using System;

using static System.Console;

using System.Security.Cryptography;

using System.Text;

public class Program

{

    public static void Main()

    {

        var senha = "123";

        var entrada = "teste22";

        criptografar(senha, entrada);

    }

    static void criptografar(string senha, string entrada)

    {

        string iv = "HR$2pIjHR$2pIj12"; // aleatório

        string keyMd5 = Encryptor.GerarHashMd5(senha);

        WriteLine($"Hash MD5: {keyMd5}");

        byte[] encrypted = Encryptor.encryptdata(Encoding.UTF8.GetBytes(entrada), keyMd5, iv); // encryptador   

        var crip = Encoding.UTF8.GetString(encrypted);

        WriteLine($"Saida.Text: {crip}");

    }

    static void descriptografar_Click(string senha, string entrada)

    {

        string iv = "HR$2pIjHR$2pIj12"; // aleatório

        string keyMd5 = Encryptor.GerarHashMd5(senha);

        WriteLine($"Hash MD5: {keyMd5}");

        byte[] textArray = Encoding.UTF8.GetBytes(entrada);

        byte[] input = Encryptor.encryptdata(textArray, keyMd5, iv);        

        byte[] decrypted = Encryptor.decryptdata(input, keyMd5, iv); // decryptador

        WriteLine($"Saida.Text: {Encoding.UTF8.GetString(decrypted)}");

    }

}

​

class Encryptor

{

    public static string GerarHashMd5(string input)

    {

        MD5 md5Hash = MD5.Create();

        byte[] data = md5Hash.ComputeHash(Encoding.UTF8.GetBytes(input));

​

        StringBuilder sBuilder = new StringBuilder();

​

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

        {

            sBuilder.Append(data[i].ToString("x2"));

        }

​

        return sBuilder.ToString();

    }

​

    //AES

    static public byte[] encryptdata(byte[] bytearraytoencrypt, string key, string iv)

    {

        AesCryptoServiceProvider dataencrypt = new AesCryptoServiceProvider();

        //Block size : Gets or sets the block size, in bits, of the cryptographic operation.  

        dataencrypt.BlockSize = 128;

        //KeySize: Gets or sets the size, in bits, of the secret key  

        dataencrypt.KeySize = 128;

        //Key: Gets or sets the symmetric key that is used for encryption and decryption.  

        dataencrypt.Key = System.Text.Encoding.UTF8.GetBytes(key);

        //IV : Gets or sets the initialization vector (IV) for the symmetric algorithm  

        dataencrypt.IV = System.Text.Encoding.UTF8.GetBytes(iv);

        //Padding: Gets or sets the padding mode used in the symmetric algorithm  

        dataencrypt.Padding = PaddingMode.PKCS7;

        //Mode: Gets or sets the mode for operation of the symmetric algorithm  

        dataencrypt.Mode = CipherMode.CBC;

        //Creates a symmetric AES encryptor object using the current key and initialization vector (IV).  

        ICryptoTransform crypto1 = dataencrypt.CreateEncryptor(dataencrypt.Key, dataencrypt.IV);

        //TransformFinalBlock is a special function for transforming the last block or a partial block in the stream.   

        //It returns a new array that contains the remaining transformed bytes. A new array is returned, because the amount of   

        //information returned at the end might be larger than a single block when padding is added.  

        byte[] encrypteddata = crypto1.TransformFinalBlock(bytearraytoencrypt, 0, bytearraytoencrypt.Length);

        crypto1.Dispose();

        //return the encrypted data  

        return encrypteddata;

    }

​

    //code to decrypt data

    static public byte[] decryptdata(byte[] bytearraytodecrypt, string key, string iv)

    {

​

        AesCryptoServiceProvider keydecrypt = new AesCryptoServiceProvider();

        keydecrypt.BlockSize = 128;

        keydecrypt.KeySize = 128;

        keydecrypt.Key = System.Text.Encoding.UTF8.GetBytes(key);

        keydecrypt.IV = System.Text.Encoding.UTF8.GetBytes(iv);

        keydecrypt.Padding = PaddingMode.PKCS7;

        keydecrypt.Mode = CipherMode.CBC;

        ICryptoTransform crypto1 = keydecrypt.CreateDecryptor(keydecrypt.Key, keydecrypt.IV);

​

        byte[] returnbytearray = crypto1.TransformFinalBlock(bytearraytodecrypt, 0, bytearraytodecrypt.Length);

        crypto1.Dispose();

        return returnbytearray;

    }

}