internal-gift64.h

Go to the documentation of this file.

/*
 * Copyright (C) 2020 Southern Storm Software, Pty Ltd.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

#ifndef LW_INTERNAL_GIFT64_H
#define LW_INTERNAL_GIFT64_H

#include <stddef.h>
#include <stdint.h>

#ifdef __cplusplus
extern "C" {
#endif

#if !defined(GIFT64_LOW_MEMORY)
#if defined(__AVR__)
#define GIFT64_LOW_MEMORY 1
#else
#define GIFT64_LOW_MEMORY 0
#endif
#endif

#define GIFT64_BLOCK_SIZE 8

typedef struct
{
    uint32_t k[4];      
#if !GIFT64_LOW_MEMORY
    uint32_t rk[8];     
#endif

} gift64n_key_schedule_t;

#if GIFT64_LOW_MEMORY
#define gift64n_update_round_keys(ks) do { ; } while (0) /* Not needed */
#else
void gift64n_update_round_keys(gift64n_key_schedule_t *ks);
#endif

void gift64n_init(gift64n_key_schedule_t *ks, const unsigned char *key);

void gift64n_encrypt
    (const gift64n_key_schedule_t *ks, unsigned char *output,
     const unsigned char *input);

void gift64n_decrypt
    (const gift64n_key_schedule_t *ks, unsigned char *output,
     const unsigned char *input);

/* 4-bit tweak values expanded to 16-bit for TweGIFT-64 */
#define GIFT64T_TWEAK_0     0x0000      
#define GIFT64T_TWEAK_1     0xe1e1      
#define GIFT64T_TWEAK_2     0xd2d2      
#define GIFT64T_TWEAK_3     0x3333      
#define GIFT64T_TWEAK_4     0xb4b4      
#define GIFT64T_TWEAK_5     0x5555      
#define GIFT64T_TWEAK_6     0x6666      
#define GIFT64T_TWEAK_7     0x8787      
#define GIFT64T_TWEAK_8     0x7878      
#define GIFT64T_TWEAK_9     0x9999      
#define GIFT64T_TWEAK_10    0xaaaa      
#define GIFT64T_TWEAK_11    0x4b4b      
#define GIFT64T_TWEAK_12    0xcccc      
#define GIFT64T_TWEAK_13    0x2d2d      
#define GIFT64T_TWEAK_14    0x1e1e      
#define GIFT64T_TWEAK_15    0xffff      
void gift64t_encrypt
    (const gift64n_key_schedule_t *ks, unsigned char *output,
     const unsigned char *input, uint16_t tweak);

void gift64t_decrypt
    (const gift64n_key_schedule_t *ks, unsigned char *output,
     const unsigned char *input, uint16_t tweak);

#ifdef __cplusplus
}
#endif

#endif