from __future__ import absolute_import
import base64
import hashlib
from Crypto import Random
from Crypto.Cipher import AES
class AESCipher(object):
""" Helper class for encrypting and decrypting data via AES.
Copied From: http://stackoverflow.com/a/21928790
"""
def __init__(self, key):
self.bs = 32
self.key = key
def encrypt(self, raw):
raw = self._pad(raw)
iv = Random.new().read(AES.block_size)
cipher = AES.new(self.key, AES.MODE_CBC, iv)
return base64.b64encode(iv + cipher.encrypt(raw))
def decrypt(self, enc):
enc = base64.b64decode(enc)
iv = enc[:AES.block_size]
return self._unpad(cipher.decrypt(enc[AES.block_size:])).decode('utf-8')
def _pad(self, s):
return s + (self.bs - len(s) % self.bs) * chr(self.bs - len(s) % self.bs)
@staticmethod
def _unpad(s):
return s[:-ord(s[len(s)-1:])]
