Java Encryption and Javascript Decryption [closed]

I am trying to encrypt a data in java and decrypt the same in javascript. There is already a similar question in SO but it does not work for me.

My question is - Encrypted Text given by Java code is not getting decrypted by Javascript. I have hardcoded the the encrypted text and key in my JS below.

P.S. I know decryption on the UI is of no use as Key will be visible and any user can decode the code. But my requirement of doing so is to bypass a Penetration Testing tool. So please suggest how it can be done

Java code -

import java.security.Key;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
import org.apache.commons.codec.binary.Base64;

public class Crypt {
    private static final String ALGO = "AES";
    private static final byte[] keyValue = 
    new byte[] { 'A', 'b', 'c', 'd', 'e', 'f', 'g',
    'h', 'i', 'j', 'k','l', 'm', 'n', 'o', 'p'};

public static String encrypt(String Data) throws Exception {
    Key key = generateKey();
    String keyForJS = Base64.encodeBase64String(keyValue);
    System.out.println("Key2 = " + keyForJS);
    Cipher c = Cipher.getInstance(ALGO);
    c.init(Cipher.ENCRYPT_MODE, key);
    byte[] encVal = c.doFinal(Data.getBytes());
    String encryptedValue = Base64.encodeBase64(encVal).toString();
    return encryptedValue;
}

private static Key generateKey() throws Exception {
    Key key = new SecretKeySpec(keyValue, ALGO);
    return key;
}

public static void main(String a[]) throws Exception
{
  System.out.println("Encryption = " + Crypt.encrypt("Test"));

}
}

execution of the above code in eclipse generate the following output -

Key2 = [B@670b5064

Encryption = [B@3c8b22e5

Now i will use this data for my JS Code

<script src="http://crypto-js.googlecode.com/svn/tags/3.1.2/build/rollups/aes.js"></script>
<script src="http://crypto-js.googlecode.com/svn/tags/3.1.2/build/components/mode-ecb-min.js"></script>

var base64Key = "[B@670b5064"; // This is the output key from Java
var key = CryptoJS.enc.Base64.parse(base64Key);


var decryptedData = CryptoJS.AES.decrypt( "[B@3c8b22e5", key, { // This is the Output text from Java
    mode: CryptoJS.mode.ECB,
    padding: CryptoJS.pad.Pkcs7
} );
var decryptedText = decryptedData.toString( CryptoJS.enc.Utf8 );
console.log( "decryptedText = " + decryptedText );

Output of JS code -

decryptedText - (Its blank, nothing appears). Please find JS Fiddle - http://jsfiddle.net/achyut/pKNzV/11/

Maarten Bodewes

You didn't listen to the comments of GregS, so I'll do all the work for you:

HTML of Fiddle:

<script src="http://crypto-js.googlecode.com/svn/tags/3.1.2/build/rollups/aes.js"></script>
<script src="http://crypto-js.googlecode.com/svn/tags/3.1.2/build/components/mode-ecb-min.js"></script>
<body>
<pre id="output"></pre>
</body>

and the JavaScript that solves the issue, basically just the comment of GregS and an output function.

function out() {
    var args = Array.prototype.slice.call(arguments, 0);
    document.getElementById('output').innerHTML += args.join("") + "\n";
}

out("decrypted text: ");
var base64Key = "QWJjZGVmZ2hpamtsbW5vcA==";
var key = CryptoJS.enc.Base64.parse(base64Key);

var decryptedData = CryptoJS.AES.decrypt("lxbdRfoav/6UW/yZtuQM9X1qaI7qZLyuPWgmwPkti/Ayl4CpiPEAMklpaq74BU/U/MxxLgDz4CMs/jm9xzATMFyHOAvObkrnHwydC4PKsej1mqZsgYyQ4qDeKk6on/fdkkLLRMkIFYyBXRTLb/Q1Y85jzbRTOpTG50EjOxMZFlQ=", key, {
    mode: CryptoJS.mode.ECB,
    padding: CryptoJS.pad.Pkcs7
});
var decryptedText = decryptedData.toString(CryptoJS.enc.Utf8);
out("decryptedText = " + decryptedText);

You can run the fiddle here and you can find the hints with regards to the output here.

来源：https://stackoverflow.com/questions/26315885/java-encryption-and-javascript-decryption

标签

javascript

cryptography

aes

cryptojs