Unity C# AES 암호화/복호화

유니티에서 C#에서 지원해주는 암호화 기능을 사용해 데이터를 숨기는 기능
로컬에 JSON 형식(string 형식)으로 데이터의 저장 시 정보를 숨기는데 적용이 가능

using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
using UnityEngine;

public class AESCrypto : MonoBehaviour
{
    // 키로 사용하기 위한 암호 정의
    private static readonly string PASSWORD = "3ds1s334e4dcc7c4yz4554e732983h";

    // 인증키 정의
    private static readonly string KEY = PASSWORD.Substring(0, 128 / 8);

    // 암호화
    public static string AESEncrypt128(string plain)
    {
        byte[] plainBytes = Encoding.UTF8.GetBytes(plain);

        RijndaelManaged myRijndael = new RijndaelManaged();
        myRijndael.Mode = CipherMode.CBC;
        myRijndael.Padding = PaddingMode.PKCS7;
        myRijndael.KeySize = 128;

        MemoryStream memoryStream = new MemoryStream();

        ICryptoTransform encryptor = myRijndael.CreateEncryptor(Encoding.UTF8.GetBytes(KEY), Encoding.UTF8.GetBytes(KEY));

        CryptoStream cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write);
        cryptoStream.Write(plainBytes, 0, plainBytes.Length);
        cryptoStream.FlushFinalBlock();

        byte[] encryptBytes = memoryStream.ToArray();

        string encryptString = Convert.ToBase64String(encryptBytes);

        cryptoStream.Close();
        memoryStream.Close();

        return encryptString;
    }

    // 복호화
    public static string AESDecrypt128(string encrypt)
    {
        byte[] encryptBytes = Convert.FromBase64String(encrypt);

        RijndaelManaged myRijndael = new RijndaelManaged();
        myRijndael.Mode = CipherMode.CBC;
        myRijndael.Padding = PaddingMode.PKCS7;
        myRijndael.KeySize = 128;

        MemoryStream memoryStream = new MemoryStream(encryptBytes);

        ICryptoTransform decryptor = myRijndael.CreateDecryptor(Encoding.UTF8.GetBytes(KEY), Encoding.UTF8.GetBytes(KEY));

        CryptoStream cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read);

        byte[] plainBytes = new byte[encryptBytes.Length];

        int plainCount = cryptoStream.Read(plainBytes, 0, plainBytes.Length);

        string plainString = Encoding.UTF8.GetString(plainBytes, 0, plainCount);

        cryptoStream.Close();
        memoryStream.Close();

        return plainString;
    }

    // 적용 예제
    void Start()
    {
        string str = "원본 문자 정보";
        Debug.Log("plain : " + str1);

        string str1 = AESEncrypt128(str1);
        Debug.Log("AES128 encrypted : " + str1);

        string str2 = AESDecrypt128(str2);
        Debug.Log("AES128 decrypted : " + str2);
    }
}