DES 加密解密算法 java 版

前言：

工作需求：所有参数（数据库连接，服务器连接，都不能使用明文传参），所以需要一个加密解密算法，本来是想写 AES 的，但是 python 环境下各种改东西调试，好烦，所以退而求其次用 DES；
DES 算法写了 java 版和 python 版，这个是 java 版，python 可以在我的博客里找一下。python版

1.直接上代码

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


public class DesEnAndDe {

    public static String DES_CBC_Encrypt(String secretKey, String str) {
        try {
            byte[] keyBytes = secretKey.getBytes();
            byte[] content = str.getBytes();
            DESKeySpec keySpec = new DESKeySpec(keyBytes);
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            SecretKey key = keyFactory.generateSecret(keySpec);

            Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
            cipher.init(Cipher.ENCRYPT_MODE, key, new IvParameterSpec(keySpec.getKey()));
            byte[] result = cipher.doFinal(content);
            return byteToHexString(result);
        } catch (Exception e) {
            System.out.println("exception:" + e.toString());
        }
        return null;
    }

    public static String DES_CBC_Decrypt(String secretKey, String str) {
        try {
            byte[] keyBytes = secretKey.getBytes();
            byte[] content = hexToByteArray(str);
            DESKeySpec keySpec = new DESKeySpec(keyBytes);
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            SecretKey key = keyFactory.generateSecret(keySpec);

            Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
            cipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(keyBytes));
            byte[] result = cipher.doFinal(content);
            return new String(result);
        } catch (Exception e) {
            System.out.println("exception:" + e.toString());
        }
        return null;
    }

    private static String byteToHexString(byte[] bytes) {
        StringBuilder sb = new StringBuilder(bytes.length);
        String sTemp;
        for (byte aByte : bytes) {
            sTemp = Integer.toHexString(0xFF & aByte);
            if (sTemp.length() < 2)
                sb.append(0);
            sb.append(sTemp.toUpperCase());
        }
        return sb.toString();
    }

    private static byte[] hexToByteArray(String inHex) {
        int hexLen = inHex.length();
        byte[] result;
        if (hexLen % 2 == 1) {
            hexLen++;
            result = new byte[(hexLen / 2)];
            inHex = "0" + inHex;
        } else {
            result = new byte[(hexLen / 2)];
        }
        int j = 0;
        for (int i = 0; i < hexLen; i += 2) {
            result[j] = (byte) Integer.parseInt(inHex.substring(i, i + 2), 16);
            j++;
        }
        return result;
    }

    public static void main(String[] o) {
        String secretKey = "wo/**bhd"; // **
        String str = "xgsqrfyw1hr38*/-ff?"; // 加密内容
        String secret_pwd = DesEnAndDe.DES_CBC_Encrypt(secretKey, str);
        System.out.println("密文：" + secret_pwd);
        String clear_pwd = DesEnAndDe.DES_CBC_Decrypt(secretKey, secret_pwd);
        System.out.println("明文：" + clear_pwd);

    }

}

2.运行主函数结果

密文：E2EEA3378DF26770E7D0BED76FAB4B2AF9F9886134706D56
明文：xgsqrfyw1hr38*/-ff?

3.tips

DES 算法要求**的位数必须是 8 的整数倍，如果不是 8 的整数倍会报错。