# 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. """ Key manager implementation for Vault """ import binascii from cryptography.hazmat.backends import default_backend from cryptography.hazmat.primitives.asymmetric import rsa from cryptography.hazmat.primitives.serialization import Encoding from cryptography.hazmat.primitives.serialization import NoEncryption from cryptography.hazmat.primitives.serialization import PrivateFormat from cryptography.hazmat.primitives.serialization import PublicFormat import os import time import uuid from keystoneauth1 import loading from oslo_config import cfg from oslo_log import log as logging from oslo_utils import timeutils import requests import six from castellan.common import exception from castellan.common.objects import opaque_data as op_data from castellan.common.objects import passphrase from castellan.common.objects import private_key as pri_key from castellan.common.objects import public_key as pub_key from castellan.common.objects import symmetric_key as sym_key from castellan.common.objects import x_509 from castellan.i18n import _ from castellan.key_manager import key_manager DEFAULT_VAULT_URL = "http://127.0.0.1:8200" DEFAULT_MOUNTPOINT = "secret" vault_opts = [ cfg.StrOpt('root_token_id', help='root token for vault'), cfg.StrOpt('approle_role_id', help='AppRole role_id for authentication with vault'), cfg.StrOpt('approle_secret_id', help='AppRole secret_id for authentication with vault'), cfg.StrOpt('kv_mountpoint', default=DEFAULT_MOUNTPOINT, help='Mountpoint of KV store in Vault to use, for example: ' '{}'.format(DEFAULT_MOUNTPOINT)), cfg.StrOpt('vault_url', default=DEFAULT_VAULT_URL, help='Use this endpoint to connect to Vault, for example: ' '"%s"' % DEFAULT_VAULT_URL), cfg.StrOpt('ssl_ca_crt_file', help='Absolute path to ca cert file'), cfg.BoolOpt('use_ssl', default=False, help=_('SSL Enabled/Disabled')), ] VAULT_OPT_GROUP = 'vault' _EXCEPTIONS_BY_CODE = [ requests.codes['internal_server_error'], requests.codes['service_unavailable'], requests.codes['request_timeout'], requests.codes['gateway_timeout'], requests.codes['precondition_failed'], ] LOG = logging.getLogger(__name__) class VaultKeyManager(key_manager.KeyManager): """Key Manager Interface that wraps the Vault REST API.""" _secret_type_dict = { op_data.OpaqueData: 'opaque', passphrase.Passphrase: 'passphrase', pri_key.PrivateKey: 'private', pub_key.PublicKey: 'public', sym_key.SymmetricKey: 'symmetric', x_509.X509: 'certificate'} def __init__(self, configuration): self._conf = configuration self._conf.register_opts(vault_opts, group=VAULT_OPT_GROUP) loading.register_session_conf_options(self._conf, VAULT_OPT_GROUP) self._session = requests.Session() self._root_token_id = self._conf.vault.root_token_id self._approle_role_id = self._conf.vault.approle_role_id self._approle_secret_id = self._conf.vault.approle_secret_id self._cached_approle_token_id = None self._approle_token_ttl = None self._approle_token_issue = None self._kv_mountpoint = self._conf.vault.kv_mountpoint self._vault_url = self._conf.vault.vault_url if self._vault_url.startswith("https://"): self._verify_server = self._conf.vault.ssl_ca_crt_file or True else: self._verify_server = False self._vault_kv_version = None def _get_url(self): if not self._vault_url.endswith('/'): self._vault_url += '/' return self._vault_url def _get_api_version(self): if self._vault_kv_version: return self._vault_kv_version resource_url = '{}v1/sys/internal/ui/mounts/{}'.format( self._get_url(), self._kv_mountpoint ) resp = self._do_http_request(self._session.get, resource_url) if resp.status_code == requests.codes['not_found']: self._vault_kv_version = '1' else: self._vault_kv_version = resp.json()['data']['options']['version'] return self._vault_kv_version def _get_resource_url(self, key_id=None): return '{}v1/{}/{}{}'.format( self._get_url(), self._kv_mountpoint, '' if self._get_api_version() == '1' else 'data/' if key_id else 'metadata/', # no key_id is for listing and 'data/' doesn't works key_id if key_id else '?list=true') @property def _approle_token_id(self): if (all((self._approle_token_issue, self._approle_token_ttl)) and timeutils.is_older_than(self._approle_token_issue, self._approle_token_ttl)): self._cached_approle_token_id = None return self._cached_approle_token_id def _build_auth_headers(self): if self._root_token_id: return {'X-Vault-Token': self._root_token_id} if self._approle_token_id: return {'X-Vault-Token': self._approle_token_id} if self._approle_role_id: params = { 'role_id': self._approle_role_id } if self._approle_secret_id: params['secret_id'] = self._approle_secret_id approle_login_url = '{}v1/auth/approle/login'.format( self._get_url() ) token_issue_utc = timeutils.utcnow() try: resp = self._session.post(url=approle_login_url, json=params, verify=self._verify_server) except requests.exceptions.Timeout as ex: raise exception.KeyManagerError(six.text_type(ex)) except requests.exceptions.ConnectionError as ex: raise exception.KeyManagerError(six.text_type(ex)) except Exception as ex: raise exception.KeyManagerError(six.text_type(ex)) if resp.status_code in _EXCEPTIONS_BY_CODE: raise exception.KeyManagerError(resp.reason) if resp.status_code == requests.codes['forbidden']: raise exception.Forbidden() resp = resp.json() self._cached_approle_token_id = resp['auth']['client_token'] self._approle_token_issue = token_issue_utc self._approle_token_ttl = resp['auth']['lease_duration'] return {'X-Vault-Token': self._approle_token_id} return {} def _do_http_request(self, method, resource, json=None): verify = self._verify_server headers = self._build_auth_headers() try: resp = method(resource, headers=headers, json=json, verify=verify) except requests.exceptions.Timeout as ex: raise exception.KeyManagerError(six.text_type(ex)) except requests.exceptions.ConnectionError as ex: raise exception.KeyManagerError(six.text_type(ex)) except Exception as ex: raise exception.KeyManagerError(six.text_type(ex)) if resp.status_code in _EXCEPTIONS_BY_CODE: raise exception.KeyManagerError(resp.reason) if resp.status_code == requests.codes['forbidden']: raise exception.Forbidden() return resp def create_key_pair(self, context, algorithm, length, expiration=None, name=None): """Creates an asymmetric key pair.""" # Confirm context is provided, if not raise forbidden if not context: msg = _("User is not authorized to use key manager.") raise exception.Forbidden(msg) if algorithm.lower() != 'rsa': raise NotImplementedError( "VaultKeyManager only implements rsa keys" ) priv_key = rsa.generate_private_key( public_exponent=65537, key_size=length, backend=default_backend() ) private_key = pri_key.PrivateKey( 'RSA', length, priv_key.private_bytes( Encoding.PEM, PrivateFormat.PKCS8, NoEncryption() ) ) private_key_id = uuid.uuid4().hex private_id = self._store_key_value( private_key_id, private_key ) # pub_key = priv_key.public_key() public_key = pub_key.PublicKey( 'RSA', length, priv_key.public_key().public_bytes( Encoding.PEM, PublicFormat.SubjectPublicKeyInfo ) ) public_key_id = uuid.uuid4().hex public_id = self._store_key_value( public_key_id, public_key ) return private_id, public_id def _store_key_value(self, key_id, value): type_value = self._secret_type_dict.get(type(value)) if type_value is None: raise exception.KeyManagerError( "Unknown type for value : %r" % value) record = { 'type': type_value, 'value': binascii.hexlify(value.get_encoded()).decode('utf-8'), 'algorithm': (value.algorithm if hasattr(value, 'algorithm') else None), 'bit_length': (value.bit_length if hasattr(value, 'bit_length') else None), 'name': value.name, 'created': value.created } if self._get_api_version() != '1': record = {'data': record} self._do_http_request(self._session.post, self._get_resource_url(key_id), json=record) return key_id def create_key(self, context, algorithm, length, name=None, **kwargs): """Creates a symmetric key.""" # Confirm context is provided, if not raise forbidden if not context: msg = _("User is not authorized to use key manager.") raise exception.Forbidden(msg) key_id = uuid.uuid4().hex key_value = os.urandom(length or 32) key = sym_key.SymmetricKey(algorithm, length or 32, key_value, key_id, name or int(time.time())) return self._store_key_value(key_id, key) def store(self, context, key_value, **kwargs): """Stores (i.e., registers) a key with the key manager.""" # Confirm context is provided, if not raise forbidden if not context: msg = _("User is not authorized to use key manager.") raise exception.Forbidden(msg) key_id = uuid.uuid4().hex return self._store_key_value(key_id, key_value) def get(self, context, key_id, metadata_only=False): """Retrieves the key identified by the specified id.""" # Confirm context is provided, if not raise forbidden if not context: msg = _("User is not authorized to use key manager.") raise exception.Forbidden(msg) if not key_id: raise exception.KeyManagerError('key identifier not provided') resp = self._do_http_request(self._session.get, self._get_resource_url(key_id)) if resp.status_code == requests.codes['not_found']: raise exception.ManagedObjectNotFoundError(uuid=key_id) record = resp.json()['data'] if self._get_api_version() != '1': record = record['data'] key = None if metadata_only else binascii.unhexlify(record['value']) clazz = None for type_clazz, type_name in self._secret_type_dict.items(): if type_name == record['type']: clazz = type_clazz if clazz is None: raise exception.KeyManagerError( "Unknown type : %r" % record['type']) if hasattr(clazz, 'algorithm') and hasattr(clazz, 'bit_length'): return clazz(record['algorithm'], record['bit_length'], key, record['name'], record['created'], key_id) else: return clazz(key, record['name'], record['created'], key_id) def delete(self, context, key_id): """Represents deleting the key.""" # Confirm context is provided, if not raise forbidden if not context: msg = _("User is not authorized to use key manager.") raise exception.Forbidden(msg) if not key_id: raise exception.KeyManagerError('key identifier not provided') resp = self._do_http_request(self._session.delete, self._get_resource_url(key_id)) if resp.status_code == requests.codes['not_found']: raise exception.ManagedObjectNotFoundError(uuid=key_id) def list(self, context, object_type=None, metadata_only=False): """Lists the managed objects given the criteria.""" # Confirm context is provided, if not raise forbidden if not context: msg = _("User is not authorized to use key manager.") raise exception.Forbidden(msg) if object_type and object_type not in self._secret_type_dict: msg = _("Invalid secret type: %s") % object_type raise exception.KeyManagerError(reason=msg) resp = self._do_http_request(self._session.get, self._get_resource_url()) if resp.status_code == requests.codes['not_found']: keys = [] else: keys = resp.json()['data']['keys'] objects = [] for obj_id in keys: try: obj = self.get(context, obj_id, metadata_only=metadata_only) if object_type is None or isinstance(obj, object_type): objects.append(obj) except exception.ManagedObjectNotFoundError as e: LOG.warning(_("Error occurred while retrieving object " "metadata, not adding it to the list: %s"), e) pass return objects