def _test_encrypt_decrypt(self, size_of_data):
# max blob size is 2*2**20 -1 ( -1 due to required padding in the end )
blob = MocBlob()
blob_num = 0
key = os.urandom(AES_BLOCK_SIZE_BYTES)
iv = os.urandom(AES_BLOCK_SIZE_BYTES)
maker = CryptBlob.CryptStreamBlobMaker(key, iv, blob_num, blob)
write_size = size_of_data
string_to_encrypt = random_string(size_of_data).encode()
# encrypt string
done, num_bytes = maker.write(string_to_encrypt)
yield maker.close()
self.assertEqual(size_of_data, num_bytes)
expected_encrypted_blob_size = int(
(size_of_data / AES_BLOCK_SIZE_BYTES) + 1) * AES_BLOCK_SIZE_BYTES
self.assertEqual(expected_encrypted_blob_size, len(blob.data))
if size_of_data < MAX_BLOB_SIZE - 1:
self.assertFalse(done)
else:
self.assertTrue(done)
self.data_buf = b''
def write_func(data):
self.data_buf += data
# decrypt string
decryptor = CryptBlob.StreamBlobDecryptor(blob, key, iv, size_of_data)
yield decryptor.decrypt(write_func)
self.assertEqual(self.data_buf, string_to_encrypt)
def _test_encrypt_decrypt(self, size_of_data):
# max blob size is 2*2**20 -1 ( -1 due to required padding in the end )
blob = MocBlob()
blob_num = 0
key = Random.new().read(AES.block_size)
iv = Random.new().read(AES.block_size)
maker = CryptBlob.CryptStreamBlobMaker(key, iv, blob_num, blob)
write_size = size_of_data
string_to_encrypt = random_string(size_of_data)
# encrypt string
done, num_bytes = maker.write(string_to_encrypt)
yield maker.close()
self.assertEqual(size_of_data, num_bytes)
expected_encrypted_blob_size = (
(size_of_data / AES.block_size) + 1) * AES.block_size
self.assertEqual(expected_encrypted_blob_size, len(blob.data))
if size_of_data < conf.settings['BLOB_SIZE'] - 1:
self.assertFalse(done)
else:
self.assertTrue(done)
self.data_buf = ''
def write_func(data):
self.data_buf += data
# decrypt string
decryptor = CryptBlob.StreamBlobDecryptor(blob, key, iv, size_of_data)
decryptor.decrypt(write_func)
self.assertEqual(self.data_buf, string_to_encrypt)
def encrypt_blob(filename, key, iv):
blob = Blob()
blob_maker = CryptBlob.CryptStreamBlobMaker(binascii.unhexlify(key),
binascii.unhexlify(iv), 0,
blob)
with open(filename) as fin:
blob_maker.write(fin.read())
blob_maker.close()
def decrypt_blob(blob_file, key, iv, output):
filename = os.path.abspath(blob_file)
length = os.path.getsize(filename)
directory, blob_hash = os.path.split(filename)
blob = HashBlob.BlobFile(directory, blob_hash, True, length)
decryptor = CryptBlob.StreamBlobDecryptor(blob, binascii.unhexlify(key),
binascii.unhexlify(iv), length)
with open(output, 'w') as f:
yield decryptor.decrypt(f.write)