HYTOS

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Security.Cryptography;

using System.IO;

using Microsoft.Win32;

using System.Net.NetworkInformation;

namespace DOFTECH.License

{

    public static class License

    {

        public static bool IsEnabled()

        {

            bool result = false;

            string path = string.Empty;

            try

            {

                RegistryKey key = Registry.LocalMachine;

                RegistryKey software = key.OpenSubKey("SOFTWARE");

                RegistryKey DOFTECH = software.OpenSubKey("DOFTECH");

                RegistryKey SPPIDConverter = DOFTECH.OpenSubKey("SPPIDConverter", true);

                path = SPPIDConverter.GetValue("path") + "licenses.licx";

                if (File.Exists(path))

                {

                    string data = File.ReadAllText(path);

                    data = Crypt.decrypt(data, "dof1073#");

                    if (data.StartsWith("Date:"))

                    {

                        data = data.Remove(0, "Date:".Length);

                        if (string.IsNullOrEmpty(data))

                        {

                            if (SPPIDConverter.GetValue("Version") == null)

                            {

                                SPPIDConverter.SetValue("Version", "U");

                                data = "Date:" + DateTime.Today.ToShortDateString();

                                data = Crypt.encrypt(data, "dof1073#");

                                File.WriteAllText(path, data);

                                result = true;

                            }

                        }

                        else

                        {

                            DateTime dataTime = DateTime.MinValue;

                            DateTime currentTime = DateTime.Now;

                            if (DateTime.TryParse(data, out dataTime) && DateTime.Compare(dataTime.AddDays(14), currentTime) >= 0)

                                result = true;

                        }

                    }

                    else if (data.StartsWith("Absolute:"))

                    {

                        data = data.Remove(0, "Absolute:".Length);

                        string macAddress = NetworkInterface.GetAllNetworkInterfaces()[0].GetPhysicalAddress().ToString();

                        if (string.IsNullOrEmpty(data))

                        {

                            data = "Absolute:" + macAddress;

                            data = Crypt.encrypt(data, "dof1073#");

                            File.WriteAllText(path, data);

                            result = true;

                        }

                        else if (macAddress == data)

                            result = true;

                    }

                }

            }

            catch (Exception ex)

            {

            }

            return result;

        }

        public static string SHA256Hash(string data)

        {

            SHA256 sha = new SHA256Managed();

            byte[] hash = sha.ComputeHash(Encoding.ASCII.GetBytes(data));

            StringBuilder stringBuilder = new StringBuilder();

            foreach (byte b in hash)

            {

                stringBuilder.AppendFormat("{0:x2}", b);

            }

            return stringBuilder.ToString();

        }

        private static void CreateDateLicenseFile()

        {

            string path = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory) + @"\[Date]licenses.licx";

            string data = "Date:";

            using (StreamWriter sw = File.CreateText(path))

            {

                data = Crypt.encrypt(data, "dof1073#");

                sw.Write(data);

                sw.Close();

                sw.Dispose();

            }

        }

        private static void CreateAbsoluteLicenseFile()

        {

            string path = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory) + @"\[Absolute]licenses.licx";

            string data = "Absolute:";

            using (StreamWriter sw = File.CreateText(path))

            {

                data = Crypt.encrypt(data, "dof1073#");

                sw.Write(data);

                sw.Close();

                sw.Dispose();

            }

        }

    }

    class Crypt

    {

        public static String encrypt(String text, String password)

        {

            RijndaelManaged RijndaelCipher = new RijndaelManaged();

            byte[] plainText = Encoding.UTF8.GetBytes(text);

            byte[] salt = Encoding.UTF8.GetBytes(password);

            PasswordDeriveBytes secretKey = new PasswordDeriveBytes(password, salt);

            ICryptoTransform Encryptor = RijndaelCipher.CreateEncryptor(secretKey.GetBytes(32), secretKey.GetBytes(16));

            MemoryStream memoryStream = new MemoryStream();

            CryptoStream cryptoStream = new CryptoStream(memoryStream, Encryptor, CryptoStreamMode.Write);

            cryptoStream.Write(plainText, 0, plainText.Length);     // 암호화 시작

            cryptoStream.FlushFinalBlock();

            byte[] cryptBytes = memoryStream.ToArray();

            // 스트림을 닫습니다.

            memoryStream.Close();

            cryptoStream.Close();

            String cryptResult = Convert.ToBase64String(cryptBytes);

            return cryptResult;     // 암호화 문자열 리턴.

        }

        public static String decrypt(String text, String password)

        {

            RijndaelManaged RijndaelCipher = new RijndaelManaged();

            byte[] encryptData = Convert.FromBase64String(text);

            byte[] salt = Encoding.UTF8.GetBytes(password);

            PasswordDeriveBytes SecretKey = new PasswordDeriveBytes(password, salt);

            ICryptoTransform Decryptor = RijndaelCipher.CreateDecryptor(SecretKey.GetBytes(32), SecretKey.GetBytes(16));

            MemoryStream memoryStream = new MemoryStream(encryptData);

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

            byte[] PlainText = new byte[encryptData.Length];

            // 복호화 시작

            int DecryptedCount = cryptoStream.Read(PlainText, 0, PlainText.Length);

            memoryStream.Close();

            cryptoStream.Close();

            // 복호화된 데이터를 문자열로 바꾼다.

            string DecryptedData = Encoding.UTF8.GetString(PlainText, 0, DecryptedCount);

            // 최종 결과 리턴

            return DecryptedData;

        }

    }

}