text: /*
  
  Copyright (c) 2008-2018, Arvid Norberg
  All rights reserved.
  
  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions
  are met:
  
      * Redistributions of source code must retain the above copyright
        notice, this list of conditions and the following disclaimer.
      * Redistributions in binary form must reproduce the above copyright
        notice, this list of conditions and the following disclaimer in
        the documentation and/or other materials provided with the distribution.
      * Neither the name of the author nor the names of its
        contributors may be used to endorse or promote products derived
        from this software without specific prior written permission.
  
  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  POSSIBILITY OF SUCH DAMAGE.
  
  */
  
  #ifndef TORRENT_SSL_STREAM_HPP_INCLUDED
  #define TORRENT_SSL_STREAM_HPP_INCLUDED
  
  #ifdef TORRENT_USE_OPENSSL
  
  #include "libtorrent/socket.hpp"
  #include "libtorrent/error_code.hpp"
  #include "libtorrent/io_context.hpp"
  #include "libtorrent/aux_/openssl.hpp"
  
  #include <functional>
  
  #include "libtorrent/aux_/disable_warnings_push.hpp"
  #include <boost/asio/ssl.hpp>
  #if defined TORRENT_BUILD_SIMULATOR
  #include "simulator/simulator.hpp"
  #endif
  #include "libtorrent/aux_/disable_warnings_pop.hpp"
  
  namespace libtorrent {
  namespace ssl {
  
  #if defined TORRENT_BUILD_SIMULATOR
  	using sim::asio::ssl::context;
  	using sim::asio::ssl::stream_base;
  	using sim::asio::ssl::stream;
  #else
  	using boost::asio::ssl::context;
  	using boost::asio::ssl::stream_base;
  	using boost::asio::ssl::stream;
  #endif
  }
  
  template <class Stream>
  class ssl_stream
  {
  public:
  
  	explicit ssl_stream(io_context& io_context, ssl::context& ctx)
  		: m_sock(io_context, ctx)
  	{
  	}
  
  	using sock_type = typename boost::asio::ssl::stream<Stream>;
  	using next_layer_type = typename sock_type::next_layer_type;
  	using lowest_layer_type = typename Stream::lowest_layer_type;
  	using endpoint_type = typename Stream::endpoint_type;
  	using protocol_type = typename Stream::protocol_type;
  	using executor_type = typename sock_type::executor_type;
  	executor_type get_executor() { return m_sock.get_executor(); }
  
  	void set_host_name(std::string const& name)
  	{
  		aux::openssl_set_tlsext_hostname(m_sock.native_handle(), name.c_str());
  	}
  
  	template <class T>
  	void set_verify_callback(T const& fun, error_code& ec)
  	{ m_sock.set_verify_callback(fun, ec); }
  
  	SSL* native_handle() { return m_sock.native_handle(); }
  
  	using handler_type = std::function<void(error_code const&)>;
  
  	template <class Handler>
  	void async_connect(endpoint_type const& endpoint, Handler const& handler)
  	{
  		// the connect is split up in the following steps:
  		// 1. connect to peer
  		// 2. perform SSL client handshake
  
  		// to avoid unnecessary copying of the handler,
  		// store it in a shared_ptr
  		auto h = std::make_shared<handler_type>(handler);
  
  		using std::placeholders::_1;
  		m_sock.next_layer().async_connect(endpoint
  			, std::bind(&ssl_stream::connected, this, _1, h));
  	}
  
  	template <class Handler>
  	void async_accept_handshake(Handler const& handler)
  	{
  		// this is used for accepting SSL connections
  		auto h = std::make_shared<handler_type>(handler);
  		using std::placeholders::_1;
  		m_sock.async_handshake(ssl::stream_base::server
  			, std::bind(&ssl_stream::handshake, this, _1, h));
  	}
  
  	void accept_handshake(error_code& ec)
  	{
  		// this is used for accepting SSL connections
  		m_sock.handshake(ssl::stream_base::server, ec);
  	}
  
  	template <class Handler>
  	void async_shutdown(Handler const& handler)
  	{
  		error_code ec;
  		m_sock.next_layer().cancel(ec);
  		m_sock.async_shutdown(handler);
  	}
  
  	void shutdown(error_code& ec)
  	{
  		m_sock.shutdown(ec);
  	}
  
  	template <class Mutable_Buffers, class Handler>
  	void async_read_some(Mutable_Buffers const& buffers, Handler const& handler)
  	{
  		m_sock.async_read_some(buffers, handler);
  	}
  
  	template <class Mutable_Buffers>
  	std::size_t read_some(Mutable_Buffers const& buffers, error_code& ec)
  	{
  		return m_sock.read_some(buffers, ec);
  	}
  
  #ifndef BOOST_NO_EXCEPTIONS
  	template <class SettableSocketOption>
  	void set_option(SettableSocketOption const& opt)
  	{
  		m_sock.next_layer().set_option(opt);
  	}
  #endif
  
  	template <class SettableSocketOption>
  	void set_option(SettableSocketOption const& opt, error_code& ec)
  	{
  		m_sock.next_layer().set_option(opt, ec);
  	}
  
  #ifndef BOOST_NO_EXCEPTIONS
  	template <class GettableSocketOption>
  	void get_option(GettableSocketOption& opt)
  	{
  		m_sock.next_layer().get_option(opt);
  	}
  #endif
  
  	template <class GettableSocketOption>
  	void get_option(GettableSocketOption& opt, error_code& ec)
  	{
  		m_sock.next_layer().get_option(opt, ec);
  	}
  
  #ifndef BOOST_NO_EXCEPTIONS
  	template <class Mutable_Buffers>
  	std::size_t read_some(Mutable_Buffers const& buffers)
  	{
  		return m_sock.read_some(buffers);
  	}
  
  	template <class IO_Control_Command>
  	void io_control(IO_Control_Command& ioc)
  	{
  		m_sock.next_layer().io_control(ioc);
  	}
  #endif
  
  	template <class IO_Control_Command>
  	void io_control(IO_Control_Command& ioc, error_code& ec)
  	{
  		m_sock.next_layer().io_control(ioc, ec);
  	}
  
  #ifndef BOOST_NO_EXCEPTIONS
  	void non_blocking(bool b) { m_sock.next_layer().non_blocking(b); }
  #endif
  
  	void non_blocking(bool b, error_code& ec)
  	{ m_sock.next_layer().non_blocking(b, ec); }
  
  	template <class Const_Buffers, class Handler>
  	void async_write_some(Const_Buffers const& buffers, Handler const& handler)
  	{
  		m_sock.async_write_some(buffers, handler);
  	}
  
  	template <class Const_Buffers>
  	std::size_t write_some(Const_Buffers const& buffers, error_code& ec)
  	{
  		return m_sock.write_some(buffers, ec);
  	}
  
  	// the SSL stream may cache 17 kiB internally, and there's no way of
  	// asking how large its buffer is. 17 kiB isn't very much though, so it
  	// seems fine to potentially over-estimate the number of bytes available.
  #ifndef BOOST_NO_EXCEPTIONS
  	std::size_t available() const
  	{ return 17 * 1024 + const_cast<sock_type&>(m_sock).next_layer().available(); }
  #endif
  
  	std::size_t available(error_code& ec) const
  	{ return 17 * 1024 + const_cast<sock_type&>(m_sock).next_layer().available(ec); }
  
  #ifndef BOOST_NO_EXCEPTIONS
  	void bind(endpoint_type const& endpoint)
  	{
  		m_sock.next_layer().bind(endpoint);
  	}
  #endif
  
  	void bind(endpoint_type const& endpoint, error_code& ec)
  	{
  		m_sock.next_layer().bind(endpoint, ec);
  	}
  
  #ifndef BOOST_NO_EXCEPTIONS
  	void open(protocol_type const& p)
  	{
  		m_sock.next_layer().open(p);
  	}
  #endif
  
  	void open(protocol_type const& p, error_code& ec)
  	{
  		m_sock.next_layer().open(p, ec);
  	}
  
  	bool is_open() const
  	{
  		return const_cast<sock_type&>(m_sock).next_layer().is_open();
  	}
  
  #ifndef BOOST_NO_EXCEPTIONS
  	void close()
  	{
  		m_sock.next_layer().close();
  	}
  #endif
  
  	void close(error_code& ec)
  	{
  		m_sock.next_layer().close(ec);
  	}
  
  #ifndef BOOST_NO_EXCEPTIONS
  	endpoint_type remote_endpoint() const
  	{
  		return const_cast<sock_type&>(m_sock).next_layer().remote_endpoint();
  	}
  #endif
  
  	endpoint_type remote_endpoint(error_code& ec) const
  	{
  		return const_cast<sock_type&>(m_sock).next_layer().remote_endpoint(ec);
  	}
  
  #ifndef BOOST_NO_EXCEPTIONS
  	endpoint_type local_endpoint() const
  	{
  		return const_cast<sock_type&>(m_sock).next_layer().local_endpoint();
  	}
  #endif
  
  	endpoint_type local_endpoint(error_code& ec) const
  	{
  		return const_cast<sock_type&>(m_sock).next_layer().local_endpoint(ec);
  	}
  
  	lowest_layer_type& lowest_layer()
  	{
  		return m_sock.lowest_layer();
  	}
  
  	next_layer_type& next_layer()
  	{
  		return m_sock.next_layer();
  	}
  
  private:
  
  	void connected(error_code const& e, std::shared_ptr<handler_type> h)
  	{
  		if (e)
  		{
  			(*h)(e);
  			return;
  		}
  
  		using std::placeholders::_1;
  		m_sock.async_handshake(ssl::stream_base::client
  			, std::bind(&ssl_stream::handshake, this, _1, h));
  	}
  
  	void handshake(error_code const& e, std::shared_ptr<handler_type> h)
  	{
  		(*h)(e);
  	}
  
  	ssl::stream<Stream> m_sock;
  };
  
  }
  
  #endif // TORRENT_USE_OPENSSL
  
  #endif
  