private T Decrypt(Byte[] ciphertext, PinnedBuffer key, SymmetricAlgorithmSpecification algorithm)
{
using (var cipher = algorithm.ToCipher(RandomnessProvider))
{
using (var pinnedCiphertext = new PinnedBuffer(ciphertext, false))
{
using (var plaintext = cipher.Decrypt(pinnedCiphertext, key))
{
return(BinarySerializer.Deserialize(plaintext));
}
}
}
}
private Byte[] Encrypt(T plaintextObject, PinnedBuffer key, SymmetricAlgorithmSpecification algorithm, Byte[] initializationVector)
{
var plaintext = BinarySerializer.Serialize(plaintextObject);
var plaintextLength = plaintext.Length;
using (var pinnedPlaintext = new PinnedBuffer(plaintextLength, true))
{
Array.Copy(plaintext, pinnedPlaintext, plaintextLength);
using (var cipher = algorithm.ToCipher(RandomnessProvider))
{
switch (cipher.Mode)
{
case CipherMode.CBC:
using (var processedInitializationVector = new PinnedBuffer(cipher.BlockSizeInBytes, true))
{
if (initializationVector is null)
{
RandomnessProvider.GetBytes(processedInitializationVector);
}
else
{
Array.Copy(initializationVector.RejectIf(argument => argument.Length < cipher.BlockSizeInBytes, nameof(initializationVector)), processedInitializationVector, cipher.BlockSizeInBytes);
}
return(cipher.Encrypt(pinnedPlaintext, key, processedInitializationVector));
}
case CipherMode.ECB:
return(cipher.Encrypt(pinnedPlaintext, key, null));
default:
throw new InvalidOperationException($"The specified cipher mode, {cipher.Mode}, is not supported.");
}
}
}
}