xnu-201.tar.gz

[apple/xnu.git] / bsd / netinet6 / in6.c

/*      $KAME: in6.c,v 1.72 2000/03/30 03:45:26 itojun 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
 */

#if (defined(__FreeBSD__) && __FreeBSD__ >= 3) || defined(__NetBSD__)
#include "opt_inet.h"
#endif

#include <sys/param.h>
#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)
#include <sys/ioctl.h>
#endif
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sockio.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>

#include <net/if.h>
#include <net/if_types.h>
#include <net/route.h>
#include "gif.h"
#if NGIF > 0
#include <net/if_gif.h>
#endif
#include <net/if_dl.h>

#include <netinet/in.h>
#include <netinet/in_var.h>
#if __NetBSD__
#include <net/if_ether.h>
#else
#include <netinet/if_ether.h>
#endif

#include <netinet6/nd6.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/mld6_var.h>
#include <netinet6/ip6_mroute.h>
#include <netinet6/in6_ifattach.h>

#include <net/net_osdep.h>

#if MIP6
#include <netinet6/mip6.h>
#include <netinet6/mip6_common.h>

struct nd_prefix *(*mip6_get_home_prefix_hook) __P((void));
#endif /* MIP6 */

#if defined(__FreeBSD__) && __FreeBSD__ >= 3
MALLOC_DEFINE(M_IPMADDR, "in6_multi", "internet multicast address");
#endif

/*
 * 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;

#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3) && !defined (__APPLE__)
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

#if defined(__FreeBSD__) && __FreeBSD__ >= 3 || defined (__APPLE__)
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

/*
 * Check if the loopback entry will be automatically generated.
 *   if 0 returned, will not be automatically generated.
 *   if 1 returned, will be automatically generated.
 */
static int
in6_is_ifloop_auto(struct ifaddr *ifa)
{
#define SIN6(s) ((struct sockaddr_in6 *)s)
        /*
         * If RTF_CLONING is unset, or (IFF_LOOPBACK | IFF_POINTOPOINT),
         * or netmask is all0 or all1, then cloning will not happen,
         * then we can't rely on its loopback entry generation.
         */
        if ((ifa->ifa_flags & RTF_CLONING) == 0 ||
            (ifa->ifa_ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) ||
            (SIN6(ifa->ifa_netmask)->sin6_len == sizeof(struct sockaddr_in6)
             &&
             IN6_ARE_ADDR_EQUAL(&SIN6(ifa->ifa_netmask)->sin6_addr,
                                &in6mask128)) ||
            ((struct sockaddr_in6 *)ifa->ifa_netmask)->sin6_len == 0)
                return 0;
        else
                return 1;
#undef SIN6
}

/*
 * 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 lo_sa;
        struct sockaddr_in6 all1_sa;
        struct rtentry *nrt = NULL;
        
        bzero(&lo_sa, sizeof(lo_sa));
        bzero(&all1_sa, sizeof(all1_sa));
        lo_sa.sin6_family = AF_INET6;
        lo_sa.sin6_len = sizeof(struct sockaddr_in6);
        all1_sa = lo_sa;
        lo_sa.sin6_addr = in6addr_loopback;
        all1_sa.sin6_addr = in6mask128;
        
        /* So we add or remove static loopback entry, here. */
        rtrequest(cmd, ifa->ifa_addr,
                  (struct sockaddr *)&lo_sa,
                  (struct sockaddr *)&all1_sa,
                  RTF_UP|RTF_HOST, &nrt);

        /*
         * Make sure rt_ifa be equal to IFA, the second argument of the
         * function.
         * We need this because when we refer 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);
                ifa->ifa_refcnt++;
                nrt->rt_ifa = ifa;
                nrt->rt_dlt = ifa->ifa_dlt;
        }
        if (nrt)
                nrt->rt_refcnt--;
}

/*
 * Add ownaddr as loopback rtentry, if necessary(ex. on p2p link).
 * Because, KAME needs loopback rtentry for ownaddr check in
 * ip6_input().
 */
static void
in6_ifaddloop(struct ifaddr *ifa)
{
        if (!in6_is_ifloop_auto(ifa)) {
                struct rtentry *rt;

                /* If there is no loopback entry, allocate one. */
                rt = rtalloc1(ifa->ifa_addr, 0
#if defined(__FreeBSD__) || defined (__APPLE__)
                              , 0
#endif /* __FreeBSD__ */
                              );
                if (rt == 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)
{
        if (!in6_is_ifloop_auto(ifa)) {
                struct in6_ifaddr *ia;
                int ia_count = 0;

                /* If only one ifa for the loopback entry, delete it. */
                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)
                        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;
        ifp = ifindex2ifnet[idx];

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3) 
        for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#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)
        struct in6_addr *mask;
{
        int x, y;

        for (x = 0; x < sizeof(*mask); x++) {
                if (mask->s6_addr8[x] != 0xff)
                        break;
        }
        y = 0;
        if (x < sizeof(*mask)) {
                for (y = 0; y < 8; y++) {
                        if ((mask->s6_addr8[x] & (0x80 >> y)) == 0)
                                break;
                }
        }
        return x * 8 + y;
}

void
in6_len2mask(mask, len)
        struct in6_addr *mask;
        int len;
{
        int i;

        bzero(mask, sizeof(*mask));
        for (i = 0; i < len / 8; i++)
                mask->s6_addr8[i] = 0xff;
        if (len % 8)
                mask->s6_addr8[i] = (0xff00 >> (len % 8)) & 0xff;
}

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

int
#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3) && !defined (__APPLE__)
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;
#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
        struct  ifaddr *ifa;
#endif
        struct  in6_ifaddr *ia = NULL, *oia;
        struct  in6_aliasreq *ifra = (struct in6_aliasreq *)data;
        struct  sockaddr_in6 oldaddr;
#ifdef COMPAT_IN6IFIOCTL
        struct  sockaddr_in6 net;
#endif
        int error = 0, hostIsNew, prefixIsNew;
        int newifaddr;
#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3) && !defined(__APPLE__)
        time_t time_second = (time_t)time.tv_sec;
#endif
        int privileged;
        u_long dl_tag;

        privileged = 0;
#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3) && !defined (__APPLE__)
        if (p && !suser(p->p_ucred, &p->p_acflag))
                privileged++;
#else
        if ((so->so_state & SS_PRIV) != 0)
                privileged++;
#endif

        /*
         * xxx should prevent processes for link-local addresses?
         */
#if NGIF > 0
        if (ifp && ifp->if_type == IFT_GIF) {
                switch (cmd) {
                case SIOCSIFPHYADDR_IN6:
                        if (!privileged)
                                return(EPERM);
                        /*fall through*/
                case SIOCGIFPSRCADDR_IN6:
                case SIOCGIFPDSTADDR_IN6:
                        return gif_ioctl(ifp, cmd, data);
                }
        }
#endif
        switch (cmd) {
        case SIOCGETSGCNT_IN6:
        case SIOCGETMIFCNT_IN6:
                return (mrt6_ioctl(cmd, data));
        }
#if MIP6
        /* These require root privileges */
        switch (cmd) {
        case SIOCSDEBUG_MIP6:
        case SIOCSBCFLUSH_MIP6:
        case SIOCSDEFCONFIG_MIP6:
        case SIOCSBRUPDATE_MIP6:
        case SIOCSENABLEBR_MIP6:
        case SIOCSATTACH_MIP6:
        case SIOCSRELEASE_MIP6:

        case SIOCSHALISTFLUSH_MIP6:
        case SIOCSHAPREF_MIP6:
        case SIOCSFWDSLUNICAST_MIP6:
        case SIOCSFWDSLMULTICAST_MIP6:

        case SIOCSFORADDRFLUSH_MIP6:
        case SIOCSHADDRFLUSH_MIP6:
        case SIOCSBULISTFLUSH_MIP6:
        case SIOCACOADDR_MIP6:
        case SIOCAHOMEADDR_MIP6:
        case SIOCSBULIFETIME_MIP6:
        case SIOCSHRLIFETIME_MIP6:
        case SIOCDCOADDR_MIP6:
        case SIOCSPROMMODE_MIP6:
        case SIOCSBU2CN_MIP6:
        case SIOCSREVTUNNEL_MIP6:
        case SIOCSAUTOCONFIG_MIP6:
        case SIOCSEAGERMD_MIP6:
                if (!privileged)
                        return(EPERM);
                /* Anyone can use these or the user is root */
                /* case SIOCXVERYSAFECOMMAND_MIP6:  */
#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3) && !defined(__APPLE__)
                return mip6_ioctl(so, cmd, data, ifp, p);
#else
                return mip6_ioctl(so, cmd, data, ifp);
#endif
        }
#endif /* MIP6 */

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

        switch (cmd) {
        case SIOCSNDFLUSH_IN6:
        case SIOCSPFXFLUSH_IN6:
        case SIOCSRTRFLUSH_IN6:
        case SIOCSDEFIFACE_IN6:
        case SIOCSIFINFO_FLAGS:
                if (!privileged)
                        return(EPERM);
                /*fall through*/
        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:
                if (!privileged)
                        return(EPERM);
                /*fall through*/
        case SIOCGIFPREFIX_IN6:
                if (ip6_forwarding == 0)
                        return(EPERM);
                return(in6_prefix_ioctl(so, cmd, data, ifp));
        }

        switch (cmd) {
        case SIOCALIFADDR:
        case SIOCDLIFADDR:
                if (!privileged)
                        return(EPERM);
                /*fall through*/
        case SIOCGLIFADDR:
#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3) && !defined (__APPLE__)
                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.
         */
        if (ifra->ifra_addr.sin6_family == AF_INET6) { /* XXX */
                struct sockaddr_in6 *sa6 =
                        (struct sockaddr_in6 *)&ifra->ifra_addr;

                if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) {
                        if (sa6->sin6_addr.s6_addr16[1] == 0) {
                                /* interface 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); /* ifid is contradict */
                        }
                        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, &ifra->ifra_addr.sin6_addr);
        }

        switch (cmd) {

        case SIOCDIFADDR_IN6:
                /*
                 * for IPv4, we look for existing in6_ifaddr here to allow
                 * "ifconfig if0 delete" to remove first IPv4 address on the
                 * interface.  For IPv6, as the spec allow multiple interface
                 * address from the day one, we consider "remove the first one"
                 * semantics to be not preferrable.
                 */
                if (ia == NULL)
                        return(EADDRNOTAVAIL);
                /* FALLTHROUGH */
        case SIOCAIFADDR_IN6:
        case SIOCSIFADDR_IN6:
#if COMPAT_IN6IFIOCTL
        case SIOCSIFDSTADDR_IN6:
        case SIOCSIFNETMASK_IN6:
                /*
                 * Since IPv6 allows a node to assign multiple addresses
                 * on a single interface, SIOCSIFxxx ioctls are not suitable
                 * and should be unused.
                 */
#endif
                if (ifra->ifra_addr.sin6_family != AF_INET6)
                        return(EAFNOSUPPORT);
                if (!privileged)
                        return(EPERM);
                if (ia == NULL) {
                        ia = (struct in6_ifaddr *)
                                _MALLOC(sizeof(*ia), M_IFADDR, M_WAITOK);
                        if (ia == NULL)
                                return (ENOBUFS);
                        bzero((caddr_t)ia, sizeof(*ia));
                        /* Initialize the address and masks */
                        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);
                        if (ifp->if_flags & IFF_POINTOPOINT) {
                                ia->ia_ifa.ifa_dstaddr
                                        = (struct sockaddr *)&ia->ia_dstaddr;
                                ia->ia_dstaddr.sin6_family = AF_INET6;
                                ia->ia_dstaddr.sin6_len = sizeof(ia->ia_dstaddr);
                        } else {
                                ia->ia_ifa.ifa_dstaddr = NULL;
                                bzero(&ia->ia_dstaddr, sizeof(ia->ia_dstaddr));
                        }
                        ia->ia_ifa.ifa_netmask
                                = (struct sockaddr *)&ia->ia_prefixmask;

                        ia->ia_ifp = ifp;

                        printf("in6_control: Attach dl_tag for if=%s%n\n", ifp->if_name, ifp->if_unit);
        
                        if (strcmp(ifp->if_name, "en") == 0)
                                dl_tag = ether_attach_inet6(ifp);

                        if (strcmp(ifp->if_name, "lo") == 0)
                                dl_tag = lo_attach_inet(ifp);
#if NGIF > 0
                        if (strcmp(ifp->if_name, "gif") == 0)
                                dl_tag = gif_attach_inet(ifp);
#endif
/* End of temp code */
                        ia->ia_ifa.ifa_dlt = dl_tag;


                        if ((oia = in6_ifaddr) != NULL) {
                                for ( ; oia->ia_next; oia = oia->ia_next)
                                        continue;
                                oia->ia_next = ia;
                        } else
                                in6_ifaddr = ia;
                        ia->ia_ifa.ifa_refcnt++;

#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);
#endif
                        ia->ia_ifa.ifa_refcnt++;

                        newifaddr = 1;
                } else
                        newifaddr = 0;

                if (cmd == SIOCAIFADDR_IN6) {
                        /* sanity for overflow - beware unsigned */
                        struct in6_addrlifetime *lt;
                        lt = &ifra->ifra_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;

        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 (!privileged)
                        return(EPERM);
                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);
                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;
#if COMPAT_IN6IFIOCTL           /* should be unused */
        case SIOCSIFDSTADDR_IN6:
                if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
                        return(EINVAL);
                oldaddr = ia->ia_dstaddr;
                ia->ia_dstaddr = ifr->ifr_dstaddr;

                /* link-local index check */
                if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_dstaddr.sin6_addr)) {
                        if (ia->ia_dstaddr.sin6_addr.s6_addr16[1] == 0) {
                                /* interface ID is not embedded by the user */
                                ia->ia_dstaddr.sin6_addr.s6_addr16[1]
                                        = htons(ifp->if_index);
                        } else if (ia->ia_dstaddr.sin6_addr.s6_addr16[1] !=
                                    htons(ifp->if_index)) {
                                ia->ia_dstaddr = oldaddr;
                                return(EINVAL); /* ifid is contradict */
                        }
                }
#ifdef __APPLE__
                error = dlil_ioctl(0, ifp, SIOCSIFDSTADDR, (caddr_t)ia);
                if (error == EOPNOTSUPP)
                        error = 0;
                if (error) { 
                        ia->ia_dstaddr = oldaddr;
                        return(error);
                }
#else
                if (ifp->if_ioctl && (error = (ifp->if_ioctl)
                                      (ifp, SIOCSIFDSTADDR, (caddr_t)ia))) {
#endif
                if (ia->ia_flags & IFA_ROUTE) {
                        ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
                        rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
                        ia->ia_ifa.ifa_dstaddr =
                                (struct sockaddr *)&ia->ia_dstaddr;
                        rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
                }
                break;

#endif
        case SIOCGIFALIFETIME_IN6:
                ifr->ifr_ifru.ifru_lifetime = ia->ia6_lifetime;
                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 SIOCSIFADDR_IN6:
                error = in6_ifinit(ifp, ia, &ifr->ifr_addr, 1);
#if 0
                /*
                 * the code chokes if we are to assign multiple addresses with
                 * the same address prefix (rtinit() will return EEXIST, which
                 * is not fatal actually).  we will get memory leak if we
                 * don't do it.
                 * -> we may want to hide EEXIST from rtinit().
                 */
  undo:
                if (error && newifaddr) {
#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 {
                                        printf("Couldn't unlink in6_ifaddr "
                                            "from ifp\n");
                                }
                        }
#else
                        TAILQ_REMOVE(&ifp->if_addrlist, &ia->ia_ifa, ifa_list);
#endif
                        IFAFREE(&ia->ia_ifa);

                        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 {
                                        printf("Didn't unlink in6_ifaddr "
                                            "from list\n");
                                }
                        }
                        IFAFREE(&ia->ia_ifa);
                }
#endif
                return error;

#if COMPAT_IN6IFIOCTL           /* XXX should be unused */
        case SIOCSIFNETMASK_IN6:
                ia->ia_prefixmask = ifr->ifr_addr;
                bzero(&net, sizeof(net));
                net.sin6_len = sizeof(struct sockaddr_in6);
                net.sin6_family = AF_INET6;
                net.sin6_port = htons(0);
                net.sin6_flowinfo = htonl(0);
                net.sin6_addr.s6_addr32[0]
                        = ia->ia_addr.sin6_addr.s6_addr32[0] &
                                ia->ia_prefixmask.sin6_addr.s6_addr32[0];
                net.sin6_addr.s6_addr32[1]
                        = ia->ia_addr.sin6_addr.s6_addr32[1] &
                                ia->ia_prefixmask.sin6_addr.s6_addr32[1];
                net.sin6_addr.s6_addr32[2]
                        = ia->ia_addr.sin6_addr.s6_addr32[2] &
                                ia->ia_prefixmask.sin6_addr.s6_addr32[2];
                net.sin6_addr.s6_addr32[3]
                        = ia->ia_addr.sin6_addr.s6_addr32[3] &
                                ia->ia_prefixmask.sin6_addr.s6_addr32[3];
                ia->ia_net = net;
                break;
#endif

        case SIOCAIFADDR_IN6:
                prefixIsNew = 0;
                hostIsNew = 1;

                if (ifra->ifra_addr.sin6_len == 0) {
                        ifra->ifra_addr = ia->ia_addr;
                        hostIsNew = 0;
                } else if (IN6_ARE_ADDR_EQUAL(&ifra->ifra_addr.sin6_addr,
                                              &ia->ia_addr.sin6_addr))
                        hostIsNew = 0;

                /* Validate address families: */
                /*
                 * 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);
                /*
                 * The prefixmask must have a family of AF_UNSPEC or AF_INET6.
                 */
                if (ifra->ifra_prefixmask.sin6_family != AF_INET6 &&
                    ifra->ifra_prefixmask.sin6_family != AF_UNSPEC)
                        return(EAFNOSUPPORT);

                if (ifra->ifra_prefixmask.sin6_len) {
                        in6_ifscrub(ifp, ia);
                        ia->ia_prefixmask = ifra->ifra_prefixmask;
                        prefixIsNew = 1;
                }
                if ((ifp->if_flags & IFF_POINTOPOINT) &&
                    (ifra->ifra_dstaddr.sin6_family == AF_INET6)) {
                        in6_ifscrub(ifp, ia);
                        oldaddr = ia->ia_dstaddr;
                        ia->ia_dstaddr = ifra->ifra_dstaddr;
                        /* link-local index check: should be a separate function? */
                        if (IN6_IS_ADDR_LINKLOCAL(&ia->ia_dstaddr.sin6_addr)) {
                                if (ia->ia_dstaddr.sin6_addr.s6_addr16[1] == 0) {
                                        /*
                                         * interface ID is not embedded by
                                         * the user
                                         */
                                        ia->ia_dstaddr.sin6_addr.s6_addr16[1]
                                                = htons(ifp->if_index);
                                } else if (ia->ia_dstaddr.sin6_addr.s6_addr16[1] !=
                                            htons(ifp->if_index)) {
                                        ia->ia_dstaddr = oldaddr;
                                        return(EINVAL); /* ifid is contradict */
                                }
                        }
                        prefixIsNew = 1; /* We lie; but effect's the same */
                }
                if (hostIsNew || prefixIsNew) {
                        error = in6_ifinit(ifp, ia, &ifra->ifra_addr, 0);
#if 0
                        if (error)
                                goto undo;
#endif
                }
                if (hostIsNew && (ifp->if_flags & IFF_MULTICAST)) {
                        int error_local = 0;

                        /*
                         * 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;
                        (void)in6_addmulti(&llsol, ifp, &error_local);
                        if (error == 0)
                                error = error_local;
                }

                ia->ia6_flags = ifra->ifra_flags;
                ia->ia6_flags &= ~IN6_IFF_DUPLICATED;   /*safety*/
                ia->ia6_flags &= ~IN6_IFF_NODAD;        /* Mobile IPv6 */

                ia->ia6_lifetime = ifra->ifra_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;

                /*
                 * Perform DAD, if needed.
                 * XXX It may be of use, if we can administratively
                 * disable DAD.
                 */
                switch (ifp->if_type) {
                case IFT_ARCNET:
                case IFT_ETHER:
                case IFT_FDDI:
#if 0
                case IFT_ATM:
                case IFT_SLIP:
                case IFT_PPP:
#endif
                        /* Mobile IPv6 modification */
                        if ((ifra->ifra_flags & IN6_IFF_NODAD) == 0) {
                                ia->ia6_flags |= IN6_IFF_TENTATIVE;
                                nd6_dad_start((struct ifaddr *)ia, NULL);
                        }
                        break;
                case IFT_DUMMY:
                case IFT_FAITH:
                case IFT_GIF:
                case IFT_LOOP:
                default:
                        break;
                }

                if (hostIsNew) {
                        int iilen;
                        int error_local = 0;

                        iilen = (sizeof(ia->ia_prefixmask.sin6_addr) << 3) -
                                in6_mask2len(&ia->ia_prefixmask.sin6_addr);
                        error_local = in6_prefix_add_ifid(iilen, ia);
                        if (error == 0)
                                error = error_local;
                }

                return(error);

        case SIOCDIFADDR_IN6:
                in6_purgeaddr(&ia->ia_ifa, ifp);
                break;

        default:
#ifdef __APPLE__
                error = dlil_ioctl(0, ifp, cmd, (caddr_t)data);
                if (error == EOPNOTSUPP)
                        error = 0;
                return error;

#else
                if (ifp == NULL || ifp->if_ioctl == 0)
                        return(EOPNOTSUPP);
                return((*ifp->if_ioctl)(ifp, cmd, data));
#endif
        }
        return(0);
}

void
in6_purgeaddr(ifa, ifp)
        struct ifaddr *ifa;
        struct ifnet *ifp;
{
        struct in6_ifaddr *oia, *ia = (void *) ifa;

        in6_ifscrub(ifp, ia);

        if (ifp->if_flags & IFF_MULTICAST) {
                /*
                 * delete solicited multicast addr for deleting host id
                 */
                struct in6_multi *in6m;
                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] =
                        ia->ia_addr.sin6_addr.s6_addr32[3];
                llsol.s6_addr8[12] = 0xff;

                IN6_LOOKUP_MULTI(llsol, ifp, in6m);
                if (in6m)
                        in6_delmulti(in6m);
        }

#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
                        printf("Couldn't unlink in6_ifaddr from ifp\n");
        }
#else
        TAILQ_REMOVE(&ifp->if_addrlist, &ia->ia_ifa, ifa_list);
#endif
        IFAFREE(&ia->ia_ifa);

        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
                        printf("Didn't unlink in6_ifaddr from list\n");
        }
        {
                int iilen;

                iilen = (sizeof(oia->ia_prefixmask.sin6_addr) << 3) -
                        in6_mask2len(&oia->ia_prefixmask.sin6_addr);
                in6_prefix_remove_ifid(iilen, oia);
        }
#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3) && !defined (__APPLE__)
        if (oia->ia6_multiaddrs.lh_first != NULL)
                in6_savemkludge(oia);
#endif

        IFAFREE(&oia->ia_ifa);
}

/*
 * 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) && !defined (__APPLE__)
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;

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

        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_family = AF_INET6;
                ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
                in6_len2mask(&ifra.ifra_prefixmask.sin6_addr, prefixlen);

                ifra.ifra_flags = iflr->flags & ~IFLR_PREFIX;
#if !defined(__bsdi__) && !(defined(__FreeBSD__) && __FreeBSD__ < 3) && !defined (__APPLE__)
                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_len2mask(&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_len2mask(&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)
#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));
                        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) {
                        /* fill in the if_laddrreq structure */
                        bcopy(&ia->ia_addr, &iflr->addr, ia->ia_addr.sin6_len);

                        if ((ifp->if_flags & IFF_POINTOPOINT) != 0) {
                                bcopy(&ia->ia_dstaddr, &iflr->dstaddr,
                                        ia->ia_dstaddr.sin6_len);
                        } else
                                bzero(&iflr->dstaddr, sizeof(iflr->dstaddr));

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

                        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) && !defined (__APPLE__)
                        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*/
}

/*
 * Delete any existing route for an interface.
 */
void
in6_ifscrub(ifp, ia)
        register struct ifnet *ifp;
        register struct in6_ifaddr *ia;
{
        if ((ia->ia_flags & IFA_ROUTE) == 0)
                return;
        if (ifp->if_flags & (IFF_LOOPBACK | IFF_POINTOPOINT))
                rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
        else
                rtinit(&(ia->ia_ifa), (int)RTM_DELETE, 0);
        ia->ia_flags &= ~IFA_ROUTE;

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

/*
 * Initialize an interface's intetnet6 address
 * and routing table entry.
 */
int
in6_ifinit(ifp, ia, sin6, scrub)
        struct ifnet *ifp;
        struct in6_ifaddr *ia;
        struct sockaddr_in6 *sin6;
        int scrub;
{
        struct  sockaddr_in6 oldaddr;
        int     error, flags = RTF_UP;
        u_long dl_tag;
        int     s = splimp();

        oldaddr = ia->ia_addr;
        ia->ia_addr = *sin6;
        /*
         * Give the interface a chance to initialize
         * if this is its first address,
         * and to validate the address if necessary.
         */
#ifdef __APPLE__
        error = dlil_ioctl(0, ifp, SIOCSIFADDR, (caddr_t)ia) ; 
        if (error == EOPNOTSUPP)
                error = 0;
        if (error) {

#else
        if (ifp->if_ioctl &&
           (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia))) {
#endif
                printf("in6_ifinit SIOCSIFADDR for if=%s returns error=%x\n", if_name(ifp), error);
                splx(s);
                ia->ia_addr = oldaddr;
                return(error);
        }

        switch (ifp->if_type) {
        case IFT_ARCNET:
        case IFT_ETHER:
        case IFT_FDDI:
                ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
                ia->ia_ifa.ifa_flags |= RTF_CLONING;
                break;
        case IFT_PPP:
                ia->ia_ifa.ifa_rtrequest = nd6_p2p_rtrequest;
                ia->ia_ifa.ifa_flags |= RTF_CLONING;
                break;
        }

        splx(s);
        if (scrub) {
                ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
                in6_ifscrub(ifp, ia);
                ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
        }
        /* xxx
         * in_socktrim
         */
        /*
         * Add route for the network.
         */
        ia->ia_ifa.ifa_metric = ifp->if_metric;
        if (ifp->if_flags & IFF_LOOPBACK) {
                ia->ia_ifa.ifa_dstaddr = ia->ia_ifa.ifa_addr;
                flags |= RTF_HOST;
        } else if (ifp->if_flags & IFF_POINTOPOINT) {
                if (ia->ia_dstaddr.sin6_family != AF_INET6)
                        return(0);
                flags |= RTF_HOST;
        }
        if ((error = rtinit(&(ia->ia_ifa), (int)RTM_ADD, flags)) == 0)
                ia->ia_flags |= IFA_ROUTE;

        /* Add ownaddr as loopback rtentry, if necessary(ex. on p2p link). */
        in6_ifaddloop(&(ia->ia_ifa));

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

#ifdef __APPLE__
         printf("in6_ifinit: Attach dl_tag for if=%s%n\n", ifp->if_name, ifp->if_unit);

         if (strcmp(ifp->if_name, "en") == 0)
                dl_tag = ether_attach_inet6(ifp);
 
         if (strcmp(ifp->if_name, "lo") == 0)
                dl_tag = lo_attach_inet(ifp);
#if NGIF > 0
         if (strcmp(ifp->if_name, "gif") == 0)
                dl_tag = gif_attach_inet(ifp);
#endif
/* End of temp code */
         ia->ia_ifa.ifa_dlt = dl_tag; 
#endif

        return(error);
}

#if !(defined(__FreeBSD__) && __FreeBSD__ >= 3)  && !defined (__APPLE__)
/*
 * 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);
                        ia->ia_ifa.ifa_refcnt++;
                        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;

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

                LIST_INIT(&mk->mk_head);
                mk->mk_ifp = oia->ia_ifp;

                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);
                }

                if (mk->mk_head.lh_first != NULL) {
                        LIST_INSERT_HEAD(&in6_mk, mk, mk_entry);
                } else {
                        FREE(mk, M_IPMADDR);
                }
        }
}

/*
 * 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;
                                ia->ia_ifa.ifa_refcnt++;
                                LIST_INSERT_HEAD(&ia->ia6_multiaddrs,
                                                 in6m, in6m_entry);
                        }
                        LIST_REMOVE(mk, mk_entry);
                        _FREE(mk, M_IPMADDR);
                        break;
                }
        }
}

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)
        register struct in6_addr *maddr6;
        register struct ifnet *ifp;
        int *errorp;
{
        struct  in6_ifaddr *ia;
        struct  in6_ifreq ifr;
        struct  in6_multi *in6m;
#if __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_NOTWAIT);
                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;
                ia->ia_ifa.ifa_refcnt++; /* 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;
#ifdef __APPLE__
                 *errorp = dlil_ioctl(0, ifp, SIOCADDMULTI, (caddr_t)&ifr);
                 printf("in6_addmulti: if=%s%n dlil_ioctl returns=%d\n", ifp->if_name, ifp->if_unit, *errorp);
                 if (*errorp == EOPNOTSUPP)
                                *errorp = 0;

#else
                if (ifp->if_ioctl == NULL)
                        *errorp = ENXIO; /* XXX: appropriate? */
                else
                        *errorp = (*ifp->if_ioctl)(ifp, SIOCADDMULTI,
                                                    (caddr_t)&ifr);
#endif
                if (*errorp) {
                        LIST_REMOVE(in6m, in6m_entry);
                        _FREE(in6m, M_IPMADDR);
                        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;
#if __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;
#ifdef __APPLE__
                dlil_ioctl(0, in6m->in6m_ifp, SIOCDELMULTI, (caddr_t)&ifr);
#else
                (*in6m->in6m_ifp->if_ioctl)(in6m->in6m_ifp,
                                            SIOCDELMULTI, (caddr_t)&ifr);
#endif
                _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)
        register struct in6_addr *maddr6;
        register 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 */

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

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
        for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#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.
 */
struct in6_ifaddr *
in6ifa_ifpwithaddr(ifp, addr)
        struct ifnet *ifp;
        struct in6_addr *addr;
{
        register struct ifaddr *ifa;

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
        for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#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);
}

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

/*
 * Get a scope of the address. Node-local, link-local, site-local or global.
 */
int
in6_addrscope (addr)
struct in6_addr *addr;
{
        int scope;

        if (addr->s6_addr8[0] == 0xfe) {
                scope = addr->s6_addr8[1] & 0xc0;

                switch (scope) {
                case 0x80:
                        return IPV6_ADDR_SCOPE_LINKLOCAL;
                        break;
                case 0xc0:
                        return IPV6_ADDR_SCOPE_SITELOCAL;
                        break;
                default:
                        return IPV6_ADDR_SCOPE_GLOBAL; /* just in case */
                        break;
                }
        }


        if (addr->s6_addr8[0] == 0xff) {
                scope = addr->s6_addr8[1] & 0x0f;

                /*
                 * due to other scope such as reserved,
                 * return scope doesn't work.
                 */
                switch (scope) {
                case IPV6_ADDR_SCOPE_NODELOCAL:
                        return IPV6_ADDR_SCOPE_NODELOCAL;
                        break;
                case IPV6_ADDR_SCOPE_LINKLOCAL:
                        return IPV6_ADDR_SCOPE_LINKLOCAL;
                        break;
                case IPV6_ADDR_SCOPE_SITELOCAL:
                        return IPV6_ADDR_SCOPE_SITELOCAL;
                        break;
                default:
                        return IPV6_ADDR_SCOPE_GLOBAL;
                        break;
                }
        }

        if (bcmp(&in6addr_loopback, addr, sizeof(addr) - 1) == 0) {
                if (addr->s6_addr8[15] == 1) /* loopback */
                        return IPV6_ADDR_SCOPE_NODELOCAL;
                if (addr->s6_addr8[15] == 0) /* unspecified */
                        return IPV6_ADDR_SCOPE_LINKLOCAL;
        }

        return IPV6_ADDR_SCOPE_GLOBAL;
}

int
in6_addr2scopeid(ifp, addr)
        struct ifnet *ifp;      /* must not be NULL */
        struct in6_addr *addr;  /* must not be NULL */
{
        int scope = in6_addrscope(addr);
                
        switch(scope) {
        case IPV6_ADDR_SCOPE_NODELOCAL:
                return(-1);     /* XXX: is this an appropriate value? */

        case IPV6_ADDR_SCOPE_LINKLOCAL:
                /* XXX: we do not distinguish between a link and an I/F. */
                return(ifp->if_index);

        case IPV6_ADDR_SCOPE_SITELOCAL:
                return(0);      /* XXX: invalid. */

        default:
                return(0);      /* XXX: treat as global. */
        }
}

/*
 * 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;
}

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
 */
struct in6_ifaddr *
in6_ifawithscope(oifp, dst)
        register struct ifnet *oifp;
        register struct in6_addr *dst;
{
        int dst_scope = in6_addrscope(dst), src_scope, best_scope = 0;
        int blen = -1;
        struct ifaddr *ifa;
        struct ifnet *ifp;
        struct in6_ifaddr *ifa_best = NULL;
        
        if (oifp == NULL) {
                printf("in6_ifawithscope: output interface is not specified\n");
                return(NULL);
        }

        /*
         * We search for all addresses on all interfaces from the beginning.
         * Comparing an interface with the outgoing interface will be done
         * only at the final stage of tiebreaking.
         */
#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
        {
                /*
                 * We can never take an address that breaks the scope zone
                 * of the destination.
                 */
                if (in6_addr2scopeid(ifp, dst) != in6_addr2scopeid(oifp, dst))
                        continue;

#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
                {
                        int tlen = -1, dscopecmp, bscopecmp, matchcmp;

                        if (ifa->ifa_addr->sa_family != AF_INET6)
                                continue;

                        src_scope = in6_addrscope(IFA_IN6(ifa));

#if ADDRSELECT_DEBUG            /* should be removed after stabilization */
                        dscopecmp = IN6_ARE_SCOPE_CMP(src_scope, dst_scope);
                        printf("in6_ifawithscope: dst=%s bestaddr=%s, "
                               "newaddr=%s, scope=%x, dcmp=%d, bcmp=%d, "
                               "matchlen=%d, flgs=%x\n",
                               ip6_sprintf(dst),
                               ifa_best ? ip6_sprintf(&ifa_best->ia_addr.sin6_addr) : "none",
                               ip6_sprintf(IFA_IN6(ifa)), src_scope,
                               dscopecmp,
                               ifa_best ? IN6_ARE_SCOPE_CMP(src_scope, best_scope) : -1,
                               in6_matchlen(IFA_IN6(ifa), dst),
                               ((struct in6_ifaddr *)ifa)->ia6_flags);
#endif

                        /*
                         * Don't use an address before completing DAD
                         * nor a duplicated address.
                         */
                        if (((struct in6_ifaddr *)ifa)->ia6_flags &
                            IN6_IFF_NOTREADY)
                                continue;

                        /* XXX: is there any case to allow anycasts? */
                        if (((struct in6_ifaddr *)ifa)->ia6_flags &
                            IN6_IFF_ANYCAST)
                                continue;

                        if (((struct in6_ifaddr *)ifa)->ia6_flags &
                            IN6_IFF_DETACHED)
                                continue;

                        /*
                         * If this is the first address we find,
                         * keep it anyway.
                         */
                        if (ifa_best == NULL)
                                goto replace;

                        /*
                         * ifa_best is never NULL beyond this line except
                         * within the block labeled "replace".
                         */

                        /*
                         * If ifa_best has a smaller scope than dst and
                         * the current address has a larger one than
                         * (or equal to) dst, always replace ifa_best.
                         * Also, if the current address has a smaller scope
                         * than dst, ignore it unless ifa_best also has a
                         * smaller scope.
                         */
                        if (IN6_ARE_SCOPE_CMP(best_scope, dst_scope) < 0 &&
                            IN6_ARE_SCOPE_CMP(src_scope, dst_scope) >= 0)
                                goto replace;
                        if (IN6_ARE_SCOPE_CMP(src_scope, dst_scope) < 0 &&
                            IN6_ARE_SCOPE_CMP(best_scope, dst_scope) >= 0)
                                continue;

                        /*
                         * A deprecated address SHOULD NOT be used in new
                         * communications if an alternate (non-deprecated)
                         * address is available and has sufficient scope.
                         * RFC 2462, Section 5.5.4.
                         */
                        if (((struct in6_ifaddr *)ifa)->ia6_flags &
                            IN6_IFF_DEPRECATED) {
                                /*
                                 * Ignore any deprecated addresses if
                                 * specified by configuration.
                                 */
                                if (!ip6_use_deprecated)
                                        continue;

                                /*
                                 * If we have already found a non-deprecated
                                 * candidate, just ignore deprecated addresses.
                                 */
                                if ((ifa_best->ia6_flags & IN6_IFF_DEPRECATED)
                                    == 0)
                                        continue;
                        }

                        /*
                         * A non-deprecated address is always preferred
                         * to a deprecated one regardless of scopes and
                         * address matching.
                         */
                        if ((ifa_best->ia6_flags & IN6_IFF_DEPRECATED) &&
                            (((struct in6_ifaddr *)ifa)->ia6_flags &
                             IN6_IFF_DEPRECATED) == 0)
                                goto replace;

                        /*
                         * At this point, we have two cases:
                         * 1. we are looking at a non-deprecated address,
                         *    and ifa_best is also non-deprecated.
                         * 2. we are looking at a deprecated address,
                         *    and ifa_best is also deprecated.
                         * Also, we do not have to consider a case where
                         * the scope of if_best is larger(smaller) than dst and
                         * the scope of the current address is smaller(larger)
                         * than dst. Such a case has already been covered.
                         * Tiebreaking is done according to the following
                         * items:
                         * - the scope comparison between the address and
                         *   dst (dscopecmp)
                         * - the scope comparison between the address and
                         *   ifa_best (bscopecmp)
                         * - if the address match dst longer than ifa_best
                         *   (matchcmp)
                         * - if the address is on the outgoing I/F (outI/F)
                         *
                         * Roughly speaking, the selection policy is
                         * - the most important item is scope. The same scope
                         *   is best. Then search for a larger scope.
                         *   Smaller scopes are the last resort.
                         * - A deprecated address is chosen only when we have
                         *   no address that has an enough scope, but is
                         *   prefered to any addresses of smaller scopes.
                         * - Longest address match against dst is considered
                         *   only for addresses that has the same scope of dst.
                         * - If there is no other reasons to choose one,
                         *   addresses on the outgoing I/F are preferred.
                         *
                         * The precise decision table is as follows:
                         * dscopecmp bscopecmp matchcmp outI/F | replace?
                         *    !equal     equal      N/A    Yes |      Yes (1)
                         *    !equal     equal      N/A     No |       No (2)
                         *    larger    larger      N/A    N/A |       No (3)
                         *    larger   smaller      N/A    N/A |      Yes (4)
                         *   smaller    larger      N/A    N/A |      Yes (5)
                         *   smaller   smaller      N/A    N/A |       No (6)
                         *     equal   smaller      N/A    N/A |      Yes (7)
                         *     equal    larger       (already done)
                         *     equal     equal   larger    N/A |      Yes (8)
                         *     equal     equal  smaller    N/A |       No (9)
                         *     equal     equal    equal    Yes |      Yes (a)
                         *     eaual     eqaul    equal     No |       No (b)
                         */
                        dscopecmp = IN6_ARE_SCOPE_CMP(src_scope, dst_scope);
                        bscopecmp = IN6_ARE_SCOPE_CMP(src_scope, best_scope);

                        if (dscopecmp && bscopecmp == 0) {
                                if (oifp == ifp) /* (1) */
                                        goto replace;
                                continue; /* (2) */
                        }
                        if (dscopecmp > 0) {
                                if (bscopecmp > 0) /* (3) */
                                        continue;
                                goto replace; /* (4) */
                        }
                        if (dscopecmp < 0) {
                                if (bscopecmp > 0) /* (5) */
                                        goto replace;
                                continue; /* (6) */
                        }

                        /* now dscopecmp must be 0 */
                        if (bscopecmp < 0)
                                goto replace; /* (7) */

                        /*
                         * At last both dscopecmp and bscopecmp must be 0.
                         * We need address matching against dst for
                         * tiebreaking.
                         */
                        tlen = in6_matchlen(IFA_IN6(ifa), dst);
                        matchcmp = tlen - blen;
                        if (matchcmp > 0) /* (8) */
                                goto replace;
                        if (matchcmp < 0) /* (9) */
                                continue;
                        if (oifp == ifp) /* (a) */
                                goto replace;
                        continue; /* (b) */

                  replace:
                        ifa_best = (struct in6_ifaddr *)ifa;
                        blen = tlen >= 0 ? tlen :
                                in6_matchlen(IFA_IN6(ifa), dst);
                        best_scope = in6_addrscope(&ifa_best->ia_addr.sin6_addr);
                }
        }

        /* count statistics for future improvements */
        if (ifa_best == NULL)
                ip6stat.ip6s_sources_none++;
        else {
                if (oifp == ifa_best->ia_ifp)
                        ip6stat.ip6s_sources_sameif[best_scope]++;
                else
                        ip6stat.ip6s_sources_otherif[best_scope]++;

                if (best_scope == dst_scope)
                        ip6stat.ip6s_sources_samescope[best_scope]++;
                else
                        ip6stat.ip6s_sources_otherscope[best_scope]++;

                if ((ifa_best->ia6_flags & IN6_IFF_DEPRECATED) != 0)
                        ip6stat.ip6s_sources_deprecated[best_scope]++;
        }

        return(ifa_best);
}

/*
 * 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)
        register struct ifnet *ifp;
        register 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;

#if 0
#if MIP6
        /*
         * This is needed to assure that the Home Address is used for
         * outgoing packets when not at home. We can't choose any other
         * address if we want to keep connections up during movement.
         */
        if (mip6_get_home_prefix_hook) {        /* Only Mobile Node */
                struct nd_prefix *pr;
                if ((pr = (*mip6_get_home_prefix_hook)()) &&
                    !IN6_IS_ADDR_UNSPECIFIED(&pr->ndpr_addr))
                {
                        if (dst_scope == in6_addrscope(&pr->ndpr_addr)) {
#if MIP6_DEBUG
                                /* Noisy but useful */
                                mip6_debug("%s: Local address %s is chosen "
                                           "for pcb to dest %s.\n",
                                           __FUNCTION__,
                                           ip6_sprintf(&pr->ndpr_addr),
                                           ip6_sprintf(dst));
#endif
                                return(in6ifa_ifpwithaddr(ifp, &pr->ndpr_addr));
                        }
                }
        }
#endif /* MIP6 */
#endif /* 0 */

        /*
         * 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)
#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)
#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;
        struct sockaddr_dl *sdl;
        int type;
#if __bsdi__
        u_char ea[ETHER_ADDR_LEN];
#else
        struct ether_addr ea;
#endif
        int off;
        int dad_delay;          /* delay ticks before DAD output */

        bzero(&ea, sizeof(ea));
        sdl = NULL;

#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
        for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#else
        for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next)
#endif
        {
                if (ifa->ifa_addr->sa_family == AF_INET6
                 && IN6_IS_ADDR_LINKLOCAL(&((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr)) {
                        goto dad;
                }
                if (ifa->ifa_addr->sa_family != AF_LINK)
                        continue;
                sdl = (struct sockaddr_dl *)ifa->ifa_addr;
                break;
        }

        switch (ifp->if_type) {
        case IFT_LOOP:
                in6_ifattach(ifp, IN6_IFT_LOOP, NULL, 1);
                break;
        case IFT_SLIP:
        case IFT_PPP:
        case IFT_DUMMY:
        case IFT_GIF:
        case IFT_FAITH:
                type = IN6_IFT_P2P;
                in6_ifattach(ifp, type, 0, 1);
                break;
#if IFT_STF
        case IFT_STF:
                /*
                 * This is VERY awkward to call nd6_ifattach while we will
                 * not do ND at all on the interface.  It is necessary for
                 * initializing default hoplimit, and ND mtu.
                 */
                nd6_ifattach(ifp);
                break;
#endif
        case IFT_ETHER:
        case IFT_FDDI:
        case IFT_ATM:
                type = IN6_IFT_802;
                if (sdl == NULL)
                        break;
                off = sdl->sdl_nlen;
                if (bcmp(&sdl->sdl_data[off], &ea, sizeof(ea)) != 0)
                        in6_ifattach(ifp, type, LLADDR(sdl), 0);
                break;
        case IFT_ARCNET:
                type = IN6_IFT_ARCNET;
                if (sdl == NULL)
                        break;
                off = sdl->sdl_nlen;
                if (sdl->sdl_data[off] != 0)    /* XXX ?: */
                        in6_ifattach(ifp, type, LLADDR(sdl), 0);
                break;
        default:
                break;
        }

dad:
        dad_delay = 0;
#if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3)
        for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
#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);
        }
}

/*
 * 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 MAPPED_ADDR_ENABLED
/* 
 * 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 /* MAPPED_ADDR_ENABLED */