package com.util;

import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import java.security.Security;
/**
 * @author xiaozhi
 * @ClassName: com.util
 * @Description:
 * @Date 2015/12/17 14:37
 * @History: <author>
 * <time>
 * <desc>
 */

public class ThreeDesUtil {
    public static final String IPScertificate  = "GPhKt7sh4dxQQZZkINGFtefRKNPyAj8S00cgAwtRyy0ufD7alNC28xCBKpa6IU7u54zzWSAv4PqUDKMgpOnM7fucO1wuwMi4RgPAnietmqYIhHXZ3TqTGKNzkxA55qYH";
    public static final String DESKEY  = "ICHuQplJ0YR9l7XeVNKi6FMn";
    public static final String DESVector = "2EDxsEfp";
    /*字符串 DESede(3DES) 加密
     * ECB模式/使用PKCS7方式填充不足位,目前给的密钥是192位
     * 3DES（即Triple DES）是DES向AES过渡的加密算法（1999年，NIST将3-DES指定为过渡的
     * 加密标准），是DES的一个更安全的变形。它以DES为基本模块，通过组合分组方法设计出分组加
     * 密算法，其具体实现如下：设Ek()和Dk()代表DES算法的加密和解密过程，K代表DES算法使用的
     * 密钥，P代表明文，C代表密表，这样，
     * 3DES加密过程为：C=Ek3(Dk2(Ek1(P)))
     * 3DES解密过程为：P=Dk1((EK2(Dk3(C)))
     * */


        /**
         * @param args在java中调用sun公司提供的3DES加密解密算法时，需要使
         * 用到$JAVA_HOME/jre/lib/目录下如下的4个jar包：
         *jce.jar
         *security/US_export_policy.jar
         *security/local_policy.jar
         *ext/sunjce_provider.jar
         */

        private static final String Algorithm = "DESede"; //定义加密算法,可用 DES,DESede,Blowfish
        //keybyte为加密密钥，长度为24字节
        //src为被加密的数据缓冲区（源）
        public static byte[] encryptMode(byte[] keybyte,byte[] src){
            try {
                //生成密钥
                SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);
                //加密
                Cipher c1 = Cipher.getInstance(Algorithm);
                c1.init(Cipher.ENCRYPT_MODE, deskey);
                return c1.doFinal(src);//在单一方面的加密或解密
            } catch (java.security.NoSuchAlgorithmException e1) {
                // TODO: handle exception
                e1.printStackTrace();
            }catch(javax.crypto.NoSuchPaddingException e2){
                e2.printStackTrace();
            }catch(java.lang.Exception e3){
                e3.printStackTrace();
            }
            return null;
        }

        //keybyte为加密密钥，长度为24字节
        //src为加密后的缓冲区
        public static byte[] decryptMode(byte[] keybyte,byte[] src){
            try {
                //生成密钥
                SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);
                //解密
                Cipher c1 = Cipher.getInstance(Algorithm);
                c1.init(Cipher.DECRYPT_MODE, deskey);
                return c1.doFinal(src);
            } catch (java.security.NoSuchAlgorithmException e1) {
                // TODO: handle exception
                e1.printStackTrace();
            }catch(javax.crypto.NoSuchPaddingException e2){
                e2.printStackTrace();
            }catch(java.lang.Exception e3){
                e3.printStackTrace();
            }
            return null;
        }

        //转换成十六进制字符串
        public static String byte2Hex(byte[] b){
            String hs="";
            String stmp="";
            for(int n=0; n<b.length; n++){
                stmp = (java.lang.Integer.toHexString(b[n]& 0XFF));
                if(stmp.length()==1){
                    hs = hs + "0" + stmp;
                }else{
                    hs = hs + stmp;
                }
                if(n<b.length-1)hs=hs+":";
            }
            return hs.toUpperCase();
        }
        public static void main(String[] args) {
            // TODO Auto-generated method stub
            //添加新安全算法,如果用JCE就要把它添加进去
            Security.addProvider(new com.sun.crypto.provider.SunJCE());
            final byte[] keyBytes = {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
            };	//24字节的密钥
            String szSrc = "This is a 3DES test. 测试";
            System.out.println("加密前的字符串:" + szSrc);
            byte[] encoded = encryptMode(keyBytes,szSrc.getBytes());
            System.out.println("加密后的字符串:" + new String(encoded));

            byte[] srcBytes = decryptMode(keyBytes,encoded);
            System.out.println("解密后的字符串:" + (new String(srcBytes)));
        }



}
