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  • Committer: Teddy Hogeborn
  • Date: 2008-01-30 17:28:18 UTC
  • Revision ID: teddy@fukt.bsnet.se-20080130172818-fnrq2xmtg1wa8wo2
* client.cpp (main): Get t_old early since it is used on error exits.

* server.py (Client.checker): New attribute.
  (Client.check_action, Client.start_checker, Client.stop_checker,
  Client.fileno, Client.next_stop, Client.still_valid,
  Client.it_is_time_to_check): New methods.
  (Client.handle_request): Alias to "check_action".
  (main): Stop all started checkers on exit.  Exit cleanly on keyboard
  interrupt.

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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
14
import re
49
15
import os
50
16
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
17
 
168
18
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."""
 
19
    def __init__(self, name=None, options=None, dn=None,
 
20
                 password=None, passfile=None, fqdn=None,
 
21
                 timeout=None, interval=-1):
225
22
        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()
 
23
        self.dn = dn
 
24
        if password:
 
25
            self.password = password
 
26
        elif passfile:
 
27
            self.password = open(passfile).readall()
239
28
        else:
240
 
            raise TypeError(u"No secret or secfile for client %s"
241
 
                            % self.name)
242
 
        self.host = config.get("host", "")
 
29
            print "No Password or Passfile in client config file"
 
30
            # raise RuntimeError XXX
 
31
            self.password = "gazonk"
 
32
        self.fqdn = fqdn                # string
243
33
        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
 
34
        self.last_seen = None           # datetime.datetime()
 
35
        if timeout is None:
 
36
            timeout = options.timeout
 
37
        self.timeout = timeout          # datetime.timedelta()
 
38
        if interval == -1:
 
39
            interval = options.interval
 
40
        self.interval = interval        # datetime.timedelta()
 
41
        self.next_check = datetime.datetime.now() # datetime.datetime()
 
42
        self.checker = None             # or a subprocess.Popen()
 
43
    def check_action(self, now=None):
 
44
        """The checker said something and might have completed.
 
45
        Check if is has, and take appropriate actions."""
 
46
        if self.checker.poll() is None:
 
47
            # False alarm, no result yet
 
48
            #self.checker.read()
 
49
            return
 
50
        if now is None:
 
51
            now = datetime.datetime.now()
 
52
        if self.checker.returncode == 0:
 
53
            self.last_seen = now
 
54
        while self.next_check <= now:
 
55
            self.next_check += self.interval
 
56
    handle_request = check_action
 
57
    def start_checker(self):
282
58
        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
 
59
        try:
 
60
            self.checker = subprocess.Popen("sleep 1; fping -q -- %s"
 
61
                                            % re.escape(self.fqdn),
 
62
                                            stdout=subprocess.PIPE,
 
63
                                            close_fds=True,
 
64
                                            shell=True, cwd="/")
 
65
        except subprocess.OSError, e:
 
66
            print "Failed to start subprocess:", e
 
67
    def stop_checker(self):
 
68
        if self.checker is None:
 
69
            return
 
70
        os.kill(self.checker.pid, signal.SIGTERM)
 
71
        if self.checker.poll() is None:
 
72
            os.kill(self.checker.pid, signal.SIGKILL)
294
73
        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.
 
74
    __del__ = stop_checker
 
75
    def fileno(self):
322
76
        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())
 
77
            return None
 
78
        return self.checker.stdout.fileno()
 
79
    def next_stop(self):
 
80
        """The time when something must be done about this client"""
 
81
        return min(self.last_seen + self.timeout, self.next_check)
 
82
    def still_valid(self, now=None):
 
83
        """Has this client's timeout not passed?"""
 
84
        if now is None:
 
85
            now = datetime.datetime.now()
 
86
        return now < (self.last_seen + timeout)
 
87
    def it_is_time_to_check(self, now=None):
 
88
        if now is None:
 
89
            now = datetime.datetime.now()
 
90
        return self.next_check <= now
 
91
 
 
92
 
 
93
class server_metaclass(type):
 
94
    "Common behavior for the UDP and TCP server classes"
 
95
    def __new__(cls, name, bases, attrs):
 
96
        attrs["address_family"] = socket.AF_INET6
 
97
        attrs["allow_reuse_address"] = True
 
98
        def server_bind(self):
 
99
            if self.options.interface:
 
100
                if not hasattr(socket, "SO_BINDTODEVICE"):
 
101
                    # From /usr/include/asm-i486/socket.h
 
102
                    socket.SO_BINDTODEVICE = 25
331
103
                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))
359
 
        try:
360
 
            os.kill(self.checker.pid, signal.SIGTERM)
361
 
            #os.sleep(0.5)
362
 
            #if self.checker.poll() is None:
363
 
            #    os.kill(self.checker.pid, signal.SIGKILL)
364
 
        except OSError, error:
365
 
            if error.errno != errno.ESRCH: # No such process
366
 
                raise
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
 
104
                    self.socket.setsockopt(socket.SOL_SOCKET,
 
105
                                           socket.SO_BINDTODEVICE,
 
106
                                           self.options.interface)
 
107
                except socket.error, error:
 
108
                    if error[0] == errno.EPERM:
 
109
                        print "Warning: No permission to bind to interface", \
 
110
                              self.options.interface
 
111
                    else:
 
112
                        raise error
 
113
            return super(type(self), self).server_bind()
 
114
        attrs["server_bind"] = server_bind
 
115
        def init(self, *args, **kwargs):
 
116
            if "options" in kwargs:
 
117
                self.options = kwargs["options"]
 
118
                del kwargs["options"]
 
119
            if "clients" in kwargs:
 
120
                self.clients = kwargs["clients"]
 
121
                del kwargs["clients"]
 
122
            if "credentials" in kwargs:
 
123
                self.credentials = kwargs["credentials"]
 
124
                del kwargs["credentials"]
 
125
            return super(type(self), self).__init__(*args, **kwargs)
 
126
        attrs["__init__"] = init
 
127
        return type.__new__(cls, name, bases, attrs)
 
128
 
 
129
 
 
130
class udp_handler(SocketServer.DatagramRequestHandler, object):
 
131
    def handle(self):
 
132
        self.wfile.write("Polo")
 
133
        print "UDP request answered"
 
134
 
 
135
 
 
136
class IPv6_UDPServer(SocketServer.UDPServer, object):
 
137
    __metaclass__ = server_metaclass
 
138
    def verify_request(self, request, client_address):
 
139
        print "UDP request came"
 
140
        return request[0] == "Marco"
422
141
 
423
142
 
424
143
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
144
    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
 
145
        print "TCP request came"
 
146
        print "Request:", self.request
 
147
        print "Client Address:", self.client_address
 
148
        print "Server:", self.server
 
149
        session = gnutls.connection.ServerSession(self.request,
 
150
                                                  self.server.credentials)
 
151
        session.handshake()
 
152
        if session.peer_certificate:
 
153
            print "DN:", session.peer_certificate.subject
 
154
        try:
 
155
            session.verify_peer()
 
156
        except gnutls.errors.CertificateError, error:
 
157
            print "Verify failed", error
 
158
            session.bye()
 
159
            return
 
160
        try:
 
161
            session.send(dict((client.dn, client.password)
 
162
                              for client in self.server.clients)
 
163
                         [session.peer_certificate.subject])
 
164
        except KeyError:
 
165
            session.send("gazonk")
 
166
            # Log maybe? XXX
498
167
        session.bye()
499
168
 
500
169
 
501
170
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
 
    """
507
 
    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
 
 
 
171
    __metaclass__ = server_metaclass
 
172
    request_queue_size = 1024
 
173
 
 
174
 
 
175
in6addr_any = "::"
552
176
 
553
177
def string_to_delta(interval):
554
178
    """Parse a string and return a datetime.timedelta
584
208
    return delta
585
209
 
586
210
 
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
211
def main():
659
 
    global main_loop_started
660
 
    main_loop_started = False
661
 
    
662
 
    parser = OptionParser(version = "%%prog %s" % version)
 
212
    parser = OptionParser()
663
213
    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",
 
214
                      default="eth0", metavar="IF",
 
215
                      help="Interface to bind to")
 
216
    parser.add_option("--cert", type="string", default="cert.pem",
 
217
                      metavar="FILE",
 
218
                      help="Public key certificate to use")
 
219
    parser.add_option("--key", type="string", default="key.pem",
 
220
                      metavar="FILE",
 
221
                      help="Private key to use")
 
222
    parser.add_option("--ca", type="string", default="ca.pem",
 
223
                      metavar="FILE",
 
224
                      help="Certificate Authority certificate to use")
 
225
    parser.add_option("--crl", type="string", default="crl.pem",
 
226
                      metavar="FILE",
 
227
                      help="Certificate Revokation List to use")
 
228
    parser.add_option("-p", "--port", type="int", default=49001,
668
229
                      help="Port number to receive requests on")
 
230
    parser.add_option("--dh", type="int", metavar="BITS",
 
231
                      help="DH group to use")
 
232
    parser.add_option("-t", "--timeout", type="string", # Parsed later
 
233
                      default="15m",
 
234
                      help="Amount of downtime allowed for clients")
 
235
    parser.add_option("--interval", type="string", # Parsed later
 
236
                      default="5m",
 
237
                      help="How often to check that a client is up")
669
238
    parser.add_option("--check", action="store_true", default=False,
670
239
                      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
240
    (options, args) = parser.parse_args()
683
 
    
 
241
 
684
242
    if options.check:
685
243
        import doctest
686
244
        doctest.testmod()
687
245
        sys.exit()
688
246
    
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
 
    # Convert the SafeConfigParser object to a dict
704
 
    server_settings = server_config.defaults()
705
 
    # Use getboolean on the boolean config option
706
 
    server_settings["debug"] = server_config.getboolean\
707
 
                               ("DEFAULT", "debug")
708
 
    del server_config
709
 
    
710
 
    # Override the settings from the config file with command line
711
 
    # options, if set.
712
 
    for option in ("interface", "address", "port", "debug",
713
 
                   "priority", "servicename", "configdir"):
714
 
        value = getattr(options, option)
715
 
        if value is not None:
716
 
            server_settings[option] = value
717
 
    del options
718
 
    # Now we have our good server settings in "server_settings"
719
 
    
720
 
    debug = server_settings["debug"]
721
 
    
722
 
    if not debug:
723
 
        syslogger.setLevel(logging.WARNING)
724
 
        console.setLevel(logging.WARNING)
725
 
    
726
 
    if server_settings["servicename"] != "Mandos":
727
 
        syslogger.setFormatter(logging.Formatter\
728
 
                               ('Mandos (%s): %%(levelname)s:'
729
 
                                ' %%(message)s'
730
 
                                % server_settings["servicename"]))
731
 
    
732
 
    # Parse config file with clients
733
 
    client_defaults = { "timeout": "1h",
734
 
                        "interval": "5m",
735
 
                        "checker": "fping -q -- %%(host)s",
736
 
                        }
737
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
738
 
    client_config.read(os.path.join(server_settings["configdir"],
739
 
                                    "clients.conf"))
740
 
    
741
 
    global service
742
 
    service = AvahiService(name = server_settings["servicename"],
743
 
                           type = "_mandos._tcp", );
744
 
    if server_settings["interface"]:
745
 
        service.interface = if_nametoindex(server_settings["interface"])
746
 
    
747
 
    global main_loop
748
 
    global bus
749
 
    global server
750
 
    # From the Avahi example code
751
 
    DBusGMainLoop(set_as_default=True )
752
 
    main_loop = gobject.MainLoop()
753
 
    bus = dbus.SystemBus()
754
 
    server = dbus.Interface(
755
 
            bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
756
 
            avahi.DBUS_INTERFACE_SERVER )
757
 
    # End of Avahi example code
758
 
    
759
 
    clients = Set()
760
 
    def remove_from_clients(client):
761
 
        clients.remove(client)
762
 
        if not clients:
763
 
            logger.critical(u"No clients left, exiting")
764
 
            sys.exit()
765
 
    
766
 
    clients.update(Set(Client(name = section,
767
 
                              stop_hook = remove_from_clients,
768
 
                              config
769
 
                              = dict(client_config.items(section)))
770
 
                       for section in client_config.sections()))
771
 
    if not clients:
772
 
        logger.critical(u"No clients defined")
773
 
        sys.exit(1)
774
 
    
775
 
    if not debug:
776
 
        logger.removeHandler(console)
777
 
        daemon()
778
 
    
779
 
    pidfilename = "/var/run/mandos/mandos.pid"
780
 
    pid = os.getpid()
781
 
    try:
782
 
        pidfile = open(pidfilename, "w")
783
 
        pidfile.write(str(pid) + "\n")
784
 
        pidfile.close()
785
 
        del pidfile
786
 
    except IOError, err:
787
 
        logger.error(u"Could not write %s file with PID %d",
788
 
                     pidfilename, os.getpid())
789
 
    
790
 
    def cleanup():
791
 
        "Cleanup function; run on exit"
792
 
        global group
793
 
        # From the Avahi example code
794
 
        if not group is None:
795
 
            group.Free()
796
 
            group = None
797
 
        # End of Avahi example code
798
 
        
799
 
        while clients:
800
 
            client = clients.pop()
801
 
            client.stop_hook = None
802
 
            client.stop()
803
 
    
804
 
    atexit.register(cleanup)
805
 
    
806
 
    if not debug:
807
 
        signal.signal(signal.SIGINT, signal.SIG_IGN)
808
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
809
 
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
810
 
    
 
247
    # Parse the time arguments
 
248
    try:
 
249
        options.timeout = string_to_delta(options.timeout)
 
250
    except ValueError:
 
251
        parser.error("option --timeout: Unparseable time")
 
252
    
 
253
    try:
 
254
        options.interval = string_to_delta(options.interval)
 
255
    except ValueError:
 
256
        parser.error("option --interval: Unparseable time")
 
257
    
 
258
    cert = gnutls.crypto.X509Certificate(open(options.cert).read())
 
259
    key = gnutls.crypto.X509PrivateKey(open(options.key).read())
 
260
    ca = gnutls.crypto.X509Certificate(open(options.ca).read())
 
261
    crl = gnutls.crypto.X509CRL(open(options.crl).read())
 
262
    cred = gnutls.connection.X509Credentials(cert, key, [ca], [crl])
 
263
    
 
264
    # Parse config file
 
265
    defaults = {}
 
266
    client_config_object = ConfigParser.SafeConfigParser(defaults)
 
267
    client_config_object.read("mandos-clients.conf")
 
268
    clients = [Client(name=section, options=options,
 
269
                      **(dict(client_config_object.items(section))))
 
270
               for section in client_config_object.sections()]
 
271
    
 
272
    udp_server = IPv6_UDPServer((in6addr_any, options.port),
 
273
                                udp_handler,
 
274
                                options=options)
 
275
    
 
276
    tcp_server = IPv6_TCPServer((in6addr_any, options.port),
 
277
                                tcp_handler,
 
278
                                options=options,
 
279
                                clients=clients,
 
280
                                credentials=cred)
 
281
    
 
282
    while True:
 
283
        try:
 
284
            input, out, err = select.select((udp_server,
 
285
                                             tcp_server), (), ())
 
286
            if not input:
 
287
                pass
 
288
            else:
 
289
                for obj in input:
 
290
                    obj.handle_request()
 
291
        except KeyboardInterrupt:
 
292
            break
 
293
    
 
294
    # Cleanup here
811
295
    for client in clients:
812
 
        client.start()
813
 
    
814
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
815
 
                                 server_settings["port"]),
816
 
                                tcp_handler,
817
 
                                settings=server_settings,
818
 
                                clients=clients)
819
 
    # Find out what port we got
820
 
    service.port = tcp_server.socket.getsockname()[1]
821
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
822
 
                u" scope_id %d" % tcp_server.socket.getsockname())
823
 
    
824
 
    #service.interface = tcp_server.socket.getsockname()[3]
825
 
    
826
 
    try:
827
 
        # From the Avahi example code
828
 
        server.connect_to_signal("StateChanged", server_state_changed)
829
 
        try:
830
 
            server_state_changed(server.GetState())
831
 
        except dbus.exceptions.DBusException, error:
832
 
            logger.critical(u"DBusException: %s", error)
833
 
            sys.exit(1)
834
 
        # End of Avahi example code
835
 
        
836
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
837
 
                             lambda *args, **kwargs:
838
 
                             tcp_server.handle_request\
839
 
                             (*args[2:], **kwargs) or True)
840
 
        
841
 
        logger.debug(u"Starting main loop")
842
 
        main_loop_started = True
843
 
        main_loop.run()
844
 
    except AvahiError, error:
845
 
        logger.critical(u"AvahiError: %s" + unicode(error))
846
 
        sys.exit(1)
847
 
    except KeyboardInterrupt:
848
 
        if debug:
849
 
            print
850
 
 
851
 
if __name__ == '__main__':
 
296
        client.stop_checker()
 
297
 
 
298
 
 
299
if __name__ == "__main__":
852
300
    main()
 
301