/mandos/trunk : revision 491

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#!/usr/bin/python

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# -*- mode: python; coding: utf-8 -*-

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#

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# Mandos server - give out binary blobs to connecting clients.

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#

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# This program is partly derived from an example program for an Avahi

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# service publisher, downloaded from

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# <http://avahi.org/wiki/PythonPublishExample>. This includes the

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# methods "add", "remove", "server_state_changed",

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# "entry_group_state_changed", "cleanup", and "activate" in the

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# "AvahiService" class, and some lines in "main".

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#

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# Everything else is

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#

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# This program is free software: you can redistribute it and/or modify

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# it under the terms of the GNU General Public License as published by

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# the Free Software Foundation, either version 3 of the License, or

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# (at your option) any later version.

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#

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# This program is distributed in the hope that it will be useful,

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# but WITHOUT ANY WARRANTY; without even the implied warranty of

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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

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# GNU General Public License for more details.

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#

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# You should have received a copy of the GNU General Public License

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# along with this program. If not, see

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# <http://www.gnu.org/licenses/>.

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#

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# Contact the authors at <mandos@fukt.bsnet.se>.

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#

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from __future__ import (division, absolute_import, print_function,

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unicode_literals)

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import SocketServer as socketserver

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import socket

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import argparse

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import datetime

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import errno

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import gnutls.crypto

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import gnutls.connection

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import gnutls.errors

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import gnutls.library.functions

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import gnutls.library.constants

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import gnutls.library.types

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import ConfigParser as configparser

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import sys

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import re

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import os

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import signal

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import subprocess

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import atexit

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import stat

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import logging

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import logging.handlers

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import pwd

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import contextlib

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import struct

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import fcntl

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import functools

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import cPickle as pickle

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import multiprocessing

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import dbus

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import dbus.service

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import gobject

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import avahi

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from dbus.mainloop.glib import DBusGMainLoop

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import ctypes

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import ctypes.util

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import xml.dom.minidom

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import inspect

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try:

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SO_BINDTODEVICE = socket.SO_BINDTODEVICE

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except AttributeError:

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try:

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from IN import SO_BINDTODEVICE

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except ImportError:

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SO_BINDTODEVICE = None

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version = "1.3.1"

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#logger = logging.getLogger('mandos')

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logger = logging.Logger('mandos')

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syslogger = (logging.handlers.SysLogHandler

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(facility = logging.handlers.SysLogHandler.LOG_DAEMON,

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address = str("/dev/log")))

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syslogger.setFormatter(logging.Formatter

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('Mandos [%(process)d]: %(levelname)s:'

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' %(message)s'))

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logger.addHandler(syslogger)

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console = logging.StreamHandler()

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console.setFormatter(logging.Formatter('%(name)s [%(process)d]:'

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' %(levelname)s:'

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' %(message)s'))

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logger.addHandler(console)

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class AvahiError(Exception):

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def __init__(self, value, *args, **kwargs):

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self.value = value

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super(AvahiError, self).__init__(value, *args, **kwargs)

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def __unicode__(self):

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return unicode(repr(self.value))

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class AvahiServiceError(AvahiError):

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pass

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class AvahiGroupError(AvahiError):

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pass

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class AvahiService(object):

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"""An Avahi (Zeroconf) service.

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Attributes:

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interface: integer; avahi.IF_UNSPEC or an interface index.

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Used to optionally bind to the specified interface.

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name: string; Example: 'Mandos'

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type: string; Example: '_mandos._tcp'.

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See <http://www.dns-sd.org/ServiceTypes.html>

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port: integer; what port to announce

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TXT: list of strings; TXT record for the service

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domain: string; Domain to publish on, default to .local if empty.

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host: string; Host to publish records for, default is localhost

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max_renames: integer; maximum number of renames

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rename_count: integer; counter so we only rename after collisions

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a sensible number of times

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group: D-Bus Entry Group

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server: D-Bus Server

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bus: dbus.SystemBus()

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"""

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def __init__(self, interface = avahi.IF_UNSPEC, name = None,

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servicetype = None, port = None, TXT = None,

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domain = "", host = "", max_renames = 32768,

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protocol = avahi.PROTO_UNSPEC, bus = None):

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self.interface = interface

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self.name = name

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self.type = servicetype

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self.port = port

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self.TXT = TXT if TXT is not None else []

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self.domain = domain

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self.host = host

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self.rename_count = 0

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self.max_renames = max_renames

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self.protocol = protocol

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self.group = None # our entry group

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self.server = None

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self.bus = bus

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self.entry_group_state_changed_match = None

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def rename(self):

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"""Derived from the Avahi example code"""

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if self.rename_count >= self.max_renames:

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logger.critical("No suitable Zeroconf service name found"

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" after %i retries, exiting.",

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self.rename_count)

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raise AvahiServiceError("Too many renames")

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self.name = unicode(self.server.GetAlternativeServiceName(self.name))

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logger.info("Changing Zeroconf service name to %r ...",

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self.name)

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syslogger.setFormatter(logging.Formatter

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('Mandos (%s) [%%(process)d]:'

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' %%(levelname)s: %%(message)s'

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% self.name))

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self.remove()

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try:

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self.add()

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except dbus.exceptions.DBusException as error:

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logger.critical("DBusException: %s", error)

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self.cleanup()

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os._exit(1)

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self.rename_count += 1

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def remove(self):

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"""Derived from the Avahi example code"""

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if self.entry_group_state_changed_match is not None:

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self.entry_group_state_changed_match.remove()

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self.entry_group_state_changed_match = None

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if self.group is not None:

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self.group.Reset()

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def add(self):

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"""Derived from the Avahi example code"""

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self.remove()

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if self.group is None:

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self.group = dbus.Interface(

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self.bus.get_object(avahi.DBUS_NAME,

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self.server.EntryGroupNew()),

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avahi.DBUS_INTERFACE_ENTRY_GROUP)

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self.entry_group_state_changed_match = (

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self.group.connect_to_signal(

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'StateChanged', self .entry_group_state_changed))

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logger.debug("Adding Zeroconf service '%s' of type '%s' ...",

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self.name, self.type)

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self.group.AddService(

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self.interface,

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self.protocol,

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dbus.UInt32(0), # flags

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self.name, self.type,

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self.domain, self.host,

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dbus.UInt16(self.port),

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avahi.string_array_to_txt_array(self.TXT))

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self.group.Commit()

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def entry_group_state_changed(self, state, error):

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"""Derived from the Avahi example code"""

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logger.debug("Avahi entry group state change: %i", state)

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if state == avahi.ENTRY_GROUP_ESTABLISHED:

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logger.debug("Zeroconf service established.")

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elif state == avahi.ENTRY_GROUP_COLLISION:

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logger.info("Zeroconf service name collision.")

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self.rename()

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elif state == avahi.ENTRY_GROUP_FAILURE:

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logger.critical("Avahi: Error in group state changed %s",

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unicode(error))

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raise AvahiGroupError("State changed: %s"

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% unicode(error))

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def cleanup(self):

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"""Derived from the Avahi example code"""

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if self.group is not None:

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try:

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self.group.Free()

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except (dbus.exceptions.UnknownMethodException,

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dbus.exceptions.DBusException) as e:

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pass

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self.group = None

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self.remove()

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def server_state_changed(self, state, error=None):

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"""Derived from the Avahi example code"""

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logger.debug("Avahi server state change: %i", state)

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bad_states = { avahi.SERVER_INVALID:

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"Zeroconf server invalid",

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avahi.SERVER_REGISTERING: None,

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avahi.SERVER_COLLISION:

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"Zeroconf server name collision",

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avahi.SERVER_FAILURE:

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"Zeroconf server failure" }

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if state in bad_states:

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if bad_states[state] is not None:

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if error is None:

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logger.error(bad_states[state])

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else:

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logger.error(bad_states[state] + ": %r", error)

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self.cleanup()

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elif state == avahi.SERVER_RUNNING:

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self.add()

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else:

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if error is None:

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logger.debug("Unknown state: %r", state)

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else:

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logger.debug("Unknown state: %r: %r", state, error)

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def activate(self):

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"""Derived from the Avahi example code"""

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if self.server is None:

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self.server = dbus.Interface(

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self.bus.get_object(avahi.DBUS_NAME,

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avahi.DBUS_PATH_SERVER,

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follow_name_owner_changes=True),

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avahi.DBUS_INTERFACE_SERVER)

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self.server.connect_to_signal("StateChanged",

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self.server_state_changed)

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self.server_state_changed(self.server.GetState())

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class Client(object):

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"""A representation of a client host served by this server.

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Attributes:

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_approved: bool(); 'None' if not yet approved/disapproved

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approval_delay: datetime.timedelta(); Time to wait for approval

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approval_duration: datetime.timedelta(); Duration of one approval

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checker: subprocess.Popen(); a running checker process used

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to see if the client lives.

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'None' if no process is running.

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checker_callback_tag: a gobject event source tag, or None

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checker_command: string; External command which is run to check

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if client lives. %() expansions are done at

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runtime with vars(self) as dict, so that for

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instance %(name)s can be used in the command.

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checker_initiator_tag: a gobject event source tag, or None

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created: datetime.datetime(); (UTC) object creation

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current_checker_command: string; current running checker_command

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disable_hook: If set, called by disable() as disable_hook(self)

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disable_initiator_tag: a gobject event source tag, or None

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enabled: bool()

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fingerprint: string (40 or 32 hexadecimal digits); used to

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uniquely identify the client

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host: string; available for use by the checker command

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interval: datetime.timedelta(); How often to start a new checker

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last_approval_request: datetime.datetime(); (UTC) or None

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last_checked_ok: datetime.datetime(); (UTC) or None

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last_enabled: datetime.datetime(); (UTC)

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name: string; from the config file, used in log messages and

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D-Bus identifiers

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secret: bytestring; sent verbatim (over TLS) to client

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timeout: datetime.timedelta(); How long from last_checked_ok

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until this client is disabled

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runtime_expansions: Allowed attributes for runtime expansion.

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"""

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runtime_expansions = ("approval_delay", "approval_duration",

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"created", "enabled", "fingerprint",

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"host", "interval", "last_checked_ok",

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"last_enabled", "name", "timeout")

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@staticmethod

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def _timedelta_to_milliseconds(td):

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"Convert a datetime.timedelta() to milliseconds"

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return ((td.days * 24 * 60 * 60 * 1000)

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+ (td.seconds * 1000)

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+ (td.microseconds // 1000))

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def timeout_milliseconds(self):

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"Return the 'timeout' attribute in milliseconds"

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return self._timedelta_to_milliseconds(self.timeout)

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def interval_milliseconds(self):

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"Return the 'interval' attribute in milliseconds"

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return self._timedelta_to_milliseconds(self.interval)

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def approval_delay_milliseconds(self):

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return self._timedelta_to_milliseconds(self.approval_delay)

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def __init__(self, name = None, disable_hook=None, config=None):

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"""Note: the 'checker' key in 'config' sets the

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'checker_command' attribute and *not* the 'checker'

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attribute."""

330

self.name = name

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if config is None:

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config = {}

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logger.debug("Creating client %r", self.name)

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# Uppercase and remove spaces from fingerprint for later

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# comparison purposes with return value from the fingerprint()

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# function

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self.fingerprint = (config["fingerprint"].upper()

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.replace(" ", ""))

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logger.debug(" Fingerprint: %s", self.fingerprint)

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if "secret" in config:

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self.secret = config["secret"].decode("base64")

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elif "secfile" in config:

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with open(os.path.expanduser(os.path.expandvars

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(config["secfile"])),

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"rb") as secfile:

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self.secret = secfile.read()

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else:

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raise TypeError("No secret or secfile for client %s"

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% self.name)

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self.host = config.get("host", "")

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self.created = datetime.datetime.utcnow()

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self.enabled = False

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self.last_approval_request = None

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self.last_enabled = None

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self.last_checked_ok = None

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self.timeout = string_to_delta(config["timeout"])

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self.interval = string_to_delta(config["interval"])

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self.disable_hook = disable_hook

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self.checker = None

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self.checker_initiator_tag = None

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self.disable_initiator_tag = None

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self.checker_callback_tag = None

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self.checker_command = config["checker"]

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self.current_checker_command = None

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self.last_connect = None

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self._approved = None

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self.approved_by_default = config.get("approved_by_default",

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True)

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self.approvals_pending = 0

370

self.approval_delay = string_to_delta(

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config["approval_delay"])

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self.approval_duration = string_to_delta(

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config["approval_duration"])

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self.changedstate = multiprocessing_manager.Condition(multiprocessing_manager.Lock())

375

376

def send_changedstate(self):

377

self.changedstate.acquire()

378

self.changedstate.notify_all()

379

self.changedstate.release()

380

381

def enable(self):

382

"""Start this client's checker and timeout hooks"""

383

if getattr(self, "enabled", False):

384

# Already enabled

385

return

386

self.send_changedstate()

387

self.last_enabled = datetime.datetime.utcnow()

388

# Schedule a new checker to be started an 'interval' from now,

389

# and every interval from then on.

390

self.checker_initiator_tag = (gobject.timeout_add

391

(self.interval_milliseconds(),

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self.start_checker))

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# Schedule a disable() when 'timeout' has passed

394

self.disable_initiator_tag = (gobject.timeout_add

395

(self.timeout_milliseconds(),

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self.disable))

397

self.enabled = True

398

# Also start a new checker *right now*.

399

self.start_checker()

400

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def disable(self, quiet=True):

402

"""Disable this client."""

403

if not getattr(self, "enabled", False):

404

return False

405

if not quiet:

406

self.send_changedstate()

407

if not quiet:

408

logger.info("Disabling client %s", self.name)

409

if getattr(self, "disable_initiator_tag", False):

410

gobject.source_remove(self.disable_initiator_tag)

411

self.disable_initiator_tag = None

412

if getattr(self, "checker_initiator_tag", False):

413

gobject.source_remove(self.checker_initiator_tag)

414

self.checker_initiator_tag = None

415

self.stop_checker()

416

if self.disable_hook:

417

self.disable_hook(self)

418

self.enabled = False

419

# Do not run this again if called by a gobject.timeout_add

420

return False

421

422

def __del__(self):

423

self.disable_hook = None

424

self.disable()

425

426

def checker_callback(self, pid, condition, command):

427

"""The checker has completed, so take appropriate actions."""

428

self.checker_callback_tag = None

429

self.checker = None

430

if os.WIFEXITED(condition):

431

exitstatus = os.WEXITSTATUS(condition)

432

if exitstatus == 0:

433

logger.info("Checker for %(name)s succeeded",

434

vars(self))

435

self.checked_ok()

436

else:

437

logger.info("Checker for %(name)s failed",

438

vars(self))

439

else:

440

logger.warning("Checker for %(name)s crashed?",

441

vars(self))

442

443

def checked_ok(self):

444

"""Bump up the timeout for this client.

445

446

This should only be called when the client has been seen,

447

alive and well.

448

"""

449

self.last_checked_ok = datetime.datetime.utcnow()

450

gobject.source_remove(self.disable_initiator_tag)

451

self.disable_initiator_tag = (gobject.timeout_add

452

(self.timeout_milliseconds(),

453

self.disable))

454

455

def need_approval(self):

456

self.last_approval_request = datetime.datetime.utcnow()

457

458

def start_checker(self):

459

"""Start a new checker subprocess if one is not running.

460

461

If a checker already exists, leave it running and do

462

nothing."""

463

# The reason for not killing a running checker is that if we

464

# did that, then if a checker (for some reason) started

465

# running slowly and taking more than 'interval' time, the

466

# client would inevitably timeout, since no checker would get

467

# a chance to run to completion. If we instead leave running

468

# checkers alone, the checker would have to take more time

469

# than 'timeout' for the client to be disabled, which is as it

470

# should be.

471

472

# If a checker exists, make sure it is not a zombie

473

try:

474

pid, status = os.waitpid(self.checker.pid, os.WNOHANG)

475

except (AttributeError, OSError) as error:

476

if (isinstance(error, OSError)

477

and error.errno != errno.ECHILD):

478

raise error

479

else:

480

if pid:

481

logger.warning("Checker was a zombie")

482

gobject.source_remove(self.checker_callback_tag)

483

self.checker_callback(pid, status,

484

self.current_checker_command)

485

# Start a new checker if needed

486

if self.checker is None:

487

try:

488

# In case checker_command has exactly one % operator

489

command = self.checker_command % self.host

490

except TypeError:

491

# Escape attributes for the shell

492

escaped_attrs = dict(

493

(attr,

494

re.escape(unicode(str(getattr(self, attr, "")),

495

errors=

496

'replace')))

497

for attr in

498

self.runtime_expansions)

499

500

try:

501

command = self.checker_command % escaped_attrs

502

except TypeError as error:

503

logger.error('Could not format string "%s":'

504

' %s', self.checker_command, error)

505

return True # Try again later

506

self.current_checker_command = command

507

try:

508

logger.info("Starting checker %r for %s",

509

command, self.name)

510

# We don't need to redirect stdout and stderr, since

511

# in normal mode, that is already done by daemon(),

512

# and in debug mode we don't want to. (Stdin is

513

# always replaced by /dev/null.)

514

self.checker = subprocess.Popen(command,

515

close_fds=True,

516

shell=True, cwd="/")

517

self.checker_callback_tag = (gobject.child_watch_add

518

(self.checker.pid,

519

self.checker_callback,

520

data=command))

521

# The checker may have completed before the gobject

522

# watch was added. Check for this.

523

pid, status = os.waitpid(self.checker.pid, os.WNOHANG)

524

if pid:

525

gobject.source_remove(self.checker_callback_tag)

526

self.checker_callback(pid, status, command)

527

except OSError as error:

528

logger.error("Failed to start subprocess: %s",

529

error)

530

# Re-run this periodically if run by gobject.timeout_add

531

return True

532

533

def stop_checker(self):

534

"""Force the checker process, if any, to stop."""

535

if self.checker_callback_tag:

536

gobject.source_remove(self.checker_callback_tag)

537

self.checker_callback_tag = None

538

if getattr(self, "checker", None) is None:

539

return

540

logger.debug("Stopping checker for %(name)s", vars(self))

541

try:

542

os.kill(self.checker.pid, signal.SIGTERM)

543

#time.sleep(0.5)

544

#if self.checker.poll() is None:

545

# os.kill(self.checker.pid, signal.SIGKILL)

546

except OSError as error:

547

if error.errno != errno.ESRCH: # No such process

548

raise

549

self.checker = None

550

551

def dbus_service_property(dbus_interface, signature="v",

552

access="readwrite", byte_arrays=False):

553

"""Decorators for marking methods of a DBusObjectWithProperties to

554

become properties on the D-Bus.

555

556

The decorated method will be called with no arguments by "Get"

557

and with one argument by "Set".

558

559

The parameters, where they are supported, are the same as

560

dbus.service.method, except there is only "signature", since the

561

type from Get() and the type sent to Set() is the same.

562

"""

563

# Encoding deeply encoded byte arrays is not supported yet by the

564

# "Set" method, so we fail early here:

565

if byte_arrays and signature != "ay":

566

raise ValueError("Byte arrays not supported for non-'ay'"

567

" signature %r" % signature)

568

def decorator(func):

569

func._dbus_is_property = True

570

func._dbus_interface = dbus_interface

571

func._dbus_signature = signature

572

func._dbus_access = access

573

func._dbus_name = func.__name__

574

if func._dbus_name.endswith("_dbus_property"):

575

func._dbus_name = func._dbus_name[:-14]

576

func._dbus_get_args_options = {'byte_arrays': byte_arrays }

577

return func

578

return decorator

579

580

581

class DBusPropertyException(dbus.exceptions.DBusException):

582

"""A base class for D-Bus property-related exceptions

583

"""

584

def __unicode__(self):

585

return unicode(str(self))

586

587

588

class DBusPropertyAccessException(DBusPropertyException):

589

"""A property's access permissions disallows an operation.

590

"""

591

pass

592

593

594

class DBusPropertyNotFound(DBusPropertyException):

595

"""An attempt was made to access a non-existing property.

596

"""

597

pass

598

599

600

class DBusObjectWithProperties(dbus.service.Object):

601

"""A D-Bus object with properties.

602

603

Classes inheriting from this can use the dbus_service_property

604

decorator to expose methods as D-Bus properties. It exposes the

605

standard Get(), Set(), and GetAll() methods on the D-Bus.

606

"""

607

608

@staticmethod

609

def _is_dbus_property(obj):

610

return getattr(obj, "_dbus_is_property", False)

611

612

def _get_all_dbus_properties(self):

613

"""Returns a generator of (name, attribute) pairs

614

"""

615

return ((prop._dbus_name, prop)

616

for name, prop in

617

inspect.getmembers(self, self._is_dbus_property))

618

619

def _get_dbus_property(self, interface_name, property_name):

620

"""Returns a bound method if one exists which is a D-Bus

621

property with the specified name and interface.

622

"""

623

for name in (property_name,

624

property_name + "_dbus_property"):

625

prop = getattr(self, name, None)

626

if (prop is None

627

or not self._is_dbus_property(prop)

628

or prop._dbus_name != property_name

629

or (interface_name and prop._dbus_interface

630

and interface_name != prop._dbus_interface)):

631

continue

632

return prop

633

# No such property

634

raise DBusPropertyNotFound(self.dbus_object_path + ":"

635

+ interface_name + "."

636

+ property_name)

637

638

@dbus.service.method(dbus.PROPERTIES_IFACE, in_signature="ss",

639

out_signature="v")

640

def Get(self, interface_name, property_name):

641

"""Standard D-Bus property Get() method, see D-Bus standard.

642

"""

643

prop = self._get_dbus_property(interface_name, property_name)

644

if prop._dbus_access == "write":

645

raise DBusPropertyAccessException(property_name)

646

value = prop()

647

if not hasattr(value, "variant_level"):

648

return value

649

return type(value)(value, variant_level=value.variant_level+1)

650

651

@dbus.service.method(dbus.PROPERTIES_IFACE, in_signature="ssv")

652

def Set(self, interface_name, property_name, value):

653

"""Standard D-Bus property Set() method, see D-Bus standard.

654

"""

655

prop = self._get_dbus_property(interface_name, property_name)

656

if prop._dbus_access == "read":

657

raise DBusPropertyAccessException(property_name)

658

if prop._dbus_get_args_options["byte_arrays"]:

659

# The byte_arrays option is not supported yet on

660

# signatures other than "ay".

661

if prop._dbus_signature != "ay":

662

raise ValueError

663

value = dbus.ByteArray(''.join(unichr(byte)

664

for byte in value))

665

prop(value)

666

667

@dbus.service.method(dbus.PROPERTIES_IFACE, in_signature="s",

668

out_signature="a{sv}")

669

def GetAll(self, interface_name):

670

"""Standard D-Bus property GetAll() method, see D-Bus

671

standard.

672

673

Note: Will not include properties with access="write".

674

"""

675

all = {}

676

for name, prop in self._get_all_dbus_properties():

677

if (interface_name

678

and interface_name != prop._dbus_interface):

679

# Interface non-empty but did not match

680

continue

681

# Ignore write-only properties

682

if prop._dbus_access == "write":

683

continue

684

value = prop()

685

if not hasattr(value, "variant_level"):

686

all[name] = value

687

continue

688

all[name] = type(value)(value, variant_level=

689

value.variant_level+1)

690

return dbus.Dictionary(all, signature="sv")

691

692

@dbus.service.method(dbus.INTROSPECTABLE_IFACE,

693

out_signature="s",

694

path_keyword='object_path',

695

connection_keyword='connection')

696

def Introspect(self, object_path, connection):

697

"""Standard D-Bus method, overloaded to insert property tags.

698

"""

699

xmlstring = dbus.service.Object.Introspect(self, object_path,

700

connection)

701

try:

702

document = xml.dom.minidom.parseString(xmlstring)

703

def make_tag(document, name, prop):

704

e = document.createElement("property")

705

e.setAttribute("name", name)

706

e.setAttribute("type", prop._dbus_signature)

707

e.setAttribute("access", prop._dbus_access)

708

return e

709

for if_tag in document.getElementsByTagName("interface"):

710

for tag in (make_tag(document, name, prop)

711

for name, prop

712

in self._get_all_dbus_properties()

713

if prop._dbus_interface

714

== if_tag.getAttribute("name")):

715

if_tag.appendChild(tag)

716

# Add the names to the return values for the

717

# "org.freedesktop.DBus.Properties" methods

718

if (if_tag.getAttribute("name")

719

== "org.freedesktop.DBus.Properties"):

720

for cn in if_tag.getElementsByTagName("method"):

721

if cn.getAttribute("name") == "Get":

722

for arg in cn.getElementsByTagName("arg"):

723

if (arg.getAttribute("direction")

724

== "out"):

725

arg.setAttribute("name", "value")

726

elif cn.getAttribute("name") == "GetAll":

727

for arg in cn.getElementsByTagName("arg"):

728

if (arg.getAttribute("direction")

729

== "out"):

730

arg.setAttribute("name", "props")

731

xmlstring = document.toxml("utf-8")

732

document.unlink()

733

except (AttributeError, xml.dom.DOMException,

734

xml.parsers.expat.ExpatError) as error:

735

logger.error("Failed to override Introspection method",

736

error)

737

return xmlstring

738

739

740

class ClientDBus(Client, DBusObjectWithProperties):

741

"""A Client class using D-Bus

742

743

Attributes:

744

dbus_object_path: dbus.ObjectPath

745

bus: dbus.SystemBus()

746

"""

747

748

runtime_expansions = (Client.runtime_expansions

749

+ ("dbus_object_path",))

750

751

# dbus.service.Object doesn't use super(), so we can't either.

752

753

def __init__(self, bus = None, *args, **kwargs):

754

self._approvals_pending = 0

755

self.bus = bus

756

Client.__init__(self, *args, **kwargs)

757

# Only now, when this client is initialized, can it show up on

758

# the D-Bus

759

client_object_name = unicode(self.name).translate(

760

{ord("."): ord("_"),

761

ord("-"): ord("_")})

762

self.dbus_object_path = (dbus.ObjectPath

763

("/clients/" + client_object_name))

764

DBusObjectWithProperties.__init__(self, self.bus,

765

self.dbus_object_path)

766

767

def _get_approvals_pending(self):

768

return self._approvals_pending

769

def _set_approvals_pending(self, value):

770

old_value = self._approvals_pending

771

self._approvals_pending = value

772

bval = bool(value)

773

if (hasattr(self, "dbus_object_path")

774

and bval is not bool(old_value)):

775

dbus_bool = dbus.Boolean(bval, variant_level=1)

776

self.PropertyChanged(dbus.String("ApprovalPending"),

777

dbus_bool)

778

779

approvals_pending = property(_get_approvals_pending,

780

_set_approvals_pending)

781

del _get_approvals_pending, _set_approvals_pending

782

783

@staticmethod

784

def _datetime_to_dbus(dt, variant_level=0):

785

"""Convert a UTC datetime.datetime() to a D-Bus type."""

786

return dbus.String(dt.isoformat(),

787

variant_level=variant_level)

788

789

def enable(self):

790

oldstate = getattr(self, "enabled", False)

791

r = Client.enable(self)

792

if oldstate != self.enabled:

793

# Emit D-Bus signals

794

self.PropertyChanged(dbus.String("Enabled"),

795

dbus.Boolean(True, variant_level=1))

796

self.PropertyChanged(

797

dbus.String("LastEnabled"),

798

self._datetime_to_dbus(self.last_enabled,

799

variant_level=1))

800

return r

801

802

def disable(self, quiet = False):

803

oldstate = getattr(self, "enabled", False)

804

r = Client.disable(self, quiet=quiet)

805

if not quiet and oldstate != self.enabled:

806

# Emit D-Bus signal

807

self.PropertyChanged(dbus.String("Enabled"),

808

dbus.Boolean(False, variant_level=1))

809

return r

810

811

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

812

try:

813

self.remove_from_connection()

814

except LookupError:

815

pass

816

if hasattr(DBusObjectWithProperties, "__del__"):

817

DBusObjectWithProperties.__del__(self, *args, **kwargs)

818

Client.__del__(self, *args, **kwargs)

819

820

def checker_callback(self, pid, condition, command,

821

*args, **kwargs):

822

self.checker_callback_tag = None

823

self.checker = None

824

# Emit D-Bus signal

825

self.PropertyChanged(dbus.String("CheckerRunning"),

826

dbus.Boolean(False, variant_level=1))

827

if os.WIFEXITED(condition):

828

exitstatus = os.WEXITSTATUS(condition)

829

# Emit D-Bus signal

830

self.CheckerCompleted(dbus.Int16(exitstatus),

831

dbus.Int64(condition),

832

dbus.String(command))

833

else:

834

# Emit D-Bus signal

835

self.CheckerCompleted(dbus.Int16(-1),

836

dbus.Int64(condition),

837

dbus.String(command))

838

839

return Client.checker_callback(self, pid, condition, command,

840

*args, **kwargs)

841

842

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

843

Client.checked_ok(self, *args, **kwargs)

844

# Emit D-Bus signal

845

self.PropertyChanged(

846

dbus.String("LastCheckedOK"),

847

(self._datetime_to_dbus(self.last_checked_ok,

848

variant_level=1)))

849

850

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

851

r = Client.need_approval(self, *args, **kwargs)

852

# Emit D-Bus signal

853

self.PropertyChanged(

854

dbus.String("LastApprovalRequest"),

855

(self._datetime_to_dbus(self.last_approval_request,

856

variant_level=1)))

857

return r

858

859

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

860

old_checker = self.checker

861

if self.checker is not None:

862

old_checker_pid = self.checker.pid

863

else:

864

old_checker_pid = None

865

r = Client.start_checker(self, *args, **kwargs)

866

# Only if new checker process was started

867

if (self.checker is not None

868

and old_checker_pid != self.checker.pid):

869

# Emit D-Bus signal

870

self.CheckerStarted(self.current_checker_command)

871

self.PropertyChanged(

872

dbus.String("CheckerRunning"),

873

dbus.Boolean(True, variant_level=1))

874

return r

875

876

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

877

old_checker = getattr(self, "checker", None)

878

r = Client.stop_checker(self, *args, **kwargs)

879

if (old_checker is not None

880

and getattr(self, "checker", None) is None):

881

self.PropertyChanged(dbus.String("CheckerRunning"),

882

dbus.Boolean(False, variant_level=1))

883

return r

884

885

def _reset_approved(self):

886

self._approved = None

887

return False

888

889

def approve(self, value=True):

890

self.send_changedstate()

891

self._approved = value

892

gobject.timeout_add(self._timedelta_to_milliseconds

893

(self.approval_duration),

894

self._reset_approved)

895

896

897

## D-Bus methods, signals & properties

898

_interface = "se.bsnet.fukt.Mandos.Client"

899

900

## Signals

901

902

# CheckerCompleted - signal

903

@dbus.service.signal(_interface, signature="nxs")

904

def CheckerCompleted(self, exitcode, waitstatus, command):

905

"D-Bus signal"

906

pass

907

908

# CheckerStarted - signal

909

@dbus.service.signal(_interface, signature="s")

910

def CheckerStarted(self, command):

911

"D-Bus signal"

912

pass

913

914

# PropertyChanged - signal

915

@dbus.service.signal(_interface, signature="sv")

916

def PropertyChanged(self, property, value):

917

"D-Bus signal"

918

pass

919

920

# GotSecret - signal

921

@dbus.service.signal(_interface)

922

def GotSecret(self):

923

"""D-Bus signal

924

Is sent after a successful transfer of secret from the Mandos

925

server to mandos-client

926

"""

927

pass

928

929

# Rejected - signal

930

@dbus.service.signal(_interface, signature="s")

931

def Rejected(self, reason):

932

"D-Bus signal"

933

pass

934

935

# NeedApproval - signal

936

@dbus.service.signal(_interface, signature="tb")

937

def NeedApproval(self, timeout, default):

938

"D-Bus signal"

939

return self.need_approval()

940

941

## Methods

942

943

# Approve - method

944

@dbus.service.method(_interface, in_signature="b")

945

def Approve(self, value):

946

self.approve(value)

947

948

# CheckedOK - method

949

@dbus.service.method(_interface)

950

def CheckedOK(self):

951

self.checked_ok()

952

953

# Enable - method

954

@dbus.service.method(_interface)

955

def Enable(self):

956

"D-Bus method"

957

self.enable()

958

959

# StartChecker - method

960

@dbus.service.method(_interface)

961

def StartChecker(self):

962

"D-Bus method"

963

self.start_checker()

964

965

# Disable - method

966

@dbus.service.method(_interface)

967

def Disable(self):

968

"D-Bus method"

969

self.disable()

970

971

# StopChecker - method

972

@dbus.service.method(_interface)

973

def StopChecker(self):

974

self.stop_checker()

975

976

## Properties

977

978

# ApprovalPending - property

979

@dbus_service_property(_interface, signature="b", access="read")

980

def ApprovalPending_dbus_property(self):

981

return dbus.Boolean(bool(self.approvals_pending))

982

983

# ApprovedByDefault - property

984

@dbus_service_property(_interface, signature="b",

985

access="readwrite")

986

def ApprovedByDefault_dbus_property(self, value=None):

987

if value is None: # get

988

return dbus.Boolean(self.approved_by_default)

989

self.approved_by_default = bool(value)

990

# Emit D-Bus signal

991

self.PropertyChanged(dbus.String("ApprovedByDefault"),

992

dbus.Boolean(value, variant_level=1))

993

994

# ApprovalDelay - property

995

@dbus_service_property(_interface, signature="t",

996

access="readwrite")

997

def ApprovalDelay_dbus_property(self, value=None):

998

if value is None: # get

999

return dbus.UInt64(self.approval_delay_milliseconds())

1000

self.approval_delay = datetime.timedelta(0, 0, 0, value)

1001

# Emit D-Bus signal

1002

self.PropertyChanged(dbus.String("ApprovalDelay"),

1003

dbus.UInt64(value, variant_level=1))

1004

1005

# ApprovalDuration - property

1006

@dbus_service_property(_interface, signature="t",

1007

access="readwrite")

1008

def ApprovalDuration_dbus_property(self, value=None):

1009

if value is None: # get

1010

return dbus.UInt64(self._timedelta_to_milliseconds(

1011

self.approval_duration))

1012

self.approval_duration = datetime.timedelta(0, 0, 0, value)

1013

# Emit D-Bus signal

1014

self.PropertyChanged(dbus.String("ApprovalDuration"),

1015

dbus.UInt64(value, variant_level=1))

1016

1017

# Name - property

1018

@dbus_service_property(_interface, signature="s", access="read")

1019

def Name_dbus_property(self):

1020

return dbus.String(self.name)

1021

1022

# Fingerprint - property

1023

@dbus_service_property(_interface, signature="s", access="read")

1024

def Fingerprint_dbus_property(self):

1025

return dbus.String(self.fingerprint)

1026

1027

# Host - property

1028

@dbus_service_property(_interface, signature="s",

1029

access="readwrite")

1030

def Host_dbus_property(self, value=None):

1031

if value is None: # get

1032

return dbus.String(self.host)

1033

self.host = value

1034

# Emit D-Bus signal

1035

self.PropertyChanged(dbus.String("Host"),

1036

dbus.String(value, variant_level=1))

1037

1038

# Created - property

1039

@dbus_service_property(_interface, signature="s", access="read")

1040

def Created_dbus_property(self):

1041

return dbus.String(self._datetime_to_dbus(self.created))

1042

1043

# LastEnabled - property

1044

@dbus_service_property(_interface, signature="s", access="read")

1045

def LastEnabled_dbus_property(self):

1046

if self.last_enabled is None:

1047

return dbus.String("")

1048

return dbus.String(self._datetime_to_dbus(self.last_enabled))

1049

1050

# Enabled - property

1051

@dbus_service_property(_interface, signature="b",

1052

access="readwrite")

1053

def Enabled_dbus_property(self, value=None):

1054

if value is None: # get

1055

return dbus.Boolean(self.enabled)

1056

if value:

1057

self.enable()

1058

else:

1059

self.disable()

1060

1061

# LastCheckedOK - property

1062

@dbus_service_property(_interface, signature="s",

1063

access="readwrite")

1064

def LastCheckedOK_dbus_property(self, value=None):

1065

if value is not None:

1066

self.checked_ok()

1067

return

1068

if self.last_checked_ok is None:

1069

return dbus.String("")

1070

return dbus.String(self._datetime_to_dbus(self

1071

.last_checked_ok))

1072

1073

# LastApprovalRequest - property

1074

@dbus_service_property(_interface, signature="s", access="read")

1075

def LastApprovalRequest_dbus_property(self):

1076

if self.last_approval_request is None:

1077

return dbus.String("")

1078

return dbus.String(self.

1079

_datetime_to_dbus(self

1080

.last_approval_request))

1081

1082

# Timeout - property

1083

@dbus_service_property(_interface, signature="t",

1084

access="readwrite")

1085

def Timeout_dbus_property(self, value=None):

1086

if value is None: # get

1087

return dbus.UInt64(self.timeout_milliseconds())

1088

self.timeout = datetime.timedelta(0, 0, 0, value)

1089

# Emit D-Bus signal

1090

self.PropertyChanged(dbus.String("Timeout"),

1091

dbus.UInt64(value, variant_level=1))

1092

if getattr(self, "disable_initiator_tag", None) is None:

1093

return

1094

# Reschedule timeout

1095

gobject.source_remove(self.disable_initiator_tag)

1096

self.disable_initiator_tag = None

1097

time_to_die = (self.

1098

_timedelta_to_milliseconds((self

1099

.last_checked_ok

1100

+ self.timeout)

1101

- datetime.datetime

1102

.utcnow()))

1103

if time_to_die <= 0:

1104

# The timeout has passed

1105

self.disable()

1106

else:

1107

self.disable_initiator_tag = (gobject.timeout_add

1108

(time_to_die, self.disable))

1109

1110

# Interval - property

1111

@dbus_service_property(_interface, signature="t",

1112

access="readwrite")

1113

def Interval_dbus_property(self, value=None):

1114

if value is None: # get

1115

return dbus.UInt64(self.interval_milliseconds())

1116

self.interval = datetime.timedelta(0, 0, 0, value)

1117

# Emit D-Bus signal

1118

self.PropertyChanged(dbus.String("Interval"),

1119

dbus.UInt64(value, variant_level=1))

1120

if getattr(self, "checker_initiator_tag", None) is None:

1121

return

1122

# Reschedule checker run

1123

gobject.source_remove(self.checker_initiator_tag)

1124

self.checker_initiator_tag = (gobject.timeout_add

1125

(value, self.start_checker))

1126

self.start_checker() # Start one now, too

1127

1128

# Checker - property

1129

@dbus_service_property(_interface, signature="s",

1130

access="readwrite")

1131

def Checker_dbus_property(self, value=None):

1132

if value is None: # get

1133

return dbus.String(self.checker_command)

1134

self.checker_command = value

1135

# Emit D-Bus signal

1136

self.PropertyChanged(dbus.String("Checker"),

1137

dbus.String(self.checker_command,

1138

variant_level=1))

1139

1140

# CheckerRunning - property

1141

@dbus_service_property(_interface, signature="b",

1142

access="readwrite")

1143

def CheckerRunning_dbus_property(self, value=None):

1144

if value is None: # get

1145

return dbus.Boolean(self.checker is not None)

1146

if value:

1147

self.start_checker()

1148

else:

1149

self.stop_checker()

1150

1151

# ObjectPath - property

1152

@dbus_service_property(_interface, signature="o", access="read")

1153

def ObjectPath_dbus_property(self):

1154

return self.dbus_object_path # is already a dbus.ObjectPath

1155

1156

# Secret = property

1157

@dbus_service_property(_interface, signature="ay",

1158

access="write", byte_arrays=True)

1159

def Secret_dbus_property(self, value):

1160

self.secret = str(value)

1161

1162

del _interface

1163

1164

1165

class ProxyClient(object):

1166

def __init__(self, child_pipe, fpr, address):

1167

self._pipe = child_pipe

1168

self._pipe.send(('init', fpr, address))

1169

if not self._pipe.recv():

1170

raise KeyError()

1171

1172

def __getattribute__(self, name):

1173

if(name == '_pipe'):

1174

return super(ProxyClient, self).__getattribute__(name)

1175

self._pipe.send(('getattr', name))

1176

data = self._pipe.recv()

1177

if data[0] == 'data':

1178

return data[1]

1179

if data[0] == 'function':

1180

def func(*args, **kwargs):

1181

self._pipe.send(('funcall', name, args, kwargs))

1182

return self._pipe.recv()[1]

1183

return func

1184

1185

def __setattr__(self, name, value):

1186

if(name == '_pipe'):

1187

return super(ProxyClient, self).__setattr__(name, value)

1188

self._pipe.send(('setattr', name, value))

1189

1190

1191

class ClientHandler(socketserver.BaseRequestHandler, object):

1192

"""A class to handle client connections.

1193

1194

Instantiated once for each connection to handle it.

1195

Note: This will run in its own forked process."""

1196

1197

def handle(self):

1198

with contextlib.closing(self.server.child_pipe) as child_pipe:

1199

logger.info("TCP connection from: %s",

1200

unicode(self.client_address))

1201

logger.debug("Pipe FD: %d",

1202

self.server.child_pipe.fileno())

1203

1204

session = (gnutls.connection

1205

.ClientSession(self.request,

1206

gnutls.connection

1207

.X509Credentials()))

1208

1209

# Note: gnutls.connection.X509Credentials is really a

1210

# generic GnuTLS certificate credentials object so long as

1211

# no X.509 keys are added to it. Therefore, we can use it

1212

# here despite using OpenPGP certificates.

1213

1214

#priority = ':'.join(("NONE", "+VERS-TLS1.1",

1215

# "+AES-256-CBC", "+SHA1",

1216

# "+COMP-NULL", "+CTYPE-OPENPGP",

1217

# "+DHE-DSS"))

1218

# Use a fallback default, since this MUST be set.

1219

priority = self.server.gnutls_priority

1220

if priority is None:

1221

priority = "NORMAL"

1222

(gnutls.library.functions

1223

.gnutls_priority_set_direct(session._c_object,

1224

priority, None))

1225

1226

# Start communication using the Mandos protocol

1227

# Get protocol number

1228

line = self.request.makefile().readline()

1229

logger.debug("Protocol version: %r", line)

1230

try:

1231

if int(line.strip().split()[0]) > 1:

1232

raise RuntimeError

1233

except (ValueError, IndexError, RuntimeError) as error:

1234

logger.error("Unknown protocol version: %s", error)

1235

return

1236

1237

# Start GnuTLS connection

1238

try:

1239

session.handshake()

1240

except gnutls.errors.GNUTLSError as error:

1241

logger.warning("Handshake failed: %s", error)

1242

# Do not run session.bye() here: the session is not

1243

# established. Just abandon the request.

1244

return

1245

logger.debug("Handshake succeeded")

1246

1247

approval_required = False

1248

try:

1249

try:

1250

fpr = self.fingerprint(self.peer_certificate

1251

(session))

1252

except (TypeError,

1253

gnutls.errors.GNUTLSError) as error:

1254

logger.warning("Bad certificate: %s", error)

1255

return

1256

logger.debug("Fingerprint: %s", fpr)

1257

1258

try:

1259

client = ProxyClient(child_pipe, fpr,

1260

self.client_address)

1261

except KeyError:

1262

return

1263

1264

if client.approval_delay:

1265

delay = client.approval_delay

1266

client.approvals_pending += 1

1267

approval_required = True

1268

1269

while True:

1270

if not client.enabled:

1271

logger.info("Client %s is disabled",

1272

client.name)

1273

if self.server.use_dbus:

1274

# Emit D-Bus signal

1275

client.Rejected("Disabled")

1276

return

1277

1278

if client._approved or not client.approval_delay:

1279

#We are approved or approval is disabled

1280

break

1281

elif client._approved is None:

1282

logger.info("Client %s needs approval",

1283

client.name)

1284

if self.server.use_dbus:

1285

# Emit D-Bus signal

1286

client.NeedApproval(

1287

client.approval_delay_milliseconds(),

1288

client.approved_by_default)

1289

else:

1290

logger.warning("Client %s was not approved",

1291

client.name)

1292

if self.server.use_dbus:

1293

# Emit D-Bus signal

1294

client.Rejected("Denied")

1295

return

1296

1297

#wait until timeout or approved

1298

#x = float(client._timedelta_to_milliseconds(delay))

1299

time = datetime.datetime.now()

1300

client.changedstate.acquire()

1301

client.changedstate.wait(float(client._timedelta_to_milliseconds(delay) / 1000))

1302

client.changedstate.release()

1303

time2 = datetime.datetime.now()

1304

if (time2 - time) >= delay:

1305

if not client.approved_by_default:

1306

logger.warning("Client %s timed out while"

1307

" waiting for approval",

1308

client.name)

1309

if self.server.use_dbus:

1310

# Emit D-Bus signal

1311

client.Rejected("Approval timed out")

1312

return

1313

else:

1314

break

1315

else:

1316

delay -= time2 - time

1317

1318

sent_size = 0

1319

while sent_size < len(client.secret):

1320

try:

1321

sent = session.send(client.secret[sent_size:])

1322

except gnutls.errors.GNUTLSError as error:

1323

logger.warning("gnutls send failed")

1324

return

1325

logger.debug("Sent: %d, remaining: %d",

1326

sent, len(client.secret)

1327

- (sent_size + sent))

1328

sent_size += sent

1329

1330

logger.info("Sending secret to %s", client.name)

1331

# bump the timeout as if seen

1332

client.checked_ok()

1333

if self.server.use_dbus:

1334

# Emit D-Bus signal

1335

client.GotSecret()

1336

1337

finally:

1338

if approval_required:

1339

client.approvals_pending -= 1

1340

try:

1341

session.bye()

1342

except gnutls.errors.GNUTLSError as error:

1343

logger.warning("GnuTLS bye failed")

1344

1345

@staticmethod

1346

def peer_certificate(session):

1347

"Return the peer's OpenPGP certificate as a bytestring"

1348

# If not an OpenPGP certificate...

1349

if (gnutls.library.functions

1350

.gnutls_certificate_type_get(session._c_object)

1351

!= gnutls.library.constants.GNUTLS_CRT_OPENPGP):

1352

# ...do the normal thing

1353

return session.peer_certificate

1354

list_size = ctypes.c_uint(1)

1355

cert_list = (gnutls.library.functions

1356

.gnutls_certificate_get_peers

1357

(session._c_object, ctypes.byref(list_size)))

1358

if not bool(cert_list) and list_size.value != 0:

1359

raise gnutls.errors.GNUTLSError("error getting peer"

1360

" certificate")

1361

if list_size.value == 0:

1362

return None

1363

cert = cert_list[0]

1364

return ctypes.string_at(cert.data, cert.size)

1365

1366

@staticmethod

1367

def fingerprint(openpgp):

1368

"Convert an OpenPGP bytestring to a hexdigit fingerprint"

1369

# New GnuTLS "datum" with the OpenPGP public key

1370

datum = (gnutls.library.types

1371

.gnutls_datum_t(ctypes.cast(ctypes.c_char_p(openpgp),

1372

ctypes.POINTER

1373

(ctypes.c_ubyte)),

1374

ctypes.c_uint(len(openpgp))))

1375

# New empty GnuTLS certificate

1376

crt = gnutls.library.types.gnutls_openpgp_crt_t()

1377

(gnutls.library.functions

1378

.gnutls_openpgp_crt_init(ctypes.byref(crt)))

1379

# Import the OpenPGP public key into the certificate

1380

(gnutls.library.functions

1381

.gnutls_openpgp_crt_import(crt, ctypes.byref(datum),

1382

gnutls.library.constants

1383

.GNUTLS_OPENPGP_FMT_RAW))

1384

# Verify the self signature in the key

1385

crtverify = ctypes.c_uint()

1386

(gnutls.library.functions

1387

.gnutls_openpgp_crt_verify_self(crt, 0,

1388

ctypes.byref(crtverify)))

1389

if crtverify.value != 0:

1390

gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)

1391

raise (gnutls.errors.CertificateSecurityError

1392

("Verify failed"))

1393

# New buffer for the fingerprint

1394

buf = ctypes.create_string_buffer(20)

1395

buf_len = ctypes.c_size_t()

1396

# Get the fingerprint from the certificate into the buffer

1397

(gnutls.library.functions

1398

.gnutls_openpgp_crt_get_fingerprint(crt, ctypes.byref(buf),

1399

ctypes.byref(buf_len)))

1400

# Deinit the certificate

1401

gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)

1402

# Convert the buffer to a Python bytestring

1403

fpr = ctypes.string_at(buf, buf_len.value)

1404

# Convert the bytestring to hexadecimal notation

1405

hex_fpr = ''.join("%02X" % ord(char) for char in fpr)

1406

return hex_fpr

1407

1408

1409

class MultiprocessingMixIn(object):

1410

"""Like socketserver.ThreadingMixIn, but with multiprocessing"""

1411

def sub_process_main(self, request, address):

1412

try:

1413

self.finish_request(request, address)

1414

except:

1415

self.handle_error(request, address)

1416

self.close_request(request)

1417

1418

def process_request(self, request, address):

1419

"""Start a new process to process the request."""

1420

multiprocessing.Process(target = self.sub_process_main,

1421

args = (request, address)).start()

1422

1423

class MultiprocessingMixInWithPipe(MultiprocessingMixIn, object):

1424

""" adds a pipe to the MixIn """

1425

def process_request(self, request, client_address):

1426

"""Overrides and wraps the original process_request().

1427

1428

This function creates a new pipe in self.pipe

1429

"""

1430

parent_pipe, self.child_pipe = multiprocessing.Pipe()

1431

1432

super(MultiprocessingMixInWithPipe,

1433

self).process_request(request, client_address)

1434

self.child_pipe.close()

1435

self.add_pipe(parent_pipe)

1436

1437

def add_pipe(self, parent_pipe):

1438

"""Dummy function; override as necessary"""

1439

raise NotImplementedError

1440

1441

class IPv6_TCPServer(MultiprocessingMixInWithPipe,

1442

socketserver.TCPServer, object):

1443

"""IPv6-capable TCP server. Accepts 'None' as address and/or port

1444

1445

Attributes:

1446

enabled: Boolean; whether this server is activated yet

1447

interface: None or a network interface name (string)

1448

use_ipv6: Boolean; to use IPv6 or not

1449

"""

1450

def __init__(self, server_address, RequestHandlerClass,

1451

interface=None, use_ipv6=True):

1452

self.interface = interface

1453

if use_ipv6:

1454

self.address_family = socket.AF_INET6

1455

socketserver.TCPServer.__init__(self, server_address,

1456

RequestHandlerClass)

1457

def server_bind(self):

1458

"""This overrides the normal server_bind() function

1459

to bind to an interface if one was specified, and also NOT to

1460

bind to an address or port if they were not specified."""

1461

if self.interface is not None:

1462

if SO_BINDTODEVICE is None:

1463

logger.error("SO_BINDTODEVICE does not exist;"

1464

" cannot bind to interface %s",

1465

self.interface)

1466

else:

1467

try:

1468

self.socket.setsockopt(socket.SOL_SOCKET,

1469

SO_BINDTODEVICE,

1470

str(self.interface

1471

+ '\0'))

1472

except socket.error as error:

1473

if error[0] == errno.EPERM:

1474

logger.error("No permission to"

1475

" bind to interface %s",

1476

self.interface)

1477

elif error[0] == errno.ENOPROTOOPT:

1478

logger.error("SO_BINDTODEVICE not available;"

1479

" cannot bind to interface %s",

1480

self.interface)

1481

else:

1482

raise

1483

# Only bind(2) the socket if we really need to.

1484

if self.server_address[0] or self.server_address[1]:

1485

if not self.server_address[0]:

1486

if self.address_family == socket.AF_INET6:

1487

any_address = "::" # in6addr_any

1488

else:

1489

any_address = socket.INADDR_ANY

1490

self.server_address = (any_address,

1491

self.server_address[1])

1492

elif not self.server_address[1]:

1493

self.server_address = (self.server_address[0],

1494

0)

1495

# if self.interface:

1496

# self.server_address = (self.server_address[0],

1497

# 0, # port

1498

# 0, # flowinfo

1499

# if_nametoindex

1500

# (self.interface))

1501

return socketserver.TCPServer.server_bind(self)

1502

1503

1504

class MandosServer(IPv6_TCPServer):

1505

"""Mandos server.

1506

1507

Attributes:

1508

clients: set of Client objects

1509

gnutls_priority GnuTLS priority string

1510

use_dbus: Boolean; to emit D-Bus signals or not

1511

1512

Assumes a gobject.MainLoop event loop.

1513

"""

1514

def __init__(self, server_address, RequestHandlerClass,

1515

interface=None, use_ipv6=True, clients=None,

1516

gnutls_priority=None, use_dbus=True):

1517

self.enabled = False

1518

self.clients = clients

1519

if self.clients is None:

1520

self.clients = set()

1521

self.use_dbus = use_dbus

1522

self.gnutls_priority = gnutls_priority

1523

IPv6_TCPServer.__init__(self, server_address,

1524

RequestHandlerClass,

1525

interface = interface,

1526

use_ipv6 = use_ipv6)

1527

def server_activate(self):

1528

if self.enabled:

1529

return socketserver.TCPServer.server_activate(self)

1530

def enable(self):

1531

self.enabled = True

1532

def add_pipe(self, parent_pipe):

1533

# Call "handle_ipc" for both data and EOF events

1534

gobject.io_add_watch(parent_pipe.fileno(),

1535

gobject.IO_IN | gobject.IO_HUP,

1536

functools.partial(self.handle_ipc,

1537

parent_pipe = parent_pipe))

1538

1539

def handle_ipc(self, source, condition, parent_pipe=None,

1540

client_object=None):

1541

condition_names = {

1542

gobject.IO_IN: "IN", # There is data to read.

1543

gobject.IO_OUT: "OUT", # Data can be written (without

1544

# blocking).

1545

gobject.IO_PRI: "PRI", # There is urgent data to read.

1546

gobject.IO_ERR: "ERR", # Error condition.

1547

gobject.IO_HUP: "HUP" # Hung up (the connection has been

1548

# broken, usually for pipes and

1549

# sockets).

1550

}

1551

conditions_string = ' | '.join(name

1552

for cond, name in

1553

condition_names.iteritems()

1554

if cond & condition)

1555

# error or the other end of multiprocessing.Pipe has closed

1556

if condition & (gobject.IO_ERR | condition & gobject.IO_HUP):

1557

return False

1558

1559

# Read a request from the child

1560

request = parent_pipe.recv()

1561

command = request[0]

1562

1563

if command == 'init':

1564

fpr = request[1]

1565

address = request[2]

1566

1567

for c in self.clients:

1568

if c.fingerprint == fpr:

1569

client = c

1570

break

1571

else:

1572

logger.info("Client not found for fingerprint: %s, ad"

1573

"dress: %s", fpr, address)

1574

if self.use_dbus:

1575

# Emit D-Bus signal

1576

mandos_dbus_service.ClientNotFound(fpr, address[0])

1577

parent_pipe.send(False)

1578

return False

1579

1580

gobject.io_add_watch(parent_pipe.fileno(),

1581

gobject.IO_IN | gobject.IO_HUP,

1582

functools.partial(self.handle_ipc,

1583

parent_pipe = parent_pipe,

1584

client_object = client))

1585

parent_pipe.send(True)

1586

# remove the old hook in favor of the new above hook on same fileno

1587

return False

1588

if command == 'funcall':

1589

funcname = request[1]

1590

args = request[2]

1591

kwargs = request[3]

1592

1593

parent_pipe.send(('data', getattr(client_object, funcname)(*args, **kwargs)))

1594

1595

if command == 'getattr':

1596

attrname = request[1]

1597

if callable(client_object.__getattribute__(attrname)):

1598

parent_pipe.send(('function',))

1599

else:

1600

parent_pipe.send(('data', client_object.__getattribute__(attrname)))

1601

1602

if command == 'setattr':

1603

attrname = request[1]

1604

value = request[2]

1605

setattr(client_object, attrname, value)

1606

1607

return True

1608

1609

1610

def string_to_delta(interval):

1611

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

1612

1613

>>> string_to_delta('7d')

1614

datetime.timedelta(7)

1615

>>> string_to_delta('60s')

1616

datetime.timedelta(0, 60)

1617

>>> string_to_delta('60m')

1618

datetime.timedelta(0, 3600)

1619

>>> string_to_delta('24h')

1620

datetime.timedelta(1)

1621

>>> string_to_delta('1w')

1622

datetime.timedelta(7)

1623

>>> string_to_delta('5m 30s')

1624

datetime.timedelta(0, 330)

1625

"""

1626

timevalue = datetime.timedelta(0)

1627

for s in interval.split():

1628

try:

1629

suffix = unicode(s[-1])

1630

value = int(s[:-1])

1631

if suffix == "d":

1632

delta = datetime.timedelta(value)

1633

elif suffix == "s":

1634

delta = datetime.timedelta(0, value)

1635

elif suffix == "m":

1636

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

1637

elif suffix == "h":

1638

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

1639

elif suffix == "w":

1640

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

1641

else:

1642

raise ValueError("Unknown suffix %r" % suffix)

1643

except (ValueError, IndexError) as e:

1644

raise ValueError(*(e.args))

1645

timevalue += delta

1646

return timevalue

1647

1648

1649

def if_nametoindex(interface):

1650

"""Call the C function if_nametoindex(), or equivalent

1651

1652

Note: This function cannot accept a unicode string."""

1653

global if_nametoindex

1654

try:

1655

if_nametoindex = (ctypes.cdll.LoadLibrary

1656

(ctypes.util.find_library("c"))

1657

.if_nametoindex)

1658

except (OSError, AttributeError):

1659

logger.warning("Doing if_nametoindex the hard way")

1660

def if_nametoindex(interface):

1661

"Get an interface index the hard way, i.e. using fcntl()"

1662

SIOCGIFINDEX = 0x8933 # From /usr/include/linux/sockios.h

1663

with contextlib.closing(socket.socket()) as s:

1664

ifreq = fcntl.ioctl(s, SIOCGIFINDEX,

1665

struct.pack(str("16s16x"),

1666

interface))

1667

interface_index = struct.unpack(str("I"),

1668

ifreq[16:20])[0]

1669

return interface_index

1670

return if_nametoindex(interface)

1671

1672

1673

def daemon(nochdir = False, noclose = False):

1674

"""See daemon(3). Standard BSD Unix function.

1675

1676

This should really exist as os.daemon, but it doesn't (yet)."""

1677

if os.fork():

1678

sys.exit()

1679

os.setsid()

1680

if not nochdir:

1681

os.chdir("/")

1682

if os.fork():

1683

sys.exit()

1684

if not noclose:

1685

# Close all standard open file descriptors

1686

null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)

1687

if not stat.S_ISCHR(os.fstat(null).st_mode):

1688

raise OSError(errno.ENODEV,

1689

"%s not a character device"

1690

% os.path.devnull)

1691

os.dup2(null, sys.stdin.fileno())

1692

os.dup2(null, sys.stdout.fileno())

1693

os.dup2(null, sys.stderr.fileno())

1694

if null > 2:

1695

os.close(null)

1696

1697

1698

def main():

1699

1700

##################################################################

1701

# Parsing of options, both command line and config file

1702

1703

parser = argparse.ArgumentParser()

1704

parser.add_argument("-v", "--version", action="version",

1705

version = "%%(prog)s %s" % version,

1706

help="show version number and exit")

1707

parser.add_argument("-i", "--interface", metavar="IF",

1708

help="Bind to interface IF")

1709

parser.add_argument("-a", "--address",

1710

help="Address to listen for requests on")

1711

parser.add_argument("-p", "--port", type=int,

1712

help="Port number to receive requests on")

1713

parser.add_argument("--check", action="store_true",

1714

help="Run self-test")

1715

parser.add_argument("--debug", action="store_true",

1716

help="Debug mode; run in foreground and log"

1717

" to terminal")

1718

parser.add_argument("--debuglevel", metavar="LEVEL",

1719

help="Debug level for stdout output")

1720

parser.add_argument("--priority", help="GnuTLS"

1721

" priority string (see GnuTLS documentation)")

1722

parser.add_argument("--servicename",

1723

metavar="NAME", help="Zeroconf service name")

1724

parser.add_argument("--configdir",

1725

default="/etc/mandos", metavar="DIR",

1726

help="Directory to search for configuration"

1727

" files")

1728

parser.add_argument("--no-dbus", action="store_false",

1729

dest="use_dbus", help="Do not provide D-Bus"

1730

" system bus interface")

1731

parser.add_argument("--no-ipv6", action="store_false",

1732

dest="use_ipv6", help="Do not use IPv6")

1733

options = parser.parse_args()

1734

1735

if options.check:

1736

import doctest

1737

doctest.testmod()

1738

sys.exit()

1739

1740

# Default values for config file for server-global settings

1741

server_defaults = { "interface": "",

1742

"address": "",

1743

"port": "",

1744

"debug": "False",

1745

"priority":

1746

"SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",

1747

"servicename": "Mandos",

1748

"use_dbus": "True",

1749

"use_ipv6": "True",

1750

"debuglevel": "",

1751

}

1752

1753

# Parse config file for server-global settings

1754

server_config = configparser.SafeConfigParser(server_defaults)

1755

del server_defaults

1756

server_config.read(os.path.join(options.configdir,

1757

"mandos.conf"))

1758

# Convert the SafeConfigParser object to a dict

1759

server_settings = server_config.defaults()

1760

# Use the appropriate methods on the non-string config options

1761

for option in ("debug", "use_dbus", "use_ipv6"):

1762

server_settings[option] = server_config.getboolean("DEFAULT",

1763

option)

1764

if server_settings["port"]:

1765

server_settings["port"] = server_config.getint("DEFAULT",

1766

"port")

1767

del server_config

1768

1769

# Override the settings from the config file with command line

1770

# options, if set.

1771

for option in ("interface", "address", "port", "debug",

1772

"priority", "servicename", "configdir",

1773

"use_dbus", "use_ipv6", "debuglevel"):

1774

value = getattr(options, option)

1775

if value is not None:

1776

server_settings[option] = value

1777

del options

1778

# Force all strings to be unicode

1779

for option in server_settings.keys():

1780

if type(server_settings[option]) is str:

1781

server_settings[option] = unicode(server_settings[option])

1782

# Now we have our good server settings in "server_settings"

1783

1784

##################################################################

1785

1786

# For convenience

1787

debug = server_settings["debug"]

1788

debuglevel = server_settings["debuglevel"]

1789

use_dbus = server_settings["use_dbus"]

1790

use_ipv6 = server_settings["use_ipv6"]

1791

1792

if server_settings["servicename"] != "Mandos":

1793

syslogger.setFormatter(logging.Formatter

1794

('Mandos (%s) [%%(process)d]:'

1795

' %%(levelname)s: %%(message)s'

1796

% server_settings["servicename"]))

1797

1798

# Parse config file with clients

1799

client_defaults = { "timeout": "1h",

1800

"interval": "5m",

1801

"checker": "fping -q -- %%(host)s",

1802

"host": "",

1803

"approval_delay": "0s",

1804

"approval_duration": "1s",

1805

}

1806

client_config = configparser.SafeConfigParser(client_defaults)

1807

client_config.read(os.path.join(server_settings["configdir"],

1808

"clients.conf"))

1809

1810

global mandos_dbus_service

1811

mandos_dbus_service = None

1812

1813

tcp_server = MandosServer((server_settings["address"],

1814

server_settings["port"]),

1815

ClientHandler,

1816

interface=(server_settings["interface"]

1817

or None),

1818

use_ipv6=use_ipv6,

1819

gnutls_priority=

1820

server_settings["priority"],

1821

use_dbus=use_dbus)

1822

if not debug:

1823

pidfilename = "/var/run/mandos.pid"

1824

try:

1825

pidfile = open(pidfilename, "w")

1826

except IOError:

1827

logger.error("Could not open file %r", pidfilename)

1828

1829

try:

1830

uid = pwd.getpwnam("_mandos").pw_uid

1831

gid = pwd.getpwnam("_mandos").pw_gid

1832

except KeyError:

1833

try:

1834

uid = pwd.getpwnam("mandos").pw_uid

1835

gid = pwd.getpwnam("mandos").pw_gid

1836

except KeyError:

1837

try:

1838

uid = pwd.getpwnam("nobody").pw_uid

1839

gid = pwd.getpwnam("nobody").pw_gid

1840

except KeyError:

1841

uid = 65534

1842

gid = 65534

1843

try:

1844

os.setgid(gid)

1845

os.setuid(uid)

1846

except OSError as error:

1847

if error[0] != errno.EPERM:

1848

raise error

1849

1850

if not debug and not debuglevel:

1851

syslogger.setLevel(logging.WARNING)

1852

console.setLevel(logging.WARNING)

1853

if debuglevel:

1854

level = getattr(logging, debuglevel.upper())

1855

syslogger.setLevel(level)

1856

console.setLevel(level)

1857

1858

if debug:

1859

# Enable all possible GnuTLS debugging

1860

1861

# "Use a log level over 10 to enable all debugging options."

1862

# - GnuTLS manual

1863

gnutls.library.functions.gnutls_global_set_log_level(11)

1864

1865

@gnutls.library.types.gnutls_log_func

1866

def debug_gnutls(level, string):

1867

logger.debug("GnuTLS: %s", string[:-1])

1868

1869

(gnutls.library.functions

1870

.gnutls_global_set_log_function(debug_gnutls))

1871

1872

# Redirect stdin so all checkers get /dev/null

1873

null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)

1874

os.dup2(null, sys.stdin.fileno())

1875

if null > 2:

1876

os.close(null)

1877

else:

1878

# No console logging

1879

logger.removeHandler(console)

1880

1881

# Need to fork before connecting to D-Bus

1882

if not debug:

1883

# Close all input and output, do double fork, etc.

1884

daemon()

1885

1886

global main_loop

1887

# From the Avahi example code

1888

DBusGMainLoop(set_as_default=True )

1889

main_loop = gobject.MainLoop()

1890

bus = dbus.SystemBus()

1891

# End of Avahi example code

1892

if use_dbus:

1893

try:

1894

bus_name = dbus.service.BusName("se.bsnet.fukt.Mandos",

1895

bus, do_not_queue=True)

1896

except dbus.exceptions.NameExistsException as e:

1897

logger.error(unicode(e) + ", disabling D-Bus")

1898

use_dbus = False

1899

server_settings["use_dbus"] = False

1900

tcp_server.use_dbus = False

1901

protocol = avahi.PROTO_INET6 if use_ipv6 else avahi.PROTO_INET

1902

service = AvahiService(name = server_settings["servicename"],

1903

servicetype = "_mandos._tcp",

1904

protocol = protocol, bus = bus)

1905

if server_settings["interface"]:

1906

service.interface = (if_nametoindex

1907

(str(server_settings["interface"])))

1908

1909

global multiprocessing_manager

1910

multiprocessing_manager = multiprocessing.Manager()

1911

1912

client_class = Client

1913

if use_dbus:

1914

client_class = functools.partial(ClientDBus, bus = bus)

1915

def client_config_items(config, section):

1916

special_settings = {

1917

"approved_by_default":

1918

lambda: config.getboolean(section,

1919

"approved_by_default"),

1920

}

1921

for name, value in config.items(section):

1922

try:

1923

yield (name, special_settings[name]())

1924

except KeyError:

1925

yield (name, value)

1926

1927

tcp_server.clients.update(set(

1928

client_class(name = section,

1929

config= dict(client_config_items(

1930

client_config, section)))

1931

for section in client_config.sections()))

1932

if not tcp_server.clients:

1933

logger.warning("No clients defined")

1934

1935

if not debug:

1936

try:

1937

with pidfile:

1938

pid = os.getpid()

1939

pidfile.write(str(pid) + "\n".encode("utf-8"))

1940

del pidfile

1941

except IOError:

1942

logger.error("Could not write to file %r with PID %d",

1943

pidfilename, pid)

1944

except NameError:

1945

# "pidfile" was never created

1946

pass

1947

del pidfilename

1948

1949

signal.signal(signal.SIGINT, signal.SIG_IGN)

1950

1951

signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())

1952

signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())

1953

1954

if use_dbus:

1955

class MandosDBusService(dbus.service.Object):

1956

"""A D-Bus proxy object"""

1957

def __init__(self):

1958

dbus.service.Object.__init__(self, bus, "/")

1959

_interface = "se.bsnet.fukt.Mandos"

1960

1961

@dbus.service.signal(_interface, signature="o")

1962

def ClientAdded(self, objpath):

1963

"D-Bus signal"

1964

pass

1965

1966

@dbus.service.signal(_interface, signature="ss")

1967

def ClientNotFound(self, fingerprint, address):

1968

"D-Bus signal"

1969

pass

1970

1971

@dbus.service.signal(_interface, signature="os")

1972

def ClientRemoved(self, objpath, name):

1973

"D-Bus signal"

1974

pass

1975

1976

@dbus.service.method(_interface, out_signature="ao")

1977

def GetAllClients(self):

1978

"D-Bus method"

1979

return dbus.Array(c.dbus_object_path

1980

for c in tcp_server.clients)

1981

1982

@dbus.service.method(_interface,

1983

out_signature="a{oa{sv}}")

1984

def GetAllClientsWithProperties(self):

1985

"D-Bus method"

1986

return dbus.Dictionary(

1987

((c.dbus_object_path, c.GetAll(""))

1988

for c in tcp_server.clients),

1989

signature="oa{sv}")

1990

1991

@dbus.service.method(_interface, in_signature="o")

1992

def RemoveClient(self, object_path):

1993

"D-Bus method"

1994

for c in tcp_server.clients:

1995

if c.dbus_object_path == object_path:

1996

tcp_server.clients.remove(c)

1997

c.remove_from_connection()

1998

# Don't signal anything except ClientRemoved

1999

c.disable(quiet=True)

2000

# Emit D-Bus signal

2001

self.ClientRemoved(object_path, c.name)

2002

return

2003

raise KeyError(object_path)

2004

2005

del _interface

2006

2007

mandos_dbus_service = MandosDBusService()

2008

2009

def cleanup():

2010

"Cleanup function; run on exit"

2011

service.cleanup()

2012

2013

while tcp_server.clients:

2014

client = tcp_server.clients.pop()

2015

if use_dbus:

2016

client.remove_from_connection()

2017

client.disable_hook = None

2018

# Don't signal anything except ClientRemoved

2019

client.disable(quiet=True)

2020

if use_dbus:

2021

# Emit D-Bus signal

2022

mandos_dbus_service.ClientRemoved(client.dbus_object_path,

2023

client.name)

2024

2025

atexit.register(cleanup)

2026

2027

for client in tcp_server.clients:

2028

if use_dbus:

2029

# Emit D-Bus signal

2030

mandos_dbus_service.ClientAdded(client.dbus_object_path)

2031

client.enable()

2032

2033

tcp_server.enable()

2034

tcp_server.server_activate()

2035

2036

# Find out what port we got

2037

service.port = tcp_server.socket.getsockname()[1]

2038

if use_ipv6:

2039

logger.info("Now listening on address %r, port %d,"

2040

" flowinfo %d, scope_id %d"

2041

% tcp_server.socket.getsockname())

2042

else: # IPv4

2043

logger.info("Now listening on address %r, port %d"

2044

% tcp_server.socket.getsockname())

2045

2046

#service.interface = tcp_server.socket.getsockname()[3]

2047

2048

try:

2049

# From the Avahi example code

2050

try:

2051

service.activate()

2052

except dbus.exceptions.DBusException as error:

2053

logger.critical("DBusException: %s", error)

2054

cleanup()

2055

sys.exit(1)

2056

# End of Avahi example code

2057

2058

gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,

2059

lambda *args, **kwargs:

2060

(tcp_server.handle_request

2061

(*args[2:], **kwargs) or True))

2062

2063

logger.debug("Starting main loop")

2064

main_loop.run()

2065

except AvahiError as error:

2066

logger.critical("AvahiError: %s", error)

2067

cleanup()

2068

sys.exit(1)

2069

except KeyboardInterrupt:

2070

if debug:

2071

print("", file=sys.stderr)

2072

logger.debug("Server received KeyboardInterrupt")

2073

logger.debug("Server exiting")

2074

# Must run before the D-Bus bus name gets deregistered

2075

cleanup()

2076

2077

if __name__ == '__main__':

2078

main()