#
# 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 Horizon"""
import logging
import os.path
from django.conf import settings
from openstack_auth import utils as auth_utils
from oslo_config import cfg
from oslo_policy import policy
LOG = logging.getLogger(__name__)
CONF = cfg.CONF
# Policy Enforcer has been updated to take in a policy directory
# as a config option. However, the default value in is set to
# ['policy.d'] which causes the code to break. Set the default
# value to empty list for now.
CONF.policy_dirs = []
_ENFORCER = None
_BASE_PATH = getattr(settings, 'POLICY_FILES_PATH', '')
def _get_enforcer():
global _ENFORCER
if not _ENFORCER:
_ENFORCER = {}
policy_files = getattr(settings, 'POLICY_FILES', {})
for service in policy_files.keys():
policy_path = os.path.join(_BASE_PATH,
policy_files[service])
if os.path.isfile(policy_path):
LOG.debug("adding enforcer for service: %s" % service)
enforcer = policy.Enforcer(CONF)
CONF.oslo_policy.policy_dirs = []
enforcer.policy_path = policy_path
_ENFORCER[service] = enforcer
else:
LOG.warn("policy file for service: %s not found at %s" %
(service, policy_path))
return _ENFORCER
[docs]def reset():
global _ENFORCER
_ENFORCER = None
[docs]def check(actions, request, target=None):
"""Check user permission.
Check if the user has permission to the action according
to policy setting.
:param actions: list of scope and action to do policy checks on,
the composition of which is (scope, action)
* scope: service type managing the policy for action
* 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
for a policy action that requires a single action, actions
should look like
| "(("compute", "compute:create_instance"),)"
for a multiple action check, actions should look like
| "(("identity", "identity:list_users"),
| ("identity", "identity:list_roles"))"
:param request: django http request object. If not specified, credentials
must be passed.
: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': object.project_id}
:returns: boolean if the user has permission or not for the actions.
"""
if target is None:
target = {}
user = auth_utils.get_user(request)
# Several service policy engines default to a project id check for
# ownership. Since the user is already scoped to a project, if a
# different project id has not been specified use the currently scoped
# project's id.
#
# The reason is the operator can edit the local copies of the service
# policy file. If a rule is removed, then the default rule is used. We
# don't want to block all actions because the operator did not fully
# understand the implication of editing the policy file. Additionally,
# the service APIs will correct us if we are too permissive.
if target.get('project_id') is None:
target['project_id'] = user.project_id
# same for user_id
if target.get('user_id') is None:
target['user_id'] = user.id
# same for domain_id
if target.get('domain_id') is None:
target['domain_id'] = user.domain_id
credentials = _user_to_credentials(request, user)
enforcer = _get_enforcer()
for action in actions:
scope, action = action[0], action[1]
if scope in enforcer:
# if any check fails return failure
if not enforcer[scope].enforce(action, target, credentials):
# to match service implementations, if a rule is not found,
# use the default rule for that service policy
#
# waiting to make the check because the first call to
# enforce loads the rules
if action not in enforcer[scope].rules:
if not enforcer[scope].enforce('default',
target, credentials):
return False
else:
return False
# if no policy for scope, allow action, underlying API will
# ultimately block the action if not permitted, treat as though
# allowed
return True
def _user_to_credentials(request, user):
if not hasattr(user, "_credentials"):
roles = [role['name'] for role in user.roles]
user._credentials = {'user_id': user.id,
'token': user.token,
'username': user.username,
'project_id': user.project_id,
'project_name': user.project_name,
'domain_id': user.user_domain_id,
'is_admin': user.is_superuser,
'roles': roles}
return user._credentials