path: root/src/pluto/nat_traversal.c

/* FreeS/WAN NAT-Traversal
 * Copyright (C) 2002-2005 Mathieu Lafon - Arkoon Network Security
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * RCSID $Id: nat_traversal.c,v 1.8 2005/01/06 22:36:58 as Exp $
 */

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <stdarg.h>
#include <syslog.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>     /* used only if MSG_NOSIGNAL not defined */
#include <sys/queue.h>

#include <freeswan.h>
#include <ipsec_policy.h>
#include <pfkeyv2.h>
#include <pfkey.h>

#include "constants.h"
#include "defs.h"
#include "log.h"
#include "server.h"
#include "state.h"
#include "connections.h"
#include "packet.h"
#include "demux.h"
#include "kernel.h"
#include "whack.h"
#include "timer.h"
#include "cookie.h"
#include "sha1.h"
#include "md5.h"
#include "crypto.h"
#include "vendor.h"
#include "ike_alg.h"
#include "nat_traversal.h"

/* #define FORCE_NAT_TRAVERSAL */
#define NAT_D_DEBUG
#define NAT_T_SUPPORT_LAST_DRAFTS

#ifndef SOL_UDP
#define SOL_UDP 17
#endif

#ifndef UDP_ESPINUDP
#define UDP_ESPINUDP    100
#endif

#define DEFAULT_KEEP_ALIVE_PERIOD  20

#ifdef _IKE_ALG_H
/* Alg patch: hash_digest_len -> hash_digest_size */
#define hash_digest_len hash_digest_size
#endif

bool nat_traversal_enabled = FALSE;
bool nat_traversal_support_non_ike = FALSE;
bool nat_traversal_support_port_floating = FALSE;

static unsigned int _kap = 0;
static unsigned int _ka_evt = 0;
static bool _force_ka = 0;

static const char *natt_version = "0.6c";

void init_nat_traversal (bool activate, unsigned int keep_alive_period,
	bool fka, bool spf)
{
    nat_traversal_enabled = activate;
    nat_traversal_support_non_ike = activate;
#ifdef NAT_T_SUPPORT_LAST_DRAFTS
    nat_traversal_support_port_floating = activate ? spf : FALSE;
#endif
    _force_ka = fka;
    _kap = keep_alive_period ? keep_alive_period : DEFAULT_KEEP_ALIVE_PERIOD;
    plog("  including NAT-Traversal patch (Version %s)%s%s%s"
	 , natt_version, activate ? "" : " [disabled]"
	 , activate & fka ? " [Force KeepAlive]" : ""
	 , activate & !spf ? " [Port Floating disabled]" : "");
}

static void disable_nat_traversal (int type)
{
    if (type == ESPINUDP_WITH_NON_IKE)
	nat_traversal_support_non_ike = FALSE;
    else
	nat_traversal_support_port_floating = FALSE;

    if (!nat_traversal_support_non_ike &&
        !nat_traversal_support_port_floating)
	    nat_traversal_enabled = FALSE;
}

static void _natd_hash(const struct hash_desc *hasher, char *hash,
	u_int8_t *icookie, u_int8_t *rcookie,
	const ip_address *ip, u_int16_t port)
{
    union hash_ctx ctx;

    if (is_zero_cookie(icookie))
	DBG_log("_natd_hash: Warning, icookie is zero !!");
    if (is_zero_cookie(rcookie))
	DBG_log("_natd_hash: Warning, rcookie is zero !!");

    /**
     * draft-ietf-ipsec-nat-t-ike-01.txt
     *
     *   HASH = HASH(CKY-I | CKY-R | IP | Port)
     *
     * All values in network order
     */
    hasher->hash_init(&ctx);
    hasher->hash_update(&ctx, icookie, COOKIE_SIZE);
    hasher->hash_update(&ctx, rcookie, COOKIE_SIZE);
    switch (addrtypeof(ip)) {
    case AF_INET:
	hasher->hash_update(&ctx, (const u_char *)&ip->u.v4.sin_addr.s_addr
		, sizeof(ip->u.v4.sin_addr.s_addr));
	break;
    case AF_INET6:
	hasher->hash_update(&ctx, (const u_char *)&ip->u.v6.sin6_addr.s6_addr
		, sizeof(ip->u.v6.sin6_addr.s6_addr));
	break;
    }
    hasher->hash_update(&ctx, (const u_char *)&port, sizeof(u_int16_t));
    hasher->hash_final(hash, &ctx);
#ifdef NAT_D_DEBUG
    DBG(DBG_NATT,
	DBG_log("_natd_hash: hasher=%p(%d)", hasher, (int)hasher->hash_digest_len);
	DBG_dump("_natd_hash: icookie=", icookie, COOKIE_SIZE);
	DBG_dump("_natd_hash: rcookie=", rcookie, COOKIE_SIZE);
	switch (addrtypeof(ip)) {
	case AF_INET:
	    DBG_dump("_natd_hash: ip=", &ip->u.v4.sin_addr.s_addr
		, sizeof(ip->u.v4.sin_addr.s_addr));
	    break;
	}
	DBG_log("_natd_hash: port=%d", port);
	DBG_dump("_natd_hash: hash=", hash, hasher->hash_digest_len);
    );
#endif
}

/* Add NAT-Traversal VIDs (supported ones)
 * used when we are Initiator
 */
bool nat_traversal_add_vid(u_int8_t np, pb_stream *outs)
{
    bool r = TRUE;

    if (nat_traversal_support_port_floating)
    {
	u_int8_t last_np = nat_traversal_support_non_ike ?
				ISAKMP_NEXT_VID : np;

	if (r)
	    r = out_vendorid(ISAKMP_NEXT_VID, outs, VID_NATT_RFC);
	if (r)
	    r = out_vendorid(ISAKMP_NEXT_VID, outs, VID_NATT_IETF_03);
	if (r)
	    r = out_vendorid(ISAKMP_NEXT_VID, outs, VID_NATT_IETF_02);
	if (r)
	    r = out_vendorid(last_np, outs, VID_NATT_IETF_02_N);
    }
    if (nat_traversal_support_non_ike)
    {
	if (r)
	    r = out_vendorid(np, outs, VID_NATT_IETF_00);
    }
    return r;
}

u_int32_t nat_traversal_vid_to_method(unsigned short nat_t_vid)
{
    switch (nat_t_vid)
    {
    case VID_NATT_IETF_00:
	return LELEM(NAT_TRAVERSAL_IETF_00_01);
    case VID_NATT_IETF_02:
    case VID_NATT_IETF_02_N:
    case VID_NATT_IETF_03:
	return LELEM(NAT_TRAVERSAL_IETF_02_03);
    case VID_NATT_RFC:
	return LELEM(NAT_TRAVERSAL_RFC);
    }
    return 0;
}

void nat_traversal_natd_lookup(struct msg_digest *md)
{
    char hash[MAX_DIGEST_LEN];
    struct payload_digest *p;
    struct state *st = md->st;
    int i;

    if (!st || !md->iface || !st->st_oakley.hasher)
    {
	loglog(RC_LOG_SERIOUS, "NAT-Traversal: assert failed %s:%d"
		, __FILE__, __LINE__);
	return;
    }

    /** Count NAT-D **/
    for (p = md->chain[ISAKMP_NEXT_NATD_RFC], i=0; p != NULL; p = p->next, i++);

    /*
     * We need at least 2 NAT-D (1 for us, many for peer)
     */
    if (i < 2)
    {
	loglog(RC_LOG_SERIOUS,
	    "NAT-Traversal: Only %d NAT-D - Aborting NAT-Traversal negociation", i);
	st->nat_traversal = 0;
	return;
    }

    /*
     * First one with my IP & port
     */
    p = md->chain[ISAKMP_NEXT_NATD_RFC];
    _natd_hash(st->st_oakley.hasher, hash, st->st_icookie, st->st_rcookie,
	&(md->iface->addr), ntohs(st->st_connection->spd.this.host_port));

    if (!(pbs_left(&p->pbs) == st->st_oakley.hasher->hash_digest_len &&
	  memcmp(p->pbs.cur, hash, st->st_oakley.hasher->hash_digest_len) == 0))
    {
#ifdef NAT_D_DEBUG
	DBG(DBG_NATT,
	    DBG_log("NAT_TRAVERSAL_NAT_BHND_ME");
	    DBG_dump("expected NAT-D:", hash
	    		, st->st_oakley.hasher->hash_digest_len);
	    DBG_dump("received NAT-D:", p->pbs.cur, pbs_left(&p->pbs));
	)
#endif
	st->nat_traversal |= LELEM(NAT_TRAVERSAL_NAT_BHND_ME);
    }

    /*
     * The others with sender IP & port
     */
    _natd_hash(st->st_oakley.hasher, hash, st->st_icookie, st->st_rcookie,
		&(md->sender), ntohs(md->sender_port));
    for (p = p->next, i=0 ; p != NULL; p = p->next)
    {
	if (pbs_left(&p->pbs) == st->st_oakley.hasher->hash_digest_len &&
	    memcmp(p->pbs.cur, hash, st->st_oakley.hasher->hash_digest_len) == 0)
	{
	    i++;
	}
    }
    if (!i)
    {
#ifdef NAT_D_DEBUG
	DBG(DBG_NATT,
	    DBG_log("NAT_TRAVERSAL_NAT_BHND_PEER");
	    DBG_dump("expected NAT-D:", hash
			, st->st_oakley.hasher->hash_digest_len);
	    p = md->chain[ISAKMP_NEXT_NATD_RFC];
	    for (p = p->next, i=0 ; p != NULL; p = p->next)
	    {
		DBG_dump("received NAT-D:", p->pbs.cur, pbs_left(&p->pbs));
	    }
	)
#endif
	st->nat_traversal |= LELEM(NAT_TRAVERSAL_NAT_BHND_PEER);
    }
#ifdef FORCE_NAT_TRAVERSAL
    st->nat_traversal |= LELEM(NAT_TRAVERSAL_NAT_BHND_PEER);
    st->nat_traversal |= LELEM(NAT_TRAVERSAL_NAT_BHND_ME);
#endif
}

bool nat_traversal_add_natd(u_int8_t np, pb_stream *outs,
	struct msg_digest *md)
{
    char hash[MAX_DIGEST_LEN];
    struct state *st = md->st;

    if (!st || !st->st_oakley.hasher)
    {
	loglog(RC_LOG_SERIOUS, "NAT-Traversal: assert failed %s:%d"
			, __FILE__, __LINE__);
	return FALSE;
    }

    DBG(DBG_EMITTING,
	DBG_log("sending NATD payloads")
    )
	
    /*
     * First one with sender IP & port
     */
    _natd_hash(st->st_oakley.hasher, hash, st->st_icookie,
	is_zero_cookie(st->st_rcookie) ? md->hdr.isa_rcookie : st->st_rcookie,
	&(md->sender),
#ifdef FORCE_NAT_TRAVERSAL
	0
#else
	ntohs(md->sender_port)
#endif
    );
    if (!out_generic_raw((st->nat_traversal & NAT_T_WITH_RFC_VALUES
	? ISAKMP_NEXT_NATD_RFC : ISAKMP_NEXT_NATD_DRAFTS), &isakmp_nat_d, outs,
	hash, st->st_oakley.hasher->hash_digest_len, "NAT-D"))
    {
	return FALSE;
    }

    /*
     * Second one with my IP & port
     */
    _natd_hash(st->st_oakley.hasher, hash, st->st_icookie,
	is_zero_cookie(st->st_rcookie) ? md->hdr.isa_rcookie : st->st_rcookie,
	&(md->iface->addr),
#ifdef FORCE_NAT_TRAVERSAL
	0
#else
	ntohs(st->st_connection->spd.this.host_port)
#endif
    );
    return (out_generic_raw(np, &isakmp_nat_d, outs,
	hash, st->st_oakley.hasher->hash_digest_len, "NAT-D"));
}

/*
 * nat_traversal_natoa_lookup()
 * 
 * Look for NAT-OA in message
 */
void nat_traversal_natoa_lookup(struct msg_digest *md)
{
    struct payload_digest *p;
    struct state *st = md->st;
    int i;
    ip_address ip;

    if (!st || !md->iface)
    {
	loglog(RC_LOG_SERIOUS, "NAT-Traversal: assert failed %s:%d"
		, __FILE__, __LINE__);
	return;
    }

    /* Initialize NAT-OA */
    anyaddr(AF_INET, &st->nat_oa);

    /* Count NAT-OA **/
    for (p = md->chain[ISAKMP_NEXT_NATOA_RFC], i=0; p != NULL; p = p->next, i++);

    DBG(DBG_NATT,
	DBG_log("NAT-Traversal: received %d NAT-OA.", i)
    )

    if (i == 0)
	return;

    if (!(st->nat_traversal & LELEM(NAT_TRAVERSAL_NAT_BHND_PEER)))
    {
	loglog(RC_LOG_SERIOUS, "NAT-Traversal: received %d NAT-OA. "
			"ignored because peer is not NATed", i);
	return;
    }

    if (i > 1)
    {
	loglog(RC_LOG_SERIOUS, "NAT-Traversal: received %d NAT-OA. "
		"using first, ignoring others", i);
    }

    /* Take first */
    p = md->chain[ISAKMP_NEXT_NATOA_RFC];

    DBG(DBG_PARSING,
	DBG_dump("NAT-OA:", p->pbs.start, pbs_room(&p->pbs));
    );

    switch (p->payload.nat_oa.isanoa_idtype)
    {
    case ID_IPV4_ADDR:
	if (pbs_left(&p->pbs) == sizeof(struct in_addr))
	{
	    initaddr(p->pbs.cur, pbs_left(&p->pbs), AF_INET, &ip);
	}
	else
	{
	    loglog(RC_LOG_SERIOUS, "NAT-Traversal: received IPv4 NAT-OA "
			"with invalid IP size (%d)", (int)pbs_left(&p->pbs));
	    return;
	}
	break;
    case ID_IPV6_ADDR:
	if (pbs_left(&p->pbs) == sizeof(struct in6_addr))
	{
	    initaddr(p->pbs.cur, pbs_left(&p->pbs), AF_INET6, &ip);
	}
	else
	{
	    loglog(RC_LOG_SERIOUS, "NAT-Traversal: received IPv6 NAT-OA "
			"with invalid IP size (%d)", (int)pbs_left(&p->pbs));
	    return;
	}
	break;
    default:
	loglog(RC_LOG_SERIOUS, "NAT-Traversal: "
			"invalid ID Type (%d) in NAT-OA - ignored",
			p->payload.nat_oa.isanoa_idtype);
	    return;
    }

    DBG(DBG_NATT,
	{
	    char ip_t[ADDRTOT_BUF];
	    addrtot(&ip, 0, ip_t, sizeof(ip_t));
	
	    DBG_log("received NAT-OA: %s", ip_t);
	}
    )

    if (isanyaddr(&ip))
	loglog(RC_LOG_SERIOUS, "NAT-Traversal: received %%any NAT-OA...");
    else
	st->nat_oa = ip;
}

bool nat_traversal_add_natoa(u_int8_t np, pb_stream *outs,
	struct state *st)
{
    struct isakmp_nat_oa natoa;
    pb_stream pbs;
    unsigned char ip_val[sizeof(struct in6_addr)];
    size_t ip_len = 0;
    ip_address *ip;

    if ((!st) || (!st->st_connection))
    {
	loglog(RC_LOG_SERIOUS, "NAT-Traversal: assert failed %s:%d"
			, __FILE__, __LINE__);
	return FALSE;
    }
    ip = &(st->st_connection->spd.this.host_addr);

    memset(&natoa, 0, sizeof(natoa));
    natoa.isanoa_np = np;

    switch (addrtypeof(ip))
    {
    case AF_INET:
	ip_len = sizeof(ip->u.v4.sin_addr.s_addr);
	memcpy(ip_val, &ip->u.v4.sin_addr.s_addr, ip_len);
	natoa.isanoa_idtype = ID_IPV4_ADDR;
	break;
    case AF_INET6:
	ip_len = sizeof(ip->u.v6.sin6_addr.s6_addr);
	memcpy(ip_val, &ip->u.v6.sin6_addr.s6_addr, ip_len);
	natoa.isanoa_idtype = ID_IPV6_ADDR;
	break;
    default:
	loglog(RC_LOG_SERIOUS, "NAT-Traversal: "
			"invalid addrtypeof()=%d", addrtypeof(ip));
	return FALSE;
    }

    if (!out_struct(&natoa, &isakmp_nat_oa, outs, &pbs))
	return FALSE;

    if (!out_raw(ip_val, ip_len, &pbs, "NAT-OA"))
	return FALSE;

    DBG(DBG_NATT,
	DBG_dump("NAT-OA (S):", ip_val, ip_len)
    )

    close_output_pbs(&pbs);
    return TRUE;
}

void nat_traversal_show_result (u_int32_t nt, u_int16_t sport)
{
    const char *mth = NULL, *rslt = NULL;

    switch (nt & NAT_TRAVERSAL_METHOD)
    {
    case LELEM(NAT_TRAVERSAL_IETF_00_01):
	mth = natt_type_bitnames[0];
	break;
    case LELEM(NAT_TRAVERSAL_IETF_02_03):
	mth = natt_type_bitnames[1];
	break;
    case LELEM(NAT_TRAVERSAL_RFC):
	mth = natt_type_bitnames[2];
	break;
    }
    
    switch (nt & NAT_T_DETECTED)
    {
    case 0:
	rslt = "no NAT detected";
	break;
    case LELEM(NAT_TRAVERSAL_NAT_BHND_ME):
	rslt = "i am NATed";
	break;
    case LELEM(NAT_TRAVERSAL_NAT_BHND_PEER):
	rslt = "peer is NATed";
	break;
    case LELEM(NAT_TRAVERSAL_NAT_BHND_ME) | LELEM(NAT_TRAVERSAL_NAT_BHND_PEER):
	rslt = "both are NATed";
	break;
    }

    loglog(RC_LOG_SERIOUS,
	"NAT-Traversal: Result using %s: %s",
	mth ? mth : "unknown method",
	rslt ? rslt : "unknown result"
    );

    if ((nt & LELEM(NAT_TRAVERSAL_NAT_BHND_PEER))
    &&	(sport == IKE_UDP_PORT)
    &&	((nt & NAT_T_WITH_PORT_FLOATING)==0))
    {
	loglog(RC_LOG_SERIOUS,
		"Warning: peer is NATed but source port is still udp/%d. "
		"Ipsec-passthrough NAT device suspected -- NAT-T may not work.",
		IKE_UDP_PORT
	);
    }
}

int nat_traversal_espinudp_socket (int sk, u_int32_t type)
{
    int r = setsockopt(sk, SOL_UDP, UDP_ESPINUDP, &type, sizeof(type));

    if (r < 0 && errno == ENOPROTOOPT)
    {
	loglog(RC_LOG_SERIOUS,
		"NAT-Traversal: ESPINUDP(%d) not supported by kernel -- "
		"NAT-T disabled", type);
	disable_nat_traversal(type);
    }
    return r;
}

void nat_traversal_new_ka_event (void)
{
    if (_ka_evt)
	return;  /* event already scheduled */

    event_schedule(EVENT_NAT_T_KEEPALIVE, _kap, NULL);
    _ka_evt = 1;
}

static void nat_traversal_send_ka (struct state *st)
{
    static unsigned char ka_payload = 0xff;
    chunk_t sav;

    DBG(DBG_NATT,
	DBG_log("ka_event: send NAT-KA to %s:%d",
		ip_str(&st->st_connection->spd.that.host_addr),
		st->st_connection->spd.that.host_port);
    )

    /* save state chunk */
    setchunk(sav, st->st_tpacket.ptr, st->st_tpacket.len);

    /* send keep alive */
    setchunk(st->st_tpacket, &ka_payload, 1);
    send_packet(st, "NAT-T Keep Alive");

    /* restore state chunk */
    setchunk(st->st_tpacket, sav.ptr, sav.len);
}

/**
 * Find ISAKMP States with NAT-T and send keep-alive
 */
static void nat_traversal_ka_event_state (struct state *st, void *data)
{
    unsigned int *_kap_st = (unsigned int *)data;
    const struct connection *c = st->st_connection;

    if (!c)
	return;

    if ((st->st_state == STATE_MAIN_R3 || st->st_state == STATE_MAIN_I4)
    &&	(st->nat_traversal & NAT_T_DETECTED)
    &&	((st->nat_traversal & LELEM(NAT_TRAVERSAL_NAT_BHND_ME)) || _force_ka))
    {
	/*
	 * - ISAKMP established
	 * - NAT-Traversal detected
	 * - NAT-KeepAlive needed (we are NATed)
	 */
	if (c->newest_isakmp_sa != st->st_serialno)
	{
	    /*
	     * if newest is also valid, ignore this one, we will only use
	     * newest.
	     */
	    struct state *st_newest;

	    st_newest = state_with_serialno(c->newest_isakmp_sa);
	    if (st_newest
	    && (st_newest->st_state == STATE_MAIN_R3 || st_newest->st_state == STATE_MAIN_I4)
	    && (st_newest->nat_traversal & NAT_T_DETECTED)
	    && ((st_newest->nat_traversal & LELEM(NAT_TRAVERSAL_NAT_BHND_ME)) || _force_ka))
	    {
		return;
	    }
	}
	set_cur_state(st);
	nat_traversal_send_ka(st);
	reset_cur_state();
	(*_kap_st)++;
    }
}

void nat_traversal_ka_event (void)
{
    unsigned int _kap_st = 0;

    _ka_evt = 0;  /* ready to be reschedule */

    for_each_state((void *)nat_traversal_ka_event_state, &_kap_st);

    /* if there are still states who needs Keep-Alive, schedule new event */
    if (_kap_st)
	nat_traversal_new_ka_event();
}

struct _new_mapp_nfo {
	ip_address addr;
	u_int16_t sport, dport;
};

static void nat_traversal_find_new_mapp_state (struct state *st, void *data)
{
    struct connection *c = st->st_connection;
    struct _new_mapp_nfo *nfo = (struct _new_mapp_nfo *)data;

    if (c != NULL
    && sameaddr(&c->spd.that.host_addr, &(nfo->addr))
    &&	c->spd.that.host_port == nfo->sport)
    {

	/* change host port */
	c->spd.that.host_port = nfo->dport;

	if (IS_IPSEC_SA_ESTABLISHED(st->st_state)
	||  IS_ONLY_INBOUND_IPSEC_SA_ESTABLISHED(st->st_state))
	{
	    if (!update_ipsec_sa(st))
	    {
		/*
		 * If ipsec update failed, restore old port or we'll
		 * not be able to update anymore.
		 */
		c->spd.that.host_port = nfo->sport;
	    }
	}
    }
}

static int nat_traversal_new_mapping(const ip_address *src, u_int16_t sport,
	const ip_address *dst, u_int16_t dport)
{
    char srca[ADDRTOT_BUF], dsta[ADDRTOT_BUF];
    struct _new_mapp_nfo nfo;

    addrtot(src, 0, srca, ADDRTOT_BUF);
    addrtot(dst, 0, dsta, ADDRTOT_BUF);

    if (!sameaddr(src, dst))
    {
	loglog(RC_LOG_SERIOUS, "nat_traversal_new_mapping: "
		"address change currently not supported [%s:%d,%s:%d]",
		srca, sport, dsta, dport);
	return -1;
    }

    if (sport == dport)
    {
	/* no change */
	return 0;
    }

    DBG_log("NAT-T: new mapping %s:%d/%d)", srca, sport, dport);

    nfo.addr = *src;
    nfo.sport = sport;
    nfo.dport = dport;

    for_each_state((void *)nat_traversal_find_new_mapp_state, &nfo);

    return 0;
}

void nat_traversal_change_port_lookup(struct msg_digest *md, struct state *st)
{
    struct connection *c = st ? st->st_connection : NULL;
    struct iface *i = NULL;

    if ((st == NULL) || (c == NULL))
	return;

    if (md)
    {
	/*
	 * If source port has changed, update (including other states and
	 * established kernel SA)
	 */
	if (c->spd.that.host_port != md->sender_port)
	{
	    nat_traversal_new_mapping(&c->spd.that.host_addr, c->spd.that.host_port,
			&c->spd.that.host_addr, md->sender_port);
	}

	/*
	 * If interface type has changed, update local port (500/4500)
	 */
	if ((c->spd.this.host_port == NAT_T_IKE_FLOAT_PORT && !md->iface->ike_float)
	||  (c->spd.this.host_port != NAT_T_IKE_FLOAT_PORT &&  md->iface->ike_float))
	{
	    c->spd.this.host_port = (md->iface->ike_float)
		? NAT_T_IKE_FLOAT_PORT : pluto_port;

	    DBG(DBG_NATT,
		DBG_log("NAT-T: updating local port to %d", c->spd.this.host_port);
	    );
	}
    }

    /*
     * If we're initiator and NAT-T (with port floating) is detected, we
     * need to change port (MAIN_I3 or QUICK_I1)
     */
    if ((st->st_state == STATE_MAIN_I3 || st->st_state == STATE_QUICK_I1)
    &&	(st->nat_traversal & NAT_T_WITH_PORT_FLOATING)
    &&	(st->nat_traversal & NAT_T_DETECTED)
    &&	(c->spd.this.host_port != NAT_T_IKE_FLOAT_PORT))
    {
	DBG(DBG_NATT,
	    DBG_log("NAT-T: floating to port %d", NAT_T_IKE_FLOAT_PORT);
	)
	c->spd.this.host_port = NAT_T_IKE_FLOAT_PORT;
	c->spd.that.host_port = NAT_T_IKE_FLOAT_PORT;
	/*
	 * Also update pending connections or they will be deleted if uniqueids
	 * option is set.
	 */
	update_pending(st, st);
    }

    /*
     * Find valid interface according to local port (500/4500)
     */
    if ((c->spd.this.host_port == NAT_T_IKE_FLOAT_PORT && !c->interface->ike_float)
    ||  (c->spd.this.host_port != NAT_T_IKE_FLOAT_PORT &&  c->interface->ike_float))
    {
	for (i = interfaces; i !=  NULL; i = i->next)
	{
	    if (sameaddr(&c->interface->addr, &i->addr)
	    && i->ike_float != c->interface->ike_float)
	    {
		DBG(DBG_NATT,
		    DBG_log("NAT-T: using interface %s:%d", i->rname,
			i->ike_float ? NAT_T_IKE_FLOAT_PORT : pluto_port);
		)
		c->interface = i;
		break;
	    }
	}
    }
}

struct _new_klips_mapp_nfo {
	struct sadb_sa *sa;
	ip_address src, dst;
	u_int16_t sport, dport;
};

static void nat_t_new_klips_mapp (struct state *st, void *data)
{
    struct connection *c = st->st_connection;
    struct _new_klips_mapp_nfo *nfo = (struct _new_klips_mapp_nfo *)data;

    if (c != NULL && st->st_esp.present
    &&	sameaddr(&c->spd.that.host_addr, &(nfo->src))
    &&  st->st_esp.our_spi == nfo->sa->sadb_sa_spi)
    {
	nat_traversal_new_mapping(&c->spd.that.host_addr, c->spd.that.host_port,
				  &(nfo->dst), nfo->dport);
    }
}

void process_pfkey_nat_t_new_mapping(
	struct sadb_msg *msg __attribute__ ((unused)),
	struct sadb_ext *extensions[SADB_EXT_MAX + 1])
{
    struct _new_klips_mapp_nfo nfo;
    struct sadb_address *srcx = (void *) extensions[SADB_EXT_ADDRESS_SRC];
    struct sadb_address *dstx = (void *) extensions[SADB_EXT_ADDRESS_DST];
    struct sockaddr *srca, *dsta;
    err_t ugh = NULL;

    nfo.sa = (void *) extensions[SADB_EXT_SA];

    if (!nfo.sa || !srcx || !dstx)
    {
	plog("SADB_X_NAT_T_NEW_MAPPING message from KLIPS malformed: "
		"got NULL params");
	return;
    }

    srca = ((struct sockaddr *)(void *)&srcx[1]);
    dsta = ((struct sockaddr *)(void *)&dstx[1]);

    if (srca->sa_family != AF_INET || dsta->sa_family != AF_INET)
    {
	ugh = "only AF_INET supported";
    }
    else
    {
	char text_said[SATOT_BUF];
	char _srca[ADDRTOT_BUF], _dsta[ADDRTOT_BUF];
	ip_said said;

	initaddr((const void *) &((const struct sockaddr_in *)srca)->sin_addr,
			sizeof(((const struct sockaddr_in *)srca)->sin_addr),
			srca->sa_family, &(nfo.src));
	nfo.sport = ntohs(((const struct sockaddr_in *)srca)->sin_port);
	initaddr((const void *) &((const struct sockaddr_in *)dsta)->sin_addr,
			sizeof(((const struct sockaddr_in *)dsta)->sin_addr),
			dsta->sa_family, &(nfo.dst));
	nfo.dport = ntohs(((const struct sockaddr_in *)dsta)->sin_port);

	DBG(DBG_NATT,
	    initsaid(&nfo.src, nfo.sa->sadb_sa_spi, SA_ESP, &said);
	    satot(&said, 0, text_said, SATOT_BUF);
	    addrtot(&nfo.src, 0, _srca, ADDRTOT_BUF);
	    addrtot(&nfo.dst, 0, _dsta, ADDRTOT_BUF);
	    DBG_log("new klips mapping %s %s:%d %s:%d",
			text_said, _srca, nfo.sport, _dsta, nfo.dport);
	)

	for_each_state((void *)nat_t_new_klips_mapp, &nfo);
    }

    if (ugh != NULL)
	plog("SADB_X_NAT_T_NEW_MAPPING message from KLIPS malformed: %s", ugh);
}