using System;

using System.IO;

using System.Security.Cryptography;

using System.Text;

using Newtonsoft.Json;

​

public class KeyGen

{

    public static void Main(string[] args)

    {

        // Simulated unique software key

        string uniqueSoftwareKey = "YourSoftwareKeyHere";

​

        // Simulated MAC address of the network interface

        string fakeMacAddress = "00-14-22-01-23-45";

​

        // Create a SecurityModel object with fake purchase code and correct item ID

        SecurityModel securityModel = new SecurityModel

        {

            PurchaseCode = "7b153b71-ea9e-4fe1-ab25-b7ba31b66d60",

            itemId = "T2VqYktRUzd3R3J6UFBjaG1yMUMrQT09"  // Correct ItemId as per the original logic

        };

​

        // Generate the key (encrypted form of SecurityModel)

        string generatedKey = GenerateKey(fakeMacAddress, uniqueSoftwareKey, securityModel);

        Console.WriteLine("Generated Key: " + generatedKey);

​

        // Decrypt the generated key and verify the output

        SecurityModel decryptedModel = Decrypt(generatedKey);

        Console.WriteLine("Decrypted Purchase Code: " + decryptedModel.PurchaseCode);

        Console.WriteLine("Decrypted Item ID: " + decryptedModel.itemId);

    }

​

    // Generates an encryption key using the MAC address and the unique software key

    public static string GenerateKey(string macAddress, string uniqueSoftwareKey, SecurityModel securityModel)

    {

        // Combine the MAC address and unique software key to create key material

        string keyMaterial = macAddress + uniqueSoftwareKey;

​

        // Encrypt the SecurityModel object and return the encrypted string

        return Encrypt(securityModel, keyMaterial);

    }

​

    // Encrypts the SecurityModel object into a Base64 encoded string

    public static string Encrypt(SecurityModel securityModel, string keyMaterial)

    {

        string strPassword = "hhL:WV*7<dgeKY)fjTe>'[9+`GyzS&]3;k8UGKK_&2]!";

        string salt = "q$3}T&qtpTJ>q\t/'/;wh!#%H77e'3AXA(*(qcL%=**)";

        string strHashName = "SHA1";

        int iterations = 2;

        string ivString = "@1B2c3D4e5F6g7H8";

        int keySize = 256;

​

        // Convert IV and salt to byte arrays

        byte[] iv = Encoding.ASCII.GetBytes(ivString);

        byte[] saltBytes = Encoding.ASCII.GetBytes(salt);

        byte[] keyBytes = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(securityModel));

​

        // Derive the key using the provided password and salt

        PasswordDeriveBytes passwordDeriveBytes = new PasswordDeriveBytes(strPassword, saltBytes, strHashName, iterations);

        byte[] key = passwordDeriveBytes.GetBytes(keySize / 8);

​

        // Create Rijndael (AES) encryption

        RijndaelManaged rijndaelManaged = new RijndaelManaged();

        rijndaelManaged.Mode = CipherMode.CBC;

​

        // Encrypt the key bytes using the derived key and IV

        ICryptoTransform encryptor = rijndaelManaged.CreateEncryptor(key, iv);

​

        using (MemoryStream memoryStream = new MemoryStream())

        {

            using (CryptoStream cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))

            {

                cryptoStream.Write(keyBytes, 0, keyBytes.Length);

                cryptoStream.FlushFinalBlock();

                byte[] encryptedBytes = memoryStream.ToArray();

                return Convert.ToBase64String(encryptedBytes);  // Return the encrypted string as Base64

            }

        }

    }

​

    // Decrypts the given Base64 encoded cipher text and returns a SecurityModel object

    public static SecurityModel Decrypt(string cipherText)

    {

        string strPassword = "hhL:WV*7<dgeKY)fjTe>'[9+`GyzS&]3;k8UGKK_&2]!";

        string salt = "q$3}T&qtpTJ>q\t/'/;wh!#%H77e'3AXA(*(qcL%=**)";

        string strHashName = "SHA1";

        int iterations = 2;

        string ivString = "@1B2c3D4e5F6g7H8";

        int keySize = 256;

​

        // Convert IV and salt to byte arrays

        byte[] iv = Encoding.ASCII.GetBytes(ivString);

        byte[] saltBytes = Encoding.ASCII.GetBytes(salt);

        byte[] cipherBytes = Convert.FromBase64String(cipherText);

​

        // Derive the key using the provided password and salt

        PasswordDeriveBytes passwordDeriveBytes = new PasswordDeriveBytes(strPassword, saltBytes, strHashName, iterations);

        byte[] key = passwordDeriveBytes.GetBytes(keySize / 8);

​

        // Create Rijndael (AES) decryption

        RijndaelManaged rijndaelManaged = new RijndaelManaged();

        rijndaelManaged.Mode = CipherMode.CBC;

​

        // Decrypt the cipher bytes using the derived key and IV

        ICryptoTransform decryptor = rijndaelManaged.CreateDecryptor(key, iv);

​

        using (MemoryStream memoryStream = new MemoryStream(cipherBytes))

        {

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

            {

                byte[] decryptedBytes = new byte[cipherBytes.Length];

                int decryptedByteCount = cryptoStream.Read(decryptedBytes, 0, decryptedBytes.Length);

                string decryptedText = Encoding.UTF8.GetString(decryptedBytes, 0, decryptedByteCount);

​

                // Deserialize the decrypted text back into a SecurityModel object

                return JsonConvert.DeserializeObject<SecurityModel>(decryptedText);

            }

        }

    }

}

​

// Simulates the SecurityModel class structure used in the encryption/decryption process

public class SecurityModel

{

    public string PurchaseCode { get; set; }

    public string itemId { get; set; }

}