monkey/monkey_island/cc/encryptor.py

52 lines
1.5 KiB
Python

import base64
import os
from Crypto import Random
from Crypto.Cipher import AES
__author__ = "itay.mizeretz"
class Encryptor:
_BLOCK_SIZE = 32
_DB_PASSWORD_FILENAME = "mongo_key.bin"
def __init__(self):
self._load_key()
def _init_key(self):
self._cipher_key = Random.new().read(self._BLOCK_SIZE)
with open(self._DB_PASSWORD_FILENAME, 'wb') as f:
f.write(self._cipher_key)
def _load_existing_key(self):
with open(self._DB_PASSWORD_FILENAME, 'rb') as f:
self._cipher_key = f.read()
def _load_key(self):
if os.path.exists(self._DB_PASSWORD_FILENAME):
self._load_existing_key()
else:
self._init_key()
def _pad(self, message):
return message + (self._BLOCK_SIZE - (len(message) % self._BLOCK_SIZE)) * chr(
self._BLOCK_SIZE - (len(message) % self._BLOCK_SIZE))
def _unpad(self, message):
return message[0:-ord(message[len(message) - 1])]
def enc(self, message):
cipher_iv = Random.new().read(AES.block_size)
cipher = AES.new(self._cipher_key, AES.MODE_CBC, cipher_iv)
return base64.b64encode(cipher_iv + cipher.encrypt(self._pad(message)))
def dec(self, enc_message):
enc_message = base64.b64decode(enc_message)
cipher_iv = enc_message[0:AES.block_size]
cipher = AES.new(self._cipher_key, AES.MODE_CBC, cipher_iv)
return self._unpad(cipher.decrypt(enc_message[AES.block_size:]))
encryptor = Encryptor()