AES前后端对称加密
概述
高级加密标准(AES,Advanced Encryption Standard)为最常见的对称加密算法，对称加密算法即加密和解密的过程使用同一个秘钥进行加密。本文从实用的角度去描述前后端使用AES对称加密。
需求分析
前端请求数据传递参数时，需要对其进行加密，而不是使用明文进行传输，防止http请求被人截获而获取到信息，AES对称加密就是一种方式，前端对密码进行加密，传输给后端，后端获取之后使用和前端约定好的秘钥进行解密。
前端AES加解密
前端加密需要引入crypto-js的js文件，crypto-js是加密标准的JavaScript库，实现了各种加密算法，下载地址：https://www.yuque.com/docs/share/a764ecd9-3f47-4d40-8ec6-b80aca710d38?# 《前后端加密crypto-js.js文件》
实操，demo如下
前端AES加解密代码：
// 密钥 var key = '38373134313330303030333134313738'; key = CryptoJS.enc.Hex.parse(key) var iv = CryptoJS.enc.Hex.parse("303132333435233454243444546") var src = mobile_phone; console.log('原字符串：', src); var enc = CryptoJS.AES.encrypt(src ,key,{ iv:iv, mode: CryptoJS.mode.CBC, padding: CryptoJS.pad.Pkcs7 }) console.log('加密:',enc.toString()); var enced = enc.ciphertext.toString() console.log("加密：", enced); var dec = CryptoJS.AES.decrypt(CryptoJS.format.Hex.parse(enced), key,{ iv:iv, mode: CryptoJS.mode.CBC, padding: CryptoJS.pad.Pkcs7 }) console.log('解密:',CryptoJS.enc.Utf8.stringify(dec)); 其中key和iv的值并不是随意填写的，这个是需要后端加解密生成后给到前端使用
后端AES加解密：
package unis.cloud.data.tool; import java.io.UnsupportedEncodingException; import java.nio.charset.Charset; import java.security.InvalidAlgorithmParameterException; import java.security.InvalidKeyException; import java.security.NoSuchAlgorithmException; import javax.crypto.BadPaddingException; import javax.crypto.Cipher; import javax.crypto.IllegalBlockSizeException; import javax.crypto.KeyGenerator; import javax.crypto.NoSuchPaddingException; import javax.crypto.SecretKey; import javax.crypto.spec.IvParameterSpec; import javax.crypto.spec.SecretKeySpec; public class AesTool { private static String iv = "0123456789ABCDEF";//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) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException, InvalidAlgorithmParameterException { byte key[] = "87000078".getBytes("utf-8"); 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) throws Exception { byte key[] = "87000078".getBytes("utf-8"); 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 { // 密钥必须是16的倍数 byte key[] = "8711110000222278".getBytes("utf-8"); String src = "183222222222"; System.out.println("密钥:"+byteToHexString(key)); System.out.println("原字符串:"+src); String enc = byteToHexString(encrypt(src)); System.out.println("加密："+enc); System.out.println("解密："+new String(decrypt(enc), "utf-8")); } catch (InvalidKeyException e) { e.printStackTrace(); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } catch (NoSuchPaddingException e) { e.printStackTrace(); } catch (IllegalBlockSizeException e) { e.printStackTrace(); } catch (BadPaddingException e) { e.printStackTrace(); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); } } } 后端输出结果：
密钥:38373134313330303030333134313738 原字符串:你好 偏移量：30313233343536373839414243444546 加密：08e56adf28a16558631aa0914d04bd0c 偏移量：30313233343536373839414243444546 解密：你好需要注意，后端输出的密钥和偏移量都要给前端，这样解析出来的参数才是一致的，其中后端打印出的密钥对应前端的key，后端打印出的便宜量对应前端的iv中的值！
表达可能不太清楚，调试中有问题可私信我！