deb-barbican/barbican/plugin/kmip_secret_store.py

612 lines
25 KiB
Python

# Copyright (c) 2014 Johns Hopkins University Applied Physics Laboratory
#
# 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 the SecretStore that uses the KMIP backend.
"""
import base64
import os
import ssl
import stat
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import serialization
from kmip.core import enums
from kmip.core.factories import credentials
from kmip.pie import client
from kmip.pie import objects
from oslo_config import cfg
from oslo_log import log
from barbican.common import config
from barbican.common import exception
from barbican import i18n as u # noqa
from barbican.plugin.interface import secret_store as ss
from barbican.plugin.util import translations
LOG = log.getLogger(__name__)
CONF = config.new_config()
kmip_opt_group = cfg.OptGroup(name='kmip_plugin', title='KMIP Plugin')
kmip_opts = [
cfg.StrOpt('username',
help=u._('Username for authenticating with KMIP server')
),
cfg.StrOpt('password',
help=u._('Password for authenticating with KMIP server'),
secret=True,
),
cfg.StrOpt('host',
default='localhost',
help=u._('Address of the KMIP server')
),
cfg.StrOpt('port',
default='5696',
help=u._('Port for the KMIP server'),
),
cfg.StrOpt('ssl_version',
default='PROTOCOL_TLSv1',
help=u._('SSL version, maps to the module ssl\'s constants'),
),
cfg.StrOpt('ca_certs',
help=u._('File path to concatenated "certification authority" '
'certificates'),
),
cfg.StrOpt('certfile',
help=u._('File path to local client certificate'),
),
cfg.StrOpt('keyfile',
help=u._('File path to local client certificate keyfile'),
),
cfg.BoolOpt('pkcs1_only',
default=False,
help=u._('Only support PKCS#1 encoding of asymmetric keys'),
),
cfg.StrOpt('plugin_name',
help=u._('User friendly plugin name'),
default='KMIP HSM'),
]
CONF.register_group(kmip_opt_group)
CONF.register_opts(kmip_opts, group=kmip_opt_group)
config.parse_args(CONF)
attribute_debug_msg = "Created attribute type %s with value %s"
def convert_pem_to_der(pem_pkcs1):
# cryptography adds an extra '\n' to end of PEM file
# added if statement so if future version removes extra \n tests will not
# break
if pem_pkcs1.endswith(b'\n'):
pem_pkcs1 = pem_pkcs1[:-1]
# neither PyCrypto or cryptography support export in DER format with PKCS1
# encoding so doing by hand
der_pkcs1_b64 = b''.join(pem_pkcs1.split(b'\n')[1:-1])
der_pkcs1 = base64.b64decode(der_pkcs1_b64)
return der_pkcs1
def get_public_key_der_pkcs1(pem):
"""Converts PEM public key to DER PKCS1"""
rsa_public = serialization.load_pem_public_key(
pem,
backend=default_backend())
pem_pkcs1 = rsa_public.public_bytes(
encoding=serialization.Encoding.PEM,
format=serialization.PublicFormat.PKCS1)
return convert_pem_to_der(pem_pkcs1)
def get_private_key_der_pkcs1(pem):
"""Converts PEM private key to DER PKCS1"""
rsa_private = serialization.load_pem_private_key(
pem,
None,
backend=default_backend())
pem_pkcs1 = rsa_private.private_bytes(
encoding=serialization.Encoding.PEM,
format=serialization.PrivateFormat.TraditionalOpenSSL,
encryption_algorithm=serialization.NoEncryption())
return convert_pem_to_der(pem_pkcs1)
class KMIPSecretStoreError(exception.BarbicanException):
def __init__(self, message):
super(KMIPSecretStoreError, self).__init__(message)
class KMIPSecretStoreActionNotSupported(exception.BarbicanHTTPException):
"""Raised if no plugins are found that support the requested operation."""
client_message = u._("KMIP plugin action not support.")
status_code = 400
def __init__(self, message):
self.message = message
super(KMIPSecretStoreActionNotSupported, self).__init__()
class KMIPSecretStore(ss.SecretStoreBase):
KEY_UUID = "key_uuid"
VALID_BIT_LENGTHS = "valid_bit_lengths"
KMIP_ALGORITHM_ENUM = "kmip_algorithm_enum"
def __init__(self, conf=CONF):
"""Initializes KMIPSecretStore
Creates a dictionary of mappings between SecretStore enum values
and pyKMIP enum values. Initializes the KMIP client with credentials
needed to connect to the KMIP server.
"""
super(KMIPSecretStore, self).__init__()
self.valid_alg_dict = {
ss.KeyAlgorithm.AES: {
KMIPSecretStore.VALID_BIT_LENGTHS: [128, 192, 256],
KMIPSecretStore.KMIP_ALGORITHM_ENUM:
enums.CryptographicAlgorithm.AES},
ss.KeyAlgorithm.DES: {
KMIPSecretStore.VALID_BIT_LENGTHS: [56],
KMIPSecretStore.KMIP_ALGORITHM_ENUM:
enums.CryptographicAlgorithm.DES},
ss.KeyAlgorithm.DESEDE: {
KMIPSecretStore.VALID_BIT_LENGTHS:
[56, 64, 112, 128, 168, 192],
KMIPSecretStore.KMIP_ALGORITHM_ENUM:
enums.CryptographicAlgorithm.TRIPLE_DES},
ss.KeyAlgorithm.DSA: {
KMIPSecretStore.VALID_BIT_LENGTHS:
[1024, 2048, 3072],
KMIPSecretStore.KMIP_ALGORITHM_ENUM:
enums.CryptographicAlgorithm.DSA},
ss.KeyAlgorithm.HMACSHA1: {
KMIPSecretStore.VALID_BIT_LENGTHS:
[],
KMIPSecretStore.KMIP_ALGORITHM_ENUM:
enums.CryptographicAlgorithm.HMAC_SHA1},
ss.KeyAlgorithm.HMACSHA256: {
KMIPSecretStore.VALID_BIT_LENGTHS:
[],
KMIPSecretStore.KMIP_ALGORITHM_ENUM:
enums.CryptographicAlgorithm.HMAC_SHA256},
ss.KeyAlgorithm.HMACSHA384: {
KMIPSecretStore.VALID_BIT_LENGTHS:
[],
KMIPSecretStore.KMIP_ALGORITHM_ENUM:
enums.CryptographicAlgorithm.HMAC_SHA384},
ss.KeyAlgorithm.HMACSHA512: {
KMIPSecretStore.VALID_BIT_LENGTHS:
[],
KMIPSecretStore.KMIP_ALGORITHM_ENUM:
enums.CryptographicAlgorithm.HMAC_SHA512},
ss.KeyAlgorithm.RSA: {
KMIPSecretStore.VALID_BIT_LENGTHS:
[1024, 2048, 3072, 4096],
KMIPSecretStore.KMIP_ALGORITHM_ENUM:
enums.CryptographicAlgorithm.RSA},
}
self.pkcs1_only = conf.kmip_plugin.pkcs1_only
if self.pkcs1_only:
LOG.debug("KMIP secret store only supports PKCS#1")
del self.valid_alg_dict[ss.KeyAlgorithm.DSA]
self.kmip_barbican_alg_map = {
enums.CryptographicAlgorithm.AES: ss.KeyAlgorithm.AES,
enums.CryptographicAlgorithm.DES: ss.KeyAlgorithm.DES,
enums.CryptographicAlgorithm.TRIPLE_DES: ss.KeyAlgorithm.DESEDE,
enums.CryptographicAlgorithm.DSA: ss.KeyAlgorithm.DSA,
enums.CryptographicAlgorithm.HMAC_SHA1: ss.KeyAlgorithm.HMACSHA1,
enums.CryptographicAlgorithm.HMAC_SHA256:
ss.KeyAlgorithm.HMACSHA256,
enums.CryptographicAlgorithm.HMAC_SHA384:
ss.KeyAlgorithm.HMACSHA384,
enums.CryptographicAlgorithm.HMAC_SHA512:
ss.KeyAlgorithm.HMACSHA512,
enums.CryptographicAlgorithm.RSA: ss.KeyAlgorithm.RSA
}
self.plugin_name = conf.kmip_plugin.plugin_name
if conf.kmip_plugin.keyfile is not None:
self._validate_keyfile_permissions(conf.kmip_plugin.keyfile)
if (conf.kmip_plugin.username is None) and (
conf.kmip_plugin.password is None):
self.credential = None
else:
credential_type = credentials.CredentialType.USERNAME_AND_PASSWORD
credential_value = {'Username': conf.kmip_plugin.username,
'Password': conf.kmip_plugin.password}
self.credential = (
credentials.CredentialFactory().create_credential(
credential_type,
credential_value))
config = conf.kmip_plugin
# Use TLSv1_2, if present
tlsv12 = getattr(ssl, "PROTOCOL_TLSv1_2", None)
if tlsv12:
config.ssl_version = 'PROTOCOL_TLSv1_2'
LOG.info(u._LI('Going to use TLS1.2...'))
else:
LOG.warning(u._LW('TLSv1_2 is not present on the System'))
self.client = client.ProxyKmipClient(
hostname=config.host,
port=config.port,
cert=config.certfile,
key=config.keyfile,
ca=config.ca_certs,
ssl_version=config.ssl_version,
username=config.username,
password=config.password)
def get_plugin_name(self):
return self.plugin_name
def generate_symmetric_key(self, key_spec):
"""Generate a symmetric key.
Creates KMIP attribute objects based on the given KeySpec to send to
the server.
:param key_spec: KeySpec with symmetric algorithm and bit_length
:returns: dictionary holding key_id returned by server
:raises: SecretGeneralException, SecretAlgorithmNotSupportedException
"""
LOG.debug("Starting symmetric key generation with KMIP plugin")
if not self.generate_supports(key_spec):
raise ss.SecretAlgorithmNotSupportedException(
key_spec.alg)
if key_spec.alg.lower() not in ss.KeyAlgorithm.SYMMETRIC_ALGORITHMS:
raise KMIPSecretStoreError(
u._("An unsupported algorithm {algorithm} was passed to the "
"'generate_symmetric_key' method").format(
algorithm=key_spec.alg))
algorithm = self._get_kmip_algorithm(key_spec.alg.lower())
try:
with self.client:
LOG.debug("Opened connection to KMIP client for secret "
"generation")
uuid = self.client.create(algorithm, key_spec.bit_length)
LOG.debug("SUCCESS: Symmetric key generated with "
"uuid: %s", uuid)
return {KMIPSecretStore.KEY_UUID: uuid}
except Exception as e:
LOG.exception(u._LE("Error opening or writing to client"))
raise ss.SecretGeneralException(e)
def generate_asymmetric_key(self, key_spec):
"""Generate an asymmetric key pair.
Creates KMIP attribute objects based on the given KeySpec to send to
the server. The KMIP Secret Store currently does not support
protecting the private key with a passphrase.
:param key_spec: KeySpec with asymmetric algorithm and bit_length
:returns: AsymmetricKeyMetadataDTO with the key UUIDs
:raises: SecretGeneralException, SecretAlgorithmNotSupportedException
KMIPSecretStoreActionNotSupported
"""
LOG.debug("Starting asymmetric key generation with KMIP plugin")
if not self.generate_supports(key_spec):
raise ss.SecretAlgorithmNotSupportedException(
key_spec.alg)
if key_spec.alg.lower() not in ss.KeyAlgorithm.ASYMMETRIC_ALGORITHMS:
raise ss.SecretAlgorithmNotSupportedException(key_spec.alg)
if key_spec.passphrase:
raise KMIPSecretStoreActionNotSupported(
u._('KMIP plugin does not currently support protecting the '
'private key with a passphrase'))
algorithm = self._get_kmip_algorithm(key_spec.alg.lower())
length = key_spec.bit_length
try:
with self.client:
LOG.debug("Opened connection to KMIP client for "
"asymmetric secret generation")
public_uuid, private_uuid = self.client.create_key_pair(
algorithm, length)
LOG.debug("SUCCESS: Asymmetric key pair generated with "
"public key uuid: %(public_uuid)s and "
"private key uuid: %(private_uuid)s" %
{'public_uuid': public_uuid,
'private_uuid': private_uuid})
private_key_metadata = {KMIPSecretStore.KEY_UUID: private_uuid}
public_key_metadata = {KMIPSecretStore.KEY_UUID: public_uuid}
passphrase_metadata = None
return ss.AsymmetricKeyMetadataDTO(private_key_metadata,
public_key_metadata,
passphrase_metadata)
except Exception as e:
LOG.exception(u._LE("Error opening or writing to client"))
raise ss.SecretGeneralException(e)
def store_secret(self, secret_dto):
"""Stores a secret
To store a secret in KMIP, the attributes must be known.
:param secret_dto: SecretDTO of the secret to be stored
:returns: Dictionary holding the key_uuid assigned by KMIP
:raises: SecretGeneralException, SecretAlgorithmNotSupportedException
"""
LOG.debug("Starting secret storage with KMIP plugin")
if not self.store_secret_supports(secret_dto.key_spec):
raise ss.SecretAlgorithmNotSupportedException(
secret_dto.key_spec.alg)
secret_type = secret_dto.type
object_type, key_format_type = (
self._map_type_ss_to_kmip(secret_type))
if object_type is None:
raise KMIPSecretStoreError(
u._('Secret object type {object_type} is '
'not supported').format(object_type=object_type))
secret = self._get_kmip_secret(secret_dto)
try:
with self.client:
LOG.debug("Opened connection to KMIP client")
uuid = self.client.register(secret)
LOG.debug("SUCCESS: Key stored with uuid: %s", uuid)
return {KMIPSecretStore.KEY_UUID: uuid}
except Exception as e:
LOG.exception(u._LE("Error opening or writing to client"))
raise ss.SecretGeneralException(e)
def get_secret(self, secret_type, secret_metadata):
"""Gets a secret
:param secret_type: secret type
:param secret_metadata: Dictionary of key metadata, requires:
{'key_uuid': <uuid of key>}
:returns: SecretDTO of the retrieved Secret
:raises: SecretGeneralException
"""
LOG.debug("Starting secret retrieval with KMIP plugin")
uuid = str(secret_metadata[KMIPSecretStore.KEY_UUID])
try:
with self.client:
LOG.debug("Opened connection to KMIP client for secret "
"retrieval")
managed_object = self.client.get(uuid)
return self._get_barbican_secret(managed_object, secret_type)
except Exception as e:
LOG.exception(u._LE("Error opening or writing to client"))
raise ss.SecretGeneralException(e)
def generate_supports(self, key_spec):
"""Key generation supported?
Specifies whether the plugin supports key generation with the
given key_spec. Currently, asymmetric key pair generation does not
support encrypting the private key with a passphrase.
Checks both the algorithm and the bit length. Only symmetric
algorithms are currently supported.
:param key_spec: KeySpec for secret to be generates
:returns: boolean indicating if secret can be generated
"""
alg_dict_entry = self.valid_alg_dict.get(key_spec.alg.lower())
if alg_dict_entry:
valid_bit_lengths = alg_dict_entry.get(
KMIPSecretStore.VALID_BIT_LENGTHS)
if (key_spec.bit_length in valid_bit_lengths
or not valid_bit_lengths):
return True
return False
def delete_secret(self, secret_metadata):
"""Deletes the secret whose metadata is included in the dictionary.
Returns nothing if successful, raises an exception if an error occurs
:param secret_metadata: Dictionary of key metadata, requires:
{'key_uuid': <uuid of key>}
:raises: SecretGeneralException
"""
LOG.debug("Starting secret deletion with KMIP plugin")
uuid = str(secret_metadata[KMIPSecretStore.KEY_UUID])
try:
with self.client:
LOG.debug("Opened connection to KMIP client")
self.client.destroy(uuid)
except Exception as e:
LOG.exception(u._LE("Error opening or writing to client"))
raise ss.SecretGeneralException(e)
def store_secret_supports(self, key_spec):
"""Key storage supported?
Specifies whether the plugin supports storage of the secret given
the attributes included in the KeySpec.
For now this always returns true if the key spec's algorithm and bit
length are not specified. The secret type may need to be added in the
future. This must always return true if the algorithm and bit length
are not specified because some secret types, like certificate, do not
require algorithm and bit length, so true must always be returned for
those cases.
:param key_spec: KeySpec of secret to be stored
:returns: boolean indicating if secret can be stored
"""
if key_spec.alg is not None and key_spec.bit_length is not None:
return self.generate_supports(key_spec)
else:
return True
def _get_kmip_secret(self, secret_dto):
"""Builds a KMIP object from a SecretDTO
This is needed for register calls. The Barbican object needs to be
converted to KMIP object before it can be stored
:param secret_dto: SecretDTO of secret to be stored
:returns: KMIP object
"""
secret_type = secret_dto.type
key_spec = secret_dto.key_spec
object_type, key_format_type = (
self._map_type_ss_to_kmip(secret_type))
normalized_secret = self._normalize_secret(secret_dto.secret,
secret_type)
kmip_object = None
if object_type == enums.ObjectType.CERTIFICATE:
kmip_object = objects.X509Certificate(normalized_secret)
elif object_type == enums.ObjectType.OPAQUE_DATA:
opaque_type = enums.OpaqueDataType.NONE
kmip_object = objects.OpaqueObject(normalized_secret,
opaque_type)
elif object_type == enums.ObjectType.PRIVATE_KEY:
algorithm = self._get_kmip_algorithm(key_spec.alg)
length = key_spec.bit_length
format_type = enums.KeyFormatType.PKCS_8
kmip_object = objects.PrivateKey(
algorithm, length, normalized_secret, format_type)
elif object_type == enums.ObjectType.PUBLIC_KEY:
algorithm = self._get_kmip_algorithm(key_spec.alg)
length = key_spec.bit_length
format_type = enums.KeyFormatType.X_509
kmip_object = objects.PublicKey(
algorithm, length, normalized_secret, format_type)
elif object_type == enums.ObjectType.SYMMETRIC_KEY:
algorithm = self._get_kmip_algorithm(key_spec.alg)
length = key_spec.bit_length
kmip_object = objects.SymmetricKey(algorithm, length,
normalized_secret)
elif object_type == enums.ObjectType.SECRET_DATA:
data_type = enums.SecretDataType.PASSWORD
kmip_object = objects.SecretData(normalized_secret, data_type)
return kmip_object
def _get_kmip_algorithm(self, ss_algorithm):
alg_entry = self.valid_alg_dict.get(ss_algorithm)
return alg_entry.get(KMIPSecretStore.KMIP_ALGORITHM_ENUM)
def _get_barbican_secret(self, managed_object, secret_type):
object_type = managed_object.object_type
secret = managed_object.value
if (object_type == enums.ObjectType.SYMMETRIC_KEY or
object_type == enums.ObjectType.PRIVATE_KEY or
object_type == enums.ObjectType.PUBLIC_KEY):
algorithm = self.kmip_barbican_alg_map[
managed_object.cryptographic_algorithm]
length = managed_object.cryptographic_length
key_spec = ss.KeySpec(algorithm, length)
else:
key_spec = ss.KeySpec()
secret = self._denormalize_secret(secret, secret_type)
secret_dto = ss.SecretDTO(
secret_type,
secret,
key_spec,
content_type=None,
transport_key=None)
return secret_dto
def _map_type_ss_to_kmip(self, object_type):
"""Map SecretType to KMIP type enum
Returns None if the type is not supported.
:param object_type: SecretType enum value
:returns: KMIP type enums if supported, None if not supported
"""
if object_type == ss.SecretType.SYMMETRIC:
return enums.ObjectType.SYMMETRIC_KEY, enums.KeyFormatType.RAW
elif object_type == ss.SecretType.PRIVATE:
if self.pkcs1_only:
return enums.ObjectType.PRIVATE_KEY, enums.KeyFormatType.PKCS_1
else:
return enums.ObjectType.PRIVATE_KEY, enums.KeyFormatType.PKCS_8
elif object_type == ss.SecretType.PUBLIC:
if self.pkcs1_only:
return enums.ObjectType.PUBLIC_KEY, enums.KeyFormatType.PKCS_1
else:
return enums.ObjectType.PUBLIC_KEY, enums.KeyFormatType.X_509
elif object_type == ss.SecretType.CERTIFICATE:
return enums.ObjectType.CERTIFICATE, enums.KeyFormatType.X_509
elif object_type == ss.SecretType.PASSPHRASE:
return enums.ObjectType.SECRET_DATA, enums.KeyFormatType.RAW
elif object_type == ss.SecretType.OPAQUE:
return enums.ObjectType.OPAQUE_DATA, enums.KeyFormatType.RAW
else:
return None, None
def _raise_secret_general_exception(self, result):
msg = u._(
"Status: {status}, Reason: {reason}, "
"Message: {message}"
).format(
status=result.result_status,
reason=result.result_reason,
message=result.result_message
)
LOG.error(u._LE("ERROR from KMIP server: %s"), msg)
raise ss.SecretGeneralException(msg)
def _validate_keyfile_permissions(self, path):
"""Check that file has permissions appropriate for a sensitive key
Key files are extremely sensitive, they should be owned by the user
who they relate to. They should be readable only (to avoid accidental
changes). They should not be readable or writable by any other user.
:raises: KMIPSecretStoreError
"""
expected = (stat.S_IRUSR | stat.S_IFREG) # 0o100400
st = os.stat(path)
if st.st_mode != expected:
raise KMIPSecretStoreError(
u._('Bad key file permissions found, expected 400 '
'for path: {file_path}').format(file_path=path)
)
def _normalize_secret(self, secret, secret_type):
"""Normalizes secret for use by KMIP plugin"""
data = base64.b64decode(secret)
if (self.pkcs1_only and
secret_type in [ss.SecretType.PUBLIC, ss.SecretType.PRIVATE]):
if secret_type == ss.SecretType.PUBLIC:
data = get_public_key_der_pkcs1(data)
elif secret_type == ss.SecretType.PRIVATE:
data = get_private_key_der_pkcs1(data)
elif secret_type in [ss.SecretType.PUBLIC,
ss.SecretType.PRIVATE,
ss.SecretType.CERTIFICATE]:
data = translations.convert_pem_to_der(data, secret_type)
return data
def _denormalize_secret(self, secret, secret_type):
"""Converts secret back to the format expected by Barbican core"""
data = secret
if secret_type in [ss.SecretType.PUBLIC,
ss.SecretType.PRIVATE,
ss.SecretType.CERTIFICATE]:
data = translations.convert_der_to_pem(data, secret_type)
return base64.b64encode(data)