// ccured wrappers
int dn_expand_wrapper(const u_char *msg, const u_char *eomorig,
const u_char *comp_dn, char *exp_dn, int length) {
__write_at_least(exp_dn, length);
__verify_nul(comp_dn);
return ( dn_expand(__ptrof(msg), __ptrof(eomorig), __ptrof(comp_dn),
__ptrof(exp_dn), length) );
}
/* This code is from a custom allocator that allocates a header before the
* actual memory block */
int main() {
struct header {
int one;
int *two;
int three;
} *h;
char *p;
// We allocate 3 chars but with a header
char* v = (char*)malloc(sizeof(struct header) + 4);
#ifndef CCURED
h = (struct header*)v; // Will check here that there is enough space in p
h->one = 5; // Write something to the header
p = (char*)(h + 1); // Skip the header, but this makes h SEQ
#else
// In the CCURED version we have to play some tricks
// Make sure h is not SEQ, so, don't do h + 1
// We want h to be SAFE. If header did not contain pointers we could do:
// h = (struct header*)v;
// But since header contains pointers, it is not SAFE to cast from a
// char-ptr to a header-ptr. trusted_cast wants its both ends to have
// the same kind, which would make h SEQ. We use __ptrof instead.
// But be careful how you use h in the future, because if you make it
// SEQ, you will need __ptrof_qq, which does not exist!
h = (struct header*)__ptrof(v);
h->one = 5;
// Use v to compute p, not h. This way h can stay SAFE.
p = v + sizeof(struct header);
#endif
// And we need the result to be SEQ
p ++;
p --;
return 0;
}