javax.crypto.BadPaddingException

[Arpit Panwar]

package Encryption;

import java.io.*;
import java.security.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.crypto.Cipher.*;
import javax.crypto.*;
import javax.crypto.spec.*;
import sun.security.pkcs.PKCS10;
 interface AESAlgorithm {

    public String encrypt(byte[] encrypted);

    public String decrpyt(byte[] encrypted);
}
public class EncMain implements AESAlgorithm {

 	HexPass h=new HexPass();
 	GenKey g=new GenKey();
    Cipher cipher;
    SecretKeySpec skeySpec1 = null;
    static String message = "qwsderfgvcbnhjmk";

    public static void main(String[] args){
        EncMain m = new EncMain();
        
        byte[] btt = message.getBytes();
        System.out.println("Encryptd string:" + m.encrypt(btt));
        System.out.println("Decryptd string:" + m.decrpyt(btt));
    }

    public String encrypt(byte[] encrypted) {
        

        try {

            cipher = Cipher.getInstance("AES/CBC/PKCS8Padding");
            skeySpec1=g.Gen();
            byte[] rawBytes = {16, 32, 64, 32, 48, 80, 96, 112, 96, 32, 48, 80, 96, 112, 64,16};
            IvParameterSpec iv = new IvParameterSpec(rawBytes);
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec1, iv);
            byte[] encrypt  = cipher.doFinal(encrypted);
            return h.asHex(encrypt);
        } catch (Exception ex) {
            return "their is an error";
        }
    }
    public String decrpyt(byte[] encrypted) {
        String ostring = null;
        try {
            //SecretKeySpec skeySpec = null;
            skeySpec1 =g.Gen();
            byte[] rawBytes = {16, 32, 64, 32, 48, 80, 96, 112, 96, 32, 48, 80, 96, 112, 64,16};
            IvParameterSpec iv = new IvParameterSpec(rawBytes);
            System.out.println(iv);
            cipher.init(Cipher.DECRYPT_MODE, skeySpec1, iv);
            byte[] original = cipher.doFinal(encrypted);
            ostring = new String(original);
            return ostring;
        }  catch (IllegalBlockSizeException ex) {
            ex.printStackTrace();
            return "error1";
        } catch (Exception e) {
            e.printStackTrace();
            return "errro2";
        }
        
    }
}    

i keep getting badpading exception.
can anyone help me out on how to pad the message bits.

[Ulf Dittmer]

This exception usually happens when encrypted data, or an encryption key, is treated like character data (in other words, as a string). Here's a full example of AES encryption/decryption: http://java.sun.com/developer/technicalArticles/Security/AES/AES_v1.html