pfil4_wrapper
static int pfil4_wrapper(void *, struct mbuf **, struct ifnet *, int);
error = pfil_add_hook((void *)pfil4_wrapper, NULL,
pfil_remove_hook(pfil4_wrapper, NULL, PFIL_IN|PFIL_OUT, ph_inet);
pfil_remove_hook((void *)pfil4_wrapper, NULL,