pfil_head_get
ph_inet = pfil_head_get(PFIL_TYPE_AF, (void *)AF_INET);
ph_inet6 = pfil_head_get(PFIL_TYPE_AF, (void *)AF_INET6);
ph_inet = pfil_head_get(PFIL_TYPE_AF, (void *)AF_INET);
ph_inet6 = pfil_head_get(PFIL_TYPE_AF, (void *)AF_INET6);
if ((npf_ph_ether = pfil_head_get(PFIL_TYPE_IFNET, ifp)) == NULL) {
npf_ph_if = pfil_head_get(PFIL_TYPE_IFNET, 0);
npf_ph_inet = pfil_head_get(PFIL_TYPE_AF, (void *)AF_INET);
npf_ph_inet6 = pfil_head_get(PFIL_TYPE_AF, (void *)AF_INET6);
if (pfil_head_get(type, key)) {
pfil_head_t * pfil_head_get(int, void *);