# Copyright 2012 OpenStack Foundation
#
# 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.
"""Main entry point into the Trust service."""
import abc
from oslo_config import cfg
import six
from six.moves import zip
from keystone.common import dependency
from keystone.common import manager
from keystone import exception
from keystone.i18n import _
from keystone import notifications
CONF = cfg.CONF
@dependency.requires('identity_api')
@dependency.provider('trust_api')
class Manager(manager.Manager):
"""Default pivot point for the Trust backend.
See :mod:`keystone.common.manager.Manager` for more details on how this
dynamically calls the backend.
"""
driver_namespace = 'keystone.trust'
_TRUST = "OS-TRUST:trust"
def __init__(self):
super(Manager, self).__init__(CONF.trust.driver)
@staticmethod
def _validate_redelegation(redelegated_trust, trust):
# Validate against:
# 0 < redelegation_count <= max_redelegation_count
max_redelegation_count = CONF.trust.max_redelegation_count
redelegation_depth = redelegated_trust.get('redelegation_count', 0)
if not (0 < redelegation_depth <= max_redelegation_count):
raise exception.Forbidden(
_('Remaining redelegation depth of %(redelegation_depth)d'
' out of allowed range of [0..%(max_count)d]') %
{'redelegation_depth': redelegation_depth,
'max_count': max_redelegation_count})
# remaining_uses is None
remaining_uses = trust.get('remaining_uses')
if remaining_uses is not None:
raise exception.Forbidden(
_('Field "remaining_uses" is set to %(value)s'
' while it must not be set in order to redelegate a trust'),
value=remaining_uses)
# expiry times
trust_expiry = trust.get('expires_at')
redelegated_expiry = redelegated_trust['expires_at']
if trust_expiry:
# redelegated trust is from backend and has no tzinfo
if redelegated_expiry < trust_expiry.replace(tzinfo=None):
raise exception.Forbidden(
_('Requested expiration time is more '
'than redelegated trust can provide'))
else:
trust['expires_at'] = redelegated_expiry
# trust roles is a subset of roles of the redelegated trust
parent_roles = set(role['id']
for role in redelegated_trust['roles'])
if not all(role['id'] in parent_roles for role in trust['roles']):
raise exception.Forbidden(
_('Some of requested roles are not in redelegated trust'))
def get_trust_pedigree(self, trust_id):
trust = self.driver.get_trust(trust_id)
trust_chain = [trust]
while trust and trust.get('redelegated_trust_id'):
trust = self.driver.get_trust(trust['redelegated_trust_id'])
trust_chain.append(trust)
return trust_chain
def get_trust(self, trust_id, deleted=False):
trust = self.driver.get_trust(trust_id, deleted)
if trust and trust.get('redelegated_trust_id') and not deleted:
trust_chain = self.get_trust_pedigree(trust_id)
for parent, child in zip(trust_chain[1:], trust_chain):
self._validate_redelegation(parent, child)
try:
self.identity_api.assert_user_enabled(
parent['trustee_user_id'])
except (AssertionError, exception.NotFound):
raise exception.Forbidden(
_('One of the trust agents is disabled or deleted'))
return trust
def create_trust(self, trust_id, trust, roles, redelegated_trust=None,
initiator=None):
"""Create a new trust.
:returns: a new trust
"""
# Default for initial trust in chain is max_redelegation_count
max_redelegation_count = CONF.trust.max_redelegation_count
requested_count = trust.get('redelegation_count')
redelegatable = (trust.pop('allow_redelegation', False)
and requested_count != 0)
if not redelegatable:
trust['redelegation_count'] = requested_count = 0
remaining_uses = trust.get('remaining_uses')
if remaining_uses is not None and remaining_uses <= 0:
msg = _('remaining_uses must be a positive integer or null.')
raise exception.ValidationError(msg)
else:
# Validate requested redelegation depth
if requested_count and requested_count > max_redelegation_count:
raise exception.Forbidden(
_('Requested redelegation depth of %(requested_count)d '
'is greater than allowed %(max_count)d') %
{'requested_count': requested_count,
'max_count': max_redelegation_count})
# Decline remaining_uses
if trust.get('remaining_uses') is not None:
raise exception.ValidationError(
_('remaining_uses must not be set if redelegation is '
'allowed'))
if redelegated_trust:
trust['redelegated_trust_id'] = redelegated_trust['id']
remaining_count = redelegated_trust['redelegation_count'] - 1
# Validate depth consistency
if (redelegatable and requested_count and
requested_count != remaining_count):
msg = _('Modifying "redelegation_count" upon redelegation is '
'forbidden. Omitting this parameter is advised.')
raise exception.Forbidden(msg)
trust.setdefault('redelegation_count', remaining_count)
# Check entire trust pedigree validity
pedigree = self.get_trust_pedigree(redelegated_trust['id'])
for t in pedigree:
self._validate_redelegation(t, trust)
trust.setdefault('redelegation_count', max_redelegation_count)
ref = self.driver.create_trust(trust_id, trust, roles)
notifications.Audit.created(self._TRUST, trust_id, initiator=initiator)
return ref
def delete_trust(self, trust_id, initiator=None):
"""Remove a trust.
:raises keystone.exception.TrustNotFound: If the trust doesn't exist.
Recursively remove given and redelegated trusts
"""
trust = self.driver.get_trust(trust_id)
trusts = self.driver.list_trusts_for_trustor(
trust['trustor_user_id'])
for t in trusts:
if t.get('redelegated_trust_id') == trust_id:
# recursive call to make sure all notifications are sent
try:
self.delete_trust(t['id'])
except exception.TrustNotFound: # nosec
# if trust was deleted by concurrent process
# consistency must not suffer
pass
# end recursion
self.driver.delete_trust(trust_id)
notifications.Audit.deleted(self._TRUST, trust_id, initiator)
@six.add_metaclass(abc.ABCMeta)
class TrustDriverV8(object):
@abc.abstractmethod
def create_trust(self, trust_id, trust, roles):
"""Create a new trust.
:returns: a new trust
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def get_trust(self, trust_id, deleted=False):
"""Get a trust by the trust id.
:param trust_id: the trust identifier
:type trust_id: string
:param deleted: return the trust even if it is deleted, expired, or
has no consumptions left
:type deleted: bool
"""
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def list_trusts(self):
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def list_trusts_for_trustee(self, trustee):
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def list_trusts_for_trustor(self, trustor):
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def delete_trust(self, trust_id):
raise exception.NotImplemented() # pragma: no cover
@abc.abstractmethod
def consume_use(self, trust_id):
"""Consume one use of a trust.
One use of a trust is consumed when the trust was created with a
limitation on its uses, provided there are still uses available.
:raises keystone.exception.TrustUseLimitReached: If no remaining uses
for trust.
:raises keystone.exception.TrustNotFound: If the trust doesn't exist.
"""
raise exception.NotImplemented() # pragma: no cover
Driver = manager.create_legacy_driver(TrustDriverV8)