using System;

using System.IO;

using System.Text;

using System.Security.Cryptography;

​

//// C# Console Program for Parking API Data Encryption for request

public class Program

{

    private const int HashIterations = 1024; // iteration (fixed)

    public static void Main()

    {

        // Deriving Key

        var password = "sinagama"; // key (fixed)

        var salt = new Byte[]{172, 137, 25, 56, 156, 100, 136, 211, 84, 67, 96, 10, 24, 111, 112, 137, 3}; // salt (fixed)

        byte[] derivedKey = GeneratePasswordHash(password, salt); // derive the key to 16 bytes

        // Encryption

        string TRANS_ID="DP1000520210628165440";

        //string SALES_RECEIPT_NO="FP001-210628-000009";

        string TRANS_TYPE="P";

        string MER_TOKEN="VN1Q0UC5IA72QTXW";

        string ivKey="1234567890123456";

​

        // Create a new instance of the AesManaged class.

        // This generates a new initialization vector (IVKey).

        using (AesManaged myAes = new AesManaged())

        {

            byte[] ivkey = Encoding.ASCII.GetBytes(ivKey);

            // Encrypts data

            string encryptedTRANS_ID=EncryptStringToBytes_Aes(TRANS_ID, derivedKey, ivkey);

            //string encryptedSALES_RECEIPT_NO=EncryptStringToBytes_Aes(SALES_RECEIPT_NO, derivedKey, ivkey);

            string encryptedTRANS_TYPE=EncryptStringToBytes_Aes(TRANS_TYPE, derivedKey, ivkey);

            string encryptedMER_TOKEN=EncryptStringToBytes_Aes(MER_TOKEN, derivedKey, ivkey);

            // Output

            Console.WriteLine("{");

            Console.WriteLine("TRANS_ID:{0}", encryptedTRANS_ID);

            //Console.WriteLine("SALES_RECEIPT_NO:{0}", encryptedSALES_RECEIPT_NO);

            Console.WriteLine("TRANS_TYPE:{0}", encryptedTRANS_TYPE);

            Console.WriteLine("MER_TOKEN:{0}", encryptedMER_TOKEN);

            Console.WriteLine("IvKey:{0}", ivKey);

            Console.WriteLine("}");

        }

    }

    static string EncryptStringToBytes_Aes(string plainText, byte[] Key, byte[] IV)

    {

        // Check arguments.

        if (plainText == null)

            throw new ArgumentNullException("plainText");

        if (Key == null || Key.Length <= 0)

            throw new ArgumentNullException("Key");

        if (IV == null || IV.Length <= 0)

            throw new ArgumentNullException("IV");

        byte[] encrypted;

​

        // Create an AesManaged object

        // with the specified key and IV.

        using (AesManaged aesAlg = new AesManaged())

        {

            aesAlg.Key = Key;

            aesAlg.IV = IV;

​

            // Create an encryptor to perform the stream transform.

            ICryptoTransform encryptor = aesAlg.CreateEncryptor(aesAlg.Key, aesAlg.IV);

​

            // Create the streams used for encryption.

            using (MemoryStream msEncrypt = new MemoryStream())

            {

                using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))

                {

                    using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))

                    {

                        //Write all data to the stream.

                        swEncrypt.Write(plainText);

                    }

                    encrypted = msEncrypt.ToArray();

                }

            }

        }

​

        // Return the encrypted bytes from the memory stream.

        return Convert.ToBase64String(encrypted);

    }

​

    public static byte[] GeneratePasswordHash(string password, Byte[] salt, int hashIterations = HashIterations)

    {

        byte[] hash;

        using (var crypto = new Rfc2898DeriveBytes(password, salt, hashIterations, HashAlgorithmName.SHA1))

        {

            hash = crypto.GetBytes(16);

        }

​

        return hash;

    }

    static string ComputeSha256Hash(string rawData)  

    {  

        // Create a SHA256   

        using (SHA256 sha256Hash = SHA256.Create())  

        {  

            // ComputeHash - returns byte array  

            byte[] bytes = sha256Hash.ComputeHash(Encoding.UTF8.GetBytes(rawData));  

​

            // Convert byte array to a string   

            StringBuilder builder = new StringBuilder();  

            for (int i = 0; i < bytes.Length; i++)  

            {  

                builder.Append(bytes[i].ToString("x2"));  

            }  

            return builder.ToString();  

        }  

    }  

}