/// <summary>
/// test using user-provided keys and init vectors
/// </summary>
private static string SymmetricWithKey(SymmetricProvider p, string targetString)
{
var keyData = new SymmetricKeyData("MySecretPassword");
var ivData = new SymmetricKeyData("MyInitializationVector");
Data encryptedData;
using (var sym = new Symmetric(p, false))
{
sym.IntializationVector = ivData;
encryptedData = sym.Encrypt(new Data(targetString), keyData);
}
Data decryptedData;
using (var sym2 = new Symmetric(p, false))
{
sym2.IntializationVector = ivData;
decryptedData = sym2.Decrypt(encryptedData, keyData);
}
////-- the data will be padded to the encryption blocksize, so we need to trim it back down.
//return decryptedData.ToString().Substring(0, _TargetData.Bytes.Length);
return decryptedData.ToString();
}
/// <summary>
/// Ensures that the _crypto object has valid Key and IV prior to any attempt to encrypt or decrypt.
/// </summary>
private void ValidateKeyAndIv(bool isEncrypting)
{
if (_key.IsEmpty)
{
if (isEncrypting)
{
_key = RandomKey();
}
else
{
throw new CryptographicException("No key was provided for the decryption operation!");
}
}
if (_iv.IsEmpty)
{
if (isEncrypting)
{
_iv = RandomInitializationVector();
}
else
{
throw new CryptographicException("No initialization vector was provided for the decryption operation!");
}
}
_crypto.Key = _key.Bytes;
_crypto.IV = _iv.Bytes;
}
/// <summary>
/// Encrypts the specified stream to memory using the provided key.
/// </summary>
/// <exception cref="T:System.ArgumentNullException">stream is null.</exception>
public Data Encrypt(Stream stream, SymmetricKeyData key)
{
Key = key;
return Encrypt(stream);
}
/// <summary>
/// Encrypts the specified stream to memory using the provided key and initialization vector.
/// </summary>
/// <exception cref="T:System.ArgumentNullException">stream is null.</exception>
public Data Encrypt(Stream stream, SymmetricKeyData key, SymmetricKeyData iv)
{
IntializationVector = iv;
Key = key;
return Encrypt(stream);
}
/// <summary>
/// Encrypts the specified data using the provided key.
/// </summary>
/// <exception cref="T:System.ArgumentNullException">data is null.</exception>
public Data Encrypt(Data d, SymmetricKeyData key)
{
Key = key;
return Encrypt(d);
}
/// <summary>
/// Decrypts the specified data using provided key and preset initialization vector.
/// </summary>
/// <exception cref="T:System.ArgumentNullException">data is null.</exception>
/// <exception cref="T:System.Security.Cryptography.CryptographicException">Unable to decrypt data.</exception>
public Data Decrypt(Data data, SymmetricKeyData key)
{
Key = key;
return Decrypt(data);
}
