/*
 *  SHA-224 and SHA-256 cryptographic hash function
 *
 *  Copyright (C) 2006-2010, Brainspark B.V.
 *
 *  This file is part of PolarSSL (http://www.polarssl.org)
 *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
 *
 *  All rights reserved.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef SHA2_H
#define SHA2_H

#include <string.h>

/**
 * \brief          SHA-256 context structure
 */
typedef struct
{
    unsigned long total[2];     /*!< number of bytes processed  */
    unsigned long state[8];     /*!< intermediate digest state  */
    unsigned char buffer[64];   /*!< data block being processed */

    int is224;                  /*!< 0 => SHA-256, else SHA-224 */
}
sha2_context;

/**
 * \brief          Output = SHA-256( input buffer )
 *
 * \param input    buffer holding the  data
 * \param ilen     length of the input data
 * \param output   SHA-224/256 checksum result
 * \param is224    0 = use SHA256, 1 = use SHA224
 */
void sha2( const unsigned char *input, size_t ilen,
           unsigned char output[32], int is224 );

/**
 * \brief          Output = SHA-256( file contents )
 *
 * \param path     input file name
 * \param output   SHA-224/256 checksum result
 * \param is224    0 = use SHA256, 1 = use SHA224
 *
 * \return         0 if successful, 1 if fopen failed,
 *                 or 2 if fread failed
 */
int sha2_file( const char *path, unsigned char output[32], int is224 );

#endif /* sha2.h */