/mandos/trunk

#!/usr/bin/python

import SocketServer

import socket

import select

from optparse import OptionParser

import datetime

import errno

import gnutls.crypto

import gnutls.connection

import gnutls.errors

import ConfigParser

import sys

class Client(object):

    def __init__(self, name=None, options=None, dn=None,

                 password=None, passfile=None, fqdn=None,

                 timeout=None, interval=-1):

        self.name = name

        self.dn = dn

        if password:

            self.password = password

        elif passfile:

            self.password = open(passfile).readall()

        else:

            print "No Password or Passfile in client config file"

            # raise RuntimeError XXX

            self.password = "gazonk"

        self.fqdn = fqdn

        self.created = datetime.datetime.now()

        self.last_seen = None

        if timeout is None:

            timeout = options.timeout

        self.timeout = timeout

        if interval == -1:

            interval = options.interval

        self.interval = interval

        self.next_check = datetime.datetime.now()

class server_metaclass(type):

    "Common behavior for the UDP and TCP server classes"

    def __new__(cls, name, bases, attrs):

        attrs["address_family"] = socket.AF_INET6

        attrs["allow_reuse_address"] = True

        def server_bind(self):

            if self.options.interface:

                if not hasattr(socket, "SO_BINDTODEVICE"):

                    # From /usr/include/asm-i486/socket.h

                    socket.SO_BINDTODEVICE = 25

                try:

                    self.socket.setsockopt(socket.SOL_SOCKET,

                                           socket.SO_BINDTODEVICE,

                                           self.options.interface)

                except socket.error, error:

                    if error[0] == errno.EPERM:

                        print "Warning: No permission to bind to interface", \

                              self.options.interface

                    else:

                        raise error

            return super(type(self), self).server_bind()

        attrs["server_bind"] = server_bind

        def init(self, *args, **kwargs):

            if "options" in kwargs:

                self.options = kwargs["options"]

                del kwargs["options"]

            if "clients" in kwargs:

                self.clients = kwargs["clients"]

                del kwargs["clients"]

            if "credentials" in kwargs:

                self.credentials = kwargs["credentials"]

                del kwargs["credentials"]

            return super(type(self), self).__init__(*args, **kwargs)

        attrs["__init__"] = init

        return type.__new__(cls, name, bases, attrs)

class udp_handler(SocketServer.DatagramRequestHandler, object):

    def handle(self):

        self.wfile.write("Polo")

        print "UDP request answered"

class IPv6_UDPServer(SocketServer.UDPServer, object):

    __metaclass__ = server_metaclass

    def verify_request(self, request, client_address):

        print "UDP request came"

        return request[0] == "Marco"

class tcp_handler(SocketServer.BaseRequestHandler, object):

    def handle(self):

        print "TCP request came"

        print "Request:", self.request

        print "Client Address:", self.client_address

        print "Server:", self.server

        session = gnutls.connection.ServerSession(self.request,

                                                  self.server.credentials)

        session.handshake()

        if session.peer_certificate:

            print "DN:", session.peer_certificate.subject

        try:

            session.verify_peer()

        except gnutls.errors.CertificateError, error:

            print "Verify failed", error

            session.bye()

            return

        try:

            session.send(dict((client.dn, client.password)

                              for client in self.server.clients)

                         [session.peer_certificate.subject])

        except KeyError:

            session.send("gazonk")

            # Log maybe? XXX

        session.bye()

class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):

    __metaclass__ = server_metaclass

    request_queue_size = 1024

in6addr_any = "::"

def string_to_delta(interval):

    """Parse a string and return a datetime.timedelta

    >>> string_to_delta('7d')

    datetime.timedelta(7)

    >>> string_to_delta('60s')

    datetime.timedelta(0, 60)

    >>> string_to_delta('60m')

    datetime.timedelta(0, 3600)

    >>> string_to_delta('24h')

    datetime.timedelta(1)

    >>> string_to_delta(u'1w')

    datetime.timedelta(7)

    """

    try:

        suffix=unicode(interval[-1])

        value=int(interval[:-1])

        if suffix == u"d":

            delta = datetime.timedelta(value)

        elif suffix == u"s":

            delta = datetime.timedelta(0, value)

        elif suffix == u"m":

            delta = datetime.timedelta(0, 0, 0, 0, value)

        elif suffix == u"h":

            delta = datetime.timedelta(0, 0, 0, 0, 0, value)

        elif suffix == u"w":

            delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)

        else:

            raise ValueError

    except (ValueError, IndexError):

        raise ValueError

    return delta

def main():

    parser = OptionParser()

    parser.add_option("-i", "--interface", type="string",

                      default="eth0", metavar="IF",

                      help="Interface to bind to")

    parser.add_option("--cert", type="string", default="cert.pem",

                      metavar="FILE",

                      help="Public key certificate to use")

    parser.add_option("--key", type="string", default="key.pem",

                      metavar="FILE",

                      help="Private key to use")

    parser.add_option("--ca", type="string", default="ca.pem",

                      metavar="FILE",

                      help="Certificate Authority certificate to use")

    parser.add_option("--crl", type="string", default="crl.pem",

                      metavar="FILE",

                      help="Certificate Revokation List to use")

    parser.add_option("-p", "--port", type="int", default=49001,

                      help="Port number to receive requests on")

    parser.add_option("--dh", type="int", metavar="BITS",

                      help="DH group to use")

    parser.add_option("-t", "--timeout", type="string", # Parsed later

                      default="15m",

                      help="Amount of downtime allowed for clients")

    parser.add_option("--interval", type="string", # Parsed later

                      default="5m",

                      help="How often to check that a client is up")

    parser.add_option("--check", action="store_true", default=False,

                      help="Run self-test")

    (options, args) = parser.parse_args()

    if options.check:

        import doctest

        doctest.testmod()

        sys.exit()

    # Parse the time arguments

    try:

        options.timeout = string_to_delta(options.timeout)

    except ValueError:

        parser.error("option --timeout: Unparseable time")

    try:

        options.interval = string_to_delta(options.interval)

    except ValueError:

        parser.error("option --interval: Unparseable time")

    cert = gnutls.crypto.X509Certificate(open(options.cert).read())

    key = gnutls.crypto.X509PrivateKey(open(options.key).read())

    ca = gnutls.crypto.X509Certificate(open(options.ca).read())

    crl = gnutls.crypto.X509CRL(open(options.crl).read())

    cred = gnutls.connection.X509Credentials(cert, key, [ca], [crl])

    # Parse config file

    defaults = {}

    client_config_object = ConfigParser.SafeConfigParser(defaults)

    client_config_object.read("mandos-clients.conf")

    clients = [Client(name=section, options=options,

                      **(dict(client_config_object.items(section))))

               for section in client_config_object.sections()]

    udp_server = IPv6_UDPServer((in6addr_any, options.port),

                                udp_handler,

                                options=options)

    tcp_server = IPv6_TCPServer((in6addr_any, options.port),

                                tcp_handler,

                                options=options,

                                clients=clients,

                                credentials=cred)

    while True:

        in_, out, err = select.select((udp_server,

                                       tcp_server), (), ())

        for server in in_:

            server.handle_request()

if __name__ == "__main__":

    main()