1 /* threefish256_enc.c */
3 This file is part of the AVR-Crypto-Lib.
4 Copyright (C) 2009 Daniel Otte (daniel.otte@rub.de)
6 This program is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
21 * \email daniel.otte@rub.de
23 * \license GPLv3 or later
31 #include "threefish.h"
33 #define X(a) (((uint64_t*)data)[(a)])
35 void permute_4(void *data){
43 void add_key_4(void *data, const threefish256_ctx_t *ctx, uint8_t s){
44 X(0) -= ctx->k[(s+0)%5];
45 X(1) -= ctx->k[(s+1)%5] + ctx->t[s%3];
46 X(2) -= ctx->k[(s+2)%5] + ctx->t[(s+1)%3];
47 X(3) -= ctx->k[(s+3)%5] + s;
50 void threefish256_dec(void *data, const threefish256_ctx_t *ctx){
52 uint8_t r0[8] = {0x73, 0x13, 0x7b, 0x32, 0x72, 0x2b, 0x44, 0x1b};
53 uint8_t r1[8] = {0x62, 0x52, 0x43, 0x24, 0x54, 0x6a, 0x34, 0x70};
56 add_key_4(data, ctx, s);
60 threefish_invmix(data, r0[i%8]);
61 threefish_invmix((uint8_t*)data + 16, r1[i%8]);
64 add_key_4(data, ctx, s);