DES 加密

package com.huateng.ebank.framework.security;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.IvParameterSpec;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;


/**
 * DES encryption algorithm, providing the encryption and decryption
 * algorithm for byte array and string
 */

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 = "abcdefgh".getBytes();
	private final static String DES = "DES/CBC/PKCS5Padding";

	/**
	 * 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();
		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.ENCRYPT_MODE, securekey, spec);

		// Encrypting data
		retByte = cipher.doFinal(SourceData);
		return retByte;
	}

	/**
	 * 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);

		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;
	}

	public static void main(String[] args){
		if(args.length < 1){
			System.err.print("Error Using : args should contain the cmd[encryption || decryption || help || ?) 、password and key");
			System.exit(-1);
		}
		String cmd = args[0];
		if( "encryption".equalsIgnoreCase(cmd)){
			if(args.length != 3){
				System.err.print("Error Using : the method of encryption need the password and key");
				System.exit(-1);
			}
			System.out.println("-------------welcome using CryPtionData----------------");
			System.out.println("                  encryption strat                     ");
			System.out.println("password = " + args[1]);
			System.out.println("key = " + args[2]);
			CryptionData cryptionData = new CryptionData(args[2]);
			try{
				String envPwd = cryptionData.EncryptionStringData(args[1]);
				System.out.println("encry_password = " + envPwd);
			System.out.println("-------------------Success , bye!----------------------");
				System.exit(0);
			}catch(Exception ex){
				ex.printStackTrace();
			System.err.println("------------------fail , try it again!-----------------");
				System.exit(-1);
			}
		}else if( "decryption".equalsIgnoreCase(cmd)){
			if(args.length != 3){
				System.err.print("Error Using : the method of decryption need the encry_password and key");
				System.exit(-1);
			}
			System.out.println("-------------welcome using CryPtionData----------------");
			System.out.println("                   decryption strat                    ");
			System.out.println("encry_password = " + args[1]);
			System.out.println("key = " + args[2]);
			CryptionData cryptionData = new CryptionData(args[2]);
			try{
				String pwd = cryptionData.DecryptionStringData(args[1]);
				System.out.println("password = " + pwd);
				System.out.println("----------------------Success , bye!--------------------");
				System.exit(0);
			}catch(Exception ex){
				ex.printStackTrace();
		        System.err.println("----------------fail , try it again!-------------------");
				System.exit(-1);
			}
		}else if( "help".equalsIgnoreCase(cmd) || "?".equalsIgnoreCase(cmd)){
			System.out.println("-------------welcome using CryPtionData help----------------");
			System.out.println("function: encryption or decryption");
			System.out.println("eq. 'java CryptionData encryption password key' , you can get encry password!");
			System.out.println("eq. 'java CryptionData decryption encry_password  key' , you can get password!");
			System.out.println("------------------------Bye Bye!----------------------------");
		}else{
			System.err.print("Error Using : no support function, you can input 'java CryptionData help'");
			System.exit(-1);
		}

	}
}