com.rdonasco.security.utils.EncryptionUtil.java Source code

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Here is the source code for com.rdonasco.security.utils.EncryptionUtil.java

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/*
 * EncryptionUtil.java
 *
 * Created on April 19, 2006, 12:18 AM
 *
 * Copyright 2004-2006 Roy Donasco Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
package com.rdonasco.security.utils;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Properties;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.PBEParameterSpec;
import org.apache.commons.codec.binary.Base64;

/**
 * This class is used for encrypting decrypting String using password.
 *
 * @author Roy F. Donasco
 */
public class EncryptionUtil {
    private static final Logger LOG = Logger.getLogger(EncryptionUtil.class.getName());

    /**
     * Creates a new instance of EncryptionUtil
     */
    public EncryptionUtil() {
    }

    // Salt
    private static final byte[] SALT = { (byte) 0xc7, (byte) 0x73, (byte) 0x21, (byte) 0x8c, (byte) 0x7e,
            (byte) 0xc8, (byte) 0xee, (byte) 0x99 };
    // Iteration count
    private static final int COUNT = 24;
    private static final PBEParameterSpec PBE_PARAM_SPEC = new PBEParameterSpec(SALT, COUNT);
    private static SecretKeyFactory keyFactory;
    //   private static final String CIPHER_TYPE = "DES/ECB/PKCS5Padding";
    private static final String CIPHER_KEY_SPEC = "PBEWithMD5AndDES";
    //   private static final String CIPHER_ALGORITHM = "DES";

    public static SecretKeyFactory getKeyFactory() throws Exception {
        if (null == keyFactory) {
            keyFactory = SecretKeyFactory.getInstance(CIPHER_KEY_SPEC);
        }
        return keyFactory;
    }

    public static String encryptWithPassword(String stringToEncrypt, String password) throws Exception {
        PBEKeySpec pbeKeySpec = new PBEKeySpec(password.toCharArray(), SALT, COUNT);
        SecretKey pbeKey = getKeyFactory().generateSecret(pbeKeySpec);
        Cipher pbeCipher = Cipher.getInstance(CIPHER_KEY_SPEC);
        pbeCipher.init(Cipher.ENCRYPT_MODE, pbeKey, PBE_PARAM_SPEC);
        byte[] encryptedBytes = pbeCipher.doFinal(stringToEncrypt.getBytes());
        return Base64.encodeBase64String(encryptedBytes);
    }

    public static String decryptWithPassword(String encryptedString, String password) throws Exception {
        PBEKeySpec pbeKeySpec = new PBEKeySpec(password.toCharArray(), SALT, COUNT);
        SecretKey pbeKey = getKeyFactory().generateSecret(pbeKeySpec);
        Cipher pbeCipher = Cipher.getInstance(CIPHER_KEY_SPEC);
        pbeCipher.init(Cipher.DECRYPT_MODE, pbeKey, PBE_PARAM_SPEC);
        byte[] decryptedBytes = pbeCipher.doFinal(Base64.decodeBase64(encryptedString));
        return new String(decryptedBytes);
    }

    public static void main(String[] args) throws Exception {
        if (0 == args.length) {
            System.out.println("usage: EncryptionUtil <propertyfile>,<output.keyfile>");
            System.exit(-1);

        }
        generateEncryptedPassword(args[0], args[1]);
    }

    private static void generateEncryptedPassword(String propsFile, String outFile) throws Exception {
        FileInputStream fis = null;
        FileOutputStream fos = null;
        try {
            fis = new FileInputStream(new File(propsFile));
            Properties props = new Properties();
            props.load(fis);
            String stringToEncrypt = props.getProperty("password");
            String passphrase = props.getProperty("passphrase");
            System.out.println("passphrase:<" + passphrase + ">");
            System.out.println("encrypting " + stringToEncrypt);
            String encrypted = EncryptionUtil.encryptWithPassword(stringToEncrypt, passphrase);
            System.out.println("encrypted:" + encrypted);
            String decrypted = EncryptionUtil.decryptWithPassword(encrypted, passphrase);
            System.out.println("decrypted:" + decrypted);
            if (!stringToEncrypt.equals(decrypted)) {
                throw new Exception(
                        "password cannot be decrypted properly, please choose another password or change passphrase.");
            }
            Properties keyProperties = new Properties();
            keyProperties.put("encrypted", encrypted);
            fos = new FileOutputStream(new File(outFile));
            keyProperties.store(fos,
                    "last updated " + new SimpleDateFormat("dd/MMM/yyyy HH:mm:ss").format(new Date()));

        } finally {
            if (null != fis) {
                try {
                    fis.close();
                } catch (IOException ex) {
                    LOG.log(Level.SEVERE, ex.getMessage(), ex);
                }
            }
            if (null != fos) {
                try {
                    fos.close();
                } catch (IOException ex) {
                    LOG.log(Level.SEVERE, ex.getMessage(), ex);
                }
            }
        }
    }
}