维帝博客 - Java + JavaScript 实现前后端AES加密解密传输

JavaScript的加密和解密用的是google的CryptoJS库。本文以AES/ECB/NoPadding为例展示AES加密和解密的方法。

需要下载CryptoJS库，下载地址如下：
[https://github.com/sytelus/CryptoJS](https://github.com/sytelus/CryptoJS "https://github.com/sytelus/CryptoJS")

需要引入库文件：

```javascript
<script src="./CryptoJS-master/rollups/aes.js"></script>
<script src="./CryptoJS-master/components/mode-ecb.js"></script>
<script src="./CryptoJS-master/components/pad-nopadding.js"></script>
```

前端代码
```javascript
const key = CryptoJS.enc.Utf8.parse("1234567890ABCDEF"); //十六位十六进制数作为秘钥
const iv = CryptoJS.enc.Utf8.parse('ABCDEF1234567890'); //十六位十六进制数作为秘钥偏移量
//解密方法
function Decrypt(word) {
    let encryptedHexStr = CryptoJS.enc.Hex.parse(word);
    let srcs = CryptoJS.enc.Base64.stringify(encryptedHexStr);
    let decrypt = CryptoJS.AES.decrypt(srcs, key, {
        iv: iv,
        mode: CryptoJS.mode.CBC,
        padding: CryptoJS.pad.Pkcs7
    });
    let decryptedStr = decrypt.toString(CryptoJS.enc.Utf8);
    return decryptedStr.toString();
}
//加密方法
function Encrypt(word) {
    let srcs = CryptoJS.enc.Utf8.parse(word);
    let encrypted = CryptoJS.AES.encrypt(srcs, key, {
        iv: iv,
        mode: CryptoJS.mode.CBC,
        padding: CryptoJS.pad.Pkcs7
    });
    return encrypted.ciphertext.toString().toUpperCase();
}
```

Java端加解密代码
```java
package com.example.demo.utils;

import javax.crypto.*;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.io.UnsupportedEncodingException;
import java.nio.charset.Charset;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;

/**
 * Aes加解密工具类
 * @author Veddy
 * @date 2021/4/20 9:56
 */
public class AesUtils {

private static String iv = "ABCDEF1234567890";//偏移量字符串必须是16位 当模式是CBC的时候必须设置偏移量
    private static String Algorithm = "AES";
    private static String AlgorithmProvider = "AES/CBC/PKCS5Padding"; //算法/模式/补码方式

public static byte[] generatorKey() throws NoSuchAlgorithmException {
        KeyGenerator keyGenerator = KeyGenerator.getInstance(Algorithm);
        keyGenerator.init(256);//默认128，获得无政策权限后可为192或256
        SecretKey secretKey = keyGenerator.generateKey();
        return secretKey.getEncoded();
    }

public static IvParameterSpec getIv() throws UnsupportedEncodingException {
        IvParameterSpec ivParameterSpec = new IvParameterSpec(iv.getBytes("utf-8"));
        System.out.println("偏移量："+byteToHexString(ivParameterSpec.getIV()));
        return ivParameterSpec;
    }

public static byte[] encrypt(String src, byte[] key) throws NoSuchAlgorithmException, NoSuchPaddingException,
            InvalidKeyException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException, InvalidAlgorithmParameterException {
        SecretKey secretKey = new SecretKeySpec(key, Algorithm);
        IvParameterSpec ivParameterSpec = getIv();
        Cipher cipher = Cipher.getInstance(AlgorithmProvider);
        cipher.init(Cipher.ENCRYPT_MODE, secretKey, ivParameterSpec);
        byte[] cipherBytes = cipher.doFinal(src.getBytes(Charset.forName("utf-8")));
        return cipherBytes;
    }

public static byte[] decrypt(String src, byte[] key) throws Exception {
        SecretKey secretKey = new SecretKeySpec(key, Algorithm);

IvParameterSpec ivParameterSpec = getIv();
        Cipher cipher = Cipher.getInstance(AlgorithmProvider);
        cipher.init(Cipher.DECRYPT_MODE, secretKey, ivParameterSpec);
        byte[] hexBytes = hexStringToBytes(src);
        byte[] plainBytes = cipher.doFinal(hexBytes);
        return plainBytes;
    }

/**
     * 将byte转换为16进制字符串
     * @param src
     * @return
     */
    public static String byteToHexString(byte[] src) {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < src.length; i++) {
            int v = src[i] & 0xff;
            String hv = Integer.toHexString(v);
            if (hv.length() < 2) {
                sb.append("0");
            }
            sb.append(hv);
        }
        return sb.toString();
    }

/**
     * 将16进制字符串装换为byte数组
     * @param hexString
     * @return
     */
    public static byte[] hexStringToBytes(String hexString) {
        hexString = hexString.toUpperCase();
        int length = hexString.length() / 2;
        char[] hexChars = hexString.toCharArray();
        byte[] b = new byte[length];
        for (int i = 0; i < length; i++) {
            int pos = i * 2;
            b[i] = (byte) (charToByte(hexChars[pos]) << 4 | charToByte(hexChars[pos + 1]));
        }
        return b;
    }

private static byte charToByte(char c) {
        return (byte) "0123456789ABCDEF".indexOf(c);
    }

public static void main(String[] args) {
        try {
            //    byte key[] = generatorKey();
            // 密钥必须是16的倍数
            byte key[] = "1234567890ABCDEF".getBytes("utf-8");
            String enc="DA09DF0D9338F76C1F71E68813673F05";
            System.out.println("解密："+new String(decrypt(enc, key), "utf-8"));
        }  catch (Exception e) {
            e.printStackTrace();
        }
    }
    public static String EncryPtion(String data){
        try {
            byte key[] = "1234567890ABCDEF".getBytes("utf-8");
            String enc = byteToHexString(encrypt(data, key));
            return enc;
        } catch (Exception e) {

e.printStackTrace();
            return "";
        }
    }

//解密
    public static String DesPtion(String data){
        try {
            byte key[] = "1234567890ABCDEF".getBytes("utf-8");
            String enc =new String(decrypt(data, key), "utf-8");
            return enc;
        } catch (Exception e) {

e.printStackTrace();
            return "9999";
        }
    }

}
```