package militeryapp;
import javax.crypto.*;
import java.security.*;
/**
* Performs encryption and decryption DES algorithm
* Last Edit: 31/05/05
* @author Wong Yat Seng
* @version 1.0
*/
public class AES{
/** Stores a generated DES key */
private Key key;
/**
* Gets the DES Key used for the encryption
* @return DES Key generated, or null if none generated
*/
public Key getKey(){
return key;
}
/**
* Performs encryption using DES algorithm
* @param data The data to be encrypted
* @return The encrypted data, or null if enryption fails
*/
public byte[] encrypt(byte[] data){
key = null;
try{
Security.addProvider(new com.sun.crypto.provider.SunJCE());
KeyGenerator kg = KeyGenerator.getInstance("AES");
Cipher cipher = Cipher.getInstance("AES");
key = kg.generateKey();
cipher.init(Cipher.ENCRYPT_MODE, key);
return (cipher.doFinal(data));
}
catch(Exception e){return null;}
}
/**
* Performs decryption using DES algorithm and a Key
* @param data The data to be decrypted
* @param key The key to be used for decryption
* @return The decrypted data, or null if decryption fails
*/
public byte[] decrypt(byte[] data, Key key){
try{
Security.addProvider(new com.sun.crypto.provider.SunJCE());
KeyGenerator kg = KeyGenerator.getInstance("AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.DECRYPT_MODE, key);
return(cipher.doFinal(data));
}
catch(Exception e){return null;}
}
}
