def encrypt(text, _key, salt=None):
"""
RETURN JSON OF ENCRYPTED DATA {"salt":s, "length":l, "data":d}
"""
from pyLibrary.queries import jx
if not isinstance(text, unicode):
Log.error("only unicode is encrypted")
if _key is None:
Log.error("Expecting a key")
if isinstance(_key, str):
_key = bytearray(_key)
if salt is None:
salt = Random.bytes(16)
data = bytearray(text.encode("utf8"))
# Initialize encryption using key and iv
key_expander_256 = key_expander.KeyExpander(256)
expanded_key = key_expander_256.expand(_key)
aes_cipher_256 = aes_cipher.AESCipher(expanded_key)
aes_cbc_256 = cbc_mode.CBCMode(aes_cipher_256, 16)
aes_cbc_256.set_iv(salt)
output = Data()
output.type = "AES256"
output.salt = convert.bytes2base64(salt)
output.length = len(data)
encrypted = bytearray()
for _, d in jx.groupby(data, size=16):
encrypted.extend(aes_cbc_256.encrypt_block(d))
output.data = convert.bytes2base64(encrypted)
json = convert.value2json(output)
if DEBUG:
test = decrypt(json, _key)
if test != text:
Log.error("problem with encryption")
return json
