qrcode加密範例

gistfile1.txt

using System;
using System.Text;
using System.Security.Cryptography;
using System.Web;

namespace Rextester
{
    public class Program
    {
        public static void Main(string[] args)
        {
            String mlResult = "";
            byte[] mlAesEncDataByte = null;

            byte[] mlKeyByte = HexStringToByteArray("5E8B6E1998F421204C6576544FE1A26B44FC775982D8CE2E");//加密基碼
            byte[] mlIcvByte = Encoding.GetEncoding("utf-8").GetBytes("FOCASAPIFOCASAPI");//IV值

            String mlData = "TWQRP%3A%2F%2F%E6%98%9F%E4%B9%9D%E5%AE%A2%E5%92%96%E5%95%A1%2F158%2F01%2FV1%3FD1%3D12500%26D3%3DAVnVbcN9xxRv%26D10%3D901%26D11%3D00%2C00600611122233344400000001%3B01%2C00600611122233344400000001%3B04%2C00800899887766554400000001%26D12%3D20170630130000%26OprodNumber%3D%E6%8B%BF%E9%90%B5";//UTF-8 URLEncode後的加密前電文 (以台灣Pay QR Code為例)
            byte[] mlDataByte = Encoding.GetEncoding("utf-8").GetBytes(mlData);

            //取得電文長度10進位int -> 轉換成16進位字串 -> 右靠左補0成4碼HEX字串 -> 轉換成長度為2的byte[]
            int mlDataLen = mlDataByte.Length;
            String mlDataLen16 = "0000" + Convert.ToString(mlDataLen, 16);
            byte[] mlDataLenByte = HexStringToByteArray(mlDataLen16.Substring(mlDataLen16.Length - 4, 4));

            //組合轉換後的準備加密資料
            int mlDataAllLen = mlDataLen + 2;
            byte[] mlDataAllByte = new byte[mlDataAllLen];

            //前兩位放電文長度轉換成的byte[]  mlDataLenByte
            mlDataAllByte[0] = mlDataLenByte[0];
            mlDataAllByte[1] = mlDataLenByte[1];
            //之後放mlDataByte
            for (int i = 0; i < mlDataLen; i++)
            {
                mlDataAllByte[2 + i] = mlDataByte[i];
            }

            //AES加密  Padding直接使用Zeros就好  不須手動填補
            AesCryptoServiceProvider aes = new AesCryptoServiceProvider();
            aes.IV = mlIcvByte;
            aes.Key = mlKeyByte;
            aes.Mode = CipherMode.CBC;
            aes.Padding = PaddingMode.Zeros;
            mlAesEncDataByte = aes.CreateEncryptor().TransformFinalBlock(mlDataAllByte, 0, mlDataAllByte.Length);
            if (mlAesEncDataByte != null)
            {
                //加密結果byte[]  在最前方再補一碼byte=加密基碼版本 0x02
                byte[] mlAesAllByte = new byte[mlAesEncDataByte.Length + 1];

                mlAesAllByte[0] = (byte)0x02;
                for (int k = 0; k < mlAesEncDataByte.Length; k++)
                {
                    mlAesAllByte[1 + k] = mlAesEncDataByte[k];
                }

                //Base64轉換
                mlResult = Convert.ToBase64String(mlAesAllByte);                
                
                //URLEncode
                String encQRCode = HttpUtility.UrlEncode(mlResult);
                //Console.WriteLine(encQRCode);
            }
        }
        
        public static byte[] HexStringToByteArray(String piHexString)
        {
            byte[] mlResult = null;
            StringBuilder olHexStringBuilder = new StringBuilder(piHexString);
            if (piHexString.Length % 2 == 1) //奇數位左補0
            {
                olHexStringBuilder.Insert(0, '0');
            }
            byte[] olByteArray = new byte[(piHexString.Length + 1) / 2];
            for (int idxI = 0; idxI < olByteArray.Length; idxI++)
            {
                olByteArray[idxI] = (byte)Convert.ToInt32(olHexStringBuilder.ToString(idxI * 2, 2), 16);
            }
            mlResult = olByteArray;
            return mlResult;
        }
    }
}