126 lines
3.0 KiB
C
126 lines
3.0 KiB
C
|
/* twister.c */
|
||
|
/*
|
||
|
This file is part of the Crypto-avr-lib/microcrypt-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 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/>.
|
||
|
*/
|
||
|
|
||
|
#include <stdint.h>
|
||
|
#include <string.h>
|
||
|
#include <avr/pgmspace.h>
|
||
|
#include "twister.h"
|
||
|
#include "twister_tables.h"
|
||
|
#include "memxor.h"
|
||
|
|
||
|
#include "gf256mul.h"
|
||
|
|
||
|
//#define DEBUG
|
||
|
|
||
|
#ifdef DEBUG
|
||
|
# include "uart.h"
|
||
|
#endif
|
||
|
|
||
|
#ifdef DEBUG
|
||
|
# define DEBUG_PRINT(ctx, msg) debug_print((ctx), PSTR(msg))
|
||
|
#else
|
||
|
# define DEBUG_PRINT(ctx, msg)
|
||
|
#endif
|
||
|
|
||
|
#ifdef DEBUG
|
||
|
|
||
|
void print_twister_state(twister_state_t* ctx){
|
||
|
uint8_t i,j;
|
||
|
uart_putstr_P(PSTR("\r\nState:\r\n matrix:\r\n"));
|
||
|
for(i=0; i<8; ++i){
|
||
|
uart_putstr_P(PSTR("\t[ "));
|
||
|
uart_hexdump(&(ctx->s[i][0]), 8);
|
||
|
uart_putstr_P(PSTR("]\r\n"));
|
||
|
}
|
||
|
uart_putstr_P(PSTR("counter: "));
|
||
|
uart_hexdump(&(ctx->counter), 8);
|
||
|
|
||
|
uart_putstr_P(PSTR("\r\nlength_counter_b: "));
|
||
|
uart_hexdump(&(ctx->length_counter_b), 8);
|
||
|
uart_putstr_P(PSTR("\r\n"));
|
||
|
}
|
||
|
|
||
|
void debug_print(twister_state_t* ctx, PGM_P msg){
|
||
|
uart_putstr_P(PSTR("\r\n"));
|
||
|
uart_putstr_P(msg);
|
||
|
print_twister_state(ctx);
|
||
|
}
|
||
|
|
||
|
#endif
|
||
|
|
||
|
static
|
||
|
void shiftrow(void* row, uint8_t shift){
|
||
|
*((uint64_t*)row) = *((uint64_t*)row)>>(8*shift) | *((uint64_t*)row)<<(64-8*shift);
|
||
|
}
|
||
|
|
||
|
#define MDS(a,b) pgm_read_byte(&(twister_mds[a][b]))
|
||
|
//#define MULT(a,b) pgm_read_byte(&(twister_multab[a-1][b]))
|
||
|
#define MULT(a,b) gf256mul(a,b, 0x4D)
|
||
|
|
||
|
void blank_round(twister_state_t* ctx){
|
||
|
uint8_t i,j;
|
||
|
uint8_t tmp[8][8];
|
||
|
DEBUG_PRINT(ctx, "blank init");
|
||
|
/* add twist counter */
|
||
|
for(i=0; i<8; ++i)
|
||
|
ctx->s[i][1] ^= ((uint8_t*)&(ctx->counter))[7-i];
|
||
|
ctx->counter--;
|
||
|
// DEBUG_PRINT(ctx, "counter added");
|
||
|
/* sub bytes */
|
||
|
for(i=0; i<8; ++i)
|
||
|
for(j=0;j<8;++j)
|
||
|
tmp[i][j] = pgm_read_byte(twister_sbox+ctx->s[i][j]);
|
||
|
/* shift rows */
|
||
|
for(i=1;i<8; ++i){
|
||
|
shiftrow(&(tmp[i][0]), i);
|
||
|
}
|
||
|
/* mix columns */
|
||
|
for( i=0; i<8; i++ ){
|
||
|
// multiply with mds matrix
|
||
|
for( j=0; j<8; j++ ){
|
||
|
ctx->s[j][i] =
|
||
|
MULT( MDS(j,0), tmp[0][i] ) ^
|
||
|
MULT( MDS(j,1), tmp[1][i] ) ^
|
||
|
MULT( MDS(j,2), tmp[2][i] ) ^
|
||
|
MULT( MDS(j,3), tmp[3][i] ) ^
|
||
|
MULT( MDS(j,4), tmp[4][i] ) ^
|
||
|
MULT( MDS(j,5), tmp[5][i] ) ^
|
||
|
MULT( MDS(j,6), tmp[6][i] ) ^
|
||
|
MULT( MDS(j,7), tmp[7][i] ) ;
|
||
|
|
||
|
}
|
||
|
}
|
||
|
DEBUG_PRINT(ctx, "post MDS");
|
||
|
}
|
||
|
|
||
|
void mini_round(twister_state_t* ctx, void* msg){
|
||
|
/* inject message */
|
||
|
uint8_t i;
|
||
|
for(i=0; i<8; ++i){
|
||
|
ctx->s[7][7-i] ^= *((uint8_t*)msg);
|
||
|
msg = (uint8_t*)msg +1;
|
||
|
}
|
||
|
blank_round(ctx);
|
||
|
}
|
||
|
|
||
|
|
||
|
|
||
|
|
||
|
|