text: //
  // ssl/context.hpp
  // ~~~~~~~~~~~~~~~
  //
  // Copyright (c) 2003-2015 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 ASIO_SSL_CONTEXT_HPP
  #define ASIO_SSL_CONTEXT_HPP
  
  #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  # pragma once
  #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  
  #include "asio/detail/config.hpp"
  
  #if defined(ASIO_ENABLE_OLD_SSL)
  # include "asio/ssl/basic_context.hpp"
  # include "asio/ssl/context_service.hpp"
  #else // defined(ASIO_ENABLE_OLD_SSL)
  # include <string>
  # include "asio/buffer.hpp"
  # include "asio/io_service.hpp"
  # include "asio/ssl/context_base.hpp"
  # include "asio/ssl/detail/openssl_types.hpp"
  # include "asio/ssl/detail/openssl_init.hpp"
  # include "asio/ssl/detail/password_callback.hpp"
  # include "asio/ssl/detail/verify_callback.hpp"
  # include "asio/ssl/verify_mode.hpp"
  #endif // defined(ASIO_ENABLE_OLD_SSL)
  
  #include "asio/detail/push_options.hpp"
  
  namespace asio {
  namespace ssl {
  
  #if defined(ASIO_ENABLE_OLD_SSL)
  
  /// Typedef for the typical usage of context.
  typedef basic_context<context_service> context;
  
  #else // defined(ASIO_ENABLE_OLD_SSL)
  
  class context
    : public context_base,
      private noncopyable
  {
  public:
    /// The native handle type of the SSL context.
    typedef SSL_CTX* native_handle_type;
  
    /// (Deprecated: Use native_handle_type.) The native type of the SSL context.
    typedef SSL_CTX* impl_type;
  
    /// Constructor.
    ASIO_DECL explicit context(method m);
  
    /// Deprecated constructor taking a reference to an io_service object.
    ASIO_DECL context(asio::io_service&, method m);
  
  #if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
    /// Move-construct a context from another.
    /**
     * This constructor moves an SSL context from one object to another.
     *
     * @param other The other context object from which the move will occur.
     *
     * @note Following the move, the following operations only are valid for the
     * moved-from object:
     * @li Destruction.
     * @li As a target for move-assignment.
     */
    ASIO_DECL context(context&& other);
  
    /// Move-assign a context from another.
    /**
     * This assignment operator moves an SSL context from one object to another.
     *
     * @param other The other context object from which the move will occur.
     *
     * @note Following the move, the following operations only are valid for the
     * moved-from object:
     * @li Destruction.
     * @li As a target for move-assignment.
     */
    ASIO_DECL context& operator=(context&& other);
  #endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
  
    /// Destructor.
    ASIO_DECL ~context();
  
    /// Get the underlying implementation in the native type.
    /**
     * This function may be used to obtain the underlying implementation of the
     * context. This is intended to allow access to context functionality that is
     * not otherwise provided.
     */
    ASIO_DECL native_handle_type native_handle();
  
    /// (Deprecated: Use native_handle().) Get the underlying implementation in
    /// the native type.
    /**
     * This function may be used to obtain the underlying implementation of the
     * context. This is intended to allow access to context functionality that is
     * not otherwise provided.
     */
    ASIO_DECL impl_type impl();
  
    /// Clear options on the context.
    /**
     * This function may be used to configure the SSL options used by the context.
     *
     * @param o A bitmask of options. The available option values are defined in
     * the context_base class. The specified options, if currently enabled on the
     * context, are cleared.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_clear_options.
     */
    ASIO_DECL void clear_options(options o);
  
    /// Clear options on the context.
    /**
     * This function may be used to configure the SSL options used by the context.
     *
     * @param o A bitmask of options. The available option values are defined in
     * the context_base class. The specified options, if currently enabled on the
     * context, are cleared.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_clear_options.
     */
    ASIO_DECL asio::error_code clear_options(options o,
        asio::error_code& ec);
  
    /// Set options on the context.
    /**
     * This function may be used to configure the SSL options used by the context.
     *
     * @param o A bitmask of options. The available option values are defined in
     * the context_base class. The options are bitwise-ored with any existing
     * value for the options.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_set_options.
     */
    ASIO_DECL void set_options(options o);
  
    /// Set options on the context.
    /**
     * This function may be used to configure the SSL options used by the context.
     *
     * @param o A bitmask of options. The available option values are defined in
     * the context_base class. The options are bitwise-ored with any existing
     * value for the options.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_set_options.
     */
    ASIO_DECL asio::error_code set_options(options o,
        asio::error_code& ec);
  
    /// Set the peer verification mode.
    /**
     * This function may be used to configure the peer verification mode used by
     * the context.
     *
     * @param v A bitmask of peer verification modes. See @ref verify_mode for
     * available values.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_set_verify.
     */
    ASIO_DECL void set_verify_mode(verify_mode v);
  
    /// Set the peer verification mode.
    /**
     * This function may be used to configure the peer verification mode used by
     * the context.
     *
     * @param v A bitmask of peer verification modes. See @ref verify_mode for
     * available values.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_set_verify.
     */
    ASIO_DECL asio::error_code set_verify_mode(
        verify_mode v, asio::error_code& ec);
  
    /// Set the peer verification depth.
    /**
     * This function may be used to configure the maximum verification depth
     * allowed by the context.
     *
     * @param depth Maximum depth for the certificate chain verification that
     * shall be allowed.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_set_verify_depth.
     */
    ASIO_DECL void set_verify_depth(int depth);
  
    /// Set the peer verification depth.
    /**
     * This function may be used to configure the maximum verification depth
     * allowed by the context.
     *
     * @param depth Maximum depth for the certificate chain verification that
     * shall be allowed.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_set_verify_depth.
     */
    ASIO_DECL asio::error_code set_verify_depth(
        int depth, asio::error_code& ec);
  
    /// Set the callback used to verify peer certificates.
    /**
     * This function is used to specify a callback function that will be called
     * by the implementation when it needs to verify a peer certificate.
     *
     * @param callback The function object to be used for verifying a certificate.
     * The function signature of the handler must be:
     * @code bool verify_callback(
     *   bool preverified, // True if the certificate passed pre-verification.
     *   verify_context& ctx // The peer certificate and other context.
     * ); @endcode
     * The return value of the callback is true if the certificate has passed
     * verification, false otherwise.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_set_verify.
     */
    template <typename VerifyCallback>
    void set_verify_callback(VerifyCallback callback);
  
    /// Set the callback used to verify peer certificates.
    /**
     * This function is used to specify a callback function that will be called
     * by the implementation when it needs to verify a peer certificate.
     *
     * @param callback The function object to be used for verifying a certificate.
     * The function signature of the handler must be:
     * @code bool verify_callback(
     *   bool preverified, // True if the certificate passed pre-verification.
     *   verify_context& ctx // The peer certificate and other context.
     * ); @endcode
     * The return value of the callback is true if the certificate has passed
     * verification, false otherwise.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_set_verify.
     */
    template <typename VerifyCallback>
    asio::error_code set_verify_callback(VerifyCallback callback,
        asio::error_code& ec);
  
    /// Load a certification authority file for performing verification.
    /**
     * This function is used to load one or more trusted certification authorities
     * from a file.
     *
     * @param filename The name of a file containing certification authority
     * certificates in PEM format.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_load_verify_locations.
     */
    ASIO_DECL void load_verify_file(const std::string& filename);
  
    /// Load a certification authority file for performing verification.
    /**
     * This function is used to load the certificates for one or more trusted
     * certification authorities from a file.
     *
     * @param filename The name of a file containing certification authority
     * certificates in PEM format.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_load_verify_locations.
     */
    ASIO_DECL asio::error_code load_verify_file(
        const std::string& filename, asio::error_code& ec);
  
    /// Add certification authority for performing verification.
    /**
     * This function is used to add one trusted certification authority
     * from a memory buffer.
     *
     * @param ca The buffer containing the certification authority certificate.
     * The certificate must use the PEM format.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_get_cert_store and @c X509_STORE_add_cert.
     */
    ASIO_DECL void add_certificate_authority(const const_buffer& ca);
  
    /// Add certification authority for performing verification.
    /**
     * This function is used to add one trusted certification authority
     * from a memory buffer.
     *
     * @param ca The buffer containing the certification authority certificate.
     * The certificate must use the PEM format.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_get_cert_store and @c X509_STORE_add_cert.
     */
    ASIO_DECL asio::error_code add_certificate_authority(
        const const_buffer& ca, asio::error_code& ec);
  
    /// Configures the context to use the default directories for finding
    /// certification authority certificates.
    /**
     * This function specifies that the context should use the default,
     * system-dependent directories for locating certification authority
     * certificates.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_set_default_verify_paths.
     */
    ASIO_DECL void set_default_verify_paths();
  
    /// Configures the context to use the default directories for finding
    /// certification authority certificates.
    /**
     * This function specifies that the context should use the default,
     * system-dependent directories for locating certification authority
     * certificates.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_set_default_verify_paths.
     */
    ASIO_DECL asio::error_code set_default_verify_paths(
        asio::error_code& ec);
  
    /// Add a directory containing certificate authority files to be used for
    /// performing verification.
    /**
     * This function is used to specify the name of a directory containing
     * certification authority certificates. Each file in the directory must
     * contain a single certificate. The files must be named using the subject
     * name's hash and an extension of ".0".
     *
     * @param path The name of a directory containing the certificates.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_load_verify_locations.
     */
    ASIO_DECL void add_verify_path(const std::string& path);
  
    /// Add a directory containing certificate authority files to be used for
    /// performing verification.
    /**
     * This function is used to specify the name of a directory containing
     * certification authority certificates. Each file in the directory must
     * contain a single certificate. The files must be named using the subject
     * name's hash and an extension of ".0".
     *
     * @param path The name of a directory containing the certificates.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_load_verify_locations.
     */
    ASIO_DECL asio::error_code add_verify_path(
        const std::string& path, asio::error_code& ec);
  
    /// Use a certificate from a memory buffer.
    /**
     * This function is used to load a certificate into the context from a buffer.
     *
     * @param certificate The buffer containing the certificate.
     *
     * @param format The certificate format (ASN.1 or PEM).
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_use_certificate or SSL_CTX_use_certificate_ASN1.
     */
    ASIO_DECL void use_certificate(
        const const_buffer& certificate, file_format format);
  
    /// Use a certificate from a memory buffer.
    /**
     * This function is used to load a certificate into the context from a buffer.
     *
     * @param certificate The buffer containing the certificate.
     *
     * @param format The certificate format (ASN.1 or PEM).
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_use_certificate or SSL_CTX_use_certificate_ASN1.
     */
    ASIO_DECL asio::error_code use_certificate(
        const const_buffer& certificate, file_format format,
        asio::error_code& ec);
  
    /// Use a certificate from a file.
    /**
     * This function is used to load a certificate into the context from a file.
     *
     * @param filename The name of the file containing the certificate.
     *
     * @param format The file format (ASN.1 or PEM).
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_use_certificate_file.
     */
    ASIO_DECL void use_certificate_file(
        const std::string& filename, file_format format);
  
    /// Use a certificate from a file.
    /**
     * This function is used to load a certificate into the context from a file.
     *
     * @param filename The name of the file containing the certificate.
     *
     * @param format The file format (ASN.1 or PEM).
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_use_certificate_file.
     */
    ASIO_DECL asio::error_code use_certificate_file(
        const std::string& filename, file_format format,
        asio::error_code& ec);
  
    /// Use a certificate chain from a memory buffer.
    /**
     * This function is used to load a certificate chain into the context from a
     * buffer.
     *
     * @param chain The buffer containing the certificate chain. The certificate
     * chain must use the PEM format.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_use_certificate and SSL_CTX_add_extra_chain_cert.
     */
    ASIO_DECL void use_certificate_chain(const const_buffer& chain);
  
    /// Use a certificate chain from a memory buffer.
    /**
     * This function is used to load a certificate chain into the context from a
     * buffer.
     *
     * @param chain The buffer containing the certificate chain. The certificate
     * chain must use the PEM format.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_use_certificate and SSL_CTX_add_extra_chain_cert.
     */
    ASIO_DECL asio::error_code use_certificate_chain(
        const const_buffer& chain, asio::error_code& ec);
  
    /// Use a certificate chain from a file.
    /**
     * This function is used to load a certificate chain into the context from a
     * file.
     *
     * @param filename The name of the file containing the certificate. The file
     * must use the PEM format.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_use_certificate_chain_file.
     */
    ASIO_DECL void use_certificate_chain_file(const std::string& filename);
  
    /// Use a certificate chain from a file.
    /**
     * This function is used to load a certificate chain into the context from a
     * file.
     *
     * @param filename The name of the file containing the certificate. The file
     * must use the PEM format.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_use_certificate_chain_file.
     */
    ASIO_DECL asio::error_code use_certificate_chain_file(
        const std::string& filename, asio::error_code& ec);
  
    /// Use a private key from a memory buffer.
    /**
     * This function is used to load a private key into the context from a buffer.
     *
     * @param private_key The buffer containing the private key.
     *
     * @param format The private key format (ASN.1 or PEM).
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_use_PrivateKey or SSL_CTX_use_PrivateKey_ASN1.
     */
    ASIO_DECL void use_private_key(
        const const_buffer& private_key, file_format format);
  
    /// Use a private key from a memory buffer.
    /**
     * This function is used to load a private key into the context from a buffer.
     *
     * @param private_key The buffer containing the private key.
     *
     * @param format The private key format (ASN.1 or PEM).
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_use_PrivateKey or SSL_CTX_use_PrivateKey_ASN1.
     */
    ASIO_DECL asio::error_code use_private_key(
        const const_buffer& private_key, file_format format,
        asio::error_code& ec);
  
    /// Use a private key from a file.
    /**
     * This function is used to load a private key into the context from a file.
     *
     * @param filename The name of the file containing the private key.
     *
     * @param format The file format (ASN.1 or PEM).
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_use_PrivateKey_file.
     */
    ASIO_DECL void use_private_key_file(
        const std::string& filename, file_format format);
  
    /// Use a private key from a file.
    /**
     * This function is used to load a private key into the context from a file.
     *
     * @param filename The name of the file containing the private key.
     *
     * @param format The file format (ASN.1 or PEM).
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_use_PrivateKey_file.
     */
    ASIO_DECL asio::error_code use_private_key_file(
        const std::string& filename, file_format format,
        asio::error_code& ec);
  
    /// Use an RSA private key from a memory buffer.
    /**
     * This function is used to load an RSA private key into the context from a
     * buffer.
     *
     * @param private_key The buffer containing the RSA private key.
     *
     * @param format The private key format (ASN.1 or PEM).
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_use_RSAPrivateKey or SSL_CTX_use_RSAPrivateKey_ASN1.
     */
    ASIO_DECL void use_rsa_private_key(
        const const_buffer& private_key, file_format format);
  
    /// Use an RSA private key from a memory buffer.
    /**
     * This function is used to load an RSA private key into the context from a
     * buffer.
     *
     * @param private_key The buffer containing the RSA private key.
     *
     * @param format The private key format (ASN.1 or PEM).
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_use_RSAPrivateKey or SSL_CTX_use_RSAPrivateKey_ASN1.
     */
    ASIO_DECL asio::error_code use_rsa_private_key(
        const const_buffer& private_key, file_format format,
        asio::error_code& ec);
  
    /// Use an RSA private key from a file.
    /**
     * This function is used to load an RSA private key into the context from a
     * file.
     *
     * @param filename The name of the file containing the RSA private key.
     *
     * @param format The file format (ASN.1 or PEM).
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_use_RSAPrivateKey_file.
     */
    ASIO_DECL void use_rsa_private_key_file(
        const std::string& filename, file_format format);
  
    /// Use an RSA private key from a file.
    /**
     * This function is used to load an RSA private key into the context from a
     * file.
     *
     * @param filename The name of the file containing the RSA private key.
     *
     * @param format The file format (ASN.1 or PEM).
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_use_RSAPrivateKey_file.
     */
    ASIO_DECL asio::error_code use_rsa_private_key_file(
        const std::string& filename, file_format format,
        asio::error_code& ec);
  
    /// Use the specified memory buffer to obtain the temporary Diffie-Hellman
    /// parameters.
    /**
     * This function is used to load Diffie-Hellman parameters into the context
     * from a buffer.
     *
     * @param dh The memory buffer containing the Diffie-Hellman parameters. The
     * buffer must use the PEM format.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_set_tmp_dh.
     */
    ASIO_DECL void use_tmp_dh(const const_buffer& dh);
  
    /// Use the specified memory buffer to obtain the temporary Diffie-Hellman
    /// parameters.
    /**
     * This function is used to load Diffie-Hellman parameters into the context
     * from a buffer.
     *
     * @param dh The memory buffer containing the Diffie-Hellman parameters. The
     * buffer must use the PEM format.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_set_tmp_dh.
     */
    ASIO_DECL asio::error_code use_tmp_dh(
        const const_buffer& dh, asio::error_code& ec);
  
    /// Use the specified file to obtain the temporary Diffie-Hellman parameters.
    /**
     * This function is used to load Diffie-Hellman parameters into the context
     * from a file.
     *
     * @param filename The name of the file containing the Diffie-Hellman
     * parameters. The file must use the PEM format.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_set_tmp_dh.
     */
    ASIO_DECL void use_tmp_dh_file(const std::string& filename);
  
    /// Use the specified file to obtain the temporary Diffie-Hellman parameters.
    /**
     * This function is used to load Diffie-Hellman parameters into the context
     * from a file.
     *
     * @param filename The name of the file containing the Diffie-Hellman
     * parameters. The file must use the PEM format.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_set_tmp_dh.
     */
    ASIO_DECL asio::error_code use_tmp_dh_file(
        const std::string& filename, asio::error_code& ec);
  
    /// Set the password callback.
    /**
     * This function is used to specify a callback function to obtain password
     * information about an encrypted key in PEM format.
     *
     * @param callback The function object to be used for obtaining the password.
     * The function signature of the handler must be:
     * @code std::string password_callback(
     *   std::size_t max_length,  // The maximum size for a password.
     *   password_purpose purpose // Whether password is for reading or writing.
     * ); @endcode
     * The return value of the callback is a string containing the password.
     *
     * @throws asio::system_error Thrown on failure.
     *
     * @note Calls @c SSL_CTX_set_default_passwd_cb.
     */
    template <typename PasswordCallback>
    void set_password_callback(PasswordCallback callback);
  
    /// Set the password callback.
    /**
     * This function is used to specify a callback function to obtain password
     * information about an encrypted key in PEM format.
     *
     * @param callback The function object to be used for obtaining the password.
     * The function signature of the handler must be:
     * @code std::string password_callback(
     *   std::size_t max_length,  // The maximum size for a password.
     *   password_purpose purpose // Whether password is for reading or writing.
     * ); @endcode
     * The return value of the callback is a string containing the password.
     *
     * @param ec Set to indicate what error occurred, if any.
     *
     * @note Calls @c SSL_CTX_set_default_passwd_cb.
     */
    template <typename PasswordCallback>
    asio::error_code set_password_callback(PasswordCallback callback,
        asio::error_code& ec);
  
  private:
    struct bio_cleanup;
    struct x509_cleanup;
    struct evp_pkey_cleanup;
    struct rsa_cleanup;
    struct dh_cleanup;
  
    // Helper function used to set a peer certificate verification callback.
    ASIO_DECL asio::error_code do_set_verify_callback(
        detail::verify_callback_base* callback, asio::error_code& ec);
  
    // Callback used when the SSL implementation wants to verify a certificate.
    ASIO_DECL static int verify_callback_function(
        int preverified, X509_STORE_CTX* ctx);
  
    // Helper function used to set a password callback.
    ASIO_DECL asio::error_code do_set_password_callback(
        detail::password_callback_base* callback, asio::error_code& ec);
  
    // Callback used when the SSL implementation wants a password.
    ASIO_DECL static int password_callback_function(
        char* buf, int size, int purpose, void* data);
  
    // Helper function to set the temporary Diffie-Hellman parameters from a BIO.
    ASIO_DECL asio::error_code do_use_tmp_dh(
        BIO* bio, asio::error_code& ec);
  
    // Helper function to make a BIO from a memory buffer.
    ASIO_DECL BIO* make_buffer_bio(const const_buffer& b);
  
    // The underlying native implementation.
    native_handle_type handle_;
  
    // Ensure openssl is initialised.
    asio::ssl::detail::openssl_init<> init_;
  };
  
  #endif // defined(ASIO_ENABLE_OLD_SSL)
  
  } // namespace ssl
  } // namespace asio
  
  #include "asio/detail/pop_options.hpp"
  
  #include "asio/ssl/impl/context.hpp"
  #if defined(ASIO_HEADER_ONLY)
  # include "asio/ssl/impl/context.ipp"
  #endif // defined(ASIO_HEADER_ONLY)
  
  #endif // ASIO_SSL_CONTEXT_HPP
  