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))
51 void aes_enc_round(aes_cipher_state_t* state, const aes_roundkey_t* k){
56 tmp[i] = pgm_read_byte(aes_sbox+state->s[i]);
59 aes_shiftrow(tmp+4, 1);
60 aes_shiftrow(tmp+8, 2);
61 aes_shiftrow(tmp+12, 3);
65 GF256MUL_2(tmp[4*0+i])
66 ^ GF256MUL_3(tmp[4*1+i])
67 ^ GF256MUL_1(tmp[4*2+i])
68 ^ GF256MUL_1(tmp[4*3+i]);
70 GF256MUL_1(tmp[4*0+i])
71 ^ GF256MUL_2(tmp[4*1+i])
72 ^ GF256MUL_3(tmp[4*2+i])
73 ^ GF256MUL_1(tmp[4*3+i]);
75 GF256MUL_1(tmp[4*0+i])
76 ^ GF256MUL_1(tmp[4*1+i])
77 ^ GF256MUL_2(tmp[4*2+i])
78 ^ GF256MUL_3(tmp[4*3+i]);
80 GF256MUL_3(tmp[4*0+i])
81 ^ GF256MUL_1(tmp[4*1+i])
82 ^ GF256MUL_1(tmp[4*2+i])
83 ^ GF256MUL_2(tmp[4*3+i]);
88 state->s[i] ^= k->ks[i];
94 void aes_enc_lastround(aes_cipher_state_t* state,const aes_roundkey_t* k){
98 state->s[i] = pgm_read_byte(aes_sbox+state->s[i]);
101 aes_shiftrow(state->s+4, 1);
102 aes_shiftrow(state->s+8, 2);
103 aes_shiftrow(state->s+12, 3);
106 state->s[i] ^= k->ks[i];
110 void aes_encrypt_core(aes_cipher_state_t* state, const aes_genctx_t* ks, uint8_t rounds){
113 state->s[i] ^= ks->key[0].ks[i];
116 for(;rounds>1;--rounds){
117 aes_enc_round(state, &(ks->key[i]));
120 aes_enc_lastround(state, &(ks->key[i]));