/* aes_enc.c */
/*
- This file is part of the AVR-Crypto-Lib.
- Copyright (C) 2008 Daniel Otte (daniel.otte@rub.de)
+ This file is part of the AVR-Crypto-Lib.
+ Copyright (C) 2008 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 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.
+ 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/>.
-*/
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
/**
* \file aes_enc.c
* \email daniel.otte@rub.de
#include "aes_enc.h"
#include <avr/pgmspace.h>
-void aes_shiftcol(void *data, uint8_t shift){
- uint8_t tmp[4];
- tmp[0] = ((uint8_t*)data)[ 0];
- tmp[1] = ((uint8_t*)data)[ 4];
- tmp[2] = ((uint8_t*)data)[ 8];
- tmp[3] = ((uint8_t*)data)[12];
- ((uint8_t*)data)[ 0] = tmp[(shift+0)&3];
- ((uint8_t*)data)[ 4] = tmp[(shift+1)&3];
- ((uint8_t*)data)[ 8] = tmp[(shift+2)&3];
- ((uint8_t*)data)[12] = tmp[(shift+3)&3];
+void aes_shiftcol(void *data, uint8_t shift)
+{
+ uint8_t tmp[4];
+ tmp[0] = ((uint8_t*) data)[0];
+ tmp[1] = ((uint8_t*) data)[4];
+ tmp[2] = ((uint8_t*) data)[8];
+ tmp[3] = ((uint8_t*) data)[12];
+ ((uint8_t*) data)[0] = tmp[(shift + 0) & 3];
+ ((uint8_t*) data)[4] = tmp[(shift + 1) & 3];
+ ((uint8_t*) data)[8] = tmp[(shift + 2) & 3];
+ ((uint8_t*) data)[12] = tmp[(shift + 3) & 3];
}
#define GF256MUL_1(a) (a)
#define GF256MUL_3(a) (gf256mul(3, (a), 0x1b))
static
-void aes_enc_round(aes_cipher_state_t *state, const aes_roundkey_t *k){
- uint8_t tmp[16], t;
- uint8_t i;
- /* subBytes */
- for(i=0; i<16; ++i){
- tmp[i] = pgm_read_byte(aes_sbox+state->s[i]);
- }
- /* shiftRows */
- aes_shiftcol(tmp+1, 1);
- aes_shiftcol(tmp+2, 2);
- aes_shiftcol(tmp+3, 3);
- /* mixColums */
- for(i=0; i<4; ++i){
- t = tmp[4*i+0] ^ tmp[4*i+1] ^ tmp[4*i+2] ^ tmp[4*i+3];
- state->s[4*i+0] =
- GF256MUL_2(tmp[4*i+0]^tmp[4*i+1])
- ^ tmp[4*i+0]
- ^ t;
- state->s[4*i+1] =
- GF256MUL_2(tmp[4*i+1]^tmp[4*i+2])
- ^ tmp[4*i+1]
- ^ t;
- state->s[4*i+2] =
- GF256MUL_2(tmp[4*i+2]^tmp[4*i+3])
- ^ tmp[4*i+2]
- ^ t;
- state->s[4*i+3] =
- GF256MUL_2(tmp[4*i+3]^tmp[4*i+0])
- ^ tmp[4*i+3]
- ^ t;
- }
+void aes_enc_round(aes_cipher_state_t *state, const aes_roundkey_t *k)
+{
+ uint8_t tmp[16], t;
+ uint8_t i;
+ /* subBytes */
+ for (i = 0; i < 16; ++i) {
+ tmp[i] = pgm_read_byte(aes_sbox + state->s[i]);
+ }
+ /* shiftRows */
+ aes_shiftcol(tmp + 1, 1);
+ aes_shiftcol(tmp + 2, 2);
+ aes_shiftcol(tmp + 3, 3);
+ /* mixColums */
+ for (i = 0; i < 4; ++i) {
+ t = tmp[4 * i + 0] ^ tmp[4 * i + 1] ^ tmp[4 * i + 2] ^ tmp[4 * i + 3];
+ state->s[4 * i + 0] =
+ GF256MUL_2(tmp[4*i+0]^tmp[4*i+1])
+ ^ tmp[4 * i + 0]
+ ^ t;
+ state->s[4 * i + 1] =
+ GF256MUL_2(tmp[4*i+1]^tmp[4*i+2])
+ ^ tmp[4 * i + 1]
+ ^ t;
+ state->s[4 * i + 2] =
+ GF256MUL_2(tmp[4*i+2]^tmp[4*i+3])
+ ^ tmp[4 * i + 2]
+ ^ t;
+ state->s[4 * i + 3] =
+ GF256MUL_2(tmp[4*i+3]^tmp[4*i+0])
+ ^ tmp[4 * i + 3]
+ ^ t;
+ }
- /* addKey */
- for(i=0; i<16; ++i){
- state->s[i] ^= k->ks[i];
- }
+ /* addKey */
+ for (i = 0; i < 16; ++i) {
+ state->s[i] ^= k->ks[i];
+ }
}
-
static
-void aes_enc_lastround(aes_cipher_state_t *state,const aes_roundkey_t *k){
- uint8_t i;
- /* subBytes */
- for(i=0; i<16; ++i){
- state->s[i] = pgm_read_byte(aes_sbox+state->s[i]);
- }
- /* shiftRows */
- aes_shiftcol(state->s+1, 1);
- aes_shiftcol(state->s+2, 2);
- aes_shiftcol(state->s+3, 3);
- /* keyAdd */
- for(i=0; i<16; ++i){
- state->s[i] ^= k->ks[i];
- }
+void aes_enc_lastround(aes_cipher_state_t *state, const aes_roundkey_t *k)
+{
+ uint8_t i;
+ /* subBytes */
+ for (i = 0; i < 16; ++i) {
+ state->s[i] = pgm_read_byte(aes_sbox + state->s[i]);
+ }
+ /* shiftRows */
+ aes_shiftcol(state->s + 1, 1);
+ aes_shiftcol(state->s + 2, 2);
+ aes_shiftcol(state->s + 3, 3);
+ /* keyAdd */
+ for (i = 0; i < 16; ++i) {
+ state->s[i] ^= k->ks[i];
+ }
}
-void aes_encrypt_core(aes_cipher_state_t *state, const aes_genctx_t *ks, uint8_t rounds){
- uint8_t i;
- for(i=0; i<16; ++i){
- state->s[i] ^= ks->key[0].ks[i];
- }
- i=1;
- for(;rounds>1;--rounds){
- aes_enc_round(state, &(ks->key[i]));
- ++i;
- }
- aes_enc_lastround(state, &(ks->key[i]));
+void aes_encrypt_core(aes_cipher_state_t *state, const aes_genctx_t *ks,
+ uint8_t rounds)
+{
+ uint8_t i;
+ for (i = 0; i < 16; ++i) {
+ state->s[i] ^= ks->key[0].ks[i];
+ }
+ i = 1;
+ for (; rounds > 1; --rounds) {
+ aes_enc_round(state, &(ks->key[i]));
+ ++i;
+ }
+ aes_enc_lastround(state, &(ks->key[i]));
}
projects / avr-crypto-lib.git / blobdiff