AES128 how-to using GCC and Intel AES-NI

aes-ni.c

#include <stdint.h>     //for int8_t
#include <wmmintrin.h>  //for intrinsics for AES-NI
//compile using gcc and following arguments: -g;-O0;-Wall;-msse2;-msse;-march=native;-maes

//internal stuff

//macros
#define DO_ENC_BLOCK(m,k) \
	do{\
        m = _mm_xor_si128       (m, k[ 0]); \
        m = _mm_aesenc_si128    (m, k[ 1]); \
        m = _mm_aesenc_si128    (m, k[ 2]); \
        m = _mm_aesenc_si128    (m, k[ 3]); \
        m = _mm_aesenc_si128    (m, k[ 4]); \
        m = _mm_aesenc_si128    (m, k[ 5]); \
        m = _mm_aesenc_si128    (m, k[ 6]); \
        m = _mm_aesenc_si128    (m, k[ 7]); \
        m = _mm_aesenc_si128    (m, k[ 8]); \
        m = _mm_aesenc_si128    (m, k[ 9]); \
        m = _mm_aesenclast_si128(m, k[10]);\
    }while(0)

#define AES_128_key_exp(k, rcon) aes_128_key_expansion(k, _mm_aeskeygenassist_si128(k, rcon))

static __m128i aes_128_key_expansion(__m128i key, __m128i keygened){
	keygened = _mm_shuffle_epi32(keygened, _MM_SHUFFLE(3,3,3,3));
	key = _mm_xor_si128(key, _mm_slli_si128(key, 4));
	key = _mm_xor_si128(key, _mm_slli_si128(key, 4));
	key = _mm_xor_si128(key, _mm_slli_si128(key, 4));
	return _mm_xor_si128(key, keygened);
}

//public API
void aes128_load_key(int8_t *enc_key, __m128i *key_schedule){
    key_schedule[0] = _mm_loadu_si128((const __m128i*) enc_key);
	key_schedule[1]  = AES_128_key_exp(key_schedule[0], 0x01);
	key_schedule[2]  = AES_128_key_exp(key_schedule[1], 0x02);
	key_schedule[3]  = AES_128_key_exp(key_schedule[2], 0x04);
	key_schedule[4]  = AES_128_key_exp(key_schedule[3], 0x08);
	key_schedule[5]  = AES_128_key_exp(key_schedule[4], 0x10);
	key_schedule[6]  = AES_128_key_exp(key_schedule[5], 0x20);
	key_schedule[7]  = AES_128_key_exp(key_schedule[6], 0x40);
	key_schedule[8]  = AES_128_key_exp(key_schedule[7], 0x80);
	key_schedule[9]  = AES_128_key_exp(key_schedule[8], 0x1B);
	key_schedule[10] = AES_128_key_exp(key_schedule[9], 0x36);
}

void aes128_enc(int8_t *plainText,int8_t *cipherText, __m128i *key_schedule){
    __m128i m = _mm_loadu_si128((__m128i *) plainText);

    DO_ENC_BLOCK(m,key_schedule);

    _mm_storeu_si128((__m128i *) cipherText, m);
}