Function pfil_run_hooks

freebsd/net/pfil.c:163–199

* pfil_run_hooks() runs the specified packet filter hook chain. */

 * pfil_run_hooks() runs the specified packet filter hook chain.
 */
int
pfil_run_hooks(struct pfil_head *head, pfil_packet_t p, struct ifnet *ifp,
    int flags, struct inpcb *inp)
{
	pfil_chain_t *pch;
	struct pfil_link *link;
	pfil_return_t rv;
	bool realloc = false;

	NET_EPOCH_ASSERT();

	if (PFIL_DIR(flags) == PFIL_IN)
		pch = &head->head_in;
	else if (__predict_true(PFIL_DIR(flags) == PFIL_OUT))
		pch = &head->head_out;
	else
		panic("%s: bogus flags %d", __func__, flags);

	rv = PFIL_PASS;
	CK_STAILQ_FOREACH(link, pch, link_chain) {
		if ((flags & PFIL_MEMPTR) && !(link->link_flags & PFIL_MEMPTR))
			rv = pfil_fake_mbuf(link->link_func, &p, ifp, flags,
			    link->link_ruleset, inp);
		else
			rv = (*link->link_func)(p, ifp, flags,
			    link->link_ruleset, inp);
		if (rv == PFIL_DROPPED || rv == PFIL_CONSUMED)
			break;
		else if (rv == PFIL_REALLOCED) {
			flags &= ~(PFIL_MEMPTR | PFIL_LENMASK);
			realloc = true;
		}
	}
	if (realloc && rv == PFIL_PASS)
		rv = PFIL_REALLOCED;
	return (rv);
}

/*
 * pfil_head_register() registers a pfil_head with the packet filter hook