/* aes_keyschedule.c */
/*
- This file is part of the AVR-Crypto-Lib.
- Copyright (C) 2008, 2009 Daniel Otte (daniel.otte@rub.de)
+ This file is part of the AVR-Crypto-Lib.
+ Copyright (C) 2008, 2009 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_keyschedule.c
* \email daniel.otte@rub.de
#include <avr/pgmspace.h>
static
-void aes_rotword(void *a){
- uint8_t t;
- t=((uint8_t*)a)[0];
- ((uint8_t*)a)[0] = ((uint8_t*)a)[1];
- ((uint8_t*)a)[1] = ((uint8_t*)a)[2];
- ((uint8_t*)a)[2] = ((uint8_t*)a)[3];
- ((uint8_t*)a)[3] = t;
+void aes_rotword(void *a)
+{
+ uint8_t t;
+ t = ((uint8_t*) a)[0];
+ ((uint8_t*) a)[0] = ((uint8_t*) a)[1];
+ ((uint8_t*) a)[1] = ((uint8_t*) a)[2];
+ ((uint8_t*) a)[2] = ((uint8_t*) a)[3];
+ ((uint8_t*) a)[3] = t;
}
const uint8_t rc_tab[] PROGMEM = { 0x01, 0x02, 0x04, 0x08,
- 0x10, 0x20, 0x40, 0x80,
- 0x1b, 0x36 };
+ 0x10, 0x20, 0x40, 0x80,
+ 0x1b, 0x36 };
-void aes_init(const void *key, uint16_t keysize_b, aes_genctx_t *ctx){
- uint8_t hi,i,nk, next_nk;
- uint8_t rc=0;
- union {
- uint32_t v32;
- uint8_t v8[4];
- } tmp;
- nk=keysize_b>>5; /* 4, 6, 8 */
- hi=4*(nk+6+1);
- memcpy(ctx, key, keysize_b/8);
- next_nk = nk;
- for(i=nk;i<hi;++i){
- tmp.v32 = ((uint32_t*)(ctx->key[0].ks))[i-1];
- if(i!=next_nk){
- if(nk==8 && i%8==4){
- tmp.v8[0] = pgm_read_byte(aes_sbox+tmp.v8[0]);
- tmp.v8[1] = pgm_read_byte(aes_sbox+tmp.v8[1]);
- tmp.v8[2] = pgm_read_byte(aes_sbox+tmp.v8[2]);
- tmp.v8[3] = pgm_read_byte(aes_sbox+tmp.v8[3]);
- }
- } else {
- next_nk += nk;
- aes_rotword(&(tmp.v32));
- tmp.v8[0] = pgm_read_byte(aes_sbox+tmp.v8[0]);
- tmp.v8[1] = pgm_read_byte(aes_sbox+tmp.v8[1]);
- tmp.v8[2] = pgm_read_byte(aes_sbox+tmp.v8[2]);
- tmp.v8[3] = pgm_read_byte(aes_sbox+tmp.v8[3]);
- tmp.v8[0] ^= pgm_read_byte(rc_tab+rc);
- rc++;
- }
- ((uint32_t*)(ctx->key[0].ks))[i] = ((uint32_t*)(ctx->key[0].ks))[i-nk]
- ^ tmp.v32;
- }
+void aes_init(const void *key, uint16_t keysize_b, aes_genctx_t *ctx)
+{
+ uint8_t hi, i, nk, next_nk;
+ uint8_t rc = 0;
+ union {
+ uint32_t v32;
+ uint8_t v8[4];
+ } tmp;
+ nk = keysize_b >> 5; /* 4, 6, 8 */
+ hi = 4 * (nk + 6 + 1);
+ memcpy(ctx, key, keysize_b / 8);
+ next_nk = nk;
+ for (i = nk; i < hi; ++i) {
+ tmp.v32 = ((uint32_t*) (ctx->key[0].ks))[i - 1];
+ if (i != next_nk) {
+ if (nk == 8 && i % 8 == 4) {
+ tmp.v8[0] = pgm_read_byte(aes_sbox + tmp.v8[0]);
+ tmp.v8[1] = pgm_read_byte(aes_sbox + tmp.v8[1]);
+ tmp.v8[2] = pgm_read_byte(aes_sbox + tmp.v8[2]);
+ tmp.v8[3] = pgm_read_byte(aes_sbox + tmp.v8[3]);
+ }
+ } else {
+ next_nk += nk;
+ aes_rotword(&(tmp.v32));
+ tmp.v8[0] = pgm_read_byte(aes_sbox + tmp.v8[0]);
+ tmp.v8[1] = pgm_read_byte(aes_sbox + tmp.v8[1]);
+ tmp.v8[2] = pgm_read_byte(aes_sbox + tmp.v8[2]);
+ tmp.v8[3] = pgm_read_byte(aes_sbox + tmp.v8[3]);
+ tmp.v8[0] ^= pgm_read_byte(rc_tab + rc);
+ rc++;
+ }
+ ((uint32_t*) (ctx->key[0].ks))[i] = ((uint32_t*) (ctx->key[0].ks))[i
+ - nk]
+ ^ tmp.v32;
+ }
}
-void aes128_init(const void *key, aes128_ctx_t *ctx){
- aes_init(key, 128, (aes_genctx_t*)ctx);
+void aes128_init(const void *key, aes128_ctx_t *ctx)
+{
+ aes_init(key, 128, (aes_genctx_t*) ctx);
}
-void aes192_init(const void *key, aes192_ctx_t *ctx){
- aes_init(key, 192, (aes_genctx_t*)ctx);
+void aes192_init(const void *key, aes192_ctx_t *ctx)
+{
+ aes_init(key, 192, (aes_genctx_t*) ctx);
}
-void aes256_init(const void *key, aes256_ctx_t *ctx){
- aes_init(key, 256, (aes_genctx_t*)ctx);
+void aes256_init(const void *key, aes256_ctx_t *ctx)
+{
+ aes_init(key, 256, (aes_genctx_t*) ctx);
}
projects / avr-crypto-lib.git / blobdiff