Encryption Decryption Helper

Encryption Decryption Helper

public class clsEncryptionDecryption

{

#region Variable Declaration

private static string keyString = "keyString";

#endregion

#region Methods/Functions

/// <summary>

/// Get Encrpted Value of Passed value

/// </summary>

/// <param name="value"></param>

/// <returns></returns>

/// <remarks></remarks>

public static string GetEncrypt(string value)

{

return Encrypt(keyString, value);

}

/// <summary>

/// Get Decrypted value of passed encrypted string

/// </summary>

/// <param name="value"></param>

/// <returns></returns>

/// <remarks></remarks>

public static string GetDecrypt(string value)

{

return Decrypt(keyString, value);

}

/// <summary>

/// Encrypt value

/// </summary>

/// <param name="Passphrase"></param>

/// <param name="Message"></param>

/// <returns></returns>

/// <remarks></remarks>

private static string Encrypt(string Passphrase, string Message)

{

using (MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider())

{

byte[] Results;

System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();

// Step 1. We hash the passphrase using MD5

// We use the MD5 hash generator as the result is a 128 bit byte array

// which is a valid length for the TripleDES encoder we use below

byte[] TDESKey = HashProvider.ComputeHash(UTF8.GetBytes(Passphrase));

// Step 2. Create a new TripleDESCryptoServiceProvider object

using (TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider())

{

// Step 3. Setup the encoder

TDESAlgorithm.Key = TDESKey;

TDESAlgorithm.Mode = CipherMode.ECB;

TDESAlgorithm.Padding = PaddingMode.PKCS7;

// Step 4. Convert the input string to a byte[]

byte[] DataToEncrypt = UTF8.GetBytes(Message);

// Step 5. Attempt to encrypt the string

try

{

ICryptoTransform Encryptor = TDESAlgorithm.CreateEncryptor();

Results = Encryptor.TransformFinalBlock(DataToEncrypt, 0, DataToEncrypt.Length);

}

finally

{

// Clear the TripleDes and Hashprovider services of any sensitive information

TDESAlgorithm.Clear();

HashProvider.Clear();

}

// Step 6. Return the encrypted string as a base64 encoded string

return Convert.ToBase64String(Results);

//}

//catch (Exception)

//{

// throw;

//}

}

}

}

/// <summary>

/// decrypt value

/// </summary>

/// <param name="Passphrase"></param>

/// <param name="Message"></param>

/// <returns></returns>

/// <remarks></remarks>

private static string Decrypt(string Passphrase, string Message)

{

if (string.IsNullOrEmpty(Message))

return string.Empty;

using (MD5CryptoServiceProvider HashProvider = new MD5CryptoServiceProvider())

{

byte[] Results;

System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();

// Step 1. We hash the passphrase using MD5

// We use the MD5 hash generator as the result is a 128 bit byte array

// which is a valid length for the TripleDES encoder we use below

byte[] TDESKey = HashProvider.ComputeHash(UTF8.GetBytes(Passphrase));

// Step 2. Create a new TripleDESCryptoServiceProvider object

using (TripleDESCryptoServiceProvider TDESAlgorithm = new TripleDESCryptoServiceProvider())

{

// Step 3. Setup the decoder

TDESAlgorithm.Key = TDESKey;

TDESAlgorithm.Mode = CipherMode.ECB;

TDESAlgorithm.Padding = PaddingMode.PKCS7;

Message = Message.Replace(" ", "+"); // Replace space with plus sign in encrypted value if any.- 

// Step 4. Convert the input string to a byte[]

byte[] DataToDecrypt = Convert.FromBase64String(Message);

// Step 5. Attempt to decrypt the string

try

{

ICryptoTransform Decryptor = TDESAlgorithm.CreateDecryptor();

Results = Decryptor.TransformFinalBlock(DataToDecrypt, 0, DataToDecrypt.Length);

}

catch

{

return "";

}

finally

{

// Clear the TripleDes and Hashprovider services of any sensitive information

TDESAlgorithm.Clear();

HashProvider.Clear();

}

// Step 6. Return the decrypted string in UTF8 format

return UTF8.GetString(Results);

//}

//catch (Exception)

//{

// throw;

//}

}

}

}

#endregion

}