//
// openssl_context_service.hpp
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2005 Voipster / Indrek dot Juhani at voipster dot com
// Copyright (c) 2005 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_OPENSSL_CONTEXT_SERVICE_HPP
#define BOOST_ASIO_SSL_DETAIL_OPENSSL_CONTEXT_SERVICE_HPP

#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)

#include <boost/asio/detail/push_options.hpp>

#include <boost/asio/detail/push_options.hpp>
#include <string>
#include <boost/asio/detail/pop_options.hpp>

#include <boost/asio/error.hpp>
#include <boost/asio/io_service.hpp>
#include <boost/asio/ssl/context_base.hpp>
#include <boost/asio/ssl/detail/openssl_init.hpp>
#include <boost/asio/ssl/detail/openssl_types.hpp>

namespace boost {
namespace asio {
namespace ssl {
namespace detail {

class openssl_context_service
  : public boost::asio::io_service::service
{
public:
  // The native type of the context.
  typedef ::SSL_CTX* impl_type;

  // Constructor.
  openssl_context_service(boost::asio::io_service& io_service)
    : boost::asio::io_service::service(io_service)
  {
  }

  // Destroy all user-defined handler objects owned by the service.
  void shutdown_service()
  {
  }

  // Return a null context implementation.
  static impl_type null()
  {
    return 0;
  }

  // Create a new context implementation.
  void create(impl_type& impl, context_base::method m)
  {
    ::SSL_METHOD* ssl_method = 0;
    switch (m)
    {
    case context_base::sslv2:
      ssl_method = ::SSLv2_method();
      break;
    case context_base::sslv2_client:
      ssl_method = ::SSLv2_client_method();
      break;
    case context_base::sslv2_server:
      ssl_method = ::SSLv2_server_method();
      break;
    case context_base::sslv3:
      ssl_method = ::SSLv3_method();
      break;
    case context_base::sslv3_client:
      ssl_method = ::SSLv3_client_method();
      break;
    case context_base::sslv3_server:
      ssl_method = ::SSLv3_server_method();
      break;
    case context_base::tlsv1:
      ssl_method = ::TLSv1_method();
      break;
    case context_base::tlsv1_client:
      ssl_method = ::TLSv1_client_method();
      break;
    case context_base::tlsv1_server:
      ssl_method = ::TLSv1_server_method();
      break;
    case context_base::sslv23:
      ssl_method = ::SSLv23_method();
      break;
    case context_base::sslv23_client:
      ssl_method = ::SSLv23_client_method();
      break;
    case context_base::sslv23_server:
      ssl_method = ::SSLv23_server_method();
      break;
    default:
      break;
    }
    impl = ::SSL_CTX_new(ssl_method);
  }

  // Destroy a context implementation.
  void destroy(impl_type& impl)
  {
    if (impl != null())
    {
      ::SSL_CTX_free(impl);
      impl = null();
    }
  }

  // Set options on the context.
  template <typename Error_Handler>
  void set_options(impl_type& impl, context_base::options o,
      Error_Handler error_handler)
  {
    ::SSL_CTX_set_options(impl, o);

    boost::asio::error e;
    error_handler(e);
  }

  // Set peer verification mode.
  template <typename Error_Handler>
  void set_verify_mode(impl_type& impl, context_base::verify_mode v,
      Error_Handler error_handler)
  {
    ::SSL_CTX_set_verify(impl, v, 0);

    boost::asio::error e;
    error_handler(e);
  }

  // Load a certification authority file for performing verification.
  template <typename Error_Handler>
  void load_verify_file(impl_type& impl, const std::string& filename,
      Error_Handler error_handler)
  {
    if (::SSL_CTX_load_verify_locations(impl, filename.c_str(), 0) != 1)
    {
      boost::asio::error e(boost::asio::error::invalid_argument);
      error_handler(e);
      return;
    }

    boost::asio::error e;
    error_handler(e);
  }

  // Add a directory containing certification authority files to be used for
  // performing verification.
  template <typename Error_Handler>
  void add_verify_path(impl_type& impl, const std::string& path,
      Error_Handler error_handler)
  {
    if (::SSL_CTX_load_verify_locations(impl, 0, path.c_str()) != 1)
    {
      boost::asio::error e(boost::asio::error::invalid_argument);
      error_handler(e);
      return;
    }

    boost::asio::error e;
    error_handler(e);
  }

  // Use a certificate from a file.
  template <typename Error_Handler>
  void use_certificate_file(impl_type& impl, const std::string& filename,
      context_base::file_format format, Error_Handler error_handler)
  {
    int file_type;
    switch (format)
    {
    case context_base::asn1:
      file_type = SSL_FILETYPE_ASN1;
      break;
    case context_base::pem:
      file_type = SSL_FILETYPE_PEM;
      break;
    default:
      {
        boost::asio::error e(boost::asio::error::invalid_argument);
        error_handler(e);
        return;
      }
    }

    if (::SSL_CTX_use_certificate_file(impl, filename.c_str(), file_type) != 1)
    {
      boost::asio::error e(boost::asio::error::invalid_argument);
      error_handler(e);
      return;
    }

    boost::asio::error e;
    error_handler(e);
  }

  // Use a certificate chain from a file.
  template <typename Error_Handler>
  void use_certificate_chain_file(impl_type& impl, const std::string& filename,
      Error_Handler error_handler)
  {
    if (::SSL_CTX_use_certificate_chain_file(impl, filename.c_str()) != 1)
    {
      boost::asio::error e(boost::asio::error::invalid_argument);
      error_handler(e);
      return;
    }

    boost::asio::error e;
    error_handler(e);
  }

  // Use a private key from a file.
  template <typename Error_Handler>
  void use_private_key_file(impl_type& impl, const std::string& filename,
      context_base::file_format format, Error_Handler error_handler)
  {
    int file_type;
    switch (format)
    {
    case context_base::asn1:
      file_type = SSL_FILETYPE_ASN1;
      break;
    case context_base::pem:
      file_type = SSL_FILETYPE_PEM;
      break;
    default:
      {
        boost::asio::error e(boost::asio::error::invalid_argument);
        error_handler(e);
        return;
      }
    }

    if (::SSL_CTX_use_PrivateKey_file(impl, filename.c_str(), file_type) != 1)
    {
      boost::asio::error e(boost::asio::error::invalid_argument);
      error_handler(e);
      return;
    }

    boost::asio::error e;
    error_handler(e);
  }

  // Use an RSA private key from a file.
  template <typename Error_Handler>
  void use_rsa_private_key_file(impl_type& impl, const std::string& filename,
      context_base::file_format format, Error_Handler error_handler)
  {
    int file_type;
    switch (format)
    {
    case context_base::asn1:
      file_type = SSL_FILETYPE_ASN1;
      break;
    case context_base::pem:
      file_type = SSL_FILETYPE_PEM;
      break;
    default:
      {
        boost::asio::error e(boost::asio::error::invalid_argument);
        error_handler(e);
        return;
      }
    }

    if (::SSL_CTX_use_RSAPrivateKey_file(
          impl, filename.c_str(), file_type) != 1)
    {
      boost::asio::error e(boost::asio::error::invalid_argument);
      error_handler(e);
      return;
    }

    boost::asio::error e;
    error_handler(e);
  }

  // Use the specified file to obtain the temporary Diffie-Hellman parameters.
  template <typename Error_Handler>
  void use_tmp_dh_file(impl_type& impl, const std::string& filename,
      Error_Handler error_handler)
  {
    ::BIO* bio = ::BIO_new_file(filename.c_str(), "r");
    if (!bio)
    {
      boost::asio::error e(boost::asio::error::invalid_argument);
      error_handler(e);
      return;
    }

    ::DH* dh = ::PEM_read_bio_DHparams(bio, 0, 0, 0);
    if (!dh)
    {
      ::BIO_free(bio);
      boost::asio::error e(boost::asio::error::invalid_argument);
      error_handler(e);
      return;
    }

    ::BIO_free(bio);
    int result = ::SSL_CTX_set_tmp_dh(impl, dh);
    if (result != 1)
    {
      ::DH_free(dh);
      boost::asio::error e(boost::asio::error::invalid_argument);
      error_handler(e);
      return;
    }

    boost::asio::error e;
    error_handler(e);
  }

private:
  // Ensure openssl is initialised.
  openssl_init<> init_;
};

} // namespace detail
} // namespace ssl
} // namespace asio
} // namespace boost

#include <boost/asio/detail/pop_options.hpp>

#endif // BOOST_ASIO_SSL_DETAIL_OPENSSL_CONTEXT_SERVICE_HPP