/**
 * \file xtea.h
 *
 *  Copyright (C) 2009  Paul Bakker <polarssl_maintainer at polarssl dot org>
 *
 *  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 names of PolarSSL or XySSL 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 POLARSSL_XTEA_H
#define POLARSSL_XTEA_H

#define XTEA_ENCRYPT     1
#define XTEA_DECRYPT     0


/**
 * \brief          XTEA context structure
 */
typedef struct
{
    unsigned long k[4];       /*!< key */
}
xtea_context;

#ifdef __cplusplus
extern "C" {
#endif

/**
 * \brief          XTEA key schedule
 *
 * \param ctx      XTEA context to be initialized
 * \param key      the secret key
 */
void xtea_setup( xtea_context *ctx, unsigned char key[16] );

/**
 * \brief          XTEA cipher function
 *
 * \param ctx      XTEA context
 * \param mode     XTEA_ENCRYPT or XTEA_DECRYPT
 * \param input    8-byte input block
 * \param output   8-byte output block
 */
void xtea_crypt( xtea_context *ctx,
		 int mode,
		 unsigned char input[8],
		 unsigned char output[8] );

/*
 * \brief          Checkup routine
 *
 * \return         0 if successful, or 1 if the test failed
 */
int xtea_self_test( int verbose );

#ifdef __cplusplus
}
#endif

#endif /* xtea.h */