cipherutil.java

基于Eclipse RCP开发的管理工具

 /*  
  * Copyright 2006 Marcel Schoffelmeer 
  * 
  * 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.s10r.crypto;

import java.security.GeneralSecurityException;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.PBEParameterSpec;

import com.s10r.util.S10RException;

public class CipherUtil
{
    // private static final String SECRET_KEY_ALGORITHM = "PBEWithMD5AndDES";
    private static final String SECRET_KEY_ALGORITHM = "PBEWithSHA1AndDESede";

    private static final byte[] SALT =
    {
            (byte) 0xc7, (byte) 0x73, (byte) 0x21, (byte) 0x8c, (byte) 0x7e,
            (byte) 0xc8, (byte) 0xee, (byte) 0x99
    };

    public static Cipher createCipher(int operationMode, String password)
    {
        try
        {
            PBEKeySpec pbeKeySpec = new PBEKeySpec(password.toCharArray());
            SecretKeyFactory keyFactory = SecretKeyFactory
                    .getInstance(SECRET_KEY_ALGORITHM);
            SecretKey pbeKey = keyFactory.generateSecret(pbeKeySpec);

            int iterationCount = 20;

            PBEParameterSpec pbeParamSpec = new PBEParameterSpec(SALT,
                    iterationCount);

            Cipher pbeCipher = Cipher.getInstance(SECRET_KEY_ALGORITHM);
            
            pbeCipher.init(operationMode, pbeKey, pbeParamSpec);
            
            return pbeCipher;
        }
        catch (GeneralSecurityException e)
        {
            throw new S10RException(e);
        }
    }
}