keystonemiddleware/keystonemiddleware/ec2_token.py
Janonymous f4d453ec30 use oslo.log instead of logging
The constants of log levels were added in the 1.8 version
of the oslo.log library.
So we can replace all usage of system logging module
with log module from oslo.log

Change-Id: I97a1d913b543dc9dbd4d228b04adbdf7ee320df5
2017-01-13 03:24:18 +00:00

219 lines
8.0 KiB
Python

# Copyright 2012 OpenStack Foundation
# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# 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.
"""Starting point for routing EC2 requests."""
import hashlib
from oslo_config import cfg
from oslo_log import log as logging
from oslo_serialization import jsonutils
import requests
import six
import webob.dec
from keystonemiddleware.i18n import _
keystone_ec2_opts = [
cfg.StrOpt('url',
default='http://localhost:5000/v2.0/ec2tokens',
help='URL to get token from ec2 request.'),
cfg.StrOpt('keyfile',
help='Required if EC2 server requires client certificate.'),
cfg.StrOpt('certfile',
help='Client certificate key filename. Required if EC2 server '
'requires client certificate.'),
cfg.StrOpt('cafile',
help='A PEM encoded certificate authority to use when '
'verifying HTTPS connections. Defaults to the system '
'CAs.'),
cfg.BoolOpt('insecure', default=False,
help='Disable SSL certificate verification.'),
]
CONF = cfg.CONF
CONF.register_opts(keystone_ec2_opts, group='keystone_ec2_token')
PROTOCOL_NAME = 'EC2 Token Authentication'
class EC2Token(object):
"""Authenticate an EC2 request with keystone and convert to token."""
def __init__(self, application, conf):
super(EC2Token, self).__init__()
self._application = application
self._logger = logging.getLogger(conf.get('log_name', __name__))
self._logger.debug('Starting the %s component', PROTOCOL_NAME)
def _ec2_error_response(self, code, message):
"""Helper to construct an EC2 compatible error message."""
self._logger.debug('EC2 error response: %(code)s: %(message)s',
{'code': code, 'message': message})
resp = webob.Response()
resp.status = 400
resp.headers['Content-Type'] = 'text/xml'
error_msg = str('<?xml version="1.0"?>\n'
'<Response><Errors><Error><Code>%s</Code>'
'<Message>%s</Message></Error></Errors></Response>' %
(code, message))
if six.PY3:
error_msg = error_msg.encode()
resp.body = error_msg
return resp
def _get_signature(self, req):
"""Extract the signature from the request.
This can be a get/post variable or for version 4 also in a header
called 'Authorization'.
- params['Signature'] == version 0,1,2,3
- params['X-Amz-Signature'] == version 4
- header 'Authorization' == version 4
"""
sig = req.params.get('Signature') or req.params.get('X-Amz-Signature')
if sig is None and 'Authorization' in req.headers:
auth_str = req.headers['Authorization']
sig = auth_str.partition("Signature=")[2].split(',')[0]
return sig
def _get_access(self, req):
"""Extract the access key identifier.
For version 0/1/2/3 this is passed as the AccessKeyId parameter, for
version 4 it is either an X-Amz-Credential parameter or a Credential=
field in the 'Authorization' header string.
"""
access = req.params.get('AWSAccessKeyId')
if access is None:
cred_param = req.params.get('X-Amz-Credential')
if cred_param:
access = cred_param.split("/")[0]
if access is None and 'Authorization' in req.headers:
auth_str = req.headers['Authorization']
cred_str = auth_str.partition("Credential=")[2].split(',')[0]
access = cred_str.split("/")[0]
return access
@webob.dec.wsgify()
def __call__(self, req):
# NOTE(alevine): We need to calculate the hash here because
# subsequent access to request modifies the req.body so the hash
# calculation will yield invalid results.
body_hash = hashlib.sha256(req.body).hexdigest()
signature = self._get_signature(req)
if not signature:
msg = _("Signature not provided")
return self._ec2_error_response("AuthFailure", msg)
access = self._get_access(req)
if not access:
msg = _("Access key not provided")
return self._ec2_error_response("AuthFailure", msg)
if 'X-Amz-Signature' in req.params or 'Authorization' in req.headers:
auth_params = {}
else:
# Make a copy of args for authentication and signature verification
auth_params = dict(req.params)
# Not part of authentication args
auth_params.pop('Signature', None)
headers = req.headers
if six.PY3:
# NOTE(andrey-mp): jsonutils dumps it as list of keys without
# conversion instead real dict
headers = {k: headers[k] for k in headers}
cred_dict = {
'access': access,
'signature': signature,
'host': req.host,
'verb': req.method,
'path': req.path,
'params': auth_params,
'headers': headers,
'body_hash': body_hash
}
if "ec2" in CONF.keystone_ec2_token.url:
creds = {'ec2Credentials': cred_dict}
else:
creds = {'auth': {'OS-KSEC2:ec2Credentials': cred_dict}}
creds_json = jsonutils.dumps(creds)
headers = {'Content-Type': 'application/json'}
verify = not CONF.keystone_ec2_token.insecure
if verify and CONF.keystone_ec2_token.cafile:
verify = CONF.keystone_ec2_token.cafile
cert = None
if (CONF.keystone_ec2_token.certfile and
CONF.keystone_ec2_token.keyfile):
cert = (CONF.keystone_ec2_certfile,
CONF.keystone_ec2_token.keyfile)
elif CONF.keystone_ec2_token.certfile:
cert = CONF.keystone_ec2_token.certfile
response = requests.request('POST', CONF.keystone_ec2_token.url,
data=creds_json, headers=headers,
verify=verify, cert=cert)
# NOTE(vish): We could save a call to keystone by
# having keystone return token, tenant,
# user, and roles from this call.
status_code = response.status_code
if status_code != 200:
msg = _('Error response from keystone: %s') % response.reason
self._logger.debug(msg)
return self._ec2_error_response("AuthFailure", msg)
result = response.json()
try:
if 'token' in result:
# NOTE(andrey-mp): response from keystone v3
token_id = response.headers['x-subject-token']
else:
token_id = result['access']['token']['id']
except (AttributeError, KeyError):
msg = _("Failure parsing response from keystone")
self._logger.exception(msg)
return self._ec2_error_response("AuthFailure", msg)
# Authenticated!
req.headers['X-Auth-Token'] = token_id
return self._application
def filter_factory(global_conf, **local_conf):
"""Return a WSGI filter app for use with paste.deploy."""
conf = global_conf.copy()
conf.update(local_conf)
def auth_filter(app):
return EC2Token(app, conf)
return auth_filter
def app_factory(global_conf, **local_conf):
conf = global_conf.copy()
conf.update(local_conf)
return EC2Token(None, conf)