How to Migrate AES ECB En/Decryption from PyCrypto to Cryptography

See ya PyCrypto

My docker image cannot install PyCrypto anymore. It got an error "RuntimeError: autoconf error" and the issue said, "Don't use PyCrypto anymore."
https://github.com/pycrypto/pycrypto/issues/302

How to migrate Crypto.Cipher.AES to Cryptography

As you know, the cryptography document is sucks as well. All I found was just cryptography.hazmat.primitives.ciphers.algorithms.AES exists. No method nor example at all.

class cryptography.hazmat.primitives.ciphers.algorithms.AES(key)
https://cryptography.io/en/latest/hazmat/primitives/symmetric-encryption/

AES Encryption

I used AES.encrypt() and AES.decrypt() without any options. Later I noticed that I used AES's ECB mode. I was succeeded to migrate to cryptography without re-encrypting. Yay!

PyCrypto version

from Crypto.Cipher import AES

ENCRYPT_KEY = "9e3c8d04a37e057bb56d123456789012"

def aes_encrypt(data):
    cipher = AES.new(ENCRYPT_KEY)
    data = data + (" " * (16 - (len(data) % 16)))
    return binascii.hexlify(cipher.encrypt(data))

def aes_decrypt(data):
    cipher = AES.new(ENCRYPT_KEY)
    return cipher.decrypt(binascii.unhexlify(data)).rstrip()

Cryptography Version

from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.hazmat.backends import default_backend

ENCRYPT_KEY = "9e3c8d04a37e057bb56d123456789012"

def cipher():
    return Cipher(
        algorithms.AES(str.encode(ENCRYPT_KEY)),
        modes.ECB(),
        default_backend()
    )

def aes_encrypt(text: str) -> str:
    encryptor = cipher().encryptor()
    text = text + (" " * (16 - (len(text) % 16)))
    password_bin = encryptor.update(str.encode(text)) + encryptor.finalize()
    return binascii.hexlify(password_bin)


def aes_decrypt(text: str) -> str:
    decryptor = cipher().decryptor()
    message = decryptor.update(binascii.unhexlify(text)) + decryptor.finalize()
    return message.rstrip()

I wish this helps someone in the world.

ref

I didn't know privacyIDEA but the source code helped me a lot. Thanks!
https://github.com/privacyidea/privacyidea/blob/7199be70bbe1ebee908518a8b529ac3637a86ca1/privacyidea/lib/crypto.py#L133
https://github.com/privacyidea/privacyidea/blob/7199be70bbe1ebee908518a8b529ac3637a86ca1/privacyidea/lib/importotp.py#L86
https://www.programcreek.com/python/example/94440/cryptography.hazmat.primitives.ciphers.Cipher