Challenge for SlashRoot CTF Final at STIKOM Bali Jimbaran hosted by UKM KSL
Nevar pievienot vairāk kā 25 tēmas Tēmai ir jāsākas ar burtu vai ciparu, tā var saturēt domu zīmes ('-') un var būt līdz 35 simboliem gara.
 
 

104 rindas
2.3 KiB

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <setjmp.h>
/*
* SIGFPE bisa nempel di CPU, perlu dicari solusi
* Test openssl lewat socat
*/
void signal_handler(int sig)
{
signal(SIGFPE, signal_handler);
system("/bin/sh");
exit(1);
}
int main(int argc, char const *argv[])
{
int i_a = 0;
int i_b = 0;
int total = 0;
setvbuf(stdin, NULL, _IONBF, 0);
setvbuf(stdout, NULL, _IONBF, 0);
setvbuf(stderr, NULL, _IONBF, 0);
signal(SIGFPE, signal_handler);
puts("Welcome to Online Calculator v3.1");
puts("");
puts("Operator supported: + - * /");
puts("ex: 2 + 2");
puts("ex: 2 + a //'a' to use last results");
puts("");
puts("------------------------------------");
while (1)
{
char c_a[11] = "";
char c_b[11] = "";
char opt = 0;
printf(">");
if (scanf("%10s %c %10s", c_a, &opt, c_b) < 3)
{
puts("Failed to parse expression!");
return 0;
}
else
{
int r1_a = sscanf(c_a, "%d", &i_a);
int r2_a = strcmp("a", c_a) == 0;
int r1_b = sscanf(c_b, "%d", &i_b);
int r2_b = strcmp("a", c_b) == 0;
if ((i_b == 0 && r2_a) && opt == '/')
{
puts("Floating point exception (core dumped)");
return 0;
}
if (r2_a)
{
i_a = total;
}
if (r2_b)
{
i_b = total;
}
if ((r1_a || r2_a) && (r1_b || r2_b))
{
switch (opt)
{
case '+':
total = i_a + i_b;
break;
case '-':
total = i_a - i_b;
break;
case '*':
total = i_a * i_b;
break;
case '/':
total = i_a / i_b;
break;
default:
puts("Unknown operator!");
return 0;
}
printf("=%d\n", total);
}
else
{
puts("Failed to parse operand!");
return 0;
}
}
}
return 0;
}