tiny_aes.h

/**
 * \file aes.h
 *
 *  Based on TropicSSL: Copyright (C) 2017 Shanghai Real-Thread Technology Co., Ltd
 * 
 *  Based on XySSL: Copyright (C) 2006-2008  Christophe Devine
 *
 *  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 TINY_CRYPT_AES_H__
#define TINY_CRYPT_AES_H__

#define AES_ENCRYPT     1
#define AES_DECRYPT     0

/**
 * \brief          AES context structure
 */
typedef struct {
	int nr;			/*!<  number of rounds  */
	unsigned long *rk;	/*!<  AES round keys    */
	unsigned long buf[68];	/*!<  unaligned data    */
} tiny_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
	 */
	void tiny_aes_setkey_enc(tiny_aes_context * ctx, unsigned char *key, 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
	 */
	void tiny_aes_setkey_dec(tiny_aes_context * ctx, unsigned char *key, 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
	 */
	void tiny_aes_crypt_ecb(tiny_aes_context * ctx,
			   int mode,
			   unsigned char input[16], unsigned char output[16]);

	/**
	 * \brief          AES-CBC buffer encryption/decryption
	 *
	 * \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
	 */
	void tiny_aes_crypt_cbc(tiny_aes_context * ctx,
			   int mode,
			   int length,
			   unsigned char iv[16],
			   unsigned char *input, unsigned char *output);

	/**
	 * \brief          AES-CFB128 buffer encryption/decryption
	 *
	 * \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
	 */
	void tiny_aes_crypt_cfb128(tiny_aes_context * ctx,
			      int mode,
			      int length,
			      int *iv_off,
			      unsigned char iv[16],
			      unsigned char *input, unsigned char *output);

#ifdef __cplusplus
}
#endif
#endif				/* aes.h */