swift/test/unit/common/middleware/crypto/test_crypto_utils.py
Janie Richling 96a0e07753 Enable object body and metadata encryption
Adds encryption middlewares.

All object servers and proxy servers should be upgraded before
introducing encryption middleware.

Encryption middleware should be first introduced with the
encryption middleware disable_encryption option set to True.
Once all proxies have encryption middleware installed this
option may be set to False (the default).

Increases constraints.py:MAX_HEADER_COUNT by 4 to allow for
headers generated by encryption-related middleware.

Co-Authored-By: Tim Burke <tim.burke@gmail.com>
Co-Authored-By: Christian Cachin <cca@zurich.ibm.com>
Co-Authored-By: Mahati Chamarthy <mahati.chamarthy@gmail.com>
Co-Authored-By: Peter Chng <pchng@ca.ibm.com>
Co-Authored-By: Alistair Coles <alistair.coles@hpe.com>
Co-Authored-By: Jonathan Hinson <jlhinson@us.ibm.com>
Co-Authored-By: Hamdi Roumani <roumani@ca.ibm.com>

UpgradeImpact

Change-Id: Ie6db22697ceb1021baaa6bddcf8e41ae3acb5376
2016-06-30 23:31:15 -07:00

496 lines
22 KiB
Python

# Copyright (c) 2015-2016 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.
import os
import unittest
import mock
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from swift.common.exceptions import EncryptionException
from swift.common.middleware.crypto import crypto_utils
from swift.common.middleware.crypto.crypto_utils import (
CRYPTO_KEY_CALLBACK, Crypto, CryptoWSGIContext)
from swift.common.swob import HTTPException
from test.unit import FakeLogger
from test.unit.common.middleware.crypto.crypto_helpers import fetch_crypto_keys
class TestCryptoWsgiContext(unittest.TestCase):
def setUp(self):
class FakeFilter(object):
app = None
crypto = Crypto({})
self.fake_logger = FakeLogger()
self.crypto_context = CryptoWSGIContext(
FakeFilter(), 'object', self.fake_logger)
def test_get_keys(self):
# ok
env = {CRYPTO_KEY_CALLBACK: fetch_crypto_keys}
keys = self.crypto_context.get_keys(env)
self.assertDictEqual(fetch_crypto_keys(), keys)
# only default required keys are checked
subset_keys = {'object': fetch_crypto_keys()['object']}
env = {CRYPTO_KEY_CALLBACK: lambda: subset_keys}
keys = self.crypto_context.get_keys(env)
self.assertDictEqual(subset_keys, keys)
# only specified required keys are checked
subset_keys = {'container': fetch_crypto_keys()['container']}
env = {CRYPTO_KEY_CALLBACK: lambda: subset_keys}
keys = self.crypto_context.get_keys(env, required=['container'])
self.assertDictEqual(subset_keys, keys)
subset_keys = {'object': fetch_crypto_keys()['object'],
'container': fetch_crypto_keys()['container']}
env = {CRYPTO_KEY_CALLBACK: lambda: subset_keys}
keys = self.crypto_context.get_keys(
env, required=['object', 'container'])
self.assertDictEqual(subset_keys, keys)
def test_get_keys_missing_callback(self):
with self.assertRaises(HTTPException) as cm:
self.crypto_context.get_keys({})
self.assertIn('500 Internal Error', cm.exception.message)
self.assertIn('missing callback',
self.fake_logger.get_lines_for_level('error')[0])
self.assertIn('Unable to retrieve encryption keys.', cm.exception.body)
def test_get_keys_callback_exception(self):
def callback():
raise Exception('boom')
with self.assertRaises(HTTPException) as cm:
self.crypto_context.get_keys({CRYPTO_KEY_CALLBACK: callback})
self.assertIn('500 Internal Error', cm.exception.message)
self.assertIn('from callback: boom',
self.fake_logger.get_lines_for_level('error')[0])
self.assertIn('Unable to retrieve encryption keys.', cm.exception.body)
def test_get_keys_missing_key_for_default_required_list(self):
bad_keys = dict(fetch_crypto_keys())
bad_keys.pop('object')
with self.assertRaises(HTTPException) as cm:
self.crypto_context.get_keys(
{CRYPTO_KEY_CALLBACK: lambda: bad_keys})
self.assertIn('500 Internal Error', cm.exception.message)
self.assertIn("Missing key for 'object'",
self.fake_logger.get_lines_for_level('error')[0])
self.assertIn('Unable to retrieve encryption keys.', cm.exception.body)
def test_get_keys_missing_object_key_for_specified_required_list(self):
bad_keys = dict(fetch_crypto_keys())
bad_keys.pop('object')
with self.assertRaises(HTTPException) as cm:
self.crypto_context.get_keys(
{CRYPTO_KEY_CALLBACK: lambda: bad_keys},
required=['object', 'container'])
self.assertIn('500 Internal Error', cm.exception.message)
self.assertIn("Missing key for 'object'",
self.fake_logger.get_lines_for_level('error')[0])
self.assertIn('Unable to retrieve encryption keys.', cm.exception.body)
def test_get_keys_missing_container_key_for_specified_required_list(self):
bad_keys = dict(fetch_crypto_keys())
bad_keys.pop('container')
with self.assertRaises(HTTPException) as cm:
self.crypto_context.get_keys(
{CRYPTO_KEY_CALLBACK: lambda: bad_keys},
required=['object', 'container'])
self.assertIn('500 Internal Error', cm.exception.message)
self.assertIn("Missing key for 'container'",
self.fake_logger.get_lines_for_level('error')[0])
self.assertIn('Unable to retrieve encryption keys.', cm.exception.body)
def test_bad_object_key_for_default_required_list(self):
bad_keys = dict(fetch_crypto_keys())
bad_keys['object'] = 'the minor key'
with self.assertRaises(HTTPException) as cm:
self.crypto_context.get_keys(
{CRYPTO_KEY_CALLBACK: lambda: bad_keys})
self.assertIn('500 Internal Error', cm.exception.message)
self.assertIn("Bad key for 'object'",
self.fake_logger.get_lines_for_level('error')[0])
self.assertIn('Unable to retrieve encryption keys.', cm.exception.body)
def test_bad_container_key_for_default_required_list(self):
bad_keys = dict(fetch_crypto_keys())
bad_keys['container'] = 'the major key'
with self.assertRaises(HTTPException) as cm:
self.crypto_context.get_keys(
{CRYPTO_KEY_CALLBACK: lambda: bad_keys},
required=['object', 'container'])
self.assertIn('500 Internal Error', cm.exception.message)
self.assertIn("Bad key for 'container'",
self.fake_logger.get_lines_for_level('error')[0])
self.assertIn('Unable to retrieve encryption keys.', cm.exception.body)
def test_get_keys_not_a_dict(self):
with self.assertRaises(HTTPException) as cm:
self.crypto_context.get_keys(
{CRYPTO_KEY_CALLBACK: lambda: ['key', 'quay', 'qui']})
self.assertIn('500 Internal Error', cm.exception.message)
self.assertIn("Did not get a keys dict",
self.fake_logger.get_lines_for_level('error')[0])
self.assertIn('Unable to retrieve encryption keys.', cm.exception.body)
class TestModuleMethods(unittest.TestCase):
meta = {'iv': '0123456789abcdef', 'cipher': 'AES_CTR_256'}
serialized_meta = '%7B%22cipher%22%3A+%22AES_CTR_256%22%2C+%22' \
'iv%22%3A+%22MDEyMzQ1Njc4OWFiY2RlZg%3D%3D%22%7D'
meta_with_key = {'iv': '0123456789abcdef', 'cipher': 'AES_CTR_256',
'body_key': {'key': 'fedcba9876543210fedcba9876543210',
'iv': 'fedcba9876543210'}}
serialized_meta_with_key = '%7B%22body_key%22%3A+%7B%22iv%22%3A+%22ZmVkY' \
'2JhOTg3NjU0MzIxMA%3D%3D%22%2C+%22key%22%3A+%' \
'22ZmVkY2JhOTg3NjU0MzIxMGZlZGNiYTk4NzY1NDMyMT' \
'A%3D%22%7D%2C+%22cipher%22%3A+%22AES_CTR_256' \
'%22%2C+%22iv%22%3A+%22MDEyMzQ1Njc4OWFiY2RlZg' \
'%3D%3D%22%7D'
def test_dump_crypto_meta(self):
actual = crypto_utils.dump_crypto_meta(self.meta)
self.assertEqual(self.serialized_meta, actual)
actual = crypto_utils.dump_crypto_meta(self.meta_with_key)
self.assertEqual(self.serialized_meta_with_key, actual)
def test_load_crypto_meta(self):
actual = crypto_utils.load_crypto_meta(self.serialized_meta)
self.assertEqual(self.meta, actual)
actual = crypto_utils.load_crypto_meta(self.serialized_meta_with_key)
self.assertEqual(self.meta_with_key, actual)
def assert_raises(value, message):
with self.assertRaises(EncryptionException) as cm:
crypto_utils.load_crypto_meta(value)
self.assertIn('Bad crypto meta %r' % value, cm.exception.message)
self.assertIn(message, cm.exception.message)
assert_raises(None, 'crypto meta not a string')
assert_raises(99, 'crypto meta not a string')
assert_raises('', 'No JSON object could be decoded')
assert_raises('abc', 'No JSON object could be decoded')
assert_raises('[]', 'crypto meta not a Mapping')
assert_raises('{"iv": "abcdef"}', 'Incorrect padding')
assert_raises('{"iv": []}', 'must be string or buffer')
assert_raises('{"iv": {}}', 'must be string or buffer')
assert_raises('{"iv": 99}', 'must be string or buffer')
assert_raises('{"key": "abcdef"}', 'Incorrect padding')
assert_raises('{"key": []}', 'must be string or buffer')
assert_raises('{"key": {}}', 'must be string or buffer')
assert_raises('{"key": 99}', 'must be string or buffer')
assert_raises('{"body_key": {"iv": "abcdef"}}', 'Incorrect padding')
assert_raises('{"body_key": {"iv": []}}', 'must be string or buffer')
assert_raises('{"body_key": {"iv": {}}}', 'must be string or buffer')
assert_raises('{"body_key": {"iv": 99}}', 'must be string or buffer')
assert_raises('{"body_key": {"key": "abcdef"}}', 'Incorrect padding')
assert_raises('{"body_key": {"key": []}}', 'must be string or buffer')
assert_raises('{"body_key": {"key": {}}}', 'must be string or buffer')
assert_raises('{"body_key": {"key": 99}}', 'must be string or buffer')
def test_dump_then_load_crypto_meta(self):
actual = crypto_utils.load_crypto_meta(
crypto_utils.dump_crypto_meta(self.meta))
self.assertEqual(self.meta, actual)
actual = crypto_utils.load_crypto_meta(
crypto_utils.dump_crypto_meta(self.meta_with_key))
self.assertEqual(self.meta_with_key, actual)
def test_append_crypto_meta(self):
actual = crypto_utils.append_crypto_meta('abc', self.meta)
expected = 'abc; swift_meta=%s' % self.serialized_meta
self.assertEqual(actual, expected)
actual = crypto_utils.append_crypto_meta('abc', self.meta_with_key)
expected = 'abc; swift_meta=%s' % self.serialized_meta_with_key
self.assertEqual(actual, expected)
def test_extract_crypto_meta(self):
val, meta = crypto_utils.extract_crypto_meta(
'abc; swift_meta=%s' % self.serialized_meta)
self.assertEqual('abc', val)
self.assertDictEqual(self.meta, meta)
val, meta = crypto_utils.extract_crypto_meta(
'abc; swift_meta=%s' % self.serialized_meta_with_key)
self.assertEqual('abc', val)
self.assertDictEqual(self.meta_with_key, meta)
val, meta = crypto_utils.extract_crypto_meta('abc')
self.assertEqual('abc', val)
self.assertIsNone(meta)
# other param names will be ignored
val, meta = crypto_utils.extract_crypto_meta('abc; foo=bar')
self.assertEqual('abc', val)
self.assertIsNone(meta)
def test_append_then_extract_crypto_meta(self):
val = 'abc'
actual = crypto_utils.extract_crypto_meta(
crypto_utils.append_crypto_meta(val, self.meta))
self.assertEqual((val, self.meta), actual)
class TestCrypto(unittest.TestCase):
def setUp(self):
self.crypto = Crypto({})
def test_create_encryption_context(self):
value = 'encrypt me' * 100 # more than one cipher block
key = os.urandom(32)
iv = os.urandom(16)
ctxt = self.crypto.create_encryption_ctxt(key, iv)
expected = Cipher(
algorithms.AES(key), modes.CTR(iv),
backend=default_backend()).encryptor().update(value)
self.assertEqual(expected, ctxt.update(value))
for bad_iv in ('a little too long', 'too short'):
self.assertRaises(
ValueError, self.crypto.create_encryption_ctxt, key, bad_iv)
for bad_key in ('objKey', 'a' * 31, 'a' * 33, 'a' * 16, 'a' * 24):
self.assertRaises(
ValueError, self.crypto.create_encryption_ctxt, bad_key, iv)
def test_create_decryption_context(self):
value = 'decrypt me' * 100 # more than one cipher block
key = os.urandom(32)
iv = os.urandom(16)
ctxt = self.crypto.create_decryption_ctxt(key, iv, 0)
expected = Cipher(
algorithms.AES(key), modes.CTR(iv),
backend=default_backend()).decryptor().update(value)
self.assertEqual(expected, ctxt.update(value))
for bad_iv in ('a little too long', 'too short'):
self.assertRaises(
ValueError, self.crypto.create_decryption_ctxt, key, bad_iv, 0)
for bad_key in ('objKey', 'a' * 31, 'a' * 33, 'a' * 16, 'a' * 24):
self.assertRaises(
ValueError, self.crypto.create_decryption_ctxt, bad_key, iv, 0)
with self.assertRaises(ValueError) as cm:
self.crypto.create_decryption_ctxt(key, iv, -1)
self.assertEqual("Offset must not be negative", cm.exception.message)
def test_enc_dec_small_chunks(self):
self.enc_dec_chunks(['encrypt me', 'because I', 'am sensitive'])
def test_enc_dec_large_chunks(self):
self.enc_dec_chunks([os.urandom(65536), os.urandom(65536)])
def enc_dec_chunks(self, chunks):
key = 'objL7wjV6L79Sfs4y7dy41273l0k6Wki'
iv = self.crypto.create_iv()
enc_ctxt = self.crypto.create_encryption_ctxt(key, iv)
enc_val = [enc_ctxt.update(chunk) for chunk in chunks]
self.assertTrue(''.join(enc_val) != chunks)
dec_ctxt = self.crypto.create_decryption_ctxt(key, iv, 0)
dec_val = [dec_ctxt.update(chunk) for chunk in enc_val]
self.assertEqual(''.join(chunks), ''.join(dec_val),
'Expected value {%s} but got {%s}' %
(''.join(chunks), ''.join(dec_val)))
def test_decrypt_range(self):
chunks = ['0123456789abcdef', 'ghijklmnopqrstuv']
key = 'objL7wjV6L79Sfs4y7dy41273l0k6Wki'
iv = self.crypto.create_iv()
enc_ctxt = self.crypto.create_encryption_ctxt(key, iv)
enc_val = [enc_ctxt.update(chunk) for chunk in chunks]
self.assertTrue(''.join(enc_val) != chunks)
# Simulate a ranged GET from byte 19 to 32 : 'jklmnopqrstuv'
dec_ctxt = self.crypto.create_decryption_ctxt(key, iv, 19)
ranged_chunks = [enc_val[1][3:]]
dec_val = [dec_ctxt.update(chunk) for chunk in ranged_chunks]
self.assertEqual('jklmnopqrstuv', ''.join(dec_val),
'Expected value {%s} but got {%s}' %
('jklmnopqrstuv', ''.join(dec_val)))
def test_create_decryption_context_non_zero_offset(self):
# Verify that iv increments for each 16 bytes of offset.
# For a ranged GET we pass a non-zero offset so that the decrypter
# counter is incremented to the correct value to start decrypting at
# that offset into the object body. The counter should increment by one
# from the starting IV value for every 16 bytes offset into the object
# body, until it reaches 2^128 -1 when it should wrap to zero. We check
# that is happening by verifying a decrypted value using various
# offsets.
key = 'objL7wjV6L79Sfs4y7dy41273l0k6Wki'
def do_test():
for offset, exp_iv in mappings.items():
dec_ctxt = self.crypto.create_decryption_ctxt(key, iv, offset)
offset_in_block = offset % 16
cipher = Cipher(algorithms.AES(key),
modes.CTR(exp_iv),
backend=default_backend())
expected = cipher.decryptor().update(
'p' * offset_in_block + 'ciphertext')
actual = dec_ctxt.update('ciphertext')
expected = expected[offset % 16:]
self.assertEqual(expected, actual,
'Expected %r but got %r, iv=%s and offset=%s'
% (expected, actual, iv, offset))
iv = '0000000010000000'
mappings = {
2: '0000000010000000',
16: '0000000010000001',
19: '0000000010000001',
48: '0000000010000003',
1024: '000000001000000p',
5119: '000000001000001o'
}
do_test()
# choose max iv value and test that it wraps to zero
iv = chr(0xff) * 16
mappings = {
2: iv,
16: str(bytearray.fromhex('00' * 16)), # iv wraps to 0
19: str(bytearray.fromhex('00' * 16)),
48: str(bytearray.fromhex('00' * 15 + '02')),
1024: str(bytearray.fromhex('00' * 15 + '3f')),
5119: str(bytearray.fromhex('00' * 14 + '013E'))
}
do_test()
iv = chr(0x0) * 16
mappings = {
2: iv,
16: str(bytearray.fromhex('00' * 15 + '01')),
19: str(bytearray.fromhex('00' * 15 + '01')),
48: str(bytearray.fromhex('00' * 15 + '03')),
1024: str(bytearray.fromhex('00' * 15 + '40')),
5119: str(bytearray.fromhex('00' * 14 + '013F'))
}
do_test()
iv = chr(0x0) * 8 + chr(0xff) * 8
mappings = {
2: iv,
16: str(bytearray.fromhex('00' * 7 + '01' + '00' * 8)),
19: str(bytearray.fromhex('00' * 7 + '01' + '00' * 8)),
48: str(bytearray.fromhex('00' * 7 + '01' + '00' * 7 + '02')),
1024: str(bytearray.fromhex('00' * 7 + '01' + '00' * 7 + '3F')),
5119: str(bytearray.fromhex('00' * 7 + '01' + '00' * 6 + '013E'))
}
do_test()
def test_check_key(self):
for key in ('objKey', 'a' * 31, 'a' * 33, 'a' * 16, 'a' * 24):
with self.assertRaises(ValueError) as cm:
self.crypto.check_key(key)
self.assertEqual("Key must be length 32 bytes",
cm.exception.message)
def test_check_crypto_meta(self):
meta = {'cipher': 'AES_CTR_256'}
with self.assertRaises(EncryptionException) as cm:
self.crypto.check_crypto_meta(meta)
self.assertEqual("Bad crypto meta: Missing 'iv'",
cm.exception.message)
for bad_iv in ('a little too long', 'too short'):
meta['iv'] = bad_iv
with self.assertRaises(EncryptionException) as cm:
self.crypto.check_crypto_meta(meta)
self.assertEqual("Bad crypto meta: IV must be length 16 bytes",
cm.exception.message)
meta = {'iv': os.urandom(16)}
with self.assertRaises(EncryptionException) as cm:
self.crypto.check_crypto_meta(meta)
self.assertEqual("Bad crypto meta: Missing 'cipher'",
cm.exception.message)
meta['cipher'] = 'Mystery cipher'
with self.assertRaises(EncryptionException) as cm:
self.crypto.check_crypto_meta(meta)
self.assertEqual("Bad crypto meta: Cipher must be AES_CTR_256",
cm.exception.message)
def test_create_iv(self):
self.assertEqual(16, len(self.crypto.create_iv()))
# crude check that we get back different values on each call
self.assertNotEqual(self.crypto.create_iv(), self.crypto.create_iv())
def test_get_crypto_meta(self):
meta = self.crypto.create_crypto_meta()
self.assertIsInstance(meta, dict)
# this is deliberately brittle so that if new items are added then the
# test will need to be updated
self.assertEqual(2, len(meta))
self.assertIn('iv', meta)
self.assertEqual(16, len(meta['iv']))
self.assertIn('cipher', meta)
self.assertEqual('AES_CTR_256', meta['cipher'])
self.crypto.check_crypto_meta(meta) # sanity check
meta2 = self.crypto.create_crypto_meta()
self.assertNotEqual(meta['iv'], meta2['iv']) # crude sanity check
def test_create_random_key(self):
# crude check that we get unique keys on each call
keys = set()
for i in range(10):
key = self.crypto.create_random_key()
self.assertEqual(32, len(key))
keys.add(key)
self.assertEqual(10, len(keys))
def test_wrap_unwrap_key(self):
wrapping_key = os.urandom(32)
key_to_wrap = os.urandom(32)
iv = os.urandom(16)
with mock.patch(
'swift.common.middleware.crypto.crypto_utils.Crypto.create_iv',
return_value=iv):
wrapped = self.crypto.wrap_key(wrapping_key, key_to_wrap)
cipher = Cipher(algorithms.AES(wrapping_key), modes.CTR(iv),
backend=default_backend())
expected = {'key': cipher.encryptor().update(key_to_wrap),
'iv': iv}
self.assertEqual(expected, wrapped)
unwrapped = self.crypto.unwrap_key(wrapping_key, wrapped)
self.assertEqual(key_to_wrap, unwrapped)
def test_unwrap_bad_key(self):
# verify that ValueError is raised if unwrapped key is invalid
wrapping_key = os.urandom(32)
for length in (0, 16, 24, 31, 33):
key_to_wrap = os.urandom(length)
wrapped = self.crypto.wrap_key(wrapping_key, key_to_wrap)
with self.assertRaises(ValueError) as cm:
self.crypto.unwrap_key(wrapping_key, wrapped)
self.assertEqual(
cm.exception.message, 'Key must be length 32 bytes')
if __name__ == '__main__':
unittest.main()