using System;

using static System.Console;

using System.Security.Cryptography;

using System.Text;

public class Program

{

    private const string IV = "HR$2pIjHR$2pIj12";

​

    public static void Main()

    {

        var senha = "123";

        var entrada = "teste22";

​

        var cripto = criptografar(senha, entrada);

        var cripto64 = Convert.ToBase64String(cripto);

        WriteLine($"Representação em string (em base64) da criptografia: {cripto64}");

​

        var decrip = descriptografar(senha, cripto);

        WriteLine($"Texto original (pelo byte[]): {Encoding.UTF8.GetString(decrip)}");

​

        var bytes = Convert.FromBase64String(cripto64);

        var decBase64 = descriptografar(senha, bytes);

        WriteLine($"Texto original (string base64): {Encoding.UTF8.GetString(decBase64)}");

    }

​

    static byte[] criptografar(string senha, string entrada)

    {

        string keyMd5 = Encryptor.GerarHashMd5(senha);

        return Encryptor.encryptdata(Encoding.UTF8.GetBytes(entrada), keyMd5, IV);

    }

​

    static byte[] descriptografar(string senha, byte[] criptografado)

    {

        string keyMd5 = Encryptor.GerarHashMd5(senha);                      

        return Encryptor.decryptdata(criptografado, keyMd5, IV);

    }

}

​

​

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();

        dataencrypt.BlockSize = 128;

        dataencrypt.KeySize = 128;

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

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

        dataencrypt.Padding = PaddingMode.PKCS7;

        dataencrypt.Mode = CipherMode.CBC; 

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

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

        crypto1.Dispose();

        return encrypteddata;

    }

​

    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;

    }

}