using Org.BouncyCastle.Crypto;

using Org.BouncyCastle.Crypto.Digests;

using Org.BouncyCastle.Crypto.Parameters;

using Org.BouncyCastle.Security;

using System;

using System.IO;

using System.Security.Cryptography;

using System.Text;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(MWEncryptDecrypt.Encrypt("put your plain password here"));

    }

    public static class MWEncryptDecrypt

    {

        private static readonly string encryptionMode = "AES/OFB/PKCS5PADDING";

        private static readonly string algorithm = "AES";

​

        /// <summary>

        /// This method is used to encrypt the data with the password

        /// </summary>

        /// <param name="data">Data to be encrypted</param>

        /// <param name="password">Password which will be used to encrypt the data</param>

        /// <returns>encrypted value in string format</returns>

        public static string Encrypt(string data, string password ="RhA0IkUSSUkI0AhROxAjMCNEENCMjAxO")

        {

            try

            {

                // Get UTF8 byte array of input string for encryption

                byte[] inputBytes = ASCIIEncoding.UTF8.GetBytes(data);

​

                // Again, get UTF8 byte array of key for use in encryption

                byte[] keyBytes = ASCIIEncoding.UTF8.GetBytes(password);

​

                // Initialize AES OFB (counter) mode cipher from the BouncyCastle cryptography library

                IBufferedCipher cipher = CipherUtilities.GetCipher(encryptionMode);

​

                // Set cipher parameters to use the encryption key we defined above for encryption

                // Since we are encrypting using the CTR mode / algorithm, the cipher is operating as a stream cipher.

                // For perfect secrecy with a stream cipher, we should be generating a stream of pseudorandom characters called a keystream,

                // then XOR'ing that with the plaintext. Instead, for convenience we are just XOR'ing the first [blocksize] bytes of null values.

                // While convenient, as we only need a single key for two way encryption/decryption, this method is vulnerable to a simple known-plaintext attack

                // As such, it should not be relied upon for true secrecy, only for security through obscurity.

                cipher.Init(true, new ParametersWithIV(ParameterUtilities.CreateKeyParameter(algorithm, keyBytes), new byte[16]));

​

                // As this is a stream cipher, you can process bytes chunk by chunk until complete, then close with DoFinal.

                // In our case we don't need a stream, so we simply call DoFinal() to encrypt the entire input at once.

                byte[] encryptedBytes = cipher.DoFinal(inputBytes);

​

                // The encryption is complete, however we still need to get the encrypted byte array into a useful form for passing as a URL parameter

                // First, we convert the encrypted byte array to a Base64 string to make it use ASCII characters

                string base64EncryptedOutputString = Convert.ToBase64String(encryptedBytes);

​

                // Lastly, we replace the 2 characters from Base64 which are not URL safe ( + and / ) with ( - and _ ) as recommended in IETF RFC4648

                //string urlEncodedBase64EncryptedOutputString = base64EncryptedOutputString.Replace("+", "-").Replace("/", "_");

​

                // This final string is now safe to be passed around, into our web service by URL, etc.

                return base64EncryptedOutputString;

            }

            catch (Exception)

            {

                throw;

            }

        }

    }

}