java AES加密

待我称王封你为后i 2024-03-16 13:56 58阅读 0赞

#### 情形： ####

要求对数据进行AES加密

具体要求：

加密模式用： ECB（电码本模式）

填充用： pkcs7padding

密码长度： 128位

秘钥： 约定是CHINA-FUJIAN

AES在线加密地址： [在线AES加密解密 - 拉米工具][AES_ -]

![096605153caf48dfb6f4ccf2aa3d55df.png][]

因为AES是对称加密，所以得约定具体的方式。 AES具体说明看 [《AES详解》][AES]

### 代码： ###

#### AESUtils ####

import javax.crypto.Cipher;
    import javax.crypto.KeyGenerator;
    import javax.crypto.SecretKey;
    import javax.crypto.spec.SecretKeySpec;
    import java.io.UnsupportedEncodingException;
    import java.security.Key;
    import java.security.SecureRandom;
    import java.security.Security;
    import java.util.UUID;
    
    public class AESUtils {
        private static final int    KEY_BIT         = 128;
    
        private static final String TYPE            = "AES";
    
        private static final String DEFAULT_MODE    = "ECB";
    
        private static final String DEFAULT_PADDING = "PKCS7Padding";
        // private static final String DEFAULT_PADDING = "ZeroBytePadding";
    
        static
        {
            Security
                    .addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
        }
    
        private static Key getKey(String key)
        {
            byte[] keys = key.getBytes();
            byte[] keyBTmp = new byte[KEY_BIT / 8];
    
            for (int i = 0; i < keys.length && i < keyBTmp.length; i++)
            {
                keyBTmp[i] = keys[i];
            }
            return new SecretKeySpec(keyBTmp, TYPE);
        }
    
        private static String getSecurityType(String mode, String padding)
        {
            return TYPE + "/" + mode +
                    "/" + padding;
        }
    
        public static String encode(String str, String key, String mode,
                                    String padding) throws Exception
        {
            Key secretKey = getKey(key);
            Cipher cipher;
            try
            {
                cipher = Cipher.getInstance(getSecurityType(mode, padding));
                cipher.init(Cipher.ENCRYPT_MODE, secretKey);
                byte[] b = cipher.doFinal(str.getBytes());
                return byte2hex(b);
            }
            catch (Exception e)
            {
                throw new Exception("AES加密错误", e);
            }
        }
    
        public static String decode(String str, String key, String mode,
                                    String padding) throws Exception
        {
            Key secretKey = getKey(key);
            Cipher cipher;
            try
            {
                byte[] b = hex2byte(str);
                cipher = Cipher.getInstance(getSecurityType(mode, padding));
                cipher.init(Cipher.DECRYPT_MODE, secretKey);
                return new String(cipher.doFinal(b));
            }
            catch (Exception e)
            {
                throw new Exception("AES解密错误", e);
            }
        }
    
        public static String encode(String str, String key)
                throws Exception
        {
            return encode(str, key, DEFAULT_MODE, DEFAULT_PADDING);
        }
    
        public static String decode(String str, String key)
                throws Exception
        {
            return decode(str, key, DEFAULT_MODE, DEFAULT_PADDING);
        }
    
        public static String decode(String str, String key, String mode,
                                    String padding,String encodeType) throws Exception
        {
            Key secretKey = getKey(key);
            Cipher cipher;
            try
            {
                byte[] b = hex2byte(str,encodeType);
                cipher = Cipher.getInstance(getSecurityType(mode, padding));
                cipher.init(Cipher.DECRYPT_MODE, secretKey);
                return new String(cipher.doFinal(b));
            }
            catch (Exception e)
            {
                throw new Exception("AES解密错误", e);
            }
        }
    
        public static String byte2hex(byte[] src)
        {
            String tmp;
            int iLen = src.length;
            StringBuilder str = new StringBuilder(iLen * 2);
            for (byte aSrc : src) {
                tmp = (Integer.toHexString(aSrc & 0XFF));
                if (tmp.length() == 1) {
                    str.append("0");
                    str.append(tmp);
                } else {
                    str.append(tmp);
                }
            }
            return (str.toString()).toUpperCase();
        }
    
        public static byte[] hex2byte(String src)
        {
            byte[] bytes = src.getBytes();
            int iLen = bytes.length;
            byte[] arrOut = new byte[iLen / 2];
            for (int i = 0; i < iLen; i = i + 2)
            {
                String strTmp = new String(bytes, i, 2);
                arrOut[i / 2] = (byte) Integer.parseInt(strTmp, 16);
            }
            return arrOut;
        }
    
        private static byte[] hex2byte(String src, String encodeType) throws UnsupportedEncodingException
        {
            byte[] bytes = src.getBytes(encodeType);
            int iLen = bytes.length;
            byte[] arrOut = new byte[iLen / 2];
            for (int i = 0; i < iLen; i = i + 2)
            {
                String strTmp = new String(bytes, i, 2);
                arrOut[i / 2] = (byte) Integer.parseInt(strTmp, 16);
            }
            return arrOut;
        }
    
        public static void main(String[] args) throws Exception {
            // 随机生成秘钥
            String key = UUID.randomUUID().toString().replaceAll("-", "");
            // 创建秘钥生成器
            KeyGenerator keyGenerator = KeyGenerator.getInstance("AES");
            // 初始化秘钥
            keyGenerator.init(new SecureRandom(key.getBytes()));
            // 生成秘钥
            SecretKey secretKey = keyGenerator.generateKey();
            System.out.println("秘钥： " + byte2hex(secretKey.getEncoded()));
    
            String privateKey = "CHINA-FUJIAN";
            String date = "2022-04-30";
            String secretDate = AESUtils.encode(date, privateKey);
            System.out.println("加密后： " + secretDate);
            System.out.println("解密后： " + AESUtils.decode(secretDate, privateKey));
        }
    }

#### 使用: ####

@Value("${aes.key:CHINA-FUJIAN}")
        private String aesKey;
    
    
        String decodeUserName = AESUtils.decode(userName, aesKey);

### 总结： ###

使用AES对称加密，需要约定具体的内容才能保持一致。

[AES_ -]: https://tool.lmeee.com/jiami/aes
[096605153caf48dfb6f4ccf2aa3d55df.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/16/a78e5a8949a64f649e99f661ce490675.png
[AES]: https://blog.csdn.net/qq_39126560/article/details/126955368