/*
 *  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 Data Channel Cryptography SSL library-specific backend interface
 */

#ifndef CRYPTO_BACKEND_H_
#define CRYPTO_BACKEND_H_

#include "config.h"

#ifdef USE_OPENSSL
#include "crypto_openssl.h"
#endif

#include "basic.h"

/*
 *
 * Random number functions, used in cases where we want
 * reasonably strong cryptographic random number generation
 * without depleting our entropy pool.  Used for random
 * IV values and a number of other miscellaneous tasks.
 *
 */

/**
 * Wrapper for secure random number generator. Retrieves len bytes of random
 * data, and places it in output.
 *
 * @param output	Output buffer
 * @param len		Length of the output buffer, in bytes
 *
 * @return 		\c 1 on success, \c 0 on failure
 */
int rand_bytes (uint8_t *output, int len);

#endif /* CRYPTO_BACKEND_H_ */