Files
keystone/keystone/policy/backends/rules.py
Joe Heck c74009025f tweaking docs to fix link to wiki Keystone page
updated docstrings to remove two errors
reformatted front page header to be consistent
added links to autogenerated python documentation

Change-Id: I59fddc12ff458bbd0102a40d4d85903ab6bd6394
2012-11-10 15:57:59 -08:00

111 lines
3.2 KiB
Python

# vim: tabstop=4 shiftwidth=4 softtabstop=4
# Copyright (c) 2011 OpenStack, LLC.
# All Rights Reserved.
#
# 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.
"""Rules-based Policy Engine."""
import os.path
from keystone.common import logging
from keystone.common import policy as common_policy
from keystone.common import utils
from keystone import config
from keystone import exception
from keystone.openstack.common import cfg
from keystone import policy
policy_opts = [
cfg.StrOpt('policy_file',
default='policy.json',
help=_('JSON file representing policy')),
cfg.StrOpt('policy_default_rule',
default='default',
help=_('Rule checked when requested rule is not found')),
]
CONF = config.CONF
CONF.register_opts(policy_opts)
LOG = logging.getLogger(__name__)
_POLICY_PATH = None
_POLICY_CACHE = {}
def reset():
global _POLICY_PATH
global _POLICY_CACHE
_POLICY_PATH = None
_POLICY_CACHE = {}
common_policy.reset()
def init():
global _POLICY_PATH
global _POLICY_CACHE
if not _POLICY_PATH:
_POLICY_PATH = CONF.policy_file
if not os.path.exists(_POLICY_PATH):
_POLICY_PATH = CONF.find_file(_POLICY_PATH)
utils.read_cached_file(_POLICY_PATH,
_POLICY_CACHE,
reload_func=_set_brain)
def _set_brain(data):
default_rule = CONF.policy_default_rule
common_policy.set_brain(common_policy.HttpBrain.load_json(data,
default_rule))
def enforce(credentials, action, target):
"""Verifies that the action is valid on the target in this context.
:param credentials: user credentials
:param action: string representing the action to be checked, which
should be colon separated for clarity.
:param target: dictionary representing the object of the action
for object creation this should be a dictionary
representing the location of the object e.g.
{'tenant_id': object.tenant_id}
:raises: `exception.Forbidden` if verification fails.
Actions should be colon separated for clarity. For example:
* compute:create_instance
* compute:attach_volume
* volume:attach_volume
"""
init()
match_list = ('rule:%s' % action,)
try:
common_policy.enforce(match_list, target, credentials)
except common_policy.NotAuthorized:
raise exception.ForbiddenAction(action=action)
class Policy(policy.Driver):
def enforce(self, credentials, action, target):
LOG.debug('enforce %s: %s', action, credentials)
enforce(credentials, action, target)