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  • Committer: Teddy Hogeborn
  • Date: 2008-08-25 06:44:13 UTC
  • Revision ID: teddy@fukt.bsnet.se-20080825064413-smqg5qwxfvhkeop4
* Makefile (DOCBOOKTOMAN): Only cd to one directory.

* mandos-options.xml (interface): Removed mention of a specific
                                  replaceable.
  (debug): Reworded slightly.

* mandos.conf.xml (OPTIONS): Renamed some replaceable names.

* mandos.xml (SYNOPSIS, OPTIONS): Renamed replaceable of "interface"
                                  from "IF" to "NAME".

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mandos
1
1
#!/usr/bin/python
 
2
# -*- mode: python; coding: utf-8 -*-
 
3
# 
 
4
# Mandos server - give out binary blobs to connecting clients.
 
5
# 
 
6
# This program is partly derived from an example program for an Avahi
 
7
# service publisher, downloaded from
 
8
# <http://avahi.org/wiki/PythonPublishExample>.  This includes the
 
9
# methods "add" and "remove" in the "AvahiService" class, the
 
10
# "server_state_changed" and "entry_group_state_changed" functions,
 
11
# and some lines in "main".
 
12
# 
 
13
# Everything else is
 
14
# Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
 
15
# 
 
16
# This program is free software: you can redistribute it and/or modify
 
17
# it under the terms of the GNU General Public License as published by
 
18
# the Free Software Foundation, either version 3 of the License, or
 
19
# (at your option) any later version.
 
20
#
 
21
#     This program is distributed in the hope that it will be useful,
 
22
#     but WITHOUT ANY WARRANTY; without even the implied warranty of
 
23
#     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 
24
#     GNU General Public License for more details.
 
25
# 
 
26
# You should have received a copy of the GNU General Public License
 
27
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
28
# 
 
29
# Contact the authors at <mandos@fukt.bsnet.se>.
 
30
# 
2
31
 
3
32
from __future__ import division
4
33
 
21
50
import signal
22
51
from sets import Set
23
52
import subprocess
 
53
import atexit
 
54
import stat
 
55
import logging
 
56
import logging.handlers
24
57
 
25
58
import dbus
26
59
import gobject
28
61
from dbus.mainloop.glib import DBusGMainLoop
29
62
import ctypes
30
63
 
31
 
import logging
32
 
import logging.handlers
33
 
 
34
 
# logghandler.setFormatter(logging.Formatter('%(levelname)s %(message)s')
 
64
version = "1.0"
35
65
 
36
66
logger = logging.Logger('mandos')
37
 
logger.addHandler(logging.handlers.SysLogHandler(facility = logging.handlers.SysLogHandler.LOG_DAEMON))
38
 
 
39
 
# This variable is used to optionally bind to a specified interface.
40
 
# It is a global variable to fit in with the other variables from the
41
 
# Avahi server example code.
42
 
serviceInterface = avahi.IF_UNSPEC
43
 
# From the Avahi server example code:
44
 
serviceName = "Mandos"
45
 
serviceType = "_mandos._tcp" # http://www.dns-sd.org/ServiceTypes.html
46
 
servicePort = None                      # Not known at startup
47
 
serviceTXT = []                         # TXT record for the service
48
 
domain = ""                  # Domain to publish on, default to .local
49
 
host = ""          # Host to publish records for, default to localhost
50
 
group = None #our entry group
51
 
rename_count = 12       # Counter so we only rename after collisions a
52
 
                        # sensible number of times
 
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
53
165
# End of Avahi example code
54
166
 
55
167
 
60
172
    fingerprint: string (40 or 32 hexadecimal digits); used to
61
173
                 uniquely identify the client
62
174
    secret:    bytestring; sent verbatim (over TLS) to client
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
 
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
68
180
    interval:  datetime.timedelta(); How often to start a new checker
69
181
    stop_hook: If set, called by stop() as stop_hook(self)
70
182
    checker:   subprocess.Popen(); a running checker process used
71
183
                                   to see if the client lives.
72
 
                                   Is None if no process is running.
 
184
                                   'None' if no process is running.
73
185
    checker_initiator_tag: a gobject event source tag, or None
74
186
    stop_initiator_tag:    - '' -
75
187
    checker_callback_tag:  - '' -
76
188
    checker_command: string; External command which is run to check if
77
 
                     client lives.  %()s expansions are done at
 
189
                     client lives.  %() expansions are done at
78
190
                     runtime with vars(self) as dict, so that for
79
191
                     instance %(name)s can be used in the command.
80
192
    Private attibutes:
81
193
    _timeout: Real variable for 'timeout'
82
194
    _interval: Real variable for 'interval'
83
 
    _timeout_milliseconds: Used by gobject.timeout_add()
 
195
    _timeout_milliseconds: Used when calling gobject.timeout_add()
84
196
    _interval_milliseconds: - '' -
85
197
    """
86
198
    def _set_timeout(self, timeout):
106
218
    interval = property(lambda self: self._interval,
107
219
                        _set_interval)
108
220
    del _set_interval
109
 
    def __init__(self, name=None, options=None, stop_hook=None,
110
 
                 fingerprint=None, secret=None, secfile=None, fqdn=None,
111
 
                 timeout=None, interval=-1, checker=None):
 
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."""
112
225
        self.name = name
113
 
        # Uppercase and remove spaces from fingerprint
114
 
        # for later comparison purposes with return value of
115
 
        # the fingerprint() function
116
 
        self.fingerprint = fingerprint.upper().replace(u" ", u"")
117
 
        if secret:
118
 
            self.secret = secret.decode(u"base64")
119
 
        elif secfile:
120
 
            sf = open(secfile)
 
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"])
121
237
            self.secret = sf.read()
122
238
            sf.close()
123
239
        else:
124
 
            raise RuntimeError(u"No secret or secfile for client %s"
125
 
                               % self.name)
126
 
        self.fqdn = fqdn                # string
 
240
            raise TypeError(u"No secret or secfile for client %s"
 
241
                            % self.name)
 
242
        self.host = config.get("host", "")
127
243
        self.created = datetime.datetime.now()
128
 
        self.last_seen = None
129
 
        if timeout is None:
130
 
            timeout = options.timeout
131
 
        self.timeout = timeout
132
 
        if interval == -1:
133
 
            interval = options.interval
134
 
        else:
135
 
            interval = string_to_delta(interval)
136
 
        self.interval = interval
 
244
        self.last_checked_ok = None
 
245
        self.timeout = string_to_delta(config["timeout"])
 
246
        self.interval = string_to_delta(config["interval"])
137
247
        self.stop_hook = stop_hook
138
248
        self.checker = None
139
249
        self.checker_initiator_tag = None
140
250
        self.stop_initiator_tag = None
141
251
        self.checker_callback_tag = None
142
 
        self.check_command = checker
 
252
        self.check_command = config["checker"]
143
253
    def start(self):
144
 
        """Start this clients checker and timeout hooks"""
 
254
        """Start this client's checker and timeout hooks"""
145
255
        # Schedule a new checker to be started an 'interval' from now,
146
256
        # and every interval from then on.
147
257
        self.checker_initiator_tag = gobject.timeout_add\
155
265
                                   self.stop)
156
266
    def stop(self):
157
267
        """Stop this client.
158
 
        The possibility that this client might be restarted is left
159
 
        open, but not currently used."""
160
 
        logger.debug(u"Stopping client %s", self.name)
161
 
        self.secret = None
162
 
        if self.stop_initiator_tag:
 
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):
163
277
            gobject.source_remove(self.stop_initiator_tag)
164
278
            self.stop_initiator_tag = None
165
 
        if self.checker_initiator_tag:
 
279
        if getattr(self, "checker_initiator_tag", False):
166
280
            gobject.source_remove(self.checker_initiator_tag)
167
281
            self.checker_initiator_tag = None
168
282
        self.stop_checker()
171
285
        # Do not run this again if called by a gobject.timeout_add
172
286
        return False
173
287
    def __del__(self):
174
 
        # Some code duplication here and in stop()
175
 
        if hasattr(self, "stop_initiator_tag") \
176
 
               and self.stop_initiator_tag:
177
 
            gobject.source_remove(self.stop_initiator_tag)
178
 
            self.stop_initiator_tag = None
179
 
        if hasattr(self, "checker_initiator_tag") \
180
 
               and self.checker_initiator_tag:
181
 
            gobject.source_remove(self.checker_initiator_tag)
182
 
            self.checker_initiator_tag = None
183
 
        self.stop_checker()
 
288
        self.stop_hook = None
 
289
        self.stop()
184
290
    def checker_callback(self, pid, condition):
185
291
        """The checker has completed, so take appropriate actions."""
186
292
        now = datetime.datetime.now()
 
293
        self.checker_callback_tag = None
 
294
        self.checker = None
187
295
        if os.WIFEXITED(condition) \
188
296
               and (os.WEXITSTATUS(condition) == 0):
189
 
            logger.debug(u"Checker for %(name)s succeeded",
190
 
                         vars(self))
191
 
            self.last_seen = now
 
297
            logger.info(u"Checker for %(name)s succeeded",
 
298
                        vars(self))
 
299
            self.last_checked_ok = now
192
300
            gobject.source_remove(self.stop_initiator_tag)
193
301
            self.stop_initiator_tag = gobject.timeout_add\
194
302
                                      (self._timeout_milliseconds,
195
303
                                       self.stop)
196
 
        if not os.WIFEXITED(condition):
 
304
        elif not os.WIFEXITED(condition):
197
305
            logger.warning(u"Checker for %(name)s crashed?",
198
306
                           vars(self))
199
307
        else:
200
 
            logger.debug(u"Checker for %(name)s failed",
201
 
                         vars(self))
202
 
            self.checker = None
203
 
        self.checker_callback_tag = None
 
308
            logger.info(u"Checker for %(name)s failed",
 
309
                        vars(self))
204
310
    def start_checker(self):
205
311
        """Start a new checker subprocess if one is not running.
206
312
        If a checker already exists, leave it running and do
207
313
        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.
208
322
        if self.checker is None:
209
 
            logger.debug(u"Starting checker for %s",
210
 
                         self.name)
211
323
            try:
212
 
                command = self.check_command % self.fqdn
 
324
                # In case check_command has exactly one % operator
 
325
                command = self.check_command % self.host
213
326
            except TypeError:
 
327
                # Escape attributes for the shell
214
328
                escaped_attrs = dict((key, re.escape(str(val)))
215
329
                                     for key, val in
216
330
                                     vars(self).iteritems())
217
331
                try:
218
332
                    command = self.check_command % escaped_attrs
219
333
                except TypeError, error:
220
 
                    logger.critical(u'Could not format string "%s": %s',
221
 
                                    self.check_command, error)
 
334
                    logger.error(u'Could not format string "%s":'
 
335
                                 u' %s', self.check_command, error)
222
336
                    return True # Try again later
223
337
            try:
224
 
                self.checker = subprocess.\
225
 
                               Popen(command,
226
 
                                     stdout=subprocess.PIPE,
227
 
                                     close_fds=True, shell=True,
228
 
                                     cwd="/")
229
 
                self.checker_callback_tag = gobject.\
230
 
                                            child_watch_add(self.checker.pid,
231
 
                                                            self.\
232
 
                                                            checker_callback)
233
 
            except subprocess.OSError, error:
 
338
                logger.info(u"Starting checker %r for %s",
 
339
                            command, self.name)
 
340
                # We don't need to redirect stdout and stderr, since
 
341
                # in normal mode, that is already done by daemon(),
 
342
                # and in debug mode we don't want to.  (Stdin is
 
343
                # always replaced by /dev/null.)
 
344
                self.checker = subprocess.Popen(command,
 
345
                                                close_fds=True,
 
346
                                                shell=True, cwd="/")
 
347
                self.checker_callback_tag = gobject.child_watch_add\
 
348
                                            (self.checker.pid,
 
349
                                             self.checker_callback)
 
350
            except OSError, error:
234
351
                logger.error(u"Failed to start subprocess: %s",
235
352
                             error)
236
353
        # Re-run this periodically if run by gobject.timeout_add
237
354
        return True
238
355
    def stop_checker(self):
239
356
        """Force the checker process, if any, to stop."""
240
 
        if not hasattr(self, "checker") or self.checker is None:
 
357
        if self.checker_callback_tag:
 
358
            gobject.source_remove(self.checker_callback_tag)
 
359
            self.checker_callback_tag = None
 
360
        if getattr(self, "checker", None) is None:
241
361
            return
242
 
        gobject.source_remove(self.checker_callback_tag)
243
 
        self.checker_callback_tag = None
244
 
        os.kill(self.checker.pid, signal.SIGTERM)
245
 
        if self.checker.poll() is None:
246
 
            os.kill(self.checker.pid, signal.SIGKILL)
 
362
        logger.debug(u"Stopping checker for %(name)s", vars(self))
 
363
        try:
 
364
            os.kill(self.checker.pid, signal.SIGTERM)
 
365
            #os.sleep(0.5)
 
366
            #if self.checker.poll() is None:
 
367
            #    os.kill(self.checker.pid, signal.SIGKILL)
 
368
        except OSError, error:
 
369
            if error.errno != errno.ESRCH: # No such process
 
370
                raise
247
371
        self.checker = None
248
 
    def still_valid(self, now=None):
 
372
    def still_valid(self):
249
373
        """Has the timeout not yet passed for this client?"""
250
 
        if now is None:
251
 
            now = datetime.datetime.now()
252
 
        if self.last_seen is None:
 
374
        now = datetime.datetime.now()
 
375
        if self.last_checked_ok is None:
253
376
            return now < (self.created + self.timeout)
254
377
        else:
255
 
            return now < (self.last_seen + self.timeout)
 
378
            return now < (self.last_checked_ok + self.timeout)
256
379
 
257
380
 
258
381
def peer_certificate(session):
 
382
    "Return the peer's OpenPGP certificate as a bytestring"
259
383
    # If not an OpenPGP certificate...
260
384
    if gnutls.library.functions.gnutls_certificate_type_get\
261
385
            (session._c_object) \
272
396
 
273
397
 
274
398
def fingerprint(openpgp):
275
 
    # New empty GnuTLS certificate
276
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
277
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
278
 
        (ctypes.byref(crt))
 
399
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
279
400
    # New GnuTLS "datum" with the OpenPGP public key
280
401
    datum = gnutls.library.types.gnutls_datum_t\
281
402
        (ctypes.cast(ctypes.c_char_p(openpgp),
282
403
                     ctypes.POINTER(ctypes.c_ubyte)),
283
404
         ctypes.c_uint(len(openpgp)))
 
405
    # New empty GnuTLS certificate
 
406
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
407
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
408
        (ctypes.byref(crt))
284
409
    # Import the OpenPGP public key into the certificate
285
 
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
286
 
        (crt,
287
 
         ctypes.byref(datum),
288
 
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
 
410
    gnutls.library.functions.gnutls_openpgp_crt_import\
 
411
                    (crt, ctypes.byref(datum),
 
412
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
 
413
    # Verify the self signature in the key
 
414
    crtverify = ctypes.c_uint();
 
415
    gnutls.library.functions.gnutls_openpgp_crt_verify_self\
 
416
        (crt, ctypes.c_uint(0), ctypes.byref(crtverify))
 
417
    if crtverify.value != 0:
 
418
        gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
 
419
        raise gnutls.errors.CertificateSecurityError("Verify failed")
289
420
    # New buffer for the fingerprint
290
421
    buffer = ctypes.create_string_buffer(20)
291
422
    buffer_length = ctypes.c_size_t()
307
438
    Note: This will run in its own forked process."""
308
439
    
309
440
    def handle(self):
310
 
        logger.debug(u"TCP connection from: %s",
 
441
        logger.info(u"TCP connection from: %s",
311
442
                     unicode(self.client_address))
312
 
        session = gnutls.connection.ClientSession(self.request,
313
 
                                                  gnutls.connection.\
314
 
                                                  X509Credentials())
 
443
        session = gnutls.connection.ClientSession\
 
444
                  (self.request, gnutls.connection.X509Credentials())
 
445
        
 
446
        line = self.request.makefile().readline()
 
447
        logger.debug(u"Protocol version: %r", line)
 
448
        try:
 
449
            if int(line.strip().split()[0]) > 1:
 
450
                raise RuntimeError
 
451
        except (ValueError, IndexError, RuntimeError), error:
 
452
            logger.error(u"Unknown protocol version: %s", error)
 
453
            return
 
454
        
 
455
        # Note: gnutls.connection.X509Credentials is really a generic
 
456
        # GnuTLS certificate credentials object so long as no X.509
 
457
        # keys are added to it.  Therefore, we can use it here despite
 
458
        # using OpenPGP certificates.
315
459
        
316
460
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
317
461
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
318
462
        #                "+DHE-DSS"))
319
 
        priority = "SECURE256"
320
 
        
 
463
        priority = "NORMAL"             # Fallback default, since this
 
464
                                        # MUST be set.
 
465
        if self.server.settings["priority"]:
 
466
            priority = self.server.settings["priority"]
321
467
        gnutls.library.functions.gnutls_priority_set_direct\
322
468
            (session._c_object, priority, None);
323
469
        
324
470
        try:
325
471
            session.handshake()
326
472
        except gnutls.errors.GNUTLSError, error:
327
 
            logger.debug(u"Handshake failed: %s", error)
 
473
            logger.warning(u"Handshake failed: %s", error)
328
474
            # Do not run session.bye() here: the session is not
329
475
            # established.  Just abandon the request.
330
476
            return
331
477
        try:
332
478
            fpr = fingerprint(peer_certificate(session))
333
479
        except (TypeError, gnutls.errors.GNUTLSError), error:
334
 
            logger.debug(u"Bad certificate: %s", error)
 
480
            logger.warning(u"Bad certificate: %s", error)
335
481
            session.bye()
336
482
            return
337
483
        logger.debug(u"Fingerprint: %s", fpr)
338
484
        client = None
339
 
        for c in clients:
 
485
        for c in self.server.clients:
340
486
            if c.fingerprint == fpr:
341
487
                client = c
342
488
                break
 
489
        if not client:
 
490
            logger.warning(u"Client not found for fingerprint: %s",
 
491
                           fpr)
 
492
            session.bye()
 
493
            return
343
494
        # Have to check if client.still_valid(), since it is possible
344
495
        # that the client timed out while establishing the GnuTLS
345
496
        # session.
346
 
        if (not client) or (not client.still_valid()):
347
 
            if client:
348
 
                logger.debug(u"Client %(name)s is invalid",
349
 
                             vars(client))
350
 
            else:
351
 
                logger.debug(u"Client not found for fingerprint: %s",
352
 
                             fpr)
 
497
        if not client.still_valid():
 
498
            logger.warning(u"Client %(name)s is invalid",
 
499
                           vars(client))
353
500
            session.bye()
354
501
            return
355
502
        sent_size = 0
365
512
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
366
513
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
367
514
    Attributes:
368
 
        options:        Command line options
 
515
        settings:       Server settings
369
516
        clients:        Set() of Client objects
370
517
    """
371
518
    address_family = socket.AF_INET6
372
519
    def __init__(self, *args, **kwargs):
373
 
        if "options" in kwargs:
374
 
            self.options = kwargs["options"]
375
 
            del kwargs["options"]
 
520
        if "settings" in kwargs:
 
521
            self.settings = kwargs["settings"]
 
522
            del kwargs["settings"]
376
523
        if "clients" in kwargs:
377
524
            self.clients = kwargs["clients"]
378
525
            del kwargs["clients"]
381
528
        """This overrides the normal server_bind() function
382
529
        to bind to an interface if one was specified, and also NOT to
383
530
        bind to an address or port if they were not specified."""
384
 
        if self.options.interface:
385
 
            if not hasattr(socket, "SO_BINDTODEVICE"):
386
 
                # From /usr/include/asm-i486/socket.h
387
 
                socket.SO_BINDTODEVICE = 25
 
531
        if self.settings["interface"]:
 
532
            # 25 is from /usr/include/asm-i486/socket.h
 
533
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
388
534
            try:
389
535
                self.socket.setsockopt(socket.SOL_SOCKET,
390
 
                                       socket.SO_BINDTODEVICE,
391
 
                                       self.options.interface)
 
536
                                       SO_BINDTODEVICE,
 
537
                                       self.settings["interface"])
392
538
            except socket.error, error:
393
539
                if error[0] == errno.EPERM:
394
 
                    logger.warning(u"No permission to"
395
 
                                   u" bind to interface %s",
396
 
                                   self.options.interface)
 
540
                    logger.error(u"No permission to"
 
541
                                 u" bind to interface %s",
 
542
                                 self.settings["interface"])
397
543
                else:
398
544
                    raise error
399
545
        # Only bind(2) the socket if we really need to.
402
548
                in6addr_any = "::"
403
549
                self.server_address = (in6addr_any,
404
550
                                       self.server_address[1])
405
 
            elif self.server_address[1] is None:
 
551
            elif not self.server_address[1]:
406
552
                self.server_address = (self.server_address[0],
407
553
                                       0)
 
554
#                 if self.settings["interface"]:
 
555
#                     self.server_address = (self.server_address[0],
 
556
#                                            0, # port
 
557
#                                            0, # flowinfo
 
558
#                                            if_nametoindex
 
559
#                                            (self.settings
 
560
#                                             ["interface"]))
408
561
            return super(type(self), self).server_bind()
409
562
 
410
563
 
421
574
    datetime.timedelta(1)
422
575
    >>> string_to_delta(u'1w')
423
576
    datetime.timedelta(7)
 
577
    >>> string_to_delta('5m 30s')
 
578
    datetime.timedelta(0, 330)
424
579
    """
425
 
    try:
426
 
        suffix=unicode(interval[-1])
427
 
        value=int(interval[:-1])
428
 
        if suffix == u"d":
429
 
            delta = datetime.timedelta(value)
430
 
        elif suffix == u"s":
431
 
            delta = datetime.timedelta(0, value)
432
 
        elif suffix == u"m":
433
 
            delta = datetime.timedelta(0, 0, 0, 0, value)
434
 
        elif suffix == u"h":
435
 
            delta = datetime.timedelta(0, 0, 0, 0, 0, value)
436
 
        elif suffix == u"w":
437
 
            delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
438
 
        else:
 
580
    timevalue = datetime.timedelta(0)
 
581
    for s in interval.split():
 
582
        try:
 
583
            suffix=unicode(s[-1])
 
584
            value=int(s[:-1])
 
585
            if suffix == u"d":
 
586
                delta = datetime.timedelta(value)
 
587
            elif suffix == u"s":
 
588
                delta = datetime.timedelta(0, value)
 
589
            elif suffix == u"m":
 
590
                delta = datetime.timedelta(0, 0, 0, 0, value)
 
591
            elif suffix == u"h":
 
592
                delta = datetime.timedelta(0, 0, 0, 0, 0, value)
 
593
            elif suffix == u"w":
 
594
                delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
 
595
            else:
 
596
                raise ValueError
 
597
        except (ValueError, IndexError):
439
598
            raise ValueError
440
 
    except (ValueError, IndexError):
441
 
        raise ValueError
442
 
    return delta
443
 
 
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()
 
599
        timevalue += delta
 
600
    return timevalue
476
601
 
477
602
 
478
603
def server_state_changed(state):
479
 
    """From the Avahi server example code"""
 
604
    """Derived from the Avahi example code"""
480
605
    if state == avahi.SERVER_COLLISION:
481
 
        logger.warning(u"Server name collision")
482
 
        remove_service()
 
606
        logger.error(u"Server name collision")
 
607
        service.remove()
483
608
    elif state == avahi.SERVER_RUNNING:
484
 
        add_service()
 
609
        service.add()
485
610
 
486
611
 
487
612
def entry_group_state_changed(state, error):
488
 
    """From the Avahi server example code"""
489
 
    global serviceName, server, rename_count
490
 
    
 
613
    """Derived from the Avahi example code"""
491
614
    logger.debug(u"state change: %i", state)
492
615
    
493
616
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
494
617
        logger.debug(u"Service established.")
495
618
    elif state == avahi.ENTRY_GROUP_COLLISION:
496
 
        
497
 
        rename_count = rename_count - 1
498
 
        if rename_count > 0:
499
 
            name = server.GetAlternativeServiceName(name)
500
 
            logger.warning(u"Service name collision, "
501
 
                           u"changing name to '%s' ...", name)
502
 
            remove_service()
503
 
            add_service()
504
 
            
505
 
        else:
506
 
            logger.error(u"No suitable service name found "
507
 
                         u"after %i retries, exiting.",
508
 
                         n_rename)
509
 
            main_loop.quit()
 
619
        logger.warning(u"Service name collision.")
 
620
        service.rename()
510
621
    elif state == avahi.ENTRY_GROUP_FAILURE:
511
 
        logger.error(u"Error in group state changed %s",
512
 
                     unicode(error))
513
 
        main_loop.quit()
514
 
        return
515
 
 
 
622
        logger.critical(u"Error in group state changed %s",
 
623
                        unicode(error))
 
624
        raise AvahiGroupError("State changed: %s", str(error))
516
625
 
517
626
def if_nametoindex(interface):
518
 
    """Call the C function if_nametoindex()"""
 
627
    """Call the C function if_nametoindex(), or equivalent"""
 
628
    global if_nametoindex
519
629
    try:
520
 
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
521
 
        return libc.if_nametoindex(interface)
 
630
        if "ctypes.util" not in sys.modules:
 
631
            import ctypes.util
 
632
        if_nametoindex = ctypes.cdll.LoadLibrary\
 
633
            (ctypes.util.find_library("c")).if_nametoindex
522
634
    except (OSError, AttributeError):
523
635
        if "struct" not in sys.modules:
524
636
            import struct
525
637
        if "fcntl" not in sys.modules:
526
638
            import fcntl
527
 
        SIOCGIFINDEX = 0x8933      # From /usr/include/linux/sockios.h
528
 
        s = socket.socket()
529
 
        ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
530
 
                            struct.pack("16s16x", interface))
531
 
        s.close()
532
 
        interface_index = struct.unpack("I", ifreq[16:20])[0]
533
 
        return interface_index
534
 
 
535
 
 
536
 
if __name__ == '__main__':
537
 
    parser = OptionParser()
 
639
        def if_nametoindex(interface):
 
640
            "Get an interface index the hard way, i.e. using fcntl()"
 
641
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
 
642
            s = socket.socket()
 
643
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
 
644
                                struct.pack("16s16x", interface))
 
645
            s.close()
 
646
            interface_index = struct.unpack("I", ifreq[16:20])[0]
 
647
            return interface_index
 
648
    return if_nametoindex(interface)
 
649
 
 
650
 
 
651
def daemon(nochdir = False, noclose = False):
 
652
    """See daemon(3).  Standard BSD Unix function.
 
653
    This should really exist as os.daemon, but it doesn't (yet)."""
 
654
    if os.fork():
 
655
        sys.exit()
 
656
    os.setsid()
 
657
    if not nochdir:
 
658
        os.chdir("/")
 
659
    if os.fork():
 
660
        sys.exit()
 
661
    if not noclose:
 
662
        # Close all standard open file descriptors
 
663
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
 
664
        if not stat.S_ISCHR(os.fstat(null).st_mode):
 
665
            raise OSError(errno.ENODEV,
 
666
                          "/dev/null not a character device")
 
667
        os.dup2(null, sys.stdin.fileno())
 
668
        os.dup2(null, sys.stdout.fileno())
 
669
        os.dup2(null, sys.stderr.fileno())
 
670
        if null > 2:
 
671
            os.close(null)
 
672
 
 
673
 
 
674
def main():
 
675
    global main_loop_started
 
676
    main_loop_started = False
 
677
    
 
678
    parser = OptionParser(version = "%%prog %s" % version)
538
679
    parser.add_option("-i", "--interface", type="string",
539
 
                      default=None, metavar="IF",
540
 
                      help="Bind to interface IF")
541
 
    parser.add_option("--cert", type="string", default="cert.pem",
542
 
                      metavar="FILE",
543
 
                      help="Public key certificate PEM file to use")
544
 
    parser.add_option("--key", type="string", default="key.pem",
545
 
                      metavar="FILE",
546
 
                      help="Private key PEM file to use")
547
 
    parser.add_option("--ca", type="string", default="ca.pem",
548
 
                      metavar="FILE",
549
 
                      help="Certificate Authority certificate PEM file to use")
550
 
    parser.add_option("--crl", type="string", default="crl.pem",
551
 
                      metavar="FILE",
552
 
                      help="Certificate Revokation List PEM file to use")
553
 
    parser.add_option("-p", "--port", type="int", default=None,
 
680
                      metavar="IF", help="Bind to interface IF")
 
681
    parser.add_option("-a", "--address", type="string",
 
682
                      help="Address to listen for requests on")
 
683
    parser.add_option("-p", "--port", type="int",
554
684
                      help="Port number to receive requests on")
555
 
    parser.add_option("--timeout", type="string", # Parsed later
556
 
                      default="1h",
557
 
                      help="Amount of downtime allowed for clients")
558
 
    parser.add_option("--interval", type="string", # Parsed later
559
 
                      default="5m",
560
 
                      help="How often to check that a client is up")
561
685
    parser.add_option("--check", action="store_true", default=False,
562
686
                      help="Run self-test")
563
 
    parser.add_option("--debug", action="store_true", default=False,
564
 
                      help="Debug mode")
 
687
    parser.add_option("--debug", action="store_true",
 
688
                      help="Debug mode; run in foreground and log to"
 
689
                      " terminal")
 
690
    parser.add_option("--priority", type="string", help="GnuTLS"
 
691
                      " priority string (see GnuTLS documentation)")
 
692
    parser.add_option("--servicename", type="string", metavar="NAME",
 
693
                      help="Zeroconf service name")
 
694
    parser.add_option("--configdir", type="string",
 
695
                      default="/etc/mandos", metavar="DIR",
 
696
                      help="Directory to search for configuration"
 
697
                      " files")
565
698
    (options, args) = parser.parse_args()
566
699
    
567
700
    if options.check:
569
702
        doctest.testmod()
570
703
        sys.exit()
571
704
    
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
 
705
    # Default values for config file for server-global settings
 
706
    server_defaults = { "interface": "",
 
707
                        "address": "",
 
708
                        "port": "",
 
709
                        "debug": "False",
 
710
                        "priority":
 
711
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
 
712
                        "servicename": "Mandos",
 
713
                        }
 
714
    
 
715
    # Parse config file for server-global settings
 
716
    server_config = ConfigParser.SafeConfigParser(server_defaults)
 
717
    del server_defaults
 
718
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
 
719
    # Convert the SafeConfigParser object to a dict
 
720
    server_settings = server_config.defaults()
 
721
    # Use getboolean on the boolean config option
 
722
    server_settings["debug"] = server_config.getboolean\
 
723
                               ("DEFAULT", "debug")
 
724
    del server_config
 
725
    
 
726
    # Override the settings from the config file with command line
 
727
    # options, if set.
 
728
    for option in ("interface", "address", "port", "debug",
 
729
                   "priority", "servicename", "configdir"):
 
730
        value = getattr(options, option)
 
731
        if value is not None:
 
732
            server_settings[option] = value
 
733
    del options
 
734
    # Now we have our good server settings in "server_settings"
 
735
    
 
736
    debug = server_settings["debug"]
 
737
    
 
738
    if not debug:
 
739
        syslogger.setLevel(logging.WARNING)
 
740
        console.setLevel(logging.WARNING)
 
741
    
 
742
    if server_settings["servicename"] != "Mandos":
 
743
        syslogger.setFormatter(logging.Formatter\
 
744
                               ('Mandos (%s): %%(levelname)s:'
 
745
                                ' %%(message)s'
 
746
                                % server_settings["servicename"]))
 
747
    
 
748
    # Parse config file with clients
 
749
    client_defaults = { "timeout": "1h",
 
750
                        "interval": "5m",
 
751
                        "checker": "fping -q -- %(host)s",
 
752
                        "host": "",
 
753
                        }
 
754
    client_config = ConfigParser.SafeConfigParser(client_defaults)
 
755
    client_config.read(os.path.join(server_settings["configdir"],
 
756
                                    "clients.conf"))
 
757
    
 
758
    global service
 
759
    service = AvahiService(name = server_settings["servicename"],
 
760
                           type = "_mandos._tcp", );
 
761
    if server_settings["interface"]:
 
762
        service.interface = if_nametoindex(server_settings["interface"])
 
763
    
 
764
    global main_loop
 
765
    global bus
 
766
    global server
 
767
    # From the Avahi example code
589
768
    DBusGMainLoop(set_as_default=True )
590
769
    main_loop = gobject.MainLoop()
591
770
    bus = dbus.SystemBus()
594
773
            avahi.DBUS_INTERFACE_SERVER )
595
774
    # End of Avahi example code
596
775
    
597
 
    debug = options.debug
598
 
    
599
776
    clients = Set()
600
777
    def remove_from_clients(client):
601
778
        clients.remove(client)
602
779
        if not clients:
603
 
            logger.debug(u"No clients left, exiting")
604
 
            main_loop.quit()
 
780
            logger.critical(u"No clients left, exiting")
 
781
            sys.exit()
605
782
    
606
 
    clients.update(Set(Client(name=section, options=options,
 
783
    clients.update(Set(Client(name = section,
607
784
                              stop_hook = remove_from_clients,
608
 
                              **(dict(client_config\
609
 
                                      .items(section))))
 
785
                              config
 
786
                              = dict(client_config.items(section)))
610
787
                       for section in client_config.sections()))
 
788
    if not clients:
 
789
        logger.critical(u"No clients defined")
 
790
        sys.exit(1)
 
791
    
 
792
    if debug:
 
793
        # Redirect stdin so all checkers get /dev/null
 
794
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
 
795
        os.dup2(null, sys.stdin.fileno())
 
796
        if null > 2:
 
797
            os.close(null)
 
798
    else:
 
799
        # No console logging
 
800
        logger.removeHandler(console)
 
801
        # Close all input and output, do double fork, etc.
 
802
        daemon()
 
803
    
 
804
    pidfilename = "/var/run/mandos/mandos.pid"
 
805
    pid = os.getpid()
 
806
    try:
 
807
        pidfile = open(pidfilename, "w")
 
808
        pidfile.write(str(pid) + "\n")
 
809
        pidfile.close()
 
810
        del pidfile
 
811
    except IOError, err:
 
812
        logger.error(u"Could not write %s file with PID %d",
 
813
                     pidfilename, os.getpid())
 
814
    
 
815
    def cleanup():
 
816
        "Cleanup function; run on exit"
 
817
        global group
 
818
        # From the Avahi example code
 
819
        if not group is None:
 
820
            group.Free()
 
821
            group = None
 
822
        # End of Avahi example code
 
823
        
 
824
        while clients:
 
825
            client = clients.pop()
 
826
            client.stop_hook = None
 
827
            client.stop()
 
828
    
 
829
    atexit.register(cleanup)
 
830
    
 
831
    if not debug:
 
832
        signal.signal(signal.SIGINT, signal.SIG_IGN)
 
833
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
 
834
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
 
835
    
611
836
    for client in clients:
612
837
        client.start()
613
838
    
614
 
    tcp_server = IPv6_TCPServer((None, options.port),
 
839
    tcp_server = IPv6_TCPServer((server_settings["address"],
 
840
                                 server_settings["port"]),
615
841
                                tcp_handler,
616
 
                                options=options,
 
842
                                settings=server_settings,
617
843
                                clients=clients)
618
 
    # Find out what random port we got
619
 
    servicePort = tcp_server.socket.getsockname()[1]
620
 
    logger.debug(u"Now listening on port %d", servicePort)
621
 
    
622
 
    if options.interface is not None:
623
 
        serviceInterface = if_nametoindex(options.interface)
624
 
    
625
 
    # From the Avahi server example code
626
 
    server.connect_to_signal("StateChanged", server_state_changed)
627
 
    server_state_changed(server.GetState())
628
 
    # End of Avahi example code
629
 
    
630
 
    gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
631
 
                         lambda *args, **kwargs:
632
 
                         tcp_server.handle_request(*args[2:],
633
 
                                                   **kwargs) or True)
 
844
    # Find out what port we got
 
845
    service.port = tcp_server.socket.getsockname()[1]
 
846
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
 
847
                u" scope_id %d" % tcp_server.socket.getsockname())
 
848
    
 
849
    #service.interface = tcp_server.socket.getsockname()[3]
 
850
    
634
851
    try:
 
852
        # From the Avahi example code
 
853
        server.connect_to_signal("StateChanged", server_state_changed)
 
854
        try:
 
855
            server_state_changed(server.GetState())
 
856
        except dbus.exceptions.DBusException, error:
 
857
            logger.critical(u"DBusException: %s", error)
 
858
            sys.exit(1)
 
859
        # End of Avahi example code
 
860
        
 
861
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
 
862
                             lambda *args, **kwargs:
 
863
                             tcp_server.handle_request\
 
864
                             (*args[2:], **kwargs) or True)
 
865
        
 
866
        logger.debug(u"Starting main loop")
 
867
        main_loop_started = True
635
868
        main_loop.run()
 
869
    except AvahiError, error:
 
870
        logger.critical(u"AvahiError: %s" + unicode(error))
 
871
        sys.exit(1)
636
872
    except KeyboardInterrupt:
637
 
        print
638
 
    
639
 
    # Cleanup here
 
873
        if debug:
 
874
            print
640
875
 
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()
 
876
if __name__ == '__main__':
 
877
    main()