// gcc -g -O0 -m32 -std=c99 control.c
#include
#include
#include
struct User
{
char name[8];
bool is_admin;
};
int main()
{
struct User user = {0};
printf("Enter user name:\n");
gets(user.name);
if(strcmp(user.name, "admin") == 0)
user.is_admin = true;
if(user.is_admin)
printf("Welcome back administrator!\n");
else
printf("Meh, hello %s. I was hoping for the administrator.\n", user.name);
return 0;
}
Running Flawfinder on the source code file yields the following output.
$ flawfinder basic/control.c
Flawfinder version 1.31, (C) 2001-2014 David A. Wheeler.
Number of rules (primarily dangerous function names) in C/C++ ruleset: 169
Examining basic/control.c
FINAL RESULTS:
basic/control.c:17: [5] (buffer) gets:
Does not check for buffer overflows (CWE-120, CWE-20). Use fgets() instead.
basic/control.c:8: [2] (buffer) char:
Statically-sized arrays can be improperly restricted, leading to potential
overflows or other issues (CWE-119:CWE-120). Perform bounds checking, use
functions that limit length, or ensure that the size is larger than the
maximum possible length.
ANALYSIS SUMMARY:
Hits = 2
Lines analyzed = 27 in approximately 0.00 seconds (6493 lines/second)
Physical Source Lines of Code (SLOC) = 21
Hits@level = [0] 0 [1] 0 [2] 1 [3] 0 [4] 0 [5] 1
Hits@level+ = [0+] 2 [1+] 2 [2+] 2 [3+] 1 [4+] 1 [5+] 1
Hits/KSLOC@level+ = [0+] 95.2381 [1+] 95.2381 [2+] 95.2381 [3+] 47.619 [4+] 47.619 [5+] 47.619
Minimum risk level = 1
Not every hit is necessarily a security vulnerability.
There may be other security vulnerabilities; review your code!
See 'Secure Programming for Linux and Unix HOWTO'
(http://www.dwheeler.com/secure-programs) for more information.
Flawfinder reports the obviously dangerous usage of ''gets()''. Additionally, the tool recommends to check the bounds of the statically allocated array.
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