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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
 
 
3
import SocketServer
 
4
import socket
 
5
import select
 
6
from optparse import OptionParser
 
7
import datetime
 
8
import errno
 
9
import gnutls.crypto
 
10
import gnutls.connection
 
11
import gnutls.errors
 
12
import ConfigParser
 
13
import sys
 
14
import re
 
15
import os
 
16
import signal
 
17
 
 
18
class Client(object):
 
19
    def __init__(self, name=None, options=None, dn=None,
 
20
                 password=None, passfile=None, fqdn=None,
 
21
                 timeout=None, interval=-1):
 
22
        self.name = name
 
23
        self.dn = dn
 
24
        if password:
 
25
            self.password = password
 
26
        elif passfile:
 
27
            self.password = open(passfile).readall()
 
28
        else:
 
29
            print "No Password or Passfile in client config file"
 
30
            # raise RuntimeError XXX
 
31
            self.password = "gazonk"
 
32
        self.fqdn = fqdn                # string
 
33
        self.created = datetime.datetime.now()
 
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):
 
58
        self.stop_checker()
 
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)
 
73
        self.checker = None
 
74
    __del__ = stop_checker
 
75
    def fileno(self):
 
76
        if self.checker is None:
 
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
 
103
                try:
 
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"
 
141
 
 
142
 
 
143
class tcp_handler(SocketServer.BaseRequestHandler, object):
 
144
    def handle(self):
 
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
 
167
        session.bye()
 
168
 
 
169
 
 
170
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
 
171
    __metaclass__ = server_metaclass
 
172
    request_queue_size = 1024
 
173
 
 
174
 
 
175
in6addr_any = "::"
 
176
 
 
177
def string_to_delta(interval):
 
178
    """Parse a string and return a datetime.timedelta
 
179
 
 
180
    >>> string_to_delta('7d')
 
181
    datetime.timedelta(7)
 
182
    >>> string_to_delta('60s')
 
183
    datetime.timedelta(0, 60)
 
184
    >>> string_to_delta('60m')
 
185
    datetime.timedelta(0, 3600)
 
186
    >>> string_to_delta('24h')
 
187
    datetime.timedelta(1)
 
188
    >>> string_to_delta(u'1w')
 
189
    datetime.timedelta(7)
 
190
    """
 
191
    try:
 
192
        suffix=unicode(interval[-1])
 
193
        value=int(interval[:-1])
 
194
        if suffix == u"d":
 
195
            delta = datetime.timedelta(value)
 
196
        elif suffix == u"s":
 
197
            delta = datetime.timedelta(0, value)
 
198
        elif suffix == u"m":
 
199
            delta = datetime.timedelta(0, 0, 0, 0, value)
 
200
        elif suffix == u"h":
 
201
            delta = datetime.timedelta(0, 0, 0, 0, 0, value)
 
202
        elif suffix == u"w":
 
203
            delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
 
204
        else:
 
205
            raise ValueError
 
206
    except (ValueError, IndexError):
 
207
        raise ValueError
 
208
    return delta
 
209
 
 
210
 
 
211
def main():
 
212
    parser = OptionParser()
 
213
    parser.add_option("-i", "--interface", type="string",
 
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,
 
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")
 
238
    parser.add_option("--check", action="store_true", default=False,
 
239
                      help="Run self-test")
 
240
    (options, args) = parser.parse_args()
 
241
 
 
242
    if options.check:
 
243
        import doctest
 
244
        doctest.testmod()
 
245
        sys.exit()
 
246
    
 
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
 
295
    for client in clients:
 
296
        client.stop_checker()
 
297
 
 
298
 
 
299
if __name__ == "__main__":
 
300
    main()
 
301