别以为随便写个密匙的key值就可以进行加解密了

我们都知道在使用加密解密的时候都需要密匙，但是密匙随便定义个可以吗，今天我就遇到这个坑，加密解密用的都是同一个密匙，在本地测试一切正常，然而部署到服务器的时候就亮了，解密的时候报了下面的错误，经查阅资料，原来是因为windows跟Linux的系统不同导致的，随便定义的密匙串是不行的

javax.crypto.BadPaddingException: Given final block not properly padded. Such issues can arise if a bad key is used during decryption.
	at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:991)
	at com.sun.crypto.provider.CipherCore.doFinal(CipherCore.java:847)
	at com.sun.crypto.provider.AESCipher.engineDoFinal(AESCipher.java:446)
	at javax.crypto.Cipher.doFinal(Cipher.java:2164)
	at com.ccb.operation.common.utils.AESUtil.decrypt(AESUtil.java:72)
	at com.ccb.mall.module.client.details.ation.ExceldetailAction.executeEx(ExceldetailAction.java:193)

那么该如何生成的通用的密匙串呢，下面提供一个工具类

//生成密匙的方法
public static String getSecretKey() {
    String keyStr = null;
    try {
        KeyGenerator keyGenerator = KeyGenerator.getInstance("AES");
        keyGenerator.init(128);
        SecretKey secretKey = keyGenerator.generateKey();
        byte[] keyBytes = secretKey.getEncoded();
        Key key = new SecretKeySpec(keyBytes, "AES");
        keyStr = Base64.getEncoder().encodeToString(key.getEncoded());
    } catch (Exception var5) {
        var5.printStackTrace();
    }
    return keyStr;
}

执行的结果如下，比如说生成这个GYBh3Rmey7nNzR/NpV0vAw==，就可以把这个密匙串当做常量，加密解密都用这个密匙串就可以了

加密方法：

public static String encode(String key, String text) {
    String result = null;
    try {
        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
        cipher.init(1, new SecretKeySpec(Base64.getDecoder().decode(key), "AES"));
        byte[] encodeResult = cipher.doFinal(text.getBytes());
        result = Hex.encodeHexString(encodeResult);
    } catch (Exception var5) {
        var5.printStackTrace();
    }
    return result;
}

解密方法：

public static String decode(String key, String text) {
    String result = null;
    try {
        Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
        cipher.init(2, new SecretKeySpec(Base64.getDecoder().decode(key), "AES"));
        byte[] decodeResult = cipher.doFinal(Hex.decodeHex(text));
        result = new String(decodeResult);
    } catch (Exception var5) {
        var5.printStackTrace();
    }
    return result;
}

测试效果

这样无论在windows还是Linux都可以正常进行解密了

总结：密匙串不能随便写个，必须得用系统生成的串