AES-256-CTR encryption in node JS and decryption in Java

Question

I am trying to code in nodejs and decrypt for the same in nodejs works well. But when I try to do decryption in Java using the same IV and secret, it does not behave as expected.

Here is the code snippet:

Encryption in nodeJs:

var crypto = require('crypto'),
algorithm = 'aes-256-ctr',
_ = require('lodash');

var secret = 'd6F3231q7d19428743234@123nab@234';

function encrypt(text, secret) {
    var iv = crypto.randomBytes(16);
    console.log(iv);
    var cipher = crypto.createCipheriv(algorithm, new Buffer(secret), iv);
    var encrypted = cipher.update(text);

    encrypted = Buffer.concat([encrypted, cipher.final()]);

    return iv.toString('hex') + ':' + encrypted.toString('hex');
}
var encrypted = encrypt("8123497494", secret);
console.log(encrypted);

And the result:

<Buffer 94 fa a4 f4 a1 3c bf f6 d7 90 18 3f 3b db 3f b9>
94faa4f4a13cbff6d790183f3bdb3fb9:fae8b07a135e084eb91e

JAVA decryption code snippet:

public class Test {

    public static void main(String[] args) throws Exception {
        String s = "94faa4f4a13cbff6d790183f3bdb3fb9:fae8b07a135e084eb91e";
        String seed = "d6F3231q7d19428743234@123nab@234";

        decrypt(s, seed);
    }

    private static void decrypt(String s, String seed)
            throws NoSuchAlgorithmException, NoSuchPaddingException, UnsupportedEncodingException, InvalidKeyException,
            InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException {
        String parts[] = s.split(":");
        String ivString = parts[0];
        String encodedString = parts[1];
        Cipher cipher = Cipher.getInstance("AES/CTR/NoPadding");

        byte[] secretBytes = seed.getBytes("UTF-8");

        IvParameterSpec ivSpec = new IvParameterSpec(hexStringToByteArray(ivString));

        /*Removed after the accepted answer
        MessageDigest md = MessageDigest.getInstance("MD5");
        byte[] thedigest = md.digest(secretBytes);*/ 

        SecretKeySpec skey = new SecretKeySpec(thedigest, "AES");

        cipher.init(Cipher.DECRYPT_MODE, skey, ivSpec);
        byte[] output = cipher.doFinal(hexStringToByteArray(encodedString));

        System.out.println(new String(output));
    }
}

Output: s˸8ƍ

I get some unwanted value in the answer. Tried a lot of options, but none of them seem to work. Any guidance / help is appreciated.

Answer 1

JS- 32- d6F3231q7d19428743234@123nab@234 AES, ASCII .

Java MD5, MD5- AES. , .

, , , , :

• 32 ( ASCII) ;
• (KDF), AES.

, , , 256 entropy (, , ), KDF, , .

Answer 2

Java MD5 secret, :

MessageDigest md = MessageDigest.getInstance("MD5");
byte[] thedigest = md.digest(secretBytes);
SecretKeySpec skey = new SecretKeySpec(thedigest, "AES");

NodeJS . , .

, . .