/**
* \file aes.h
*
* \brief AES block cipher
*
* 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, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef POLARSSL_AES_H
#define POLARSSL_AES_H
#include <string.h>
#ifdef _MSC_VER
#include <basetsd.h>
typedef UINT32 uint32_t;
#else
#include <inttypes.h>
#endif
#define AES_ENCRYPT 1
#define AES_DECRYPT 0
#define POLARSSL_ERR_AES_INVALID_KEY_LENGTH -0x0020 /**< Invalid key length. */
#define POLARSSL_ERR_AES_INVALID_INPUT_LENGTH -0x0022 /**< Invalid data input length. */
/**
* \brief AES context structure
*/
typedef struct
{
int nr; /*!< number of rounds */
uint32_t *rk; /*!< AES round keys */
uint32_t buf[68]; /*!< unaligned data */
}
aes_context;
#ifdef __cplusplus
extern "C" {
#endif
/**
* \brief AES key schedule (encryption)
*
* \param ctx AES context to be initialized
* \param key encryption key
* \param keysize must be 128, 192 or 256
*
* \return 0 if successful, or POLARSSL_ERR_AES_INVALID_KEY_LENGTH
*/
int aes_setkey_enc( aes_context *ctx, const unsigned char *key, unsigned int keysize );
/**
* \brief AES key schedule (decryption)
*
* \param ctx AES context to be initialized
* \param key decryption key
* \param keysize must be 128, 192 or 256
*
* \return 0 if successful, or POLARSSL_ERR_AES_INVALID_KEY_LENGTH
*/
int aes_setkey_dec( aes_context *ctx, const unsigned char *key, unsigned int keysize );
/**
* \brief AES-ECB block encryption/decryption
*
* \param ctx AES context
* \param mode AES_ENCRYPT or AES_DECRYPT
* \param input 16-byte input block
* \param output 16-byte output block
*
* \return 0 if successful
*/
int aes_crypt_ecb( aes_context *ctx,
int mode,
const unsigned char input[16],
unsigned char output[16] );
/**
* \brief AES-CBC buffer encryption/decryption
* Length should be a multiple of the block
* size (16 bytes)
*
* \param ctx AES context
* \param mode AES_ENCRYPT or AES_DECRYPT
* \param length length of the input data
* \param iv initialization vector (updated after use)
* \param input buffer holding the input data
* \param output buffer holding the output data
*
* \return 0 if successful, or POLARSSL_ERR_AES_INVALID_INPUT_LENGTH
*/
int aes_crypt_cbc( aes_context *ctx,
int mode,
size_t length,
unsigned char iv[16],
const unsigned char *input,
unsigned char *output );
/**
* \brief AES-CFB128 buffer encryption/decryption.
*
* Note: Due to the nature of CFB you should use the same key schedule for
* both encryption and decryption. So a context initialized with
* aes_setkey_enc() for both AES_ENCRYPT and AES_DECRYPT.
*
* both
* \param ctx AES context
* \param mode AES_ENCRYPT or AES_DECRYPT
* \param length length of the input data
* \param iv_off offset in IV (updated after use)
* \param iv initialization vector (updated after use)
* \param input buffer holding the input data
* \param output buffer holding the output data
*
* \return 0 if successful
*/
int aes_crypt_cfb128( aes_context *ctx,
int mode,
size_t length,
size_t *iv_off,
unsigned char iv[16],
const unsigned char *input,
unsigned char *output );
/**
* \brief AES-CTR buffer encryption/decryption
*
* Warning: You have to keep the maximum use of your counter in mind!
*
* Note: Due to the nature of CTR you should use the same key schedule for
* both encryption and decryption. So a context initialized with
* aes_setkey_enc() for both AES_ENCRYPT and AES_DECRYPT.
*
* \param length The length of the data
* \param nc_off The offset in the current stream_block (for resuming
* within current cipher stream). The offset pointer to
* should be 0 at the start of a stream.
* \param nonce_counter The 128-bit nonce and counter.
* \param stream_block The saved stream-block for resuming. Is overwritten
* by the function.
* \param input The input data stream
* \param output The output data stream
*
* \return 0 if successful
*/
int aes_crypt_ctr( aes_context *ctx,
size_t length,
size_t *nc_off,
unsigned char nonce_counter[16],
unsigned char stream_block[16],
const unsigned char *input,
unsigned char *output );
/**
* \brief Checkup routine
*
* \return 0 if successful, or 1 if the test failed
*/
int aes_self_test( int verbose );
#ifdef __cplusplus
}
#endif
#endif /* aes.h */