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  • Committer: Teddy Hogeborn
  • Date: 2007-12-19 07:58:13 UTC
  • Revision ID: teddy@fukt.bsnet.se-20071219075813-5u1w3gujvttj83qs
* server.py (Client.created, Client.next_check): New.
  (string_to_delta): New.
  (main): New options "--check" and "--interval".  Use string_to_delta to
  parse arguments to "--timeout" and "--interval".

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#!/usr/bin/python
2
 
# -*- mode: python; coding: utf-8 -*-
3
 
4
 
# Mandos server - give out binary blobs to connecting clients.
5
 
6
 
# This program is partly derived from an example program for an Avahi
7
 
# service publisher, downloaded from
8
 
# <http://avahi.org/wiki/PythonPublishExample>.  This includes the
9
 
# methods "add" and "remove" in the "AvahiService" class, the
10
 
# "server_state_changed" and "entry_group_state_changed" functions,
11
 
# and some lines in "main".
12
 
13
 
# Everything else is
14
 
# Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
15
 
16
 
# This program is free software: you can redistribute it and/or modify
17
 
# it under the terms of the GNU General Public License as published by
18
 
# the Free Software Foundation, either version 3 of the License, or
19
 
# (at your option) any later version.
20
 
#
21
 
#     This program is distributed in the hope that it will be useful,
22
 
#     but WITHOUT ANY WARRANTY; without even the implied warranty of
23
 
#     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24
 
#     GNU General Public License for more details.
25
 
26
 
# You should have received a copy of the GNU General Public License
27
 
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
28
 
29
 
# Contact the authors at <mandos@fukt.bsnet.se>.
30
 
31
 
 
32
 
from __future__ import division
33
2
 
34
3
import SocketServer
35
4
import socket
40
9
import gnutls.crypto
41
10
import gnutls.connection
42
11
import gnutls.errors
43
 
import gnutls.library.functions
44
 
import gnutls.library.constants
45
 
import gnutls.library.types
46
12
import ConfigParser
47
13
import sys
48
 
import re
49
 
import os
50
 
import signal
51
 
from sets import Set
52
 
import subprocess
53
 
import atexit
54
 
import stat
55
 
import logging
56
 
import logging.handlers
57
 
 
58
 
import dbus
59
 
import gobject
60
 
import avahi
61
 
from dbus.mainloop.glib import DBusGMainLoop
62
 
import ctypes
63
 
 
64
 
version = "1.0"
65
 
 
66
 
logger = logging.Logger('mandos')
67
 
syslogger = logging.handlers.SysLogHandler\
68
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
69
 
             address = "/dev/log")
70
 
syslogger.setFormatter(logging.Formatter\
71
 
                        ('Mandos: %(levelname)s: %(message)s'))
72
 
logger.addHandler(syslogger)
73
 
 
74
 
console = logging.StreamHandler()
75
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
76
 
                                       ' %(message)s'))
77
 
logger.addHandler(console)
78
 
 
79
 
class AvahiError(Exception):
80
 
    def __init__(self, value):
81
 
        self.value = value
82
 
    def __str__(self):
83
 
        return repr(self.value)
84
 
 
85
 
class AvahiServiceError(AvahiError):
86
 
    pass
87
 
 
88
 
class AvahiGroupError(AvahiError):
89
 
    pass
90
 
 
91
 
 
92
 
class AvahiService(object):
93
 
    """An Avahi (Zeroconf) service.
94
 
    Attributes:
95
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
96
 
               Used to optionally bind to the specified interface.
97
 
    name: string; Example: 'Mandos'
98
 
    type: string; Example: '_mandos._tcp'.
99
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
100
 
    port: integer; what port to announce
101
 
    TXT: list of strings; TXT record for the service
102
 
    domain: string; Domain to publish on, default to .local if empty.
103
 
    host: string; Host to publish records for, default is localhost
104
 
    max_renames: integer; maximum number of renames
105
 
    rename_count: integer; counter so we only rename after collisions
106
 
                  a sensible number of times
107
 
    """
108
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
109
 
                 type = None, port = None, TXT = None, domain = "",
110
 
                 host = "", max_renames = 32768):
111
 
        self.interface = interface
112
 
        self.name = name
113
 
        self.type = type
114
 
        self.port = port
115
 
        if TXT is None:
116
 
            self.TXT = []
117
 
        else:
118
 
            self.TXT = TXT
119
 
        self.domain = domain
120
 
        self.host = host
121
 
        self.rename_count = 0
122
 
        self.max_renames = max_renames
123
 
    def rename(self):
124
 
        """Derived from the Avahi example code"""
125
 
        if self.rename_count >= self.max_renames:
126
 
            logger.critical(u"No suitable service name found after %i"
127
 
                            u" retries, exiting.", rename_count)
128
 
            raise AvahiServiceError("Too many renames")
129
 
        self.name = server.GetAlternativeServiceName(self.name)
130
 
        logger.info(u"Changing name to %r ...", str(self.name))
131
 
        syslogger.setFormatter(logging.Formatter\
132
 
                               ('Mandos (%s): %%(levelname)s:'
133
 
                               ' %%(message)s' % self.name))
134
 
        self.remove()
135
 
        self.add()
136
 
        self.rename_count += 1
137
 
    def remove(self):
138
 
        """Derived from the Avahi example code"""
139
 
        if group is not None:
140
 
            group.Reset()
141
 
    def add(self):
142
 
        """Derived from the Avahi example code"""
143
 
        global group
144
 
        if group is None:
145
 
            group = dbus.Interface\
146
 
                    (bus.get_object(avahi.DBUS_NAME,
147
 
                                    server.EntryGroupNew()),
148
 
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
149
 
            group.connect_to_signal('StateChanged',
150
 
                                    entry_group_state_changed)
151
 
        logger.debug(u"Adding service '%s' of type '%s' ...",
152
 
                     service.name, service.type)
153
 
        group.AddService(
154
 
                self.interface,         # interface
155
 
                avahi.PROTO_INET6,      # protocol
156
 
                dbus.UInt32(0),         # flags
157
 
                self.name, self.type,
158
 
                self.domain, self.host,
159
 
                dbus.UInt16(self.port),
160
 
                avahi.string_array_to_txt_array(self.TXT))
161
 
        group.Commit()
162
 
 
163
 
# From the Avahi example code:
164
 
group = None                            # our entry group
165
 
# End of Avahi example code
166
 
 
167
14
 
168
15
class Client(object):
169
 
    """A representation of a client host served by this server.
170
 
    Attributes:
171
 
    name:      string; from the config file, used in log messages
172
 
    fingerprint: string (40 or 32 hexadecimal digits); used to
173
 
                 uniquely identify the client
174
 
    secret:    bytestring; sent verbatim (over TLS) to client
175
 
    host:      string; available for use by the checker command
176
 
    created:   datetime.datetime(); object creation, not client host
177
 
    last_checked_ok: datetime.datetime() or None if not yet checked OK
178
 
    timeout:   datetime.timedelta(); How long from last_checked_ok
179
 
                                     until this client is invalid
180
 
    interval:  datetime.timedelta(); How often to start a new checker
181
 
    stop_hook: If set, called by stop() as stop_hook(self)
182
 
    checker:   subprocess.Popen(); a running checker process used
183
 
                                   to see if the client lives.
184
 
                                   'None' if no process is running.
185
 
    checker_initiator_tag: a gobject event source tag, or None
186
 
    stop_initiator_tag:    - '' -
187
 
    checker_callback_tag:  - '' -
188
 
    checker_command: string; External command which is run to check if
189
 
                     client lives.  %() expansions are done at
190
 
                     runtime with vars(self) as dict, so that for
191
 
                     instance %(name)s can be used in the command.
192
 
    Private attibutes:
193
 
    _timeout: Real variable for 'timeout'
194
 
    _interval: Real variable for 'interval'
195
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
196
 
    _interval_milliseconds: - '' -
197
 
    """
198
 
    def _set_timeout(self, timeout):
199
 
        "Setter function for 'timeout' attribute"
200
 
        self._timeout = timeout
201
 
        self._timeout_milliseconds = ((self.timeout.days
202
 
                                       * 24 * 60 * 60 * 1000)
203
 
                                      + (self.timeout.seconds * 1000)
204
 
                                      + (self.timeout.microseconds
205
 
                                         // 1000))
206
 
    timeout = property(lambda self: self._timeout,
207
 
                       _set_timeout)
208
 
    del _set_timeout
209
 
    def _set_interval(self, interval):
210
 
        "Setter function for 'interval' attribute"
211
 
        self._interval = interval
212
 
        self._interval_milliseconds = ((self.interval.days
213
 
                                        * 24 * 60 * 60 * 1000)
214
 
                                       + (self.interval.seconds
215
 
                                          * 1000)
216
 
                                       + (self.interval.microseconds
217
 
                                          // 1000))
218
 
    interval = property(lambda self: self._interval,
219
 
                        _set_interval)
220
 
    del _set_interval
221
 
    def __init__(self, name = None, stop_hook=None, config={}):
222
 
        """Note: the 'checker' key in 'config' sets the
223
 
        'checker_command' attribute and *not* the 'checker'
224
 
        attribute."""
 
16
    def __init__(self, name=None, dn=None, password=None,
 
17
                 passfile=None, fqdn=None, timeout=None,
 
18
                 interval=-1):
225
19
        self.name = name
226
 
        logger.debug(u"Creating client %r", self.name)
227
 
        # Uppercase and remove spaces from fingerprint for later
228
 
        # comparison purposes with return value from the fingerprint()
229
 
        # function
230
 
        self.fingerprint = config["fingerprint"].upper()\
231
 
                           .replace(u" ", u"")
232
 
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
233
 
        if "secret" in config:
234
 
            self.secret = config["secret"].decode(u"base64")
235
 
        elif "secfile" in config:
236
 
            sf = open(config["secfile"])
237
 
            self.secret = sf.read()
238
 
            sf.close()
 
20
        self.dn = dn
 
21
        if password:
 
22
            self.password = password
 
23
        elif passfile:
 
24
            self.password = open(passfile).readall()
239
25
        else:
240
 
            raise TypeError(u"No secret or secfile for client %s"
241
 
                            % self.name)
242
 
        self.host = config.get("host", "")
 
26
            print "No Password or Passfile in client config file"
 
27
            # raise RuntimeError XXX
 
28
            self.password = "gazonk"
 
29
        self.fqdn = fqdn
243
30
        self.created = datetime.datetime.now()
244
 
        self.last_checked_ok = None
245
 
        self.timeout = string_to_delta(config["timeout"])
246
 
        self.interval = string_to_delta(config["interval"])
247
 
        self.stop_hook = stop_hook
248
 
        self.checker = None
249
 
        self.checker_initiator_tag = None
250
 
        self.stop_initiator_tag = None
251
 
        self.checker_callback_tag = None
252
 
        self.check_command = config["checker"]
253
 
    def start(self):
254
 
        """Start this client's checker and timeout hooks"""
255
 
        # Schedule a new checker to be started an 'interval' from now,
256
 
        # and every interval from then on.
257
 
        self.checker_initiator_tag = gobject.timeout_add\
258
 
                                     (self._interval_milliseconds,
259
 
                                      self.start_checker)
260
 
        # Also start a new checker *right now*.
261
 
        self.start_checker()
262
 
        # Schedule a stop() when 'timeout' has passed
263
 
        self.stop_initiator_tag = gobject.timeout_add\
264
 
                                  (self._timeout_milliseconds,
265
 
                                   self.stop)
266
 
    def stop(self):
267
 
        """Stop this client.
268
 
        The possibility that a client might be restarted is left open,
269
 
        but not currently used."""
270
 
        # If this client doesn't have a secret, it is already stopped.
271
 
        if hasattr(self, "secret") and self.secret:
272
 
            logger.info(u"Stopping client %s", self.name)
273
 
            self.secret = None
274
 
        else:
275
 
            return False
276
 
        if getattr(self, "stop_initiator_tag", False):
277
 
            gobject.source_remove(self.stop_initiator_tag)
278
 
            self.stop_initiator_tag = None
279
 
        if getattr(self, "checker_initiator_tag", False):
280
 
            gobject.source_remove(self.checker_initiator_tag)
281
 
            self.checker_initiator_tag = None
282
 
        self.stop_checker()
283
 
        if self.stop_hook:
284
 
            self.stop_hook(self)
285
 
        # Do not run this again if called by a gobject.timeout_add
286
 
        return False
287
 
    def __del__(self):
288
 
        self.stop_hook = None
289
 
        self.stop()
290
 
    def checker_callback(self, pid, condition):
291
 
        """The checker has completed, so take appropriate actions."""
292
 
        now = datetime.datetime.now()
293
 
        self.checker_callback_tag = None
294
 
        self.checker = None
295
 
        if os.WIFEXITED(condition) \
296
 
               and (os.WEXITSTATUS(condition) == 0):
297
 
            logger.info(u"Checker for %(name)s succeeded",
298
 
                        vars(self))
299
 
            self.last_checked_ok = now
300
 
            gobject.source_remove(self.stop_initiator_tag)
301
 
            self.stop_initiator_tag = gobject.timeout_add\
302
 
                                      (self._timeout_milliseconds,
303
 
                                       self.stop)
304
 
        elif not os.WIFEXITED(condition):
305
 
            logger.warning(u"Checker for %(name)s crashed?",
306
 
                           vars(self))
307
 
        else:
308
 
            logger.info(u"Checker for %(name)s failed",
309
 
                        vars(self))
310
 
    def start_checker(self):
311
 
        """Start a new checker subprocess if one is not running.
312
 
        If a checker already exists, leave it running and do
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.
322
 
        if self.checker is None:
323
 
            try:
324
 
                # In case check_command has exactly one % operator
325
 
                command = self.check_command % self.host
326
 
            except TypeError:
327
 
                # Escape attributes for the shell
328
 
                escaped_attrs = dict((key, re.escape(str(val)))
329
 
                                     for key, val in
330
 
                                     vars(self).iteritems())
331
 
                try:
332
 
                    command = self.check_command % escaped_attrs
333
 
                except TypeError, error:
334
 
                    logger.error(u'Could not format string "%s":'
335
 
                                 u' %s', self.check_command, error)
336
 
                    return True # Try again later
337
 
            try:
338
 
                logger.info(u"Starting checker %r for %s",
339
 
                            command, self.name)
340
 
                self.checker = subprocess.Popen(command,
341
 
                                                close_fds=True,
342
 
                                                shell=True, cwd="/")
343
 
                self.checker_callback_tag = gobject.child_watch_add\
344
 
                                            (self.checker.pid,
345
 
                                             self.checker_callback)
346
 
            except subprocess.OSError, error:
347
 
                logger.error(u"Failed to start subprocess: %s",
348
 
                             error)
349
 
        # Re-run this periodically if run by gobject.timeout_add
350
 
        return True
351
 
    def stop_checker(self):
352
 
        """Force the checker process, if any, to stop."""
353
 
        if self.checker_callback_tag:
354
 
            gobject.source_remove(self.checker_callback_tag)
355
 
            self.checker_callback_tag = None
356
 
        if getattr(self, "checker", None) is None:
357
 
            return
358
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
 
31
        self.last_seen = None
 
32
        if timeout is None:
 
33
            timeout = self.server.options.timeout
 
34
        self.timeout = timeout
 
35
        if interval == -1:
 
36
            interval = self.server.options.interval
 
37
        self.interval = interval
 
38
        self.next_check = datetime.datetime.now()
 
39
 
 
40
def server_bind(self):
 
41
    if self.options.interface:
 
42
        if not hasattr(socket, "SO_BINDTODEVICE"):
 
43
            # From /usr/include/asm-i486/socket.h
 
44
            socket.SO_BINDTODEVICE = 25
359
45
        try:
360
 
            os.kill(self.checker.pid, signal.SIGTERM)
361
 
            #os.sleep(0.5)
362
 
            #if self.checker.poll() is None:
363
 
            #    os.kill(self.checker.pid, signal.SIGKILL)
364
 
        except OSError, error:
365
 
            if error.errno != errno.ESRCH: # No such process
366
 
                raise
367
 
        self.checker = None
368
 
    def still_valid(self):
369
 
        """Has the timeout not yet passed for this client?"""
370
 
        now = datetime.datetime.now()
371
 
        if self.last_checked_ok is None:
372
 
            return now < (self.created + self.timeout)
373
 
        else:
374
 
            return now < (self.last_checked_ok + self.timeout)
375
 
 
376
 
 
377
 
def peer_certificate(session):
378
 
    "Return the peer's OpenPGP certificate as a bytestring"
379
 
    # If not an OpenPGP certificate...
380
 
    if gnutls.library.functions.gnutls_certificate_type_get\
381
 
            (session._c_object) \
382
 
           != gnutls.library.constants.GNUTLS_CRT_OPENPGP:
383
 
        # ...do the normal thing
384
 
        return session.peer_certificate
385
 
    list_size = ctypes.c_uint()
386
 
    cert_list = gnutls.library.functions.gnutls_certificate_get_peers\
387
 
        (session._c_object, ctypes.byref(list_size))
388
 
    if list_size.value == 0:
389
 
        return None
390
 
    cert = cert_list[0]
391
 
    return ctypes.string_at(cert.data, cert.size)
392
 
 
393
 
 
394
 
def fingerprint(openpgp):
395
 
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
396
 
    # New GnuTLS "datum" with the OpenPGP public key
397
 
    datum = gnutls.library.types.gnutls_datum_t\
398
 
        (ctypes.cast(ctypes.c_char_p(openpgp),
399
 
                     ctypes.POINTER(ctypes.c_ubyte)),
400
 
         ctypes.c_uint(len(openpgp)))
401
 
    # New empty GnuTLS certificate
402
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
403
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
404
 
        (ctypes.byref(crt))
405
 
    # Import the OpenPGP public key into the certificate
406
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
407
 
                    (crt, ctypes.byref(datum),
408
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
409
 
    # New buffer for the fingerprint
410
 
    buffer = ctypes.create_string_buffer(20)
411
 
    buffer_length = ctypes.c_size_t()
412
 
    # Get the fingerprint from the certificate into the buffer
413
 
    gnutls.library.functions.gnutls_openpgp_crt_get_fingerprint\
414
 
        (crt, ctypes.byref(buffer), ctypes.byref(buffer_length))
415
 
    # Deinit the certificate
416
 
    gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
417
 
    # Convert the buffer to a Python bytestring
418
 
    fpr = ctypes.string_at(buffer, buffer_length.value)
419
 
    # Convert the bytestring to hexadecimal notation
420
 
    hex_fpr = u''.join(u"%02X" % ord(char) for char in fpr)
421
 
    return hex_fpr
 
46
            self.socket.setsockopt(socket.SOL_SOCKET,
 
47
                                   socket.SO_BINDTODEVICE,
 
48
                                   self.options.interface)
 
49
        except socket.error, error:
 
50
            if error[0] == errno.EPERM:
 
51
                print "Warning: Denied permission to bind to interface", \
 
52
                      self.options.interface
 
53
            else:
 
54
                raise error
 
55
    return super(type(self), self).server_bind()
 
56
 
 
57
 
 
58
def init_with_options(self, *args, **kwargs):
 
59
    if "options" in kwargs:
 
60
        self.options = kwargs["options"]
 
61
        del kwargs["options"]
 
62
    if "clients" in kwargs:
 
63
        self.clients = kwargs["clients"]
 
64
        del kwargs["clients"]
 
65
    if "credentials" in kwargs:
 
66
        self.credentials = kwargs["credentials"]
 
67
        del kwargs["credentials"]
 
68
    return super(type(self), self).__init__(*args, **kwargs)
 
69
 
 
70
 
 
71
class udp_handler(SocketServer.DatagramRequestHandler, object):
 
72
    def handle(self):
 
73
        self.wfile.write("Polo")
 
74
        print "UDP request answered"
 
75
 
 
76
 
 
77
class IPv6_UDPServer(SocketServer.UDPServer, object):
 
78
    __init__ = init_with_options
 
79
    address_family = socket.AF_INET6
 
80
    allow_reuse_address = True
 
81
    server_bind = server_bind
 
82
    def verify_request(self, request, client_address):
 
83
        print "UDP request came"
 
84
        return request[0] == "Marco"
422
85
 
423
86
 
424
87
class tcp_handler(SocketServer.BaseRequestHandler, object):
425
 
    """A TCP request handler class.
426
 
    Instantiated by IPv6_TCPServer for each request to handle it.
427
 
    Note: This will run in its own forked process."""
428
 
    
429
88
    def handle(self):
430
 
        logger.info(u"TCP connection from: %s",
431
 
                     unicode(self.client_address))
432
 
        session = gnutls.connection.ClientSession\
433
 
                  (self.request, gnutls.connection.X509Credentials())
434
 
        
435
 
        line = self.request.makefile().readline()
436
 
        logger.debug(u"Protocol version: %r", line)
437
 
        try:
438
 
            if int(line.strip().split()[0]) > 1:
439
 
                raise RuntimeError
440
 
        except (ValueError, IndexError, RuntimeError), error:
441
 
            logger.error(u"Unknown protocol version: %s", error)
442
 
            return
443
 
        
444
 
        # Note: gnutls.connection.X509Credentials is really a generic
445
 
        # GnuTLS certificate credentials object so long as no X.509
446
 
        # keys are added to it.  Therefore, we can use it here despite
447
 
        # using OpenPGP certificates.
448
 
        
449
 
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
450
 
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
451
 
        #                "+DHE-DSS"))
452
 
        priority = "NORMAL"             # Fallback default, since this
453
 
                                        # MUST be set.
454
 
        if self.server.settings["priority"]:
455
 
            priority = self.server.settings["priority"]
456
 
        gnutls.library.functions.gnutls_priority_set_direct\
457
 
            (session._c_object, priority, None);
458
 
        
459
 
        try:
460
 
            session.handshake()
461
 
        except gnutls.errors.GNUTLSError, error:
462
 
            logger.warning(u"Handshake failed: %s", error)
463
 
            # Do not run session.bye() here: the session is not
464
 
            # established.  Just abandon the request.
465
 
            return
466
 
        try:
467
 
            fpr = fingerprint(peer_certificate(session))
468
 
        except (TypeError, gnutls.errors.GNUTLSError), error:
469
 
            logger.warning(u"Bad certificate: %s", error)
470
 
            session.bye()
471
 
            return
472
 
        logger.debug(u"Fingerprint: %s", fpr)
473
 
        client = None
474
 
        for c in self.server.clients:
475
 
            if c.fingerprint == fpr:
476
 
                client = c
477
 
                break
478
 
        if not client:
479
 
            logger.warning(u"Client not found for fingerprint: %s",
480
 
                           fpr)
481
 
            session.bye()
482
 
            return
483
 
        # Have to check if client.still_valid(), since it is possible
484
 
        # that the client timed out while establishing the GnuTLS
485
 
        # session.
486
 
        if not client.still_valid():
487
 
            logger.warning(u"Client %(name)s is invalid",
488
 
                           vars(client))
489
 
            session.bye()
490
 
            return
491
 
        sent_size = 0
492
 
        while sent_size < len(client.secret):
493
 
            sent = session.send(client.secret[sent_size:])
494
 
            logger.debug(u"Sent: %d, remaining: %d",
495
 
                         sent, len(client.secret)
496
 
                         - (sent_size + sent))
497
 
            sent_size += sent
 
89
        print "TCP request came"
 
90
        print "Request:", self.request
 
91
        print "Client Address:", self.client_address
 
92
        print "Server:", self.server
 
93
        session = gnutls.connection.ServerSession(self.request,
 
94
                                                  self.server.credentials)
 
95
        session.handshake()
 
96
        if session.peer_certificate:
 
97
            print "DN:", session.peer_certificate.subject
 
98
        try:
 
99
            session.verify_peer()
 
100
        except gnutls.errors.CertificateError, error:
 
101
            print "Verify failed", error
 
102
            session.bye()
 
103
            return
 
104
        try:
 
105
            session.send(dict((client.dn, client.password)
 
106
                              for client in self.server.clients)
 
107
                         [session.peer_certificate.subject])
 
108
        except KeyError:
 
109
            session.send("gazonk")
 
110
            # Log maybe? XXX
498
111
        session.bye()
499
112
 
500
 
 
501
113
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
502
 
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
503
 
    Attributes:
504
 
        settings:       Server settings
505
 
        clients:        Set() of Client objects
506
 
    """
 
114
    __init__ = init_with_options
507
115
    address_family = socket.AF_INET6
508
 
    def __init__(self, *args, **kwargs):
509
 
        if "settings" in kwargs:
510
 
            self.settings = kwargs["settings"]
511
 
            del kwargs["settings"]
512
 
        if "clients" in kwargs:
513
 
            self.clients = kwargs["clients"]
514
 
            del kwargs["clients"]
515
 
        return super(type(self), self).__init__(*args, **kwargs)
516
 
    def server_bind(self):
517
 
        """This overrides the normal server_bind() function
518
 
        to bind to an interface if one was specified, and also NOT to
519
 
        bind to an address or port if they were not specified."""
520
 
        if self.settings["interface"]:
521
 
            # 25 is from /usr/include/asm-i486/socket.h
522
 
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
523
 
            try:
524
 
                self.socket.setsockopt(socket.SOL_SOCKET,
525
 
                                       SO_BINDTODEVICE,
526
 
                                       self.settings["interface"])
527
 
            except socket.error, error:
528
 
                if error[0] == errno.EPERM:
529
 
                    logger.error(u"No permission to"
530
 
                                 u" bind to interface %s",
531
 
                                 self.settings["interface"])
532
 
                else:
533
 
                    raise error
534
 
        # Only bind(2) the socket if we really need to.
535
 
        if self.server_address[0] or self.server_address[1]:
536
 
            if not self.server_address[0]:
537
 
                in6addr_any = "::"
538
 
                self.server_address = (in6addr_any,
539
 
                                       self.server_address[1])
540
 
            elif not self.server_address[1]:
541
 
                self.server_address = (self.server_address[0],
542
 
                                       0)
543
 
#                 if self.settings["interface"]:
544
 
#                     self.server_address = (self.server_address[0],
545
 
#                                            0, # port
546
 
#                                            0, # flowinfo
547
 
#                                            if_nametoindex
548
 
#                                            (self.settings
549
 
#                                             ["interface"]))
550
 
            return super(type(self), self).server_bind()
551
 
 
 
116
    allow_reuse_address = True
 
117
    request_queue_size = 1024
 
118
    server_bind = server_bind
 
119
 
 
120
 
 
121
in6addr_any = "::"
 
122
 
 
123
cred = None
552
124
 
553
125
def string_to_delta(interval):
554
126
    """Parse a string and return a datetime.timedelta
583
155
        raise ValueError
584
156
    return delta
585
157
 
586
 
 
587
 
def server_state_changed(state):
588
 
    """Derived from the Avahi example code"""
589
 
    if state == avahi.SERVER_COLLISION:
590
 
        logger.error(u"Server name collision")
591
 
        service.remove()
592
 
    elif state == avahi.SERVER_RUNNING:
593
 
        service.add()
594
 
 
595
 
 
596
 
def entry_group_state_changed(state, error):
597
 
    """Derived from the Avahi example code"""
598
 
    logger.debug(u"state change: %i", state)
599
 
    
600
 
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
601
 
        logger.debug(u"Service established.")
602
 
    elif state == avahi.ENTRY_GROUP_COLLISION:
603
 
        logger.warning(u"Service name collision.")
604
 
        service.rename()
605
 
    elif state == avahi.ENTRY_GROUP_FAILURE:
606
 
        logger.critical(u"Error in group state changed %s",
607
 
                        unicode(error))
608
 
        raise AvahiGroupError("State changed: %s", str(error))
609
 
 
610
 
def if_nametoindex(interface):
611
 
    """Call the C function if_nametoindex(), or equivalent"""
612
 
    global if_nametoindex
613
 
    try:
614
 
        if "ctypes.util" not in sys.modules:
615
 
            import ctypes.util
616
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
617
 
            (ctypes.util.find_library("c")).if_nametoindex
618
 
    except (OSError, AttributeError):
619
 
        if "struct" not in sys.modules:
620
 
            import struct
621
 
        if "fcntl" not in sys.modules:
622
 
            import fcntl
623
 
        def if_nametoindex(interface):
624
 
            "Get an interface index the hard way, i.e. using fcntl()"
625
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
626
 
            s = socket.socket()
627
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
628
 
                                struct.pack("16s16x", interface))
629
 
            s.close()
630
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
631
 
            return interface_index
632
 
    return if_nametoindex(interface)
633
 
 
634
 
 
635
 
def daemon(nochdir = False, noclose = False):
636
 
    """See daemon(3).  Standard BSD Unix function.
637
 
    This should really exist as os.daemon, but it doesn't (yet)."""
638
 
    if os.fork():
639
 
        sys.exit()
640
 
    os.setsid()
641
 
    if not nochdir:
642
 
        os.chdir("/")
643
 
    if os.fork():
644
 
        sys.exit()
645
 
    if not noclose:
646
 
        # Close all standard open file descriptors
647
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
648
 
        if not stat.S_ISCHR(os.fstat(null).st_mode):
649
 
            raise OSError(errno.ENODEV,
650
 
                          "/dev/null not a character device")
651
 
        os.dup2(null, sys.stdin.fileno())
652
 
        os.dup2(null, sys.stdout.fileno())
653
 
        os.dup2(null, sys.stderr.fileno())
654
 
        if null > 2:
655
 
            os.close(null)
656
 
 
657
 
 
658
158
def main():
659
 
    global main_loop_started
660
 
    main_loop_started = False
661
 
    
662
 
    parser = OptionParser(version = "%%prog %s" % version)
 
159
    parser = OptionParser()
663
160
    parser.add_option("-i", "--interface", type="string",
664
 
                      metavar="IF", help="Bind to interface IF")
665
 
    parser.add_option("-a", "--address", type="string",
666
 
                      help="Address to listen for requests on")
667
 
    parser.add_option("-p", "--port", type="int",
 
161
                      default="eth0", metavar="IF",
 
162
                      help="Interface to bind to")
 
163
    parser.add_option("--cert", type="string", default="cert.pem",
 
164
                      metavar="FILE",
 
165
                      help="Public key certificate to use")
 
166
    parser.add_option("--key", type="string", default="key.pem",
 
167
                      metavar="FILE",
 
168
                      help="Private key to use")
 
169
    parser.add_option("--ca", type="string", default="ca.pem",
 
170
                      metavar="FILE",
 
171
                      help="Certificate Authority certificate to use")
 
172
    parser.add_option("--crl", type="string", default="crl.pem",
 
173
                      metavar="FILE",
 
174
                      help="Certificate Revokation List to use")
 
175
    parser.add_option("-p", "--port", type="int", default=49001,
668
176
                      help="Port number to receive requests on")
 
177
    parser.add_option("--dh", type="int", metavar="BITS",
 
178
                      help="DH group to use")
 
179
    parser.add_option("-t", "--timeout", type="string", # Parsed later
 
180
                      default="15m",
 
181
                      help="Amount of downtime allowed for clients")
 
182
    parser.add_option("--interval", type="string", # Parsed later
 
183
                      default="5m",
 
184
                      help="How often to check that a client is up")
669
185
    parser.add_option("--check", action="store_true", default=False,
670
186
                      help="Run self-test")
671
 
    parser.add_option("--debug", action="store_true",
672
 
                      help="Debug mode; run in foreground and log to"
673
 
                      " terminal")
674
 
    parser.add_option("--priority", type="string", help="GnuTLS"
675
 
                      " priority string (see GnuTLS documentation)")
676
 
    parser.add_option("--servicename", type="string", metavar="NAME",
677
 
                      help="Zeroconf service name")
678
 
    parser.add_option("--configdir", type="string",
679
 
                      default="/etc/mandos", metavar="DIR",
680
 
                      help="Directory to search for configuration"
681
 
                      " files")
682
187
    (options, args) = parser.parse_args()
683
 
    
 
188
 
684
189
    if options.check:
685
190
        import doctest
686
191
        doctest.testmod()
687
192
        sys.exit()
688
193
    
689
 
    # Default values for config file for server-global settings
690
 
    server_defaults = { "interface": "",
691
 
                        "address": "",
692
 
                        "port": "",
693
 
                        "debug": "False",
694
 
                        "priority":
695
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
696
 
                        "servicename": "Mandos",
697
 
                        }
698
 
    
699
 
    # Parse config file for server-global settings
700
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
701
 
    del server_defaults
702
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
703
 
    server_section = "server"
704
 
    # Convert the SafeConfigParser object to a dict
705
 
    server_settings = dict(server_config.items(server_section))
706
 
    # Use getboolean on the boolean config option
707
 
    server_settings["debug"] = server_config.getboolean\
708
 
                               (server_section, "debug")
709
 
    del server_config
710
 
    
711
 
    # Override the settings from the config file with command line
712
 
    # options, if set.
713
 
    for option in ("interface", "address", "port", "debug",
714
 
                   "priority", "servicename", "configdir"):
715
 
        value = getattr(options, option)
716
 
        if value is not None:
717
 
            server_settings[option] = value
718
 
    del options
719
 
    # Now we have our good server settings in "server_settings"
720
 
    
721
 
    debug = server_settings["debug"]
722
 
    
723
 
    if not debug:
724
 
        syslogger.setLevel(logging.WARNING)
725
 
        console.setLevel(logging.WARNING)
726
 
    
727
 
    if server_settings["servicename"] != "Mandos":
728
 
        syslogger.setFormatter(logging.Formatter\
729
 
                               ('Mandos (%s): %%(levelname)s:'
730
 
                                ' %%(message)s'
731
 
                                % server_settings["servicename"]))
732
 
    
733
 
    # Parse config file with clients
734
 
    client_defaults = { "timeout": "1h",
735
 
                        "interval": "5m",
736
 
                        "checker": "fping -q -- %%(host)s",
737
 
                        }
738
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
739
 
    client_config.read(os.path.join(server_settings["configdir"],
740
 
                                    "clients.conf"))
741
 
    
742
 
    global service
743
 
    service = AvahiService(name = server_settings["servicename"],
744
 
                           type = "_mandos._tcp", );
745
 
    if server_settings["interface"]:
746
 
        service.interface = if_nametoindex(server_settings["interface"])
747
 
    
748
 
    global main_loop
749
 
    global bus
750
 
    global server
751
 
    # From the Avahi example code
752
 
    DBusGMainLoop(set_as_default=True )
753
 
    main_loop = gobject.MainLoop()
754
 
    bus = dbus.SystemBus()
755
 
    server = dbus.Interface(
756
 
            bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
757
 
            avahi.DBUS_INTERFACE_SERVER )
758
 
    # End of Avahi example code
759
 
    
760
 
    clients = Set()
761
 
    def remove_from_clients(client):
762
 
        clients.remove(client)
763
 
        if not clients:
764
 
            logger.critical(u"No clients left, exiting")
765
 
            sys.exit()
766
 
    
767
 
    clients.update(Set(Client(name = section,
768
 
                              stop_hook = remove_from_clients,
769
 
                              config
770
 
                              = dict(client_config.items(section)))
771
 
                       for section in client_config.sections()))
772
 
    if not clients:
773
 
        logger.critical(u"No clients defined")
774
 
        sys.exit(1)
775
 
    
776
 
    if not debug:
777
 
        logger.removeHandler(console)
778
 
        daemon()
779
 
    
780
 
    pidfilename = "/var/run/mandos/mandos.pid"
781
 
    pid = os.getpid()
782
 
    try:
783
 
        pidfile = open(pidfilename, "w")
784
 
        pidfile.write(str(pid) + "\n")
785
 
        pidfile.close()
786
 
        del pidfile
787
 
    except IOError, err:
788
 
        logger.error(u"Could not write %s file with PID %d",
789
 
                     pidfilename, os.getpid())
790
 
    
791
 
    def cleanup():
792
 
        "Cleanup function; run on exit"
793
 
        global group
794
 
        # From the Avahi example code
795
 
        if not group is None:
796
 
            group.Free()
797
 
            group = None
798
 
        # End of Avahi example code
799
 
        
800
 
        while clients:
801
 
            client = clients.pop()
802
 
            client.stop_hook = None
803
 
            client.stop()
804
 
    
805
 
    atexit.register(cleanup)
806
 
    
807
 
    if not debug:
808
 
        signal.signal(signal.SIGINT, signal.SIG_IGN)
809
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
810
 
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
811
 
    
812
 
    for client in clients:
813
 
        client.start()
814
 
    
815
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
816
 
                                 server_settings["port"]),
 
194
    # Parse the time arguments
 
195
    try:
 
196
        options.timeout = string_to_delta(options.timeout)
 
197
    except ValueError:
 
198
        parser.error("option --timeout: Unparseable time")
 
199
    
 
200
    try:
 
201
        options.interval = string_to_delta(options.interval)
 
202
    except ValueError:
 
203
        parser.error("option --interval: Unparseable time")
 
204
    
 
205
    cert = gnutls.crypto.X509Certificate(open(options.cert).read())
 
206
    key = gnutls.crypto.X509PrivateKey(open(options.key).read())
 
207
    ca = gnutls.crypto.X509Certificate(open(options.ca).read())
 
208
    crl = gnutls.crypto.X509CRL(open(options.crl).read())
 
209
    cred = gnutls.connection.X509Credentials(cert, key, [ca], [crl])
 
210
    
 
211
    # Parse config file
 
212
    defaults = {}
 
213
    client_config_object = ConfigParser.SafeConfigParser(defaults)
 
214
    client_config_object.read("mandos-clients.conf")
 
215
    clients = [Client(name=section,
 
216
                      **(dict(client_config_object.items(section))))
 
217
               for section in client_config_object.sections()]
 
218
    
 
219
    udp_server = IPv6_UDPServer((in6addr_any, options.port),
 
220
                                udp_handler,
 
221
                                options=options)
 
222
    
 
223
    tcp_server = IPv6_TCPServer((in6addr_any, options.port),
817
224
                                tcp_handler,
818
 
                                settings=server_settings,
819
 
                                clients=clients)
820
 
    # Find out what port we got
821
 
    service.port = tcp_server.socket.getsockname()[1]
822
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
823
 
                u" scope_id %d" % tcp_server.socket.getsockname())
824
 
    
825
 
    #service.interface = tcp_server.socket.getsockname()[3]
826
 
    
827
 
    try:
828
 
        # From the Avahi example code
829
 
        server.connect_to_signal("StateChanged", server_state_changed)
830
 
        try:
831
 
            server_state_changed(server.GetState())
832
 
        except dbus.exceptions.DBusException, error:
833
 
            logger.critical(u"DBusException: %s", error)
834
 
            sys.exit(1)
835
 
        # End of Avahi example code
836
 
        
837
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
838
 
                             lambda *args, **kwargs:
839
 
                             tcp_server.handle_request\
840
 
                             (*args[2:], **kwargs) or True)
841
 
        
842
 
        logger.debug(u"Starting main loop")
843
 
        main_loop_started = True
844
 
        main_loop.run()
845
 
    except AvahiError, error:
846
 
        logger.critical(u"AvahiError: %s" + unicode(error))
847
 
        sys.exit(1)
848
 
    except KeyboardInterrupt:
849
 
        if debug:
850
 
            print
851
 
 
852
 
if __name__ == '__main__':
 
225
                                options=options,
 
226
                                clients=clients,
 
227
                                credentials=cred)
 
228
    
 
229
    while True:
 
230
        in_, out, err = select.select((udp_server,
 
231
                                       tcp_server), (), ())
 
232
        for server in in_:
 
233
            server.handle_request()
 
234
 
 
235
 
 
236
if __name__ == "__main__":
853
237
    main()
 
238