blob: ca360c0bc9153afd6205c55d79bf6f29f9dd5b44 [file] [log] [blame]
// Compile with /home/llozano/local2/proj/vtable/gcc-root/usr/local/bin/g++ -m32 -fvtable-verify=std -fpic -rdynamic -Wl,-R,/home/llozano/local2/proj/vtable/gcc-root/usr/local/lib32:./lib32 -I/home/llozano/local2/proj/vtable/vt2/gcc-4_6-mobile-vtable-security//libstdc++-v3/libsupc++ temp_deriv.cc -O0 -ldl -lpthread -Wl,--whole-archive,-lvtv_init,--no-whole-archive,-z,relro -DTPID=0 -g
// Look at assembly with: objdump -drl a.out
#include <dlfcn.h>
#include <assert.h>
extern "C" int printf(const char *, ...);
static int counter = 0;
template <int i> struct base
{
virtual void inc() { counter += i; }
};
template <int i> struct derived: base<i>
{
virtual void inc() { counter += (10*i); }
};
// We don't use this class. It is just here so that the
// compiler does not devirtualize calls to derived::inc()
template <int i> struct derived2: derived<i>
{
virtual void inc() { counter += (20*i); }
};
static base<TPID> * bp = new base<TPID>();
static derived<TPID> * dp = new derived<TPID>();
static base<TPID> * dbp = new derived<TPID>();
// Given 2 pointers to C++ objects (non PODs), exchange the pointers to vtable
void exchange_vtptr(void * object1_ptr, void * object2_ptr)
{
void ** object1_vtptr_ptr = (void **)object1_ptr;
void ** object2_vtptr_ptr = (void **)object2_ptr;
void * object1_vtptr = *object1_vtptr_ptr;
void * object2_vtptr = *object2_vtptr_ptr;
*object1_vtptr_ptr = object2_vtptr;
*object2_vtptr_ptr = object1_vtptr;
}
main()
{
int prev_counter;
exchange_vtptr(bp, dp);
exchange_vtptr(bp, dp);
exchange_vtptr(bp, dbp);
exchange_vtptr(bp, dbp);
counter = 0;
bp->inc();
dp->inc();
dbp->inc();
assert(counter == (TPID + 10*TPID + 10*TPID));
prev_counter = counter;
exchange_vtptr(bp, dp);
bp->inc(); // This one should succeed but it is calling the wrong member
assert(counter == (prev_counter + 10*TPID));
printf("Pass first attack!\n");
dp->inc();
printf("TPDI=%d counter %d\n", TPID, counter);
printf("Pass second attack!\n");
}