deb-heat/heat/common/policy.py
Jamie Lennox 528945425e Use to_policy_values from context for policy
The oslo.context to_policy_values provide the standard arguments that
should be passed to oslo.policy for enforcement. By using these values
heat will automatically gain support for new things like
is_admin_project as they are supported by oslo_context.

Because previously the whole to_dict was passed to policy enforcement we
are actually removing a whole bunch of options that could be used in
policy enforcement - however from a practical perspective i'm not sure
anyone would have used them.

Closes-Bug: #1602081
Change-Id: I244ed767e2077cf43d55104779484b64bd28c85f
2016-07-12 13:42:00 +10:00

116 lines
4.4 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.
# Based on glance/api/policy.py
"""Policy Engine For Heat."""
from oslo_config import cfg
from oslo_log import log as logging
from oslo_policy import policy
import six
from heat.common import exception
CONF = cfg.CONF
LOG = logging.getLogger(__name__)
DEFAULT_RULES = policy.Rules.from_dict({'default': '!'})
DEFAULT_RESOURCE_RULES = policy.Rules.from_dict({'default': '@'})
class Enforcer(object):
"""Responsible for loading and enforcing rules."""
def __init__(self, scope='heat', exc=exception.Forbidden,
default_rule=DEFAULT_RULES['default'], policy_file=None):
self.scope = scope
self.exc = exc
self.default_rule = default_rule
self.enforcer = policy.Enforcer(
CONF, default_rule=default_rule, policy_file=policy_file)
def set_rules(self, rules, overwrite=True):
"""Create a new Rules object based on the provided dict of rules."""
rules_obj = policy.Rules(rules, self.default_rule)
self.enforcer.set_rules(rules_obj, overwrite)
def load_rules(self, force_reload=False):
"""Set the rules found in the json file on disk."""
self.enforcer.load_rules(force_reload)
def _check(self, context, rule, target, exc, *args, **kwargs):
"""Verifies that the action is valid on the target in this context.
:param context: Heat request context
:param rule: String representing the action to be checked
:param target: Dictionary representing the object of the action.
:raises: self.exc (defaults to heat.common.exception.Forbidden)
:returns: A non-False value if access is allowed.
"""
do_raise = False if not exc else True
credentials = context.to_policy_values()
return self.enforcer.enforce(rule, target, credentials,
do_raise, exc=exc, *args, **kwargs)
def enforce(self, context, action, scope=None, target=None):
"""Verifies that the action is valid on the target in this context.
:param context: Heat request context
:param action: String representing the action to be checked
:param target: Dictionary representing the object of the action.
:raises: self.exc (defaults to heat.common.exception.Forbidden)
:returns: A non-False value if access is allowed.
"""
_action = '%s:%s' % (scope or self.scope, action)
_target = target or {}
return self._check(context, _action, _target, self.exc, action=action)
def check_is_admin(self, context):
"""Whether or not roles contains 'admin' role according to policy.json.
:param context: Heat request context
:returns: A non-False value if the user is admin according to policy
"""
return self._check(context, 'context_is_admin', target={}, exc=None)
class ResourceEnforcer(Enforcer):
def __init__(self, default_rule=DEFAULT_RESOURCE_RULES['default'],
**kwargs):
super(ResourceEnforcer, self).__init__(
default_rule=default_rule, **kwargs)
def enforce(self, context, res_type, scope=None, target=None):
# NOTE(pas-ha): try/except just to log the exception
try:
result = super(ResourceEnforcer, self).enforce(
context, res_type,
scope=scope or 'resource_types',
target=target)
except self.exc as ex:
LOG.info(six.text_type(ex))
raise
if not result:
if self.exc:
raise self.exc(action=res_type)
else:
return result
def enforce_stack(self, stack, scope=None, target=None):
for res in stack.resources.values():
self.enforce(stack.context, res.type(), scope=scope, target=target)