
509
382
        to bind to an interface if one was specified, and also NOT to
510
383
        bind to an address or port if they were not specified."""
511
 
        if self.settings["interface"]:
512
 
            # 25 is from /usr/include/asm-i486/socket.h
513
 
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
 
384
        if self.options.interface:
 
385
            if not hasattr(socket, "SO_BINDTODEVICE"):
 
386
                # From /usr/include/asm-i486/socket.h
 
387
                socket.SO_BINDTODEVICE = 25
514
388
            try:
515
389
                self.socket.setsockopt(socket.SOL_SOCKET,
516
 
                                       SO_BINDTODEVICE,
517
 
                                       self.settings["interface"])
 
390
                                       socket.SO_BINDTODEVICE,
 
391
                                       self.options.interface)
518
392
            except socket.error, error:
519
393
                if error[0] == errno.EPERM:
520
 
                    logger.error(u"No permission to"
521
 
                                 u" bind to interface %s",
522
 
                                 self.settings["interface"])
 
394
                    logger.warning(u"No permission to"
 
395
                                   u" bind to interface %s",
 
396
                                   self.options.interface)
523
397
                else:
524
398
                    raise error
525
399
        # Only bind(2) the socket if we really need to.
528
402
                in6addr_any = "::"
529
403
                self.server_address = (in6addr_any,
530
404
                                       self.server_address[1])
531
 
            elif not self.server_address[1]:
 
405
            elif self.server_address[1] is None:
532
406
                self.server_address = (self.server_address[0],
533
407
                                       0)
534
 
#                 if self.settings["interface"]:
535
 
#                     self.server_address = (self.server_address[0],
536
 
#                                            0, # port
537
 
#                                            0, # flowinfo
538
 
#                                            if_nametoindex
539
 
#                                            (self.settings
540
 
#                                             ["interface"]))
541
408
            return super(type(self), self).server_bind()
542
409
 
543
410
 
575
442
    return delta
576
443
 
577
444
 
 
445
def add_service():
 
446
    """From the Avahi server example code"""
 
447
    global group, serviceName, serviceType, servicePort, serviceTXT, \
 
448
           domain, host
 
449
    if group is None:
 
450
        group = dbus.Interface(
 
451
                bus.get_object( avahi.DBUS_NAME,
 
452
                                server.EntryGroupNew()),
 
453
                avahi.DBUS_INTERFACE_ENTRY_GROUP)
 
454
        group.connect_to_signal('StateChanged',
 
455
                                entry_group_state_changed)
 
456
    logger.debug(u"Adding service '%s' of type '%s' ...",
 
457
                 serviceName, serviceType)
 
458
    
 
459
    group.AddService(
 
460
            serviceInterface,           # interface
 
461
            avahi.PROTO_INET6,          # protocol
 
462
            dbus.UInt32(0),             # flags
 
463
            serviceName, serviceType,
 
464
            domain, host,
 
465
            dbus.UInt16(servicePort),
 
466
            avahi.string_array_to_txt_array(serviceTXT))
 
467
    group.Commit()
 
468
 
 
469
 
 
470
def remove_service():
 
471
    """From the Avahi server example code"""
 
472
    global group
 
473
    
 
474
    if not group is None:
 
475
        group.Reset()
 
476
 
 
477
 
578
478
def server_state_changed(state):
579
 
    """Derived from the Avahi example code"""
 
479
    """From the Avahi server example code"""
580
480
    if state == avahi.SERVER_COLLISION:
581
 
        logger.error(u"Server name collision")
582
 
        service.remove()
 
481
        logger.warning(u"Server name collision")
 
482
        remove_service()
583
483
    elif state == avahi.SERVER_RUNNING:
584
 
        service.add()
 
484
        add_service()
585
485
 
586
486
 
587
487
def entry_group_state_changed(state, error):
588
 
    """Derived from the Avahi example code"""
 
488
    """From the Avahi server example code"""
 
489
    global serviceName, server, rename_count
 
490
    
589
491
    logger.debug(u"state change: %i", state)
590
492
    
591
493
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
592
494
        logger.debug(u"Service established.")
593
495
    elif state == avahi.ENTRY_GROUP_COLLISION:
594
 
        logger.warning(u"Service name collision.")
595
 
        service.rename()
 
496
        
 
497
        rename_count = rename_count - 1
 
498
        if rename_count > 0:
 
499
            name = server.GetAlternativeServiceName(name)
 
500
            logger.warning(u"Service name collision, "
 
501
                           u"changing name to '%s' ...", name)
 
502
            remove_service()
 
503
            add_service()
 
504
            
 
505
        else:
 
506
            logger.error(u"No suitable service name found "
 
507
                         u"after %i retries, exiting.",
 
508
                         n_rename)
 
509
            main_loop.quit()
596
510
    elif state == avahi.ENTRY_GROUP_FAILURE:
597
 
        logger.critical(u"Error in group state changed %s",
598
 
                        unicode(error))
599
 
        raise AvahiGroupError("State changed: %s", str(error))
 
511
        logger.error(u"Error in group state changed %s",
 
512
                     unicode(error))
 
513
        main_loop.quit()
 
514
        return
 
515
 
600
516
 
601
517
def if_nametoindex(interface):
602
 
    """Call the C function if_nametoindex(), or equivalent"""
603
 
    global if_nametoindex
 
518
    """Call the C function if_nametoindex()"""
604
519
    try:
605
 
        if "ctypes.util" not in sys.modules:
606
 
            import ctypes.util
607
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
608
 
            (ctypes.util.find_library("c")).if_nametoindex
 
520
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
 
521
        return libc.if_nametoindex(interface)
609
522
    except (OSError, AttributeError):
610
523
        if "struct" not in sys.modules:
611
524
            import struct
612
525
        if "fcntl" not in sys.modules:
613
526
            import fcntl
614
 
        def if_nametoindex(interface):
615
 
            "Get an interface index the hard way, i.e. using fcntl()"
616
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
617
 
            s = socket.socket()
618
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
619
 
                                struct.pack("16s16x", interface))
620
 
            s.close()
621
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
622
 
            return interface_index
623
 
    return if_nametoindex(interface)
624
 
 
625
 
 
626
 
def daemon(nochdir = False, noclose = False):
627
 
    """See daemon(3).  Standard BSD Unix function.
628
 
    This should really exist as os.daemon, but it doesn't (yet)."""
629
 
    if os.fork():
630
 
        sys.exit()
631
 
    os.setsid()
632
 
    if not nochdir:
633
 
        os.chdir("/")
634
 
    if os.fork():
635
 
        sys.exit()
636
 
    if not noclose:
637
 
        # Close all standard open file descriptors
638
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
639
 
        if not stat.S_ISCHR(os.fstat(null).st_mode):
640
 
            raise OSError(errno.ENODEV,
641
 
                          "/dev/null not a character device")
642
 
        os.dup2(null, sys.stdin.fileno())
643
 
        os.dup2(null, sys.stdout.fileno())
644
 
        os.dup2(null, sys.stderr.fileno())
645
 
        if null > 2:
646
 
            os.close(null)
647
 
 
648
 
 
649
 
def main():
650
 
    global main_loop_started
651
 
    main_loop_started = False
652
 
    
 
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__':
653
537
    parser = OptionParser()
654
538
    parser.add_option("-i", "--interface", type="string",
655
 
                      metavar="IF", help="Bind to interface IF")
656
 
    parser.add_option("-a", "--address", type="string",
657
 
                      help="Address to listen for requests on")
658
 
    parser.add_option("-p", "--port", type="int",
 
539
                      default=None, metavar="IF",
 
540
                      help="Bind to interface IF")
 
541
    parser.add_option("--cert", type="string", default="cert.pem",
 
542
                      metavar="FILE",
 
543
                      help="Public key certificate PEM file to use")
 
544
    parser.add_option("--key", type="string", default="key.pem",
 
545
                      metavar="FILE",
 
546
                      help="Private key PEM file to use")
 
547
    parser.add_option("--ca", type="string", default="ca.pem",
 
548
                      metavar="FILE",
 
549
                      help="Certificate Authority certificate PEM file to use")
 
550
    parser.add_option("--crl", type="string", default="crl.pem",
 
551
                      metavar="FILE",
 
552
                      help="Certificate Revokation List PEM file to use")
 
553
    parser.add_option("-p", "--port", type="int", default=None,
659
554
                      help="Port number to receive requests on")
 
555
    parser.add_option("--timeout", type="string", # Parsed later
 
556
                      default="1h",
 
557
                      help="Amount of downtime allowed for clients")
 
558
    parser.add_option("--interval", type="string", # Parsed later
 
559
                      default="5m",
 
560
                      help="How often to check that a client is up")
660
561
    parser.add_option("--check", action="store_true", default=False,
661
562
                      help="Run self-test")
662
 
    parser.add_option("--debug", action="store_true",
663
 
                      help="Debug mode; run in foreground and log to"
664
 
                      " terminal")
665
 
    parser.add_option("--priority", type="string", help="GnuTLS"
666
 
                      " priority string (see GnuTLS documentation)")
667
 
    parser.add_option("--servicename", type="string", metavar="NAME",
668
 
                      help="Zeroconf service name")
669
 
    parser.add_option("--configdir", type="string",
670
 
                      default="/etc/mandos", metavar="DIR",
671
 
                      help="Directory to search for configuration"
672
 
                      " files")
 
563
    parser.add_option("--debug", action="store_true", default=False,
 
564
                      help="Debug mode")
673
565
    (options, args) = parser.parse_args()
674
566
    
675
567
    if options.check:
677
569
        doctest.testmod()
678
570
        sys.exit()
679
571
    
680
 
    # Default values for config file for server-global settings
681
 
    server_defaults = { "interface": "",
682
 
                        "address": "",
683
 
                        "port": "",
684
 
                        "debug": "False",
685
 
                        "priority":
686
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
687
 
                        "servicename": "Mandos",
688
 
                        }
689
 
    
690
 
    # Parse config file for server-global settings
691
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
692
 
    del server_defaults
693
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
694
 
    server_section = "server"
695
 
    # Convert the SafeConfigParser object to a dict
696
 
    server_settings = dict(server_config.items(server_section))
697
 
    # Use getboolean on the boolean config option
698
 
    server_settings["debug"] = server_config.getboolean\
699
 
                               (server_section, "debug")
700
 
    del server_config
701
 
    
702
 
    # Override the settings from the config file with command line
703
 
    # options, if set.
704
 
    for option in ("interface", "address", "port", "debug",
705
 
                   "priority", "servicename", "configdir"):
706
 
        value = getattr(options, option)
707
 
        if value is not None:
708
 
            server_settings[option] = value
709
 
    del options
710
 
    # Now we have our good server settings in "server_settings"
711
 
    
712
 
    # Parse config file with clients
713
 
    client_defaults = { "timeout": "1h",
714
 
                        "interval": "5m",
715
 
                        "checker": "fping -q -- %%(fqdn)s",
716
 
                        }
717
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
718
 
    client_config.read(os.path.join(server_settings["configdir"],
719
 
                                    "clients.conf"))
720
 
    
721
 
    global service
722
 
    service = AvahiService(name = server_settings["servicename"],
723
 
                           type = "_mandos._tcp", );
724
 
    if server_settings["interface"]:
725
 
        service.interface = if_nametoindex(server_settings["interface"])
726
 
    
727
 
    global main_loop
728
 
    global bus
729
 
    global server
730
 
    # From the Avahi example code
 
572
    # Parse the time arguments
 
573
    try:
 
574
        options.timeout = string_to_delta(options.timeout)
 
575
    except ValueError:
 
576
        parser.error("option --timeout: Unparseable time")
 
577
    try:
 
578
        options.interval = string_to_delta(options.interval)
 
579
    except ValueError:
 
580
        parser.error("option --interval: Unparseable time")
 
581
    
 
582
    # Parse config file
 
583
    defaults = { "checker": "sleep 1; fping -q -- %%(fqdn)s" }
 
584
    client_config = ConfigParser.SafeConfigParser(defaults)
 
585
    #client_config.readfp(open("secrets.conf"), "secrets.conf")
 
586
    client_config.read("mandos-clients.conf")
 
587
    
 
588
    # From the Avahi server example code
731
589
    DBusGMainLoop(set_as_default=True )
732
590
    main_loop = gobject.MainLoop()
733
591
    bus = dbus.SystemBus()
736
594
            avahi.DBUS_INTERFACE_SERVER )
737
595
    # End of Avahi example code
738
596
    
739
 
    debug = server_settings["debug"]
740
 
    
741
 
    if debug:
742
 
        console = logging.StreamHandler()
743
 
        # console.setLevel(logging.DEBUG)
744
 
        console.setFormatter(logging.Formatter\
745
 
                             ('%(levelname)s: %(message)s'))
746
 
        logger.addHandler(console)
747
 
        del console
 
597
    debug = options.debug
748
598
    
749
599
    clients = Set()
750
600
    def remove_from_clients(client):
751
601
        clients.remove(client)
752
602
        if not clients:
753
 
            logger.critical(u"No clients left, exiting")
754
 
            sys.exit()
 
603
            logger.debug(u"No clients left, exiting")
 
604
            main_loop.quit()
755
605
    
756
 
    clients.update(Set(Client(name = section,
 
606
    clients.update(Set(Client(name=section, options=options,
757
607
                              stop_hook = remove_from_clients,
758
 
                              config
759
 
                              = dict(client_config.items(section)))
 
608
                              **(dict(client_config\
 
609
                                      .items(section))))
760
610
                       for section in client_config.sections()))
761
 
    
762
 
    if not debug:
763
 
        daemon()
764
 
    
765
 
    def cleanup():
766
 
        "Cleanup function; run on exit"
767
 
        global group
768
 
        # From the Avahi example code
769
 
        if not group is None:
770
 
            group.Free()
771
 
            group = None
772
 
        # End of Avahi example code
773
 
        
774
 
        while clients:
775
 
            client = clients.pop()
776
 
            client.stop_hook = None
777
 
            client.stop()
778
 
    
779
 
    atexit.register(cleanup)
780
 
    
781
 
    if not debug:
782
 
        signal.signal(signal.SIGINT, signal.SIG_IGN)
783
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
784
 
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
785
 
    
786
611
    for client in clients:
787
612
        client.start()
788
613
    
789
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
790
 
                                 server_settings["port"]),
 
614
    tcp_server = IPv6_TCPServer((None, options.port),
791
615
                                tcp_handler,
792
 
                                settings=server_settings,
 
616
                                options=options,
793
617
                                clients=clients)
794
 
    # Find out what port we got
795
 
    service.port = tcp_server.socket.getsockname()[1]
796
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
797
 
                u" scope_id %d" % tcp_server.socket.getsockname())
798
 
    
799
 
    #service.interface = tcp_server.socket.getsockname()[3]
800
 
    
 
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)
801
634
    try:
802
 
        # From the Avahi example code
803
 
        server.connect_to_signal("StateChanged", server_state_changed)
804
 
        try:
805
 
            server_state_changed(server.GetState())
806
 
        except dbus.exceptions.DBusException, error:
807
 
            logger.critical(u"DBusException: %s", error)
808
 
            sys.exit(1)
809
 
        # End of Avahi example code
810
 
        
811
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
812
 
                             lambda *args, **kwargs:
813
 
                             tcp_server.handle_request\
814
 
                             (*args[2:], **kwargs) or True)
815
 
        
816
 
        logger.debug("Starting main loop")
817
 
        main_loop_started = True
818
635
        main_loop.run()
819
 
    except AvahiError, error:
820
 
        logger.critical(u"AvahiError: %s" + unicode(error))
821
 
        sys.exit(1)
822
636
    except KeyboardInterrupt:
823
 
        if debug:
824
 
            print
 
637
        print
 
638
    
 
639
    # Cleanup here
825
640
 
826
 
if __name__ == '__main__':
827
 
    main()
 
641
    # From the Avahi server example code
 
642
    if not group is None:
 
643
        group.Free()
 
644
    # End of Avahi example code
 
645
    
 
646
    for client in clients:
 
647
        client.stop_hook = None
 
648
        client.stop()