using System;
using System.IO;
using System.Security.Cryptography;
/// <summary>
/// encrypt and decrypt strings
/// </summary>
public class Encryption
{
/// <summary>
/// Encrypts the string.
/// </summary>
/// <param name="clearText">The clear text.</param>
/// <param name="Key">The key.</param>
/// <param name="IV">The IV.</param>
/// <returns></returns>
private static byte[] EncryptString(byte[] clearText, byte[] Key, byte[] IV)
{
MemoryStream ms = new MemoryStream();
Rijndael alg = Rijndael.Create();
alg.Key = Key;
alg.IV = IV;
CryptoStream cs = new CryptoStream(ms, alg.CreateEncryptor(), CryptoStreamMode.Write);
cs.Write(clearText, 0, clearText.Length);
cs.Close();
byte[] encryptedData = ms.ToArray();
return encryptedData;
}
/// <summary>
/// Encrypts the string.
/// </summary>
/// <param name="clearText">The clear text.</param>
/// <param name="Password">The password.</param>
/// <returns></returns>
public static string EncryptString(string clearText, string Password)
{
byte[] clearBytes = System.Text.Encoding.Unicode.GetBytes(clearText);
PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
byte[] encryptedData = EncryptString(clearBytes, pdb.GetBytes(32), pdb.GetBytes(16));
return Convert.ToBase64String(encryptedData);
}
/// <summary>
/// Decrypts the string.
/// </summary>
/// <param name="cipherData">The cipher data.</param>
/// <param name="Key">The key.</param>
/// <param name="IV">The IV.</param>
/// <returns></returns>
private static byte[] DecryptString(byte[] cipherData, byte[] Key, byte[] IV)
{
MemoryStream ms = new MemoryStream();
Rijndael alg = Rijndael.Create();
alg.Key = Key;
alg.IV = IV;
CryptoStream cs = new CryptoStream(ms, alg.CreateDecryptor(), CryptoStreamMode.Write);
cs.Write(cipherData, 0, cipherData.Length);
cs.Close();
byte[] decryptedData = ms.ToArray();
return decryptedData;
}
/// <summary>
/// Decrypts the string.
/// </summary>
/// <param name="cipherText">The cipher text.</param>
/// <param name="Password">The password.</param>
/// <returns></returns>
public static string DecryptString(string cipherText, string Password)
{
byte[] cipherBytes = Convert.FromBase64String(cipherText);
PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
byte[] decryptedData = DecryptString(cipherBytes, pdb.GetBytes(32), pdb.GetBytes(16));
return System.Text.Encoding.Unicode.GetString(decryptedData);
}
}