75 lines
1.9 KiB
C
75 lines
1.9 KiB
C
/* threefish256_enc.c */
|
|
/*
|
|
This file is part of the ARM-Crypto-Lib.
|
|
Copyright (C) 2006-2010 Daniel Otte (daniel.otte@rub.de)
|
|
|
|
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 3 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/>.
|
|
*/
|
|
/*
|
|
* \author Daniel Otte
|
|
* \email daniel.otte@rub.de
|
|
* \date 2009-03-12
|
|
* \license GPLv3 or later
|
|
*
|
|
*
|
|
*
|
|
*/
|
|
|
|
#include <stdint.h>
|
|
#include <string.h>
|
|
#include "threefish.h"
|
|
|
|
#define X(a) (((uint64_t*)data)[(a)])
|
|
static
|
|
void permute_4(void* data){
|
|
uint64_t t;
|
|
t = X(1);
|
|
X(1) = X(3);
|
|
X(3) = t;
|
|
}
|
|
|
|
#define K(s) (((uint64_t*)key)[(s)])
|
|
#define T(s) (((uint64_t*)tweak)[(s)])
|
|
|
|
static
|
|
void add_key_4(void* data, const threefish256_ctx_t* ctx, uint8_t s){
|
|
X(0) -= ctx->k[(s+0)%5];
|
|
X(1) -= ctx->k[(s+1)%5] + ctx->t[s%3];
|
|
X(2) -= ctx->k[(s+2)%5] + ctx->t[(s+1)%3];
|
|
X(3) -= ctx->k[(s+3)%5] + s;
|
|
}
|
|
|
|
void threefish256_dec(void* data, const threefish256_ctx_t* ctx){
|
|
uint8_t i=0,s=18;
|
|
/* old constans, changed at round 2 of the SHA-3 contest
|
|
uint8_t r0[8] = {59, 11, 53, 26, 58, 13, 36, 5};
|
|
uint8_t r1[8] = {50, 42, 35, 20, 44, 46, 28, 56};
|
|
*/
|
|
uint8_t r0[8] = { 32, 58, 46, 25, 5, 23, 52, 14};
|
|
uint8_t r1[8] = { 32, 22, 12, 33, 37, 40, 57, 16};
|
|
|
|
do{
|
|
if(i%4==0){
|
|
add_key_4(data, ctx, s);
|
|
--s;
|
|
}
|
|
permute_4(data);
|
|
threefish_invmix(data, r0[i%8]);
|
|
threefish_invmix((uint8_t*)data + 16, r1[i%8]);
|
|
++i;
|
|
}while(i!=72);
|
|
add_key_4(data, ctx, s);
|
|
}
|
|
|