// This method is not compatible with the one provided by MS in
// framework 1.0 and 1.1 but IS compliant with PKCS#1 v.2.1 and
// work for implementing OAEP
public override byte[] GenerateMask(byte[] rgbSeed, int cbReturn)
{
HashAlgorithm hash = HashAlgorithm.Create(hashName);
return(PKCS1.MGF1(hash, rgbSeed, cbReturn));
}