#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/mbuf.h>
#include <sys/proc.h>
#include <sys/socket.h>
/* #include <netinet/in_systm.h> */
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <net/pfil.h>
#include <sys/lkm.h>
#include <net/pfvar.h>

dev_type_open(pfopen);
dev_type_close(pfclose);
dev_type_ioctl(pfioctl);
const struct cdevsw pf_cdevsw = {
	pfopen, pfclose, noread, nowrite, pfioctl,
	nostop, notty, nopoll, nommap, nokqfilter, D_TTY
};
static int pfil_hooked = 0;

MOD_DEV("pf", "pf", NULL, -1, &pf_cdevsw, -1);

extern int pf_test(int, struct ifnet *, struct mbuf **);

static int
pf_hook(void *arg, struct mbuf **mp, struct ifnet *ifp, int dir)
{
        struct ip       *h;
        int             rval;

        /*
         * Unlike OpenBSD, we keep those in network byte order.
         * It's easier to make a temporary swap instead of changing
         * all the pf code.
         */
        h = mtod(*mp, struct ip *);
        NTOHS(h->ip_len);
        NTOHS(h->ip_off);
        rval = pf_test(dir, ifp, mp);
        if (*mp != NULL) {
                h = mtod(*mp, struct ip *);
                HTONS(h->ip_len);
                HTONS(h->ip_off);
        }
        return (rval);
}

int
pfmodule_lkmentry(struct lkm_table *lkmtp, int cmd, int ver)
{
	DISPATCH(lkmtp, cmd, ver, pfmodule_lkmload, pfmodule_lkmunload,
	    lkm_nofunc);
}

int
pfmodule_lkmload(struct lkm_table *lkmtp, int cmd)
{
	struct pfil_head	*ph;

	if (pfil_hooked) {
		printf("Error: pflkm already loaded\n");
		return (EEXIST);
	}
	if (lkmexists(lkmtp))
		return (EEXIST);

	ph = pfil_head_get(PFIL_TYPE_AF, AF_INET);
	if (ph == NULL) {
		printf("Error: couldn't find AF_INET pfil head.\n"
		    "Make sure you compiled your kernel with PFIL_HOOKS.\n");
		return (EINVAL);
	}
	pfil_add_hook(pf_hook, NULL, PFIL_ALL, ph);
	pfil_hooked = 1;
	/* XXX look for AF_INET6 head and install hook there, too */
	pfattach(1);
	pflogattach(1);
	pfsyncattach(1);
	return (0);
}

int
pfmodule_lkmunload(struct lkm_table *lkmtp, int cmd)
{
	struct pfil_head	*ph;

	if (pfil_hooked) {
		ph = pfil_head_get(PFIL_TYPE_AF, AF_INET);
		if (ph == NULL)
			panic("Couldn't get pfil inet head");
		else
			pfil_remove_hook(pf_hook, NULL, PFIL_ALL, ph);
		/* XXX look for AF_INET6 head and remove hook ifdef INET6 */
		pfil_hooked = 0;
	}
	pfsyncdetach(1);
	pflogdetach(1);
	pfdetach(1);
	return (0);
}