/// <summary>
/// Encrypt String using specified Algorithm
/// </summary>
/// <param name="targetValue"></param>
/// <param name="cryptoAlgorithm"></param>
/// <returns></returns>
public byte[] Encrypt(string targetValue, eSymmetricCryptoAlgorithm cryptoAlgorithm)
{
byte[] arrEncryptedValue = null;
if (targetValue.Length > 0)
{
arrEncryptedValue = SymmetricCrypto(cryptoAlgorithm,
eCryptoMode.Encrypt,
System.Text.Encoding.UTF8.GetBytes(targetValue),
marrEncryptionKey,
marrEncryptionVector);
}
return arrEncryptedValue;
}
/// <summary>
/// Encrypt File using specified Algorithm
/// </summary>
/// <param name="targetValue"></param>
/// <param name="cryptoAlgorithm"></param>
/// <returns></returns>
public byte[] Encrypt(FileStream decryptedFile, eSymmetricCryptoAlgorithm cryptoAlgorithm)
{
byte[] arrEncryptedValue = null;
byte[] buffer = null;
buffer = new byte[decryptedFile.Length];
decryptedFile.Read(buffer, 0, buffer.Length);
decryptedFile.Close();
arrEncryptedValue = SymmetricCrypto(cryptoAlgorithm,
eCryptoMode.Encrypt,
buffer,
marrEncryptionKey,
marrEncryptionVector);
return arrEncryptedValue;
}
/// <summary>
/// Get Encryption Provider appropriate to eSymmetricCryptoAlgorithm value specified
/// </summary>
/// <param name="Algorithm"></param>
/// <returns></returns>
private System.Security.Cryptography.SymmetricAlgorithm GetSymmetricEncryptionProvider(eSymmetricCryptoAlgorithm Algorithm)
{
// Return a provider to match our chosen encryption algorithm
// ==========================================================
SymmetricAlgorithm objReturn = null;
// Generate crypto provider
switch(Algorithm)
{
case eSymmetricCryptoAlgorithm.DES:
{
objReturn = new DESCryptoServiceProvider();
break;
}
case eSymmetricCryptoAlgorithm.RC2:
{
objReturn = new RC2CryptoServiceProvider();
break;
}
case eSymmetricCryptoAlgorithm.Rinjdael:
{
objReturn = new RijndaelManaged();
break;
}
case eSymmetricCryptoAlgorithm.TripleDES:
{
objReturn = new TripleDESCryptoServiceProvider();
break;
}
}
// Apply standard parameters to this provider
// (None to be applied at this time)
// Return provider
return objReturn;
}
/// <summary>
/// Performs Encryption\Decryption using specified Algorithm, Key, and Vector
/// </summary>
/// <param name="cryptoAlgorithm"></param>
/// <param name="cryptoMode"></param>
/// <param name="inputData"></param>
/// <param name="encryptionKey"></param>
/// <param name="encryptionVector"></param>
/// <returns></returns>
private byte[] SymmetricCrypto(eSymmetricCryptoAlgorithm cryptoAlgorithm, eCryptoMode cryptoMode, byte[] inputData, byte[] encryptionKey, byte[] encryptionVector)
{
SymmetricAlgorithm cryptProvider;
ICryptoTransform cryptEngine = null;
MemoryStream objCryptoStream;
CryptoStream objCryptoProcess;
byte[] arrOutputData;
// Create encryption provider - required for validation steps below
// ----------------------------------------------------------------
cryptProvider = GetSymmetricEncryptionProvider(cryptoAlgorithm);
// Validate contents of byte arrays
// --------------------------------
if (ValidateSymmetricalEncryptionParameters(cryptProvider, ref inputData, ref encryptionKey, ref encryptionVector, cryptoMode) == false)
{
return null;
}
// Attach Key and Vector to cryptProvider
cryptProvider.Key = encryptionKey;
cryptProvider.IV = encryptionVector;
// Encrypt\Decrypt
objCryptoStream = new MemoryStream();
switch (cryptoMode)
{
case eCryptoMode.Encrypt:
{
cryptEngine = cryptProvider.CreateEncryptor();
break;
}
case eCryptoMode.Decrypt:
{
cryptEngine = cryptProvider.CreateDecryptor();
break;
}
}
// Encrypted\Decrypt value into a Stream
objCryptoProcess = new CryptoStream(objCryptoStream, cryptEngine, CryptoStreamMode.Write);
objCryptoProcess.Write(inputData, 0, inputData.Length);
objCryptoProcess.Close();
// Extract Encrypted\Decrypted value from Stream
arrOutputData = objCryptoStream.ToArray();
cryptEngine = null;
cryptProvider = null;
objCryptoStream = null;
objCryptoProcess = null;
return arrOutputData;
}
/// <summary>
/// Return a Vector appropriate to the specified CryptoAlgorithm
/// </summary>
/// <param name="Algorithm"></param>
/// <returns></returns>
public string GetSymmetricVector(eSymmetricCryptoAlgorithm Algorithm)
{
SymmetricAlgorithm cryptEngine;
string strReturn;
// Use Crypto Engine and generate Vector
cryptEngine = GetSymmetricEncryptionProvider(Algorithm);
strReturn = GetSymmetricVector(cryptEngine);
cryptEngine = null;
return strReturn;
}
/// <summary>
/// Decrypt to String using specified Algorithm
/// </summary>
/// <param name="targetValue"></param>
/// <param name="cryptoAlgorithm"></param>
/// <returns></returns>
public string Decrypt(byte[] targetValue, eSymmetricCryptoAlgorithm cryptoAlgorithm)
{
byte[] arrDecryptedValue = null;
string strDecryptedValue = string.Empty;
if (targetValue.Length >= 8)
{
arrDecryptedValue = SymmetricCrypto(cryptoAlgorithm,
eCryptoMode.Decrypt,
targetValue,
marrEncryptionKey,
marrEncryptionVector);
strDecryptedValue = System.Text.Encoding.UTF8.GetString(arrDecryptedValue);
}
return strDecryptedValue;
}
