/* twister.c */
/*
- This file is part of the Crypto-avr-lib/microcrypt-lib.
+ 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
#include "twister_tables.h"
#include "memxor.h"
-#ifndef TWISTER_MUL_TABLE
+//#ifndef TWISTER_MUL_TABLE
# include "gf256mul.h"
-#endif
+//#endif
-#undef DEBUG
+#define MDS(a,b) pgm_read_byte(&(twister_mds[(a)][(b)]))
-#ifdef DEBUG
-# include "uart.h"
-#endif
+//#ifdef TWISTER_MUL_TABLE
+//# define MULT(a,b) pgm_read_byte(&(twister_multab[(a)][(b)]))
+//#else
+# define MULT(a,b) gf256mul((a),(b), 0x4D)
+//#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;
- 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]))
-
-#ifdef TWISTER_MUL_TABLE
-# define MULT(a,b) pgm_read_byte(&(twister_multab[a][b]))
-#else
-# define MULT(a,b) gf256mul(a,b, 0x4D)
-#endif
void twister_blank_round(twister_state_t* ctx){
- uint8_t i,j;
+ uint8_t i,j,k;
uint8_t tmp[8][8];
- DEBUG_PRINT(ctx, "blank init");
/* add twist counter */
- for(i=0; i<8; ++i)
+ 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)
+ 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 */
+ /* mix columns with integrates shift rows */
for( i=0; i<8; i++ ){
// multiply with mds matrix
for( j=0; j<8; j++ ){
+ k=(i+1)&7;
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] ) ;
+ MULT( MDS(j,0), (tmp[0][i]) );
+ ctx->s[j][i] ^=
+ MULT( MDS(j,1), (tmp[1][k]) );
+ ctx->s[j][i] ^=
+ MULT( MDS(j,2), (tmp[2][((++k)&7)]) );
+ ctx->s[j][i] ^=
+ MULT( MDS(j,3), (tmp[3][((++k)&7)]) );
+ ctx->s[j][i] ^=
+ MULT( MDS(j,4), (tmp[4][((++k)&7)]) );
+ ctx->s[j][i] ^=
+ MULT( MDS(j,5), (tmp[5][((++k)&7)]) );
+ ctx->s[j][i] ^=
+ MULT( MDS(j,6), (tmp[6][((++k)&7)]) );
+ ctx->s[j][i] ^=
+ MULT( MDS(j,7), (tmp[7][((++k)&7)]) );
}
}
- DEBUG_PRINT(ctx, "post MDS");
}
-
-void twister_mini_round(twister_state_t* ctx, void* msg){
+void twister_mini_round(twister_state_t* ctx, const void* msg){
/* inject message */
uint8_t i;
for(i=0; i<8; ++i){