openstack/deb-python-keystoneclient
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deb-python-keystoneclient/keystoneclient/middleware/auth_token.py
Adam Young 7e1700c565 replace double quotes with single. 
Change-Id: Ib2c828525fe3bafac8ed2f402a477ba62bbf6471
2014-04-21 16:55:20 -04:00

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# Copyright 2010-2012 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-BASED AUTH MIDDLEWARE
This WSGI component:
* Verifies that incoming client requests have valid tokens by validating
tokens with the auth service.
* Rejects unauthenticated requests UNLESS it is in 'delay_auth_decision'
mode, which means the final decision is delegated to the downstream WSGI
component (usually the OpenStack service)
* Collects and forwards identity information based on a valid token
such as user name, tenant, etc
Refer to: http://docs.openstack.org/developer/python-keystoneclient/
middlewarearchitecture.html
HEADERS
-------
* Headers starting with HTTP\_ is a standard http header
* Headers starting with HTTP_X is an extended http header
Coming in from initial call from client or customer
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
HTTP_X_AUTH_TOKEN
The client token being passed in.
HTTP_X_STORAGE_TOKEN
The client token being passed in (legacy Rackspace use) to support
swift/cloud files
Used for communication between components
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
WWW-Authenticate
HTTP header returned to a user indicating which endpoint to use
to retrieve a new token
What we add to the request for use by the OpenStack service
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
HTTP_X_IDENTITY_STATUS
'Confirmed' or 'Invalid'
The underlying service will only see a value of 'Invalid' if the Middleware
is configured to run in 'delay_auth_decision' mode
HTTP_X_DOMAIN_ID
Identity service managed unique identifier, string. Only present if
this is a domain-scoped v3 token.
HTTP_X_DOMAIN_NAME
Unique domain name, string. Only present if this is a domain-scoped
v3 token.
HTTP_X_PROJECT_ID
Identity service managed unique identifier, string. Only present if
this is a project-scoped v3 token, or a tenant-scoped v2 token.
HTTP_X_PROJECT_NAME
Project name, unique within owning domain, string. Only present if
this is a project-scoped v3 token, or a tenant-scoped v2 token.
HTTP_X_PROJECT_DOMAIN_ID
Identity service managed unique identifier of owning domain of
project, string. Only present if this is a project-scoped v3 token. If
this variable is set, this indicates that the PROJECT_NAME can only
be assumed to be unique within this domain.
HTTP_X_PROJECT_DOMAIN_NAME
Name of owning domain of project, string. Only present if this is a
project-scoped v3 token. If this variable is set, this indicates that
the PROJECT_NAME can only be assumed to be unique within this domain.
HTTP_X_USER_ID
Identity-service managed unique identifier, string
HTTP_X_USER_NAME
User identifier, unique within owning domain, string
HTTP_X_USER_DOMAIN_ID
Identity service managed unique identifier of owning domain of
user, string. If this variable is set, this indicates that the USER_NAME
can only be assumed to be unique within this domain.
HTTP_X_USER_DOMAIN_NAME
Name of owning domain of user, string. If this variable is set, this
indicates that the USER_NAME can only be assumed to be unique within
this domain.
HTTP_X_ROLES
Comma delimited list of case-sensitive role names
HTTP_X_SERVICE_CATALOG
json encoded keystone service catalog (optional).
HTTP_X_TENANT_ID
*Deprecated* in favor of HTTP_X_PROJECT_ID
Identity service managed unique identifier, string. For v3 tokens, this
will be set to the same value as HTTP_X_PROJECT_ID
HTTP_X_TENANT_NAME
*Deprecated* in favor of HTTP_X_PROJECT_NAME
Project identifier, unique within owning domain, string. For v3 tokens,
this will be set to the same value as HTTP_X_PROJECT_NAME
HTTP_X_TENANT
*Deprecated* in favor of HTTP_X_TENANT_ID and HTTP_X_TENANT_NAME
Keystone-assigned unique identifier, string. For v3 tokens, this
will be set to the same value as HTTP_X_PROJECT_ID
HTTP_X_USER
*Deprecated* in favor of HTTP_X_USER_ID and HTTP_X_USER_NAME
User name, unique within owning domain, string
HTTP_X_ROLE
*Deprecated* in favor of HTTP_X_ROLES
Will contain the same values as HTTP_X_ROLES.
OTHER ENVIRONMENT VARIABLES
---------------------------
keystone.token_info
Information about the token discovered in the process of
validation. This may include extended information returned by the
Keystone token validation call, as well as basic information about
the tenant and user.
"""
import contextlib
import datetime
import logging
import os
import requests
import stat
import tempfile
import time
import netaddr
from oslo.config import cfg
import six
from six.moves import urllib
from keystoneclient import access
from keystoneclient.common import cms
from keystoneclient import exceptions
from keystoneclient.middleware import memcache_crypt
from keystoneclient.openstack.common import jsonutils
from keystoneclient.openstack.common import memorycache
from keystoneclient.openstack.common import timeutils
from keystoneclient import utils
# alternative middleware configuration in the main application's
# configuration file e.g. in nova.conf
# [keystone_authtoken]
# auth_host = 127.0.0.1
# auth_port = 35357
# auth_protocol = http
# admin_tenant_name = admin
# admin_user = admin
# admin_password = badpassword
# when deploy Keystone auth_token middleware with Swift, user may elect
# to use Swift memcache instead of the local Keystone memcache. Swift memcache
# is passed in from the request environment and its identified by the
# 'swift.cache' key. However it could be different, depending on deployment.
# To use Swift memcache, you must set the 'cache' option to the environment
# key where the Swift cache object is stored.
# NOTE(jamielennox): A number of options below are deprecated however are left
# in the list and only mentioned as deprecated in the help string. This is
# because we have to provide the same deprecation functionality for arguments
# passed in via the conf in __init__ (from paste) and there is no way to test
# that the default value was set or not in CONF.
# Also if we were to remove the options from the CONF list (as typical CONF
# deprecation works) then other projects will not be able to override the
# options via CONF.
opts = [
cfg.StrOpt('auth_admin_prefix',
default='',
help='Prefix to prepend at the beginning of the path. '
'Deprecated, use identity_uri.'),
cfg.StrOpt('auth_host',
default='127.0.0.1',
help='Host providing the admin Identity API endpoint. '
'Deprecated, use identity_uri.'),
cfg.IntOpt('auth_port',
default=35357,
help='Port of the admin Identity API endpoint. '
'Deprecated, use identity_uri.'),
cfg.StrOpt('auth_protocol',
default='https',
help='Protocol of the admin Identity API endpoint '
'(http or https). Deprecated, use identity_uri.'),
cfg.StrOpt('auth_uri',
default=None,
# FIXME(dolph): should be default='http://127.0.0.1:5000/v2.0/',
# or (depending on client support) an unversioned, publicly
# accessible identity endpoint (see bug 1207517)
help='Complete public Identity API endpoint'),
cfg.StrOpt('identity_uri',
default=None,
help='Complete admin Identity API endpoint. This should '
'specify the unversioned root endpoint '
'eg. https://localhost:35357/'),
cfg.StrOpt('auth_version',
default=None,
help='API version of the admin Identity API endpoint'),
cfg.BoolOpt('delay_auth_decision',
default=False,
help='Do not handle authorization requests within the'
' middleware, but delegate the authorization decision to'
' downstream WSGI components'),
cfg.BoolOpt('http_connect_timeout',
default=None,
help='Request timeout value for communicating with Identity'
' API server.'),
cfg.IntOpt('http_request_max_retries',
default=3,
help='How many times are we trying to reconnect when'
' communicating with Identity API Server.'),
cfg.StrOpt('admin_token',
secret=True,
help='Single shared secret with the Keystone configuration'
' used for bootstrapping a Keystone installation, or otherwise'
' bypassing the normal authentication process.'),
cfg.StrOpt('admin_user',
help='Keystone account username'),
cfg.StrOpt('admin_password',
secret=True,
help='Keystone account password'),
cfg.StrOpt('admin_tenant_name',
default='admin',
help='Keystone service account tenant name to validate'
' user tokens'),
cfg.StrOpt('cache',
default=None,
help='Env key for the swift cache'),
cfg.StrOpt('certfile',
help='Required if Keystone server requires client certificate'),
cfg.StrOpt('keyfile',
help='Required if Keystone server requires client certificate'),
cfg.StrOpt('cafile', default=None,
help='A PEM encoded Certificate Authority to use when '
'verifying HTTPs connections. Defaults to system CAs.'),
cfg.BoolOpt('insecure', default=False, help='Verify HTTPS connections.'),
cfg.StrOpt('signing_dir',
help='Directory used to cache files related to PKI tokens'),
cfg.ListOpt('memcached_servers',
deprecated_name='memcache_servers',
help='Optionally specify a list of memcached server(s) to'
' use for caching. If left undefined, tokens will instead be'
' cached in-process.'),
cfg.IntOpt('token_cache_time',
default=300,
help='In order to prevent excessive effort spent validating'
' tokens, the middleware caches previously-seen tokens for a'
' configurable duration (in seconds). Set to -1 to disable'
' caching completely.'),
cfg.IntOpt('revocation_cache_time',
default=300,
help='Determines the frequency at which the list of revoked'
' tokens is retrieved from the Identity service (in seconds). A'
' high number of revocation events combined with a low cache'
' duration may significantly reduce performance.'),
cfg.StrOpt('memcache_security_strategy',
default=None,
help='(optional) if defined, indicate whether token data'
' should be authenticated or authenticated and encrypted.'
' Acceptable values are MAC or ENCRYPT. If MAC, token data is'
' authenticated (with HMAC) in the cache. If ENCRYPT, token'
' data is encrypted and authenticated in the cache. If the'
' value is not one of these options or empty, auth_token will'
' raise an exception on initialization.'),
cfg.StrOpt('memcache_secret_key',
default=None,
secret=True,
help='(optional, mandatory if memcache_security_strategy is'
' defined) this string is used for key derivation.'),
cfg.BoolOpt('include_service_catalog',
default=True,
help='(optional) indicate whether to set the X-Service-Catalog'
' header. If False, middleware will not ask for service'
' catalog on token validation and will not set the'
' X-Service-Catalog header.'),
cfg.StrOpt('enforce_token_bind',
default='permissive',
help='Used to control the use and type of token binding. Can'
' be set to: "disabled" to not check token binding.'
' "permissive" (default) to validate binding information if the'
' bind type is of a form known to the server and ignore it if'
' not. "strict" like "permissive" but if the bind type is'
' unknown the token will be rejected. "required" any form of'
' token binding is needed to be allowed. Finally the name of a'
' binding method that must be present in tokens.'),
]
CONF = cfg.CONF
CONF.register_opts(opts, group='keystone_authtoken')
LIST_OF_VERSIONS_TO_ATTEMPT = ['v2.0', 'v3.0']
CACHE_KEY_TEMPLATE = 'tokens/%s'
class BIND_MODE:
DISABLED = 'disabled'
PERMISSIVE = 'permissive'
STRICT = 'strict'
REQUIRED = 'required'
KERBEROS = 'kerberos'
def will_expire_soon(expiry):
"""Determines if expiration is about to occur.
:param expiry: a datetime of the expected expiration
:returns: boolean : true if expiration is within 30 seconds
"""
soon = (timeutils.utcnow() + datetime.timedelta(seconds=30))
return expiry < soon
def _token_is_v2(token_info):
return ('access' in token_info)
def _token_is_v3(token_info):
return ('token' in token_info)
def confirm_token_not_expired(data):
if not data:
raise InvalidUserToken('Token authorization failed')
if _token_is_v2(data):
timestamp = data['access']['token']['expires']
elif _token_is_v3(data):
timestamp = data['token']['expires_at']
else:
raise InvalidUserToken('Token authorization failed')
expires = timeutils.parse_isotime(timestamp)
expires = timeutils.normalize_time(expires)
utcnow = timeutils.utcnow()
if utcnow >= expires:
raise InvalidUserToken('Token authorization failed')
return timeutils.isotime(at=expires, subsecond=True)
def safe_quote(s):
"""URL-encode strings that are not already URL-encoded."""
return urllib.parse.quote(s) if s == urllib.parse.unquote(s) else s
class InvalidUserToken(Exception):
pass
class ServiceError(Exception):
pass
class ConfigurationError(Exception):
pass
class NetworkError(Exception):
pass
class MiniResp(object):
def __init__(self, error_message, env, headers=[]):
# The HEAD method is unique: it must never return a body, even if
# it reports an error (RFC-2616 clause 9.4). We relieve callers
# from varying the error responses depending on the method.
if env['REQUEST_METHOD'] == 'HEAD':
self.body = ['']
else:
self.body = [error_message]
self.headers = list(headers)
self.headers.append(('Content-type', 'text/plain'))
class AuthProtocol(object):
"""Auth Middleware that handles authenticating client calls."""
def __init__(self, app, conf):
self.LOG = logging.getLogger(conf.get('log_name', __name__))
self.LOG.info('Starting keystone auth_token middleware')
self.conf = conf
self.app = app
# delay_auth_decision means we still allow unauthenticated requests
# through and we let the downstream service make the final decision
self.delay_auth_decision = (self._conf_get('delay_auth_decision') in
(True, 'true', 't', '1', 'on', 'yes', 'y'))
# where to find the auth service (we use this to validate tokens)
self.identity_uri = self._conf_get('identity_uri')
self.auth_uri = self._conf_get('auth_uri')
# NOTE(jamielennox): it does appear here that our defaults arguments
# are backwards. We need to do it this way so that we can handle the
# same deprecation strategy for CONF and the conf variable.
if not self.identity_uri:
self.LOG.warning('Configuring admin URI using auth fragments. '
'This is deprecated, use \'identity_uri\''
' instead.')
auth_host = self._conf_get('auth_host')
auth_port = int(self._conf_get('auth_port'))
auth_protocol = self._conf_get('auth_protocol')
auth_admin_prefix = self._conf_get('auth_admin_prefix')
if netaddr.valid_ipv6(auth_host):
# Note(dzyu) it is an IPv6 address, so it needs to be wrapped
# with '[]' to generate a valid IPv6 URL, based on
# http://www.ietf.org/rfc/rfc2732.txt
auth_host = '[%s]' % auth_host
self.identity_uri = '%s://%s:%s' % (auth_protocol, auth_host,
auth_port)
if auth_admin_prefix:
self.identity_uri = '%s/%s' % (self.identity_uri,
auth_admin_prefix.strip('/'))
else:
self.identity_uri = self.identity_uri.rstrip('/')
if self.auth_uri is None:
self.LOG.warning(
'Configuring auth_uri to point to the public identity '
'endpoint is required; clients may not be able to '
'authenticate against an admin endpoint')
# FIXME(dolph): drop support for this fallback behavior as
# documented in bug 1207517.
# NOTE(jamielennox): we urljoin '/' to get just the base URI as
# this is the original behaviour.
self.auth_uri = urllib.parse.urljoin(self.identity_uri, '/')
self.auth_uri = self.auth_uri.rstrip('/')
# SSL
self.cert_file = self._conf_get('certfile')
self.key_file = self._conf_get('keyfile')
self.ssl_ca_file = self._conf_get('cafile')
self.ssl_insecure = self._conf_get('insecure')
# signing
self.signing_dirname = self._conf_get('signing_dir')
if self.signing_dirname is None:
self.signing_dirname = tempfile.mkdtemp(prefix='keystone-signing-')
self.LOG.info('Using %s as cache directory for signing certificate',
self.signing_dirname)
self.verify_signing_dir()
val = '%s/signing_cert.pem' % self.signing_dirname
self.signing_cert_file_name = val
val = '%s/cacert.pem' % self.signing_dirname
self.signing_ca_file_name = val
val = '%s/revoked.pem' % self.signing_dirname
self.revoked_file_name = val
# Credentials used to verify this component with the Auth service since
# validating tokens is a privileged call
self.admin_token = self._conf_get('admin_token')
self.admin_token_expiry = None
self.admin_user = self._conf_get('admin_user')
self.admin_password = self._conf_get('admin_password')
self.admin_tenant_name = self._conf_get('admin_tenant_name')
# Token caching
self._cache_pool = None
self._cache_initialized = False
# memcache value treatment, ENCRYPT or MAC
self._memcache_security_strategy = (
self._conf_get('memcache_security_strategy'))
if self._memcache_security_strategy is not None:
self._memcache_security_strategy = (
self._memcache_security_strategy.upper())
self._memcache_secret_key = (
self._conf_get('memcache_secret_key'))
self._assert_valid_memcache_protection_config()
# By default the token will be cached for 5 minutes
self.token_cache_time = int(self._conf_get('token_cache_time'))
self._token_revocation_list = None
self._token_revocation_list_fetched_time = None
self.token_revocation_list_cache_timeout = datetime.timedelta(
seconds=self._conf_get('revocation_cache_time'))
http_connect_timeout_cfg = self._conf_get('http_connect_timeout')
self.http_connect_timeout = (http_connect_timeout_cfg and
int(http_connect_timeout_cfg))
self.auth_version = None
self.http_request_max_retries = (
self._conf_get('http_request_max_retries'))
self.include_service_catalog = self._conf_get(
'include_service_catalog')
def _assert_valid_memcache_protection_config(self):
if self._memcache_security_strategy:
if self._memcache_security_strategy not in ('MAC', 'ENCRYPT'):
raise ConfigurationError('memcache_security_strategy must be '
'ENCRYPT or MAC')
if not self._memcache_secret_key:
raise ConfigurationError('memcache_secret_key must be defined '
'when a memcache_security_strategy '
'is defined')
def _init_cache(self, env):
self._cache_pool = CachePool(
env.get(self._conf_get('cache')),
self._conf_get('memcached_servers'))
self._cache_initialized = True
def _conf_get(self, name):
# try config from paste-deploy first
if name in self.conf:
return self.conf[name]
else:
return CONF.keystone_authtoken[name]
def _choose_api_version(self):
"""Determine the api version that we should use."""
# If the configuration specifies an auth_version we will just
# assume that is correct and use it. We could, of course, check
# that this version is supported by the server, but in case
# there are some problems in the field, we want as little code
# as possible in the way of letting auth_token talk to the
# server.
if self._conf_get('auth_version'):
version_to_use = self._conf_get('auth_version')
self.LOG.info('Auth Token proceeding with requested %s apis',
version_to_use)
else:
version_to_use = None
versions_supported_by_server = self._get_supported_versions()
if versions_supported_by_server:
for version in LIST_OF_VERSIONS_TO_ATTEMPT:
if version in versions_supported_by_server:
version_to_use = version
break
if version_to_use:
self.LOG.info('Auth Token confirmed use of %s apis',
version_to_use)
else:
self.LOG.error(
'Attempted versions [%s] not in list supported by '
'server [%s]',
', '.join(LIST_OF_VERSIONS_TO_ATTEMPT),
', '.join(versions_supported_by_server))
raise ServiceError('No compatible apis supported by server')
return version_to_use
def _get_supported_versions(self):
versions = []
response, data = self._json_request('GET', '/')
if response.status_code == 501:
self.LOG.warning('Old keystone installation found...assuming v2.0')
versions.append('v2.0')
elif response.status_code != 300:
self.LOG.error('Unable to get version info from keystone: %s',
response.status_code)
raise ServiceError('Unable to get version info from keystone')
else:
try:
for version in data['versions']['values']:
versions.append(version['id'])
except KeyError:
self.LOG.error(
'Invalid version response format from server')
raise ServiceError('Unable to parse version response '
'from keystone')
self.LOG.debug('Server reports support for api versions: %s',
', '.join(versions))
return versions
def __call__(self, env, start_response):
"""Handle incoming request.
Authenticate send downstream on success. Reject request if
we can't authenticate.
"""
self.LOG.debug('Authenticating user token')
# initialize memcache if we haven't done so
if not self._cache_initialized:
self._init_cache(env)
try:
self._remove_auth_headers(env)
user_token = self._get_user_token_from_header(env)
token_info = self._validate_user_token(user_token, env)
env['keystone.token_info'] = token_info
user_headers = self._build_user_headers(token_info)
self._add_headers(env, user_headers)
return self.app(env, start_response)
except InvalidUserToken:
if self.delay_auth_decision:
self.LOG.info(
'Invalid user token - deferring reject downstream')
self._add_headers(env, {'X-Identity-Status': 'Invalid'})
return self.app(env, start_response)
else:
self.LOG.info('Invalid user token - rejecting request')
return self._reject_request(env, start_response)
except ServiceError as e:
self.LOG.critical('Unable to obtain admin token: %s', e)
resp = MiniResp('Service unavailable', env)
start_response('503 Service Unavailable', resp.headers)
return resp.body
def _remove_auth_headers(self, env):
"""Remove headers so a user can't fake authentication.
:param env: wsgi request environment
"""
auth_headers = (
'X-Identity-Status',
'X-Domain-Id',
'X-Domain-Name',
'X-Project-Id',
'X-Project-Name',
'X-Project-Domain-Id',
'X-Project-Domain-Name',
'X-User-Id',
'X-User-Name',
'X-User-Domain-Id',
'X-User-Domain-Name',
'X-Roles',
'X-Service-Catalog',
# Deprecated
'X-User',
'X-Tenant-Id',
'X-Tenant-Name',
'X-Tenant',
'X-Role',
)
self.LOG.debug('Removing headers from request environment: %s',
','.join(auth_headers))
self._remove_headers(env, auth_headers)
def _get_user_token_from_header(self, env):
"""Get token id from request.
:param env: wsgi request environment
:return token id
:raises InvalidUserToken if no token is provided in request
"""
token = self._get_header(env, 'X-Auth-Token',
self._get_header(env, 'X-Storage-Token'))
if token:
return token
else:
if not self.delay_auth_decision:
self.LOG.warn('Unable to find authentication token'
' in headers')
self.LOG.debug('Headers: %s', env)
raise InvalidUserToken('Unable to find token in headers')
def _reject_request(self, env, start_response):
"""Redirect client to auth server.
:param env: wsgi request environment
:param start_response: wsgi response callback
:returns HTTPUnauthorized http response
"""
headers = [('WWW-Authenticate', 'Keystone uri=\'%s\'' % self.auth_uri)]
resp = MiniResp('Authentication required', env, headers)
start_response('401 Unauthorized', resp.headers)
return resp.body
def get_admin_token(self):
"""Return admin token, possibly fetching a new one.
if self.admin_token_expiry is set from fetching an admin token, check
it for expiration, and request a new token is the existing token
is about to expire.
:return admin token id
:raise ServiceError when unable to retrieve token from keystone
"""
if self.admin_token_expiry:
if will_expire_soon(self.admin_token_expiry):
self.admin_token = None
if not self.admin_token:
(self.admin_token,
self.admin_token_expiry) = self._request_admin_token()
return self.admin_token
def _http_request(self, method, path, **kwargs):
"""HTTP request helper used to make unspecified content type requests.
:param method: http method
:param path: relative request url
:return (http response object, response body)
:raise ServerError when unable to communicate with keystone
"""
url = '%s/%s' % (self.identity_uri, path.lstrip('/'))
kwargs.setdefault('timeout', self.http_connect_timeout)
if self.cert_file and self.key_file:
kwargs['cert'] = (self.cert_file, self.key_file)
elif self.cert_file or self.key_file:
self.LOG.warn('Cannot use only a cert or key file. '
'Please provide both. Ignoring.')
kwargs['verify'] = self.ssl_ca_file or True
if self.ssl_insecure:
kwargs['verify'] = False
RETRIES = self.http_request_max_retries
retry = 0
while True:
try:
response = requests.request(method, url, **kwargs)
break
except Exception as e:
if retry >= RETRIES:
self.LOG.error('HTTP connection exception: %s', e)
raise NetworkError('Unable to communicate with keystone')
# NOTE(vish): sleep 0.5, 1, 2
self.LOG.warn('Retrying on HTTP connection exception: %s', e)
time.sleep(2.0 ** retry / 2)
retry += 1
return response
def _json_request(self, method, path, body=None, additional_headers=None):
"""HTTP request helper used to make json requests.
:param method: http method
:param path: relative request url
:param body: dict to encode to json as request body. Optional.
:param additional_headers: dict of additional headers to send with
http request. Optional.
:return (http response object, response body parsed as json)
:raise ServerError when unable to communicate with keystone
"""
kwargs = {
'headers': {
'Content-type': 'application/json',
'Accept': 'application/json',
},
}
if additional_headers:
kwargs['headers'].update(additional_headers)
if body:
kwargs['data'] = jsonutils.dumps(body)
response = self._http_request(method, path, **kwargs)
try:
data = jsonutils.loads(response.text)
except ValueError:
self.LOG.debug('Keystone did not return json-encoded body')
data = {}
return response, data
def _request_admin_token(self):
"""Retrieve new token as admin user from keystone.
:return token id upon success
:raises ServerError when unable to communicate with keystone
Irrespective of the auth version we are going to use for the
user token, for simplicity we always use a v2 admin token to
validate the user token.
"""
params = {
'auth': {
'passwordCredentials': {
'username': self.admin_user,
'password': self.admin_password,
},
'tenantName': self.admin_tenant_name,
}
}
response, data = self._json_request('POST',
'/v2.0/tokens',
body=params)
try:
token = data['access']['token']['id']
expiry = data['access']['token']['expires']
if not (token and expiry):
raise AssertionError('invalid token or expire')
datetime_expiry = timeutils.parse_isotime(expiry)
return (token, timeutils.normalize_time(datetime_expiry))
except (AssertionError, KeyError):
self.LOG.warn(
'Unexpected response from keystone service: %s', data)
raise ServiceError('invalid json response')
except (ValueError):
data['access']['token']['id'] = '<SANITIZED>'
self.LOG.warn(
'Unable to parse expiration time from token: %s', data)
raise ServiceError('invalid json response')
def _validate_user_token(self, user_token, env, retry=True):
"""Authenticate user using PKI
:param user_token: user's token id
:param retry: Ignored, as it is not longer relevant
:return uncrypted body of the token if the token is valid
:raise InvalidUserToken if token is rejected
:no longer raises ServiceError since it no longer makes RPC
"""
token_id = None
try:
token_id = cms.cms_hash_token(user_token)
cached = self._cache_get(token_id)
if cached:
return cached
if cms.is_asn1_token(user_token):
verified = self.verify_signed_token(user_token)
data = jsonutils.loads(verified)
else:
data = self.verify_uuid_token(user_token, retry)
expires = confirm_token_not_expired(data)
self._confirm_token_bind(data, env)
self._cache_put(token_id, data, expires)
return data
except NetworkError:
self.LOG.debug('Token validation failure.', exc_info=True)
self.LOG.warn('Authorization failed for token')
raise InvalidUserToken('Token authorization failed')
except Exception:
self.LOG.debug('Token validation failure.', exc_info=True)
if token_id:
self._cache_store_invalid(token_id)
self.LOG.warn('Authorization failed for token')
raise InvalidUserToken('Token authorization failed')
def _build_user_headers(self, token_info):
"""Convert token object into headers.
Build headers that represent authenticated user - see main
doc info at start of file for details of headers to be defined.
:param token_info: token object returned by keystone on authentication
:raise InvalidUserToken when unable to parse token object
"""
auth_ref = access.AccessInfo.factory(body=token_info)
roles = ','.join(auth_ref.role_names)
if _token_is_v2(token_info) and not auth_ref.project_id:
raise InvalidUserToken('Unable to determine tenancy.')
rval = {
'X-Identity-Status': 'Confirmed',
'X-Domain-Id': auth_ref.domain_id,
'X-Domain-Name': auth_ref.domain_name,
'X-Project-Id': auth_ref.project_id,
'X-Project-Name': auth_ref.project_name,
'X-Project-Domain-Id': auth_ref.project_domain_id,
'X-Project-Domain-Name': auth_ref.project_domain_name,
'X-User-Id': auth_ref.user_id,
'X-User-Name': auth_ref.username,
'X-User-Domain-Id': auth_ref.user_domain_id,
'X-User-Domain-Name': auth_ref.user_domain_name,
'X-Roles': roles,
# Deprecated
'X-User': auth_ref.username,
'X-Tenant-Id': auth_ref.project_id,
'X-Tenant-Name': auth_ref.project_name,
'X-Tenant': auth_ref.project_name,
'X-Role': roles,
}
self.LOG.debug('Received request from user: %s with project_id : %s'
' and roles: %s ',
auth_ref.user_id, auth_ref.project_id, roles)
if self.include_service_catalog and auth_ref.has_service_catalog():
catalog = auth_ref.service_catalog.get_data()
rval['X-Service-Catalog'] = jsonutils.dumps(catalog)
return rval
def _header_to_env_var(self, key):
"""Convert header to wsgi env variable.
:param key: http header name (ex. 'X-Auth-Token')
:return wsgi env variable name (ex. 'HTTP_X_AUTH_TOKEN')
"""
return 'HTTP_%s' % key.replace('-', '_').upper()
def _add_headers(self, env, headers):
"""Add http headers to environment."""
for (k, v) in six.iteritems(headers):
env_key = self._header_to_env_var(k)
env[env_key] = v
def _remove_headers(self, env, keys):
"""Remove http headers from environment."""
for k in keys:
env_key = self._header_to_env_var(k)
try:
del env[env_key]
except KeyError:
pass
def _get_header(self, env, key, default=None):
"""Get http header from environment."""
env_key = self._header_to_env_var(key)
return env.get(env_key, default)
def _cache_get(self, token_id, ignore_expires=False):
"""Return token information from cache.
If token is invalid raise InvalidUserToken
return token only if fresh (not expired).
"""
if token_id:
if self._memcache_security_strategy is None:
key = CACHE_KEY_TEMPLATE % token_id
with self._cache_pool.reserve() as cache:
serialized = cache.get(key)
else:
secret_key = self._memcache_secret_key
if isinstance(secret_key, six.string_types):
secret_key = secret_key.encode('utf-8')
security_strategy = self._memcache_security_strategy
if isinstance(security_strategy, six.string_types):
security_strategy = security_strategy.encode('utf-8')
keys = memcache_crypt.derive_keys(
token_id,
secret_key,
security_strategy)
cache_key = CACHE_KEY_TEMPLATE % (
memcache_crypt.get_cache_key(keys))
with self._cache_pool.reserve() as cache:
raw_cached = cache.get(cache_key)
try:
# unprotect_data will return None if raw_cached is None
serialized = memcache_crypt.unprotect_data(keys,
raw_cached)
except Exception:
msg = 'Failed to decrypt/verify cache data'
self.LOG.exception(msg)
# this should have the same effect as data not
# found in cache
serialized = None
if serialized is None:
return None
# Note that 'invalid' and (data, expires) are the only
# valid types of serialized cache entries, so there is not
# a collision with jsonutils.loads(serialized) == None.
if not isinstance(serialized, six.string_types):
serialized = serialized.decode('utf-8')
cached = jsonutils.loads(serialized)
if cached == 'invalid':
self.LOG.debug('Cached Token is marked unauthorized')
raise InvalidUserToken('Token authorization failed')
data, expires = cached
try:
expires = timeutils.parse_isotime(expires)
except ValueError:
# Gracefully handle upgrade of expiration times from *nix
# timestamps to ISO 8601 formatted dates by ignoring old cached
# values.
return
expires = timeutils.normalize_time(expires)
utcnow = timeutils.utcnow()
if ignore_expires or utcnow < expires:
self.LOG.debug('Returning cached token')
return data
else:
self.LOG.debug('Cached Token seems expired')
def _cache_store(self, token_id, data):
"""Store value into memcache.
data may be the string 'invalid' or a tuple like (data, expires)
"""
serialized_data = jsonutils.dumps(data)
if isinstance(serialized_data, six.text_type):
serialized_data = serialized_data.encode('utf-8')
if self._memcache_security_strategy is None:
cache_key = CACHE_KEY_TEMPLATE % token_id
data_to_store = serialized_data
else:
secret_key = self._memcache_secret_key
if isinstance(secret_key, six.string_types):
secret_key = secret_key.encode('utf-8')
security_strategy = self._memcache_security_strategy
if isinstance(security_strategy, six.string_types):
security_strategy = security_strategy.encode('utf-8')
keys = memcache_crypt.derive_keys(
token_id, secret_key, security_strategy)
cache_key = CACHE_KEY_TEMPLATE % memcache_crypt.get_cache_key(keys)
data_to_store = memcache_crypt.protect_data(keys, serialized_data)
with self._cache_pool.reserve() as cache:
cache.set(cache_key, data_to_store, time=self.token_cache_time)
def _invalid_user_token(self, msg=False):
# NOTE(jamielennox): use False as the default so that None is valid
if msg is False:
msg = 'Token authorization failed'
raise InvalidUserToken(msg)
def _confirm_token_bind(self, data, env):
bind_mode = self._conf_get('enforce_token_bind')
if bind_mode == BIND_MODE.DISABLED:
return
try:
if _token_is_v2(data):
bind = data['access']['token']['bind']
elif _token_is_v3(data):
bind = data['token']['bind']
else:
self._invalid_user_token()
except KeyError:
bind = {}
# permissive and strict modes don't require there to be a bind
permissive = bind_mode in (BIND_MODE.PERMISSIVE, BIND_MODE.STRICT)
if not bind:
if permissive:
# no bind provided and none required
return
else:
self.LOG.info('No bind information present in token.')
self._invalid_user_token()
# get the named mode if bind_mode is not one of the predefined
if permissive or bind_mode == BIND_MODE.REQUIRED:
name = None
else:
name = bind_mode
if name and name not in bind:
self.LOG.info('Named bind mode %s not in bind information', name)
self._invalid_user_token()
for bind_type, identifier in six.iteritems(bind):
if bind_type == BIND_MODE.KERBEROS:
if not env.get('AUTH_TYPE', '').lower() == 'negotiate':
self.LOG.info('Kerberos credentials required and '
'not present.')
self._invalid_user_token()
if not env.get('REMOTE_USER') == identifier:
self.LOG.info('Kerberos credentials do not match '
'those in bind.')
self._invalid_user_token()
self.LOG.debug('Kerberos bind authentication successful.')
elif bind_mode == BIND_MODE.PERMISSIVE:
self.LOG.debug('Ignoring Unknown bind for permissive mode: '
'%(bind_type)s: %(identifier)s.',
{'bind_type': bind_type,
'identifier': identifier})
else:
self.LOG.info('Couldn`t verify unknown bind: %(bind_type)s: '
'%(identifier)s.',
{'bind_type': bind_type,
'identifier': identifier})
self._invalid_user_token()
def _cache_put(self, token_id, data, expires):
"""Put token data into the cache.
Stores the parsed expire date in cache allowing
quick check of token freshness on retrieval.
"""
self.LOG.debug('Storing token in cache')
self._cache_store(token_id, (data, expires))
def _cache_store_invalid(self, token_id):
"""Store invalid token in cache."""
self.LOG.debug('Marking token as unauthorized in cache')
self._cache_store(token_id, 'invalid')
def verify_uuid_token(self, user_token, retry=True):
"""Authenticate user token with keystone.
:param user_token: user's token id
:param retry: flag that forces the middleware to retry
user authentication when an indeterminate
response is received. Optional.
:return: token object received from keystone on success
:raise InvalidUserToken: if token is rejected
:raise ServiceError: if unable to authenticate token
"""
# Determine the highest api version we can use.
if not self.auth_version:
self.auth_version = self._choose_api_version()
if self.auth_version == 'v3.0':
headers = {'X-Auth-Token': self.get_admin_token(),
'X-Subject-Token': safe_quote(user_token)}
path = '/v3/auth/tokens'
if not self.include_service_catalog:
# NOTE(gyee): only v3 API support this option
path = path + '?nocatalog'
response, data = self._json_request(
'GET',
path,
additional_headers=headers)
else:
headers = {'X-Auth-Token': self.get_admin_token()}
response, data = self._json_request(
'GET',
'/v2.0/tokens/%s' % safe_quote(user_token),
additional_headers=headers)
if response.status_code == 200:
return data
if response.status_code == 404:
self.LOG.warn('Authorization failed for token')
raise InvalidUserToken('Token authorization failed')
if response.status_code == 401:
self.LOG.info(
'Keystone rejected admin token, resetting')
self.admin_token = None
else:
self.LOG.error('Bad response code while validating token: %s',
response.status_code)
if retry:
self.LOG.info('Retrying validation')
return self.verify_uuid_token(user_token, False)
else:
self.LOG.warn('Invalid user token. Keystone response: %s', data)
raise InvalidUserToken()
def is_signed_token_revoked(self, signed_text):
"""Indicate whether the token appears in the revocation list."""
revocation_list = self.token_revocation_list
revoked_tokens = revocation_list.get('revoked', [])
if not revoked_tokens:
return
revoked_ids = (x['id'] for x in revoked_tokens)
if isinstance(signed_text, six.text_type):
signed_text = signed_text.encode('utf-8')
token_id = utils.hash_signed_token(signed_text)
for revoked_id in revoked_ids:
if token_id == revoked_id:
self.LOG.debug('Token is marked as having been revoked')
return True
return False
def cms_verify(self, data):
"""Verifies the signature of the provided data's IAW CMS syntax.
If either of the certificate files might be missing, fetch them and
retry.
"""
def verify():
try:
return cms.cms_verify(data, self.signing_cert_file_name,
self.signing_ca_file_name)
except cms.subprocess.CalledProcessError as err:
self.LOG.warning('Verify error: %s', err)
raise
try:
return verify()
except exceptions.CertificateConfigError:
# the certs might be missing; unconditionally fetch to avoid racing
self.fetch_signing_cert()
self.fetch_ca_cert()
try:
# retry with certs in place
return verify()
except exceptions.CertificateConfigError as err:
# if this is still occurring, something else is wrong and we
# need err.output to identify the problem
self.LOG.error('CMS Verify output: %s', err.output)
raise
def verify_signed_token(self, signed_text):
"""Check that the token is unrevoked and has a valid signature."""
if self.is_signed_token_revoked(signed_text):
raise InvalidUserToken('Token has been revoked')
formatted = cms.token_to_cms(signed_text)
return self.cms_verify(formatted)
def verify_signing_dir(self):
if os.path.exists(self.signing_dirname):
if not os.access(self.signing_dirname, os.W_OK):
raise ConfigurationError(
'unable to access signing_dir %s' % self.signing_dirname)
uid = os.getuid()
if os.stat(self.signing_dirname).st_uid != uid:
self.LOG.warning(
'signing_dir is not owned by %s', uid)
current_mode = stat.S_IMODE(os.stat(self.signing_dirname).st_mode)
if current_mode != stat.S_IRWXU:
self.LOG.warning(
'signing_dir mode is %s instead of %s',
oct(current_mode), oct(stat.S_IRWXU))
else:
os.makedirs(self.signing_dirname, stat.S_IRWXU)
@property
def token_revocation_list_fetched_time(self):
if not self._token_revocation_list_fetched_time:
# If the fetched list has been written to disk, use its
# modification time.
if os.path.exists(self.revoked_file_name):
mtime = os.path.getmtime(self.revoked_file_name)
fetched_time = datetime.datetime.utcfromtimestamp(mtime)
# Otherwise the list will need to be fetched.
else:
fetched_time = datetime.datetime.min
self._token_revocation_list_fetched_time = fetched_time
return self._token_revocation_list_fetched_time
@token_revocation_list_fetched_time.setter
def token_revocation_list_fetched_time(self, value):
self._token_revocation_list_fetched_time = value
@property
def token_revocation_list(self):
timeout = (self.token_revocation_list_fetched_time +
self.token_revocation_list_cache_timeout)
list_is_current = timeutils.utcnow() < timeout
if list_is_current:
# Load the list from disk if required
if not self._token_revocation_list:
open_kwargs = {'encoding': 'utf-8'} if six.PY3 else {}
with open(self.revoked_file_name, 'r', **open_kwargs) as f:
self._token_revocation_list = jsonutils.loads(f.read())
else:
self.token_revocation_list = self.fetch_revocation_list()
return self._token_revocation_list
def _atomic_write_to_signing_dir(self, file_name, value):
# In Python2, encoding is slow so the following check avoids it if it
# is not absolutely necessary.
if isinstance(value, six.text_type):
value = value.encode('utf-8')
def _atomic_write(destination, data):
with tempfile.NamedTemporaryFile(dir=self.signing_dirname,
delete=False) as f:
f.write(data)
os.rename(f.name, destination)
try:
_atomic_write(file_name, value)
except (OSError, IOError):
self.verify_signing_dir()
_atomic_write(file_name, value)
@token_revocation_list.setter
def token_revocation_list(self, value):
"""Save a revocation list to memory and to disk.
:param value: A json-encoded revocation list
"""
self._token_revocation_list = jsonutils.loads(value)
self.token_revocation_list_fetched_time = timeutils.utcnow()
self._atomic_write_to_signing_dir(self.revoked_file_name, value)
def fetch_revocation_list(self, retry=True):
headers = {'X-Auth-Token': self.get_admin_token()}
response, data = self._json_request('GET', '/v2.0/tokens/revoked',
additional_headers=headers)
if response.status_code == 401:
if retry:
self.LOG.info(
'Keystone rejected admin token, resetting admin token')
self.admin_token = None
return self.fetch_revocation_list(retry=False)
if response.status_code != 200:
raise ServiceError('Unable to fetch token revocation list.')
if 'signed' not in data:
raise ServiceError('Revocation list improperly formatted.')
return self.cms_verify(data['signed'])
def _fetch_cert_file(self, cert_file_name, cert_type):
if not self.auth_version:
self.auth_version = self._choose_api_version()
if self.auth_version == 'v3.0':
if cert_type == 'signing':
cert_type = 'certificates'
path = '/v3/OS-SIMPLE-CERT/' + cert_type
else:
path = '/v2.0/certificates/' + cert_type
response = self._http_request('GET', path)
if response.status_code != 200:
raise exceptions.CertificateConfigError(response.text)
self._atomic_write_to_signing_dir(cert_file_name, response.text)
def fetch_signing_cert(self):
self._fetch_cert_file(self.signing_cert_file_name, 'signing')
def fetch_ca_cert(self):
self._fetch_cert_file(self.signing_ca_file_name, 'ca')
class CachePool(list):
"""A lazy pool of cache references."""
def __init__(self, cache, memcached_servers):
self._environment_cache = cache
self._memcached_servers = memcached_servers
@contextlib.contextmanager
def reserve(self):
"""Context manager to manage a pooled cache reference."""
if self._environment_cache is not None:
# skip pooling and just use the cache from the upstream filter
yield self._environment_cache
return # otherwise the context manager will continue!
try:
c = self.pop()
except IndexError:
# the pool is empty, so we need to create a new client
c = memorycache.get_client(self._memcached_servers)
try:
yield c
finally:
self.append(c)
def filter_factory(global_conf, **local_conf):
"""Returns a WSGI filter app for use with paste.deploy."""
conf = global_conf.copy()
conf.update(local_conf)
def auth_filter(app):
return AuthProtocol(app, conf)
return auth_filter
def app_factory(global_conf, **local_conf):
conf = global_conf.copy()
conf.update(local_conf)
return AuthProtocol(None, conf)
if __name__ == '__main__':
"""Run this module directly to start a protected echo service::
$ python -m keystoneclient.middleware.auth_token
When the ``auth_token`` module authenticates a request, the echo service
will respond with all the environment variables presented to it by this
module.
"""
def echo_app(environ, start_response):
"""A WSGI application that echoes the CGI environment to the user."""
start_response('200 OK', [('Content-Type', 'application/json')])
environment = dict((k, v) for k, v in six.iteritems(environ)
if k.startswith('HTTP_X_'))
yield jsonutils.dumps(environment)
from wsgiref import simple_server
# hardcode any non-default configuration here
conf = {'auth_protocol': 'http', 'admin_token': 'ADMIN'}
app = AuthProtocol(echo_app, conf)
server = simple_server.make_server('', 8000, app)
print('Serving on port 8000 (Ctrl+C to end)...')
server.serve_forever()
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