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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
 
 
65
 
logger = logging.Logger('mandos')
66
 
syslogger = logging.handlers.SysLogHandler\
67
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
68
 
             address = "/dev/log")
69
 
syslogger.setFormatter(logging.Formatter\
70
 
                        ('Mandos: %(levelname)s: %(message)s'))
71
 
logger.addHandler(syslogger)
72
 
 
73
 
 
74
 
class AvahiError(Exception):
75
 
    def __init__(self, value):
76
 
        self.value = value
77
 
    def __str__(self):
78
 
        return repr(self.value)
79
 
 
80
 
class AvahiServiceError(AvahiError):
81
 
    pass
82
 
 
83
 
class AvahiGroupError(AvahiError):
84
 
    pass
85
 
 
86
 
 
87
 
class AvahiService(object):
88
 
    """An Avahi (Zeroconf) service.
89
 
    Attributes:
90
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
91
 
               Used to optionally bind to the specified interface.
92
 
    name: string; Example: 'Mandos'
93
 
    type: string; Example: '_mandos._tcp'.
94
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
95
 
    port: integer; what port to announce
96
 
    TXT: list of strings; TXT record for the service
97
 
    domain: string; Domain to publish on, default to .local if empty.
98
 
    host: string; Host to publish records for, default is localhost
99
 
    max_renames: integer; maximum number of renames
100
 
    rename_count: integer; counter so we only rename after collisions
101
 
                  a sensible number of times
102
 
    """
103
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
104
 
                 type = None, port = None, TXT = None, domain = "",
105
 
                 host = "", max_renames = 32768):
106
 
        self.interface = interface
107
 
        self.name = name
108
 
        self.type = type
109
 
        self.port = port
110
 
        if TXT is None:
111
 
            self.TXT = []
112
 
        else:
113
 
            self.TXT = TXT
114
 
        self.domain = domain
115
 
        self.host = host
116
 
        self.rename_count = 0
117
 
    def rename(self):
118
 
        """Derived from the Avahi example code"""
119
 
        if self.rename_count >= self.max_renames:
120
 
            logger.critical(u"No suitable service name found after %i"
121
 
                            u" retries, exiting.", rename_count)
122
 
            raise AvahiServiceError("Too many renames")
123
 
        name = server.GetAlternativeServiceName(name)
124
 
        logger.error(u"Changing name to %r ...", name)
125
 
        syslogger.setFormatter(logging.Formatter\
126
 
                               ('Mandos (%s): %%(levelname)s:'
127
 
                               ' %%(message)s' % name))
128
 
        self.remove()
129
 
        self.add()
130
 
        self.rename_count += 1
131
 
    def remove(self):
132
 
        """Derived from the Avahi example code"""
133
 
        if group is not None:
134
 
            group.Reset()
135
 
    def add(self):
136
 
        """Derived from the Avahi example code"""
137
 
        global group
138
 
        if group is None:
139
 
            group = dbus.Interface\
140
 
                    (bus.get_object(avahi.DBUS_NAME,
141
 
                                    server.EntryGroupNew()),
142
 
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
143
 
            group.connect_to_signal('StateChanged',
144
 
                                    entry_group_state_changed)
145
 
        logger.debug(u"Adding service '%s' of type '%s' ...",
146
 
                     service.name, service.type)
147
 
        group.AddService(
148
 
                self.interface,         # interface
149
 
                avahi.PROTO_INET6,      # protocol
150
 
                dbus.UInt32(0),         # flags
151
 
                self.name, self.type,
152
 
                self.domain, self.host,
153
 
                dbus.UInt16(self.port),
154
 
                avahi.string_array_to_txt_array(self.TXT))
155
 
        group.Commit()
156
 
 
157
 
# From the Avahi example code:
158
 
group = None                            # our entry group
159
 
# End of Avahi example code
160
 
 
161
17
 
162
18
class Client(object):
163
 
    """A representation of a client host served by this server.
164
 
    Attributes:
165
 
    name:      string; from the config file, used in log messages
166
 
    fingerprint: string (40 or 32 hexadecimal digits); used to
167
 
                 uniquely identify the client
168
 
    secret:    bytestring; sent verbatim (over TLS) to client
169
 
    host:      string; available for use by the checker command
170
 
    created:   datetime.datetime(); object creation, not client host
171
 
    last_checked_ok: datetime.datetime() or None if not yet checked OK
172
 
    timeout:   datetime.timedelta(); How long from last_checked_ok
173
 
                                     until this client is invalid
174
 
    interval:  datetime.timedelta(); How often to start a new checker
175
 
    stop_hook: If set, called by stop() as stop_hook(self)
176
 
    checker:   subprocess.Popen(); a running checker process used
177
 
                                   to see if the client lives.
178
 
                                   'None' if no process is running.
179
 
    checker_initiator_tag: a gobject event source tag, or None
180
 
    stop_initiator_tag:    - '' -
181
 
    checker_callback_tag:  - '' -
182
 
    checker_command: string; External command which is run to check if
183
 
                     client lives.  %() expansions are done at
184
 
                     runtime with vars(self) as dict, so that for
185
 
                     instance %(name)s can be used in the command.
186
 
    Private attibutes:
187
 
    _timeout: Real variable for 'timeout'
188
 
    _interval: Real variable for 'interval'
189
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
190
 
    _interval_milliseconds: - '' -
191
 
    """
192
 
    def _set_timeout(self, timeout):
193
 
        "Setter function for 'timeout' attribute"
194
 
        self._timeout = timeout
195
 
        self._timeout_milliseconds = ((self.timeout.days
196
 
                                       * 24 * 60 * 60 * 1000)
197
 
                                      + (self.timeout.seconds * 1000)
198
 
                                      + (self.timeout.microseconds
199
 
                                         // 1000))
200
 
    timeout = property(lambda self: self._timeout,
201
 
                       _set_timeout)
202
 
    del _set_timeout
203
 
    def _set_interval(self, interval):
204
 
        "Setter function for 'interval' attribute"
205
 
        self._interval = interval
206
 
        self._interval_milliseconds = ((self.interval.days
207
 
                                        * 24 * 60 * 60 * 1000)
208
 
                                       + (self.interval.seconds
209
 
                                          * 1000)
210
 
                                       + (self.interval.microseconds
211
 
                                          // 1000))
212
 
    interval = property(lambda self: self._interval,
213
 
                        _set_interval)
214
 
    del _set_interval
215
 
    def __init__(self, name = None, stop_hook=None, config={}):
216
 
        """Note: the 'checker' key in 'config' sets the
217
 
        'checker_command' attribute and *not* the 'checker'
218
 
        attribute."""
 
19
    def __init__(self, name=None, options=None, dn=None,
 
20
                 password=None, passfile=None, fqdn=None,
 
21
                 timeout=None, interval=-1):
219
22
        self.name = name
220
 
        logger.debug(u"Creating client %r", self.name)
221
 
        # Uppercase and remove spaces from fingerprint for later
222
 
        # comparison purposes with return value from the fingerprint()
223
 
        # function
224
 
        self.fingerprint = config["fingerprint"].upper()\
225
 
                           .replace(u" ", u"")
226
 
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
227
 
        if "secret" in config:
228
 
            self.secret = config["secret"].decode(u"base64")
229
 
        elif "secfile" in config:
230
 
            sf = open(config["secfile"])
231
 
            self.secret = sf.read()
232
 
            sf.close()
 
23
        self.dn = dn
 
24
        if password:
 
25
            self.password = password
 
26
        elif passfile:
 
27
            self.password = open(passfile).readall()
233
28
        else:
234
 
            raise TypeError(u"No secret or secfile for client %s"
235
 
                            % self.name)
236
 
        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
237
33
        self.created = datetime.datetime.now()
238
 
        self.last_checked_ok = None
239
 
        self.timeout = string_to_delta(config["timeout"])
240
 
        self.interval = string_to_delta(config["interval"])
241
 
        self.stop_hook = stop_hook
242
 
        self.checker = None
243
 
        self.checker_initiator_tag = None
244
 
        self.stop_initiator_tag = None
245
 
        self.checker_callback_tag = None
246
 
        self.check_command = config["checker"]
247
 
    def start(self):
248
 
        """Start this client's checker and timeout hooks"""
249
 
        # Schedule a new checker to be started an 'interval' from now,
250
 
        # and every interval from then on.
251
 
        self.checker_initiator_tag = gobject.timeout_add\
252
 
                                     (self._interval_milliseconds,
253
 
                                      self.start_checker)
254
 
        # Also start a new checker *right now*.
255
 
        self.start_checker()
256
 
        # Schedule a stop() when 'timeout' has passed
257
 
        self.stop_initiator_tag = gobject.timeout_add\
258
 
                                  (self._timeout_milliseconds,
259
 
                                   self.stop)
260
 
    def stop(self):
261
 
        """Stop this client.
262
 
        The possibility that a client might be restarted is left open,
263
 
        but not currently used."""
264
 
        # If this client doesn't have a secret, it is already stopped.
265
 
        if hasattr(self, "secret") and self.secret:
266
 
            logger.info(u"Stopping client %s", self.name)
267
 
            self.secret = None
268
 
        else:
269
 
            return False
270
 
        if getattr(self, "stop_initiator_tag", False):
271
 
            gobject.source_remove(self.stop_initiator_tag)
272
 
            self.stop_initiator_tag = None
273
 
        if getattr(self, "checker_initiator_tag", False):
274
 
            gobject.source_remove(self.checker_initiator_tag)
275
 
            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):
276
58
        self.stop_checker()
277
 
        if self.stop_hook:
278
 
            self.stop_hook(self)
279
 
        # Do not run this again if called by a gobject.timeout_add
280
 
        return False
281
 
    def __del__(self):
282
 
        self.stop_hook = None
283
 
        self.stop()
284
 
    def checker_callback(self, pid, condition):
285
 
        """The checker has completed, so take appropriate actions."""
286
 
        now = datetime.datetime.now()
287
 
        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)
288
73
        self.checker = None
289
 
        if os.WIFEXITED(condition) \
290
 
               and (os.WEXITSTATUS(condition) == 0):
291
 
            logger.info(u"Checker for %(name)s succeeded",
292
 
                        vars(self))
293
 
            self.last_checked_ok = now
294
 
            gobject.source_remove(self.stop_initiator_tag)
295
 
            self.stop_initiator_tag = gobject.timeout_add\
296
 
                                      (self._timeout_milliseconds,
297
 
                                       self.stop)
298
 
        elif not os.WIFEXITED(condition):
299
 
            logger.warning(u"Checker for %(name)s crashed?",
300
 
                           vars(self))
301
 
        else:
302
 
            logger.info(u"Checker for %(name)s failed",
303
 
                        vars(self))
304
 
    def start_checker(self):
305
 
        """Start a new checker subprocess if one is not running.
306
 
        If a checker already exists, leave it running and do
307
 
        nothing."""
308
 
        # The reason for not killing a running checker is that if we
309
 
        # did that, then if a checker (for some reason) started
310
 
        # running slowly and taking more than 'interval' time, the
311
 
        # client would inevitably timeout, since no checker would get
312
 
        # a chance to run to completion.  If we instead leave running
313
 
        # checkers alone, the checker would have to take more time
314
 
        # than 'timeout' for the client to be declared invalid, which
315
 
        # is as it should be.
 
74
    __del__ = stop_checker
 
75
    def fileno(self):
316
76
        if self.checker is None:
317
 
            try:
318
 
                # In case check_command has exactly one % operator
319
 
                command = self.check_command % self.host
320
 
            except TypeError:
321
 
                # Escape attributes for the shell
322
 
                escaped_attrs = dict((key, re.escape(str(val)))
323
 
                                     for key, val in
324
 
                                     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
325
103
                try:
326
 
                    command = self.check_command % escaped_attrs
327
 
                except TypeError, error:
328
 
                    logger.error(u'Could not format string "%s":'
329
 
                                 u' %s', self.check_command, error)
330
 
                    return True # Try again later
331
 
            try:
332
 
                logger.info(u"Starting checker %r for %s",
333
 
                            command, self.name)
334
 
                self.checker = subprocess.Popen(command,
335
 
                                                close_fds=True,
336
 
                                                shell=True, cwd="/")
337
 
                self.checker_callback_tag = gobject.child_watch_add\
338
 
                                            (self.checker.pid,
339
 
                                             self.checker_callback)
340
 
            except subprocess.OSError, error:
341
 
                logger.error(u"Failed to start subprocess: %s",
342
 
                             error)
343
 
        # Re-run this periodically if run by gobject.timeout_add
344
 
        return True
345
 
    def stop_checker(self):
346
 
        """Force the checker process, if any, to stop."""
347
 
        if self.checker_callback_tag:
348
 
            gobject.source_remove(self.checker_callback_tag)
349
 
            self.checker_callback_tag = None
350
 
        if getattr(self, "checker", None) is None:
351
 
            return
352
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
353
 
        try:
354
 
            os.kill(self.checker.pid, signal.SIGTERM)
355
 
            #os.sleep(0.5)
356
 
            #if self.checker.poll() is None:
357
 
            #    os.kill(self.checker.pid, signal.SIGKILL)
358
 
        except OSError, error:
359
 
            if error.errno != errno.ESRCH: # No such process
360
 
                raise
361
 
        self.checker = None
362
 
    def still_valid(self):
363
 
        """Has the timeout not yet passed for this client?"""
364
 
        now = datetime.datetime.now()
365
 
        if self.last_checked_ok is None:
366
 
            return now < (self.created + self.timeout)
367
 
        else:
368
 
            return now < (self.last_checked_ok + self.timeout)
369
 
 
370
 
 
371
 
def peer_certificate(session):
372
 
    "Return the peer's OpenPGP certificate as a bytestring"
373
 
    # If not an OpenPGP certificate...
374
 
    if gnutls.library.functions.gnutls_certificate_type_get\
375
 
            (session._c_object) \
376
 
           != gnutls.library.constants.GNUTLS_CRT_OPENPGP:
377
 
        # ...do the normal thing
378
 
        return session.peer_certificate
379
 
    list_size = ctypes.c_uint()
380
 
    cert_list = gnutls.library.functions.gnutls_certificate_get_peers\
381
 
        (session._c_object, ctypes.byref(list_size))
382
 
    if list_size.value == 0:
383
 
        return None
384
 
    cert = cert_list[0]
385
 
    return ctypes.string_at(cert.data, cert.size)
386
 
 
387
 
 
388
 
def fingerprint(openpgp):
389
 
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
390
 
    # New GnuTLS "datum" with the OpenPGP public key
391
 
    datum = gnutls.library.types.gnutls_datum_t\
392
 
        (ctypes.cast(ctypes.c_char_p(openpgp),
393
 
                     ctypes.POINTER(ctypes.c_ubyte)),
394
 
         ctypes.c_uint(len(openpgp)))
395
 
    # New empty GnuTLS certificate
396
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
397
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
398
 
        (ctypes.byref(crt))
399
 
    # Import the OpenPGP public key into the certificate
400
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
401
 
                    (crt, ctypes.byref(datum),
402
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
403
 
    # New buffer for the fingerprint
404
 
    buffer = ctypes.create_string_buffer(20)
405
 
    buffer_length = ctypes.c_size_t()
406
 
    # Get the fingerprint from the certificate into the buffer
407
 
    gnutls.library.functions.gnutls_openpgp_crt_get_fingerprint\
408
 
        (crt, ctypes.byref(buffer), ctypes.byref(buffer_length))
409
 
    # Deinit the certificate
410
 
    gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
411
 
    # Convert the buffer to a Python bytestring
412
 
    fpr = ctypes.string_at(buffer, buffer_length.value)
413
 
    # Convert the bytestring to hexadecimal notation
414
 
    hex_fpr = u''.join(u"%02X" % ord(char) for char in fpr)
415
 
    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"
416
141
 
417
142
 
418
143
class tcp_handler(SocketServer.BaseRequestHandler, object):
419
 
    """A TCP request handler class.
420
 
    Instantiated by IPv6_TCPServer for each request to handle it.
421
 
    Note: This will run in its own forked process."""
422
 
    
423
144
    def handle(self):
424
 
        logger.info(u"TCP connection from: %s",
425
 
                     unicode(self.client_address))
426
 
        session = gnutls.connection.ClientSession\
427
 
                  (self.request, gnutls.connection.X509Credentials())
428
 
        
429
 
        line = self.request.makefile().readline()
430
 
        logger.debug(u"Protocol version: %r", line)
431
 
        try:
432
 
            if int(line.strip().split()[0]) > 1:
433
 
                raise RuntimeError
434
 
        except (ValueError, IndexError, RuntimeError), error:
435
 
            logger.error(u"Unknown protocol version: %s", error)
436
 
            return
437
 
        
438
 
        # Note: gnutls.connection.X509Credentials is really a generic
439
 
        # GnuTLS certificate credentials object so long as no X.509
440
 
        # keys are added to it.  Therefore, we can use it here despite
441
 
        # using OpenPGP certificates.
442
 
        
443
 
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
444
 
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
445
 
        #                "+DHE-DSS"))
446
 
        priority = "NORMAL"             # Fallback default, since this
447
 
                                        # MUST be set.
448
 
        if self.server.settings["priority"]:
449
 
            priority = self.server.settings["priority"]
450
 
        gnutls.library.functions.gnutls_priority_set_direct\
451
 
            (session._c_object, priority, None);
452
 
        
453
 
        try:
454
 
            session.handshake()
455
 
        except gnutls.errors.GNUTLSError, error:
456
 
            logger.warning(u"Handshake failed: %s", error)
457
 
            # Do not run session.bye() here: the session is not
458
 
            # established.  Just abandon the request.
459
 
            return
460
 
        try:
461
 
            fpr = fingerprint(peer_certificate(session))
462
 
        except (TypeError, gnutls.errors.GNUTLSError), error:
463
 
            logger.warning(u"Bad certificate: %s", error)
464
 
            session.bye()
465
 
            return
466
 
        logger.debug(u"Fingerprint: %s", fpr)
467
 
        client = None
468
 
        for c in self.server.clients:
469
 
            if c.fingerprint == fpr:
470
 
                client = c
471
 
                break
472
 
        if not client:
473
 
            logger.warning(u"Client not found for fingerprint: %s",
474
 
                           fpr)
475
 
            session.bye()
476
 
            return
477
 
        # Have to check if client.still_valid(), since it is possible
478
 
        # that the client timed out while establishing the GnuTLS
479
 
        # session.
480
 
        if not client.still_valid():
481
 
            logger.warning(u"Client %(name)s is invalid",
482
 
                           vars(client))
483
 
            session.bye()
484
 
            return
485
 
        sent_size = 0
486
 
        while sent_size < len(client.secret):
487
 
            sent = session.send(client.secret[sent_size:])
488
 
            logger.debug(u"Sent: %d, remaining: %d",
489
 
                         sent, len(client.secret)
490
 
                         - (sent_size + sent))
491
 
            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
492
167
        session.bye()
493
168
 
494
169
 
495
170
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
496
 
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
497
 
    Attributes:
498
 
        settings:       Server settings
499
 
        clients:        Set() of Client objects
500
 
    """
501
 
    address_family = socket.AF_INET6
502
 
    def __init__(self, *args, **kwargs):
503
 
        if "settings" in kwargs:
504
 
            self.settings = kwargs["settings"]
505
 
            del kwargs["settings"]
506
 
        if "clients" in kwargs:
507
 
            self.clients = kwargs["clients"]
508
 
            del kwargs["clients"]
509
 
        return super(type(self), self).__init__(*args, **kwargs)
510
 
    def server_bind(self):
511
 
        """This overrides the normal server_bind() function
512
 
        to bind to an interface if one was specified, and also NOT to
513
 
        bind to an address or port if they were not specified."""
514
 
        if self.settings["interface"]:
515
 
            # 25 is from /usr/include/asm-i486/socket.h
516
 
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
517
 
            try:
518
 
                self.socket.setsockopt(socket.SOL_SOCKET,
519
 
                                       SO_BINDTODEVICE,
520
 
                                       self.settings["interface"])
521
 
            except socket.error, error:
522
 
                if error[0] == errno.EPERM:
523
 
                    logger.error(u"No permission to"
524
 
                                 u" bind to interface %s",
525
 
                                 self.settings["interface"])
526
 
                else:
527
 
                    raise error
528
 
        # Only bind(2) the socket if we really need to.
529
 
        if self.server_address[0] or self.server_address[1]:
530
 
            if not self.server_address[0]:
531
 
                in6addr_any = "::"
532
 
                self.server_address = (in6addr_any,
533
 
                                       self.server_address[1])
534
 
            elif not self.server_address[1]:
535
 
                self.server_address = (self.server_address[0],
536
 
                                       0)
537
 
#                 if self.settings["interface"]:
538
 
#                     self.server_address = (self.server_address[0],
539
 
#                                            0, # port
540
 
#                                            0, # flowinfo
541
 
#                                            if_nametoindex
542
 
#                                            (self.settings
543
 
#                                             ["interface"]))
544
 
            return super(type(self), self).server_bind()
545
 
 
 
171
    __metaclass__ = server_metaclass
 
172
    request_queue_size = 1024
 
173
 
 
174
 
 
175
in6addr_any = "::"
546
176
 
547
177
def string_to_delta(interval):
548
178
    """Parse a string and return a datetime.timedelta
578
208
    return delta
579
209
 
580
210
 
581
 
def server_state_changed(state):
582
 
    """Derived from the Avahi example code"""
583
 
    if state == avahi.SERVER_COLLISION:
584
 
        logger.error(u"Server name collision")
585
 
        service.remove()
586
 
    elif state == avahi.SERVER_RUNNING:
587
 
        service.add()
588
 
 
589
 
 
590
 
def entry_group_state_changed(state, error):
591
 
    """Derived from the Avahi example code"""
592
 
    logger.debug(u"state change: %i", state)
593
 
    
594
 
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
595
 
        logger.debug(u"Service established.")
596
 
    elif state == avahi.ENTRY_GROUP_COLLISION:
597
 
        logger.warning(u"Service name collision.")
598
 
        service.rename()
599
 
    elif state == avahi.ENTRY_GROUP_FAILURE:
600
 
        logger.critical(u"Error in group state changed %s",
601
 
                        unicode(error))
602
 
        raise AvahiGroupError("State changed: %s", str(error))
603
 
 
604
 
def if_nametoindex(interface):
605
 
    """Call the C function if_nametoindex(), or equivalent"""
606
 
    global if_nametoindex
607
 
    try:
608
 
        if "ctypes.util" not in sys.modules:
609
 
            import ctypes.util
610
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
611
 
            (ctypes.util.find_library("c")).if_nametoindex
612
 
    except (OSError, AttributeError):
613
 
        if "struct" not in sys.modules:
614
 
            import struct
615
 
        if "fcntl" not in sys.modules:
616
 
            import fcntl
617
 
        def if_nametoindex(interface):
618
 
            "Get an interface index the hard way, i.e. using fcntl()"
619
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
620
 
            s = socket.socket()
621
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
622
 
                                struct.pack("16s16x", interface))
623
 
            s.close()
624
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
625
 
            return interface_index
626
 
    return if_nametoindex(interface)
627
 
 
628
 
 
629
 
def daemon(nochdir = False, noclose = False):
630
 
    """See daemon(3).  Standard BSD Unix function.
631
 
    This should really exist as os.daemon, but it doesn't (yet)."""
632
 
    if os.fork():
633
 
        sys.exit()
634
 
    os.setsid()
635
 
    if not nochdir:
636
 
        os.chdir("/")
637
 
    if os.fork():
638
 
        sys.exit()
639
 
    if not noclose:
640
 
        # Close all standard open file descriptors
641
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
642
 
        if not stat.S_ISCHR(os.fstat(null).st_mode):
643
 
            raise OSError(errno.ENODEV,
644
 
                          "/dev/null not a character device")
645
 
        os.dup2(null, sys.stdin.fileno())
646
 
        os.dup2(null, sys.stdout.fileno())
647
 
        os.dup2(null, sys.stderr.fileno())
648
 
        if null > 2:
649
 
            os.close(null)
650
 
 
651
 
 
652
211
def main():
653
 
    global main_loop_started
654
 
    main_loop_started = False
655
 
    
656
212
    parser = OptionParser()
657
213
    parser.add_option("-i", "--interface", type="string",
658
 
                      metavar="IF", help="Bind to interface IF")
659
 
    parser.add_option("-a", "--address", type="string",
660
 
                      help="Address to listen for requests on")
661
 
    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,
662
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")
663
238
    parser.add_option("--check", action="store_true", default=False,
664
239
                      help="Run self-test")
665
 
    parser.add_option("--debug", action="store_true",
666
 
                      help="Debug mode; run in foreground and log to"
667
 
                      " terminal")
668
 
    parser.add_option("--priority", type="string", help="GnuTLS"
669
 
                      " priority string (see GnuTLS documentation)")
670
 
    parser.add_option("--servicename", type="string", metavar="NAME",
671
 
                      help="Zeroconf service name")
672
 
    parser.add_option("--configdir", type="string",
673
 
                      default="/etc/mandos", metavar="DIR",
674
 
                      help="Directory to search for configuration"
675
 
                      " files")
676
240
    (options, args) = parser.parse_args()
677
 
    
 
241
 
678
242
    if options.check:
679
243
        import doctest
680
244
        doctest.testmod()
681
245
        sys.exit()
682
246
    
683
 
    # Default values for config file for server-global settings
684
 
    server_defaults = { "interface": "",
685
 
                        "address": "",
686
 
                        "port": "",
687
 
                        "debug": "False",
688
 
                        "priority":
689
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
690
 
                        "servicename": "Mandos",
691
 
                        }
692
 
    
693
 
    # Parse config file for server-global settings
694
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
695
 
    del server_defaults
696
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
697
 
    server_section = "server"
698
 
    # Convert the SafeConfigParser object to a dict
699
 
    server_settings = dict(server_config.items(server_section))
700
 
    # Use getboolean on the boolean config option
701
 
    server_settings["debug"] = server_config.getboolean\
702
 
                               (server_section, "debug")
703
 
    del server_config
704
 
    
705
 
    # Override the settings from the config file with command line
706
 
    # options, if set.
707
 
    for option in ("interface", "address", "port", "debug",
708
 
                   "priority", "servicename", "configdir"):
709
 
        value = getattr(options, option)
710
 
        if value is not None:
711
 
            server_settings[option] = value
712
 
    del options
713
 
    # Now we have our good server settings in "server_settings"
714
 
    
715
 
    debug = server_settings["debug"]
716
 
    
717
 
    if not debug:
718
 
        syslogger.setLevel(logging.WARNING)
719
 
    
720
 
    if server_settings["servicename"] != "Mandos":
721
 
        syslogger.setFormatter(logging.Formatter\
722
 
                               ('Mandos (%s): %%(levelname)s:'
723
 
                                ' %%(message)s'
724
 
                                % server_settings["servicename"]))
725
 
    
726
 
    # Parse config file with clients
727
 
    client_defaults = { "timeout": "1h",
728
 
                        "interval": "5m",
729
 
                        "checker": "fping -q -- %%(host)s",
730
 
                        }
731
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
732
 
    client_config.read(os.path.join(server_settings["configdir"],
733
 
                                    "clients.conf"))
734
 
    
735
 
    global service
736
 
    service = AvahiService(name = server_settings["servicename"],
737
 
                           type = "_mandos._tcp", );
738
 
    if server_settings["interface"]:
739
 
        service.interface = if_nametoindex(server_settings["interface"])
740
 
    
741
 
    global main_loop
742
 
    global bus
743
 
    global server
744
 
    # From the Avahi example code
745
 
    DBusGMainLoop(set_as_default=True )
746
 
    main_loop = gobject.MainLoop()
747
 
    bus = dbus.SystemBus()
748
 
    server = dbus.Interface(
749
 
            bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
750
 
            avahi.DBUS_INTERFACE_SERVER )
751
 
    # End of Avahi example code
752
 
    
753
 
    if debug:
754
 
        console = logging.StreamHandler()
755
 
        # console.setLevel(logging.DEBUG)
756
 
        console.setFormatter(logging.Formatter\
757
 
                             ('%(levelname)s: %(message)s'))
758
 
        logger.addHandler(console)
759
 
        del console
760
 
    
761
 
    clients = Set()
762
 
    def remove_from_clients(client):
763
 
        clients.remove(client)
764
 
        if not clients:
765
 
            logger.critical(u"No clients left, exiting")
766
 
            sys.exit()
767
 
    
768
 
    clients.update(Set(Client(name = section,
769
 
                              stop_hook = remove_from_clients,
770
 
                              config
771
 
                              = dict(client_config.items(section)))
772
 
                       for section in client_config.sections()))
773
 
    if not clients:
774
 
        logger.critical(u"No clients defined")
775
 
        sys.exit(1)
776
 
    
777
 
    if not debug:
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
 
    
 
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
812
295
    for client in clients:
813
 
        client.start()
814
 
    
815
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
816
 
                                 server_settings["port"]),
817
 
                                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__':
 
296
        client.stop_checker()
 
297
 
 
298
 
 
299
if __name__ == "__main__":
853
300
    main()
 
301