		const EVP_PKEY* _pEVP;
		EVPPKeyContext  _pCtx;
		int             _blockSize;
		std::streamsize _pos;
		unsigned char*  _pBuf;
	};


	class EVPDecryptImpl: public CryptoTransform
	{
	public:
		EVPDecryptImpl(const EVP_PKEY* pEVP):
			_pEVP(pEVP),
			_pCtx(_pEVP),