Reputation: 667
I am working on the web application using react as front-end and spring mvc as back-end. I need to store some user information in local storage of the browser. I do not want to store that info in local storage as a plain text. So I thought to go for AES encryption at server side and pushing those data back to JS side. For that I need client side decryption framework. I found crypto-js as very useful for all these things. I am not able to understand where I am lacking at client side to decrypt and decode.
I am explaining my Spring Side Encryption Code first which is absolutely fine:
public class EncryptDecrypt {
private static final String SECRET_KEY_1 = "ssdkF$HUy2A#D%kd";
private static final String SECRET_KEY_2 = "weJiSEvR5yAC5ftB";
private IvParameterSpec ivParameterSpec;
private SecretKeySpec secretKeySpec;
private Cipher cipher;
public EncryptDecrypt() throws UnsupportedEncodingException, NoSuchPaddingException, NoSuchAlgorithmException {
ivParameterSpec = new IvParameterSpec(SECRET_KEY_1.getBytes("UTF-8"));
secretKeySpec = new SecretKeySpec(SECRET_KEY_2.getBytes("UTF-8"), "AES");
cipher = Cipher.getInstance("AES/CBC/PKCS5PADDING");
}
public String encrypt(String toBeEncrypt) throws NoSuchPaddingException, NoSuchAlgorithmException,
InvalidAlgorithmParameterException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, ivParameterSpec);
byte[] encrypted = cipher.doFinal(toBeEncrypt.getBytes());
return Base64.encodeBase64String(encrypted);
}
}
At the client side, I am not able to decode and decrypt the code with simple things. Here is my client side code:
var CryptoJS = require("crypto-js");
var data = "Ggydx4oA1+SKBw+unA8BUUm2tnvkQbp1terdF2PEGFYSEZL/ye08op/0b0BauGtIl1dBIodrlKXo2de3MykYmocd3ctxFtIIki01V+M8XeQj6B384o0G+H7NpVx5tCJjPDvdqVRObtxCTqu3r8QRzYTNcMM5bRhbYxCYl8/NRyPQJnmcJDlRBeVOoJiQNA7Qd5UJD/mNivoyMUfYGV7/DlpylQWWwEAHVdgcb865i8jnf3vqURehAXYoaD6Bgodi1EM4H007uv0o6NEOk3H4jQ==";
var key = "weJiSEvR5yAC5ftB";
// Decode the base64 data so we can separate iv and crypt text.
var rawData = atob(data);
var iv = "ssdkF$HUy2A#D%kd";
var crypttext = rawData.substring(16);
console.log(rawData);
// Decrypt...
var plaintextArray = CryptoJS.AES.decrypt(
{ ciphertext: CryptoJS.enc.Base64.parse(crypttext) },
key,
{ iv: iv }
);
console.log(plaintextArray);
console.log(CryptoJS.enc.Base64.stringify(plaintextArray));
var decryptedData = JSON.parse(CryptoJS.enc.Base64.stringify(plaintextArray).toString(CryptoJS.enc.Utf8));
console.log(decryptedData);
P.S: I have sent JSON to client side and so that I am parsing it in the end. I am newbie for encryption and decryption. I am really stuck with what my client side code should look a like. Please help.
Upvotes: 8
Views: 8400
Reputation: 2010
You shouldn't pass string as key in CryptoJS
. In this case it considers this string not as key, but as password. And generate key from password by using PBKDF
. Working example below:
var data = "Ggydx4oA1+SKBw+unA8BUUm2tnvkQbp1terdF2PEGFYSEZL/ye08op/0b0BauGtIl1dBIodrlKXo2de3MykYmocd3ctxFtIIki01V+M8XeQj6B384o0G+H7NpVx5tCJjPDvdqVRObtxCTqu3r8QRzYTNcMM5bRhbYxCYl8/NRyPQJnmcJDlRBeVOoJiQNA7Qd5UJD/mNivoyMUfYGV7/DlpylQWWwEAHVdgcb865i8jnf3vqURehAXYoaD6Bgodi1EM4H007uv0o6NEOk3H4jQ==";
var rawData = CryptoJS.enc.Base64.parse(data);
var key = CryptoJS.enc.Latin1.parse("weJiSEvR5yAC5ftB");
var iv = CryptoJS.enc.Latin1.parse("ssdkF$HUy2A#D%kd");
var plaintextData = CryptoJS.AES.decrypt(
{ ciphertext: rawData },
key,
{ iv: iv });
var plaintext = plaintextData.toString(CryptoJS.enc.Latin1);
console.log(plaintext);
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.9-1/crypto-js.js"></script>
BTW, you shouldn't use the same IV every time. In this case you miss the base purpose of IV and CBC mode. Your overall security becomes equal to ECB mode.
Upvotes: 6