charm-neutron-gateway/hooks/charmhelpers/contrib/hardening/audits/apache.py

106 lines
3.6 KiB
Python

# Copyright 2016 Canonical Limited.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import re
import subprocess
import six
from charmhelpers.core.hookenv import (
log,
INFO,
ERROR,
)
from charmhelpers.contrib.hardening.audits import BaseAudit
class DisabledModuleAudit(BaseAudit):
"""Audits Apache2 modules.
Determines if the apache2 modules are enabled. If the modules are enabled
then they are removed in the ensure_compliance.
"""
def __init__(self, modules):
if modules is None:
self.modules = []
elif isinstance(modules, six.string_types):
self.modules = [modules]
else:
self.modules = modules
def ensure_compliance(self):
"""Ensures that the modules are not loaded."""
if not self.modules:
return
try:
loaded_modules = self._get_loaded_modules()
non_compliant_modules = []
for module in self.modules:
if module in loaded_modules:
log("Module '%s' is enabled but should not be." %
(module), level=INFO)
non_compliant_modules.append(module)
if len(non_compliant_modules) == 0:
return
for module in non_compliant_modules:
self._disable_module(module)
self._restart_apache()
except subprocess.CalledProcessError as e:
log('Error occurred auditing apache module compliance. '
'This may have been already reported. '
'Output is: %s' % e.output, level=ERROR)
@staticmethod
def _get_loaded_modules():
"""Returns the modules which are enabled in Apache."""
output = subprocess.check_output(['apache2ctl', '-M'])
if six.PY3:
output = output.decode('utf-8')
modules = []
for line in output.splitlines():
# Each line of the enabled module output looks like:
# module_name (static|shared)
# Plus a header line at the top of the output which is stripped
# out by the regex.
matcher = re.search(r'^ (\S*)_module (\S*)', line)
if matcher:
modules.append(matcher.group(1))
return modules
@staticmethod
def _disable_module(module):
"""Disables the specified module in Apache."""
try:
subprocess.check_call(['a2dismod', module])
except subprocess.CalledProcessError as e:
# Note: catch error here to allow the attempt of disabling
# multiple modules in one go rather than failing after the
# first module fails.
log('Error occurred disabling module %s. '
'Output is: %s' % (module, e.output), level=ERROR)
@staticmethod
def _restart_apache():
"""Restarts the apache process"""
subprocess.check_output(['service', 'apache2', 'restart'])
@staticmethod
def is_ssl_enabled():
"""Check if SSL module is enabled or not"""
return 'ssl' in DisabledModuleAudit._get_loaded_modules()