135 lines
4.7 KiB
Python
135 lines
4.7 KiB
Python
# Copyright (c) 2013 The Johns Hopkins University/Applied Physics Laboratory
|
|
# 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.
|
|
|
|
"""
|
|
An implementation of a key manager that reads its key from the project's
|
|
configuration options.
|
|
|
|
This key manager implementation provides limited security, assuming that the
|
|
key remains secret. Using the volume encryption feature as an example,
|
|
encryption provides protection against a lost or stolen disk, assuming that
|
|
the configuration file that contains the key is not stored on the disk.
|
|
Encryption also protects the confidentiality of data as it is transmitted via
|
|
iSCSI from the compute host to the storage host (again assuming that an
|
|
attacker who intercepts the data does not know the secret key).
|
|
|
|
Because this implementation uses a single, fixed key, it proffers no
|
|
protection once that key is compromised. In particular, different volumes
|
|
encrypted with a key provided by this key manager actually share the same
|
|
encryption key so *any* volume can be decrypted once the fixed key is known.
|
|
"""
|
|
|
|
import array
|
|
|
|
from oslo.config import cfg
|
|
|
|
from cinder import exception
|
|
from cinder.keymgr import key
|
|
from cinder.keymgr import key_mgr
|
|
from cinder.openstack.common.gettextutils import _
|
|
from cinder.openstack.common import log as logging
|
|
|
|
|
|
key_mgr_opts = [
|
|
cfg.StrOpt('fixed_key',
|
|
help='Fixed key returned by key manager, specified in hex'),
|
|
]
|
|
|
|
CONF = cfg.CONF
|
|
CONF.register_opts(key_mgr_opts, group='keymgr')
|
|
|
|
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
|
|
class ConfKeyManager(key_mgr.KeyManager):
|
|
"""Key Manager that supports one key defined by the fixed_key conf option.
|
|
|
|
This key manager implementation supports all the methods specified by the
|
|
key manager interface. This implementation creates a single key in response
|
|
to all invocations of create_key. Side effects (e.g., raising exceptions)
|
|
for each method are handled as specified by the key manager interface.
|
|
"""
|
|
|
|
def __init__(self):
|
|
super(ConfKeyManager, self).__init__()
|
|
|
|
self.key_id = '00000000-0000-0000-0000-000000000000'
|
|
|
|
def _generate_key(self, **kwargs):
|
|
_hex = self._generate_hex_key(**kwargs)
|
|
return key.SymmetricKey('AES',
|
|
array.array('B', _hex.decode('hex')).tolist())
|
|
|
|
def _generate_hex_key(self, **kwargs):
|
|
if CONF.keymgr.fixed_key is None:
|
|
LOG.warn(_('config option keymgr.fixed_key has not been defined: '
|
|
'some operations may fail unexpectedly'))
|
|
raise ValueError(_('keymgr.fixed_key not defined'))
|
|
return CONF.keymgr.fixed_key
|
|
|
|
def create_key(self, ctxt, **kwargs):
|
|
"""Creates a key.
|
|
|
|
This implementation returns a UUID for the created key. A
|
|
NotAuthorized exception is raised if the specified context is None.
|
|
"""
|
|
if ctxt is None:
|
|
raise exception.NotAuthorized()
|
|
|
|
return self.key_id
|
|
|
|
def store_key(self, ctxt, key, **kwargs):
|
|
"""Stores (i.e., registers) a key with the key manager."""
|
|
if ctxt is None:
|
|
raise exception.NotAuthorized()
|
|
|
|
if key != self._generate_key():
|
|
raise exception.KeyManagerError(
|
|
reason="cannot store arbitrary keys")
|
|
|
|
return self.key_id
|
|
|
|
def copy_key(self, ctxt, key_id, **kwargs):
|
|
if ctxt is None:
|
|
raise exception.NotAuthorized()
|
|
|
|
return self.key_id
|
|
|
|
def get_key(self, ctxt, key_id, **kwargs):
|
|
"""Retrieves the key identified by the specified id.
|
|
|
|
This implementation returns the key that is associated with the
|
|
specified UUID. A NotAuthorized exception is raised if the specified
|
|
context is None; a KeyError is raised if the UUID is invalid.
|
|
"""
|
|
if ctxt is None:
|
|
raise exception.NotAuthorized()
|
|
|
|
if key_id != self.key_id:
|
|
raise KeyError(key_id)
|
|
|
|
return self._generate_key()
|
|
|
|
def delete_key(self, ctxt, key_id, **kwargs):
|
|
if ctxt is None:
|
|
raise exception.NotAuthorized()
|
|
|
|
if key_id != self.key_id:
|
|
raise exception.KeyManagerError(
|
|
reason="cannot delete non-existent key")
|
|
|
|
LOG.warn(_("Not deleting key %s"), key_id)
|