Base64 binary import does not exist

[Patricia Andersen]

Hi guys!

I have a small issue with my code where im encrypting and decrypting messages. My import org.apache.commons.codec.binary.Base64;. does not work. It says binary does not exist_ Any idea why this happens?. Ive downloaded the codec but im starting to wonder if it has to do with where the codec folder is located, but i may be wrong. Any ideas?

import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

import org.apache.commons.codec.binary.Base64;


public class Message {

 public static void main(String[] args) throws Exception {

  //Generate Symmetric key
  KeyGenerator generator = KeyGenerator.getInstance("AES");
  generator.init(128);
  SecretKey key = generator.generateKey();
  byte[] symmetricKey =key.getEncoded();
  System.out.println("key : "+symmetricKey);
  
  //Generate private key public key pair assymmetric 
  KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
  keyPairGenerator.initialize(1024);
  KeyPair keyPair = keyPairGenerator.generateKeyPair();
  PrivateKey privateKey = keyPair.getPrivate();
  PublicKey publicKey = keyPair.getPublic();
  
  
  
  //Encrypt Data by symmetric key
  String encryptedData = encryptWithAESKey("My Secured Message", symmetricKey);
  System.out.println("Encrypted Data : " + encryptedData);
  
  //Encrypt symmetric key by public key
  Cipher cipher = Cipher.getInstance("RSA");
  cipher.init(Cipher.ENCRYPT_MODE, publicKey);
  String encryptedkey =Base64.encodeBase64String(cipher.doFinal(symmetricKey));
  
  //Send message and key to other user having private key
  
  //Decrypt symmetric Key by private key
  Cipher dipher = Cipher.getInstance("RSA");

  dipher.init(Cipher.DECRYPT_MODE, privateKey);
  byte[] decryptedSymmetricKey =dipher.doFinal(Base64.decodeBase64(encryptedkey));
  
  //Decrypt encrypted Data by decrypted symmetric key
  System.out.println("Decrypted Data : " +decryptWithAESKey(encryptedData, decryptedSymmetricKey));

 }

public static String encryptWithAESKey(String data, byte[] key) throws NoSuchAlgorithmException, NoSuchPaddingException,
   InvalidKeyException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException {
  SecretKey secKey = new SecretKeySpec(key,"AES");

  Cipher cipher = Cipher.getInstance("AES");
  
  cipher.init(Cipher.ENCRYPT_MODE, secKey);
  byte[] newData = cipher.doFinal(data.getBytes());
  
  return Base64.encodeBase64String(newData);
 }

 public static String decryptWithAESKey(String inputData, byte[] key) throws NoSuchAlgorithmException,
   NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
  Cipher cipher = Cipher.getInstance("AES");
  SecretKey secKey = new SecretKeySpec(key, "AES");

  cipher.init(Cipher.DECRYPT_MODE, secKey);
  byte[] newData = cipher.doFinal(Base64.decodeBase64(inputData.getBytes()));
  return new String(newData);

 }


}

thanks in advance

[Guillermo Ishi]

You probably just need to add it to your build path. "Properties" -> etc -> "add jar file".

[Richard Tookey]

You seem to have lifted that code from http://www.java-redefined.com/2013/08/symmetric-and-asymmetric-key-encryption.html . It is bad form to post code without providing an acknowledgement.

P.S. That code has some significant weaknesses a major one being that the private key is created on the fly so is not private to the person who is to receive the cipher text! This defeats the aim of public key cryptography.