DesEncrypter.java

/*
 * This file is part of DeskBin.
 *
 * Copyright (c) 2012, alta189 <http://github.com/alta189/DeskBin/>
 * DeskBin is licensed under the GNU Lesser General Public License.
 *
 * DeskBin is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * DeskBin is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package com.alta189.deskbin.util;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;

import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.KeyGenerator;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;

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

public class DesEncrypter {
	Cipher ecipher;
	Cipher dcipher;

	public DesEncrypter(SecretKey key) {
		try {
			ecipher = Cipher.getInstance("DES");
			dcipher = Cipher.getInstance("DES");
			ecipher.init(Cipher.ENCRYPT_MODE, key);
			dcipher.init(Cipher.DECRYPT_MODE, key);

		} catch (NoSuchPaddingException e) {
			e.printStackTrace();
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		} catch (InvalidKeyException e) {
			e.printStackTrace();
		}
	}

	public static SecretKey getNewKey() {
		try {
			return KeyGenerator.getInstance("DES").generateKey();
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
		return null;
	}

	public String encrypt(String str) {
		try {
			// Encode the string into bytes using utf-8
			byte[] utf8 = str.getBytes("UTF8");

			// Encrypt
			byte[] enc = ecipher.doFinal(utf8);

			// Encode bytes to base64 to get a string
			return Base64.encodeBase64String(enc);
		} catch (javax.crypto.BadPaddingException e) {
			e.printStackTrace();
		} catch (IllegalBlockSizeException e) {
			e.printStackTrace();
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		return null;
	}

	public String decrypt(String str) {
		try {
			// Decode base64 to get bytes
			byte[] dec = Base64.decodeBase64(str);

			// Decrypt
			byte[] utf8 = dcipher.doFinal(dec);

			// Decode using utf-8
			return new String(utf8, "UTF8");
		} catch (javax.crypto.BadPaddingException e) {
			e.printStackTrace();
		} catch (IllegalBlockSizeException e) {
			e.printStackTrace();
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		} catch (java.io.IOException e) {
			e.printStackTrace();
		}
		return null;
	}
}