DES与3DES加解密

一、DES和3DES的概念

二、需求背景

       我们在线上经常使用DES加密用户id，以下简称（encodeId），后端传个前端，前端会使用localStorage保存encodeId，然后调用接口时将encodeId作为入参，后端通过encodeId区分每个用户，返回前端相应数据，但是DES加密有被破解的报道，现在使用3DES对用户id，省份证号等敏感信息进行加解密，暂时没有被攻破的记录，3DES比DES更安全。对于常用的DES和3DES线上封装一般都是下面这样。（仅供参考）

三、DES和3DES工具类

1、DESUtils 

所使用的jar包都是JDK8自带的，不需要其它依赖。

package com.cn.dl.utils;

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

public class DESUtils {

    //秘钥
    private static final String KEY = "~@#$y1a2n.&@+n@$%*(1)";
    //加密算法
    private static final String  ALGORITHM = "DES";
    //编码
    private static final String CHARSET = "UTF-8";

    /**
     * byte数组转换成十六进制字符串
     * @param bytes byte数组
     * @return
     */
    private static String bytesToHexStr(byte[] bytes) {
        String tmp = "";
        StringBuilder sb = new StringBuilder("");
        for (int i = 0; i < bytes.length; i++) {
            tmp = Integer.toHexString(bytes[i] & 0xFF);
            sb.append((tmp.length() == 1) ? "0" + tmp : tmp);
        }
        return sb.toString().toUpperCase().trim();
    }
    /**
     * 十六进制字符串转成byte数组
     * @param hexStr   十六进制字符串
     * @return
     * */
    private static byte[] hexStrToBytes(String hexStr) {
        byte[] bytes = new byte[hexStr.length() / 2];
        for (int i = 0; i < bytes.length; i++) {
            bytes[i] = (byte) Integer.parseInt(hexStr.substring(2 * i, 2 * i + 2), 16);
        }
        return bytes;
    }
    /**
     * @param key   秘钥
     * @param encodeStr  需要加密的字符串
     * @return
     */
    public static String encodeDES(String key, String encodeStr) throws Exception {
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        SecretKey secretKey = SecretKeyFactory.getInstance(ALGORITHM).generateSecret(new DESKeySpec(key.getBytes()));
        cipher.init(Cipher.ENCRYPT_MODE, secretKey);
        byte[] encrypted = cipher.doFinal(encodeStr.getBytes(CHARSET));
        return bytesToHexStr(encrypted);
    }

    /**
     * @param key          秘钥
     * @param decodeStr   需要解密的字符串
     * @return
     */
    public static String decodeDES(String key, String decodeStr) throws Exception {
        Cipher cipher = Cipher.getInstance(ALGORITHM);
        SecretKey secretKey = SecretKeyFactory.getInstance(ALGORITHM).generateSecret(new DESKeySpec(key.getBytes()));
        cipher.init(Cipher.DECRYPT_MODE, secretKey);
        byte[] decodedString = cipher.doFinal(hexStrToBytes(decodeStr));
        return new String(decodedString, CHARSET);
    }


    public static void main(String[] args) throws Exception {
        String userId = "13240115";
        String encode = DESUtils.encodeDES(KEY, userId);
        String decode = DESUtils.decodeDES(KEY, encode);
        System.out.println("用户id>>>"+userId);
        System.out.println("用户id加密>>>"+encode);
        System.out.println("用户id解密>>>"+decode);
    }
}

测试结果：

用户id>>>13240115
用户id加密>>>62BBE8100F9C6E5E6438C40FCC3B03DA
用户id解密>>>13240115

2、DESedeUtil

需要引入jar包

     commons-codec
     commons-codec
     1.11

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.digest.DigestUtils;

import java.io.UnsupportedEncodingException;


/**
 * 3DES加密算法，主要用于加密用户id，身份证号等敏感信息,防止破解
 * Created by yanshao on 2018/12/10.
 */
public class DESedeUtil {

    //秘钥
    private static final String  KEY = "~@#$y1a2n.&@+n@$%*(1)";
    //秘钥长度
    private static final int secretKeyLength = 24;
    //加密算法
    private static final String  ALGORITHM = "DESede";
    //编码
    private static final String CHARSET = "UTF-8";

    /**
     * 转换成十六进制字符串
     * @param key
     * @return
     */
    public static byte[] getHex(String key){
        byte[] secretKeyByte = new byte[24];
        try {
            byte[] hexByte;
            hexByte = new String(DigestUtils.md5Hex(key)).getBytes(CHARSET);
            //秘钥长度固定为24位
            System.arraycopy(hexByte,0,secretKeyByte,0,secretKeyLength);
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return secretKeyByte;
    }

    /**
     * 生成密钥，返回加密串
     * @param key 密钥
     * @param encodeStr 将加密的字符串
     * @return
     */
    public static String  encode3DES(String key,String encodeStr){
        try {
            Cipher cipher = Cipher.getInstance(ALGORITHM);
            cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(getHex(key), ALGORITHM));
            return Base64.encodeBase64String(cipher.doFinal(encodeStr.getBytes(CHARSET)));
        }catch(Exception e){
            e.printStackTrace();
        }
        return null;
    }
    /**
     * 生成密钥,解密，并返回字符串
     * @param key 密钥
     * @param decodeStr 需要解密的字符串
     * @return
     */
    public static String decode3DES(String key, String decodeStr){
        try {
            Cipher cipher = Cipher.getInstance(ALGORITHM);
            cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(getHex(key),ALGORITHM));
            return new String(cipher.doFinal(new Base64().decode(decodeStr)),CHARSET);
        } catch(Exception e){
            e.printStackTrace();
        }
        return null;
    }


    public static void main(String[] args) {
        String userId = "13240115";
        String encode = DESedeUtil.encode3DES(KEY, userId);
        String decode = DESedeUtil.decode3DES(KEY, encode);
        System.out.println("用户id>>>"+userId);
        System.out.println("用户id加密>>>"+encode);
        System.out.println("用户id解密>>>"+decode);
    }

}

测试结果：

用户id>>>13240115
用户id加密>>>bv6ZVR6KAunqORpY1fpOwQ==
用户id解密>>>13240115