I've encountered a challenge trying to make existing legacy Python code encrypt/decrypt data the same way as NodeJS. Although the first 16 characters are correctly decoded, I'm facing issues with the rest of the process.
Here's the Python code snippet:
from Crypto.Cipher import AES
counter = b'HOJFKGQMRCTKUQHP'
cipher = AES.new(self.symmetric_key, AES.MODE_CTR, counter=lambda: counter)
encrypted = cipher.encrypt(data)
While researching, I came across a resource mentioning that the same counter is used in every iteration: PyCrypto problem using AES+CTR
Contrastingly, here is what works in NodeJS (ts-node) only for the first 16 characters:
import { createDecipheriv, Decipher } from 'crypto'
const decrypt = (inputBase64: string): string => {
const algorithm = 'aes-192-ctr'; // 24 byte key, 16 byte "counter"
var decipher: Decipher = createDecipheriv(algorithm, key, counter /* yes, it's an iv */)
return decipher.update(inputBase64, 'base64', 'utf8') + decipher.final('utf8');
}
Browsing through multiple sources online, I noticed that most implementations increment the counter - can the counter increment be controlled using the built-in Node crypto library? Perhaps overriding some methods could help resolve this matter. Here are examples I found which might offer clues: https://github.com/ricmoo/aes-js/blob/master/index.js#L656 https://github.com/brix/crypto-js/blob/develop/src/mode-ctr.js#L26
Is there any way I can make this work in Node environment properly without altering my legacy Python code and preserving existing data integrity?
encrypt('Testing--StackOverflow')
# outputs: 'r7G8gFNIHuY27nBjSo51nZ6mqZhVUQ=='
When attempting decryption in Node utilizing the above decrypt function:
const key = 'LKOXBRRUNBOSMENKEPPZUKWB';
const counter = 'HOJFKGQMRCTKUQHP';
const encrypted = 'r7G8gFNIHuY27nBjSo51nZ6mqZhVUQ==';
const clearText = decrypt(encrypted);
console.log('clear text:', clearText)
// outputs: clear text: Testing--StackOv�::��m
If anyone has insights or solutions to offer on this perplexing issue, I would greatly appreciate it!