boost/asio/ssl/detail/engine.hpp
//
// ssl/detail/engine.hpp
// ~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2023 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#ifndef BOOST_ASIO_SSL_DETAIL_ENGINE_HPP
#define BOOST_ASIO_SSL_DETAIL_ENGINE_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include <boost/asio/detail/config.hpp>
#include <boost/asio/buffer.hpp>
#include <boost/asio/detail/static_mutex.hpp>
#include <boost/asio/ssl/detail/openssl_types.hpp>
#include <boost/asio/ssl/detail/verify_callback.hpp>
#include <boost/asio/ssl/stream_base.hpp>
#include <boost/asio/ssl/verify_mode.hpp>
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
namespace ssl {
namespace detail {
class engine
{
public:
enum want
{
// Returned by functions to indicate that the engine wants input. The input
// buffer should be updated to point to the data. The engine then needs to
// be called again to retry the operation.
want_input_and_retry = -2,
// Returned by functions to indicate that the engine wants to write output.
// The output buffer points to the data to be written. The engine then
// needs to be called again to retry the operation.
want_output_and_retry = -1,
// Returned by functions to indicate that the engine doesn't need input or
// output.
want_nothing = 0,
// Returned by functions to indicate that the engine wants to write output.
// The output buffer points to the data to be written. After that the
// operation is complete, and the engine does not need to be called again.
want_output = 1
};
// Construct a new engine for the specified context.
BOOST_ASIO_DECL explicit engine(SSL_CTX* context);
// Construct a new engine for an existing native SSL implementation.
BOOST_ASIO_DECL explicit engine(SSL* ssl_impl);
#if defined(BOOST_ASIO_HAS_MOVE)
// Move construct from another engine.
BOOST_ASIO_DECL engine(engine&& other) BOOST_ASIO_NOEXCEPT;
#endif // defined(BOOST_ASIO_HAS_MOVE)
// Destructor.
BOOST_ASIO_DECL ~engine();
#if defined(BOOST_ASIO_HAS_MOVE)
// Move assign from another engine.
BOOST_ASIO_DECL engine& operator=(engine&& other) BOOST_ASIO_NOEXCEPT;
#endif // defined(BOOST_ASIO_HAS_MOVE)
// Get the underlying implementation in the native type.
BOOST_ASIO_DECL SSL* native_handle();
// Set the peer verification mode.
BOOST_ASIO_DECL boost::system::error_code set_verify_mode(
verify_mode v, boost::system::error_code& ec);
// Set the peer verification depth.
BOOST_ASIO_DECL boost::system::error_code set_verify_depth(
int depth, boost::system::error_code& ec);
// Set a peer certificate verification callback.
BOOST_ASIO_DECL boost::system::error_code set_verify_callback(
verify_callback_base* callback, boost::system::error_code& ec);
// Perform an SSL handshake using either SSL_connect (client-side) or
// SSL_accept (server-side).
BOOST_ASIO_DECL want handshake(
stream_base::handshake_type type, boost::system::error_code& ec);
// Perform a graceful shutdown of the SSL session.
BOOST_ASIO_DECL want shutdown(boost::system::error_code& ec);
// Write bytes to the SSL session.
BOOST_ASIO_DECL want write(const boost::asio::const_buffer& data,
boost::system::error_code& ec, std::size_t& bytes_transferred);
// Read bytes from the SSL session.
BOOST_ASIO_DECL want read(const boost::asio::mutable_buffer& data,
boost::system::error_code& ec, std::size_t& bytes_transferred);
// Get output data to be written to the transport.
BOOST_ASIO_DECL boost::asio::mutable_buffer get_output(
const boost::asio::mutable_buffer& data);
// Put input data that was read from the transport.
BOOST_ASIO_DECL boost::asio::const_buffer put_input(
const boost::asio::const_buffer& data);
// Map an error::eof code returned by the underlying transport according to
// the type and state of the SSL session. Returns a const reference to the
// error code object, suitable for passing to a completion handler.
BOOST_ASIO_DECL const boost::system::error_code& map_error_code(
boost::system::error_code& ec) const;
private:
// Disallow copying and assignment.
engine(const engine&);
engine& operator=(const engine&);
// Callback used when the SSL implementation wants to verify a certificate.
BOOST_ASIO_DECL static int verify_callback_function(
int preverified, X509_STORE_CTX* ctx);
#if (OPENSSL_VERSION_NUMBER < 0x10000000L)
// The SSL_accept function may not be thread safe. This mutex is used to
// protect all calls to the SSL_accept function.
BOOST_ASIO_DECL static boost::asio::detail::static_mutex& accept_mutex();
#endif // (OPENSSL_VERSION_NUMBER < 0x10000000L)
// Perform one operation. Returns >= 0 on success or error, want_read if the
// operation needs more input, or want_write if it needs to write some output
// before the operation can complete.
BOOST_ASIO_DECL want perform(int (engine::* op)(void*, std::size_t),
void* data, std::size_t length, boost::system::error_code& ec,
std::size_t* bytes_transferred);
// Adapt the SSL_accept function to the signature needed for perform().
BOOST_ASIO_DECL int do_accept(void*, std::size_t);
// Adapt the SSL_connect function to the signature needed for perform().
BOOST_ASIO_DECL int do_connect(void*, std::size_t);
// Adapt the SSL_shutdown function to the signature needed for perform().
BOOST_ASIO_DECL int do_shutdown(void*, std::size_t);
// Adapt the SSL_read function to the signature needed for perform().
BOOST_ASIO_DECL int do_read(void* data, std::size_t length);
// Adapt the SSL_write function to the signature needed for perform().
BOOST_ASIO_DECL int do_write(void* data, std::size_t length);
SSL* ssl_;
BIO* ext_bio_;
};
} // namespace detail
} // namespace ssl
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#if defined(BOOST_ASIO_HEADER_ONLY)
# include <boost/asio/ssl/detail/impl/engine.ipp>
#endif // defined(BOOST_ASIO_HEADER_ONLY)
#endif // BOOST_ASIO_SSL_DETAIL_ENGINE_HPP