descbc算法java版

descbc算法java版

import javax.crypto.Cipher;  
import javax.crypto.SecretKey;  
import javax.crypto.SecretKeyFactory;  
import javax.crypto.spec.*;  
import sun.misc.*;  

/** 
 * DES encryption algorithm, providing the encryption and decryption algorithm 
 * for byte array and string 
 *  
 * @author : Yao (WICT) 
 * @version 1.0 
 */  
public class CryptionData {  
    // The length of Encryptionstring should be 8 bytes and not be  
    // a weak key  
    private String EncryptionString;  

    // The initialization vector should be 8 bytes  
    private final byte[] EncryptionIV = { 0x11, 0x22, 0x4F, 0x58, (byte) 0x88,  
            0x10, 0x40, 0x38, 0x28, 0x25, 0x79, 0x51, (byte) 0xCB, (byte) 0xDD,  
            0x55, 0x66, 0x77, 0x29, 0x74, (byte) 0x98, 0x30, 0x40, 0x36,  
            (byte) 0xE2 };  //初始化向量
    private final static String DES = "DES/CBC/PKCS5Padding";  //DES模式

    /** 
     * Saving key for encryption and decryption 
     *  
     * @param EncryptionString 
     *            String 
     */  
    public CryptionData(String EncryptionString) {  
        this.EncryptionString = EncryptionString;  
    }  

    /** 
     * Encrypt a byte array 
     *  
     * @param SourceData 
     *            byte[] 
     * @throws Exception 
     * @return byte[] 
     */  
    public byte[] EncryptionByteData(byte[] SourceData) throws Exception {  
        byte[] retByte = null;  

        // Create SecretKey object  

        byte[] EncryptionByte = EncryptionString.getBytes();//明文轉爲byte  
        DESKeySpec dks = new DESKeySpec(EncryptionByte);//聲明一個具體加密構造器的特別密鑰special key
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES"); 
//聲明瞭一個DES的密鑰工廠 
        SecretKey securekey = keyFactory.generateSecret(dks); //密鑰生成器產生真正的DES密鑰 

        // Create IvParameterSpec object with initialization vector  
        IvParameterSpec spec = new IvParameterSpec(EncryptionIV);  

        // Create Cipter object  
        Cipher cipher = Cipher.getInstance(DES);  

        // Initialize Cipher object  
        cipher.init(Cipher.ENCRYPT_MODE, securekey, spec); //初始化加密構造器 

        // Encrypting data  
        retByte = cipher.doFinal(SourceData);  //完成加密
        return retByte;  //返回加密的byte
    }  

    /** 
     * Decrypt a byte array 
     *  
     * @param SourceData 
     *            byte[] 
     * @throws Exception 
     * @return byte[] 
     */  
    public byte[] DecryptionByteData(byte[] SourceData) throws Exception {  
        byte[] retByte = null;  

        // Create SecretKey object  
        byte[] EncryptionByte = EncryptionString.getBytes();  
        DESKeySpec dks = new DESKeySpec(EncryptionByte);  
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");  
        SecretKey securekey = keyFactory.generateSecret(dks);  

        // Create IvParameterSpec object with initialization vector  
        IvParameterSpec spec = new IvParameterSpec(EncryptionIV);  

        // Create Cipter object  
        Cipher cipher = Cipher.getInstance(DES);  

        // Initialize Cipher object  
        cipher.init(Cipher.DECRYPT_MODE, securekey, spec);  

        // Decrypting data  
        retByte = cipher.doFinal(SourceData);  

        return retByte;  
    }  

    /** 
     * Encrypt a string 
     *  
     * @param SourceData 
     *            String 
     * @throws Exception 
     * @return String 
     */  
    public String EncryptionStringData(String SourceData) throws Exception {  
        String retStr = null;  
        byte[] retByte = null;  

        // Transform SourceData to byte array  
        byte[] sorData = SourceData.getBytes();  

        // Encrypte data  
        retByte = EncryptionByteData(sorData);  

        // Encode encryption data  
        BASE64Encoder be = new BASE64Encoder();  
        retStr = be.encode(retByte); //以base64編碼保存密文 

        return retStr;  
    }  

    /** 
     * Decrypt a string 
     *  
     * @param SourceData 
     *            String 
     * @throws Exception 
     * @return String 
     */  
    public String DecryptionStringData(String SourceData) throws Exception {  
        String retStr = null;  
        byte[] retByte = null;  

        // Decode encryption data  
        BASE64Decoder bd = new BASE64Decoder();  
        byte[] sorData = bd.decodeBuffer(SourceData);  

        // Decrypting data  
        retByte = DecryptionByteData(sorData);  
        retStr = new String(retByte);  

        return retStr;  
    }