aes.py

from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import padding
from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC
import os


def aes_encrypt(key, plaintext):
    print(key)
    #convert to 128 bit key
    iv = os.urandom(16)
    padder = padding.PKCS7(128).padder()
    padded_data = padder.update(plaintext.encode()) + padder.finalize()
    cipher = Cipher(algorithms.AES(key.encode()), modes.CBC(iv), backend=default_backend())
    encryptor = cipher.encryptor()
    cipher_text = encryptor.update(padded_data) + encryptor.finalize()
    return iv + cipher_text

def aes_decrypt(key, ciphertext):
    iv = ciphertext[:16]
    cipher_text = ciphertext[16:]
    cipher = Cipher(algorithms.AES(key.encode()), modes.CBC(iv), backend=default_backend())
    decryptor = cipher.decryptor()
    padded_data = decryptor.update(cipher_text) + decryptor.finalize()
    unpadder = padding.PKCS7(128).unpadder()
    plaintext = unpadder.update(padded_data) + unpadder.finalize()
    return plaintext.decode()