# 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.
"""Token provider interface."""
import base64
import datetime
import uuid
from oslo_log import log
from oslo_utils import timeutils
from keystone.common import cache
from keystone.common import manager
from keystone.common import provider_api
from keystone.common import utils
import keystone.conf
from keystone import exception
from keystone.federation import constants
from keystone.i18n import _
from keystone.models import token_model
from keystone import notifications
CONF = keystone.conf.CONF
LOG = log.getLogger(__name__)
PROVIDERS = provider_api.ProviderAPIs
TOKENS_REGION = cache.create_region(name='tokens')
MEMOIZE_TOKENS = cache.get_memoization_decorator(
group='token',
region=TOKENS_REGION)
# NOTE(morganfainberg): This is for compatibility in case someone was relying
# on the old location of the UnsupportedTokenVersionException for their code.
UnsupportedTokenVersionException = exception.UnsupportedTokenVersionException
# supported token versions
V3 = token_model.V3
VERSIONS = token_model.VERSIONS
# minimum access rules support
ACCESS_RULES_MIN_VERSION = token_model.ACCESS_RULES_MIN_VERSION
[docs]
def default_expire_time():
"""Determine when a fresh token should expire.
Expiration time varies based on configuration (see ``[token] expiration``).
:returns: a naive UTC datetime.datetime object
"""
expire_delta = datetime.timedelta(seconds=CONF.token.expiration)
expires_at = timeutils.utcnow() + expire_delta
return expires_at.replace(microsecond=0)
[docs]
def random_urlsafe_str():
"""Generate a random URL-safe string.
:rtype: str
"""
# chop the padding (==) off the end of the encoding to save space
return base64.urlsafe_b64encode(uuid.uuid4().bytes)[:-2].decode('utf-8')
[docs]
class Manager(manager.Manager):
"""Default pivot point for the token provider backend.
See :mod:`keystone.common.manager.Manager` for more details on how this
dynamically calls the backend.
"""
driver_namespace = 'keystone.token.provider'
_provides_api = 'token_provider_api'
V3 = V3
VERSIONS = VERSIONS
def __init__(self):
super(Manager, self).__init__(CONF.token.provider)
self._register_callback_listeners()
def _register_callback_listeners(self):
# This is used by the @dependency.provider decorator to register the
# provider (token_provider_api) manager to listen for trust deletions.
callbacks = {
notifications.ACTIONS.deleted: [
['OS-TRUST:trust', self._drop_token_cache],
['user', self._drop_token_cache],
['domain', self._drop_token_cache],
],
notifications.ACTIONS.disabled: [
['user', self._drop_token_cache],
['domain', self._drop_token_cache],
['project', self._drop_token_cache],
],
notifications.ACTIONS.internal: [
[notifications.INVALIDATE_TOKEN_CACHE,
self._drop_token_cache],
]
}
for event, cb_info in callbacks.items():
for resource_type, callback_fns in cb_info:
notifications.register_event_callback(event, resource_type,
callback_fns)
def _drop_token_cache(self, service, resource_type, operation, payload):
"""Invalidate the entire token cache.
This is a handy private utility method that should be used when
consuming notifications that signal invalidating the token cache.
"""
if CONF.token.cache_on_issue or CONF.token.caching:
TOKENS_REGION.invalidate()
[docs]
@MEMOIZE_TOKENS
def check_revocation_v3(self, token_values):
PROVIDERS.revoke_api.check_token(token_values)
[docs]
def check_revocation(self, token):
token_values = self.revoke_api.model.build_token_values(token)
return self.check_revocation_v3(token_values)
[docs]
def validate_token(self, token_id, window_seconds=0,
access_rules_support=None):
if not token_id:
raise exception.TokenNotFound(_('No token in the request'))
try:
token = self._validate_token(token_id)
self._is_valid_token(token, window_seconds=window_seconds)
self._validate_token_access_rules(token, access_rules_support)
return token
except exception.Unauthorized as e:
LOG.debug('Unable to validate token: %s', e)
raise exception.TokenNotFound(token_id=token_id)
@MEMOIZE_TOKENS
def _validate_token(self, token_id):
(user_id, methods, audit_ids, system, domain_id,
project_id, trust_id, federated_group_ids, identity_provider_id,
protocol_id, access_token_id, app_cred_id, thumbprint,
issued_at, expires_at) = self.driver.validate_token(token_id)
token = token_model.TokenModel()
token.user_id = user_id
token.methods = methods
if len(audit_ids) > 1:
token.parent_audit_id = audit_ids.pop()
token.audit_id = audit_ids.pop()
token.system = system
token.domain_id = domain_id
token.project_id = project_id
token.trust_id = trust_id
token.access_token_id = access_token_id
token.application_credential_id = app_cred_id
token.oauth2_thumbprint = thumbprint
token.expires_at = expires_at
if federated_group_ids is not None:
token.is_federated = True
token.identity_provider_id = identity_provider_id
token.protocol_id = protocol_id
token.federated_groups = federated_group_ids
token.mint(token_id, issued_at)
return token
def _is_valid_token(self, token, window_seconds=0):
"""Verify the token is valid format and has not expired."""
current_time = timeutils.normalize_time(timeutils.utcnow())
try:
expiry = timeutils.parse_isotime(token.expires_at)
expiry = timeutils.normalize_time(expiry)
# add a window in which you can fetch a token beyond expiry
expiry += datetime.timedelta(seconds=window_seconds)
except Exception:
LOG.exception('Unexpected error or malformed token '
'determining token expiry: %s', token)
raise exception.TokenNotFound(_('Failed to validate token'))
if current_time < expiry:
self.check_revocation(token)
# Token has not expired and has not been revoked.
return None
else:
raise exception.TokenNotFound(_('Failed to validate token'))
def _validate_token_access_rules(self, token, access_rules_support=None):
if token.application_credential_id:
app_cred_api = PROVIDERS.application_credential_api
app_cred = app_cred_api.get_application_credential(
token.application_credential_id)
if (app_cred.get('access_rules') is not None and
(not access_rules_support or
(float(access_rules_support) < ACCESS_RULES_MIN_VERSION))):
LOG.exception('Attempted to use application credential'
' access rules with a middleware that does not'
' understand them. You must upgrade'
' keystonemiddleware on all services that'
' accept application credentials as an'
' authentication method.')
raise exception.TokenNotFound(_('Failed to validate token'))
[docs]
def issue_token(self, user_id, method_names, expires_at=None,
system=None, project_id=None, domain_id=None,
auth_context=None, trust_id=None, app_cred_id=None,
thumbprint=None, parent_audit_id=None):
# NOTE(lbragstad): Grab a blank token object and use composition to
# build the token according to the authentication and authorization
# context. This cuts down on the amount of logic we have to stuff into
# the TokenModel's __init__() method.
token = token_model.TokenModel()
token.methods = method_names
token.system = system
token.domain_id = domain_id
token.project_id = project_id
token.trust_id = trust_id
token.application_credential_id = app_cred_id
token.audit_id = random_urlsafe_str()
token.oauth2_thumbprint = thumbprint
token.parent_audit_id = parent_audit_id
if auth_context:
if constants.IDENTITY_PROVIDER in auth_context:
token.is_federated = True
token.protocol_id = auth_context[constants.PROTOCOL]
idp_id = auth_context[constants.IDENTITY_PROVIDER]
if isinstance(idp_id, bytes):
idp_id = idp_id.decode('utf-8')
token.identity_provider_id = idp_id
token.user_id = auth_context['user_id']
token.federated_groups = [
{'id': group} for group in auth_context['group_ids']
]
if 'access_token_id' in auth_context:
token.access_token_id = auth_context['access_token_id']
if not token.user_id:
token.user_id = user_id
token.user_domain_id = token.user['domain_id']
if isinstance(expires_at, datetime.datetime):
token.expires_at = utils.isotime(expires_at, subsecond=True)
if isinstance(expires_at, str):
token.expires_at = expires_at
elif not expires_at:
token.expires_at = utils.isotime(
default_expire_time(), subsecond=True
)
# NOTE(d34dh0r53): If this token is being issued with an application
# credential and the application credential expires before the token
# we need to set the token expiration to be the same as the application
# credential. See CVE-2022-2447 for more information.
if app_cred_id is not None:
app_cred_api = PROVIDERS.application_credential_api
app_cred = app_cred_api.get_application_credential(
token.application_credential_id)
token_time = timeutils.normalize_time(
timeutils.parse_isotime(token.expires_at))
if (app_cred['expires_at'] is not None) and (
token_time > app_cred['expires_at']):
token.expires_at = app_cred['expires_at'].isoformat()
LOG.debug('Resetting token expiration to the application'
' credential expiration: %s',
app_cred['expires_at'].isoformat())
token_id, issued_at = self.driver.generate_id_and_issued_at(token)
token.mint(token_id, issued_at)
# cache the token object and with ID
if CONF.token.cache_on_issue or CONF.token.caching:
# NOTE(amakarov): here and above TOKENS_REGION is to be passed
# to serve as required positional "self" argument. It's ignored,
# so I've put it here for convenience - any placeholder is fine.
self._validate_token.set(token, self, token.id)
return token
[docs]
def invalidate_individual_token_cache(self, token):
# NOTE(morganfainberg): invalidate takes the exact same arguments as
# the normal method, this means we need to pass "self" in (which gets
# stripped off).
# FIXME(morganfainberg): Does this cache actually need to be
# invalidated? We maintain a cached revocation list, which should be
# consulted before accepting a token as valid. For now we will
# do the explicit individual token invalidation.
self._validate_token.invalidate(self, token.id)
token_values = self.revoke_api.model.build_token_values(token)
self.check_revocation_v3.invalidate(self, token_values)
[docs]
def revoke_token(self, token_id, revoke_chain=False):
token = self.validate_token(token_id)
project_id = token.project_id if token.project_scoped else None
domain_id = token.domain_id if token.domain_scoped else None
if revoke_chain:
PROVIDERS.revoke_api.revoke_by_audit_chain_id(
token.parent_audit_id, project_id=project_id,
domain_id=domain_id
)
else:
PROVIDERS.revoke_api.revoke_by_audit_id(token.audit_id)
# FIXME(morganfainberg): Does this cache actually need to be
# invalidated? We maintain a cached revocation list, which should be
# consulted before accepting a token as valid. For now we will
# do the explicit individual token invalidation.
self.invalidate_individual_token_cache(token)
