//==========================================================================
//
//      src/sys/netinet6/in6.c
//
//==========================================================================
// ####BSDCOPYRIGHTBEGIN####                                    
// -------------------------------------------                  
// This file is part of eCos, the Embedded Configurable Operating System.
//
// Portions of this software may have been derived from FreeBSD 
// or other sources, and if so are covered by the appropriate copyright
// and license included herein.                                 
//
// Portions created by the Free Software Foundation are         
// Copyright (C) 2002 Free Software Foundation, Inc.            
// -------------------------------------------                  
// ####BSDCOPYRIGHTEND####                                      
//==========================================================================

/*	$KAME: in6.c,v 1.256 2001/12/24 10:39:29 jinmei Exp $	*/

/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT 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 PROJECT 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.
 */

/*
 * Copyright (c) 1982, 1986, 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 *	@(#)in.c	8.2 (Berkeley) 11/15/93
 */

#include <sys/param.h>
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sockio.h>

#include <net/if.h>
#include <net/if_types.h>
#include <net/route.h>
#include <net/if_dl.h>

#include <netinet/in.h>
#include <netinet/in_var.h>
#ifdef __NetBSD__
#include <net/if_ether.h>
#else
#include <netinet/if_ether.h>
#endif
#ifndef SCOPEDROUTING
#if defined(__OpenBSD__) || (defined(__bsdi__) && _BSDI_VERSION >= 199802) || (defined(__FreeBSD__) && __FreeBSD__ >= 3)
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#endif
#endif

#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/nd6.h>
#include <netinet6/mld6_var.h>
#include <netinet6/ip6_mroute.h>
#include <netinet6/in6_ifattach.h>
#include <netinet6/scope6_var.h>
#ifndef SCOPEDROUTING
#if defined(__NetBSD__) || (defined(__bsdi__) && _BSDI_VERSION < 199802) || defined(__FreeBSD__)
#include <netinet6/in6_pcb.h>
#endif
#endif

#ifdef MIP6
#include <netinet6/mip6.h>
#endif /* MIP6 */

/*
 * Definitions of some costant IP6 addresses.
 */
const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
const struct in6_addr in6addr_nodelocal_allnodes =
	IN6ADDR_NODELOCAL_ALLNODES_INIT;
const struct in6_addr in6addr_linklocal_allnodes =
	IN6ADDR_LINKLOCAL_ALLNODES_INIT;
const struct in6_addr in6addr_linklocal_allrouters =
	IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;

const struct in6_addr in6mask0 = IN6MASK0;
const struct in6_addr in6mask32 = IN6MASK32;
const struct in6_addr in6mask64 = IN6MASK64;
const struct in6_addr in6mask96 = IN6MASK96;
const struct in6_addr in6mask128 = IN6MASK128;

const struct sockaddr_in6 sa6_any = {sizeof(sa6_any), AF_INET6,
				     0, 0, IN6ADDR_ANY_INIT, 0};

#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3)
static int in6_lifaddr_ioctl __P((struct socket *, u_long, caddr_t,
	struct ifnet *, struct proc *));
#else
static int in6_lifaddr_ioctl __P((struct socket *, u_long, caddr_t,
	struct ifnet *));
#endif
static int in6_ifinit __P((struct ifnet *, struct in6_ifaddr *,
			   struct sockaddr_in6 *, int));
static void in6_unlink_ifa __P((struct in6_ifaddr *, struct ifnet *));

#if defined(__FreeBSD__) && __FreeBSD__ >= 3
struct in6_multihead in6_multihead;	/* XXX BSS initialization */
#else
/*
 * This structure is used to keep track of in6_multi chains which belong to
 * deleted interface addresses.
 */
static LIST_HEAD(, multi6_kludge) in6_mk; /* XXX BSS initialization */

struct multi6_kludge {
	LIST_ENTRY(multi6_kludge) mk_entry;
	struct ifnet *mk_ifp;
	struct in6_multihead mk_head;
};
#endif

#ifdef MEASURE_PERFORMANCE
static void in6h_delifa __P((struct in6_ifaddr *));
static void in6h_addhash __P((struct in6hash *));
static void in6h_delhash __P((struct in6hash *));
#endif

/*
 * Subroutine for in6_ifaddloop() and in6_ifremloop().
 * This routine does actual work.
 */
static void
in6_ifloop_request(int cmd, struct ifaddr *ifa)
{
	struct sockaddr_in6 all1_sa;
	struct rtentry *nrt = NULL;
	int e;
	
	bzero(&all1_sa, sizeof(all1_sa));
	all1_sa.sin6_family = AF_INET6;
	all1_sa.sin6_len = sizeof(struct sockaddr_in6);
	all1_sa.sin6_addr = in6mask128;

	/*
	 * We specify the address itself as the gateway, and set the
	 * RTF_LLINFO flag, so that the corresponding host route would have
	 * the flag, and thus applications that assume traditional behavior
	 * would be happy.  Note that we assume the caller of the function
	 * (probably implicitly) set nd6_rtrequest() to ifa->ifa_rtrequest,
	 * which changes the outgoing interface to the loopback interface.
	 */
	e = rtrequest(cmd, ifa->ifa_addr, ifa->ifa_addr,
		      (struct sockaddr *)&all1_sa,
		      RTF_UP|RTF_HOST|RTF_LLINFO, &nrt);
	if (e != 0) {
		log(LOG_ERR, "in6_ifloop_request: "
		    "%s operation failed for %s (errno=%d)\n",
		    cmd == RTM_ADD ? "ADD" : "DELETE",
		    ip6_sprintf(&((struct in6_ifaddr *)ifa)->ia_addr.sin6_addr),
		    e);
	}

	/*
	 * Make sure rt_ifa be equal to IFA, the second argument of the
	 * function.
	 * We need this because when we refer to rt_ifa->ia6_flags in
	 * ip6_input, we assume that the rt_ifa points to the address instead
	 * of the loopback address.
	 */
	if (cmd == RTM_ADD && nrt && ifa != nrt->rt_ifa) {
		IFAFREE(nrt->rt_ifa);
		IFAREF(ifa);
		nrt->rt_ifa = ifa;
	}

	/*
	 * Report the addition/removal of the address to the routing socket.
	 * XXX: since we called rtinit for a p2p interface with a destination,
	 *      we end up reporting twice in such a case.  Should we rather
	 *      omit the second report?
	 */
	if (nrt) {
		rt_newaddrmsg(cmd, ifa, e, nrt);
		if (cmd == RTM_DELETE) {
			if (nrt->rt_refcnt <= 0) {
				/* XXX: we should free the entry ourselves. */
				nrt->rt_refcnt++;
				rtfree(nrt);
			}
		} else {
			/* the cmd must be RTM_ADD here */
			nrt->rt_refcnt--;
		}
	}
}

/*
 * Add ownaddr as loopback rtentry.  We previously add the route only if
 * necessary (ex. on a p2p link).  However, since we now manage addresses
 * separately from prefixes, we should always add the route.  We can't
 * rely on the cloning mechanism from the corresponding interface route
 * any more.
 */
static void
in6_ifaddloop(struct ifaddr *ifa)
{
	struct rtentry *rt;

	/* If there is no loopback entry, allocate one. */
	rt = rtalloc1(ifa->ifa_addr, 0
#ifdef __FreeBSD__
		      , 0
#endif /* __FreeBSD__ */
		);
	if (rt == NULL || (rt->rt_flags & RTF_HOST) == 0 ||
	    (rt->rt_ifp->if_flags & IFF_LOOPBACK) == 0)
		in6_ifloop_request(RTM_ADD, ifa);
	if (rt)
		rt->rt_refcnt--;
}

/*
 * Remove loopback rtentry of ownaddr generated by in6_ifaddloop(),
 * if it exists.
 */
static void
in6_ifremloop(struct ifaddr *ifa)
{
	struct in6_ifaddr *ia;
	struct rtentry *rt;
	int ia_count = 0;

	/*
	 * Some of BSD variants do not remove cloned routes
	 * from an interface direct route, when removing the direct route
	 * (see comments in net/net_osdep.h).  Even for variants that do remove
	 * cloned routes, they could fail to remove the cloned routes when
	 * we handle multple addresses that share a common prefix.
	 * So, we should remove the route corresponding to the deleted address
	 * regardless of the result of in6_is_ifloop_auto().
	 */

	/*
	 * Delete the entry only if exact one ifa exists.  More than one ifa
	 * can exist if we assign a same single address to multiple
	 * (probably p2p) interfaces.
	 * XXX: we should avoid such a configuration in IPv6...
	 */
	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
		if (IN6_ARE_ADDR_EQUAL(IFA_IN6(ifa), &ia->ia_addr.sin6_addr)) {
			ia_count++;
			if (ia_count > 1)
				break;
		}
	}

	if (ia_count == 1) {
		/*
		 * Before deleting, check if a corresponding loopbacked host
		 * route surely exists.  With this check, we can avoid to
		 * delete an interface direct route whose destination is same
		 * as the address being removed.  This can happen when remofing
		 * a subnet-router anycast address on an interface attahced
		 * to a shared medium.
		 */
		rt = rtalloc1(ifa->ifa_addr, 0
#ifdef __FreeBSD__
			      , 0
#endif /* __FreeBSD__ */
			);
		if (rt != NULL && (rt->rt_flags & RTF_HOST) != 0 &&
		    (rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) {
			rt->rt_refcnt--;
			in6_ifloop_request(RTM_DELETE, ifa);
		}
	}
}

int
in6_ifindex2scopeid(idx)
	int idx;
{
	struct ifnet *ifp;
	struct ifaddr *ifa;
	struct sockaddr_in6 *sin6;

	if (idx < 0 || if_index < idx)
		return -1;
#if defined(__FreeBSD__) && __FreeBSD__ >= 5
	ifp = ifnet_byindex(idx);
#else
	ifp = ifindex2ifnet[idx];
#endif
	if (!ifp)
		return -1;

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#elif defined(__FreeBSD__) && __FreeBSD__ >= 4
	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
#else
	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
#endif
	{
		if (ifa->ifa_addr->sa_family != AF_INET6)
			continue;
		sin6 = (struct sockaddr_in6 *)ifa->ifa_addr;
		if (IN6_IS_ADDR_SITELOCAL(&sin6->sin6_addr))
			return sin6->sin6_scope_id & 0xffff;
	}

	return -1;
}

int
in6_mask2len(mask, lim0)
	struct in6_addr *mask;
	u_char *lim0;
{
	int x = 0, y;
	u_char *lim = lim0, *p;

	if (lim0 == NULL ||
	    lim0 - (u_char *)mask > sizeof(*mask)) /* ignore the scope_id part */
		lim = (u_char *)mask + sizeof(*mask);
	for (p = (u_char *)mask; p < lim; x++, p++) {
		if (*p != 0xff)
			break;
	}
	y = 0;
	if (p < lim) {
		for (y = 0; y < 8; y++) {
			if ((*p & (0x80 >> y)) == 0)
				break;
		}
	}

	/*
	 * when the limit pointer is given, do a stricter check on the
	 * remaining bits.
	 */
	if (p < lim) {
		if (y != 0 && (*p & (0x00ff >> y)) != 0)
			return(-1);
		for (p = p + 1; p < lim; p++)
			if (*p != 0)
				return(-1);
	}
	
	return x * 8 + y;
}

#define ifa2ia6(ifa)	((struct in6_ifaddr *)(ifa))
#define ia62ifa(ia6)	(&((ia6)->ia_ifa))

int
#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3)
in6_control(so, cmd, data, ifp, p)
	struct	socket *so;
	u_long cmd;
	caddr_t	data;
	struct ifnet *ifp;
	struct proc *p;
#else
in6_control(so, cmd, data, ifp)
	struct	socket *so;
	u_long cmd;
	caddr_t	data;
	struct ifnet *ifp;
#endif
{
	struct	in6_ifreq *ifr = (struct in6_ifreq *)data;
	struct	in6_ifaddr *ia = NULL;
	struct	in6_aliasreq *ifra = (struct in6_aliasreq *)data;
	struct sockaddr_in6 *sa6;
#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
	time_t time_second = (time_t)time.tv_sec;
#endif

	switch (cmd) {
	case SIOCGETSGCNT_IN6:
	case SIOCGETMIFCNT_IN6:
		return (mrt6_ioctl(cmd, data));
	}

	switch(cmd) {
	case SIOCAADDRCTL_POLICY:
	case SIOCDADDRCTL_POLICY:
		return(in6_src_ioctl(cmd, data));
	}

#ifdef MIP6
	switch (cmd) {
	case SIOCENABLEMN:
	case SIOCENABLEHA:
		return(mip6_ioctl(cmd, data));
	case SIOCGBC:
		return(mip6_ioctl(cmd, data));
	}
#endif /* MIP6 */

	if (ifp == NULL)
		return(EOPNOTSUPP);

	switch (cmd) {
	case SIOCSNDFLUSH_IN6:
	case SIOCSPFXFLUSH_IN6:
	case SIOCSRTRFLUSH_IN6:
	case SIOCSDEFIFACE_IN6:
	case SIOCSIFINFO_FLAGS:
		/* fall through */
	case OSIOCGIFINFO_IN6:
	case SIOCGIFINFO_IN6:
	case SIOCGDRLST_IN6:
	case SIOCGPRLST_IN6:
	case SIOCGNBRINFO_IN6:
	case SIOCGDEFIFACE_IN6:
		return(nd6_ioctl(cmd, data, ifp));
	}

	switch (cmd) {
	case SIOCSIFPREFIX_IN6:
	case SIOCDIFPREFIX_IN6:
	case SIOCAIFPREFIX_IN6:
	case SIOCCIFPREFIX_IN6:
	case SIOCSGIFPREFIX_IN6:
	case SIOCGIFPREFIX_IN6:
		log(LOG_NOTICE,
		    "prefix ioctls are now invalidated. "
		    "please use ifconfig.\n");
		return(EOPNOTSUPP);
	}

	switch (cmd) {
	case SIOCSSCOPE6:
		return(scope6_set(ifp, ifr->ifr_ifru.ifru_scope_id));
	case SIOCGSCOPE6:
		return(scope6_get(ifp, ifr->ifr_ifru.ifru_scope_id));
	case SIOCGSCOPE6DEF:
		return(scope6_get_default(ifr->ifr_ifru.ifru_scope_id));
	}

	switch (cmd) {
	case SIOCALIFADDR:
	case SIOCDLIFADDR:
		/* fall through */
	case SIOCGLIFADDR:
#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3)
		return in6_lifaddr_ioctl(so, cmd, data, ifp, p);
#else
		return in6_lifaddr_ioctl(so, cmd, data, ifp);
#endif
	}

	/*
	 * Find address for this interface, if it exists.
	 *
	 * In netinet code, we have checked ifra_addr in SIOCSIF*ADDR operation
	 * only, and used the first interface address as the target of other
	 * operations (without checking ifra_addr).  This was because netinet
	 * code/API assumed at most 1 interface address per interface.
	 * Since IPv6 allows a node to assign multiple addresses
	 * on a single interface, we almost always look and check the
	 * presence of ifra_addr, and reject invalid ones here.
	 * It also decreases duplicated code among SIOC*_IN6 operations.
	 */
	switch (cmd) {
	case SIOCAIFADDR_IN6:
	case SIOCSIFPHYADDR_IN6:
		sa6 = &ifra->ifra_addr;
		break;
	case SIOCSIFADDR_IN6:
	case SIOCGIFADDR_IN6:
	case SIOCSIFDSTADDR_IN6:
	case SIOCSIFNETMASK_IN6:
	case SIOCGIFDSTADDR_IN6:
	case SIOCGIFNETMASK_IN6:
	case SIOCDIFADDR_IN6:
	case SIOCGIFPSRCADDR_IN6:
	case SIOCGIFPDSTADDR_IN6:
	case SIOCGIFAFLAG_IN6:
	case SIOCSNDFLUSH_IN6:
	case SIOCSPFXFLUSH_IN6:
	case SIOCSRTRFLUSH_IN6:
	case SIOCGIFALIFETIME_IN6:
	case SIOCSIFALIFETIME_IN6:
	case SIOCGIFSTAT_IN6:
	case SIOCGIFSTAT_ICMP6:
		sa6 = &ifr->ifr_addr;
		break;
	default:
		sa6 = NULL;
		break;
	}
	if (sa6 && sa6->sin6_family == AF_INET6) {
		if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) {
			if (sa6->sin6_addr.s6_addr16[1] == 0) {
				/* link ID is not embedded by the user */
				sa6->sin6_addr.s6_addr16[1] =
					htons(ifp->if_index);
			} else if (sa6->sin6_addr.s6_addr16[1] !=
				    htons(ifp->if_index)) {
				return(EINVAL);	/* link ID contradicts */
			}
			if (sa6->sin6_scope_id) {
				if (sa6->sin6_scope_id !=
				    (u_int32_t)ifp->if_index)
					return(EINVAL);
				sa6->sin6_scope_id = 0; /* XXX: good way? */
			}
		}
		ia = in6ifa_ifpwithaddr(ifp, &sa6->sin6_addr);
	} else
		ia = NULL;

	switch (cmd) {
	case SIOCSIFADDR_IN6:
	case SIOCSIFDSTADDR_IN6:
	case SIOCSIFNETMASK_IN6:
		/*
		 * Since IPv6 allows a node to assign multiple addresses
		 * on a single interface, SIOCSIFxxx ioctls are deprecated.
		 */
		return(EINVAL);

	case SIOCDIFADDR_IN6:
		/*
		 * for IPv4, we look for existing in_ifaddr here to allow
		 * "ifconfig if0 delete" to remove the first IPv4 address on
		 * the interface.  For IPv6, as the spec allows multiple
		 * interface address from the day one, we consider "remove the
		 * first one" semantics to be not preferable.
		 */
		if (ia == NULL)
			return(EADDRNOTAVAIL);
		/* FALLTHROUGH */
	case SIOCAIFADDR_IN6:
		/*
		 * We always require users to specify a valid IPv6 address for
		 * the corresponding operation.
		 */
		if (ifra->ifra_addr.sin6_family != AF_INET6 ||
		    ifra->ifra_addr.sin6_len != sizeof(struct sockaddr_in6))
			return(EAFNOSUPPORT);

		break;

	case SIOCGIFADDR_IN6:
		/* This interface is basically deprecated. use SIOCGIFCONF. */
		/* fall through */
	case SIOCGIFAFLAG_IN6:
	case SIOCGIFNETMASK_IN6:
	case SIOCGIFDSTADDR_IN6:
	case SIOCGIFALIFETIME_IN6:
		/* must think again about its semantics */
		if (ia == NULL)
			return(EADDRNOTAVAIL);
		break;
	case SIOCSIFALIFETIME_IN6:
	    {
		struct in6_addrlifetime *lt;

		if (ia == NULL)
			return(EADDRNOTAVAIL);
		/* sanity for overflow - beware unsigned */
		lt = &ifr->ifr_ifru.ifru_lifetime;
		if (lt->ia6t_vltime != ND6_INFINITE_LIFETIME
		 && lt->ia6t_vltime + time_second < time_second) {
			return EINVAL;
		}
		if (lt->ia6t_pltime != ND6_INFINITE_LIFETIME
		 && lt->ia6t_pltime + time_second < time_second) {
			return EINVAL;
		}
		break;
	    }
	}

	switch (cmd) {

	case SIOCGIFADDR_IN6:
		ifr->ifr_addr = ia->ia_addr;
		break;

	case SIOCGIFDSTADDR_IN6:
		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
			return(EINVAL);
		/*
		 * XXX: should we check if ifa_dstaddr is NULL and return
		 * an error?
		 */
		ifr->ifr_dstaddr = ia->ia_dstaddr;
		break;

	case SIOCGIFNETMASK_IN6:
		ifr->ifr_addr = ia->ia_prefixmask;
		break;

	case SIOCGIFAFLAG_IN6:
		ifr->ifr_ifru.ifru_flags6 = ia->ia6_flags;
		break;

	case SIOCGIFSTAT_IN6:
		if (ifp == NULL)
			return EINVAL;
		if (in6_ifstat == NULL || ifp->if_index >= in6_ifstatmax
		 || in6_ifstat[ifp->if_index] == NULL) {
			/* return EAFNOSUPPORT? */
			bzero(&ifr->ifr_ifru.ifru_stat,
				sizeof(ifr->ifr_ifru.ifru_stat));
		} else
			ifr->ifr_ifru.ifru_stat = *in6_ifstat[ifp->if_index];
		break;

	case SIOCGIFSTAT_ICMP6:
		if (ifp == NULL)
			return EINVAL;
		if (icmp6_ifstat == NULL || ifp->if_index >= icmp6_ifstatmax ||
		    icmp6_ifstat[ifp->if_index] == NULL) {
			/* return EAFNOSUPPORT? */
			bzero(&ifr->ifr_ifru.ifru_stat,
				sizeof(ifr->ifr_ifru.ifru_icmp6stat));
		} else
			ifr->ifr_ifru.ifru_icmp6stat =
				*icmp6_ifstat[ifp->if_index];
		break;

	case SIOCGIFALIFETIME_IN6:
		ifr->ifr_ifru.ifru_lifetime = ia->ia6_lifetime;
		if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
			time_t maxexpire;
			struct in6_addrlifetime *retlt = &ifr->ifr_ifru.ifru_lifetime;

			/*
			 * XXX: adjust expiration time assuming time_t is
			 * signed.
			 */
			maxexpire = (-1) &
				~(1 << ((sizeof(maxexpire) * 8) - 1));
			if (ia->ia6_lifetime.ia6t_vltime < 
			    maxexpire - ia->ia6_updatetime) {
				retlt->ia6t_expire = ia->ia6_updatetime +
					ia->ia6_lifetime.ia6t_vltime;
			} else
				retlt->ia6t_expire = maxexpire;
		}
		if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
			time_t maxexpire;
			struct in6_addrlifetime *retlt = &ifr->ifr_ifru.ifru_lifetime;

			/*
			 * XXX: adjust expiration time assuming time_t is
			 * signed.
			 */
			maxexpire = (-1) &
				~(1 << ((sizeof(maxexpire) * 8) - 1));
			if (ia->ia6_lifetime.ia6t_pltime < 
			    maxexpire - ia->ia6_updatetime) {
				retlt->ia6t_preferred = ia->ia6_updatetime +
					ia->ia6_lifetime.ia6t_pltime;
			} else
				retlt->ia6t_preferred = maxexpire;
		}
		break;

	case SIOCSIFALIFETIME_IN6:
		ia->ia6_lifetime = ifr->ifr_ifru.ifru_lifetime;
		/* for sanity */
		if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
			ia->ia6_lifetime.ia6t_expire =
				time_second + ia->ia6_lifetime.ia6t_vltime;
		} else
			ia->ia6_lifetime.ia6t_expire = 0;
		if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
			ia->ia6_lifetime.ia6t_preferred =
				time_second + ia->ia6_lifetime.ia6t_pltime;
		} else
			ia->ia6_lifetime.ia6t_preferred = 0;
		break;

	case SIOCAIFADDR_IN6:
	{
		int i, error = 0;
		struct nd_prefix pr0, *pr;

		/*
		 * first, make or update the interface address structure,
		 * and link it to the list.
		 */
		if ((error = in6_update_ifa(ifp, ifra, ia)) != 0)
			return(error);
		if ((ia = in6ifa_ifpwithaddr(ifp, &ifra->ifra_addr.sin6_addr))
		    == NULL) {
		    	/*
			 * this can happen when the user specify the 0 valid
			 * lifetime.
			 */
			break;
		}

		/*
		 * then, make the prefix on-link on the interface.
		 * XXX: we'd rather create the prefix before the address, but
		 * we need at least one address to install the corresponding
		 * interface route, so we configure the address first.
		 */

		/*
		 * convert mask to prefix length (prefixmask has already
		 * been validated in in6_update_ifa().
		 */
		bzero(&pr0, sizeof(pr0));
		pr0.ndpr_ifp = ifp;
		pr0.ndpr_plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
					     NULL);
		if (pr0.ndpr_plen == 128)
			break;	/* we don't need to install a host route. */
		pr0.ndpr_prefix = ifra->ifra_addr;
		pr0.ndpr_mask = ifra->ifra_prefixmask.sin6_addr;
		/* apply the mask for safety. */
		for (i = 0; i < 4; i++) {
			pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
				ifra->ifra_prefixmask.sin6_addr.s6_addr32[i];
		}
		/*
		 * XXX: since we don't have an API to set prefix (not address)
		 * lifetimes, we just use the same lifetimes as addresses.
		 * The (temporarily) installed lifetimes can be overridden by
		 * later advertised RAs (when accept_rtadv is non 0), which is
		 * an intended behavior.
		 */
		pr0.ndpr_raf_onlink = 1; /* should be configurable? */
		pr0.ndpr_raf_auto =
			((ifra->ifra_flags & IN6_IFF_AUTOCONF) != 0);
		pr0.ndpr_vltime = ifra->ifra_lifetime.ia6t_vltime;
		pr0.ndpr_pltime = ifra->ifra_lifetime.ia6t_pltime;

		/* add the prefix if there's one. */
		if ((pr = nd6_prefix_lookup(&pr0)) == NULL) {
			/*
			 * nd6_prelist_add will install the corresponding
			 * interface route.
			 */
			if ((error = nd6_prelist_add(&pr0, NULL, &pr)) != 0)
				return(error);
			if (pr == NULL) {
				log(LOG_ERR, "nd6_prelist_add succeeded but "
				    "no prefix\n");
				return(EINVAL); /* XXX panic here? */
			}
		}
		if ((ia->ia6_flags & IN6_IFF_AUTOCONF) &&
		    ia->ia6_ndpr == NULL) { /* new autoconfed addr */
			ia->ia6_ndpr = pr;
			pr->ndpr_refcnt++;

			/*
			 * If this is the first autoconf address from
			 * the prefix, create a temporary address
			 * as well (when specified).
			 */
			if (ip6_use_tempaddr && pr->ndpr_refcnt == 1) {
				int e;
				if ((e = in6_tmpifadd(ia, 1)) != 0) {
					log(LOG_NOTICE, "in6_control: failed "
					    "to create a temporary address, "
					    "errno=%d\n",
					    e);
				}
			}
		}

		/*
		 * this might affect the status of autoconfigured addresses,
		 * that is, this address might make other addresses detached.
		 */
		pfxlist_onlink_check();

		break;
	}

	case SIOCDIFADDR_IN6:
	{
		int i = 0, purgeprefix = 0;
		struct nd_prefix pr0, *pr = NULL;

		/*
		 * If the address being deleted is the only one that owns
		 * the corresponding prefix, expire the prefix as well.
		 * XXX: theoretically, we don't have to worry about such
		 * relationship, since we separate the address management
		 * and the prefix management.  We do this, however, to provide
		 * as much backward compatibility as possible in terms of
		 * the ioctl operation.
		 */
		bzero(&pr0, sizeof(pr0));
		pr0.ndpr_ifp = ifp;
		pr0.ndpr_plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr,
					     NULL);
		if (pr0.ndpr_plen == 128)
			goto purgeaddr;
		pr0.ndpr_prefix = ia->ia_addr;
		pr0.ndpr_mask = ia->ia_prefixmask.sin6_addr;
		for (i = 0; i < 4; i++) {
			pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &=
				ia->ia_prefixmask.sin6_addr.s6_addr32[i];
		}
		/*
		 * The logic of the following condition is a bit complicated.
		 * We expire the prefix when
		 * 1. the address obeys autoconfiguration and it is the
		 *    only owner of the associated prefix, or
		 * 2. the address does not obey autoconf and there is no
		 *    other owner of the prefix.
		 */
		if ((pr = nd6_prefix_lookup(&pr0)) != NULL &&
		    (((ia->ia6_flags & IN6_IFF_AUTOCONF) != 0 &&
		      pr->ndpr_refcnt == 1) ||
		     ((ia->ia6_flags & IN6_IFF_AUTOCONF) == 0 &&
		      pr->ndpr_refcnt == 0)))
			purgeprefix = 1;

	  purgeaddr:
		in6_purgeaddr(&ia->ia_ifa);
		if (pr && purgeprefix)
			prelist_remove(pr);
		break;
	}

	default:
		if (ifp == NULL || ifp->if_ioctl == 0)
			return(EOPNOTSUPP);
		return((*ifp->if_ioctl)(ifp, cmd, data));
	}

	return(0);
}

#ifdef __ECOS
extern void _show_ifp(struct ifnet *ifp);
#endif

/*
 * Update parameters of an IPv6 interface address.
 * If necessary, a new entry is created and linked into address chains.
 * This function is separated from in6_control().
 * XXX: should this be performed under splnet()?
 */
static int
_in6_update_ifa(struct ifnet *ifp, struct in6_aliasreq *ifra,
                struct in6_ifaddr *ia)
{
	int error = 0, hostIsNew = 0, plen = -1;
	struct in6_ifaddr *oia;
#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	struct ifaddr *ifa;
#endif
	struct sockaddr_in6 dst6;
	struct in6_addrlifetime *lt;
	struct in6_multi_mship *imm;
#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
	time_t time_second = (time_t)time.tv_sec;
#endif
#ifdef MEASURE_PERFORMANCE
	int new_ifa = 0;
#endif
	struct rtentry *rt;

	/* Validate parameters */
	if (ifp == NULL || ifra == NULL) /* this maybe redundant */
		return(EINVAL);

	/*
	 * The destination address for a p2p link must have a family
	 * of AF_UNSPEC or AF_INET6.
	 */
	if ((ifp->if_flags & IFF_POINTOPOINT) != 0 &&
	    ifra->ifra_dstaddr.sin6_family != AF_INET6 &&
	    ifra->ifra_dstaddr.sin6_family != AF_UNSPEC)
		return(EAFNOSUPPORT);
	/*
	 * validate ifra_prefixmask.  don't check sin6_family, netmask
	 * does not carry fields other than sin6_len.
	 */
	if (ifra->ifra_prefixmask.sin6_len > sizeof(struct sockaddr_in6))
		return(EINVAL);
	/*
	 * Because the IPv6 address architecture is classless, we require
	 * users to specify a (non 0) prefix length (mask) for a new address.
	 * We also require the prefix (when specified) mask is valid, and thus
	 * reject a non-consecutive mask.
	 */
	if (ia == NULL && ifra->ifra_prefixmask.sin6_len == 0)
		return(EINVAL);
	if (ifra->ifra_prefixmask.sin6_len != 0) {
		plen = in6_mask2len(&ifra->ifra_prefixmask.sin6_addr,
				    (u_char *)&ifra->ifra_prefixmask +
				    ifra->ifra_prefixmask.sin6_len);
		if (plen <= 0)
			return(EINVAL);
	}
	else {
		/*
		 * In this case, ia must not be NULL.  We just use its prefix
		 * length.
		 */
		plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL);
	}
	/*
	 * If the destination address on a p2p interface is specified,
	 * and the address is a scoped one, validate/set the scope
	 * zone identifier.
	 */
	dst6 = ifra->ifra_dstaddr;
	if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) &&
	    (dst6.sin6_family == AF_INET6)) {
		int64_t zoneid;

#ifndef SCOPEDROUTING
		if ((error = in6_recoverscope(&dst6,
					      &ifra->ifra_dstaddr.sin6_addr,
					      ifp)) != 0)
			return(error);
#endif
		if ((zoneid = in6_addr2zoneid(ifp, &dst6.sin6_addr)) < 0)
			return(EINVAL);
		if (dst6.sin6_scope_id == 0) /* user omit to specify the ID. */
			dst6.sin6_scope_id = zoneid;
		else if (dst6.sin6_scope_id != zoneid)
			return(EINVAL); /* scope ID mismatch. */
		if ((error = in6_embedscope(&dst6.sin6_addr, &dst6)) != 0)
			return(error);
#ifndef SCOPEDROUTING
		dst6.sin6_scope_id = 0; /* XXX */
#endif
	}
	/*
	 * The destination address can be specified only for a p2p or a
	 * loopback interface.  If specified, the corresponding prefix length
	 * must be 128.
	 */
	if (ifra->ifra_dstaddr.sin6_family == AF_INET6) {
#ifdef FORCE_P2PPLEN
		int i;
#endif

		if ((ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)) == 0) {
			/* XXX: noisy message */
			log(LOG_INFO, "in6_update_ifa: a destination can be "
			    "specified for a p2p or a loopback IF only\n");
			return(EINVAL);
		}
		if (plen != 128) {
			log(LOG_INFO, "in6_update_ifa: prefixlen should be "
			    "128 when dstaddr is specified\n");
#ifdef FORCE_P2PPLEN
			/*
			 * To be compatible with old configurations,
			 * such as ifconfig gif0 inet6 2001::1 2001::2
			 * prefixlen 126, we override the specified
			 * prefixmask as if the prefix length was 128.
			 */
			ifra->ifra_prefixmask.sin6_len
				= sizeof(struct sockaddr_in6); 
			for (i = 0; i < 4; i++)
				ifra->ifra_prefixmask.sin6_addr.s6_addr32[i] =
					0xffffffff;
			plen = 128;
#else
			return(EINVAL);
#endif
		}
	}
	/* lifetime consistency check */
	lt = &ifra->ifra_lifetime;
	if (lt->ia6t_pltime > lt->ia6t_vltime)
		return(EINVAL);
	if (lt->ia6t_vltime == 0) {
		/*
		 * the following log might be noisy, but this is a typical
		 * configuration mistake or a tool's bug.
		 */
		log(LOG_INFO,
		    "in6_update_ifa: valid lifetime is 0 for %s\n",
		    ip6_sprintf(&ifra->ifra_addr.sin6_addr));

		if (ia == NULL)
			return(0); /* there's nothing to do */
	}

	/*
	 * If this is a new address, allocate a new ifaddr and link it
	 * into chains.
	 */
	if (ia == NULL) {
		hostIsNew = 1;
		/*
		 * When in6_update_ifa() is called in a process of a received
		 * RA, it is called under an interrupt context.  So, we should
		 * call malloc with M_NOWAIT.
		 */
		ia = (struct in6_ifaddr *)
			malloc(sizeof(*ia), M_IFADDR, M_NOWAIT);
		if (ia == NULL)
			return (ENOBUFS);
		bzero((caddr_t)ia, sizeof(*ia));
		LIST_INIT(&ia->ia6_memberships);
		/* Initialize the address and masks, and put time stamp */
		ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
		ia->ia_addr.sin6_family = AF_INET6;
		ia->ia_addr.sin6_len = sizeof(ia->ia_addr);
		ia->ia6_createtime = ia->ia6_updatetime = time_second;
		if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) != 0) {
			/*
			 * XXX: some functions expect that ifa_dstaddr is not
			 * NULL for p2p interfaces.
			 */
			ia->ia_ifa.ifa_dstaddr
				= (struct sockaddr *)&ia->ia_dstaddr;
		} else {
			ia->ia_ifa.ifa_dstaddr = NULL;
		}
		ia->ia_ifa.ifa_netmask
			= (struct sockaddr *)&ia->ia_prefixmask;

		ia->ia_ifp = ifp;
		if ((oia = in6_ifaddr) != NULL) {
			for ( ; oia->ia_next; oia = oia->ia_next)
				continue;
			oia->ia_next = ia;
		} else
			in6_ifaddr = ia;
#ifdef __NetBSD__
		/* gain a refcnt for the link from in6_ifaddr */
		IFAREF(&ia->ia_ifa);
#endif

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
		if ((ifa = ifp->if_addrlist) != NULL) {
			for ( ; ifa->ifa_next; ifa = ifa->ifa_next)
				continue;
			ifa->ifa_next = ia62ifa(ia);
		} else
			ifp->if_addrlist = ia62ifa(ia);
#else
		TAILQ_INSERT_TAIL(&ifp->if_addrlist, &ia->ia_ifa,
				  ifa_list);
                log_(LOG_ADDR) {
                    diag_printf("%s.%d - After inserting %p into list %p\n", 
                                __FUNCTION__, __LINE__,
                                &ia->ia_ifa, &ifp->if_addrlist);
                    _show_ifp(ifp);
                }
#endif
#ifdef __NetBSD__
		/* gain another refcnt for the link from if_addrlist */
		IFAREF(&ia->ia_ifa);
#endif

#ifdef MEASURE_PERFORMANCE
		new_ifa = 1;
#endif
	}

	/* set prefix mask */
	if (ifra->ifra_prefixmask.sin6_len) {
		/*
		 * We prohibit changing the prefix length of an existing
		 * address, because
		 * + such an operation should be rare in IPv6, and
		 * + the operation would confuse prefix management.
		 */
		if (ia->ia_prefixmask.sin6_len &&
		    in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL) != plen) {
			log(LOG_INFO, "in6_update_ifa: the prefix length of an"
			    " existing (%s) address should not be changed\n",
			    ip6_sprintf(&ia->ia_addr.sin6_addr));
			error = EINVAL;
			goto unlink;
		}
		ia->ia_prefixmask = ifra->ifra_prefixmask;
	}

	/*
	 * If a new destination address is specified, scrub the old one and
	 * install the new destination.  Note that the interface must be
	 * p2p or loopback (see the check above.) 
	 */
	if (dst6.sin6_family == AF_INET6 &&
	    !IN6_ARE_ADDR_EQUAL(&dst6.sin6_addr,
				&ia->ia_dstaddr.sin6_addr)) {
		int e;

		if ((ia->ia_flags & IFA_ROUTE) != 0 &&
		    (e = rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST))
		    != 0) {
			log(LOG_ERR, "in6_update_ifa: failed to remove "
			    "a route to the old destination: %s\n",
			    ip6_sprintf(&ia->ia_addr.sin6_addr));
			/* proceed anyway... */
		}
		else
			ia->ia_flags &= ~IFA_ROUTE;
		ia->ia_dstaddr = dst6;
	}

	/*
	 * Set lifetimes.  We do not refer to ia6t_expire and ia6t_preferred
	 * to see if the address is deprecated or invalidated, but initialize
	 * these members for applications.
	 */
	ia->ia6_lifetime = ifra->ifra_lifetime;
	if (ia->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
		ia->ia6_lifetime.ia6t_expire =
			time_second + ia->ia6_lifetime.ia6t_vltime;
	} else
		ia->ia6_lifetime.ia6t_expire = 0;
	if (ia->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
		ia->ia6_lifetime.ia6t_preferred =
			time_second + ia->ia6_lifetime.ia6t_pltime;
	} else
		ia->ia6_lifetime.ia6t_preferred = 0;

	/* reset the interface and routing table appropriately. */
	if ((error = in6_ifinit(ifp, ia, &ifra->ifra_addr, hostIsNew)) != 0)
		goto unlink;

	/*
	 * Make the address tentative before joining multicast addresses,
	 * so that corresponding MLD responses would not have a tentative
	 * source address.
	 */
	ia->ia6_flags = ifra->ifra_flags;
	ia->ia6_flags &= ~IN6_IFF_DUPLICATED;	/* safety */
#ifdef MIP6
	if (hostIsNew && in6if_do_dad(ifp) && mip6_ifa_need_dad(ia))
#else /* MIP6 */
	if (hostIsNew && in6if_do_dad(ifp))
#endif /* MIP6 */
		ia->ia6_flags |= IN6_IFF_TENTATIVE;

	/*
	 * Beyond this point, we should call in6_purgeaddr upon an error,
	 * not just go to unlink. 
	 */

	if ((ifp->if_flags & IFF_MULTICAST) != 0) {
		struct sockaddr_in6 mltaddr, mltmask;

		if (hostIsNew) {
			/*
			 * join solicited multicast addr for new host id
			 */
			struct in6_addr llsol;
			bzero(&llsol, sizeof(struct in6_addr));
			llsol.s6_addr16[0] = htons(0xff02);
			llsol.s6_addr16[1] = htons(ifp->if_index);
			llsol.s6_addr32[1] = 0;
			llsol.s6_addr32[2] = htonl(1);
			llsol.s6_addr32[3] =
				ifra->ifra_addr.sin6_addr.s6_addr32[3];
			llsol.s6_addr8[12] = 0xff;
			imm = in6_joingroup(ifp, &llsol, &error);
			if (imm) {
				LIST_INSERT_HEAD(&ia->ia6_memberships, imm,
				    i6mm_chain);
			} else {
				log(LOG_ERR,
				    "in6_update_ifa: addmulti failed for "
				    "%s on %s (errno=%d)\n",
				    ip6_sprintf(&llsol), 
				    if_name(ifp), error);
				goto cleanup;
			}
		}

		bzero(&mltmask, sizeof(mltmask));
		mltmask.sin6_len = sizeof(struct sockaddr_in6);
		mltmask.sin6_family = AF_INET6;
		mltmask.sin6_addr = in6mask32;

		/*
		 * join link-local all-nodes address
		 */
		bzero(&mltaddr, sizeof(mltaddr));
		mltaddr.sin6_len = sizeof(struct sockaddr_in6);
		mltaddr.sin6_family = AF_INET6;
		mltaddr.sin6_addr = in6addr_linklocal_allnodes;
		mltaddr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);

#ifdef __FreeBSD__
		rt = rtalloc1((struct sockaddr *)&mltaddr, 0, 0UL);
#else
		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
#endif
		if (rt) {
			/* 32bit came from "mltmask" */
			if (memcmp(&mltaddr.sin6_addr,
			    &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr,
			    32 / 8)) {
				RTFREE(rt);
				rt = NULL;
			}
		}
		if (!rt) {
#if (defined(__bsdi__) && _BSDI_VERSION >= 199802)
			struct rt_addrinfo info;

			bzero(&info, sizeof(info));
			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
			info.rti_info[RTAX_GATEWAY] =
				(struct sockaddr *)&ia->ia_addr;
			info.rti_info[RTAX_NETMASK] =
				(struct sockaddr *)&mltmask;
			info.rti_info[RTAX_IFA] =
				(struct sockaddr *)&ia->ia_addr;
			/* XXX: we need RTF_CLONING to fake nd6_rtrequest */
			info.rti_flags = RTF_UP | RTF_CLONING;
			error = rtrequest1(RTM_ADD, &info, NULL);
#else
			error = rtrequest(RTM_ADD,
					  (struct sockaddr *)&mltaddr,
					  (struct sockaddr *)&ia->ia_addr,
					  (struct sockaddr *)&mltmask,
					  RTF_UP | RTF_CLONING,
					  (struct rtentry **)0);
#endif
			if (error)
				goto cleanup;
		} else {
			RTFREE(rt);
		}
		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error);
		if (imm) {
			LIST_INSERT_HEAD(&ia->ia6_memberships, imm,
			    i6mm_chain);
		} else {
			log(LOG_WARNING,
			    "in6_update_ifa: addmulti failed for "
			    "%s on %s (errno=%d)\n",
			    ip6_sprintf(&mltaddr.sin6_addr), 
			    if_name(ifp), error);
			goto cleanup;
		}

		/*
		 * join node information group address
		 */
#ifdef __FreeBSD__
#define hostnamelen	strlen(hostname)
#endif
		if (in6_nigroup(ifp, hostname, hostnamelen, &mltaddr.sin6_addr)
		    == 0) {
			imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error);
			if (imm) {
				LIST_INSERT_HEAD(&ia->ia6_memberships, imm,
				    i6mm_chain);
			} else {
				log(LOG_WARNING, "in6_update_ifa: "
				    "addmulti failed for "
				    "%s on %s (errno=%d)\n",
				    ip6_sprintf(&mltaddr.sin6_addr), 
				    if_name(ifp), error);
				/* XXX not very fatal, go on... */
			}
		}
#ifdef __FreeBSD__
#undef hostnamelen
#endif

		/*
		 * join interface-local all-nodes address, on loopback.
		 * (ff01::1%ifN, and ff01::%ifN/32)
		 */
		mltaddr.sin6_addr = in6addr_nodelocal_allnodes;
		mltaddr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
#ifdef __FreeBSD__
		rt = rtalloc1((struct sockaddr *)&mltaddr, 0, 0UL);
#else
		rt = rtalloc1((struct sockaddr *)&mltaddr, 0);
#endif
		if (rt) {
			/* 32bit came from "mltmask" */
			if (memcmp(&mltaddr.sin6_addr,
			    &((struct sockaddr_in6 *)rt_key(rt))->sin6_addr,
			    32 / 8)) {
				RTFREE(rt);
				rt = NULL;
			}
		}
		if (!rt) {
#if (defined(__bsdi__) && _BSDI_VERSION >= 199802)
			struct rt_addrinfo info;

			bzero(&info, sizeof(info));
			info.rti_info[RTAX_DST] = (struct sockaddr *)&mltaddr;
			info.rti_info[RTAX_GATEWAY] =
				(struct sockaddr *)&ia->ia_addr;
			info.rti_info[RTAX_NETMASK] =
				(struct sockaddr *)&mltmask;
			info.rti_info[RTAX_IFA] =
				(struct sockaddr *)&ia->ia_addr;
			info.rti_flags = RTF_UP | RTF_CLONING;
			error = rtrequest1(RTM_ADD, &info, NULL);
#else
			error = rtrequest(RTM_ADD,
					  (struct sockaddr *)&mltaddr,
					  (struct sockaddr *)&ia->ia_addr,
					  (struct sockaddr *)&mltmask,
					  RTF_UP | RTF_CLONING,
					  (struct rtentry **)0);
#endif
			if (error)
				goto cleanup;
		} else {
			RTFREE(rt);
		}

		imm = in6_joingroup(ifp, &mltaddr.sin6_addr, &error);
		if (imm) {
			LIST_INSERT_HEAD(&ia->ia6_memberships, imm,
			    i6mm_chain);
		} else {
			log(LOG_WARNING, "in6_update_ifa: "
			    "addmulti failed for %s on %s "
			    "(errno=%d)\n",
			    ip6_sprintf(&mltaddr.sin6_addr), 
			    if_name(ifp), error);
			goto cleanup;
		}
	}

#ifdef MEASURE_PERFORMANCE
	{
		int s = splnet();
		if (new_ifa)
			in6h_addifa(ia);
		else
			in6h_rebuild(0);
		splx(s);
	}
#endif

	/*
	 * make sure to initialize ND6 information.  this is to workaround
	 * issues with interfaces with IPv6 addresses, which have never brought
	 * up.  We are assuming that it is safe to nd6_ifattach multiple times.
	 */
	nd6_ifattach(ifp);

	/*
	 * Perform DAD, if needed.
	 * XXX It may be of use, if we can administratively
	 * disable DAD.
	 */
#ifdef MIP6
	if (hostIsNew && in6if_do_dad(ifp) && mip6_ifa_need_dad(ia) &&
	    (ifra->ifra_flags & IN6_IFF_NODAD) == 0)
#else /* MIP6 */
	if (hostIsNew && in6if_do_dad(ifp) &&
	    (ifra->ifra_flags & IN6_IFF_NODAD) == 0)
#endif /* MIP6 */
	{
		nd6_dad_start((struct ifaddr *)ia, NULL);
	}

	return(error);

  unlink:
	/*
	 * XXX: if a change of an existing address failed, keep the entry
	 * anyway.
	 */
	if (hostIsNew)
		in6_unlink_ifa(ia, ifp);
	return(error);

  cleanup:
	in6_purgeaddr(&ia->ia_ifa);
	return error;
}

void
in6_purgeaddr(ifa)
	struct ifaddr *ifa;
{
	struct ifnet *ifp = ifa->ifa_ifp;
	struct in6_ifaddr *ia = (struct in6_ifaddr *) ifa;
	struct in6_multi_mship *imm;

	/* stop DAD processing */
	nd6_dad_stop(ifa);

	/*
	 * delete route to the destination of the address being purged.
	 * The interface must be p2p or loopback in this case.
	 */
	if ((ia->ia_flags & IFA_ROUTE) != 0 && ia->ia_dstaddr.sin6_len != 0) {
		int e;

		if ((e = rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST))
		    != 0) {
			log(LOG_ERR, "in6_purgeaddr: failed to remove "
			    "a route to the p2p destination: %s on %s, "
			    "errno=%d\n",
			    ip6_sprintf(&ia->ia_addr.sin6_addr), if_name(ifp),
			    e);
			/* proceed anyway... */
		}
		else
			ia->ia_flags &= ~IFA_ROUTE;
	}

	/* Remove ownaddr's loopback rtentry, if it exists. */
	in6_ifremloop(&(ia->ia_ifa));

	/*
	 * leave from multicast groups we have joined for the interface
	 */
	while ((imm = ia->ia6_memberships.lh_first) != NULL) {
		LIST_REMOVE(imm, i6mm_chain);
		in6_leavegroup(imm);
	}

	in6_unlink_ifa(ia, ifp);
}

int
in6_update_ifa(ifp, ifra, ia)
	struct ifnet *ifp;
	struct in6_aliasreq *ifra;
	struct in6_ifaddr *ia;
{
    int res;
    int s = splnet();
//    extern int irq_level;
//    if (irq_level) {
//        diag_printf("%s - called from IRQ!\n", __FUNCTION__);
//    }
    res = _in6_update_ifa(ifp, ifra, ia);
    splx(s);
    return res;
}

static void
in6_unlink_ifa(ia, ifp)
	struct in6_ifaddr *ia;
	struct ifnet *ifp;
{
	struct in6_ifaddr *oia;
#ifdef __NetBSD__
	int	s = splsoftnet();
#else
	int	s = splnet();
#endif

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	struct ifaddr *ifa;
#endif

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	if ((ifa = ifp->if_addrlist) == ia62ifa(ia))
		ifp->if_addrlist = ifa->ifa_next;
	else {
		while (ifa->ifa_next &&
		       (ifa->ifa_next != ia62ifa(ia)))
			ifa = ifa->ifa_next;
		if (ifa->ifa_next)
			ifa->ifa_next = ia62ifa(ia)->ifa_next;
		else {
			/* search failed */
			printf("Couldn't unlink in6_ifaddr from ifp\n");
		}
	}
#else
	TAILQ_REMOVE(&ifp->if_addrlist, &ia->ia_ifa, ifa_list);
        log_(LOG_ADDR) {
            diag_printf("%s.%d - After removing %p into list %p\n", 
                        __FUNCTION__, __LINE__,
                        &ia->ia_ifa, &ifp->if_addrlist);
            _show_ifp(ifp);
        }
#endif
#ifdef __NetBSD__
	/* release a refcnt for the link from if_addrlist */
	IFAFREE(&ia->ia_ifa);
#endif

	oia = ia;
	if (oia == (ia = in6_ifaddr))
		in6_ifaddr = ia->ia_next;
	else {
		while (ia->ia_next && (ia->ia_next != oia))
			ia = ia->ia_next;
		if (ia->ia_next)
			ia->ia_next = oia->ia_next;
		else {
			/* search failed */
			printf("Couldn't unlink in6_ifaddr from in6_ifaddr\n");
		}
	}

#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
	if (oia->ia6_multiaddrs.lh_first != NULL) {
#ifdef __NetBSD__
		/*
		 * XXX thorpej@netbsd.org -- if the interface is going
		 * XXX away, don't save the multicast entries, delete them!
		 */
		if (oia->ia_ifa.ifa_ifp->if_output == if_nulloutput) {
			struct in6_multi *in6m;

			while ((in6m =
			    LIST_FIRST(&oia->ia6_multiaddrs)) != NULL)
				in6_delmulti(in6m);
		} else
			in6_savemkludge(oia);
#else
		in6_savemkludge(oia);
#endif
	}
#endif

#ifdef MEASURE_PERFORMANCE
	in6h_delifa(oia);
#endif

	/*
	 * When an autoconfigured address is being removed, release the
	 * reference to the base prefix.  Also, since the release might
	 * affect the status of other (detached) addresses, call
	 * pfxlist_onlink_check().
	 */
	if ((oia->ia6_flags & IN6_IFF_AUTOCONF) != 0) {
		if (oia->ia6_ndpr == NULL) {
			log(LOG_NOTICE, "in6_unlink_ifa: autoconf'ed address "
			    "%p has no prefix\n", oia);
		} else {
			oia->ia6_ndpr->ndpr_refcnt--;
			oia->ia6_flags &= ~IN6_IFF_AUTOCONF;
			oia->ia6_ndpr = NULL;
		}

		pfxlist_onlink_check();
	}

	/*
	 * release another refcnt for the link from in6_ifaddr.
	 * Note that we should decrement the refcnt at least once for all *BSD.
	 */
	IFAFREE(&oia->ia_ifa);

	splx(s);
}

void
in6_purgeif(ifp)
	struct ifnet *ifp;
{
	struct ifaddr *ifa, *nifa;

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	for (ifa = ifp->if_addrlist; ifa; ifa = nifa)
#else
	for (ifa = TAILQ_FIRST(&ifp->if_addrlist); ifa != NULL; ifa = nifa)
#endif
	{
#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
		nifa = ifa->ifa_next;
#else
		nifa = TAILQ_NEXT(ifa, ifa_list);
#endif
		if (ifa->ifa_addr->sa_family != AF_INET6)
			continue;
		in6_purgeaddr(ifa);
	}

#if !(defined(__bsdi__) && _BSDI_VERSION >= 199802)
	in6_ifdetach(ifp);
#endif
}

/*
 * SIOC[GAD]LIFADDR.
 *	SIOCGLIFADDR: get first address. (?)
 *	SIOCGLIFADDR with IFLR_PREFIX:
 *		get first address that matches the specified prefix.
 *	SIOCALIFADDR: add the specified address.
 *	SIOCALIFADDR with IFLR_PREFIX:
 *		add the specified prefix, filling hostid part from
 *		the first link-local address.  prefixlen must be <= 64.
 *	SIOCDLIFADDR: delete the specified address.
 *	SIOCDLIFADDR with IFLR_PREFIX:
 *		delete the first address that matches the specified prefix.
 * return values:
 *	EINVAL on invalid parameters
 *	EADDRNOTAVAIL on prefix match failed/specified address not found
 *	other values may be returned from in6_ioctl()
 *
 * NOTE: SIOCALIFADDR(with IFLR_PREFIX set) allows prefixlen less than 64.
 * this is to accomodate address naming scheme other than RFC2374,
 * in the future.
 * RFC2373 defines interface id to be 64bit, but it allows non-RFC2374
 * address encoding scheme. (see figure on page 8)
 */
static int
#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3)
in6_lifaddr_ioctl(so, cmd, data, ifp, p)
	struct socket *so;
	u_long cmd;
	caddr_t	data;
	struct ifnet *ifp;
	struct proc *p;
#else
in6_lifaddr_ioctl(so, cmd, data, ifp)
	struct socket *so;
	u_long cmd;
	caddr_t	data;
	struct ifnet *ifp;
#endif
{
	struct if_laddrreq *iflr = (struct if_laddrreq *)data;
	struct ifaddr *ifa;
	struct sockaddr *sa;
	int64_t zoneid;

	/* sanity checks */
	if (!data || !ifp) {
		panic("invalid argument to in6_lifaddr_ioctl");
		/* NOTREACHED */
	}

	switch (cmd) {
	case SIOCGLIFADDR:
		/* address must be specified on GET with IFLR_PREFIX */
		if ((iflr->flags & IFLR_PREFIX) == 0)
			break;
		/* FALLTHROUGH */
	case SIOCALIFADDR:
	case SIOCDLIFADDR:
		/* address must be specified on ADD and DELETE */
		sa = (struct sockaddr *)&iflr->addr;
		if (sa->sa_family != AF_INET6)
			return EINVAL;
		if (sa->sa_len != sizeof(struct sockaddr_in6))
			return EINVAL;
		/* XXX need improvement */
		sa = (struct sockaddr *)&iflr->dstaddr;
		if (sa->sa_family && sa->sa_family != AF_INET6)
			return EINVAL;
		if (sa->sa_len && sa->sa_len != sizeof(struct sockaddr_in6))
			return EINVAL;
		break;
	default: /* shouldn't happen */
#if 0
		panic("invalid cmd to in6_lifaddr_ioctl");
		/* NOTREACHED */
#else
		return EOPNOTSUPP;
#endif
	}
	if (sizeof(struct in6_addr) * 8 < iflr->prefixlen)
		return EINVAL;

	switch (cmd) {
	case SIOCALIFADDR:
	    {
		struct in6_aliasreq ifra;
		struct in6_addr *hostid = NULL;
		int prefixlen;

		if ((iflr->flags & IFLR_PREFIX) != 0) {
			struct sockaddr_in6 *sin6;

			/*
			 * hostid is to fill in the hostid part of the
			 * address.  hostid points to the first link-local
			 * address attached to the interface.
			 */
			ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0);
			if (!ifa)
				return EADDRNOTAVAIL;
			hostid = IFA_IN6(ifa);

		 	/* prefixlen must be <= 64. */
			if (64 < iflr->prefixlen)
				return EINVAL;
			prefixlen = iflr->prefixlen;

			/* hostid part must be zero. */
			sin6 = (struct sockaddr_in6 *)&iflr->addr;
			if (sin6->sin6_addr.s6_addr32[2] != 0
			 || sin6->sin6_addr.s6_addr32[3] != 0) {
				return EINVAL;
			}
		} else
			prefixlen = iflr->prefixlen;

		/* copy args to in6_aliasreq, perform ioctl(SIOCAIFADDR_IN6). */
		bzero(&ifra, sizeof(ifra));
		bcopy(iflr->iflr_name, ifra.ifra_name,
			sizeof(ifra.ifra_name));

		bcopy(&iflr->addr, &ifra.ifra_addr,
			((struct sockaddr *)&iflr->addr)->sa_len);
		if (hostid) {
			/* fill in hostid part */
			ifra.ifra_addr.sin6_addr.s6_addr32[2] =
				hostid->s6_addr32[2];
			ifra.ifra_addr.sin6_addr.s6_addr32[3] =
				hostid->s6_addr32[3];
		}

		if (((struct sockaddr *)&iflr->dstaddr)->sa_family) { /* XXX */
			bcopy(&iflr->dstaddr, &ifra.ifra_dstaddr,
				((struct sockaddr *)&iflr->dstaddr)->sa_len);
			if (hostid) {
				ifra.ifra_dstaddr.sin6_addr.s6_addr32[2] =
					hostid->s6_addr32[2];
				ifra.ifra_dstaddr.sin6_addr.s6_addr32[3] =
					hostid->s6_addr32[3];
			}
		}

		ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
		in6_prefixlen2mask(&ifra.ifra_prefixmask.sin6_addr, prefixlen);

		ifra.ifra_flags = iflr->flags & ~IFLR_PREFIX;
#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3)
		return in6_control(so, SIOCAIFADDR_IN6, (caddr_t)&ifra, ifp, p);
#else
		return in6_control(so, SIOCAIFADDR_IN6, (caddr_t)&ifra, ifp);
#endif
	    }
	case SIOCGLIFADDR:
	case SIOCDLIFADDR:
	    {
		struct in6_ifaddr *ia;
		struct in6_addr mask, candidate, match;
		struct sockaddr_in6 *sin6;
		int cmp;

		bzero(&mask, sizeof(mask));
		if (iflr->flags & IFLR_PREFIX) {
			/* lookup a prefix rather than address. */
			in6_prefixlen2mask(&mask, iflr->prefixlen);

			sin6 = (struct sockaddr_in6 *)&iflr->addr;
			bcopy(&sin6->sin6_addr, &match, sizeof(match));
			match.s6_addr32[0] &= mask.s6_addr32[0];
			match.s6_addr32[1] &= mask.s6_addr32[1];
			match.s6_addr32[2] &= mask.s6_addr32[2];
			match.s6_addr32[3] &= mask.s6_addr32[3];

			/* if you set extra bits, that's wrong */
			if (bcmp(&match, &sin6->sin6_addr, sizeof(match)))
				return EINVAL;

			cmp = 1;
		} else {
			if (cmd == SIOCGLIFADDR) {
				/* on getting an address, take the 1st match */
				cmp = 0;	/* XXX */
			} else {
				/* on deleting an address, do exact match */
				in6_prefixlen2mask(&mask, 128);
				sin6 = (struct sockaddr_in6 *)&iflr->addr;
				bcopy(&sin6->sin6_addr, &match, sizeof(match));

				cmp = 1;
			}
		}

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
		for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#elif defined(__FreeBSD__) && __FreeBSD__ >= 4
		TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
#else
		for (ifa = ifp->if_addrlist.tqh_first;
		     ifa;
		     ifa = ifa->ifa_list.tqe_next)
#endif
		{
			if (ifa->ifa_addr->sa_family != AF_INET6)
				continue;
			if (!cmp)
				break;

			bcopy(IFA_IN6(ifa), &candidate, sizeof(candidate));
#ifndef SCOPEDROUTING
			/*
			 * XXX: this is adhoc, but is necessary to allow
			 * a user to specify fe80::/64 (not /10) for a
			 * link-local address.
			 */
			if (IN6_IS_ADDR_LINKLOCAL(&candidate))
				candidate.s6_addr16[1] = 0;
#endif
			candidate.s6_addr32[0] &= mask.s6_addr32[0];
			candidate.s6_addr32[1] &= mask.s6_addr32[1];
			candidate.s6_addr32[2] &= mask.s6_addr32[2];
			candidate.s6_addr32[3] &= mask.s6_addr32[3];
			if (IN6_ARE_ADDR_EQUAL(&candidate, &match))
				break;
		}
		if (!ifa)
			return EADDRNOTAVAIL;
		ia = ifa2ia6(ifa);

		if (cmd == SIOCGLIFADDR) {
#ifndef SCOPEDROUTING
			struct sockaddr_in6 *s6;
#endif

			/* fill in the if_laddrreq structure */
			bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin6_len);
#ifndef SCOPEDROUTING		/* XXX see above */
			s6 = (struct sockaddr_in6 *)&iflr->addr;
			if (IN6_IS_ADDR_LINKLOCAL(&s6->sin6_addr)) {
				s6->sin6_addr.s6_addr16[1] = 0;
				zoneid = in6_addr2zoneid(ifp, &s6->sin6_addr);
				if (zoneid < 0) /* XXX: should not happen */
					return(EINVAL);
				s6->sin6_scope_id = zoneid;
			}
#endif
			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
				bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
					ia->ia_dstaddr.sin6_len);
#ifndef SCOPEDROUTING		/* XXX see above */
				s6 = (struct sockaddr_in6 *)&iflr->dstaddr;
				if (IN6_IS_ADDR_LINKLOCAL(&s6->sin6_addr)) {
					s6->sin6_addr.s6_addr16[1] = 0;
					zoneid = in6_addr2zoneid(ifp,
								 &s6->sin6_addr);
					if (zoneid < 0) /* XXX */
						return(EINVAL);
					s6->sin6_scope_id = zoneid;
				}
#endif
			} else
				bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));

			iflr->prefixlen =
				in6_mask2len(&ia->ia_prefixmask.sin6_addr,
					     NULL);

			iflr->flags = ia->ia6_flags;	/* XXX */

			return 0;
		} else {
			struct in6_aliasreq ifra;

			/* fill in6_aliasreq and do ioctl(SIOCDIFADDR_IN6) */
			bzero(&ifra, sizeof(ifra));
			bcopy(iflr->iflr_name, ifra.ifra_name,
				sizeof(ifra.ifra_name));

			bcopy(&ia->ia_addr, &ifra.ifra_addr,
				ia->ia_addr.sin6_len);
			if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
				bcopy(&ia->ia_dstaddr, &ifra.ifra_dstaddr,
					ia->ia_dstaddr.sin6_len);
			} else {
				bzero(&ifra.ifra_dstaddr,
				    sizeof(ifra.ifra_dstaddr));
			}
			bcopy(&ia->ia_prefixmask, &ifra.ifra_dstaddr,
				ia->ia_prefixmask.sin6_len);

			ifra.ifra_flags = ia->ia6_flags;
#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3)
			return in6_control(so, SIOCDIFADDR_IN6, (caddr_t)&ifra,
				ifp, p);
#else
			return in6_control(so, SIOCDIFADDR_IN6, (caddr_t)&ifra,
				ifp);
#endif
		}
	    }
	}

	return EOPNOTSUPP;	/* just for safety */
}

/*
 * Initialize an interface's intetnet6 address
 * and routing table entry.
 */
static int
in6_ifinit(ifp, ia, sin6, newhost)
	struct ifnet *ifp;
	struct in6_ifaddr *ia;
	struct sockaddr_in6 *sin6;
	int newhost;
{
	int	error = 0, plen, ifacount = 0;
	int	s = splimp();
	struct ifaddr *ifa;

	/*
	 * Give the interface a chance to initialize
	 * if this is its first address,
	 * and to validate the address if necessary.
	 */
#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#elif defined(__FreeBSD__) && __FreeBSD__ >= 4
	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
#else
	for (ifa = ifp->if_addrlist.tqh_first; ifa;
	     ifa = ifa->ifa_list.tqe_next)
#endif
	{
		if (ifa->ifa_addr == NULL)
			continue;	/* just for safety */
		if (ifa->ifa_addr->sa_family != AF_INET6)
			continue;
		ifacount++;
	}

	ia->ia_addr = *sin6;

	if (ifacount <= 1 && ifp->if_ioctl &&
	    (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia))) {
		splx(s);
		return(error);
	}
	splx(s);

	ia->ia_ifa.ifa_metric = ifp->if_metric;

	/* we could do in(6)_socktrim here, but just omit it at this moment. */

	/*
	 * Special case:
	 * If the destination address is specified for a point-to-point
	 * interface, install a route to the destination as an interface
	 * direct route.
	 */
	plen = in6_mask2len(&ia->ia_prefixmask.sin6_addr, NULL); /* XXX */
	if (plen == 128 && ia->ia_dstaddr.sin6_family == AF_INET6) {
		if ((error = rtinit(&(ia->ia_ifa), (int)RTM_ADD,
				    RTF_UP | RTF_HOST)) != 0)
			return(error);
		ia->ia_flags |= IFA_ROUTE;
	}
	if (plen < 128) {
		/*
		 * The RTF_CLONING flag is necessary for in6_is_ifloop_auto().
		 */
		ia->ia_ifa.ifa_flags |= RTF_CLONING;
	}

	/* Add ownaddr as loopback rtentry, if necessary (ex. on p2p link). */
	if (newhost) {
		/* set the rtrequest function to create llinfo */
		ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
		in6_ifaddloop(&(ia->ia_ifa));
	}

#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
	if (ifp->if_flags & IFF_MULTICAST)
		in6_restoremkludge(ia, ifp);
#endif

	return(error);
}

#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
/*
 * Multicast address kludge:
 * If there were any multicast addresses attached to this interface address,
 * either move them to another address on this interface, or save them until
 * such time as this interface is reconfigured for IPv6.
 */
void
in6_savemkludge(oia)
	struct in6_ifaddr *oia;
{
	struct in6_ifaddr *ia;
	struct in6_multi *in6m, *next;

	IFP_TO_IA6(oia->ia_ifp, ia);
	if (ia) {	/* there is another address */
		for (in6m = oia->ia6_multiaddrs.lh_first; in6m; in6m = next){
			next = in6m->in6m_entry.le_next;
			IFAFREE(&in6m->in6m_ia->ia_ifa);
			IFAREF(&ia->ia_ifa);
			in6m->in6m_ia = ia;
			LIST_INSERT_HEAD(&ia->ia6_multiaddrs, in6m, in6m_entry);
		}
	} else {	/* last address on this if deleted, save */
		struct multi6_kludge *mk;

		for (mk = in6_mk.lh_first; mk; mk = mk->mk_entry.le_next) {
			if (mk->mk_ifp == oia->ia_ifp)
				break;
		}
		if (mk == NULL) /* this should not happen! */
			panic("in6_savemkludge: no kludge space");

		for (in6m = oia->ia6_multiaddrs.lh_first; in6m; in6m = next){
			next = in6m->in6m_entry.le_next;
			IFAFREE(&in6m->in6m_ia->ia_ifa); /* release reference */
			in6m->in6m_ia = NULL;
			LIST_INSERT_HEAD(&mk->mk_head, in6m, in6m_entry);
		}
	}
}

/*
 * Continuation of multicast address hack:
 * If there was a multicast group list previously saved for this interface,
 * then we re-attach it to the first address configured on the i/f.
 */
void
in6_restoremkludge(ia, ifp)
	struct in6_ifaddr *ia;
	struct ifnet *ifp;
{
	struct multi6_kludge *mk;

	for (mk = in6_mk.lh_first; mk; mk = mk->mk_entry.le_next) {
		if (mk->mk_ifp == ifp) {
			struct in6_multi *in6m, *next;

			for (in6m = mk->mk_head.lh_first; in6m; in6m = next) {
				next = in6m->in6m_entry.le_next;
				in6m->in6m_ia = ia;
				IFAREF(&ia->ia_ifa);
				LIST_INSERT_HEAD(&ia->ia6_multiaddrs,
						 in6m, in6m_entry);
			}
			LIST_INIT(&mk->mk_head);
			break;
		}
	}
}

/*
 * Allocate space for the kludge at interface initialization time.
 * Formerly, we dynamically allocated the space in in6_savemkludge() with
 * malloc(M_WAITOK).  However, it was wrong since the function could be called
 * under an interrupt context (software timer on address lifetime expiration).
 * Also, we cannot just give up allocating the strucutre, since the group
 * membership structure is very complex and we need to keep it anyway.
 * Of course, this function MUST NOT be called under an interrupt context.
 * Specifically, it is expected to be called only from in6_ifattach(), though
 * it is a global function.
 */
void
in6_createmkludge(ifp)
	struct ifnet *ifp;
{
	struct multi6_kludge *mk;

	for (mk = in6_mk.lh_first; mk; mk = mk->mk_entry.le_next) {
		/* If we've already had one, do not allocate. */
		if (mk->mk_ifp == ifp)
			return;
	}

	mk = malloc(sizeof(*mk), M_IPMADDR, M_WAITOK);

	bzero(mk, sizeof(*mk));
	LIST_INIT(&mk->mk_head);
	mk->mk_ifp = ifp;
	LIST_INSERT_HEAD(&in6_mk, mk, mk_entry);
}

void
in6_purgemkludge(ifp)
	struct ifnet *ifp;
{
	struct multi6_kludge *mk;
	struct in6_multi *in6m;

	for (mk = in6_mk.lh_first; mk; mk = mk->mk_entry.le_next) {
		if (mk->mk_ifp != ifp)
			continue;

		/* leave from all multicast groups joined */
		while ((in6m = LIST_FIRST(&mk->mk_head)) != NULL)
			in6_delmulti(in6m);
		LIST_REMOVE(mk, mk_entry);
		free(mk, M_IPMADDR);
		break;
	}
}

/*
 * Add an address to the list of IP6 multicast addresses for a
 * given interface.
 */
struct	in6_multi *
in6_addmulti(maddr6, ifp, errorp)
	struct in6_addr *maddr6;
	struct ifnet *ifp;
	int *errorp;
{
	struct	in6_ifaddr *ia;
	struct	in6_ifreq ifr;
	struct	in6_multi *in6m;
#ifdef __NetBSD__
	int	s = splsoftnet();
#else
	int	s = splnet();
#endif

	*errorp = 0;
	/*
	 * See if address already in list.
	 */
	IN6_LOOKUP_MULTI(*maddr6, ifp, in6m);
	if (in6m != NULL) {
		/*
		 * Found it; just increment the refrence count.
		 */
		in6m->in6m_refcount++;
	} else {
		/*
		 * New address; allocate a new multicast record
		 * and link it into the interface's multicast list.
		 */
		in6m = (struct in6_multi *)
			malloc(sizeof(*in6m), M_IPMADDR, M_NOWAIT);
		if (in6m == NULL) {
			splx(s);
			*errorp = ENOBUFS;
			return(NULL);
		}
		in6m->in6m_addr = *maddr6;
		in6m->in6m_ifp = ifp;
		in6m->in6m_refcount = 1;
		IFP_TO_IA6(ifp, ia);
		if (ia == NULL) {
			free(in6m, M_IPMADDR);
			splx(s);
			*errorp = EADDRNOTAVAIL; /* appropriate? */
			return(NULL);
		}
		in6m->in6m_ia = ia;
		IFAREF(&ia->ia_ifa); /* gain a reference */
		LIST_INSERT_HEAD(&ia->ia6_multiaddrs, in6m, in6m_entry);

		/*
		 * Ask the network driver to update its multicast reception
		 * filter appropriately for the new address.
		 */
		bzero(&ifr.ifr_addr, sizeof(struct sockaddr_in6));
		ifr.ifr_addr.sin6_len = sizeof(struct sockaddr_in6);
		ifr.ifr_addr.sin6_family = AF_INET6;
		ifr.ifr_addr.sin6_addr = *maddr6;
		if (ifp->if_ioctl == NULL)
			*errorp = ENXIO; /* XXX: appropriate? */
		else
			*errorp = (*ifp->if_ioctl)(ifp, SIOCADDMULTI,
						    (caddr_t)&ifr);
		if (*errorp) {
			LIST_REMOVE(in6m, in6m_entry);
			free(in6m, M_IPMADDR);
			IFAFREE(&ia->ia_ifa);
			splx(s);
			return(NULL);
		}
		/*
		 * Let MLD6 know that we have joined a new IP6 multicast
		 * group.
		 */
		mld6_start_listening(in6m);
	}
	splx(s);
	return(in6m);
}

/*
 * Delete a multicast address record.
 */
void
in6_delmulti(in6m)
	struct in6_multi *in6m;
{
	struct	in6_ifreq ifr;
#ifdef __NetBSD__
	int	s = splsoftnet();
#else
	int	s = splnet();
#endif

	if (--in6m->in6m_refcount == 0) {
		/*
		 * No remaining claims to this record; let MLD6 know
		 * that we are leaving the multicast group.
		 */
		mld6_stop_listening(in6m);

		/*
		 * Unlink from list.
		 */
		LIST_REMOVE(in6m, in6m_entry);
		if (in6m->in6m_ia) {
			IFAFREE(&in6m->in6m_ia->ia_ifa); /* release reference */
		}

		/*
		 * Notify the network driver to update its multicast
		 * reception filter.
		 */
		bzero(&ifr.ifr_addr, sizeof(struct sockaddr_in6));
		ifr.ifr_addr.sin6_len = sizeof(struct sockaddr_in6);
		ifr.ifr_addr.sin6_family = AF_INET6;
		ifr.ifr_addr.sin6_addr = in6m->in6m_addr;
		(*in6m->in6m_ifp->if_ioctl)(in6m->in6m_ifp,
					    SIOCDELMULTI, (caddr_t)&ifr);
		free(in6m, M_IPMADDR);
	}
	splx(s);
}
#else /* not FreeBSD3 */
/*
 * Add an address to the list of IP6 multicast addresses for a
 * given interface.
 */
struct	in6_multi *
in6_addmulti(maddr6, ifp, errorp)
	struct in6_addr *maddr6;
	struct ifnet *ifp;
	int *errorp;
{
	struct	in6_multi *in6m;
	struct sockaddr_in6 sin6;
	struct ifmultiaddr *ifma;
	int	s = splnet();

	*errorp = 0;

	/*
	 * Call generic routine to add membership or increment
	 * refcount.  It wants addresses in the form of a sockaddr,
	 * so we build one here (being careful to zero the unused bytes).
	 */
	bzero(&sin6, sizeof sin6);
	sin6.sin6_family = AF_INET6;
	sin6.sin6_len = sizeof sin6;
	sin6.sin6_addr = *maddr6;
	*errorp = if_addmulti(ifp, (struct sockaddr *)&sin6, &ifma);
	if (*errorp) {
		splx(s);
		return 0;
	}

	/*
	 * If ifma->ifma_protospec is null, then if_addmulti() created
	 * a new record.  Otherwise, we are done.
	 */
	if (ifma->ifma_protospec != 0)
		return ifma->ifma_protospec;

	/* XXX - if_addmulti uses M_WAITOK.  Can this really be called
	   at interrupt time?  If so, need to fix if_addmulti. XXX */
	in6m = (struct in6_multi *)malloc(sizeof(*in6m), M_IPMADDR, M_NOWAIT);
	if (in6m == NULL) {
		splx(s);
		return (NULL);
	}

	bzero(in6m, sizeof *in6m);
	in6m->in6m_addr = *maddr6;
	in6m->in6m_ifp = ifp;
	in6m->in6m_ifma = ifma;
	ifma->ifma_protospec = in6m;
	LIST_INSERT_HEAD(&in6_multihead, in6m, in6m_entry);

	/*
	 * Let MLD6 know that we have joined a new IP6 multicast
	 * group.
	 */
	mld6_start_listening(in6m);
	splx(s);
	return(in6m);
}

/*
 * Delete a multicast address record.
 */
void
in6_delmulti(in6m)
	struct in6_multi *in6m;
{
	struct ifmultiaddr *ifma = in6m->in6m_ifma;
	int	s = splnet();

	if (ifma->ifma_refcount == 1) {
		/*
		 * No remaining claims to this record; let MLD6 know
		 * that we are leaving the multicast group.
		 */
		mld6_stop_listening(in6m);
		ifma->ifma_protospec = 0;
		LIST_REMOVE(in6m, in6m_entry);
		free(in6m, M_IPMADDR);
	}
	/* XXX - should be separate API for when we have an ifma? */
	if_delmulti(ifma->ifma_ifp, ifma->ifma_addr);
	splx(s);
}
#endif /* not FreeBSD3 */

struct in6_multi_mship *
in6_joingroup(ifp, addr, errorp)
	struct ifnet *ifp;
	struct in6_addr *addr;
	int *errorp;
{
	struct in6_multi_mship *imm;

	imm = malloc(sizeof(*imm), M_IPMADDR, M_NOWAIT);
	if (!imm) {
		*errorp = ENOBUFS;
		return NULL;
	}
	imm->i6mm_maddr = in6_addmulti(addr, ifp, errorp);
	if (!imm->i6mm_maddr) {
		/* *errorp is alrady set */
		free(imm, M_IPMADDR);
		return NULL;
	}
	return imm;
}

int
in6_leavegroup(imm)
	struct in6_multi_mship *imm;
{

	if (imm->i6mm_maddr)
		in6_delmulti(imm->i6mm_maddr);
	free(imm,  M_IPMADDR);
	return 0;
}

/*
 * Find an IPv6 interface link-local address specific to an interface.
 */
struct in6_ifaddr *
in6ifa_ifpforlinklocal(ifp, ignoreflags)
	struct ifnet *ifp;
	int ignoreflags;
{
	struct ifaddr *ifa;

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#elif defined(__FreeBSD__) && __FreeBSD__ >= 4
	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
#else
	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
#endif
	{
		if (ifa->ifa_addr == NULL)
			continue;	/* just for safety */
		if (ifa->ifa_addr->sa_family != AF_INET6)
			continue;
		if (IN6_IS_ADDR_LINKLOCAL(IFA_IN6(ifa))) {
			if ((((struct in6_ifaddr *)ifa)->ia6_flags &
			     ignoreflags) != 0)
				continue;
			break;
		}
	}

	return((struct in6_ifaddr *)ifa);
}


/*
 * find the internet address corresponding to a given interface and address.
 */
static struct in6_ifaddr *
_in6ifa_ifpwithaddr(struct ifnet *ifp, struct in6_addr *addr)
{
	struct ifaddr *ifa;

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#elif defined(__FreeBSD__) && __FreeBSD__ >= 4
	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
#else
	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
#endif
	{
		if (ifa->ifa_addr == NULL)
			continue;	/* just for safety */
		if (ifa->ifa_addr->sa_family != AF_INET6)
			continue;
		if (IN6_ARE_ADDR_EQUAL(addr, IFA_IN6(ifa)))
			break;
	}

	return((struct in6_ifaddr *)ifa);
}

struct in6_ifaddr *
in6ifa_ifpwithaddr(ifp, addr)
	struct ifnet *ifp;
	struct in6_addr *addr;
{
    struct in6_ifaddr *_ifa = _in6ifa_ifpwithaddr(ifp, addr);
#if 0
    if (!_ifa) {
        struct ifaddr *ifa;

        diag_printf("%s\n", __FUNCTION__);
        diag_dump_buf(addr, 16);
        diag_printf("==============================================================\n");
	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
	{
		if (ifa->ifa_addr == NULL)
			continue;	/* just for safety */
		if (ifa->ifa_addr->sa_family != AF_INET6)
			continue;
                diag_dump_buf(IFA_IN6(ifa), 16);
                diag_printf("--------------------------------------------------------------\n");
	}
    }
#endif
    return(_ifa);
}

/*
 * Convert IP6 address to printable (loggable) representation.
 */
static char digits[] = "0123456789abcdef";
static int ip6round = 0;
char *
ip6_sprintf(addr)
	const struct in6_addr *addr;
{
	static char ip6buf[8][48];
	int i;
	char *cp;
	const u_short *a = (const u_short *)addr;
	const u_char *d;
	int dcolon = 0;

	ip6round = (ip6round + 1) & 7;
	cp = ip6buf[ip6round];

	for (i = 0; i < 8; i++) {
		if (dcolon == 1) {
			if (*a == 0) {
				if (i == 7)
					*cp++ = ':';
				a++;
				continue;
			} else
				dcolon = 2;
		}
		if (*a == 0) {
			if (dcolon == 0 && *(a + 1) == 0) {
				if (i == 0)
					*cp++ = ':';
				*cp++ = ':';
				dcolon = 1;
			} else {
				*cp++ = '0';
				*cp++ = ':';
			}
			a++;
			continue;
		}
		d = (const u_char *)a;
		*cp++ = digits[*d >> 4];
		*cp++ = digits[*d++ & 0xf];
		*cp++ = digits[*d >> 4];
		*cp++ = digits[*d & 0xf];
		*cp++ = ':';
		a++;
	}
	*--cp = 0;
	return(ip6buf[ip6round]);
}

int
in6_localaddr(in6)
	struct in6_addr *in6;
{
	struct in6_ifaddr *ia;

	if (IN6_IS_ADDR_LOOPBACK(in6) || IN6_IS_ADDR_LINKLOCAL(in6))
		return 1;

	for (ia = in6_ifaddr; ia; ia = ia->ia_next)
		if (IN6_ARE_MASKED_ADDR_EQUAL(in6, &ia->ia_addr.sin6_addr,
					      &ia->ia_prefixmask.sin6_addr))
			return 1;

	return (0);
}

int
in6_is_addr_deprecated(sa6)
	struct sockaddr_in6 *sa6;
{
	struct in6_ifaddr *ia;

	for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
		if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
				       &sa6->sin6_addr) &&
#ifdef SCOPEDROUTING
		    ia->ia_addr.sin6_scope_id == sa6->sin6_scope_id &&
#endif
		    (ia->ia6_flags & IN6_IFF_DEPRECATED) != 0)
			return(1); /* true */

		/* XXX: do we still have to go thru the rest of the list? */
	}

	return(0);		/* false */
}

/*
 * return length of part which dst and src are equal
 * hard coding...
 */
int
in6_matchlen(src, dst)
struct in6_addr *src, *dst;
{
	int match = 0;
	u_char *s = (u_char *)src, *d = (u_char *)dst;
	u_char *lim = s + 16, r;

	while (s < lim)
		if ((r = (*d++ ^ *s++)) != 0) {
			while (r < 128) {
				match++;
				r <<= 1;
			}
			break;
		} else
			match += 8;
	return match;
}

/* XXX: to be scope conscious */
int
in6_are_prefix_equal(p1, p2, len)
	struct in6_addr *p1, *p2;
	int len;
{
	int bytelen, bitlen;

	/* sanity check */
	if (0 > len || len > 128) {
		log(LOG_ERR, "in6_are_prefix_equal: invalid prefix length(%d)\n",
		    len);
		return(0);
	}

	bytelen = len / 8;
	bitlen = len % 8;

	if (bcmp(&p1->s6_addr, &p2->s6_addr, bytelen))
		return(0);
	if (p1->s6_addr[bytelen] >> (8 - bitlen) !=
	    p2->s6_addr[bytelen] >> (8 - bitlen))
		return(0);

	return(1);
}

void
in6_prefixlen2mask(maskp, len)
	struct in6_addr *maskp;
	int len;
{
	u_char maskarray[8] = {0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff};
	int bytelen, bitlen, i;

	/* sanity check */
	if (0 > len || len > 128) {
		log(LOG_ERR, "in6_prefixlen2mask: invalid prefix length(%d)\n",
		    len);
		return;
	}

	bzero(maskp, sizeof(*maskp));
	bytelen = len / 8;
	bitlen = len % 8;
	for (i = 0; i < bytelen; i++)
		maskp->s6_addr[i] = 0xff;
	if (bitlen)
		maskp->s6_addr[bytelen] = maskarray[bitlen - 1];
}

/*
 * return the best address out of the same scope. if no address was
 * found, return the first valid address from designated IF.
 */
struct in6_ifaddr *
in6_ifawithifp(ifp, dst)
	struct ifnet *ifp;
	struct in6_addr *dst;
{
	int dst_scope =	in6_addrscope(dst), blen = -1, tlen;
	struct ifaddr *ifa;
	struct in6_ifaddr *besta = 0;
	struct in6_ifaddr *dep[2];	/* last-resort: deprecated */

	dep[0] = dep[1] = NULL;

	/*
	 * We first look for addresses in the same scope.
	 * If there is one, return it.
	 * If two or more, return one which matches the dst longest.
	 * If none, return one of global addresses assigned other ifs.
	 */
#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#elif defined(__FreeBSD__) && __FreeBSD__ >= 4
	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
#else
	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
#endif
	{
		if (ifa->ifa_addr->sa_family != AF_INET6)
			continue;
		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)
			continue; /* XXX: is there any case to allow anycast? */
		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_NOTREADY)
			continue; /* don't use this interface */
		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DETACHED)
			continue;
		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DEPRECATED) {
			if (ip6_use_deprecated)
				dep[0] = (struct in6_ifaddr *)ifa;
			continue;
		}

		if (dst_scope == in6_addrscope(IFA_IN6(ifa))) {
			/*
			 * call in6_matchlen() as few as possible
			 */
			if (besta) {
				if (blen == -1)
					blen = in6_matchlen(&besta->ia_addr.sin6_addr, dst);
				tlen = in6_matchlen(IFA_IN6(ifa), dst);
				if (tlen > blen) {
					blen = tlen;
					besta = (struct in6_ifaddr *)ifa;
				}
			} else
				besta = (struct in6_ifaddr *)ifa;
		}
	}
	if (besta)
		return(besta);

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#elif defined(__FreeBSD__) && __FreeBSD__ >= 4
	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
#else
	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
#endif
	{
		if (ifa->ifa_addr->sa_family != AF_INET6)
			continue;
		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_ANYCAST)
			continue; /* XXX: is there any case to allow anycast? */
		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_NOTREADY)
			continue; /* don't use this interface */
		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DETACHED)
			continue;
		if (((struct in6_ifaddr *)ifa)->ia6_flags & IN6_IFF_DEPRECATED) {
			if (ip6_use_deprecated)
				dep[1] = (struct in6_ifaddr *)ifa;
			continue;
		}

		return (struct in6_ifaddr *)ifa;
	}

	/* use the last-resort values, that are, deprecated addresses */
	if (dep[0])
		return dep[0];
	if (dep[1])
		return dep[1];

	return NULL;
}

/*
 * perform DAD when interface becomes IFF_UP.
 */
void
in6_if_up(ifp)
	struct ifnet *ifp;
{
	struct ifaddr *ifa;
	struct in6_ifaddr *ia;
	int dad_delay;		/* delay ticks before DAD output */

	/*
	 * special cases, like 6to4, are handled in in6_ifattach
	 */
	in6_ifattach(ifp, NULL);

	dad_delay = 0;
#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#elif defined(__FreeBSD__) && __FreeBSD__ >= 4
	TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list)
#else
	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
#endif
	{
		if (ifa->ifa_addr->sa_family != AF_INET6)
			continue;
		ia = (struct in6_ifaddr *)ifa;
		if (ia->ia6_flags & IN6_IFF_TENTATIVE)
			nd6_dad_start(ifa, &dad_delay);
	}
}

int
in6if_do_dad(ifp)
	struct ifnet *ifp;
{
	if ((ifp->if_flags & IFF_LOOPBACK) != 0)
		return(0);

	switch (ifp->if_type) {
#ifdef IFT_DUMMY
	case IFT_DUMMY:
#endif
	case IFT_FAITH:
		/*
		 * These interfaces do not have the IFF_LOOPBACK flag,
		 * but loop packets back.  We do not have to do DAD on such
		 * interfaces.  We should even omit it, because loop-backed
		 * NS would confuse the DAD procedure.
		 */
		return(0);
	default:
		/*
		 * Our DAD routine requires the interface up and running.
		 * However, some interfaces can be up before the RUNNING
		 * status.  Additionaly, users may try to assign addresses
		 * before the interface becomes up (or running).
		 * We simply skip DAD in such a case as a work around.
		 * XXX: we should rather mark "tentative" on such addresses,
		 * and do DAD after the interface becomes ready.
		 */
		if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) !=
		    (IFF_UP|IFF_RUNNING))
			return(0);

		return(1);
	}
}

/*
 * Calculate max IPv6 MTU through all the interfaces and store it
 * to in6_maxmtu.
 */
void
in6_setmaxmtu()
{
	unsigned long maxmtu = 0;
	struct ifnet *ifp;

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
	for (ifp = ifnet; ifp; ifp = ifp->if_next)
#else
	for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list))
#endif
	{
		if ((ifp->if_flags & IFF_LOOPBACK) == 0 &&
		    nd_ifinfo[ifp->if_index].linkmtu > maxmtu)
			maxmtu =  nd_ifinfo[ifp->if_index].linkmtu;
	}
	if (maxmtu)	/* update only when maxmtu is positive */
		in6_maxmtu = maxmtu;
}

#if defined(__FreeBSD__) && __FreeBSD__ >= 3
/*
 * Convert sockaddr_in6 to sockaddr_in.  Original sockaddr_in6 must be
 * v4 mapped addr or v4 compat addr
 */
void
in6_sin6_2_sin(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
{
	bzero(sin, sizeof(*sin));
	sin->sin_len = sizeof(struct sockaddr_in);
	sin->sin_family = AF_INET;
	sin->sin_port = sin6->sin6_port;
	sin->sin_addr.s_addr = sin6->sin6_addr.s6_addr32[3];	
}

/* Convert sockaddr_in to sockaddr_in6 in v4 mapped addr format. */
void
in6_sin_2_v4mapsin6(struct sockaddr_in *sin, struct sockaddr_in6 *sin6)
{
	bzero(sin6, sizeof(*sin6));
	sin6->sin6_len = sizeof(struct sockaddr_in6);
	sin6->sin6_family = AF_INET6;
	sin6->sin6_port = sin->sin_port;
	sin6->sin6_addr.s6_addr32[0] = 0;
	sin6->sin6_addr.s6_addr32[1] = 0;
	sin6->sin6_addr.s6_addr32[2] = IPV6_ADDR_INT32_SMP;
	sin6->sin6_addr.s6_addr32[3] = sin->sin_addr.s_addr;
}

/* Convert sockaddr_in6 into sockaddr_in. */
void
in6_sin6_2_sin_in_sock(struct sockaddr *nam)
{
	struct sockaddr_in *sin_p;
	struct sockaddr_in6 sin6;

	/*
	 * Save original sockaddr_in6 addr and convert it
	 * to sockaddr_in.
	 */
	sin6 = *(struct sockaddr_in6 *)nam;
	sin_p = (struct sockaddr_in *)nam;
	in6_sin6_2_sin(sin_p, &sin6);
}

/* Convert sockaddr_in into sockaddr_in6 in v4 mapped addr format. */
void
in6_sin_2_v4mapsin6_in_sock(struct sockaddr **nam)
{
	struct sockaddr_in *sin_p;
	struct sockaddr_in6 *sin6_p;

	MALLOC(sin6_p, struct sockaddr_in6 *, sizeof *sin6_p, M_SONAME,
	       M_WAITOK);
	sin_p = (struct sockaddr_in *)*nam;
	in6_sin_2_v4mapsin6(sin_p, sin6_p);
	FREE(*nam, M_SONAME);
	*nam = (struct sockaddr *)sin6_p;
}
#endif /* freebsd3 */

#ifdef MEASURE_PERFORMANCE
#define IN6_MAXADDRHASH 1000
#ifndef	IN6_ADDRHASH
#ifndef INET6_SERVER
#define	IN6_ADDRHASH	23
#else
#define	IN6_ADDRHASH	997
#endif
#endif

static struct in6hash in6h_hash_any = { NULL, IN6ADDR_ANY_INIT, NULL, 0 };
struct in6hash *in6hash[IN6_MAXADDRHASH];/* hash buckets for local IPv6 addrs */
int in6_nhash = IN6_ADDRHASH;		/* number of hash buckets for addrs */
int in6_hash_nullhit;

#define HASH6(in6) ((in6)->s6_addr32[0]^(in6)->s6_addr32[1]^\
	(in6)->s6_addr32[2]^(in6)->s6_addr32[3])

/*
 * Initialize the hash by adding entries for IN6ADDR_ANY
 */
struct in6hash *ih_cache = NULL;

void
in6h_hashinit()
{
	in6h_addhash(&in6h_hash_any);
}

void
in6h_addifa(ia)
	struct in6_ifaddr *ia;
{
	if (ia->ia6_hash.in6h_ifa == NULL)
		ia->ia6_hash.in6h_ifa = ia;

	ia->ia6_hash.in6h_addr = IA6_SIN6(ia)->sin6_addr; /* scope? */
	if (IN6_IS_ADDR_UNSPECIFIED(&ia->ia6_hash.in6h_addr))
		return;
	in6h_addhash(&ia->ia6_hash);
}

/*
 * Rebuild the hash when any interface addresses have been changed.
 * Since this should happen infrequently we remove all the interfaces
 * from the hash and add them all back.  This insures that the order
 * of addresses in the hash is consistent.
 */
void
in6h_rebuild(newhashsiz)
	int newhashsiz;		/* can be 0, meaning unchange the size */
{
	struct in6_ifaddr *ia;

	if (newhashsiz > IN6_MAXADDRHASH)
		return;		/* XXX invalid */

	for (ia = in6_ifaddr; ia != NULL; ia = ia->ia_next)
		in6h_delifa(ia);

	if (newhashsiz)
		in6_nhash = newhashsiz;

	for (ia = in6_ifaddr; ia != NULL; ia = ia->ia_next)
		in6h_addifa(ia);
}

/* Remove hash entries for local address on an in6_ifaddr. */
void
in6h_delifa(ia)
	struct in6_ifaddr *ia;
{
	if (IN6_IS_ADDR_UNSPECIFIED(&ia->ia6_hash.in6h_addr))
		return;
	in6h_delhash(&ia->ia6_hash);
	ia->ia6_hash.in6h_addr = in6addr_any;
}

static void
in6h_addhash(ih)
	struct in6hash *ih;
{
	struct in6hash **prev;

	/* Add to tail of hash list, as address is at end of address list */
	for (prev = &in6hash[HASH6(&ih->in6h_addr) % in6_nhash]; *prev;
	     prev = &((*prev)->in6h_next)) {
		/* however, we always prefer non-global addresses */
		if (IN6_IS_ADDR_LINKLOCAL(&(*prev)->in6h_addr))
			break;
	}
	ih->in6h_next = *prev;
	*prev = ih;
}

static void
in6h_delhash(ih)
	struct in6hash *ih;
{
	struct in6hash **prev;

	ih_cache = NULL;

	for (prev = &in6hash[HASH6(&ih->in6h_addr) % in6_nhash];
	     *prev != ih; prev = &((*prev)->in6h_next)) {
#ifdef DEBUG
		if (*prev == NULL)
			panic("in6h_delhash: lost entry");
#endif
	}
	*prev = (*prev)->in6h_next;
}

/*
 * Look up hash structure for specified IP address
 * and (optional) interface; matches any interface
 * if ifp is null, or this address is not associated
 * with the specified interface.
 */
struct in6hash *
in6h_lookup(addr, ifp) 
	const struct in6_addr *addr;
	struct ifnet *ifp;
{
	struct in6hash *ih, *maybe_ih = NULL;

	/* just for measurement */
	if ((ih = in6hash[HASH6(addr) % in6_nhash]) == NULL)
		in6_hash_nullhit++;

	for (; ih; ih = ih->in6h_next) {
		if (IN6_ARE_ADDR_EQUAL(&ih->in6h_addr, addr)) {
			ih->in6h_hit++;

			if (ih->in6h_ifa == NULL ||
			    ih->in6h_ifa->ia_ifp == ifp || ifp == NULL) {
				ih_cache = ih;
				return (ih);
			}
			if (maybe_ih == NULL)
				maybe_ih = ih;
		}
		else
			ih->in6h_miss++;
	}
	if (maybe_ih)
		ih_cache = maybe_ih;
	return (maybe_ih);
}
#endif /* MEASURE_PERFORMANCE */
