/*
* FIPS-197 compliant AES implementation
*
* Copyright (C) 2001-2004 Christophe Devine
*
* 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 2 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "aes.h"
/* uncomment the following line to run the test suite */
/* #define TEST */
/* uncomment the following line to use pre-computed tables */
/* otherwise the tables will be generated at the first run */
/* #define FIXED_TABLES */
#ifndef FIXED_TABLES
/* forward S-box & tables */
uint32 FSb[256];
uint32 FT0[256];
uint32 FT1[256];
uint32 FT2[256];
uint32 FT3[256];
/* reverse S-box & tables */
uint32 RSb[256];
uint32 RT0[256];
uint32 RT1[256];
uint32 RT2[256];
uint32 RT3[256];
/* round constants */
uint32 RCON[10];
/* tables generation flag */
int do_init = 1;
/* tables generation routine */
#define ROTR8(x) ( ( ( x << 24 ) & 0xFFFFFFFF ) | \
( ( x & 0xFFFFFFFF ) >> 8 ) )
#define XTIME(x) ( ( x << 1 ) ^ ( ( x & 0x80 ) ? 0x1B : 0x00 ) )
#define MUL(x,y) ( ( x && y ) ? pow[(log[x] + log[y]) % 255] : 0 )
void aes_gen_tables( void )
{
int i;
uint8 x, y;
uint8 pow[256];
uint8 log[256];
/* compute pow and log tables over GF(2^8) */
for( i = 0, x = 1; i < 256; i++, x ^= XTIME( x ) )
{
pow[i] = x;
log[x] = i;
}
/* calculate the round constants */
for( i = 0, x = 1; i < 10; i++, x = XTIME( x ) )
{
RCON[i] = (uint32) x << 24;
}
/* generate the forward and reverse S-boxes */
FSb[0x00] = 0x63;
RSb[0x63] = 0x00;
for( i = 1; i < 256; i++ )
{
x = pow[255 - log[i]];
y = x; y = ( y << 1 ) | ( y >> 7 );
x ^= y; y = ( y << 1 ) | ( y >> 7 );
x ^= y; y = ( y << 1 ) | ( y >> 7 );
x ^= y; y = ( y << 1 ) | ( y >> 7 );
x ^= y ^ 0x63;
FSb[i] = x;
RSb[x] = i;
}
/* generate the forward and reverse tables */
for( i = 0; i < 256; i++ )
{
x = (unsigned char) FSb[i]; y = XTIME( x );
FT0[i] = (uint32) ( x ^ y ) ^
( (uint32) x << 8 ) ^
( (uint32) x << 16 ) ^
( (uint32) y << 24 );
FT0[i] &= 0xFFFFFFFF;
FT1[i] = ROTR8( FT0[i] );
FT2[i] = ROTR8( FT1[i] );
FT3[i] = ROTR8( FT2[i] );
y = (unsigned char) RSb[i];
RT0[i] = ( (uint32) MUL( 0x0B, y ) ) ^
( (uint32) MUL( 0x0D, y ) << 8 ) ^
( (uint32) MUL( 0x09, y ) << 16 ) ^
( (uint32) MUL( 0x0E, y ) << 24 );
RT0[i] &= 0xFFFFFFFF;
RT1[i] = ROTR8( RT0[i] );
RT2[i] = ROTR8( RT1[i] );
RT3[i] = ROTR8( RT2[i] );
}
}
#else
/* forward S-box */
static const uint32 FSb[256] =
{
0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5,
0x30, 0x01, 0x67, 0x2B, 0xFE, 0xD7, 0xAB, 0x76,
0xCA, 0x82, 0xC9, 0x7D, 0xFA, 0x59, 0x47, 0xF0,
0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4, 0x72, 0xC0,
0xB7, 0xFD, 0x93, 0x26, 0x36, 0x3F, 0xF7, 0xCC,
0x34, 0xA5, 0xE5, 0xF1, 0x71, 0xD8, 0x31, 0x15,
0x04, 0xC7, 0x23, 0xC3, 0x18, 0x96, 0x05, 0x9A,
0x07, 0x12, 0x80, 0xE2, 0xEB, 0x27, 0xB2, 0x75,
0x09, 0x83, 0x2C, 0x1A, 0x1B, 0x6E, 0x5A, 0xA0,
0x52, 0x3B, 0xD6, 0xB3, 0x29, 0xE3, 0x2F, 0x84,
0x53, 0xD1, 0x00, 0xED, 0x20, 0xFC, 0xB1, 0x5B,
0x6A, 0xCB, 0xBE, 0x39, 0x4A, 0x4C, 0x58, 0xCF,
0xD0, 0xEF, 0xAA, 0xFB, 0x43, 0x4D, 0x33, 0x85,
0x45, 0xF9, 0x02, 0x7F, 0x50, 0x3C, 0x9F, 0xA8,
0x51, 0xA3, 0x40, 0x8F, 0x92, 0x9D, 0x38, 0xF5,
0xBC, 0xB6, 0xDA, 0x21, 0x10, 0xFF, 0xF3, 0xD2,
0xCD, 0x0C, 0x13, 0xEC, 0x5F, 0x97, 0x44, 0x17,
0xC4, 0xA7, 0x7E, 0x3D, 0x64, 0x5D, 0x19, 0x73,
0x60, 0x81, 0x4F, 0xDC, 0x22, 0x2A, 0x90, 0x88,
0x46, 0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB,
0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C,
0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79,
0xE7, 0xC8, 0x37, 0x6D, 0x8D, 0xD5, 0x4E, 0xA9,
0x6C, 0x56, 0xF4, 0xEA, 0x65, 0x7A, 0xAE, 0x08,
0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6,
0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A,
0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E,
0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E,
0xE1, 0xF8, 0x98, 0x11, 0x69, 0xD9, 0x8E, 0x94,
0x9B, 0x1E, 0x87, 0xE9, 0xCE, 0x55, 0x28, 0xDF,
0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68,
0x41, 0x99, 0x2D, 0x0F, 0xB0, 0x54, 0xBB, 0x16
};
/* forward tables */
#define FT \
\
V(C6,63,63,A5), V(F8,7C,7C,84), V(EE,77,77,99), V(F6,7B,7B,8D), \
V(FF,F2,F2,0D), V(D6,6B,6B,BD), V(DE,6F,6F,B1), V(91,C5,C5,54), \
V(60,30,30,50), V(02,01,01,03), V(CE,67,67,A9), V(56,2B,2B,7D), \
V(E7,FE,FE,19), V(B5,D7,D7,62), V(4D,AB,AB,E6), V(EC,76,76,9A), \
V(8F,CA,CA,45), V(1F,82,82,9D), V(89,C9,C9,40), V(FA,7D,7D,87), \
V(EF,FA,FA,15), V(B2,59,59,EB), V(8E,47,47,C9), V(FB,F0,F0,0B), \
V(41,AD,AD,EC), V(B3,D4,D4,67), V(5F,A2,A2,FD), V(45,AF,AF,EA), \
V(23,9C,9C,BF), V(53,A4,A4,F7), V(E4,72,72,96), V(9B,C0,C0,5B), \
V(75,B7,B7,C2), V(E1,FD,FD,1C), V(3D,93,93,AE), V(4C,26,26,6A), \
V(6C,36,36,5A), V(7E,3F,3F,41), V(F5,F7,F7,02), V(83,CC,CC,4F), \
V(68,34,34,5C), V(51,A5,A5,F4), V(D1,E5,E5,34), V(F9,F1,F1,08), \
V(E2,71,71,93), V(AB,D8,D8,73), V(62,31,31,53), V(2A,15,15,3F), \
V(08,04,04,0C), V(95,C7,C7,52), V(46,23,23,65), V(9D,C3,C3,5E), \
V(30,18,18,28), V(37,96,96,A1), V(0A,05,05,0F), V(2F,9A,9A,B5), \
V(0E,07,07,09), V(24,12,12,36), V(1B,80,80,9B), V(DF,E2,E2,3D), \
V(CD,EB,EB,26), V(4E,27,27,69), V(7F,B2,B2,CD), V(EA,75,75,9F), \
V(12,09,09,1B), V(1D,83,83,9E), V(58,2C,2C,74), V(34,1A,1A,2E), \
V(36,1B,1B,2D), V(DC,6E,6E,B2), V(B4,5A,5A,EE), V(5B,A0,A0,FB), \
V(A4,52,52,F6), V(76,3B,3B,4D), V(B7,D6,D6,61), V(7D,B3,B3,CE), \
V(52,29,29,7B), V(DD,E3,E3,3E), V(5E,2F,2F,71), V(13,84,84,97), \
V(A6,53,53,F5), V(B9,D1,D1,68), V(00,00,00,00), V(C1,ED,ED,2C), \
V(40,20,20,60), V(E3,FC,FC,1F), V(79,B1,B1,C8), V(B6,5B,5B,ED), \
V(D4,6A,6A,BE), V(8D,CB,CB,46), V(67,BE,BE,D9), V(72,39,39,4B), \
V(94,4A,4A,DE), V(98,4C,4C,D4), V(B0,58,58,E8), V(85,CF,CF,4A), \
V(BB,D0,D0,6B), V(C5,EF,EF,2A), V(4F,AA,AA,E5), V(ED,FB,FB,16), \
V(86,43,43,C5), V(9A,4D,4D,D7), V(66,33,33,55), V(11,85,85,94), \
V(8A,45,45,CF), V(E9,F9,F9,10), V(04,02,02,06), V(FE,7F,7F,81), \
V(A0,50,50,F0), V(78,3C,3C,44), V(25,9F,9F,BA), V(4B,A8,A8,E3), \
V(A2,51,51,F3), V(5D,A3,A3,FE), V(80,40,40,C0), V(05,8F,8F,8A), \
V(3F,92,92,AD), V(21,9D,9D,BC), V(70,38,38,48), V(F1,F5,F5,04), \
V(63,BC,BC,DF), V(77,B6,B6,C1), V(AF,DA,DA,75), V(42,21,21,63), \
V(20,10,10,30), V(E5,FF,FF,1A), V(FD,F3,F3,0E), V(BF,D2,D2,6D), \
V(81,CD,CD,4C), V(18,0C,0C,14), V(26,13,13,35), V(C3,EC,EC,2F), \
V(BE,5F,5F,E1), V(35,97,97,A2), V(88,44,44,CC), V(2E,17,17,39), \
V(93,C4,C4,57), V(55,A7,A7,F2), V(FC,7E,7E,82), V(7A,3D,3D,47), \
V(C8,64,64,AC), V(BA,5D,5D,E7), V(32,19,19,2B), V(E6,73,73,95), \
V(C0,60,60,A0), V(19,81,81,98), V(9E,4F,4F,D1), V(A3,DC,DC,7F), \
V(44,22,22,66), V(54,2A,2A,7E), V(3B,90,90,AB), V(0B,88,88,83), \
V(8C,46,46,CA), V(C7,EE,EE,29), V(6B,B8,B8,D3), V(28,14,14,3C), \
V(A7,DE,DE,79), V(BC,5E,5E,E2), V(16,0B,0B,1D), V(AD,DB,DB,76), \
V(DB,E0,E0,3B), V(64,32,32,56), V(74,3A,3A,4E), V(14,0A,0A,1E), \
V(92,49,49,DB), V(0C,06,0
