/mandos/trunk

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

« 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
 
64
 
version = "1.0"
 
31
import logging
 
32
import logging.handlers
 
33
 
 
34
# logghandler.setFormatter(logging.Formatter('%(levelname)s %(message)s')
65
35
 
66
36
logger = logging.Logger('mandos')
67
 
syslogger = logging.handlers.SysLogHandler\
68
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
69
 
             address = "/dev/log")
70
 
syslogger.setFormatter(logging.Formatter\
71
 
                        ('Mandos: %(levelname)s: %(message)s'))
72
 
logger.addHandler(syslogger)
73
 
 
74
 
console = logging.StreamHandler()
75
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
76
 
                                       ' %(message)s'))
77
 
logger.addHandler(console)
78
 
 
79
 
class AvahiError(Exception):
80
 
    def __init__(self, value):
81
 
        self.value = value
82
 
    def __str__(self):
83
 
        return repr(self.value)
84
 
 
85
 
class AvahiServiceError(AvahiError):
86
 
    pass
87
 
 
88
 
class AvahiGroupError(AvahiError):
89
 
    pass
90
 
 
91
 
 
92
 
class AvahiService(object):
93
 
    """An Avahi (Zeroconf) service.
94
 
    Attributes:
95
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
96
 
               Used to optionally bind to the specified interface.
97
 
    name: string; Example: 'Mandos'
98
 
    type: string; Example: '_mandos._tcp'.
99
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
100
 
    port: integer; what port to announce
101
 
    TXT: list of strings; TXT record for the service
102
 
    domain: string; Domain to publish on, default to .local if empty.
103
 
    host: string; Host to publish records for, default is localhost
104
 
    max_renames: integer; maximum number of renames
105
 
    rename_count: integer; counter so we only rename after collisions
106
 
                  a sensible number of times
107
 
    """
108
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
109
 
                 type = None, port = None, TXT = None, domain = "",
110
 
                 host = "", max_renames = 32768):
111
 
        self.interface = interface
112
 
        self.name = name
113
 
        self.type = type
114
 
        self.port = port
115
 
        if TXT is None:
116
 
            self.TXT = []
117
 
        else:
118
 
            self.TXT = TXT
119
 
        self.domain = domain
120
 
        self.host = host
121
 
        self.rename_count = 0
122
 
        self.max_renames = max_renames
123
 
    def rename(self):
124
 
        """Derived from the Avahi example code"""
125
 
        if self.rename_count >= self.max_renames:
126
 
            logger.critical(u"No suitable service name found after %i"
127
 
                            u" retries, exiting.", rename_count)
128
 
            raise AvahiServiceError("Too many renames")
129
 
        self.name = server.GetAlternativeServiceName(self.name)
130
 
        logger.info(u"Changing name to %r ...", str(self.name))
131
 
        syslogger.setFormatter(logging.Formatter\
132
 
                               ('Mandos (%s): %%(levelname)s:'
133
 
                               ' %%(message)s' % self.name))
134
 
        self.remove()
135
 
        self.add()
136
 
        self.rename_count += 1
137
 
    def remove(self):
138
 
        """Derived from the Avahi example code"""
139
 
        if group is not None:
140
 
            group.Reset()
141
 
    def add(self):
142
 
        """Derived from the Avahi example code"""
143
 
        global group
144
 
        if group is None:
145
 
            group = dbus.Interface\
146
 
                    (bus.get_object(avahi.DBUS_NAME,
147
 
                                    server.EntryGroupNew()),
148
 
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
149
 
            group.connect_to_signal('StateChanged',
150
 
                                    entry_group_state_changed)
151
 
        logger.debug(u"Adding service '%s' of type '%s' ...",
152
 
                     service.name, service.type)
153
 
        group.AddService(
154
 
                self.interface,         # interface
155
 
                avahi.PROTO_INET6,      # protocol
156
 
                dbus.UInt32(0),         # flags
157
 
                self.name, self.type,
158
 
                self.domain, self.host,
159
 
                dbus.UInt16(self.port),
160
 
                avahi.string_array_to_txt_array(self.TXT))
161
 
        group.Commit()
162
 
 
163
 
# From the Avahi example code:
164
 
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
165
53
# End of Avahi example code
166
54
 
167
55
 
172
60
    fingerprint: string (40 or 32 hexadecimal digits); used to
173
61
                 uniquely identify the client
174
62
    secret:    bytestring; sent verbatim (over TLS) to client
175
 
    host:      string; available for use by the checker command
176
 
    created:   datetime.datetime(); object creation, not client host
177
 
    last_checked_ok: datetime.datetime() or None if not yet checked OK
178
 
    timeout:   datetime.timedelta(); How long from last_checked_ok
179
 
                                     until this client is invalid
 
63
    fqdn:      string (FQDN); available for use by the checker command
 
64
    created:   datetime.datetime()
 
65
    last_seen: datetime.datetime() or None if not yet seen
 
66
    timeout:   datetime.timedelta(); How long from last_seen until
 
67
                                     this client is invalid
180
68
    interval:  datetime.timedelta(); How often to start a new checker
181
69
    stop_hook: If set, called by stop() as stop_hook(self)
182
70
    checker:   subprocess.Popen(); a running checker process used
183
71
                                   to see if the client lives.
184
 
                                   'None' if no process is running.
 
72
                                   Is None if no process is running.
185
73
    checker_initiator_tag: a gobject event source tag, or None
186
74
    stop_initiator_tag:    - '' -
187
75
    checker_callback_tag:  - '' -
188
76
    checker_command: string; External command which is run to check if
189
 
                     client lives.  %() expansions are done at
 
77
                     client lives.  %()s expansions are done at
190
78
                     runtime with vars(self) as dict, so that for
191
79
                     instance %(name)s can be used in the command.
192
80
    Private attibutes:
193
81
    _timeout: Real variable for 'timeout'
194
82
    _interval: Real variable for 'interval'
195
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
 
83
    _timeout_milliseconds: Used by gobject.timeout_add()
196
84
    _interval_milliseconds: - '' -
197
85
    """
198
86
    def _set_timeout(self, timeout):
218
106
    interval = property(lambda self: self._interval,
219
107
                        _set_interval)
220
108
    del _set_interval
221
 
    def __init__(self, name = None, stop_hook=None, config={}):
222
 
        """Note: the 'checker' key in 'config' sets the
223
 
        'checker_command' attribute and *not* the 'checker'
224
 
        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):
225
112
        self.name = name
226
 
        logger.debug(u"Creating client %r", self.name)
227
 
        # Uppercase and remove spaces from fingerprint for later
228
 
        # comparison purposes with return value from the fingerprint()
229
 
        # function
230
 
        self.fingerprint = config["fingerprint"].upper()\
231
 
                           .replace(u" ", u"")
232
 
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
233
 
        if "secret" in config:
234
 
            self.secret = config["secret"].decode(u"base64")
235
 
        elif "secfile" in config:
236
 
            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)
237
121
            self.secret = sf.read()
238
122
            sf.close()
239
123
        else:
240
 
            raise TypeError(u"No secret or secfile for client %s"
241
 
                            % self.name)
242
 
        self.host = config.get("host", "")
 
124
            raise RuntimeError(u"No secret or secfile for client %s"
 
125
                               % self.name)
 
126
        self.fqdn = fqdn                # string
243
127
        self.created = datetime.datetime.now()
244
 
        self.last_checked_ok = None
245
 
        self.timeout = string_to_delta(config["timeout"])
246
 
        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
247
137
        self.stop_hook = stop_hook
248
138
        self.checker = None
249
139
        self.checker_initiator_tag = None
250
140
        self.stop_initiator_tag = None
251
141
        self.checker_callback_tag = None
252
 
        self.check_command = config["checker"]
 
142
        self.check_command = checker
253
143
    def start(self):
254
 
        """Start this client's checker and timeout hooks"""
 
144
        """Start this clients checker and timeout hooks"""
255
145
        # Schedule a new checker to be started an 'interval' from now,
256
146
        # and every interval from then on.
257
147
        self.checker_initiator_tag = gobject.timeout_add\
265
155
                                   self.stop)
266
156
    def stop(self):
267
157
        """Stop this client.
268
 
        The possibility that a client might be restarted is left open,
269
 
        but not currently used."""
270
 
        # If this client doesn't have a secret, it is already stopped.
271
 
        if hasattr(self, "secret") and self.secret:
272
 
            logger.info(u"Stopping client %s", self.name)
273
 
            self.secret = None
274
 
        else:
275
 
            return False
276
 
        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:
277
163
            gobject.source_remove(self.stop_initiator_tag)
278
164
            self.stop_initiator_tag = None
279
 
        if getattr(self, "checker_initiator_tag", False):
 
165
        if self.checker_initiator_tag:
280
166
            gobject.source_remove(self.checker_initiator_tag)
281
167
            self.checker_initiator_tag = None
282
168
        self.stop_checker()
285
171
        # Do not run this again if called by a gobject.timeout_add
286
172
        return False
287
173
    def __del__(self):
288
 
        self.stop_hook = None
289
 
        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()
290
184
    def checker_callback(self, pid, condition):
291
185
        """The checker has completed, so take appropriate actions."""
292
186
        now = datetime.datetime.now()
293
 
        self.checker_callback_tag = None
294
 
        self.checker = None
295
187
        if os.WIFEXITED(condition) \
296
188
               and (os.WEXITSTATUS(condition) == 0):
297
 
            logger.info(u"Checker for %(name)s succeeded",
298
 
                        vars(self))
299
 
            self.last_checked_ok = now
 
189
            logger.debug(u"Checker for %(name)s succeeded",
 
190
                         vars(self))
 
191
            self.last_seen = now
300
192
            gobject.source_remove(self.stop_initiator_tag)
301
193
            self.stop_initiator_tag = gobject.timeout_add\
302
194
                                      (self._timeout_milliseconds,
303
195
                                       self.stop)
304
 
        elif not os.WIFEXITED(condition):
 
196
        if not os.WIFEXITED(condition):
305
197
            logger.warning(u"Checker for %(name)s crashed?",
306
198
                           vars(self))
307
199
        else:
308
 
            logger.info(u"Checker for %(name)s failed",
309
 
                        vars(self))
 
200
            logger.debug(u"Checker for %(name)s failed",
 
201
                         vars(self))
 
202
            self.checker = None
 
203
        self.checker_callback_tag = None
310
204
    def start_checker(self):
311
205
        """Start a new checker subprocess if one is not running.
312
206
        If a checker already exists, leave it running and do
313
207
        nothing."""
314
 
        # The reason for not killing a running checker is that if we
315
 
        # did that, then if a checker (for some reason) started
316
 
        # running slowly and taking more than 'interval' time, the
317
 
        # client would inevitably timeout, since no checker would get
318
 
        # a chance to run to completion.  If we instead leave running
319
 
        # checkers alone, the checker would have to take more time
320
 
        # than 'timeout' for the client to be declared invalid, which
321
 
        # is as it should be.
322
208
        if self.checker is None:
 
209
            logger.debug(u"Starting checker for %s",
 
210
                         self.name)
323
211
            try:
324
 
                # In case check_command has exactly one % operator
325
 
                command = self.check_command % self.host
 
212
                command = self.check_command % self.fqdn
326
213
            except TypeError:
327
 
                # Escape attributes for the shell
328
214
                escaped_attrs = dict((key, re.escape(str(val)))
329
215
                                     for key, val in
330
216
                                     vars(self).iteritems())
331
217
                try:
332
218
                    command = self.check_command % escaped_attrs
333
219
                except TypeError, error:
334
 
                    logger.error(u'Could not format string "%s":'
335
 
                                 u' %s', self.check_command, error)
 
220
                    logger.critical(u'Could not format string "%s": %s',
 
221
                                    self.check_command, error)
336
222
                    return True # Try again later
337
223
            try:
338
 
                logger.info(u"Starting checker %r for %s",
339
 
                            command, self.name)
340
 
                self.checker = subprocess.Popen(command,
341
 
                                                close_fds=True,
342
 
                                                shell=True, cwd="/")
343
 
                self.checker_callback_tag = gobject.child_watch_add\
344
 
                                            (self.checker.pid,
345
 
                                             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)
346
233
            except subprocess.OSError, error:
347
234
                logger.error(u"Failed to start subprocess: %s",
348
235
                             error)
350
237
        return True
351
238
    def stop_checker(self):
352
239
        """Force the checker process, if any, to stop."""
353
 
        if self.checker_callback_tag:
354
 
            gobject.source_remove(self.checker_callback_tag)
355
 
            self.checker_callback_tag = None
356
 
        if getattr(self, "checker", None) is None:
 
240
        if not hasattr(self, "checker") or self.checker is None:
357
241
            return
358
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
359
 
        try:
360
 
            os.kill(self.checker.pid, signal.SIGTERM)
361
 
            #os.sleep(0.5)
362
 
            #if self.checker.poll() is None:
363
 
            #    os.kill(self.checker.pid, signal.SIGKILL)
364
 
        except OSError, error:
365
 
            if error.errno != errno.ESRCH: # No such process
366
 
                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)
367
247
        self.checker = None
368
 
    def still_valid(self):
 
248
    def still_valid(self, now=None):
369
249
        """Has the timeout not yet passed for this client?"""
370
 
        now = datetime.datetime.now()
371
 
        if self.last_checked_ok is None:
 
250
        if now is None:
 
251
            now = datetime.datetime.now()
 
252
        if self.last_seen is None:
372
253
            return now < (self.created + self.timeout)
373
254
        else:
374
 
            return now < (self.last_checked_ok + self.timeout)
 
255
            return now < (self.last_seen + self.timeout)
375
256
 
376
257
 
377
258
def peer_certificate(session):
378
 
    "Return the peer's OpenPGP certificate as a bytestring"
379
259
    # If not an OpenPGP certificate...
380
260
    if gnutls.library.functions.gnutls_certificate_type_get\
381
261
            (session._c_object) \
392
272
 
393
273
 
394
274
def fingerprint(openpgp):
395
 
    "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))
396
279
    # New GnuTLS "datum" with the OpenPGP public key
397
280
    datum = gnutls.library.types.gnutls_datum_t\
398
281
        (ctypes.cast(ctypes.c_char_p(openpgp),
399
282
                     ctypes.POINTER(ctypes.c_ubyte)),
400
283
         ctypes.c_uint(len(openpgp)))
401
 
    # New empty GnuTLS certificate
402
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
403
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
404
 
        (ctypes.byref(crt))
405
284
    # Import the OpenPGP public key into the certificate
406
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
407
 
                    (crt, ctypes.byref(datum),
408
 
                     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)
409
289
    # New buffer for the fingerprint
410
290
    buffer = ctypes.create_string_buffer(20)
411
291
    buffer_length = ctypes.c_size_t()
427
307
    Note: This will run in its own forked process."""
428
308
    
429
309
    def handle(self):
430
 
        logger.info(u"TCP connection from: %s",
 
310
        logger.debug(u"TCP connection from: %s",
431
311
                     unicode(self.client_address))
432
 
        session = gnutls.connection.ClientSession\
433
 
                  (self.request, gnutls.connection.X509Credentials())
434
 
        
435
 
        line = self.request.makefile().readline()
436
 
        logger.debug(u"Protocol version: %r", line)
437
 
        try:
438
 
            if int(line.strip().split()[0]) > 1:
439
 
                raise RuntimeError
440
 
        except (ValueError, IndexError, RuntimeError), error:
441
 
            logger.error(u"Unknown protocol version: %s", error)
442
 
            return
443
 
        
444
 
        # Note: gnutls.connection.X509Credentials is really a generic
445
 
        # GnuTLS certificate credentials object so long as no X.509
446
 
        # keys are added to it.  Therefore, we can use it here despite
447
 
        # using OpenPGP certificates.
 
312
        session = gnutls.connection.ClientSession(self.request,
 
313
                                                  gnutls.connection.\
 
314
                                                  X509Credentials())
448
315
        
449
316
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
450
317
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
451
318
        #                "+DHE-DSS"))
452
 
        priority = "NORMAL"             # Fallback default, since this
453
 
                                        # MUST be set.
454
 
        if self.server.settings["priority"]:
455
 
            priority = self.server.settings["priority"]
 
319
        priority = "SECURE256"
 
320
        
456
321
        gnutls.library.functions.gnutls_priority_set_direct\
457
322
            (session._c_object, priority, None);
458
323
        
459
324
        try:
460
325
            session.handshake()
461
326
        except gnutls.errors.GNUTLSError, error:
462
 
            logger.warning(u"Handshake failed: %s", error)
 
327
            logger.debug(u"Handshake failed: %s", error)
463
328
            # Do not run session.bye() here: the session is not
464
329
            # established.  Just abandon the request.
465
330
            return
466
331
        try:
467
332
            fpr = fingerprint(peer_certificate(session))
468
333
        except (TypeError, gnutls.errors.GNUTLSError), error:
469
 
            logger.warning(u"Bad certificate: %s", error)
 
334
            logger.debug(u"Bad certificate: %s", error)
470
335
            session.bye()
471
336
            return
472
337
        logger.debug(u"Fingerprint: %s", fpr)
473
338
        client = None
474
 
        for c in self.server.clients:
 
339
        for c in clients:
475
340
            if c.fingerprint == fpr:
476
341
                client = c
477
342
                break
478
 
        if not client:
479
 
            logger.warning(u"Client not found for fingerprint: %s",
480
 
                           fpr)
481
 
            session.bye()
482
 
            return
483
343
        # Have to check if client.still_valid(), since it is possible
484
344
        # that the client timed out while establishing the GnuTLS
485
345
        # session.
486
 
        if not client.still_valid():
487
 
            logger.warning(u"Client %(name)s is invalid",
488
 
                           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)
489
353
            session.bye()
490
354
            return
491
355
        sent_size = 0
501
365
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
502
366
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
503
367
    Attributes:
504
 
        settings:       Server settings
 
368
        options:        Command line options
505
369
        clients:        Set() of Client objects
506
370
    """
507
371
    address_family = socket.AF_INET6
508
372
    def __init__(self, *args, **kwargs):
509
 
        if "settings" in kwargs:
510
 
            self.settings = kwargs["settings"]
511
 
            del kwargs["settings"]
 
373
        if "options" in kwargs:
 
374
            self.options = kwargs["options"]
 
375
            del kwargs["options"]
512
376
        if "clients" in kwargs:
513
377
            self.clients = kwargs["clients"]
514
378
            del kwargs["clients"]
517
381
        """This overrides the normal server_bind() function
518
382
        to bind to an interface if one was specified, and also NOT to
519
383
        bind to an address or port if they were not specified."""
520
 
        if self.settings["interface"]:
521
 
            # 25 is from /usr/include/asm-i486/socket.h
522
 
            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
523
388
            try:
524
389
                self.socket.setsockopt(socket.SOL_SOCKET,
525
 
                                       SO_BINDTODEVICE,
526
 
                                       self.settings["interface"])
 
390
                                       socket.SO_BINDTODEVICE,
 
391
                                       self.options.interface)
527
392
            except socket.error, error:
528
393
                if error[0] == errno.EPERM:
529
 
                    logger.error(u"No permission to"
530
 
                                 u" bind to interface %s",
531
 
                                 self.settings["interface"])
 
394
                    logger.warning(u"No permission to"
 
395
                                   u" bind to interface %s",
 
396
                                   self.options.interface)
532
397
                else:
533
398
                    raise error
534
399
        # Only bind(2) the socket if we really need to.
537
402
                in6addr_any = "::"
538
403
                self.server_address = (in6addr_any,
539
404
                                       self.server_address[1])
540
 
            elif not self.server_address[1]:
 
405
            elif self.server_address[1] is None:
541
406
                self.server_address = (self.server_address[0],
542
407
                                       0)
543
 
#                 if self.settings["interface"]:
544
 
#                     self.server_address = (self.server_address[0],
545
 
#                                            0, # port
546
 
#                                            0, # flowinfo
547
 
#                                            if_nametoindex
548
 
#                                            (self.settings
549
 
#                                             ["interface"]))
550
408
            return super(type(self), self).server_bind()
551
409
 
552
410
 
584
442
    return delta
585
443
 
586
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
 
587
478
def server_state_changed(state):
588
 
    """Derived from the Avahi example code"""
 
479
    """From the Avahi server example code"""
589
480
    if state == avahi.SERVER_COLLISION:
590
 
        logger.error(u"Server name collision")
591
 
        service.remove()
 
481
        logger.warning(u"Server name collision")
 
482
        remove_service()
592
483
    elif state == avahi.SERVER_RUNNING:
593
 
        service.add()
 
484
        add_service()
594
485
 
595
486
 
596
487
def entry_group_state_changed(state, error):
597
 
    """Derived from the Avahi example code"""
 
488
    """From the Avahi server example code"""
 
489
    global serviceName, server, rename_count
 
490
    
598
491
    logger.debug(u"state change: %i", state)
599
492
    
600
493
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
601
494
        logger.debug(u"Service established.")
602
495
    elif state == avahi.ENTRY_GROUP_COLLISION:
603
 
        logger.warning(u"Service name collision.")
604
 
        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()
605
510
    elif state == avahi.ENTRY_GROUP_FAILURE:
606
 
        logger.critical(u"Error in group state changed %s",
607
 
                        unicode(error))
608
 
        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
 
609
516
 
610
517
def if_nametoindex(interface):
611
 
    """Call the C function if_nametoindex(), or equivalent"""
612
 
    global if_nametoindex
 
518
    """Call the C function if_nametoindex()"""
613
519
    try:
614
 
        if "ctypes.util" not in sys.modules:
615
 
            import ctypes.util
616
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
617
 
            (ctypes.util.find_library("c")).if_nametoindex
 
520
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
 
521
        return libc.if_nametoindex(interface)
618
522
    except (OSError, AttributeError):
619
523
        if "struct" not in sys.modules:
620
524
            import struct
621
525
        if "fcntl" not in sys.modules:
622
526
            import fcntl
623
 
        def if_nametoindex(interface):
624
 
            "Get an interface index the hard way, i.e. using fcntl()"
625
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
626
 
            s = socket.socket()
627
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
628
 
                                struct.pack("16s16x", interface))
629
 
            s.close()
630
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
631
 
            return interface_index
632
 
    return if_nametoindex(interface)
633
 
 
634
 
 
635
 
def daemon(nochdir = False, noclose = False):
636
 
    """See daemon(3).  Standard BSD Unix function.
637
 
    This should really exist as os.daemon, but it doesn't (yet)."""
638
 
    if os.fork():
639
 
        sys.exit()
640
 
    os.setsid()
641
 
    if not nochdir:
642
 
        os.chdir("/")
643
 
    if os.fork():
644
 
        sys.exit()
645
 
    if not noclose:
646
 
        # Close all standard open file descriptors
647
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
648
 
        if not stat.S_ISCHR(os.fstat(null).st_mode):
649
 
            raise OSError(errno.ENODEV,
650
 
                          "/dev/null not a character device")
651
 
        os.dup2(null, sys.stdin.fileno())
652
 
        os.dup2(null, sys.stdout.fileno())
653
 
        os.dup2(null, sys.stderr.fileno())
654
 
        if null > 2:
655
 
            os.close(null)
656
 
 
657
 
 
658
 
def main():
659
 
    global main_loop_started
660
 
    main_loop_started = False
661
 
    
662
 
    parser = OptionParser(version = "%%prog %s" % version)
 
527
        SIOCGIFINDEX = 0x8933      # From /usr/include/linux/sockios.h
 
528
        s = socket.socket()
 
529
        ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
 
530
                            struct.pack("16s16x", interface))
 
531
        s.close()
 
532
        interface_index = struct.unpack("I", ifreq[16:20])[0]
 
533
        return interface_index
 
534
 
 
535
 
 
536
if __name__ == '__main__':
 
537
    parser = OptionParser()
663
538
    parser.add_option("-i", "--interface", type="string",
664
 
                      metavar="IF", help="Bind to interface IF")
665
 
    parser.add_option("-a", "--address", type="string",
666
 
                      help="Address to listen for requests on")
667
 
    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,
668
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")
669
561
    parser.add_option("--check", action="store_true", default=False,
670
562
                      help="Run self-test")
671
 
    parser.add_option("--debug", action="store_true",
672
 
                      help="Debug mode; run in foreground and log to"
673
 
                      " terminal")
674
 
    parser.add_option("--priority", type="string", help="GnuTLS"
675
 
                      " priority string (see GnuTLS documentation)")
676
 
    parser.add_option("--servicename", type="string", metavar="NAME",
677
 
                      help="Zeroconf service name")
678
 
    parser.add_option("--configdir", type="string",
679
 
                      default="/etc/mandos", metavar="DIR",
680
 
                      help="Directory to search for configuration"
681
 
                      " files")
 
563
    parser.add_option("--debug", action="store_true", default=False,
 
564
                      help="Debug mode")
682
565
    (options, args) = parser.parse_args()
683
566
    
684
567
    if options.check:
686
569
        doctest.testmod()
687
570
        sys.exit()
688
571
    
689
 
    # Default values for config file for server-global settings
690
 
    server_defaults = { "interface": "",
691
 
                        "address": "",
692
 
                        "port": "",
693
 
                        "debug": "False",
694
 
                        "priority":
695
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
696
 
                        "servicename": "Mandos",
697
 
                        }
698
 
    
699
 
    # Parse config file for server-global settings
700
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
701
 
    del server_defaults
702
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
703
 
    server_section = "server"
704
 
    # Convert the SafeConfigParser object to a dict
705
 
    server_settings = dict(server_config.items(server_section))
706
 
    # Use getboolean on the boolean config option
707
 
    server_settings["debug"] = server_config.getboolean\
708
 
                               (server_section, "debug")
709
 
    del server_config
710
 
    
711
 
    # Override the settings from the config file with command line
712
 
    # options, if set.
713
 
    for option in ("interface", "address", "port", "debug",
714
 
                   "priority", "servicename", "configdir"):
715
 
        value = getattr(options, option)
716
 
        if value is not None:
717
 
            server_settings[option] = value
718
 
    del options
719
 
    # Now we have our good server settings in "server_settings"
720
 
    
721
 
    debug = server_settings["debug"]
722
 
    
723
 
    if not debug:
724
 
        syslogger.setLevel(logging.WARNING)
725
 
        console.setLevel(logging.WARNING)
726
 
    
727
 
    if server_settings["servicename"] != "Mandos":
728
 
        syslogger.setFormatter(logging.Formatter\
729
 
                               ('Mandos (%s): %%(levelname)s:'
730
 
                                ' %%(message)s'
731
 
                                % server_settings["servicename"]))
732
 
    
733
 
    # Parse config file with clients
734
 
    client_defaults = { "timeout": "1h",
735
 
                        "interval": "5m",
736
 
                        "checker": "fping -q -- %%(host)s",
737
 
                        }
738
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
739
 
    client_config.read(os.path.join(server_settings["configdir"],
740
 
                                    "clients.conf"))
741
 
    
742
 
    global service
743
 
    service = AvahiService(name = server_settings["servicename"],
744
 
                           type = "_mandos._tcp", );
745
 
    if server_settings["interface"]:
746
 
        service.interface = if_nametoindex(server_settings["interface"])
747
 
    
748
 
    global main_loop
749
 
    global bus
750
 
    global server
751
 
    # 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
752
589
    DBusGMainLoop(set_as_default=True )
753
590
    main_loop = gobject.MainLoop()
754
591
    bus = dbus.SystemBus()
757
594
            avahi.DBUS_INTERFACE_SERVER )
758
595
    # End of Avahi example code
759
596
    
 
597
    debug = options.debug
 
598
    
760
599
    clients = Set()
761
600
    def remove_from_clients(client):
762
601
        clients.remove(client)
763
602
        if not clients:
764
 
            logger.critical(u"No clients left, exiting")
765
 
            sys.exit()
 
603
            logger.debug(u"No clients left, exiting")
 
604
            main_loop.quit()
766
605
    
767
 
    clients.update(Set(Client(name = section,
 
606
    clients.update(Set(Client(name=section, options=options,
768
607
                              stop_hook = remove_from_clients,
769
 
                              config
770
 
                              = dict(client_config.items(section)))
 
608
                              **(dict(client_config\
 
609
                                      .items(section))))
771
610
                       for section in client_config.sections()))
772
 
    if not clients:
773
 
        logger.critical(u"No clients defined")
774
 
        sys.exit(1)
775
 
    
776
 
    if not debug:
777
 
        logger.removeHandler(console)
778
 
        daemon()
779
 
    
780
 
    pidfilename = "/var/run/mandos/mandos.pid"
781
 
    pid = os.getpid()
782
 
    try:
783
 
        pidfile = open(pidfilename, "w")
784
 
        pidfile.write(str(pid) + "\n")
785
 
        pidfile.close()
786
 
        del pidfile
787
 
    except IOError, err:
788
 
        logger.error(u"Could not write %s file with PID %d",
789
 
                     pidfilename, os.getpid())
790
 
    
791
 
    def cleanup():
792
 
        "Cleanup function; run on exit"
793
 
        global group
794
 
        # From the Avahi example code
795
 
        if not group is None:
796
 
            group.Free()
797
 
            group = None
798
 
        # End of Avahi example code
799
 
        
800
 
        while clients:
801
 
            client = clients.pop()
802
 
            client.stop_hook = None
803
 
            client.stop()
804
 
    
805
 
    atexit.register(cleanup)
806
 
    
807
 
    if not debug:
808
 
        signal.signal(signal.SIGINT, signal.SIG_IGN)
809
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
810
 
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
811
 
    
812
611
    for client in clients:
813
612
        client.start()
814
613
    
815
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
816
 
                                 server_settings["port"]),
 
614
    tcp_server = IPv6_TCPServer((None, options.port),
817
615
                                tcp_handler,
818
 
                                settings=server_settings,
 
616
                                options=options,
819
617
                                clients=clients)
820
 
    # Find out what port we got
821
 
    service.port = tcp_server.socket.getsockname()[1]
822
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
823
 
                u" scope_id %d" % tcp_server.socket.getsockname())
824
 
    
825
 
    #service.interface = tcp_server.socket.getsockname()[3]
826
 
    
 
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)
827
634
    try:
828
 
        # From the Avahi example code
829
 
        server.connect_to_signal("StateChanged", server_state_changed)
830
 
        try:
831
 
            server_state_changed(server.GetState())
832
 
        except dbus.exceptions.DBusException, error:
833
 
            logger.critical(u"DBusException: %s", error)
834
 
            sys.exit(1)
835
 
        # End of Avahi example code
836
 
        
837
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
838
 
                             lambda *args, **kwargs:
839
 
                             tcp_server.handle_request\
840
 
                             (*args[2:], **kwargs) or True)
841
 
        
842
 
        logger.debug(u"Starting main loop")
843
 
        main_loop_started = True
844
635
        main_loop.run()
845
 
    except AvahiError, error:
846
 
        logger.critical(u"AvahiError: %s" + unicode(error))
847
 
        sys.exit(1)
848
636
    except KeyboardInterrupt:
849
 
        if debug:
850
 
            print
 
637
        print
 
638
    
 
639
    # Cleanup here
851
640
 
852
 
if __name__ == '__main__':
853
 
    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()