# 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)
val, meta = crypto_utils.extract_crypto_meta(
'abc; swift_meta=%s; foo=bar' % self.serialized_meta_with_key)
self.assertEqual('abc', val)
self.assertDictEqual(self.meta_with_key, 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()