3 This file is part of the AVR-Crypto-Lib.
4 Copyright (C) 2008 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 * a implementation of the PRESENT block-cipher
23 * email: daniel.otte@rub.de
32 uint8_t present_sbox(uint8_t b){
33 static const uint8_t sb[] = {
39 return ((sb[b >> 4]) << 4) | (sb[b & 0xf]);
42 uint8_t present_sbox_inv(uint8_t b){
43 static const uint8_t sb[] = {
49 return ((sb[b >> 4]) << 4) | (sb[b & 0xf]);
52 void present_p(uint8_t* o, uint8_t* i){
69 void present_generic_enc(void* buffer, uint8_t* ctx, uint8_t ksize_B,
70 void(*update)(uint8_t*, uint8_t)){
71 uint8_t i,j,tmp[8], k[ksize_B];
72 memcpy(k, ctx, ksize_B);
77 tmp[j] = present_sbox(((uint8_t*)buffer)[j]);
79 present_p(buffer, tmp);
85 void present_generic_dec(void* buffer, uint8_t* ctx, uint8_t ksize_B,
86 void(*update)(uint8_t*, uint8_t)){
87 uint8_t j,tmp[8], k[ksize_B];
89 memcpy(k, ctx + ksize_B, ksize_B);
93 present_p(tmp, buffer);
94 present_p(buffer, tmp);
97 ((uint8_t*)buffer)[j] = present_sbox_inv(((uint8_t*)buffer)[j]);
100 memxor(buffer, k, 8);