blob: 064653a3d5720401a36e13cc38f22902c4658abc [file] [log] [blame]
# Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
import logging
import os
import re
from xml.dom import minidom
from autotest_lib.client.bin import test
from autotest_lib.client.common_lib import error
class security_DbusOwners(test.test):
"""Enforces a whitelist of known, allowed Dbus interfaces owned by chronos.
version = 1
_DBUS_CONFIG_DIR = '/etc/dbus-1/system.d/'
def load_baseline(self):
"""Return a list of interface names to be owned by chronos."""
bfile = open(os.path.join(self.bindir, 'baseline'))
baseline_data =
baseline_set = set(baseline_data.splitlines())
return baseline_set
def fetch_chronos_owned_interfaces(self):
For every DBus interface XML, look for <policy user="chronos"> sections
containing <allow own="InterfaceName">. Return the list of interfaces
owned by chronos.
chronos_owned = []
for root, dirs, files in os.walk(self._DBUS_CONFIG_DIR):
for filename in files:
# Skip cruft like dotfiles.
if not'^[^.].*\.conf$', filename):
logging.debug('Skipping %s', filename)
logging.debug('Parsing %s', filename)
xmldoc = minidom.parse(os.path.join(root,filename))
policies = xmldoc.getElementsByTagName('policy')
for policy in policies:
if (policy.hasAttribute('user') and
policy.getAttribute('user') == 'chronos'):
allows = policy.getElementsByTagName('allow')
for allow in allows:
if allow.hasAttribute('own'):
return set(chronos_owned)
def run_once(self):
Enumerate all the DBus interfaces owned by chronos.
Fail if they're not included in the expected set.
observed_set = self.fetch_chronos_owned_interfaces()
baseline_set = self.load_baseline()
# We log but don't fail if we find missing interfaces.
missing_ifaces = baseline_set.difference(observed_set)
if len(missing_ifaces) > 0:
for iface in missing_ifaces:
logging.error('Missing chronos-owned interface %s', iface)
# We fail if we find new interfaces.
new_ifaces = observed_set.difference(baseline_set)
if len(new_ifaces) > 0:
message = 'New chronos-owned interface(s): ' + ', '.join(new_ifaces)
raise error.TestFail(message)