Files
python-ganttclient/nova/auth/signer.py
2010-07-15 01:28:51 -04:00

128 lines
5.0 KiB
Python

# vim: tabstop=4 shiftwidth=4 softtabstop=4
# 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.
#
# PORTIONS OF THIS FILE ARE FROM:
# http://code.google.com/p/boto
# Copyright (c) 2006-2009 Mitch Garnaat http://garnaat.org/
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish, dis-
# tribute, sublicense, and/or sell copies of the Software, and to permit
# persons to whom the Software is furnished to do so, subject to the fol-
# lowing conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABIL-
# ITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
# SHALL THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
# IN THE SOFTWARE.
"""
Utility class for parsing signed AMI manifests.
"""
import logging
import hashlib
import hmac
import urllib
import base64
from nova.exception import Error
class Signer(object):
""" hacked up code from boto/connection.py """
def __init__(self, secret_key):
self.hmac = hmac.new(secret_key, digestmod=hashlib.sha1)
if hashlib.sha256:
self.hmac_256 = hmac.new(secret_key, digestmod=hashlib.sha256)
def generate(self, params, verb, server_string, path):
if params['SignatureVersion'] == '0':
return self._calc_signature_0(params)
if params['SignatureVersion'] == '1':
return self._calc_signature_1(params)
if params['SignatureVersion'] == '2':
return self._calc_signature_2(params, verb, server_string, path)
raise Error('Unknown Signature Version: %s' % self.SignatureVersion)
def _get_utf8_value(self, value):
if not isinstance(value, str) and not isinstance(value, unicode):
value = str(value)
if isinstance(value, unicode):
return value.encode('utf-8')
else:
return value
def _calc_signature_0(self, params):
s = params['Action'] + params['Timestamp']
self.hmac.update(s)
keys = params.keys()
keys.sort(cmp = lambda x, y: cmp(x.lower(), y.lower()))
pairs = []
for key in keys:
val = self._get_utf8_value(params[key])
pairs.append(key + '=' + urllib.quote(val))
return base64.b64encode(self.hmac.digest())
def _calc_signature_1(self, params):
keys = params.keys()
keys.sort(cmp = lambda x, y: cmp(x.lower(), y.lower()))
pairs = []
for key in keys:
self.hmac.update(key)
val = self._get_utf8_value(params[key])
self.hmac.update(val)
pairs.append(key + '=' + urllib.quote(val))
return base64.b64encode(self.hmac.digest())
def _calc_signature_2(self, params, verb, server_string, path):
logging.debug('using _calc_signature_2')
string_to_sign = '%s\n%s\n%s\n' % (verb, server_string, path)
if self.hmac_256:
hmac = self.hmac_256
params['SignatureMethod'] = 'HmacSHA256'
else:
hmac = self.hmac
params['SignatureMethod'] = 'HmacSHA1'
keys = params.keys()
keys.sort()
pairs = []
for key in keys:
val = self._get_utf8_value(params[key])
pairs.append(urllib.quote(key, safe='') + '=' + urllib.quote(val, safe='-_~'))
qs = '&'.join(pairs)
logging.debug('query string: %s' % qs)
string_to_sign += qs
logging.debug('string_to_sign: %s' % string_to_sign)
hmac.update(string_to_sign)
b64 = base64.b64encode(hmac.digest())
logging.debug('len(b64)=%d' % len(b64))
logging.debug('base64 encoded digest: %s' % b64)
return b64
if __name__ == '__main__':
print Signer('foo').generate({"SignatureMethod": 'HmacSHA256', 'SignatureVersion': '2'}, "get", "server", "/foo")