1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
|
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <openssl/md5.h>
unsigned char secret[10];
unsigned char target[10];
unsigned char result[MD5_DIGEST_LENGTH];
void hash(int i) {
char num[12];
sprintf(num, "%d", i);
char str[22] = "";
strcat(str, secret);
strcat(str, num);
MD5(str, strlen(str), result);
}
int tohex() {
int i, dg = 0;
for(i = 0; i < 4; i++) {
dg <<= 8;
dg += result[i];
}
return dg;
}
int check(int len) {
unsigned char str[8];
int dg = tohex();
sprintf(str, "%08x", dg);
return strncmp(str, target, len) == 0;
}
int main() {
int i = 1, got5 = 0, got6 = 0;
scanf("%s", secret);
scanf("%s", target);
while(!(got5 && got6)) {
hash(i);
if(!got5 && check(5)) {
got5 = 1;
printf("Lowest number for 5-zeroes hash: %d\n", i);
}
if(!got6 && check(6)) {
got6 = 1;
printf("Lowest number for 6-zeroes hash: %d\n", i);
}
i++;
}
return 0;
}
|
