19f9a4bbd4
This adds the basic framework for registering and using default policy rules. Rules should be defined and returned from a module in nova/policies/, and then added to the list in nova/policies/__init__.py. A new context.can() method has been added for policy enforcement of registered rules. It has the same parameters as the enforce() method currently being used. To establish the full pattern for usage the policy checks in the servers API module have been registered and converted to the new usage. Now that some policy checks are registered they're being used properly by tests. Some tests have been updated so that the instance project_id matches the context project_id in order to pass the 'admin_or_owner' check. Change-Id: I71b3d1233255125cb280a000b990329f5b03fdfd Partially-Implements: bp policy-in-code
199 lines
7.1 KiB
Python
199 lines
7.1 KiB
Python
# Copyright (c) 2011 OpenStack Foundation
|
|
# 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.
|
|
|
|
"""Policy Engine For Nova."""
|
|
|
|
import logging
|
|
|
|
from oslo_config import cfg
|
|
from oslo_policy import policy
|
|
from oslo_utils import excutils
|
|
|
|
from nova import exception
|
|
from nova.i18n import _LE
|
|
from nova import policies
|
|
|
|
|
|
CONF = cfg.CONF
|
|
LOG = logging.getLogger(__name__)
|
|
_ENFORCER = None
|
|
|
|
|
|
def reset():
|
|
global _ENFORCER
|
|
if _ENFORCER:
|
|
_ENFORCER.clear()
|
|
_ENFORCER = None
|
|
|
|
|
|
def init(policy_file=None, rules=None, default_rule=None, use_conf=True):
|
|
"""Init an Enforcer class.
|
|
|
|
:param policy_file: Custom policy file to use, if none is specified,
|
|
`CONF.policy_file` will be used.
|
|
:param rules: Default dictionary / Rules to use. It will be
|
|
considered just in the first instantiation.
|
|
:param default_rule: Default rule to use, CONF.default_rule will
|
|
be used if none is specified.
|
|
:param use_conf: Whether to load rules from config file.
|
|
"""
|
|
|
|
global _ENFORCER
|
|
if not _ENFORCER:
|
|
_ENFORCER = policy.Enforcer(CONF,
|
|
policy_file=policy_file,
|
|
rules=rules,
|
|
default_rule=default_rule,
|
|
use_conf=use_conf)
|
|
register_rules(_ENFORCER)
|
|
|
|
|
|
def set_rules(rules, overwrite=True, use_conf=False):
|
|
"""Set rules based on the provided dict of rules.
|
|
|
|
:param rules: New rules to use. It should be an instance of dict.
|
|
:param overwrite: Whether to overwrite current rules or update them
|
|
with the new rules.
|
|
:param use_conf: Whether to reload rules from config file.
|
|
"""
|
|
|
|
init(use_conf=False)
|
|
_ENFORCER.set_rules(rules, overwrite, use_conf)
|
|
|
|
|
|
# TODO(alaski): All users of this method should move over to authorize() as
|
|
# policies are registered and ultimately this should be removed.
|
|
def enforce(context, action, target, do_raise=True, exc=None):
|
|
"""Verifies that the action is valid on the target in this context.
|
|
|
|
:param context: nova context
|
|
:param action: string representing the action to be checked
|
|
this should be colon separated for clarity.
|
|
i.e. ``compute:create_instance``,
|
|
``compute:attach_volume``,
|
|
``volume:attach_volume``
|
|
: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. ``{'project_id': context.project_id}``
|
|
:param do_raise: if True (the default), raises PolicyNotAuthorized;
|
|
if False, returns False
|
|
|
|
:raises nova.exception.PolicyNotAuthorized: if verification fails
|
|
and do_raise is True.
|
|
|
|
:return: returns a non-False value (not necessarily "True") if
|
|
authorized, and the exact value False if not authorized and
|
|
do_raise is False.
|
|
"""
|
|
init()
|
|
credentials = context.to_dict()
|
|
if not exc:
|
|
exc = exception.PolicyNotAuthorized
|
|
try:
|
|
result = _ENFORCER.enforce(action, target, credentials,
|
|
do_raise=do_raise, exc=exc, action=action)
|
|
except Exception:
|
|
credentials.pop('auth_token', None)
|
|
with excutils.save_and_reraise_exception():
|
|
LOG.debug('Policy check for %(action)s failed with credentials '
|
|
'%(credentials)s',
|
|
{'action': action, 'credentials': credentials})
|
|
return result
|
|
|
|
|
|
def authorize(context, action, target, do_raise=True, exc=None):
|
|
"""Verifies that the action is valid on the target in this context.
|
|
|
|
:param context: nova context
|
|
:param action: string representing the action to be checked
|
|
this should be colon separated for clarity.
|
|
i.e. ``compute:create_instance``,
|
|
``compute:attach_volume``,
|
|
``volume:attach_volume``
|
|
: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. ``{'project_id': context.project_id}``
|
|
:param do_raise: if True (the default), raises PolicyNotAuthorized;
|
|
if False, returns False
|
|
:param exc: Class of the exception to raise if the check fails.
|
|
Any remaining arguments passed to :meth:`enforce` (both
|
|
positional and keyword arguments) will be passed to
|
|
the exception class. If not specified,
|
|
:class:`PolicyNotAuthorized` will be used.
|
|
|
|
:raises nova.exception.PolicyNotAuthorized: if verification fails
|
|
and do_raise is True. Or if 'exc' is specified it will raise an
|
|
exception of that type.
|
|
|
|
:return: returns a non-False value (not necessarily "True") if
|
|
authorized, and the exact value False if not authorized and
|
|
do_raise is False.
|
|
"""
|
|
init()
|
|
credentials = context.to_dict()
|
|
if not exc:
|
|
exc = exception.PolicyNotAuthorized
|
|
try:
|
|
result = _ENFORCER.authorize(action, target, credentials,
|
|
do_raise=do_raise, exc=exc, action=action)
|
|
except policy.PolicyNotRegistered:
|
|
with excutils.save_and_reraise_exception():
|
|
LOG.exception(_LE('Policy not registered'))
|
|
except Exception:
|
|
credentials.pop('auth_token', None)
|
|
with excutils.save_and_reraise_exception():
|
|
LOG.debug('Policy check for %(action)s failed with credentials '
|
|
'%(credentials)s',
|
|
{'action': action, 'credentials': credentials})
|
|
return result
|
|
|
|
|
|
def check_is_admin(context):
|
|
"""Whether or not roles contains 'admin' role according to policy setting.
|
|
|
|
"""
|
|
|
|
init()
|
|
# the target is user-self
|
|
credentials = context.to_dict()
|
|
target = credentials
|
|
return _ENFORCER.enforce('context_is_admin', target, credentials)
|
|
|
|
|
|
@policy.register('is_admin')
|
|
class IsAdminCheck(policy.Check):
|
|
"""An explicit check for is_admin."""
|
|
|
|
def __init__(self, kind, match):
|
|
"""Initialize the check."""
|
|
|
|
self.expected = (match.lower() == 'true')
|
|
|
|
super(IsAdminCheck, self).__init__(kind, str(self.expected))
|
|
|
|
def __call__(self, target, creds, enforcer):
|
|
"""Determine whether is_admin matches the requested value."""
|
|
|
|
return creds['is_admin'] == self.expected
|
|
|
|
|
|
def get_rules():
|
|
if _ENFORCER:
|
|
return _ENFORCER.rules
|
|
|
|
|
|
def register_rules(enforcer):
|
|
enforcer.register_defaults(policies.list_rules())
|