/* * OpenVPN -- An application to securely tunnel IP networks * over a single TCP/UDP port, with support for SSL/TLS-based * session authentication and key exchange, * packet encryption, packet authentication, and * packet compression. * * Copyright (C) 2002-2010 OpenVPN Technologies, Inc. <sales@openvpn.net> * Copyright (C) 2010 Fox Crypto B.V. <openvpn@fox-it.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 * as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program (see the file COPYING included with this * distribution); if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /** * @file Control Channel SSL library backend module */ #ifndef SSL_BACKEND_H_ #define SSL_BACKEND_H_ #include "buffer.h" #ifdef USE_OPENSSL #include "ssl_openssl.h" #endif /* * * Functions implemented in ssl.c for use by the backend SSL library * */ /* * * Functions used in ssl.c which must be implemented by the backend SSL library * */ /** * Perform any static initialisation necessary by the library. * Called on OpenVPN initialisation */ void tls_init_lib(); /** * Free any global SSL library-specific data structures. */ void tls_free_lib(); /** * Clear the underlying SSL library's error state. */ void tls_clear_error(); /* * Show the TLS ciphers that are available for us to use in the OpenSSL * library. */ void show_available_tls_ciphers (); /* * The OpenSSL library has a notion of preference in TLS ciphers. Higher * preference == more secure. Return the highest preference cipher. */ void get_highest_preference_tls_cipher (char *buf, int size); #endif /* SSL_BACKEND_H_ */