How to encrypt text with a password in python?

Question

Surprisingly difficult to find a straight answer to this on Google.

I\'m wanting to collect a piece of text and a message from a user such as 1PWP7a6xgoYx81VZo

Answer 1

Here is my solution for anyone who may be interested:

from Crypto.Cipher import AES  # pip install pycrypto
import base64

def cypher_aes(secret_key, msg_text, encrypt=True):
    # an AES key must be either 16, 24, or 32 bytes long
    # in this case we make sure the key is 32 bytes long by adding padding and/or slicing if necessary
    remainder = len(secret_key) % 16
    modified_key = secret_key.ljust(len(secret_key) + (16 - remainder))[:32]
    print(modified_key)

    # input strings must be a multiple of 16 in length
    # we achieve this by adding padding if necessary
    remainder = len(msg_text) % 16
    modified_text = msg_text.ljust(len(msg_text) + (16 - remainder))
    print(modified_text)

    cipher = AES.new(modified_key, AES.MODE_ECB)  # use of ECB mode in enterprise environments is very much frowned upon

    if encrypt:
        return base64.b64encode(cipher.encrypt(modified_text)).strip()

    return cipher.decrypt(base64.b64decode(modified_text)).strip()


encrypted = cypher_aes(b'secret_AES_key_string_to_encrypt/decrypt_with', b'input_string_to_encrypt/decrypt', encrypt=True)
print(encrypted)
print()
print(cypher_aes(b'secret_AES_key_string_to_encrypt/decrypt_with', encrypted, encrypt=False))

Result:

b'secret_AES_key_string_to_encrypt'
b'input_string_to_encrypt/decrypt '
b'+IFU4e4rFWEkUlOU6sd+y8JKyyRdRbPoT/FvDBCFeuY='

b'secret_AES_key_string_to_encrypt'
b'+IFU4e4rFWEkUlOU6sd+y8JKyyRdRbPoT/FvDBCFeuY=    '
b'input_string_to_encrypt/decrypt'