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  • Committer: Björn Påhlsson
  • Date: 2008-07-20 22:58:26 UTC
  • mto: This revision was merged to the branch mainline in revision 17.
  • Revision ID: belorn@braxen-20080720225826-cj2n2s0xbmxmra60
Added debugg support in form off --debug and --debug=mandosclient

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#!/usr/bin/python
2
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
28
 
# <http://www.gnu.org/licenses/>.
29
 
30
 
# Contact the authors at <mandos@fukt.bsnet.se>.
31
 
32
3
 
33
4
from __future__ import division
34
5
 
53
24
import subprocess
54
25
import atexit
55
26
import stat
56
 
import logging
57
 
import logging.handlers
58
27
 
59
28
import dbus
60
29
import gobject
62
31
from dbus.mainloop.glib import DBusGMainLoop
63
32
import ctypes
64
33
 
65
 
version = "1.0"
 
34
import logging
 
35
import logging.handlers
66
36
 
67
37
logger = logging.Logger('mandos')
68
38
syslogger = logging.handlers.SysLogHandler\
69
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
70
 
             address = "/dev/log")
 
39
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON)
71
40
syslogger.setFormatter(logging.Formatter\
72
 
                        ('Mandos: %(levelname)s: %(message)s'))
 
41
                        ('%(levelname)s: %(message)s'))
73
42
logger.addHandler(syslogger)
74
 
 
75
 
console = logging.StreamHandler()
76
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
77
 
                                       ' %(message)s'))
78
 
logger.addHandler(console)
79
 
 
80
 
class AvahiError(Exception):
81
 
    def __init__(self, value):
82
 
        self.value = value
83
 
    def __str__(self):
84
 
        return repr(self.value)
85
 
 
86
 
class AvahiServiceError(AvahiError):
87
 
    pass
88
 
 
89
 
class AvahiGroupError(AvahiError):
90
 
    pass
91
 
 
92
 
 
93
 
class AvahiService(object):
94
 
    """An Avahi (Zeroconf) service.
95
 
    Attributes:
96
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
97
 
               Used to optionally bind to the specified interface.
98
 
    name: string; Example: 'Mandos'
99
 
    type: string; Example: '_mandos._tcp'.
100
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
101
 
    port: integer; what port to announce
102
 
    TXT: list of strings; TXT record for the service
103
 
    domain: string; Domain to publish on, default to .local if empty.
104
 
    host: string; Host to publish records for, default is localhost
105
 
    max_renames: integer; maximum number of renames
106
 
    rename_count: integer; counter so we only rename after collisions
107
 
                  a sensible number of times
108
 
    """
109
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
110
 
                 type = None, port = None, TXT = None, domain = "",
111
 
                 host = "", max_renames = 32768):
112
 
        self.interface = interface
113
 
        self.name = name
114
 
        self.type = type
115
 
        self.port = port
116
 
        if TXT is None:
117
 
            self.TXT = []
118
 
        else:
119
 
            self.TXT = TXT
120
 
        self.domain = domain
121
 
        self.host = host
122
 
        self.rename_count = 0
123
 
        self.max_renames = max_renames
124
 
    def rename(self):
125
 
        """Derived from the Avahi example code"""
126
 
        if self.rename_count >= self.max_renames:
127
 
            logger.critical(u"No suitable Zeroconf service name found"
128
 
                            u" after %i retries, exiting.",
129
 
                            rename_count)
130
 
            raise AvahiServiceError("Too many renames")
131
 
        self.name = server.GetAlternativeServiceName(self.name)
132
 
        logger.info(u"Changing Zeroconf service name to %r ...",
133
 
                    str(self.name))
134
 
        syslogger.setFormatter(logging.Formatter\
135
 
                               ('Mandos (%s): %%(levelname)s:'
136
 
                               ' %%(message)s' % self.name))
137
 
        self.remove()
138
 
        self.add()
139
 
        self.rename_count += 1
140
 
    def remove(self):
141
 
        """Derived from the Avahi example code"""
142
 
        if group is not None:
143
 
            group.Reset()
144
 
    def add(self):
145
 
        """Derived from the Avahi example code"""
146
 
        global group
147
 
        if group is None:
148
 
            group = dbus.Interface\
149
 
                    (bus.get_object(avahi.DBUS_NAME,
150
 
                                    server.EntryGroupNew()),
151
 
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
152
 
            group.connect_to_signal('StateChanged',
153
 
                                    entry_group_state_changed)
154
 
        logger.debug(u"Adding Zeroconf service '%s' of type '%s' ...",
155
 
                     service.name, service.type)
156
 
        group.AddService(
157
 
                self.interface,         # interface
158
 
                avahi.PROTO_INET6,      # protocol
159
 
                dbus.UInt32(0),         # flags
160
 
                self.name, self.type,
161
 
                self.domain, self.host,
162
 
                dbus.UInt16(self.port),
163
 
                avahi.string_array_to_txt_array(self.TXT))
164
 
        group.Commit()
165
 
 
166
 
# From the Avahi example code:
167
 
group = None                            # our entry group
 
43
del syslogger
 
44
 
 
45
# This variable is used to optionally bind to a specified interface.
 
46
# It is a global variable to fit in with the other variables from the
 
47
# Avahi server example code.
 
48
serviceInterface = avahi.IF_UNSPEC
 
49
# From the Avahi server example code:
 
50
serviceName = "Mandos"
 
51
serviceType = "_mandos._tcp" # http://www.dns-sd.org/ServiceTypes.html
 
52
servicePort = None                      # Not known at startup
 
53
serviceTXT = []                         # TXT record for the service
 
54
domain = ""                  # Domain to publish on, default to .local
 
55
host = ""          # Host to publish records for, default to localhost
 
56
group = None #our entry group
 
57
rename_count = 12       # Counter so we only rename after collisions a
 
58
                        # sensible number of times
168
59
# End of Avahi example code
169
60
 
170
61
 
175
66
    fingerprint: string (40 or 32 hexadecimal digits); used to
176
67
                 uniquely identify the client
177
68
    secret:    bytestring; sent verbatim (over TLS) to client
178
 
    host:      string; available for use by the checker command
179
 
    created:   datetime.datetime(); object creation, not client host
180
 
    last_checked_ok: datetime.datetime() or None if not yet checked OK
181
 
    timeout:   datetime.timedelta(); How long from last_checked_ok
182
 
                                     until this client is invalid
 
69
    fqdn:      string (FQDN); available for use by the checker command
 
70
    created:   datetime.datetime()
 
71
    last_seen: datetime.datetime() or None if not yet seen
 
72
    timeout:   datetime.timedelta(); How long from last_seen until
 
73
                                     this client is invalid
183
74
    interval:  datetime.timedelta(); How often to start a new checker
184
75
    stop_hook: If set, called by stop() as stop_hook(self)
185
76
    checker:   subprocess.Popen(); a running checker process used
186
77
                                   to see if the client lives.
187
 
                                   'None' if no process is running.
 
78
                                   Is None if no process is running.
188
79
    checker_initiator_tag: a gobject event source tag, or None
189
80
    stop_initiator_tag:    - '' -
190
81
    checker_callback_tag:  - '' -
191
82
    checker_command: string; External command which is run to check if
192
 
                     client lives.  %() expansions are done at
 
83
                     client lives.  %()s expansions are done at
193
84
                     runtime with vars(self) as dict, so that for
194
85
                     instance %(name)s can be used in the command.
195
86
    Private attibutes:
196
87
    _timeout: Real variable for 'timeout'
197
88
    _interval: Real variable for 'interval'
198
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
 
89
    _timeout_milliseconds: Used by gobject.timeout_add()
199
90
    _interval_milliseconds: - '' -
200
91
    """
201
92
    def _set_timeout(self, timeout):
221
112
    interval = property(lambda self: self._interval,
222
113
                        _set_interval)
223
114
    del _set_interval
224
 
    def __init__(self, name = None, stop_hook=None, config={}):
225
 
        """Note: the 'checker' key in 'config' sets the
226
 
        'checker_command' attribute and *not* the 'checker'
227
 
        attribute."""
 
115
    def __init__(self, name=None, options=None, stop_hook=None,
 
116
                 fingerprint=None, secret=None, secfile=None,
 
117
                 fqdn=None, timeout=None, interval=-1, checker=None):
228
118
        self.name = name
229
 
        logger.debug(u"Creating client %r", self.name)
230
 
        # Uppercase and remove spaces from fingerprint for later
231
 
        # comparison purposes with return value from the fingerprint()
232
 
        # function
233
 
        self.fingerprint = config["fingerprint"].upper()\
234
 
                           .replace(u" ", u"")
235
 
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
236
 
        if "secret" in config:
237
 
            self.secret = config["secret"].decode(u"base64")
238
 
        elif "secfile" in config:
239
 
            sf = open(config["secfile"])
 
119
        # Uppercase and remove spaces from fingerprint
 
120
        # for later comparison purposes with return value of
 
121
        # the fingerprint() function
 
122
        self.fingerprint = fingerprint.upper().replace(u" ", u"")
 
123
        if secret:
 
124
            self.secret = secret.decode(u"base64")
 
125
        elif secfile:
 
126
            sf = open(secfile)
240
127
            self.secret = sf.read()
241
128
            sf.close()
242
129
        else:
243
 
            raise TypeError(u"No secret or secfile for client %s"
244
 
                            % self.name)
245
 
        self.host = config.get("host", "")
 
130
            raise RuntimeError(u"No secret or secfile for client %s"
 
131
                               % self.name)
 
132
        self.fqdn = fqdn                # string
246
133
        self.created = datetime.datetime.now()
247
 
        self.last_checked_ok = None
248
 
        self.timeout = string_to_delta(config["timeout"])
249
 
        self.interval = string_to_delta(config["interval"])
 
134
        self.last_seen = None
 
135
        if timeout is None:
 
136
            self.timeout = options.timeout
 
137
        else:
 
138
            self.timeout = string_to_delta(timeout)
 
139
        if interval == -1:
 
140
            self.interval = options.interval
 
141
        else:
 
142
            self.interval = string_to_delta(interval)
250
143
        self.stop_hook = stop_hook
251
144
        self.checker = None
252
145
        self.checker_initiator_tag = None
253
146
        self.stop_initiator_tag = None
254
147
        self.checker_callback_tag = None
255
 
        self.check_command = config["checker"]
 
148
        self.check_command = checker
256
149
    def start(self):
257
 
        """Start this client's checker and timeout hooks"""
 
150
        """Start this clients checker and timeout hooks"""
258
151
        # Schedule a new checker to be started an 'interval' from now,
259
152
        # and every interval from then on.
260
153
        self.checker_initiator_tag = gobject.timeout_add\
268
161
                                   self.stop)
269
162
    def stop(self):
270
163
        """Stop this client.
271
 
        The possibility that a client might be restarted is left open,
272
 
        but not currently used."""
273
 
        # If this client doesn't have a secret, it is already stopped.
274
 
        if hasattr(self, "secret") and self.secret:
275
 
            logger.info(u"Stopping client %s", self.name)
276
 
            self.secret = None
277
 
        else:
278
 
            return False
279
 
        if getattr(self, "stop_initiator_tag", False):
 
164
        The possibility that this client might be restarted is left
 
165
        open, but not currently used."""
 
166
        logger.debug(u"Stopping client %s", self.name)
 
167
        self.secret = None
 
168
        if self.stop_initiator_tag:
280
169
            gobject.source_remove(self.stop_initiator_tag)
281
170
            self.stop_initiator_tag = None
282
 
        if getattr(self, "checker_initiator_tag", False):
 
171
        if self.checker_initiator_tag:
283
172
            gobject.source_remove(self.checker_initiator_tag)
284
173
            self.checker_initiator_tag = None
285
174
        self.stop_checker()
288
177
        # Do not run this again if called by a gobject.timeout_add
289
178
        return False
290
179
    def __del__(self):
291
 
        self.stop_hook = None
292
 
        self.stop()
 
180
        # Some code duplication here and in stop()
 
181
        if hasattr(self, "stop_initiator_tag") \
 
182
               and self.stop_initiator_tag:
 
183
            gobject.source_remove(self.stop_initiator_tag)
 
184
            self.stop_initiator_tag = None
 
185
        if hasattr(self, "checker_initiator_tag") \
 
186
               and self.checker_initiator_tag:
 
187
            gobject.source_remove(self.checker_initiator_tag)
 
188
            self.checker_initiator_tag = None
 
189
        self.stop_checker()
293
190
    def checker_callback(self, pid, condition):
294
191
        """The checker has completed, so take appropriate actions."""
295
192
        now = datetime.datetime.now()
296
 
        self.checker_callback_tag = None
297
 
        self.checker = None
298
193
        if os.WIFEXITED(condition) \
299
194
               and (os.WEXITSTATUS(condition) == 0):
300
 
            logger.info(u"Checker for %(name)s succeeded",
301
 
                        vars(self))
302
 
            self.last_checked_ok = now
 
195
            logger.debug(u"Checker for %(name)s succeeded",
 
196
                         vars(self))
 
197
            self.last_seen = now
303
198
            gobject.source_remove(self.stop_initiator_tag)
304
199
            self.stop_initiator_tag = gobject.timeout_add\
305
200
                                      (self._timeout_milliseconds,
308
203
            logger.warning(u"Checker for %(name)s crashed?",
309
204
                           vars(self))
310
205
        else:
311
 
            logger.info(u"Checker for %(name)s failed",
312
 
                        vars(self))
 
206
            logger.debug(u"Checker for %(name)s failed",
 
207
                         vars(self))
 
208
            self.checker = None
 
209
        self.checker_callback_tag = None
313
210
    def start_checker(self):
314
211
        """Start a new checker subprocess if one is not running.
315
212
        If a checker already exists, leave it running and do
316
213
        nothing."""
317
 
        # The reason for not killing a running checker is that if we
318
 
        # did that, then if a checker (for some reason) started
319
 
        # running slowly and taking more than 'interval' time, the
320
 
        # client would inevitably timeout, since no checker would get
321
 
        # a chance to run to completion.  If we instead leave running
322
 
        # checkers alone, the checker would have to take more time
323
 
        # than 'timeout' for the client to be declared invalid, which
324
 
        # is as it should be.
325
214
        if self.checker is None:
326
215
            try:
327
 
                # In case check_command has exactly one % operator
328
 
                command = self.check_command % self.host
 
216
                command = self.check_command % self.fqdn
329
217
            except TypeError:
330
 
                # Escape attributes for the shell
331
218
                escaped_attrs = dict((key, re.escape(str(val)))
332
219
                                     for key, val in
333
220
                                     vars(self).iteritems())
334
221
                try:
335
222
                    command = self.check_command % escaped_attrs
336
223
                except TypeError, error:
337
 
                    logger.error(u'Could not format string "%s":'
338
 
                                 u' %s', self.check_command, error)
 
224
                    logger.critical(u'Could not format string "%s":'
 
225
                                    u' %s', self.check_command, error)
339
226
                    return True # Try again later
340
227
            try:
341
 
                logger.info(u"Starting checker %r for %s",
342
 
                            command, self.name)
343
 
                # We don't need to redirect stdout and stderr, since
344
 
                # in normal mode, that is already done by daemon(),
345
 
                # and in debug mode we don't want to.  (Stdin is
346
 
                # always replaced by /dev/null.)
347
 
                self.checker = subprocess.Popen(command,
348
 
                                                close_fds=True,
349
 
                                                shell=True, cwd="/")
 
228
                logger.debug(u"Starting checker %r for %s",
 
229
                             command, self.name)
 
230
                self.checker = subprocess.\
 
231
                               Popen(command,
 
232
                                     close_fds=True, shell=True,
 
233
                                     cwd="/")
350
234
                self.checker_callback_tag = gobject.child_watch_add\
351
235
                                            (self.checker.pid,
352
236
                                             self.checker_callback)
353
 
            except OSError, error:
 
237
            except subprocess.OSError, error:
354
238
                logger.error(u"Failed to start subprocess: %s",
355
239
                             error)
356
240
        # Re-run this periodically if run by gobject.timeout_add
357
241
        return True
358
242
    def stop_checker(self):
359
243
        """Force the checker process, if any, to stop."""
360
 
        if self.checker_callback_tag:
361
 
            gobject.source_remove(self.checker_callback_tag)
362
 
            self.checker_callback_tag = None
363
 
        if getattr(self, "checker", None) is None:
 
244
        if not hasattr(self, "checker") or self.checker is None:
364
245
            return
365
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
366
 
        try:
367
 
            os.kill(self.checker.pid, signal.SIGTERM)
368
 
            #os.sleep(0.5)
369
 
            #if self.checker.poll() is None:
370
 
            #    os.kill(self.checker.pid, signal.SIGKILL)
371
 
        except OSError, error:
372
 
            if error.errno != errno.ESRCH: # No such process
373
 
                raise
 
246
        gobject.source_remove(self.checker_callback_tag)
 
247
        self.checker_callback_tag = None
 
248
        os.kill(self.checker.pid, signal.SIGTERM)
 
249
        if self.checker.poll() is None:
 
250
            os.kill(self.checker.pid, signal.SIGKILL)
374
251
        self.checker = None
375
 
    def still_valid(self):
 
252
    def still_valid(self, now=None):
376
253
        """Has the timeout not yet passed for this client?"""
377
 
        now = datetime.datetime.now()
378
 
        if self.last_checked_ok is None:
 
254
        if now is None:
 
255
            now = datetime.datetime.now()
 
256
        if self.last_seen is None:
379
257
            return now < (self.created + self.timeout)
380
258
        else:
381
 
            return now < (self.last_checked_ok + self.timeout)
 
259
            return now < (self.last_seen + self.timeout)
382
260
 
383
261
 
384
262
def peer_certificate(session):
385
 
    "Return the peer's OpenPGP certificate as a bytestring"
 
263
    "Return an OpenPGP data packet string for the peer's certificate"
386
264
    # If not an OpenPGP certificate...
387
265
    if gnutls.library.functions.gnutls_certificate_type_get\
388
266
            (session._c_object) \
399
277
 
400
278
 
401
279
def fingerprint(openpgp):
402
 
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
 
280
    "Convert an OpenPGP data string to a hexdigit fingerprint string"
 
281
    # New empty GnuTLS certificate
 
282
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
283
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
284
        (ctypes.byref(crt))
403
285
    # New GnuTLS "datum" with the OpenPGP public key
404
286
    datum = gnutls.library.types.gnutls_datum_t\
405
287
        (ctypes.cast(ctypes.c_char_p(openpgp),
406
288
                     ctypes.POINTER(ctypes.c_ubyte)),
407
289
         ctypes.c_uint(len(openpgp)))
408
 
    # New empty GnuTLS certificate
409
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
410
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
411
 
        (ctypes.byref(crt))
412
290
    # Import the OpenPGP public key into the certificate
413
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
414
 
                    (crt, ctypes.byref(datum),
415
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
416
 
    # Verify the self signature in the key
417
 
    crtverify = ctypes.c_uint();
418
 
    gnutls.library.functions.gnutls_openpgp_crt_verify_self\
419
 
        (crt, 0, ctypes.byref(crtverify))
420
 
    if crtverify.value != 0:
421
 
        gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
422
 
        raise gnutls.errors.CertificateSecurityError("Verify failed")
 
291
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
 
292
        (crt,
 
293
         ctypes.byref(datum),
 
294
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
423
295
    # New buffer for the fingerprint
424
296
    buffer = ctypes.create_string_buffer(20)
425
297
    buffer_length = ctypes.c_size_t()
441
313
    Note: This will run in its own forked process."""
442
314
    
443
315
    def handle(self):
444
 
        logger.info(u"TCP connection from: %s",
 
316
        logger.debug(u"TCP connection from: %s",
445
317
                     unicode(self.client_address))
446
 
        session = gnutls.connection.ClientSession\
447
 
                  (self.request, gnutls.connection.X509Credentials())
448
 
        
449
 
        line = self.request.makefile().readline()
450
 
        logger.debug(u"Protocol version: %r", line)
451
 
        try:
452
 
            if int(line.strip().split()[0]) > 1:
453
 
                raise RuntimeError
454
 
        except (ValueError, IndexError, RuntimeError), error:
455
 
            logger.error(u"Unknown protocol version: %s", error)
456
 
            return
457
 
        
458
 
        # Note: gnutls.connection.X509Credentials is really a generic
459
 
        # GnuTLS certificate credentials object so long as no X.509
460
 
        # keys are added to it.  Therefore, we can use it here despite
461
 
        # using OpenPGP certificates.
 
318
        session = gnutls.connection.ClientSession(self.request,
 
319
                                                  gnutls.connection.\
 
320
                                                  X509Credentials())
462
321
        
463
322
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
464
323
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
465
324
        #                "+DHE-DSS"))
466
 
        priority = "NORMAL"             # Fallback default, since this
467
 
                                        # MUST be set.
468
 
        if self.server.settings["priority"]:
469
 
            priority = self.server.settings["priority"]
 
325
        priority = "SECURE256"
 
326
        
470
327
        gnutls.library.functions.gnutls_priority_set_direct\
471
328
            (session._c_object, priority, None);
472
329
        
473
330
        try:
474
331
            session.handshake()
475
332
        except gnutls.errors.GNUTLSError, error:
476
 
            logger.warning(u"Handshake failed: %s", error)
 
333
            logger.debug(u"Handshake failed: %s", error)
477
334
            # Do not run session.bye() here: the session is not
478
335
            # established.  Just abandon the request.
479
336
            return
480
337
        try:
481
338
            fpr = fingerprint(peer_certificate(session))
482
339
        except (TypeError, gnutls.errors.GNUTLSError), error:
483
 
            logger.warning(u"Bad certificate: %s", error)
 
340
            logger.debug(u"Bad certificate: %s", error)
484
341
            session.bye()
485
342
            return
486
343
        logger.debug(u"Fingerprint: %s", fpr)
487
344
        client = None
488
 
        for c in self.server.clients:
 
345
        for c in clients:
489
346
            if c.fingerprint == fpr:
490
347
                client = c
491
348
                break
492
 
        if not client:
493
 
            logger.warning(u"Client not found for fingerprint: %s",
494
 
                           fpr)
495
 
            session.bye()
496
 
            return
497
349
        # Have to check if client.still_valid(), since it is possible
498
350
        # that the client timed out while establishing the GnuTLS
499
351
        # session.
500
 
        if not client.still_valid():
501
 
            logger.warning(u"Client %(name)s is invalid",
502
 
                           vars(client))
 
352
        if (not client) or (not client.still_valid()):
 
353
            if client:
 
354
                logger.debug(u"Client %(name)s is invalid",
 
355
                             vars(client))
 
356
            else:
 
357
                logger.debug(u"Client not found for fingerprint: %s",
 
358
                             fpr)
503
359
            session.bye()
504
360
            return
505
361
        sent_size = 0
515
371
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
516
372
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
517
373
    Attributes:
518
 
        settings:       Server settings
 
374
        options:        Command line options
519
375
        clients:        Set() of Client objects
520
376
    """
521
377
    address_family = socket.AF_INET6
522
378
    def __init__(self, *args, **kwargs):
523
 
        if "settings" in kwargs:
524
 
            self.settings = kwargs["settings"]
525
 
            del kwargs["settings"]
 
379
        if "options" in kwargs:
 
380
            self.options = kwargs["options"]
 
381
            del kwargs["options"]
526
382
        if "clients" in kwargs:
527
383
            self.clients = kwargs["clients"]
528
384
            del kwargs["clients"]
531
387
        """This overrides the normal server_bind() function
532
388
        to bind to an interface if one was specified, and also NOT to
533
389
        bind to an address or port if they were not specified."""
534
 
        if self.settings["interface"]:
535
 
            # 25 is from /usr/include/asm-i486/socket.h
536
 
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
 
390
        if self.options.interface:
 
391
            if not hasattr(socket, "SO_BINDTODEVICE"):
 
392
                # From /usr/include/asm-i486/socket.h
 
393
                socket.SO_BINDTODEVICE = 25
537
394
            try:
538
395
                self.socket.setsockopt(socket.SOL_SOCKET,
539
 
                                       SO_BINDTODEVICE,
540
 
                                       self.settings["interface"])
 
396
                                       socket.SO_BINDTODEVICE,
 
397
                                       self.options.interface)
541
398
            except socket.error, error:
542
399
                if error[0] == errno.EPERM:
543
 
                    logger.error(u"No permission to"
544
 
                                 u" bind to interface %s",
545
 
                                 self.settings["interface"])
 
400
                    logger.warning(u"No permission to"
 
401
                                   u" bind to interface %s",
 
402
                                   self.options.interface)
546
403
                else:
547
404
                    raise error
548
405
        # Only bind(2) the socket if we really need to.
551
408
                in6addr_any = "::"
552
409
                self.server_address = (in6addr_any,
553
410
                                       self.server_address[1])
554
 
            elif not self.server_address[1]:
 
411
            elif self.server_address[1] is None:
555
412
                self.server_address = (self.server_address[0],
556
413
                                       0)
557
 
#                 if self.settings["interface"]:
558
 
#                     self.server_address = (self.server_address[0],
559
 
#                                            0, # port
560
 
#                                            0, # flowinfo
561
 
#                                            if_nametoindex
562
 
#                                            (self.settings
563
 
#                                             ["interface"]))
564
414
            return super(type(self), self).server_bind()
565
415
 
566
416
 
577
427
    datetime.timedelta(1)
578
428
    >>> string_to_delta(u'1w')
579
429
    datetime.timedelta(7)
580
 
    >>> string_to_delta('5m 30s')
581
 
    datetime.timedelta(0, 330)
582
430
    """
583
 
    timevalue = datetime.timedelta(0)
584
 
    for s in interval.split():
585
 
        try:
586
 
            suffix=unicode(s[-1])
587
 
            value=int(s[:-1])
588
 
            if suffix == u"d":
589
 
                delta = datetime.timedelta(value)
590
 
            elif suffix == u"s":
591
 
                delta = datetime.timedelta(0, value)
592
 
            elif suffix == u"m":
593
 
                delta = datetime.timedelta(0, 0, 0, 0, value)
594
 
            elif suffix == u"h":
595
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, value)
596
 
            elif suffix == u"w":
597
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
598
 
            else:
599
 
                raise ValueError
600
 
        except (ValueError, IndexError):
 
431
    try:
 
432
        suffix=unicode(interval[-1])
 
433
        value=int(interval[:-1])
 
434
        if suffix == u"d":
 
435
            delta = datetime.timedelta(value)
 
436
        elif suffix == u"s":
 
437
            delta = datetime.timedelta(0, value)
 
438
        elif suffix == u"m":
 
439
            delta = datetime.timedelta(0, 0, 0, 0, value)
 
440
        elif suffix == u"h":
 
441
            delta = datetime.timedelta(0, 0, 0, 0, 0, value)
 
442
        elif suffix == u"w":
 
443
            delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
 
444
        else:
601
445
            raise ValueError
602
 
        timevalue += delta
603
 
    return timevalue
 
446
    except (ValueError, IndexError):
 
447
        raise ValueError
 
448
    return delta
 
449
 
 
450
 
 
451
def add_service():
 
452
    """From the Avahi server example code"""
 
453
    global group, serviceName, serviceType, servicePort, serviceTXT, \
 
454
           domain, host
 
455
    if group is None:
 
456
        group = dbus.Interface(
 
457
                bus.get_object( avahi.DBUS_NAME,
 
458
                                server.EntryGroupNew()),
 
459
                avahi.DBUS_INTERFACE_ENTRY_GROUP)
 
460
        group.connect_to_signal('StateChanged',
 
461
                                entry_group_state_changed)
 
462
    logger.debug(u"Adding service '%s' of type '%s' ...",
 
463
                 serviceName, serviceType)
 
464
    
 
465
    group.AddService(
 
466
            serviceInterface,           # interface
 
467
            avahi.PROTO_INET6,          # protocol
 
468
            dbus.UInt32(0),             # flags
 
469
            serviceName, serviceType,
 
470
            domain, host,
 
471
            dbus.UInt16(servicePort),
 
472
            avahi.string_array_to_txt_array(serviceTXT))
 
473
    group.Commit()
 
474
 
 
475
 
 
476
def remove_service():
 
477
    """From the Avahi server example code"""
 
478
    global group
 
479
    
 
480
    if not group is None:
 
481
        group.Reset()
604
482
 
605
483
 
606
484
def server_state_changed(state):
607
 
    """Derived from the Avahi example code"""
 
485
    """From the Avahi server example code"""
608
486
    if state == avahi.SERVER_COLLISION:
609
 
        logger.error(u"Zeroconf server name collision")
610
 
        service.remove()
 
487
        logger.warning(u"Server name collision")
 
488
        remove_service()
611
489
    elif state == avahi.SERVER_RUNNING:
612
 
        service.add()
 
490
        add_service()
613
491
 
614
492
 
615
493
def entry_group_state_changed(state, error):
616
 
    """Derived from the Avahi example code"""
617
 
    logger.debug(u"Avahi state change: %i", state)
 
494
    """From the Avahi server example code"""
 
495
    global serviceName, server, rename_count
 
496
    
 
497
    logger.debug(u"state change: %i", state)
618
498
    
619
499
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
620
 
        logger.debug(u"Zeroconf service established.")
 
500
        logger.debug(u"Service established.")
621
501
    elif state == avahi.ENTRY_GROUP_COLLISION:
622
 
        logger.warning(u"Zeroconf service name collision.")
623
 
        service.rename()
 
502
        
 
503
        rename_count = rename_count - 1
 
504
        if rename_count > 0:
 
505
            name = server.GetAlternativeServiceName(name)
 
506
            logger.warning(u"Service name collision, "
 
507
                           u"changing name to '%s' ...", name)
 
508
            remove_service()
 
509
            add_service()
 
510
            
 
511
        else:
 
512
            logger.error(u"No suitable service name found after %i"
 
513
                         u" retries, exiting.", n_rename)
 
514
            killme(1)
624
515
    elif state == avahi.ENTRY_GROUP_FAILURE:
625
 
        logger.critical(u"Avahi: Error in group state changed %s",
626
 
                        unicode(error))
627
 
        raise AvahiGroupError("State changed: %s", str(error))
 
516
        logger.error(u"Error in group state changed %s",
 
517
                     unicode(error))
 
518
        killme(1)
 
519
 
628
520
 
629
521
def if_nametoindex(interface):
630
 
    """Call the C function if_nametoindex(), or equivalent"""
631
 
    global if_nametoindex
 
522
    """Call the C function if_nametoindex()"""
632
523
    try:
633
 
        if "ctypes.util" not in sys.modules:
634
 
            import ctypes.util
635
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
636
 
            (ctypes.util.find_library("c")).if_nametoindex
 
524
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
 
525
        return libc.if_nametoindex(interface)
637
526
    except (OSError, AttributeError):
638
527
        if "struct" not in sys.modules:
639
528
            import struct
640
529
        if "fcntl" not in sys.modules:
641
530
            import fcntl
642
 
        def if_nametoindex(interface):
643
 
            "Get an interface index the hard way, i.e. using fcntl()"
644
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
645
 
            s = socket.socket()
646
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
647
 
                                struct.pack("16s16x", interface))
648
 
            s.close()
649
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
650
 
            return interface_index
651
 
    return if_nametoindex(interface)
652
 
 
653
 
 
654
 
def daemon(nochdir = False, noclose = False):
 
531
        SIOCGIFINDEX = 0x8933      # From /usr/include/linux/sockios.h
 
532
        s = socket.socket()
 
533
        ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
 
534
                            struct.pack("16s16x", interface))
 
535
        s.close()
 
536
        interface_index = struct.unpack("I", ifreq[16:20])[0]
 
537
        return interface_index
 
538
 
 
539
 
 
540
def daemon(nochdir, noclose):
655
541
    """See daemon(3).  Standard BSD Unix function.
656
542
    This should really exist as os.daemon, but it doesn't (yet)."""
657
543
    if os.fork():
659
545
    os.setsid()
660
546
    if not nochdir:
661
547
        os.chdir("/")
662
 
    if os.fork():
663
 
        sys.exit()
664
548
    if not noclose:
665
549
        # Close all standard open file descriptors
666
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
 
550
        null = os.open("/dev/null", os.O_NOCTTY | os.O_RDWR)
667
551
        if not stat.S_ISCHR(os.fstat(null).st_mode):
668
552
            raise OSError(errno.ENODEV,
669
553
                          "/dev/null not a character device")
674
558
            os.close(null)
675
559
 
676
560
 
677
 
def main():
678
 
    global main_loop_started
 
561
def killme(status = 0):
 
562
    logger.debug("Stopping server with exit status %d", status)
 
563
    exitstatus = status
 
564
    if main_loop_started:
 
565
        main_loop.quit()
 
566
    else:
 
567
        sys.exit(status)
 
568
 
 
569
 
 
570
if __name__ == '__main__':
 
571
    exitstatus = 0
679
572
    main_loop_started = False
680
 
    
681
 
    parser = OptionParser(version = "%%prog %s" % version)
 
573
    parser = OptionParser()
682
574
    parser.add_option("-i", "--interface", type="string",
683
 
                      metavar="IF", help="Bind to interface IF")
684
 
    parser.add_option("-a", "--address", type="string",
685
 
                      help="Address to listen for requests on")
686
 
    parser.add_option("-p", "--port", type="int",
 
575
                      default=None, metavar="IF",
 
576
                      help="Bind to interface IF")
 
577
    parser.add_option("-p", "--port", type="int", default=None,
687
578
                      help="Port number to receive requests on")
 
579
    parser.add_option("--timeout", type="string", # Parsed later
 
580
                      default="1h",
 
581
                      help="Amount of downtime allowed for clients")
 
582
    parser.add_option("--interval", type="string", # Parsed later
 
583
                      default="5m",
 
584
                      help="How often to check that a client is up")
688
585
    parser.add_option("--check", action="store_true", default=False,
689
586
                      help="Run self-test")
690
 
    parser.add_option("--debug", action="store_true",
691
 
                      help="Debug mode; run in foreground and log to"
692
 
                      " terminal")
693
 
    parser.add_option("--priority", type="string", help="GnuTLS"
694
 
                      " priority string (see GnuTLS documentation)")
695
 
    parser.add_option("--servicename", type="string", metavar="NAME",
696
 
                      help="Zeroconf service name")
697
 
    parser.add_option("--configdir", type="string",
698
 
                      default="/etc/mandos", metavar="DIR",
699
 
                      help="Directory to search for configuration"
700
 
                      " files")
 
587
    parser.add_option("--debug", action="store_true", default=False,
 
588
                      help="Debug mode")
701
589
    (options, args) = parser.parse_args()
702
590
    
703
591
    if options.check:
705
593
        doctest.testmod()
706
594
        sys.exit()
707
595
    
708
 
    # Default values for config file for server-global settings
709
 
    server_defaults = { "interface": "",
710
 
                        "address": "",
711
 
                        "port": "",
712
 
                        "debug": "False",
713
 
                        "priority":
714
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
715
 
                        "servicename": "Mandos",
716
 
                        }
717
 
    
718
 
    # Parse config file for server-global settings
719
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
720
 
    del server_defaults
721
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
722
 
    # Convert the SafeConfigParser object to a dict
723
 
    server_settings = server_config.defaults()
724
 
    # Use getboolean on the boolean config option
725
 
    server_settings["debug"] = server_config.getboolean\
726
 
                               ("DEFAULT", "debug")
727
 
    del server_config
728
 
    
729
 
    # Override the settings from the config file with command line
730
 
    # options, if set.
731
 
    for option in ("interface", "address", "port", "debug",
732
 
                   "priority", "servicename", "configdir"):
733
 
        value = getattr(options, option)
734
 
        if value is not None:
735
 
            server_settings[option] = value
736
 
    del options
737
 
    # Now we have our good server settings in "server_settings"
738
 
    
739
 
    debug = server_settings["debug"]
740
 
    
741
 
    if not debug:
742
 
        syslogger.setLevel(logging.WARNING)
743
 
        console.setLevel(logging.WARNING)
744
 
    
745
 
    if server_settings["servicename"] != "Mandos":
746
 
        syslogger.setFormatter(logging.Formatter\
747
 
                               ('Mandos (%s): %%(levelname)s:'
748
 
                                ' %%(message)s'
749
 
                                % server_settings["servicename"]))
750
 
    
751
 
    # Parse config file with clients
752
 
    client_defaults = { "timeout": "1h",
753
 
                        "interval": "5m",
754
 
                        "checker": "fping -q -- %(host)s",
755
 
                        "host": "",
756
 
                        }
757
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
758
 
    client_config.read(os.path.join(server_settings["configdir"],
759
 
                                    "clients.conf"))
760
 
    
761
 
    global service
762
 
    service = AvahiService(name = server_settings["servicename"],
763
 
                           type = "_mandos._tcp", );
764
 
    if server_settings["interface"]:
765
 
        service.interface = if_nametoindex\
766
 
                            (server_settings["interface"])
767
 
    
768
 
    global main_loop
769
 
    global bus
770
 
    global server
771
 
    # From the Avahi example code
 
596
    # Parse the time arguments
 
597
    try:
 
598
        options.timeout = string_to_delta(options.timeout)
 
599
    except ValueError:
 
600
        parser.error("option --timeout: Unparseable time")
 
601
    try:
 
602
        options.interval = string_to_delta(options.interval)
 
603
    except ValueError:
 
604
        parser.error("option --interval: Unparseable time")
 
605
    
 
606
    # Parse config file
 
607
    defaults = { "checker": "fping -q -- %%(fqdn)s" }
 
608
    client_config = ConfigParser.SafeConfigParser(defaults)
 
609
    #client_config.readfp(open("secrets.conf"), "secrets.conf")
 
610
    client_config.read("mandos-clients.conf")
 
611
    
 
612
    # From the Avahi server example code
772
613
    DBusGMainLoop(set_as_default=True )
773
614
    main_loop = gobject.MainLoop()
774
615
    bus = dbus.SystemBus()
775
 
    server = dbus.Interface(bus.get_object(avahi.DBUS_NAME,
776
 
                                           avahi.DBUS_PATH_SERVER),
777
 
                            avahi.DBUS_INTERFACE_SERVER)
 
616
    server = dbus.Interface(
 
617
            bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
 
618
            avahi.DBUS_INTERFACE_SERVER )
778
619
    # End of Avahi example code
779
620
    
 
621
    debug = options.debug
 
622
    
 
623
    if debug:
 
624
        console = logging.StreamHandler()
 
625
        # console.setLevel(logging.DEBUG)
 
626
        console.setFormatter(logging.Formatter\
 
627
                             ('%(levelname)s: %(message)s'))
 
628
        logger.addHandler(console)
 
629
        del console
 
630
    
780
631
    clients = Set()
781
632
    def remove_from_clients(client):
782
633
        clients.remove(client)
783
634
        if not clients:
784
 
            logger.critical(u"No clients left, exiting")
785
 
            sys.exit()
 
635
            logger.debug(u"No clients left, exiting")
 
636
            killme()
786
637
    
787
 
    clients.update(Set(Client(name = section,
 
638
    clients.update(Set(Client(name=section, options=options,
788
639
                              stop_hook = remove_from_clients,
789
 
                              config
790
 
                              = dict(client_config.items(section)))
 
640
                              **(dict(client_config\
 
641
                                      .items(section))))
791
642
                       for section in client_config.sections()))
792
 
    if not clients:
793
 
        logger.critical(u"No clients defined")
794
 
        sys.exit(1)
795
 
    
796
 
    if debug:
797
 
        # Redirect stdin so all checkers get /dev/null
798
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
799
 
        os.dup2(null, sys.stdin.fileno())
800
 
        if null > 2:
801
 
            os.close(null)
802
 
    else:
803
 
        # No console logging
804
 
        logger.removeHandler(console)
805
 
        # Close all input and output, do double fork, etc.
806
 
        daemon()
807
 
    
808
 
    pidfilename = "/var/run/mandos/mandos.pid"
809
 
    pid = os.getpid()
810
 
    try:
811
 
        pidfile = open(pidfilename, "w")
812
 
        pidfile.write(str(pid) + "\n")
813
 
        pidfile.close()
814
 
        del pidfile
815
 
    except IOError, err:
816
 
        logger.error(u"Could not write %s file with PID %d",
817
 
                     pidfilename, os.getpid())
 
643
    
 
644
    if not debug:
 
645
        daemon(False, False)
818
646
    
819
647
    def cleanup():
820
648
        "Cleanup function; run on exit"
821
649
        global group
822
 
        # From the Avahi example code
 
650
        # From the Avahi server example code
823
651
        if not group is None:
824
652
            group.Free()
825
653
            group = None
826
654
        # End of Avahi example code
827
655
        
828
 
        while clients:
829
 
            client = clients.pop()
 
656
        for client in clients:
830
657
            client.stop_hook = None
831
658
            client.stop()
832
659
    
834
661
    
835
662
    if not debug:
836
663
        signal.signal(signal.SIGINT, signal.SIG_IGN)
837
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
838
 
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
 
664
    signal.signal(signal.SIGHUP, lambda signum, frame: killme())
 
665
    signal.signal(signal.SIGTERM, lambda signum, frame: killme())
839
666
    
840
667
    for client in clients:
841
668
        client.start()
842
669
    
843
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
844
 
                                 server_settings["port"]),
 
670
    tcp_server = IPv6_TCPServer((None, options.port),
845
671
                                tcp_handler,
846
 
                                settings=server_settings,
 
672
                                options=options,
847
673
                                clients=clients)
848
 
    # Find out what port we got
849
 
    service.port = tcp_server.socket.getsockname()[1]
850
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
851
 
                u" scope_id %d" % tcp_server.socket.getsockname())
852
 
    
853
 
    #service.interface = tcp_server.socket.getsockname()[3]
854
 
    
855
 
    try:
856
 
        # From the Avahi example code
857
 
        server.connect_to_signal("StateChanged", server_state_changed)
858
 
        try:
859
 
            server_state_changed(server.GetState())
860
 
        except dbus.exceptions.DBusException, error:
861
 
            logger.critical(u"DBusException: %s", error)
862
 
            sys.exit(1)
863
 
        # End of Avahi example code
864
 
        
865
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
866
 
                             lambda *args, **kwargs:
867
 
                             tcp_server.handle_request\
868
 
                             (*args[2:], **kwargs) or True)
869
 
        
870
 
        logger.debug(u"Starting main loop")
 
674
    # Find out what random port we got
 
675
    servicePort = tcp_server.socket.getsockname()[1]
 
676
    logger.debug(u"Now listening on port %d", servicePort)
 
677
    
 
678
    if options.interface is not None:
 
679
        serviceInterface = if_nametoindex(options.interface)
 
680
    
 
681
    # From the Avahi server example code
 
682
    server.connect_to_signal("StateChanged", server_state_changed)
 
683
    try:
 
684
        server_state_changed(server.GetState())
 
685
    except dbus.exceptions.DBusException, error:
 
686
        logger.critical(u"DBusException: %s", error)
 
687
        killme(1)
 
688
    # End of Avahi example code
 
689
    
 
690
    gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
 
691
                         lambda *args, **kwargs:
 
692
                         tcp_server.handle_request(*args[2:],
 
693
                                                   **kwargs) or True)
 
694
    try:
871
695
        main_loop_started = True
872
696
        main_loop.run()
873
 
    except AvahiError, error:
874
 
        logger.critical(u"AvahiError: %s" + unicode(error))
875
 
        sys.exit(1)
876
697
    except KeyboardInterrupt:
877
698
        if debug:
878
699
            print
879
 
 
880
 
if __name__ == '__main__':
881
 
    main()
 
700
    
 
701
    sys.exit(exitstatus)