swift/swift/common/middleware/s3api/s3token.py

325 lines
13 KiB
Python

# Copyright 2012 OpenStack Foundation
# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# Copyright 2011,2012 Akira YOSHIYAMA <akirayoshiyama@gmail.com>
# 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.
# This source code is based ./auth_token.py and ./ec2_token.py.
# See them for their copyright.
"""
-------------------
S3 Token Middleware
-------------------
s3token middleware is for authentication with s3api + keystone.
This middleware:
* Gets a request from the s3api middleware with an S3 Authorization
access key.
* Validates s3 token with Keystone.
* Transforms the account name to AUTH_%(tenant_name).
"""
import base64
import json
import requests
import six
from six.moves import urllib
from swift.common.swob import Request, HTTPBadRequest, HTTPUnauthorized, \
HTTPException
from swift.common.utils import config_true_value, split_path, get_logger
from swift.common.wsgi import ConfigFileError
PROTOCOL_NAME = 'S3 Token Authentication'
# Headers to purge if they came from (or may have come from) the client
KEYSTONE_AUTH_HEADERS = (
'X-Identity-Status', 'X-Service-Identity-Status',
'X-Domain-Id', 'X-Service-Domain-Id',
'X-Domain-Name', 'X-Service-Domain-Name',
'X-Project-Id', 'X-Service-Project-Id',
'X-Project-Name', 'X-Service-Project-Name',
'X-Project-Domain-Id', 'X-Service-Project-Domain-Id',
'X-Project-Domain-Name', 'X-Service-Project-Domain-Name',
'X-User-Id', 'X-Service-User-Id',
'X-User-Name', 'X-Service-User-Name',
'X-User-Domain-Id', 'X-Service-User-Domain-Id',
'X-User-Domain-Name', 'X-Service-User-Domain-Name',
'X-Roles', 'X-Service-Roles',
'X-Is-Admin-Project',
'X-Service-Catalog',
# Deprecated headers, too...
'X-Tenant-Id',
'X-Tenant-Name',
'X-Tenant',
'X-User',
'X-Role',
)
def parse_v2_response(token):
access_info = token['access']
headers = {
'X-Identity-Status': 'Confirmed',
'X-Roles': ','.join(r['name']
for r in access_info['user']['roles']),
'X-User-Id': access_info['user']['id'],
'X-User-Name': access_info['user']['name'],
'X-Tenant-Id': access_info['token']['tenant']['id'],
'X-Tenant-Name': access_info['token']['tenant']['name'],
'X-Project-Id': access_info['token']['tenant']['id'],
'X-Project-Name': access_info['token']['tenant']['name'],
}
return (
headers,
access_info['token'].get('id'),
access_info['token']['tenant'])
def parse_v3_response(token):
token = token['token']
headers = {
'X-Identity-Status': 'Confirmed',
'X-Roles': ','.join(r['name']
for r in token['roles']),
'X-User-Id': token['user']['id'],
'X-User-Name': token['user']['name'],
'X-User-Domain-Id': token['user']['domain']['id'],
'X-User-Domain-Name': token['user']['domain']['name'],
'X-Tenant-Id': token['project']['id'],
'X-Tenant-Name': token['project']['name'],
'X-Project-Id': token['project']['id'],
'X-Project-Name': token['project']['name'],
'X-Project-Domain-Id': token['project']['domain']['id'],
'X-Project-Domain-Name': token['project']['domain']['name'],
}
return headers, None, token['project']
class S3Token(object):
"""Middleware that handles S3 authentication."""
def __init__(self, app, conf):
"""Common initialization code."""
self._app = app
self._logger = get_logger(
conf, log_route=conf.get('log_name', 's3token'))
self._logger.debug('Starting the %s component', PROTOCOL_NAME)
self._timeout = float(conf.get('http_timeout', '10.0'))
if not (0 < self._timeout <= 60):
raise ValueError('http_timeout must be between 0 and 60 seconds')
self._reseller_prefix = conf.get('reseller_prefix', 'AUTH_')
self._delay_auth_decision = config_true_value(
conf.get('delay_auth_decision'))
# where to find the auth service (we use this to validate tokens)
self._request_uri = conf.get('auth_uri', '').rstrip('/') + '/s3tokens'
parsed = urllib.parse.urlsplit(self._request_uri)
if not parsed.scheme or not parsed.hostname:
raise ConfigFileError(
'Invalid auth_uri; must include scheme and host')
if parsed.scheme not in ('http', 'https'):
raise ConfigFileError(
'Invalid auth_uri; scheme must be http or https')
if parsed.query or parsed.fragment or '@' in parsed.netloc:
raise ConfigFileError('Invalid auth_uri; must not include '
'username, query, or fragment')
# SSL
insecure = config_true_value(conf.get('insecure'))
cert_file = conf.get('certfile')
key_file = conf.get('keyfile')
if insecure:
self._verify = False
elif cert_file and key_file:
self._verify = (cert_file, key_file)
elif cert_file:
self._verify = cert_file
else:
self._verify = None
def _deny_request(self, code):
error_cls, message = {
'AccessDenied': (HTTPUnauthorized, 'Access denied'),
'InvalidURI': (HTTPBadRequest,
'Could not parse the specified URI'),
}[code]
resp = error_cls(content_type='text/xml')
error_msg = ('<?xml version="1.0" encoding="UTF-8"?>\r\n'
'<Error>\r\n <Code>%s</Code>\r\n '
'<Message>%s</Message>\r\n</Error>\r\n' %
(code, message))
if six.PY3:
error_msg = error_msg.encode()
resp.body = error_msg
return resp
def _json_request(self, creds_json):
headers = {'Content-Type': 'application/json'}
try:
response = requests.post(self._request_uri,
headers=headers, data=creds_json,
verify=self._verify,
timeout=self._timeout)
except requests.exceptions.RequestException as e:
self._logger.info('HTTP connection exception: %s', e)
raise self._deny_request('InvalidURI')
if response.status_code < 200 or response.status_code >= 300:
self._logger.debug('Keystone reply error: status=%s reason=%s',
response.status_code, response.reason)
raise self._deny_request('AccessDenied')
return response
def __call__(self, environ, start_response):
"""Handle incoming request. authenticate and send downstream."""
req = Request(environ)
self._logger.debug('Calling S3Token middleware.')
# Always drop auth headers if we're first in the pipeline
if 'keystone.token_info' not in req.environ:
req.headers.update({h: None for h in KEYSTONE_AUTH_HEADERS})
try:
parts = split_path(req.path, 1, 4, True)
version, account, container, obj = parts
except ValueError:
msg = 'Not a path query: %s, skipping.' % req.path
self._logger.debug(msg)
return self._app(environ, start_response)
# Read request signature and access id.
s3_auth_details = req.environ.get('s3api.auth_details')
if not s3_auth_details:
msg = 'No authorization details from s3api. skipping.'
self._logger.debug(msg)
return self._app(environ, start_response)
access = s3_auth_details['access_key']
if isinstance(access, six.binary_type):
access = access.decode('utf-8')
signature = s3_auth_details['signature']
if isinstance(signature, six.binary_type):
signature = signature.decode('utf-8')
string_to_sign = s3_auth_details['string_to_sign']
if isinstance(string_to_sign, six.text_type):
string_to_sign = string_to_sign.encode('utf-8')
token = base64.urlsafe_b64encode(string_to_sign).encode('ascii')
# NOTE(chmou): This is to handle the special case with nova
# when we have the option s3_affix_tenant. We will force it to
# connect to another account than the one
# authenticated. Before people start getting worried about
# security, I should point that we are connecting with
# username/token specified by the user but instead of
# connecting to its own account we will force it to go to an
# another account. In a normal scenario if that user don't
# have the reseller right it will just fail but since the
# reseller account can connect to every account it is allowed
# by the swift_auth middleware.
force_tenant = None
if ':' in access:
access, force_tenant = access.split(':')
# Authenticate request.
creds = {'credentials': {'access': access,
'token': token,
'signature': signature}}
creds_json = json.dumps(creds)
self._logger.debug('Connecting to Keystone sending this JSON: %s',
creds_json)
# NOTE(vish): We could save a call to keystone by having
# keystone return token, tenant, user, and roles
# from this call.
#
# NOTE(chmou): We still have the same problem we would need to
# change token_auth to detect if we already
# identified and not doing a second query and just
# pass it through to swiftauth in this case.
try:
# NB: requests.Response, not swob.Response
resp = self._json_request(creds_json)
except HTTPException as e_resp:
if self._delay_auth_decision:
msg = 'Received error, deferring rejection based on error: %s'
self._logger.debug(msg, e_resp.status)
return self._app(environ, start_response)
else:
msg = 'Received error, rejecting request with error: %s'
self._logger.debug(msg, e_resp.status)
# NB: swob.Response, not requests.Response
return e_resp(environ, start_response)
self._logger.debug('Keystone Reply: Status: %d, Output: %s',
resp.status_code, resp.content)
try:
token = resp.json()
if 'access' in token:
headers, token_id, tenant = parse_v2_response(token)
elif 'token' in token:
headers, token_id, tenant = parse_v3_response(token)
else:
raise ValueError
# Populate the environment similar to auth_token,
# so we don't have to contact Keystone again.
#
# Note that although the strings are unicode following json
# deserialization, Swift's HeaderEnvironProxy handles ensuring
# they're stored as native strings
req.headers.update(headers)
req.environ['keystone.token_info'] = token
except (ValueError, KeyError, TypeError):
if self._delay_auth_decision:
error = ('Error on keystone reply: %d %s - '
'deferring rejection downstream')
self._logger.debug(error, resp.status_code, resp.content)
return self._app(environ, start_response)
else:
error = ('Error on keystone reply: %d %s - '
'rejecting request')
self._logger.debug(error, resp.status_code, resp.content)
return self._deny_request('InvalidURI')(
environ, start_response)
req.headers['X-Auth-Token'] = token_id
tenant_to_connect = force_tenant or tenant['id']
if six.PY2 and isinstance(tenant_to_connect, six.text_type):
tenant_to_connect = tenant_to_connect.encode('utf-8')
self._logger.debug('Connecting with tenant: %s', tenant_to_connect)
new_tenant_name = '%s%s' % (self._reseller_prefix, tenant_to_connect)
environ['PATH_INFO'] = environ['PATH_INFO'].replace(account,
new_tenant_name)
return self._app(environ, start_response)
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 S3Token(app, conf)
return auth_filter