aes.c

一种基于keygen的加密算法

/*
 * Reverse S-box
 */
static const uint8 RSb[256] =
{
    0x52, 0x09, 0x6A, 0xD5, 0x30, 0x36, 0xA5, 0x38,
    0xBF, 0x40, 0xA3, 0x9E, 0x81, 0xF3, 0xD7, 0xFB,
    0x7C, 0xE3, 0x39, 0x82, 0x9B, 0x2F, 0xFF, 0x87,
    0x34, 0x8E, 0x43, 0x44, 0xC4, 0xDE, 0xE9, 0xCB,
    0x54, 0x7B, 0x94, 0x32, 0xA6, 0xC2, 0x23, 0x3D,
    0xEE, 0x4C, 0x95, 0x0B, 0x42, 0xFA, 0xC3, 0x4E,
    0x08, 0x2E, 0xA1, 0x66, 0x28, 0xD9, 0x24, 0xB2,
    0x76, 0x5B, 0xA2, 0x49, 0x6D, 0x8B, 0xD1, 0x25,
    0x72, 0xF8, 0xF6, 0x64, 0x86, 0x68, 0x98, 0x16,
    0xD4, 0xA4, 0x5C, 0xCC, 0x5D, 0x65, 0xB6, 0x92,
    0x6C, 0x70, 0x48, 0x50, 0xFD, 0xED, 0xB9, 0xDA,
    0x5E, 0x15, 0x46, 0x57, 0xA7, 0x8D, 0x9D, 0x84,
    0x90, 0xD8, 0xAB, 0x00, 0x8C, 0xBC, 0xD3, 0x0A,
    0xF7, 0xE4, 0x58, 0x05, 0xB8, 0xB3, 0x45, 0x06,
    0xD0, 0x2C, 0x1E, 0x8F, 0xCA, 0x3F, 0x0F, 0x02,
    0xC1, 0xAF, 0xBD, 0x03, 0x01, 0x13, 0x8A, 0x6B,
    0x3A, 0x91, 0x11, 0x41, 0x4F, 0x67, 0xDC, 0xEA,
    0x97, 0xF2, 0xCF, 0xCE, 0xF0, 0xB4, 0xE6, 0x73,
    0x96, 0xAC, 0x74, 0x22, 0xE7, 0xAD, 0x35, 0x85,
    0xE2, 0xF9, 0x37, 0xE8, 0x1C, 0x75, 0xDF, 0x6E,
    0x47, 0xF1, 0x1A, 0x71, 0x1D, 0x29, 0xC5, 0x89,
    0x6F, 0xB7, 0x62, 0x0E, 0xAA, 0x18, 0xBE, 0x1B,
    0xFC, 0x56, 0x3E, 0x4B, 0xC6, 0xD2, 0x79, 0x20,
    0x9A, 0xDB, 0xC0, 0xFE, 0x78, 0xCD, 0x5A, 0xF4,
    0x1F, 0xDD, 0xA8, 0x33, 0x88, 0x07, 0xC7, 0x31,
    0xB1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xEC, 0x5F,
    0x60, 0x51, 0x7F, 0xA9, 0x19, 0xB5, 0x4A, 0x0D,
    0x2D, 0xE5, 0x7A, 0x9F, 0x93, 0xC9, 0x9C, 0xEF,
    0xA0, 0xE0, 0x3B, 0x4D, 0xAE, 0x2A, 0xF5, 0xB0,
    0xC8, 0xEB, 0xBB, 0x3C, 0x83, 0x53, 0x99, 0x61,
    0x17, 0x2B, 0x04, 0x7E, 0xBA, 0x77, 0xD6, 0x26,
    0xE1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0C, 0x7D
};

/*
 * Reverse tables
 */
#define RT \
\
    V(51,F4,A7,50), V(7E,41,65,53), V(1A,17,A4,C3), V(3A,27,5E,96), \
    V(3B,AB,6B,CB), V(1F,9D,45,F1), V(AC,FA,58,AB), V(4B,E3,03,93), \
    V(20,30,FA,55), V(AD,76,6D,F6), V(88,CC,76,91), V(F5,02,4C,25), \
    V(4F,E5,D7,FC), V(C5,2A,CB,D7), V(26,35,44,80), V(B5,62,A3,8F), \
    V(DE,B1,5A,49), V(25,BA,1B,67), V(45,EA,0E,98), V(5D,FE,C0,E1), \
    V(C3,2F,75,02), V(81,4C,F0,12), V(8D,46,97,A3), V(6B,D3,F9,C6), \
    V(03,8F,5F,E7), V(15,92,9C,95), V(BF,6D,7A,EB), V(95,52,59,DA), \
    V(D4,BE,83,2D), V(58,74,21,D3), V(49,E0,69,29), V(8E,C9,C8,44), \
    V(75,C2,89,6A), V(F4,8E,79,78), V(99,58,3E,6B), V(27,B9,71,DD), \
    V(BE,E1,4F,B6), V(F0,88,AD,17), V(C9,20,AC,66), V(7D,CE,3A,B4), \
    V(63,DF,4A,18), V(E5,1A,31,82), V(97,51,33,60), V(62,53,7F,45), \
    V(B1,64,77,E0), V(BB,6B,AE,84), V(FE,81,A0,1C), V(F9,08,2B,94), \
    V(70,48,68,58), V(8F,45,FD,19), V(94,DE,6C,87), V(52,7B,F8,B7), \
    V(AB,73,D3,23), V(72,4B,02,E2), V(E3,1F,8F,57), V(66,55,AB,2A), \
    V(B2,EB,28,07), V(2F,B5,C2,03), V(86,C5,7B,9A), V(D3,37,08,A5), \
    V(30,28,87,F2), V(23,BF,A5,B2), V(02,03,6A,BA), V(ED,16,82,5C), \
    V(8A,CF,1C,2B), V(A7,79,B4,92), V(F3,07,F2,F0), V(4E,69,E2,A1), \
    V(65,DA,F4,CD), V(06,05,BE,D5), V(D1,34,62,1F), V(C4,A6,FE,8A), \
    V(34,2E,53,9D), V(A2,F3,55,A0), V(05,8A,E1,32), V(A4,F6,EB,75), \
    V(0B,83,EC,39), V(40,60,EF,AA), V(5E,71,9F,06), V(BD,6E,10,51), \
    V(3E,21,8A,F9), V(96,DD,06,3D), V(DD,3E,05,AE), V(4D,E6,BD,46), \
    V(91,54,8D,B5), V(71,C4,5D,05), V(04,06,D4,6F), V(60,50,15,FF), \
    V(19,98,FB,24), V(D6,BD,E9,97), V(89,40,43,CC), V(67,D9,9E,77), \
    V(B0,E8,42,BD), V(07,89,8B,88), V(E7,19,5B,38), V(79,C8,EE,DB), \
    V(A1,7C,0A,47), V(7C,42,0F,E9), V(F8,84,1E,C9), V(00,00,00,00), \
    V(09,80,86,83), V(32,2B,ED,48), V(1E,11,70,AC), V(6C,5A,72,4E), \
    V(FD,0E,FF,FB), V(0F,85,38,56), V(3D,AE,D5,1E), V(36,2D,39,27), \
    V(0A,0F,D9,64), V(68,5C,A6,21), V(9B,5B,54,D1), V(24,36,2E,3A), \
    V(0C,0A,67,B1), V(93,57,E7,0F), V(B4,EE,96,D2), V(1B,9B,91,9E), \
    V(80,C0,C5,4F), V(61,DC,20,A2), V(5A,77,4B,69), V(1C,12,1A,16), \
    V(E2,93,BA,0A), V(C0,A0,2A,E5), V(3C,22,E0,43), V(12,1B,17,1D), \
    V(0E,09,0D,0B), V(F2,8B,C7,AD), V(2D,B6,A8,B9), V(14,1E,A9,C8), \
    V(57,F1,19,85), V(AF,75,07,4C), V(EE,99,DD,BB), V(A3,7F,60,FD), \
    V(F7,01,26,9F), V(5C,72,F5,BC), V(44,66,3B,C5), V(5B,FB,7E,34), \
    V(8B,43,29,76), V(CB,23,C6,DC), V(B6,ED,FC,68), V(B8,E4,F1,63), \
    V(D7,31,DC,CA), V(42,63,85,10), V(13,97,22,40), V(84,C6,11,20), \
    V(85,4A,24,7D), V(D2,BB,3D,F8), V(AE,F9,32,11), V(C7,29,A1,6D), \
    V(1D,9E,2F,4B), V(DC,B2,30,F3), V(0D,86,52,EC), V(77,C1,E3,D0), \
    V(2B,B3,16,6C), V(A9,70,B9,99), V(11,94,48,FA), V(47,E9,64,22), \
    V(A8,FC,8C,C4), V(A0,F0,3F,1A), V(56,7D,2C,D8), V(22,33,90,EF), \
    V(87,49,4E,C7), V(D9,38,D1,C1), V(8C,CA,A2,FE), V(98,D4,0B,36), \
    V(A6,F5,81,CF), V(A5,7A,DE,28), V(DA,B7,8E,26), V(3F,AD,BF,A4), \
    V(2C,3A,9D,E4), V(50,78,92,0D), V(6A,5F,CC,9B), V(54,7E,46,62), \
    V(F6,8D,13,C2), V(90,D8,B8,E8), V(2E,39,F7,5E), V(82,C3,AF,F5), \
    V(9F,5D,80,BE), V(69,D0,93,7C), V(6F,D5,2D,A9), V(CF,25,12,B3), \
    V(C8,AC,99,3B), V(10,18,7D,A7), V(E8,9C,63,6E), V(DB,3B,BB,7B), \
    V(CD,26,78,09), V(6E,59,18,F4), V(EC,9A,B7,01), V(83,4F,9A,A8), \
    V(E6,95,6E,65), V(AA,FF,E6,7E), V(21,BC,CF,08), V(EF,15,E8,E6), \
    V(BA,E7,9B,D9), V(4A,6F,36,CE), V(EA,9F,09,D4), V(29,B0,7C,D6), \
    V(31,A4,B2,AF), V(2A,3F,23,31), V(C6,A5,94,30), V(35,A2,66,C0), \
    V(74,4E,BC,37), V(FC,82,CA,A6), V(E0,90,D0,B0), V(33,A7,D8,15), \
    V(F1,04,98,4A), V(41,EC,DA,F7), V(7F,CD,50,0E), V(17,91,F6,2F), \
    V(76,4D,D6,8D), V(43,EF,B0,4D), V(CC,AA,4D,54), V(E4,96,04,DF), \
    V(9E,D1,B5,E3), V(4C,6A,88,1B), V(C1,2C,1F,B8), V(46,65,51,7F), \
    V(9D,5E,EA,04), V(01,8C,35,5D), V(FA,87,74,73), V(FB,0B,41,2E), \
    V(B3,67,1D,5A), V(92,DB,D2,52), V(E9,10,56,33), V(6D,D6,47,13), \
    V(9A,D7,61,8C), V(37,A1,0C,7A), V(59,F8,14,8E), V(EB,13,3C,89), \
    V(CE,A9,27,EE), V(B7,61,C9,35), V(E1,1C,E5,ED), V(7A,47,B1,3C), \
    V(9C,D2,DF,59), V(55,F2,73,3F), V(18,14,CE,79), V(73,C7,37,BF), \
    V(53,F7,CD,EA), V(5F,FD,AA,5B), V(DF,3D,6F,14), V(78,44,DB,86), \
    V(CA,AF,F3,81), V(B9,68,C4,3E), V(38,24,34,2C), V(C2,A3,40,5F), \
    V(16,1D,C3,72), V(BC,E2,25,0C), V(28,3C,49,8B), V(FF,0D,95,41), \
    V(39,A8,01,71), V(08,0C,B3,DE), V(D8,B4,E4,9C), V(64,56,C1,90), \
    V(7B,CB,84,61), V(D5,32,B6,70), V(48,6C,5C,74), V(D0,B8,57,42)

#define V(a,b,c,d) 0x##a##b##c##d
static const uint32 RT0[256] = { RT };
#undef V

#define V(a,b,c,d) 0x##d##a##b##c
static const uint32 RT1[256] = { RT };
#undef V

#define V(a,b,c,d) 0x##c##d##a##b
static const uint32 RT2[256] = { RT };
#undef V

#define V(a,b,c,d) 0x##b##c##d##a
static const uint32 RT3[256] = { RT };
#undef V

#undef RT

/*
 * Round constants
 */
static const uint32 RCON[10] =
{
    0x01000000, 0x02000000, 0x04000000, 0x08000000,
    0x10000000, 0x20000000, 0x40000000, 0x80000000,
    0x1B000000, 0x36000000
};

static void aes_gen_tables( void ) {}

#endif

/*
 * Decryption key schedule tables
 */
static uint32 KT0[256];
static uint32 KT1[256];
static uint32 KT2[256];
static uint32 KT3[256];

/*
 * AES key schedule
 */
void aes_set_key( aes_context *ctx, uint8 *key, int keysize )
{
    int i;
    uint32 *RK, *SK;
    static int ft_init = 0;
    static int kt_init = 0;

    if( ft_init == 0 )
    {
        aes_gen_tables();

        ft_init = 1;
    }

    switch( keysize )
    {
        case 128: ctx->nr = 10; break;
        case 192: ctx->nr = 12; break;
        case 256: ctx->nr = 14; break;
        default : return;
    }

    RK = ctx->erk;

    for( i = 0; i < (keysize >> 5); i++ )
    {
        GET_UINT32_BE( RK[i], key, i << 2 );
    }

    /*
     * setup encryption round keys
     */
    switch( ctx->nr )
    {
    case 10:

        for( i = 0; i < 10; i++, RK += 4 )
        {
            RK[4]  = RK[0] ^ RCON[i] ^
                ( FSb[ (uint8) ( RK[3] >> 16 ) ] << 24 ) ^
                ( FSb[ (uint8) ( RK[3] >>  8 ) ] << 16 ) ^
                ( FSb[ (uint8) ( RK[3]       ) ] <<  8 ) ^
                ( FSb[ (uint8) ( RK[3] >> 24 ) ]       );

            RK[5]  = RK[1] ^ RK[4];
            RK[6]  = RK[2] ^ RK[5];
            RK[7]  = RK[3] ^ RK[6];
        }
        break;

    case 12:

        for( i = 0; i < 8; i++, RK += 6 )
        {
            RK[6]  = RK[0] ^ RCON[i] ^
                ( FSb[ (uint8) ( RK[5] >> 16 ) ] << 24 ) ^
                ( FSb[ (uint8) ( RK[5] >>  8 ) ] << 16 ) ^
                ( FSb[ (uint8) ( RK[5]       ) ] <<  8 ) ^
                ( FSb[ (uint8) ( RK[5] >> 24 ) ]       );

            RK[7]  = RK[1] ^ RK[6];
            RK[8]  = RK[2] ^ RK[7];
            RK[9]  = RK[3] ^ RK[8];
            RK[10] = RK[4] ^ RK[9];
            RK[11] = RK[5] ^ RK[10];
        }
        break;

    case 14:

        for( i = 0; i < 7; i++, RK += 8 )
        {
            RK[8]  = RK[0] ^ RCON[i] ^
                ( FSb[ (uint8) ( RK[7] >> 16 ) ] << 24 ) ^
                ( FSb[ (uint8) ( RK[7] >>  8 ) ] << 16 ) ^
                ( FSb[ (uint8) ( RK[7]       ) ] <<  8 ) ^
                ( FSb[ (uint8) ( RK[7] >> 24 ) ]       );

            RK[9]  = RK[1] ^ RK[8];
            RK[10] = RK[2] ^ RK[9];
            RK[11] = RK[3] ^ RK[10];

            RK[12] = RK[4] ^
                ( FSb[ (uint8) ( RK[11] >> 24 ) ] << 24 ) ^
                ( FSb[ (uint8) ( RK[11] >> 16 ) ] << 16 ) ^
                ( FSb[ (uint8) ( RK[11] >>  8 ) ] <<  8 ) ^
                ( FSb[ (uint8) ( RK[11]       ) ]       );

            RK[13] = RK[5] ^ RK[12];
            RK[14] = RK[6] ^ RK[13];
            RK[15] = RK[7] ^ RK[14];
        }
        break;

    default:

        break;
    }

    /*
     * setup decryption round keys
     */
    if( kt_init == 0 )
    {
        for( i = 0; i < 256; i++ )
        {
            KT0[i] = RT0[ FSb[i] ];
            KT1[i] = RT1[ FSb[i] ];
            KT2[i] = RT2[ FSb[i] ];
            KT3[i] = RT3[ FSb[i] ];
        }

        kt_init = 1;
    }

    SK = ctx->drk;

    *SK++ = *RK++;
    *SK++ = *RK++;
    *SK++ = *RK++;
    *SK++ = *RK++;

    for( i = 1; i < ctx->nr; i++ )
    {
        RK -= 8;

        *SK++ = KT0[ (uint8) ( *RK >> 24 ) ] ^
                KT1[ (uint8) ( *RK >> 16 ) ] ^
                KT2[ (uint8) ( *RK >>  8 ) ] ^
                KT3[ (uint8) ( *RK       ) ]; RK++;

        *SK++ = KT0[ (uint8) ( *RK >> 24 ) ] ^
                KT1[ (uint8) ( *RK >> 16 ) ] ^
                KT2[ (uint8) ( *RK >>  8 ) ] ^
                KT3[ (uint8) ( *RK       ) ]; RK++;

        *SK++ = KT0[ (uint8) ( *RK >> 24 ) ] ^
                KT1[ (uint8) ( *RK >> 16 ) ] ^
                KT2[ (uint8) ( *RK >>  8 ) ] ^
                KT3[ (uint8) ( *RK       ) ]; RK++;

        *SK++ = KT0[ (uint8) ( *RK >> 24 ) ] ^
                KT1[ (uint8) ( *RK >> 16 ) ] ^
                KT2[ (uint8) ( *RK >>  8 ) ] ^
                KT3[ (uint8) ( *RK       ) ]; RK++;
    }

    RK -= 8;

    *SK++ = *RK++;
    *SK++ = *RK++;
    *SK++ = *RK++;
    *SK++ = *RK++;
}

/**