root/sys/dist/pf/net/pf.c
/*      $NetBSD: pf.c,v 1.87 2022/11/04 09:01:53 ozaki-r Exp $  */
/*      $OpenBSD: pf.c,v 1.552.2.1 2007/11/27 16:37:57 henning Exp $ */

/*
 * Copyright (c) 2001 Daniel Hartmeier
 * Copyright (c) 2002,2003 Henning Brauer
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *    - Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    - Redistributions in binary form must reproduce the above
 *      copyright notice, this list of conditions and the following
 *      disclaimer in the documentation and/or other materials provided
 *      with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * Effort sponsored in part by the Defense Advanced Research Projects
 * Agency (DARPA) and Air Force Research Laboratory, Air Force
 * Materiel Command, USAF, under agreement number F30602-01-2-0537.
 *
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: pf.c,v 1.87 2022/11/04 09:01:53 ozaki-r Exp $");

#include "pflog.h"

#include "pfsync.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/filio.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/kernel.h>
#include <sys/time.h>
#include <sys/pool.h>
#include <sys/proc.h>
#include <sys/rwlock.h>
#ifdef __NetBSD__
#include <sys/kthread.h>
#include <sys/kauth.h>
#endif /* __NetBSD__ */

#include <net/if.h>
#include <net/if_types.h>
#include <net/bpf.h>
#include <net/route.h>
#ifndef __NetBSD__
#include <net/radix_mpath.h>
#endif /* !__NetBSD__ */

#include <netinet/in.h>
#ifdef __NetBSD__
#include <netinet/in_offload.h>
#endif /* __NetBSD__ */
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/tcp.h>
#include <netinet/tcp_seq.h>
#include <netinet/udp.h>
#include <netinet/ip_icmp.h>
#include <netinet/in_pcb.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
#include <netinet/udp_var.h>
#include <netinet/icmp_var.h>
#ifndef __NetBSD__
#include <netinet/if_ether.h>
#else
#include <net/if_ether.h>
#endif /* __NetBSD__ */

#ifndef __NetBSD__
#include <dev/rndvar.h>
#else
#include <sys/cprng.h>
#endif /* __NetBSD__ */

#include <net/pfvar.h>
#include <net/if_pflog.h>

#if NPFSYNC > 0
#include <net/if_pfsync.h>
#endif /* NPFSYNC > 0 */

#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#ifdef __NetBSD__
#include <netinet6/in6_pcb.h>
#endif /* __NetBSD__ */
#include <netinet/icmp6.h>
#include <netinet6/nd6.h>
#endif /* INET6 */

#ifdef __NetBSD__
#include <netinet/tcp_rndiss.h>
#endif /* __NetBSD__ */


#define DPFPRINTF(n, x) if (pf_status.debug >= (n)) printf x

/*
 * Global variables
 */

/* state tables */
struct pf_state_tree_lan_ext     pf_statetbl_lan_ext;
struct pf_state_tree_ext_gwy     pf_statetbl_ext_gwy;

struct pf_altqqueue      pf_altqs[2];
struct pf_palist         pf_pabuf;
struct pf_altqqueue     *pf_altqs_active;
struct pf_altqqueue     *pf_altqs_inactive;
struct pf_status         pf_status;

u_int32_t                ticket_altqs_active;
u_int32_t                ticket_altqs_inactive;
int                      altqs_inactive_open;
u_int32_t                ticket_pabuf;

struct pf_anchor_stackframe {
        struct pf_ruleset                       *rs;
        struct pf_rule                          *r;
        struct pf_anchor_node                   *parent;
        struct pf_anchor                        *child;
} pf_anchor_stack[64];

struct pool              pf_src_tree_pl, pf_rule_pl, pf_pooladdr_pl;
struct pool              pf_state_pl, pf_state_key_pl;
struct pool              pf_altq_pl;

void                     pf_print_host(struct pf_addr *, u_int16_t, u_int8_t);

void                     pf_init_threshold(struct pf_threshold *, u_int32_t,
                            u_int32_t);
void                     pf_add_threshold(struct pf_threshold *);
int                      pf_check_threshold(struct pf_threshold *);

void                     pf_change_ap(struct pf_addr *, u_int16_t *,
                            u_int16_t *, u_int16_t *, struct pf_addr *,
                            u_int16_t, u_int8_t, sa_family_t);
int                      pf_modulate_sack(struct mbuf *, int, struct pf_pdesc *,
                            struct tcphdr *, struct pf_state_peer *);
#ifdef INET6
void                     pf_change_a6(struct pf_addr *, u_int16_t *,
                            struct pf_addr *, u_int8_t);
#endif /* INET6 */
void                     pf_change_icmp(struct pf_addr *, u_int16_t *,
                            struct pf_addr *, struct pf_addr *, u_int16_t,
                            u_int16_t *, u_int16_t *, u_int16_t *,
                            u_int16_t *, u_int8_t, sa_family_t);
void                     pf_send_tcp(const struct pf_rule *, sa_family_t,
                            const struct pf_addr *, const struct pf_addr *,
                            u_int16_t, u_int16_t, u_int32_t, u_int32_t,
                            u_int8_t, u_int16_t, u_int16_t, u_int8_t, int,
                            u_int16_t, struct ether_header *, struct ifnet *);
void                     pf_send_icmp(struct mbuf *, u_int8_t, u_int8_t,
                            sa_family_t, struct pf_rule *);
struct pf_rule          *pf_match_translation(struct pf_pdesc *, struct mbuf *,
                            int, int, struct pfi_kif *,
                            struct pf_addr *, u_int16_t, struct pf_addr *,
                            u_int16_t, int);
struct pf_rule          *pf_get_translation(struct pf_pdesc *, struct mbuf *,
                            int, int, struct pfi_kif *, struct pf_src_node **,
                            struct pf_addr *, u_int16_t,
                            struct pf_addr *, u_int16_t,
                            struct pf_addr *, u_int16_t *);
void                     pf_attach_state(struct pf_state_key *,
                            struct pf_state *, int);
void                     pf_detach_state(struct pf_state *, int);
int                      pf_test_rule(struct pf_rule **, struct pf_state **,
                            int, struct pfi_kif *, struct mbuf *, int,
                            void *, struct pf_pdesc *, struct pf_rule **,
                            struct pf_ruleset **, struct ifqueue *);
int                      pf_test_fragment(struct pf_rule **, int,
                            struct pfi_kif *, struct mbuf *, void *,
                            struct pf_pdesc *, struct pf_rule **,
                            struct pf_ruleset **);
int                      pf_test_state_tcp(struct pf_state **, int,
                            struct pfi_kif *, struct mbuf *, int,
                            void *, struct pf_pdesc *, u_short *);
int                      pf_test_state_udp(struct pf_state **, int,
                            struct pfi_kif *, struct mbuf *, int,
                            void *, struct pf_pdesc *);
int                      pf_test_state_icmp(struct pf_state **, int,
                            struct pfi_kif *, struct mbuf *, int,
                            void *, struct pf_pdesc *, u_short *);
int                      pf_test_state_other(struct pf_state **, int,
                            struct pfi_kif *, struct pf_pdesc *);
int                      pf_match_tag(struct mbuf *, struct pf_rule *, int *);
void                     pf_step_into_anchor(int *, struct pf_ruleset **, int,
                            struct pf_rule **, struct pf_rule **,  int *);
int                      pf_step_out_of_anchor(int *, struct pf_ruleset **,
                             int, struct pf_rule **, struct pf_rule **,
                             int *);
void                     pf_hash(const struct pf_addr *, struct pf_addr *,
                            struct pf_poolhashkey *, sa_family_t);
int                      pf_map_addr(u_int8_t, struct pf_rule *,
                            const struct pf_addr *, struct pf_addr *,
                            struct pf_addr *, struct pf_src_node **);
int                      pf_get_sport(sa_family_t, u_int8_t, struct pf_rule *,
                            struct pf_addr *, struct pf_addr *, u_int16_t,
                            struct pf_addr *, u_int16_t*, u_int16_t, u_int16_t,
                            struct pf_src_node **);
void                     pf_route(struct mbuf **, struct pf_rule *, int,
                            struct ifnet *, struct pf_state *,
                            struct pf_pdesc *);
void                     pf_route6(struct mbuf **, struct pf_rule *, int,
                            struct ifnet *, struct pf_state *,
                            struct pf_pdesc *);
int                      pf_socket_lookup(int, struct pf_pdesc *);
u_int8_t                 pf_get_wscale(struct mbuf *, int, u_int16_t,
                            sa_family_t);
u_int16_t                pf_get_mss(struct mbuf *, int, u_int16_t,
                            sa_family_t);
u_int16_t                pf_calc_mss(struct pf_addr *, sa_family_t,
                                u_int16_t);
void                     pf_set_rt_ifp(struct pf_state *,
                            struct pf_addr *);
#ifdef __NetBSD__
int                      pf_check_proto_cksum(struct mbuf *, int, int, int,
                            u_int8_t, sa_family_t);
#else
int                      pf_check_proto_cksum(struct mbuf *, int, int,
                            u_int8_t, sa_family_t);
#endif /* !__NetBSD__ */
int                      pf_addr_wrap_neq(struct pf_addr_wrap *,
                            struct pf_addr_wrap *);
struct pf_state         *pf_find_state(struct pfi_kif *,
                            struct pf_state_key_cmp *, u_int8_t);
int                      pf_src_connlimit(struct pf_state **);
void                     pf_stateins_err(const char *, struct pf_state *,
                            struct pfi_kif *);
int                      pf_check_congestion(struct ifqueue *);

extern struct pool pfr_ktable_pl;
extern struct pool pfr_kentry_pl;

extern int pf_state_lock;

struct pf_pool_limit pf_pool_limits[PF_LIMIT_MAX] = {
        { &pf_state_pl, PFSTATE_HIWAT },
        { &pf_src_tree_pl, PFSNODE_HIWAT },
        { &pf_frent_pl, PFFRAG_FRENT_HIWAT },
        { &pfr_ktable_pl, PFR_KTABLE_HIWAT },
        { &pfr_kentry_pl, PFR_KENTRY_HIWAT }
};

#define STATE_LOOKUP()                                                  \
        do {                                                            \
                if (pf_state_lock) {                \
                        *state = NULL;                          \
                        return (PF_DROP);                       \
                }                                                               \
                if (direction == PF_IN)                                 \
                        *state = pf_find_state(kif, &key, PF_EXT_GWY);  \
                else                                                    \
                        *state = pf_find_state(kif, &key, PF_LAN_EXT);  \
                if (*state == NULL || (*state)->timeout == PFTM_PURGE)  \
                        return (PF_DROP);                               \
                if (direction == PF_OUT &&                              \
                    (((*state)->rule.ptr->rt == PF_ROUTETO &&           \
                      (*state)->rule.ptr->direction == PF_OUT) ||       \
                     ((*state)->rule.ptr->rt == PF_REPLYTO &&           \
                      (*state)->rule.ptr->direction == PF_IN)) &&       \
                    (*state)->rt_kif != NULL &&                         \
                    (*state)->rt_kif != kif)                            \
                        return (PF_PASS);                               \
        } while (0)

#define STATE_TRANSLATE(sk) \
        (sk)->lan.addr.addr32[0] != (sk)->gwy.addr.addr32[0] || \
        ((sk)->af == AF_INET6 && \
        ((sk)->lan.addr.addr32[1] != (sk)->gwy.addr.addr32[1] || \
        (sk)->lan.addr.addr32[2] != (sk)->gwy.addr.addr32[2] || \
        (sk)->lan.addr.addr32[3] != (sk)->gwy.addr.addr32[3])) || \
        (sk)->lan.port != (sk)->gwy.port

#define BOUND_IFACE(r, k) \
        ((r)->rule_flag & PFRULE_IFBOUND) ? (k) : pfi_all

#define STATE_INC_COUNTERS(s)                           \
        do {                                            \
                s->rule.ptr->states++;                  \
                if (s->anchor.ptr != NULL)              \
                        s->anchor.ptr->states++;        \
                if (s->nat_rule.ptr != NULL)            \
                        s->nat_rule.ptr->states++;      \
        } while (0)

#define STATE_DEC_COUNTERS(s)                           \
        do {                                            \
                if (s->nat_rule.ptr != NULL)            \
                        s->nat_rule.ptr->states--;      \
                if (s->anchor.ptr != NULL)              \
                        s->anchor.ptr->states--;        \
                s->rule.ptr->states--;                  \
        } while (0)

static __inline int pf_src_compare(struct pf_src_node *, struct pf_src_node *);
static __inline int pf_state_compare_lan_ext(struct pf_state_key *,
        struct pf_state_key *);
static __inline int pf_state_compare_ext_gwy(struct pf_state_key *,
        struct pf_state_key *);
static __inline int pf_state_compare_id(struct pf_state *,
        struct pf_state *);

struct pf_src_tree tree_src_tracking;

struct pf_state_tree_id tree_id;
struct pf_state_queue state_list;

RB_GENERATE(pf_src_tree, pf_src_node, entry, pf_src_compare);
RB_GENERATE(pf_state_tree_lan_ext, pf_state_key,
    entry_lan_ext, pf_state_compare_lan_ext);
RB_GENERATE(pf_state_tree_ext_gwy, pf_state_key,
    entry_ext_gwy, pf_state_compare_ext_gwy);
RB_GENERATE(pf_state_tree_id, pf_state,
    entry_id, pf_state_compare_id);

#define PF_DT_SKIP_LANEXT       0x01
#define PF_DT_SKIP_EXTGWY       0x02

#ifdef __NetBSD__
static __inline struct pfi_kif *
bound_iface(const struct pf_rule *r, const struct pf_rule *nr,
    struct pfi_kif *k)
{
        uint32_t rule_flag;

        rule_flag = r->rule_flag;
        if (nr != NULL)
                rule_flag |= nr->rule_flag;

        return ((rule_flag & PFRULE_IFBOUND) != 0) ? k : pfi_all;
}
#endif /* __NetBSD__ */

static __inline int
pf_src_compare(struct pf_src_node *a, struct pf_src_node *b)
{
        int     diff;

        if (a->rule.ptr > b->rule.ptr)
                return (1);
        if (a->rule.ptr < b->rule.ptr)
                return (-1);
        if ((diff = a->af - b->af) != 0)
                return (diff);
        switch (a->af) {
#ifdef INET
        case AF_INET:
                if (a->addr.addr32[0] > b->addr.addr32[0])
                        return (1);
                if (a->addr.addr32[0] < b->addr.addr32[0])
                        return (-1);
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                if (a->addr.addr32[3] > b->addr.addr32[3])
                        return (1);
                if (a->addr.addr32[3] < b->addr.addr32[3])
                        return (-1);
                if (a->addr.addr32[2] > b->addr.addr32[2])
                        return (1);
                if (a->addr.addr32[2] < b->addr.addr32[2])
                        return (-1);
                if (a->addr.addr32[1] > b->addr.addr32[1])
                        return (1);
                if (a->addr.addr32[1] < b->addr.addr32[1])
                        return (-1);
                if (a->addr.addr32[0] > b->addr.addr32[0])
                        return (1);
                if (a->addr.addr32[0] < b->addr.addr32[0])
                        return (-1);
                break;
#endif /* INET6 */
        }
        return (0);
}

static __inline int
pf_state_compare_lan_ext(struct pf_state_key *a, struct pf_state_key *b)
{
        int     diff;

        if ((diff = a->proto - b->proto) != 0)
                return (diff);
        if ((diff = a->af - b->af) != 0)
                return (diff);
        switch (a->af) {
#ifdef INET
        case AF_INET:
                if (a->lan.addr.addr32[0] > b->lan.addr.addr32[0])
                        return (1);
                if (a->lan.addr.addr32[0] < b->lan.addr.addr32[0])
                        return (-1);
                if (a->ext.addr.addr32[0] > b->ext.addr.addr32[0])
                        return (1);
                if (a->ext.addr.addr32[0] < b->ext.addr.addr32[0])
                        return (-1);
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                if (a->lan.addr.addr32[3] > b->lan.addr.addr32[3])
                        return (1);
                if (a->lan.addr.addr32[3] < b->lan.addr.addr32[3])
                        return (-1);
                if (a->ext.addr.addr32[3] > b->ext.addr.addr32[3])
                        return (1);
                if (a->ext.addr.addr32[3] < b->ext.addr.addr32[3])
                        return (-1);
                if (a->lan.addr.addr32[2] > b->lan.addr.addr32[2])
                        return (1);
                if (a->lan.addr.addr32[2] < b->lan.addr.addr32[2])
                        return (-1);
                if (a->ext.addr.addr32[2] > b->ext.addr.addr32[2])
                        return (1);
                if (a->ext.addr.addr32[2] < b->ext.addr.addr32[2])
                        return (-1);
                if (a->lan.addr.addr32[1] > b->lan.addr.addr32[1])
                        return (1);
                if (a->lan.addr.addr32[1] < b->lan.addr.addr32[1])
                        return (-1);
                if (a->ext.addr.addr32[1] > b->ext.addr.addr32[1])
                        return (1);
                if (a->ext.addr.addr32[1] < b->ext.addr.addr32[1])
                        return (-1);
                if (a->lan.addr.addr32[0] > b->lan.addr.addr32[0])
                        return (1);
                if (a->lan.addr.addr32[0] < b->lan.addr.addr32[0])
                        return (-1);
                if (a->ext.addr.addr32[0] > b->ext.addr.addr32[0])
                        return (1);
                if (a->ext.addr.addr32[0] < b->ext.addr.addr32[0])
                        return (-1);
                break;
#endif /* INET6 */
        }

        if ((diff = a->lan.port - b->lan.port) != 0)
                return (diff);
        if ((diff = a->ext.port - b->ext.port) != 0)
                return (diff);

        return (0);
}

static __inline int
pf_state_compare_ext_gwy(struct pf_state_key *a, struct pf_state_key *b)
{
        int     diff;

        if ((diff = a->proto - b->proto) != 0)
                return (diff);
        if ((diff = a->af - b->af) != 0)
                return (diff);
        switch (a->af) {
#ifdef INET
        case AF_INET:
                if (a->ext.addr.addr32[0] > b->ext.addr.addr32[0])
                        return (1);
                if (a->ext.addr.addr32[0] < b->ext.addr.addr32[0])
                        return (-1);
                if (a->gwy.addr.addr32[0] > b->gwy.addr.addr32[0])
                        return (1);
                if (a->gwy.addr.addr32[0] < b->gwy.addr.addr32[0])
                        return (-1);
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                if (a->ext.addr.addr32[3] > b->ext.addr.addr32[3])
                        return (1);
                if (a->ext.addr.addr32[3] < b->ext.addr.addr32[3])
                        return (-1);
                if (a->gwy.addr.addr32[3] > b->gwy.addr.addr32[3])
                        return (1);
                if (a->gwy.addr.addr32[3] < b->gwy.addr.addr32[3])
                        return (-1);
                if (a->ext.addr.addr32[2] > b->ext.addr.addr32[2])
                        return (1);
                if (a->ext.addr.addr32[2] < b->ext.addr.addr32[2])
                        return (-1);
                if (a->gwy.addr.addr32[2] > b->gwy.addr.addr32[2])
                        return (1);
                if (a->gwy.addr.addr32[2] < b->gwy.addr.addr32[2])
                        return (-1);
                if (a->ext.addr.addr32[1] > b->ext.addr.addr32[1])
                        return (1);
                if (a->ext.addr.addr32[1] < b->ext.addr.addr32[1])
                        return (-1);
                if (a->gwy.addr.addr32[1] > b->gwy.addr.addr32[1])
                        return (1);
                if (a->gwy.addr.addr32[1] < b->gwy.addr.addr32[1])
                        return (-1);
                if (a->ext.addr.addr32[0] > b->ext.addr.addr32[0])
                        return (1);
                if (a->ext.addr.addr32[0] < b->ext.addr.addr32[0])
                        return (-1);
                if (a->gwy.addr.addr32[0] > b->gwy.addr.addr32[0])
                        return (1);
                if (a->gwy.addr.addr32[0] < b->gwy.addr.addr32[0])
                        return (-1);
                break;
#endif /* INET6 */
        }

        if ((diff = a->ext.port - b->ext.port) != 0)
                return (diff);
        if ((diff = a->gwy.port - b->gwy.port) != 0)
                return (diff);

        return (0);
}

static __inline int
pf_state_compare_id(struct pf_state *a, struct pf_state *b)
{
        if (a->id > b->id)
                return (1);
        if (a->id < b->id)
                return (-1);
        if (a->creatorid > b->creatorid)
                return (1);
        if (a->creatorid < b->creatorid)
                return (-1);

        return (0);
}

#ifdef INET6
void
pf_addrcpy(struct pf_addr *dst, const struct pf_addr *src, sa_family_t af)
{
        switch (af) {
#ifdef INET
        case AF_INET:
                dst->addr32[0] = src->addr32[0];
                break;
#endif /* INET */
        case AF_INET6:
                dst->addr32[0] = src->addr32[0];
                dst->addr32[1] = src->addr32[1];
                dst->addr32[2] = src->addr32[2];
                dst->addr32[3] = src->addr32[3];
                break;
        }
}
#endif /* INET6 */

struct pf_state *
pf_find_state_byid(struct pf_state_cmp *key)
{
        pf_status.fcounters[FCNT_STATE_SEARCH]++;
        
        return (RB_FIND(pf_state_tree_id, &tree_id, (struct pf_state *)key));
}

struct pf_state *
pf_find_state(struct pfi_kif *kif, struct pf_state_key_cmp *key, u_int8_t tree)
{
        struct pf_state_key     *sk;
        struct pf_state         *s;

        pf_status.fcounters[FCNT_STATE_SEARCH]++;

        switch (tree) {
        case PF_LAN_EXT:
                sk = RB_FIND(pf_state_tree_lan_ext, &pf_statetbl_lan_ext,
                    (struct pf_state_key *)key);
                break;
        case PF_EXT_GWY:
                sk = RB_FIND(pf_state_tree_ext_gwy, &pf_statetbl_ext_gwy,
                    (struct pf_state_key *)key);
                break;
        default:
                panic("pf_find_state");
        }

        /* list is sorted, if-bound states before floating ones */
        if (sk != NULL)
                TAILQ_FOREACH(s, &sk->states, next)
                        if (s->kif == pfi_all || s->kif == kif)
                                return (s);

        return (NULL);
}

struct pf_state *
pf_find_state_all(struct pf_state_key_cmp *key, u_int8_t tree, int *more)
{
        struct pf_state_key     *sk;
        struct pf_state         *s, *ret = NULL;

        pf_status.fcounters[FCNT_STATE_SEARCH]++;

        switch (tree) {
        case PF_LAN_EXT:
                sk = RB_FIND(pf_state_tree_lan_ext,
                    &pf_statetbl_lan_ext, (struct pf_state_key *)key);
                break;
        case PF_EXT_GWY:
                sk = RB_FIND(pf_state_tree_ext_gwy,
                    &pf_statetbl_ext_gwy, (struct pf_state_key *)key);
                break;
        default:
                panic("pf_find_state_all");
        }

        if (sk != NULL) {
                ret = TAILQ_FIRST(&sk->states);
                if (more == NULL)
                        return (ret);

                TAILQ_FOREACH(s, &sk->states, next)
                        (*more)++;
        }

        return (ret);
}

void
pf_init_threshold(struct pf_threshold *threshold,
    u_int32_t limit, u_int32_t seconds)
{
        threshold->limit = limit * PF_THRESHOLD_MULT;
        threshold->seconds = seconds;
        threshold->count = 0;
        threshold->last = time_second;
}

void
pf_add_threshold(struct pf_threshold *threshold)
{
        u_int32_t t = time_second, diff = t - threshold->last;

        if (diff >= threshold->seconds)
                threshold->count = 0;
        else
                threshold->count -= threshold->count * diff /
                    threshold->seconds;
        threshold->count += PF_THRESHOLD_MULT;
        threshold->last = t;
}

int
pf_check_threshold(struct pf_threshold *threshold)
{
        return (threshold->count > threshold->limit);
}

int
pf_src_connlimit(struct pf_state **state)
{
        int bad = 0;

        (*state)->src_node->conn++;
        (*state)->src.tcp_est = 1;
        pf_add_threshold(&(*state)->src_node->conn_rate);

        if ((*state)->rule.ptr->max_src_conn &&
            (*state)->rule.ptr->max_src_conn <
            (*state)->src_node->conn) {
                pf_status.lcounters[LCNT_SRCCONN]++;
                bad++;
        }

        if ((*state)->rule.ptr->max_src_conn_rate.limit &&
            pf_check_threshold(&(*state)->src_node->conn_rate)) {
                pf_status.lcounters[LCNT_SRCCONNRATE]++;
                bad++;
        }

        if (!bad)
                return (0);

        if ((*state)->rule.ptr->overload_tbl) {
                struct pfr_addr p;
                u_int32_t       killed = 0;

                pf_status.lcounters[LCNT_OVERLOAD_TABLE]++;
                if (pf_status.debug >= PF_DEBUG_MISC) {
                        printf("pf_src_connlimit: blocking address ");
                        pf_print_host(&(*state)->src_node->addr, 0,
                            (*state)->state_key->af);
                }

                bzero(&p, sizeof(p));
                p.pfra_af = (*state)->state_key->af;
                switch ((*state)->state_key->af) {
#ifdef INET
                case AF_INET:
                        p.pfra_net = 32;
                        p.pfra_ip4addr = (*state)->src_node->addr.v4;
                        break;
#endif /* INET */
#ifdef INET6
                case AF_INET6:
                        p.pfra_net = 128;
                        p.pfra_ip6addr = (*state)->src_node->addr.v6;
                        break;
#endif /* INET6 */
                }

                pfr_insert_kentry((*state)->rule.ptr->overload_tbl,
                    &p, time_second);

                /* kill existing states if that's required. */
                if ((*state)->rule.ptr->flush) {
                        struct pf_state_key *sk;
                        struct pf_state *st;

                        pf_status.lcounters[LCNT_OVERLOAD_FLUSH]++;
                        RB_FOREACH(st, pf_state_tree_id, &tree_id) {
                                sk = st->state_key;
                                /*
                                 * Kill states from this source.  (Only those
                                 * from the same rule if PF_FLUSH_GLOBAL is not
                                 * set)
                                 */
                                if (sk->af ==
                                    (*state)->state_key->af &&
                                    (((*state)->state_key->direction ==
                                        PF_OUT &&
                                    PF_AEQ(&(*state)->src_node->addr,
                                        &sk->lan.addr, sk->af)) ||
                                    ((*state)->state_key->direction == PF_IN &&
                                    PF_AEQ(&(*state)->src_node->addr,
                                        &sk->ext.addr, sk->af))) &&
                                    ((*state)->rule.ptr->flush &
                                    PF_FLUSH_GLOBAL ||
                                    (*state)->rule.ptr == st->rule.ptr)) {
                                        st->timeout = PFTM_PURGE;
                                        st->src.state = st->dst.state =
                                            TCPS_CLOSED;
                                        killed++;
                                }
                        }
                        if (pf_status.debug >= PF_DEBUG_MISC)
                                printf(", %u states killed", killed);
                }
                if (pf_status.debug >= PF_DEBUG_MISC)
                        printf("\n");
        }

        /* kill this state */
        (*state)->timeout = PFTM_PURGE;
        (*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
        return (1);
}

int
pf_insert_src_node(struct pf_src_node **sn, struct pf_rule *rule,
    struct pf_addr *src, sa_family_t af)
{
        struct pf_src_node      k;

        if (*sn == NULL) {
                k.af = af;
                PF_ACPY(&k.addr, src, af);
                if (rule->rule_flag & PFRULE_RULESRCTRACK ||
                    rule->rpool.opts & PF_POOL_STICKYADDR)
                        k.rule.ptr = rule;
                else
                        k.rule.ptr = NULL;
                pf_status.scounters[SCNT_SRC_NODE_SEARCH]++;
                *sn = RB_FIND(pf_src_tree, &tree_src_tracking, &k);
        }
        if (*sn == NULL) {
                if (!rule->max_src_nodes ||
                    rule->src_nodes < rule->max_src_nodes)
                        (*sn) = pool_get(&pf_src_tree_pl, PR_NOWAIT);
                else
                        pf_status.lcounters[LCNT_SRCNODES]++;
                if ((*sn) == NULL)
                        return (-1);
                bzero(*sn, sizeof(struct pf_src_node));

                pf_init_threshold(&(*sn)->conn_rate,
                    rule->max_src_conn_rate.limit,
                    rule->max_src_conn_rate.seconds);

                (*sn)->af = af;
                if (rule->rule_flag & PFRULE_RULESRCTRACK ||
                    rule->rpool.opts & PF_POOL_STICKYADDR)
                        (*sn)->rule.ptr = rule;
                else
                        (*sn)->rule.ptr = NULL;
                PF_ACPY(&(*sn)->addr, src, af);
                if (RB_INSERT(pf_src_tree,
                    &tree_src_tracking, *sn) != NULL) {
                        if (pf_status.debug >= PF_DEBUG_MISC) {
                                printf("pf: src_tree insert failed: ");
                                pf_print_host(&(*sn)->addr, 0, af);
                                printf("\n");
                        }
                        pool_put(&pf_src_tree_pl, *sn);
                        return (-1);
                }
                (*sn)->creation = time_second;
                (*sn)->ruletype = rule->action;
                if ((*sn)->rule.ptr != NULL)
                        (*sn)->rule.ptr->src_nodes++;
                pf_status.scounters[SCNT_SRC_NODE_INSERT]++;
                pf_status.src_nodes++;
        } else {
                if (rule->max_src_states &&
                    (*sn)->states >= rule->max_src_states) {
                        pf_status.lcounters[LCNT_SRCSTATES]++;
                        return (-1);
                }
        }
        return (0);
}

void
pf_stateins_err(const char *tree, struct pf_state *s, struct pfi_kif *kif)
{
        struct pf_state_key     *sk = s->state_key;

        if (pf_status.debug >= PF_DEBUG_MISC) {
                printf("pf: state insert failed: %s %s", tree, kif->pfik_name);
                printf(" lan: ");
                pf_print_host(&sk->lan.addr, sk->lan.port,
                    sk->af);
                printf(" gwy: ");
                pf_print_host(&sk->gwy.addr, sk->gwy.port,
                    sk->af);
                printf(" ext: ");
                pf_print_host(&sk->ext.addr, sk->ext.port,
                    sk->af);
                if (s->sync_flags & PFSTATE_FROMSYNC)
                        printf(" (from sync)");
                printf("\n");
        }
}

int
pf_insert_state(struct pfi_kif *kif, struct pf_state *s)
{
        struct pf_state_key     *cur;
        struct pf_state         *sp;

        KASSERT(s->state_key != NULL);
        s->kif = kif;

        if ((cur = RB_INSERT(pf_state_tree_lan_ext, &pf_statetbl_lan_ext,
            s->state_key)) != NULL) {
                /* key exists. check for same kif, if none, add to key */
                TAILQ_FOREACH(sp, &cur->states, next)
                        if (sp->kif == kif) {   /* collision! */
                                pf_stateins_err("tree_lan_ext", s, kif);
                                pf_detach_state(s,
                                    PF_DT_SKIP_LANEXT|PF_DT_SKIP_EXTGWY);
                                return (-1);
                        }
                pf_detach_state(s, PF_DT_SKIP_LANEXT|PF_DT_SKIP_EXTGWY);
                pf_attach_state(cur, s, kif == pfi_all ? 1 : 0);
        }

        /* if cur != NULL, we already found a state key and attached to it */
        if (cur == NULL && (cur = RB_INSERT(pf_state_tree_ext_gwy,
            &pf_statetbl_ext_gwy, s->state_key)) != NULL) {
                /* must not happen. we must have found the sk above! */
                pf_stateins_err("tree_ext_gwy", s, kif);
                pf_detach_state(s, PF_DT_SKIP_EXTGWY);
                return (-1);
        }

        if (s->id == 0 && s->creatorid == 0) {
                s->id = htobe64(pf_status.stateid++);
                s->creatorid = pf_status.hostid;
        }
        if (RB_INSERT(pf_state_tree_id, &tree_id, s) != NULL) {
                if (pf_status.debug >= PF_DEBUG_MISC) {
#ifdef __NetBSD__
                        printf("pf: state insert failed: "
                            "id: %016" PRIx64 " creatorid: %08x",
                            be64toh(s->id), ntohl(s->creatorid));
#else
                        printf("pf: state insert failed: "
                            "id: %016llx creatorid: %08x",
                            betoh64(s->id), ntohl(s->creatorid));
#endif /* !__NetBSD__ */
                        if (s->sync_flags & PFSTATE_FROMSYNC)
                                printf(" (from sync)");
                        printf("\n");
                }
                pf_detach_state(s, 0);
                return (-1);
        }
        TAILQ_INSERT_TAIL(&state_list, s, entry_list);
        pf_status.fcounters[FCNT_STATE_INSERT]++;
        pf_status.states++;
        pfi_kif_ref(kif, PFI_KIF_REF_STATE);
#if NPFSYNC
        pfsync_insert_state(s);
#endif
        return (0);
}

#ifdef _MODULE
volatile int pf_purge_thread_stop;
volatile int pf_purge_thread_running;
#endif

void
pf_purge_thread(void *v)
{
        int nloops = 0, s;

#ifdef _MODULE
        pf_purge_thread_running = 1;
        pf_purge_thread_stop = 0;

        while (!pf_purge_thread_stop) {
#else
        for (;;) {
#endif /* !_MODULE */
                tsleep(pf_purge_thread, PWAIT, "pftm", 1 * hz);

                s = splsoftnet();

                /* process a fraction of the state table every second */
                if (! pf_state_lock)
                        pf_purge_expired_states(1 + (pf_status.states
                                                / pf_default_rule.timeout[PFTM_INTERVAL]));

                /* purge other expired types every PFTM_INTERVAL seconds */
                if (++nloops >= pf_default_rule.timeout[PFTM_INTERVAL]) {
                        pf_purge_expired_fragments();
                        pf_purge_expired_src_nodes(0);
                        nloops = 0;
                }

                splx(s);
        }

#ifdef _MODULE
        pf_purge_thread_running = 0;
        wakeup(&pf_purge_thread_running);
        kthread_exit(0);
#endif /* _MODULE */
}

u_int32_t
pf_state_expires(const struct pf_state *state)
{
        u_int32_t       timeout;
        u_int32_t       start;
        u_int32_t       end;
        u_int32_t       states;

        /* handle all PFTM_* > PFTM_MAX here */
        if (state->timeout == PFTM_PURGE)
                return (time_second);
        if (state->timeout == PFTM_UNTIL_PACKET)
                return (0);
        KASSERT(state->timeout != PFTM_UNLINKED);
        KASSERT(state->timeout < PFTM_MAX);
        timeout = state->rule.ptr->timeout[state->timeout];
        if (!timeout)
                timeout = pf_default_rule.timeout[state->timeout];
        start = state->rule.ptr->timeout[PFTM_ADAPTIVE_START];
        if (start) {
                end = state->rule.ptr->timeout[PFTM_ADAPTIVE_END];
                states = state->rule.ptr->states;
        } else {
                start = pf_default_rule.timeout[PFTM_ADAPTIVE_START];
                end = pf_default_rule.timeout[PFTM_ADAPTIVE_END];
                states = pf_status.states;
        }
        if (end && states > start && start < end) {
                if (states < end)
                        return (state->expire + timeout * (end - states) /
                            (end - start));
                else
                        return (time_second);
        }
        return (state->expire + timeout);
}

void
pf_purge_expired_src_nodes(int waslocked)
{
         struct pf_src_node             *cur, *next;
         int                             locked = waslocked;

         for (cur = RB_MIN(pf_src_tree, &tree_src_tracking); cur; cur = next) {
                 next = RB_NEXT(pf_src_tree, &tree_src_tracking, cur);

                 if (cur->states <= 0 && cur->expire <= time_second) {
                         if (! locked) {
                                 rw_enter_write(&pf_consistency_lock);
                                 next = RB_NEXT(pf_src_tree,
                                     &tree_src_tracking, cur);
                                 locked = 1;
                         }
                         if (cur->rule.ptr != NULL) {
                                 cur->rule.ptr->src_nodes--;
                                 if (cur->rule.ptr->states <= 0 &&
                                     cur->rule.ptr->max_src_nodes <= 0)
                                         pf_rm_rule(NULL, cur->rule.ptr);
                         }
                         RB_REMOVE(pf_src_tree, &tree_src_tracking, cur);
                         pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++;
                         pf_status.src_nodes--;
                         pool_put(&pf_src_tree_pl, cur);
                 }
         }

         if (locked && !waslocked)
                rw_exit_write(&pf_consistency_lock);
}

void
pf_src_tree_remove_state(struct pf_state *s)
{
        u_int32_t timeout;

        if (s->src_node != NULL) {
                if (s->src.tcp_est)
                        --s->src_node->conn;
                if (--s->src_node->states <= 0) {
                        timeout = s->rule.ptr->timeout[PFTM_SRC_NODE];
                        if (!timeout)
                                timeout =
                                    pf_default_rule.timeout[PFTM_SRC_NODE];
                        s->src_node->expire = time_second + timeout;
                }
        }
        if (s->nat_src_node != s->src_node && s->nat_src_node != NULL) {
                if (--s->nat_src_node->states <= 0) {
                        timeout = s->rule.ptr->timeout[PFTM_SRC_NODE];
                        if (!timeout)
                                timeout =
                                    pf_default_rule.timeout[PFTM_SRC_NODE];
                        s->nat_src_node->expire = time_second + timeout;
                }
        }
        s->src_node = s->nat_src_node = NULL;
}

/* callers should be at splsoftnet */
void
pf_unlink_state(struct pf_state *cur)
{
        if (cur->src.state == PF_TCPS_PROXY_DST) {
                pf_send_tcp(cur->rule.ptr, cur->state_key->af,
                    &cur->state_key->ext.addr, &cur->state_key->lan.addr,
                    cur->state_key->ext.port, cur->state_key->lan.port,
                    cur->src.seqhi, cur->src.seqlo + 1,
                    TH_RST|TH_ACK, 0, 0, 0, 1, cur->tag, NULL, NULL);
        }
        RB_REMOVE(pf_state_tree_id, &tree_id, cur);
#if NPFSYNC
        if (cur->creatorid == pf_status.hostid)
                pfsync_delete_state(cur);
#endif
        cur->timeout = PFTM_UNLINKED;
        pf_src_tree_remove_state(cur);
        pf_detach_state(cur, 0);
}

/* callers should be at splsoftnet and hold the
 * write_lock on pf_consistency_lock */
void
pf_free_state(struct pf_state *cur)
{
#if NPFSYNC
        if (pfsyncif != NULL &&
            (pfsyncif->sc_bulk_send_next == cur ||
            pfsyncif->sc_bulk_terminator == cur))
                return;
#endif
        KASSERT(cur->timeout == PFTM_UNLINKED);
        if (--cur->rule.ptr->states <= 0 &&
            cur->rule.ptr->src_nodes <= 0)
                pf_rm_rule(NULL, cur->rule.ptr);
        if (cur->nat_rule.ptr != NULL)
                if (--cur->nat_rule.ptr->states <= 0 &&
                        cur->nat_rule.ptr->src_nodes <= 0)
                        pf_rm_rule(NULL, cur->nat_rule.ptr);
        if (cur->anchor.ptr != NULL)
                if (--cur->anchor.ptr->states <= 0)
                        pf_rm_rule(NULL, cur->anchor.ptr);
        pf_normalize_tcp_cleanup(cur);
        pfi_kif_unref(cur->kif, PFI_KIF_REF_STATE);
        TAILQ_REMOVE(&state_list, cur, entry_list);
        if (cur->tag)
                pf_tag_unref(cur->tag);
        pool_put(&pf_state_pl, cur);
        pf_status.fcounters[FCNT_STATE_REMOVALS]++;
        pf_status.states--;
}

void
pf_purge_expired_states(u_int32_t maxcheck)
{
        static struct pf_state  *cur = NULL;
        struct pf_state         *next;
        int                      locked = 0;

        while (maxcheck--) {
                /* wrap to start of list when we hit the end */
                if (cur == NULL) {
                        cur = TAILQ_FIRST(&state_list);
                        if (cur == NULL)
                                break;  /* list empty */
                }

                /* get next state, as cur may get deleted */
                next = TAILQ_NEXT(cur, entry_list);

                if (cur->timeout == PFTM_UNLINKED) {
                        /* free unlinked state */
                        if (! locked) {
                                rw_enter_write(&pf_consistency_lock);
                                locked = 1;
                        }
                        pf_free_state(cur);
                } else if (pf_state_expires(cur) <= time_second) {
                        /* unlink and free expired state */
                        pf_unlink_state(cur);
                        if (! locked) {
                                rw_enter_write(&pf_consistency_lock);
                                locked = 1;
                        }
                        pf_free_state(cur);
                }
                cur = next;
        }

        if (locked)
                rw_exit_write(&pf_consistency_lock);
}

int
pf_tbladdr_setup(struct pf_ruleset *rs, struct pf_addr_wrap *aw)
{
        if (aw->type != PF_ADDR_TABLE)
                return (0);
        if ((aw->p.tbl = pfr_attach_table(rs, aw->v.tblname)) == NULL)
                return (1);
        return (0);
}

void
pf_tbladdr_remove(struct pf_addr_wrap *aw)
{
        if (aw->type != PF_ADDR_TABLE || aw->p.tbl == NULL)
                return;
        pfr_detach_table(aw->p.tbl);
        aw->p.tbl = NULL;
}

void
pf_tbladdr_copyout(struct pf_addr_wrap *aw)
{
        struct pfr_ktable *kt = aw->p.tbl;

        if (aw->type != PF_ADDR_TABLE || kt == NULL)
                return;
        if (!(kt->pfrkt_flags & PFR_TFLAG_ACTIVE) && kt->pfrkt_root != NULL)
                kt = kt->pfrkt_root;
        aw->p.tbl = NULL;
        aw->p.tblcnt = (kt->pfrkt_flags & PFR_TFLAG_ACTIVE) ?
                kt->pfrkt_cnt : -1;
}

void
pf_print_host(struct pf_addr *addr, u_int16_t p, sa_family_t af)
{
        switch (af) {
#ifdef INET
        case AF_INET: {
                u_int32_t a = ntohl(addr->addr32[0]);
                printf("%u.%u.%u.%u", (a>>24)&255, (a>>16)&255,
                    (a>>8)&255, a&255);
                if (p) {
                        p = ntohs(p);
                        printf(":%u", p);
                }
                break;
        }
#endif /* INET */
#ifdef INET6
        case AF_INET6: {
                u_int16_t b;
                u_int8_t i, curstart = 255, curend = 0,
                    maxstart = 0, maxend = 0;
                for (i = 0; i < 8; i++) {
                        if (!addr->addr16[i]) {
                                if (curstart == 255)
                                        curstart = i;
                                else
                                        curend = i;
                        } else {
                                if (curstart) {
                                        if ((curend - curstart) >
                                            (maxend - maxstart)) {
                                                maxstart = curstart;
                                                maxend = curend;
                                                curstart = 255;
                                        }
                                }
                        }
                }
                for (i = 0; i < 8; i++) {
                        if (i >= maxstart && i <= maxend) {
                                if (maxend != 7) {
                                        if (i == maxstart)
                                                printf(":");
                                } else {
                                        if (i == maxend)
                                                printf(":");
                                }
                        } else {
                                b = ntohs(addr->addr16[i]);
                                printf("%x", b);
                                if (i < 7)
                                        printf(":");
                        }
                }
                if (p) {
                        p = ntohs(p);
                        printf("[%u]", p);
                }
                break;
        }
#endif /* INET6 */
        }
}

void
pf_print_state(struct pf_state *s)
{
        struct pf_state_key *sk = s->state_key;
        switch (sk->proto) {
        case IPPROTO_TCP:
                printf("TCP ");
                break;
        case IPPROTO_UDP:
                printf("UDP ");
                break;
        case IPPROTO_ICMP:
                printf("ICMP ");
                break;
        case IPPROTO_ICMPV6:
                printf("ICMPV6 ");
                break;
        default:
                printf("%u ", sk->proto);
                break;
        }
        pf_print_host(&sk->lan.addr, sk->lan.port, sk->af);
        printf(" ");
        pf_print_host(&sk->gwy.addr, sk->gwy.port, sk->af);
        printf(" ");
        pf_print_host(&sk->ext.addr, sk->ext.port, sk->af);
        printf(" [lo=%u high=%u win=%u modulator=%u", s->src.seqlo,
            s->src.seqhi, s->src.max_win, s->src.seqdiff);
        if (s->src.wscale && s->dst.wscale)
                printf(" wscale=%u", s->src.wscale & PF_WSCALE_MASK);
        printf("]");
        printf(" [lo=%u high=%u win=%u modulator=%u", s->dst.seqlo,
            s->dst.seqhi, s->dst.max_win, s->dst.seqdiff);
        if (s->src.wscale && s->dst.wscale)
                printf(" wscale=%u", s->dst.wscale & PF_WSCALE_MASK);
        printf("]");
        printf(" %u:%u", s->src.state, s->dst.state);
}

void
pf_print_flags(u_int8_t f)
{
        if (f)
                printf(" ");
        if (f & TH_FIN)
                printf("F");
        if (f & TH_SYN)
                printf("S");
        if (f & TH_RST)
                printf("R");
        if (f & TH_PUSH)
                printf("P");
        if (f & TH_ACK)
                printf("A");
        if (f & TH_URG)
                printf("U");
        if (f & TH_ECE)
                printf("E");
        if (f & TH_CWR)
                printf("W");
}

#define PF_SET_SKIP_STEPS(i)                                    \
        do {                                                    \
                while (head[i] != cur) {                        \
                        head[i]->skip[i].ptr = cur;             \
                        head[i] = TAILQ_NEXT(head[i], entries); \
                }                                               \
        } while (0)

void
pf_calc_skip_steps(struct pf_rulequeue *rules)
{
        struct pf_rule *cur, *prev, *head[PF_SKIP_COUNT];
        int i;

        cur = TAILQ_FIRST(rules);
        prev = cur;
        for (i = 0; i < PF_SKIP_COUNT; ++i)
                head[i] = cur;
        while (cur != NULL) {

                if (cur->kif != prev->kif || cur->ifnot != prev->ifnot)
                        PF_SET_SKIP_STEPS(PF_SKIP_IFP);
                if (cur->direction != prev->direction)
                        PF_SET_SKIP_STEPS(PF_SKIP_DIR);
                if (cur->af != prev->af)
                        PF_SET_SKIP_STEPS(PF_SKIP_AF);
                if (cur->proto != prev->proto)
                        PF_SET_SKIP_STEPS(PF_SKIP_PROTO);
                if (cur->src.neg != prev->src.neg ||
                    pf_addr_wrap_neq(&cur->src.addr, &prev->src.addr))
                        PF_SET_SKIP_STEPS(PF_SKIP_SRC_ADDR);
                if (cur->src.port[0] != prev->src.port[0] ||
                    cur->src.port[1] != prev->src.port[1] ||
                    cur->src.port_op != prev->src.port_op)
                        PF_SET_SKIP_STEPS(PF_SKIP_SRC_PORT);
                if (cur->dst.neg != prev->dst.neg ||
                    pf_addr_wrap_neq(&cur->dst.addr, &prev->dst.addr))
                        PF_SET_SKIP_STEPS(PF_SKIP_DST_ADDR);
                if (cur->dst.port[0] != prev->dst.port[0] ||
                    cur->dst.port[1] != prev->dst.port[1] ||
                    cur->dst.port_op != prev->dst.port_op)
                        PF_SET_SKIP_STEPS(PF_SKIP_DST_PORT);

                prev = cur;
                cur = TAILQ_NEXT(cur, entries);
        }
        for (i = 0; i < PF_SKIP_COUNT; ++i)
                PF_SET_SKIP_STEPS(i);
}

int
pf_addr_wrap_neq(struct pf_addr_wrap *aw1, struct pf_addr_wrap *aw2)
{
        if (aw1->type != aw2->type)
                return (1);
        switch (aw1->type) {
        case PF_ADDR_ADDRMASK:
                if (PF_ANEQ(&aw1->v.a.addr, &aw2->v.a.addr, 0))
                        return (1);
                if (PF_ANEQ(&aw1->v.a.mask, &aw2->v.a.mask, 0))
                        return (1);
                return (0);
        case PF_ADDR_DYNIFTL:
                return (aw1->p.dyn->pfid_kt != aw2->p.dyn->pfid_kt);
        case PF_ADDR_NOROUTE:
        case PF_ADDR_URPFFAILED:
                return (0);
        case PF_ADDR_TABLE:
                return (aw1->p.tbl != aw2->p.tbl);
        case PF_ADDR_RTLABEL:
                return (aw1->v.rtlabel != aw2->v.rtlabel);
        default:
                printf("invalid address type: %d\n", aw1->type);
                return (1);
        }
}

u_int16_t
pf_cksum_fixup(u_int16_t cksum, u_int16_t old, u_int16_t new, u_int8_t udp)
{
        u_int32_t       l;

        if (udp && !cksum)
                return (0x0000);
        l = cksum + old - new;
        l = (l >> 16) + (l & 65535);
        l = l & 65535;
        if (udp && !l)
                return (0xFFFF);
        return (l);
}

void
pf_change_ap(struct pf_addr *a, u_int16_t *p, u_int16_t *ic, u_int16_t *pc,
    struct pf_addr *an, u_int16_t pn, u_int8_t u, sa_family_t af)
{
        struct pf_addr  ao;
        u_int16_t       po = *p;

        PF_ACPY(&ao, a, af);
        PF_ACPY(a, an, af);

        *p = pn;

        switch (af) {
#ifdef INET
        case AF_INET:
                *ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
                    ao.addr16[0], an->addr16[0], 0),
                    ao.addr16[1], an->addr16[1], 0);
                *p = pn;
                *pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(*pc,
                    ao.addr16[0], an->addr16[0], u),
                    ao.addr16[1], an->addr16[1], u),
                    po, pn, u);
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                *pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
                    pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
                    pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(*pc,
                    ao.addr16[0], an->addr16[0], u),
                    ao.addr16[1], an->addr16[1], u),
                    ao.addr16[2], an->addr16[2], u),
                    ao.addr16[3], an->addr16[3], u),
                    ao.addr16[4], an->addr16[4], u),
                    ao.addr16[5], an->addr16[5], u),
                    ao.addr16[6], an->addr16[6], u),
                    ao.addr16[7], an->addr16[7], u),
                    po, pn, u);
                break;
#endif /* INET6 */
        }
}


/* Changes a u_int32_t.  Uses a void * so there are no align restrictions */
void
pf_change_a(void *a, u_int16_t *c, u_int32_t an, u_int8_t u)
{
        u_int32_t       ao;

        memcpy(&ao, a, sizeof(ao));
        memcpy(a, &an, sizeof(u_int32_t));
        *c = pf_cksum_fixup(pf_cksum_fixup(*c, ao / 65536, an / 65536, u),
            ao % 65536, an % 65536, u);
}

#ifdef INET6
void
pf_change_a6(struct pf_addr *a, u_int16_t *c, struct pf_addr *an, u_int8_t u)
{
        struct pf_addr  ao;

        PF_ACPY(&ao, a, AF_INET6);
        PF_ACPY(a, an, AF_INET6);

        *c = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
            pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
            pf_cksum_fixup(pf_cksum_fixup(*c,
            ao.addr16[0], an->addr16[0], u),
            ao.addr16[1], an->addr16[1], u),
            ao.addr16[2], an->addr16[2], u),
            ao.addr16[3], an->addr16[3], u),
            ao.addr16[4], an->addr16[4], u),
            ao.addr16[5], an->addr16[5], u),
            ao.addr16[6], an->addr16[6], u),
            ao.addr16[7], an->addr16[7], u);
}
#endif /* INET6 */

void
pf_change_icmp(struct pf_addr *ia, u_int16_t *ip, struct pf_addr *oa,
    struct pf_addr *na, u_int16_t np, u_int16_t *pc, u_int16_t *h2c,
    u_int16_t *ic, u_int16_t *hc, u_int8_t u, sa_family_t af)
{
        struct pf_addr  oia, ooa;

        PF_ACPY(&oia, ia, af);
        PF_ACPY(&ooa, oa, af);

        /* Change inner protocol port, fix inner protocol checksum. */
        if (ip != NULL) {
                u_int16_t       oip = *ip;
                u_int32_t       opc = 0;

                if (pc != NULL)
                        opc = *pc;
                *ip = np;
                if (pc != NULL)
                        *pc = pf_cksum_fixup(*pc, oip, *ip, u);
                *ic = pf_cksum_fixup(*ic, oip, *ip, 0);
                if (pc != NULL)
                        *ic = pf_cksum_fixup(*ic, opc, *pc, 0);
        }
        /* Change inner ip address, fix inner ip and icmp checksums. */
        PF_ACPY(ia, na, af);
        switch (af) {
#ifdef INET
        case AF_INET: {
                u_int32_t        oh2c = *h2c;

                *h2c = pf_cksum_fixup(pf_cksum_fixup(*h2c,
                    oia.addr16[0], ia->addr16[0], 0),
                    oia.addr16[1], ia->addr16[1], 0);
                *ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
                    oia.addr16[0], ia->addr16[0], 0),
                    oia.addr16[1], ia->addr16[1], 0);
                *ic = pf_cksum_fixup(*ic, oh2c, *h2c, 0);
                break;
        }
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
                    pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
                    pf_cksum_fixup(pf_cksum_fixup(*ic,
                    oia.addr16[0], ia->addr16[0], u),
                    oia.addr16[1], ia->addr16[1], u),
                    oia.addr16[2], ia->addr16[2], u),
                    oia.addr16[3], ia->addr16[3], u),
                    oia.addr16[4], ia->addr16[4], u),
                    oia.addr16[5], ia->addr16[5], u),
                    oia.addr16[6], ia->addr16[6], u),
                    oia.addr16[7], ia->addr16[7], u);
                break;
#endif /* INET6 */
        }
        /* Change outer ip address, fix outer ip or icmpv6 checksum. */
        PF_ACPY(oa, na, af);
        switch (af) {
#ifdef INET
        case AF_INET:
                *hc = pf_cksum_fixup(pf_cksum_fixup(*hc,
                    ooa.addr16[0], oa->addr16[0], 0),
                    ooa.addr16[1], oa->addr16[1], 0);
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
                    pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
                    pf_cksum_fixup(pf_cksum_fixup(*ic,
                    ooa.addr16[0], oa->addr16[0], u),
                    ooa.addr16[1], oa->addr16[1], u),
                    ooa.addr16[2], oa->addr16[2], u),
                    ooa.addr16[3], oa->addr16[3], u),
                    ooa.addr16[4], oa->addr16[4], u),
                    ooa.addr16[5], oa->addr16[5], u),
                    ooa.addr16[6], oa->addr16[6], u),
                    ooa.addr16[7], oa->addr16[7], u);
                break;
#endif /* INET6 */
        }
}


/*
 * Need to modulate the sequence numbers in the TCP SACK option
 * (credits to Krzysztof Pfaff for report and patch)
 */
int
pf_modulate_sack(struct mbuf *m, int off, struct pf_pdesc *pd,
    struct tcphdr *th, struct pf_state_peer *dst)
{
        int hlen = (th->th_off << 2) - sizeof(*th), thoptlen = hlen;
        u_int8_t opts[MAX_TCPOPTLEN], *opt = opts;
        int copyback = 0, i, olen;
        struct sackblk sack;

#ifdef __NetBSD__
#define TCPOLEN_SACK            8               /* 2*sizeof(tcp_seq) */
#endif

#define TCPOLEN_SACKLEN (TCPOLEN_SACK + 2)
        if (hlen < TCPOLEN_SACKLEN ||
            !pf_pull_hdr(m, off + sizeof(*th), opts, hlen, NULL, NULL, pd->af))
                return 0;

        while (hlen >= TCPOLEN_SACKLEN) {
                olen = opt[1];
                switch (*opt) {
                case TCPOPT_EOL:        /* FALLTHROUGH */
                case TCPOPT_NOP:
                        opt++;
                        hlen--;
                        break;
                case TCPOPT_SACK:
                        if (olen > hlen)
                                olen = hlen;
                        if (olen >= TCPOLEN_SACKLEN) {
                                for (i = 2; i + TCPOLEN_SACK <= olen;
                                    i += TCPOLEN_SACK) {
                                        memcpy(&sack, &opt[i], sizeof(sack));
#ifdef __NetBSD__
#define SACK_START      sack.left
#define SACK_END        sack.right
#else
#define SACK_START      sack.start
#define SACK_END        sack.end
#endif
                                        pf_change_a(&SACK_START, &th->th_sum,
                                            htonl(ntohl(SACK_START) -
                                            dst->seqdiff), 0);
                                        pf_change_a(&SACK_END, &th->th_sum,
                                            htonl(ntohl(SACK_END) -
                                            dst->seqdiff), 0);
#undef SACK_START
#undef SACK_END
                                        memcpy(&opt[i], &sack, sizeof(sack));
                                }
                                copyback = 1;
                        }
                        /* FALLTHROUGH */
                default:
                        if (olen < 2)
                                olen = 2;
                        hlen -= olen;
                        opt += olen;
                }
        }

        if (copyback)
                m_copyback(m, off + sizeof(*th), thoptlen, opts);
        return (copyback);
}

void
pf_send_tcp(const struct pf_rule *r, sa_family_t af,
    const struct pf_addr *saddr, const struct pf_addr *daddr,
    u_int16_t sport, u_int16_t dport, u_int32_t seq, u_int32_t ack,
    u_int8_t flags, u_int16_t win, u_int16_t mss, u_int8_t ttl, int tag,
    u_int16_t rtag, struct ether_header *eh, struct ifnet *ifp)
{
        struct mbuf     *m;
        int              len, tlen;
#ifdef INET
        struct ip       *h = NULL;
#endif /* INET */
#ifdef INET6
        struct ip6_hdr  *h6 = NULL;
#endif /* INET6 */
        struct tcphdr   *th;
        char            *opt;
#ifdef __NetBSD__
        struct pf_mtag  *pf_mtag;
#endif /* __NetBSD__ */

        /* maximum segment size tcp option */
        tlen = sizeof(struct tcphdr);
        if (mss)
                tlen += 4;

        switch (af) {
#ifdef INET
        case AF_INET:
                len = sizeof(struct ip) + tlen;
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                len = sizeof(struct ip6_hdr) + tlen;
                break;
#endif /* INET6 */
        default:
                return;
        }

        /* create outgoing mbuf */
        m = m_gethdr(M_DONTWAIT, MT_HEADER);
        if (m == NULL)
                return;
#ifdef __NetBSD__
        if ((pf_mtag = pf_get_mtag(m)) == NULL) {
                m_freem(m);
                return;
        }
        if (tag)
                pf_mtag->flags |= PF_TAG_GENERATED;
        pf_mtag->tag = rtag;

        if (r != NULL && r->rtableid >= 0)
                pf_mtag->rtableid = r->rtableid;
#else
        if (tag)
                m->m_pkthdr.pf.flags |= PF_TAG_GENERATED;
        m->m_pkthdr.pf.tag = rtag;

        if (r != NULL && r->rtableid >= 0)
                m->m_pkthdr.pf.rtableid = r->rtableid;
#endif /* !__NetBSD__ */

#ifdef ALTQ
        if (r != NULL && r->qid) {
#ifdef __NetBSD__
                struct m_tag    *mtag;
                struct altq_tag *atag;

                mtag = m_tag_get(PACKET_TAG_ALTQ_QID, sizeof(*atag), M_NOWAIT);
                if (mtag != NULL) {
                        atag = (struct altq_tag *)(mtag + 1);
                        atag->qid = r->qid;
                        /* add hints for ecn */
                        atag->af = af;
                        atag->hdr = mtod(m, struct ip *);
                        m_tag_prepend(m, mtag);
                }
#else
                m->m_pkthdr.pf.qid = r->qid;
                /* add hints for ecn */
                m->m_pkthdr.pf.hdr = mtod(m, struct ip *);
#endif /* !__NetBSD__ */
        }
#endif /* ALTQ */
        m->m_data += max_linkhdr;
        m->m_pkthdr.len = m->m_len = len;
        m_reset_rcvif(m);
        bzero(m->m_data, len);
        switch (af) {
#ifdef INET
        case AF_INET:
                h = mtod(m, struct ip *);

                /* IP header fields included in the TCP checksum */
                h->ip_p = IPPROTO_TCP;
                h->ip_len = htons(tlen);
                h->ip_src.s_addr = saddr->v4.s_addr;
                h->ip_dst.s_addr = daddr->v4.s_addr;

                th = (struct tcphdr *)((char *)h + sizeof(struct ip));
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                h6 = mtod(m, struct ip6_hdr *);

                /* IP header fields included in the TCP checksum */
                h6->ip6_nxt = IPPROTO_TCP;
                h6->ip6_plen = htons(tlen);
                memcpy(&h6->ip6_src, &saddr->v6, sizeof(struct in6_addr));
                memcpy(&h6->ip6_dst, &daddr->v6, sizeof(struct in6_addr));

                th = (struct tcphdr *)((char *)h6 + sizeof(struct ip6_hdr));
                break;
#endif /* INET6 */
        default:
                m_freem(m);
                return;
        }

        /* TCP header */
        th->th_sport = sport;
        th->th_dport = dport;
        th->th_seq = htonl(seq);
        th->th_ack = htonl(ack);
        th->th_off = tlen >> 2;
        th->th_flags = flags;
        th->th_win = htons(win);

        if (mss) {
                opt = (char *)(th + 1);
                opt[0] = TCPOPT_MAXSEG;
                opt[1] = 4;
                HTONS(mss);
                bcopy((void *)&mss, (void *)(opt + 2), 2);
        }

        switch (af) {
#ifdef INET
        case AF_INET:
                /* TCP checksum */
                th->th_sum = in_cksum(m, len);

                /* Finish the IP header */
                h->ip_v = 4;
                h->ip_hl = sizeof(*h) >> 2;
                h->ip_tos = IPTOS_LOWDELAY;
                h->ip_len = htons(len);
                h->ip_off = htons(ip_mtudisc ? IP_DF : 0);
                h->ip_ttl = ttl ? ttl : ip_defttl;
                h->ip_sum = 0;
                if (eh == NULL) {
                        ip_output(m, (void *)NULL, (void *)NULL, 0,
                            (void *)NULL, (void *)NULL);
                } else {
#ifdef __NetBSD__
                        /*
                         * On netbsd, pf_test and pf_test6 are always called
                         * with eh == NULL.
                         */
                        panic("pf_send_tcp: eh != NULL");
#else
                        struct route             ro;
                        struct rtentry           rt;
                        struct ether_header     *e = (void *)ro.ro_dst.sa_data;

                        if (ifp == NULL) {
                                m_freem(m);
                                return;
                        }
                        rt.rt_ifp = ifp;
                        ro.ro_rt = &rt;
                        ro.ro_dst.sa_len = sizeof(ro.ro_dst);
                        ro.ro_dst.sa_family = pseudo_AF_HDRCMPLT;
                        bcopy(eh->ether_dhost, e->ether_shost, ETHER_ADDR_LEN);
                        bcopy(eh->ether_shost, e->ether_dhost, ETHER_ADDR_LEN);
                        e->ether_type = eh->ether_type;
                        ip_output(m, (void *)NULL, &ro, IP_ROUTETOETHER,
                            (void *)NULL, (void *)NULL);
#endif /* !__NetBSD__ */
                }
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                /* TCP checksum */
                th->th_sum = in6_cksum(m, IPPROTO_TCP,
                    sizeof(struct ip6_hdr), tlen);

                h6->ip6_vfc |= IPV6_VERSION;
                h6->ip6_hlim = IPV6_DEFHLIM;

                ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL);
                break;
#endif /* INET6 */
        }
}

void
pf_send_icmp(struct mbuf *m, u_int8_t type, u_int8_t code, sa_family_t af,
    struct pf_rule *r)
{
        struct mbuf     *m0;
#ifdef __NetBSD__
        struct pf_mtag  *pf_mtag;
#endif /* __NetBSD__ */

#ifdef __NetBSD__
        m0 = m_copym(m, 0, M_COPYALL, M_DONTWAIT);
#else
        m0 = m_copy(m, 0, M_COPYALL);
#endif

#ifdef __NetBSD__
        if ((pf_mtag = pf_get_mtag(m0)) == NULL)
                return;
        pf_mtag->flags |= PF_TAG_GENERATED;

        if (r->rtableid >= 0)
                pf_mtag->rtableid = r->rtableid;
#else
        m0->m_pkthdr.pf.flags |= PF_TAG_GENERATED;

        if (r->rtableid >= 0)
                m0->m_pkthdr.pf.rtableid = r->rtableid;
#endif /* !__NetBSD__ */

#ifdef ALTQ
        if (r->qid) {
#ifdef __NetBSD__
                struct m_tag    *mtag;
                struct altq_tag *atag;

                mtag = m_tag_get(PACKET_TAG_ALTQ_QID, sizeof(*atag), M_NOWAIT);
                if (mtag != NULL) {
                        atag = (struct altq_tag *)(mtag + 1);
                        atag->qid = r->qid;
                        /* add hints for ecn */
                        atag->af = af;
                        atag->hdr = mtod(m0, struct ip *);
                        m_tag_prepend(m0, mtag);
                }
#else
                m0->m_pkthdr.pf.qid = r->qid;
                /* add hints for ecn */
                m0->m_pkthdr.pf.hdr = mtod(m0, struct ip *);
#endif /* !__NetBSD__ */
        }
#endif /* ALTQ */

        switch (af) {
#ifdef INET
        case AF_INET:
                icmp_error(m0, type, code, 0, 0);
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                icmp6_error(m0, type, code, 0);
                break;
#endif /* INET6 */
        }
}

/*
 * Return 1 if the addresses a and b match (with mask m), otherwise return 0.
 * If n is 0, they match if they are equal. If n is != 0, they match if they
 * are different.
 */
int
pf_match_addr(u_int8_t n, struct pf_addr *a, struct pf_addr *m,
    struct pf_addr *b, sa_family_t af)
{
        int     match = 0;

        switch (af) {
#ifdef INET
        case AF_INET:
                if ((a->addr32[0] & m->addr32[0]) ==
                    (b->addr32[0] & m->addr32[0]))
                        match++;
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                if (((a->addr32[0] & m->addr32[0]) ==
                     (b->addr32[0] & m->addr32[0])) &&
                    ((a->addr32[1] & m->addr32[1]) ==
                     (b->addr32[1] & m->addr32[1])) &&
                    ((a->addr32[2] & m->addr32[2]) ==
                     (b->addr32[2] & m->addr32[2])) &&
                    ((a->addr32[3] & m->addr32[3]) ==
                     (b->addr32[3] & m->addr32[3])))
                        match++;
                break;
#endif /* INET6 */
        }
        if (match) {
                if (n)
                        return (0);
                else
                        return (1);
        } else {
                if (n)
                        return (1);
                else
                        return (0);
        }
}

int
pf_match(u_int8_t op, u_int32_t a1, u_int32_t a2, u_int32_t p)
{
        switch (op) {
        case PF_OP_IRG:
                return ((p > a1) && (p < a2));
        case PF_OP_XRG:
                return ((p < a1) || (p > a2));
        case PF_OP_RRG:
                return ((p >= a1) && (p <= a2));
        case PF_OP_EQ:
                return (p == a1);
        case PF_OP_NE:
                return (p != a1);
        case PF_OP_LT:
                return (p < a1);
        case PF_OP_LE:
                return (p <= a1);
        case PF_OP_GT:
                return (p > a1);
        case PF_OP_GE:
                return (p >= a1);
        }
        return (0); /* never reached */
}

int
pf_match_port(u_int8_t op, u_int16_t a1, u_int16_t a2, u_int16_t p)
{
        NTOHS(a1);
        NTOHS(a2);
        NTOHS(p);
        return (pf_match(op, a1, a2, p));
}

int
pf_match_uid(u_int8_t op, uid_t a1, uid_t a2, uid_t u)
{
        if (u == UID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
                return (0);
        return (pf_match(op, a1, a2, u));
}

int
pf_match_gid(u_int8_t op, gid_t a1, gid_t a2, gid_t g)
{
        if (g == GID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
                return (0);
        return (pf_match(op, a1, a2, g));
}

int
pf_match_tag(struct mbuf *m, struct pf_rule *r, int *tag)
{
#ifdef __NetBSD__
        if (*tag == -1) {
                struct pf_mtag *pf_mtag = pf_get_mtag(m);
                if (pf_mtag == NULL)
                        return (0);

                *tag = pf_mtag->tag;
        }
#else
        if (*tag == -1)
                *tag = m->m_pkthdr.pf.tag;
#endif /* !__NetBSD__ */

        return ((!r->match_tag_not && r->match_tag == *tag) ||
            (r->match_tag_not && r->match_tag != *tag));
}

int
pf_tag_packet(struct mbuf *m, int tag, int rtableid)
{
        if (tag <= 0 && rtableid < 0)
                return (0);

#ifdef __NetBSD__
        if (tag > 0 || rtableid > 0) {
                struct pf_mtag *pf_mtag = pf_get_mtag(m);
                if (pf_mtag == NULL)
                        return (1);

                if (tag > 0)
                        pf_mtag->tag = tag;
                if (rtableid > 0)
                        pf_mtag->rtableid = rtableid;
        }
#else
        if (tag > 0)
                m->m_pkthdr.pf.tag = tag;
        if (rtableid >= 0)
                m->m_pkthdr.pf.rtableid = rtableid;
#endif /* !__NetBSD__ */

        return (0);
}

void
pf_step_into_anchor(int *depth, struct pf_ruleset **rs, int n,
    struct pf_rule **r, struct pf_rule **a,  int *match)
{
        struct pf_anchor_stackframe     *f;

        (*r)->anchor->match = 0;
        if (match)
                *match = 0;
        if (*depth >= sizeof(pf_anchor_stack) /
            sizeof(pf_anchor_stack[0])) {
                printf("pf_step_into_anchor: stack overflow\n");
                *r = TAILQ_NEXT(*r, entries);
                return;
        } else if (*depth == 0 && a != NULL)
                *a = *r;
        f = pf_anchor_stack + (*depth)++;
        f->rs = *rs;
        f->r = *r;
        if ((*r)->anchor_wildcard) {
                f->parent = &(*r)->anchor->children;
                if ((f->child = RB_MIN(pf_anchor_node, f->parent)) ==
                    NULL) {
                        *r = NULL;
                        return;
                }
                *rs = &f->child->ruleset;
        } else {
                f->parent = NULL;
                f->child = NULL;
                *rs = &(*r)->anchor->ruleset;
        }
        *r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
}

int
pf_step_out_of_anchor(int *depth, struct pf_ruleset **rs, int n,
    struct pf_rule **r, struct pf_rule **a, int *match)
{
        struct pf_anchor_stackframe     *f;
        int quick = 0;

        do {
                if (*depth <= 0)
                        break;
                f = pf_anchor_stack + *depth - 1;
                if (f->parent != NULL && f->child != NULL) {
                        if (f->child->match ||
                            (match != NULL && *match)) {
                                f->r->anchor->match = 1;
                                *match = 0;
                        }
                        f->child = RB_NEXT(pf_anchor_node, f->parent, f->child);
                        if (f->child != NULL) {
                                *rs = &f->child->ruleset;
                                *r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
                                if (*r == NULL)
                                        continue;
                                else
                                        break;
                        }
                }
                (*depth)--;
                if (*depth == 0 && a != NULL)
                        *a = NULL;
                *rs = f->rs;
                if (f->r->anchor->match || (match  != NULL && *match))
                        quick = f->r->quick;
                *r = TAILQ_NEXT(f->r, entries);
        } while (*r == NULL);

        return (quick);
}

#ifdef INET6
void
pf_poolmask(struct pf_addr *naddr, struct pf_addr *raddr,
    struct pf_addr *rmask, const struct pf_addr *saddr, sa_family_t af)
{
        switch (af) {
#ifdef INET
        case AF_INET:
                naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
                ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
                break;
#endif /* INET */
        case AF_INET6:
                naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
                ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
                naddr->addr32[1] = (raddr->addr32[1] & rmask->addr32[1]) |
                ((rmask->addr32[1] ^ 0xffffffff ) & saddr->addr32[1]);
                naddr->addr32[2] = (raddr->addr32[2] & rmask->addr32[2]) |
                ((rmask->addr32[2] ^ 0xffffffff ) & saddr->addr32[2]);
                naddr->addr32[3] = (raddr->addr32[3] & rmask->addr32[3]) |
                ((rmask->addr32[3] ^ 0xffffffff ) & saddr->addr32[3]);
                break;
        }
}

void
pf_addr_inc(struct pf_addr *addr, sa_family_t af)
{
        switch (af) {
#ifdef INET
        case AF_INET:
                addr->addr32[0] = htonl(ntohl(addr->addr32[0]) + 1);
                break;
#endif /* INET */
        case AF_INET6:
                if (addr->addr32[3] == 0xffffffff) {
                        addr->addr32[3] = 0;
                        if (addr->addr32[2] == 0xffffffff) {
                                addr->addr32[2] = 0;
                                if (addr->addr32[1] == 0xffffffff) {
                                        addr->addr32[1] = 0;
                                        addr->addr32[0] =
                                            htonl(ntohl(addr->addr32[0]) + 1);
                                } else
                                        addr->addr32[1] =
                                            htonl(ntohl(addr->addr32[1]) + 1);
                        } else
                                addr->addr32[2] =
                                    htonl(ntohl(addr->addr32[2]) + 1);
                } else
                        addr->addr32[3] =
                            htonl(ntohl(addr->addr32[3]) + 1);
                break;
        }
}
#endif /* INET6 */

#define mix(a,b,c) \
        do {                                    \
                a -= b; a -= c; a ^= (c >> 13); \
                b -= c; b -= a; b ^= (a << 8);  \
                c -= a; c -= b; c ^= (b >> 13); \
                a -= b; a -= c; a ^= (c >> 12); \
                b -= c; b -= a; b ^= (a << 16); \
                c -= a; c -= b; c ^= (b >> 5);  \
                a -= b; a -= c; a ^= (c >> 3);  \
                b -= c; b -= a; b ^= (a << 10); \
                c -= a; c -= b; c ^= (b >> 15); \
        } while (0)

/*
 * hash function based on bridge_hash in if_bridge.c
 */
void
pf_hash(const struct pf_addr *inaddr, struct pf_addr *hash,
    struct pf_poolhashkey *key, sa_family_t af)
{
        u_int32_t       a = 0x9e3779b9, b = 0x9e3779b9, c = key->key32[0];

        switch (af) {
#ifdef INET
        case AF_INET:
                a += inaddr->addr32[0];
                b += key->key32[1];
                mix(a, b, c);
                hash->addr32[0] = c + key->key32[2];
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                a += inaddr->addr32[0];
                b += inaddr->addr32[2];
                mix(a, b, c);
                hash->addr32[0] = c;
                a += inaddr->addr32[1];
                b += inaddr->addr32[3];
                c += key->key32[1];
                mix(a, b, c);
                hash->addr32[1] = c;
                a += inaddr->addr32[2];
                b += inaddr->addr32[1];
                c += key->key32[2];
                mix(a, b, c);
                hash->addr32[2] = c;
                a += inaddr->addr32[3];
                b += inaddr->addr32[0];
                c += key->key32[3];
                mix(a, b, c);
                hash->addr32[3] = c;
                break;
#endif /* INET6 */
        }
}

int
pf_map_addr(sa_family_t af, struct pf_rule *r, const struct pf_addr *saddr,
    struct pf_addr *naddr, struct pf_addr *init_addr, struct pf_src_node **sn)
{
        unsigned char            hash[16];
        struct pf_pool          *rpool = &r->rpool;
        struct pf_addr          *raddr = &rpool->cur->addr.v.a.addr;
        struct pf_addr          *rmask = &rpool->cur->addr.v.a.mask;
        struct pf_pooladdr      *acur = rpool->cur;
        struct pf_src_node       k;

        if (*sn == NULL && r->rpool.opts & PF_POOL_STICKYADDR &&
            (r->rpool.opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) {
                k.af = af;
                PF_ACPY(&k.addr, saddr, af);
                if (r->rule_flag & PFRULE_RULESRCTRACK ||
                    r->rpool.opts & PF_POOL_STICKYADDR)
                        k.rule.ptr = r;
                else
                        k.rule.ptr = NULL;
                pf_status.scounters[SCNT_SRC_NODE_SEARCH]++;
                *sn = RB_FIND(pf_src_tree, &tree_src_tracking, &k);
                if (*sn != NULL && !PF_AZERO(&(*sn)->raddr, af)) {
                        PF_ACPY(naddr, &(*sn)->raddr, af);
                        if (pf_status.debug >= PF_DEBUG_MISC) {
                                printf("pf_map_addr: src tracking maps ");
                                pf_print_host(&k.addr, 0, af);
                                printf(" to ");
                                pf_print_host(naddr, 0, af);
                                printf("\n");
                        }
                        return (0);
                }
        }

        if (rpool->cur->addr.type == PF_ADDR_NOROUTE)
                return (1);
        if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
                switch (af) {
#ifdef INET
                case AF_INET:
                        if (rpool->cur->addr.p.dyn->pfid_acnt4 < 1 &&
                            (rpool->opts & PF_POOL_TYPEMASK) !=
                            PF_POOL_ROUNDROBIN)
                                return (1);
                         raddr = &rpool->cur->addr.p.dyn->pfid_addr4;
                         rmask = &rpool->cur->addr.p.dyn->pfid_mask4;
                        break;
#endif /* INET */
#ifdef INET6
                case AF_INET6:
                        if (rpool->cur->addr.p.dyn->pfid_acnt6 < 1 &&
                            (rpool->opts & PF_POOL_TYPEMASK) !=
                            PF_POOL_ROUNDROBIN)
                                return (1);
                        raddr = &rpool->cur->addr.p.dyn->pfid_addr6;
                        rmask = &rpool->cur->addr.p.dyn->pfid_mask6;
                        break;
#endif /* INET6 */
                }
        } else if (rpool->cur->addr.type == PF_ADDR_TABLE) {
                if ((rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_ROUNDROBIN)
                        return (1); /* unsupported */
        } else {
                raddr = &rpool->cur->addr.v.a.addr;
                rmask = &rpool->cur->addr.v.a.mask;
        }

        switch (rpool->opts & PF_POOL_TYPEMASK) {
        case PF_POOL_NONE:
                PF_ACPY(naddr, raddr, af);
                break;
        case PF_POOL_BITMASK:
                PF_POOLMASK(naddr, raddr, rmask, saddr, af);
                break;
        case PF_POOL_RANDOM:
                if (init_addr != NULL && PF_AZERO(init_addr, af)) {
                        switch (af) {
#ifdef INET
                        case AF_INET:
                                rpool->counter.addr32[0] =
                                    htonl(cprng_fast32());
                                break;
#endif /* INET */
#ifdef INET6
                        case AF_INET6:
                                if (rmask->addr32[3] != 0xffffffff)
                                        rpool->counter.addr32[3] =
                                            htonl(cprng_fast32());
                                else
                                        break;
                                if (rmask->addr32[2] != 0xffffffff)
                                        rpool->counter.addr32[2] =
                                            htonl(cprng_fast32());
                                else
                                        break;
                                if (rmask->addr32[1] != 0xffffffff)
                                        rpool->counter.addr32[1] =
                                            htonl(cprng_fast32());
                                else
                                        break;
                                if (rmask->addr32[0] != 0xffffffff)
                                        rpool->counter.addr32[0] =
                                            htonl(cprng_fast32());
                                break;
#endif /* INET6 */
                        }
                        PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af);
                        PF_ACPY(init_addr, naddr, af);

                } else {
                        PF_AINC(&rpool->counter, af);
                        PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af);
                }
                break;
        case PF_POOL_SRCHASH:
                pf_hash(saddr, (struct pf_addr *)&hash, &rpool->key, af);
                PF_POOLMASK(naddr, raddr, rmask, (struct pf_addr *)&hash, af);
                break;
        case PF_POOL_ROUNDROBIN:
                if (rpool->cur->addr.type == PF_ADDR_TABLE) {
                        if (!pfr_pool_get(rpool->cur->addr.p.tbl,
                            &rpool->tblidx, &rpool->counter,
                            &raddr, &rmask, af))
                                goto get_addr;
                } else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
                        if (!pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt,
                            &rpool->tblidx, &rpool->counter,
                            &raddr, &rmask, af))
                                goto get_addr;
                } else if (pf_match_addr(0, raddr, rmask, &rpool->counter, af))
                        goto get_addr;

        try_next:
                if ((rpool->cur = TAILQ_NEXT(rpool->cur, entries)) == NULL)
                        rpool->cur = TAILQ_FIRST(&rpool->list);
                if (rpool->cur->addr.type == PF_ADDR_TABLE) {
                        rpool->tblidx = -1;
                        if (pfr_pool_get(rpool->cur->addr.p.tbl,
                            &rpool->tblidx, &rpool->counter,
                            &raddr, &rmask, af)) {
                                /* table contains no address of type 'af' */
                                if (rpool->cur != acur)
                                        goto try_next;
                                return (1);
                        }
                } else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
                        rpool->tblidx = -1;
                        if (pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt,
                            &rpool->tblidx, &rpool->counter,
                            &raddr, &rmask, af)) {
                                /* table contains no address of type 'af' */
                                if (rpool->cur != acur)
                                        goto try_next;
                                return (1);
                        }
                } else {
                        raddr = &rpool->cur->addr.v.a.addr;
                        rmask = &rpool->cur->addr.v.a.mask;
                        PF_ACPY(&rpool->counter, raddr, af);
                }

        get_addr:
                PF_ACPY(naddr, &rpool->counter, af);
                if (init_addr != NULL && PF_AZERO(init_addr, af))
                        PF_ACPY(init_addr, naddr, af);
                PF_AINC(&rpool->counter, af);
                break;
        }
        if (*sn != NULL)
                PF_ACPY(&(*sn)->raddr, naddr, af);

        if (pf_status.debug >= PF_DEBUG_MISC &&
            (rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) {
                printf("pf_map_addr: selected address ");
                pf_print_host(naddr, 0, af);
                printf("\n");
        }

        return (0);
}

int
pf_get_sport(sa_family_t af, u_int8_t proto, struct pf_rule *r,
    struct pf_addr *saddr, struct pf_addr *daddr, u_int16_t dport,
    struct pf_addr *naddr, u_int16_t *nport, u_int16_t low, u_int16_t high,
    struct pf_src_node **sn)
{
        struct pf_state_key_cmp key;
        struct pf_addr          init_addr;
        u_int16_t               cut;

        bzero(&init_addr, sizeof(init_addr));
        if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn))
                return (1);

        if (proto == IPPROTO_ICMP) {
                low = 1;
                high = 65535;
        }

        do {
                key.af = af;
                key.proto = proto;
                PF_ACPY(&key.ext.addr, daddr, key.af);
                PF_ACPY(&key.gwy.addr, naddr, key.af);
                key.ext.port = dport;

                /*
                 * port search; start random, step;
                 * similar 2 portloop in inpcb_bind
                 */
                if (!(proto == IPPROTO_TCP || proto == IPPROTO_UDP ||
                    proto == IPPROTO_ICMP)) {
                        key.gwy.port = dport;
                        if (pf_find_state_all(&key, PF_EXT_GWY, NULL) == NULL)
                                return (0);
                } else if (low == 0 && high == 0) {
                        key.gwy.port = *nport;
                        if (pf_find_state_all(&key, PF_EXT_GWY, NULL) == NULL)
                                return (0);
                } else if (low == high) {
                        key.gwy.port = htons(low);
                        if (pf_find_state_all(&key, PF_EXT_GWY, NULL) == NULL) {
                                *nport = htons(low);
                                return (0);
                        }
                } else {
                        u_int16_t tmp;

                        if (low > high) {
                                tmp = low;
                                low = high;
                                high = tmp;
                        }
                        /* low < high */
                        cut = htonl(cprng_fast32()) % (1 + high - low) + low;
                        /* low <= cut <= high */
                        for (tmp = cut; tmp <= high; ++(tmp)) {
                                key.gwy.port = htons(tmp);
                                if (pf_find_state_all(&key, PF_EXT_GWY, NULL) ==
                                    NULL) {
                                        *nport = htons(tmp);
                                        return (0);
                                }
                        }
                        for (tmp = cut - 1; tmp >= low; --(tmp)) {
                                key.gwy.port = htons(tmp);
                                if (pf_find_state_all(&key, PF_EXT_GWY, NULL) ==
                                    NULL) {
                                        *nport = htons(tmp);
                                        return (0);
                                }
                        }
                }

                switch (r->rpool.opts & PF_POOL_TYPEMASK) {
                case PF_POOL_RANDOM:
                case PF_POOL_ROUNDROBIN:
                        if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn))
                                return (1);
                        break;
                case PF_POOL_NONE:
                case PF_POOL_SRCHASH:
                case PF_POOL_BITMASK:
                default:
                        return (1);
                }
        } while (! PF_AEQ(&init_addr, naddr, af) );

        return (1);                                     /* none available */
}

struct pf_rule *
pf_match_translation(struct pf_pdesc *pd, struct mbuf *m, int off,
    int direction, struct pfi_kif *kif, struct pf_addr *saddr, u_int16_t sport,
    struct pf_addr *daddr, u_int16_t dport, int rs_num)
{
        struct pf_rule          *r, *rm = NULL;
        struct pf_ruleset       *ruleset = NULL;
        int                      tag = -1;
        int                      rtableid = -1;
        int                      asd = 0;

        r = TAILQ_FIRST(pf_main_ruleset.rules[rs_num].active.ptr);
        while (r && rm == NULL) {
                struct pf_rule_addr     *src = NULL, *dst = NULL;
                struct pf_addr_wrap     *xdst = NULL;

                if (r->action == PF_BINAT && direction == PF_IN) {
                        src = &r->dst;
                        if (r->rpool.cur != NULL)
                                xdst = &r->rpool.cur->addr;
                } else {
                        src = &r->src;
                        dst = &r->dst;
                }

                r->evaluations++;
                if (pfi_kif_match(r->kif, kif) == r->ifnot)
                        r = r->skip[PF_SKIP_IFP].ptr;
                else if (r->direction && r->direction != direction)
                        r = r->skip[PF_SKIP_DIR].ptr;
                else if (r->af && r->af != pd->af)
                        r = r->skip[PF_SKIP_AF].ptr;
                else if (r->proto && r->proto != pd->proto)
                        r = r->skip[PF_SKIP_PROTO].ptr;
                else if (PF_MISMATCHAW(&src->addr, saddr, pd->af,
                    src->neg, kif))
                        r = r->skip[src == &r->src ? PF_SKIP_SRC_ADDR :
                            PF_SKIP_DST_ADDR].ptr;
                else if (src->port_op && !pf_match_port(src->port_op,
                    src->port[0], src->port[1], sport))
                        r = r->skip[src == &r->src ? PF_SKIP_SRC_PORT :
                            PF_SKIP_DST_PORT].ptr;
                else if (dst != NULL &&
                    PF_MISMATCHAW(&dst->addr, daddr, pd->af, dst->neg, NULL))
                        r = r->skip[PF_SKIP_DST_ADDR].ptr;
                else if (xdst != NULL && PF_MISMATCHAW(xdst, daddr, pd->af,
                    0, NULL))
                        r = TAILQ_NEXT(r, entries);
                else if (dst != NULL && dst->port_op &&
                    !pf_match_port(dst->port_op, dst->port[0],
                    dst->port[1], dport))
                        r = r->skip[PF_SKIP_DST_PORT].ptr;
                else if (r->match_tag && !pf_match_tag(m, r, &tag))
                        r = TAILQ_NEXT(r, entries);
                else if (r->os_fingerprint != PF_OSFP_ANY && (pd->proto !=
                    IPPROTO_TCP || !pf_osfp_match(pf_osfp_fingerprint(pd, m,
                    off, pd->hdr.tcp), r->os_fingerprint)))
                        r = TAILQ_NEXT(r, entries);
                else {
                        if (r->tag)
                                tag = r->tag;
                        if (r->rtableid >= 0)
                                rtableid = r->rtableid;
                        if (r->anchor == NULL) {
                                rm = r;
                        } else
                                pf_step_into_anchor(&asd, &ruleset, rs_num,
                                    &r, NULL, NULL);
                }
                if (r == NULL)
                        pf_step_out_of_anchor(&asd, &ruleset, rs_num, &r,
                            NULL, NULL);
        }
        if (pf_tag_packet(m, tag, rtableid))
                return (NULL);
        if (rm != NULL && (rm->action == PF_NONAT ||
            rm->action == PF_NORDR || rm->action == PF_NOBINAT))
                return (NULL);
        return (rm);
}

struct pf_rule *
pf_get_translation(struct pf_pdesc *pd, struct mbuf *m, int off, int direction,
    struct pfi_kif *kif, struct pf_src_node **sn,
    struct pf_addr *saddr, u_int16_t sport,
    struct pf_addr *daddr, u_int16_t dport,
    struct pf_addr *naddr, u_int16_t *nport)
{
        struct pf_rule  *r = NULL;

        if (direction == PF_OUT) {
                r = pf_match_translation(pd, m, off, direction, kif, saddr,
                    sport, daddr, dport, PF_RULESET_BINAT);
                if (r == NULL)
                        r = pf_match_translation(pd, m, off, direction, kif,
                            saddr, sport, daddr, dport, PF_RULESET_NAT);
        } else {
                r = pf_match_translation(pd, m, off, direction, kif, saddr,
                    sport, daddr, dport, PF_RULESET_RDR);
                if (r == NULL)
                        r = pf_match_translation(pd, m, off, direction, kif,
                            saddr, sport, daddr, dport, PF_RULESET_BINAT);
        }

        if (r != NULL) {
                switch (r->action) {
                case PF_NONAT:
                case PF_NOBINAT:
                case PF_NORDR:
                        return (NULL);
                case PF_NAT:
                        if (pf_get_sport(pd->af, pd->proto, r, saddr,
                            daddr, dport, naddr, nport, r->rpool.proxy_port[0],
                            r->rpool.proxy_port[1], sn)) {
                                DPFPRINTF(PF_DEBUG_MISC,
                                    ("pf: NAT proxy port allocation "
                                    "(%u-%u) failed\n",
                                    r->rpool.proxy_port[0],
                                    r->rpool.proxy_port[1]));
                                return (NULL);
                        }
                        break;
                case PF_BINAT:
                        switch (direction) {
                        case PF_OUT:
                                if (r->rpool.cur->addr.type == PF_ADDR_DYNIFTL){
                                        switch (pd->af) {
#ifdef INET
                                        case AF_INET:
                                                if (r->rpool.cur->addr.p.dyn->
                                                    pfid_acnt4 < 1)
                                                        return (NULL);
                                                PF_POOLMASK(naddr,
                                                    &r->rpool.cur->addr.p.dyn->
                                                    pfid_addr4,
                                                    &r->rpool.cur->addr.p.dyn->
                                                    pfid_mask4,
                                                    saddr, AF_INET);
                                                break;
#endif /* INET */
#ifdef INET6
                                        case AF_INET6:
                                                if (r->rpool.cur->addr.p.dyn->
                                                    pfid_acnt6 < 1)
                                                        return (NULL);
                                                PF_POOLMASK(naddr,
                                                    &r->rpool.cur->addr.p.dyn->
                                                    pfid_addr6,
                                                    &r->rpool.cur->addr.p.dyn->
                                                    pfid_mask6,
                                                    saddr, AF_INET6);
                                                break;
#endif /* INET6 */
                                        }
                                } else
                                        PF_POOLMASK(naddr,
                                            &r->rpool.cur->addr.v.a.addr,
                                            &r->rpool.cur->addr.v.a.mask,
                                            saddr, pd->af);
                                break;
                        case PF_IN:
                                if (r->src.addr.type == PF_ADDR_DYNIFTL) {
                                        switch (pd->af) {
#ifdef INET
                                        case AF_INET:
                                                if (r->src.addr.p.dyn->
                                                    pfid_acnt4 < 1)
                                                        return (NULL);
                                                PF_POOLMASK(naddr,
                                                    &r->src.addr.p.dyn->
                                                    pfid_addr4,
                                                    &r->src.addr.p.dyn->
                                                    pfid_mask4,
                                                    daddr, AF_INET);
                                                break;
#endif /* INET */
#ifdef INET6
                                        case AF_INET6:
                                                if (r->src.addr.p.dyn->
                                                    pfid_acnt6 < 1)
                                                        return (NULL);
                                                PF_POOLMASK(naddr,
                                                    &r->src.addr.p.dyn->
                                                    pfid_addr6,
                                                    &r->src.addr.p.dyn->
                                                    pfid_mask6,
                                                    daddr, AF_INET6);
                                                break;
#endif /* INET6 */
                                        }
                                } else
                                        PF_POOLMASK(naddr,
                                            &r->src.addr.v.a.addr,
                                            &r->src.addr.v.a.mask, daddr,
                                            pd->af);
                                break;
                        }
                        break;
                case PF_RDR: {
                        if (pf_map_addr(pd->af, r, saddr, naddr, NULL, sn))
                                return (NULL);
                        if ((r->rpool.opts & PF_POOL_TYPEMASK) ==
                            PF_POOL_BITMASK)
                                PF_POOLMASK(naddr, naddr,
                                    &r->rpool.cur->addr.v.a.mask, daddr,
                                    pd->af);

                        if (r->rpool.proxy_port[1]) {
                                u_int32_t       tmp_nport;

                                tmp_nport = ((ntohs(dport) -
                                    ntohs(r->dst.port[0])) %
                                    (r->rpool.proxy_port[1] -
                                    r->rpool.proxy_port[0] + 1)) +
                                    r->rpool.proxy_port[0];

                                /* wrap around if necessary */
                                if (tmp_nport > 65535)
                                        tmp_nport -= 65535;
                                *nport = htons((u_int16_t)tmp_nport);
                        } else if (r->rpool.proxy_port[0])
                                *nport = htons(r->rpool.proxy_port[0]);
                        break;
                }
                default:
                        return (NULL);
                }
        }

        return (r);
}

int
pf_socket_lookup(int direction, struct pf_pdesc *pd)
{
        struct pf_addr          *saddr, *daddr;
        u_int16_t                sport, dport;
        struct inpcbtable       *tb;
        struct inpcb            *inp = NULL;
        struct socket           *so = NULL;
#define in6p inp
#define in6p_socket inp_socket

        if (pd == NULL)
                return (-1);
        pd->lookup.uid = UID_MAX;
        pd->lookup.gid = GID_MAX;
        pd->lookup.pid = NO_PID;
        switch (pd->proto) {
        case IPPROTO_TCP:
                if (pd->hdr.tcp == NULL)
                        return (-1);
                sport = pd->hdr.tcp->th_sport;
                dport = pd->hdr.tcp->th_dport;
                tb = &tcbtable;
                break;
        case IPPROTO_UDP:
                if (pd->hdr.udp == NULL)
                        return (-1);
                sport = pd->hdr.udp->uh_sport;
                dport = pd->hdr.udp->uh_dport;
                tb = &udbtable;
                break;
        default:
                return (-1);
        }
        if (direction == PF_IN) {
                saddr = pd->src;
                daddr = pd->dst;
        } else {
                u_int16_t       p;

                p = sport;
                sport = dport;
                dport = p;
                saddr = pd->dst;
                daddr = pd->src;
        }
        switch (pd->af) {

#ifdef __NetBSD__
#define in_pcbhashlookup(tbl, saddr, sport, daddr, dport) \
    inpcb_lookup(tbl, saddr, sport, daddr, dport, NULL)
#define in6_pcbhashlookup(tbl, saddr, sport, daddr, dport) \
    in6pcb_lookup(tbl, saddr, sport, daddr, dport, 0, NULL)
#define in_pcblookup_listen(tbl, addr, port, zero) \
    inpcb_lookup_bound(tbl, addr, port)
#define in6_pcblookup_listen(tbl, addr, port, zero) \
    in6pcb_lookup_bound(tbl, addr, port, zero)
#endif
        
#ifdef INET
        case AF_INET:
                inp = in_pcbhashlookup(tb, saddr->v4, sport, daddr->v4, dport);
                if (inp == NULL) {
                        inp = in_pcblookup_listen(tb, daddr->v4, dport, 0);
                        if (inp == NULL)
                                return (-1);
                }
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                in6p = in6_pcbhashlookup(tb, &saddr->v6, sport, &daddr->v6,
                    dport);
                if (inp == NULL) {
                        in6p = in6_pcblookup_listen(tb, &daddr->v6, dport, 0);
                        if (inp == NULL)
                                return (-1);
                }
                break;
#endif /* INET6 */

        default:
                return (-1);
        }

#ifdef __NetBSD__
        switch (pd->af) {
#ifdef INET
        case AF_INET:
                so = inp->inp_socket;
                break;
#endif
#ifdef INET6
        case AF_INET6:
                so = in6p->in6p_socket;
                break;
#endif /* INET6 */
        }
        if (so == NULL || so->so_cred == NULL)
                return -1;
        pd->lookup.uid = kauth_cred_geteuid(so->so_cred);
        pd->lookup.gid = kauth_cred_getegid(so->so_cred);
#else
        so = inp->inp_socket;
        pd->lookup.uid = so->so_euid;
        pd->lookup.gid = so->so_egid;
#endif /* !__NetBSD__ */
        pd->lookup.pid = so->so_cpid;
        return (1);
}

u_int8_t
pf_get_wscale(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
{
        int              hlen;
        u_int8_t         hdr[60];
        u_int8_t        *opt, optlen;
        u_int8_t         wscale = 0;

        hlen = th_off << 2;             /* hlen <= sizeof(hdr) */
        if (hlen <= sizeof(struct tcphdr))
                return (0);
        if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
                return (0);
        opt = hdr + sizeof(struct tcphdr);
        hlen -= sizeof(struct tcphdr);
        while (hlen >= 3) {
                switch (*opt) {
                case TCPOPT_EOL:
                case TCPOPT_NOP:
                        ++opt;
                        --hlen;
                        break;
                case TCPOPT_WINDOW:
                        wscale = opt[2];
                        if (wscale > TCP_MAX_WINSHIFT)
                                wscale = TCP_MAX_WINSHIFT;
                        wscale |= PF_WSCALE_FLAG;
                        /* FALLTHROUGH */
                default:
                        optlen = opt[1];
                        if (optlen < 2)
                                optlen = 2;
                        hlen -= optlen;
                        opt += optlen;
                        break;
                }
        }
        return (wscale);
}

u_int16_t
pf_get_mss(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
{
        int              hlen;
        u_int8_t         hdr[60];
        u_int8_t        *opt, optlen;
        u_int16_t        mss = tcp_mssdflt;

        hlen = th_off << 2;     /* hlen <= sizeof(hdr) */
        if (hlen <= sizeof(struct tcphdr))
                return (0);
        if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
                return (0);
        opt = hdr + sizeof(struct tcphdr);
        hlen -= sizeof(struct tcphdr);
        while (hlen >= TCPOLEN_MAXSEG) {
                switch (*opt) {
                case TCPOPT_EOL:
                case TCPOPT_NOP:
                        ++opt;
                        --hlen;
                        break;
                case TCPOPT_MAXSEG:
                        bcopy((void *)(opt + 2), (void *)&mss, 2);
                        NTOHS(mss);
                        /* FALLTHROUGH */
                default:
                        optlen = opt[1];
                        if (optlen < 2)
                                optlen = 2;
                        hlen -= optlen;
                        opt += optlen;
                        break;
                }
        }
        return (mss);
}

u_int16_t
pf_calc_mss(struct pf_addr *addr, sa_family_t af, u_int16_t offer)
{
        union {
                struct sockaddr         dst;
                struct sockaddr_in      dst4;
                struct sockaddr_in6     dst6;
        } u;
        struct route             ro;
        struct route            *rop = &ro;
        struct rtentry          *rt;
        int                      hlen;
        u_int16_t                mss = tcp_mssdflt;

        hlen = 0;       /* XXXGCC -Wuninitialized m68k */

        memset(&ro, 0, sizeof(ro));
        switch (af) {
#ifdef INET
        case AF_INET:
                hlen = sizeof(struct ip);
                sockaddr_in_init(&u.dst4, &addr->v4, 0);
                rtcache_setdst(rop, &u.dst);
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                hlen = sizeof(struct ip6_hdr);
                sockaddr_in6_init(&u.dst6, &addr->v6, 0, 0, 0);
                rtcache_setdst(rop, &u.dst);
                break;
#endif /* INET6 */
        }

#ifndef __NetBSD__
        rtalloc_noclone(rop, NO_CLONING);
        if ((rt = ro->ro_rt) != NULL) {
                mss = rt->rt_ifp->if_mtu - hlen - sizeof(struct tcphdr);
                mss = uimax(tcp_mssdflt, mss);
        }
#else
        if ((rt = rtcache_init_noclone(rop)) != NULL) {
                mss = rt->rt_ifp->if_mtu - hlen - sizeof(struct tcphdr);
                mss = uimax(tcp_mssdflt, mss);
                rtcache_unref(rt, rop);
        }
        rtcache_free(rop);
#endif
        mss = uimin(mss, offer);
        mss = uimax(mss, 64);           /* sanity - at least max opt space */
        return (mss);
}

void
pf_set_rt_ifp(struct pf_state *s, struct pf_addr *saddr)
{
        struct pf_rule *r = s->rule.ptr;

        s->rt_kif = NULL;
        if (!r->rt || r->rt == PF_FASTROUTE)
                return;
        switch (s->state_key->af) {
#ifdef INET
        case AF_INET:
                pf_map_addr(AF_INET, r, saddr, &s->rt_addr, NULL,
                    &s->nat_src_node);
                s->rt_kif = r->rpool.cur->kif;
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                pf_map_addr(AF_INET6, r, saddr, &s->rt_addr, NULL,
                    &s->nat_src_node);
                s->rt_kif = r->rpool.cur->kif;
                break;
#endif /* INET6 */
        }
}

void
pf_attach_state(struct pf_state_key *sk, struct pf_state *s, int tail)
{
        s->state_key = sk;
        sk->refcnt++;

        /* list is sorted, if-bound states before floating */
        if (tail)
                TAILQ_INSERT_TAIL(&sk->states, s, next);
        else
                TAILQ_INSERT_HEAD(&sk->states, s, next);
}

void
pf_detach_state(struct pf_state *s, int flags)
{
        struct pf_state_key     *sk = s->state_key;

        if (sk == NULL)
                return;

        s->state_key = NULL;
        TAILQ_REMOVE(&sk->states, s, next);
        if (--sk->refcnt == 0) {
                if (!(flags & PF_DT_SKIP_EXTGWY))
                        RB_REMOVE(pf_state_tree_ext_gwy,
                            &pf_statetbl_ext_gwy, sk);
                if (!(flags & PF_DT_SKIP_LANEXT))
                        RB_REMOVE(pf_state_tree_lan_ext,
                            &pf_statetbl_lan_ext, sk);
                pool_put(&pf_state_key_pl, sk);
        }
}

struct pf_state_key *
pf_alloc_state_key(struct pf_state *s)
{
        struct pf_state_key     *sk;

        if ((sk = pool_get(&pf_state_key_pl, PR_NOWAIT)) == NULL)
                return (NULL);
        bzero(sk, sizeof(*sk));
        TAILQ_INIT(&sk->states);
        pf_attach_state(sk, s, 0);

        return (sk);
}

int
pf_test_rule(struct pf_rule **rm, struct pf_state **sm, int direction,
    struct pfi_kif *kif, struct mbuf *m, int off, void *h,
    struct pf_pdesc *pd, struct pf_rule **am, struct pf_ruleset **rsm,
    struct ifqueue *ifq)
{
        struct pf_rule          *nr = NULL;
        struct pf_addr          *saddr = pd->src, *daddr = pd->dst;
        u_int16_t                bport, nport = 0;
        sa_family_t              af = pd->af;
        struct pf_rule          *r, *a = NULL;
        struct pf_ruleset       *ruleset = NULL;
        struct pf_src_node      *nsn = NULL;
        struct tcphdr           *th = pd->hdr.tcp;
        u_short                  reason;
        int                      rewrite = 0, hdrlen = 0;
        int                      tag = -1, rtableid = -1;
        int                      asd = 0;
        int                      match = 0;
        int                      state_icmp = 0;
        u_int16_t                mss = tcp_mssdflt;
        u_int16_t                sport, dport;
        u_int8_t                 icmptype = 0, icmpcode = 0;

        if (direction == PF_IN && pf_check_congestion(ifq)) {
                REASON_SET_NOPTR(&reason, PFRES_CONGEST);
                return (PF_DROP);
        }

        sport = dport = hdrlen = 0;

        switch (pd->proto) {
        case IPPROTO_TCP:
                sport = th->th_sport;
                dport = th->th_dport;
                hdrlen = sizeof(*th);
                break;
        case IPPROTO_UDP:
                sport = pd->hdr.udp->uh_sport;
                dport = pd->hdr.udp->uh_dport;
                hdrlen = sizeof(*pd->hdr.udp);
                break;
#ifdef INET
        case IPPROTO_ICMP:
                if (pd->af != AF_INET)
                        break;
                sport = dport = pd->hdr.icmp->icmp_id;
                icmptype = pd->hdr.icmp->icmp_type;
                icmpcode = pd->hdr.icmp->icmp_code;

                if (icmptype == ICMP_UNREACH ||
                    icmptype == ICMP_SOURCEQUENCH ||
                    icmptype == ICMP_REDIRECT ||
                    icmptype == ICMP_TIMXCEED ||
                    icmptype == ICMP_PARAMPROB)
                        state_icmp++;
                break;
#endif /* INET */

#ifdef INET6
        case IPPROTO_ICMPV6:
                if (pd->af != AF_INET6)
                        break;
                sport = dport = pd->hdr.icmp6->icmp6_id;
                hdrlen = sizeof(*pd->hdr.icmp6);
                icmptype = pd->hdr.icmp6->icmp6_type;
                icmpcode = pd->hdr.icmp6->icmp6_code;

                if (icmptype == ICMP6_DST_UNREACH ||
                    icmptype == ICMP6_PACKET_TOO_BIG ||
                    icmptype == ICMP6_TIME_EXCEEDED ||
                    icmptype == ICMP6_PARAM_PROB)
                        state_icmp++;
                break;
#endif /* INET6 */
        }

        r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);

        if (direction == PF_OUT) {
                bport = nport = sport;
                /* check outgoing packet for BINAT/NAT */
                if ((nr = pf_get_translation(pd, m, off, PF_OUT, kif, &nsn,
                    saddr, sport, daddr, dport, &pd->naddr, &nport)) != NULL) {
                        PF_ACPY(&pd->baddr, saddr, af);
                        switch (pd->proto) {
                        case IPPROTO_TCP:
                                pf_change_ap(saddr, &th->th_sport, pd->ip_sum,
                                    &th->th_sum, &pd->naddr, nport, 0, af);
                                sport = th->th_sport;
                                rewrite++;
                                break;
                        case IPPROTO_UDP:
                                pf_change_ap(saddr, &pd->hdr.udp->uh_sport,
                                    pd->ip_sum, &pd->hdr.udp->uh_sum,
                                    &pd->naddr, nport, 1, af);
                                sport = pd->hdr.udp->uh_sport;
                                rewrite++;
                                break;
#ifdef INET
                        case IPPROTO_ICMP:
                                pf_change_a(&saddr->v4.s_addr, pd->ip_sum,
                                    pd->naddr.v4.s_addr, 0);
                                pd->hdr.icmp->icmp_cksum = pf_cksum_fixup(
                                    pd->hdr.icmp->icmp_cksum, sport, nport, 0);
                                pd->hdr.icmp->icmp_id = nport;
                                m_copyback(m, off, ICMP_MINLEN, pd->hdr.icmp);
                                break;
#endif /* INET */
#ifdef INET6
                        case IPPROTO_ICMPV6:
                                pf_change_a6(saddr, &pd->hdr.icmp6->icmp6_cksum,
                                    &pd->naddr, 0);
                                rewrite++;
                                break;
#endif /* INET */
                        default:
                                switch (af) {
#ifdef INET
                                case AF_INET:
                                        pf_change_a(&saddr->v4.s_addr,
                                            pd->ip_sum, pd->naddr.v4.s_addr, 0);
                                        break;
#endif /* INET */
#ifdef INET6
                                case AF_INET6:
                                        PF_ACPY(saddr, &pd->naddr, af);
                                        break;
#endif /* INET */
                                }
                                break;
                        }

                        if (nr->natpass)
                                r = NULL;
                        pd->nat_rule = nr;
                }
        } else {
                bport = nport = dport;
                /* check incoming packet for BINAT/RDR */
                if ((nr = pf_get_translation(pd, m, off, PF_IN, kif, &nsn,
                    saddr, sport, daddr, dport, &pd->naddr, &nport)) != NULL) {
                        PF_ACPY(&pd->baddr, daddr, af);
                        switch (pd->proto) {
                        case IPPROTO_TCP:
                                pf_change_ap(daddr, &th->th_dport, pd->ip_sum,
                                    &th->th_sum, &pd->naddr, nport, 0, af);
                                dport = th->th_dport;
                                rewrite++;
                                break;
                        case IPPROTO_UDP:
                                pf_change_ap(daddr, &pd->hdr.udp->uh_dport,
                                    pd->ip_sum, &pd->hdr.udp->uh_sum,
                                    &pd->naddr, nport, 1, af);
                                dport = pd->hdr.udp->uh_dport;
                                rewrite++;
                                break;
#ifdef INET
                        case IPPROTO_ICMP:
                                pf_change_a(&daddr->v4.s_addr, pd->ip_sum,
                                    pd->naddr.v4.s_addr, 0);
                                break;
#endif /* INET */
#ifdef INET6
                        case IPPROTO_ICMPV6:
                                pf_change_a6(daddr, &pd->hdr.icmp6->icmp6_cksum,
                                    &pd->naddr, 0);
                                rewrite++;
                                break;
#endif /* INET6 */
                        default:
                                switch (af) {
#ifdef INET
                                case AF_INET:
                                        pf_change_a(&daddr->v4.s_addr,
                                            pd->ip_sum, pd->naddr.v4.s_addr, 0);
                                        break;
#endif /* INET */
#ifdef INET6
                                case AF_INET6:
                                        PF_ACPY(daddr, &pd->naddr, af);
                                        break;
#endif /* INET */
                                }
                                break;
                        }

                        if (nr->natpass)
                                r = NULL;
                        pd->nat_rule = nr;
                }
        }

        while (r != NULL) {
                r->evaluations++;
                if (pfi_kif_match(r->kif, kif) == r->ifnot)
                        r = r->skip[PF_SKIP_IFP].ptr;
                else if (r->direction && r->direction != direction)
                        r = r->skip[PF_SKIP_DIR].ptr;
                else if (r->af && r->af != af)
                        r = r->skip[PF_SKIP_AF].ptr;
                else if (r->proto && r->proto != pd->proto)
                        r = r->skip[PF_SKIP_PROTO].ptr;
                else if (PF_MISMATCHAW(&r->src.addr, saddr, af,
                    r->src.neg, kif))
                        r = r->skip[PF_SKIP_SRC_ADDR].ptr;
                /* tcp/udp only. port_op always 0 in other cases */
                else if (r->src.port_op && !pf_match_port(r->src.port_op,
                    r->src.port[0], r->src.port[1], sport))
                        r = r->skip[PF_SKIP_SRC_PORT].ptr;
                else if (PF_MISMATCHAW(&r->dst.addr, daddr, af,
                    r->dst.neg, NULL))
                        r = r->skip[PF_SKIP_DST_ADDR].ptr;
                /* tcp/udp only. port_op always 0 in other cases */
                else if (r->dst.port_op && !pf_match_port(r->dst.port_op,
                    r->dst.port[0], r->dst.port[1], dport))
                        r = r->skip[PF_SKIP_DST_PORT].ptr;
                /* icmp only. type always 0 in other cases */
                else if (r->type && r->type != icmptype + 1)
                        r = TAILQ_NEXT(r, entries);
                /* icmp only. type always 0 in other cases */
                else if (r->code && r->code != icmpcode + 1)
                        r = TAILQ_NEXT(r, entries);
                else if (r->tos && !(r->tos == pd->tos))
                        r = TAILQ_NEXT(r, entries);
                else if (r->rule_flag & PFRULE_FRAGMENT)
                        r = TAILQ_NEXT(r, entries);
                else if (pd->proto == IPPROTO_TCP &&
                    (r->flagset & th->th_flags) != r->flags)
                        r = TAILQ_NEXT(r, entries);
                /* tcp/udp only. uid.op always 0 in other cases */
                else if (r->uid.op && (pd->lookup.done || (pd->lookup.done =
                    pf_socket_lookup(direction, pd), 1)) &&
                    !pf_match_uid(r->uid.op, r->uid.uid[0], r->uid.uid[1],
                    pd->lookup.uid))
                        r = TAILQ_NEXT(r, entries);
                /* tcp/udp only. gid.op always 0 in other cases */
                else if (r->gid.op && (pd->lookup.done || (pd->lookup.done =
                    pf_socket_lookup(direction, pd), 1)) &&
                    !pf_match_gid(r->gid.op, r->gid.gid[0], r->gid.gid[1],
                    pd->lookup.gid))
                        r = TAILQ_NEXT(r, entries);
                else if (r->prob && r->prob <= cprng_fast32())
                        r = TAILQ_NEXT(r, entries);
                else if (r->match_tag && !pf_match_tag(m, r, &tag))
                        r = TAILQ_NEXT(r, entries);
                else if (r->os_fingerprint != PF_OSFP_ANY &&
                    (pd->proto != IPPROTO_TCP || !pf_osfp_match(
                    pf_osfp_fingerprint(pd, m, off, th),
                    r->os_fingerprint)))
                        r = TAILQ_NEXT(r, entries);
                else {
                        if (r->tag)
                                tag = r->tag;
                        if (r->rtableid >= 0)
                                rtableid = r->rtableid;
                        if (r->anchor == NULL) {
                                match = 1;
                                *rm = r;
                                *am = a;
                                *rsm = ruleset;
                                if ((*rm)->quick)
                                        break;
                                r = TAILQ_NEXT(r, entries);
                        } else
                                pf_step_into_anchor(&asd, &ruleset,
                                    PF_RULESET_FILTER, &r, &a, &match);
                }
                if (r == NULL && pf_step_out_of_anchor(&asd, &ruleset,
                    PF_RULESET_FILTER, &r, &a, &match))
                        break;
        }
        r = *rm;
        a = *am;
        ruleset = *rsm;

        REASON_SET_NOPTR(&reason, PFRES_MATCH);

        if (r->log || (nr != NULL && nr->log)) {
                if (rewrite)
                        m_copyback(m, off, hdrlen, pd->hdr.any);
                PFLOG_PACKET(kif, h, m, af, direction, reason, r->log ? r : nr,
                    a, ruleset, pd);
        }

        if (r->keep_state && pf_state_lock) {
                REASON_SET_NOPTR(&reason, PFRES_STATELOCKED);
                return PF_DROP;
        }

        if ((r->action == PF_DROP) &&
            ((r->rule_flag & PFRULE_RETURNRST) ||
            (r->rule_flag & PFRULE_RETURNICMP) ||
            (r->rule_flag & PFRULE_RETURN))) {
                /* undo NAT changes, if they have taken place */
                if (nr != NULL) {
                        if (direction == PF_OUT) {
                                switch (pd->proto) {
                                case IPPROTO_TCP:
                                        pf_change_ap(saddr, &th->th_sport,
                                            pd->ip_sum, &th->th_sum,
                                            &pd->baddr, bport, 0, af);
                                        sport = th->th_sport;
                                        rewrite++;
                                        break;
                                case IPPROTO_UDP:
                                        pf_change_ap(saddr,
                                            &pd->hdr.udp->uh_sport, pd->ip_sum,
                                            &pd->hdr.udp->uh_sum, &pd->baddr,
                                            bport, 1, af);
                                        sport = pd->hdr.udp->uh_sport;
                                        rewrite++;
                                        break;
                                case IPPROTO_ICMP:
#ifdef INET6
                                case IPPROTO_ICMPV6:
#endif
                                        /* nothing! */
                                        break;
                                default:
                                        switch (af) {
                                        case AF_INET:
                                                pf_change_a(&saddr->v4.s_addr,
                                                    pd->ip_sum,
                                                    pd->baddr.v4.s_addr, 0);
                                                break;
                                        case AF_INET6:
                                                PF_ACPY(saddr, &pd->baddr, af);
                                                break;
                                        }
                                }
                        } else {
                                switch (pd->proto) {
                                case IPPROTO_TCP:
                                        pf_change_ap(daddr, &th->th_dport,
                                            pd->ip_sum, &th->th_sum,
                                            &pd->baddr, bport, 0, af);
                                        dport = th->th_dport;
                                        rewrite++;
                                        break;
                                case IPPROTO_UDP:
                                        pf_change_ap(daddr,
                                            &pd->hdr.udp->uh_dport, pd->ip_sum,
                                            &pd->hdr.udp->uh_sum, &pd->baddr,
                                            bport, 1, af);
                                        dport = pd->hdr.udp->uh_dport;
                                        rewrite++;
                                        break;
                                case IPPROTO_ICMP:
#ifdef INET6
                                case IPPROTO_ICMPV6:
#endif
                                        /* nothing! */
                                        break;
                                default:
                                        switch (af) {
                                        case AF_INET:
                                                pf_change_a(&daddr->v4.s_addr,
                                                    pd->ip_sum,
                                                    pd->baddr.v4.s_addr, 0);
                                                break;
                                        case AF_INET6:
                                                PF_ACPY(daddr, &pd->baddr, af);
                                                break;
                                        }
                                }
                        }
                }
                if (pd->proto == IPPROTO_TCP &&
                    ((r->rule_flag & PFRULE_RETURNRST) ||
                    (r->rule_flag & PFRULE_RETURN)) &&
                    !(th->th_flags & TH_RST)) {
                        u_int32_t        ack = ntohl(th->th_seq) + pd->p_len;
                        struct ip       *hip = mtod(m, struct ip *);

#ifdef __NetBSD__
                        if (pf_check_proto_cksum(m, direction, off,
                            ntohs(hip->ip_len) - off, IPPROTO_TCP, AF_INET))
#else
                        if (pf_check_proto_cksum(m, off,
                            ntohs(hip->ip_len) - off, IPPROTO_TCP, AF_INET))
#endif /* !__NetBSD__ */
                                REASON_SET_NOPTR(&reason, PFRES_PROTCKSUM);
                        else {
                                if (th->th_flags & TH_SYN)
                                        ack++;
                                if (th->th_flags & TH_FIN)
                                        ack++;
                                pf_send_tcp(r, af, pd->dst,
                                    pd->src, th->th_dport, th->th_sport,
                                    ntohl(th->th_ack), ack, TH_RST|TH_ACK, 0, 0,
                                    r->return_ttl, 1, 0, pd->eh, kif->pfik_ifp);
                        }
                } else if ((af == AF_INET) && r->return_icmp)
                        pf_send_icmp(m, r->return_icmp >> 8,
                            r->return_icmp & 255, af, r);
                else if ((af == AF_INET6) && r->return_icmp6)
                        pf_send_icmp(m, r->return_icmp6 >> 8,
                            r->return_icmp6 & 255, af, r);
        }

        if (r->action == PF_DROP)
                return (PF_DROP);

        if (pf_tag_packet(m, tag, rtableid)) {
                REASON_SET_NOPTR(&reason, PFRES_MEMORY);
                return (PF_DROP);
        }

        if (!state_icmp && (r->keep_state || nr != NULL ||
            (pd->flags & PFDESC_TCP_NORM))) {
                /* create new state */
                u_int16_t        len;
                struct pf_state *s = NULL;
                struct pf_state_key *sk = NULL;
                struct pf_src_node *sn = NULL;

                /* check maximums */
                if (r->max_states && (r->states >= r->max_states)) {
                        pf_status.lcounters[LCNT_STATES]++;
                        REASON_SET_NOPTR(&reason, PFRES_MAXSTATES);
                        goto cleanup;
                }
                /* src node for filter rule */
                if ((r->rule_flag & PFRULE_SRCTRACK ||
                    r->rpool.opts & PF_POOL_STICKYADDR) &&
                    pf_insert_src_node(&sn, r, saddr, af) != 0) {
                        REASON_SET_NOPTR(&reason, PFRES_SRCLIMIT);
                        goto cleanup;
                }
                /* src node for translation rule */
                if (nr != NULL && (nr->rpool.opts & PF_POOL_STICKYADDR) &&
                    ((direction == PF_OUT &&
                    pf_insert_src_node(&nsn, nr, &pd->baddr, af) != 0) ||
                    (pf_insert_src_node(&nsn, nr, saddr, af) != 0))) {
                        REASON_SET_NOPTR(&reason, PFRES_SRCLIMIT);
                        goto cleanup;
                }
                s = pool_get(&pf_state_pl, PR_NOWAIT);
                if (s == NULL) {
                        REASON_SET_NOPTR(&reason, PFRES_MEMORY);
cleanup:
                        if (sn != NULL && sn->states == 0 && sn->expire == 0) {
                                RB_REMOVE(pf_src_tree, &tree_src_tracking, sn);
                                pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++;
                                pf_status.src_nodes--;
                                pool_put(&pf_src_tree_pl, sn);
                        }
                        if (nsn != sn && nsn != NULL && nsn->states == 0 &&
                            nsn->expire == 0) {
                                RB_REMOVE(pf_src_tree, &tree_src_tracking, nsn);
                                pf_status.scounters[SCNT_SRC_NODE_REMOVALS]++;
                                pf_status.src_nodes--;
                                pool_put(&pf_src_tree_pl, nsn);
                        }
                        if (sk != NULL) {
                                pool_put(&pf_state_key_pl, sk);
                        }
                        return (PF_DROP);
                }
                bzero(s, sizeof(*s));
                s->rule.ptr = r;
                s->nat_rule.ptr = nr;
                s->anchor.ptr = a;
                STATE_INC_COUNTERS(s);
                s->allow_opts = r->allow_opts;
                s->log = r->log & PF_LOG_ALL;
                if (nr != NULL)
                        s->log |= nr->log & PF_LOG_ALL;
                switch (pd->proto) {
                case IPPROTO_TCP:
                        len = pd->tot_len - off - (th->th_off << 2);
                        s->src.seqlo = ntohl(th->th_seq);
                        s->src.seqhi = s->src.seqlo + len + 1;
                        if ((th->th_flags & (TH_SYN|TH_ACK)) ==
                        TH_SYN && r->keep_state == PF_STATE_MODULATE) {
                                /* Generate sequence number modulator */
                                while ((s->src.seqdiff =
                                    tcp_rndiss_next() - s->src.seqlo) == 0)
                                        ;
                                pf_change_a(&th->th_seq, &th->th_sum,
                                    htonl(s->src.seqlo + s->src.seqdiff), 0);
                                rewrite = 1;
                        } else
                                s->src.seqdiff = 0;
                        if (th->th_flags & TH_SYN) {
                                s->src.seqhi++;
                                s->src.wscale = pf_get_wscale(m, off,
                                    th->th_off, af);
                        }
                        s->src.max_win = MAX(ntohs(th->th_win), 1);
                        if (s->src.wscale & PF_WSCALE_MASK) {
                                /* Remove scale factor from initial window */
                                int win = s->src.max_win;
                                win += 1 << (s->src.wscale & PF_WSCALE_MASK);
                                s->src.max_win = (win - 1) >>
                                    (s->src.wscale & PF_WSCALE_MASK);
                        }
                        if (th->th_flags & TH_FIN)
                                s->src.seqhi++;
                        s->dst.seqhi = 1;
                        s->dst.max_win = 1;
                        s->src.state = TCPS_SYN_SENT;
                        s->dst.state = TCPS_CLOSED;
                        s->timeout = PFTM_TCP_FIRST_PACKET;
                        break;
                case IPPROTO_UDP:
                        s->src.state = PFUDPS_SINGLE;
                        s->dst.state = PFUDPS_NO_TRAFFIC;
                        s->timeout = PFTM_UDP_FIRST_PACKET;
                        break;
                case IPPROTO_ICMP:
#ifdef INET6
                case IPPROTO_ICMPV6:
#endif
                        s->timeout = PFTM_ICMP_FIRST_PACKET;
                        break;
                default:
                        s->src.state = PFOTHERS_SINGLE;
                        s->dst.state = PFOTHERS_NO_TRAFFIC;
                        s->timeout = PFTM_OTHER_FIRST_PACKET;
                }

                s->creation = time_second;
                s->expire = time_second;

                if (sn != NULL) {
                        s->src_node = sn;
                        s->src_node->states++;
                }
                if (nsn != NULL) {
                        PF_ACPY(&nsn->raddr, &pd->naddr, af);
                        s->nat_src_node = nsn;
                        s->nat_src_node->states++;
                }
                if (pd->proto == IPPROTO_TCP) {
                        if ((pd->flags & PFDESC_TCP_NORM) &&
                            pf_normalize_tcp_init(m, off, pd, th, &s->src,
                            &s->dst)) {
                                REASON_SET_NOPTR(&reason, PFRES_MEMORY);
                                pf_src_tree_remove_state(s);
                                STATE_DEC_COUNTERS(s);
                                pool_put(&pf_state_pl, s);
                                return (PF_DROP);
                        }
                        if ((pd->flags & PFDESC_TCP_NORM) && s->src.scrub &&
                            pf_normalize_tcp_stateful(m, off, pd, &reason,
                            th, s, &s->src, &s->dst, &rewrite)) {
                                /* This really shouldn't happen!!! */
                                DPFPRINTF(PF_DEBUG_URGENT,
                                    ("pf_normalize_tcp_stateful failed on "
                                    "first pkt"));
                                pf_normalize_tcp_cleanup(s);
                                pf_src_tree_remove_state(s);
                                STATE_DEC_COUNTERS(s);
                                pool_put(&pf_state_pl, s);
                                return (PF_DROP);
                        }
                }

                if ((sk = pf_alloc_state_key(s)) == NULL) {
                        REASON_SET_NOPTR(&reason, PFRES_MEMORY);
                        goto cleanup;
                }

                sk->proto = pd->proto;
                sk->direction = direction;
                sk->af = af;
                if (direction == PF_OUT) {
                        PF_ACPY(&sk->gwy.addr, saddr, af);
                        PF_ACPY(&sk->ext.addr, daddr, af);
                        switch (pd->proto) {
                        case IPPROTO_ICMP:
#ifdef INET6
                        case IPPROTO_ICMPV6:
#endif
                                sk->gwy.port = nport;
                                sk->ext.port = 0;
                                break;
                        default:
                                sk->gwy.port = sport;
                                sk->ext.port = dport;
                        }
                        if (nr != NULL) {
                                PF_ACPY(&sk->lan.addr, &pd->baddr, af);
                                sk->lan.port = bport;
                        } else {
                                PF_ACPY(&sk->lan.addr, &sk->gwy.addr, af);
                                sk->lan.port = sk->gwy.port;
                        }
                } else {
                        PF_ACPY(&sk->lan.addr, daddr, af);
                        PF_ACPY(&sk->ext.addr, saddr, af);
                        switch (pd->proto) {
                        case IPPROTO_ICMP:
#ifdef INET6
                        case IPPROTO_ICMPV6:
#endif
                                sk->lan.port = nport;
                                sk->ext.port = 0;
                                break;
                        default:
                                sk->lan.port = dport;
                                sk->ext.port = sport;
                        }
                        if (nr != NULL) {
                                PF_ACPY(&sk->gwy.addr, &pd->baddr, af);
                                sk->gwy.port = bport;
                        } else {
                                PF_ACPY(&sk->gwy.addr, &sk->lan.addr, af);
                                sk->gwy.port = sk->lan.port;
                        }
                }

                pf_set_rt_ifp(s, saddr);        /* needs s->state_key set */

                if (pf_insert_state(bound_iface(r, nr, kif), s)) {
                        if (pd->proto == IPPROTO_TCP)
                                pf_normalize_tcp_cleanup(s);
                        REASON_SET_NOPTR(&reason, PFRES_STATEINS);
                        pf_src_tree_remove_state(s);
                        STATE_DEC_COUNTERS(s);
                        pool_put(&pf_state_pl, s);
                        return (PF_DROP);
                } else
                        *sm = s;
                if (tag > 0) {
                        pf_tag_ref(tag);
                        s->tag = tag;
                }
                if (pd->proto == IPPROTO_TCP &&
                    (th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN &&
                    r->keep_state == PF_STATE_SYNPROXY) {
                        s->src.state = PF_TCPS_PROXY_SRC;
                        if (nr != NULL) {
                                if (direction == PF_OUT) {
                                        pf_change_ap(saddr, &th->th_sport,
                                            pd->ip_sum, &th->th_sum, &pd->baddr,
                                            bport, 0, af);
                                        sport = th->th_sport;
                                } else {
                                        pf_change_ap(daddr, &th->th_dport,
                                            pd->ip_sum, &th->th_sum, &pd->baddr,
                                            bport, 0, af);
                                        sport = th->th_dport;
                                }
                        }
                        s->src.seqhi = htonl(cprng_fast32());
                        /* Find mss option */
                        mss = pf_get_mss(m, off, th->th_off, af);
                        mss = pf_calc_mss(saddr, af, mss);
                        mss = pf_calc_mss(daddr, af, mss);
                        s->src.mss = mss;
                        pf_send_tcp(r, af, daddr, saddr, th->th_dport,
                            th->th_sport, s->src.seqhi, ntohl(th->th_seq) + 1,
                            TH_SYN|TH_ACK, 0, s->src.mss, 0, 1, 0, NULL, NULL);
                        REASON_SET_NOPTR(&reason, PFRES_SYNPROXY);
                        return (PF_SYNPROXY_DROP);
                }
        }

        /* copy back packet headers if we performed NAT operations */
        if (rewrite)
                m_copyback(m, off, hdrlen, pd->hdr.any);

        return (PF_PASS);
}

int
pf_test_fragment(struct pf_rule **rm, int direction, struct pfi_kif *kif,
    struct mbuf *m, void *h, struct pf_pdesc *pd, struct pf_rule **am,
    struct pf_ruleset **rsm)
{
        struct pf_rule          *r, *a = NULL;
        struct pf_ruleset       *ruleset = NULL;
        sa_family_t              af = pd->af;
        u_short                  reason;
        int                      tag = -1;
        int                      asd = 0;
        int                      match = 0;

        r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
        while (r != NULL) {
                r->evaluations++;
                if (pfi_kif_match(r->kif, kif) == r->ifnot)
                        r = r->skip[PF_SKIP_IFP].ptr;
                else if (r->direction && r->direction != direction)
                        r = r->skip[PF_SKIP_DIR].ptr;
                else if (r->af && r->af != af)
                        r = r->skip[PF_SKIP_AF].ptr;
                else if (r->proto && r->proto != pd->proto)
                        r = r->skip[PF_SKIP_PROTO].ptr;
                else if (PF_MISMATCHAW(&r->src.addr, pd->src, af,
                    r->src.neg, kif))
                        r = r->skip[PF_SKIP_SRC_ADDR].ptr;
                else if (PF_MISMATCHAW(&r->dst.addr, pd->dst, af,
                    r->dst.neg, NULL))
                        r = r->skip[PF_SKIP_DST_ADDR].ptr;
                else if (r->tos && !(r->tos == pd->tos))
                        r = TAILQ_NEXT(r, entries);
                else if (r->src.port_op || r->dst.port_op ||
                    r->flagset || r->type || r->code ||
                    r->os_fingerprint != PF_OSFP_ANY)
                        r = TAILQ_NEXT(r, entries);
                else if (r->prob && r->prob <= cprng_fast32())
                        r = TAILQ_NEXT(r, entries);
                else if (r->match_tag && !pf_match_tag(m, r, &tag))
                        r = TAILQ_NEXT(r, entries);
                else {
                        if (r->anchor == NULL) {
                                match = 1;
                                *rm = r;
                                *am = a;
                                *rsm = ruleset;
                                if ((*rm)->quick)
                                        break;
                                r = TAILQ_NEXT(r, entries);
                        } else
                                pf_step_into_anchor(&asd, &ruleset,
                                    PF_RULESET_FILTER, &r, &a, &match);
                }
                if (r == NULL && pf_step_out_of_anchor(&asd, &ruleset,
                    PF_RULESET_FILTER, &r, &a, &match))
                        break;
        }
        r = *rm;
        a = *am;
        ruleset = *rsm;

        REASON_SET_NOPTR(&reason, PFRES_MATCH);

        if (r->log)
                PFLOG_PACKET(kif, h, m, af, direction, reason, r, a, ruleset,
                    pd);

        if (r->action != PF_PASS)
                return (PF_DROP);

        if (pf_tag_packet(m, tag, -1)) {
                REASON_SET_NOPTR(&reason, PFRES_MEMORY);
                return (PF_DROP);
        }

        return (PF_PASS);
}

int
pf_test_state_tcp(struct pf_state **state, int direction, struct pfi_kif *kif,
    struct mbuf *m, int off, void *h, struct pf_pdesc *pd,
    u_short *reason)
{
        struct pf_state_key_cmp  key;
        struct tcphdr           *th = pd->hdr.tcp;
        u_int16_t                win = ntohs(th->th_win);
        u_int32_t                ack, end, seq, orig_seq;
        u_int8_t                 sws, dws;
        int                      ackskew;
        int                      copyback = 0;
        struct pf_state_peer    *src, *dst;

        key.af = pd->af;
        key.proto = IPPROTO_TCP;
        if (direction == PF_IN) {
                PF_ACPY(&key.ext.addr, pd->src, key.af);
                PF_ACPY(&key.gwy.addr, pd->dst, key.af);
                key.ext.port = th->th_sport;
                key.gwy.port = th->th_dport;
        } else {
                PF_ACPY(&key.lan.addr, pd->src, key.af);
                PF_ACPY(&key.ext.addr, pd->dst, key.af);
                key.lan.port = th->th_sport;
                key.ext.port = th->th_dport;
        }

        STATE_LOOKUP();

        if (direction == (*state)->state_key->direction) {
                src = &(*state)->src;
                dst = &(*state)->dst;
        } else {
                src = &(*state)->dst;
                dst = &(*state)->src;
        }

        if ((*state)->src.state == PF_TCPS_PROXY_SRC) {
                if (direction != (*state)->state_key->direction) {
                        REASON_SET(reason, PFRES_SYNPROXY);
                        return (PF_SYNPROXY_DROP);
                }
                if (th->th_flags & TH_SYN) {
                        if (ntohl(th->th_seq) != (*state)->src.seqlo) {
                                REASON_SET(reason, PFRES_SYNPROXY);
                                return (PF_DROP);
                        }
                        pf_send_tcp((*state)->rule.ptr, pd->af, pd->dst,
                            pd->src, th->th_dport, th->th_sport,
                            (*state)->src.seqhi, ntohl(th->th_seq) + 1,
                            TH_SYN|TH_ACK, 0, (*state)->src.mss, 0, 1,
                            0, NULL, NULL);
                        REASON_SET(reason, PFRES_SYNPROXY);
                        return (PF_SYNPROXY_DROP);
                } else if (!(th->th_flags & TH_ACK) ||
                    (ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
                    (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
                        REASON_SET(reason, PFRES_SYNPROXY);
                        return (PF_DROP);
                } else if ((*state)->src_node != NULL &&
                    pf_src_connlimit(state)) {
                        REASON_SET(reason, PFRES_SRCLIMIT);
                        return (PF_DROP);
                } else
                        (*state)->src.state = PF_TCPS_PROXY_DST;
        }
        if ((*state)->src.state == PF_TCPS_PROXY_DST) {
                struct pf_state_host *psrc, *pdst;

                if (direction == PF_OUT) {
                        psrc = &(*state)->state_key->gwy;
                        pdst = &(*state)->state_key->ext;
                } else {
                        psrc = &(*state)->state_key->ext;
                        pdst = &(*state)->state_key->lan;
                }
                if (direction == (*state)->state_key->direction) {
                        if (((th->th_flags & (TH_SYN|TH_ACK)) != TH_ACK) ||
                            (ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
                            (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
                                REASON_SET(reason, PFRES_SYNPROXY);
                                return (PF_DROP);
                        }
                        (*state)->src.max_win = MAX(ntohs(th->th_win), 1);
                        if ((*state)->dst.seqhi == 1)
                                (*state)->dst.seqhi = htonl(cprng_fast32());
                        pf_send_tcp((*state)->rule.ptr, pd->af, &psrc->addr,
                            &pdst->addr, psrc->port, pdst->port,
                            (*state)->dst.seqhi, 0, TH_SYN, 0,
                            (*state)->src.mss, 0, 0, (*state)->tag, NULL, NULL);
                        REASON_SET(reason, PFRES_SYNPROXY);
                        return (PF_SYNPROXY_DROP);
                } else if (((th->th_flags & (TH_SYN|TH_ACK)) !=
                    (TH_SYN|TH_ACK)) ||
                    (ntohl(th->th_ack) != (*state)->dst.seqhi + 1)) {
                        REASON_SET(reason, PFRES_SYNPROXY);
                        return (PF_DROP);
                } else {
                        (*state)->dst.max_win = MAX(ntohs(th->th_win), 1);
                        (*state)->dst.seqlo = ntohl(th->th_seq);
                        pf_send_tcp((*state)->rule.ptr, pd->af, pd->dst,
                            pd->src, th->th_dport, th->th_sport,
                            ntohl(th->th_ack), ntohl(th->th_seq) + 1,
                            TH_ACK, (*state)->src.max_win, 0, 0, 0,
                            (*state)->tag, NULL, NULL);
                        pf_send_tcp((*state)->rule.ptr, pd->af, &psrc->addr,
                            &pdst->addr, psrc->port, pdst->port,
                            (*state)->src.seqhi + 1, (*state)->src.seqlo + 1,
                            TH_ACK, (*state)->dst.max_win, 0, 0, 1,
                            0, NULL, NULL);
                        (*state)->src.seqdiff = (*state)->dst.seqhi -
                            (*state)->src.seqlo;
                        (*state)->dst.seqdiff = (*state)->src.seqhi -
                            (*state)->dst.seqlo;
                        (*state)->src.seqhi = (*state)->src.seqlo +
                            (*state)->dst.max_win;
                        (*state)->dst.seqhi = (*state)->dst.seqlo +
                            (*state)->src.max_win;
                        (*state)->src.wscale = (*state)->dst.wscale = 0;
                        (*state)->src.state = (*state)->dst.state =
                            TCPS_ESTABLISHED;
                        REASON_SET(reason, PFRES_SYNPROXY);
                        return (PF_SYNPROXY_DROP);
                }
        }

        if (src->wscale && dst->wscale && !(th->th_flags & TH_SYN)) {
                sws = src->wscale & PF_WSCALE_MASK;
                dws = dst->wscale & PF_WSCALE_MASK;
        } else
                sws = dws = 0;

        /*
         * Sequence tracking algorithm from Guido van Rooij's paper:
         *   http://www.madison-gurkha.com/publications/tcp_filtering/
         *      tcp_filtering.ps
         */

        orig_seq = seq = ntohl(th->th_seq);
        if (src->seqlo == 0) {
                /* First packet from this end. Set its state */

                if ((pd->flags & PFDESC_TCP_NORM || dst->scrub) &&
                    src->scrub == NULL) {
                        if (pf_normalize_tcp_init(m, off, pd, th, src, dst)) {
                                REASON_SET(reason, PFRES_MEMORY);
                                return (PF_DROP);
                        }
                }

                /* Deferred generation of sequence number modulator */
                if (dst->seqdiff && !src->seqdiff) {
                        while ((src->seqdiff = tcp_rndiss_next() - seq) == 0)
                                ;
                        ack = ntohl(th->th_ack) - dst->seqdiff;
                        pf_change_a(&th->th_seq, &th->th_sum, htonl(seq +
                            src->seqdiff), 0);
                        pf_change_a(&th->th_ack, &th->th_sum, htonl(ack), 0);
                        copyback = 1;
                } else {
                        ack = ntohl(th->th_ack);
                }

                end = seq + pd->p_len;
                if (th->th_flags & TH_SYN) {
                        end++;
                        if (dst->wscale & PF_WSCALE_FLAG) {
                                src->wscale = pf_get_wscale(m, off, th->th_off,
                                    pd->af);
                                if (src->wscale & PF_WSCALE_FLAG) {
                                        /* Remove scale factor from initial
                                         * window */
                                        sws = src->wscale & PF_WSCALE_MASK;
                                        win = ((u_int32_t)win + (1 << sws) - 1)
                                            >> sws;
                                        dws = dst->wscale & PF_WSCALE_MASK;
                                } else {
                                        /* fixup other window */
                                        dst->max_win <<= dst->wscale &
                                            PF_WSCALE_MASK;
                                        /* in case of a retrans SYN|ACK */
                                        dst->wscale = 0;
                                }
                        }
                }
                if (th->th_flags & TH_FIN)
                        end++;

                src->seqlo = seq;
                if (src->state < TCPS_SYN_SENT)
                        src->state = TCPS_SYN_SENT;

                /*
                 * May need to slide the window (seqhi may have been set by
                 * the crappy stack check or if we picked up the connection
                 * after establishment)
                 */
                if (src->seqhi == 1 ||
                    SEQ_GEQ(end + MAX(1, dst->max_win << dws), src->seqhi))
                        src->seqhi = end + MAX(1, dst->max_win << dws);
                if (win > src->max_win)
                        src->max_win = win;

        } else {
                ack = ntohl(th->th_ack) - dst->seqdiff;
                if (src->seqdiff) {
                        /* Modulate sequence numbers */
                        pf_change_a(&th->th_seq, &th->th_sum, htonl(seq +
                            src->seqdiff), 0);
                        pf_change_a(&th->th_ack, &th->th_sum, htonl(ack), 0);
                        copyback = 1;
                }
                end = seq + pd->p_len;
                if (th->th_flags & TH_SYN)
                        end++;
                if (th->th_flags & TH_FIN)
                        end++;
        }

        if ((th->th_flags & TH_ACK) == 0) {
                /* Let it pass through the ack skew check */
                ack = dst->seqlo;
        } else if ((ack == 0 &&
            (th->th_flags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) ||
            /* broken tcp stacks do not set ack */
            (dst->state < TCPS_SYN_SENT)) {
                /*
                 * Many stacks (ours included) will set the ACK number in an
                 * FIN|ACK if the SYN times out -- no sequence to ACK.
                 */
                ack = dst->seqlo;
        }

        if (seq == end) {
                /* Ease sequencing restrictions on no data packets */
                seq = src->seqlo;
                end = seq;
        }

        ackskew = dst->seqlo - ack;


        /*
         * Need to demodulate the sequence numbers in any TCP SACK options
         * (Selective ACK). We could optionally validate the SACK values
         * against the current ACK window, either forwards or backwards, but
         * I'm not confident that SACK has been implemented properly
         * everywhere. It wouldn't surprise me if several stacks accidently
         * SACK too far backwards of previously ACKed data. There really aren't
         * any security implications of bad SACKing unless the target stack
         * doesn't validate the option length correctly. Someone trying to
         * spoof into a TCP connection won't bother blindly sending SACK
         * options anyway.
         */
        if (dst->seqdiff && (th->th_off << 2) > sizeof(struct tcphdr)) {
                if (pf_modulate_sack(m, off, pd, th, dst))
                        copyback = 1;
        }


#define MAXACKWINDOW (0xffff + 1500)    /* 1500 is an arbitrary fudge factor */
        if (SEQ_GEQ(src->seqhi, end) &&
            /* Last octet inside other's window space */
            SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) &&
            /* Retrans: not more than one window back */
            (ackskew >= -MAXACKWINDOW) &&
            /* Acking not more than one reassembled fragment backwards */
            (ackskew <= (MAXACKWINDOW << sws)) &&
            /* Acking not more than one window forward */
            ((th->th_flags & TH_RST) == 0 || orig_seq == src->seqlo ||
            (orig_seq == src->seqlo + 1) || (pd->flags & PFDESC_IP_REAS) == 0)) {
            /* Require an exact/+1 sequence match on resets when possible */

                if (dst->scrub || src->scrub) {
                        if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
                            *state, src, dst, &copyback))
                                return (PF_DROP);
                }

                /* update max window */
                if (src->max_win < win)
                        src->max_win = win;
                /* synchronize sequencing */
                if (SEQ_GT(end, src->seqlo))
                        src->seqlo = end;
                /* slide the window of what the other end can send */
                if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
                        dst->seqhi = ack + MAX((win << sws), 1);


                /* update states */
                if (th->th_flags & TH_SYN)
                        if (src->state < TCPS_SYN_SENT)
                                src->state = TCPS_SYN_SENT;
                if (th->th_flags & TH_FIN)
                        if (src->state < TCPS_CLOSING)
                                src->state = TCPS_CLOSING;
                if (th->th_flags & TH_ACK) {
                        if (dst->state == TCPS_SYN_SENT) {
                                dst->state = TCPS_ESTABLISHED;
                                if (src->state == TCPS_ESTABLISHED &&
                                    (*state)->src_node != NULL &&
                                    pf_src_connlimit(state)) {
                                        REASON_SET(reason, PFRES_SRCLIMIT);
                                        return (PF_DROP);
                                }
                        } else if (dst->state == TCPS_CLOSING)
                                dst->state = TCPS_FIN_WAIT_2;
                }
                if (th->th_flags & TH_RST)
                        src->state = dst->state = TCPS_TIME_WAIT;

                /* update expire time */
                (*state)->expire = time_second;
                if (src->state >= TCPS_FIN_WAIT_2 &&
                    dst->state >= TCPS_FIN_WAIT_2)
                        (*state)->timeout = PFTM_TCP_CLOSED;
                else if (src->state >= TCPS_CLOSING &&
                    dst->state >= TCPS_CLOSING)
                        (*state)->timeout = PFTM_TCP_FIN_WAIT;
                else if (src->state < TCPS_ESTABLISHED ||
                    dst->state < TCPS_ESTABLISHED)
                        (*state)->timeout = PFTM_TCP_OPENING;
                else if (src->state >= TCPS_CLOSING ||
                    dst->state >= TCPS_CLOSING)
                        (*state)->timeout = PFTM_TCP_CLOSING;
                else
                        (*state)->timeout = PFTM_TCP_ESTABLISHED;

                /* Fall through to PASS packet */

        } else if ((dst->state < TCPS_SYN_SENT ||
                dst->state >= TCPS_FIN_WAIT_2 ||
                src->state >= TCPS_FIN_WAIT_2) &&
            SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) &&
            /* Within a window forward of the originating packet */
            SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW)) {
            /* Within a window backward of the originating packet */

                /*
                 * This currently handles three situations:
                 *  1) Stupid stacks will shotgun SYNs before their peer
                 *     replies.
                 *  2) When PF catches an already established stream (the
                 *     firewall rebooted, the state table was flushed, routes
                 *     changed...)
                 *  3) Packets get funky immediately after the connection
                 *     closes (this should catch Solaris spurious ACK|FINs
                 *     that web servers like to spew after a close)
                 *
                 * This must be a little more careful than the above code
                 * since packet floods will also be caught here. We don't
                 * update the TTL here to mitigate the damage of a packet
                 * flood and so the same code can handle awkward establishment
                 * and a loosened connection close.
                 * In the establishment case, a correct peer response will
                 * validate the connection, go through the normal state code
                 * and keep updating the state TTL.
                 */

                if (pf_status.debug >= PF_DEBUG_MISC) {
                        printf("pf: loose state match: ");
                        pf_print_state(*state);
                        pf_print_flags(th->th_flags);
                        printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
                            "pkts=%llu:%llu\n", seq, orig_seq, ack, pd->p_len,
                            ackskew,
                            (unsigned long long int)(*state)->packets[0],
                            (unsigned long long int)(*state)->packets[1]);
                }

                if (dst->scrub || src->scrub) {
                        if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
                            *state, src, dst, &copyback))
                                return (PF_DROP);
                }

                /* update max window */
                if (src->max_win < win)
                        src->max_win = win;
                /* synchronize sequencing */
                if (SEQ_GT(end, src->seqlo))
                        src->seqlo = end;
                /* slide the window of what the other end can send */
                if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
                        dst->seqhi = ack + MAX((win << sws), 1);

                /*
                 * Cannot set dst->seqhi here since this could be a shotgunned
                 * SYN and not an already established connection.
                 */

                if (th->th_flags & TH_FIN)
                        if (src->state < TCPS_CLOSING)
                                src->state = TCPS_CLOSING;
                if (th->th_flags & TH_RST)
                        src->state = dst->state = TCPS_TIME_WAIT;

                /* Fall through to PASS packet */

        } else {
                if ((*state)->dst.state == TCPS_SYN_SENT &&
                    (*state)->src.state == TCPS_SYN_SENT) {
                        /* Send RST for state mismatches during handshake */
                        if (!(th->th_flags & TH_RST))
                                pf_send_tcp((*state)->rule.ptr, pd->af,
                                    pd->dst, pd->src, th->th_dport,
                                    th->th_sport, ntohl(th->th_ack), 0,
                                    TH_RST, 0, 0,
                                    (*state)->rule.ptr->return_ttl, 1, 0,
                                    pd->eh, kif->pfik_ifp);
                        src->seqlo = 0;
                        src->seqhi = 1;
                        src->max_win = 1;
                } else if (pf_status.debug >= PF_DEBUG_MISC) {
                        printf("pf: BAD state: ");
                        pf_print_state(*state);
                        pf_print_flags(th->th_flags);
                        printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
                            "pkts=%llu:%llu dir=%s,%s\n",
                            seq, orig_seq, ack, pd->p_len, ackskew,
                            (unsigned long long int)(*state)->packets[0],
                            (unsigned long long int)(*state)->packets[1],
                            direction == PF_IN ? "in" : "out",
                            direction == (*state)->state_key->direction ?
                                "fwd" : "rev");
                        printf("pf: State failure on: %c %c %c %c | %c %c\n",
                            SEQ_GEQ(src->seqhi, end) ? ' ' : '1',
                            SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) ?
                            ' ': '2',
                            (ackskew >= -MAXACKWINDOW) ? ' ' : '3',
                            (ackskew <= (MAXACKWINDOW << sws)) ? ' ' : '4',
                            SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) ?' ' :'5',
                            SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW) ?' ' :'6');
                }
                REASON_SET(reason, PFRES_BADSTATE);
                return (PF_DROP);
        }

        /* Any packets which have gotten here are to be passed */

        /* translate source/destination address, if necessary */
        if (STATE_TRANSLATE((*state)->state_key)) {
                if (direction == PF_OUT)
                        pf_change_ap(pd->src, &th->th_sport, pd->ip_sum,
                            &th->th_sum, &(*state)->state_key->gwy.addr,
                            (*state)->state_key->gwy.port, 0, pd->af);
                else
                        pf_change_ap(pd->dst, &th->th_dport, pd->ip_sum,
                            &th->th_sum, &(*state)->state_key->lan.addr,
                            (*state)->state_key->lan.port, 0, pd->af);
                m_copyback(m, off, sizeof(*th), th);
        } else if (copyback) {
                /* Copyback sequence modulation or stateful scrub changes */
                m_copyback(m, off, sizeof(*th), th);
        }

        return (PF_PASS);
}

int
pf_test_state_udp(struct pf_state **state, int direction, struct pfi_kif *kif,
    struct mbuf *m, int off, void *h, struct pf_pdesc *pd)
{
        struct pf_state_peer    *src, *dst;
        struct pf_state_key_cmp  key;
        struct udphdr           *uh = pd->hdr.udp;

        key.af = pd->af;
        key.proto = IPPROTO_UDP;
        if (direction == PF_IN) {
                PF_ACPY(&key.ext.addr, pd->src, key.af);
                PF_ACPY(&key.gwy.addr, pd->dst, key.af);
                key.ext.port = uh->uh_sport;
                key.gwy.port = uh->uh_dport;
        } else {
                PF_ACPY(&key.lan.addr, pd->src, key.af);
                PF_ACPY(&key.ext.addr, pd->dst, key.af);
                key.lan.port = uh->uh_sport;
                key.ext.port = uh->uh_dport;
        }

        STATE_LOOKUP();

        if (direction == (*state)->state_key->direction) {
                src = &(*state)->src;
                dst = &(*state)->dst;
        } else {
                src = &(*state)->dst;
                dst = &(*state)->src;
        }

        /* update states */
        if (src->state < PFUDPS_SINGLE)
                src->state = PFUDPS_SINGLE;
        if (dst->state == PFUDPS_SINGLE)
                dst->state = PFUDPS_MULTIPLE;

        /* update expire time */
        (*state)->expire = time_second;
        if (src->state == PFUDPS_MULTIPLE && dst->state == PFUDPS_MULTIPLE)
                (*state)->timeout = PFTM_UDP_MULTIPLE;
        else
                (*state)->timeout = PFTM_UDP_SINGLE;

        /* translate source/destination address, if necessary */
        if (STATE_TRANSLATE((*state)->state_key)) {
                if (direction == PF_OUT)
                        pf_change_ap(pd->src, &uh->uh_sport, pd->ip_sum,
                            &uh->uh_sum, &(*state)->state_key->gwy.addr,
                            (*state)->state_key->gwy.port, 1, pd->af);
                else
                        pf_change_ap(pd->dst, &uh->uh_dport, pd->ip_sum,
                            &uh->uh_sum, &(*state)->state_key->lan.addr,
                            (*state)->state_key->lan.port, 1, pd->af);
                m_copyback(m, off, sizeof(*uh), uh);
        }

        return (PF_PASS);
}

int
pf_test_state_icmp(struct pf_state **state, int direction, struct pfi_kif *kif,
    struct mbuf *m, int off, void *h, struct pf_pdesc *pd,
    u_short *reason)
{
        struct pf_addr  *saddr = pd->src, *daddr = pd->dst;
        u_int16_t        icmpid = 0, *icmpsum;
        u_int8_t         icmptype;
        int              state_icmp = 0;
        struct pf_state_key_cmp key;

        icmpsum = NULL; /* XXXGCC -Wuninitialized m68k */
        icmptype = 0;   /* XXXGCC -Wuninitialized m68k */

        switch (pd->proto) {
#ifdef INET
        case IPPROTO_ICMP:
                icmptype = pd->hdr.icmp->icmp_type;
                icmpid = pd->hdr.icmp->icmp_id;
                icmpsum = &pd->hdr.icmp->icmp_cksum;

                if (icmptype == ICMP_UNREACH ||
                    icmptype == ICMP_SOURCEQUENCH ||
                    icmptype == ICMP_REDIRECT ||
                    icmptype == ICMP_TIMXCEED ||
                    icmptype == ICMP_PARAMPROB)
                        state_icmp++;
                break;
#endif /* INET */
#ifdef INET6
        case IPPROTO_ICMPV6:
                icmptype = pd->hdr.icmp6->icmp6_type;
                icmpid = pd->hdr.icmp6->icmp6_id;
                icmpsum = &pd->hdr.icmp6->icmp6_cksum;

                if (icmptype == ICMP6_DST_UNREACH ||
                    icmptype == ICMP6_PACKET_TOO_BIG ||
                    icmptype == ICMP6_TIME_EXCEEDED ||
                    icmptype == ICMP6_PARAM_PROB)
                        state_icmp++;
                break;
#endif /* INET6 */
        }

        if (!state_icmp) {

                /*
                 * ICMP query/reply message not related to a TCP/UDP packet.
                 * Search for an ICMP state.
                 */
                key.af = pd->af;
                key.proto = pd->proto;
                if (direction == PF_IN) {
                        PF_ACPY(&key.ext.addr, pd->src, key.af);
                        PF_ACPY(&key.gwy.addr, pd->dst, key.af);
                        key.ext.port = 0;
                        key.gwy.port = icmpid;
                } else {
                        PF_ACPY(&key.lan.addr, pd->src, key.af);
                        PF_ACPY(&key.ext.addr, pd->dst, key.af);
                        key.lan.port = icmpid;
                        key.ext.port = 0;
                }

                STATE_LOOKUP();

                (*state)->expire = time_second;
                (*state)->timeout = PFTM_ICMP_ERROR_REPLY;

                /* translate source/destination address, if necessary */
                if (STATE_TRANSLATE((*state)->state_key)) {
                        if (direction == PF_OUT) {
                                switch (pd->af) {
#ifdef INET
                                case AF_INET:
                                        pf_change_a(&saddr->v4.s_addr,
                                            pd->ip_sum,
                                            (*state)->state_key->gwy.addr.v4.s_addr, 0);
                                        pd->hdr.icmp->icmp_cksum =
                                            pf_cksum_fixup(
                                            pd->hdr.icmp->icmp_cksum, icmpid,
                                            (*state)->state_key->gwy.port, 0);
                                        pd->hdr.icmp->icmp_id =
                                            (*state)->state_key->gwy.port;
                                        m_copyback(m, off, ICMP_MINLEN,
                                            pd->hdr.icmp);
                                        break;
#endif /* INET */
#ifdef INET6
                                case AF_INET6:
                                        pf_change_a6(saddr,
                                            &pd->hdr.icmp6->icmp6_cksum,
                                            &(*state)->state_key->gwy.addr, 0);
                                        m_copyback(m, off,
                                            sizeof(struct icmp6_hdr),
                                            pd->hdr.icmp6);
                                        break;
#endif /* INET6 */
                                }
                        } else {
                                switch (pd->af) {
#ifdef INET
                                case AF_INET:
                                        pf_change_a(&daddr->v4.s_addr,
                                            pd->ip_sum,
                                            (*state)->state_key->lan.addr.v4.s_addr, 0);
                                        pd->hdr.icmp->icmp_cksum =
                                            pf_cksum_fixup(
                                            pd->hdr.icmp->icmp_cksum, icmpid,
                                            (*state)->state_key->lan.port, 0);
                                        pd->hdr.icmp->icmp_id =
                                            (*state)->state_key->lan.port;
                                        m_copyback(m, off, ICMP_MINLEN,
                                            pd->hdr.icmp);
                                        break;
#endif /* INET */
#ifdef INET6
                                case AF_INET6:
                                        pf_change_a6(daddr,
                                            &pd->hdr.icmp6->icmp6_cksum,
                                            &(*state)->state_key->lan.addr, 0);
                                        m_copyback(m, off,
                                            sizeof(struct icmp6_hdr),
                                            pd->hdr.icmp6);
                                        break;
#endif /* INET6 */
                                }
                        }
                }

                return (PF_PASS);

        } else {
                /*
                 * ICMP error message in response to a TCP/UDP packet.
                 * Extract the inner TCP/UDP header and search for that state.
                 */

                struct pf_pdesc pd2;
#ifdef INET
                struct ip       h2;
#endif /* INET */
#ifdef INET6
                struct ip6_hdr  h2_6;
                int             terminal = 0;
#endif /* INET6 */
                int             ipoff2 = 0;
                int             off2 = 0;

                memset(&pd2, 0, sizeof pd2);    /* XXX gcc */

                pd2.af = pd->af;
                switch (pd->af) {
#ifdef INET
                case AF_INET:
                        /* offset of h2 in mbuf chain */
                        ipoff2 = off + ICMP_MINLEN;

                        if (!pf_pull_hdr(m, ipoff2, &h2, sizeof(h2),
                            NULL, reason, pd2.af)) {
                                DPFPRINTF(PF_DEBUG_MISC,
                                    ("pf: ICMP error message too short "
                                    "(ip)\n"));
                                return (PF_DROP);
                        }
                        /*
                         * ICMP error messages don't refer to non-first
                         * fragments
                         */
                        if (h2.ip_off & htons(IP_OFFMASK)) {
                                REASON_SET(reason, PFRES_FRAG);
                                return (PF_DROP);
                        }

                        /* offset of protocol header that follows h2 */
                        off2 = ipoff2 + (h2.ip_hl << 2);

                        pd2.proto = h2.ip_p;
                        pd2.src = (struct pf_addr *)&h2.ip_src;
                        pd2.dst = (struct pf_addr *)&h2.ip_dst;
                        pd2.ip_sum = &h2.ip_sum;
                        break;
#endif /* INET */
#ifdef INET6
                case AF_INET6:
                        ipoff2 = off + sizeof(struct icmp6_hdr);

                        if (!pf_pull_hdr(m, ipoff2, &h2_6, sizeof(h2_6),
                            NULL, reason, pd2.af)) {
                                DPFPRINTF(PF_DEBUG_MISC,
                                    ("pf: ICMP error message too short "
                                    "(ip6)\n"));
                                return (PF_DROP);
                        }
                        pd2.proto = h2_6.ip6_nxt;
                        pd2.src = (struct pf_addr *)&h2_6.ip6_src;
                        pd2.dst = (struct pf_addr *)&h2_6.ip6_dst;
                        pd2.ip_sum = NULL;
                        off2 = ipoff2 + sizeof(h2_6);
                        do {
                                switch (pd2.proto) {
                                case IPPROTO_FRAGMENT:
                                        /*
                                         * ICMPv6 error messages for
                                         * non-first fragments
                                         */
                                        REASON_SET(reason, PFRES_FRAG);
                                        return (PF_DROP);
                                case IPPROTO_AH:
                                case IPPROTO_HOPOPTS:
                                case IPPROTO_ROUTING:
                                case IPPROTO_DSTOPTS: {
                                        /* get next header and header length */
                                        struct ip6_ext opt6;

                                        if (!pf_pull_hdr(m, off2, &opt6,
                                            sizeof(opt6), NULL, reason,
                                            pd2.af)) {
                                                DPFPRINTF(PF_DEBUG_MISC,
                                                    ("pf: ICMPv6 short opt\n"));
                                                return (PF_DROP);
                                        }
                                        if (pd2.proto == IPPROTO_AH)
                                                off2 += (opt6.ip6e_len + 2) * 4;
                                        else
                                                off2 += (opt6.ip6e_len + 1) * 8;
                                        pd2.proto = opt6.ip6e_nxt;
                                        /* goto the next header */
                                        break;
                                }
                                default:
                                        terminal++;
                                        break;
                                }
                        } while (!terminal);
                        break;
#endif /* INET6 */
                }

                switch (pd2.proto) {
                case IPPROTO_TCP: {
                        struct tcphdr            th;
                        u_int32_t                seq;
                        struct pf_state_peer    *src, *dst;
                        u_int8_t                 dws;
                        int                      copyback = 0;

                        /*
                         * Only the first 8 bytes of the TCP header can be
                         * expected. Don't access any TCP header fields after
                         * th_seq, an ackskew test is not possible.
                         */
                        if (!pf_pull_hdr(m, off2, &th, 8, NULL, reason,
                            pd2.af)) {
                                DPFPRINTF(PF_DEBUG_MISC,
                                    ("pf: ICMP error message too short "
                                    "(tcp)\n"));
                                return (PF_DROP);
                        }

                        key.af = pd2.af;
                        key.proto = IPPROTO_TCP;
                        if (direction == PF_IN) {
                                PF_ACPY(&key.ext.addr, pd2.dst, key.af);
                                PF_ACPY(&key.gwy.addr, pd2.src, key.af);
                                key.ext.port = th.th_dport;
                                key.gwy.port = th.th_sport;
                        } else {
                                PF_ACPY(&key.lan.addr, pd2.dst, key.af);
                                PF_ACPY(&key.ext.addr, pd2.src, key.af);
                                key.lan.port = th.th_dport;
                                key.ext.port = th.th_sport;
                        }

                        STATE_LOOKUP();

                        if (direction == (*state)->state_key->direction) {
                                src = &(*state)->dst;
                                dst = &(*state)->src;
                        } else {
                                src = &(*state)->src;
                                dst = &(*state)->dst;
                        }

                        if (src->wscale && dst->wscale)
                                dws = dst->wscale & PF_WSCALE_MASK;
                        else
                                dws = 0;

                        /* Demodulate sequence number */
                        seq = ntohl(th.th_seq) - src->seqdiff;
                        if (src->seqdiff) {
                                pf_change_a(&th.th_seq, icmpsum,
                                    htonl(seq), 0);
                                copyback = 1;
                        }

                        if (!SEQ_GEQ(src->seqhi, seq) ||
                            !SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws))) {
                                if (pf_status.debug >= PF_DEBUG_MISC) {
                                        printf("pf: BAD ICMP %d:%d ",
                                            icmptype, pd->hdr.icmp->icmp_code);
                                        pf_print_host(pd->src, 0, pd->af);
                                        printf(" -> ");
                                        pf_print_host(pd->dst, 0, pd->af);
                                        printf(" state: ");
                                        pf_print_state(*state);
                                        printf(" seq=%u\n", seq);
                                }
                                REASON_SET(reason, PFRES_BADSTATE);
                                return (PF_DROP);
                        }

                        if (STATE_TRANSLATE((*state)->state_key)) {
                                if (direction == PF_IN) {
                                        pf_change_icmp(pd2.src, &th.th_sport,
                                            daddr, &(*state)->state_key->lan.addr,
                                            (*state)->state_key->lan.port, NULL,
                                            pd2.ip_sum, icmpsum,
                                            pd->ip_sum, 0, pd2.af);
                                } else {
                                        pf_change_icmp(pd2.dst, &th.th_dport,
                                            saddr, &(*state)->state_key->gwy.addr,
                                            (*state)->state_key->gwy.port, NULL,
                                            pd2.ip_sum, icmpsum,
                                            pd->ip_sum, 0, pd2.af);
                                }
                                copyback = 1;
                        }

                        if (copyback) {
                                switch (pd2.af) {
#ifdef INET
                                case AF_INET:
                                        m_copyback(m, off, ICMP_MINLEN,
                                            pd->hdr.icmp);
                                        m_copyback(m, ipoff2, sizeof(h2),
                                            &h2);
                                        break;
#endif /* INET */
#ifdef INET6
                                case AF_INET6:
                                        m_copyback(m, off,
                                            sizeof(struct icmp6_hdr),
                                            pd->hdr.icmp6);
                                        m_copyback(m, ipoff2, sizeof(h2_6),
                                            &h2_6);
                                        break;
#endif /* INET6 */
                                }
                                m_copyback(m, off2, 8, &th);
                        }

                        return (PF_PASS);
                        break;
                }
                case IPPROTO_UDP: {
                        struct udphdr           uh;

                        if (!pf_pull_hdr(m, off2, &uh, sizeof(uh),
                            NULL, reason, pd2.af)) {
                                DPFPRINTF(PF_DEBUG_MISC,
                                    ("pf: ICMP error message too short "
                                    "(udp)\n"));
                                return (PF_DROP);
                        }

                        key.af = pd2.af;
                        key.proto = IPPROTO_UDP;
                        if (direction == PF_IN) {
                                PF_ACPY(&key.ext.addr, pd2.dst, key.af);
                                PF_ACPY(&key.gwy.addr, pd2.src, key.af);
                                key.ext.port = uh.uh_dport;
                                key.gwy.port = uh.uh_sport;
                        } else {
                                PF_ACPY(&key.lan.addr, pd2.dst, key.af);
                                PF_ACPY(&key.ext.addr, pd2.src, key.af);
                                key.lan.port = uh.uh_dport;
                                key.ext.port = uh.uh_sport;
                        }

                        STATE_LOOKUP();

                        if (STATE_TRANSLATE((*state)->state_key)) {
                                if (direction == PF_IN) {
                                        pf_change_icmp(pd2.src, &uh.uh_sport,
                                            daddr,
                                            &(*state)->state_key->lan.addr,
                                            (*state)->state_key->lan.port,
                                            &uh.uh_sum,
                                            pd2.ip_sum, icmpsum,
                                            pd->ip_sum, 1, pd2.af);
                                } else {
                                        pf_change_icmp(pd2.dst, &uh.uh_dport,
                                            saddr,
                                            &(*state)->state_key->gwy.addr,
                                            (*state)->state_key->gwy.port, &uh.uh_sum,
                                            pd2.ip_sum, icmpsum,
                                            pd->ip_sum, 1, pd2.af);
                                }
                                switch (pd2.af) {
#ifdef INET
                                case AF_INET:
                                        m_copyback(m, off, ICMP_MINLEN,
                                            pd->hdr.icmp);
                                        m_copyback(m, ipoff2, sizeof(h2), &h2);
                                        break;
#endif /* INET */
#ifdef INET6
                                case AF_INET6:
                                        m_copyback(m, off,
                                            sizeof(struct icmp6_hdr),
                                            pd->hdr.icmp6);
                                        m_copyback(m, ipoff2, sizeof(h2_6),
                                            &h2_6);
                                        break;
#endif /* INET6 */
                                }
                                m_copyback(m, off2, sizeof(uh), &uh);
                        }

                        return (PF_PASS);
                        break;
                }
#ifdef INET
                case IPPROTO_ICMP: {
                        struct icmp             iih;

                        if (!pf_pull_hdr(m, off2, &iih, ICMP_MINLEN,
                            NULL, reason, pd2.af)) {
                                DPFPRINTF(PF_DEBUG_MISC,
                                    ("pf: ICMP error message too short i"
                                    "(icmp)\n"));
                                return (PF_DROP);
                        }

                        key.af = pd2.af;
                        key.proto = IPPROTO_ICMP;
                        if (direction == PF_IN) {
                                PF_ACPY(&key.ext.addr, pd2.dst, key.af);
                                PF_ACPY(&key.gwy.addr, pd2.src, key.af);
                                key.ext.port = 0;
                                key.gwy.port = iih.icmp_id;
                        } else {
                                PF_ACPY(&key.lan.addr, pd2.dst, key.af);
                                PF_ACPY(&key.ext.addr, pd2.src, key.af);
                                key.lan.port = iih.icmp_id;
                                key.ext.port = 0;
                        }

                        STATE_LOOKUP();

                        if (STATE_TRANSLATE((*state)->state_key)) {
                                if (direction == PF_IN) {
                                        pf_change_icmp(pd2.src, &iih.icmp_id,
                                            daddr,
                                            &(*state)->state_key->lan.addr,
                                            (*state)->state_key->lan.port, NULL,
                                            pd2.ip_sum, icmpsum,
                                            pd->ip_sum, 0, AF_INET);
                                } else {
                                        pf_change_icmp(pd2.dst, &iih.icmp_id,
                                            saddr,
                                            &(*state)->state_key->gwy.addr,
                                            (*state)->state_key->gwy.port, NULL,
                                            pd2.ip_sum, icmpsum,
                                            pd->ip_sum, 0, AF_INET);
                                }
                                m_copyback(m, off, ICMP_MINLEN, pd->hdr.icmp);
                                m_copyback(m, ipoff2, sizeof(h2), &h2);
                                m_copyback(m, off2, ICMP_MINLEN, &iih);
                        }

                        return (PF_PASS);
                        break;
                }
#endif /* INET */
#ifdef INET6
                case IPPROTO_ICMPV6: {
                        struct icmp6_hdr        iih;

                        if (!pf_pull_hdr(m, off2, &iih,
                            sizeof(struct icmp6_hdr), NULL, reason, pd2.af)) {
                                DPFPRINTF(PF_DEBUG_MISC,
                                    ("pf: ICMP error message too short "
                                    "(icmp6)\n"));
                                return (PF_DROP);
                        }

                        key.af = pd2.af;
                        key.proto = IPPROTO_ICMPV6;
                        if (direction == PF_IN) {
                                PF_ACPY(&key.ext.addr, pd2.dst, key.af);
                                PF_ACPY(&key.gwy.addr, pd2.src, key.af);
                                key.ext.port = 0;
                                key.gwy.port = iih.icmp6_id;
                        } else {
                                PF_ACPY(&key.lan.addr, pd2.dst, key.af);
                                PF_ACPY(&key.ext.addr, pd2.src, key.af);
                                key.lan.port = iih.icmp6_id;
                                key.ext.port = 0;
                        }

                        STATE_LOOKUP();

                        if (STATE_TRANSLATE((*state)->state_key)) {
                                if (direction == PF_IN) {
                                        pf_change_icmp(pd2.src, &iih.icmp6_id,
                                            daddr,
                                            &(*state)->state_key->lan.addr,
                                            (*state)->state_key->lan.port, NULL,
                                            pd2.ip_sum, icmpsum,
                                            pd->ip_sum, 0, AF_INET6);
                                } else {
                                        pf_change_icmp(pd2.dst, &iih.icmp6_id,
                                            saddr, &(*state)->state_key->gwy.addr,
                                            (*state)->state_key->gwy.port, NULL,
                                            pd2.ip_sum, icmpsum,
                                            pd->ip_sum, 0, AF_INET6);
                                }
                                m_copyback(m, off, sizeof(struct icmp6_hdr),
                                    pd->hdr.icmp6);
                                m_copyback(m, ipoff2, sizeof(h2_6), &h2_6);
                                m_copyback(m, off2, sizeof(struct icmp6_hdr),
                                    &iih);
                        }

                        return (PF_PASS);
                        break;
                }
#endif /* INET6 */
                default: {
                        key.af = pd2.af;
                        key.proto = pd2.proto;
                        if (direction == PF_IN) {
                                PF_ACPY(&key.ext.addr, pd2.dst, key.af);
                                PF_ACPY(&key.gwy.addr, pd2.src, key.af);
                                key.ext.port = 0;
                                key.gwy.port = 0;
                        } else {
                                PF_ACPY(&key.lan.addr, pd2.dst, key.af);
                                PF_ACPY(&key.ext.addr, pd2.src, key.af);
                                key.lan.port = 0;
                                key.ext.port = 0;
                        }

                        STATE_LOOKUP();

                        if (STATE_TRANSLATE((*state)->state_key)) {
                                if (direction == PF_IN) {
                                        pf_change_icmp(pd2.src, NULL,
                                            daddr,
                                            &(*state)->state_key->lan.addr,
                                            0, NULL,
                                            pd2.ip_sum, icmpsum,
                                            pd->ip_sum, 0, pd2.af);
                                } else {
                                        pf_change_icmp(pd2.dst, NULL,
                                            saddr,
                                            &(*state)->state_key->gwy.addr,
                                            0, NULL,
                                            pd2.ip_sum, icmpsum,
                                            pd->ip_sum, 0, pd2.af);
                                }
                                switch (pd2.af) {
#ifdef INET
                                case AF_INET:
                                        m_copyback(m, off, ICMP_MINLEN,
                                            pd->hdr.icmp);
                                        m_copyback(m, ipoff2, sizeof(h2), &h2);
                                        break;
#endif /* INET */
#ifdef INET6
                                case AF_INET6:
                                        m_copyback(m, off,
                                            sizeof(struct icmp6_hdr),
                                            pd->hdr.icmp6);
                                        m_copyback(m, ipoff2, sizeof(h2_6),
                                            &h2_6);
                                        break;
#endif /* INET6 */
                                }
                        }

                        return (PF_PASS);
                        break;
                }
                }
        }
}

int
pf_test_state_other(struct pf_state **state, int direction, struct pfi_kif *kif,
    struct pf_pdesc *pd)
{
        struct pf_state_peer    *src, *dst;
        struct pf_state_key_cmp  key;

        key.af = pd->af;
        key.proto = pd->proto;
        if (direction == PF_IN) {
                PF_ACPY(&key.ext.addr, pd->src, key.af);
                PF_ACPY(&key.gwy.addr, pd->dst, key.af);
                key.ext.port = 0;
                key.gwy.port = 0;
        } else {
                PF_ACPY(&key.lan.addr, pd->src, key.af);
                PF_ACPY(&key.ext.addr, pd->dst, key.af);
                key.lan.port = 0;
                key.ext.port = 0;
        }

        STATE_LOOKUP();

        if (direction == (*state)->state_key->direction) {
                src = &(*state)->src;
                dst = &(*state)->dst;
        } else {
                src = &(*state)->dst;
                dst = &(*state)->src;
        }

        /* update states */
        if (src->state < PFOTHERS_SINGLE)
                src->state = PFOTHERS_SINGLE;
        if (dst->state == PFOTHERS_SINGLE)
                dst->state = PFOTHERS_MULTIPLE;

        /* update expire time */
        (*state)->expire = time_second;
        if (src->state == PFOTHERS_MULTIPLE && dst->state == PFOTHERS_MULTIPLE)
                (*state)->timeout = PFTM_OTHER_MULTIPLE;
        else
                (*state)->timeout = PFTM_OTHER_SINGLE;

        /* translate source/destination address, if necessary */
        if (STATE_TRANSLATE((*state)->state_key)) {
                if (direction == PF_OUT)
                        switch (pd->af) {
#ifdef INET
                        case AF_INET:
                                pf_change_a(&pd->src->v4.s_addr,
                                    pd->ip_sum,
                                    (*state)->state_key->gwy.addr.v4.s_addr,
                                    0);
                                break;
#endif /* INET */
#ifdef INET6
                        case AF_INET6:
                                PF_ACPY(pd->src,
                                    &(*state)->state_key->gwy.addr, pd->af);
                                break;
#endif /* INET6 */
                        }
                else
                        switch (pd->af) {
#ifdef INET
                        case AF_INET:
                                pf_change_a(&pd->dst->v4.s_addr,
                                    pd->ip_sum,
                                    (*state)->state_key->lan.addr.v4.s_addr,
                                    0);
                                break;
#endif /* INET */
#ifdef INET6
                        case AF_INET6:
                                PF_ACPY(pd->dst,
                                    &(*state)->state_key->lan.addr, pd->af);
                                break;
#endif /* INET6 */
                        }
        }

        return (PF_PASS);
}

/*
 * ipoff and off are measured from the start of the mbuf chain.
 * h must be at "ipoff" on the mbuf chain.
 */
void *
pf_pull_hdr(struct mbuf *m, int off, void *p, int len,
    u_short *actionp, u_short *reasonp, sa_family_t af)
{
        switch (af) {
#ifdef INET
        case AF_INET: {
                struct ip       *h = mtod(m, struct ip *);
                u_int16_t        fragoff = (ntohs(h->ip_off) & IP_OFFMASK) << 3;

                if (fragoff) {
                        if (fragoff >= len)
                                ACTION_SET(actionp, PF_PASS);
                        else {
                                ACTION_SET(actionp, PF_DROP);
                                REASON_SET(reasonp, PFRES_FRAG);
                        }
                        return (NULL);
                }
                if (m->m_pkthdr.len < off + len ||
                    ntohs(h->ip_len) < off + len) {
                        ACTION_SET(actionp, PF_DROP);
                        REASON_SET(reasonp, PFRES_SHORT);
                        return (NULL);
                }
                break;
        }
#endif /* INET */
#ifdef INET6
        case AF_INET6: {
                struct ip6_hdr  *h = mtod(m, struct ip6_hdr *);

                if (m->m_pkthdr.len < off + len ||
                    (ntohs(h->ip6_plen) + sizeof(struct ip6_hdr)) <
                    (unsigned)(off + len)) {
                        ACTION_SET(actionp, PF_DROP);
                        REASON_SET(reasonp, PFRES_SHORT);
                        return (NULL);
                }
                break;
        }
#endif /* INET6 */
        }
        m_copydata(m, off, len, p);
        return (p);
}

int
pf_routable(struct pf_addr *addr, sa_family_t af, struct pfi_kif *kif)
{
#ifdef __NetBSD__
        union {
                struct sockaddr         dst;
                struct sockaddr_in      dst4;
                struct sockaddr_in6     dst6;
        } u;
        struct route             ro;
        int                      ret = 1;
        struct rtentry          *rt;

        bzero(&ro, sizeof(ro));
        switch (af) {
        case AF_INET:
                sockaddr_in_init(&u.dst4, &addr->v4, 0);
                break;
#ifdef INET6
        case AF_INET6:
                sockaddr_in6_init(&u.dst6, &addr->v6, 0, 0, 0);
                break;
#endif /* INET6 */
        default:
                return (0);
        }
        rtcache_setdst(&ro, &u.dst);

        rt = rtcache_init(&ro);
        ret = rt != NULL ? 1 : 0;
        if (rt != NULL)
                rtcache_unref(rt, &ro);
        rtcache_free(&ro);

        return (ret);
#else /* !__NetBSD__ */
        struct sockaddr_in      *dst;
        int                      ret = 1;
        int                      check_mpath;
        extern int               ipmultipath;
#ifdef INET6
        extern int               ip6_multipath;
        struct sockaddr_in6     *dst6;
        struct route_in6         ro;
#else
        struct route             ro;
#endif
        struct radix_node       *rn;
        struct rtentry          *rt;
        struct ifnet            *ifp;

        check_mpath = 0;
        bzero(&ro, sizeof(ro));
        switch (af) {
        case AF_INET:
                dst = satosin(&ro.ro_dst);
                dst->sin_family = AF_INET;
                dst->sin_len = sizeof(*dst);
                dst->sin_addr = addr->v4;
                if (ipmultipath)
                        check_mpath = 1;
                break;
#ifdef INET6
        case AF_INET6:
                dst6 = (struct sockaddr_in6 *)&ro.ro_dst;
                dst6->sin6_family = AF_INET6;
                dst6->sin6_len = sizeof(*dst6);
                dst6->sin6_addr = addr->v6;
                if (ip6_multipath)
                        check_mpath = 1;
                break;
#endif /* INET6 */
        default:
                return (0);
        }

        /* Skip checks for ipsec interfaces */
        if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC)
                goto out;

        rtalloc_noclone((struct route *)&ro, NO_CLONING);

        if (ro.ro_rt != NULL) {
                /* No interface given, this is a no-route check */
                if (kif == NULL)
                        goto out;

                if (kif->pfik_ifp == NULL) {
                        ret = 0;
                        goto out;
                }

                /* Perform uRPF check if passed input interface */
                ret = 0;
                rn = (struct radix_node *)ro.ro_rt;
                do {
                        rt = (struct rtentry *)rn;
                        if (rt->rt_ifp->if_type == IFT_CARP)
                                ifp = rt->rt_ifp->if_carpdev;
                        else
                                ifp = rt->rt_ifp;

                        if (kif->pfik_ifp == ifp)
                                ret = 1;
                        rn = rn_mpath_next(rn);
                } while (check_mpath == 1 && rn != NULL && ret == 0);
        } else
                ret = 0;
out:
        if (ro.ro_rt != NULL)
                RTFREE(ro.ro_rt);
        return (ret);
#endif /* !__NetBSD__ */
}

int
pf_rtlabel_match(struct pf_addr *addr, sa_family_t af, struct pf_addr_wrap *aw)
{
#ifdef __NetBSD__
        /* NetBSD doesn't have route labels. */

        return (0);
#else
        struct sockaddr_in      *dst;
#ifdef INET6
        struct sockaddr_in6     *dst6;
        struct route_in6         ro;
#else
        struct route             ro;
#endif
        int                      ret = 0;

        bzero(&ro, sizeof(ro));
        switch (af) {
        case AF_INET:
                dst = satosin(&ro.ro_dst);
                dst->sin_family = AF_INET;
                dst->sin_len = sizeof(*dst);
                dst->sin_addr = addr->v4;
                break;
#ifdef INET6
        case AF_INET6:
                dst6 = (struct sockaddr_in6 *)&ro.ro_dst;
                dst6->sin6_family = AF_INET6;
                dst6->sin6_len = sizeof(*dst6);
                dst6->sin6_addr = addr->v6;
                break;
#endif /* INET6 */
        default:
                return (0);
        }

        rtalloc_noclone((struct route *)&ro, NO_CLONING);

        if (ro.ro_rt != NULL) {
                if (ro.ro_rt->rt_labelid == aw->v.rtlabel)
                        ret = 1;
                RTFREE(ro.ro_rt);
        }

        return (ret);
#endif /* !__NetBSD__ */
}

#ifdef INET
void
pf_route(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
    struct pf_state *s, struct pf_pdesc *pd)
{
        struct mbuf             *m0, *m1;
        struct route             iproute;
        struct route            *ro = NULL;
        const struct sockaddr   *dst;
        union {
                struct sockaddr         dst;
                struct sockaddr_in      dst4;
        } u;
        struct ip               *ip;
        struct ifnet            *ifp = NULL;
        struct pf_addr           naddr;
        struct pf_src_node      *sn = NULL;
        int                      error = 0;
#ifdef __NetBSD__
        struct pf_mtag          *pf_mtag;
#endif /* __NetBSD__ */

        if (m == NULL || *m == NULL || r == NULL ||
            (dir != PF_IN && dir != PF_OUT) || oifp == NULL)
                panic("pf_route: invalid parameters");

#ifdef __NetBSD__
        if ((pf_mtag = pf_get_mtag(*m)) == NULL) {
                m0 = *m;
                *m = NULL;
                goto bad;
        }
        if (pf_mtag->routed++ > 3) {
                m0 = *m;
                *m = NULL;
                goto bad;
        }
#else
        if ((*m)->m_pkthdr.pf.routed++ > 3) {
                m0 = *m;
                *m = NULL;
                goto bad;
        }
#endif /* !__NetBSD__ */

        if (r->rt == PF_DUPTO) {
                if ((m0 = m_dup(*m, 0, M_COPYALL, M_NOWAIT)) == NULL)
                        return;
        } else {
                if ((r->rt == PF_REPLYTO) == (r->direction == dir))
                        return;
                m0 = *m;
        }

        if (m0->m_len < sizeof(struct ip)) {
                DPFPRINTF(PF_DEBUG_URGENT,
                    ("pf_route: m0->m_len < sizeof(struct ip)\n"));
                goto bad;
        }

        ip = mtod(m0, struct ip *);

        ro = &iproute;
        memset(ro, 0, sizeof(*ro));
        sockaddr_in_init(&u.dst4, &ip->ip_dst, 0);
        dst = &u.dst;
        rtcache_setdst(ro, dst);

        if (r->rt == PF_FASTROUTE) {
                struct rtentry *rt;

                rt = rtcache_init(ro);

                if (rt == NULL) {
                        ip_statinc(IP_STAT_NOROUTE);
                        goto bad;
                }

                ifp = rt->rt_ifp;
                rt->rt_use++;

                if (rt->rt_flags & RTF_GATEWAY)
                        dst = rt->rt_gateway;
                rtcache_unref(rt, ro); /* FIXME dst is NOMPSAFE */
        } else {
                if (TAILQ_EMPTY(&r->rpool.list)) {
                        DPFPRINTF(PF_DEBUG_URGENT,
                            ("pf_route: TAILQ_EMPTY(&r->rpool.list)\n"));
                        goto bad;
                }
                if (s == NULL) {
                        pf_map_addr(AF_INET, r,
                            (const struct pf_addr *)&ip->ip_src,
                            &naddr, NULL, &sn);
                        if (!PF_AZERO(&naddr, AF_INET))
                                u.dst4.sin_addr.s_addr = naddr.v4.s_addr;
                        ifp = r->rpool.cur->kif ?
                            r->rpool.cur->kif->pfik_ifp : NULL;
                } else {
                        if (!PF_AZERO(&s->rt_addr, AF_INET))
                                u.dst4.sin_addr.s_addr = s->rt_addr.v4.s_addr;
                        ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
                }
        }
        if (ifp == NULL)
                goto bad;

        if (oifp != ifp) {
                if (pf_test(PF_OUT, ifp, &m0, NULL) != PF_PASS)
                        goto bad;
                else if (m0 == NULL)
                        goto done;
                if (m0->m_len < sizeof(struct ip)) {
                        DPFPRINTF(PF_DEBUG_URGENT,
                            ("pf_route: m0->m_len < sizeof(struct ip)\n"));
                        goto bad;
                }
                ip = mtod(m0, struct ip *);
        }

        /* Copied from ip_output. */

        /* Catch routing changes wrt. hardware checksumming for TCP or UDP. */
#ifdef __NetBSD__
        if (m0->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) {
                in_undefer_cksum_tcpudp(m0);
                m0->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4);
        }
#else
        if (m0->m_pkthdr.csum_flags & M_TCPV4_CSUM_OUT) {
                if (!(ifp->if_capabilities & IFCAP_CSUM_TCPv4) ||
                    ifp->if_bridge != NULL) {
                        in_delayed_cksum(m0);
                        m0->m_pkthdr.csum_flags &= ~M_TCPV4_CSUM_OUT; /* Clear */
                }
        } else if (m0->m_pkthdr.csum_flags & M_UDPV4_CSUM_OUT) {
                if (!(ifp->if_capabilities & IFCAP_CSUM_UDPv4) ||
                    ifp->if_bridge != NULL) {
                        in_delayed_cksum(m0);
                        m0->m_pkthdr.csum_flags &= ~M_UDPV4_CSUM_OUT; /* Clear */
                }
        }
#endif /* !__NetBSD__ */

        if (ntohs(ip->ip_len) <= ifp->if_mtu) {
#ifdef __NetBSD__
                ip->ip_sum = 0;
                ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);

                m0->m_pkthdr.csum_flags &= ~M_CSUM_IPv4;
#else
                if ((ifp->if_capabilities & IFCAP_CSUM_IPv4) &&
                    ifp->if_bridge == NULL) {
                        m0->m_pkthdr.csum_flags |= M_IPV4_CSUM_OUT;
                        ipstat.ips_outhwcsum++;
                } else {
                        ip->ip_sum = 0;
                        ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);
                }
                /* Update relevant hardware checksum stats for TCP/UDP */
                if (m0->m_pkthdr.csum_flags & M_TCPV4_CSUM_OUT)
                        tcpstat.tcps_outhwcsum++;
                else if (m0->m_pkthdr.csum_flags & M_UDPV4_CSUM_OUT)
                        udpstat.udps_outhwcsum++;
#endif /* !__NetBSD__ */
                error = if_output_lock(ifp, ifp, m0, dst, NULL);
                goto done;
        }

        /*
         * Too large for interface; fragment if possible.
         * Must be able to put at least 8 bytes per fragment.
         */
        if (ip->ip_off & htons(IP_DF)) {
                ip_statinc(IP_STAT_CANTFRAG);
                if (r->rt != PF_DUPTO) {
                        icmp_error(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 0,
                            ifp->if_mtu);
                        goto done;
                } else
                        goto bad;
        }

#ifdef __NetBSD__
        /* Make ip_fragment re-compute checksums. */
        if (IN_NEED_CHECKSUM(ifp, M_CSUM_IPv4)) {
                m0->m_pkthdr.csum_flags |= M_CSUM_IPv4;
        }
#endif /* __NetBSD__ */
        m1 = m0;
        error = ip_fragment(m0, ifp, ifp->if_mtu);
        if (error) {
                m0 = NULL;
                goto bad;
        }

        for (m0 = m1; m0; m0 = m1) {
                m1 = m0->m_nextpkt;
                m0->m_nextpkt = 0;
                if (error == 0)
                        error = (*ifp->if_output)(ifp, m0, dst, NULL);
                else
                        m_freem(m0);
        }

        if (error == 0)
                ip_statinc(IP_STAT_FRAGMENTED);

done:
        if (r->rt != PF_DUPTO)
                *m = NULL;
        if (ro == &iproute)
                rtcache_free(ro);
        return;

bad:
        m_freem(m0);
        goto done;
}
#endif /* INET */

#ifdef INET6
void
pf_route6(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
    struct pf_state *s, struct pf_pdesc *pd)
{
        struct mbuf             *m0;
        struct sockaddr_in6      dst;
        struct ip6_hdr          *ip6;
        struct ifnet            *ifp = NULL;
        struct pf_addr           naddr;
        struct pf_src_node      *sn = NULL;
#ifdef __NetBSD__
        struct pf_mtag          *pf_mtag;
#endif /* __NetBSD__ */

        if (m == NULL || *m == NULL || r == NULL ||
            (dir != PF_IN && dir != PF_OUT) || oifp == NULL)
                panic("pf_route6: invalid parameters");

#ifdef __NetBSD__
        if ((pf_mtag = pf_get_mtag(*m)) == NULL) {
                m0 = *m;
                *m = NULL;
                goto bad;
        }
        if (pf_mtag->routed++ > 3) {
                m0 = *m;
                *m = NULL;
                goto bad;
        }
#else
        if ((*m)->m_pkthdr.pf.routed++ > 3) {
                m0 = *m;
                *m = NULL;
                goto bad;
        }
#endif /* !__NetBSD__ */

        if (r->rt == PF_DUPTO) {
                if ((m0 = m_dup(*m, 0, M_COPYALL, M_NOWAIT)) == NULL)
                        return;
        } else {
                if ((r->rt == PF_REPLYTO) == (r->direction == dir))
                        return;
                m0 = *m;
        }

        if (m0->m_len < sizeof(struct ip6_hdr)) {
                DPFPRINTF(PF_DEBUG_URGENT,
                    ("pf_route6: m0->m_len < sizeof(struct ip6_hdr)\n"));
                goto bad;
        }
        ip6 = mtod(m0, struct ip6_hdr *);

        dst.sin6_family = AF_INET6;
        dst.sin6_len = sizeof(dst);
        dst.sin6_addr = ip6->ip6_dst;

        /* Cheat. XXX why only in the v6 case??? */
        if (r->rt == PF_FASTROUTE) {
#ifdef __NetBSD__
                pf_mtag->flags |= PF_TAG_GENERATED;
#else
                m0->m_pkthdr.pf.flags |= PF_TAG_GENERATED;
#endif /* !__NetBSD__ */
                ip6_output(m0, NULL, NULL, 0, NULL, NULL, NULL);
                return;
        }

        if (TAILQ_EMPTY(&r->rpool.list)) {
                DPFPRINTF(PF_DEBUG_URGENT,
                    ("pf_route6: TAILQ_EMPTY(&r->rpool.list)\n"));
                goto bad;
        }
        if (s == NULL) {
                pf_map_addr(AF_INET6, r, (struct pf_addr *)&ip6->ip6_src,
                    &naddr, NULL, &sn);
                if (!PF_AZERO(&naddr, AF_INET6))
                        PF_ACPY((struct pf_addr *)&dst.sin6_addr,
                            &naddr, AF_INET6);
                ifp = r->rpool.cur->kif ? r->rpool.cur->kif->pfik_ifp : NULL;
        } else {
                if (!PF_AZERO(&s->rt_addr, AF_INET6))
                        PF_ACPY((struct pf_addr *)&dst.sin6_addr,
                            &s->rt_addr, AF_INET6);
                ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
        }
        if (ifp == NULL)
                goto bad;

        if (oifp != ifp) {
                if (pf_test6(PF_OUT, ifp, &m0, NULL) != PF_PASS)
                        goto bad;
                else if (m0 == NULL)
                        goto done;
                if (m0->m_len < sizeof(struct ip6_hdr)) {
                        DPFPRINTF(PF_DEBUG_URGENT,
                            ("pf_route6: m0->m_len < sizeof(struct ip6_hdr)\n"));
                        goto bad;
                }
                ip6 = mtod(m0, struct ip6_hdr *);
        }

        /*
         * If the packet is too large for the outgoing interface,
         * send back an icmp6 error.
         */
        if (IN6_IS_SCOPE_EMBEDDABLE(&dst.sin6_addr))
                dst.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
        if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu) {
                (void)ip6_if_output(ifp, ifp, m0, &dst, NULL);
        } else {
                in6_ifstat_inc(ifp, ifs6_in_toobig);
                if (r->rt != PF_DUPTO)
                        icmp6_error(m0, ICMP6_PACKET_TOO_BIG, 0, ifp->if_mtu);
                else
                        goto bad;
        }

done:
        if (r->rt != PF_DUPTO)
                *m = NULL;
        return;

bad:
        m_freem(m0);
        goto done;
}
#endif /* INET6 */


/*
 * check protocol (tcp/udp/icmp/icmp6) checksum and set mbuf flag
 *   off is the offset where the protocol header starts
 *   len is the total length of protocol header plus payload
 * returns 0 when the checksum is valid, otherwise returns 1.
 */
#ifdef __NetBSD__
int
pf_check_proto_cksum(struct mbuf *m, int direction, int off, int len,
    u_int8_t p, sa_family_t af)
#else
int
pf_check_proto_cksum(struct mbuf *m, int off, int len, u_int8_t p,
    sa_family_t af)
#endif /* !__NetBSD__ */
{
#ifndef __NetBSD__
        u_int16_t flag_ok, flag_bad;
#endif /* !__NetBSD__ */
        u_int16_t sum;

#ifndef __NetBSD__
        switch (p) {
        case IPPROTO_TCP:
                flag_ok = M_TCP_CSUM_IN_OK;
                flag_bad = M_TCP_CSUM_IN_BAD;
                break;
        case IPPROTO_UDP:
                flag_ok = M_UDP_CSUM_IN_OK;
                flag_bad = M_UDP_CSUM_IN_BAD;
                break;
        case IPPROTO_ICMP:
#ifdef INET6
        case IPPROTO_ICMPV6:
#endif /* INET6 */
                flag_ok = flag_bad = 0;
                break;
        default:
                return (1);
        }
        if (m->m_pkthdr.csum_flags & flag_ok)
                return (0);
        if (m->m_pkthdr.csum_flags & flag_bad)
                return (1);
#endif /* !__NetBSD__ */
        if (off < sizeof(struct ip) || len < sizeof(struct udphdr))
                return (1);
        if (m->m_pkthdr.len < off + len)
                return (1);
#ifdef __NetBSD__
        if (direction == PF_IN) {
                switch (p) {
                case IPPROTO_TCP: {
                        struct tcphdr th; /* XXX */
                        int thlen;

                        m_copydata(m, off, sizeof(th), &th); /* XXX */
                        thlen = th.th_off << 2;
                        return tcp_input_checksum(af, m, &th, off,
                            thlen, len - thlen) != 0;
                }

                case IPPROTO_UDP: {
                        struct udphdr uh; /* XXX */

                        m_copydata(m, off, sizeof(uh), &uh); /* XXX */
                        return udp_input_checksum(af, m, &uh, off, len) != 0;
                }
                }
        }
#endif /* __NetBSD__ */
        switch (af) {
#ifdef INET
        case AF_INET:
                if (p == IPPROTO_ICMP) {
                        if (m->m_len < off)
                                return (1);
                        m->m_data += off;
                        m->m_len -= off;
                        sum = in_cksum(m, len);
                        m->m_data -= off;
                        m->m_len += off;
                } else {
                        if (m->m_len < sizeof(struct ip))
                                return (1);
                        sum = in4_cksum(m, p, off, len);
                }
                break;
#endif /* INET */
#ifdef INET6
        case AF_INET6:
                if (m->m_len < sizeof(struct ip6_hdr))
                        return (1);
                sum = in6_cksum(m, p, off, len);
                break;
#endif /* INET6 */
        default:
                return (1);
        }
        if (sum) {
#ifndef __NetBSD__
                m->m_pkthdr.csum_flags |= flag_bad;
#endif /* !__NetBSD__ */
                switch (p) {
                case IPPROTO_TCP:
                        tcp_statinc(TCP_STAT_RCVBADSUM);
                        break;
                case IPPROTO_UDP:
                        udp_statinc(UDP_STAT_BADSUM);
                        break;
                case IPPROTO_ICMP:
                        icmp_statinc(ICMP_STAT_CHECKSUM);
                        break;
#ifdef INET6
                case IPPROTO_ICMPV6:
                        icmp6_statinc(ICMP6_STAT_CHECKSUM);
                        break;
#endif /* INET6 */
                }
                return (1);
        }
#ifndef __NetBSD__
        m->m_pkthdr.csum_flags |= flag_ok;
#endif /* !__NetBSD__ */
        return (0);
}

#ifdef INET
int
pf_test(int dir, struct ifnet *ifp, struct mbuf **m0,
    struct ether_header *eh)
{
        struct pfi_kif          *kif;
        u_short                  action, reason = 0, log = 0;
        struct mbuf             *m = *m0;
        struct ip               *h = NULL;
        struct pf_rule          *a = NULL, *r = &pf_default_rule, *tr, *nr;
        struct pf_state         *s = NULL;
        struct pf_state_key     *sk = NULL;
        struct pf_ruleset       *ruleset = NULL;
        struct pf_pdesc          pd;
        int                      off, dirndx;
#ifdef __NetBSD__
        struct pf_mtag          *pf_mtag = NULL; /* XXX gcc */
#if defined(ALTQ)
        int pqid = 0;
#endif
#endif /* __NetBSD__ */

        if (!pf_status.running)
                return (PF_PASS);

        memset(&pd, 0, sizeof(pd));
        if (ifp->if_type == IFT_CARP && ifp->if_carpdev)
                kif = (struct pfi_kif *)ifp->if_carpdev->if_pf_kif;
        else
                kif = (struct pfi_kif *)ifp->if_pf_kif;

        if (kif == NULL) {
                DPFPRINTF(PF_DEBUG_URGENT,
                    ("pf_test: kif == NULL, if_xname %s\n", ifp->if_xname));
                return (PF_DROP);
        }
        if (kif->pfik_flags & PFI_IFLAG_SKIP)
                return (PF_PASS);

#ifdef DIAGNOSTIC
        if ((m->m_flags & M_PKTHDR) == 0)
                panic("non-M_PKTHDR is passed to pf_test");
#endif /* DIAGNOSTIC */

        if (m->m_pkthdr.len < (int)sizeof(*h)) {
                action = PF_DROP;
                REASON_SET_NOPTR(&reason, PFRES_SHORT);
                log = 1;
                goto done;
        }

#ifdef __NetBSD__
        if ((pf_mtag = pf_get_mtag(m)) == NULL) {
                DPFPRINTF(PF_DEBUG_URGENT,
                    ("pf_test: pf_get_mtag returned NULL\n"));
                return (PF_DROP);
        }
        if (pf_mtag->flags & PF_TAG_GENERATED)
                return (PF_PASS);
#else
        if (m->m_pkthdr.pf.flags & PF_TAG_GENERATED)
                return (PF_PASS);
#endif /* !__NetBSD__ */

        /* We do IP header normalization and packet reassembly here */
        if (pf_normalize_ip(m0, dir, kif, &reason, &pd) != PF_PASS) {
                action = PF_DROP;
                goto done;
        }
        m = *m0;        /* pf_normalize messes with m0 */
        h = mtod(m, struct ip *);

        off = h->ip_hl << 2;
        if (off < (int)sizeof(*h)) {
                action = PF_DROP;
                REASON_SET_NOPTR(&reason, PFRES_SHORT);
                log = 1;
                goto done;
        }

        pd.src = (struct pf_addr *)&h->ip_src;
        pd.dst = (struct pf_addr *)&h->ip_dst;
        PF_ACPY(&pd.baddr, dir == PF_OUT ? pd.src : pd.dst, AF_INET);
        pd.ip_sum = &h->ip_sum;
        pd.proto = h->ip_p;
        pd.af = AF_INET;
        pd.tos = h->ip_tos;
        pd.tot_len = ntohs(h->ip_len);
        pd.eh = eh;

        /* handle fragments that didn't get reassembled by normalization */
        if (h->ip_off & htons(IP_MF | IP_OFFMASK)) {
                action = pf_test_fragment(&r, dir, kif, m, h,
                    &pd, &a, &ruleset);
                goto done;
        }

        switch (h->ip_p) {

        case IPPROTO_TCP: {
                struct tcphdr   th;

                pd.hdr.tcp = &th;
                if (!pf_pull_hdr(m, off, &th, sizeof(th),
                    &action, &reason, AF_INET)) {
                        log = action != PF_PASS;
                        goto done;
                }
                pd.p_len = pd.tot_len - off - (th.th_off << 2);
#if defined(ALTQ) && defined(__NetBSD__)
                if ((th.th_flags & TH_ACK) && pd.p_len == 0)
                        pqid = 1;
#endif
                action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
                if (action == PF_DROP)
                        goto done;
                action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
                    &reason);
                if (action == PF_PASS) {
#if NPFSYNC
                        pfsync_update_state(s);
#endif /* NPFSYNC */
                        r = s->rule.ptr;
                        a = s->anchor.ptr;
                        log = s->log;
                } else if (s == NULL)
                        action = pf_test_rule(&r, &s, dir, kif,
                            m, off, h, &pd, &a, &ruleset, NULL);
                break;
        }

        case IPPROTO_UDP: {
                struct udphdr   uh;

                pd.hdr.udp = &uh;
                if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
                    &action, &reason, AF_INET)) {
                        log = action != PF_PASS;
                        goto done;
                }
                if (uh.uh_dport == 0 ||
                    ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
                    ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
                        action = PF_DROP;
                        REASON_SET_NOPTR(&reason, PFRES_SHORT);
                        goto done;
                }
                action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
                if (action == PF_PASS) {
#if NPFSYNC
                        pfsync_update_state(s);
#endif /* NPFSYNC */
                        r = s->rule.ptr;
                        a = s->anchor.ptr;
                        log = s->log;
                } else if (s == NULL)
                        action = pf_test_rule(&r, &s, dir, kif,
                            m, off, h, &pd, &a, &ruleset, NULL);
                break;
        }

        case IPPROTO_ICMP: {
                struct icmp     ih;

                pd.hdr.icmp = &ih;
                if (!pf_pull_hdr(m, off, &ih, ICMP_MINLEN,
                    &action, &reason, AF_INET)) {
                        log = action != PF_PASS;
                        goto done;
                }
                action = pf_test_state_icmp(&s, dir, kif, m, off, h, &pd,
                    &reason);
                if (action == PF_PASS) {
#if NPFSYNC
                        pfsync_update_state(s);
#endif /* NPFSYNC */
                        r = s->rule.ptr;
                        a = s->anchor.ptr;
                        log = s->log;
                } else if (s == NULL)
                        action = pf_test_rule(&r, &s, dir, kif,
                            m, off, h, &pd, &a, &ruleset, NULL);
                break;
        }

#ifdef INET6
        case IPPROTO_ICMPV6: {
                action = PF_DROP;
                DPFPRINTF(PF_DEBUG_MISC,
                    ("pf: dropping IPv4 packet with ICMPv6 payload\n"));
                goto done;
        }
#endif

        default:
                action = pf_test_state_other(&s, dir, kif, &pd);
                if (action == PF_PASS) {
#if NPFSYNC
                        pfsync_update_state(s);
#endif /* NPFSYNC */
                        r = s->rule.ptr;
                        a = s->anchor.ptr;
                        log = s->log;
                } else if (s == NULL)
                        action = pf_test_rule(&r, &s, dir, kif, m, off, h,
                            &pd, &a, &ruleset, NULL);
                break;
        }

done:
        if (action == PF_PASS && h->ip_hl > 5 &&
            !((s && s->allow_opts) || r->allow_opts)) {
                action = PF_DROP;
                REASON_SET_NOPTR(&reason, PFRES_IPOPTIONS);
                log = 1;
                DPFPRINTF(PF_DEBUG_MISC,
                    ("pf: dropping packet with ip options\n"));
        }

        if ((s && s->tag) || r->rtableid)
                pf_tag_packet(m, s ? s->tag : 0, r->rtableid);

#ifdef ALTQ
        if (action == PF_PASS && r->qid) {
#ifdef __NetBSD__
                struct m_tag    *mtag;
                struct altq_tag *atag;

                mtag = m_tag_get(PACKET_TAG_ALTQ_QID, sizeof(*atag), M_NOWAIT);
                if (mtag != NULL) {
                        atag = (struct altq_tag *)(mtag + 1);
                        if (pqid || (pd.tos & IPTOS_LOWDELAY))
                                atag->qid = r->pqid;
                        else
                                atag->qid = r->qid;
                        /* add hints for ecn */
                        atag->af = AF_INET;
                        atag->hdr = h;
                        m_tag_prepend(m, mtag);
                }
#else
                if (pqid || (pd.tos & IPTOS_LOWDELAY))
                        m->m_pkthdr.pf.qid = r->pqid;
                else
                        m->m_pkthdr.pf.qid = r->qid;
                /* add hints for ecn */
                m->m_pkthdr.pf.hdr = h;
#endif /* !__NetBSD__ */
        }
#endif /* ALTQ */

        /*
         * connections redirected to loopback should not match sockets
         * bound specifically to loopback due to security implications,
         * see tcp_input() and in_pcblookup_listen().
         */
        if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
            pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
            (s->nat_rule.ptr->action == PF_RDR ||
            s->nat_rule.ptr->action == PF_BINAT) &&
            (ntohl(pd.dst->v4.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET)
#ifdef __NetBSD__
                pf_mtag->flags |= PF_TAG_TRANSLATE_LOCALHOST;
#else
                m->m_pkthdr.pf.flags |= PF_TAG_TRANSLATE_LOCALHOST;
#endif /* !__NetBSD__ */

        if (log) {
#if NPFLOG > 0
                struct pf_rule *lr;

                if (s != NULL && s->nat_rule.ptr != NULL &&
                    s->nat_rule.ptr->log & PF_LOG_ALL)
                        lr = s->nat_rule.ptr;
                else
                        lr = r;
                PFLOG_PACKET(kif, h, m, AF_INET, dir, reason, lr, a, ruleset,
                    &pd);
#endif
        }

        kif->pfik_bytes[0][dir == PF_OUT][action != PF_PASS] += pd.tot_len;
        kif->pfik_packets[0][dir == PF_OUT][action != PF_PASS]++;

        if (action == PF_PASS || r->action == PF_DROP) {
                dirndx = (dir == PF_OUT);
                r->packets[dirndx]++;
                r->bytes[dirndx] += pd.tot_len;
                if (a != NULL) {
                        a->packets[dirndx]++;
                        a->bytes[dirndx] += pd.tot_len;
                }
                if (s != NULL) {
                        sk = s->state_key;
                        if (s->nat_rule.ptr != NULL) {
                                s->nat_rule.ptr->packets[dirndx]++;
                                s->nat_rule.ptr->bytes[dirndx] += pd.tot_len;
                        }
                        if (s->src_node != NULL) {
                                s->src_node->packets[dirndx]++;
                                s->src_node->bytes[dirndx] += pd.tot_len;
                        }
                        if (s->nat_src_node != NULL) {
                                s->nat_src_node->packets[dirndx]++;
                                s->nat_src_node->bytes[dirndx] += pd.tot_len;
                        }
                        dirndx = (dir == sk->direction) ? 0 : 1;
                        s->packets[dirndx]++;
                        s->bytes[dirndx] += pd.tot_len;
                }
                tr = r;
                nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
                if (nr != NULL) {
                        struct pf_addr *x;
                        /*
                         * XXX: we need to make sure that the addresses
                         * passed to pfr_update_stats() are the same than
                         * the addresses used during matching (pfr_match)
                         */
                        if (r == &pf_default_rule) {
                                tr = nr;
                                x = (sk == NULL || sk->direction == dir) ?
                                    &pd.baddr : &pd.naddr;
                        } else
                                x = (sk == NULL || sk->direction == dir) ?
                                    &pd.naddr : &pd.baddr;
                        if (x == &pd.baddr || s == NULL) {
                                /* we need to change the address */
                                if (dir == PF_OUT)
                                        pd.src = x;
                                else
                                        pd.dst = x;
                        }
                }
                if (tr->src.addr.type == PF_ADDR_TABLE)
                        pfr_update_stats(tr->src.addr.p.tbl, (sk == NULL ||
                            sk->direction == dir) ?
                            pd.src : pd.dst, pd.af,
                            pd.tot_len, dir == PF_OUT, r->action == PF_PASS,
                            tr->src.neg);
                if (tr->dst.addr.type == PF_ADDR_TABLE)
                        pfr_update_stats(tr->dst.addr.p.tbl, (sk == NULL ||
                            sk->direction == dir) ? pd.dst : pd.src, pd.af,
                            pd.tot_len, dir == PF_OUT, r->action == PF_PASS,
                            tr->dst.neg);
        }


        if (action == PF_SYNPROXY_DROP) {
                m_freem(*m0);
                *m0 = NULL;
                action = PF_PASS;
        } else if (r->rt)
                /* pf_route can free the mbuf causing *m0 to become NULL */
                pf_route(m0, r, dir, kif->pfik_ifp, s, &pd);

        return (action);
}
#endif /* INET */

#ifdef INET6
int
pf_test6(int dir, struct ifnet *ifp, struct mbuf **m0,
    struct ether_header *eh)
{
        struct pfi_kif          *kif;
        u_short                  action, reason = 0, log = 0;
        struct mbuf             *m = *m0, *n = NULL;
        struct ip6_hdr          *h = NULL; /* XXX gcc */
        struct pf_rule          *a = NULL, *r = &pf_default_rule, *tr, *nr;
        struct pf_state         *s = NULL;
        struct pf_state_key     *sk = NULL;
        struct pf_ruleset       *ruleset = NULL;
        struct pf_pdesc          pd;
        int                      off, terminal = 0, dirndx, rh_cnt = 0;
#ifdef __NetBSD__
        struct pf_mtag          *pf_mtag = NULL; /* XXX gcc */
#endif /* __NetBSD__ */

        if (!pf_status.running)
                return (PF_PASS);

        memset(&pd, 0, sizeof(pd));
        if (ifp->if_type == IFT_CARP && ifp->if_carpdev)
                kif = (struct pfi_kif *)ifp->if_carpdev->if_pf_kif;
        else
                kif = (struct pfi_kif *)ifp->if_pf_kif;

        if (kif == NULL) {
                DPFPRINTF(PF_DEBUG_URGENT,
                    ("pf_test6: kif == NULL, if_xname %s\n", ifp->if_xname));
                return (PF_DROP);
        }
        if (kif->pfik_flags & PFI_IFLAG_SKIP)
                return (PF_PASS);

#ifdef DIAGNOSTIC
        if ((m->m_flags & M_PKTHDR) == 0)
                panic("non-M_PKTHDR is passed to pf_test6");
#endif /* DIAGNOSTIC */

        if (m->m_pkthdr.len < (int)sizeof(*h)) {
                action = PF_DROP;
                REASON_SET_NOPTR(&reason, PFRES_SHORT);
                log = 1;
                goto done;
        }

#ifdef __NetBSD__
        if ((pf_mtag = pf_get_mtag(m)) == NULL) {
                DPFPRINTF(PF_DEBUG_URGENT,
                    ("pf_test6: pf_get_mtag returned NULL\n"));
                return (PF_DROP);
        }
        if (pf_mtag->flags & PF_TAG_GENERATED)
                return (PF_PASS);
#else
        if (m->m_pkthdr.pf.flags & PF_TAG_GENERATED)
                return (PF_PASS);
#endif /* !__NetBSD__ */

        /* We do IP header normalization and packet reassembly here */
        if (pf_normalize_ip6(m0, dir, kif, &reason, &pd) != PF_PASS) {
                action = PF_DROP;
                goto done;
        }
        m = *m0;        /* pf_normalize messes with m0 */
        h = mtod(m, struct ip6_hdr *);

#if 1
        /*
         * we do not support jumbogram yet.  if we keep going, zero ip6_plen
         * will do something bad, so drop the packet for now.
         */
        if (htons(h->ip6_plen) == 0) {
                action = PF_DROP;
                REASON_SET_NOPTR(&reason, PFRES_NORM);  /*XXX*/
                goto done;
        }
#endif

        pd.src = (struct pf_addr *)&h->ip6_src;
        pd.dst = (struct pf_addr *)&h->ip6_dst;
        PF_ACPY(&pd.baddr, dir == PF_OUT ? pd.src : pd.dst, AF_INET6);
        pd.ip_sum = NULL;
        pd.af = AF_INET6;
        pd.tos = 0;
        pd.tot_len = ntohs(h->ip6_plen) + sizeof(struct ip6_hdr);
        pd.eh = eh;

        off = ((char *)h - m->m_data) + sizeof(struct ip6_hdr);
        pd.proto = h->ip6_nxt;
        do {
                switch (pd.proto) {
                case IPPROTO_FRAGMENT:
                        action = pf_test_fragment(&r, dir, kif, m, h,
                            &pd, &a, &ruleset);
                        if (action == PF_DROP)
                                REASON_SET_NOPTR(&reason, PFRES_FRAG);
                        goto done;
                case IPPROTO_ROUTING: {
                        struct ip6_rthdr rthdr;

                        if (rh_cnt++) {
                                DPFPRINTF(PF_DEBUG_MISC,
                                    ("pf: IPv6 more than one rthdr\n"));
                                action = PF_DROP;
                                REASON_SET_NOPTR(&reason, PFRES_IPOPTIONS);
                                log = 1;
                                goto done;
                        }
                        if (!pf_pull_hdr(m, off, &rthdr, sizeof(rthdr), NULL,
                            &reason, pd.af)) {
                                DPFPRINTF(PF_DEBUG_MISC,
                                    ("pf: IPv6 short rthdr\n"));
                                action = PF_DROP;
                                REASON_SET_NOPTR(&reason, PFRES_SHORT);
                                log = 1;
                                goto done;
                        }
                        if (rthdr.ip6r_type == IPV6_RTHDR_TYPE_0) {
                                DPFPRINTF(PF_DEBUG_MISC,
                                    ("pf: IPv6 rthdr0\n"));
                                action = PF_DROP;
                                REASON_SET_NOPTR(&reason, PFRES_IPOPTIONS);
                                log = 1;
                                goto done;
                        }
                        /* FALLTHROUGH */
                }
                case IPPROTO_AH:
                case IPPROTO_HOPOPTS:
                case IPPROTO_DSTOPTS: {
                        /* get next header and header length */
                        struct ip6_ext  opt6;

                        if (!pf_pull_hdr(m, off, &opt6, sizeof(opt6),
                            NULL, &reason, pd.af)) {
                                DPFPRINTF(PF_DEBUG_MISC,
                                    ("pf: IPv6 short opt\n"));
                                action = PF_DROP;
                                log = 1;
                                goto done;
                        }
                        if (pd.proto == IPPROTO_AH)
                                off += (opt6.ip6e_len + 2) * 4;
                        else
                                off += (opt6.ip6e_len + 1) * 8;
                        pd.proto = opt6.ip6e_nxt;
                        /* goto the next header */
                        break;
                }
                default:
                        terminal++;
                        break;
                }
        } while (!terminal);

        /* if there's no routing header, use unmodified mbuf for checksumming */
        if (!n)
                n = m;

        switch (pd.proto) {

        case IPPROTO_TCP: {
                struct tcphdr   th;

                pd.hdr.tcp = &th;
                if (!pf_pull_hdr(m, off, &th, sizeof(th),
                    &action, &reason, AF_INET6)) {
                        log = action != PF_PASS;
                        goto done;
                }
                pd.p_len = pd.tot_len - off - (th.th_off << 2);
                action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
                if (action == PF_DROP)
                        goto done;
                action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
                    &reason);
                if (action == PF_PASS) {
#if NPFSYNC
                        pfsync_update_state(s);
#endif /* NPFSYNC */
                        r = s->rule.ptr;
                        a = s->anchor.ptr;
                        log = s->log;
                } else if (s == NULL)
                        action = pf_test_rule(&r, &s, dir, kif,
                            m, off, h, &pd, &a, &ruleset, NULL);
                break;
        }

        case IPPROTO_UDP: {
                struct udphdr   uh;

                pd.hdr.udp = &uh;
                if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
                    &action, &reason, AF_INET6)) {
                        log = action != PF_PASS;
                        goto done;
                }
                if (uh.uh_dport == 0 ||
                    ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
                    ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
                        action = PF_DROP;
                        REASON_SET_NOPTR(&reason, PFRES_SHORT);
                        goto done;
                }
                action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
                if (action == PF_PASS) {
#if NPFSYNC
                        pfsync_update_state(s);
#endif /* NPFSYNC */
                        r = s->rule.ptr;
                        a = s->anchor.ptr;
                        log = s->log;
                } else if (s == NULL)
                        action = pf_test_rule(&r, &s, dir, kif,
                            m, off, h, &pd, &a, &ruleset, NULL);
                break;
        }

#ifdef INET
        case IPPROTO_ICMP: {
                action = PF_DROP;
                DPFPRINTF(PF_DEBUG_MISC,
                    ("pf: dropping IPv6 packet with ICMPv4 payload\n"));
                goto done;
        }
#endif

        case IPPROTO_ICMPV6: {
                struct icmp6_hdr        ih;

                pd.hdr.icmp6 = &ih;
                if (!pf_pull_hdr(m, off, &ih, sizeof(ih),
                    &action, &reason, AF_INET6)) {
                        log = action != PF_PASS;
                        goto done;
                }
                action = pf_test_state_icmp(&s, dir, kif,
                    m, off, h, &pd, &reason);
                if (action == PF_PASS) {
#if NPFSYNC
                        pfsync_update_state(s);
#endif /* NPFSYNC */
                        r = s->rule.ptr;
                        a = s->anchor.ptr;
                        log = s->log;
                } else if (s == NULL)
                        action = pf_test_rule(&r, &s, dir, kif,
                            m, off, h, &pd, &a, &ruleset, NULL);
                break;
        }

        default:
                action = pf_test_state_other(&s, dir, kif, &pd);
                if (action == PF_PASS) {
#if NPFSYNC
                        pfsync_update_state(s);
#endif /* NPFSYNC */
                        r = s->rule.ptr;
                        a = s->anchor.ptr;
                        log = s->log;
                } else if (s == NULL)
                        action = pf_test_rule(&r, &s, dir, kif, m, off, h,
                            &pd, &a, &ruleset, NULL);
                break;
        }

done:
        if (n != m) {
                m_freem(n);
                n = NULL;
        }

        /* handle dangerous IPv6 extension headers. */
        if (action == PF_PASS && rh_cnt &&
            !((s && s->allow_opts) || r->allow_opts)) {
                action = PF_DROP;
                REASON_SET_NOPTR(&reason, PFRES_IPOPTIONS);
                log = 1;
                DPFPRINTF(PF_DEBUG_MISC,
                    ("pf: dropping packet with dangerous v6 headers\n"));
        }

        if ((s && s->tag) || r->rtableid)
                pf_tag_packet(m, s ? s->tag : 0, r->rtableid);

#ifdef ALTQ
        if (action == PF_PASS && r->qid) {
#ifdef __NetBSD__
                struct m_tag    *mtag;
                struct altq_tag *atag;

                mtag = m_tag_get(PACKET_TAG_ALTQ_QID, sizeof(*atag), M_NOWAIT);
                if (mtag != NULL) {
                        atag = (struct altq_tag *)(mtag + 1);
                        if (pd.tos & IPTOS_LOWDELAY)
                                atag->qid = r->pqid;
                        else
                                atag->qid = r->qid;
                        /* add hints for ecn */
                        atag->af = AF_INET6;
                        atag->hdr = h;
                        m_tag_prepend(m, mtag);
                }
#else
                if (pd.tos & IPTOS_LOWDELAY)
                        m->m_pkthdr.pf.qid = r->pqid;
                else
                        m->m_pkthdr.pf.qid = r->qid;
                /* add hints for ecn */
                m->m_pkthdr.pf.hdr = h;
#endif /* !__NetBSD__ */
        }
#endif /* ALTQ */

        if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
            pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
            (s->nat_rule.ptr->action == PF_RDR ||
            s->nat_rule.ptr->action == PF_BINAT) &&
            IN6_IS_ADDR_LOOPBACK(&pd.dst->v6))
#ifdef __NetBSD__
                pf_mtag->flags |= PF_TAG_TRANSLATE_LOCALHOST;
#else
                m->m_pkthdr.pf.flags |= PF_TAG_TRANSLATE_LOCALHOST;
#endif /* !__NetBSD__ */

        if (log) {
#if NPFLOG > 0
                struct pf_rule *lr;

                if (s != NULL && s->nat_rule.ptr != NULL &&
                    s->nat_rule.ptr->log & PF_LOG_ALL)
                        lr = s->nat_rule.ptr;
                else
                        lr = r;
                PFLOG_PACKET(kif, h, m, AF_INET6, dir, reason, lr, a, ruleset,
                    &pd);
#endif
        }

        kif->pfik_bytes[1][dir == PF_OUT][action != PF_PASS] += pd.tot_len;
        kif->pfik_packets[1][dir == PF_OUT][action != PF_PASS]++;

        if (action == PF_PASS || r->action == PF_DROP) {
                dirndx = (dir == PF_OUT);
                r->packets[dirndx]++;
                r->bytes[dirndx] += pd.tot_len;
                if (a != NULL) {
                        a->packets[dirndx]++;
                        a->bytes[dirndx] += pd.tot_len;
                }
                if (s != NULL) {
                        sk = s->state_key;
                        if (s->nat_rule.ptr != NULL) {
                                s->nat_rule.ptr->packets[dirndx]++;
                                s->nat_rule.ptr->bytes[dirndx] += pd.tot_len;
                        }
                        if (s->src_node != NULL) {
                                s->src_node->packets[dirndx]++;
                                s->src_node->bytes[dirndx] += pd.tot_len;
                        }
                        if (s->nat_src_node != NULL) {
                                s->nat_src_node->packets[dirndx]++;
                                s->nat_src_node->bytes[dirndx] += pd.tot_len;
                        }
                        dirndx = (dir == sk->direction) ? 0 : 1;
                        s->packets[dirndx]++;
                        s->bytes[dirndx] += pd.tot_len;
                }
                tr = r;
                nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
                if (nr != NULL) {
                        struct pf_addr *x;
                        /*
                         * XXX: we need to make sure that the addresses
                         * passed to pfr_update_stats() are the same than
                         * the addresses used during matching (pfr_match)
                         */
                        if (r == &pf_default_rule) {
                                tr = nr;
                                x = (s == NULL || sk->direction == dir) ?
                                    &pd.baddr : &pd.naddr;
                        } else {
                                x = (s == NULL || sk->direction == dir) ?
                                    &pd.naddr : &pd.baddr;
                        }
                        if (x == &pd.baddr || s == NULL) {
                                if (dir == PF_OUT)
                                        pd.src = x;
                                else
                                        pd.dst = x;
                        }
                }
                if (tr->src.addr.type == PF_ADDR_TABLE)
                        pfr_update_stats(tr->src.addr.p.tbl, (sk == NULL ||
                            sk->direction == dir) ? pd.src : pd.dst, pd.af,
                            pd.tot_len, dir == PF_OUT, r->action == PF_PASS,
                            tr->src.neg);
                if (tr->dst.addr.type == PF_ADDR_TABLE)
                        pfr_update_stats(tr->dst.addr.p.tbl, (sk == NULL ||
                            sk->direction == dir) ? pd.dst : pd.src, pd.af,
                            pd.tot_len, dir == PF_OUT, r->action == PF_PASS,
                            tr->dst.neg);
        }


        if (action == PF_SYNPROXY_DROP) {
                m_freem(*m0);
                *m0 = NULL;
                action = PF_PASS;
        } else if (r->rt)
                /* pf_route6 can free the mbuf causing *m0 to become NULL */
                pf_route6(m0, r, dir, kif->pfik_ifp, s, &pd);

        return (action);
}
#endif /* INET6 */

int
pf_check_congestion(struct ifqueue *ifq)
{
#ifdef __NetBSD__
        // XXX: not handled anyway
        KASSERT(ifq == NULL);
        return (0);
#else
        if (ifq->ifq_congestion)
                return (1);
        else
                return (0);
#endif /* !__NetBSD__ */
}