3 This file is part of the Crypto-avr-lib/microcrypt-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 * \email daniel.otte@rub.de
24 * \license GPLv3 or later
34 #include <avr/pgmspace.h>
37 void aes_shiftrow(void* data, uint8_t shift){
39 tmp[0] = ((uint8_t*)data)[(0+shift)&3];
40 tmp[1] = ((uint8_t*)data)[(1+shift)&3];
41 tmp[2] = ((uint8_t*)data)[(2+shift)&3];
42 tmp[3] = ((uint8_t*)data)[(3+shift)&3];
46 #define GF256MUL_1(a) (a)
47 #define GF256MUL_2(a) (gf256mul(2, (a), 0x1b))
48 #define GF256MUL_3(a) (gf256mul(3, (a), 0x1b))
53 void aes_enc_round(aes_cipher_state_t* state, const aes_roundkey_t* k){
58 tmp[i] = pgm_read_byte(aes_sbox+state->s[i]);
61 aes_shiftrow(tmp+4, 1);
62 aes_shiftrow(tmp+8, 2);
63 aes_shiftrow(tmp+12, 3);
67 GF256MUL_2(tmp[4*0+i])
68 ^ GF256MUL_3(tmp[4*1+i])
69 ^ GF256MUL_1(tmp[4*2+i])
70 ^ GF256MUL_1(tmp[4*3+i]);
72 GF256MUL_1(tmp[4*0+i])
73 ^ GF256MUL_2(tmp[4*1+i])
74 ^ GF256MUL_3(tmp[4*2+i])
75 ^ GF256MUL_1(tmp[4*3+i]);
77 GF256MUL_1(tmp[4*0+i])
78 ^ GF256MUL_1(tmp[4*1+i])
79 ^ GF256MUL_2(tmp[4*2+i])
80 ^ GF256MUL_3(tmp[4*3+i]);
82 GF256MUL_3(tmp[4*0+i])
83 ^ GF256MUL_1(tmp[4*1+i])
84 ^ GF256MUL_1(tmp[4*2+i])
85 ^ GF256MUL_2(tmp[4*3+i]);
90 state->s[i] ^= k->ks[i];
96 void aes_enc_lastround(aes_cipher_state_t* state,const aes_roundkey_t* k){
100 state->s[i] = pgm_read_byte(aes_sbox+state->s[i]);
103 aes_shiftrow(state->s+4, 1);
104 aes_shiftrow(state->s+8, 2);
105 aes_shiftrow(state->s+12, 3);
108 state->s[i] ^= k->ks[i];
112 void aes_encrypt_core(aes_cipher_state_t* state, const aes_genctx_t* ks, uint8_t rounds){
115 state->s[i] ^= ks->key[0].ks[i];
118 for(;rounds>1;--rounds){
119 aes_enc_round(state, &(ks->key[i]));
122 aes_enc_lastround(state, &(ks->key[i]));