A Python Implementation of Node's createCipher Encrypt/Decrypt Function

createCipher.py

"""
  DO NOT USE THIS IN PRODUCTION! PLEASE USE createCipheriv IN NODE!
  
  OK... If you got this far you're probably like me and got stuck needing to find a way do mimic Node's createCipher.
  
  Seriously though, please don't use this...
  
  See: https://nodejs.org/docs/latest-v10.x/api/crypto.html#crypto_crypto_createcipher_algorithm_password_options
"""

from Crypto import Random
from Crypto.Cipher import AES
from hashlib import md5

BS = 16
def EVP_BytesToKey(password, salt, key_len, iv_len):
    dtot =  md5(password + salt).digest()
    d = [ dtot ]
    while len(dtot)<(iv_len+key_len):
        d.append( md5(d[-1] + password + salt).digest() )
        dtot += d[-1]
    return dtot[:key_len], dtot[key_len:key_len+iv_len]

def pad(data):
    padding = BS - len(data) % BS
    return data + padding * chr(padding)

def unpad(data):
    return data[0:-data[-1]]

def decrypt(hex_data, password):
    key,iv = EVP_BytesToKey(password, b'', 32,16)
    data = bytes.fromhex(hex_data)
    aes = AES.new(key, AES.MODE_CBC, iv)
    return unpad(aes.decrypt(data)).decode("utf-8") 

def encrypt(data, password):
    key,iv = EVP_BytesToKey(password, b'', 32,16)
    aes = AES.new(key, AES.MODE_CBC, iv)
    return aes.encrypt(pad(data)).hex()

encrypted = encrypt('This is something I want encrypted', b'password1234')
print(encrypted)
decrypted = decrypt(encrypted, b'password1234')
print(decrypted)