a student
I know nothing about C++...got this exercise in a course about security...have been trying to understand this problem for last 3 hours...still in vain...can someone give me a hint??
#include <iostream>
main()
{
char command[40]; // Send command to
int time_of_day; // Avoid replay attack?
const bool ever = 1;
for ( ;ever; )
{
cin >> time_of_day >> command;
cout << "Command was " << command << " at time " << time_of_day << endl;
}
}
if we try input:
13 report
13 shoot-to-kill
15 shoot only if they shoot first
12:00 fire
how can someone perform a denial of service attack on this server? This same error was present in NT4, prior to service pack 2. This problem is difficult to fix with the C++ stream library, but easy to fix with C's I/O library:
#include <stdio.h>
#define ever 1
main()
{ char command[40]; // Send command to
int time_of_day; // Avoid replay attack?
for ( ;ever; )
{
scanf("%d %[^\n]",&time_of_day,command);
printf("Command %s at time %d\n",command,time_of_day);
}
}
The regular expression matcher %[^\n] means `match any object consisting of any character up to end of line'.
Why is it safer now?
|
